From low to high latitudes: changes in fatty acid desaturation in mammalian fat tissue suggest a thermoregulatory role.

BACKGROUND: Most fatty acids (FAs) making up the adipose tissue in mammals have a dietary origin and suffer little modification when they are stored. However, we propose that some of those FAs, specifically those that can be synthesised or modified by mammals, are also being influenced by thermal forces and used as part of the mechanism to regulate core body temperature. As FA desaturation increases, adipose tissues can reach colder temperatures without solidifying. The ability to cool the superficial fat tissues helps create a thermal gradient, which contributes to body heat loss reduction. Therefore, it is expected that animals exposed to colder environments will possess adipose tissues with higher proportions of desaturated FAs. Here, through a model selection approach that accounts for phylogeny, we investigate how the variation in FA desaturation in 54 mammalian species relates to the thermal proxies: latitude, physical environment (terrestrial, semi-aquatic and fully-aquatic) and hair density. RESULTS: The interaction between the environment (terrestrial, semi- or fully-aquatic) and the latitude in which the animals lived explained best the variation of FA desaturation in mammals. Aquatic mammals had higher FA desaturation compared to terrestrial mammals. Semi-aquatic mammals had significantly higher levels of desaturated FAs when living in higher latitudes whereas terrestrial and fully-aquatic mammals did not. To account for dietary influence, a double bond index was calculated including all FAs, and revealed no correlation with latitude in any of the groups. CONCLUSIONS: We propose that FA modification is an important component of the thermoregulatory strategy, particularly in semi-aquatic mammals. Potentially this is because, like terrestrial mammals, they experience the greatest air temperature variations across latitudes, but they lack a thick fur coat and rely primarily on their blubber. Unlike fully-aquatic mammals, extremely thick blubber is not ideal for semi-aquatic mammals, as this is detrimental to their manoeuvrability on land. Therefore, the adipose tissue in semi-aquatic mammals plays a more important role in keeping warm, and the modification of FAs becomes crucial to withstand cold temperatures and maintain a pliable blubber.

In vitro fertilization with cryopreserved spermatozoa in small pieces of gonad of the scallop Argopecten purpuratus (Lamarck, 1819).

The aim of this work was to evaluate the fertilization rates through the first cleavage, obtained with fresh oocytes inseminated with sperm cryopreserved at different freezing rates (-8.8,-10 and -12 °C/min) and at two thawing rates, using cryoprotectant solution (Me2SO, at 1 M, 2 M, 3 M, 4 M and 5 M with or without egg yolk and sucrose). Sperm contained in small pieces of male gonad were frozen at the three freezing rates, stored in liquid nitrogen and later the samples were thawed at two rates by immersing the samples in water at 50 °C (rapid) or 30 °C. Control fertilization rates ranged from 69.2 ± 2.8%-45.5% ± 1.6%. To determine the best concentration of the cryoprotectant (between 1 M and 5 M), in a first step, a freezing of -15 °C/min and a rapid thawing was used. Fertilization rates ranged between 9.6 ± 2.5% and 34.6± 12.2% and the highest percentages of fertilized oocytes (34.6%) was obtained with 3 M concentration with cryoaditive. The second step, using 3 M Me2SO with cryoadditive, determined that the freezing rate -8.8 °C/min produces the best result 29 ± 2.9% of fertilized oocytes corresponding to 59.2 ± 9.1% compared to controls. Although there were no significant differences among the different freezing rates, the fertilization rate tended to be higher with a lower freezing rate. Comparing the results of the present study, which used a cryoprotective solution composed of Me2SO and a cryoadditive, to those of other studies that used Me2SO without cryoadditives, suggests that the addition of a cryoadditive to the cryoprotectant Me2SO improves the fertilizing capacity of the sperm of Argopecten purpuratus after being cryopreserved.

Diagnosis of 2009 pandemic influenza A (pH1N1) and seasonal influenza using rapid influenza antigen tests, San Antonio, Texas, April-June 2009.

