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991.
The immune response during aging and diabetes is disturbed and may be due to the altered migration of immune cells in an aged tissue. Our study should prove the hypothesis that age and diabetes‐related advanced glycation end products (AGEs) have an impact on the migration and adhesion of human T‐cells. To achieve our purpose, we used in vitro AGE‐modified proteins (soluble albumin and fibronectin [FN]), as well as human collagen obtained from bypass graft. A Boyden chamber was used to study cell migration. Migrated Jurkat T‐cells were analyzed by flow cytometry and cell adhesion by crystal violet staining. Actin polymerization was determined by phalloidin‐Alexa‐fluor 488‐labeled antibody and fluorescence microscopy. We found that significantly fewer cells (50%, p = 0.003) migrated through methylglyoxal modified FN. The attachment to FN in the presence of AGE‐bovine serum albumin (BSA) was also reduced (p < 0.05). In ex vivo experiments, isolated collagen from human vein graft material negatively affected the migration of the cells depending on the grade of AGE modification of the collagen. Collagen with a low AGE level reduced the cell migration by 30%, and collagen with a high AGE level by 60%. Interaction of the cells with an AGE‐modified matrix, but not with soluble AGEs like BSA‐AGE per se, was responsible for a disturbed migration. The reduced migration was accompanied by an impaired actin polymerization. We conclude that AGEs‐modified matrix protein inhibits cell migration and adhesion of Jurkat T‐cells.  相似文献   
992.
993.

Background and Objectives:

To evaluate the usefulness of laparoscopic varicocelectomy in the management of chronic scrotal pain.

Methods:

Between 2009 and 2011, 48 patients in total were treated with laparoscopic varicocelectomy for dull scrotal pain that worsened with physical activity and was attributed to varicoceles. All patients were followed up at 3 and 6 months and biannually thereafter with a physical examination, visual analog scale score, and ultrasonographic scan in selected cases.

Results:

The mean age was 38.2 years (range, 23–54 years). The mean follow-up period was 19.6 months (range, 6–26 months). Bilateral varicoceles were present in 7 patients (14.6%), and a unilateral varicocele was present in 41 (85.4%). The varicocele was grade 3 in 27 patients (56.3%), grade 2 in 20 (41.6%), and grade 1 in 1 (2.1%). The mean preoperative visual analog scale score was 4.8 on a scale from 0 to 10. The mean postoperative visual analog scale score at 3 months was 0.8. After the procedure, 42 patients (87.5%) had a significant improvement in the visual analog scale score (P < .001); 5 (10.4%) had symptom improvement, although it was not statistically significant; and 1 (2.1%) remained unchanged. During follow-up, we observed 5 recurrences (10.4%) whereas de novo hydrocele formation was identified in 4 individuals (8.3%).

Conclusion:

Laparoscopic varicocelectomy is efficient in the treatment of symptomatic varicoceles with a low complication rate. However, careful patient selection is necessary because it appears that individuals presenting with sharp, radiating testicular pain and/or a low-grade varicocele are less likely to benefit from this procedure.  相似文献   
994.
The association between tumor size and survival in patients with intrahepatic cholangiocarcinoma (ICC) undergoing surgical resection is controversial. We sought to define the incidence of major and microscopic vascular invasion relative to ICC tumor size, and identify predictors of microscopic vascular invasion in patients with ICC ≥5 cm. A total of 443 patients undergoing surgical resection for ICC between 1973 and 2011 at one of 11 participating institutions were identified. Clinical and pathologic data were evaluated using uni- and multivariate analyses. As tumor sized increased, the incidence of microscopic vascular invasion increased: <3 cm, 3.6 %; 3–5 cm, 24.7 %; 5–7 cm, 38.3 %; 7–15 cm, 32.9 %, ≥15 cm, 55.6 %; (p?<?0.001). Increasing tumor size was also found to be associated with worsening tumor grade. The incidence of poorly differentiated tumors increased with increasing ICC tumor size: <3 cm, 9.7 %; 3–5 cm, 19.8 %; 5–7 cm, 24.2 %; 7–15 cm, 21.1 %; >15 cm, 31.6 % (p?=?0.04). The presence of perineural invasion (odds ratio [OR]?=?2.98) and regional lymph node metastasis (OR?=?4.43) were independently associated with an increased risk of microscopic vascular invasion in tumors ≥5 cm (both p?<?0.05). Risk of microscopic vascular invasion and worse tumor grade increased with tumor size. Large tumors likely harbor worse pathologic features; this information should be considered when determining therapy and prognosis of patients with large ICC.  相似文献   
995.

Purpose

In recent years, several endoscopic techniques have been explored in thyroid and parathyroid surgery, but only few gained acceptance among patients and surgeons. Based on extensive human cadaver and animal studies, we developed a technique for transoral partial parathyroidectomy (TOPP), which was performed for the first time in a patient with primary hyperparathyroidism (pHPT). We now report on results and the acceptance of this new technique 2 years after its implementation.

