RESUMO
In August 2021, two juvenile male Antarctic fur seals (Arctocephalus gazella) stranded in the southeastern Brazilian coast and were referred to rehabilitation centers. The animals presented increased body temperature, prostration, respiratory distress and despite treatment died. A necropsy following a standardized protocol was performed, and formalin-fixed tissues were processed for microscopic examination. Samples were screened for morbillivirus, herpesvirus, and Brucella spp. by molecular analyses (PCR, RT-PCR). Bacteriological culture was performed in samples collected from the lungs, trachea, and lymph nodes of both cases. The main histopathologic findings were of infectious nature, including multifocal necrotizing and fibrinous mixed interstitial pneumonia, bronchiolitis, and bronchitis, with intralesional myriad bacteria associated with vascular fibrinoid necrosis. Pseudomonas aeruginosa was isolated from tracheal and lung swabs of Case 1, and Klebsiella oxytoca was found in nostril swabs, tracheobronchial lymph nodes, and lung of Case 2. Gammaherpesvirus infection was detected in both cases, and the sequences retrieved were classified into the genus Percavirus. All tested samples were PCR-negative for Brucella spp. and morbillivirus. We hypothesize that the deficient immunological status in association with starvation predisposed the reactivation of herpesvirus and secondary bacterial co-infections. To the authors' knowledge, this is the first molecular detection of herpesvirus in an Antarctic pinniped. These findings reinforce that Otariid gammaherpesvirus circulating in the Southern Hemisphere are likely endemic in the Arctocephalus genus. This report contributes to the current knowledge of health aspects affecting wild pinnipeds, especially in the poorly studied Antarctic species.
Assuntos
Otárias , Infecções por Herpesviridae , Animais , Brasil , Otárias/virologia , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Masculino , Sepse/veterinária , Sepse/microbiologia , Sepse/virologiaRESUMO
Caffeine is the psychostimulant most consumed worldwide but concerns arise about the growing intake of caffeine-containing drinks by adolescents since the effects of caffeine on cognitive functions and neurochemical aspects of late brain maturation during adolescence are poorly known. We now studied the behavioral impact in adolescent male rats of regular caffeine intake at low (0.1mg/mL), moderate (0.3mg/mL) and moderate/high (1.0mg/mL) doses only during their active period (from 7:00 P.M. to 7:00 A.M.). All tested doses of caffeine were devoid of effects on locomotor activity, but triggered anxiogenic effects. Caffeine (0.3 and 1mg/mL) improved the performance in the object recognition task, but the higher dose of caffeine (1.0mg/mL) decreased the habituation to an open-field arena, suggesting impaired non-associative memory. All tested doses of caffeine decreased the density of glial fibrillary acidic protein and synaptosomal-associated protein-25, but failed to modify neuron-specific nuclear protein immunoreactivity in the hippocampus and cerebral cortex. Caffeine (0.3-1mg/mL) increased the density of brain-derived neurotrophic factor (BDNF) and proBDNF density as well as adenosine A1 receptor density in the hippocampus, whereas the higher dose of caffeine (1mg/mL) increased the density of proBDNF and BDNF and decreased A1 receptor density in the cerebral cortex. These findings document an impact of caffeine consumption in adolescent rats with a dual impact on anxiety and recognition memory, associated with changes in BDNF levels and decreases of astrocytic and nerve terminal markers without overt neuronal damage in hippocampal and cortical regions.
Assuntos
Ansiedade/induzido quimicamente , Encéfalo/efeitos dos fármacos , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Memória/efeitos dos fármacos , Reconhecimento Psicológico/efeitos dos fármacos , Animais , Ansiedade/fisiopatologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/fisiologia , Relação Dose-Resposta a Droga , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/crescimento & desenvolvimento , Hipocampo/fisiologia , Masculino , Memória/fisiologia , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Wistar , Receptor A1 de Adenosina/metabolismo , Reconhecimento Psicológico/fisiologia , Proteína 25 Associada a Sinaptossoma/metabolismoRESUMO
Research has shown that genetic polymorphisms in biotransformation enzymes, such as CYP1A1 and GSTM1, are related to a greater or lesser susceptibility to various cancers. We made an analysis of CYP1A1m1 SNP and GSTM1 null genotypes in a family group (71 members) related by consanguinity who had an unusually high incidence of cancer and a high frequency of smokers. There were no significant differences in genotype frequencies in this family when compared to data for Brazilian populations. Possibly, the high incidence of cancer in this sample is associated with smoking and/or other factors not detected in this survey.
