2,419 research outputs found
Plasma ACTH, α-MSH and cortisol variations in the dog during the oestrous cycle in different photoperiods
The hypothalamic-pituitary-adrenal axis (HPA) is a complex system regulated by multiple factors.Sexual dimorphism of this axis has been described in different species under physiological conditions and it hasbeen proposed that sexual hormones could have an effect on it. There are only a few reports about sex-linkedvariations in HPA axis hormones in the dog. Thus, studying the impact of sexual hormones on the HPA axis wouldbroaden the knowledge about its function in this species. Therefore, the objective of this study was to determinewhether there are variations in HPA plasma hormones (ACTH, alfa-melanocyte-stimulating hormone [α-MSH]and cortisol) according to the sex and photoperiod (positive or negative photoperiod were considered when theduration of the light hours of the day was more than 12 or less than 12, respectively) under basal conditions (likeanoestrus) and throughout the oestrous cycle in the female dog. The population under study consisted of 11 intactfemale and 14 intact male dogs. Under basal conditions neither ACTH nor α-MSH concentrations showed differencesbetween sexes and different photoperiods. Cortisol showed greater values in the negative photoperiod thanin the positive, both in females and males (P = 0.03 and P = 0.015, respectively). Throughout the oestrous cycle,all the studied hormones showed variations (P < 0.0001). The greatest concentrations of ACTH were observed atproestrus, while α-MSH and cortisol showed their greatest concentrations at oestrus. The three hormones decreasedin diestrus. ACTH and cortisol concentrations were higher in the negative photoperiod (P = 0.04 and P < 0.0001,respectively), while α-MSH concentrations were higher in the positive photoperiod (P = 0.012). In the group offemales oestradiol and progesterone correlated with ACTH (r = 0.75, P < 0.0001; r = 0.34, P < 0.01, respectively),α-MSH (r = 0.49, P < 0.0001; r = 0.52, P < 0.0001, respectively) and cortisol (r = 0.33, P < 0.01; r = 0.5, P < 0.0001,respectively). These results show that in females, HPA axis hormones vary during the oestrous cycle in relation tooestradiol and progesterone fluctuations. The ACTH, α-MSH and cortisol concentrations also showed differencesbetween photoperiods in females, but only cortisol did so in males. These findings suggest that sexual hormonescould have an effect on the HPA axis. Further research needs to be done to fully understand this interaction andthe mechanisms involved.Fil: Gallelli, María Florencia. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Monachesi, N.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Miceli, Diego Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Cabrera Battler, M. F.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Gomez, N. V.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Meikle, A.. Universidad de Montevideo; UruguayFil: Castillo, V, A.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; Argentin
Ectopic ACTH syndrome in a dog with a mesenteric neuroendocrine tumour: a case report
Ectopic ACTH secretion is provoked by extra-pituitary tumours that secrete ACTH, constituting an infrequent type of Cushing Syndrome in the dog. Neuroendocrine tumours (NET) are characterised by the synthesis of peptides with hormone activity. A dog with clinical diagnosis of Cushing?s syndrome and presenting an abdominal tumour located in the area of the left adrenal gland was sent to the hospital. Cortisol was not inhibited at four and eight hours after the application of low-dose dexamethasone and the cortisol/creatinine ratio was elevated (93 × 10-6, reference values < 10 × 10?6). Plasma ACTH measurements were high (28.6 pmol/l, reference values 5.5?14.3 pmol/l). On computed tomography, the tumour was found in the meso-epigastrium, with both adrenal glands hyperplasic and no alteration of the pituitary image. The tumour was located between the two layers of the meso-colon and was removed using laparoscopy. After surgery, ACTH concentrations became normal and clinical signs remitted. The histopathological diagnosis was NET, with positive ACTH immunostaining.Fil: Castillo, V. A.