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21.
Background In recent years there has been a rapid increase in the use of proton pump inhibitors. Our institution has recently had several
shortages of IV pantoprazole, each lasting 7–10 days. The purpose of our study was to evaluate in-patient usage of IV pantoprazole.
We hypothesized that hospitalized patients with upper gastrointestinal bleeding (GIB) or risk for stress ulcers inappropriately
received IV pantoprazole based on current literature.
Methods This was a retrospective study of 165 consecutive in-patients identified as receiving pantoprazole from December 2004 to March
2005. Only patients receiving IV pantoprazole were included (n = 78). Data collected included demographics, indication and dosing of pantoprazole, admitting team (surgery vs. medicine),
and risk factors for stress ulcers.
Results Our study population had a mean age of 54 ± 17 years and 62% were male. Overall, 45% (35/78) of patients receiving IV pantoprazole
had an appropriate indication, and 19% (15/78) received the correct dose. Of the 78 patients, 43 (55%) were treated with pantoprazole
for stress ulcer prophylaxis (SUP), and 35 (45%) patients were treated for GIB. We found that none of the 43 patients treated
for SUP had an appropriate indication for pantoprazole, but all of the patients with GIB (35) had an appropriate indication.
Of the 35 patients treated for GIB with pantoprazole, only 40% (14/35) received the correct dose. In all cases of incorrect
dosing, the patients were underdosed.
Conclusions Pantoprazole is not being prescribed appropriately for stress ulcer prophylaxis in our patient population. Even in patients
appropriately receiving pantoprazole the majority were prescribed an incorrect dose. Appropriate indications and dosing of
pantoprazole could eliminate the shortages seen at our institution. 相似文献
22.
Manuel A Valenzuela Jimena Canales Alejandro H Corvalán Andrew FG Quest 《World journal of gastroenterology : WJG》2015,21(45):12742-12756
The sequence of events associated with the development of gastric cancer has been described as “the gastric precancerous cascade”. This cascade is a dynamic process that includes lesions, such as atrophic gastritis, intestinal metaplasia and dysplasia. According to this model, Helicobacter pylori (H. pylori) infection targets the normal gastric mucosa causing non-atrophic gastritis, an initiating lesion that can be cured by clearing H. pylori with antibiotics or that may then linger in the case of chronic infection and progress to atrophic gastritis. The presence of virulence factors in the infecting H. pylori drives the carcinogenesis process. Independent epidemiological and animal studies have confirmed the sequential progression of these precancerous lesions. Particularly long-term follow-up studies estimated a risk of 0.1% for atrophic gastritis/intestinal metaplasia and 6% in case of dysplasia for the long-term development of gastric cancer. With this in mind, a better understanding of the genetic and epigenetic changes associated with progression of the cascade is critical in determining the risk of gastric cancer associated with H. pylori infection. In this review, we will summarize some of the most relevant mechanisms and focus predominantly but not exclusively on the discussion of gene promoter methylation and miRNAs in this context. 相似文献
23.
24.
Renata Krupa Elzbieta Pawlowska Anna Sobczuk Katarzyna Wozniak 《Experimental and molecular pathology》2009,87(1):32-35
The RAD51 protein and its paralog, XRCC3, play an important role in the repair of DNA double-strand breaks (DSBs) by homologous recombination. Since DSBs may contribute to the pathogenesis of breast cancer and variability in DNA repair genes may be linked with some cancers, we performed a case-control study (135 cases and 175 controls) to check the association between the genotypes of the Thr241Met polymorphism of the XRCC3 gene and the 135G>C polymorphism of the RAD51 gene and breast cancer occurrence and progression. Genotypes were determined in peripheral blood lymphocytes by RFLP-PCR. We did not find any association between either polymorphism singly and breast cancer occurrence. Both polymorphisms were not related to tumor size, estrogen and progesterone receptors status, cancer type and grade. However, the Thr241Met genotype of the XRCC3 polymorphism slightly increased the risk of local metastasis in breast cancer patients (OR 2.56, 95% CI 1.27-5.17). The combined Thr241Met/135G>C genotype decreased the risk of breast cancer occurrence (OR 0.22, 95% CI 0.08-0.59). Our results suggest that the variability of the DNA homologous recombination repair genes RAD51 and XRCC3 may play a role in breast cancer occurrence and progression, but this role may be underlined by a mutual interaction between these genes. 相似文献
25.
