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31.
Cousinia kermanensis sp. nov. (sect. Congestae Bunge) and C. pulcherantha sp. nov. (sect. Leiocaules Bunge) are described from Kerman in southeastern Iran. These species are compared to their closest related species, C. decurrens Regel and C. oophora Rech. f., respectively. The habitat of C. kermanensis is lowland mountains or hills with poor soils inside the steppe of Artemisia sieberi Besser. Cousinia pulcherantha grows on highland slopes of mountains with deep soils inside the steppe of Artemisia aucheri Boiss. Illustrations of the new species are presented.  相似文献   
32.
A series of 5-(nitroaryl)-1,3,4-thiadiazoles bearing certain sulfur containing alkyl side chain similar to pendent residue in tinidazole molecule were synthesized and evaluated against Helicobacter pylori using disk diffusion method. The synthesized compounds were also evaluated for their antibacterial, antifungal and cytotoxic effects. Study of the structure-activity relationships of this series of compounds indicated that both the structure of the nitroaryl unit and the pendent group on 2-position of 1,3,4-thiadiazole ring dramatically impact the anti-H. pylori activity. While compound 7a containing 2-[2-(ethylsulfonyl)ethylthio]-side chain from nitrothiophene series was the most potent compound tested against clinical isolates of H. pylori, however, nitroimidazoles 6c and 7c were found to be more promising compounds because of their respectable anti-H. pylori activity besides less cytotoxic effects.  相似文献   
33.
Keratin intermediate filaments play an important role in maintaining the integrity of the skin structure. Understanding the importance of this subject is possible with the investigation of keratin defects in epidermolysis bullosa simplex (EBS). Nowadays, in addition to clinical criteria, new molecular diagnostic methods, such as next generation sequencing, can help to distinguish the subgroups of EBS more precisely. Because the most important and most commonly occurring molecular defects in these patients are the defects of keratins 5 and14 (KRT5 and KRT14), comprehending the nature structure of these proteins and their involved processes can be very effective in understanding the pathophysiology of this disease and providing new and effective therapeutic platforms to treat it. Here, we summarized the various aspects of the presence of KRT5 and KRT14 in the epidermis, their relation to the incidence and severity of EBS phenotypes, and the processes with which these proteins can affect them.  相似文献   
34.
35.
The structure and speciation of the complexes formed between mercury(II) ions and glutathione (GSH = L-glutamyl-L-cysteinyl-glycine) have been studied for a series of alkaline aqueous solutions (\( C_{{{\text{Hg}}^{{2 + }}}}\,{\sim18\,{\rm{mmol}}\,{\rm{{dm^{-3}}}}}\) and C GSH = 40–200 mmol dm?3 at pH ~10.5) by means of extended X-ray absorption fine structure (EXAFS) and 199Hg NMR spectroscopy at ambient temperature. The dominant complexes are [Hg(GS)2]4? and [Hg(GS)3]7?, with mean Hg–S bond distances of 2.32(1) and 2.42(2) Å observed in digonal and trigonal Hg–S coordination, respectively. The proportions of the Hg2+–glutathione complexes were evaluated by fitting linear combinations of model EXAFS oscillations representing each species to the experimental EXAFS spectra. The [Hg(GS)4]10? complex, with four sulfur atoms coordinated at a mean Hg–S bond distance of 2.52(2) Å, is present in minor amounts (<30%) in solutions containing a large excess of glutathione (C GSH ≥ 160 mmol dm?3). Comparable alkaline mercury(II) cysteine (H2Cys) solutions were also investigated and a reduced tendency to form higher complexes was observed, because the deprotonated amino group of Cys2? allows the stable [Hg(S,N-Cys)2]2? chelate to form. The effect of temperature on the distribution of the Hg2+–glutathione complexes was studied by comparing the EXAFS spectra at ambient temperature and at 25 K of a series of glycerol/water (33/67, v/v) frozen glasses with \( C_{{{\text{Hg}}^{{2 + }} }} \,{\sim7\,{\rm{mmol}}\,{\rm{{dm^{-3}}}}} \) and C GSH = 16–81 mmol dm?3. Complexes with high Hg–S coordination numbers, [Hg(GS)3]7? and [Hg(GS)4]10?, became strongly favored when just a moderate excess of glutathione (C GSH ≥28 mmol dm?3) was used in the glassy samples, as expected for a stepwise exothermic bond formation. Addition of glycerol had no effect on the Hg(II)–glutathione speciation, as shown by the similarity of the EXAFS spectra obtained at room temperature for two parallel series of Hg(II)-glutathione solutions with \( C_{{{\text{Hg}}^{{2 + }} }} \,{\sim7\,{\rm{mmol}}\,{\rm{{dm^{-3}}}}},\) with and without 33% glycerol. Also, the 199Hg NMR chemical shifts of a series of ~18 mmol dm?3 mercury(II) glutathione solutions with 33% glycerol were not significantly different from those of the corresponding series in aqueous solution.  相似文献   
