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Biomedical subjects

J M Friedman

Publications and source records attributed to J M Friedman.

At least 217 records · Page 12Linked to original sources
PubMed1990

Capillary hemangioma of the maxilla. A report of two cases in which angiography and embolization were used.

This article presents two clinical cases of capillary hemangiomas of the maxilla. Such lesions are rare, as demonstrated by the review of the literature included in this article. The presentation, differential diagnosis, histopathology, management, and follow-up for each case are discussed. Our rationale for approaching these types of lesions, as well as our opinion that microembolization should be considered as a first line approach to treatment, is presented.

Adolescent↗
PubMed1990

Molecular mapping of the mouse db mutation.

Diabetes (db) is an autosomal recessive mutation located in the midportion of mouse chromosome 4 that results in profound obesity with hyperphagia, increased metabolic efficiency, and insulin resistance. To clone this gene and generate a molecular map of the region around this mutation, two genetic crosses were established: an intraspecific backcross between C57BL/6J db/db females and C57BL/6J db/db x DBA/2J +/+ F1 (B6D2 db/+ F1) male mice and an interspecific intercross between B6D2 db/+ F1 males and C57BL/6J db/db x Mus spretus F1 (B6spretus db/+ F1) females. The progeny of both crosses were characterized for genotype at the db locus to map a series of restriction fragment length polymorphisms relative to the db locus. Measurements of body weight, body length, and plasma concentrations of glucose and insulin in the animals allowed the assignment of genotype (db/db vs. db/+ or +/+). A total of 132 progeny of the intraspecific cross and 48 db/db progeny of the interspecific cross were typed for individual restriction fragment length polymorphisms to generate a gene order of: centromere-brown (Mt4)-P lambda Mm3(2)-Ifa (Inta)-Cjun-db-D4Rp1-Glut1-Mtv-13-Lck. Several of the genes that are linked to db [Cjun, glucose transporter (Glut1) and Lck] map to human chromosome 1p, suggesting that db may be part of a syntenic group between human 1p and the distal portion of mouse chromosome 4. In addition, phenotyping of the progeny of these crosses revealed a wide range in plasma concentrations of glucose and insulin among the obese progeny, with some animals developing overt diabetes and other remaining euglycemic. Distributions of age-controlled plasma [glucose] and [insulin] among the intraspecific-cross obese progeny were not bimodal, suggesting a role for polygenic differences between the progenitor strains (C57BL/6J and DBA/2J) in the development of overt diabetes.

Animals↗
PubMed1990

Nosological tunnel vision in biological psychiatry. A plea for a functional psychopathology.

Classical nosology has been the major cornerstone of biological psychiatric research; finding biological markers and eventually causes of disease entities has been the major goal. Another approach, one we have designated as "functional," seems possible, attempting to correlate biological variables with psychological dysfunctions, the latter being considered to be the basic units of classification in psychopathology. We have pursued this route for many years, and based on the resulting findings we formulated the following hypothesis. Signs of diminished dopamine, serotonine, and noradrenaline metabolism, as have been found in psychiatric disorders, are not disorder-specific, but rather are related to psychopathological dimensions; i.e., hypoactivity/inertia; increased aggression/anxiety and anhedonia, independent of the nosological framework in which these dysfunctions occur (van Praag et al. 1990). In this paper only the 5-HT data have been discussed. Implications of the functional approach for psychiatry are discussed, including a shift from nosological to functional application of psychotropic drugs. Functional psychopharmacology will be dysfunction-oriented and therefore inevitably geared towards utilizing drug combinations. This prospect is hailed as progress, both practically and scientifically.

5-Hydroxytryptophan↗
PubMed1990

Regulation of N-myc gene expression: use of an adenovirus vector to demonstrate posttranscriptional control.

We present evidence that differences in the levels of N-myc mRNA among different cell types are the result of posttranscriptional control. First, we noted that while steady-state mouse N-myc mRNA could be detected only in fetal mouse brain, it was transcribed at an equivalent rate in adult brain, liver, spleen, and placenta and in fetal brain. Similarly, the human N-myc gene was transcribed at an equivalent rate in HeLa cells, which do not accumulate this RNA in the cytoplasm, and cell lines G401 (a Wilms tumor-derived cell line) and SKNMc (established from a primitive neuroepithelioma), which do express N-myc RNA. As expected, the N-myc promoter functioned at equivalent rates, as demonstrated by the level of a reporter gene, when introduced into these cell types by using a recombinant adenovirus vector. The suggestion that posttranscriptional mechanisms control the level of this RNA was supported by the observation that sequences in the N-myc third exon specifically decreased the level of E1A mRNA when these sequences were placed downstream of the E1A promoter in a recombinant adenovirus. Finally, we further localized these sequences to a 600-bp fragment of the third exon by introducing various subclones of this sequence downstream of the E1A promoter in both viral and plasmid vectors.

