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91.
Radiofrequency ablation is the treatment of choice for patients with Wolff-Parkinson-White syndrome and symptomatic tachyarrhythmias. The technique involves localising the pathway with multiple catheters at various sites followed by radiofrequency energy application at that site. Single catheter approach has been described for ablation of manifest left-sided accessory pathways. In this article, we report the ablation of accessory pathways in different locations in patients with Wolff-Parkinson-White syndrome by using a two-catheter approach. Twenty-three consecutive patients with symptomatic Wolff-Parkinson-White syndrome were taken up for radiofrequency ablation with this approach. Pathways could be successfully ablated in 11 out of 13 patients with left free wall, 5 out of 7 with right posteroseptal, one patient of left posteroseptal and each of the 2 patients of right mid septal locations giving an overall success in 19/23 (82.6%) patients. Hence, two-catheter approach can be used safely to ablate accessory pathways in different locations with high success rate, thus minimising the procedure time associated with conventional approach. 相似文献
92.
Methotrexate (MTX) is among the best-tolerated disease-modifying antirheumatic drugs for the treatment of rheumatoid arthritis (RA); major drawbacks of MTX therapy are the large interpatient variability in clinical response and the unpredictable appearance of a large spectrum of side effects. Several studies have demonstrated gene polymorphism that may regulate intracellular methotrexate metabolic pathway enzymes linked to drug efficacy and safety, but the evidence available is not yet conclusive. We decided to run a pilot study to determine the incidence of Methylene tetrahydrofolate (MTHFR; C677T, A1298C) and Thymidylate synthase (TS; 5′ UTR repeat, 3′ UTR deletion) gene polymorphism in rheumatoid arthritis patients in our community (Indian Asian) and further explore its association with MTX response (efficacy, toxicity). Thirty-four naïve RA patients on supervised MTX therapy and 139 healthy controls were genotyped for A1298C and C677T polymorphism of the MTHFR gene and 5′ UTR repeat and 3′ UTR deletion polymorphism of the TYMS gene by polymerase chain reaction-restriction fragment length polymorphism. Association, if any, between gene polymorphism and MTX response in RA patients was analyzed. The MTHFR A1298C ‘C’ allele incidence among RA patients (46%) was significantly higher (χ 2?=?4.24, P?0.05, OR?=?1.68). None of the other allele tested showed any association. Although a small sample study, our findings do not suggest a significant association of MTHFR/TS allele/genotype with MTX response in our ethnically distinct Indian (Asian) RA patients. 相似文献
93.
BACKGROUND: An attempt was made to induce aortoarteritis in mice by using various antigens. METHODS AND RESULTS: The Swiss mice were immunized with eight different antigens and were grouped A to G. Group H served as control. The mice were then bled at 1st, 2nd, 4th, 6th and 8th month interval post-immunization for estimating antibody titer. Then the mice were sacrificed and the heart, aorta and kidney were taken out and processed for hematoxylin-eosin staining. There was gradual increase in the antibody titer from 1st month till 4th month within all the experimental groups (A-G), when compared with control group H. The titer started falling sharply from 6th month post-immunization. However, the control group H did not show much variation. When each individual group was compared separately with control group H, the significant statistical value was obtained. Histopathological examination revealed mild inflammation (+) in kidney by 2nd month, moderate inflammation (++) by 6th month, extensive inflammation (+++) by 8th month and alteration in the normal parenchyma of kidney by 8th month. CONCLUSIONS: The histopathological changes brought out through antigens were more pronounced by 8th month following injection of tunica media, tunica adventitia, tunica intima and aorta collagen as compared to that of standard collagen and mouse aorta injections. 相似文献
94.
Primary hepatocellular carcinoma in idiopathic hemochromatosis after reversal of cirrhosis 总被引:1,自引:0,他引:1
R S Blumberg S Chopra R Ibrahim J Crawford F A Farraye J B Zeldis M D Berman 《Gastroenterology》1988,95(5):1399-1402
Previous reports have emphasized the association of primary hepatocellular carcinoma in patients with idiopathic hemochromatosis with cirrhosis. In contrast, patients with idiopathic hemochromatosis without cirrhosis have no increased risk of hepatocellular carcinoma. Phlebotomy therapy, by preventing the accumulation of parenchymal iron and subsequent cirrhosis, is believed to prevent hepatocellular carcinoma in the precirrhotic stage of the disease. We report the case of a 67-yr-old man with a 32-yr history of idiopathic hemochromatosis complicated by cirrhosis, who had reversal of cirrhosis with phlebotomy therapy, yet developed hepatocellular carcinoma. There was no serologic or tissue evidence of hepatitis B infection. 相似文献
95.
Dinesh K. Bhargava M.D. PhD. Shriniwas M.D. Prem Chopra M.D. Sandeep Nijhawan D.M. S. Dasarathy D.M. Anil K. S. Kushwaha Ph.D. 《The American journal of gastroenterology》1992,87(1):109-112
We report laparoscopic findings in 38 proven cases of peritoneal tuberculosis. The laparoscopic appearances can be classified into three types: thickened peritoneum with miliary yellowish white tubercles with or without adhesions (n = 25), only thickened peritoneum with or without adhesions (n = 8), and fibroadhesive pattern (n = 5). Biopsies were avoided from fibroadhesive lesions due to risk of complications. Visual diagnosis was accurate in 95% of patients. In comparison, in 27 (82%) of 33 patients, the examination enabled a histologic diagnosis to he made on the basis of typical granulomas. The combined use of guinea pig inoculation and culture isolated Mycobacterium tuberculosis in six (37.5%) of 16 patients. Mycobacteria were scarcely (3%) seen on histological sections. We conclude that, although target biopsy is an effective method of obtaining an early diagnosis of peritoneal tuberculosis, chemotherapy may be started on the basis of visual laparoscopic appearances alone. 相似文献
96.
