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J Seidman

Publications and source records attributed to J Seidman.

At least 19 recordsLinked to original sources
PubMed2005

Compound and double mutations in patients with hypertrophic cardiomyopathy: implications for genetic testing and counselling.

OBJECTIVE: To report the frequency of single and multiple gene mutations in an Australian cohort of patients with hypertrophic cardiomyopathy (HCM). METHODS: Genetic screening of seven HCM genes (beta-MHC, MyBP-C, cTnT, cTnI, ACTC, MYL2, and MYL3) was undertaken in 80 unrelated probands. Screening was by denaturing high performance liquid chromatography and direct DNA sequencing. Clinical data were collected on all patients and on genotyped family members. RESULTS: 26 mutations were identified in 23 families (29%). Nineteen probands (24%) had single mutations (11 beta-MHC, 4 MyBP-C, 3 cTnI, 1 cTnT). Multiple gene mutations were identified in four probands (5%): one had a double mutation and the others had compound mutations. Six of 14 affected individuals from multiple mutation families (43%) experienced a sudden cardiac death event, compared with 10 of 55 affected members (18%) from single mutation families (p = 0.05). There was an increase in septal wall thickness in patients with compound mutations (mean (SD): 30.7 (3.1) v 24.4 (7.4) mm; p<0.05). CONCLUSIONS: Multiple gene mutations occurring in HCM families may result in a more severe clinical phenotype because of a "double dose" effect. This highlights the importance of screening the entire panel of HCM genes even after a single mutation has been identified.

Adolescent↗
PubMed2004

Clinical and genetic linkage analysis of a large Venezuelan kindred with Usher syndrome.

OBJECTIVE: To undertake a comprehensive investigation into the very high incidence of congenital deafness on the Macano peninsula of Margarita Island, Venezuela. METHODS: Numerous visits were made to the isolated island community over a 4-year-period. During these visits, it became apparent that a significant number of individuals complained of problems with hearing and vision. Socioeconomic assessments, family pedigrees and clinical histories were recorded on standard questionnaires. All individuals underwent thorough otolaryngologic and ophthalmologic examinations. Twenty milliliters of peripheral venous blood was obtained from each participant. A genome-wide linkage analysis study was performed. Polymorphic microsatellite markers were amplified by polymerase chain reaction and separated on polyacrylamide gels. An ABI 377XL sequencer was used to separate fragments and LOD scores were calculated by using published software. RESULTS: Twenty-four families were identified, comprising 329 individuals, age range 1-80 years, including 184 children. All families were categorized in the lower two (least affluent) socioeconomic categories. A high incidence of consanguinity was detected. Fifteen individuals (11 adults, 4 children) had profound congenital sensorineural hearing loss, vestibular areflexia and retinitis pigmentosa. A maximum LOD score of 6.76 (Linkage >3.0), between markers D11s4186 and D11s911, confirmed linkage to chromosome 11q13.5. The gene myosin VIIA (MYO7A) was confirmed in the interval. Clinical and genetic findings are consistent with a diagnosis of Usher syndrome 1B for those with hearing and vision problems. CONCLUSIONS: We report 15 Usher syndrome 1B individuals from a newly detected Latin American socio-demographic origin, with a very high prevalence of 76 per 100,000 population.

Adolescent↗
PubMed2001

Abnormal fragile histidine triad (FHIT) expression in advanced cervical carcinoma: a poor prognostic factor.

The FHIT gene is a candidate tumor suppressor gene that has been implicated in the development of cervical carcinoma. We hypothesized that abnormal Fhit expression might be a poor prognostic factor for patients with cervical cancer. The tumors from 59 high-risk patients (stage II-III) were evaluated for abnormal Fhit expression by immunohistochemical staining. Abnormal Fhit expression (absent or reduced) was noted in 66% of the specimens. There was no statistical difference with respect to stage, performance status, para-aortic node metastasis, completion of therapy, grade, race, age, and HIV status between the normal and abnormal Fhit expression groups. The 3-year survival for patients whose tumors displayed normal Fhit expression versus abnormal Fhit expression was 74% versus 37%, respectively. Univariate analysis demonstrated a difference in survival that was statistically significant for age <55 years versus > or =55 years (P = 0.015), normal Fhit expression versus abnormal Fhit expression (P = 0.015), and stage II versus stage III (P = 0.033). Multivariate analysis showed that abnormal Fhit expression was a poor prognostic factor (P = 0.015).

