Search
Search Results
-
1231. [Article] Nearshore distribution of barnacle and mussel larvae and oceanographic mechanisms of onshore transport and delivery
Recruitment of larvae from the plankton is an important determinant of community structure in marine systems. In populations of many marine species, recruitment determines the basic demographic parameters ...Citation Citation
- Title:
- Nearshore distribution of barnacle and mussel larvae and oceanographic mechanisms of onshore transport and delivery
- Author:
- Tyburczy, Joe
Recruitment of larvae from the plankton is an important determinant of community structure in marine systems. In populations of many marine species, recruitment determines the basic demographic parameters of immigration, emigration, and reproduction. Moreover, the effect of recruitment as an "ecological subsidy" can determine the strength of interactions among species and whether populations are limited by recruitment itself, or by competition or predation. For this reason, understanding the transport of larvae is essential for management and conservation. In Chapter 2, my coauthors and I investigated the vertical and cross-shelf distribution of barnacle and bivalve larvae with a series of paired day/night sampling cruises off the coast of central Chile. Barnacle larvae were generally found close to shore (within 1.5 km), and the cross-shelf distribution of all taxa varied little despite contrasting upwelling conditions. Since current velocities decrease quickly with proximity to shore, larvae distributed in the nearshore are less likely to be dispersed long distances. Further, the consistent cross-shelf distribution of larvae suggests that they are not necessarily swept on- or offshore by upwelling or relaxation. Depth distributions consistent with classical diel vertical migration (DVM; swimming deeper during the day, shallower at night) were found in barnacle nauplii, but not barnacle cyprids or in bivalve larvae. One potential advantage of DVM is that it may limit offshore transport and thereby increase the odds that larvae will reach suitable habitat when they are competent to settle. Another possible benefit of DVM is that it may increase feeding opportunity in shallow water at night when visual predation risk is low, while providing refuge at depth during the day when visual predation in the upper water column is greater. In Chapter 3, my coauthors and I undertook a large-scale study in northern Monterey Bay, CA that integrated high-frequency physical and biological sampling to allow resolution of multiple different potential mechanisms of onshore larval transport and settlement. Depending on location within Monterey Bay, three processes were found to be associated with onshore barnacle settlement: regional upwelling, local diurnal upwelling driven by afternoon sea breezes, and the passage of an upwelling shadow front. Based on these findings we propose a novel conceptual model that encompasses oceanographic processes at multiple scales and reconciles apparent inconsistencies between empirical results and existing theories. In Chaper 4, my coauthors and I developed a simple larval transport model using data on currents, offshore flux of barnacle larvae, and onshore settlement of barnacles from the empirical study in Chapter 3. A parameter set was found that produced model settlement correlated with observed settlement. The fit of modeled and observed settlement was sensitive to model parameters. However, for all parameter sets examined, onshore transport of particles was much greater at depth. This result from the larval transport model is consistent with the conceptual model proposed in Chapter 3. Further, during intervals when onshore transport was observed, model particle trajectories clearly show onshore transport only at depth via two of the mechanisms identified in Chapter 3 (local diurnal upwelling and passage of the upwelling shadow front).
-
1232. [Article] The 1951 Alsea River silver salmon tagging program
During a tagging operation conducted in 1951 on the Alsea River, 1,142 adult silver salmon were tagged with plastic Petersen-type tags and stainless steel jaw tags. An attempt was made to determine whether ...Citation Citation
- Title:
- The 1951 Alsea River silver salmon tagging program
- Author:
- Oregon. Fish Commission, Cleaver, Fred C. (Frederick Charles), 1916-, Morgan, Alfred R.
During a tagging operation conducted in 1951 on the Alsea River, 1,142 adult silver salmon were tagged with plastic Petersen-type tags and stainless steel jaw tags. An attempt was made to determine whether tagged fish released in different apparent conditions suffered differential mortalities. Under the hypothesis that the recovery of the fish in the commercial fishery was independent of the apparent condition of the fish when it was released, a significant value of chi-square was obtained. However, it was concluded that this significance was a result of sampling differences and not actually due to differences in mortality. The number of fish taken in the commercial catch each week was calculated by dividing the number of pounds in the weekly catch by the average weight of the fish in the samples for that week. It was calculated that the commercial fishery took approximately 14,000 fish during the season, which was only about 15 per cent of the run available to the fishery. This is an extremely low fishing mortality and is considerably lower than had been expected. The number of tags taken each week by the commercial fishery was calculated by dividing the number of fish in the catch each week by the number of fish per tag in the samples for the week. It was calculated that 67 tags were taken during the season by the commercial fishery. This number of recoveries was 15.5 per cent of the 438 tags available to the fishery. With the cooperation of a number of boat moorages on the Alsea River, an estimate of the sport catch of silver salmon was made. It was calculated that the lower river sport fishery took approximately 3,000 adult silvers with an additional 500 fish being taken by the bank fishery. The weight of the total catch of 3,500 fish was calculated to be about 33,000 pounds. This weight formed 20.2 percent of the combined commercial and sport catches. It was calculated that 18 tagged fish were taken in the sport catch. A total of 44 numbered Petersen and jaw tags were recovered from both dead and live fish which had reached spawning areas. This number includes three tags recovered from the spawning grounds of adjacent streams. When the tagged fish were examined according to areas recovered, it was found that Drift Creek had a smaller number of fish per tag than any other area with one exception. Recoveries appeared to be distributed throughout the drainage from any particular time of tagging. Fish enter the lower river together, then separate to the various spawning areas in the system. Several fish moved from the tagging location in the Alsea River to adjacent streams. About 7 percent of the