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R E Weiss

Publications and source records attributed to R E Weiss.

At least 91 records · Page 5Linked to original sources
PubMed1993

Attention-deficit hyperactivity disorder and thyroid function.

Attention-deficit hyperactivity disorder (ADHD) is thought to have a biologic basis, but the precise cause is unknown. It is one of the neurodevelopmental abnormalities frequently observed in children with generalized resistance to thyroid hormone (GRTH), suggesting that thyroid abnormalities may be related to ADHD. We report a prospective screening study for thyroid abnormalities in 277 children with ADHD by measurement of serum levels of total thyroxine, free thyroxine index, and thyrotropin. Fourteen children with ADHD had thyroid function test abnormalities: six had a normal free thyroxine index and elevated thyroxine level (group 1); three had a high free thyroxine index and a normal thyrotropin level (group 2); and five had a low free thyroxine index with a normal thyrotropin level (group 3). GRTH could not be demonstrated in a detailed study of four of the subjects in whom it was suspected (groups 1 and 2). Although the prevalence of ADHD in subjects with GRTH has been reported to be 46%, the overall prevalence of GRTH must be less than 1:2500 because we failed to detect GRTH in the 277 children with ADHD studied. We conclude that the prevalence of thyroid abnormalities is higher (5.4%) in children with ADHD than in the normal population (< 1%).

Attention Deficit Disorder with Hyperactivity↗
PubMed1993

Covered exstrophy with sequestered colonic remnant.

We report on a woman who presented with urinary incontinence, covered exstrophy and an abdominal mass. Radiographic studies and cystoscopy confirmed that the anterior abdominal mass did not communicate with the bladder or colon and that the gastrointestinal tract was normal. Subsequent surgical resection of the mass and Young-Dees-Leadbetter bladder neck reconstruction were performed. Histological examination of the mass revealed colonic mucosa. The etiology of the covered exstrophy and sequestered colonic remnant is discussed.

Abnormalities, Multiple↗
PubMed1993

Isograft bladder mucosal transplantation for hypospadias repair in identical twins.

Urethral reconstruction with a bladder mucosal free graft offers several advantages for patients with complex hypospadias. We report a case in which identical twins circumcised at birth presented with mid-shaft hypospadias and chordee. A bladder mucosa graft was harvested from 1 twin, divided and used to form 2 neourethras. The donor twin underwent hypospadias repair, followed immediately by repair in the second twin with the isograft neourethra. To our knowledge this is the first reported case of bladder mucosal transplantation for hypospadias repair.

Child, Preschool↗
PubMed1993

Metastatic renal cell carcinoma presenting as impotence.

We describe a patient who initially presented with impotence followed by progressive lethargy and visual disturbances. Endocrine and radiological evaluation was suggestive of pituitary adenoma but pathological evaluation after transsphenoidal hypophysectomy revealed renal cell carcinoma metastatic to the pituitary. The etiology of this unusual presentation and prior reports of renal cell carcinoma spread to the pituitary are reviewed.

Carcinoma, Renal Cell↗
PubMed1993

Identical mutations in unrelated families with generalized resistance to thyroid hormone occur in cytosine-guanine-rich areas of the thyroid hormone receptor beta gene. Analysis of 15 families.

Generalized resistance to thyroid hormone (GRTH) is a syndrome of variable reduction of tissue responsiveness to thyroid hormone. 28 different point mutations in the human thyroid hormone receptor beta (TR beta) gene have been associated with GRTH. These mutations are clustered in two regions of the T3 binding domain of the TR beta (codons 310-347 and 417-453). We now report point mutations in the TR beta gene of six additional families with GRTH and show that three mutations occurred each in three families with GRTH, and that three other mutations were each present in two families. In 11 of these 15 families, lack of a common ancestor could be confirmed by genetic analysis. 28 of the 38 point mutations so far identified, including all those occurring in more than one family, are located in cytosine-guanine-rich areas of the TR beta gene. Differences in clinical and laboratory findings in unrelated families harboring the same TR beta mutation suggest that genetic variability of other factors modulate the expression of thyroid hormone action.

Base Composition↗
PubMed1993

Multiple genetic factors in the heterogeneity of thyroid hormone resistance.

