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R Lachman

Publications and source records attributed to R Lachman.

At least 19 recordsLinked to original sources
PubMed2004

A locus for spondylocarpotarsal synostosis syndrome at chromosome 3p14.

Spondylocarpotarsal synostosis syndrome is a rare autosomal recessive disorder characterised by vertebral fusions, frequently manifesting as an unsegmented vertebral bar, as well as fusions of the carpal and tarsal bones. In a study of three consanguineous families and one non-consanguineous family, linkage analysis was used to establish the chromosomal location of the disease gene. Linkage analysis localised the disease gene to chromosome 3p14. A maximum lod score of 6.49 (q = 0) was obtained for the marker at locus D3S3532 on chromosome 3p. Recombination mapping narrowed the linked region to the 5.7 cM genetic interval between the markers at loci D3S3724 and D3S1300. A common region of homozygosity was found between the markers at loci D3S3724 and D3S1300, defining a physical interval of approximately 4 million base pairs likely to contain the disease gene. Identification of the gene responsible for this disorder will provide insight into the genes that play a role in the formation of the vertebral column and joints.

Carpal Bones↗
PubMed1998

Syndrome of coronal craniosynostosis with brachydactyly and carpal/tarsal coalition due to Pro250Arg mutation in FGFR3 gene.

Recently, a unique Pro250Arg point mutation in fibroblast growth factor receptor 3 (FGFR3) was reported in 61 individuals with coronal craniosynostosis from 20 unrelated families [Muenke et al. (1997): Am J Hum Genet 60:555-564]. The discovery of this apparently common mutation has resulted in the definition of a recognizable syndrome, through analysis of subtle clinical findings in families who were previously thought to have a variety of other craniosynostosis syndromes. Previous diagnoses in some of these families have included Jackson-Weiss, Saethre-Chotzen, and Pfeiffer syndromes, as well as Adelaide-type craniosynostosis and brachydactyly-craniosynostosis syndrome [Adès et al. (1994): Am J Med Genet 51:121-130; von Gernet et al. (1996): Am J Med Genet 63:177-184; Reardon et al. (1997): J Med Genet 34:632-636; Bellus et al. (1996): Nat Genet 14:174-176; Hollaway et al. (1995): Hum Mol Genet 4:681-683; Glass et al. (1994): Clin Dysmorphol 3:215-223]. There appears to be a need to further delineate the phenotype associated with this common mutation in FGFR3. We compare the clinical characteristics of previously reported cases of this unique Pro250Arg mutation with those of two additional families and suggest that this syndrome with a unique mutational basis be designated coronal craniosynostosis with brachydactyly and carpal/tarsal coalition due to Pro250Arg mutation in FGFR3 gene, to emphasize the distinctive findings which may be present even in the absence of coronal craniosynostosis.

Abnormalities, Multiple↗
PubMed1998

Lethal syndrome of skeletal dysplasia and progressive central nervous system degeneration.

We describe 3 sibs (2 males and 1 female) with multiple congenital anomalies, poor growth, seizures, and progressive central nervous system (CNS) degeneration leading to death in infancy. Radiographic changes in all 3 were similar, and included moderate shortness of long bones, platyspondyly, and hypoplastic pelvis. Autopsies showed diffuse encephalomyelopathy and enlargement of the lateral and third ventricles. Lysosomal enzyme activities were normal. Collagen type II analysis on 2 of the sibs indicated normal collagen. Chromosomes appeared normal. Even though the radiographic and chondroosseous morphologic findings in these sibs have a certain similarity to Dyggve-Melchior-Clausen syndrome, their clinical course does not fit this condition. These infants appear to represent a new syndrome of bone dysplasia and CNS degeneration inherited as an autosomal recessive trait.

Abnormalities, Multiple↗
PubMed1997

Salaried physicians' intent to retain hospital membership: the effects of position and work attitudes.

This study examined the anticipation of salaried hospital physicians in Israel to retain hospital membership for a long term until their retirement. Examined are attitudinal and position factors, as well as hospital standing personal and situational factors that relate to this anticipation. The data collected from 195 full-time salaried physicians in Israeli hospitals indicated that about one-third of the physicians anticipate to retain hospital membership until retirement. It was found that factors reflecting the physician's standing within the hospital were the main predictors of this anticipation, whereas work-related attitudes had little or no effect on it. The implications of these finding to hospital-physician integration strategies in the United States are discussed.

Attitude of Health Personnel↗
PubMed1996

Reactions of salaried physicians to hospital decline.

