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A lysogenic strain of Pseudomonas aeruginosa was cultured from the dialysis fluid of a patient on chronic hemodialysis treatment whose blood contained hepatitis B surface antigen (HB8Ag). When this bacterium was incubated for 4 to 7 days with serum containing HB8Ag or with purified HB8Ag, a loss of the HB8Ag-specific immunological reactivity was observed. Bacteriophages can be induced from the isolated P. aeruginosa with mitomycin C; the phages, after purification on CsCl gradients, also lyse P. aeruginosa strain 25102 (ATCC). Subsequent to gradient centrifugation of the lysate, a fraction was found with a density around 1.40 g/ml that inactivated HB8Ag after a 4-h incubation at 37 C as determined by counterelectrophoresis and hemagglutination inhibition. The activity was not found in appreciable amounts in other gradient fractions. The electron microscope shows that the active fraction contains envelope vesicles of 45 to 60 nm in diameter. In spite of their loss in HB8Ag activity, the HB8Ag particles (22nm) appeared morphologically intact. These findings suggest that an enzyme(s) is present in the vesicle fraction which inactivates antigenic determinants on HB8Ag particles. Thus, the presence of these bacteria in environments such as feces, dialysis tanks, and contaminated drinking water may prevent the detection of HB8Ag.  相似文献   
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An infant girl with elevated blood lactate, pyruvate, and plasma branched-chain amino acids was diagnosed with dihydrolipoamide dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4) deficiency. Activities of the pyruvate dehydrogenase complex and E3 from patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in cultured skin fibroblasts, respectively. Western blot analysis demonstrated that the amount of E3 protein in fibroblasts from the patient and her father was about half of controls, while Northern blot analysis showed normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs from the patient revealed two mutations in separate alleles. One is a single base insertion of an extra adenine in the last codon of the leader peptide sequence (TAC-->TAAC) leading to a nonsense mutation which results in the premature termination of the precursor E3 polypeptide (Y35X). The other is a missense mutation due to substitution of guanine for adenine, causing an Arg-->Gly substitution at amino acid 460 of the mature protein (R460G) which triggers the loss of E3 activity probably by structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the parents demonstrated that the nonsense mutation was inherited from the father and the missense mutation was inherited from the mother.   相似文献   
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Risk estimates promulgated by various radiation protection authorities in recent years have become increasingly more complex. Early "integral" estimates in the form of health effects per 0.01 person-Gy (per person-rad) or per 10(4) person-Gy (per 10(6) person-rad) have tended to be replaced by "differential" estimates which are age- and sex-dependent and specify both minimum induction (latency) and duration of risk expression (plateau) periods. These latter types of risk estimate must be used in conjunction with a life table in order to reduce them to integral form. In this paper, the life table has been used to effect a comparison of the organ and tissue risk estimates derived in several recent reports. In addition, a brief review of life-table methodology is presented and some features of the models used in deriving differential coefficients are discussed. While the great number of permutations possible with dose-response models, detailed risk estimates and proposed projection models precludes any unique result, the reduced integral coefficients are required to conform to the linear, absolute-risk model recommended for use with the integral risk estimates reviewed.  相似文献   
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In the past two decades, thousands of documents in the field of prostatitis have been published. This bibliometric analysis aimed to assess the characteristics, hotspots and frontiers trend of global scientific output on prostatitis. With the trend of moderate growth, altogether 2,423 papers were reviewed. The leading role of the United States in global prostatitis research was obvious, while China had developed rapidly in recent years. Queen's University and JOURNAL OF UROLOGY were the most prolific affiliation and journal respectively. Nickel, J. C made the greatest contribution to the field of prostatitis. Five hotspots have been confirmed: (a) male infertility associated with prostatitis and the molecular mechanisms; (b) diagnosis and treatment of prostatitis; (c) inflammation, pain and bladder irritation symptoms; (d) relationship between chronic prostatitis/chronic pelvic pain syndrome, benign prostatic hyperplasia and prostate cancer; (e) epidemiology, complications of prostatitis and improvement of acupuncture. This bibliometric analysis reveals that the international cooperation was becoming more and more close. Hotspot analysis shows that the molecular mechanism of prostatitis will be a hotspot in the future, mainly focussing on inflammatory immunity and oxidative stress.  相似文献   
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There are limited data on the impact of COVID-19 in children with a kidney transplant (KT). We conducted a prospective cohort study through the Improving Renal Outcomes Collaborative (IROC) to collect clinical outcome data about COVID-19 in pediatric KT patients. Twenty-two IROC centers that care for 2732 patients submitted testing and outcomes data for 281 patients tested for SARS-CoV-2 by PCR. Testing indications included symptoms and/or potential exposures to COVID-19 (N = 134, 47.7%) and/or testing per hospital policy (N = 154, 54.8%). Overall, 24 (8.5%) patients tested positive, of which 15 (63%) were symptomatic. Of the COVID-19-positive patients, 16 were managed as outpatients, six received non-ICU inpatient care and two were admitted to the ICU. There were no episodes of respiratory failure, allograft loss, or death associated with COVID-19. To estimate incidence, subanalysis was performed for 13 centers that care for 1686 patients that submitted all negative and positive COVID-19 results. Of the 229 tested patients at these 13 centers, 10 (5 asymptomatic) patients tested positive, yielding an overall incidence of 0.6% and an incidence among tested patients of 4.4%. Pediatric KT patients in the United States had a low estimated incidence of COVID-19 disease and excellent short-term outcomes.  相似文献   
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BackgroundRadical/cytoreductive nephrectomy or nephron-sparing surgery may be thought to be not safe or unfeasible in some renal cell carcinoma (RCC) patients in which tumor is locally advanced or highly complicated. Neoadjuvant therapy may reduce the volume of the tumor, thus facilitates surgery. The aim the study is to evaluate the efficacy and safety of neoadjuvant combination of pazopanib or axitinib and PD-1-activated dendritic cell-cytokine-induced killer (PD-1/DC-CIK) cell immunotherapy in those patients.MethodsData from 16 RCC patients who received neoadjuvant pazopanib (Group P, n=9) or axitinib (Group A, n=7) plus PD-1/DC-CIK cells immunotherapy were reviewed retrospectively. A total of 9 participants that were potential candidates for radical/cytoreductive nephrectomy (RN/CN) had locally advanced tumor and 5 participants with partial nephrectomy (PN) absolute indications had highly complicated tumors. The efficacy outcomes were based on volume changes of the primary tumor, lymph nodes, and tumor thrombus in 13 participants with complete computed tomography (CT) imaging. The treatment-related toxicities and surgical complications were also reported.ResultsWith a median of 2.1 months treatment, the overall volume of the tumors decreased by a median of 42.30% [interquartile range (IQR): 19.37–66.78%]. Specifically, the median reduction of tumor volume was 88.77 and 15.50 cm3 in group P and group A, respectively (P=0.014). However, participants in Group P were more likely to experience grade 3 or 4 treatment-related adverse events (AEs) than those in Group A (44.4% vs. 0). Finally, all participants were candidates for appropriate surgery after neoadjuvant therapy (as assessed by the surgeon), and 10 participants accepted surgery, including 5 PN, 4 RN/CN, and 1 lymph node dissection. A solitary participant had Clavien grade IV acute renal failure required dialysis and another had grade II lymphatic leakage.ConclusionsNeoadjuvant combination of pazopanib or axitinib and PD-1/DC-CIK cells immunotherapy was well-tolerated and could effectively reduce the volume of tumors in locally advanced or highly complicated RCC patients.  相似文献   
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