total recoveries in Table 12 were made from streams other than the Alsea River. The Petersen and jaw tag recoveries in the samples of the commercial catch were examined for selection of the Petersen tags by the nets. The percentage by size group in the catch of fish with each type of tag was about the same as the percentage by size group with each type of tag at the time of release. Large losses of tags in the fishery would have been reflected by a higher number of fish per tag on the spawning grounds. Since the gill-nets did not appear to be selective on either type of tag, the Petersen tags, jaw tags, and tag scars were combined in the calculations involving tag recoveries. After the fish moved beyond the fishing area, many still did not move rapidly to the spawning grounds. Several were taken in tidewater or in the vicinity of tidewater 48-58 days after they had been tagged. The average time between tagging and recovery on the spawning grounds was 63 days for live fish and 70 days for dead fish. Using the method proposed by Schaefer (1951a) for obtaining a population estimate from spawning ground recoveries, an estimate of the population available to the fishery was made from the number of tags recovered by sampling the commercial catch. It was calculated that approximately 90,000 fish were available to the fishery. About 89,000 fish were calculated to be available to the fishery when the equation N = nt/s was used, where N = the population, n = the sample size, t = the number of fish tagged, and s = the number of tag recoveries. The 95 percent limits of confidence for the population estimate derived from the equation N = nt/s were calculated using the method developed by Chapman (1948). The lower limit was found to be 63,736 fish, and the upper limit was 119,371 fish. Approximately 63,000 of the fish available to the commercial fishery continued the migration to the spawning grounds. Spawning ground tag recoveries provided an estimate of the population in the lower river which was in close agreement with the estimate of the population made from tag recoveries in the commercial fishery.
-
1233. [Article] A study of the accuracy in the methods of sampling, preserving, and testing milk for fat at Oregon milk plants
A study was undertaken to determine, by methods and equipment, the variations between of sampling, preserving, and testing milk for fat during the various seasons of the year, and to try and solve the ...Citation Citation
- Title:
- A study of the accuracy in the methods of sampling, preserving, and testing milk for fat at Oregon milk plants
- Author:
- Robichaux, Roy Paul, 1909-
A study was undertaken to determine, by methods and equipment, the variations between of sampling, preserving, and testing milk for fat during the various seasons of the year, and to try and solve the problem whereby the sampling, preserving, and testing of milk for fat at milk plants could be more uniformly accomplished by different operators. During the period from May 1939 to April 1940 a total of 2064 tests by the Babcock method and 1032 tests by the Mojonnier method were made according to a standardized procedure. A total of 900 daily samples of milk, 12 five day-, 60 seven day-, and 60 fifteen-day composite samples of milk were included in the tests that comprised 10 complete "Units" over the different seasons of the year. Small decreases occurred in the fat percentages of composite samples as compared to the average of daily tests on the same samples of milk. These decreases amounted to 0.016, 0.021, and 0.027 for the five-, seven-, and fifteen-day composites respectively by the Babcock method of testing and 0.023, 0.021, and 0.055 for the three storage periods by the Mojonnier method of testing. The above decreases wore not found to be significant when the data was subjected to a statistical analysis. The Babcock results averaged approximately 0.075 higher in the percentage than the Mojonnier results on the same fresh samples of milk and also on the 5, and 7 day composites. The Babcock results averaged 0.104- higher than the Mojonnier on the 15-day composites. The differences obtained by the Babcock and Mojonnier methods of testing on both daily and composite samples of milk were found to be very significant. Numerous variations from standardized procedure were conducted to determine the effect of such variations on the final fat test. This comparative study included more than 2000 individual tests by the Babcock method and 165 individual determinations by the Mojonnier analysis. Results of these tests showed that: Variations in handling 7, and 15 day composites, such as, storage temperatures of 70° F. or above, not mixing the daily portions properly, and using unsterilized bottles, caused decreases from the average daily tests which amounted to between 0.04 and 0.14. Formalin did not prove to be superior to mercuric chloride as a preservative of milk samples, Saponin did not prevent the decline in the test of composite milk samples. Glymol added to the fat column to remove the upper meniscus in the Babcock test lowered the test by 0.192. The following variations in the Babcock testing technique were found to have a significant effect on the final results obtained: Varying the temperature of the milk above er below normal when measuring the portion for the tests; Using acid of unstandardized strength and incorrect temperature; Varying the temperature of reading the fat column above and below normal; Varying the speed of the centrifuge above or below the specified speed; Using test bottles that varied more than 0.015cc. from the correct capacity of 1.600 cc. in the calibrated portion. The following variations in the Babcock testing technique were found to have slight but noticeable effects on the final fat tests: Not using a proper lighting system to determine the exact position of the upper meniscus in reading the test; Adding water to the tests of such a temperature that the fat column migrated downward at least one inch in tempering at 138° F.; Using speeds of the centrifuge above that which was specified. Results of miscellaneous studies showed that: Duplicate tests by the Mojonnier method checked within an average variation of 0.0064 and a maximum variation of 0.015; Pasteurization of milk prevented the increased difference in results between the Babcock and Mojonnier methods of testing on samples stored for 15- days; Smaller differences were obtained on the same tests by different readers when read by the reading light than were obtained when the light was not used; Errors of 0.05 in reading the Babcock test were attributed to inability to determine the exact position of the top meniscus on the fat column; Dumping the milk in weigh vats at milk plants did not cause enough agitation to incorporate the cream sufficiently to obtain an accurate sample; Closer agreements were obtained with the Babcock and Mojonnier methods on the same sample of milk from Holstein and Ayrshire cows than were obtained on the milk from Jersey cows.