Adenovirus Early Proteins↗
PubMed1990

Monoamines and abnormal behaviour. A multi-aminergic perspective.

Classical nosology has been the cornerstone of biological psychiatric research; finding biological markers and eventually causes of disease entities has been the major goal. Another approach, designated as 'functional', is advanced here, attempting to correlate biological variables with psychological dysfunctions, the latter being considered to be the basic units of classification in psychopathology. Signs of diminished DA, 5-HT and NA metabolism, as have been found in psychiatric disorders, are not disorder-specific, but rather are related to psychopathological dimensions (hypoactivity/inertia, increased aggression/anxiety, and anhedonia) independent of the nosological framework in which these dysfunctions occur. Implications of the functional approach for psychiatry include a shift from nosological to functional application of psychotropic drugs. Functional psychopharmacology will be dysfunction-orientated and therefore geared towards utilising drug combinations. This prospect is hailed as progress, both practically and scientifically.

Arousal↗
PubMed1990

Transcriptional regulation of the albumin gene in cultured rat hepatocytes. Role of basement-membrane matrix.

The expression of tissue-specific functions by hepatocytes in primary culture is enhanced in the presence of an extracellular matrix. A basement membrane-like substratum, derived from the Engelbreth-Holm-Swarm mouse sarcoma (EHS) and termed EHS gel, supports synthesis and secretion of albumin for at least three weeks, in contrast to a conventional substratum (plastic or collagen-coated plastic), on which cells rapidly lose this function. The presence of an EHS matrix (as a substratum or added to the medium as a dilute gel) supports transcriptional activity at 30 to 35% and specific mRNA at 70 to 80% of initial values after five days of culture, at a time when transcription in cells plated in conventional culture is undetectable. For examining the cis elements required for transcriptional regulation by EHS matrix, we are utilizing recombinant adenoviruses to introduce DNA into hepatocytes, as an alternative to transfection of DNA fragments. Initial studies are presented, in which hepatocytes are cultured on either collagen-coated plastic or on EHS gel. At various times after plating, the cultures are infected with an adenovirus containing the proximal 5' regulatory region (to -441 base-pair) of the albumin gene. The results indicate no effect of EHS gel on this proximal promoter region, implying that matrix-responsive element(s) lie further upstream, possibly within the previously described enhancer at about -10,000 base-pairs.

Adenoviridae Infections↗
PubMed1990

Potential human teratogenicity of frequently prescribed drugs.

Published data regarding the human teratogenic potential of 157 drug components that are frequently prescribed to outpatients in the United States were evaluated according to a protocol developed for TERIS, an automated clinical teratology resource. This protocol stipulates that a bibliographic search be performed on each agent, a brief narrative summary of the available teratologic information prepared, and a risk rating assigned. The ratings are determined by consensus of five clinical teratologists, who independently assess the magnitude of teratogenic risk associated with each agent under usual therapeutic conditions as "none," "minimal," "small," "moderate," "high," and "undetermined." Forty-nine percent of the components of these frequently prescribed drugs had insufficient published information available to assess the risk of human teratogenicity. Of the agents that could be rated, the teratogenic risk in usual therapeutic doses was considered to be minimal or less in 92.5%. Many of these agents have also been assigned Pregnancy Categories by the United States Food and Drug Administration (FDA) according to a system designed to provide therapeutic guidance. There was no more agreement than that expected by chance between TERIS ratings and the FDA Pregnancy Categories for 83 agents that were classified according to both systems. We believe that the FDA Pregnancy Categories should not be used to provide counseling regarding the risk of teratogenic effects to women who have taken medication during pregnancy. Such counseling should be based on a more comprehensive evaluation of the teratologic literature and clinical situation, but need not involve consideration of the therapeutic benefit of the agent.

Information Systems↗
PubMed1989

Congenital diaphragmatic hernia, coarse facies, and acral hypoplasia: Fryns syndrome.

We describe five patients with Fryns syndrome. Four presented with diaphragmatic hernia and died in the neonatal period. One did not have diaphragmatic involvement and survived but is severely mentally retarded. All patients had "coarse" faces, microretrognathia, macrostomia, and distal digital hypoplasia. In addition to previously reported traits, our patients had clinical manifestations that have not previously been described, including omphalocele, broad clavicles, Hirschsprung "disease," and anal anomalies. The condition was detected antenatally in three of the cases. The patients include two sib pairs, further supporting autosomal recessive inheritance.