Acid Anhydride Hydrolases↗
PubMed2001

Malakoplakia involving the abdominal wall, urinary bladder, vagina, and vulva: case report and discussion of malakoplakia-associated bacteria.

A 29-year-old woman presented with a 3-month history of multiple purulent discharging nodules involving her lower abdomen, vulva, and left thigh. Physical examination also disclosed vaginal nodules and a left pelvic mass. Cystoscopy revealed multiple mucosal nodules and a perforation of the left vesical wall that appeared to communicate with the pelvic mass. Biopsies of the vesical and vulvar nodules revealed malakoplakia. Surgery and antibiotic therapy resulted in regression of all the lesions.

Abdominal Muscles↗
PubMed2000

Clinical goals and performance measures for cholesterol management in secondary prevention of coronary heart disease.

Guidelines from the National Cholesterol Education Program (NCEP) recommend reduction of low-density lipoprotein cholesterol (LDL-C) to 100 mg/dL (2.59 mmol/L) or less in patients with established coronary heart disease (CHD). However, the National Committee for Quality Assurance (NCQA) is implementing a new performance measure as part of the Health Plan Employer and Data Information Set (HEDIS) that appears to endorse a different target. The new HEDIS measure will require managed care organizations seeking NCQA accreditation to measure and report the percentage of patients who have had major CHD events who achieve LDL-C levels less than 130 mg/dL (3.36 mmol/L) between 60 and 365 days after discharge. These different LDL-C thresholds emphasize the difference between a clinical goal for the management of individual patients (< or =100 mg/dL) and a performance measure used to evaluate the care of a population of patients (<130 mg/dL). This article discusses the rationale for each threshold and explains the use of 2 different thresholds for these 2 purposes. Both the NCQA and NCEP expect that the new HEDIS measure will encourage managed care organizations to develop systems that improve secondary prevention of CHD.

Adult↗
PubMed1999

A selective role of calcineurin aalpha in synaptic depotentiation in hippocampus.

Pharmacological studies have suggested that long-term potentiation (LTP) and long-term depression (LTD) and depotentiation, three forms of synaptic plasticity in the hippocampus, require the activity of the phosphatase calcineurin. At least two different isoforms of calcineurin are found in the central nervous system. To investigate whether all of these forms of synaptic plasticity require the same isoforms of calcineurin, we have examined LTD, depotentiation, and LTP in mice lacking the predominant calcineurin isoform in the central nervous system, Aalpha-/- mice. Depotentiation was abolished completely whereas neither LTD nor LTP were affected. These studies provide genetic evidence that the Aalpha isoform of calcineurin is important for the reversal of LTP in the hippocampus and indicate that depotentiation and LTD operate through somewhat different molecular mechanisms.

Animals↗
PubMed1999

Long-term follow-up of chimpanzees inoculated with the first infectious clone for hepatitis C virus.

Two chimpanzees (Ch1535 and Ch1536) became infected with hepatitis C virus (HCV) following intrahepatic inoculation with RNA transcribed from a full-length cDNA clone of the virus. Both animals were persistently infected and have been followed for 60 weeks. They showed similar responses to infection, with transient liver enzyme elevations and liver inflammatory responses, which peaked at weeks 17 (Ch1535) and 12 (Ch1536) postinoculation (p.i.). Antibody responses to structural and nonstructural proteins were first detected at weeks 13 (Ch1535) and 10 (Ch1536) p.i. Serum RNA titers increased steadily during the first 10 to 13 weeks but decreased sharply in both animals following antibody and inflammatory responses. Despite direct evidence of humoral immune responses to multiple viral antigens, including hypervariable region 1 (HVR1), both animals remained chronically infected. Detailed sequence analysis of serum HCV RNA revealed no change in the majority HVR1 sequence in Ch1535 and a single-amino-acid mutation in Ch1536, with very little clonal variation in either animal. Full-length genome analysis at week 60 revealed several amino acid substitutions localized to antigens E1, E2, p7, NS3, and NS5. Of these, 55.6 and 40% were present as the majority sequence in serum RNA isolated at week 26 p.i. (Ch1535) and week 22 p.i. (Ch1536), respectively, and could represent immune escape mutations. Mutations accumulated at a rate of 1.57 x 10(-3) and 1.48 x 10(-3) nucleotide substitutions/site/year for Ch1535 and Ch1536, respectively. Taken together, these data indicate that establishment of a persistent HCV infection in these chimpanzees is not due to changes in HVR1; however, the possibility remains that mutations arising in other parts of the genome contributed to this persistence.

