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991.

Objectives

The association of anti-tumor necrosis factor therapy with opportunistic infections in rheumatoid arthritis (RA) patients has been reported. The goal of this study was to clarify the clinical characteristics and the risk factors of RA patients who developed Pneumocystis jirovecii pneumonia (PCP) during etanercept therapy.

Methods

We conducted a multicenter, case–control study in which 15 RA patients who developed PCP were compared with 74 RA patients who did not develop PCP during etanercept therapy.

Results

PCP developed within 26?weeks following the first injection of etanercept in 86.7% of the patients. All PCP patients presented with a rapid and severe clinical course and the overall mortality was 6.7%. Independent risk factors were identified using multivariate analysis and included age ≥65?years [hazard ratio (HR) 3.35, p?=?0.037], coexisting lung disease (HR 4.48, p?=?0.009), and concomitant methotrexate treatment (HR 4.68, p?=?0.005). In patients having a larger number of risk factors, the cumulative probability of developing PCP was significantly higher (p?<?0.001 for patients with two or more risk factors vs. those with no risk factor, and p?=?0.001 for patients with one risk factor vs. those with no risk factor).

Conclusion

Physicians must consider the possibility of PCP developing during etanercept therapy in RA patients, particularly if one or more risk factors are present.  相似文献   
992.
Due to the widespread acceptance of gastric and esophageal endoscopic submucosal dissections (ESDs), the number of medical facilities that perform colorectal ESDs has grown and the effectiveness of colorectal ESD has been increasingly reported in recent years. The clinical indications for colorectal ESD at the National Cancer Center Hospital, Tokyo, Japan include laterally spreading tumor (LST) nongranular type lesions >20 mm and LST granular type lesions >30 mm. In addition, 0-IIc lesions >20 mm, intramucosal tumors with nonlifting signs and large sessile lesions, all of which are difficult to resect en bloc by conventional endoscopic mucosal resection (EMR), represent potential candidates for colorectal ESD. Rectal carcinoid tumors less than 1 cm in diameter can be treated simply, safely, and effectively by endoscopic submucosal resection using a ligation device and are therefore not indications for ESD. The en bloc resection rate was 90%, and the curative resection rate was 87% for 806 ESDs. The median procedure time was 60 minutes, and the mean size for resected specimens was 40 mm (range, 15 to 150 mm). Perforations occurred in 23 (2.8%) cases, and postoperative bleeding occurred in 15 (1.9%) cases, but only two perforation cases required emergency surgery (0.25%). ESD was an effective procedure for treating colorectal tumors that are difficult to resect en bloc by conventional EMR. ESD resulted in a higher en bloc resection rate as well as decreased invasiveness in comparison to surgery. Based on the excellent clinical results of colorectal ESDs in Japan, the Japanese healthcare insurance system has approved colorectal ESD for coverage.  相似文献   
993.
Hereditary transthyretin (TTR) amyloidosis is a fatal disease causing systemic organ dysfunctions. Histopathological studies revealed that thyroid glands are major target tissues. However, details about thyroid functions remain to be fully elucidated in this disease. For patient treatment, liver transplantation (LT) reportedly prolongs patient survival, but thyroid gland function after LT still remains poorly understood. In this study, we investigated the thyroid functions in 101 patients with hereditary TTR amyloidosis and the effects of LT on thyroid functions in those patients. In addition, we investigated histopathological and biochemical findings of thyroid specimens obtained at autopsy. Disease duration and age at examination inversely correlated with serum levels of free triiodothyronine (fT3) in hereditary TTR amyloidosis. On the contrary, in patients who underwent transplantation, time from disease onset to transplantation and age at transplantation clearly correlated with serum fT3and thyroid stimulating hormone (TSH) levels. In autopsy studies, amounts of thyroid amyloid deposits in patients with transplantation were significantly lower than those in patients without transplantation. Mass spectrometric analyzes also revealed that proportions of wild-type (WT) TTR in thyroid amyloid deposits in patients with hereditary TTR amyloidosis who underwent transplantations were higher than those in patients without transplantation. Thyroid hormone functions may diminish according to the disease progression. LT could prevent thyroid dysfunction in hereditary TTR amyloidosis.  相似文献   
994.
Objective: To evaluate effectiveness and safety of tocilizumab (TCZ) in biologic-naive Japanese patients with rheumatoid arthritis (RA) in real-world settings, and to analyze the relationship between disease duration and clinical outcomes.

