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Biomedical subjects

L Goodman

Publications and source records attributed to L Goodman.

At least 37 records · Page 2Linked to original sources
PubMed1998

Solution structures of stromelysin complexed to thiadiazole inhibitors.

Unregulated or overexpressed matrix metalloproteinases (MMPs), including stromelysin, collagenase, and gelatinase. have been implicated in several pathological conditions including arthritis and cancer. Small-molecule MMP inhibitors may have therapeutic value in the treatment of these diseases. In this regard, the solution structures of two stromelysin/ inhibitor complexes have been investigated using 1H, 13C, and 15N NMR spectroscopy. Both-inhibitors are members of a novel class of matrix metalloproteinase inhibitor that contain a thiadiazole group and that interact with stromelysin in a manner distinct from other classes of inhibitors. The inhibitors coordinate the catalytic zinc atom through their exocyclic sulfur atom, with the remainder of the ligand extending into the S1-S3 side of the active site. The binding of inhibitor containing a protonated or fluorinated aromatic ring was investigated using 1H and 19F NMR spectroscopy. The fluorinated ring was found to have a reduced ring-flip rate compared to the protonated version. A strong, coplanar interaction between the fluorinated ring of the inhibitor and the aromatic ring of Tyr155 is proposed to account for the reduced ring-flip rate and for the increase in binding affinity observed for the fluorinated inhibitor compared to the protonated inhibitor. Binding interactions observed for the thiadiazole class of ligands have implications for the design of matrix metalloproteinase inhibitors.

Binding Sites↗
PubMed1998

Editor's note

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Journal Article↗
PubMed1998

Random shotgun fire.

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Human Genome Project↗
PubMed1998

Outcome of ulnar neurolysis during post-traumatic reconstruction of the elbow.

We performed ulnar nerve neurolysis and transposition during reconstructive operations on 20 consecutive patients (21 elbows) with neuropathy after the failure of primary treatment of elbow fractures. There were 11 men and nine women with a mean age of 48.3 years. Preoperatively, four elbows were in McGowan stage I, seven in stage II and ten in stage III and the mean Gabel and Amadio ulnar nerve score was 3.2. At a mean follow-up of 32.1 months (24 to 67) we performed comprehensive neurological, functional, electrophysiological and outcome assessments. Patient satisfaction was high with good pain relief and restoration of hand strength and dexterity. The mean Gabel and Amadio score had improved to 6.5, an improvement of 3.3. There were one excellent, 16 good, 2 fair and 2 poor results; both of the last were due to failure of the underlying elbow reconstruction. Even for advanced stage-II and stage-III lesions we achieved good function, return of intrinsic power, and a high rate of patient satisfaction.

Adult↗
PubMed1997

Haloperidol, lorazepam, or both for psychotic agitation? A multicenter, prospective, double-blind, emergency department study.

Rapid tranquilization is a routinely practiced method of calming agitated psychotic patients by use of neuroleptics, benzodiazepines, or both in combination. Although several studies have examined the efficacy of the three approaches, none have compared these treatments in a prospective, randomized, double-blind, multicenter trial. Ninety-eight psychotic, agitated, and aggressive patients (73 men and 25 women) were prospectively enrolled during an 18-month period in emergency departments in five university or general hospitals. Patients were randomly assigned to receive intramuscular injections of lorazepam (2 mg), haloperidol (5 mg), or both in combination. Patients in each treatment group received 1 to 6 injections of the same study drug within 12 hours, based on clinical need. They were evaluated hourly after the first injection until at least 12 hours after the last. Efficacy was assessed on the Agitated Behavior Scale (ABS), a modified Brief Psychiatric Rating Scale (MBPRS), Clinical Global impressions (CGI) scale, and an Alertness Scale. Effective symptom reduction was achieved in each treatment group with significant (P < .01) mean decreases from baseline at every hourly ABS evaluation. Significant (P < .05) mean differences on the ABS (hour 1) and MBPRS (hours 2 and 3) suggest that tranquilization was most rapid in patients receiving the combination treatment. Study event incidence (side effects) did not differ significantly between treatment groups, although patients receiving haloperidol alone tended to have more extrapyramidal system symptoms. The superior results produced by the combination treatment support the use of lorazepam plus haloperidol as the treatment of choice for acute psychotic agitation.

Adolescent↗
PubMed1996

Characterization of a multicomponent receptor for GDNF.

Glial-cell-line-derived neurotrophic factor (GDNF) is a potent survival factor for central and peripheral neurons, and is essential for the development of kidneys and the enteric nervous system. Despite the potential clinical and physiological importance of GDNF, its mechanism of action is unknown. Here we show that physiological responses to GDNF require the presence of a novel glycosyl-phosphatidylinositol (GPI)-linked protein (designated GDNFR-alpha) that is expressed on GDNF-responsive cells and binds GDNF with a high affinity. We further demonstrate that GDNF promotes the formation of a physical complex between GDNFR-alpha and the orphan tyrosin kinase receptor Ret, thereby inducing its tyrosine phosphorylation. These findings support the hypothesis that GDNF uses a multi-subunit receptor system in which GDNFR-alpha and Ret function as the ligand-binding and signalling components, respectively.

