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S Cleveland

Publications and source records attributed to S Cleveland.

At least 19 recordsLinked to original sources
PubMed1992

The influence of bacterial collagenase on regeneration of severed rat sciatic nerves.

Regeneration of peripheral nerve fibers is impeded by the formation of scar tissue at the site of injury. The possible beneficial effect of collagenase on nerve regeneration was studied using clinical, neurophysiological (evoked potentials) and histological (nerve fiber counts) methods. The sciatic nerves of rats were transected and the severed ends abutted and sewn together. In one series, the area about the lesion was covered with fibrin adhesive and infused with either isotonic saline (controls) or collagenase (treatment group). In the other series, the severed ends of the nerve were inserted into a silicone tube and separated by a collagen plug, which was infused with either saline or collagenase. Compared to the controls, the treated animals showed a significant improvement of clinical and neurophysiological parameters. After 3 months of observation, the collagen content of the transection site was reduced, and in the silicone series, the total number of myelinated axons 5 mm distal to the site of transection was increased, while the fiber diameter distribution was unchanged.

Animals↗
PubMed1992

Association of Crohn's disease and multiple sclerosis. Is there a common background?

Crohn's disease (CD) and multiple sclerosis (MS) share familial occurrence and similar epidemiological traits. Apart from one report of both diseases occurring among consanguineous relatives, only three cases of CD and MS in the same patient have thus far been described. We describe here a 29-year-old woman in whom MS developed in 1983 and CD in 1989. The MS may have been the result of a strongly HLA-associated genetic predisposition, while the additional development of CD may have been due either to genetic factors or perhaps simply to chance. Viewing this case in the context of epidemiological data, however, we suggest that the development of CD and MS is based on one or more common genetic factors acting in conjunction with other presumably exogenous factors and triggering HLA antigens to lead to one disease or the other.

Adult↗
PubMed1991

[Various genetic models in Crohn disease].

Crohn's disease has a genetic predisposition. In the light of epidemiological data, especially the type of familial clustering, simple modes of inheritance can be excluded. At the first glance, our results implied a polygenic multifactorial basis. Further processing of our data by the "mixed model" of Morton revealed a higher probability for a recessive gene with low penetrance. However, the differences in fit between the various models are relatively slight. Also considering ascertainment problems, a definite decision concerning an appropriate model must be deferred until sure genetic markers have been identified. Nevertheless, only a certain number of manifestations may be ascribed to a genetic predisposition, others have to be catagorized as phenocopies.

Adolescent↗
PubMed1990

Gene and haplotype frequencies of HLA antigens in 269 patients with Crohn's disease.

Evidence of strong genetic markers in Crohn's disease (CD) is still absent. Many investigations have focused on HLA antigens, with conflicting results. To obtain more detailed information on the relation of HLA to the disease, we used the HLA data from 269 CD patients to compute the maximum-likelihood estimates of HLA gene and haplotype frequencies. These results provide further evidence that HLA B44 and Cw5 do indeed play a role in the development of CD. Furthermore, it is conceivable from our results that HLA Cw7 may protect against being affected with this disease.

Chi-Square Distribution↗
PubMed1990

[T-lymphocyte subpopulations in the peripheral blood of patients with Crohn disease].

Immunological disorders seem to be of considerable relevance to the pathogenesis of Crohn's disease (CD). T-cells play a central role in immunoregulation. The T-cell subpopulations of 70 patients with CD were compared to those of age- and sex-matched healthy controls. The suppressor-inducer subpopulations were found to be reduced in CD patients irrespective of wether they were taking steroids or not. In contrast to other subpopulations suppressor-inducer cells remained unchanged during follow-up. The results point to a disturbance in the regulation of suppressor T-cells in patients with Crohn's disease.

Adrenal Cortex Hormones↗
PubMed1990

Crohn's disease in four members of a family, two of whom are dizygotic twins.

