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91.
Polycystic ovary syndrome (PCOS) is the most common hormonal imbalance disease in reproductive‐aged women. Its basic characteristics are ovulatory dysfunction and ovarian overproduction of androgens that lead to severe symptoms such as insulin resistance, hirsutism, infertility, and acne. Notwithstanding the disease burden, its underlying mechanisms remain unknown, and no causal therapeutic exists. In recent years, further studies showed that inflammation processes are involved in ovulation and play a key role in ovarian follicular dynamics. Visceral adipose tissue can cause inflammatory response and maintenance of the inflammation state in adipocytes by augmented production of inflammatory cytokines, monocyte chemoattractant proteins, and recruitment of the immune cell. Therefore, the PCOS can be related to a low‐grade inflammation state and inflammatory markers. Investigating the inflammatory processes and mediators that contribute to the commencement and development of PCOS can be a critical step for better understanding the pathophysiology of the disease and its treatment through inhibition or control of related pathways. In the present review, we discuss the pathophysiological roles of chronic low‐grade inflammation mediators including inflammasome‐related cytokines, interleukin‐1β (IL‐1β), and IL‐18 in PCOS development.  相似文献   
92.
Abstract The plasmid-mediated TEM-1 and TEM-2 β-lactamases are the most commonly encountered among Gram-negative bacteria. They belong to molecular class A, and differ by one amino acid at position 39: TEM-1 have a glutamine and TEM-2 a lysine. Kinetic parameters ( k cat and K m) and catalytic efficiency ( k cat/ K m) of TEM-1 and TEM-2 β-lactamases are slightly, but significantly different. For all antibiotics except methicillin and cefazolin, the catalytic efficiency values of TEM-2 are clearly greater than that of TEM-1. Molecular modelling of TEM-2, when compared to that of TEM-1, showed an additional ionic bond between Lys-39 and Glu-281.  相似文献   
93.
94.
One of the major problems in industrial water systems is the generation of biofilm, which is resistant to antimicrobial agents and causes failure of sanitization policy. This work aimed to study the anti-biofilm activity of peracetic acid (PAA) at contact times and temperatures combinations. To this end, a 96-well microtiter-based calorimetric method was applied in in vitro biofilm production using Escherichia coli, isolated from the water supply system of a pharmaceutical plant. The phenotypic and phylogenetic tests confirmed that the isolated bacteria belong to strains of Escherichia coli. The anti-biofilm activity of peracetic acid on formed biofilm was investigated at concentrations of 0·15–0·5% for a contact time of 5–15 min at 20–60°C. The maximum biofilm formation by MTP method using an Escherichia coli isolate was achieved in 96-h incubation in TSB containing wells at 37°C. Biofilm formation rate shown to be high by the environmental isolate compared with that of standard strain. PAA at concentrations above 0·25%, the temperature of 40°C and a minimum of 10 min of contact time was effective in the eradication of biofilm in an MTP-based system.  相似文献   
95.
A comparative study of floral ontogeny and development was carried out on three genera (Marrubium L., Phlomis L., Stachys L.), representing three tribes of Lamioideae (Marrubieae, Phlomideae, Stachydeae) using epi-illumination light microscopy. The sequence of organ whorl appearance in all three genera is sepals, petals plus stamens, and carpels. Sepal appearance is reversed unidirectional starting from the adaxial side in all except Phlomis, which is unidirectional. Order of petal appearance is bidirectional in Marrubium and Stachys, and simultaneous in Phlomis. Stamens appear unidirectionally starting from the adaxial side in all except in Phlomis, which has an abaxial to adaxial unidirectional sequence. Significant developmental features distinguishing the three genera from each other include (1) weakly monosymmetric, elongated calyx tube, five-lobed corolla, divergent anthers with thecae transverse to the filament, unequally bifid stigma and ovary with glandular hairs in Marrubium; (2) actinomorphic hairy calyx, four-lobed corolla and unequally bifid stigma in Phlomis; and (3) glabrous calyx, equally bifid stigma and symmetric disc nectary in Stachys. Our results indicate some potential for floral ontogenetic features in delimiting the different tribes. The hypothetical evolutionary pathway of organogenesis sequences is discussed.  相似文献   
96.