36.
BACKGROUND: rac-Fenoterol is a beta2-adrenoceptor agonist (beta2-AR) used in the treatment of asthma. It has two chiral centers and is marketed as a racemic mixture of R,R'- and S,S'-fenoterol (R-F and S-F). Here we report the separation of the R-F and S-F enantiomers and the evaluation of their binding to and activation of the beta2-AR. METHODS: R-F and S-F were separated from the enantiomeric mixture by chiral chromatography and absolute configuration determined by circular dichroism. Beta2-AR binding was evaluated using frontal affinity chromatography with a stationary phase containing immobilized membranes from HEK-293 cells that express human beta2-AR and standard membrane binding studies using the same membranes. The effect of R-F and S-F on cardiomyocyte contractility was also investigated using freshly isolated adult rat cardiomyocytes. RESULTS: Chiral chromatography of rac-fenoterol yielded separated peaks with an enantioselectivity factor of 1.21. The less retained peak was assigned the absolute configuration of S-F and the more retained peak R-F. Frontal chromatography using membrane-bound beta2-AR as the stationary phase and rac-3H-fenoterol as a marker ligand showed that addition of increasing concentrations of R-F to the mobile phase produced concentration-dependent decreases in rac-3H-fenoterol retention, while similar addition of S-F produced no change in rac-3H-fenoterol retention. The calculated dissociation constant of R-F was 472 nM and the number of available binding sites 176 pmol/column, which was consistent with the results from the membrane binding study 460 +/- 55 nM (R-F) and 109,000 +/- 10,400 nM (S-F). In the cardiomyocytes, R-F increased maximum contractile response from (265 +/- 11.6)% to (306 +/- 11.8)% of resting cell length (P < 0.05) and reduced EC50 from -7.0 +/- 0.270 to -7.1 +/- 0.2 log[M] (P < 0.05), while S-F had no significant effect. DISCUSSION: Previous studies have shown that rac-fenoterol acts as an apparent beta2-AR/G(s) selective agonist and fully restores diminished beta2-AR contractile response in cardiomyocytes from failing hearts of spontaneously hypertensive rats (SHR). Here we report the separation of the enantiomers of rac-fenoterol and that R-F is the active component of rac-fenoterol. Further evaluation of R-F will determine if it has enhanced selectivity and specificity for beta2-AR/G(s) activation and if it can be used in the treatment of congestive heart failure.  相似文献   
37.
During the recent years, ethomedicine has attracted a great deal of attention among the investigators throughout the world. Although ethnomedicine seeks, in the first place, to compensate for a biological need through providing cures for disorders, it, however, is of a cultural nature, too, in that it investigates people's behaviors and reactions toward health and the issues related to it. Consequently, traditional health must be counted as a component of a society's culture. Investigations of people's views toward traditional medicine are capable of throwing light on acquaintance with their conducts, customs, traditions and behaviors, as well as the social-economic conditions prevailing in their environment. In addition, such investigations of public medicine bring about familiarities with gradual developments in traditional medical methodologies as introduced by culture, economic, or social factors, first into the society, then medicine. Familiarizations with cultural diversities in relation to medicine are the end results. The present paper comprise an anthropological approach toward investigation of ethnomedical practiced by women of Uremia (North-West, Iran).  相似文献   
38.
Biomechanics and Modeling in Mechanobiology - Bloodstream infection (BSI) is a life-threatening infection that causes more than 80,000 deaths and more than 500,000 infections annually in North...  相似文献   
39.

