Domoic acid exposure and associated clinical signs and histopathology in Pacific harbor seals (Phoca vitulina richardii)

Domoic acid (DA) is a potent neurotoxin that has caused strandings and mortality of seabirds and marine mammals off the California coast. Pacific harbor seals (Phoca vitulina richardii) are an abundant, nearshore species in California; however, DA exposure and toxicosis have not been documented for harbor seals in this region. To investigate DA exposure in harbor seals, samples were collected from free-ranging and stranded seals off California to assess exposure, clinical signs of toxicosis, and brain lesions in harbor seals exposed to DA. Domoic acid was detected in 65% (17/26) of urine samples collected from apparently healthy free-ranging seals, with concentrations of 0.4–11.7 ng/ml. Domoic acid also was detected in feces (2.4–2887 ng/g), stomach contents (1.4 ng/g; stranded only), milk (2.2 ng/ml; stranded only), amniotic fluid (9.7 ng/ml; free-ranging only), fetal meconium (14.6–39.8 ng/g), and fetal urine (2.0–10.2 ng/ml). Clinical signs indicative of DA toxicosis were observed in two live-stranded seals, and included disorientation, seizures, and uncoordinated movements. Histopathology revealed the presence of brain lesions consistent with DA toxicosis in two live-stranded seals, and one free-ranging seal that died during capture. Results indicated that harbor seals were exposed to DA, exhibited clinical signs and histological lesions associated with DA exposure, and that pups were exposed to DA in utero and during lactation via milk. Future investigation is required to determine the magnitude of impact that DA has on the health and mortality of harbor seals.     

Serum Retinol,alpha‐tocopherol,and lipids in four species of adult captive pinnipeds

The sera of adult aquarium‐held pinnipeds from four species (family Phocidae: harbor seals (Phoca vitulina) and gray seals (Halichoerus grypus); family Otariidae: northern fur seals (Callorhinus ursinus) and California sea lions (Zalophus californianus)) were analyzed for vitamin A (retinol), vitamin E (α‐tocopherol), total cholesterol, triglycerides, phospholipids, and fatty acids. Each subject animal was healthy at the time of blood collection, was fasted for at least 12 hr prior to sampling, and was maintained on a constant diet and supplement regime throughout the study. Retinol values for the four species ranged from 0.16 to 0.92 μg/mL, with the lowest concentrations seen in the harbor seals and the highest in the northern fur seals. Vitamin E values ranged from 10.55 to 43.58 μg/mL, with northern fur seals showing the highest and gray seals the lowest levels. Vitamin E/lipid ratios (cholesterol, triglyceride, phospholipid, and total lipids) were also examined. A significant correlation was seen between vitamin E and total lipids (P<0.05) and phospholipid (P<0.01). Statistical analysis of the retinol, tocopherol, triglyceride, and phospholipid levels showed significant differences between phocid and otariid seals. Otariids had significantly lower tocopherol and phospholipid values (19.36 μg/mL, 4.29 mg/mL) and the phocids had significantly lower retinol and triglyceride levels (0.29 μg/mL, 124 mg/dL). There was no significant difference in serum cholesterol. Zoo Biol 22:83–96, 2003. © 2003 Wiley‐Liss, Inc.     

Large‐scale molecular barcoding of prey DNA reveals predictors of intrapopulation feeding diversity in a marine predator

Predator–prey interactions are critical in understanding how communities function. However, we need to describe intraspecific variation in diet to accurately depict those interactions. Harbor seals (Phoca vitulina) are an abundant marine predator that prey on species of conservation concern. We estimated intrapopulation feeding diversity (variation in feeding habits between individuals of the same species) of harbor seals in the Salish Sea. Estimates of feeding diversity were examined relative to sex, month, and location using a novel approach that combined molecular techniques, repeated cross‐sectional sampling of scat, and a specialization metric (within‐individual consistency in diet measured by the Proportional Similarity Index ()). Based on 1,083 scat samples collected from five haul‐out sites during four nonsequential years, we quantified diet using metabarcoding techniques and determined the sex of the scat depositor using a molecular assay. Results suggest that intrapopulation feeding diversity was present. Specialization was high over short periods (24–48 hr,  = 0.392, 95% CI = 0.013, R = 100,000) and variable in time and space. Females showed more specialization than males, particularly during summer and fall. Additionally, demersal and benthic prey species were correlated with more specialized diets. The latter finding suggests that this type of prey likely requires specific foraging strategies and that there are trade‐offs between pelagic and benthic foraging styles for harbor seals. This differential feeding on prey species, as well as between sexes of harbor seals, indicates that predator–prey interactions in harbor seals are complex and that each sex may have a different impact on species of conservation concern. As such, describing intrapopulation feeding diversity may unravel hitherto unknown complex predator–prey interactions in the community.     

