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101.
Human preterm labor (PL) is the single most significant problem in modern Obstetrics and Gynecology, affecting approximately 10% of pregnancies worldwide, constituting the leading cause of perinatal mortality and morbidity, and contributing significantly to chronic childhood disease. Currently, our molecular understanding of PL remains staggeringly inadequate to reliably diagnose or rationally intervene in PL events; several molecular alterations have been implicated in PL, but these have proven of limited value as diagnostic/prognostic markers. The majority of PL events remain spontaneous and unpredictable: critical care emergencies. Here, we apply functional proteomics to dissect molecular mechanisms of human PL. Human placental tissue was collected in clearly differentiated cases of preterm and term labor. Highly refined two-dimensional gel electrophoresis (2DE) was used for protein separation, coupled with automated differential gel image analysis to compare the resulting proteomic maps. For this initial study, only the most important protein differences were selected for further analysis, that is, proteins that were unique to one sample, and absent from the other, with 100% reproducibility across the sample population. In total, 11 such proteins were identified by tandem mass spectrometry, falling into three distinct functional classes: structural/cytoskeletal components, ER lumenal proteins with enzymatic or chaperone functions, and proteins with anticoagulant properties. These expression changes form the groundwork for further molecular investigation of this devastating medical condition. This approach therefore holds the potential not only to define the underlying molecular components, but also to identify novel diagnostic tools and targets for rational drug intervention.  相似文献   
102.
We determined the effects of past and future climate changes on the distribution of the Montivipera raddei species complex (MRC) that contains rare and endangered viper species limited to Iran, Turkey and Armenia. We also investigated the current distribution of MRC to locate unidentified isolated populations as well as to evaluate the effectiveness of the current network of protected areas for their conservation. Present distribution of MRC was modeled based on ecological variables and model performance was evaluated by field visits. Some individuals at the newly identified populations showed uncommon morphological characteristics. The distribution map of MRC derived through modeling was then compared with the distribution of protected areas in the region. We estimated the effectiveness of the current protected area network to be 10%, which would be sufficient for conserving this group of species, provided adequate management policies and practices are employed. We further modeled the distribution of MRC in the past (21,000 years ago) and under two scenarios in the future (to 2070). These models indicated that climatic changes probably have been responsible for an upward shift in suitable habitats of MRC since the Last Glacial Maximum, leading to isolation of allopatric populations. Distribution will probably become much more restricted in the future as a result of the current rate of global warming. We conclude that climate change most likely played a major role in determining the distribution pattern of MRC, restricting allopatric populations to mountaintops due to habitat alterations. This long-term isolation has facilitated unique local adaptations among MRC populations, which requires further investigation. The suitable habitat patches identified through modeling constitute optimized solutions for inclusion in the network of protected areas in the region.  相似文献   
103.
Thrips tabaci is a polyphagous pest that attacks many different crop and ornamental plant species. Recently, the need to reduce the use of insecticides in the control of thrips is more and more increasing. On that account, the possibility to make use of the entomopathogenic fungus Verticillium lecanii (DAOM198499) was evaluated in laboratory conditions. Suspension of 10(3) to 10(7) conidia/ml grown in liquid culture medium with a control (distilled water) treated on second larval stage of T. tabaci in controlled condition (16L: 8D photoperiod, 25 +/- 1 degrees C temperature, 98% RH in first 48h and 70% RH in next days). Preliminary results showed that mortality in lethal suspension (10(7) conidia/ml) of V. lecanii after 24 hours and 2-7 days in lower suspension appears. This suggests that strine DAOM 198499 of V. lecanii has the ability to control T. tabaci in greenhouse conditions.  相似文献   
