Primary renal synovial sarcoma: molecular and morphologic delineation of an entity previously included among embryonal sarcomas of the kidney.

We report 15 primary renal neoplasms with morphologic, immunohistochemical, and molecular features identical to those of synovial sarcoma. These tumors form a distinct subset of the entity previously designated as embryonal sarcoma of the kidney. Most were diagnosed between the ages of 20 and 50 years.

Metanephric stromal tumor: report of 31 cases of a distinctive pediatric renal neoplasm.

We report 31 cases of a novel pediatric renal neoplasm, metanephric stromal tumor (MST). Mean patient age was 2 years, and the most common presentation was that of an abdominal mass. Gross examination typically revealed a fibrous lesion centered in the renal medulla containing smooth-walled cysts (mean tumor size, 5.

A mutant hunt for defects in membrane protein assembly yields mutations affecting the bacterial signal recognition particle and Sec machinery.

We describe an Escherichia coli genetic screen that yields mutations affecting two different cellular processes: disulfide bond formation and membrane protein assembly. The mutants defective in disulfide bond formation include additional classes of dsbA and dsbB mutations. The membrane protein assembly defective mutants contain a mutation in the secA operon and three mutations in the ffs gene, which encodes 4.

Detection of the ETV6-NTRK3 chimeric RNA of infantile fibrosarcoma/cellular congenital mesoblastic nephroma in paraffin-embedded tissue: application to challenging pediatric renal stromal tumors.

We report the development of a reverse transcriptase polymerase chain reaction assay that reliably detects the ETV6-NTRK3 chimeric RNA characteristic of infantile fibrosarcoma and the cellular variant of congenital mesoblastic nephroma (CMN) in formalin-fixed, paraffin-embedded tissue blocks. The 188 base pair polymerase chain reaction fusion product was detected in 11 of 12 cases of cellular CMN from which a larger sized control RNA band could be amplified, and even in 7 of 8 cases in which the control band was not detectable. A variety of other tumors that are in the histologic differential diagnosis of cellular CMN yielded negative results, including four classic CMNs, four rhabdoid tumors of the kidney, and four clear cell sarcomas of the kidney, confirming the assay's specificity.

Thioredoxin 2 is involved in the oxidative stress response in Escherichia coli.

Two genes encoding thioredoxin are found on the Escherichia coli genome. Both of them are capable of reducing protein disulfide bonds in vivo and in vitro. The catalytic site contains a Cys-X(1)-X(2)-Cys motif in a so-called thioredoxin fold.

Towards single-copy gene expression systems making gene cloning physiologically relevant: lambda InCh, a simple Escherichia coli plasmid-chromosome shuttle system.

We describe a simple system for reversible, stable integration of plasmid-borne genes into the Escherichia coli chromosome. Most ordinary E. coli strains and a variety of pBR322-derived ampicillin-resistant plasmids can be used.

On the functional interchangeability, oxidant versus reductant, of members of the thioredoxin superfamily.

Escherichia coli thioredoxin 1 has been characterized in vivo and in vitro as one of the most efficient reductants of disulfide bonds. Nevertheless, under some conditions, thioredoxin 1 can also act in vivo as an oxidant, promoting formation of disulfide bonds in the cytoplasm (E. J.

Clear cell sarcoma of the kidney: a review of 351 cases from the National Wilms Tumor Study Group Pathology Center.

We reviewed 351 cases of clear cell sarcoma of the kidney (CCSK), including 182 cases entered on National Wilms Tumor Study Group (NWTSG) trials 1-4 for which clinical follow-up information was available. Tumors were restaged using NWTS 5 criteria. Mean age at diagnosis in the NWTS group was 36 months with a range of 2 months to 14 years.

Cell division in Escherichia coli: role of FtsL domains in septal localization, function, and oligomerization.

In Escherichia coli, nine essential cell division proteins are known to localize to the division septum. FtsL is a 13-kDa bitopic membrane protein with a short cytoplasmic N-terminal domain, a membrane-spanning segment, and a periplasmic domain that has a repeated heptad motif characteristic of leucine zippers. Here, we identify the requirements for FtsL septal localization and function.

Hemizygous deletions of chromosome band 16q24 in Wilms tumor: detection by fluorescence in situ hybridization.

