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21.
Endoscopically and ultrasonographically guided ovum pick up were studied in 15 heifers once per week. Althogether 60 sessions were carried out. The number of aspirated follicles per animal (13.0 vs 10.3) did not differ significantly between both methods. Similar recovery rates (39 % vs 44 %) were achieved after repeated sessions. As a consequence the number of recovered oocytes per animal (5.2 vs 4.7) were not significantly different. Inter-animal- and intra-animal-variations were more important for the results than the applied methods. In contrast to these findings the quality of recovered cumulus-oocyte-complexes (COC) was significantly influenced by the methods. The COC were divided into 4 categories a) oocytes with compact cumulus, b) oocytes with rest of compacted cumulus, c) oocytes with expanded cumulus and d) oocytes without cumulus. There was a higher denudation rate of COC when using the endoscopic aspiration (62.0 % vs 6.6 %) because of turbulent current in this aspiration system. Advantages and disadvantages of both methods are described and discussed. Generally, the ultra sonographic method is the less traumatic procedure for the vagina, fornix and for abdominal organs. The other method is less traumatic for the ovaries.  相似文献   
22.
Mycetoma is a neglected tropical chronic granulomatous inflammatory disease of the skin and subcutaneous tissues. More than 70 species with a broad taxonomic diversity have been implicated as agents of mycetoma. Understanding the full range of causative organisms and their antibiotic sensitivity profiles are essential for the appropriate treatment of infections. The present study focuses on the analysis of full genome sequences and antibiotic inhibitory concentration profiles of actinomycetoma strains from patients seen at the Mycetoma Research Centre in Sudan with a view to developing rapid diagnostic tests. Seventeen pathogenic isolates obtained by surgical biopsies were sequenced using MinION and Illumina methods, and their antibiotic inhibitory concentration profiles determined. The results highlight an unexpected diversity of actinomycetoma causing pathogens, including three Streptomyces isolates assigned to species not previously associated with human actinomycetoma and one new Streptomyces species. Thus, current approaches for clinical and histopathological classification of mycetoma may need to be updated. The standard treatment for actinomycetoma is a combination of sulfamethoxazole/trimethoprim and amoxicillin/clavulanic acid. Most tested isolates had a high IC (inhibitory concentration) to sulfamethoxazole/trimethoprim or to amoxicillin alone. However, the addition of the β-lactamase inhibitor clavulanic acid to amoxicillin increased susceptibility, particularly for Streptomyces somaliensis and Streptomyces sudanensis. Actinomadura madurae isolates appear to have a particularly high IC under laboratory conditions, suggesting that alternative agents, such as amikacin, could be considered for more effective treatment. The results obtained will inform future diagnostic methods for the identification of actinomycetoma and treatment.  相似文献   
23.
Endocrine disruptors (EDs) represent a major toxicological and public health issue, and the xenoestrogen bisphenol A (BPA) has received much attention due to its high production volume and widespread human exposure. Also, due to its similarity to diethylstilbestrol, a known human carcinogen, BPA has been investigated for its genotoxic and carcinogenic properties, but the results have been either inconclusive or controversial. Metabolically activated BPA has previously been shown to form DNA adducts both in vitro and in rat liver. The present study was designed (a) to assess the sensitivity threshold of DNA-adduct detection by 32P-postlabelling in an acellular system and (b) to evaluate the formation of DNA adducts in both liver and mammary cells of female CD-1 mice receiving BPA in their drinking water (200 mg/kg body weight) for eight consecutive days. The reaction of BPA with calf thymus DNA, in the presence of S9 mix, resulted in a dose-dependent formation of multiple DNA adducts, with a detection limit of 10 ng of this ED under our experimental conditions. Administration of BPA to mice confirmed that DNA adducts are formed in liver (3.4-fold higher levels than in controls). In addition, new evidence is provided that DNA adducts are formed in target mammary cells (4.7-fold higher than in controls). Although DNA adducts do not necessarily evolve into tumours or other chronic degenerative diseases, the formation of these molecular lesions in target mammary cells may bear relevance for the potential involvement of BPA in breast carcinogenesis.  相似文献   
24.
Little information is available on methods of sperm capacitation for IVF in the horse. In this study, we summarized results of several independent trials that compared acrosome reaction, hyperactivation and chromatin integrity of fresh or cryopreserved stallion spermatozoa after treatment with heparin or with calcium ionophore. We also examined the influence of spermatozoa storage (fresh vs. cryopreserved), capacitation treatment, oocyte maturation time and cumulus morphology on the penetration rate and fertilization rate. We recovered cumulus-oocyte-complexes (COCs) from ovaries by ultrasound guided follicle aspiration or by scraping of follicles from ovaries obtained at a slaughterhouse. Upon recovery, we evaluated the cumulus morphology, and the COCs were matured in vitro for 18 to 24 or 26 to 40 h. Fresh semen and cryopreserved semen were treated either with heparin (200 microg/mL) or calcium ionophore (7.14 microM). Overall, 28.4% (99/349) of the oocytes were penetrated, and 12.9% (45/349) were fertilized. Fresh spermatozoa treated with calcium ionophore showed a higher penetration rate than cryopreserved spermatozoa (36.0 vs. 0%). Fresh and heparin-treated spermatozoa showed a penetration rate of 29.1%, and the same treatment for cryopreserved spermatozoa showed a penetration rate of 33.7%; none of these differences was significant (P>0.05). Fertilization rates after the calcium and heparin treatment followed the same trend and also showed no significant differences. Prolonged maturation period resulted in higher penetration (P<0.05) and fertilization rates in compact (26 to 40 h: 37.7 and 13.1% vs. 18 to 24 h: 13.1 and 2.8%) and in tendency in expanded COCs (26 to 40 h: 40.0 and 30.3% vs. 18 to 24 h: 29.4 and 13.5%). In oocytes with only a few cumulus cells, the rates tended to be higher after the shorter incubation (18 to 24 h: 33.5 and 18.8% vs. 26 to 40 h: 17.2 and 6.5%). We observed hyperactivation more frequently in fresh than in cryopreserved semen after different treatments (43.2, 39.1 and 35.4% for heparin, calcium ionophore and control vs. 15.7, 10.8 and 