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101.
102.
Ancient connections between animals and human are seen in cultures throughout the world in multiple forms of interaction with the local fauna that form the core of Ethnozoology. Historically, ethnozoological publications grew out of studies undertaken in academic areas such as zoology, human ecology, sociology and anthropology - reflecting the interdisciplinary character of this discipline. The rich fauna and cultural diversity found in Brazil, with many different species of animals being used for an extremely wide diversity of purposes by Amerindian societies (as well as the descendents of the original European colonists and African slaves), presents an excellent backdrop for examining the relationships that exist between humans and other animals. This work presents a historical view of ethnozoological research in Brazil and examines its evolution, tendencies, and future perspectives. In summary, literature researches indicated that ethnozoology experienced significant advances in recent years in Brazil, although from a qualitative point of view improvement is still needed in terms of methodological procedures, taxonomic precision, and the use of quantitative techniques. A wide range of methodologies and theories are available in different areas of learning that can be put to good use in ethnozoological approaches if the right questions are asked. The challenges to studying ethnozoology in Brazil are not insignificant, and the tendencies described in the present study may aid in defining research strategies that will maintain the quantitative growth observed in the recent years but likewise foster needed qualitative improvements. 相似文献
103.
Angélica MS Firmo Mônica MP Tognella Saulo R Silva Raynner RRD Barboza Rômulo RN Alves 《Journal of ethnobiology and ethnomedicine》2012,8(1):1-12
Background
Blue Land Crab (Cardisoma guanhumi) is one of the most important crustacean species captured and commercialized in Brazil. Although this species is not considered to be threatened with extinction, populations of C. guanhumi are known to be rapidly diminishing due to heavy harvesting pressures and degradation of their natural habitats, highlighting the necessity of developing and implanting management and protection strategies for their populations. There have been no ethnozoological publications that have focused specifically on C. guanhumi, in spite of importance of this type of information for developing efficient management plans of resource utilization. So, the present work describes the ethnoecological aspects of the capture and commercialization of C. guanhumi by a fishing community in northeastern Brazil.Methods
Field work was carried out in the municipality of Mucuri, Bahia in Brazil, between the months of January and March/2011 through the use of open semi-structured interviews with all of the crustacean harvesters in city who acknowledged their work in capturing this species, totaling 12 interviewees. The informants were identified through the use of the "snowball" sampling technique. In addition to the interviews themselves, the "guided tour" technique and direct observations was employed.Results
According all the interviewees, the C. guanhumi is popularly called "guaiamum" and is collected in "apicum" zones. They recognize sexual dimorphism in the species based on three morphological characteristics and the harvesters also pointed two stages in the reproductive cycle during the year and another phase mentioned by the interviewees was ecdysis. All of the interviewed affirmed that the size and the quantities C. guanhumi stocks in Mucuri have been diminishing. All of the interviewees agreed that the species and other mangrove resources constituted their principal source of income. The harvesters dedicated three to five days a week to collect Blue Land Crabs and the principal technique utilized for capturing is a trap called a "ratoeira" (rat-trap).Conclusions
The results of the present work demonstrated that the community retains a vast and important volume of knowledge about C. guanhumi that could subsidize both scientific studies and the elaboration of viable management and conservation strategies for this species. 相似文献104.
Background
Women with diabetes are sometimes advised to express breast milk antenatally to prepare for breastfeeding and to store colostrum for infant feeding in preventing or treating hypoglycaemia after the birth. The acceptability, risks and benefits of this practice have not been evaluated. This was aimed to investigate the pattern of antenatal breast expression uptake and its relationship with birth outcomes in women with diabetes.Methods
This was part of a two year retrospective cohort study of pregnant women with diabetes (type 1, 2 and gestational diabetes) who gave birth during 2001–2003 in Derby Hospitals NHS Foundation Trust (n = 94). The information on the practice of antenatal breastfeeding expression and birth outcomes was collected via self-administered questionnaires and by examining maternity records.Results
Thirty-seven percent of women (35/94) recalled that they were advised to express antenatally and 17% did (16/94). The mean gestational age at birth for women who hand-expressed was lower than that for those who did not (mean difference (MD) (95% confidence intervals (CI)): -1.2 (?2.4 to 0.04), p = 0.06). A higher proportion of babies from the antenatal expression group were admitted to special care baby units (SCBU) (MD (95% CI): 21% (?3.9 to 46.3).Conclusions
Less than half the women who stated that they were advised to express, did so. There seems to be an indication that antenatal breast milk expression and lower gestational age at birth are associated. The trend of a higher rate of SCBU admission for babies from the breast milk expression group compared to those who did not express antenatally is of concern. An appropriately-powered randomised controlled trial is needed to determine the safety of this practice and its acceptability to women and health professionals before it can be recommended for implementation in practice.105.