Clinicians frequently use influenza rapid antigen tests for diagnostic testing. We tested nasal wash samples from 1 April to 7 June 2009 from 1538 patients using the QuickVue Influenza A+B (Quidel) rapid influenza antigen test and compared the results with real-time reverse transcription polymerase chain reaction (rRT-PCR) assay (gold standard). The prevalence of 2009 pandemic influenza A (pH1N1) was 1.98%, seasonal influenza type A .87%, and seasonal influenza type B 2.07%. The sensitivity and specificity of the rapid test for pH1N1 was 20% (95% CI, 8-39) and 99% (95% CI, 98-99), for seasonal influenza type A 15% (95% CI, 2-45) and 99% (95% CI, 98-99), and for influenza type B was 31% (95% CI, 9-61) and 99% (95% CI, 98-99.7). Rapid influenza antigen tests were of limited use at a time when the prevalence of pH1N1 and seasonal influenza in the United States was low. Clinicians should instead rely on clinical impression and laboratory diagnosis by rRT-PCR.

Training initiatives within the AFHSC-Global Emerging Infections Surveillance and Response System: support for IHR (2005).

Training is a key component of building capacity for public health surveillance and response, but has often been difficult to quantify. During fiscal 2009, the Armed Forces Health Surveillance Center, Division of Global Emerging Infections Surveillance and Response System (AFHSC-GEIS) supported 18 partner organizations in conducting 123 training initiatives in 40 countries for 3,130 U.S. military, civilian and host-country personnel. The training assisted with supporting compliance with International Health Regulations, IHR (2005). Training activities in pandemic preparedness, outbreak investigation and response, emerging infectious disease (EID) surveillance and pathogen diagnostic techniques were expanded significantly. By engaging local health and other government officials and civilian institutions, the U.S. military's role as a key stakeholder in global public health has been strengthened and has contributed to EID-related surveillance, research and capacity-building initiatives specified elsewhere in this issue. Public health and emerging infections surveillance training accomplished by AFHSC-GEIS and its Department of Defense (DoD) partners during fiscal 2009 will be tabulated and described.

Conditions influencing the appearance of thermal windows and the distribution of surface temperature in hauled-out southern elephant seals.

Pinnipeds (true seals, sea lions and walruses) inhabit two thermally different environments, air and water, so need to make continuous adjustments to maintain a balanced body temperature. The thermal isolation properties of thick blubber keep warmth within the body's core, ideal for mammals while in the water; however, when on land, this thick blubber makes it difficult to lose heat. Some pinnipeds use thermal windows, discrete patches where temperature changes on their body surface, as a mechanism to dissipate excessive heat. We identify the factors that correlate with the appearance of thermal windows and changes in body surface temperature on southern elephant seals, Mirounga leonina, while they are hauled out ashore. Infrared thermography was used to measure surface temperature of the seals. Temperature was lower on the torso than the flippers and head, suggesting that not all body sites have the same role in thermal balance. Air temperature was the main driver of variation in the surface temperature of the seals' flippers and head; seals cool their superficial tissues when the air temperature is below ~ 2°C. This minimizes heat loss by reducing the thermal gradient between their skin and the ambient air. Wind speed was the main predictor of whether thermal windows appear on a seals' body surface. When wind speed was minimal, thermal windows occurred more often, which may be associated with either hair and skin drying, or producing thermal conditions for hair and skin regrowth. The type of aggregation (huddled or alone) influenced the surface temperature of the fore flippers; however, we did not find statistical influence of the seal's sex, state of moult, or the substrate on which they were hauled out (kelp or sand). Understanding how animals maintain their thermal balance is important if we are to predict how they will respond to future climate change.

Long-term monitoring for conservation: closing the distribution gap of Arctocephalus australis in central Chile.