Our goal was to design nanocarriers that specifically target and deliver therapeutics to polarized macrophages. Mannose receptors are highly overexpressed on polarized macrophages. In this study, we constructed Pluronic® -F127 polymer and tannic acid (TA) based nanoparticles (F127-TA core nanoparticles) with varying mannose densities. The particle size of the optimized mannose-decorated F127-TA hybrid nanoparticles (MDNPs) was found to be ~ 265 nm with a negative zeta potential of ~ ? 4.5 mV. No significant changes in the size and zeta potentials of nanoparticles were observed, which demonstrated structural integrity and stability of the nanoformulation. Physicochemical characteristics of MDNPs were evaluated by FTIR and TGA and demonstrated the presence of mannose units on surface nanoparticles. A mannose-dependent cellular targeting and uptake of MDNPs was found in U937 macrophages. The uptake process was found to vary directly with time and volume of MDNPs nanoparticles. The uptake pattern is higher in M2 than M1. This behavior was also evident from the instantaneous and superior binding profile of M2 macrophage lysate protein with MDNPs over that of M1 macrophage lysate protein. These results demonstrated that an appropriate mannose ligand density was confirmed, suggesting efficient targeting of M2. Altogether, these data support that the MDNPs formulation could serve as a targeted therapeutic guide in the generation of nanomedicine to treat various conditions as an anti-inflammation therapy.  相似文献   
97.
Malaria remains a major public health problem in many countries. Unlike influenza and HIV, where diversity in immunodominant surface antigens is understood geographically to inform disease surveillance, relatively little is known about the global population structure of PfEMP1, the major variant surface antigen of the malaria parasite Plasmodium falciparum. The complexity of the var multigene family that encodes PfEMP1 and that diversifies by recombination, has so far precluded its use in malaria surveillance. Recent studies have demonstrated that cost-effective deep sequencing of the region of var genes encoding the PfEMP1 DBLα domain and subsequent classification of within host sequences at 96% identity to define unique DBLα types, can reveal structure and strain dynamics within countries. However, to date there has not been a comprehensive comparison of these DBLα types between countries. By leveraging a bioinformatic approach (jumping hidden Markov model) designed specifically for the analysis of recombination within var genes and applying it to a dataset of DBLα types from 10 countries, we are able to describe population structure of DBLα types at the global scale. The sensitivity of the approach allows for the comparison of the global dataset to ape samples of Plasmodium Laverania species. Our analyses show that the evolution of the parasite population emerging out of Africa underlies current patterns of DBLα type diversity. Most importantly, we can distinguish geographic population structure within Africa between Gabon and Ghana in West Africa and Uganda in East Africa. Our evolutionary findings have translational implications in the context of globalization. Firstly, DBLα type diversity can provide a simple diagnostic framework for geographic surveillance of the rapidly evolving transmission dynamics of P. falciparum. It can also inform efforts to understand the presence or absence of global, regional and local population immunity to major surface antigen variants. Additionally, we identify a number of highly conserved DBLα types that are present globally that may be of biological significance and warrant further characterization.  相似文献   
98.
This paper proposes dynamic treatment regimes (DTRs) as effective individualized treatment strategies for managing chronic periodontitis. The proposed DTRs are studied via SMARTp —a two-stage sequential multiple assignment randomized trial (SMART) design. For this design, we propose a statistical analysis plan and a novel cluster-level sample size calculation method that factors in typical features of periodontal responses such as non-Gaussianity, spatial clustering, and nonrandom missingness. Here, each patient is viewed as a cluster, and a tooth within a patient's mouth is viewed as an individual unit inside the cluster, with the tooth-level covariance structure described by a conditionally autoregressive structure. To accommodate possible skewness and tail behavior, the tooth-level clinical attachment level (CAL) response is assumed to be skew-t, with the nonrandomly missing structure captured via a shared parameter model corresponding to the missingness indicator. The proposed method considers mean comparison for the regimes with or without sharing an initial treatment, where the expected values and corresponding variances or covariance for the sample means of a pair of DTRs are derived by the inverse probability weighting and method of moments. Simulation studies are conducted to investigate the finite-sample performance of the proposed sample size formulas under a variety of outcome-generating scenarios. An R package SMARTp implementing our sample size formula is available at the Comprehensive R Archive Network for free download.  相似文献   
99.
Biological Trace Element Research - This study evaluates serum copper and magnesium and total antioxidant capacity levels in PCOS patients. In this regard, the probable association of copper and...  相似文献   
100.
Matrix metalloproteinase (MMP)‐2 and ‐9 play important roles in the progression of atherosclerosis. This study aims to determine whether MMP‐2 and ‐9 content in the fibrotic caps of atherosclerotic plaque is correlated with plaque autofluorescence. A time‐resolved laser‐induced fluorescence spectroscopy (TR‐LIFS) system was used to measure the autofluorescence and assess the biochemical composition of human plaques obtained from carotid endarterectomy. Results presented here demonstrate for the first time the ability to characterize the biochemical composition as it relates to MMP‐2 and ‐9 content in the atherosclerotic plaque cap using a label‐free imaging technique implemented with a fiberoptic TR‐LIFS system. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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