Mercury and selenium concentrations in lanugo of free-ranging California sea lions in the southern Gulf of California, Mexico.

Total mercury ([THg]) and selenium ([TSe]) concentrations were determined in California sea lion (Zalophus californianus) lanugo from the Gulf of California in 2021 and 2022. Relationships with sex, morphometrics, and year were evaluated. Following toxicological thresholds of concern for piscivorous mammals, most pups had a [THg] < 10 ppm, one pup (2021) had a [THg] > 20 ppm, no pups had a [THg] > 30 ppm. Females had significantly higher [TSe] than males; sex did not influence [THg]. [THg] and [TSe] in 2022 were significantly higher in the general population and male cohorts compared to 2021. Significant negative correlations were observed between [THg], [TSe], and morphometrics (2021). These results indicate that, compared to other pinniped species, regional California sea lions may have a decreased likelihood of experiencing Hg-related adverse health effects. Year-related changes in element concentrations suggest continued monitoring of this population to assess pinniped, environmental, and potentially, human health.

Comprehensive molecular and morphological resolution of blubber stratification in a deep-diving, fasting-adapted seal.

Blubber is a modified subcutaneous adipose tissue in marine mammals that provides energy storage, thermoregulation, hydrodynamic locomotion, and buoyancy. Blubber displays vertical stratification by lipid content, fatty acid composition, and vascularization, leading to the assumption that deeper blubber layers are metabolically active, while superficial layers are mainly structural and thermoregulatory. However, few studies have examined functional stratification of marine mammal blubber directly, especially in pinnipeds. We characterized morphological and transcriptional differences across blubber layers in the northern elephant seal, a deep-diving and fasting-adapted phocid. We collected blubber from seals early in their fasting period and divided blubber cores into three similarly sized portions. We hypothesized that the innermost blubber portion would have higher 1) heterogeneity in adipocyte size, 2) microvascular density, and 3) expression of genes associated with metabolism and hormone signaling than outer blubber. We found that adipocyte area and variance increased from outermost (skin-adjacent) to innermost (muscle-adjacent) blubber layers, suggesting that inner blubber has a higher capacity for lipid storage and turnover than outer blubber. Inner blubber had a higher proportion of CD144+ endothelial cells, suggesting higher microvascular density. In contrast, outer blubber had a higher proportion of CD4+ immune cells than inner blubber, suggesting higher capacity for response to tissue injury. Transcriptome analysis identified 61 genes that were differentially expressed between inner and outer blubber layers, many of which have not been studied previously in marine mammals. Based on known functions of these genes in other mammals, we suggest that inner blubber has potentially higher 1) adipogenic capacity, 2) cellular diversity, and 3) metabolic and neuroendocrine signaling activity, while outer blubber may have higher 1) extracellular matrix synthesis activity and 2) responsiveness to pathogens and cell stressors. We further characterized expression of nine genes of interest identified by transcriptomics and two adipokines with higher precision across blubber layers using targeted assays. Our study provides functional insights into stratification of blubber in marine mammals and a molecular key, including CD144, CD4, HMGCS2, GABRG2, HCAR2, and COL1A2, for distinguishing blubber layers for physiological and functional studies in seals.

Haemoparasites in endemic and non-endemic passerine birds from central Mexico highlands.

Haemosporidian parasites of birds are found worldwide and include the genera Haemoproteus, Plasmodium and Leucocytozoon. Infection with haemosporidian parasites can affect host physical condition and reproductive success. The aim of this study was to identify the blood parasites and parasitaemia in endemic and non-endemic passerine birds from central Mexico highlands. This study included 157 passerines representing 29 species from 17 families. Overall, 30.6% (48/157) of the birds were infected with blood parasites. Of those, Haemoproteus spp. were found in 14.0% (n = 22), Leucocytozoon spp. 12.1% (n = 19) and microfilariae 0.6% (n = 1). Blood parasites were found in 71.4% (5/7) of endemic bird species and 45.4% (10/22) of non-endemic species. Medium to high parasitaemia (number of parasites/number erythrocytes) was observed in birds with infections of Haemoproteus spp. and Leucocytozoon spp. Co-infections 3.8% (n = 6) were observed in two species of endemic birds. This study contributes to the knowledge of haemoparasites in endemic and non-endemic passerine birds from central Mexico highlands. Additional investigation on the molecular identification of haemosporidian parasites, pathogenicity and health status of these birds is necessary.