Generalized resistance to thyroid hormone (GRTH), a syndrome of inherited tissue hyposensitivity to thyroid hormone, is linked to thyroid hormone receptor (TR) mutations. A typical feature of GRTH is variable severity of organ involvement among families that, surprisingly, does not correlate with the degree of T3-binding impairment of the corresponding in vitro synthesized mutant TRs. Furthermore, variations in the clinical severity among family members harboring identical TR beta mutations have been reported. We compared serum levels of thyroid hormones that maintained a normal TSH in members of a large family with GRTH divided in three groups: Group A, 8 affected subjects with a mutation replacing arginine-320 with a histidine in the T3-binding domain of TR beta; Group B, 11 first degree relatives (sibs and children of affected subjects) with no TR beta mutation; Group C, 16 controls related by marriage. TSH values were not different among the three groups. As expected, total and free T4 and T3, and rT3 levels were significantly higher in Group A vs Groups B and C. However, with the exception of T3, the same tests were also significantly higher in Group B vs Group C. The latter differences are not due to thyroid hormone transport in serum since TBG concentrations were not different. It is postulated that genetic variability of factors that contribute to the action of thyroid hormone modulate the phenotype of GRTH associated with TR beta mutations.

Adult↗
PubMed1993

The relative expression of mutant and normal thyroid hormone receptor genes in patients with generalized resistance to thyroid hormone determined by estimation of their specific messenger ribonucleic acid products.

Generalized resistance to thyroid hormone (GRTH), is a syndrome of reduced tissue responsiveness to thyroid hormone. So far, mutations linked to GRTH have been only detected in the hormone-binding domain of the human thyroid hormone receptor (hTR)-beta gene. Although there is no doubt that these mutations result in abnormal hTRs, there is a conspicuous lack of correlation between the severity of clinical manifestations and the degree of functional impairment of the mutant hTRs. In this work we examined whether variable expression of mutant genes relative to the normal genes could explain the observed discrepancies. The relative amounts of mutant and normal hTR beta and normal hTR alpha messenger RNAs in fibroblasts from normal subjects and those from individuals with GRTH were estimated by coamplification of their complementary DNA products. Heterozygous subjects with GRTH from two families manifesting differences in the severity of clinical manifestations expressed equally both normal and mutant hTR beta alleles. Furthermore, there was no compensatory increase in the expression of the normal hTR alpha gene in these individuals nor in fibroblasts from members of a third family with homozygous deletion of the hTR beta gene. In vitro treatment with thyroid hormone did not affect the results. It is concluded that the apparent discrepancies between the functional impairment of the mutant hTRs and the clinical manifestations of GRTH are not due to quantitative differences in the expression of the normal or mutant hTR genes but more likely to variations in the interactions of the mutant hTRs with the normal hTR beta, hTR alpha and nuclear stabilization factors.

Alleles↗
PubMed1993

Human thyroxine-binding globulin gene: complete sequence and transcriptional regulation.

T4-binding globulin (TBG) is a glycoprotein of hepatic origin which transports thyroid hormone in serum. To characterize the human TBG (hTBG) gene, we studied its genomic organization, promoter activity, and regulation. To this purpose, we isolated from liver a complete hTBG cDNA clone containing the 5'-untranslated region and localized the transcription start site (TSS). The analysis of genomic clones revealed that the hTBG gene consists of five exons and that its exon-intron organization is similar to that of other members of the serine protease inhibitor family. The first exon (exon 0) is a short noncoding sequence located 1.62 kilobase pairs (kbp) upstream from exon 1. Potential cis-acting transcriptional regulatory elements including a TATA box, a CAAT box, and a hepatocyte nuclear factor-1 binding motif were identified in the upstream region. A reporter gene in which 3.2 kbp of the 5'-flanking region, including exon 0, was inserted upstream of the bacterial chloramphenicol acetyltransferase gene showed significant activity when transfected into a hepatblastoma-derived (HepG2) cell line. The phorbol ester, 12-O-tetradecanoylphorbol-13-acetate, down-regulated the promoter activity by more than 80% and completely inhibited hTBG synthesis, whereas thyroid hormone, glucocorticoid, estrogen, and nicotinic acid had little, if any, effect. A series of 5'-deletions revealed that the fragment -218 to +4 from the TSS had the highest promoter activity, nearly 1000-fold greater than the promoterless chloramphenicol acetyltransferase construct. When nonhepatocyte-derived cell lines (CV-1 and CHO) were tested, promoter activity was reduced by a factor of 100, showing that the promoter works in liver-specific manner. The region -218 to -102 contains liver-specific enhancer elements, since deletion to nucleotide -101 resulted in a profound reduction of the promoter activity in HepG2 cells but not in CV-1 or CHO cells. On the other hand, mutational disruption of the putative hepatocyte nuclear factor-1 site (located 65 bp upstream of the TSS) completely abolished the promoter activity in all cell lines, indicating that this site is absolutely required for the transcription of the hTBG gene.