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Pessina, P. P.. Universidad de la Republica; UruguayFil: García, J. D.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Hall, P.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Galleli, M. F.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Miceli, Diego Daniel. Universidad de Buenos Aires. Facultad de Cs.veterinarias. Departamento de Medicina. Clinica Medica de Animales Peque?os; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental (i); ArgentinaFil: Cabrera Blatter, M. F.. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; Argentin
Knowledge and Impact of COVID-19 on Middle-Aged and Older People Living with HIV in Lima, Peru
COVID-19 has had an unprecedented worldwide impact, and Peru has had one of the highest COVID-19 case rates despite implementation of an early strict nationwide quarantine. Repercussions on Peru's healthcare system may impact vulnerable populations, particularly people with HIV (PWH). We explored knowledge of COVID-19 and the socioeconomic and health impact of the pandemic among middle-aged and older PWH. A cross-sectional telephone survey was administered to 156 PWH age ≥40 years receiving care in one of two large HIV clinics in Lima, Peru. The majority of PWH (age 52 ± 7.7 years, 41% female, 65% completed secondary school or less) were knowledgeable regarding COVID-19 symptoms and prevention methods. Nearly half of those employed prior to the pandemic reported job loss. Female sex (unadjusted prevalence ratio [PR] 1.85 [95%CI 1.27-2.69]), low educational level (PR 1.62 [1.06-2.48]) and informal work (PR 1.58 [1.06-2.36]) were risk factors for unemployment but not in adjusted models. Increased anxiety was reported in 64% and stress in 77%. COVID-19 has had a substantial socioeconomic and mental health impact on PWH living in Lima, Peru, particularly those with lower educational levels and informal workers. Efforts are needed to ensure continued medical care and socioeconomic support of PWH in Peru
Modelling the potential distribution of the genus Polylepis occurring in Colombia with conservation considerations
En Colombia, el género Polylepis está representado por P. quadrijuga, P. sericea y P. incana. La modelización de la distribución geográfica potencial permite identificar áreas relevantes para conservar especies focales. Los objetivos de este trabajo fueron establecer las áreas de distribución potencial de las tres especies e identificar oportunidades de conservación en áreas protegidas a escala nacional, regional y local. Para esto, se recopilaron 223 registros biológicos (GBIF y SIB Colombia) que, junto con 23 variables ambientales, fueron los insumos para modelizar la distribución potencial en MaxEnt 3.3.3K. Como oportunidades de conservación, se cuantificó la presencia de reservas del SINAP-Colombia en las áreas de distribución potencial de las especies. Las variables que más contribuyen en los modelos son altitud, temperatura estacional y rango de temperatura media mensual, entre otras. P. sericea presentó el área de distribución potencial más amplia, con 23243.5 km² en las tres cordilleras; le siguieron P. quadrijuga, con 6264.2 km² en la Cordillera Oriental y P. incana, con 1772.8 km² en la Cordillera Central y la frontera con Ecuador. Una parte de dichas distribuciones potenciales se encuentra en, al menos, un tipo de área protegida. P. incana tiene 59.5% del área de distribución potencial dentro de alguna figura de protección, P. quadrijuga presenta 44.8% de área potencial de distribución ubicada dentro de cualquier figura de protección y P. sericea, al tener una mayor superficie potencial a partir de la modelización, posee un porcentaje más bajo de representatividad (33.7%) en áreas protegidas del SINAP. Finalmente, a partir del análisis de amenazas y oportunidades se proponen áreas clave para la conservación de Polylepis y zonas para la búsqueda de posibles poblaciones no reportadas.The genus Polylepis in Colombia is represented by P. quadrijuga, P. sericea and P. incana. The modeling of the potential geographic