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111.

Objective

Aicardi‐Goutières syndrome (AGS) is an early‐onset encephalopathy resembling congenital viral infection that is characterized by basal ganglia calcifications, loss of white matter, cerebrospinal fluid (CSF) lymphocytosis, and elevated interferon‐α levels in the CSF. Studies have shown that AGS is an autosomal‐recessive disease linked to mutations in 5 genes, encoding the 3′‐repair DNA exonuclease 1 (TREX1), the 3 subunits of ribonuclease H2 (RNASEH2A–C), and sterile alpha motif domain and HD domain–containing protein 1 (SAMHD1). In this study we further characterized the phenotypic spectrum of this disease.

Methods

Clinical and laboratory data were obtained from 26 patients fulfilling the clinical diagnostic criteria for AGS. Genomic DNA was screened for mutations in all 5 AGS genes by direct sequencing, and sera were analyzed for autoantibodies.

Results

In 20 patients with AGS, 20 mutations, 12 of which were novel, were identified in all 5 AGS genes. Clinical and laboratory investigations revealed a high prevalence of features (some not previously described in patients with AGS) that are commonly seen in patients with systemic lupus erythematosus (SLE), such as thrombocytopenia, leukocytopenia, antinuclear antibodies, erythematous lesions, oral ulcers, and arthritis, which were observed in 12 (60%) of 20 patients with AGS. Moreover, the coexistence of AGS and SLE, was for the first time, demonstrated in 2 patients with molecularly proven AGS.

Conclusion

These findings expand the phenotypic spectrum of lupus erythematosus in AGS and provide further insight into its disease mechanisms by showing that activation of the innate immune system as a result of inherited defects in nucleic acid metabolism could lead to systemic autoimmunity.
  相似文献   
112.
Mah JT  Low ES  Lee E 《Drug discovery today》2011,16(17-18):800-809
SNPs can alter protein function and phenotype, leading to altered pharmacogenomic drug profiles. The exponential number of SNPs makes it impossible to perform wet laboratory experiments to determine the biological significance of each one. However, bioinformatics tools can be used to screen for potentially deleterious SNPs that might affect important drug targets before further investigation by wet laboratory techniques. As there are numerous web-based bioinformatics tools, much time and effort is needed to select the most appropriate tool to use. Here, we review state-of-the-art bioinformatics tools to help researchers analyze and select the most promising SNPs for drug discovery in the shortest time possible.  相似文献   
113.
114.

Background:

Bile duct obstruction is associated with hepatic accumulation of leukocytes and liver injury. The aim of this study was to evaluate the effect of simvastatin on cholestasis-induced liver inflammation and tissue damage.

Experimental approach:

C57BL/6 mice were treated with simvastatin (0.02 and 0.2 mg·kg−1) and vehicle before and after undergoing bile duct ligation (BDL) for 12 h. Leukocyte recruitment and microvascular perfusion in the liver were analysed using intravital fluorescence microscopy. CXC chemokines in the liver were determined by enzyme-linked immunosorbent assay. Liver damage was monitored by measuring serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Hepatic levels of myeloperoxidase (MPO) were also determined.

Key results:

Administration of 0.2 mg·kg−1 simvastatin decreased ALT and AST by 87% and 83%, respectively, in BDL mice. This dose of simvastatin reduced hepatic formation of CXC chemokines by 37–82% and restored sinusoidal perfusion in cholestatic animals. Moreover, BDL-induced leukocyte adhesion in sinusoids and postsinusoidal venules, as well as MPO levels in the liver, was significantly reduced by simvastatin. Notably, administration of 0.2 mg·kg−1 simvastatin 2 h after BDL induction also decreased cholestatic liver injury and inflammation.

Conclusions and implications:

