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31.
Molluscum contagiosum (MC) is caused by a double stranded DNA virus belonging to the pox virus family. MC lesions are usually pearly, dome shaped, small, discrete lesions with central umbilication. In HIV-positive patients atypical varieties are found. They may be large or nonumbilicated. Individual papules may join to form the agminate variety. This form is rare. Lesions of MC in healthy immunocompetent patients may occur at any part of the body including face, trunk, and limbs. Sexually active adults have lesions usually on the genitalia, pubis, and inner thigh, rarely on the face and scalp. We present a case of agminate MC occurring in a patient with acquired immunodeficiency disease responding to highly active antiretroviral therapy.  相似文献   
32.
In recent years, there has been significant increase in mobile phone users. With this, health concerns associated with the exposure to electromagnetic radiation are also increasing. Continuous exposure to electromagnetic (EM) radiation generated from mobile phone is one of the probable reasons behind increasing male infertility. EM radiations induce oxidative stress that leads to numerous changes in reproductive parameters. With this hypothesis, we studied the effect of 3G mobile phone radiations on the reproductive system of male Wistar rats. Adult rats were divided into two groups: control and radio frequency‐exposed. The animals were exposed to 3G mobile phone radiation for 45 days (2 hr/day) in specially designed exposure setup under standard conditions. Various biochemical and physiological parameters such as sperm count, sperm morphology, mitochondrial activity, lipid peroxidation, reactive oxygen species level and histopathological analysis were studied. Histopathological examination revealed a reduction in spermatogenic cells and alterations in sperm membrane. Significant increase in ROS and lipid peroxidation level with simultaneously decrease in sperm count, alterations in sperm tail morphology were observed in the exposed group. In conclusion, exposure to mobile phone radiations induces oxidative stress in male Wistar rats which may lead to alteration in sperm parameters and affects their fertility.  相似文献   
33.
Experimental focal cortical ischemic lesions consist of an ischemic core and a potentially salvageable peri-ischemic region, the ischemic penumbra. The activity of neurons and astrocytes is assumed to be suppressed in the penumbra because the electrical function is interrupted, but this is incompletely elucidated. Most experimental stroke studies used young adult animals, whereas stroke is prevalent in the elderly population. Using two-photon imaging in vivo, we here demonstrate extensive but electrically silent, spontaneous Ca2+ activity in neurons and astrocytes in the ischemic penumbra of 18- to 24-month-old mice 2–4 hr after middle cerebral artery occlusion. In comparison, stroke reduced spontaneous Ca2+ activity in neurons and astrocytes in adult mice (3–4 months of age). In aged mice, stroke increased astrocytic spontaneous Ca2+ activity considerably while neuronal spontaneous Ca2+ activity was unchanged. Blockade of action potentials and of purinergic receptors strongly reduced spontaneous Ca2+ activity in both neurons and astrocytes in the penumbra of old stroke mice. This indicates that stroke had a direct influence on mechanisms in presynaptic terminals and on purinergic signaling. Thus, highly dynamic variations in spontaneous Ca2+ activity characterize the electrically compromised penumbra, with remarkable differences between adult and old mice. The data are consistent with the notion that aged neurons and astrocytes take on a different phenotype than young mice. The increased activity of the aged astrocyte phenotype may be harmful to neurons. We suggest that the abundant spontaneous Ca2+ activity in astrocytes in the ischemic penumbra of old mice may be a novel target for neuroprotection strategies. A video abstract of this article can be found at https://youtu.be/AKlwKFsz1qE .  相似文献   
34.
35.
Genes induced by a high-oxygen environment in Entamoeba histolytica   总被引:3,自引:0,他引:3  
Entamoeba histolytica, although a microaerophilic protozoan parasite, encounters a high-oxygen environment, during invasive amoebiasis. The parasite requires specific regulation of certain proteins to maintain its physiological functions to survive in the more oxygenated condition. Our endeavor was to know how does amoeba adapt itself in a high-oxygen environment. Reactive oxygen species (ROS) was found to accumulate in an increasing concentration within the stressed trophozoites in a time-dependent manner. Increased cytopathic activity was detected at 2h in high-oxygen-exposed E. histolytica lysate compared to lysate of normal E. histolytica trophozoites by Ussing chamber assay. The differential display and semi-quantitative polymerase chain reaction showed overexpression in the mRNA levels of thiol-dependent peroxidase (Eh29), superoxide dismutase (SOD), EhCP5, G protein, HSP70, and peptidylprolyl isomerase at different time periods of oxidative stressed trophozoites compared to normally cultured E. histolytica. Analyses of the up-regulated genes that are associated with stress response, viz., signal transduction, tissue destruction, and oxidative stress management, including enhanced expression of a 29-kDa Eh29, suggest that this organism has several protective mechanisms to deal with oxidative stress during invasion.  相似文献   
36.
Enterotoxigenic Escherichia coli (ETEC) produces a variety of colonization factors necessary for attachment to the host cell, among which CS6 is one of the most prevalent in ETEC isolates from developing countries. The CS6 operon is composed of 4 genes, cssA, cssB, cssC, and cssD. The molecular mechanism of CS6 assembly and cell surface presentation, and the contribution of each protein to the attachment of the bacterium to intestinal cells remain unclear. In the present study, a series of css gene-deletion mutants of the CS6 operon were constructed in the ETEC genetic background, and their effect on adhesion to host cells and CS6 assembly was studied. Each subunit deletion resulted in a reduction in the adhesion to intestinal cells to the same level of laboratory E. coli strains, and this effect was restored by complementary plasmids, suggesting that the 4 proteins are necessary for CS6 expression. Bacterial cell fractionation and western blotting of the mutant strains suggested that the formation of a CssA-CssB-CssC complex is necessary for recognition by CssD and transport of CssA-CssB to the outer membrane as a colonization factor.  相似文献   
37.
A cost-effective melamine-based polyaminal covalent polymer (CPCMERI-2) has been prepared by a facile synthetic approach using the solvothermal condensation reaction and characterized by solid-state analytical tools like 13C NMR, PXRD, N2 sorption isotherm and FT-IR. The electron-rich moieties in the skeletal backbone induce hydrophobicity in the polymer with an appreciable water contact angle of 130°. AFM study establishes the plausible reason for the hydrophobicity. On account of its high thermal and chemical stability, the polymer CPCMERI-2 has been projected as a next-generation sorbent material for oil-like materials, and executed liquid-phase adsorption of kerosene over water surface. CPCMERI-2 selectively adsorbs kerosene and has a feeble adsorption affinity towards diesel and some other organic solvents like chloroform, benzene, nitrobenzene, and toluene. To improve the bio-compatibility and cost effectiveness of the material, a bio-waste material like the peel of Citrus limetta is used in the composite material, and it unveils a new avenue towards exploring the use of naturally abundant bio-material peels as low-cost sorbent materials. Additionally, CPCMERI-2 has gained attention due to its enormous potential in wastewater purification, which has also been tested in a lab-scale experimental setup. We expect that this material (CPCMERI-2) will harbinger a new type of composite polymer, wherein naturally abundant waste bio-materials could be used as precursors to explore its usefulness as an adsorbent for the removal of oils and organic pollutants.