Assuntos
Citocromo P-450 CYP1A1/genética , Glutationa Transferase/genética , Neoplasias/genética , Polimorfismo de Nucleotídeo Único/genética , Brasil , Feminino , Predisposição Genética para Doença/genética , Humanos , Masculino , LinhagemRESUMO
Male patients with an extra sex chromosome or autosome are expected to present primary hypogonadism at puberty owing to meiotic germ-cell failure. Scarce information is available on trisomy 21, a frequent autosomal aneuploidy. Our objective was to assess whether trisomy 21 presents with pubertal-onset, germ-cell specific, primary hypogonadism in males, or whether the hypogonadism is established earlier and affects other testicular cell populations. We assessed the functional status of the pituitary-testicular axis, especially Sertoli cell function, in 117 boys with trisomy 21 (ages: 2months-20year). To compare with an adequate control population, we established reference levels for serum anti-Müllerian hormone (AMH) in 421 normal males, from birth to adulthood, using a recently developed ultrasensitive assay. In trisomy 21, AMH was lower than normal, indicating Sertoli cell dysfunction, from early infancy, independently of the existence of cryptorchidism. The overall prevalence rate of AMH below the 3rd percentile was 64.3% in infants with trisomy 21. Follicle-stimulating hormone was elevated in patients <6months and after pubertal onset. Testosterone was within the normal range, but luteinizing hormone was elevated in most patients <6months and after pubertal onset, indicating a mild Leydig cell dysfunction. We conclude that in trisomy 21, primary hypogonadism involves a combined dysfunction of Sertoli and Leydig cells, which can be observed independently of cryptorchidism soon after birth, thus prompting the search for new hypotheses to explain the pathophysiology of gonadal dysfunction in autosomal trisomy.
Assuntos
Hormônio Antimülleriano/sangue , Síndrome de Down/fisiopatologia , Hipogonadismo/fisiopatologia , Adolescente , Adulto , Criança , Pré-Escolar , Síndrome de Down/complicações , Hormônio Foliculoestimulante/sangue , Humanos , Hipogonadismo/sangue , Hipogonadismo/etiologia , Lactente , Recém-Nascido , Células Intersticiais do Testículo/fisiologia , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão , Células de Sertoli/fisiologia , Testículo/anatomia & histologia , Testosterona/sangueRESUMO
CONTEXT: Recently, new methodologies have been applied to commercial immunofluorometric (IFMA) and immunochemiluminometric (ICMA) LH and FSH assays. OBJECTIVE: The objective of the study was to use ICMA to establish basal and GnRH-stimulated LH and FSH reference values in normal subjects of different ages and sexual development, compared with IFMA. DESIGN AND METHODS: We established basal and GnRH-stimulated LH and FSH levels of 315 prepubertal and pubertal children (170 males and 145 females) divided into five groups according to Tanner stage. Of these, 106 subjects (59 males and 47 females) were submitted to GnRH test. The prepubertal upper limit of normal for basal LH, determined by the 95th percentiles of the prepubertal population, were 0.2 IU/liter (ICMA) and 0.6 IU/liter (IFMA) in both genders. RESULTS: No overlap of basal LH levels determined by ICMA was observed between prepubertal and pubertal males, but basal LH determined by IFMA overlapped in 11.8% of subjects. In girls, both methods yielded overlapping values (10.4%, ICMA; and 84.6%, IFMA). The LH peak after GnRH stimulation that defined puberty was 4.1 IU/liter (ICMA) and 3.3 IU/liter (IFMA) in boys and 3.3 IU/liter (ICMA) and 4.2 IU/liter (IFMA) in girls. After GnRH stimulation, values determined by the two methods overlapped in both genders. CONCLUSIONS: We conclude that ICMA is more sensitive and precise than IFMA, permitting differentiation of pubertal and prepubertal stage in boys under basal conditions. However, in girls the overlap of basal values was marked, indicating the need for the GnRH test to establish maturity of the hypothalamus-pituitary-gonadal axis.
