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71.
Development of efficient and safe nucleic acid carriers (vectors) is one of the essential requirements for the success of gene therapy. Here, we have evaluated the gene transfer capability of chitosan-PEI (CP) conjugates prepared by conjugating low molecular weight branched polyethylenimine (LMWP) with depolymerized chitosans (7 and 10 kDa) via their terminal aldehyde/keto groups. The CP conjugates interacted efficiently with nucleic acids and also showed higher cellular uptake. These conjugates on complexation with DNA yielded nanoparticles in the size range of 100-130 nm (in case of C7P) and 115-160 nm (in case of C10P), which exhibited significantly higher transfection efficiency (~2-42 folds) in vitro compared to chitosans (high and low mol. wt.) and the commercially available transfection reagents retaining cell viability almost comparable to the native chitosan. Of the two CP conjugates, chitosan 7 kDa-LMWP (C7P) displayed higher gene transfer ability in the presence and absence of serum. Luciferase reporter gene analysis in male Balb/c mice receiving intravenous administration of C7P3/DNA polyplex showed the maximum expression in their spleen. Further, tuftsin, a known macrophage targeting molecule, was tethered to C7P3 and the resulting complex, i.e., C7P3-T/DNA, exhibited significantly higher gene expression in cultured mouse peritoneal macrophages as compared to unmodified C7P3/DNA complex without any cytotoxicity demonstrating the suitability of the conjugate for targeted applications. Conclusively, the study demonstrates the potential of the projected conjugates for gene delivery for wider biomedical applications. 相似文献
72.
Mesenchymal stem cells: molecular targets for tissue engineering 总被引:10,自引:0,他引:10
73.
Trivendra Tripathi Mohammad Shahid Adil Raza Haris M. Khan Rahat Ali Khan Abbas Ali Mahdi Mashiatullah Siddiqui Abida Malik Aijaz Ahmed Khan 《Experimental and toxicologic pathology》2012,64(7-8):875-881
ObjectiveThe present study was designed to delineate the hepatotoxicological roles of histamine dose-dependently in immunized rabbits.MethodsThe cohort comprised of three groups (II, III and IV), containing 18 rabbits each, and received subcutaneous histamine 50 μg/kg, 100 μg/kg and 200 μg/kg, respectively for 10 days (b.i.d., starting from 3 days prior to immunization until 7 days after immunization). Group I (control, n = 18) received subcutaneous sterile distilled water for 10 days. They were subsequently immunized at day 3 with intravenous injection of SRBC (1 × 109 cells/ml). Blood samples were collected on pre-immunization (pre-I) day 0, as well as on days 7-, 14-, 21-, 28- and 58-post-immunization (post-I). Biochemical parameters aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and bilirubin [total bilirubin (TB), direct bilirubin (DB) and indirect bilirubin (IB)] were determined.ResultsGroups II and IV revealed a significant decrease (on day 0-pre-I) and a significant increase (on days 7-, 14-, 21-, 28- and 58-post-I) in ALT and AST levels, when compared with the corresponding values of groups I and III while group II showed a significant increase in ALT and AST levels as compared to group IV. ALP levels in groups II, III and IV showed a significant enhancement when compared with group I. Moreover, results of TB, DB and IB demonstrated increased levels in group III when compared with groups I, II and IV. The results were found statistically significant (p < 0.05).ConclusionShort-term treatment of histamine produces dose-dependent differential patterns of hepatic dysfunctions suggestive mild liver degeneration warranting further long-term studies. 相似文献
74.
This paper traces the role of alcohol production and use in the daily lives of people in India, from ancient times to the present day. Alcohol use has been an issue of great ambivalence throughout the rich and long history of the Indian subcontinent. The behaviors and attitudes about alcohol use in India are very complex, contradictory and convoluted because of the many different influences in that history. The evolution of alcohol use patterns in India can be divided into four broad historical periods (time of written records), beginning with the Vedic era (ca. 1500–700 BCE). From 700 BCE to 1100 CE, (“Reinterpretation and Synthesis”) is the time of emergence of Buddhism and Jainism, with some new anti-alcohol doctrines, as well as post-Vedic developments in the Hindu traditions and scholarly writing. The writings of the renowned medical practitioners, Charaka and Susruta, added new lines of thought, including arguments for “moderate alcohol use.” The Period of Islamic Influence (1100–1800 CE), including the Mughal era from the 1520s to 1800, exhibited a complex interplay of widespread alcohol use, competing with the clear Quranic opposition to alcohol consumption. The fourth period (1800 to the present) includes the deep influence of British colonial rule and the recent half century of Indian independence, beginning in 1947. The contradictions and ambiguities—with widespread alcohol use in some sectors of society, including the high status caste of warriors/rulers (Kshatriyas), versus prohibitions and condemnation of alcohol use, especially for the Brahmin (scholar-priest) caste, have produced alcohol use patterns that include frequent high-risk, heavy and hazardous drinking. The recent increases in alcohol consumption in many sectors of the general Indian population, coupled with the strong evidence of the role of alcohol in the spread of HIV/STI infections and other health risks, point to the need for detailed understanding of the complex cross-currents emerging from the past history of alcohol use and abuse in India. 相似文献
75.