Heplisav-B vaccination for the prevention of hepatitis B virus infection in adults in the United States.

The prevalence of hepatitis B virus (HBV) infections is a worldwide issue that can lead to both acute and chronic complications with increased morbidity and mortality in affected individuals. Current methods of preventing HBV infections primarily include building patient immunity through administration of hepatitis B vaccinations starting at birth. Certain at-risk individuals, including those with occupational exposure to pathogenic bodily fluids, those who are sexually active or intravenous drug users, are recommended to receive some form of hepatitis B vaccination. The current standard of hepatitis B vaccination in the United States is the Engerix-B vaccine, which consists of a three-dose regimen over a 6-month time period. A new hepatitis B vaccine, Heplisav-B, has been approved for adults in the United States and requires only two doses over 1 month. The unique dosing schedule of Heplisav-B provides the potential for increasing patient compliance and therefore can aid in the effort toward protecting individuals from developing an HBV infection. Results from clinical trials showed that Heplisav-B compared favorably with Engerix-B in safety and efficacy profiles. This paper provides a review of the pharmacology, safety, clinical trials and indications for use for the Heplisav-B vaccine in the United States.

Onset of Inflammation With Ischemia: Implications for Donor Lung Preservation and Transplant Survival.

Lungs stored ahead of transplant surgery experience ischemia. Pulmonary ischemia differs from ischemia in the systemic organs in that stop of blood flow in the lung leads to loss of shear alone because the lung parenchyma does not rely on blood flow for its cellular oxygen requirements. Our earlier studies on the ischemia-induced mechanosignaling cascade showed that the pulmonary endothelium responds to stop of flow by production of reactive oxygen species (ROS). We hypothesized that ROS produced in this way led to induction of proinflammatory mediators. In this study, we used lungs or cells subjected to various periods of storage and evaluated the induction of several proinflammatory mediators. Isolated murine, porcine and human lungs in situ showed increased expression of cellular adhesion molecules; the damage-associated molecular pattern protein high-mobility group box 1 and the corresponding pattern recognition receptor, called the receptor for advanced glycation end products; and induction stabilization and translocation of hypoxia-inducible factor 1α and its downstream effector VEGFA, all of which are participants in inflammation. We concluded that signaling with lung preservation drives expression of inflammatory mediators that potentially predispose the donor lung to an inflammatory response after transplant.

Oxidative stress is a potential cost of breeding in male and female northern elephant seals.

The trade-off between current reproductive effort and survival is a key concept of life history theory. A variety of studies support the existence of this trade-off but the underlying physiological mechanisms are not well-understood. Oxidative stress has been proposed as a potential mechanism underlying the observed inverse relationship between reproductive investment and lifespan. Prolonged fasting is associated with oxidative stress including increases in the production of reactive oxygen species, oxidative damage and inflammation.Northern elephant seals (NES) undergo prolonged fasts while maintaining high metabolic rates during breeding. We investigated NES of both sexes to assess oxidative stress associated with extended breeding fasts. We measured changes in the plasma activity or concentrations of markers for oxidative stress in 30 adult male and 33 adult female northern elephant seals across their 1-3 month breeding fasts. Markers assessed included a pro-oxidant enzyme, several antioxidant enzymes, markers for oxidative damage to lipids, proteins and DNA, and markers for systemic inflammation.Plasma xanthine oxidase (XO), a pro-oxidant enzyme that increases production of oxidative radicals, and several protective antioxidant enzymes increased over breeding in both sexes. Males showed increased oxidative damage to lipids and DNA and increased systemic inflammation, while oxidative damage to proteins declined across breeding. In contrast, females showed no oxidative damage to lipids or DNA or changes in inflammation, but showed increases in oxidative damage to proteins. XO activity, antioxidant enzymes, oxidative damage markers, and inflammatory markers were strongly correlated in males but these relationships were weaker or non-existent in females.NES provide evidence for oxidative stress as a physiological cost of reproduction in a capital breeding mammal. Both sexes strongly up-regulated antioxidant defenses during breeding. Despite this response, and in contrast to similar duration non-breeding fasts in previous studies on conspecifics, there was evidence of oxidative damage to tissues. These data demonstrate the utility of using plasma markers to examine oxidative stress but also suggest the necessity of measuring a broad suite of plasma markers to assess systemic oxidative stress.

