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21.
25 cases of thalassaemia major were studied by 2D and M-mode echocardiography. A significantly increased (p less than 0.001) mean value (100.8 +/- 27.37 msec, range 80 to 140 msec) of A2-E (early relaxation period) interval on M-mode was observed in thalassemia in comparison to mean level (82.6 +/- 5.7, range 60 to 100 msec) of control population. No significant differences were noted in FS % (fractional shortening) and EF% (ejection fraction) when compared to corresponding normal values respectively. Mean serum iron concentration (142.2 +/- 29.1 micrograms/dl, range 102 to 192 micrograms/dl) was significantly higher in thalassaemia as compared to normal population (mean 106.3 +/- 11.4 micrograms/dl, range 75 to 120 micrograms/dl). There was also a direct correlation between serum iron concentration and A2-E interval. 11 patients (44%) showed abnormal A2-E interval but only 3 patients (12%) showed abnormal percentage of FS and EF. It is therefore concluded that A2-E interval will help to detect early left ventricular dysfunction much before overt and irreversible heart failure becomes manifest and which will also help to optimise transfusion and chelation therapy.  相似文献   
22.
The hepatitis B vaccine is considered to be highly immunogenic and has a good safety profile. In adults, it has a primary non-response rate of 5%-10%. Causes of nonresponse to hepatitis B vaccine include age, sex, obesity smoking. Certain human leucocyte antigen (HLA) phenotypes have been known to be associated with responsiveness to the vaccine, and found to be different in different ethnic groups, such as Caucasians and Orientals. The study was designed to identify the HLA phenotypes that are associated with non-responsiveness to hepatitis B virus (HBV) vaccination amongst a cohort of Indian subjects who agreed to participate in the vaccination programme. The study was offered to 107 volunteers, of whom 102 were found to be negative for HBV markers (hepatitis B surface antigen [HBsAg], anti-HBc, anti-HBe, anti-HBs, hepatitis Be antigen [HBeAg]) . All 102 volunteers were offered recombinant hepatitis B vaccine (20 microg) at 0, 1, and 6 months. Anti-HBs antibody titres were tested on days 90 and 210 of the first vaccine dose. HLA typing was done using standard microlymphotoxicity tests. The seroconversion rate of the hepatitis B vaccine was 86.3% (88/102). Fifteen nonresponders (15/102) and 15 of the 88 responders were randomly selected after age and sex matching for the purpose of studying the HLA phenotypes. HLA subtypes A1, B15, B40, A10 and DQ2 were found to be increased among nonresponders while HLA- A11, C3, DR10, DR51 (p>0.05) were the most common phenotypes amongst the responders. Further studies are needed to characterize the HLA phenotypes amongst the responders in different ethnic groups in India with respect to HBV vaccination.  相似文献   
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The present study was undertaken to investigate the food–drug interaction of carbamazepine (CBZ). Common fruit juices [grapefruit juice (GFJ), lime juice (LJ)], known to inhibit the enzyme cytochrome P450 3A4 (CYP3A4), and some widely consumed beverages [milk (M), black tea (BT)] were involved in this study in the presence of CBZ, as might happen during clinical therapy. The effects of the beverages on the pharmacokinetics and drug-induced toxicity of CBZ was observed after concomitant administration for a period of 28 days. Accordingly, the influence of altered bioavailability of CBZ on its antiepileptic activity was investigated. A significant shift in the Cmax as well as Tmax of CBZ was observed in the presence of LJ and GFJ. This increase in bioavailability significantly enhanced hepatotoxicity and delayed the onset of tremor and piloerection against pentylene tetrazole (PTZ)-induced seizure in experimental animals. However, increased toxicity of CBZ was found to be absent with BT. Thus, from our observation, LJ or GFJ in the presence of CBZ significantly increased the bioavailability of CBZ, which might lead to increased toxicity and antiepileptic activity of the drug.  相似文献   
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Response     
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A 62‐year‐old male presented to his treating cardiologist for routine interrogation of his implantable cardiac defibrillator on the background of severe ischemic cardiomyopathy and end‐stage kidney disease on hemodialysis. The device log revealed multiple paroxysms of atrial fibrillation; however, upon scrutinizing these episodes it was evident that they always corresponded to episodes of hemodialysis while dialyzing through a chronic dialysis catheter, but not while dialyzing via an arteriovenous fistula. We report the novel finding of inappropriate sensing of current leak from the catheter by a lead with a floating atrial dipole.  相似文献   