OBJECTIVES: Here, we present the first record of stable colonies of the South American fur seal (Arctocephalus australis), in an area where their presence has never been documented (hereafter distribution gap), as well as an update of the current distribution range of the species in central Chile. RESULTS: A national synoptic aerial census of pinnipeds was performed during the austral summer of 2019 on the Chilean coast. An additional aerial census was conducted in the same area during the austral spring of 2019 as well as a maritime census during the austral summer of 2020. The data showed the presence of South American fur seals in central Chile within their well-known distribution gap. The total abundance was registered in three colonies where fur seals were sighted: one non-breeding colony, Punta Topocalma (summer 2019: mean = 46 ± 3; spring 2019: mean = 9 ± 1); and two breeding colonies, Punta Curaumilla (summer 2019: mean = 595 ± 7; spring 2019: mean = 45 ± 4; summer 2020: mean = 744 ± 5) and Isla Santa María (summer 2019: mean = 246 ± 6). Specifically, we suggest that it is crucial to elucidate the origin of the described settled colonies, and to determine whether there has been an augment in the distribution range from either the northern population, the southern population, or both simultaneously.

Evaluating the performance of the Bayesian mixing tool MixSIAR with fatty acid data for quantitative estimation of diet.

We test the performance of the Bayesian mixing model, MixSIAR, to quantitatively predict diets of consumers based on their fatty acids (FAs). The known diets of six species, undergoing controlled-feeding experiments, were compared with dietary predictions modelled from their FAs. Test subjects included fish, birds and mammals, and represent consumers with disparate FA compositions. We show that MixSIAR with FA data accurately identifies a consumer's diet, the contribution of major prey items, when they change their diet (diet switching) and can detect an absent prey. Results were impacted if the consumer had a low-fat diet due to physiological constraints. Incorporating prior information on the potential prey species into the model improves model performance. Dietary predictions were reasonable even when using trophic modification values (calibration coefficients, CCs) derived from different prey. Models performed well when using CCs derived from consumers fed a varied diet or when using CC values averaged across diets. We demonstrate that MixSIAR with FAs is a powerful approach to correctly estimate diet, in particular if used to complement other methods.

Foraging behaviour of the South American sea lion (Otaria byronia) in two disparate ecosystems assessed through blubber fatty acid analysis.

Fatty acids have been widely used as trophic biomarkers in marine mammals. However, for the South American sea lion, the most abundant otariid in the eastern South Pacific, there is no information about blubber fatty acids and their link to diet. Here, we compare fatty acid profiles of sea lions from two distinct oceanographic regions in northern and southern Chile. Their fatty acids vary greatly between regions, suggesting dietary differences at a spatial scale. The fatty acid C22:6ω3 was more abundant in sea lions from the northern region, likely associated with consumption of anchovy, cephalopods, and crustaceans, which are rich in that fatty acid, and have been reported as their main prey items. Sea lions from the southern region were richer in C22:1 and C20:1, characteristic of teleost fish, suggesting a piscivorous diet. Males displayed a more diverse fatty acid composition than females, suggesting a wider trophic niche. Few individual sea lions within the southern region had unusually high levels of C18:2ω6, commonly found in terrestrial environments. This suggests consumption of farmed salmon, whose diet is usually based on terrestrial sources. This demonstrates how human intervention is being reflected in the tissues of a top predator in a natural environment.

Risk of dental disease non-battle injuries and severity of dental disease in deployed U.S. Army personnel.

