Adult ADHD and AIDS.
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Biomedical subjects
Publications and source records attributed to R E Weiss.
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Familial dysalbuminemic hyperthyroxinemia (FDH) is the most common cause of inherited euthyroid hyperthyroxinemia in Caucasians. Transmitted as an autosomal dominant trait, it is always associated with high serum total T4 (TT4) and more rarely with elevated total T3 (TT3) and/or rT3 (TrT3) concentrations. Free T4, by dialysis, and TSH levels are normal, suggesting the presence of a T4-binding protein abnormality. The abnormal serum T4 carrier shares some physical and immunological properties with albumin, suggesting that it may be albumin itself. Here we show linkage between FDH and the albumin gene in a large Amish family of Swiss descent, using as markers a SacI polymorphism in the coding sequence of the albumin gene and the group-specific component (Gc) gene, located less than 1 centimorgan from the albumin gene. Blood samples were obtained from 160 members of this kindred, and 22 had FDH identified by the pattern of T4 binding to serum proteins separated by isoelectric focusing. Serum TT4 values were above the normal range in all subjects expressing the FDH phenotype, and TrT3 levels were above the normal range in only one half. TT4 concentrations correlated positively with TrT3 and TT3. All TT3 values were, however, within the normal range. Free T4 and TSH levels were normal, confirming the euthyroid state in these subjects. FDH was associated with the albumin SacI(+)/Gc 1S haplotype, yielding a LOD (logarithm of the odds ratio) score of 5.53, with a recombination frequency of 0. These data provide strong support that a variant albumin is the cause of FDH in this kindred.
Resistance to thyroid hormone (RTH), a syndrome characterized by variable tissue hyposensitivity to thyroid hormone, is linked to mutations in the thyroid hormone receptor-beta (TR beta) gene. The purpose of this study was to determine whether the clinical phenotypes of RTH can be translated in terms of functional impairment of the corresponding mutant TR beta. Data from 124 subjects with RTH representing 18 different mutant TR beta s, showed that serum free T4 levels correlated with the degree of T3-binding impairment of the corresponding TR beta in 12 of these mutant TR beta s (group I), but not in the remaining 6 (group II). In subjects from both groups studied in detail by the administration of incremental doses of T3, the degree of thyrotroph resistance to T3 correlated with the magnitude of endogenous free T4 elevation at baseline, but did not parallel the resistance of peripheral tissues. In transfection studies, all group I mutant TR beta s inhibited positive transactivation by the wild type TR beta s to a similar degree in the presence of 1 nmol/L T3, whereas group II mutant TR beta s exerted a weaker inhibition that was not related to their T3-dependent trans-activation when tested alone. Similar results were obtained with negatively regulated reporter genes. It is concluded that the clinical severity of RTH, determined by thyrotroph resistance, can be predicted from the degree of T3 binding impairment and dominant negative potency of mutant TR beta s, but the degree of peripheral tissue resistance and related clinical manifestations is limited by putative genetic or environmental factors that modulate the effect of thyroid hormone.
Familial dysalbuminemic hyperthyroxinemia (FDH) is the most common form of inherited increase of serum thyroxine in Caucasians. It is the result of increased thyroxine-binding to serum proteins and is inherited as a dominant trait. The entire coding region of the albumin gene of a subject with FDH was sequenced. A single nucleotide substitution, G to A transition in codon 218, was found in one of the two alleles, resulting in the replacement of the normal Arg with His. This mutation was found in 9 affected family members but not in 8 unaffected relatives and 18 unrelated normal individuals. The same missense mutation was found in 12 other subjects with FDH belonging to 7 unrelated families. In every individual with FDH, the mutation was associated with the Sac I+ polymorphism in the albumin gene, strongly suggesting a founder effect.