Amino Acid Sequence↗
PubMed1994

Assignment of a locus for dominantly inherited venous malformations to chromosome 9p.

Venous malformation is the most common type of vascular anomaly. Depending upon size and location, these slow-flow anomalies may cause pain, anatomic distortion, or threaten life. Most venous malformations occur sporadically and present as solitary lesions. They also occur in several syndromes, some of which demonstrate Mendelian inheritance. We have mapped the locus for an autosomal dominant disorder in a three generation family that manifests as multiple cutaneous and mucosal venous malformations. This locus lies within a 24 cM interval on chromosome 9p, defined by the markers D9S157 and D9S163. The alpha and beta interferon gene cluster and the putative tumor suppressor genes MTS1 and MTS2 are also in this region. Characterization of the gene responsible for this disorder should yield insights into the precise pathogenic mechanisms for venous malformations.

Abnormalities, Multiple↗
PubMed1994

Cold compressive dressing after total knee arthroplasty.

The efficacy of a cold compressive dressing after total knee arthroplasty (TKA) was prospectively studied in 105 knees in 76 patients. All components were cemented. All patients were placed in continuous passive motion machines after operation. A cold compressive Cryocuff dressing was applied to 50 knees after operation. An ACE wrap and ice pack were applied to the knees of 55 control patients after operation. Postoperative range of motion was recorded as maximum active flexion at two to four days (interval one), at seven to 14 days (interval two), and four to six weeks (interval three). Swelling was measured at the same time intervals by circumference at the midpatella and circumference at the distal thigh one inch proximal to the superior pole of the patella. Use of postoperative narcotics was calculated for postoperative days zero to three and for postoperative days four to seven. Wound drainage was recorded for all knees. The use of a cold compressive dressing after TKA was not associated with an increase in range of motion at any point after the operation. The Cryocuff dressing did not appreciably reduce swelling around the knee after TKA. No significant difference was found in the amount of postoperative wound drainage between the two groups of patients. In patients undergoing unilateral TKA, no significant difference existed between the narcotic requirements of control patients and patients wearing the cold compressive dressing.

Analgesics, Opioid↗
PubMed1991

Pathobiology of the human A1 pulley in trigger finger.

Eighty-nine A1 pulleys from 65 patients with trigger digits and 20 control A1 pulleys from fresh-frozen cadavers were studied comparatively with histology, immunohistochemistry, and transmission electron microscopy. In both normal and pathologic specimens, the A1 pulley was composed of two layers: an outer, vascularized, convex layer and an inner, concave, friction, flexor tendon gliding layer. In the latter, the cells and adjacent matrix had several characteristics of fibrocartilage, including chondrocytes. In trigger digits, the number of chondrocytes and adjacent extracellular matrix was significantly increased when compared with controls. There was no evidence of a synovial cell layer on the surface of the A1 pulleys in either normal or trigger digits. We conclude that the underlying pathobiological mechanism for triggering at the A1 pulley is characterized by a fibrocartilage metaplasia.

Female↗
PubMed1987

Provocative pattern of rearrangements of the genes for the gamma and beta chains of the T-cell receptor in human leukemias.

To examine the distribution of rearrangements of the gamma- and beta-chain T-cell receptor (TCR) genes in T- and non-T acute lymphoblastic leukemias (ALLs), and potentially to determine which genes rearrange first in ontogeny, we analyzed high molecular weight DNA from 102 patients with acute leukemia. Rearranged gamma- and beta-chain genes were found in all T-cell ALLs (22/22) examined. Overall, 27% (18/66) of B-lineage ALLs had beta-chain gene rearrangements, and 41% (24/58) had gamma-chain gene rearrangements, but the distribution of rearranged genes varied according to the stage of B-cell differentiation. The gamma-chain genes were rearranged in 11% (1/9) of the B-lineage patients negative for the common acute lymphoblastic leukemia antigen (cALLA) and 50% (23/46) of cALLA+ ALL patients, while the beta-chain genes were not rearranged in any of the 7 cALLA- ALL patients examined but were rearranged in 32% (18/56) of the cALLA+ patients. Neither TCR gene was found to be rearranged in acute nonlymphoid leukemia patients (0/12) or in patients with B-cell (surface immunoglobulin-positive) leukemia (0/3). Of the 44 cALLA+ patients in which a direct comparison of gamma- and beta-chain gene rearrangements could be made, 34% had both genes rearranged, 16% had only gamma-chain gene rearrangements, and the remaining 50% had both genes in the germ-line configuration. beta-Chain rearrangements have not been found in the absence of gamma-chain rearrangements, thus supporting a proposed hierarchy of TCR gene rearrangements. A provocative finding was that only a small percentage (11%) of the patients with cALLA- B precursor cell ALLs had rearranged TCR genes, while 50% of the cALLA+ leukemia patients had at least gamma-chain rearrangement, raising a question as to whether indeed cALLA- cells are precursors to cALLA+ cells. Interestingly, 18% (2/11) of the cytoplasmic immunoglobulin (cIg)-positive cALLA+ (pre-B) ALLs involved TCR gene rearrangements, compared to 60% (21/35) of the cIg-negative cases, suggesting the possibility that the majority of functional B cells are derived from the cALLA+ pool that contains immunoglobulin but not TCR gene rearrangements.