Effect of daptomycin on primary rat muscle cell cultures in vitro

Daptomycin is a lipopeptide antibiotic that has strong bactericidal activity against Gram-positive bacteria and that was previously reported to exhibit minor side effects on skeletal muscle. This study was designed to further characterize the effect of daptomycin on skeletal muscle through the use of primary cultures of muscles from rats. Our investigations demonstrated that daptomycin has a concentration-dependent and time-dependent effect on the plasma membrane of primary cultures of differentiated, spontaneously contracting rat myotubes. No effects were evident in non-differentiated myoblasts or other mononucleated cells present in cultures even at the highest daptomycin concentrations tested (6,000 μg/mL). In cultures treated with daptomycin at a concentration of 2,000 μg/mL, plasma membrane damage was observed in ∼20–30% of differentiated myotubes; no myotube damage was detected at concentrations of 1,000 μg/mL and below. A transient loss of spontaneous myotube contractions was evident at 750 μg/mL, while at 2,000 μg/mL and above, a permanent loss of spontaneous contractility was observed. These results suggest that the putative targets for daptomycin effects on skeletal muscle are structures on the plasma membrane of highly differentiated myotubes.     

Postrelease movement of rehabilitated harbor seal (Phoca vitulina richardii) pups compared with cohort‐matched wild seal pups

Harbor seal (Phoca vitulina richardii) populations in the inland waters of Washington and British Columbia are at or near carrying capacity. Stranded pups often are collected and admitted to rehabilitation centers, and then released when they reach a weight of 22 kg and meet a variety of preestablished health and release conditions. While rehabilitation is common practice, it is unclear if rehabilitated seal pups behave like wild weaned pups. Using satellite transmitters, we compared movement patterns of 10 rehabilitated pups with 10 wild weaned pups. When released, rehabilitated seals were longer and heavier than wild pups, while wild pups had a larger mean axillary girth. No clinically different blood parameters were detected. On average, rehabilitated harbor seal pups traveled nearly twice as far cumulatively, almost three times as far daily, and dispersed over three times as far from the release site compared to wild weaned seals. Additionally, wild harbor seals transmitted nearly twice as long as did rehabilitated seals. These patterns suggest that learned behavior during the brief 3–4 wk nursing period likely enables wild harbor seal pups to move less daily and remain closer to their weaning site than rehabilitated pups.     

Plasma gossypol dynamics in white-tailed deer: Implications for whole cottonseed as a supplemental feed

Whole cottonseed (WCS) is a potential supplemental feed for white-tailed deer (Odocoileus virginianus) in rangeland conditions because of its high digestible energy and protein content, moderate fiber content, and resistance to degradation in moist conditions. WCS also contains the polyphenolic secondary metabolite gossypol, which reduces palatability to non-target monogastric species but may be of concern for deer nutrition. Plasma gossypol stabilization when fed a constant dry matter intake, plasma gossypol depletion after WCS was removed from the diet, and the relationship between WCS consumption and plasma gossypol concentration was studied in 10 mature male (N = 5) and female (N = 5) captive white-tailed deer. Consumption of WCS by 73 free-ranging white-tailed deer (59 males, 14 females) was estimated using results of the captive study. Plasma gossypol concentrations declined exponentially and averaged 0.74 μg/mL 35 days after WCS was removed from the diet. Plasma gossypol concentration was linearly related to WCS consumption (P < 0.001), with females having 0.35 μg/mL greater (P = 0.04) plasma gossypol than males for a given rate of dry matter consumption. All female and 93% of male white-tailed deer captured in WCS supplemented pastures had detectable plasma gossypol. Female averaged 1.88 μg/mL of plasma gossypol and males averaged 4.84 μg/mL of plasma gossypol. Based on the captive deer data, these plasma values suggest an average WCS consumption of ∼2.6 g/kg BW/day for female free-ranging deer and ∼5.6 g/kg BW/day for male free-ranging deer. Inferentially, a large proportion of free-ranging white-tailed deer in rangeland conditions will consume WCS, with females consuming 125 g WCS/day and males consuming 428 g WCS/day. That plasma gossypol levels decrease rapidly after cottonseed is removed from the diet suggests that the long withdrawal periods often used prior to breeding season may not be needed. However, although 93% of gossypol was eliminated from the animals after a five-week withdrawal period, a small amount of gossypol can still be detected. While our preliminary data on these animals suggests that these levels are not detriment to animal health or reproduction, ranch managers may want to take a conservative approach to the feeding of WCS until these questions are answered.     