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The development of concise methods for the synthesis of small functionalised spirocyclic molecules is important in the search of new bioactive molecules. To contribute this, here we represent a diastereoselective oxa-hetero-Diels–Alder reaction for the synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives and studied their in vitro anticancer activities. Using previously less explored cyclic ketone i.e. indane-1,3-dione and 3-vinyl-2H-chromene derivatives, we obtained novel spiro-heterocyclic frameworks at the interphase between “drug-like” molecules and natural products. Various spiro indanone fused pyrano[3,2-c]chromene derivatives were synthesized regiospecifically bearing a quaternary stereocenter in high yields (up to 85%) with excellent diastereoselectivity in toluene using 4 Å MS as additive under reflux condition at 120 °C. In vitro cytotoxic studies of these compounds against MCF-7 (breast cancer), HCT-116 (colon cancer), H-357 (oral cancer), MD-MB-231(Breast cancer) cell lines were evaluated by MTT {3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide} assay in vitro. The screening results revealed that many of the compounds are showing moderate to high levels of anticancer activities against the tested cancer cell lines and some displayed potent inhibitory activities in comparison to the commercial anticancer drug 5-fluorouracil (5-FU). Among the series, compound 3′c showed most potent cytotoxicity (15.0–27.5 μM) in three cancer cell lines (MCF-7, HCT-116 and MD-MB-231).

Synthesis of novel spiro indanone fused pyrano[3,2-c]chromene derivatives following hetero-Diels–Alder reaction has been demonstrated and evaluated for their in vitro anticancer activity.  相似文献   
29.
Hydrogels are becoming widely used in biomaterial applications. The available methods for the preparation of these materials are continually growing. The gelation time (GT) of silk protein fibroin is difficult to control by physical methods. The cross-linkers used in available chemical techniques are likely to impact the biocompatibility of the resultant materials. In this paper, we demonstrate that the addition of sodium N-lauroyl sarcosinate (an amino-acid-based surfactant) accelerates the formation of hydrogels from fibroin. GT, turbidity variations, changes of viscoelasticity during the gelation process, and the mechanical properties of the products are measured. The secondary structure was probed by Fourier transform infrared spectroscopy, X-ray diffraction and the morphologies of the products were investigated by scanning electron microscopy. Transformations in the β-sheet content were monitored by the fluorescence of Thioflavine T and circular dichroism measurements. The relationship between the surface tension of sodium N-lauroyl sarcosinate and the GT was also explained. To investigate cell compatibility, fibroblast cells were seeded onto the surface of the hydrogels. The results indicate that the sodium N-lauroyl sarcosinate/fibroin GT can be controlled. This blend-hydrogel demonstrates excellent cell compatibility, good compression strength, and outstanding compression-recovery characteristics. Sodium N-lauroyl sarcosinate/silk fibroin hydrogels containing β-sheets have considerable potential as replacement materials in addressing the tissue defects involved with repair surgery.  相似文献   
30.
Aim: Localization of isolated clusters of anterior olfactory nucleus (AON) in a human olfactory bulb and tract. Materials and methods: This investigation was done on human olfactory bulbs and their tracts, collected from the freshly donated cadavers, before embalming, in the Department of Anatomy, IPGMER, Kolkata. H&E stained histological slides were prepared along the whole length of specimens and examined under a Leica DM 2000 microscope and with a Leica Quin image analyzer. Results: The anterior olfactory nucleus was detected in the form of a major cluster and in two smaller clusters of neurons. The major cluster was located at the caudal pole of the bulb and was composed of medium-sized triangular cells which had an average diameter of 13.92 ± 3.43 μm. Out of the two minor clusters, one was detected at the beginning and another at the middle of the olfactory tract. Here neurons were little larger in size and their diameter ranged approximately 15–17 μm. Olfactory striae also accommodated some neurons in a scattered manner. Conclusion: This observation will be helpful in exploration of the complex role of AON in the organization and function of the olfactory system and its clinical significance in human.  相似文献   
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