Amino Acid Sequence↗
PubMed1992

Abrogation of the invasion of human bladder tumor cells by using protease inhibitor(s).

It was shown previously that invasive human transitional cell carcinoma cell line EJ, but not the noninvasive RT4 cells, can degrade basement membrane laminin and that the degradation of basement membrane laminin was a result of a redistribution of activated cysteine proteinase cathepsin B to the plasma membrane of the invasive EJ cells. Using a modified Boyden chamber and an artificial basement membrane, it was found first that cysteine proteinase inhibitor E-64 can abolish the ability of the EJ cells to invade through the artificial basement membrane to the underside of the filter. Second, E-64 can prevent the degradation of purified human basement membrane laminin by the plasma membrane fraction of invasive EJ cells. Third, E-64 does not affect the ability of the EJ cells to attach to the extracellular matrix nor is the inhibitory dose toxic to the cells when assayed with trypan-blue dye exclusion. However, E-64 does affect the ability of the EJ cells to respond to autocrine motility factor-induced motility. Finally, in an in vivo model, E-64 was not toxic to the animals tested and may have limited the blood-borne metastatic ability of invasive EJ cells in the treated animals. It was concluded that proteinase cathepsin B may be involved in human bladder tumor invasion, in both extracellular matrix degradation and factor-induced cellular motility, and the authors suggested that the use of inhibitor(s) to cysteine proteinases may limit the invasive potential of human bladder cancer cells.

Animals↗
PubMed1992

Residual plots for repeated measures.

Multivariate data are difficult to analyse partly because of difficulty in looking at the data. Repeated measures data have a special structure that makes the parallel plot particularly effective for viewing the data. In this paper we use parallel plots to display not just raw data but also residuals from standard models fit to repeated measures data. The plots are useful for determining how well a particular model fits the data, identifying outlying observations and suggesting terms missing from the linear predictor.

Adolescent↗
PubMed1992

Bacillus Calmette-Guerin abrogates in vitro invasion and motility of human bladder tumor cells via fibronectin interaction.

Intravesical bacillus Calmette-Guerin (BCG) has been shown to be an effective treatment for superficial transitional cell carcinoma of the bladder (TCC). The mechanisms by which BCG limits tumor cell activity have thus far been unclear. We investigated the interaction between BCG and invasive human TCC cell line EJ in an in vitro invasion assay. We observed that BCG inhibited the invasion of EJ cells through an artificial basement membrane. In terms of the steps involved in tumor cell invasion, i.e. attachment, proteolysis, and motility, BCG was found to limit tumor cell motility. Attachment and proliferation of tumor cells were not affected by BCG. The effects of BCG on tumor cell migration were mediated by fibronectin (FN), a basement membrane glycoprotein component. Abrogation of BCG-FN-tumor cell interactions with anti-FN antibodies eliminated the ability of BCG to block tumor cell invasion. Fibronectin appears to link BCG and tumor cells via independent FN binding receptors to separate domains of the FN molecule. The molecular mechanism by which BCG may limit tumor cell motility may be its ability to protect against the formation of specific FN sequences as a result of protease cathepsin B digestion. A 31 kD and 27 kD FN band were absent from purified or tumor cell associated cathepsin B digestion when incubated in the presence of BCG, but present in the absence of BCG. Furthermore when purified from SDS polyacrylamide gel electrophoresis, the fragments were shown to have motility stimulating activity for the invasive EJ cells. These findings suggest that BCG functions as a potent inhibitor of tumor cell invasion. We conclude that BCG-fibronectin-tumor cell interactions may have a direct influence on the invasive mechanisms, such as motility, of tumor cells.

BCG Vaccine↗
PubMed1992

Thyroid hormone resistance.

Generalized resistance to thyroid hormone (GRTH) encompasses a heterogeneous group of conditions characterized by reduced responses of target tissues to thyroid hormone due to defects at the site of hormone action. In the majority of patients, GRTH is inherited as a dominant trait associated with mutations in the hormone-binding domain of the thyroid hormone receptor. GRTH serves as a prototype of other resistance syndromes for hormones that act via nuclear receptors.

Diagnosis, Differential↗
PubMed1992

Rapid localization of mutations in the thyroid hormone receptor-beta gene by denaturing gradient gel electrophoresis in 18 families with thyroid hormone resistance.

