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101.
Withaferin A (WFA), an active compound from Withania somnifera, is widely researched for its anti-inflammatory, cardioactive and central nervous system effects. However, antiplatelet, anticoagulant, and profibrinolytic properties of WFA have not been studied. In this study, the anticoagulant activities of WFA were measured by monitoring activated partial thromboplastin-time (aPTT), prothrombin time (PT), fibrin polymerization, platelet aggregation, thrombus formation, and the activities of cell-based thrombin and activated factor X (FXa). The effects of WFA on the expressions of plasminogen activator inhibitor type 1 (PAI-1) and tissue-type plasminogen activator (t-PA) were also tested in tumor necrosis factor-α (TNF-α) activated human umbilical vein endothelial cells (HUVECs). Our data showed that WFA inhibited thrombin-catalyzed fibrin polymerization and platelet aggregation, FeCl3-induced thrombus formation, prolonged aPTT and PT significantly and inhibited the activities and production of thrombin and FXa. WFA prolonged in vivo and ex vivo bleeding time and inhibited TNF-α induced PAI-1 production. Furthermore, PAI-1/t-PA ratio was significantly decreased by WFA. Collectively, these results indicate that WFA possesses antithrombotic activities and suggest that the current study could provide bases for the development of new anticoagulant agents.  相似文献   
102.

Purpose

We investigated the influence of positive surgical margins (PSMs) and their locations on biochemical recurrence (BCR) according to risk stratification and surgical modality.

Methods

A total of 1,874 post-radical-prostatectomy (RP) patients of pT2–T3a between 2000 and 2010 at three tertiary centers, and who did not receive neoadjuvant/adjuvant therapy, were included in this study. Patients were stratified according to BCR risk: low risk (PSA <10, pT2a-b, and pGS ≤6), intermediate risk (PSA 10–20 and/or pT2c and/or pGS 7), and high risk (PSA >20 or pT3a or pGS 8–10). The median follow-up was 43 months.

Results

PSMs were a significant predictor of BCR in both the intermediate- and high-risk-disease groups (P = .001, HR 2.1, 95 % CI 1.3–3.4; P < .001, HR 2.8, 95 % CI 2.0–4.1). Positive apical margin was a significant risk factor for BCR in high-risk disease (P = .003, HR 2.0, 95 % CI 1.2–3.3), but not in intermediate-risk disease (P = .06, HR 1.7, 95 % CI 0.9–3.1). Positive bladder neck margin was a significant risk factor for BCR in both intermediate- and high-risk disease (P < .001, HR 5.4, 95 % CI 2.1–13.8; P = .001, HR 4.5, 95 % CI 1.8–11.4). In subgroup analyses, robotic RP provided comparable BCR-free survival regardless of risk stratification. Patients with PSMs showed similar BCR-free survival between open and robotic RP (log-rank, P = .897).

Conclusions

Post-RP PSMs were a significantly independent predictor of disease progression in high-risk disease as well as intermediate-risk disease. Both positive apical and bladder neck margins are also significant risk factors of BCR in high-risk disease. Patients with PSMs showed similar BCR-free survival between open and robotic surgery.  相似文献   
103.

Background

Living donor pancreas transplantation (LDPT) reduces the number of deaths of diabetic patients on dialysis and of candidates on the waiting lists and helps to overcome the organ shortage. Stringent criteria must be applied to minimize the risk of metabolic complications for living donors. The Japanese Pancreas and Islet Transplantation Association (JPITA) proposed LDPT guidelines in 2010. In this study, we retrospectively evaluated glucose metabolism of the patients who underwent distal pancreatectomy (DP) according to the donor criteria of the LDPT guidelines proposed by the JPITA.

Methods

Fifty-two nondiabetic patients who underwent DP were divided into 2 groups according to the donor criteria: indication group (IG, n = 14) who had age ≤ 65, hemoglobin A1c (HbA1c) < 5.9%, and body mass index (BMI) < 25 kg/m2. The other patients were placed in the no indication group (NG, n = 38). Clinical data and percent resected volume (PRV) of each pancreas as determined by multi–detector row computed tomography volumetry were compared between the 2 groups.

Results

During the follow-up period (median 12 months), 14 patients (27%) developed new-onset diabetes within a median onset time of 10 months (range 3–24 months) postoperatively. No patient in the IG developed new-onset diabetes. On the other hand, 37% of the patients in the NG developed new-onset diabetes. There were significant between-group differences in changes in preoperative serum fasting glucose and HbA1c levels, whereas there were no significant between-group differences in preoperative serum albumin or body weight. Multivariate analysis identified preoperative HbA1c (odds ratio 51.6, P = .002) and PRV (odds ratio 2.07, P = .033) as independent risk factors for new-onset diabetes.

Conclusion

Living donor criteria in the LDPT guidelines proposed by the JPITA are appropriate for prevention of glucose metabolic complications in donors. Further long-term follow-up studies of living donors' metabolic function are needed to clarify the safety of the donor.  相似文献   
104.