[Prognostic significance of tumor size in the survival of patients with advanced gastric carcinoma]. / Significancia pronóstica del tamaño tumoral en la sobrevida de pacientes con carcinoma gástrico avanzado.

OBJECTIVES: To determine the prognostic significance of size tumor in the survival of patients with advanced gastric carcinoma. MATERIAL AND METHODS: This retrospective study evaluated 95 patients with advanced gastric adenocarcinoma with a diameter smaller than 7 centimeters (Group I) and 85 cases with lesions equal or greater than 7 centimeters (Group II) whom underwent radical gastrectomy with lymphadenectomy D0-D1 (n=148) or D2-D3-D4 (n=32) at Belen Hospital, Trujillo, Peru, between 1966 and 1998. RESULTS: The median age of the Group I and II was of 58.1 12.9 and 58.5 15.3 years, respectively. The patients of the group II had a lower level of seric hemoglobin (p=0.007) and more frequency of lesions Borrmann type II and IV (p= 0.003). Using the log-rank test, there was no statistically significant difference with relation to five-year survival between both groups using the multivariate analysis of Cox regression. There was not statistically significance difference between the size tumoral and the survival but there were independent factors statistically related with the survival: depth of invasion (p=0.017) and lymph nodes compromised (p=0.014). CONCLUSIONS: Clinically the size of the tumor was not a factor to take as parameter in the prediction of the actuarial survival in patients with advanced gastric cancer.

Effect of pupillary dilation on corneal optical aberrations after photorefractive keratectomy.

BACKGROUND: Complaints of glare, halos, and disturbances of night vision after photorefractive keratectomy (PRK) probably result from changes in the corneal aberration structure induced by the laser ablation procedure. The purpose of this article is to characterize changes in the corneal aberration structure after PRK and to demonstrate the effect of pupil dilation on these changes. METHODS: Videokeratographs obtained preoperatively (n = 112) and at 1 (n = 94), 3 (n = 103), 6 (n = 91), 12 (n = 60), 18 (n = 53), and 24 (n = 44) months postoperatively from 112 eyes of 89 patients who had undergone PRK for myopia were analyzed. The data were used to calculate the wavefront variance of the cornea for both small (3-mm) and large (7-mm) pupils. RESULTS: For both the 3- and 7-mm pupil, coma-like aberrations increased significantly from preoperative values to 1-month postoperative values (P < .05 and P < .001, respectively); for 7-mm pupils, the postoperative values never returned to preoperative values (P < .001, 24 months). For the 3-mm pupil, spherical-like aberrations decreased significantly 1 month after surgery (P < .001), and never returned to preoperative values. For the 7-mm pupil, spherical-like aberrations increased significantly 1 month after surgery (P < .001) and did not return to preoperative values. Opening the pupil from 3 to 7 mm increased spherical-like aberrations only 7-fold before PRK. After PRK, however, pupillary dilation caused a 300-fold increase in this type of aberration. For both pupil sizes at all times after PRK, the magnitude of the surgically induced aberration correlated with the amount of the attempted correction (P < .001, r2 = 0.6 at 1 month for a 7-mm pupil). CONCLUSIONS: Photorefractive keratectomy increases the wavefront variance of the cornea; PRK changes the relative contribution of coma-like and spherical-like aberrations; after PRK, the diameter of the entrance pupil greatly affects the amount and character of the aberrations; and the magnitude of the aberration increases with the attempted correction. CLINICAL RELEVANCE: Quantitative characterization of irregular astigmatism with the measurement of aberration structures following corneal surgery and the correlation of these data with visual performance in clinical trials provide the basis for understanding patient complaints and for improving surgical approaches. Our analysis shows that, whereas induced aberrations are minimal for simulated day-time vision (3-mm pupil), the increase in aberrations measured for simulated night vision (7-mm pupil) supports the use of large treatment zones to reduce visual disturbances such as glare and halos.