Assuntos
Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/sangue , Adolescente , Criança , Pré-Escolar , Feminino , Imunofluorescência , Humanos , Lactente , Luminescência , Masculino , Valores de Referência , Caracteres SexuaisRESUMO
To establish normative data and determine the value of fluorometric AutoDELFIA assays (Wallac Oy) in the investigation of precocious puberty, we determined serum levels of LH, FSH, testosterone, and estradiol under basal and GnRH-stimulated conditions in 277 normal subjects at various pubertal stages and in 77 patients with precocious puberty. A substantial overlap was observed in basal and GnRH-stimulated gonadotropin levels in normal individuals of both sexes with pubertal Tanner stages 1 and 2. The 95th percentile of the normal prepubertal population was the cut-off limit between prepubertal and pubertal levels. These limits were 0.6 IU/L in both sexes for basal LH, 9.6 IU/L in boys and 6.9 IU/L in girls for peak LH after GnRH stimulation, 19 ng/dL in boys for basal testosterone, and 13.6 pg/mL in girls for basal estradiol. Basal and peak LH exceeding these limits were considered positive tests for the diagnosis of gonadotropin-dependent precocious puberty. According to these criteria, the sensitivities of basal and peak LH for the latter diagnosis were 71.4% and 100% in boys, and 62.7% and 92.2% in girls. The specificity and positive predicted value were 100% in both sexes for basal and peak LH levels. The negative predicted values for basal and peak LH were 62.5% and 100% in boys, and 40.6% and 76.5% in girls. Basal and GnRH-stimulated FSH levels overlapped among the various pubertal stages in normal subjects and were, in general, not helpful in the differential diagnosis of precocious puberty. In conclusion, basal LH levels were sufficient to establish the diagnosis of gonadotropin-dependent precocious puberty in 71.4% of boys and 62.7% of girls. In the remaining patients, a GnRH stimulation test was still necessary to confirm this diagnosis. Finally, suppressed LH and FSH levels after GnRH stimulation indicate gonadotropin-independent sexual steroid production.
Assuntos
Fluorometria/normas , Puberdade Precoce/diagnóstico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Hormônio Liberador de Gonadotropina , Gonadotropinas/sangue , Humanos , Masculino , Puberdade Precoce/sangue , Valores de Referência , Esteroides/sangueRESUMO
OBJECTIVES: Although calcitonin (Ct) deficiency has been described in chronic autoimmune thyroiditis (CAT) it is unclear at what stage in the disease it develops. We have analysed the Ct secretory responses of patients in two different evolutionary stages of CAT, namely the goitrous and atrophic phases. DESIGN: We studied the Ct response to combined calcium (2 mg/kg) and pentagastrin (0.5 microgram/kg) intravenous infusion in 27 patients with CAT and 30 normal adult controls. The cases were divided into two groups. The first comprised eleven women with CAT and goitrous subclinical hypothyroidism (GH), aged 28.6 +/- 10.1 years--at diagnosis they had increased thyroid autoantibody titres and cytological features compatible with stages 1 and 2 of Hashimoto's thyroiditis. The second comprised 16 females with CAT and an atrophic thyroid confirmed by ultrasound scan, aged 38.0 +/- 9.2 years--these patients were severely hypothyroid at diagnosis and were termed AH (atrophic hypothyroidism). Both groups (GH and AH) received replacement doses of thyroxine sufficient to restore euthyroidism for at least six months before the stimulation tests. Control group (C) consisted of 20 healthy women (A), aged 30.0 +/- 9.6 years, and 10 healthy men (B), aged 34.7 +/- 8.0 years. Serum Ct was measured by IRMA. The Ct secretory response was related to thyroid size and cytological data, when available. RESULTS: Basal Ct concentrations in groups GH (0.08 ng/l, median) and AH (0.07 ng/l, median) were significantly lower than those of female controls (0.58 ng/l, median). Stimulated Ct peak values in groups GH (0.08 ng/l, median) and AH (0.19 ng/l, median) were significantly lower than those of female controls (13.61 ng/l, median). Also, both basal (2.72 ng/l, median) and stimulated Ct levels (35.73 ng/l, median) in male controls were significantly higher than in female controls given already. A positive correlation between the Ct secretory reserve and thyroid dimensions, evaluated by ultrasound scan, was found only in patients with thyroid atrophy (AH; rs = 0.61, P < 0.05). CONCLUSIONS: We have found low basal and stimulated calcitonin values in patients with chronic autoimmune thyroiditis and thyroid enlargement, which represents an early phase of chronic autoimmune thyroiditis. Our data have also confirmed previous findings of deficient calcitonin secretion in advanced stages of chronic autoimmune thyroiditis in which thyroid atrophy is usually found. These findings may be associated with C-cell destruction following progressive, nonspecific follicular cell damage caused by lymphocytic infiltration and fibrosis of the gland.