Design and development of melamine based polyaminal covalent polymer (CPCMERI-2) for selective adsorption of organic pollutants over water surface: an initiative towards waste water purification.  相似文献   
38.

BACKGROUND:

Reconstruction of extensive lower lip defects is difficult. The authors describe a new technique of one-stage total lower lip reconstruction, with the ultimate goal being achievement of the delicate balance between adequate mouth opening and competent mouth closure, with satisfactory aesthetic outcome.

METHODS:

The authors applied their new reconstructive technique in a patient with extensive lower lip defect following excision of squamous cell carcinoma. Bilateral inferiorly based nasolabial flaps were used for reconstruction of lower lip. For vermillion reconstruction, a bucket-handle mucomuscular flap from upper lip was designed primarily using the pars marginalis portion of orbicularis oris. Compared with previously described techniques, this procedure is unique with respect to the alignment of the nasolabial flaps in relation to one another. Furthermore, this technique of vermillion reconstruction is a one-stage procedure with minimal morbidity, enables preservation of the vascular pedicle and innervation and maintains the orientation of orbicularis oris, thus providing a competent oral sphincter. To the authors’ knowledge, this mucomuscular upper lip flap has not been described earlier and has definite advantages over the commonly used methods of vermillion reconstruction.

RESULTS:

The functional and aesthetic outcomes are satisfactory on follow-up, with normal lip movements and sensation, adequate mouth opening and oral competence, good colour and texture match with adjacent tissues, and excellent volume and quality of the vermillion. No subsequent corrective surgery is required.

CONCLUSIONS:

This technique is simple and achieves the main goals of total lower lip reconstruction in a single stage with minimal morbidity.  相似文献   
39.
The anticancer effect of black tea (BT) and its polyphenols theaflavin (TF) and thearubigin (TR) has been evaluated on U-937 cell line, a myeloid leukemic cell line and on leukemic cells isolated from peripheral blood of chronic myeloid leukemia (CML) patients. In both types of cells, cell growth inhibition was observed 24 hrs after treatment with BT, TF and TR. MTT assay showed growth inhibition of metabolically active cells and inhibition of DNA synthesis was observed by 3H-Thymidine incorporation after treatment with the compounds. In all cases TF and TR were more effective than BT, suggesting that these are possibly the active components in BT responsible for its antileukemic activity. Superoxide dismutase (SOD), a free radical scavenger, was found to be increased by TF, whereas BT and TR lowered the level in comparison to the control. The present study is the first report of antileukemic effect of BT and its polyphenols.  相似文献   
40.
Two new boron compoumds, dihydroxy(oxybiguanido) boron (iii) hydrochloride monohydrate (HB) and guanidine biboric acid adduct (GB) were used in this study to observe the antitumor effect. Leukemic blast cells isolated from chronic myeloid leukemia (CML) patients showed significant cell growth inhibition within twentyfour hours. IC50 of GB and HB was 2mg/ml. The metabolically active cells were found to be inhibited by drug treatment as assessed by MTT test. Inhibition of 3H Thymidine incorporation also supported the above result. In this study we investigated the molecular mechanisms by which HB and GB induce apoptosis in immature blast cells.  相似文献   
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