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971.
A new fluorimetric procedure is described for analysis of milnacipran in its bulk, tablet dosage forms, as well as in biological human samples such as plasma and urine. The suggested method relies on the construction of a derivative with strong fluorescence called dihydropyridine derivative. This derivative resulted from the interaction of the primary amino group in the studied drug and acetylacetone/formaldehyde in McIlvaine buffer (pH 5). The fluorescent dihydropyridine derivative was measured at 470 nm. Influences of experimental variables namely pH, reagent concentration and temperature were examined and optimized. The calibration curve showed linearity over the range of 0.15–1.25 μg ml?1 of milnacipran with an R2 value of 0.9998. The detection limit was 0.02 μg ml?1 and the determination limit was 0.07 μg ml?1. The developed procedure was successfully used in the assay of the studied drug in Avermilan® tablets with excellent selectivity. In addition, the reaction was applied to estimate the drug in spiked human plasma and urine with mean percentage recoveries of 100.04 ± 1.61 and 99.78 ± 0.81% for urine and plasma, respectively.  相似文献   
972.
Plasmonics - In this paper, we have proposed a new npn-type design of a CMOS-compatible metal/semiconductor/insulator/metal (MSIM) plasmonic structure, to be used as a different geometry to...  相似文献   
973.
974.

Obsessive–compulsive disorder (OCD) is an important neuropsychiatric disorder worldwide. Common treatments of OCD include serotonergic antidepressants, which can cause potentially serious side effects. We assessed the effects of Lactobacillus casei (L. casei) Shirota consumption in an animal model of OCD. OCD-like symptoms were induced in rats by the chronic injection of the D2/D3 dopamine agonist quinpirole hydrochloride. Rats were classified into five groups of 6 rats. Four groups were injected chronically with quinpirole (0.5 mg/kg, twice weekly for 5 weeks). They were fed with L. casei Shirota (109 CF/g, daily for 4 weeks) (group 1), fluoxetine (10 mg/kg, daily for 4 weeks) (group 2), combination of L. casei Shirota and fluoxetine (group 3), and normal saline (positive control group). The last group did not receive dopamine agonist and was only injected with saline (negative control group). Expression levels of brain-derived neurotrophic factor (Bdnf), solute carrier family 6 member 4 (Slc6a4), and 5-hydroxytryptamine receptor type 2A (Htr2a) were assessed in orbitofrontal cortex tissues of all rats. Behavioral tests showed improvement of OCD signs in rats treated with L. casei Shirota, fluoxetine, and a combination of drugs. Quantitative PCR analysis showed a remarkable decrease in the expression of Bdnf and an increase in the expression of Htr2a in quinpirole-treated rats. After treatment with L. casei Shirota and fluoxetine, the expression level of Bdnf was increased remarkably, whereas Htr2a expression was decreased. The current study showed the effectiveness of L. casei Shirota in the treatment of OCD in a rat model. The beneficial effects of this probiotic are possibly exerted through the modulation of serotonin-related genes expression.

  相似文献   
975.
The Gram‐negative bacterium Erwinia amylovora causes fire blight, an economically important disease of apples and pears. Elongation factor P (EF‐P) is a highly conserved protein that stimulates the formation of the first peptide bond of certain proteins and facilitates the translation of certain proteins, including those with polyproline motifs. YjeK and YjeA are two enzymes involved in the essential post‐translational β‐lysylation of EF‐P at a conserved lysine residue, K34. EF‐P, YjeA and YjeK have been shown to be essential for the full virulence of Escherichia coli, Salmonella species and Agrobacterium tumefaciens, with efp, yjeA and yjeK mutants having highly similar phenotypes. Here, we identified an E. amylovora yjeK::Tn5 transposon mutant with decreased virulence in apple fruit and trees. The yjeK::Tn5 mutant also showed pleiotropic phenotypes, including reduced growth in rich medium, lower extracellular polysaccharide production, reduced swimming motility and increased chemical sensitivity compared with the wild‐type, whilst maintaining wild‐type level growth in minimal medium. All yjeK::Tn5 mutant phenotypes were complemented in trans with a plasmid bearing a wild‐type copy of yjeK. Comprehensive, quantitative proteomics analyses revealed numerous, environmentally dependent changes in the prevalence of a wide range of proteins, in higher abundance and lower abundance, in yjeK::Tn5 compared with the wild‐type, and many of these alterations could be linked to yjeK::Tn5 mutant phenotypes. The environmental dependence of the yjeK::Tn5 mutant proteomic alterations suggests that YjeK could be required for aspects of the environmentally dependent regulation of protein translation. YjeK activity may be critical to overcoming stress, including the challenging host environment faced by invading pathogenic bacteria.  相似文献   
976.
Abstract The subtypes of meningococci are defined by antigenic determinants on the class 1 outer membrane proteins. The established subtypes, designated by P1 and a number according to the prototype reference strain on which they were first recognized by monoclonal antibodies, includes P1.2, P1.9, P1.15 and P1.16.
We have investigated more prototype reference strains, using new monoclonal antibodies, and identified the new subtypes P1.1, P1.6 and P1.1,16. The P1.1,16 epitope is found on both the P1.1 and the P1.16 reference strains, but not on all P1.1 and P1.16 strains and can occur independently from the P1.1 and the P1.16 epitopes. It appears that class 1 outer membrane proteins contain at least two independent subtype-specific epitopes. For clarity, we now redefine P1.1,16 as P1.7, permitting thus the identification of strains of P1.1, P1.1,7, P1.7, P1.7,16 and P1.16 subtypes. It can clearly be expected that more class 1 outer membrane protein determinants will be recognized as more monoclonal typing antibodies are produced. The monoclonal antibodies now available to us can subtype 80–90% of group B and C meningococci; they also react with group A meningococci, but not with other Neisseriae . The immunological dissection of these subtyping antigens will improve our understanding of the relationship between components of the bacteria and the induction or prevention of disease.  相似文献   
977.