Possible involvement of corticosterone and serotonin in antidepressant and antianxiety effects of chromium picolinate in chronic unpredictable mild stress induced depression and anxiety in rats

In the present study, we investigated the effects of chromium picolinate (CrP) on behavioural and biochemical parameters in chronic unpredictable mild stress (CUMS) induced depression and anxiety in rats. The normal and stressed male Swiss albino rats were administered CrP (8 and 16 μg/mL in drinking water), they received stressors for seven days (each day one stressor) and this cycle was repeated three times for 21 days. On 22nd day, behaviour assessments followed by biochemical estimations were conducted. The results showed that treatment of CrP produced significant antidepressant effect, which has been evidenced by decrease in immobility time in modified forced swimming test (FST) in chronic unpredictable mild stress (CUMS) induced depression in rats. In elevated plus maze (EPM), CrP (16 μg/mL) showed significant reduction in time spent in open arm. CrP (8 μg/mL and 16 μg/mL) also showed significant decrease in number of entries in open arm that shows antianxiety effect of CrP in CUMS rats. It was also found that CrP (8 and 16 μg/mL) significantly increased 5-HT concentration in the discrete regions of brain (cortex and cerebellum). On the other hand, the plasma corticosterone level was significantly decreased with CrP (16 μg/mL). The results suggested that increase in the concentration of 5-HT and decrease in plasma corticosterone levels could be responsible for improvement in symptoms of depression and anxiety in CUMS induced depression and anxiety in rats.     

Fine-Scale Variability in Harbor Seal Foraging Behavior

Understanding the variability of foraging behavior within a population of predators is important for determining their role in the ecosystem and how they may respond to future ecosystem changes. However, such variability has seldom been studied in harbor seals on a fine spatial scale (<30 km). We used a combination of standard and Bayesian generalized linear mixed models to explore how environmental variables influenced the dive behavior of harbor seals. Time-depth recorders were deployed on harbor seals from two haul-out sites in the Salish Sea in 2007 (n = 18) and 2008 (n = 11). Three behavioral bout types were classified from six dive types within each bout; however, one of these bout types was related to haul-out activity and was excluded from analyses. Deep foraging bouts (Type I) were the predominant type used throughout the study; however, variation in the use of bout types was observed relative to haul-out site, season, sex, and light (day/night). The proportional use of Type I and Type II (shallow foraging/traveling) bouts differed dramatically between haul-out sites, seasons, sexes, and whether it was day or night; individual variability between seals also contributed to the observed differences. We hypothesize that this variation in dive behavior was related to habitat or prey specialization by seals from different haul-out sites, or individual variability between seals in the study area. The results highlight the potential influence of habitat and specialization on the foraging behavior of harbor seals, and may help explain the variability in diet that is observed between different haul-out site groups in this population.     

Antibodies to phocine herpesvirus-1 are common in North American harbor seals (Phoca vitulina)

Phocine herpesvirus-1 (PhHV-1) has been associated with morbidity and high mortality in neonatal harbor seals (Phoca vitulina) along the Pacific coast of California (USA) and in northern Europe. Seals dying with PhHV-1 associated disease in California primarily have histopathologic evidence of adrenal necrosis or adrenalitis with herpesviral inclusion bodies. Little is known about prevalence of exposure to PhHV-1, modes of disease transmission, and viral pathogenesis in free-ranging harbor seal populations. To evaluate the prevalence in North America, 866 serum samples collected between 1994 and 2002 from harbor seals captured or stranded on the Pacific and Atlantic coasts of North America were assayed by enzyme linked immunosorbent assay (ELISA) for evidence of PhHV-1 exposure. Samples from three harbor seal age classes (pre-weaned, weaned, and subadults/adults) were obtained from each of four regions to compare exposure among sex, age class, and region. We found increasing prevalence with age as 37.5% of pre-weaned pups, 87.6% of weaned pups, and 99.0% of subadults and adults were seropositive. When accounting for age, no associations between seropositivity and sex or location of harbor seals were detected. These data indicate that PhHV-1 is endemic in the harbor seal populations of North America.     

