Functional association between the nef gene product and gag-pol region of HIV-1

AbstractNef gene function is diverse among virus isolates of primate immunodeficiency viruses. We found differential effects of nef mutation on the virus replication between two HIV-1 clones, NL432 and LAI. The nef mutation in NL432 affected the infectivity more severely compared with that in LAI, although the Nef functions of both clones were comparable. Analysis with a series of chimeric viruses between NL432 and LAI revealed that the gag-pol region was responsible for the differential effect of nef mutation. The functional association between Nef and gag-pol suggested that one of the potential targets of Nef was located within the gag-pol region

Downregulation of CD4 is required for maintenance of viral infectivity of HIV-1

AbstractDownregulation of virus receptors on the cell surface is considered to be important in preventing superinfection. HIV-1 encodes multiple gene products, Env, Vpu, and Nef, involved in downregulation of CD4, a major HIV-1 receptor. We found that simultaneous mutations in both vpu and nef severely impaired virus replication. We examined the involvement of CD4 downregulation mediated by Vpu and Nef in the modification of virus infectivity. The mutation in vpu increased CD4 incorporation into virions without affecting the Env content in it, inhibiting the attachment step of virions to the CD4-positive cell surface. Although a single mutation in nef suppresses virus infectivity via a CD4-independent mechanism, it could augment CD4 incorporation in virions in combination with a vpu mutation. These results indicated that CD4 downregulation was necessary for maintenance of Env function in the virion

Molecular mechanisms of acute radiation intestinal injury and its control

腸管は代表的な放射線高感受性組織であり、放射線治療においては腹部・骨盤領域の腫瘍への処方線量を制限するリスク臓器である。高線量の放射線により腸組織が損傷を受けると腸上皮幹細胞の喪失を誘発するが、この過程はp53 によって制御される陰窩細胞死過程と炎症性の免疫応答による増悪過程の2 段階のプロセスからなることが明らかにされつつある。本総説では、それぞれの過程の分子機構について概説し、急性放射線腸管障害を効果的に制御する方法について考察する。The intestinal tract is a typical radiosensitive tissue and a risk organ in radiotherapy that limits the prescribed dose to tumors in the abdominal and pelvic regions. High-dose radiation damage to intestinal tissue induces loss of intestinal stem cells, and it is becoming clear that this process consists of two steps: a crypt cell death process regulated by p53 and an exacerbation process by inflammatory immune responses. In this review, we will outline the molecular mechanisms of each process and discuss how to effectively control acute radiation intestinal injury

Neurogenic Tumor of The Chest Wall: A

A rare case of schwannoma of the chest wall is presented. A 65-year-old Japanese man had a painful mass, measuring 3×3cm, in the 10th intercostal space of the right back. A fine needle biopsy seemed to fail to prove a nature of the tumor. A computed tomography (CT) scan of the chest showed a well-demarcated low density mass with no invasion to the ribs, lung and pleura with the CT density being 30 Hounsfield unit. These findings were suggestive of a neurogenic tumor. The tumor was easily extirpated and a histological diagnosis was schwannoma