Neutrophil extracellular traps cause airway obstruction during respiratory syncytial virus disease 下载免费PDF全文
Bart Cortjens Onno J de Boer Rineke de Jong Adriaan FG Antonis Yanaika S Sabogal Piñeros René Lutter Job BM van Woensel Reinout A Bem 《The Journal of pathology》2016,238(3):401-411
Human respiratory syncytial virus (RSV) is the most important cause of severe lower respiratory tract disease (LRTD) in young children worldwide. Extensive neutrophil accumulation in the lungs and occlusion of small airways by DNA‐rich mucus plugs are characteristic features of severe RSV–LRTD. Activated neutrophils can release neutrophil extracellular traps (NETs), extracellular networks of DNA covered with antimicrobial proteins, as part of the first‐line defence against pathogens. NETs can trap and eliminate microbes; however, abundant NET formation may also contribute to airway occlusion. In this study, we investigated whether NETs are induced by RSV and explored their potential anti‐viral effect in vitro. Second, we studied NET formation in vivo during severe RSV–LRTD in infants and bovine RSV–LRTD in calves, by examining bronchoalveolar lavage fluid and lung tissue sections, respectively. NETs were visualized in lung cytology and tissue samples by DNA and immunostaining, using antibodies against citrullinated histone H3, elastase and myeloperoxidase. RSV was able to induce NET formation by human neutrophils in vitro. Furthermore, NETs were able to capture RSV, thereby precluding binding of viral particles to target cells and preventing infection. Evidence for the formation of NETs in the airways and lungs was confirmed in children with severe RSV–LRTD. Detailed histopathological examination of calves with RSV–LRTD showed extensive NET formation in dense plugs occluding the airways, either with or without captured viral antigen. Together, these results suggest that, although NETs trap viral particles, their exaggerated formation during severe RSV–LRTD contributes to airway obstruction. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
26.
M. Vidyadhari M. Sujatha P. Krupa Pratibha Nallari A. Venkateshwari 《Immunologic research》2017,65(4):853-861
Spontaneous abortion is the loss of pregnancy during an early gestational period. Interleukin-10 is an anti-inflammatory cytokine which plays an important role in successful pregnancy outcome. The aim of the study is to elucidate an association of IL-10 gene promoter polymorphisms (-1082G/A, -819 C/T, -592C/A) in spontaneous abortions from Telangana state of South India. The present population-based retrospective case-control triad study includes a total of 80 case families with spontaneous abortions and 100 control families with medically terminated pregnancies. Peripheral blood from all the couples and fetal tissues of <20 weeks of gestation were collected. Genotype analysis was carried out by a standard amplification refractory mutation system–polymerase chain reaction followed by agarose gel electrophoresis. The strength of the association between IL-10 gene promoter polymorphisms and spontaneous abortions were measured by odd ratios and their respective 95% confidence intervals. Haplotype analysis was carried out for the three polymorphisms to establish an association of specific haplotypes with spontaneous abortions. The increased frequency of AA genotype and A allele of -1082G/A, TT genotype and T allele of -819C/T, and AA genotype and A allele of -592C/A was observed in case fetuses and case mothers compared to their respective controls. Haplotype analysis revealed that A-C-A, G-C-A haplotypes in fetuses and haplotypes A-C-C, G-T-C, A-T-A, and G-C-A in mothers were associated with increased risk of spontaneous abortions. IL-10 gene promoter polymorphisms may act as a major genetic regulator in the etiology of spontaneous abortions with maternal genome imprinting effects. 相似文献
27.
Plonowski A Schally AV Letsch M Krupa M Hebert F Busto R Groot K Varga JL 《The Prostate》2002,52(3):173-182
BACKGROUND: Antagonists of growth hormone-releasing hormone (GHRH) such as JV-1-38 can inhibit androgen-independent prostate cancer directly by several mechanisms and/or indirectly by suppressing growth hormone/insulin-like growth factor-I (GH/IGF-I) axis. To shed more light on the mechanisms involved, the effects of JV-1-38 on PC-3 human prostate cancer were compared with those of somatostatin analog RC-160 in vivo and in vitro. METHODS: Nude mice bearing PC-3 tumors received JV-1-38 (20 microg), RC-160 (50 microg) or a combination of JV-1-38 and RC-160. The concentration of IGF-I in serum and the expression of mRNA for IGF-II and vascular endothelial growth factor (VEGF) in tumor tissue were investigated. RESULTS: In vivo, the final volume of PC-3 tumors treated with JV-1-38 was significantly lowered by 49% (P < 0.01), whereas RC-160 exerted only 30% inhibition (NS), compared with controls. Combined use of both compounds augmented tumor inhibition to 63% (P < 0.001). Serum IGF-I levels were decreased only in mice treated with RC-160. JV-1-38 suppressed mRNA for IGF-II in PC-3 tumors by 42%, whereas RC-160 alone or in combination with JV-1-38 caused a 65% reduction. JV-1-38 and RC-160 used as single drugs decreased the expression of VEGF by 50%, and their combination caused a 63% reduction. In vitro, JV-1-38 inhibited the proliferation of PC-3 cells by 39%. This effect could be partially reversed by addition of IGF-I to the serum-free medium. RC-160 alone did not affect the PC-3 cell growth in vitro, but in combination with JV-1-38 it augmented the antiproliferative effect of the GH-RH antagonist to 72%. Exposure to JV-1-38 in vitro reduced the expression of mRNA for IGF-II in PC-3 cells by 55% but did not change VEGF mRNA levels, whereas RC-160 had no effect. CONCLUSIONS: The antiproliferative effect of JV-1-38 was not associated with the suppression of serum IGF-I and was only partially correlated with the expression of IGF-II and VEGF in PC-3 tumors, suggesting that other mechanisms play a role in the antitumor action of GHRH antagonists. Nevertheless, the stronger inhibition of tumor growth after combined treatment with JV-1-38 and RC-160 indicates that the interference with multiple local stimulatory factors leads to an enhanced inhibition of prostate cancer. 相似文献
28.
