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91.
The critical role of microRNAs (miRNAs) in cell differentiation, homeostasis and cancer development has been extensively discussed in recent publications. The microRNAs with RISC enzyme complex allow it to find its complementary sequence, which is usually located in the 3′-untranslated region (UTR) of the target messenger RNA (mRNA). This is followed by inhibition of protein translation or promotion, resulting in degradation of the target gene. miR-21 has been mapped at chromosome 17q23.2, where it overlaps with the protein coding gene vacuole membrane protein 1 (VMP1), a human homologue of rat vacuole membrane protein. Recent evidence indicates that miR-21 plays a vital role in tumour cell proliferation, apoptosis and invasion. The inhibition of miR-21 may induce cell cycle arrest and increased chemosensitivity to anticancer agents, providing evidence that miR-21 functions as an oncogene in human cancer. Increased expression levels of miR-21 were observed in tumours arising from diverse tissue types. This also includes tumours of haematological origin, such as chronic lymphatic leukaemia, diffuse large B cell lymphomas (DLBCLs), acute myeloid leukaemia and Hodgkin lymphomas. Recently, it has been shown that high levels of B cell activation were induced by miR-21 in circulating B cells and are seen in HIV-infected individual. Notably, miR-21 is overexpressed in activated B cells, suggesting its assistance in maintaining B cell hyperactivation, which plays a pivotal role in HIV-infected cells. Therefore, miR-21 can be considered as a powerful biomarker in HIV-related lymphomas. The number of studies related to the role of miR-21 in HIV-related lymphomas is sparse; therefore, this mini review highlights the recent publications related to clinical impact and significance of miR-21, specifically in HIV- and non-HIV-related lymphomas.  相似文献   
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Genome-wide association studies (GWAS) have identified a genetic variant at a locus on chromosome 1p13 that is associated with reduced risk of myocardial infarction, reduced plasma levels of LDL cholesterol (LDL-C), and markedly increased expression of the gene sortilin-1 (SORT1) in liver. Sortilin is a lysosomal sorting protein that binds ligands both in the Golgi apparatus and at the plasma membrane and traffics them to the lysosome. We previously reported that increased hepatic sortilin expression in mice reduced plasma LDL-C levels. Here we show that increased hepatic sortilin not only reduced hepatic apolipoprotein B (APOB) secretion, but also increased LDL catabolism, and that both effects were dependent on intact lysosomal targeting. Loss-of-function studies demonstrated that sortilin serves as a bona fide receptor for LDL in vivo in mice. Our data are consistent with a model in which increased hepatic sortilin binds intracellular APOB-containing particles in the Golgi apparatus as well as extracellular LDL at the plasma membrane and traffics them to the lysosome for degradation. We thus provide functional evidence that genetically increased hepatic sortilin expression both reduces hepatic APOB secretion and increases LDL catabolism, providing dual mechanisms for the very strong association between increased hepatic sortilin expression and reduced plasma LDL-C levels in humans.  相似文献   
94.

Purpose

The purpose of this study is to demonstrate the role of aging\edentulousness on the maxillary arch, the size of the alveolar process, the shape and thickness of the hard palate in the South Indian dry skulls to customize more appropriate treatment of elderly edentulous patients.

Methods

One hundred dry skulls were divided into dentate and edentulous groups and were subgrouped into male and female. They were subjected to various morphological and morphometrical analyses.

Results

The data have revealed a more significant reduction in the depth and width (p?p?p?Conclusion The observed data from specific group of population may provide relevant data for their comparative analysis between different populations for a better understanding of their regional differences with respect to environmental and social influence. Moreover, the data can provide a better idea to evaluate a promising treatment strategy in prosthodontics and orthodontics in South India.  相似文献   
95.
Photodermatoses are a group of disorders resulting from abnormal cutaneous reactions to solar radiation. They include idiopathic photosensitive disorders, drug or chemical induced photosensitivity reactions, DNA repair-deficiency photodermatoses and photoaggravated dermatoses. The pathophysiology differs in these disorders but photoprotection is the most integral part of their management. Photoprotection includes wearing photoprotective clothing, applying broad spectrum sunscreens and avoiding photosensitizing drugs and chemicals.  相似文献   
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An investigation in a referral pediatric hospital has indicated that during a recent dengue outbreak in Chennai, Tamil Nadu, India, dengue in infancy constituted 20% of total dengue virus infections with low mortality rates in this hospital. In developing countries, strengthening of dengue management capabilities at hospitals can prevent dengue-related deaths in infants.  相似文献   
100.
Shigella species cause severe bacillary dysentery in humans and are associated with high morbidity and mortality. The Invasion plasmid antigen (IpaB) protein, which is conserved across all Shigella spp., induces macrophage cell death and is required to invade host cells. The present study evaluates the immunogenicity and protective efficacy of the recombinant (r) domain region of IpaB (rIpaB) of S. flexneri. rIpaB was administered either alone or was co-administered with the rGroEL (heat shock protein 60) protein from S. Typhi as an adjuvant in a mouse model of intranasal immunization. The IpaB domain region (37 kDa) of S. flexneri was amplified from an invasion plasmid, cloned, expressed in BL21 Escherichia coli cells and purified. Immunization with the rIpaB domain alone stimulated both humoral and cell-mediated immune responses. Furthermore, robust antibody (IgG, IgA) and T-cell responses were induced when the rIpaB domain was co-administered with rGroEL. Antibody isotyping revealed higher IgG1 and IgG2a antibody titers and increased interferon-gamma (IFN-γ) secretion in the co-administered group. Immunization of mice with the rIpaB domain alone protected 60%–70% of the mice from lethal infection by S. flexneri, S. boydii and S. sonnei, whereas co-administration with rGroEL increased the protective efficacy to 80%–85%. Organ burden and histopathological studies also revealed a significant reduction in lung infection in the co-immunized mice compared with mice immunized with the rIpaB domain alone. This study emphasizes that the co-administration of the rIpaB domain and rGroEL protein improves immune responses in mice and increases protective efficacy against Shigella infection. This is also the first report to evaluate the potential of the GroEL (Hsp 60) protein of S. Typhi as an adjuvant molecule, thereby overcoming the need for commercial adjuvants.  相似文献   
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