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991.
992.
Dratviman-Storobinsky O Cohen Y Frenkel S Merhavi-Shoham E El SD Binkovsky N Pe'er J Goldenberg-Cohen N 《Investigative ophthalmology & visual science》2012,53(6):2611-2619
Purpose. RASSF1A inactivation in uveal melanoma (UM) is common and methylation-induced. We investigated the effect of RASSF1A re-expression on the UM phenotype in vivo and in vitro. Methods. The phenotypic effect of methylation-induced inactivation of RASSF1A in UM was explored using a stable RASSF1A-expressing UM-15 clone. RASSF1A expression was assessed using QRT-PCR. Proliferation was evaluated in vitro using MTT assays. Additionally, athymic NOD/SCID mice were injected subcutaneously or intraocularly with RASSF1A-expressing and -non-expressing UM-15 clones, and euthanized when tumors reached a volume of 1500 mm(3), or at 56 or 46 days, respectively. Tumor tissues, eyes, and livers were analyzed histologically. Results. In vitro analysis confirmed the lack of RASSF1A expression and full methylation of the RASSF1A promoter region in the UM-15 cell line, which was reversible following treatment with 5-Aza-2-deoxycytidine. Cells expressing exogenous RASSF1A showed slower proliferation than controls and regained sensitivity to cisplatin. Compared to mice injected with control cells, mice treated with UM-15 cells expressing exogenous RASSF1A did not acquire intraocular tumors, and their subcutaneous tumors were relatively delayed and small. Neither group had liver metastases. Conclusions. UM cells reduced tumorigenicity in the presence of activated RASSF1A. RASSF1A apparently has an important role in the development of UM, and its reactivation might be applied in the development of new treatments. 相似文献
993.
994.
Niklas Stabell Audun Stubhaug Trond Flægstad Emeran Mayer Bruce D. Naliboff Christopher S. Nielsen 《The journal of pain》2014,15(9):898-906
Widespread hyperalgesia is well documented among adult patients with irritable bowel syndrome (IBS), but little is known about pain sensitivity among adolescents with IBS. We examined pain sensitivity in 961 adolescents from the general population (mean age 16.1 years), including pain threshold and tolerance measurements of heat (forearm) and pressure pain (fingernail and shoulder) and cold pressor tolerance (hand). Adolescents with IBS symptoms (Rome III criteria) had lower heat pain thresholds compared to controls after adjustments for sex, comorbid pain, and psychological distress (mean difference = –.8°C; 95% confidence interval [CI] = ?1.6 to ?.04). Similar results were found for pressure pain threshold at the shoulder (mean difference = ?46 kPa; 95% CI = ?78 to ?13) and fingernail (mean difference = –62 kPa; 95% CI = ?109 to ?15), and for an aggregate of all 3 threshold measures (z-score difference = ?.4; 95% CI = ?.6 to ?.2), though pressure pain threshold differences were nonsignificant after the final adjustments for psychological distress. No difference of pain tolerance was found between the IBS cases and controls. Our results indicate that adolescents in the general population with IBS symptoms, like adults, have widespread hyperalgesia.PerspectiveThis is the first report of widespread hyperalgesia among adolescents with IBS symptoms in the general population, with lower pain thresholds found to be independent of sex and comorbid pain. Our results suggest that central pain sensitization mechanisms in IBS may contribute to triggering and maintaining chronic pain symptoms. 相似文献
995.
Deborah Pugin Brandon Foreman Gian Marco De Marchis Andres Fernandez J Michael Schmidt Barry M Czeisler Stephan A Mayer Sachin Agarwal Christine Lesch Hector Lantigua Jan Claassen 《Critical care (London, England)》2014,18(3):R103
Introduction
Seizures refractory to third-line therapy are also labeled super-refractory status epilepticus (SRSE). These seizures are extremely difficult to control and associated with poor outcome. We aimed to characterize efficacy and side-effects of continuous infusions of pentobarbital (cIV-PTB) treating SRSE.Methods
We retrospectively reviewed continuous electroencephalography (cEEG) reports for all adults with RSE treated with cIV-PTB between May 1997 and April 2010 at our institution. Patients with post-anoxic SE and those receiving cIV-PTB for reasons other than RSE were excluded. We collected baseline information, cEEG findings, side-effects and functional outcome at discharge and one year.Results
Thirty one SRSE patients treated with cIV-PTB for RSE were identified. Mean age was 48 years old (interquartile range (IQR) 28,63), 26% (N = 8) had a history of epilepsy. Median SE duration was 6.5 days (IQR 4,11) and the mean duration of cIV-PTB was 6 days (IQR 3,14). 74% (N = 23) presented with convulsive SE. Underlying etiology was acute symptomatic seizures in 52% (N = 16; 12/16 with encephalitis), remote 30% (N = 10), and unknown 16% (N = 5). cIV-PTB controlled seizures in 90% (N = 28) of patients but seizures recurred in 48% (N = 15) while weaning cIV-PTB, despite the fact that suppression-burst was attained in 90% (N = 28) of patients and persisted >72 hours in 56% (N = 17). Weaning was successful after adding phenobarbital in 80% (12/15 of the patients with withdrawal seizures). Complications during or after cIV-PTB included pneumonia (32%, N = 10), hypotension requiring pressors (29%, N = 9), urinary tract infection (13%, N = 4), and one patient each with propylene glycol toxicity and cardiac arrest. One-third (35%, N = 11) had no identified new complication after starting cIV-PTB. At one year after discharge, 74% (N = 23) were dead or in a state of unresponsive wakefulness, 16% (N = 5) severely disabled, and 10% (N = 3) had no or minimal disability. Death or unresponsive wakefulness was associated with catastrophic etiology (p = 0.03), but none of the other collected variables.Conclusions
cIV-PTB effectively aborts SRSE and complications are infrequent; outcome in this highly refractory cohort of patients with devastating underlying etiologies remains poor. Phenobarbital may be particularly helpful when weaning cIV-PTB. 相似文献996.