Methods: The FIRST Bio study was a postmarketing surveillance study of intravenous TCZ in biologics-naive patients who had a prior inadequate response or were intolerant to ≥1 conventional synthetic disease-modifying antirheumatic drug (csDMARD). Effectiveness, safety, and concomitant csDMARD administration were assessed.

Results: Of the 839 patients analyzed, 72.3% completed 52 weeks of treatment. The Clinical Disease Activity Index (CDAI) remission rate at week 52 was 36.8%. Contributing factors for CDAI remission were younger age, early disease stage, and no comorbidities. Health Assessment Questionnaire Disability Index ≤0.5 was achieved in 65.1% of patients, and was significantly associated with disease duration. Discontinuation of concomitant methotrexate (MTX) and glucocorticoids (GCs) was possible in 19.3% and 34.1% of patients, respectively, without decreasing remission rate. The incidence (events/100 patient-years) of serious adverse events was 18.09, the most common being infection.

Conclusion: These data validate the importance of TCZ treatment in the early stages of RA in biologic-naive patients to achieve increased effectiveness. The safety profile of TCZ was reconfirmed. Furthermore, TCZ therapy may allow discontinuation of concomitant MTX and GCs without affecting remission.  相似文献   

995.
Urotensin-II (UII), a cyclic dodecapeptide with potent cardiovascular effects, has recently been shown to be abundantly expressed in the human kidney and excreted in human urine. To investigate whether UII acts as an autocrine/paracrine growth factor for renal epithelial cells, we have studied the effects of human UII (hUII) on DNA synthesis, cytosolic free Ca(2+) concentration ([Ca(2+)](i)), ERK activation, and protooncogene (c-myc) expression in a porcine renal epithelial cell line (LLCPK1). hUII stimulated [(3)H]thymidine uptake into quiescent cells in a dose-dependent manner (10(-9) to 10(-7) M); this effect was inhibited by a protein kinase C inhibitor (GF109203X), a MAPK kinase inhibitor (PD98059), and a calcium channel blocker (nicardipine). Neither phosphatidyl inositol-3 kinase inhibitors (LY294002, wortmannin) nor p38 kinase inhibitor (SB203580) affected the hUII-induced DNA syntheses. hUII rapidly (within 5 min) and dose-dependently (10(-9) to 10(-7) M) increased [Ca(2+)](i) in fura-2-loaded cells. hUII also caused a rapid and transient activation of ERK1/2 and induction of c-myc. LLCPK1 cells expressed UII mRNA and its receptor GPR14 mRNA, as determined by RT-PCR, and released UII-like immunoreactivity into media. Neutralization of endogenous UII by anti-hUII antibody, but not nonimmune serum, significantly suppressed DNA synthesis. These data suggest that hUII is an autocrine/paracrine growth factor for renal epithelial cells via activation of both protein kinase C and ERK1/2 pathways as well as Ca(2+) influx via voltage-dependent Ca(2+) channels.  相似文献   
996.
In an effort to identify tumor suppressor gene(s) associated with the frequent loss of heterozygosity observed on chromosome 6q25-q27, we constructed a contig derived from the sequences of bacterial artificial chromosomeP1 bacteriophage artificial chromosome clones defined by the genetic interval D6S1581-D6S1579-D6S305-D6S1599-D6S1008. Sequence analysis of this contig found it to contain eight known genes, including the complete genomic structure of the Parkin gene. Loss of heterozygosity (LOH) analysis of 40 malignant breast and ovarian tumors identified a common minimal region of loss, including the markers D6S305 (50%) and D6S1599 (32%). Both loci exhibited the highest frequencies of LOH in this study and are each located within the Parkin genomic structure. Whereas mutation analysis revealed no missense substitutions, expression of the Parkin gene appeared to be down-regulated or absent in the tumor biopsies and tumor cell lines examined. In addition, the identification of two truncating deletions in 3 of 20 ovarian tumor samples, as well as homozygous deletion of exon 2 in the lung adenocarcinoma cell lines Calu-3 and H-1573, supports the hypothesis that hemizygous or homozygous deletions are responsible for the abnormal expression of Parkin in these samples. These data suggest that the LOH observed at chromosome 6q25-q26 may contribute to the initiation andor progression of cancer by inactivating or reducing the expression of the Parkin gene. Because Parkin maps to FRA6E, one of the most active common fragile sites in the human genome, it represents another example of a large tumor suppressor gene, like FHIT and WWOX, located at a common fragile site.  相似文献   