104.
Pancreatic amyloid is formed by the aggregation of the 37-residue islet amyloid polypeptide (IAPP) in type II diabetes patients and is cytotoxic. Pancreatic amyloid deposits are found in more than 95 % of type II diabetes patients and their formation is strongly associated with disease progression. IAPP amyloid forms via a conformational transition of soluble IAPP into aggregated beta-sheets. We recently identified IAPP(22-27) (NFGAIL) as a minimum length sequence sufficient to self-associate into beta-sheet-containing amyloid fibrils. Here, we have used the NFGAIL model of the IAPP amyloid core as a structural template to design non-amyloidogenic derivatives of amyloidogenic sequences of IAPP that are able to interact with the native sequences and inhibit amyloid formation. The design of the derivatives was based on a simple, structure-based minimalistic and selective N-methylation approach. Accordingly, a minimum number of two amide bonds on the same side of the beta-strand of the amyloid core was N-methylated. This was expected to eliminate the two intermolecular backbone NH to CO hydrogen bonds which are critical for the extension of the beta-sheet dimers into multimers and amyloid. Other beta-strand "contact sides" remained intact allowing for the derivatives to interact with the native sequences. Double N-methylated derivatives of amyloidogenic and cytotoxic partial IAPP sequences generated included F(N-Me)GA(N-Me)IL, NF(N-Me)GA(N-Me)IL, SNNF(N-Me)GA(N-Me)IL, and SNNF(N-Me)GA(N-Me)ILSS and were found to be devoid of beta-sheet structure, amyloidogenicity and cytotoxicity according to Fourier transform-infrared spectroscopy (FT-IR), Congo red (CR) staining, electron microscopy (EM), and cell viability tests. The derivatives were able to interact with the native sequences and inhibit amyloid formation as shown by circular dichroism spectroscopy (CD), FT-IR and EM. Moreover, SNNF(N-Me)GA(N-Me)ILSS inhibited cytotoxicity of SNNFGAILSS and is thus the first reported inhibitor of IAPP amyloid formation and cytotoxicity. Our results demonstrate the validity of the design approach for IAPP and suggest that it may find application in understanding the structural features of amyloid formation and in the development of inhibitors of amyloid formation and cytotoxicity of other amyloidogenic polypeptides as well.  相似文献   
105.
The major endogenous cytokinins, Z, ZR, DHZ, DHZR, iP and iPR in pistachio seedlings (Pistacia vera L. cv. Ohadi) were purified by HPLC and their identities confirmed using GC-MS. The aerial parts of two-year old pistachio seedlings including mature leaves, young leaves, lateral buds, debarked stems and bark were subjected to analysis. All of the above mentioned cytokinins were identified in the aerial parts except DHZ which was only present in mature leaves. Z-type cytokinins contributed almost 43% of the total cytokinins. ZR and DHZR were identified as the major ribosides and iP as the main base. The greatest concentration of ZR was detected in the bark, amounting to about 48%. DHZR and ZR constituted the major portion of the total cytokinins detected in both young and mature leaves while Z was detected as a minor cytokinin in leaves. The sharp increase of iP concentration during leaf maturation indicates that mature leaves are probably capable of de novo biosynthesis of cytokinins. The absence of DHZ (except in mature leaves) and the presence of considerable concentrations of DHZR in pistachio stems suggest that these tissues are able to metabolize DHZ to DHZR. The large amount of ZR in pistachio leaves suggests that root-derived ZR is transported into the leaves after loading into the xylem. The presence of high amounts of iP in pistachio lateral buds indicates that iP has been accumulated in these parts. The occurrence of a totally different cytokinin distribution pattern in buds, as compared with the other aerial parts, possibly results from their different metabolism.  相似文献   
106.

