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41.
Sixteen Arab lactating mares belonging to Al-Zahraa Arab Horse Stud underwent two ultrasound examinations at 3 weeks interval starting from the day of demonstration of foaling heat. In addition, daily blood samples were collected from parturition until after exhibiting first postpartum estrus (day 11) with daily observation of estrous signs. Both leptin and estradiol hormones were assayed. Mean day of foaling heat was 8.9 ± 0.9 day. Most mares came in foaling heat during days 9 and 10 had high conception rate compared to those who came in estrus earlier or later. Estradiol levels were high after day of foaling then decrease after expression of foaling heat. But leptin levels increase from day 8 to day 10 compared to other days before and after the first ovulation. A significant positive correlation was found between estradiol and leptin (r = 0.58, p < 0.025). The positive correlation between leptin and estradiol led us to suggest that leptin hormone plays an important role in ovulation of the first postpartum estrus in mares.  相似文献   
42.
43.

Aims

The aim of this study was to characterize Streptococcus agalactiae strains that were isolated from fishes in Malaysia using random amplified polymorphic DNA (RAPD) and repetitive extragenic palindromic PCR (REP‐PCR) techniques.

Methods and Results

A total of 181 strains of Strep. agalactiae isolated from red hybrid tilapia (Oreochromis sp.) and golden pompano (Trachinotus blochii) were characterized using RAPD and REP‐PCR techniques. Both the fingerprinting techniques generated reproducible band patterns, differing in the number and molecular mass amplicons. The RAPD technique displayed greater discriminatory power by its production of more complex binding pattern and divided all the strains into 13 groups, compared to 9 by REP‐PCR technique. Both techniques showed the availability to differentiate the genetic profiles of the strains according to their geographical location of origin. Three strains of Strep. agalactiae that were recovered from golden pompano showed a genetic dissimilarity from the strains isolated from red hybrid tilapia, while the strain of ATCC 27956 that recovered from bovine displayed a unique profile for both methods.

Conclusions

Both techniques possess excellent discriminative capabilities and can be used as a rapid means of comparing Strep. agalactiae strains for future epidemiological investigation.

