. Tel/Fax: +55 11 30917690 RESUMO. A Leptospirose é uma doença infecciosa de caráter sistêmico, sua ocorrência é evidenciada em regiões de clima tropical e subtropical, sendo prevalente nas Américas, onde ocorre de forma endêmica na América Latina e Caribe. No Brasil, a doença tem caráter endêmico, sendo comuns surtos epidêmicos na época das chuvas. A Leptospirose também é considerada uma doença de risco ocupacional, atingindo trabalhadores agrícolas (arrozais e canaviais), mineradores, coletores de lixo e encarregados da limpeza pública, trabalhadores das redes de água e esgotos, além de médicos veterinários e tratadores de animais. Assim, este trabalho propõe uma revisão sistemática acerca da literatura científica sobre os fatores associados à leptospirose. A metodologia baseou-se no rastreamento de publicações disponíveis no SCiELO, MEDLINE e LILACS. O controle da leptospirose animal deve assentar-se na integração de medidas profiláticas instituídas simultaneamente nos três níveis da cadeia de transmissão: fontes de infecção (vertebrados infectados), vias de transmissão (água, solo e fômites contaminados), susceptíveis vertebrados não infectados e não imunizados e proteção ao mesmo, a qual é obtida com o uso de vacinas inativadas que contenham sorovares de leptospiras.Palavras chaves: bactéria, patogenia, laboratorial, animais susceptíveis Leptospirosis: Review ABSTRACT. Leptospirosis is an infectious systemic disease; its occurrence is evidenced in tropical and subtropical regions. It is prevalent in the Americas, occurring endemically in Latin America and Caribbean. In the Brazil, the disease is endemic; outbreaks are common during the rainy season. Leptospirosis is also considered an occupational risk of disease, affecting agricultural workers (rice paddies and sugarcane), miners, garbage and cleaning charge of public collectors, workers of water and sewage, as well as veterinarians and keepers of animals. In this way, this study proposes a systematic review of the scientific publication on the factors associated with leptospirosis. The method logy screened available studies in SciELO, MEDLINE, and LILACS. The control of animal leptospirosis should be based on the integration of prophylactic measures imposed simultaneously on all three levels of the chain of transmission: infection source (infected vertebrates), transmission routes (water, soil and contaminated fomites), likely vertebrates uninfected and not immunized and protection to it, which is achieved with the use of inactivated vaccines containing the serotypes of Leptospira.Keywords: Bacteria, patogenie, laboratory, animals IntroduçãoA leptospirose é uma doença ou infecção naturalmente transmissível entre os animais vertebrados e o homem (Côrtes, 1993; Colemen, 2000), de curso agudo a crônico que afeta diversas espécies de animais domésticos e silvestres, além do homem, assumindo considerável importância como problema econômico e de saúde pública (Faine et al., 1999).
al for both, the establishment of appropriate management systems, and for the use of new species as animal models. In this study, we used light and electron microscopy to characterize the sexual development stages of the guinea pig (Cavia porcellus) in specimens of 30, 45 and 90 days of age. We observed the differentiation of spermatocytes only through transmission electron microscopy in the leptotene, zygotene and pachytene phases of meiosis, in 30-day-old animals. During puberty, there was differentiation of the germinative epithelium and formation of the acrosome. Spermatozoa, however, were not detected. Thus, we could infer that puberty happens after 45 days of age. Sexual maturity was evident in 90-day-old specimens. Our results showed that changes in the testicular germinative epithelium during the postnatal sexual development in guinea pig led to morphological changes, including the ones related to the development of Leydig and Sertoli cells, which are directly related to puberty. In this work, we provide new morphological subsidies for a better understanding of reproductive parameters of this species, enabling its use as an animal model in the field of the reproductive biology.
The effects of protein energy deprivation (PED) on trigeminal ganglion sectional area, neuronal density, number of neurons/section, neuronal body area and neuronal nucleus area were evaluated. The protein deprivation prenatally and for 21 days postnatally leads to reduce body weights (40% of control weights) and an increase in the number of neurons/section (35% more than control). Most neuron perikarya were within 400-600 m 2 (53,7%) in protein-deprived animals and 600-900 m 2 (48,2%) in the control group. Rows of neuronal bodies were separated by bundles of nerve and collagen fibers in both groups. Ganglionic neurons from both groups contained cytoplasmic Nissl's corpuscles and spherical nuclei with eccentric and large nucleoli. The elongated nuclei of the fibrocytes revealed the main axis oriented parallel to the bundles nerve fibers. By scanning electron microscopy, the structure of the ganglion from both groups was found to be similar.
The germinative, Sertoli and Leydig cells of two caviomorph rodents (Cavia porcellus and Dasyprocta agouti) were counted as well as the estimation of the total volume of the testis and the total volume of seminiferous tubules and interstitium in prepubertal, pubertal and adult animals. The number of spermatogonia, spermatocytes and spermatids cells increased during the pubertal phase in both rodents, notably the spermatid cells. The spermatocyte and spermatid slightly decreased in the adult of both rodents, but the increment in spermatogonia cells number was seen, mainly in cutias. The number of Sertoli cells increased in pubertal rodents, but in the adult the number reduced. Substantial number of Leydig cells was counted in pubertal and adult guinea pigs. In cutias, the number of Leydig cells increased in pubertal phase and decline in adults. The design-based stereological method has proven to be unbiased and reliable to be applied in reproduction studies.