-
1234. [Article] Biological attributes and alteration of the habitat to manipulate populations of Labops hesperius Uhler (Heteroptera:Miridae)
Biological attributes and alteration of the habitat of Labops hesperius Uhler were investigated on rangeland seeded to crested wheatgrass near Vale, Oregon, and on rangeland seeded to crested and intermediate ...Citation Citation
- Title:
- Biological attributes and alteration of the habitat to manipulate populations of Labops hesperius Uhler (Heteroptera:Miridae)
- Author:
- Fuxa, James R.
Biological attributes and alteration of the habitat of Labops hesperius Uhler were investigated on rangeland seeded to crested wheatgrass near Vale, Oregon, and on rangeland seeded to crested and intermediate wheatgrass near Seneca, Oregon. Nymphs and adults were present at Vale from late March until mid-June and at Seneca from early April until late June or early July. Females at the Vale site preferred to oviposit in dry culms of crested wheatgrass and in Sandberg's bluegrass but they also oviposited in cheatgrass and green calms of crested wheatgrass. Females at a Seneca site oviposited in green intermediate wheatgrass. Population density at the Vale site was positively correlated with the total weight of dry wheatgrass and ground litter present at different locations because the straw provided oviposition sites or protection for the bugs. The obligatory egg diapause was investigated by subjecting eggs collected in September to different temperature treatments in the laboratory. Diapause was terminated after a minimum of 60 days exposure to 3° or 9° C and about two weeks incubation in 15°C and 16-hour photophase. Eggs survived temperatures as low as -15° C, and one temperature treatment resulted in 87% hatch. A 30 day acclimation temperature of 9° or 3° C before exposing the eggs to 3° or -15°C, respectively, resulted in a higher egg-hatch percentage. Egg diapause in L. hesperius differed from that in other mirids because the embryo of the former diapaused at a more advanced stage of embryogenesis. Sticky traps, pitfall traps, and a marking technique were used to study dispersal capabilities of L. hesperius at the Vale site. The bugs were capable of moving 7. 8 meters by walking on the ground and 23. 2 meters by a combination of flying and walking. The bugs could perceive red, yellow, and blue traps, but not white traps, at an altitude of 1. 52 meters, which was the common flight altitude. Macropterous females attained sexual maturity later than brachypterous females indicating that the former are specialized for migration. Males flew but the trap data did not indicate whether the nature of their flight was dispersal or trivial. The low percentage of macropterous females in the population might explain the slow dispersal rate of L. hesperius. Another mirid, Irbisia brachycera Uhler, was also captured in large numbers on sticky traps. Feeding damage to wheatgrass plants was studied by visual evaluation and chemical analysis of the damaged leaves. Chemical analysis indicated that feeding damage caused a decrease in plant cell contents but an increase in digestibility of the cell-wall constituents. However, a damage level of only 25% caused a relative increase in cell-wall constituents to an extent that would probably decrease the voluntary intake of wheatgrass by ruminants. Various range cultural and management practices were investigated to determine whether they could be used to reduce the population density of L. hesperius. Fertilizer treatments that included nitrogen significantly increased the density of L. hesperius but none of the fertilizer treatments significantly decreased the density. The bug density did not increase in proportion to the increase in herbage yield expected from fertilizing wheatgrass with nitrogen. The herbicide Paraquat indirectly killed nymphs and adults of L. hesperius by prematurely curing the wheatgrass which resulted in starvation of the bugs. The egg density was also reduced because the females starved to death before they were able to oviposit. Paraquat reduced the herbage yield as expected but increased the quality of the herbage. Prematurely curing wheatgrass with Paraquat will be an economical method of controlling L. hesperius provided that the spray can be timed to both reduce the bug population and increase the feed value of the forage. Mechanical removal of herbage during the egg stage reduced the bug population density by directly destroying the eggs or by exposing them to more harsh winter conditions or both. Mechanical removal during the nymphal and adult stages did not directly affect the population density since the bugs were able to find sufficient food for survival in the stubble. However, mechanical removal of herbage during the nymphal stages can reduce bug density in populations that are relatively dense originally, and removal immediately before oviposition prevents the females from laying eggs. Field burning, hay crop removal, and grazing are cultural practices that might control L. hesperius by mechanically removing the herbage. Hay crop removal, grazing during the nymphal and early adult stages, and grazing during the egg stage should each prove useful for controlling L. hesperius on different types of pasture infested with bugs.