I Meral M Esrefoglu KA Dar S Ustunova MS Aydin M Demirtas 《Biotechnic & histochemistry》2016,91(8):493-500
We investigated the effects of Nigella sativa on apoptosis and gamma-aminobutyric acid (GABAA) receptor density in cerebral cortical and hippocampal neurons in a pentylenetetrazol (PTZ)-induced kindling model in rats. The PTZ kindling model was produced by injecting PTZ in subconvulsive doses to rats on days 1, 3, 5, 8, 10, 12, 15, 17, 19, 22 and 24 of the study into animals of PTZ treated (PTZ) and PTZ + N. sativa treated (PTZ + NS) groups. Clonic and tonic seizures were induced by injecting a convulsive dose of PTZ on day 26 of the study. Rats in the PTZ + NS group were treated also with a 10 mg/kg methanolic extract of N. sativa 2 h before each PTZ injection. Rats in the control group were treated with 4 ml/kg saline. The number of neurons that expressed GABAA receptors in the hippocampus and cerebral cortex of rats in the PTZ and PTZ + NS groups increased significantly. There was no significant difference in the number of GABAA receptors between the PTZ and PTZ + NS groups. GABAA receptor density of the neurons in the cerebral cortex, but not hippocampus, was increased in PTZ group compared to controls. We observed a significant increase in the number of apoptotic neurons in the cerebral cortex of rats of both the PTZ and PTZ + NS groups compared to controls. We observed a significant decrease in the number of the apoptotic neurons in the cerebral cortex of rats in the PTZ + NS group compared to the PTZ group. N. sativa treatment ameliorated the PTZ induced neurodegeneration in the cerebral cortex as reflected by neuronal apoptosis and neuronal GABAA receptor frequency. 相似文献
106.
Tania de Waal Danica Liebenberg Gert J Venter Charlotte MS Mienie Huib van Hamburg 《Journal of vector ecology》2016,41(1):179-185
African horse sickness (AHS) is an infectious, non‐contagious arthropod‐borne disease of equids, caused by the African horse sickness virus (AHSV), an orbivirus of the Reoviridae family. It is endemic in sub‐Saharan Africa and thought to be the most lethal viral disease of horses. This study focused on detection of AHSV in Culicoides imicola (Diptera: Ceratopogonidae) pools by the application of a RT‐qPCR. Midges were fed on AHSV‐infected blood. A single blood‐engorged female was allocated to pools of unfed nulliparous female midges. Pool sizes varied from 1 to 200. RNA was extracted and prepared for RT‐qPCR. The virus was successfully detected and the optimal pool size for the limit of detection of the virus was determined at a range between 1 to 25. Results from this investigation highlight the need for a standardized protocol for AHSV investigation in Culicoides midges especially for comparison among different studies and for the determination of infection rate. 相似文献
107.
Production of the virus‐like particles of nipah virus matrix protein in Pichia pastoris as diagnostic reagents
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Narcisse MS Joseph Kok Lian Ho Beng Ti Tey Chon Seng Tan Norazizah Shafee Wen Siang Tan 《Biotechnology progress》2016,32(4):1038-1045
The matrix (M) protein of Nipah virus (NiV) is a peripheral protein that plays a vital role in the envelopment of nucleocapsid protein and acts as a bridge between the viral surface and the nucleocapsid proteins. The M protein is also proven to play an important role in production of virus‐like particles (VLPs) and is essential for assembly and budding of NiV particles. The recombinant M protein produced in Escherichia coli assembled into VLPs in the absence of the viral surface proteins. However, the E. coli produced VLPs are smaller than the native virus particles. Therefore, the aims of this study were to produce NiV M protein in Pichia pastoris, to examine the structure of the VLPs formed, and to assess the potential of the VLPs as a diagnostic reagent. The M protein was successfully expressed in P. pastoris and was detected with anti‐myc antibody using Western blotting. The VLPs formed by the recombinant M protein were purified with sucrose density gradient ultracentrifugation, high‐performance liquid chromatography (HPLC), and Immobilized Metal Affinity Chromatography (IMAC). Immunogold staining and transmission electron microscopy confirmed that the M protein assembled into VLPs as large as 200 nm. ELISA revealed that the NiV M protein produced in P. pastoris reacted strongly with positive NiV sera demonstrating its potential as a diagnostic reagent. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1038–1045, 2016 相似文献
108.