Amino Acid Sequence↗
PubMed1995

Immortalized rat whisker dermal papilla cells cooperate with mouse immature hair follicle buds to activate type IV procollagenases in collagen matrix coculture: correlation with ability to promote hair follicle development in nude mouse grafts.

An in vivo nude mouse graft model and an in vitro collagen matrix culture system were used to study interactions of immature hair follicle buds from newborn mice with clonally derived AdE1A-12S-immortalized rat whisker dermal papilla cell lines. Of the 19 available dermal papilla cell lines, four consistently supported good hair follicle development and hair growth in grafts. Seven cell lines were clearly negative in this assay, and the remaining eight cell lines yielded poor to moderate hair growth. As a correlate to in vivo extracellular matrix remodeling accompanying hair follicle development, type IV collagenase activity in the medium from cocultures of dermal papilla cells and hair follicle buds was analyzed by gelatin zymography. Hair follicle buds cultured alone secrete primarily the 92-kDa type IV procollagenase. Cocultivation of hair follicle buds with eight of the dermal papilla cell lines resulted in activation of this proenzyme and activation of the 72-kDa and 92-kDa type IV procollagenases produced by the dermal papilla cells. Seven of these eight dermal papilla cell lines support hair growth in the graft system. In the absence of dermal papilla cells, several growth factors induced activation of the 92-kDa procollagenase secreted by hair follicle buds cultured in serum-free medium: epidermal growth factor, transforming growth factor alpha, acidic fibroblast growth factor, and keratinocyte growth factor. The current working hypothesis is that a) hair follicle epithelial cells interact with dermal papilla cells in coculture by mutual induction of growth factors and cytokines that stimulate the release and activation of matrix remodeling proteases; and b) the ability of dermal papilla cells to interact with hair follicle epithelial cells in this way may be crucial for controlled dermal matrix remodelling during HF development.

Animals↗
PubMed1994

Basal and induced amounts of interleukin-6 mRNA decline progressively with age in human fibroblasts.

Interleukin-6 (IL-6) is a multi-functional cytokine that plays a role in the body's response to injury and infection. IL-6 expression is induced in young human diploid fibroblasts (HDF) in response to a number of agents including fetal bovine serum, 12-O-tetradecanoylphorbol-13-acetate, double-stranded RNA, and forskolin. In contrast, we find that senescent HDF are markedly deficient in their ability to express IL-6 in response to serum, double-stranded RNA, and 12-O-tetradecanoyl-phorbol-13-acetate, whereas forskolin is still an effective inducer for senescent cells. Thus, specific pathways for stimulating IL-6 expression appear to be blocked in senescent HDF. The basal amount of IL-6 mRNA in unstimulated senescent HDF is also much lower than in unstimulated young quiescent HDF. Likewise, the amount of IL-6 protein produced by senescent HDF is decreased at least 10-fold. Both the basal and induced levels of IL-6 declined progressively with aging of the HDF in culture, e.g. IL-6 cannot be induced above the young basal level by approximately 65% of life-span completed. If a similar decrease in IL-6 expression takes place in HDF in vivo, it could contribute to the decline in wound healing and the increase in the number and severity of infections experienced by aged individuals.

Blood↗
PubMed1993

Regulation of hair follicle development: an in vitro model for hair follicle invasion of dermis and associated connective tissue remodeling.

During embryonic development presumptive hair follicle cells of epithelial and mesenchymal origin are determined in defined body locations. This is followed by rapid proliferation of epithelial cells and associated penetration into the dermis in response to as yet undetermined signals. A collagen matrix culture system, which maintains the three-dimensional relationships of hair follicle cells to each other, was developed to study the regulation of the enlargement of immature hair follicles and the accompanying remodeling of the dermis. In studies with a heterogeneous dermis-derived preparation of murine hair follicles, ranging in size from the earliest down-growing budding cell mass to hair-forming follicles, we had previously shown that cell proliferation was stimulated by cholera toxin and epidermal growth factor, but only the epidermal growth factor-stimulated proliferation was accompanied by digestion of the collagen matrix due to release of collagenolytic enzymes. Further studies revealed that transforming growth factor-alpha also stimulated hair follicle cell proliferation and collagenase release. However, although transforming growth factor-beta inhibited the transforming growth factor-alpha-stimulated proliferation, it enhanced the release and activation of collagenases and other gelatin-degrading enzymes detectable by gelatin zymography. Stimulation of collagenolytic activity depended on the three-dimensional hair follicle structure and did not occur in monolayer cultures of hair follicle cells. Comparison of hair follicle buds with more developed dermis-derived hair follicles, plated at the same cell density (based on DNA content), suggested that a greater fraction of cells in the bud-stage follicle responded to the growth factors by release of collagenases. Possibly only the cells in the advancing portion of growing hair follicles that are closest to the dermal papilla cell cluster produce the collagenases in response to growth factors. To examine the participation of dermal papilla cells in collagenase release and activation, several immortalized rat whisker dermal papilla cell lines were co-cultured with mouse hair follicle buds. Co-culture resulted in a marked enlargement of follicles as well as activation of the 92-kDa type IV collagenase, produced by hair follicle buds, that correlated with ability of the dermal papilla cells to stimulate hair formation in grafts of hair follicle buds on nude mice. Dermal papilla cells cultured alone produced the 72-kDa type IV collagenase, which was also activated during co-culture with hair follicle buds. Thus, two activities, both relevant for hair follicle development, namely, cell proliferation and release and activation of collagenases, have been stimulated in immature hair follicle buds by either growth-factor supplementation or interaction with dermal papilla cells.(ABSTRACT TRUNCATED AT 400 WORDS)