997.
Valentin C Pissard S Martin J Héron D Labrune P Livet MO Mayer M Gelbart T Schneider A Max-Audit I Cohen-Solal M 《Blood》2000,96(3):1130-1135
Three French families with triose phosphate isomerase (TPI) deficiency were studied, and 2 new mutations giving rise to null alleles were observed: a frameshift mutation with deletion of the 86-87 TG dinucleotide in codon 29 (TPI Alfortville) and a T-->A transversion in nucleotide 2 of the initiation codon (TPI Paris). The first mutation occurred in compound heterozygosity with the frequent E105D mutation. The second mutation occurred in association with the 2-nucleotide promoter variant (-43G,-46A). In a third family, the propositus was an E105D homozygote. In the TPI Paris family, the coinheritance of the -43,-46 promoter variant appeared to exert little, if any, effect on TPI enzyme activity, a finding consistent with 2 previous reports that questioned the putative role of the promoter polymorphism as a true deficiency variant. Similarly, the further coinheritance of glucose-6-phosphate dehydrogenase (G6PD) A- (202 G-->A/376 A-->G) appeared to have little effect on the observed phenotype. Compound heterozygosity for the E105D mutation with the null allele TPI Alfortville appeared to lead to a more severe clinical syndrome than did E105D homozygosity, suggesting that compound heterozygosity with null alleles may lead to more profound clinical abnormalities than homozygosity with missense alleles. A simple, rapid polymerase chain reaction and restriction enzyme procedure for the E105D mutation was developed for prenatal diagnosis in one family and subsequently used for screening in the other families. 相似文献
998.
Concordance of polymerase chain reaction with human immunodeficiency virus antibody detection 总被引:4,自引:0,他引:4
C R Horsburgh C Y Ou J Jason S D Holmberg A R Lifson J L Moore J W Ward G R Seage K H Mayer B L Evatt 《The Journal of infectious diseases》1990,162(2):542-545
To evaluate the correlation of detection of human immunodeficiency virus (HIV) by polymerase chain reaction (PCR) with detection of HIV antibody, 271 simultaneous serum and peripheral blood mononuclear cell samples were examined from 242 persons whose activities placed them at increased risk for HIV infection: 142 from homosexual men, 86 from hemophilic men, and 43 from heterosexual partners of HIV-infected persons. PCR was performed using the gag region primer pair SK38/39 and the env region primer pairs SK68/69 and CO71/72. Amplified HIV DNA was detected using specific oligomer probes. Of 63 HIV antibody-positive samples, 58 (92%) had HIV DNA by PCR. Of 208 HIV antibody-negative samples, 7 (3.4%) had HIV DNA by PCR. On follow-up, 4 of the latter persons were seropositive when next tested; 2 were well and antibody- and PCR-negative; 1 had died of a stroke before retesting. Thus, PCR detects HIV in most antibody-positive persons; detection is increased by use of multiple primer pairs. PCR-positive antibody-negative specimens may indicate HIV infection in which antibody has not yet developed or may be false-positive PCR results. When PCR is discordant with HIV antibody, testing of additional specimens and clinical follow-up are necessary to assess HIV infection status. 相似文献
999.
A double blind placebo controlled trial was performed to evaluate the effects of the aldose reductase inhibitor, ponalrestat, on symptomatic diabetic neuropathy. After a 4-week placebo run-in phase, 60 patients were 2:1 randomized to receive either 600 mg ponalrestat or placebo once daily over 12 months. Forty-six patients, 30 of whom were treated with ponalrestat and 16 with placebo, completed the study. Motor and sensory nerve conduction, thermal and vibration sensation thresholds, heart rate variation at rest, E/I ratio, pupillary dilation velocity and pupillary reflex latency were determined at baseline and after 6 and 12 months. Neuropathic symptom scores were assessed every 3 months. Among the fifteen nerve function parameters studied, only trends in favour of ponalrestat were noted for heart rate variation and E/I ratio after 6 months (P = 0.06), but no significant differences between the groups could be demonstrated during the study. No adverse reactions were observed. It is concluded that one-year treatment with ponalrestat has no beneficial effects on symptoms or electrophysiological parameters in diabetic neuropathy. 相似文献
1000.
Newmann S Sarin P Kumarasamy N Amalraj E Rogers M Madhivanan P Flanigan T Cu-Uvin S McGarvey S Mayer K Solomon S 《International journal of STD & AIDS》2000,11(4):250-253
A retrospective study was conducted on 134 HIV-infected females evaluated at an HIV/AIDS centre in south India to characterize their sociodemographics, HIV risk factors and initial clinical presentations. The mean age was 29 years; 81% were housewives; 95% were currently or previously married; 89% reported heterosexual sex as their only HIV risk factor; and 88% reported a history of monogamy. The majority were of reproductive age, thus the potential for vertical transmission of HIV and devastating impacts on families is alarming. Nearly half of these women initially presented asymptomatically implying that partner recruitment can enable early HIV detection. Single partner heterosexual sex with their husband was the only HIV risk factor for the majority of women. HIV prevention and intervention strategies need to focus on married, monogamous Indian women whose self-perception of HIV risk may be low, but whose risk is inextricably linked to the behaviour of their husbands. 相似文献