distribution allows identifying areas of importance for the conservation of focal species. The objectives of this work were to establish the potential distribution areas of the three species and identify conservation opportunities in protected areas at national, regional and local levels. For this, 223 biological records were compiled (mainly from GBIF and SIB Colombia), which, together with 23 environmental variables, were the inputs for the modeling of the potential distribution in MaxEnt 3.3.3K. As conservation opportunities, the presence of reserves of SINAP-Colombia in the areas of potential distribution of the species was quantified. The variables that contribute most in the models are altitude, seasonal temperature and monthly average temperature range, among others. P. sericea showed the largest potential distribution area, with 23243.5 km² in the three mountain ranges, followed by P. quadrijuga, with 6264.2 km² in the Eastern Cordillera, and P. incana, with 1772.8 km² in the Central Mountain Range and the border with Ecuador. A part of said potential distributions are found in, at least, one type of protected area. P. incana has 59.5% of the potential distribution area within some protection figure, followed by P. quadrijuga, with 44.8% potential distribution area located within any protection figure, and P. sericea, which, having a larger area potential result of the modeling, showed a lower percentage (33.7%) of representativeness in protected areas of SINAP. Finally, from the analysis of threats and opportunities, key areas for the conservation of Polylepis and zones for the search of possible non-reported populations are proposed
Ni(2,2′:6′,2′′-terpyridine) 2: a high-spin octahedral formal Ni(0) complex †
We have synthesised and characterised the complex Ni(tpy)2 (tpy = 2,2′:6′,2′′-terpyridine). This formally Ni(0) complex is paramagnetic both in the solid state and in solution (S = 2). The crystal structure shows an octahedral geometry, with molecules arranged in independent dimers involving π-stacking between pairs of complexes. Magnetic measurementes and DFT calculations suggest the existence of temperature-dependent intermolecular antiferromagnetic coupling in the solid state
Adrenal cortex stimulation with hCG in spayed female dogs with Cushing’s syndrome: Is the LH-dependent variant possible?
Background: The expression and overexpression of luteinizing hormone (LH) receptors in the canine adrenal gland cortex have been reported. Therefore, it was hypothesized that a LH-dependent form of Cushing’s syndrome (CS) could exist in dogs.Aim: To assess whether the adrenal gland post-ovariectomy (OVx) exhibits a greater response to adrenocorticotrophin (ACTH) stimulation; to evaluate whether the adrenal gland responds to human chorionic gonadotropin (hCG) stimulation by increasing the release of cortisol; and to consider whether hCG stimulus testing would be useful as a diagnosis for possible cases of LH-dependent CS.Methods: Cortisol concentrations were measured from healthy female dogs (n=16) at baseline and following ACTH stimulation before and 2 months after gonadectomy (OVx). Cortisol concentrations were also measured for female dogs with CS (n = 14) following administration of hCG (5000 IU). A post-hCG cortisol concentration greater than 140 nmol/l was used to define dogs with LH-dependent Cushing’s syndrome.Results: In normal female dogs, both pre- and post-stimulation cortisol concentrations increased following OVx (p = 0.002 and p = 0.0003, respectively). In female dogs with CS, cortisol concentrations increased following stimulation with hCG in 57% (8/14; p = 0.002). Age at the time of OVx was associated (p = 0.015) with the cortisol response to hCG [8 (5–9) years vs. 3.5 (2–6) years, p = 0.0013).Conclusion: Based on these results, an LH-dependent form of CS occurs in spayed female dogs, and that it is more likely to occur when female dogs are spayed later in life
Knowledge-based: facilitating access to medicines in Latin America