Significance and Impact of the Study

Framework as the guideline in traceability of this disease and in the search for potential local vaccine candidates for streptococcosis in this country.  相似文献   
44.
In search of immunomodulatory constituents from the Eastern Nigeria mistletoe, Loranthus micranthus Linn, two new stigmastane steroids: stigmast-7,20 (21)-diene-3β-hydroxy-6-one (1) and 3β-hydroxy-stigmast-23-ene (2); three (two new and one known) lupeol-based triterpenoid esters: 7β,15α-dihydroxyl-lup-20(29)-ene-3β-palmitate (3), 7β,15α-dihydroxyl-lup-20(29)-ene-3β-stearate (4) and 7β,15α-dihydroxyl-lup-20(29)-ene-3β-eicosanoate (5) were isolated and characterized following bioactivity-guided fractionation. The new compounds, 1, 2, 4 and 5 at concentrations of 10, 25 and 100 μg/ml were subjected to cell proliferation and early activation marker (CD69) expression studies in C57Bl/6 mice splenocytes using flow cytometry techniques against Lipopolysaccharide (LPS; 10 μg/ml) and Concanavalin A (ConA; 2 μg/ml) standards. The stigmastane steroids (1 and 2) at the highest concentration of 100 μg/ml showed statistically significantly (p < 0.05) stimulatory activity on the C57B1/6 splenocytes compared to the controls with values of 46 ± 0.76% and 43 ± 0.46% compared to 7.69 ± 0.41% recorded for the negative control. The novel lupeol esters, 4 and 5 at same concentration of 100 μg/ml exhibited lower stimulations of 30 ± 0.41% and 29 ± 0.17% respectively compared to the controls above. The CD69 expression assay at the above doses showed that all the compounds have minimal stimulation. The present study supports the observed immunomodulatory property of the Eastern Nigeria mistletoe and thus confirms the efficacy of this plant in mitigating against wide array of disease conditions orchestrated by immunodeficiency.  相似文献   
45.
Background and Objectives: Saussurea lappa (S. lappa) is an important species of the Asteraceae family with several purposes in traditional medicine. This study intended to explore the cytotoxic effect of S. lappa on HepG2 cancer cell proliferation. Materials and Methods: The effects of an S. lappa n-butanol extract on the induction of apoptosis were investigated by flow cytometry and mitochondrial cytochrome C-releasing apoptosis assay. Additionally, real-time PCR was employed to confirm apoptosis initiation. Further, qualitative estimation of the active constituent of S. lappa was done by gas chromatography–mass spectroscopy (GC–MS). Results: The cell viability study revealed that the n-butanol extract of S. lappa demonstrated potent cytotoxicity against HepG2 cancer cells, with an IC50 value of 56.76 μg/mL. Cell morphology with dual staining of acridine orange (AO)-ethidium bromide (EB) showed an increase in orange/red nuclei due to cell death by S. lappa n-butanol extract compared to control cells. Apoptosis, as the mode of cell death, was also confirmed by the higher release of cytochrome C from mitochondria, the increased expression of caspase-3 and bax, along with down regulation of Bcl-2. Conclusion: These findings conclude that S. lappa is a cause of hepatic cancer cell death through apoptosis and a potential natural source suggesting furthermore investigation of its active compounds that are responsible for these observed activities.  相似文献   
46.
Lipase secretion, extracellular lipolysis, and fatty acid uptake were quantified in the yeast Yarrowia lipolytica grown in the presence of olive oil and/or glucose. Specific lipase assays, Western blot analysis, and ELISA indicated that most of the lipase activity measured in Y. lipolytica cultures resulted from the YLLIP2 lipase. Lipase production was triggered by olive oil and, during the first hours of culture, most of the lipase activity and YLLIP2 immunodetection remained associated with the yeast cells. YLLIP2 was then released in the culture medium before it was totally degraded by proteases. Olive oil triglycerides were largely degraded when the lipase was still attached to the cell wall. The fate of lipolysis products in the culture medium and inside the yeast cell, as well as lipid storage, was investigated simultaneously by quantitative TLC–FID and GC analysis. The intracellular levels of free fatty acids (FFA) and triglycerides increased transiently and were dependent on the carbon sources. A maximum fat storage of 37.8% w/w of yeast dry mass was observed with olive oil alone. A transient accumulation of saturated FFA was observed whereas intracellular triglycerides became enriched in unsaturated fatty acids. So far, yeasts have been mainly used for studying the intracellular synthesis, storage, and mobilization of neutral lipids. The present study shows that yeasts are also interesting models for studying extracellular lipolysis and fat uptake by the cell. The quantitative data obtained here allow for the first time to establish interesting analogies with gastrointestinal and vascular lipolysis in humans.  相似文献   
47.
