Another autosomal recessive form of focal glomerulosclerosis with neurological findings

We report four patients in a consanguineous family with focal segmental glomerulosclerosis (FSGS), early onset nephrotic syndrome, eventual end-stage renal failure, psychomotor retardation, seizures and microcephaly or brain atrophy without hiatus hernia. Other characteristic dysmorphic features were convergent strabismus and narrow forehead. One patient had enamel hypoplasia of the upper incisors and deviation of bilateral thumbs to palm side. We could not detect an NPHS2 mutation in this family. We propose that this may be another autosomal recessive syndrome with FSGS and neurological findings. Received: 18 January 2001 / Revised: 14 August 2001 / Accepted: 14 August 2001     

Immunohistochemical study of mononuclear cell infiltrates in squamous cell carcinoma of oral cavity and paranasal sinus

Serial frozen sections were prepared from 22 squamous cell carcinomas of oral cavity and paranasal sinus. Mononuclear cell infiltrates were stained by the biotin-avidin-horseradish peroxidase method using a panel of 10 mouse monoclonal antibodies to human leukocyte antigens. The degree of infiltration was graded from + + + (marked) to - (absent). The infiltration of anti-Leu-4-reactive cells (Leu-4+ cells) was grade + + or + + + in 14 of 22 cases. In 13 of 22 cases, infiltration of Leu-3a + 3b+ cells (helper/inducer T lymphocytes) was grade + + (moderate). In 5 of 20 cases, infiltration of Leu-2a+ cells (cytotoxic/suppressor T lymphocytes) was grade + +. As for B lymphocytes, infiltration of Leu-12+ cells was grade + + in only 2 of 19 cases. In conclusion, T lymphocyte infiltrates were commonly seen in squamous cell carcinoma in oral cavity and paranasal sinus and the number of patients with grade + + infiltration of helper/inducer T lymphocytes significantly predominated over that of patients with infiltration of cytotoxic/suppressor T lymphocytes grade + +.     

Context-dependent cortical activation in response to financial reward and penalty: an event-related fMRI study

An event-related fMRI technique was used to assess neural responses to financial reward and penalty during a simple gambling task. We attempted to determine whether brain activities are dependent on the unique context of an event sequence. Thirty-six healthy volunteers participated in the study. The task was to guess the color of the suit of a card on each trial and to respond by pressing a button. Every correct response ("win") and incorrect response ("loss") was associated with financial reward and penalty, respectively. The magnitude of reward or penalty in each trial did not change; however, the subjects' self-reported emotional arousal was significantly higher for the events of "the fourth win of four wins in a row" and "the fourth loss of four losses in a row." We also found that the bilateral anterior cingulate and medial prefrontal cortices were specifically activated when the subjects experienced "the fourth win of four wins in a row" and "the fourth loss of four losses in a row." When the subjects experienced "a win following four losses in a row" or "a loss following four wins in a row," the right dorsolateral prefrontal cortex was specifically activated. Our data indicate that there exist brain activities associated with the event-sequence context in which abstract reward or penalty is received. These context-dependent activities appear to be crucial for adapting oneself to new circumstances and may account for clinical symptoms of various mental illnesses in which dysfunction of these regions has been reported.     

A case of an epithelioid glioblastoma with the BRAF V600E mutation colocalized with BRAF intact low‐grade diffuse astrocytoma

Epithelioid glioblastomas are one of the rarest histological variants of glioblastomas, which are not formally recognized by the World Health Organization (WHO) classification. Epithelioid glioblastomas usually occur as primary lesions, but there have been several reports of secondary epithelioid glioblastomas or epithelioid glioblastomas with pre‐ or co‐existing lesions to date. The serine/threonine‐protein kinase B‐Raf (BRAF) V600E mutation has been found at a high frequency of 54% in epithelioid glioblastomas. We present a case of a 26‐year‐old female patient with an epithelioid glioblastoma with the BRAF V600E mutation in her right frontal lobe. In the present case, a low‐grade diffuse astrocytoma component had colocalized with the epithelioid glioblastoma. The component presented prominent calcification on neuroimages as well as by histology, and low‐grade diffuse astrocytoma was considered to be a precursor lesion of an epithelioid glioblastoma. However, the BRAF V600E mutation was detected only in epithelioid glioblastoma but not in low‐grade diffuse astrocytoma. To the best of our knowledge, this is the first report demonstrating a discrepancy in the BRAF V600E mutation states between epithelioid glioblastoma and colocalized low‐grade astrocytoma.     

Clinicopathological and long-term prognostic features of membranous nephropathy with crescents: a Japanese single-center experience

Background

Three recent studies from the United States and China reported the clinicopathological features and short-term prognosis in patients with membranous nephropathy (MN) and crescents in the absence of secondary MN, anti-glomerular basement membrane (GBM) antibodies, and anti-neutrophil cytoplasmic antibodies (ANCA).

Methods

We compared clinicopathological and prognostic features in 16 MN patients with crescents (crescent group) and 38 MN patients without crescents (control group), in the absence of secondary MN, anti-GBM antibodies, and ANCA. Median follow-up periods in the crescent and control groups were 79 and 50 months, respectively.

Results

Decreased estimated glomerular filtration rates (<50 mL/min/1.73 m²), glomerulosclerosis, and moderate-to-severe interstitial fibrosis were more frequently observed in the crescent group than in the control group (P = 0.043, P = 0.004, and P = 0.035, respectively). Positive staining rates for glomerular IgG2 and IgG4 were significantly different between the 2 groups (P = 0.032, P = 0.006, respectively). Doubling of serum creatinine during follow-up was more frequently observed in the crescent group than in the control group (P = 0.002), although approximately two-thirds of patients in the crescent group were treated with immunosuppressive therapy. Crescent formation and interstitial fibrosis were risks for doubling of serum creatinine [hazard ratio (HR) = 10.506, P = 0.012; HR = 1.140, P = 0.009, respectively].

Conclusions

This is the first Japanese study demonstrating significant differences in clinicopathological and prognostic features between the 2 groups. Most patients in the crescent group may develop a long-term decline in renal function despite immunosuppressive therapy.

     

Mutation in human selenocysteine transfer RNA selectively disrupts selenoprotein synthesis

Selenium is a trace element that is essential for human health and is incorporated into more than 25 human selenocysteine-containing (Sec-containing) proteins via unique Sec-insertion machinery that includes a specific, nuclear genome–encoded, transfer RNA (tRNA^[Ser]Sec). Here, we have identified a human tRNA^[Ser]Sec mutation in a proband who presented with a variety of symptoms, including abdominal pain, fatigue, muscle weakness, and low plasma levels of selenium. This mutation resulted in a marked reduction in expression of stress-related, but not housekeeping, selenoproteins. Evaluation of primary cells from the homozygous proband and a heterozygous parent indicated that the observed deficit in stress-related selenoprotein production is likely mediated by reduced expression and diminished 2′-O-methylribosylation at uridine 34 in mutant tRNA^[Ser]Sec. Moreover, this methylribosylation defect was restored by cellular complementation with normal tRNA^[Ser]Sec. This study identifies a tRNA mutation that selectively impairs synthesis of stress-related selenoproteins and demonstrates the importance of tRNA modification for normal selenoprotein synthesis.