Abnormalities, Multiple↗
PubMed1989

Level of expression and chromosome mapping of the mouse cholecystokinin gene: implications for murine models of genetic obesity.

Cholecystokinin (CCK) is a neuropeptide which is present in brain and intestine and which stimulates gall bladder contraction and pancreatic secretion. Additional studies have demonstrated an appetite-suppressing effect of CCK in vivo. These data have aroused speculation that the physiology of this hormone could be relevant in the pathogenesis of the mouse obesity mutations ob on chromosome 6 and db on chromosome 4. In order to determine whether abnormalities of this hormone could be the primary defect in these obesity mutations, we have used three separate approaches to map the mouse Cck gene to distal chromosome 9, where it is part of a syntenic group between mouse chromosome 9 and human chromosome 3. These data therefore exclude cholecystokinin as the etiologic factor in the pathogenesis of any of the known mouse obesity syndromes. In order to exclude the possibility that there are differences in mutant animals in the level of CCK RNA, we have used an S1 nuclease protection assay as well as a novel radioimmunoassay that detects the CCK precursor, to show that there are no gross differences in CCK mRNA or protein precursor levels between ob/ob and wild-type animals.

Alleles↗
PubMed1989

Analysing rearrangement breakpoint distributions by means of binomial confidence intervals.

Non-randomness in the distribution of rearrangement breakpoints can be assessed by means of a binomial probability model. Using the binomial model, we compute confidence intervals for the observed number of breakpoints in chromosome bands and use these confidence intervals to test for non-randomness in a set of 452 constitutional rearrangement breakpoints. This method is useful because it describes the observed data and is not dependent on comparison with a pre-existing hypothesis regarding the distribution.

Biometry↗
PubMed1989

The alpha 2 chain of type 1 collagen does not map to mouse chromosome 16 but maps close to the Met proto-oncogene on mouse chromosome 6.

The gene locus for the alpha 2 chain of type 1 collagen (Cola-2) was previously assigned to chromosome 16. Here we demonstrate, utilising both somatic cell hybrid analysis and genetic linkage analysis, in an interspecific Mus domesticus x Mus spretus cross that Cola-2 fails to cosegregate with mouse chromosome 16, but is linked to the Met proto-oncogene on chromosome 6.

Animals↗
PubMed1989

Expression of the cholecystokinin gene by cultured human primitive neuroepithelioma cell lines.

In this report we identify two cultured human primitive neuroepithelioma cell lines that express cholecystokinin (CCK) RNA and synthesize substantial amounts of pro-CCK, but differ in their ability to process the prohormone. Seven cultured human neural tumor lines, including two primitive neuroepitheliomas and five neuroblastomas, were screened for CCK gene expression using a CCK C-terminal RIA system, a RIA specific for the carboxy-terminal extension of prepro-CCK, and RNAse protection assays specific for CCK mRNA. RNA derived from the two primitive neuroepitheliomas yielded strong hybridization signals with CCK-specific probes. The five other neuronal tumors were negative for CCK mRNA. The two primitive neuroepitheliomas also synthesized substantial quantities of material reactive in the CCK carboxy-terminal extension RIA system. One of the tumors, Sk-N-Mc, postranslationally processed the CCK prohormonal material poorly, yielding only high mol wt CCK precursors and no immunoreactive CCK. The other, SK-PN-Dw, was able to process the prohormone, producing immunoreactive CCK-like material plus a peptide that immunochemically and chromatographically resembled the intact CCK C-terminal extension peptide. These cultured tumor lines should prove useful in furthering our understanding of the regulation of the CCK gene in human neuronal cells and will also provide an in vitro system for investigation of the posttranslational processing of the CCK preprohormone. In addition, the data demonstrate that screening procedures for examining peptide hormone expression by tumors are most comprehensive when specific molecular genetic probes are employed in addition to standard peptide assay methodology. Finally, these data suggest that CCK production may be a feature of some primitive neuroepitheliomas.

Animals↗
PubMed1989

Encephalocraniocutaneous lipomatosis. Report of two cases and a review of the literature.

We describe 2 patients with unilateral facial and cerebral malformations consistent with encephalocraniocutaneous lipomatosis. The characteristic facial appearance seems to develop with age, possibly as a consequence of increased intracranial pressure. However, the clinical data suggest that this condition arises as a result of a disruption of cephalic neural crest and anterior neural tube.

Adolescent↗