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41.
Journal of Neurology - Cognitive dysfunction affects 40–60% of individuals with multiple sclerosis (MS). The neuropsychological profile commonly consists of a subcortical pattern of deficits,...  相似文献   
42.
Naphthoquinones, such as menadione, display lower toxicity than anthracyclins used in cancer chemotherapy. Novel anti-leukaemic compounds comprised of chloro-amino-phenyl naphthoquinones with substitutions on the benzoic ring were developed. Structure–activity relationship studies indicated that the analogue with both methyl and amine substitutions (named TW-92) was the most efficient in killing leukaemic cells. Treatment of U-937 promonocytic cells with TW-92 induced apoptotic or necrotic cell death, dependent on incubation and dose conditions. TW-92 induced rapid phosphorylation of p38 mitogen-activated protein kinase (p38MAPK) and of extracellular signal-regulated protein kinases (ERK1/2). The generation of apoptosis was preceded by intracellular H2O2 accumulation accompanied by glutathione depletion, the former inhibited by di-phenyl-iodonium (DPI), an inhibitor of NADPH oxidase. TW-92 induced swelling of isolated rat liver mitochondria, indicative of a direct effect on mitochondria. Apoptosis in intact cells was accompanied by a decrease in mitochondrial membrane potential, cytochrome c release and caspase activation. In addition, the level of Mcl-1, an anti-apoptotic regulatory protein, was down-regulated, whereas the expression of the pro-apoptotic BAX was elevated. Finally, TW-92 exerted strong pro-apoptotic and necrotic effects in primary acute myeloid leukaemia samples when given in submicromolar concentrations. Together, these findings demonstrate that TW-92 may provide an effective anti-leukaemic strategy.  相似文献   
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Although malignant melanoma is rare in children, its incidence is steadily increasing, and it is potentially lethal. Few studies have examined head and neck melanoma in children, and even fewer have focused on the histopathologic features of melanoma within this anatomic region. To further the understanding of this entity, we examined pathology specimens from nine subjects age 18 years and younger with an original diagnosis of head or neck melanoma. The anatomic locations of these primary melanomas were the face and nose (n = 4), scalp and neck (n = 4), and ear (n = 1). The cases included seven superficial spreading melanomas, one unclassified (possible nodular) melanoma, and one melanoma in situ. No melanomas demonstrating desmoplastic or spindle cell morphologies were noted upon review. Breslow depth ranged from 0 to 2.9 mm (mean 1.3 mm, median 0.6 mm), with Clark level ranging from I to V. Pagetoid scatter was found in eight cases. Other notable features included regression (n = 5), ulceration (n = 1), and associated melanocytic nevus (n = 4). We did not observe any small cell variants; all nine cases had an epithelioid appearance. Nor was any melanoma‐associated mortality observed at last follow‐up (mean 60.4 mos, median 48 mos, range 2–174 mos). These histopathologic features were consistent with adult‐type melanoma, which is in agreement with other histopathologic studies of melanoma in children.  相似文献   
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Metastases from bladder cancer to the bones of the hands or feet are rare and usually present after the diagnosis of the primary lesion has been made. This case report describes a 76-year-old man presenting with initial signs of infection of the right foot. Subsequent bone scan revealed multiple bony metastases and hydronephrosis raising the possibility of a primary bladder tumour that was later confirmed by urine cytology and fine needle aspiration of the foot.  相似文献   
48.
Dopamine transporter (DAT) imaging with (123)I-FP-CIT ((123)I-N-omega-fluoropropyl-2beta-carbomethoxy-3beta-(4-iodophenyl)nortropane) SPECT is frequently used to detect loss of nigrostriatal cells in parkinsonism. Recent (123)I-beta-CIT ((123)I-2beta-carbomethoxy-3beta-(4-iodophenyl)tropane) studies have shown a significant increase in striatal-to-nonspecific beta-CIT binding ratios after treatment with selective serotonin reuptake inhibitors (SSRIs). Due to similarities between (123)I-beta-CIT and (123)I-FP-CIT (both are derived from cocaine and show relatively high affinity for the DAT and the serotonin transporter [SERT]), we hypothesized that quantification of striatal (123)I-FP-CIT binding may be influenced by SSRIs. Moreover, we hypothesized that (123)I-FP-CIT in humans binds not only to DATs but also to central and peripheral SERTs. METHODS: To study the influence of the SSRI paroxetine on (123)I-FP-CIT binding to DATs in the striatum, we conducted a double-blind, placebo-controlled, crossover study with paroxetine in 8 healthy young male control subjects. In addition, we studied whether paroxetine was able to block (123)I-FP-CIT binding in SERT-rich brain areas and in lung tissue, as lung tissue contains a considerable amount of SERTs. Participants were pretreated for 2 d with paroxetine (20 mg/d) or placebo at 2 sessions (crossover design), and brain SPECT was performed 1 and 3 h after (123)I-FP-CIT injection, whereas lung uptake was measured 2 h after injection. RESULTS: Compared with placebo pretreatment, we found after paroxetine pretreatment a statistically significant increase (approximately 10%) in specific striatal-to-nonspecific (123)I-FP-CIT binding ratios at 3 h after injection, a time point at which striatal (123)I-FP-CIT binding ratios are stable. In addition, after paroxetine treatment, statistically significantly lower binding ratios were found in SERT-rich brain areas (e.g., at 1 h after injection, midbrain-to-cerebellar ratios were approximately 90% lower) as well as significantly lower uptake in lung tissue was found (approximately 40% lower after paroxetine). CONCLUSION: In this study we show that the quantification of striatal (123)I-FP-CIT binding to DAT is significantly increased by the SSRI paroxetine in humans. To our knowledge, this is the first study which shows that (123)I-FP-CIT binds in vivo in humans not only to DATs but also to central SERTs and SERTs in lung tissue.  相似文献   
49.
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   
50.

Background

Hydrocele is abnormal collection of serous fluid in the tunica vaginalis or a patent processus vaginalis. It is commonly encountered in our practice and often requires surgical treatment. However in our setting and in many underdeveloped countries, availability of general anaesthetic service is poor due to lack of trained personnel and equipment.

Objectives

To ascertain the practicability and acceptability of hydrocelectomy under sedation and local anaesthesia in Nigerian adults with hydrocele

Patients and Methods

A prospective study was carried out over a two year period on patients that had hydrocelectomy at the surgery unit of the Obafemi Awolowo University Teaching Hospitals Complex, Wesley Guild Hospital, Ilesa. Consecutive patients with diagnosis of hydrocele who consented had hydrocelectomy using intramuscular diazepam sedation and spermatic-cord block with 0.5% plane xylocaine and the scrotum infiltrated with same along the line of incision.

Results

Fifty adult patients were studied: age range 15–94 years. Eighty percent of the patients had unilateral hydrocele and the commonest type was vaginal hydrocele (94%). All patients had hydrocelectomy, 96% were under local anaesthesia while 4% were converted to general anaesthesia. All patients except one prefer to have future surgery under such local anaesthesia and sedation.

Conclusion

Hydrocelectomy under local anaesthesia and sedation is practicable and was tolerated and accepted by the adults patients studied.  相似文献   
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