Adolescent↗
PubMed1986

Rearrangement and expression of T-cell antigen receptor genes in human T-lymphocyte tumor lines and normal human T-cell clones: evidence for allelic exclusion of Ti beta gene expression and preferential use of a J beta 2 gene segment.

The gene encoding the beta chain of the human T-cell receptor for antigen is composed of variable (V), diversity (D), joining (J), and constant (C) gene segments which undergo specific rearrangements during T-lymphocyte ontogeny. Southern blot analyses of seven human T-cell tumor lines and normal human T-lymphocyte clones revealed that most of these T-cell lines rearrange their Ti beta genes differently. The T-cell tumor line HPB-MLT rearranges and transcribes both of its Ti beta genes. Cloning and sequencing of the Ti beta cDNAs corresponding to these rearrangements revealed that one of the rearranged Ti beta genes is defective, while the other is functional and corresponds to the Ti beta protein expressed on the surface of these cells. Thus, this cell line displays a pattern of allelic exclusion of Ti beta gene expression. A comparison of four C beta 2-containing Ti beta cDNAs from three different cell lines revealed that three of the four utilize the same J beta 2.5 gene segment joined to different D beta and V beta genes, suggesting that there may be preferential use of this J gene during J beta 2 rearrangements. Hybridization analyses with probes for the alpha and beta genes of the T-cell receptor and the T-cell-specific T gamma gene revealed that HPB-MLT cells appear to express approximately equivalent amounts of RNA corresponding to each of the rearranged Ti alpha and Ti beta genes. However, they express a much lower level of T gamma RNA.

Alleles↗
PubMed1982

Primary nodular lymphoma of the lung. Immunoperoxidase and ultrastructural studies.

In two patients, primary nodular lymphomas of the lung which presented incidentally were diagnosed following routine chest radiography, exploratory thoracotomy, and the application of histologic criteria. The diagnoses were confirmed using the peroxidase-antiperoxidase (PAP) technique and transmission electron microscopy. Whereas most investigators had demonstrated intracytoplasmic immunoglobulins in only the large cells of nodular lymphomas using the standard PAP method, we were able to prove the presence of monoclonal immunoglobulin within the cytoplasm of both the large cells and small cells using a modification of the PAP technique as described by DeLellis. This modification uses very dilute antisera and a prolonged incubation time and is more highly sensitive and specific. Monoclonal immunoglobulin was also shown to be within the cytoplasm of mature plasma cells observed within the interfollicular areas. This monoclonal immunoglobulin was the same as that seen within the cytoplasm of the small and large cells of each respective lymphoma. Electron microscopy permitted the identification of three cell types within each patient's tumor: small cells, large cells, and dendritic reticulum cells((DRCs). The finding of the DRCs, presently considered a residual marker of the germinal center, is supporting evidence that both lymphomas studied were nodular lymphomas of B cell derivation.

Female↗
PubMed1979

Chromosomal assignment of the mouse kappa light chain genes.

Mouse-hamster somatic cell hybrids containing a variable number of mouse chromosomes have been used in experiments to determine which mouse chromosome carries the immunoglobulin kappa light chain genes. It has been shown by nucleic acid hybridization that the kappa constant gene and the genes for at least one variable region subgroup are on mouse chromosome 6. This somatic cell genetic mapping procedure appears to be general and can be applied to any expressed or silent gene for which an appropriate nucleic acid probe exists.

Animals↗