Our laboratory focuses on the study of the molecular regulation of T lymphocyte homeostasis, particularly as it relates to immunological tolerance, apoptosis, and autoimmune diseases. Through intense molecular research on the regulation of lymphocyte fate, the Fas receptor and other tumor necrosis factor receptors as well as their ligands have emerged as key regulators of T lymphocyte apoptosis. We are studying genetic abnormalities of this death pathway, particularly in the context of autoimmune lymphoproliferative syndrome (ALPS) and other non-ALPS conditions affecting lymphocyte homeostasis. These studies have led to further investigations of the regulation of the NF-kappaB signaling pathway, the molecular basis for programed cell death and viral cytopathicity, mechanisms of autoimmunity, and the regulation of mature T-cell tolerance. Our investigations promise to provide insight into the molecular mechanisms behind the regulation of immune response and contribute to the development of novel diagnostic and treatment methods for autoimmune diseases. 相似文献
76.
Objectives
The purpose of the study was to compare the efficacy of misoprostol 400 μg per rectally, injection oxytocin 10 IU intramuscular, injection methylergometrine 0.2 mg intravenously and injection (0.5 mg ergometrine + 5 IU oxytocin) intramuscular on reducing blood loss in third stage of labor, duration of third stage of labor, effect on haemoglobin of the patient, need of additional oxytocics or blood transfusion and associated side effects and complications.Study Design
A prospective non-randomized uncontrolled study was carried out in the Department of Obstetrics and Gynecology, SSG Hospital and Medical College, Baroda enrolling 200 women and dividing them into four groups. Active management of 3rd stage of labor was done using one of the 4 uterotonics as per the group of the patient. The main outcome measures were the amount of blood loss, the incidence of postpartum hemorrhage and a drop in hemoglobin concentration from before delivery to 24 h after delivery.Results
Methylergometrine was found to be superior to rest of the drugs in the study with lowest duration of third stage of labor (P = 0.000096), lowest amount of blood loss (P = 0.000017) and lowest incidence of PPH (P = 0.03). There was no significant difference in the pre-delivery and the post-delivery hemoglobin concentration amongst the four groups with P = 0.061. The need of additional oxytocics and blood transfusion was highest with misoprostol as compared to all other drugs used in the study with P = 0.037 and 0.009, respectively. As regards side effects, misoprostol was associated with shivering and pyrexia in significantly high number of patients as compared to the other drugs used in the study while nausea, vomiting and headache were more associated with methylergometrine and ergometrine–oxytocin. However all the side effects were acceptable and preferable to the excessive blood loss.Conclusion
Methylergometrine has the best uterotonic drug profile amongst the drugs used, strongly favouring its routine use as oxytocic for active management of third stage of labor. Misoprostol was found to cause a higher blood loss compared to other drugs and hence should be used only in low resource setting where other drugs are not available. The role of misoprostol in third stage of labor needs larger studies to be proved. 相似文献77.
Arpita De Aruna Nigam Abhinav Jain Neha Gupta Reva Tripathi 《Journal of minimally invasive gynecology》2019,26(5):981-985
Uterine inversions are a rare entity, and most occur in the postpartum period. Nonpuerperal inversion accounts for only 16% of cases and are mostly associated with a submucous myoma. A 38-year-old woman with a submucous myoma presented with severe lower abdominal pain, acute retention of urine, and hypotension. Because the clinical examination was inconclusive due to severe pain and the ultrasound was dubious, diagnosis was made with magnetic resonance imaging. Successful laparoscopic hysterectomy was contemplated after correcting uterine inversion. This case highlights the diagnostic dilemmas and the key points during laparoscopic management of uterine inversion. 相似文献
78.
Isolation of a lytic bacteriophage against virulent Aeromonas hydrophila from an organized equine farm 下载免费PDF全文
79.
80.
Ruchi Roy Sunil K. Singh Mukul Das Anurag Tripathi Premendra D. Dwivedi 《Immunology》2014,142(3):453-464
Macrophages are among the most sensitive immune cells because of their phagocytic activity and are prone to become dysfunctional or not able to perform properly if nanoparticle load increases. We have previously reported that zinc oxide nanoparticles (ZNPs) induce inflammatory responses in macrophages that contribute to their death. Recognition of ZNPs by pattern recognition receptors such as toll‐like receptors (TLRs) might be a factor in the initiation of these responses in macrophages. Therefore, in this study we explored the role played by TLR6 and mitogen‐activated protein kinase (MAPKs) pathways in the inflammatory responses of macrophages during ZNPs exposure. ZNPs‐activated macrophages showed enhanced expression of activation and maturation markers (CD1d, MHC‐II, CD86 and CD71). Among various TLRs screened, TLR6 emerged as the most potent activator for ZNPs‐induced inflammatory responses. Downstream signalling proteins myeloid differentiation 88, interleukin‐1 receptor associated kinase and tumour necrosis factor receptor‐associated factor were also enhanced. On inhibiting MAPKs pathways individually, the inflammatory responses such as interleukin‐1β, interleukin‐6, tumour necrosis factor‐α, cyclooxygenase‐2 and inducible nitric oxide synthase were suppressed. TLR6 silencing significantly inhibited the pro‐inflammatory cytokine levels, reactive nitrogen species generation and inducible nitric oxide synthase expression. Also, inhibition of MAPKs in the absence of TLR6 signalling validated the link between TLR6 and MAPKs in ZNPs‐induced inflammatory responses. TLR6 was found to be co‐localized with autophagosomes. Macrophages lacking TLR6 inhibited the autophagosome marker protein‐microtubule‐associated protein1 light chain 3‐isoform II formation and phagocytosis. These results demonstrate that inflammatory responses caused by ZNPs‐activated macrophages strongly depend on TLR6‐mediated MAPK signalling. 相似文献