-
1235. [Article] Characterization of microaggregate formation by Mycobacterium avium subspecies hominissuis
Mycobacterium avium subsp hominissuis (MAH) is an opportunistic environmental pathogen that causes respiratory and gastrointestinal illness in immunocompromised persons such as those with chronic respiratory ...Citation Citation
- Title:
- Characterization of microaggregate formation by Mycobacterium avium subspecies hominissuis
- Author:
- Babrak, Lmar
Mycobacterium avium subsp hominissuis (MAH) is an opportunistic environmental pathogen that causes respiratory and gastrointestinal illness in immunocompromised persons such as those with chronic respiratory diseases or AIDs, respectively. In recent years, there has been a significant increase in the incidence of nontuberculous mycobacterial (NTM) lung infections, including in cystic fibrosis patients where MAH accounts for 72% of mycobacterial infections. Currently, there is no efficient approach to prevent or treat MAH infection in the lungs. During initial colonization of the airways, MAH form microaggregates composed of 3 to 20 bacteria on the human respiratory epithelial cells, which provides an environment for phenotypic changes leading to efficient mucosal invasion in vitro and in vivo. In this dissertation, the aims are to identify and characterize genes that are important for the invasive microaggregate phenotype and characterize the host response to microaggregate infection to further understand the early stages of MAH respiratory infection. In Chapter 2, DNA microarray analysis was employed to identify genes associated with the microaggregate phenotype. The gene encoding microaggregate- binding protein 1 (MBP-1) (MAV_3013) is highly expressed during microaggregate formation. When expressed in noninvasive Mycobacterium smegmatis, MBP-1 increased the ability of the bacteria to bind to HEp-2 epithelial cells. Using anti-MBP- 1 immune serum, microaggregate binding to HEp-2 cells was significantly reduced. By far-Western blotting, and verified by coimmunoprecipitation, we observed that MBP-1 interacts with the host cytoskeletal protein vimentin. As visualized by confocal microscopy, microaggregates, as well as MBP-1, induced vimentin polymerization at the site of bacterium-host cell contact. Binding of microaggregates to HEp-2 cells was inhibited by treatment with an anti-vimentin antibody, suggesting that MBP-1 expression is important for M. avium subsp. hominissuis adherence to the host cell. MBP-1 immune serum significantly inhibited M. avium subsp. hominissuis infection throughout the respiratory tracts of mice. In Chapter 3, the small hypothetical gene MAV_0831 (Microaggregate Invasion Protein-1, MIP-1) was identified as being upregulated during microaggregate formation. When MIP-1 was overexpressed in poorly-invasive M. smegmatis, it provided the bacterium the ability to bind and enter epithelial cells. In addition, incubating microaggregates with recombinant MIP-1 protein enhanced the ability of microaggregates to invade HEp-2 cells, and exposure to anti-MIP-1 immune serum reduced the invasion of the host epithelium. Through protein-protein interaction assays, MIP-1 was found to bind to the host protein filamin A, a cytoskeletal actin-binding protein integral to the modulation of host cell shape and migration. As visualized by immunofluorescence, filamin A was able to co-localize with microaggregates and to a lesser extent planktonic bacteria. Invasion of HEp-2 cells by microaggregates and planktonic bacteria was also inhibited by the addition of anti-filamin A antibody suggesting that filamin A plays an important role during infection. In addition, at earlier time points binding and invasion assay results suggest that MBP-1 participates significantly during the first interactions with the host cell while MIP-1 becomes important once the bacteria adhere to the host epithelium. While these studies are valuable in understanding the pathogenesis of MAH, they primarily investigated the bacteria during microaggregate infection without commenting on the differences in the host response to microaggregate and planktonic infection. In Chapter 4, the bacteria-host interaction between microaggregates and epithelial cells was examined in a variety of assays. Using a transwell polarized epithelial cell model, microaggregates tended to translocate through the monolayer more efficiently than planktonic bacteria. In addition, during infection with microaggregate and planktonic bacteria, host phosphorylated proteins were identified revealing differences in immune response, glutathione synthesis, and apoptosis. The host immune response was further investigated by measuring pro-inflammatory cytokine secretion during microaggregate and planktonic infection of BEAS-2B bronchial epithelial cells. The epithelial cells secreted more CCL5 during microaggregate infection suggesting that this chemokine may play an important role during microaggregate invasion. Collectively, this study confirms the different nature of infection by planktonic bacteria and microaggregates. Overall, our data provide insights into the initial interaction between MAH and the respiratory mucosa. We characterized a pathogenic mechanism of infection utilized by MAH to manipulate the host respiratory epithelium and suggest new potential targets for the development of anti-virulence therapy.
-
1236. [Article] Carboxylesterases in the house fly (Musca domestica, L.), flesh fly (Sarcophaga bullata, Park.), and black blow fly (Phormia regina, Meig.)
The carboxylesterases of three species of diptera, the flesh fly (Sarcophaga bullata, Park.), the black blow fly (Phormia regina, Meig.), and the house fly (Musca domestica, L.) were compared in relation to ...Citation Citation
- Title:
- Carboxylesterases in the house fly (Musca domestica, L.), flesh fly (Sarcophaga bullata, Park.), and black blow fly (Phormia regina, Meig.)