Methods

A pilot study was initiated to recruit a total of 10 patients with benign sporadic pHPT and a preoperatively localized parathyroid adenoma eligible for initial parathyroidectomy. The study protocol was approved by the ethics committee, and an insurance for unforeseen complications and risks was procured. Data of all patients evaluated and operated were prospectively collected, and follow-up examinations were carried out for 19 months on average, which included clinical examinations; ultrasonography; Ear, Nose, and Throat (ENT) investigations; and blood testing.

Results

Between January 2010 and May 2012, 75 patients with pHPT and a preoperative localized parathyroid adenoma were eligible for TOPP. After detailed information about the transoral procedure, only five (7 %) female patients consent to undergo TOPP. In three patients, a parathyroid adenoma could be removed via the transoral access, In two patients, the procedure had to be converted to the conventional technique. Median time until resection of a parathyroid adenoma was 122 min (range, 45–175). One patient had a transient recurrent laryngeal nerve palsy, while one patient suffered from a transient palsy of the right hypoglossal nerve and a slight but persisting dysgeusia. Three patients developed a hematoma of the mouth floor and swallowing problems. In four patients, the visual analog scale (VAS) pain score was high (>7) within the first 2 postoperative days.

Conclusions

Although TOPP is feasible, it is poorly accepted by patients and its complication rate is high. Thus, TOPP is nonsense with currently available devices.  相似文献   
996.
997.
The β-blockers carvedilol and metoprolol provide important therapeutic strategies for heart failure treatment. Therapy with metoprolol facilitates the control by phosphodiesterase PDE3, but not PDE4, of inotropic effects of catecholamines in human failing ventricle. However, it is not known whether carvedilol has the same effect. We investigated whether the PDE3-selective inhibitor cilostamide (0.3 μM) or PDE4-selective inhibitor rolipram (1 μM) modified the positive inotropic and lusitropic effects of catecholamines in ventricular myocardium of heart failure patients treated with carvedilol. Right ventricular trabeculae from explanted hearts of nine carvedilol-treated patients with terminal heart failure were paced to contract at 1 Hz. The effects of (-)-noradrenaline, mediated through β1-adrenoceptors (β2-adrenoceptors blocked with ICI118551), and (-)-adrenaline, mediated through β2-adrenoceptors (β1-adrenoceptors blocked with CGP20712A), were assessed in the absence and presence of the PDE inhibitors. The inotropic potency, estimated from –logEC50s, was unchanged for (-)-noradrenaline but decreased 16-fold for (-)-adrenaline in carvedilol-treated compared to non-β-blocker-treated patients, consistent with the previously reported β2-adrenoceptor-selectivity of carvedilol. Cilostamide caused 2- to 3-fold and 10- to 35-fold potentiations of the inotropic and lusitropic effects of (-)-noradrenaline and (-)-adrenaline, respectively, in trabeculae from carvedilol-treated patients. Rolipram did not affect the inotropic and lusitropic potencies of (-)-noradrenaline or (-)-adrenaline. Treatment of heart failure patients with carvedilol induces PDE3 to selectively control the positive inotropic and lusitropic effects mediated through ventricular β2-adrenoceptors compared to β1-adrenoceptors. The β2-adrenoceptor-selectivity of carvedilol may provide protection against β2-adrenoceptor-mediated ventricular overstimulation in PDE3 inhibitor-treated patients. PDE4 does not control β1- and β2-adrenoceptor-mediated inotropic and lusitropic effects in carvedilol-treated patients.  相似文献   
998.

Purpose

The hepatotoxic potential of the analgesic flupirtine has attracted increased attention over the past years. Recently, risk minimisation measures such as maximum treatment duration of 2 weeks have been requested by the European Medicines Agency (EMA). This study was conducted to further elucidate the clinical pattern of flupirtine-induced liver injury (FILI).

Methods

Seven FILI patients were ascertained in all Berlin hospitals in the Berlin Case–control Surveillance Study (FAKOS) between 2002 and 2011. Furthermore, we reviewed the severe cases of flupirtine-associated hepatotoxicity included in the adverse drug reaction database of the Federal Institute for Drugs and Medical Devices (BfArM) in Germany from between 1991 and 2012.

Results

All seven FILI patients of FAKOS were hospitalised. Six of them were female, mean age was 55 years, and the most common symptoms were fatigue and jaundice. Three patients developed acute liver failure (ALF). Discontinuation of flupirtine invariably led to clinical and laboratory improvement. Review of the BfArM cases (n?=?248) showed female sex predominance and high prevalence of jaundice and ALF. Time to onset of symptoms was less than 2 weeks in 9 % of the patients with respective data.

Conclusions

Our results corroborate previous findings on FILI’s clinical pattern and on its potentially severe course. Although the hepatotoxic risk might be higher after the first 2 weeks of treatment, earlier onset of severe FILI cannot be ruled out. Postauthorisation safety studies are needed to evaluate EMA’s risk minimisation measures and to quantify flupirtine’s risk according to its duration of use.  相似文献   
999.
1000.
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   
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