3T3 Cells↗
PubMed1993

In vivo regulation of murine hair growth: insights from grafting defined cell populations onto nude mice.

The nude mouse graft model for testing the hair-forming ability of selected cell populations has considerable potential for providing insights into factors that are important for hair follicle development and proper hair formation. We have developed a minimal component system consisting of immature hair follicle buds from newborn pigmented C57BL/6 mice and adenovirus E1A-immortalized rat vibrissa dermal papilla cells. Hair follicle buds contribute to formation of hairless skin when grafted alone or with Swiss 3T3 cells, but produce densely haired skin when grafted with a fresh dermal cell preparation. The fresh dermal cell preparation represents the single cell fraction after hair follicles have been removed from a collagenase digest of newborn mouse dermis. It provides dermal papilla cells, fibroblasts, and possibly other important growth factor-producing cell types. Rat vibrissa dermal papilla cells supported dense hair growth at early passage in culture but progressively lost this potential during repeated passage in culture. Of 19 E1A-immortalized, clonally derived rat vibrissa dermal papilla cell lines, the four most positive clones supported hair growth to the extent of approximately 200 to 300 hairs per 1-2 cm2 graft area. The remaining clones were moderately positive (five clones), weakly positive (three clones), or negative (seven clones). Swiss 3T3 cells prevented contraction of the graft area but did not appear to affect the number of hairs in the graft site produced by dermal papilla cells plus hair follicle buds alone. The relatively low hair density (estimated 1-5% of normal) resulting from grafts of hair follicle buds with the most positive of the immortalized dermal papilla cell clones compared to fresh dermal cells suggests that optimal reconstitution of hair growth requires some function of dermal papilla cells partially lost during the immortalization process and possibly the contribution of other cell types present in the fresh dermal cell preparation, which is not supplied by the Swiss 3T3 cells. The current graft system, comprising hair follicle buds and immortalized dermal papilla cell clones, provides an assay for positive or negative influences on hair growth exerted by added selected cell types, growth factors, or other substances. Characterization of the phenotype of the dermal papilla cell lines, which differ in their ability to support hair growth when grafted with hair follicle buds, may provide insight into specific dermal papilla cell properties important for their function in this system.

Animals↗
PubMed1992

Co-administration of progabide inhibits haloperidol-induced oral dyskinesias in rats.

Vacuous chewing movements in rats may be an animal analogue of the human motor disorder, tardive dyskinesia. The movements are phenomenologically and pharmacologically similar to tardive dyskinesia. The pathophysiology of these involuntary oral movements, and perhaps of tardive dyskinesia, are likely to include both dopamine receptor changes, and alterations in GABA (gamma-aminobutyric acid) system function. In an attempt to test the involvement of GABA system dysfunction in these movements, we treated rats chronically with water alone, haloperidol alone, the GABA agonist progabide alone, and haloperidol plus progabide. Sprague-Dawley rats received haloperidol (1.5 mg/kg per day) in their drinking water and progabide (100 mg/kg per day) in their food for 12 months. After 12 months of treatment, haloperidol had induced vacuous chewing movements when administered alone, but the prevalence of the movements was decreased by 40% with the coadministration of progabide. Moreover, the haloperidol-progabide-treated animals did not merely demonstrate movement suppression but actual inhibition of movement onset, as determined by an additional progabide-withdrawal experiment. These data would suggest that progabide and perhaps other GABAmimetic compounds can prevent the development of tardive dyskinesia in man.

Administration, Oral↗
PubMed1991

Homelessness as psychological trauma. Broadening perspectives.

Most mental health literature on homelessness has focused on characteristics that may be risk factors for homelessness. The authors of this article argue that homelessness itself is a risk factor for emotional disorder and use the construct of psychological trauma--focusing on social disaffiliation and learned helplessness--to understand the potential effects of homelessness. Psychological trauma is likely among homeless individuals and families for three reasons. (a) The sudden or gradual loss of one's home can be a stressor of sufficient severity to produce symptoms of psychological trauma. (b) The conditions of shelter life may produce trauma symptoms. (c) Many homeless people--particularly women--become homeless after experiencing physical and sexual abuse and consequent psychological trauma. Research suggests that negative psychological responses to traumatic events can be prevented or mitigated by a supportive and empowering posttrauma environment. The implications of trauma theory for improving the psychosocial conditions of homeless people are discussed.

Adaptation, Psychological↗