Dental Disease and Non-Battle Injuries (D-DNBI) continue to be a problem among U.S. Army active duty (AD), U.S. Army National Guard (ARNG), and U.S. Army Reserve (USAR) deployed soldiers to Operation Iraqi Freedom/Operation New Dawn in Iraq and Operation Enduring Freedom in Afghanistan. A previous study reported the annual rates to be 136 D-DNBI per 1,000 personnel for AD, 152 for ARNG, and 184 for USAR. The objectives of this study were to describe D-DNBI incidence and to determine risk factors for dental encounters and high severity diagnoses for deployed soldiers. The 78 diagnoses were classified into three categories based on severity. Poisson regression was used to compare D-DNBI rates and logistic regression was used to analyze the risk of high severity D-DNBI. In both campaigns, Reserve had a higher risk of D-DNBI than active duty. For Afghanistan, ARNG and USAR demonstrated over 50% increased risk of D-DNBI compared to AD. In Iraq, USAR had a 17% increased risk over AD. Females had a higher risk of D-DNBI (>50%) compared to males in both campaigns. High severity D-DNBI made up 2.77% of all diagnoses. Within Afghanistan, there was a 4.6% increased risk of high severity D-DNBI for each additional deployment month.

The incidence of dental disease nonbattle injuries in deployed U.S. Army personnel.

BACKGROUND: In the past, the U.S. Army Reserve (USAR) and Army National Guard (ARNG) have exhibited lower levels of medical and dental readiness than active duty (AD) Soldiers when activated for deployment. OBJECTIVE: The objective was to compare dental disease and nonbattle injury (D-DNBI) incidence rates and describe the most common D-DNBI diagnoses in Army AD, ARNG, and USAR Soldiers deployed to Iraq (Operation Iraqi Freedom/Operation New Dawn) and Afghanistan or Kuwait (Operation Enduring Freedom). METHODS: Data from the Center for AMEDD Strategic Studies (CASS) were used to determine D-DNBI encounter rates and diagnoses for deployed Army Soldiers. RESULTS: "Dental Caries" was the leading diagnosis (10.00%) for Soldiers in both theaters. For Operation Iraqi Freedom, D-DNBI rates were highest in 2010 at 144.05 per 1,000 Soldiers per year (AD 135.77, ARNG 151.39 and USAR 183.76). In comparison, D-DNBI rates in Operation Enduring Freedom were highest in 2012 with an overall rate of 85.77 per 1,000 Soldiers per year (AD 72.48, ARNG 129.38 and USAR 129.52). CONCLUSIONS: In both campaigns, the data suggest that ARNG and USAR Soldiers had higher D-DNBI rates when compared to AD Soldiers. Further investigation is needed to decrease D-DNBI rates and to determine risk factors that may influence D-DNBI rates among Army components during deployments.

Transposición penoescrotal completa: presentación de dos casos y revisión de la literatura / Complete penoscrotal transposition: A two case report and literature review

La transposición penoescrotal es una anomalía congénita donde el escroto se localiza en posición superior y anterior al pene. Se puede clasificar según su compromiso en transposición completa o incompleta, siendo más frecuente esta última. Se han reportado alrededor de 27 casos en la literatura de transposición penoescrotal completa y la gran mayoría se ha asociado con otras malformaciones congénitas. Presentamos dos casos de óbitos fetales con transposición penoescrotal completa con malformaciones congénitas, y además realizamos una revisión de la literatura de los casos publicados.

Penoscrotal transposition is a congenital anomaly in which the scrotum is positioned superiorly and anteriorly to the penis. It may be classified as complete or incomplete transposition, according to severity. Incomplete type is more common. Around 27 cases of complete penoscrotal transposition have been reported in the literature usually associated with other congenital malformations. We report on two cases on fetal obitus with complete penoscrotal transposition associated with congenital malformations. We also reviewed the literature on published cases.

Effectiveness of seasonal influenza vaccines against influenza-associated illnesses among US military personnel in 2010-11: a case-control approach.