These findings show that simvastatin protects against BDL-induced liver injury. The hepatoprotective effect of simvastatin is mediated, at least in part, by reduced formation of CXC chemokines and leukocyte recruitment. Thus, our novel data suggest that the use of statins may be an effective strategy to protect against the hepatic injury associated with obstructive jaundice.  相似文献   
115.
This study examined health-related quality of life and parental stress among pediatric neuromuscular patients with or without home mechanical ventilation. Parents completed the Parenting Stress Index or Stress Index for Parents of Adolescents, depending on their child's age. The Pediatric Quality of Life Inventory measured quality of life in children with neuromuscular disease. One hundred and nine families participated; 19 (17%) families had a child with neuromuscular disease requiring home mechanical ventilation. Overall, children on home mechanical ventilation had significantly lower mean total Pediatric Quality of Life Inventory scores than nonventilated children (47.9 versus 61.5, respectively; P = 0.013). No significant difference in mean total stress scores was found between parents of pediatric neuromuscular patients with or without home mechanical ventilation. Despite their child's lower health-related quality of life, parents of pediatric neuromuscular patients requiring home mechanical ventilation did not report significantly higher parental stress than parents of nonventilated children or parents in the normative sample. We postulated that for parents living with the constant demands of caring for their child with neuromuscular disease requiring home mechanical ventilation, these caretaking demands, over time, had become part of "normal" life and were not identified as creating additional stress.  相似文献   
116.
BACKGROUND: Prostatic adenocarcinoma is exceptionally associated with cutaneous lesions. We describe a patient with cutaneous lymphangitis and paraneoplastic ichtyosis related to prostatic cancer. CASE REPORT: A 92 year-old man had been treated for five years for a prostatic carcinoma. An angiomatous lesion developed with in 3 months near the right breast. Physical examination revealed axillary node enlargement, a large skin angiomatous lesion, and ichtyosis. The skin biopsy of the angiomatous skin lesion demonstrated its prostatic origin with carcinomatous metastases in the lymphatic vessels. The ichtyosis was considered as paraneoplastic. DISCUSSION: Cutaneous metastases from prostatic carcinoma are rare. Less than 1 p. 100 of cutaneous metastases are of prostate origin despite the high frequency of this cancer in the general population. The clinical aspects - angiomatous lesion and paraneoplastic ichtyosis - are exceptional.  相似文献   
117.
INTRODUCTION: Pruritus in the infant is predominantly related to common dermatosis. General causes remain exceptional. We report two cases of pruritus in infants revealing anicteric cholestasis. OBSERVATIONS: Case no 1. A thirteen month-old boy had exhibited pruritus since the age of 2 months. The clinical examination was non-specific. Biological explorations revealed an isolated and moderate rise in total bilary acids. The search for mutations in the genes of a familial fibrogenic cholestasis was negative. The diagnosis retained was hypercholanemia. Treatment combined ursodesoxycholic acid and rifampicine, which controlled the pruritus and normalized the bilary acid levels. Case no 2. A twenty-one month-old boy had exhibited pruritus since the age of 2 months and delayed growth. The clinical examination was unspecific. The biological explorations revealed cholestasis with normal delta GT, moderate cytolysis and liposoluble vitamin deficiency. The hepatic biopsy was normal. The diagnosis retained was familial fibrogenic cholestasis. Treatment combined ursodesoxycholic acid and rifampicine, which controlled the pruritus and normalized the hepatic parameters. DISCUSSION: Non-dermatological isolated pruritus is rare in infants. These two observations illustrate two abnormalities in bilary acid transport. Hypercholanemia is a faulty canalization of bilary acids by the hepatocyte. Familial fibrogenic cholestasis is a default in the elimination of these bilary acids. Such pathologies must be evoked because specific treatment will treat the symptoms and avoid the evolution of familial fibrogenic cholestasis towards cirrhosis.  相似文献   
118.
BACKGROUND: External genital wart is the most frequent sexually transmitted disease. While there are guidelines for management and treatment, no data about primary care of this viral disease is available in France. So, we conducted a survey on French dermatologists'management of external genital warts. METHODS: In July and August 2001, a questionnaire - including questions on physicians and patients, sexually transmitted diseases, partners, clinical and viral evaluations, treatments, and follow-up - was mailed to 652 French dermatologists (randomization of 20 p. 100 of French dermatologists). RESULTS: Three hundred and fifty (53 p. 100) responses were returned. Dermatologists were mainly exclusively office practitioners (58 p. 100). Thirty-six percent of them were taking care of more than 3 patients per month with external genital warts. Patients were essentially men and immunocompetent. Only 52 p. 100 of physicians systematically performed a sexually transmitted disease evaluation, 38 p. 100 a partner evaluation, and 17 p. 100 a local evaluation for external genital warts. Biopsy was occasionally performed by 48 p. 100 of physicians, mainly in order to confirm diagnosis. Viral genotyping was rare. Cryotherapy (84 to 93 p. 100) and podophyllotoxin (40 to 55 p. 100) were the two treatments used as first line therapy, while laser (61 to 71 p. 100), and imiquimod (39 to 48 p. 100) were second line therapies. Sixty-three percent of physicians proposed a systematic clinical control after clinical recovery. CONCLUSION: This large survey represents an overview on general practice concerning external genital warts among French dermatologists. Our study points out the lack of global management (loco-regional, partner, and STD evaluation) of the disease by dermatologists.  相似文献   