Pregnancy presents a wide range of difficult urological management problems. We report a unique case of a term intra-abdominal pregnancy complicated by persistent hydronephrosis after cesarean section. Intra-abdominal placenta degeneration was monitored by serial serum beta-human chorionic gonadotropin values. Hydronephrosis ultimately resolved with conservative management.
Resistance to thyroid hormone (RTH) is a condition of impaired tissue responsiveness to thyroid hormone characterized by elevated free thyroid hormone levels in serum accompanied by nonsuppressed TSH. RTH has been associated with mutations in the thyroid hormone receptor (TR) beta gene. We report studies carried out in 9 members of a family (F94) of Jewish ethnic origin and a single subject of Mexican origin. All subjects fulfilling the criteria of RTH (6 of family F94 and one of family F27) had the same point mutation in the T3-binding domain on one of the two alleles of the TR beta gene. This mutation resulted in the replacement of the normal proline-453 with serine (P453S). Nevertheless, the clinical characteristics of affected members of each of the two families differed as did the severity of hormonal resistance in terms of responses to the administration of L-T3. Genetic studies indicate that the same mutation occurred independently in each of the two families.
Resistance to thyroid hormone (RTH) is a condition of impaired end-organ responsiveness to thyroid hormone characterized by goiter and elevated thyroid hormone levels with an inappropriately normal TSH. RTH has been associated with mutations in the thyroid hormone receptor-beta (TR beta) gene. We report studies carried out in 21 members of a family (F119), 12 of whom exhibited the RTH phenotype. A point mutation was detected in the T3-binding domain of the TR beta gene. It resulted in replacement of the normal cysteine-446 with an arginine (C446R) that has not been previously reported. The clinical characteristics of this family are similar to those reported in other families with RTH, namely goiter, tachycardia, and learning disabilities. Thyroid function tests are also typical of other subjects with RTH. The mean values (+/- SD) in untreated affected subjects compared to those in unaffected family members were: free T4 index, 250 +/- 21 vs. 108 +/- 13; total T3, 4.3 +/- 0.4 vs. 2.4 +/- 0.4 nmol/L; and TSH, 4.5 +/- 1.1 vs. 2.4 +/- 1.1 mU/L. DNA samples from 18 family members were screened for the TR beta mutation, which results in the loss of a BsmI restriction site, and each of the 11 subjects with abnormal thyroid function tests were heterozygous for the mutant allele. The mutant TR beta expressed in Cos-I cells did not bind T3 (Ka of C446R/wild-type, < 0.05). T3 at a concentration up to 100 nmol/L failed to enhance the transactivation of a reporter gene, and the mutant receptor inhibited the T3-mediated transcriptional activation of the wild-type TR beta.
Resistance to thyroid hormone (RTH) is a syndrome of reduced responsiveness of tissues to thyroid hormone. The clinical manifestations are variable and 46-50% of children with RTH have attention deficit hyperactivity disorder (ADD). We present a new family with RTH (F120) found to have a mutation R316H in the thyroid hormone receptor beta (TR beta) gene identical for that reported in an unrelated family. Assignment of the mutant allele and haplotyping based on CA repeat polymorphism were done on 16 family members. Semistructured diagnostic interviews and psychometric testing were used to determine the psychiatric diagnosis of 12 family members by examiners blinded to the genotype. Three subjects were identified to have the R316H allele as well as mildly elevated free T4 index (168 +/- 12; normal range 77-135) and nonsuppressed TSH (4.1 +/- 1.7 mU/L). Only 2 of the subjects with RTH were found to have ADD, while one family member homozygous for the wild type TR beta and normal thyroid function tests also had ADD. Unaffected family members had higher full scale intelligence quotients (IQ) (93 +/- 7) than any of the 3 family members with RTH (77 +/- 5, p = 0.006). These data do not support the genetic linkage of ADD and RTH, but do suggest that RTH is associated with lower IQ scores that may confer a high likelihood of exhibiting ADD symptoms.
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%).
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.
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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.
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.
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.
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.
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.
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.
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