97.
Ulrike Schliesser Martin Chopra Andreas Beilhack Christine Appelt Simone Vogel Julia Schumann Ivo Panov Katrin Vogt Stephan Schlickeiser Sven Olek Kathryn Wood Christine Brandt Hans‐Dieter Volk Birgit Sawitzki 《European journal of immunology》2013,43(12):3291-3305
The transfer of alloreactive regulatory T (aTreg) cells into transplant recipients represents an attractive treatment option to improve long‐term graft acceptance. We recently described a protocol for the generation of aTreg cells in mice using a nondepleting anti‐CD4 antibody (aCD4). Here, we investigated whether adding TGF‐β and retinoic acid (RA) or rapamycin (Rapa) can further improve aTreg‐cell generation and function. Murine CD4+ T cells were cultured with allogeneic B cells in the presence of aCD4 alone, aCD4+TGF‐β+RA or aCD4+Rapa. Addition of TGF‐β+RA or Rapa resulted in an increase of CD25+Foxp3+‐expressing T cells. Expression of CD40L and production of IFN‐γ and IL‐17 was abolished in aCD4+TGF‐β+RA aTreg cells. Additionally, aCD4+TGF‐β+RA aTreg cells showed the highest level of Helios and Neuropilin‐1 co‐expression. Although CD25+Foxp3+ cells from all culture conditions displayed complete demethylation of the Treg‐specific demethylated region, aCD4+TGF‐β+RA Treg cells showed the most stable Foxp3 expression upon restimulation. Consequently, aCD4+TGF‐β+RA aTreg cells suppressed effector T‐cell differentiation more effectively in comparison to aTreg cells harvested from all other cultures, and furthermore inhibited acute graft versus host disease and especially skin transplant rejection. Thus, addition of TGF‐β+RA seems to be superior over Rapa in stabilising the phenotype and functional capacity of aTreg cells. 相似文献
98.
Sahil Sood Lavanya Gurram Dheera Aravindakshan John Paul Supriya Chopra Jamema Swamidas Akshay Patil Umesh Mahantshetty 《Brachytherapy》2021,20(3):550-556
PurposeThe study is an audit of reporting dose and volume specifications as per the ICRU 58 for MUPIT-based interstitial brachytherapy in gynecological cancers. Correlation between total reference air kerma (TRAK) and isodose surface was also evaluated to understand the intensity of treatment in interstitial brachytherapy.Methods and MaterialsForty-two patients underwent HDR MUPIT-based interstitial brachytherapy 20 Gy in five fractions after EBRT during 2017–2019. Treated volume, high and low-dose regions, mean central dose, Dose Homogeneity Index (DHI), organ at risk doses, and TRAK values were computed.ResultsHigh-dose regions V150 mean was 12.4 cc and V200 was 4.58 cc; and low-dose region was 75.92 cc. The mean treated volume was 59.8 cc. The mean central dose was 3.7 Gy. DHI was 79%. The mean D2cm3 bladder and rectum were 2.9 Gy and 2.8 Gy. The mean TRAK was 0.16 cGy per fraction per hour at 1 m. TRAK values showed significant correlation with various isodose volumes (TRAK and V100: r = 0.943 p < 0.0005; and TRAK and V50: r = 0.953; p < 0.0005). A positive correlation was observed between TRAK and the number of needles (r = 0.746; p < 0.0005). At a median followup of 16 months, 4 of 42 patients (9.5%) had local recurrences.ConclusionsOur study shows compliance with ICRU 58 recommendations along with certain deviations. Local recurrence rate is acceptable. TRAK shows correlation with surface isodose in MUPIT-based brachytherapy and should to be evaluated in future studies. 相似文献
99.
Enhancement of neutrophil function by granulocyte-macrophage colony- stimulating factor involves recruitment of a less responsive subpopulation 总被引:3,自引:0,他引:3
Human granulocyte-macrophage colony-stimulating factor (GM-CSF) enhances numerous functions of mature neutrophils (PMN) including phagocytosis, superoxide responses to chemotaxins, antibody-dependent cellular cytotoxicity, and expression of complement receptors. A central question concerns whether the mechanism of enhancement involves quantitative increases in the response of all cells v subpopulation recruitment. The effects of GM-CSF on individual cell light scatter changes, membrane potential, and oxidant responses induced by the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (FMLP) were assessed by flow cytometry and by scoring individual cells for nitroblue tetrazolium dye (NBT) reduction. GM-CSF produced a dose- and time-dependent shift in forward light scatter that was very similar in character to that seen with FMLP or leukotriene B4 stimulation. Although not capable of depolarizing the cells directly, GM-CSF primed PMNs for enhanced membrane potential responses to FMLP by significantly increasing the proportion of depolarizing cells when compared with diluent-treated controls after a 60-minute incubation at 37 degrees C (79.4% +/- 3.4% v 29.5% +/- 4.7% GM-CSF v diluent, mean +/- SE, P less than .005, n = 11). Subpopulation recruitment by GM-CSF treatment was also demonstrated by the FMLP-elicited NBT test. Taken together, these results indicate that GM-CSF can modulate the function of mature PMN by enhancing the proportion of responsive cells. 相似文献
100.
Bash RO; Crist WM; Shuster JJ; Link MP; Amylon M; Pullen J; Carroll AJ; Buchanan GR; Smith RG; Baer R 《Blood》1993,81(8):2110-2117
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study. 相似文献