Background:

One of the main causes of sexually transmitted diseases is group B β- hemolytic streptococci (GBS) multiplying in the genital tracts. Penicillin is the most common drug for the treatment of infections caused by these bacteria, but in patients suffering from Penicillin allergy, Erythromycin and Clindamycin are used as alternative therapeutic drugs against GBS. Recently, resistance to these drugs has been reported more often. In this study, efforts have been made to determine the prevalence and antibiotic resistance of GBS.

Methods:

Modified Christie Atkins Munch-Petersen (CAMP) test was conducted on over 2400 samples of urine and discharge taken from vagina, urethra and prostate. The drug sensitivity was performed by double disk sensitivity tests to Bacitracin, Trimethoprim, and Sulfamethoxazole and then the resistant samples were investigated by E-test to determine the minimal inhibitory concentrations (MICs) value.

Results:

Twenty-three vaginal and 10 urethral discharge, 27urine and 6 prostatic secretion samples were GBS positive. The most symbiotic microorganisms with GBS were strains of Enterococci (90%), Staphylococcus saprophyticus (25%) and Candida albicans (6%). The disk diffusion method showed 18 cases with Penicillin resistance (MIC: 1.5 mg/ml).

Conclusion:

Taken together, GBS carriers’ rate in this study was found 20.65% (8.24% men and 12.4% women). Furthermore, findings showed high-level resistance to Erythromycin and Clindamycin.Key Words: Antibiotic resistance, Genitourinary system, Streptococcus agalactiae, minimal inhibitory concentration (MIC)  相似文献   
107.
In this study, a numerical investigation is performed to evaluate the effects of high-pressure sinusoidal and blast wave's propagation around and inside of a human external ear. A series of computed tomography images are used to reconstruct a realistic three-dimensional (3D) model of a human ear canal and the auricle. The airflow field is then computed by solving the governing differential equations in the time domain using a computational fluid dynamics software. An unsteady algorithm is used to obtain the high-pressure wave propagation throughout the ear canal which is validated against the available analytical and numerical data in literature. The effects of frequency, wave shape, and the auricle on pressure distribution are then evaluated and discussed. The results clearly indicate that the frequency plays a key role on pressure distribution within the ear canal. At 4 kHz frequency, the pressure magnitude is much more amplified within the ear canal than the frequencies of 2 and 6 kHz, for the incident wave angle of 90° investigated in this study, attributable to the ‘4-kHz notch’ in patients with noise-induced hearing loss. According to the results, the pressure distribution patterns at the ear canal are very similar for both sinusoidal pressure waveform with the frequency of 2 kHz and blast wave. The ratio of the peak pressure value at the eardrum to that at the canal entrance increases from about 8% to 30% as the peak pressure value of the blast wave increases from 5 to 100 kPa for the incident wave angle of 90° investigated in this study. Furthermore, incorporation of the auricle to the ear canal model is associated with centerline pressure magnitudes of about 50% and 7% more than those of the ear canal model without the auricle throughout the ear canal for sinusoidal and blast waves, respectively, without any significant effect on pressure distribution pattern along the ear canal for the incident wave angle of 90° investigated in this study.  相似文献   
108.
109.
Multiple sclerosis (MS) is the most common autoimmune disease characterized by multifocal areas of inflammatory demyelination within the central nervous system. Cytomegalovirus (CMV) has a complex pathobiology and in most cases is simply asymptomatic. There is some recent controversy over the role of CMV in the pathology of MS. The aim of this study was to evaluate active CMV infection and its effect on the humoral immunity in patients with MS. Serum, plasma, peripheral blood mononuclear cells (PBMCs), saliva and urine collected from MS patients (n=78) and healthy subjects (n=123) were screened for the presence of anti-CMV antibodies and CMV-DNA by nephelometric and PCR methods. Concentrations of total antibodies in MS subtypes were measured using both nephelometric and enzyme linked fluorescent assay (ELFA) techniques. The results extend the observation of an increased frequency of CMV-DNA in patients, in contrast with controls (p<0.001). Furthermore, systemic CMV infections were found in 25.5% of patients and only 3.2% of controls (p<0.001). There was significant difference in the titers of anti-CMV IgG and total IgE in patient and controls (P<0.001). These results support the hypothesis that CMV may contribute to MS thought to establish systemic infection process and induce immune response.  相似文献   
110.
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