119.
PURPOSE: To report long-term pulmonary, thyroid, and ocular complications in patients who had conditioning regimens including total body irradiation (TBI) before bone marrow transplantation (BMT). METHODS AND MATERIALS: Between June 1986 and December 1995, 478 patients received TBI in our institution. The present study includes 186 adult patients who had complete remission lasting one year or more after BMT. There were 108 males and 78 females. Median age was 36.5 years (range 15-60). Initial diagnoses were lymphomas (50%), acute lymphoid leukemias (16%), acute myeloid leukemias (16%), chronic myeloid leukemia (13%), aplastic anemia (3%), and myelodysplasia (2%). At the time of BMT, 43.5% of patients were in complete response and 56.5% in partial response. Treatment consisted of a single dose TBI at 10 Gy in 9% and fractionated TBI delivering 12 to 13.5 Gy in 6 fractions in 91%. From 1986 to October 1991, TBI was performed in lateral position with 9 MV energy (57% of patients) and thereafter in alternate prone and supine positions with 15 MV energy (43%). Chemical conditioning regimen was cyclophosphamide (60 mg/kg at D-4 and D-3) in 69% and CBV (cyclophosphamide 1500 mg/m(2) from D-6 to D-3, BCNU 300 mg/m(2) at D-6, VP-16 200 mg/m(2) from D-6 to D-4) in 25%. Fifty eight percent of patients received autologous and 42% allogeneic BMT. All patients had clinical, biologic, and functional examinations at one-year intervals. RESULTS: Median follow-up from BMT was 49 months (range 12-136). Late pulmonary effects were observed only in functional explorations, without clinical effect, including restrictive syndrome in 8% and alteration in the diffusing capacity of carbon monoxide in 12%. No patient showed clinical thyroid symptoms, and 10% developed biologic dysfunction: hypothyroidism (6.5%), thyroiditis (3%), and Basedow disease (0.5%). Ocular complications occurred in 29.5%, including cataract (15%), dry syndrome (13%), and keratitis (1.5%). In univariate and multivariate analysis, pulmonary complications were statistically increased by chronicle graft vs. host disease (GVHD) vs. no (p = 0.02), prone and supine vs. lateral TBI position (p = 0.02), and with 15 MV vs. 9 MV beam energy (p = 0.02). Cataract occurred less frequently with fractionated than with single-dose TBI (p = 0.000002). No differences were observed regarding age, sex, initial diagnosis, status at the time of BMT, conditioning chemotherapy regimen, and total dose of TBI. CONCLUSION: From this retrospective study it was shown that long-term complications of TBI were not symptomatic in most patients. The role of parameters of irradiation and especially position of treatment and beam energy should be emphasized and assessed with a longer follow-up.  相似文献   
120.
PURPOSE: Evidence-based medicine guidelines based on venographic end points recommend in-hospital prophylaxis with low-molecular-weight heparin (LMWH) in patients having elective hip surgery. Emerging data suggest that out-of-hospital use may offer additional protection; however, uncertainty remains about the risk-benefit ratio. To provide clinicians with a practical pathway for translating clinical research into practice, we systematically reviewed trials comparing extended out-of-hospital LMWH prophylaxis versus placebo. DATA SOURCES: Studies were identified by 1) searching PubMed, MEDLINE, and the Cochrane Library Database for reports published from January 1976 to May 2001; 2) reviewing references from retrieved articles; 3) scanning abstracts from conference proceedings; and 4) contacting pharmaceutical companies and investigators of the original reports. STUDY SELECTION: Randomized, controlled trials comparing extended out-of-hospital prophylaxis with LMWH versus placebo in patients having elective hip arthroplasty. DATA EXTRACTION: Two reviewers extracted data independently. Reviewers evaluated study quality by using a validated four-item instrument. DATA SYNTHESIS: Six of seven original articles met the defined inclusion criteria. The included studies were double-blind trials that used proper randomization procedures. Compared with placebo, extended out-of-hospital prophylaxis decreased the frequency of all episodes of deep venous thrombosis (placebo rate, 150 of 666 patients [22.5%]; relative risk, 0.41 [95% CI, 0.32 to 0.54; P < 0.001]), proximal venous thrombosis (placebo rate, 76 of 678 patients [11.2%]; relative risk, 0.31 [CI, 0.20 to 0.47; P < 0.001]), and symptomatic venous thromboembolism (placebo rate, 36 of 862 patients [4.2%]; relative risk, 0.36 [CI, 0.20 to 0.67; P = 0.001]). Major bleeding was rare, occurring in only one patient in the placebo group. CONCLUSIONS: Extended LMWH prophylaxis showed consistent effectiveness and safety in the trials (regardless of study variations in clinical practice and length of hospital stay) for venographic deep venous thrombosis and symptomatic venous thromboembolism. The aggregate findings support the need for extended out-of-hospital prophylaxis in patients undergoing hip arthroplasty surgery.  相似文献   
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