Familial occurrence of Crohn's disease (CD) is well known, but the disease is rarely reported to occur in dizygotic twins. We present an additional case of dizygotic twins, both of whom developed CD, from a family in which two other members are affected. The 16-year-old son contracted the disease 2 years before his 50-year-old father, and 13 years before his twin sister. Another sister was affected 6 years after the onset of the disease in the propositus. HLA haplotyping of the three children matched the Mendelian ratio. The multiple occurrence of CD in blood relatives, especially in siblings, emphasizes the importance of genetic factors in the development of this disease. This family history, however, could point to psychic influences promoting the occurrence of CD on the basis of a polygenic disease susceptibility.

Adolescent↗
PubMed1989

On the construction of cross-sectional statistical standards for growth.

Cross-sectional growth studies generally produce standardizing groups which are too small to permit the direct construction of standards. This problem can be circumvented by the introduction of appropriate structural assumptions. The two key papers in the literature which focus on this issue, Healy (1962) and Goldstein (1972), give methodologies which involve somewhat different premises. Healy takes the ages of individuals to be uniformly distributed over a well-defined interval (but their precise levels unknown). Goldstein by comparison supposes age levels to be known exactly. Both authors postulate that the characteristic of interest follows a Gaussian density whose mean and variance are each linear functions of time, a + bt and c + dt, say. In this paper we begin to explore the robustness of the two methods. Our results show that Healy's original moment solution to the estimation of (a, b, c and d) may be quite insensitive to departures from a uniform distribution for ages provided that this distribution remains symmetric about the interval mid-point. Moreover, the distribution of the characteristic of interest may deviate from the Gaussian without too much effect, provided that symmetry about the mean a + bt is retained. However, there is much more doubt about asymmetric departures in both cases especially with regard to the estimation of b and d. Opting for simple 'interpolated' estimates of these two parameters (when possible) rather than Healy's original formula-based versions will strongly aid robustness in general.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1989

Commitment: the consistency of clinicians and the use of legal standards.

The reliability and validity of the application of legal criteria for commitment were investigated as part of a larger study. Evaluations of 411 patients by 96 different clinicians showed good interrater reliability for assessment of dangerousness and committability. A strong relationship between ratings of committability and ratings of dangerousness suggests that clinicians were conforming to the logic of the commitment law. Discrepant cases involved patients who desired voluntary admission or whose commitment was completed elsewhere. Results suggest fair application of commitment standards but that two issues of statutory interpretation confused participating clinicians.

Commitment of Persons with Psychiatric Disorders↗
PubMed1989

Do dangerousness-oriented commitment laws restrict hospitalization of patients who need treatment? A test.

A study at a large urban psychiatric hospital in Pennsylvania evaluated whether the state's dangerousness-oriented commitment criteria restricted hospitalization of patients whom emergency room clinicians considered highly in need of treatment but not dangerous. A total of 390 patients were studied. Eleven patients judged to be highly in need of treatment did not meet any of the commitment criteria, but they were largely compliant with the idea of being treated. An additional 17 patients considered highly in need of treatment met criteria for commitment based on inability to care for self, but most were hospitalized voluntarily. Only one patient who met none of the commitment criteria resisted recommended hospital care, and she was eventually committed involuntarily based on inability to care for self. The data suggest that dangerousness-oriented commitment criteria are flexible enough to provide for treatment of patients in serious need.

Activities of Daily Living↗
PubMed1989

Investigation of genetic markers in patients with Crohn's disease and ulcerative colitis.

Inflammatory bowel diseases (IBD) as Crohn's disease (CD) and ulcerative colitis (UC) are believed to have a genetic basis. Additional factors are supposed to promote the development of IBD. However, apart from a few reports of HLA associations which await confirmation by other groups strong associations to (a) particular genetic marker(s) are still lacking. We here report on previously unobserved associations of CD to MNSS and UC to the immunoglobulin heavy chain allotype Gm 1,-2,10. We suggest that these factors play a role in a wider spectrum of genetic markers for the development of IBD.

Acid Phosphatase↗
PubMed1988

Association of Crohn's disease with HLA phenotype B44, Cw5.