5.7%, respectively). We observed significant changes in the acrosome reaction of fresh spermatozoa after heparin treatment (62.6 vs. 48.2%, P<0.05), as well as in cryopreserved spermatozoa after calcium ionophore treatment (31.7 vs. 17.6%, P<0.05). The chromatin integrity was significantly reduced after heparin treatment of fresh spermatozoa, in comparison to control and calcium ionophore (81.0 vs. 87.3 and 86.6, P<0.02). We also observed a similar reduction of chromatin quality after heparin treatment in cryopreserved spermatozoa, but the difference was significant only between heparin and calcium ionophore treatment [77.4 vs. 86.4 (P<0.02) and 84.9]. The results in the this retrospective study show that capacitating fresh spermatozoa with calcium ionophore, or using heparin in cryopreserved spermatozoa, results in higher penetration and fertilization rates of in vitro matured horse oocytes. A prolonged maturation time of 26 to 40 h is necessary for compact cumulus oocyte complexes to achieve the fertilization capacity. Further investigation is needed to show the developmental capacity of these fertilized oocytes.  相似文献   
25.
The aim of the present investigation was to study the effect of oocyte selection on the efficiency of bovine nuclear transfer in terms of increased blastocyst production. For this purpose, prior to in vitro maturation (IVM), oocytes were selected for their developmental competence on the basis of glucose-6-phosphate dehydrogenase (G6PDH) activity indicated by brilliant cresyl blue (BCB) staining. It has been hypothesized that growing oocytes have a higher level of active G6PDH in comparison to the mature oocytes. Compact cumulus oocyte complexes (COCs) were recovered from slaughterhouse-collected bovine ovaries and classified either as control group, which were placed immediately into culture without exposure to BCB stain, or treatment group, which were stained with BCB for 90min before culture. Treated oocytes were then divided into BCB- (colourless cytoplasm, increased G6PDH) and BCB+ (coloured cytoplasm, low G6PDH) based on their ability to metabolize the stain. After IVM, oocytes were subjected to nuclear transfer procedure for the production of cloned embryos which were then cultured for a period of 8 days to determine the blastocyst rate. The BCB+ oocytes yielded a significantly higher blastocyst rate (39%) than the control (21%) or BCB- oocytes (4%). These results show that the staining of bovine cumulus-oocyte complexes with BCB before in vitro maturation could be used to select developmentally competent oocytes for nuclear transfer. In addition, G6PDH activity could prove to be a useful marker for determining the oocyte quality in future.  相似文献   
26.
27.
The aim of the present study was to examine the cumulus morphology and the oocyte chromatin quality of camel cumulus-oocyte complexes (COCs) at the time of recovery, and to monitor changes in oocyte chromatin configuration and apoptosis in cumulus cells from camel COCs during in vitro maturation (IVM) (0, 12, 24, 32, 36, 42, and 48 p.IVM) depending on pregnancy of donors. A total of 1023 COCs were isolated from sliced ovaries after slaughtering of 47 pregnant and 43 non-pregnant camels in an abattoir. The mean number of COCs per donor was 10.3 in pregnant and 12.5 in non-pregnant donors. The cumulus morphology of COCs was independent of the type of donor and was divided in COCs with compact (26.9 and 28%), dispersed (39.3 and 46%), corona radiata cumulus investment (27.9 and 21.7%) and without cumulus (6 and 4.2%), respectively for pregnant and non-pregnant donors. The highest proportion of COCs exhibited dispersed cumulus (P<0.05). Oocytes with meiotic stages of diplotene >50% were found only in compact (55 and 56.5%) and in dispersed COCs (58.4 and 60%), respectively for pregnant and non-pregnant donors. During IVM (0-48h) the first significant onset of specific meiotic stages were different in oocytes from pregnant donors: metaphase 1 (24-32h), metaphase 2 (36-42h), versus oocytes from non-pregnant donors: metaphase 1 (24h), metaphase 2 (32-48h) (P<0.05). The level of apoptotic cells in cumuli of matured COCs increased during IVM and was higher in matured COCs from non-pregnant donors for each time point during IVM (P<0.01). Camel oocytes meiosis during IVM is accompanied by a drastic increase of apoptosis in the surrounding cumulus cells 0-32 and 0-24h during IVM, respectively for pregnant and non-pregnant donors. The oocytes of pregnant camels require 36h of maturation to reach levels of >50% metaphase 2 stage in comparison to oocytes from non-pregnant donors where 32h are sufficient. The earlier onset of apoptosis in the COCs derived from non-pregnant donors possibly determines the faster progression of the oocytes through the final stages of meiosis.  相似文献   
28.
Based on the supposition that lamprey GnRH-III (lGnRH-III) elicits FSH releasing activity in swine, synthetic lGnRH-III (peforelin, Maprelin® XP10) was used in puberal estrus synchronized gilts. The secretion of reproductive hormones FSH, LH, estradiol and progesterone was analyzed, and follicle growth and ovulation recorded. Altogether, 24 German Landrace gilts were treated after an 18-day long synchronization of the estrus cycle with Regumate® as follows: 48 h after the last Regumate® feeding they received im either 150 μg Maprelin® XP10 (lGnRH-III, group Maprelin, n = 6), 50 μg Gonavet Veyx® (GnRH-I agonist, group GnRH, n = 6), 850 IE Pregmagon® (eCG, group eCG, n = 6) or saline (group Control, n = 6). Additionally, in eight gilts the concentrations of FSH and LH were analyzed after treatment with 150 μg Maprelin® XP10 (n = 3), 50 μg Gonavet Veyx® (n = 3) or saline (n = 2) at mid-cycle (day 10 of the estrus cycle). Blood samples were collected via implanted jugular vein catheters. Ovarian features were judged endoscopically at the end of the Regumate® feeding and on days 5 and 6 after treatment. Maprelin® XP10 had no effect on FSH release in gilts; neither at the pre-ovulatory period or at mid-cycle. Furthermore, LH levels were unaffected. In contrast, GnRH-I agonist stimulates FSH release, however less compared to LH secretion. LH secretion was induced by GnRH-I both during the follicular phase and at mid-cycle. Equine CG did not stimulate the release of pituitary hormones FSH and LH due to its direct action on the ovary. Increased estradiol concentrations during days 2 to 5 after Regumate® in all treatment groups indicated pre-ovulatory follicle growth in gilts. Equine CG stimulated a higher (P < 0.01) number of ovulatory follicles compared to the other treatment groups. All together, 83 to 100 % of gilts ovulated by day 6 post treatment. In summary, results of our study on reproductive hormone secretion do not provide evidence that synthetic lGnRH-III (Maprelin® XP10) selectively releases FSH in estrus synchronized gilts.  相似文献   
29.