Equine arteritis virus (EAV) induces apoptosis in infected cells. Cell death caused by EAV has been studied mainly using three cell lines, BHK-21, RK-13 and Vero cells. The mechanism of apoptosis varies among cell lines and results cannot be correlated owing to differences in EAV strains used. We evaluated different markers for apoptosis in BHK-21, RK-13 and Vero cell lines using the Bucyrus EAV reference strain. Acridine orange/ethidium bromide staining revealed morphological changes in infected cells, while flow cytometry indicated the extent of apoptosis. We also observed DNA fragmentation, but the DNA ladder was detected at different times post-infection depending on the cell line, i.e., 48, 72 and 96 h post-infection in RK-13, Vero and BHK-21 cells, respectively. Measurement of viral titers obtained with each cell line indicated that apoptosis causes interference with viral replication and therefore decreased viral titers. As an unequivocal marker of apoptosis, we measured the expression of caspase-3 and caspases-8 and -9 as extrinsic and intrinsic markers of apoptosis pathways, respectively. Caspase-8 in BHK-21 cells was the only protease that was not detected at any of the times assayed. We found that Bucyrus EAV strain exhibited a distinctive apoptosis pathway depending on the cell line. 相似文献
109.
Anna Marina Liberati Verena De Angelis Marco Fizzotti Monica Schippa Michela Cecchini Daniela Adiuto Francesco Di Clemente Lucia Palmisano Elisabetta Micozzi Massimo Zuccaccia Saverio Cinieri 《Cancer immunology, immunotherapy : CII》1994,38(5):323-331
The association of low doses of interleukin-2 (IL-2; 5 IU/ml) and interferon (IFN; 10 IU/ml) induced an additive or synergic stimulatory effect on natural killer (NK) activity (32%) in peripheral blood samples from hairy-cell leukemia patients, both those with active disease and those in remission. The synergic NK stimulatory effect was more commonly found in samples from patients with active disease, while the additive effect was more frequent in the patients in remission. The IL-2/IFN combination provoked a nonadditive nonsynergic NK-stimulatory effect in a further 19.8% samples. The targets of the IL-2/IFN combination were typical NK cells, as shown by the fact that there was increased cytotoxicity (synergic, additive or nonadditive nonsynergic) against the K562, but not the Daudi cell line in peripheral blood mononuclear cell samples treated with the combination of the two cytokines. When CD16+/CD56+ or CD57+/CD16+/CD56+ cells were removed, the NK-stimulatory effect was lost. The fact that the NK-cell-enhancing activity of the IL-2/IFN combination was reduced when Percoll fractions 2 and 3 were used, but still persisted in 66% of tests, may have been due to cytotoxicity being higher in the untreated fractions 2 and 3 than in the untreated unfractionated samples. One of the factors responsible for the NK-stimulatory effect appears to be the capacity of the IL-2/IFN combination to trigger an increase in IFN synthesis. If similar experiments give like results in samples from patients suffering from other B-cell lymphoproliferative, or HIV-associated disorders, all of which are characterized by a deficiency in NK activity, it should be possible to use low-dose IL-2/IFN to treat these disorders and, perhaps, residual neoplastic disease without exposing the patient to undue toxicity. Further, by testing other combinations one should be able to identify the lowest IL-2 and IFN doses that would effectively boost the additive or synergic effect in a greater number of cases. 相似文献
110.
Age variations in the relation of body mass indices to estimates of body fat and muscle mass 总被引:1,自引:0,他引:1
In some chronic disease studies, distinctions have been made regarding the importance of body mass index (BMI) as a risk factor in younger versus older men and women. In order to determine the significance of these differences in BMI-disease associations, we determined the extent of age-dependent variations in the relation of BMIs to body composition in large probability samples of U.S. men and women from the First and Second U.S. National Health and Nutrition Examination Surveys (NHANES I and II). BMIs are more highly correlated with estimates of body fat in younger than in older men and women, and with muscle mass in older than in younger adults. Caution should be exercised in interpreting the significance of BMI as a risk factor for chronic disease, particularly in comparison of age groups. 相似文献