- Author:
- Maa, Can-jen William
The carboxylesterases of three species of diptera, the flesh fly (Sarcophaga bullata, Park.), the black blow fly (Phormia regina, Meig.), and the house fly (Musca domestica, L.) were compared in relation to hydrolytic activity against three substrates, response to inhibition and induction, isozyme composition, and age-dependent variation in activity. Similar studies were also conducted with an insecticide-resistant house fly strain. Most of the experiments were with adult female flies but male flies as well as larvae and pupae were included in several experiments. Naphthyl acetate was the substrate common to all experiments and the esterases hydrolyzing this compound were further characterized according to their inhibition by eserine, parahydroxymecuribenzoate (PHNB), and paraoxon. The hydrolytic activity observed in the presence of eserine and PHNB or blocked by paraoxon was considered to be due to carboxylesterases of the B-type. Two other esters, hydroprene, an insect growth regulator similar in structure to the natural juvenile hormone, and juvenile hormone-1, were also used as substrates. Neither the hemolymph nor the cytosol esterases of the three species were susceptible to eserine inhibition, indicating that the samples contained minor quantities of the choline esterases. PHNB had little inhibitory effect on the flesh fly esterases of both hemolymph and soluble fraction. However, this inhibitor reduced the activity of the blow fly esterases by more than 50 percent, indicating a high content of aryl esterases in this species. The house fly esterases were also inhibited by PHNB but to a less extent than those of the blow fly. As expected, paraoxon was a strong inhibitor of the esterases in both hemolymph and soluble fraction of the three species. The total enzyme content of the flies was estimated from the hemolymph volumes determined earlier and the activity per unit volume found in the age-dependency experiments. The daily average activity estimated in this way was highest in the flesh fly, about four times that of the blow fly, and lowest in the house fly, about one-seventh that of the flesh fly. The values were even lower in the case of the resistant house flies, about 1/40th those of the flesh fly. When hydroprene was used as a substrate in the age-dependency experiments, the activity profiles were similar to those found with naphthyl acetate as substrate indicating that the same enzymes were involved in the hydrolysis of this JH analogue. Of the three species, the flesh fly esterases were most active against hydroprene and the blow fly and resistant house fly enzymes were the least active. The flesh fly hemolymph enzymes averaged, on a per-day basis, up to three times more hydroprene cleaving activity than those of the resistant house flies. The electrophorese experiments with hemolymph and cytosol revealed the presence of several carboxylesterase isozymes. As many as 14 different esterase-active bands were found in flesh fly hemolymph, 11 in blow fly hemolymph, and 12 in house fly hemolymph. Similar results were obtained with the cytosol. These bands were placed in five groups according to their mobilities in the poly acrylamide gels and it was evident that the isozymes migrating to the midpoint of the gels were responsible for most of the carboxylesterase activity. Some slow-moving isozymes were also thought to be responsible for this type of activity. Other evidence obtained during the electrophoreses experiments indicated that the isozymes hydrolizing hydroprene were from the same groups as those cleaving naphthyl-acetate while those which attacked JH-1 had different electrophoretic characteristics. Both hydroprene and naphthyl acetate esterases were induced by topically applied hydroprene. The response was dose dependent in the range 1-10 ug for flesh flies and 1-5 ug for house flies and blow flies. However, the response was variable and appeared to depend on the age of the flies at the time of the treatment. Increases in esterase activity ranged from 1.5 to 4-fold with the flesh fly enzymes being the most responsive and those of the blow fly the least. The possibility of JH-1 esterase induction by hydroprene was not investigated.
-
1237. [Article] Transcription factor CTIP2 regulates hair follicle development, hair cycling and wound healing
The integumentary system is the largest organ system of the body that comprises of skin and its appendages such as hair follicles, sebaceous and sweat glands. Skin is divided into three distinct structural ...Citation Citation
- Title:
- Transcription factor CTIP2 regulates hair follicle development, hair cycling and wound healing
- Author:
- Bhattacharya, Shreya
The integumentary system is the largest organ system of the body that comprises of skin and its appendages such as hair follicles, sebaceous and sweat glands. Skin is divided into three distinct structural layers: the epidermis, dermis and hypodermis. The epidermis originates from the ectoderm and is composed of four layers specified as basal, spinous, granular and corneal layer. The function of epidermis is to protect against all sources of environmental insults, prevent water loss and undergo re-epithelialization after wounding. For its normal functioning, the epidermis continually replenishes itself through a process of continuous proliferation and terminal differentiation of keratinocytes from the basal layer. The hair follicle is a complex appendage of skin, which give rise to the keratinized hair shaft. Hair follicle is formed during embryonic development and it goes through cycles of growth (anagen), regression (catagen) and quiescence (telogen). The bulge region of the hair follicle in the outer root sheath area contains slow-cycling stem cells which are responsible for normal hair cycling as well as cutaneous wound repair after injury. CTIP2 (COUP-TF interacting protein 2) is a C2H2 zinc finger transcription factor that is expressed in various organs and tissues. It has been shown to play an important role in the development of thymocyte, tooth and corticospinal motor neuron. Expression of CTIP2 is observed in the developing murine epidermis and dermis during skin organogenesis and predominantly in epidermal keratinocytes in adult mice skin. It is also expressed in the embryonic and mature adult hair follicles, especially in bulge region. CTIP2 regulates epidermal