Assuntos
Calcitonina/deficiência , Tireoidite Autoimune/metabolismo , Adulto , Análise de Variância , Calcitonina/sangue , Cálcio/sangue , Estudos de Casos e Controles , Doença Crônica , Feminino , Bócio/metabolismo , Bócio/patologia , Humanos , Hipotireoidismo/metabolismo , Hipotireoidismo/patologia , Masculino , Pentagastrina , Estimulação Química , Testes de Função Tireóidea , Glândula Tireoide/patologia , Tireoidite Autoimune/patologiaRESUMO
The objective of the present investigation was to study quantitatively C cells in Hashimoto's thyroiditis (HT) by analyzing 22 thyroids obtained at autopsy or thyroidectomy from 16 patients with thyroiditis and from 6 normal subjects. Six different areas were sampled on average and labeled with a monoclonal anticalcitonin antibody by immunohistochemistry using the avidin-biotin-peroxidase complex. Normal thyroids from adult patients with no thyroid disease were used as control. C cells were counted in 1 cm2 fields and the mean number of cells per field was calculated. Data were analyzed statistically by the Mann-Whitney test. The inflammatory process detected in cases of HT was usually moderate (50%) and the number of C cells ranged from 0 to 12.2 per 1 cm2 field. The number of C cells in normal thyroids ranged from 20 to 148 per 1 cm2 field, with a median of 35.2 cells per field. The results demonstrate a significant decrease in C cell number in HT compared with normal thyroids, indicating that the inflammatory process causes destruction of both follicular and C cells, which are replaced by fibrosis.
Assuntos
Glândula Tireoide/patologia , Glândula Tireoide/fisiopatologia , Tireoidite Autoimune/patologia , Tireoidite Autoimune/fisiopatologia , Calcitonina/metabolismo , Contagem de Células , Humanos , Imuno-HistoquímicaRESUMO
The potential usefulness of determining serum testosterone (T) fractions in women, ie, sex hormone-binding globulin (SHBG)-bound T, albumin-bound T (Alb-T), and free T (FT) fractions, was explored in a variety of clinical situations. Serum T, SHBG, and albumin concentrations were measured by standardized methods and using binding constants of T to SHBG and albumin, we calculated serum T fractions, which agreed remarkably with measured values of SHBG-T and nonbound T. Serum T levels did not change in normal women examined during the follicular and luteal phases of the menstrual cycle, but SHBG levels were elevated in the luteal phase, changing the distribution of T, with increased SHBG-T and less T distributed to other fractions. Women taking oral contraceptives had decreased serum T levels, but use of androgen-like oral contraceptives decreased SHBG levels and T distribution to this binding protein, whereas use of non-androgen-like oral contraceptives increased SHBG levels, resulting in the expected shift of T fractions. Women receiving phenytoin for seizure disorders and women with Graves' disease exhibited increased SHBG levels with concomitant increased SHBG-T and decreased distribution of T to nonbound fractions. Women with hirsutism exhibited decreased SHBG levels irrespective of total serum T levels, and the T/SHBG ratio was elevated in this population. However, of interest were women with morbid obesity (nonhirsute) who had similar low levels of SHBG and T/SHBG ratios that were indistinguishable from those of hirsute women.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Caracteres Sexuais , Testosterona/sangue , Adolescente , Adulto , Androgênios/farmacologia , Disponibilidade Biológica , Anticoncepcionais Orais/classificação , Anticoncepcionais Orais/farmacologia , Feminino , Doença de Graves/sangue , Hirsutismo/sangue , Humanos , Masculino , Ciclo Menstrual/sangue , Obesidade Mórbida/sangue , Fenitoína/uso terapêutico , Valores de Referência , Convulsões/sangue , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/química , Testosterona/farmacocinéticaRESUMO
Os autores analisam as caracteristicas clinicas e laboratoriais, com especial enfase a citologia por biopsia aspirativa com agulha fina, em 50 pacientes portadores de tiroidite cronica. A incidencia de tiroidite cronica foi maior no sexo feminino e no grupo de bocio difuso. A cintilografia mostrou hipocaptacao difusa em 52,63% dos casos, bem como os anticorpos positivos em mais de 47%. Com base nos resultados citologicos, afirmam ser a tiroidite cronica a causa mais frequente de hipotiroidismo (50,40%), sendo a do tipo Hashimoto a de maior prevalencia. Sugerem a importancia da citologia no diagnostico diferencial de tiroidite cronica e neoplasias malignas. Enfatizam, finalmente, a biopsia aspirativa com agulha fina tecnica de facil execucao e a citologia, metodo seguro e adicional para o estudo das tiroidites, contribuindo substancialmente para deteccao e diagnostico de tiroidite cronica em seu estadio precoce