Background:Menopause is a unique event in women''s life it usually occurs naturally, most often after age 50 when woman has not menstruated in 12 consecutive months. This study was planned to assess the relationship between Vitamin D3 level, PAI-1 and HCG in Babylon women at age <50 years as pre-menopausal and> 50 years as post-menopausal.Methods:The sample were selected from a group of pre- and post-menopausal women, 30 and 50 respectively. All the tests were evaluated to measure Vitamin D3 level, PAI-1 and HCG level. The sample was collected between July 2019 and January 2020 at Merjan medical city GIT and Liver Center, Babylon province, Iraq.Results:The result of current study revealed that there are significant differences in vitamin D3 level in various age categories within postmenopausal women (p= 0.02) also there is no significant differences in PAI-1 and HCG with in these two groups, p= 0.08 and 0.07, respectively. Also, there is significant negative correlation between vitamin D3 and PAI-1 in postmenopausal women (p. value is 0.01).Conclusion:Indeed, postmenopausal women regarded as elderly, but they have sufficient vitamin D3 and normal PAI-I levels as markers for normal non fibrosis status.Key Words: And PAI-1, HCG, Menopause, Vitamin D3  相似文献   
978.
To explore the prevalence of multidrug-resistant community-associated uropathogenic Escherichia coli (UPEC) and their virulence factors in Western Saudi Arabia. A total of 1,000 urine samples were examined for the presence of E. coli by selective plating on MacConkey, CLED, and sheep blood agar. Antimicrobial susceptibility patterns were determined using Vitek® 2 Compact (MIC) and the disc diffusion method with Mueller-Hinton agar. Genes encoding virulence factors (kpsMTII, traT, sat, csgA, vat, and iutA) were detected by PCR. The overall prevalence of UTI-associated E. coli was low, and a higher prevalence was detected in samples of female origin. Many of the isolates exhibited resistance to norfloxacin, and 60% of the isolates showed resistance to ampicillin. No resistance to imipenem, meropenem, or ertapenem was detected. In general, half of the isolates showed multiple resistance patterns. UPEC exhibited a weak ability to form biofilms, where no correlation was observed between multidrug resistance and biofilm-forming ability. All uropathogenic E. coli isolates carried the kpsMTII, iutA, traT, and csgA genes, whereas the low number of the isolates harbored the sat and vat genes. The diversity of virulence factors harbored by community-associated UPEC may render them more virulent and further explain the recurrence/relapse cases among community-associated UITs. To the best of our knowledge, this study constitutes the first exploration of virulence, biofilm-forming ability, and its association with multidrug resistance among UPEC isolates in Saudi Arabia. Further investigations are needed to elucidate the epidemiology of community-associated UPEC in Saudi Arabia. Open in a separate window  相似文献   
979.
Background:The fluctuation in serum caveolin-1 (Cav-1) concentrations is an important indicator of many diseases. Irrespective of the actual cause, a significant reduction of serum Cav-1 is associated with a significant increase in insulin secretion and hyperinsulinemia. The aim of the current study was to evaluate the relationship between serum Cav-1, serum vaspin and visfatin in newly diagnosed men with T2DM.Methods:Eighty-two newly diagnosed men with T2DM were matched for age and body mass indexes (BMIs) with a similar number of non-diabetic men. Serum Cav-1, vaspin and visfatin were assessed through enzyme-linked immunosorbent assay. Fasting serum glucose (FSG), glycohaemoglobin A1C (HbA1c) were both measured using automated method. In addition, waist-circumferences, waist-hip ratio, systolic (SBP), and diastolic blood pressure (DBP) were also obtained.Results:Serum concentration of Cav-1(ng/mL) was significantly low in men newly diagnosed with T2DM, (2.334±0.7627) compared with non-diabetic controls (4.321±1.143), p< 0.0001. In contrast, patients with T2DM exhibited significantly higher serum concentrations of vaspin and visfatin (ng/mL), 142.4±60.53) and 2.99±1.091), than controls, 81.53±39.32) and 1.456±0.654), respectively, p< 0.0001. Expectedly, patients with T2DM have significantly higher FSG, HbA1c, systolic blood pressure (SBP), and diastolic blood pressure (DBP).Conclusion:There was an inverse significant relationship between Cav-1 and vaspin, visfatin, HbA1c, FSG, and hypertension. This study suggests that serum Cav-1 can be used as a diagnostic marker to predict T2DM in individuals and families under high risk. Key Words: Caveolin-1, HbA1c, Insulin resistance, T2DM, Vaspin, Visfatin  相似文献   
980.
Here we determined the structure of a cold active family IV esterase (EstN7) cloned from Bacillus cohnii strain N1. EstN7 is a dimer with a classical α/β hydrolase fold. It has an acidic surface that is thought to play a role in cold-adaption by retaining solvation under changed water solvent entropy at lower temperatures. The conformation of the functionally important cap region is significantly different to EstN7''s closest relatives, forming a bridge-like structure with reduced helical content providing greater access to the active site through more than one substrate access tunnel. However, dynamics do not appear to play a major role in cold adaption. Molecular dynamics at different temperatures, rigidity analysis, normal mode analysis and geometric simulations of motion confirm the flexibility of the cap region but suggest that the rest of the protein is largely rigid. Rigidity analysis indicates the distribution of hydrophobic tethers is appropriate to colder conditions, where the hydrophobic effect is weaker than in mesophilic conditions due to reduced water entropy. Thus, it is likely that increased substrate accessibility and tolerance to changes in water entropy are important for of EstN7''s cold adaptation rather than changes in dynamics.  相似文献   
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