The study reported the influence of the high and acute dose of Letrozole on the testis morphology in paca (Cuniculus paca), an aromatase inhibitor that reduces the endogenous estrogen, the essential hormone for spermatogenesis. Morphological changes were observed in seminiferous epithelium with germ cells with apoptotic characteristics and presence of vacuoles and nuclei in pycnose.
IntroductionThe elevated costs with biologic products threaten the sustainability of health services, and, therefore, the access to these medicines in the perspectives of user, health professional, health manager and system. The entry of biosimilar products in the market could be an option to subsidize the search for solutions to those problems.MethodsWe conducted a rapid review using the databases Medline (via PubMed), EMBASE, Cochrane Library and CRD. The eligibility criteria were HTAs, systematic reviews and cross-sectional studies.ResultsLiterature search retrieved 640 registries and, after duplicate removal, screening of titles and abstracts and full text reading, nine cross-sectional studies were selected. From a user's point of view, the following barriers were identified: lack of knowledge about the medicine, distance between the place of living and the health service (especially in the rural area), long waiting periods for service, passivity in regard to treatment. From a health professional's point of view the barriers were: acceptability of the expert in regard to treatment, interchangeability and substitution, the perception of lack of data showing efficacy and safety. Finally, from the payer's (or health manager) point of view, the barriers were: high cost of medicine, problems with reimbursement and bureaucracy. We did not retrieve any barriers from the health system's perspective from the selected studies.ConclusionsThe entry of biosimilar medicines in the market can induce competition and, therefore, reduce prices of biologic treatments. It is necessary to search for potential solutions to the access barriers identified in this rapid review.
A dogma of mammalian reproduction states that primordial germ cells in females are restricted to the intrauterine phase and only small portions of oocytes are available for ovulation during the adult life. Among the rare exceptions to this rule is the plains viscacha. It polyovulates up to 800 oocytes per cycle, from which 10 to 12 are implanted, but only 1 to 2 conceptuses survive. To better understand the main mechanisms involved in these patterns of super-ovulation, super-implantation, and embryonic loss in the viscacha, we conducted an analysis of the ovary and uterus of pregnant females and their conceptuses. Pregnant females (n = 16) of ~50 and 90 days of gestation (early to mid-gestation) were selected for conceptus recovery. Hemi-ovariohysterectomy was performed following surgical and anaesthetic protocols used for laboratory animals and the conceptuses collected. Female fetuses of Day 50 (n = 2) and 90 (n = 1) of gestation were obtained from Estación de Cría de Animales Silvestres, Buenos Aires, Argentina. The reproductive organs were investigated by means of gross morphology, histology (hematoxilin and eosin), stereology (quantification of the volume of the ovary and number of ovary follicles), immunohistochemistry (PCNA, Oct-4, VEGF, and Caspase-3), and transmission electron microscopy. In the Day 50 fetal samples, the ovaries had an ovoid shape with smooth surface without apparent folds. First steps of subdivision were observed in the ovary of fetus of 90 days. The total volume of all fetal ovaries was of 4.8 mm2 and a coefficient of variation (CV) of 0.32. The ovaries of adult individuals had remarkable invaginations with surface projections and were small, asymmetrical, and dorsoventrally flattened with a mean of 77.6 mm3 (CV = 0.47). Only adult females had differentiation of germ cells. Primordial follicles had a mean of 9.9 × 105 (CV = 0.19), representing 93% of the total number of ovarian follicles. The mean of primary follicles was 3.05 × 104 (CV = 0.36), whereas for secondary follicles it was 2.75 × 104 (CV = 0.50), each representing 3% of all ovarian follicles. The number of antral follicles in several stages of development was 8.64 × 103 (CV = 0.75), representing 1% of the follicles. Primordial follicles expressed pluripotency (Oct-4+) and proliferation (PCNA+) markers, as well as the primary follicles. The cells did not react for Caspase-3 as marker for apoptosis. Variations regarding to the vascularization of the different regions of the uterine horn were observed, which were more intense and efficient near to the cervix. Data showed that a specialised, highly convoluted structure of the ovarian cortex developed in the intrauterine phase as a prerequisite for massive super-ovulation, associated with the inhibition of apoptosis and continued proliferation of germ cells, as well as maintenance of several corpora lutea during the adult life. Thus, a highly complex pattern of polyovulation, polyimplantation, and controlling mechanisms has evolved in the female reproductive system of the viscacha that mainly was associated with the maternal side. After an in-depth analysis of the arterial and venous vascularization of the uterine horns and uteri, we speculate that specializations regarding the vasculature and musculature evolved first and then contributed as a compensatory or controlling mechanism for polyovulation and polyimplantation. In conclusion, polyovulation in the viscacha represents a unique enigma in reproductive biology.
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