proliferation and terminal differentiation during embryogenesis and adulthood. Here we show that CTIP2 controls hair follicle development, hair cycling and cutaneous wound healing. To study the role of CTIP2 in hair morphogenesis and hair cycling, we have utilized two different genetically modified mouse strains. First, we studied the effect of CTIP2 during hair follicle formation using Ctip2-null mice containing a germline deletion of Ctip2. Ctip2-null mice exhibited reduced hair follicle density and downregulation of EGFR and NOTCH1 expression. To analyze the consequence of loss-of–funtion of CTIP2 on postnatal hair cycling, we selectively ablated Ctip2 in the epidermis and hair follicles using the Cre-LoxP strategy to generate Ctip2[superscript ep-/-] mice. Ctip2[superscript ep-/-] mice showed a defect in postnatal hair cycling marked by early exit from telogen and premature entry into anagen. The premature induction of anagen is a result of stem cell activation, increase in cell proliferation and decrease in apoptosis-driven cell death in the hair follicles. This early activation of follicular stem cells eventually leads to their depletion and therefore ultimate loss of hair follicles and hair coat. Reduced expression of LHX2 and NFATC1, which are two important regulators of hair cycling, was observed in the bulge area of Ctip2[superscript ep-/-] mice hair follicles. Furthermore, chromatin immunoprecipitation (ChIP) assay revealed that CTIP2 is recruited to the promoter region of both Lhx2 and Nfatc1 and possibly directly regulates their expression. Altogether, our results suggest that CTIP2 modulates expression of factors that regulate hair follicle morphogenesis and normal hair cycling as well as control stem cell fate and survival in the HFs. Considering CTIP2’s role in skin formation and homeostasis we hypothesized that CTIP2 is involved in the epidermal regeneration process during wound closure after injury. To test our hypothesis, we used Ctip2[superscript ep-/-] mouse model where Ctip2 is conditionally inactivated in epidermis and hair follicle. Selective ablation of Ctip2 in the epidermis and HFs lead to the delay in wound healing. The slower healing property was an outcome of impaired keratinocyte activation, proliferation, differentiation and migration. Moreover, defects in cell-cell adhesion and ECM development were also observed in the healing wounds of Ctip2ep-/- mice due to the lack of E-cadherin and insufficient expression of alpha smooth muscle actin. Hair follicle stem cell factors such as K15, CD34, CD133, NFATC1 and LRIG1 that are crucial for wound re-epithelialization were aberrantly expressed in wound adjacent region of Ctip2[superscript ep-/-] mice. Our results identify CTIP2 as a key regulator of epidermal stem cells during skin wound healing and an important player in efficient wound closure after injury.
-
Abstract -- Task 1.1: Distribution, Abundance, and Proportion of Hatchery and Natural-Origin Chinook Salmon: Counts of spring Chinook redds were similar in 2010 compared to the 2002–2009 averages for the ...
Citation Citation
- Title:
- Willamette Biological Opinion Hatchery Research 2010 Annual Report
Abstract -- Task 1.1: Distribution, Abundance, and Proportion of Hatchery and Natural-Origin Chinook Salmon: Counts of spring Chinook redds were similar in 2010 compared to the 2002–2009 averages for the Middle Fork Willamette, McKenzie and the North Santiam rivers and significantly higher in the South Santiam River Preliminary analyses indicate that the proportions of hatchery fish recovered as carcasses from the spawning grounds varied significantly among all four surveyed sub-basins (South Santiam > M. Fork Willamette > North Santiam > McKenzie) Task 1.2: Monitor fin-clipped & unclipped fish passing Leaburg and Upper Bennett dams. Adult fish passage at Leaburg and Upper Bennett dams was continuously monitored in 2010. We estimated that 2,696 spring Chinook (52% unclipped) passed above Leaburg Dam and 5,956 passed above upper Bennett Dam (14% unclipped). Passage at Leaburg Dam of fin-clipped fish was strongly bimodal with peaks in June (coincident with passage of the majority of unclipped fish) and September (coincident with a smaller proportion of unclipped fish). This bimodal peak suggests that hatchery fish might be removed in September to reduce the proportion of hatchery origin spawners while simultaneously reducing the impacts of handling wild fish. Task 2.1: Collection, spawn timing, and Hatchery/Wild (H/W ) composition for broodstock management. Collection, spawn timing, and H/W composition for broodstock management were successfully monitored at all facilities in 2010. Task 2.2: Determine Survival of Outplanted Fish and Abundance of Spawners. Patterns of pre-spawning mortality were similar to results in 2009 with mortality below project dams significantly higher than that above project dams. We did not detect significant differences in mortality between clipped and unclipped spring Chinook. In comparisons of pre-spawning mortality among sub-basins above project dams, pre-spawning mortality was uniformly low in the Breitenbush and N. Santiam above Detroit, S. Santiam above Foster, and in the S. Fork McKenzie. Pre-spawning mortality was uniformly higher above project dams in the N. Fork Mid. Fork Willamette, Fall Creek and the Little N. Fork Santiam. No comprehensive surveys were conducted in the Middle Fork Willamette. Task 3.1: Determine the extent of summer steelhead reproduction in the wild: We developed a formal study plan to analyze and interpret genetic results from a collection of 299 tissue samples from unclipped juvenile steelhead at Willamette Falls, five from the mainstem Willamette River, and two from the South Santiam River in 2010 in addition to a single sample from an unclipped adult steelhead at the Minto fish collection facility. Samples were preserved 7 and cataloged and then shipped to the NOAA Fisheries Manchester, Washington (WA) laboratory for analysis. Task 3.2: Evaluate release strategies for summer steelhead to increase migration and reduce impacts on wild fish. Study plans to evaluate advantages and disadvantages of volitional release strategies were completed and presented in the 2009 annual report to USACE (Cannon et al. 2010). Funding to process the tissue samples was not available in 2010, and no progress was made in executing the proposed work.