Purpose

To identify predictors of incidental prostate cancer following Holmium laser enucleation of the prostate (HoLEP).

Methods

We retrospectively analyzed 458 consecutive patients who underwent HoLEP. Patients were classified into two groups: patients who received prostate biopsy prior to HoLEP (biopsy group, n = 174) and patients who did not (non-biopsy group, n = 284). The two groups were compared. Logistic regression analysis was performed to determine the predictive factors.

Results

A total of 27 patients (5.9 %) were incidentally diagnosed with prostate cancer. The incidence of prostate cancer was not significantly different between the two groups (biopsy group vs. non-biopsy group: 6.9 vs. 5.3 %, p = 0.48). Using multivariate analysis, a hypoechoic lesion identified by transrectal ultrasonography (TRUS) was the only predictor of incidental prostate cancer (odds ratio 2.829; 95 % confidence interval 1.061–7.539; p = 0.038). In the biopsy group, there were no significant differences in baseline characteristics including prostate size, prostate-specific antigen (PSA), PSA density, digital rectal examination (DRE) findings, and TRUS findings, between patients with and without prostate cancer. However, in the non-biopsy group, a hypoechoic lesion was found more frequently in patients with prostate cancer (prostate cancer vs. benign prostatic hyperplasia: 20.0 vs. 3.3 %, p = 0.02).

Conclusions

Prior negative prostate biopsy does not rule out the possibility of prostate cancer after HoLEP. The presence of a hypoechoic lesion on TRUS might be helpful to predict incidental prostate cancer after HoLEP in patients with normal PSA and negative DRE. Prostate biopsy prior to HoLEP should be considered in these patients.  相似文献   
105.
A 25-year-old woman was referred to our hospital with persistent upper abdominal pain. Preoperative imaging studies revealed a hilar bile duct stricture with portal venous encasement, and the patient underwent curative resection involving extended left hepatectomy and segmental portal vein resection. The pathological findings demonstrated a well-differentiated tubular adenocarcinoma of the bile duct with regional lymph node metastasis (stage IIIB according to the UICC TNM classification), as well as the overexpression of p53 proteins and the K-ras gene mutation in tumor cells. The patient has shown no evidence of recurrence in the 10 months since the operation. Although there are several reports of relatively young adults with cholangiocarcinoma, the majority of such patients demonstrate either an anomalous arrangement of the pancreaticobiliary duct system or primary sclerosing cholangitis. The absence of any morphological abnormalities in this patient’s biliary system implicates de novo carcinogenesis as the most likely cause of the cholangiocarcinoma.  相似文献   
106.

Background

Sorafenib is currently recommended as first-line therapy for patients with intermediate or advanced hepatocellular carcinoma (HCC) per Barcelona Clinic Liver Cancer staging. However, the median overall survival (OS) with sorafenib in these patients is 10.7 months with an overall response rate of 2 %. We retrospectively investigated the long-term outcomes and prognostic factors with reductive hepatectomy and sequential percutaneous isolated hepatic perfusion (PIHP) for refractory intermediate or advanced HCC.

Methods

A total of 68 patients who had intermediate or advanced stage HCC without extrahepatic metastases were scheduled for reductive hepatectomy plus PIHP. All patients underwent reductive hepatectomy and PIHP with mitomycin C 20–40 mg/m2 and/or doxorubicin 60–120 mg/m2 1–3 months after surgery (mean, 1.51 times/patient).

Results

The objective response rate of PIHP was 70.6 % (complete plus partial response). The median OS of all 68 patients was 25 months, and the 5-year OS rate was 27.6 %. Univariate and multivariate analyses indicated that tumor response to PIHP and normalization of serum des-γ-carboxy prothrombin concentrations after PIHP were independent prognostic factors for OS.

Conclusions

The median OS of the study population treated by reductive hepatectomy and sequential PIHP was 25 months. This treatment strategy can offer a possible curative treatment to patients with refractory intermediate and advanced HCC.  相似文献   
107.

Purpose

The objective of the study was to validate the previously reported lookup Table and Bladder Cancer Research Consortium (BCRC) nomogram in predicting cancer-specific mortality (CSM) and all-cause mortality (ACM) after radical cystectomy using an external cohort from South Korea.

Methods

The study comprised 409 patients. Discrimination was quantified with the concordance index. The relationship between the model-derived and actual CSM and ACM was graphically explored within calibration plots. Clinical net benefit was evaluated by decision curve analysis.