The outcome and a new ISN/RPS 2003 classification of lupus nephritis in Japanese

The outcome and a new ISN/RPS 2003 classification of lupus nephritis in Japanese.BackgroundA considerable diversity in prognosis is seen with lupus glomerulonephritis (LGN). Hence, the clinical usefulness of a recent International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification to judge the long-term outcome of human LGN has been investigated.MethodsWe studied retrospectively 60 subjects with LGN (7 males, 53 females, mean age of 33 years old) who underwent renal biopsies and were followed from 1 to 366 months, with a mean of 187 months. We diagnosed renal pathology as classes, active and sclerosing lesions, according to the new and WHO1995 classification of LGN, and analyzed the clinicopathologic factors affecting to the prognosis of LGN.ResultsNew classification got much higher consensus in the judgment of classes (98% vs. 83%, P = 0.0084). The group of Class IV-S (N = 6) or IV-G (N = 17) at initial biopsies showed higher rate of end-stage renal failure (ESRF) compared with that of Class I, II, III or V (40.9% vs. 2.6%, P < 0.001). The mean 50% renal survival time of Class IV was 189 ± 29 months, and patients with Class IV-S tended to have a poorer prognosis (95 ± 22 months for IV-S vs. 214 ± 35 months for IV-G, P = 0.1495). Class IV was also selected as the most significant risk factor for ESRF by stepwise model (P = 0.002). In subanalysis for ESRF in Class IV (-S or –G), treatment including methylprednisolone pulse therapy was only selected as a significant improving factor for primary outcome (P = 0.034). In addition, activity index was the significant risk factor of death and/or ESRF after initial renal biopsies (P = 0.043). As for actuarial patient death during all follow-up periods, complications with anti-phospholipid syndrome or nephrotic syndrome were significant risk factors (P = 0.013, P = 0.041, respectively).ConclusionNew ISN/RPS 2003 classification provided beneficial pathologic information relevant to the long-term renal outcome and the optimal therapy preventing ESRF and/or death in patients with LGN

Relationship between serum uric acid levels and chronic kidney disease in a Japanese cohort with normal or mildly reduced kidney function

Background: Some observational studies have shown the relationships between hyperuricemia and chronic kidney disease (CKD); however, the threshold of serum uric acid (SUA) for deterioration of kidney function and the association between SUA and kidney injury by baseline kidney function remains unclear. This study aimed to clarify the relationships between SUA and reduced kidney function. Methods: We analyzed a historical cohort of male Japanese individuals who underwent medical checkup between 1998 and 2007. Participants with baseline data and who were followed up for at least one year were included and stratified according to baseline kidney function. Kidney function was classified as normal [estimated glomerular filtration rate (eGFR) ≥ 90 ml/min/1.73 m2] or mildly reduced (eGFR 60-89 ml/min/1.73 m2). The outcome measured was kidney impairment defined as a decrease in eGFR to < 60 ml/min/1.73 m2. Associations between SUA and risk for outcome and eGFR slopes were assessed. Results: A total of 41632 subjects with mean age 45.4 years were included. During a mean follow-up of four years, 3186 (7.6%) subjects developed kidney dysfunction. Subjects with SUA ≥ 6.0 mg/dL had a significantly increased risk for kidney impairment compared with subjects with SUA of 4-4.9 mg/dL. SUA threshold levels were different according to baseline kidney function; SUA ≤ 7.0 and ≤ 6.0 mg/dL for normal and mildly reduced kidney function, respectively. Approximately the same trends were observed for eGFR slopes. Conclusion: In the general population, hyperuricemia appears to be a risk factor for kidney impairment in males. For participants with mild kidney dysfunction, even a slight elevation of SUA can be a risk factor. Copyright: © 2015 Toyama et al.This article has a supplementary figure. Please see the last page of the text

Combined pure red cell aplasia and autoimmune hemolytic anemia in systemic lupus erythematosus with anti-erythropoietin autoantibodies

金沢大学医薬保健研究域医学系A 42-year-old woman with systemic lupus erythematosus was admitted to our hospital because of severe anemia. Her bone marrow was almost normocellular and erythroblasts were nearly absent. Laboratory data showed elevated levels of lactate dehydrogenase and positive findings on Coombs\u27 tests. On the basis of these findings, her anemia was diagnosed as the overlap of pure red cell aplasia with autoimmune hemolytic anemia. Radioimmunoprecipitation assay revealed that her serum was positive for anti-erythropoietin antibodies before therapy. Furthermore, the autoantibodies inhibited proliferation of an erythropoietin-dependent cell line in a dose-dependent manner. Immunosuppressive treatment improved the anemia accompanied with disappearance of the autoantibodies. © 2008 Wiley-Liss, Inc