-
1239. [Article] Recovery of Wild Coho Salmon in Salmon River Basin, 2008 Report Number: OPSW-ODFW-2009-10
Abstract -- Recovery and conservation of naturally self-sustaining salmon populations is a central goal of the Oregon Plan for Salmon and Watersheds. In 1998, the Oregon Department of Fish and Wildlife ...Citation Citation
- Title:
- Recovery of Wild Coho Salmon in Salmon River Basin, 2008 Report Number: OPSW-ODFW-2009-10
Abstract -- Recovery and conservation of naturally self-sustaining salmon populations is a central goal of the Oregon Plan for Salmon and Watersheds. In 1998, the Oregon Department of Fish and Wildlife (ODFW) initiated a comprehensive program to monitor the status of coho salmon (Oncorhynchus kisutch) populations and aquatic habitat in coastal drainages of Oregon (OWEB 2003). A 2005 assessment by ODFW concluded that Oregon coastal coho were viable at the scale of the Evolutionary Significant Unit (ESU) and demonstrated resilience in response to improving ocean conditions. Yet 7 of 21 (33%) individual populations within the ESU failed one or more of five criteria used to assess viability (Chilcote et al. 2005), and it is uncertain whether productivity levels across the ESU will recover sufficiently to withstand future periods of poor ocean conditions. The coho population in Salmon River was the only population in the ESU to fail all five viability criteria. Uncertainty remains about the response of Oregon coastal coho salmon to different combinations of freshwater and marine limiting factors, complicating recovery efforts (Lawson 1993; Lawson et al. 2004; IMST 2006). Such uncertainty cannot be resolved entirely by existing Oregon Plan monitoring programs, which target only a portion of the habitats and coho salmon life stages in large river basins, and with few exceptions (e.g., Johnson et al. 2005), were not designed to test population responses to individual management manipulations. In 2007, in response to the failure of viability criteria, ODFW managers discontinued releases of hatchery coho salmon into Salmon River as one of the primary management actions under the Oregon Conservation Plan for the Oregon Coast Coho Evolutionarily Significant Unit (hereafter “coho plan,” Nicholas 2006). This change affords the first opportunity in Oregon to monitor the results of a large scale experiment in removing hatchery coho salmon from a basin for at least four generations (twelve years). Hatchery production has been a centerpiece of salmon management for decades, but rarely has full recovery from hatchery influence been given a chance to succeed. Salmon River offers a test basin to explore whether an independent population of coho salmon can recover from a prolonged period of very low abundance following removal of the primary factor limiting productivity. Here we describe the first year of a study to monitor the dynamics of the coho salmon population in the Salmon River basin on the central Oregon coast and to determine whether management changes targeting both hatchery influence and stream habitat complexity improve population viability. This research will validate assumptions about factors limiting coho recovery and determine whether recovery measures proposed by the Coho Plan have been effective. Our research is designed to document changes in population abundance, distribution, and life history structure of coho salmon following the removal of hatchery coho salmon from the watershed. It integrates adult, juvenile, and habitat components to establish links and describe variability between juvenile performance and adult recovery. It also monitors the coho salmon population across habitat types and life history stages to identify population responses at a landscape scale. We will establish the link between productivity and survival at each salmon life stage and recovery of the adult population. From these indicators, we will determine the potential resiliency of coho salmon, detail the biological benefits/tradeoffs of returning the ecosystem to natural salmon production, and assess whether supplementation should remain an option in Salmon River. As a conceptual framework, our research design and analyses are guided by the “viable salmonid population” criteria identified by McElhany (2000) and modified by Chilcote et al. (2005) and Nicholas (2006), including abundance, productivity, distribution, diversity, and habitat quality. The results of our new research will be integrated with habitat survey and adult population data collected under the existing Oregon Plan monitoring program and coho salmon population and life history data available from previous Salmon River surveys (Mullen 1978, 1979; Cornwell et al. 2001; Bottom et al 2005; Volk et al. in review). Together these data will address four principal objectives: 1. Quantify viability of the coho salmon population before and after hatchery coho salmon are removed from Salmon River. 2. Assess whether viability of the Salmon River coho population is limited by quantity and complexity of stream habitat. 3. Describe the diversity of juvenile and adult life histories of coho salmon in the Salmon River basin and estimate the relative contributions of alternate juvenile life history to adult returns. 4. Determine salmonid use and benefits of restored tidal wetlands before and after hatchery coho salmon are removed from Salmon River. By synthesizing historic data with new information for the Salmon River basin, we will compare population structure during three distinct periods – pre-hatchery (1974-77), hatchery (1990-2008), and post-hatchery (2009-2013). This annual report discusses the activities and findings from 2008, the first year of the multi-year project, including coho salmon distribution and abundance on the Salmon River spawning grounds, juvenile abundance and distribution in the watershed and estuary, migration timing, and life history diversity.