Generalized resistance to thyroid hormone (GRTH) is an inherited syndrome of reduced tissue responsiveness to thyroid hormone. Point mutations in the human thyroid hormone receptor-beta (hTR beta) gene of these patients, causing single amino acid substitutions, appear be different in unrelated individuals affected by the same syndrome. To localize mutations in the hTR beta gene, GC-clamped DNA fragments from affected individuals belonging to 21 families with GRTH were generated by the polymerase chain reaction and analyzed by denaturing gradient gel electrophoresis (DGGE). Putative mutations in the hTR beta gene of 18 unrelated individuals with GRTH were identified, and their nature has been confirmed in 9 by sequencing. All were in the hormone-binding domain of the receptor, and 13 of 18 mutations were in its center (exon 7). In 3 families we were unable to identify mutations in hTR beta, suggesting the existence of mutations at other loci, possibly the hTR alpha gene or other proteins involved in the thyroid hormone-dependent transactivation system. Sequencing of DNA fragments negative for the presence of putative mutations by DEEG confirmed the absence of sequence differences. DGGE of amplified DNA fragments can rapidly and reliably localize the sites of mutations in the hTR beta gene of patients with GRTH. The procedure enabled mapping the regions in the hTR beta harboring mutations associated with GRTH.

Base Sequence↗
PubMed1991

Sodium currents during differentiation in a human neuroblastoma cell line.

The electrophysiological properties of a human neuroblastoma cell line, LA-N-5, were studied with the whole-cell configuration of the patch clamp technique before and after the induction of differentiation by retinoic acid, a vitamin A metabolite. Action potentials could be elicited from current clamped cells before the induction of differentiation, suggesting that some neuroblasts of the developing sympathetic nervous system are excitable. The action potential upstroke was carried by a sodium conductance, which was composed of two types of sodium currents, described by their sensitivity to tetrodotoxin (TTX) as TTX sensitive and TTX resistant. TTX-sensitive and TTX-resistant sodium currents were blocked by nanomolar and micromolar concentrations of TTX, respectively. The voltage sensitivity of activation and inactivation of TTX-resistant sodium current is shifted -10 to -30 mV relative to TTX-sensitive sodium current, suggesting that TTX-resistant sodium current could play a role in the initiation of action potentials. TTX-sensitive current comprised greater than 80% of the total sodium current in undifferentiated LA-N-5 cells. The surface density of total sodium current increased from 24.9 to 57.8 microA/microF after cells were induced to differentiate. The increase in total sodium current density was significant (P less than 0.05). The surface density of TTX-resistant sodium current did not change significantly during differentiation, from which we conclude that an increase in TTX-sensitive sodium current underlies the increase in total current.

Cell Differentiation↗
PubMed1991

Sodium current and membrane potential in EDL muscle fibers from normal and dystrophic (mdx) mice.

The macroscopic and single-channel properties of sodium currents and membrane potential were studied in intact extensor digitorum longus (EDL) muscle fibers from mdx (C57BL/10ScSn-mdx) and normal (C57BL/10SnJ) mice. The voltage dependence of activation and inactivation were determined and the associated gating charges were calculated to determine if the lack of dystrophin associated with the mdx condition has any influence on sodium channels either directly or by effects on the membrane environment of the channel. Sodium currents were recorded from cell-attached patches on EDL muscle fibers isolated by collagenase treatment and manual dissection. Both macroscopic and single-channel currents were studied. We found no apparent difference in the sodium channel properties from the two types of muscle. In addition, microelectrode measurements in both mdx and normal muscle fibers indicated similar resting membrane potentials (Vm around -95 mV), which suggests that the normal behavior of sodium channels in the muscle sarcolemma is unaffected by the X-linked gene defect.

Animals↗
PubMed1990

Neonatal detection of generalized resistance to thyroid hormone.

Generalized resistance to thyroid hormone (GRTH) is an inherited disease that is usually suspected when elevated serum thyroid hormone levels are associated with nonsuppressed thyrotropin. Often these test results are obtained because of short stature, decreased intelligence, and/or hyperactivity with learning disability noted in childhood and adolescence, or because of goiter in adulthood. We detected GRTH at birth by analysis of blood obtained during routine neonatal screening. The proposita, born to a mother with GRTH, had a thyrotropin level of 26 mU/L and a corresponding thyroxine concentration of 656 nmol/L (normal, 84 to 232 nmol/L). Administration of thyroid hormone in doses eightfold to 10-fold above replacement levels (liothyronine sodium, 21 micrograms/kg per day, and levothyroxine sodium, 44 micrograms/kg per day) were required to reduce serum thyrotropin to normal levels without induction of hypermetabolism. This case, and the retrospective finding of high thyroxine levels in five newborns subsequently diagnosed as having GRTH, suggest that measurement of thyroxine at birth, in conjunction with thyrotropin, could allow the early detection of GRTH.

Basal Metabolism↗