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1.
Anuj Shrestha Zeeshan Jawa Kathryn L. Koch Amy B. Rankin Qun Xiang Anand Padmanabhan Matthew S. Karafin Joshua J. Field 《Journal of clinical apheresis》2015,30(6):353-358
Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
2.
The antitumor effects of two polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG), when combined with cis-diamminedichlroplatinum (CDDP) or mitomycin C (MMC), were studied using human gastric cancer cells xenotransplanted into nude mice. DFMO 1000 mg/kg and MGBG 50 mg/kg were given intraperitoneally for 6 successive days, while CDDP 3 mg/kg or MMC 2 mg/kg was given every second day. Although DFMO and MGBG plus MMC did suppress the tumor growth, the combination with CDDP led to no suppression, and rapid growth occurred after the cessation of therapy. The inhibition of tumoral DNA biosynthesis and a decline in polyamine levels, were also not observed. The polyamine antimetabolites when used with CDDP did not produce the desired antitumor efficacy, even though the platinum concentration in the tumor tissue was high. On the contrary, however, DFMO and MGBG when combined with MMC did suppress tumor growth, inhibited DNA biosynthesis, and tissue polyamine levels were low. These results suggest that though CDDP and MMC belong to a similar category of DNA attacking, bifunctional alkylating agents, the findings of these two drugs are contradictory. Here, the mechanism of action no doubt plays a contributory role. 相似文献
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S Fujimoto R D Shrestha M Kokubun K Kobayashi S Kiuchi C Konno K Okui 《Nihon Geka Gakkai zasshi》1990,91(2):201-205
Six patients with peritoneal recurrence after radical operation for gastric cancer were treated by an intraperitoneal hyperthermic perfusion (IPHP) combined with surgery (IPHP group). Immediately after surgery, a 2-hour IPHP was performed, using a perfusate containing 10 micrograms/ml of MMC, warmed at the inflow temperature of 46.5 +/- 1.1 degree C. Within the same period of time, 5 patients with intra-abdominal recurrent gastric cancer (control group) were treated by an intraperitoneal administration of MMC 10 mg combined with surgery. These 11 patients had malignant peritoneal effusion and, although in 3 of the control group, ascitic effusion did re-accumulate rapidly soon after surgery, the 6 patients of IPHP group did not re-accumulate post-hyperthermically. The average survival duration of IPHP group is 13.6 +/- 10. 6 months, whereas that for controls is 3.0 +/- 2.1 months. Again, the survival rate for IPHP group surpassed that for controls at p = 0.012 and p = 0.008, in a generalized Wilcoxon method and Logrank method, respectively. Post-hyperthermically, hypoproteinemia and thrombocytopenia occurred transitorily. These results show that IPHP using MMC combined with surgery is a safe, reliable treatment for patients with peritoneal recurrence due to gastric cancer. 相似文献
5.
The use of cardenolide-containing Moraceae in the dart poisons of South America is reviewed. Those prepared by the Chocó Indians of western Colombia--called niaará or kieratchi--have probably been made from the latex of Naucleopsis amara and N. glabra. In Ecuador, the Colorado Indians used N. chiguila, while the Coaiquer Indians still derive a poison from the latex of N. naga and the Cayapá Indians occasionally make use of a blowgun poison, hambi, which probably also comes from a Naucleopsis species. The Kaborí (Rio Uneiuxi Makú) Indians of north-western Brazil may have utilized Maquira coriacea, but a more recent collection documents N. mello-barretoi latex as a source of their poison. The Tikuna Indians of western Brazil included leaves and bark of N. stipularis in one of their poisons. The principal cardiac glycosides present in Maquira species are strophanthidin-based and the main ones occurring in Naucleopsis species are antiarigenin- as well as strophanthidin-based. The structures of two new glycosides, isolated from dart-poison samples, have been established as strophanthidin beta-D-glucomethylosido-D-alloside and beta-D-digitoxosido-D-alloside. The former is a major component of pakurin, the crystalline glycoside mixture prepared by Santesson in 1928 from a Chocó Indian poison. 相似文献
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High prevalence of hepatitis B virus pre-s mutant in countries where it is endemic and its relationship with genotype and chronicity 总被引:7,自引:0,他引:7
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Huy TT Ushijima H Win KM Luengrojanakul P Shrestha PK Zhong ZH Smirnov AV Taltavull TC Sata T Abe K 《Journal of clinical microbiology》2003,41(12):5449-5455
It has been reported that hepatitis B virus (HBV) mutants carrying mutations in the pre-S region can be found in infected patients. In this study, we investigated the prevalence of the HBV variant with the pre-S mutant in different geographic regions, including countries with low and high levels of endemic HBV infection, and analyzed the correlation with clinical findings. We examined 387 HBV DNA-positive serum samples from individuals among 12 countries, consisting of Vietnam, Myanmar, Thailand, China, Korea, Nepal, Japan, Russia, Spain, United States, Bolivia, and Ghana. HBV pre-S mutants were detected in 71 (18.3%) of 387 serum samples tested. This mutant was the most prevalent in Vietnam (36%), followed by Nepal (27.3%), Myanmar (23.3%), China (22.4%), Korea (14.3%), Thailand (10.5%), Japan (7.7%), and Ghana (4.3%). In contrast, no case with this mutation was found in Russia, Spain, United States, and Bolivia. Among the HBV deletion mutations, 15.5% (11 of 71) occurred in the pre-S1 and 46.5% (33 of 71) in the pre-S2 regions. Eight (11.3%) cases had a mutation in both the pre-S1 and pre-S2 regions. In addition, a point mutation at the pre-S2 starting codon was observed in 19 (26.7%) cases. The detection rate of the HBV mutant in patients with hepatocellular carcinoma was significantly higher than in other patients (P < 0.05). Furthermore, these mutants were found more frequently in genotype B (25%) and genotype C (24.5%) than in the other genotypes (P < 0.05). Our results indicated that there was a high prevalence of HBV pre-S mutation in regions of endemic HBV infection in Asia. Furthermore, the pre-S mutation appeared to be correlated with hepatocellular carcinoma and HBV genotypes. 相似文献
9.
The Escherichia coli O26 serogroup includes important food-borne pathogens associated with human and animal diarrheal disease. Current typing methods have revealed great genetic heterogeneity within the O26 group; the data are often inconsistent and focus only on verotoxin (VT)-positive O26 isolates. To improve current understanding of diversity within this serogroup, the genomic relatedness of VT-positive and -negative O26 strains was assessed by comparative genomic indexing. Our results clearly demonstrate that irrespective of virulence characteristics and pathotype designation, the O26 strains show greater genomic similarity to each other than to any other strain included in this study. Our data suggest that enteropathogenic and VT-expressing E. coli O26 strains represent the same clonal lineage and that VT-expressing E. coli O26 strains have gained additional virulence characteristics. Using this approach, we established the core genes which are central to the E. coli species and identified regions of variation from the E. coli K-12 chromosomal backbone. 相似文献
10.
Martagon-Villamil J Shrestha N Sholtis M Isada CM Hall GS Bryne T Lodge BA Reller LB Procop GW 《Journal of clinical microbiology》2003,41(3):1295-1298
We designed and tested a real-time LightCycler PCR assay for Histoplasma capsulatum that correctly identified the 34 H. capsulatum isolates in a battery of 107 fungal isolates tested and also detected H. capsulatum in clinical specimens from three patients that were culture positive for this organism. 相似文献