Subjects with Low Plasma HDL Cholesterol Levels Are Characterized by an Inflammatory and Oxidative Phenotype

Background

Epidemiological studies have shown that low plasma levels of high-density lipoprotein (HDL) cholesterol are associated with increased risk of cardiovascular disease, but the mechanisms for the possible atheroprotective effects of HDL cholesterol have still not been fully clarified, in particular in relation to clinical studies.

Objective

To examine the inflammatory, anti-oxidative and metabolic phenotype of subjects with low plasma HDL cholesterol levels.

Methods and Results

Fifteen subjects with low HDL cholesterol levels (eleven males and four females) and 19 subjects with high HDL (three males and 16 females) were recruited. Low HDL cholesterol was defined as ≤10th age/sex specific percentile and high HDL-C was defined as ≥90 age/sex specific percentile. Inflammatory markers in circulation and PBMC gene expression of cholesterol efflux mediators were measured. Our main findings were: (i) subjects with low plasma HDL cholesterol levels were characterized by increased plasma levels of CRP, MMP-9, neopterin, CXCL16 and ICAM-1 as well as low plasma levels of adiponectin, suggesting an inflammatory phenotype; (ii) these individuals also had reduced paraoxonase (PON)1 activity in plasma and PON2 gene expression in peripheral blood mononuclear cells (PBMC) accompanied by increased plasma levels of oxidized LDL suggesting decreased anti-oxidative capacity; and (iii) PBMC from low HDL subjects also had decreased mRNA levels of ABCA1 and ABCG1, suggesting impaired reverse cholesterol transport.

Conclusion

Subjects with low plasma HDL cholesterol levels are characterized by an inflammatory and oxidative phenotype that could contribute to the increased risk of atherosclerotic disorders in these subjects with low HDL levels.     

Factors Affecting Haul-Out Behavior of Harbor Seals (Phoca vitulina) in Tidewater Glacier Inlets in Alaska: Can Tourism Vessels and Seals Coexist?

Large numbers of harbor seals (Phoca vitulina) use habitat in tidewater glaciers in Alaska for pupping, breeding, and molting. Glacial fjords are also popular tourist destinations; however, visitation by numerous vessels can result in disturbance of seals during critical life-history phases. We explored factors affecting haul-out behavior of harbor seals at a glacial site frequented by tourism vessels. In 2008-10, we deployed VHF transmitters on 107 seals in Endicott Arm, Alaska. We remotely monitored presence and haul-out behavior of tagged seals and documented vessel presence with time-lapse cameras. We evaluated the influence of environmental and physical factors on the probability of being hauled out, duration of haul-out bouts, and as factors associated with the start and end of a haulout. Location, season, hour, and interactions of location by year, season, hour, and sex significantly influenced haul-out probability, as did ice, weather, and vessels. Seals were more likely to be hauled out with greater ice availability during the middle of the day, and less likely to be hauled out if vessels were present. Cruise ships had the strongest negative effect; however, most vessel types negatively affected haul-out probability. Haul-out duration was longest in association with starting on incoming tides, clear skies, no precipitation, occurring in the middle of the day, and ending in the late afternoon or evening. End of haulouts was associated with increasing cloud cover, low ice availability, and vessel presence; large-sized tourism vessels or all-vessel-types combined were significant predictors of ending a haul-out bout. Probability of being hauled out was highest in June, during pupping season. Potential disturbances of harbor seals could be reduced, enabling longer resting times for seals and fewer interruptions for nursing pups, if vessels focused the majority of visits to glacial habitat to before or after the hours of 08:00-17:00 or, less optimally, 09:00-16:00.     