Loss of heterozygosity (LOH) for markers on chromosome arm 16q in Wilms tumor has been linked to an increased risk of treatment failure. We therefore postulated that fluorescence in situ hybridization (FISH) with probes from this region might enhance current strategies for identifying high-risk patients at diagnosis. In a blinded comparative pilot study of 19 Wilms tumor samples from 18 patients with favorable histology, FISH and DNA polymorphism analysis yielded concordant results in 14 cases, either retention (n = 6) or loss (n = 8) of chromosome arm 16q markers.

Efficient folding of proteins with multiple disulfide bonds in the Escherichia coli cytoplasm.

Under physiological conditions, the Escherichia coli cytoplasm is maintained in a reduced state that strongly disfavors the formation of stable disulfide bonds in proteins. However, mutants in which the reduction of both thioredoxins and glutathione is impaired (trxB gor mutants) accumulate oxidized, enzymatically active alkaline phosphatase in the cytoplasm. These mutants grow very poorly in the absence of an exogenous reductant and accumulate extragenic suppressors at a high frequency.

Nuclear morphometry and prognosis in favorable histology Wilms' tumor: A prospective reevaluation.

Purpose: This study was designed to evaluate the ability of a previously published nuclear morphometry discriminant function to predict disease-free survival in patients with Wilms' tumor.

Patients And Methods: We identified 218 patients with stage I-IV Wilms' tumor of favorable histology who were entered onto the National Wilms' Tumor Study (NWTS) between January 1, 1990 and April 15, 1994. The nuclear morphometry score was calculated for each patient as follows: MV(f) = (0.

Six conserved cysteines of the membrane protein DsbD are required for the transfer of electrons from the cytoplasm to the periplasm of Escherichia coli.

The active-site cysteines of the Escherichia coli periplasmic protein disulfide bond isomerase (DsbC) are kept reduced by the cytoplasmic membrane protein, DsbD. DsbD, in turn, is reduced by cytoplasmic thioredoxin, indicating that DsbD transfers disulfidereducing potential from the cytoplasm to the periplasm. To understand the mechanism of this unusual mode of electron transfer, we have undertaken a genetic analysis of DsbD.

Importance of redox potential for the in vivo function of the cytoplasmic disulfide reductant thioredoxin from Escherichia coli.

The thioredoxin superfamily consists of enzymes that catalyze the reduction, formation, and isomerization of disulfide bonds and exert their activity through a redox active disulfide in a Cys-Xaa(1)-Xaa(2)-Cys motif. The individual members of the family differ strongly in their intrinsic redox potentials. However, the role of the different redox potentials for the in vivo function of these enzymes is essentially unknown.

National Wilms Tumor Study: an update for pathologists.

The National Wilms Tumor Study (NWTS)-5, begun in August 1995, incorporates some important new definitions and concepts that have critical importance in determining therapy and prognosis. The criteria for stage 1 were refined to accommodate an important subset of stage 1 Wilms tumors that are being managed by nephrectomy alone, without the use of adjuvant therapy. The distinction between stages 1 and 2 in the renal sinus is no longer defined by the hilar plane but by the presence or absence of venous or lymphatic invasion.

Oncocytoid renal cell carcinoma after neuroblastoma: a report of four cases of a distinct clinicopathologic entity.

Four children who developed oncocytoid renal cell carcinoma (RCC) after neuroblastoma are reported. One patient had multiple, bilateral RCCs. The mean age at time of diagnosis of RCC was 8.

Regulation of the OxyR transcription factor by hydrogen peroxide and the cellular thiol-disulfide status.

The Escherichia coli transcription factor OxyR is activated by the formation of an intramolecular disulfide bond and subsequently is deactivated by enzymatic reduction of the disulfide bond. Here we show that OxyR can be activated by two possible pathways. In mutants defective in the cellular disulfide-reducing systems, OxyR is constitutively activated by a change in the thiol-disulfide redox status in the absence of added oxidants.

Factors affecting the risk of contralateral Wilms tumor development: a report from the National Wilms Tumor Study Group.

Background: Approximately 1% of children with unilateral Wilms tumor develop contralateral disease. The authors assessed the demographic and histologic features associated with metachronous bilateral Wilms tumor (BWT).

Methods: Characteristics of all children registered on the first four National Wilms Tumor Studies (NWTS) were recorded.

Localization of FtsL to the Escherichia coli septal ring.

In Escherichia coli, nine gene products are known to be essential for assembly of the division septum. One of these, FtsL, is a bitopic membrane protein whose precise function is not understood. Here we use fluorescence microscopy to study the subcellular localization of FtsL, both in a wild-type strain and in a merodiploid strain that expresses a GFP-FtsL fusion protein.