-
Part 1 The concentration of seventeen elements in two species of fungus which cause wheat bunt disease, Tilletia caries (DC.)Tul. (TS) and Tilletia controversa Kiihn (DS), were determined by instrumental ...
Citation Citation
- Title:
- Chemical element profiles by instrumental neutron activation analysis : in, part 1, two species of wheat bunt spores, Tilletia caries (DC) Tul. and Tilletia controversa Kühn; part 2, representative sediment and basalt samples taken from a DSDP 678 m core, site 525A, Leg 74, Walvis Ridge
- Author:
- Liu, Yun-gang
Part 1 The concentration of seventeen elements in two species of fungus which cause wheat bunt disease, Tilletia caries (DC.)Tul. (TS) and Tilletia controversa Kiihn (DS), were determined by instrumental neutron activation analysis in 37 TS spore samples, and 31 DS spore samples. Aluminum was chosen as a soil contamination indicator to correct for soil contamination. The plot of the concentrations of the ith element [X[subscript i]] versus Al, yielded the biological concentrations of [X.[subscript i]]. The results show that the biological concentrations of Sc, V, La, and Sm are insignificantly small and that their contents in the spores are essentially all derived from soil dust contamination. For Na and Fe, considerable fractions, 0.15 and 0.60, respectively, of their total concentrations are derived from soil contamination. For other elements, the soil contamination contributions are relatively small compared to their biological concentrations. The "student" t-test was used for comparisons of the geometric means of the element concentrations between the TS and DS spore series. The differences between the mean values of Cl, K, Ca, Mn, Zn, and Br for the TS and CS series are not totally due to random errors within the 95% confidence level. The differences for K and Cl between the TS and DS series are large and outside the ±10- limits; therefore, the concentrations of these two elements can be used as reliable criteria for distinguishing these two species. Also, Br may be useful as a diagnostic trace element due to the significant difference between the Br geometric means of the TS and DS spores. Part 2 Forty sediment and four basement basalt samples, taken from a 678 m core drilled by the DSDP (Deep Sea Drilling Project) at Site 525A, Leg 74 (June 10-15, 1980), as well as sixteen selected basalt samples around the south Atlantic Ocean were subjected to instrumental neutron activation analysis. Thirty-two major, minor, and trace elements were determined. The core from the Wavlis Ridge site (2467 m) consisted of 574.6 m of sediment and 103.5 m of basalt. The downcore element concentration profiles and regression analyses show that the rare earth elements (REE) are present in significant amounts in both the carbonate and non-carbonate phases in sediments; Sr is concentrated in the carbonate phase; most of the other elements determined exist mainly in the non-carbonate (mostly clay) phase. The calculated partition coefficients of the REEs between the carbonate phase and the free REE ion concentrations in sea water were high and increased with decreasing REE ionic radii or increasing atomic number from 3.9x10⁶ for La to 15x10⁶ for Lu. Using the partition coefficients of the REEs in the carbonate and non-carbonate (clay) phases, the REE concentrations in Atlantic sea water were calculated, and the results indicate that the lanthanide concentrations have not been changed significantly in south Atlantic sea water over the past 70 m.y.. The Ce anomaly observed in >95% carbonate sediments is related to the Ce⁺³ concentration in sea water; therefore, the Ce anomaly is a redox (reducing-oxidizing) indicator of sea water. (Essentially, >99.99% of soluble Ce in sea water is present as Ce⁺³.) The REE patterns show no Ce depletion in mollusc shell segments from the late Campanian, and a slight Ce depletion in carbonate phases from the late Paleocene sediments. From early Eocene on, the REE patterns in the carbonate phase show a marked Ce depletion, the same as is observed in carbonates from the late Pleistocene to early Holocene (about 0.3 m.y. ago). The abrupt and striking change in the Ce depletion indicates that sea water was anoxic over the Walvis Ridge during the late Campanian. As the gap between northeast South America (northeast Brazil) and west central Africa (near the southwest corner of the upper half of Africa, e.g., near Liberia) widened and the Walvis Ridge subsided between the late Campanian and late Paleocene, sea water flow between the north Atlantic and south Atlantic oceans increased steadily, and gradually flushed out the anoxic water layer over the Walvis Ridge, thereby achieving oxidation conditions at about 54 m.y. ago, that are similar to present day sea water redox conditions: in the world oceans. The chemical compositions of the basement rocks of the core corresponds to alkalic basalts, not MA-Crean Ridge basalts (MORBs). Only a few basement rocks had been recovered from other Walvis Ridge sites. The results add more evidence which supports the hypothesis that the Wavlis Ridge was formed by a series of volcanoes moving over a "hot spot" near the Mid-Atlantic Ridge. These volcanoes migrated eastward as the South American and African continents drifted away. Most of the basalt samples taken from the southeast Brazilian continental margin also are not similar to MORE. From the bulk chemical composition and the REE pattern, one 112 m.y. old basalt has been identified as an early-stage MORB. To date, this is the oldest oceanic tholeiite recovered from the south Atlantic. This direct evidence indicates that the continental split between South America and Africa commenced ≥112 m.y. ago, and is consistent with the suggestion that the rift between the two continents began about 125 m.y. ago.