Serum insulin-like growth factor-I,iron, C-reactive protein,and serum amyloid A for prediction of outcome in dogs with pyometra

Pyometra, accumulation of pus in the uterus, is a bacterial infection that frequently initiates systemic inflammation. The disease may have lethal consequences when the systemic effects are severe or complications occur. Markers for identifying high-risk patients and predicting outcome are therefore in high demand. The objective of this study was to measure serum concentrations of insulin-like growth factor-I (IGF-I), iron, C-reactive protein (CRP), and serum amyloid A (SAA) in bitches with pyometra and to explore the possible value of these variables for detection of increased morbidity. In total, 31 bitches were diagnosed with pyometra and destined for surgical treatment (ovariohysterectomy) and 17 healthy bitches were included in the study. Concentrations of IGF-I and iron were lower in the pyometra group (mean concentration 221.2 ± 22.5 ng/mL and 16.9 ± 1.6 μmol/L, respectively) compared with the healthy control group (mean concentration 366.7 ± 46.2 ng/mL and 38.1 ± 2.7 μmol/L, respectively). In contrast, concentrations of CRP and SAA were significantly higher in bitches with pyometra (mean concentrations 212.9 ± 17.3 mg/L and 119.9 ± 8.5 mg/L, respectively) compared with the control group (<5 mg/L and <10 mg/L, respectively). None of the explored variables were associated with morbidity as measured by duration of postoperative hospitalization. In conclusion, IGF-I and iron concentrations were decreased in pyometra, whereas SAA and CRP concentrations were increased in the disease. Although unspecific, measurement of these variables may be valuable as adjunctive markers for prognosis in cases of pyometra.     

Movements and behavior of satellite-tagged spotted seals (Phoca largha) in the Bering and Chukchi Seas

Satellite-linked tags were attached to 12 spotted seals (Phoca largha) captured at a coastal lagoon in the eastern Chukchi Sea during August 1991–1993. Movements of seals were tracked for 32–298 days using the Argos system. Of 9,651 total location records obtained, 7,268 were usable. Individual seals were located on 41–96% of the days that tags were operational. During August–November, tagged seals alternated haul-outs at coastal sites lasting 1–304 h with trips to sea of 14–901 h. Coastal haul-outs occurred at 14 sites in western Alaska and eastern Russia. On several trips to sea, seals covered distances of more than 1,000 km. Movement southward from the Chukchi Sea generally began in October, with most of the seals passing through the Bering Strait during November. Seals first hauled out on sea ice in October (Chukchi Sea) or November (Bering Sea), and generally moved southward during October–December as sea-ice coverage increased. Seven seals, whose transmitters were still operating, spent December to June in the Bering Sea region between Kuskokwim Bay and Anadyr Gulf, which corresponded to the location of the ice front. The seals made active east-west movements within the ice front. Spotted seals are unlike other ice-breeding seals in that they regularly use coastal haul-outs during summer and autumn. Compared to the closely related Pacific harbor seal (Phoca vitulina richardsi), spotted seals make much longer trips to sea and spend longer continuous periods at their haul-outs during summer and autumn. Received: 9 April 1997 / Accepted: 30 September 1997     

Sickness-related odor communication signals as determinants of social behavior in rat: A role for inflammatory processes

Infected animals are avoided by conspecifics, suggesting that the inflammatory cascade may play a significant role in odor communication. Injection of male rats with the bacterial mimetic, lipopolysaccharide (LPS, 100 μg/kg, i.p.), decreased investigation through a wire-mesh partition between healthy male partners. This avoidance response was observed in adult males in response to soiled bedding collected from sick rats, regardless of whether LPS was injected peripherally (100 μg/kg, i.p.) or centrally (0.25 or 2.5 μg, icv). The release of sickness-related odor cues was dose-dependently blocked by icv infusion of the anti-inflammatory cytokine, interleukin-10 (IL-10; 20 or 200 ng), and reproduced by icv infusion of pro-inflammatory cytokine, IL-1β (5 or 50 ng). Subcutaneous pretreatment with either estradiol benzoate (20 μg/kg) or testosterone propionate (50 or 500 μg/kg) to adult males that were administered LPS inhibited release of aversive odor cues, but these hormones alone did not influence odor properties. Importantly, the avoidance response to sickness-related odor was not associated with changes in plasma corticosterone, testosterone, or IL-6 levels of odor donors. However, plasma IL-1β concentrations of sick animals was in fact predictive of aversive responses in conspecifics, suggesting that the inflammatory cascade, but not plasma steroid hormones, is likely to mediate aversive properties in odor that functions to signal illness state to conspecifics.     