Objective

The aim of this study was to describe treatment outcomes for multi-drug resistant tuberculosis (MDR-TB) outpatients on a standardized regimen in Nepal.

Methodology

Data on pulmonary MDR-TB patients enrolled for treatment in the Green Light Committee-approved National Programme between 15 September 2005 and 15 September 2006 were studied. Standardized regimen was used (8Z-Km-Ofx-Eto-Cs/16Z-Ofx-Eto-Cs) for a maximum of 32 months and follow-up was by smear and culture. Drug susceptibility testing (DST) results were not used to modify the treatment regimen. MDR-TB therapy was delivered in outpatient facilities for the whole course of treatment. Multivariable analysis was used to explain bacteriological cure as a function of sex, age, initial body weight, history of previous treatment and the region of report.

Principal Findings

In the first 12-months, 175 laboratory-confirmed MDR-TB cases (62% males) had outcomes reported. Most cases had failed a Category 2 first-line regimen (87%) or a Category 1 regimen (6%), 2% were previously untreated contacts of MDR-TB cases and 5% were unspecified. Cure was reported among 70% of patients (range 38%–93% by Region), 8% died, 5% failed treatment, and 17% defaulted. Unfavorable outcomes were not correlated to the number of resistant drugs at baseline DST. Cases who died had a lower mean body weight than those surviving (40.3 kg vs 47.2 kg, p<0.05). Default was significantly higher in two regions [Eastern OR = 6.2; 95%CL2.0-18.9; Far West OR = 5.0; 95%CL1.0-24.3]. At logistic regression, cure was inversely associated with body weight <36 kg [Adj.OR = 0.1; 95%CL0.0-0.3; ref. 55–75 kg] and treatment in the Eastern region [Adj.OR = 0.1; 95%CL0.0-0.4; ref. Central region].

Conclusions

The implementation of an ambulatory-based treatment programme for MDR-TB based on a fully standardized regimen can yield high cure rates even in resource-limited settings. The determinants of unfavorable outcome should be investigated thoroughly to maximize likelihood of successful treatment.  相似文献   
30.
Ohne Zusammenfassung  相似文献   
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