OBJECTIVE: To examine the Exit, Loyalty, Voice, and Neglect (ELVN) reactions of full-time salaried physicians to the decline of their employing hospital, and to explore factors possibly associated with the choice of reactions. DATA SOURCE: The study analyzes data collected in a larger survey of work attitudes of 703 hospital physicians, constituting a representative national sample of (every tenth) salaried hospital physicians in Israel. DATA COLLECTION: Data were collected through a self-administered mail questionnaire with return envelopes attached. STUDY DESIGN: A survey design was used. Survey questionnaires included composite measures of the ELVN reaction as well as of the main predictors of reaction choice: job satisfaction, hospital commitment, job investment, alternatives, tenure, and managerial and senior positions. PRINCIPAL FINDINGS: The reactions of salaried physicians to hospital decline include the whole range of ELVN reactions. The choice of each reaction was found associated with a different set of disposition, situation, and position predictors. CONCLUSIONS: The ELVN typology is relevant for examining physicians' reactions to hospital decline, which appear to extend beyond the simple stay/leave dichotomy commonly used. The reactions of Exit, Loyalty, Voice, and Neglect are different in nature, and appear to reflect the different sets of circumstances that salaried physicians may face. Implications of these results for coping with hospital decline, hospital-physician relationships, and integration strategies are discussed.

Attitude of Health Personnel↗
PubMed1995

Severe mid-cervical kyphosis with cord compression in Larsen's syndrome and diastrophic dysplasia: unrelated syndromes with similar radiologic findings and neurosurgical implications.

Mid-cervical kyphosis in diastrophic dysplasia (DD) with cord compression and weakness has been recognized for the last three decades. A strikingly similar situation exists in Larsen's syndrome (LS), an otherwise unrelated problem of weakness with lay joints and dislocations with typical facies. Forty patients with DD were studied of whom seven had cervical spine kyphosis: one patient had spontaneous correction over the ensuing two decades. Seven patients with LS were studied of whom four had cervical spine changes with cord compression. There was one sudden death among the patients with LS and no cases of spontaneous correction. Muscle weakness in DD and LS should lead to evaluation of cervical spine kyphosis with cord compression. Plain films, CT and recently MRI are useful.

Cervical Vertebrae↗
PubMed1994

Desbuquois syndrome: clinical, radiographic, and morphologic characterization.

To further characterize the clinical, radiographic and chondro-osseous morphologic changes in the Desbuquois syndrome, 7 patients from three sibships are described. They all had prenatal onset severe rhizomelic and mesomelic shortness with marked joint laxity and marked micrognathia. Radiographic changes were distinct, consisting of a supernumerary ossification center between the proximal phalanx of the index finger and the second metacarpal, and variable thumb changes. The femoral necks showed enlargement of the lesser trochanter with metaphyseal breaking, producing a characteristic "monkey wrench" (Swedish key) appearance. Growth plate cartilage showed dilated cisterns of rough endoplasmic reticulum in reserve zone chondrocytes. Three of the 7 cases were diagnosed prenatally by second trimester ultrasound and one case by fetoscopy. This syndrome exhibits significant phenotypic variability and must be differentiated from the Catel-Manzke syndrome which exhibits similar radiographic changes in the hands.

Adolescent↗
PubMed1994

Expression, in cartilage, of a 7-amino-acid deletion in type II collagen from two unrelated individuals with Kniest dysplasia.

Kniest dysplasia is a heritable chondrodysplasia that severely affects skeletal growth. Recent evidence suggests that the etiology is based on mutations in COL2A1, the gene for collagen type II. We report the detection and partial characterization of an identical defect in type II collagen in two unrelated patients with Kniest dysplasia. Analysis of cyanogen bromide (CB)-digested cartilage samples from both probands by SDS-PAGE revealed an abnormal band for peptide alpha 1(II)CB12. The peptide was purified and digested with endoproteinase Asp-N. Fragments unique to the Kniest tissues were identified by reverse-phase high-pressure liquid chromatography and by sequence analysis. The results established a deletion of amino acids 102-108 of the alpha 1(II) triple-helical domain, which disrupted the (gly-X-Y)n repeat needed for helix formation. This was confirmed by sequence analysis of DNA amplified from both probands, revealing the molecular basis to be a single nucleotide mutation at a CpG dinucleotide (GCG-->GTG) in the codon for alanine 102. The mutation created a new splice donor site, which would account for the absence of the last seven amino acids from the 3' end of exon 12 in alpha 1(II)CB12. Light and electron micrographs of the probands' cartilage showed the perilacunar foamy matrix ("Swiss cheese") characteristic of Kniest dysplasia and chondrocytes containing dilated rough endoplasmic reticulum, which earlier studies had shown were filled with type II procollagen. These two cases strengthen the concept that Kniest dysplasia is based on mutations of COL2A1 and belongs within the broad spectrum of chondrodysplasias caused by type II collagenopathies.

Adult↗
PubMed1993

Hydrops-ectopic calcification-moth-eaten skeletal dysplasia (Greenberg dysplasia): prenatal diagnosis and further delineation of a rare genetic disorder.