Background:

During the last two decades, significant advances have been made in the fields of lactococcal genetics and protein expression. Lactococcus lactis (L. lactis) is an effective vector for protein expression and can be used as an antigen delivery system. Hence, L. lactis is an ideal candidate for mucosal immunotherapy. Profilin (Che a 2), the major allergen in Chenopodium album, is one of the most important causes of allergic diseases in desert and semi-desert areas, especially in Iran, Saudi Arabia, and Kuwait that was cloned and expressed in L. lactis for the first time.

Methods:

To construct L. lactis that expressed Che a 2, a DNA sequence was cloned and used to transform bacteria. Expression of Che a 2 was analyzed via monitoring of related RNA and protein. Hydrophobicity, adherence to HT-29 cells, antibiotic resistance, resistance to gastrointestinal contents, pH, and bile salt in recombinant and native L. lactis were evaluated.

Results:

Immunoblot analyses demonstrated that recombinant Che a 2 is expressed as a 32 kDa dimeric protein immunological studies showed it can bind human IgE. Both native and recombinant bacteria were sensitive to low pH and simulated gastric conditions. Bacterial survival was reduced 80-100% after 2 h of exposure to pH 1.5-2. Both native and recombinant bacteria were able to grow in 0.3 and 2% bile salts. After incubation of recombinant L. lactis in simulated gastric and intestinal juices for one and two hours, respectively, cell survival was reduced by 100%. Adhesion capability in both strains was minimal and there were no significant differences in any of our tests between native and recombinant bacteria.

Conclusion:

Successfully recombinant L. lactis with capability of expression Che a 2 was produced and revealed it is sensitive to gastrointestinal contents. Key Words: Recombinant L. lactis, Probiotic bacteria, Chenopodium pollen allergen, Oral vaccines  相似文献   
40.

Background

Major depressive disorder (MDD) has been associated with adverse medical consequences, including cardiovascular disease and osteoporosis. Patients with MDD may be classified as having melancholic, atypical, or undifferentiated features. The goal of the present study was to assess whether these clinical subtypes of depression have different endocrine and metabolic features and consequently, varying medical outcomes.

Methods

Premenopausal women, ages 21 to 45 years, with MDD (N = 89) and healthy controls (N = 44) were recruited for a prospective study of bone turnover. Women with MDD were classified as having melancholic (N = 51), atypical (N = 16), or undifferentiated (N = 22) features. Outcome measures included: metabolic parameters, body composition, bone mineral density (BMD), and 24 hourly sampling of plasma adrenocorticotropin (ACTH), cortisol, and leptin.

Results

Compared with control subjects, women with undifferentiated and atypical features of MDD exhibited greater BMI, waist/hip ratio, and whole body and abdominal fat mass. Women with undifferentiated MDD characteristics also had higher lipid and fasting glucose levels in addition to a greater prevalence of low BMD at the femoral neck compared to controls. Elevated ACTH levels were demonstrated in women with atypical features of depression, whereas higher mean 24-hour leptin levels were observed in the melancholic subgroup.

Conclusions

Pre-menopausal women with various features of MDD exhibit metabolic, endocrine, and BMD features that may be associated with different health consequences.

Trial Registration

ClinicalTrials.gov NCT00006180  相似文献   
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