Effective treatment of experimental ES-2 human ovarian cancers with a cytotoxic analog of luteinizing hormone-releasing hormone AN-207 总被引:2,自引:0,他引:2
The receptors for luteinizing hormone-releasing hormone (LHRH) are found in 80% of human ovarian carcinomas. These receptors can be used for targeted chemotherapy with cytotoxic analogs of LHRH, such as AN-207, consisting of 2-pyrrolinodoxorubicin (AN-201) linked to [D-Lys ]LHRH. We investigated the effects of AN-207 and AN-201 on the growth of LHRH receptor-positive ES-2 human ovarian cancers. The effects of the treatment on mRNA and protein levels of human epidermal growth factor (EGF) receptors (EGFR and HER-2) in ovarian tumors were determined by RT-PCR and immunoblotting. In Experiment 1, nude mice bearing ES-2 ovarian tumors were injected i.v. with 250 nmol/kg doses of AN-207, AN-201, the carrier [D-Lys ]LHRH, an unconjugated mixture of AN-201 and [D-Lys ]LHRH or vehicle. AN-207 caused a significant ( <0.01) 59.5% inhibition in tumor growth while its components were ineffective. In Experiment 2, mice with large ES-2 tumors were treated with AN-207 or AN-201 at 250 nmol/kg. Again, AN-207, but not AN-201, inhibited tumor growth. In Experiment 3, the site of action of AN-207 was investigated. The blockade of LHRH receptors with Cetrorelix partially suppressed the antitumor effect of AN-207. Treatment with AN-207 significantly ( <0.01) decreased the expression of mRNA for EGFR, and HER-2 by 27 and 34%, respectively, as compared to controls and reduced the receptor protein levels of EGFR and HER-2 by 35 and 36%, respectively ( <0.05). The results indicate that cytotoxic LHRH analog AN-207 could be considered for chemotherapy of ovarian cancers expressing LHRH receptors. 相似文献
29.
Plonowski A Varga JL Schally AV Krupa M Groot K Halmos G 《International journal of cancer. Journal international du cancer》2002,98(4):624-629
Vasoactive intestinal peptide (VIP) stimulates the proliferation and invasiveness of malignant prostatic cells. Receptors for VIP and the closely related growth hormone-releasing hormone (GH-RH) show considerable homology and are found in prostatic and other carcinomas. Among various analogs of GH-RH synthesized, JV-1-52 is a non-selective VIP/GH-RH antagonist, whereas JV-1-53 is a VIP antagonist devoid of GH-RH antagonistic effect. In our study, nude mice bearing PC-3 human androgen-independent prostate carcinomas were treated with JV-1-52 or JV-1-53 (20 microg/day, s.c.) for 28 days. Both antagonists produced a similar reduction in tumor volume (62-67%, p < 0.01) and tumor weight (59-62%; p < 0.05) vs. controls and extended tumor doubling-time from 9.1 to about 16 days (p < 0.05). To investigate the mechanisms involved, in another study we compared the effects of JV-1-53 with those of somatostatin analog RC-160. VIP antagonist JV-1-53 reduced tumor weight by 67% (p < 0.01) and suppressed the expression of mRNA for c-fos and c-jun oncogenes by about 34% (p < 0.05), without affecting serum levels of insulin-like growth factor-I (IGF-I). In contrast, RC-160 (50 microg/day) reduced serum IGF-I by 19% (p < 0.05), but did not significantly decrease tumor weight. mRNA for VIP and high affinity receptors for VIP were detected on PC-3 tumors. Our results suggest that VIP/GH-RH antagonists can inhibit the growth of androgen-independent prostate cancer by abrogating the autocrine/paracrine mitogenic stimuli of VIP. The ability of GH-RH antagonists to block tumoral VIP receptors, in addition to GH-RH receptors, could be potentially beneficial for prostate cancer therapy. 相似文献
30.
We present a technique for stimulating post-synaptic receptors with neurotransmitter locally at a single synapse and with a concentration profile that is comparable to endogenous stimulation. We modify the technique of iontophoresis to use a 0.1 microm electrode tip for local stimulation, and we combine it with fast capacitance compensation to achieve high-speed application from a high-resistance tip. Ejection of fluorescent dye from the electrode shows that transmitter can be limited to the width of a single synapse and to a time scale similar to an endogenous event. The speed and localization of transmitter is confirmed by iontophoretically stimulating single labeled synapses in cultured hippocampal neurons held under voltage clamp. The amount of transmitter ejected is linear and reproducible over a physiologically relevant range, making this technique useful for examining receptor kinetics and receptor insertion/removal. The system should be capable of delivering any charged neurotransmitter, and we show examples using glutamate and GABA. The technique is also combined with computer-controlled manipulation to study the strength and plasticity of multiple synapses in real-time. 相似文献