997.
Experience of primary percutaneous coronary intervention (PCI) for young adults with acute myocardial infarction (AMI) due to sequelae of Kawasaki disease (KD) has been extremely limited. In the present report on three young adults (two males and one female; age 20-35 years) with AMI, we performed primary PCI and intravascular ultrasound imaging (IVUS). Case 1 underwent thrombectomy alone in the proximal left circumflex coronary artery, and subsequent IVUS depicted a large aneurysm with an asymmetrically intimal thickening and a residual thrombus in the culprit. Case 2 underwent balloon dilation with adjunctive intracoronary thrombolysis in the proximal left anterior descending coronary artery (LAD), and IVUS during follow-up coronary angiography (CAG) delineated a regressed giant aneurysm with a markedly intimal thickening in the culprit. Case 3, with past history highly suggesting KD, underwent balloon dilation in the proximal LAD, and follow-up CAG as well as IVUS revealed a neoaneurysmal formation in the culprit. In all of the patients, PCI was angiographically effective at the acute phase without complication. Follow-up CAG performed 3-6 months after the procedure revealed no restenosis in all three cases, but a new coronary aneurysm still remained in case 3. Although case 1 and case 2 had no obvious history of KD, the vessel wall morphology from IVUS closely resembled the coronary sequelae after KD, suggesting that they might have antecedent incomplete KD. These cases suggest that primary PCI against coronary sequelae of KD in young AMI patients might be safe and effective in the short term.  相似文献   
998.
Drinking alcohol sometimes causes cardiac arrhythmia, but the precise mechanism remains unknown. To study the mechanism, we investigated the effects of ethanol exposure on the beating rate of cultured chick cardiac myocytes. Primary cultures of cardiac myocytes were prepared from the ventricles of 14-day-old chick embryos and then treated with ethanol which, in the range of 0.3 to 1.5 vol%, increased the beating rate in a dose-dependent manner. Ethanol (0.6 vol%) caused an increase in the beating rate, but disopyramide (5 μ g/ml) and procainamide (10 μ g/ml), Na+ and K+ channel blockers, inhibited the increase in the beating rate significantly. Neither lidocaine (5 μ g/ml) nor mexiletine (2 μ g/ml), Na+ channel blockers, nor calcium antagonist verapamil (5 ng/ml) inhibited the increase. However, tetraethylammonium chloride (ranging from 15 to 30 mmol/1), a K+ channel blocker, inhibited the increase. These findings indicate that ethanol increases the beating rate of cultured chick cardiac myocytes via the activation of the K+ channel. This experimental model may be useful in studying the effect of ethanol on the K+ channel.  相似文献   
999.
1000.
We aimed to assess the effect of aliskiren treatment on blood pressure, albuminuria, and kidney function in patients with chronic kidney disease (CKD). We conducted a prospective, open-label study of 67 patients with CKD who were already being treated with other antihypertensives. Inclusion criteria were blood pressure (BP) ≥130/80 mmHg, albuminuria ≥30 mg/g, and estimated glomerular filtration rate (eGFR) >30 ml/min/1.73 m2. Subjects were treated with 150 mg/day aliskiren, which was increased to 300 mg/day for the 24-week study period. Aliskiren effectively reduced both systolic and diastolic BP, plasma renin activity (PRA), serum aldosterone concentration, albuminuria, urinary N-acetyl-glucosaminidase, and urinary β2-microglobulin levels. Although eGFR was significantly decreased after 4 weeks of aliskiren treatment, it recovered to a pretreatment level within 12 weeks of treatment initiation. There were no significant differences in the percent reduction of albuminuria or changes of eGFR levels when the subjects were divided into three groups on the basis of baseline eGFR (stages 1/2, 3, and 4) and the presence or absence of diabetes mellitus (DM group and non-DM group). Furthermore, in patients not treated with renin-angiotensin-aldosterone-system (RAAS) inhibitors, including angiotensin receptor blockers or angiotensin-converting enzyme inhibitors at baseline, changes in eGFR were significantly increased compared with those already treated with RAAS inhibitors at baseline. Aliskiren administration reduced BP, PRA, serum aldosterone levels, and albuminuria, while maintaining eGFR, regardless of the presence or absence of DM or the degree of eGFR.  相似文献   
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