Results

Of the 409 patients, 147 (35.9 %) had died from various causes. One hundred two deaths were attributable to bladder cancer. For CSM at 5 years, the bootstrap-corrected concordance indices of the American Joint Committee on Cancer (AJCC) staging system, lookup Table, and BCRC nomogram were 71.8 % (95 % confidence interval [CI] 66.9–76.5), 73.0 % (95 % CI 67.9–78.0), and 76.2 % (95 % CI 71.6–80.9), respectively. For ACM at the same time point, the discrimination accuracies of these models were 70.7 % (95 % CI 66.7–74.6), 72.8 % (95 % CI 68.5–76.9), and 76.2 % (95 % CI 72.3–80.2), respectively. The calibration plots tended to exaggerate both survival outcomes in all models. When compared to the lookup Table as well as the AJCC staging system, the BCRC nomogram performed well across a wide range of threshold probabilities using decision curve analysis.

Conclusions

The BCRC nomogram was characterized by higher accuracy and larger potential clinical benefit compared to the lookup Table. However, there is a great need for additional models that consider outcomes of patients for whom the existing models do not apply.  相似文献   
108.
Poisoning with organophosphorus compounds (OPCs) poses a serious threat worldwide. OPC‐induced mortality can be significantly reduced by prophylactic administration of reversible acetylcholinesterase (AChE) inhibitors. The only American Food and Drug Administration (FDA)‐approved substance for such pre‐treatment (to soman exposure) is presently pyridostigmine, although its efficacy is controversial. In search for more efficacious and broad‐spectrum alternatives, we have assessed in vivo the mortality‐reducing efficacy of a group of five compounds with known AChE inhibitory activity (pyridostigmine, physostigmine, ranitidine, tacrine and K‐27), when given in equitoxic dosage (25% of LD01) 30 min before exposure to the OPC terbufos sulfone. Protection was quantified in rats by determining the relative risk of death (RR) using Cox analysis, with RR = 1 for animals given only terbufos sulfone, but no pre‐treatment. All tested AChE inhibitors reduced terbufos sulfone‐induced mortality significantly (p ≤ 0.05) as compared with the non‐treatment group (RR = 1: terbufos sulfone only). Best in vivo protection from terbufos sulfone‐induced mortality was achieved, when K‐27 was given before terbufos sulfone exposure (RR = 0.06), which was significantly (P ≤ 0.05) superior to the pre‐treatment with all other tested compounds, for example tacrine (RR = 0.21), pyridostigmine (RR = 0.28), physostigmine (RR = 0.29) and ranitidine (RR = 0.33). The differences in efficacy between tacrine, pyridostigmine, physostigmine and ranitidine were not statistically significant. Prophylactic administration of an oxime (such as K‐27) in case of imminent OPC exposure may be a viable option. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
109.
Trichothecenes are a large family of structurally related toxins mainly produced by Fusarium genus. Among the trichothecenes, T-2 toxin and deoxynivalenol (DON) cause the most concern due to their wide distribution and highly toxic nature. Trichothecenes are known for their inhibitory effect on eukaryotic protein synthesis, and oxidative stress is one of their most important underlying toxic mechanisms. They are able to generate free radicals, including reactive oxygen species, which induce lipid peroxidation leading to changes in membrane integrity, cellular redox signaling, and in the antioxidant status of the cells. The mitogen-activated protein kinases signaling pathway is induced by oxidative stress, which also induces caspase-mediated cellular apoptosis pathways. Several new metabolites and novel metabolic pathways of T-2 toxin have been discovered very recently. In human cell lines, HT-2 and neosolaniol (NEO) are the major metabolites of T-2 toxin. Hydroxylation on C-7 and C-9 are two novel metabolic pathways of T-2 toxin in rats. The metabolizing enzymes CYP3A22, CYP3A29, and CYP3A46 in pigs, as well as the enzymes CYP1A5 and CYP3A37 in chickens, are able to catalyze T-2 toxin and HT-2 toxin to form the C-3′–OH metabolites. Similarly to carboxylesterase, CYP3A29 possesses the hydrolytic ability in pigs to convert T-2 toxin to NEO. T-2 toxin is able to down- or upregulate cytochrome P-450 enzymes in different species. The metabolism of DON in humans is region-dependent. Free DON and DON-glucuronide are considered to be the biomarkers for humans. The masked mycotoxin DON-3-β-d-glucoside can be hydrolyzed to free DON in the body. This review will provide useful information on the progress of oxidative stress as well as on the metabolism and the metabolizing enzymes of T-2 toxin and DON. Moreover, the literature will throw light on the blind spots of metabolism and toxicological studies in trichothecenes that have to be explored in the future.  相似文献   
110.
库丽  王强 《中国药业》2014,(1):40-42
目的探讨I类切口围手术期抗菌药物预防使用的改进措施。方法对医院I类切口围手术期抗菌药物预防使用的干预效果进行分析,设非干预组、干预组进行对照性研究。结果干预后I类切口围手术期预防应用抗茵药物的总体预防使用率、药物的选择、围手术期用药时间和用法用量等指标的合格率明显上升,但也存在不足之处。结论行政督导在短时间内效果明显,但也要重视业务学习,才能进一步提高I类切口围手术期抗茵药物的合理使用水平。  相似文献   
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