Isolation and characterization of SAP and CRP,two pentraxins from Pangasianodon (Pangasius) hypophthalmus

From the serum of Pangasianodon hypophthalmus, two proteins were isolated by affinity chromatography on Sepharose and phosphorylcholine–Sepharose. Their binding on the affinity matrices critically depends on the presence of Ca²⁺ ions. N-terminal sequencing and sequencing of internal tryptic peptides identified the proteins as pentraxins and from their binding properties they are identified as SAP (serum amyloid P component) and CRP (C-reactive protein). Per ml serum, 36 μg SAP and 56 μg CRP was purified. Upon gel filtration, both the SAP and CRP elute as trimers of respectively 24 kDa and 28 kDa subunits. Both proteins are devoid of inter-chain disulfide bonds. Both SAP and CRP are glycosylated and agglutinate rabbit erythrocytes and pathogenic bacteria Edwardsiella ictaluri and Aeromonas hydrophila, but not Micrococcus lysodeikticus or Escherichia coli. Haemagglutination of SAP and CRP is inhibited by galactose (MIC = 1 mM) and by phosphorylcholine (MIC = 1–2 mM), respectively. Circular dichroism studies revealed that antiparallel β-pleated sheets are dominating the secondary structure. Upon removing the Ca²⁺ ions by EDTA, slight structural changes are observed by CD spectroscopy in the near-UV region. Immunodiffusion shows that P. hypophthalmus SAP and CRP do not cross-react.     

Effect of supplementation with Se-enriched yeast and factors influencing Se concentration in plasma of transplant recipients

The aim of this study was to assess the bioavailability of selenium (Se) in Se-enriched yeast and the possible impact of age, sex and area of residence on the Se concentration in plasma in 179 transplant recipients, as Se clinical effects in the prevention of cutaneous epithelial lesions in organ transplant recipients has been reported elsewhere. Subjects were randomized to receive either 200 μg Se/day (group 1:91 patients) or placebo (group 2: 88 patients) for 3 years. Plasma Se levels were measured at the beginning of the study and after 4, 12, 24 and 36 months of Se or placebo supplementation. Initial plasma Se levels were 90.9±26.1 μg/L for placebo and 94.0±25.3 μg/L for Se-supplemented groups. At baseline, the Se level was not linked to sex and age but to area of residence, although the number of subjects in each area was insufficient to draw any conclusions. Plasma Se levels were statistically lower in cases of liver transplant compared to kidney and heart transplant (p=0.03). Over the 3-year period of supplementation, plasma Se in the supplemented subjects was significantly higher than in the placebo group (p<0.01) and there was an interaction (p<0.01) between supplementation and time for plasma Se. Supplementation with Se-enriched yeast significantly increased the Se concentration in plasma of the patients to a plateau: the mean plasma Se of the Se-supplemented patients increased to 164.7±35.8 μg/L at 4 months and then remained similar at 12 (176.1±48.3 μg/L), 24 (176.1±54.2 μg/L) and 36 (182.2±46.4 μg/L) months.     

Extreme effects of Seabuckthorn extracts on influenza viruses and human cancer cells and correlation between flavonol glycosides and biological activities of extracts

Seabuckthorn is a medicinal plant that is used to prevent cold. It was tested for its metabolic content followed by activity against cancer and virus. The metabolic distribution of different polarity solvent extractions from the leaves was analyzed by LC–MS/MS. Flavonol glycoside contents in EA and Bu extracts were higher than MeOH and DW was observed. MeOH and EA extracts recorded high activity against influenza A/PR virus with IC₅₀ of 7.2 μg/mL and 10.3 μg/mL compared with known drug Oseltamivir of 60.3 μg/mL. A similar trend showed in influenza A/Victoria virus. In case of influenza B viruses such as B/Lee and B/Maryland, EA extract (2.87 μg/mL and 4.5 μg/mL of IC₅₀) emerged strongest among other extracts and Oseltamivir (103.73 μg/mL and 71.6 μg/mL). Each extract showed potent anticancer activities. Interestingly, Bu extract showed stronger anticancer activity against human cancer cells such as NCL-H1299, HeLa, SKOV and Caski (8.2 μg/mL, 8.6 μg/mL, 18.2 μg/mL and 9.2 μg/mL of IC₅₀) respectively. Correlation study reveals that aglycones and flavonol mono-glycosides highly correlated with anti-influenza activities but not correlated with anticancer activities. Reversely, di-glycosides and tri-glycosides have a high correlation with cytotoxic effect with both normal and cancer cells. Therefore, this study provides significant information concerning Seabuckthorn for further medicinal drug development.     