The World Health Organization (WHO), with the scientific support of the International Pharmaceutical Federation (FIP), guides the development of multisource pharmaceutical products for market authorization using in vivo bioequivalence studies or, where applicable, in vitro biowaiver strategies based on the Biopharmaceutical Classification System (BCS). A review of the regulatory framework guiding generic medicines approval in Latin American countries revealed that less than 50% of regional health authorities offer a generic medicines development pathway utilizing a BCS-based biowaiver strategy. Aligned with the ONE FIP Strategy to facilitate access to medicines, a regional case study was carried out to implement and harmonize BCS-based biowaiver knowledge in Latin American countries. A steering committee involving regional representatives from health authorities, the pharmaceutical industry, and universities were established to coordinate to develop activities. A series of digital engagement events were held in Spanish and English with representatives from Latin America to share knowledge on BCS-based regulatory strategy, promote collaborations, and explore the alignment of biowaiver approval and regulatory pathways among Latin American countries. Feedback from diverse Latin American stakeholders demonstrated inconsistent implementation of bioequivalence testing within the region. However, there is support for a synergistic approach among countries to reduce duplication and increase efficiency in market authorization for generic medicines. This includes alignment with the WHO Prequalification of Medicines program as well as the development of a computational database for the classification of active pharmaceutical ingredients to demonstrate therapeutic interchangeability of immediate-release oral dosage forms according to the BCS. FIP-facilitated digital learning opportunities raised awareness of the BCS-based biowaiver regulatory strategy among Latin American stakeholders. It resulted in a plan to continually strengthen collaborative efforts in the region to harmonize regulations relevant to drug development generics medicines to introduce cost-effective medicines products that benefit public health
Cistoadenoma seroso "gigante" de ovario en una adolescente. Serum giant ovarian cystoadenoma in an adolescent
Se presenta el caso de una adolescente de 16 años de edad con antecedentes de haber sido operada a los 5 años por Persistencia del Conducto Arterioso, que ingresa en el Hospital Pediátrico Provincial Docente "Pepe Portilla" de Pinar del Río, Cuba, por dolor torácico irradiado al brazo derecho y aumento de volumen del abdomen, por lo que se indicó ultrasonido abdominal detectándose gran masa quística abdominal. Es trasladada al Servicio de Cirugía Pediátrica, donde se completa su estudio y se realiza intervención quirúrgica, encontrándose un quiste gigante de ovario derecho que pesó 9 kilogramos, corroborándose el diagnóstico histológico de Cistoadenoma Seroso de Ovario (Quiste Seroso Simple). La paciente evolucionó satisfactoriamente. Los autores presentan las experiencias derivadas de la atención del caso, y revisan la literatura médica sobre el tema con especial referencia al diagnóstico y tratamiento. Palabras clave: Edema Masivo de Ovario, Quiste de Ovario. ABSTRACT A 16-year-old case of an adolescent is presented, having undergone a surgical procedure at 5 years old because of an arterious duct patency, being admitted at "Pepe Portilla" Provincial Teaching Pediatric Hospital in Pinar del Río, Cuba, presenting chest pain with radiation to the right arm and increase of the abdominal volume and an abdominal ultrasound was prescribed and it was detected a great abdominal cystic mass. She was transferred to the Pediatric Surgical Service, and the study is completed, and she undergoes a surgical procedure, finding a 9-kilogram giant right ovarian cyst which was proved in the histological diagnosis to be a Serum Ovarian Cystoadenoma (Simple Serum Cyst) The patient had a succesful recovery. The authors present the experiences attained and review the medical literature on this case, making emphasis on its diagnosis and treatment. Key words: MASS OVARIAN EDEMA, OVARIAN CYST
Ecology and conservation of polylepis forests: What do we know and what do we ignore?