INTRODUCTION: Following the 2009 influenza A/H1N1 (pH1N1) pandemic, both seasonal and pH1N1 viruses circulated in the US during the 2010-2011 influenza season; influenza vaccine effectiveness (VE) may vary between live attenuated (LAIV) and trivalent inactivated (TIV) vaccines as well as by virus subtype. MATERIALS AND METHODS: Vaccine type and virus subtype-specific VE were determined for US military active component personnel for the period of September 1, 2010 through April 30, 2011. Laboratory-confirmed influenza-related medical encounters were compared to matched individuals with a non-respiratory illness (healthy controls), and unmatched individuals who experienced a non-influenza respiratory illness (test-negative controls). Odds ratios (OR) and VE estimates were calculated overall, by vaccine type and influenza subtype. RESULTS: A total of 603 influenza cases were identified. Overall VE was relatively low and similar regardless of whether healthy controls (VE = 26%, 95% CI: -1 to 45) or test-negative controls (VE = 29%, 95% CI: -6 to 53) were used as comparison groups. Using test-negative controls, vaccine type-specific VE was found to be higher for TIV (53%, 95% CI: 25 to 71) than for LAIV (VE = -13%, 95% CI: -77 to 27). Influenza subtype-specific analyses revealed moderate protection against A/H3 (VE = 58%, 95% CI: 21 to 78), but not against A/H1 (VE = -38%, 95% CI: -211 to 39) or B (VE = 34%, 95% CI: -122 to 80). CONCLUSION: Overall, a low level of protection against clinically-apparent, laboratory-confirmed, influenza was found for the 2010-11 seasonal influenza vaccines. TIV immunization was associated with higher protection than LAIV, however, no protection against A/H1 was noted, despite inclusion of a pandemic influenza strain as a vaccine component for two consecutive years. Vaccine virus mismatch or lower immunogenicity may have contributed to these findings and deserve further examination in controlled studies. Continued assessment of VE in military personnel is essential in order to better inform vaccination policy decisions.

Ginecomastia (Estudio retrospectivo sobre 54 casos operados) / Gynecomastia: retrospective study of 54 cases surgically treated

Se realiza un estudio retrospectivo de 54 casos operados en el Hospital de Endocrinología y Metabolismo Dr. Arturo Oñativia de Salta. Entre los años 1987 y 2001 fueron intervenidas 63 ginecomastias que representan el 5,58 por ciento de los diagnósticos anátomo-patológicos y el 7,18 por ciento de los informes benignos. Sobre 54 pacientes con historias clínicas presentes se detallan aspectos epidemiológicos, formas de presentación, estudios practicados, diagnóstico causal, características anátomo-patológicas y se intenta cursar una guía para el estudio de la ginecomastia como así también para el tratamiento médico y quirúrgico. Por último se realiza determinación de receptores hormonales por inmunomarcación en 19 casos observando pisitividad nuclear epitelial para estrógenos en el 68,42 por ciento y de progesterona en el 47,36 por ciento.

Intubación endotraqueal retrógrada / Retrograde endotracheal intubation

Objetivo. Promover el empleo de la técnica de intubación endotraqueal retrógrada guiada en intubaciones difíciles por variantes anatómicas y patológicas agregadas. Se estudiaron 20 pacientes adultos programados para cirugía electiva y de urgencia. Del grupo estudiado los estados físicos ASA fueron: 1 (1 paciente 5 porciento),2 (10 pacientes 50 porciento),3(8 pacientes 40 porciento)y 4(1 paciente 5 porciento). El tipo de cirugía involucrada fue: columna cervical, cirugía maxilofacial, cirugía reconstructiva, neurocirugía y cirugía torácica. Las variantes anatómicas y las patologías agregadas más frecuentemente encontradas fueron: fracturas cervicales, fracturas del arco cigomático y abcesos gigantes maxilares con apertura limitada de boca, artritis reumatoide deformante, traumatismos cráneo-faciales y cicatrices retráctiles de cara y cuello. La técnica de intubación endotraqueal retrógrada guiada puede considerarse como una opción útil en pacientes con laringoscopía e intubación dificíl donde el laringoscopio de fibra óptica aunque deseable no es indispensable cuando ocurren problemas no anticipados de la vía aérea. La técnica permite además evitar la realización de traqueostomías innecesarias. Concluimos que aún siendo la naturaleza invasiva de la técnica debe de tomarse en cuenta como un recurso adicional para resolver problemas de intubación dificíl.