Food habits of harbor seals (Phoca vitulina richardii) as an indicator of invasive species in San Francisco Bay,California

The diet of harbor seals (Phoca vitulina richardii) in San Francisco Bay (SFB), California, was determined from July 2007 to July 2008 using prey hard parts recovered from 442 scats collected at five haul‐out sites. Twenty‐two species of fish and one species of crustacean were identified, but harbor seals primarily ate a nonnative invasive species, yellowfin goby (Acanthogobius flavimanus), which increased in dietary importance since the diet was last studied in 1991/1992. Additionally, another nonnative invasive fish species, chameleon goby (Tridentiger trigonocephalus), was found for the first time in the diet of harbor seals in SFB. Harbor seal diet was statistically different between years (1991/1992 and 2007/2008), between the pupping and nonpupping seasons, and between North SFB and South SFB haul‐out locations. The diet of harbor seals was significantly correlated with fish species caught in trawl surveys conducted by the California Department of Fish and Wildlife (CDFW) during the same time periods as this study (2007/2008). Harbor seals currently are influencing the health of the SFB ecosystem in a positive manner by consuming large quantities of nonnative invasive fish species.     

Bioanalytical method for the simultaneous determination of d- and l-serine in human plasma by LC/MS/MS

d-Serine is an endogenous modulator of N-methyl-d-aspartate (NMDA) receptors. Plasma concentrations of d-serine and the ratio of d-serine to total serine may be used as clinically-translatable biomarkers in NMDA receptor-related disease. We developed a highly sensitive and specific method using high performance liquid chromatography tandem mass spectrometry (LC/MS/MS) for the simultaneous determination of the d- and l-isomers of serine in human plasma. Since d- and l-serine are endogenous components, phosphate buffered saline was used as the surrogate matrix. d- and l-serine in human plasma and PBS were treated by cationic exchange solid phase extraction. d-Serine (m/z 106.1 > 60.0), l-serine (m/z 106.1 > 60.1) and dl-serine-d₃ (m/z 109.1 > 63.0) were detected using a multiple reaction monitoring. The enantiomer separation of d- and l-serine was successfully achieved without any derivatization step using tandemly-arranged and ice-cold CROWNPAK CR-I(+) columns with an isocratic mobile phase comprised of 0.3% trifluoroacetic acid in 10% acetonitrile. The standard curves were linear throughout the calibration range with 0.01–10 μg/mL (d-serine) and 0.1–100 μg/mL (l-serine), respectively. Intra-day and inter-day precision and accuracy of the quality control samples were within relative standard deviations of less than 15%. The endogenous concentrations of d- and l-serine in human plasma were 0.124–0.199 and 7.97–13.1 μg/mL, respectively.     

DIETARY AND SEASONAL INFLUENCES ON BLOOD CHEMISTRY AND HEMATOLOGY IN CAPTIVE HARBOR SEALS

It has become increasingly important to understand the relationship between dietary intake and blood chemistry and hematological profiles in pinniped populations, especially where nutritional stress has been implicated in population declines. Blood chemistry and hematology reference ranges have been commonly reported for both free‐ranging and captive harbor seals, but seasonal and dietary fluctuations are limited to only a few studies. We quantified changes in plasma metabolites and hematology values in captive harbor seals on different diets over two years. Of 29 blood chemistry and hematology variables examined in captive harbor seals, ALT, AST, GGT, creatinine, and BUN:creatinine were influenced by diet. BUN, Na⁺, Cl^?, Hct, and Hb were influenced by season. Diet did not affect hematology variables. While these data were collected on captive animals, we assume seasonal and dietary influences would be comparable in free‐ranging seals. According to this study, controlling for season during sampling becomes important when assessing blood chemistry values as an index of foraging status or health.