Los bosques de Polylepis, endémicos de las montañas de Sudamérica, suelen estar asociados con sitios relativamente inaccesibles como quebradas, roquedales o laderas empinadas. Las hipótesis más discutidas que explican esta asociación son: 1) factores abióticos como la humedad, la temperatura o el viento, ó 2) factores antropogénicos como la protección del ramoneo por ganado doméstico, la tala o los fuegos iniciados por el ser humano. Para resumir el estado de avance en el conocimiento, realizamos una revisión cuantitativa sobre los estudios de ecología y conservación de bosques de Polylepis a lo largo de toda su distribución. Identificamos 139 publicaciones relevantes, de las que el 36% estuvo concentrado en la Argentina. Las publicaciones incluyen 20 de las ~27 especies existentes, de las cuales las más estudiadas son P. australis y P. tarapacana, con 45 y 21 publicaciones, respectivamente. En el otro extremo, hay 7 especies no representadas en publicaciones. Las disciplinas más populares fueron la ecología de poblaciones (35%) y los estudios sobre biodiversidad y comunidades (18%). Muy pocos estudios se repiten de una región a la otra. Los estudios que intentan comprender la contribución relativa de factores abióticos vs. antropogénicos para explicar la asociación de los bosques con lugares relativamente inaccesibles señalan una contribución mayor de los factores antrópicos, aunque todos están concentrados en el extremo sur de la distribución de Polylepis en la Argentina. Sugerimos áreas de vacancia en estudios y posibles mejoras en la producción de nuevas publicaciones y en la red de interacciones entre investigadores interesados en los ecosistemas de Polylepis.Polylepis forests, endemic to the Andes of South America, are generally associated to relatively inaccessible sites such as ravines, rocky or steep slopes. The reasons for this association have been widely debated and could be of abiotic origin such as humidity, temperature or winds, or due to anthropogenic origin such as protection from browsing by domestic cattle, felling or human ignited fires. We performed a quantitative review on the ecology and conservation of Polylepis forests with the objective of summarizing the state of the art in this topic. We identified 139 relevant publications; 36% were concentrated in Argentina. The publications include 20 of the ~27 existing species; the most studied were P. australis and P. tarapacana, with 45 and 21 publications, respectively. In the opposite extreme, there were 7 species without publications. The most popular disciplines were population ecology (35%) and studies on biodiversity and communities (18%). Very few studies of the same type were repeated from one region to the other. The studies that attempt to quantify the relative contribution of abiotic and anthropogenic factors in restricting forest to inaccessible sites show a stronger contribution of human impact, but are all concentrated in the south of distribution of Polylepis forest in Argentina. We suggest research vacancy areas and possible improvements in the production of new publications and in the network of interactions between researchers interested in Polylepis ecosystems.Fil: Renison, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; ArgentinaFil: Morales, Laura. University of California at Davis; Estados UnidosFil: Cuyckens, Griet An Erica. Universidad Nacional de Jujuy. Facultad de Ciencias Agrarias. Centro de Estudios Ambientales Territoriales y Sociales; Argentina. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Ecorregiones Andinas; ArgentinaFil: Sevillano, Cristian Steven. Cornell University; Estados UnidosFil: Cabrera Amaya, Diego M.. Jardín Botánico de Bogotá José Celestino Mutis; Colombi
Multidimensional Machine Learning Model to Calculate a COVID-19 Vulnerability Index
In Colombia, the first case of COVID-19 was confirmed on 6 March 2020. On 13 March 2023, Colombia registered 6,360,780 confirmed positive cases of COVID-19, representing 12.18% of the total population. The National Administrative Department of Statistics (DANE) in Colombia published in 2020 a COVID-19 vulnerability index, which estimates the vulnerability (per city block) of being infected with COVID-19. Unfortunately, DANE did not consider multiple factors that could increase the risk of COVID-19 (in addition to demographic and health), such as environmental and mobility data (found in the related literature). The proposed multidimensional index considers variables of different types (unemployment rate, gross domestic product, citizens’ mobility, vaccination data, and climatological and spatial information) in which the incidence of COVID-19 is calculated and compared with the incidence of the COVID-19 vulnerability index provided by DANE. The collection, data preparation, modeling, and evaluation phases of the Cross-Industry Standard Process for Data Mining methodology (CRISP-DM) were considered for constructing the index. The multidimensional index was evaluated using multiple machine learning models to calculate the incidence of COVID-19 cases in the main cities of Colombia. The results showed that the best-performing model to predict the incidence of COVID-19 in Colombia is the Extra Trees Regressor algorithm, obtaining an R-squared of 0.829. This work is the first step toward a multidimensional analysis of COVID-19 risk factors, which has the potential to support decision making in public health programs. The results are also relevant for calculating vulnerability indexes for other viral diseases, such as dengue
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