An offspring of consanguineous parents of East-Indian origin was found prenatally to have hydrops fetalis, short limb dwarfism, polydactyly and chondro-osseous changes consistent with Greenberg hydrops-ectopic calcification-moth-eaten skeletal dysplasia (HEM) dysplasia. The radiological changes include platyspondyly with multiple extra ossification centers, extraneous calcification in the ribs, sternum, pelvis, and epiphysis, and moth-eaten long bones. The histopathological changes included chondrocytes with dilated rough endoplasmic reticulum and inclusion bodies with homogeneous material of intermediate electron density. These findings further delineate the spectrum of this rare autosomal recessive skeletal dysplasia.

Abnormalities, Multiple↗
PubMed1993

New form of spondyloepimetaphyseal dysplasia (SEMD) in Jewish family of Iraqi origin.

We report a distinct type of spondyloepimetaphyseal dysplasia seen in 2 sibs and their second cousin, characterized by early onset severe short stature, small chest, and distended abdomen. They had short neck, severe lumbar lordosis, and marked genu varum due to fibular overgrowth and joint laxity. Radiographically, the patients had platyspondyly, initially noted during the first years of life, with central hypoplasia of the vertebral bodies. At a later age, the vertebrae appear squared with mild interpedicular narrowing. The long bone changes, which at early age resemble those seen in achondroplasia, later include general metaphyseal irregularities and significant epiphyseal ossification delay. These patients present a previously undescribed form of spondyloepimetaphyseal dysplasia, most probably transmitted as an autosomal recessive tract.

Child↗
PubMed1993

Hearing loss and temporal bone structure in achondroplasia.

Characteristic temporal bone changes have recently been defined by high resolution CT in nine patients with achondroplasia (Cobb et al., Am J Neuroradiol 9:1195, 1988). These included narrowing of the skull base and "towering" petrous ridges resulting in abnormal orientation of the inner and middle ear structures. In order to determine whether these morphologic changes are the cause of the hearing deficit in achondroplasia, audiometric studies and ENT evaluation were performed in eight of the nine patients. All had a history of frequent otitis media and four had experienced tympanic membrane tube insertion. Three patients had significant sensorineural hearing loss, two had conductive hearing loss and one patient had combined hearing loss. None of the temporal bone morphologic changes were found to be correlated with the degree of either sensorineural or conductive hearing loss. Fusion of the ossicular chain was not present in any of our cases. Appropriate treatment of frequent acute otitis media and early awareness of middle ear effusions and conductive hearing loss in children with achondroplasia may be of great importance in preventing permanent hearing loss.

Achondroplasia↗
PubMed1993

New epiphyseal stippling syndrome with osteoclastic hyperplasia.

We present a lethal skeletal dysplasia characterized radiographically by severe stippling of the lower spine and long bones and periosteal cloaking. In contrast to the normal morphology of the epiphyses and growth plates, the marrow was filled with loose fibrous tissue containing numerous large multinucleated osteoclasts which were associated with Howship's lacunae on the endosteal surface. We suggest the term "Pacman dysplasia" to describe this unusual histologic change that characterizes this new bone dysplasia.

Chondrodysplasia Punctata↗
PubMed1993

Spondylo-meta-epiphyseal dysplasia (SMED), short limb-hand type: a congenital familial skeletal dysplasia with distinctive features and histopathology.

We report on a "new" severe short-limb bone dysplasia which can be labeled descriptively a spondylo-meta-epiphyseal dysplasia. The 3 patients were born to 2 unrelated Sepharadic Jewish families and a Puerto Rican family. Clinical abnormalities include small stature with short limbs including short hands, a short nose with wide nasal bridge and wide nostrils, a long philtrum, ocular hypertelorism, retro/micrognathia, and a narrow chest. Radiological abnormalities include platyspondyly, short tubular bones with very abnormal metaphyses and epiphyses beyond early infancy, short ribs, and a typical evolution of bony changes over time. Chondroosseous morphology and ultrastructure document sparse matrix and degenerating chondrocytes surrounded by dense amorphous material in the 1 patient studied. Consanguinity is present in 1 family. In addition to the described patient, 2 other short-limb sibs, who did not survive infancy, were born into this family. Even in the absence of any photographic or radiologic documentation of these other 2 infants, autosomal recessive mode of inheritance seems probable.

Bone Diseases, Developmental↗
PubMed1993

Physician-hospital conflict among salaried physicians.

Physicians who were full-time salaried employees in nonprofit hospitals experienced conflict between their medical-clinical considerations and the administrative constraints imposed by the hospital. The level of experienced conflict was mostly related to the physicians' commitment to the hospital, the realization in the hospital of their work expectations, and external political influences exerted on the hospital. The implications of the findings for the physicians under a highly controlled work setting are discussed.

Conflict of Interest↗