Stray cats are a common feature roaming the streets and alleys of Kuwait; they could be a source of parasites, including trematodes, that affect humans. A survey was conducted to identify feline trematodes and throw the light on their public health significance in Kuwait. Out of 240 stray cats trapped from different localities of Kuwait from June 2011 to May 2012, 59 (24.6%) were found to be infected with 14 species of trematodes. The most common were trematodes of the genus Heterophyes, particularly H. heterophyes and H. dispar that were found in respectively 15.8% and 10.8% of the cats examined. Other trematodes recorded, with lower prevalences, were Heterophyes nocens (2.9%), Haplorchis taichui (3.8%), Stictodora sawakinensis (2.1%), Stellantchasmus falcatus (1.6%), Echinochasmus japonicus (1.6%), and Mesostephanus dottrensi (1.3%). Centrocestus cuspidatus, Galactosomum fregatae, Ascocotyle sp., Mesostephanus appendiculatus, Haplorchis yokogawai, and Pygidiopsis genata showed the lowest prevalence (0.4%) and intensity. The majority of the trematodes are recorded for the first time in Kuwait and even in the Gulf region. The study reveals that stray cats are good indicators of fish-borne trematodes in the environment. As all trematodes recovered are zoonotic, their significance to public health should be considred.  相似文献   
48.
For decades, mesenchymal stem (MSCs) cells have been used for cardiovascular diseases as regenerative therapy. This review is an attempt to summarize the types of MSCs involved in myocardial infarction (MI) therapy, as well as its possible mechanisms effects, especially the paracrine one in MI focusing on the studies (human and animal) conducted within the last 10 years. Recently, reports showed that MSC therapy could have infarct‐limiting effects after MI in both experimental and clinical trials. In this context, various types of MSCs can help cardiac regeneration by either revitalizing the cardiac stem cells or revascularizing the arteries and veins of the heart. Furthermore, MSCs could produce paracrine growth factors that increase the survival of nearby cardiomyocytes, as well as increase angiogenesis through recruitment of stem cell from bone marrow or inducing vessel growth from existing capillaries. Recent research suggests that the paracrine effects of MSCs could be mediated by extracellular vesicles including exosomes. Exosomal microRNAs (miRNAs) released by MSCs are promising therapeutic hotspot target for MI. This could be attributed to the role of miRNA in cardiac biology, including cardiac regeneration, stem cell differentiation, apoptosis, neovascularization, cardiac contractility and cardiac remodeling. Furthermore, gene‐modified MSCs could be a recent promising therapy for MI to enhance the paracrine effects of MSCs, including better homing and effective cell targeted tissue regeneration. Although MSC therapy has achieved considerable attention and progress, there are critical challenges that remains to be overcome to achieve the most effective successful cell‐based therapy in MI.  相似文献   
49.
The Attwater's prairie chicken (APC; Tympanuchus cupido attwateri Bendire, 1894) has been a federally listed endangered species since 1967. Several captive propagation programs consisting of small populations are being used to keep this species from extinction. Fecal samples were collected from APCs in April 2007 and again in August 2008 from 2 separate captive propagation facilities in Texas after clinical signs of coccidiosis were observed. One Eimeria species was observed (Eimeria attwateri), which we describe as a putative new species. Sporulated oocysts are ellipsoidal, 30.0 × 18.4 (27.4-31.3 × 16.0-22.4) μm. Oocysts have a smooth wall 0.7 μm thick and lack both a micropyle and oocyst residuum, but 1 ellipsoidal polar granule is present, 2.3 × 1.9 (2.1-2.4 × 1.7-2.0) μm. Sporocysts have a nipple-like Stieda body with a rounded opposite end and are 14.0 × 7.1 (10.2-16.8 × 6.0-9.2) μm. The sporocysts contain a sporocyst residuum usually consisting of 2-4 dispersed globules, and each sporozoite contains 2 large posterior spheroid refractile bodies 3.4 μm wide. Nucleotide sequence amplified from the 18S rDNA does not match any DNA sequence information for publicly available Eimeria species, and phylogenetic reconstructions place this species with other eimerians from Galliformes. The discovery of a potentially pathogenic species of Eimeria in captive APCs is of great importance, and managers should be aware of the potential devastating effect(s) this parasite could have on the APC conservation programs.  相似文献   
50.
The interaction between a patient and a ventilator is the major determinant of the amount of respiratory muscle rest achieved by the machine. We are beginning to acquire a better understanding of the mechanisms that underlie this complex interaction, but this information has yet to be integrated into the routine clinical management of ventilator-supported patients. To achieve that goal, we need better techniques of detecting and monitoring patient-ventilation asynchrony, and the development of simple algorithms that can minimize its occurence. Finally, research is needed to determine the occurrence and importance of respiratory muscle fatigue during failed weaning attempts so as to better guide the timing and pace of the weaning process in problematic patients.  相似文献   
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