Genetic influence on the development of Crohn's disease (CD) is commonly accepted. However, proof of definite genetic markers is still pending. Most investigations have focused on HLA antigens, and associations with HLA B12 and HLA A2 have been reported, but the design of these retrospective studies is open to criticism. We have undertaken a consecutive study of 96 patients with CD under well-defined conditions in order to test the hypothesis that CD is associated with particular HLA antigens. Our results identify a significant association of CD with the phenotype HLA B44,Cw5. But since a major proportion of the CD patients do not bear this phenotype, other predisposing genetic factors, which have not yet been defined, may exist in addition to environmental factors.

Adolescent↗
PubMed1988

HLA antigens in ankylosing spondylitis associated with Crohn's disease. Increased frequency of the HLA phenotype B27,B44.

In a consecutive case study 231 patients with Crohn's disease were investigated for ankylosing spondylitis (AS) and HLA-A, B, C, DR antigen association. Eighteen patients (7.8%) had definite AS according to the New York criteria; 13 (72%) were HLA-B27 positive. The phenotype B27,B44 was seen in 8 patients (44%) compared to only 3 (1%) of 300 controls (p less than 10(-7), and 1 (0.5%) of 213 patients with Crohn's disease without AS (p less than 10(-7). We conclude that patients with the phenotype B27,B44 are highly at risk (relative risk = 68.8) for the common manifestation of Crohn's disease and AS.

Adult↗
PubMed1987

Crohn's disease in a married couple.

The aetiopathogenesis of Crohn's disease is still unknown. Multiple occurrence of inflammatory bowel disease among blood relatives of patients with either Crohn's disease or ulcerative colitis is seen much more frequently than would be expected by chance alone, whereas reports on the development of these diseases in spouses are very rare. We describe such a case here, and suggest that chance, rather than an infectious agent, is behind such occurrences.

Adult↗
PubMed1986

Monozygotic triplets with Crohn's disease of the colon.

Female monozygotic triplets all developed Crohn's disease within a period of 11 mo. The monozygosity was demonstrated by analysis of 24 genetic markers of different chromosomal localization. Crohn's disease was diagnosed using clinical, radiologic, and endoscopic findings. Histologic evaluation of bowel tissue was consistent with Crohn's disease. All 3 patients had colon involvement; the terminal ileum appeared normal. The patient in whom Crohn's disease was first diagnosed had the severest course. Our observations support the role of a genetic influence in the manifestation of Crohn's disease. Nevertheless, environmental factors or microorganisms, or both, have to be taken into account, perhaps as factors promoting the outbreak of Crohn's disease.

Adult↗
PubMed1984

Chronic inflammatory polyneuropathy. Reduction of nerve conduction velocities in monkeys by systemic passive transfer of immunoglobulin G.

In chronic (relapsing) inflammatory polyneuropathy (CRIP), successful treatment with plasma exchange has led to the concept of pathogenic humoral factors. In 6 patients with CRIP, 5 of whom improved after plasma exchange, the potential pathogenic role of circulating immunoglobulin (Ig) fractions was tested by applying the systemic passive transfer model to marmoset monkeys. After continuous treatment with intramuscular injections for 2-8 weeks, monkeys injected with the crude immunoglobulin fractions or with purified IgG from 5 of the 6 patients showed a significant and partially reversible reduction of the motor nerve conduction velocity (mean 34%, P less than 0.001) when compared with pre-treatment values. In control animals the reduction was 4%. Morphological examination revealed only minor ultrastructural changes of the myelin sheath. Immunocytochemistry revealed that human IgG was able to cross the blood-nerve barrier. It is concluded that the circulating IgG-fraction of patients with CRIP contains a factor that may contribute to the disordered nerve function after crossing the blood-nerve barrier. It may be the removal of this particular factor which is responsible for the rapid recovery of nerve conduction in patients after plasma exchange.

Animals↗
PubMed1982

Dynamic properties of Renshaw cells: equivalence of responses to step changes in recruitment and discharge frequency of motor axons.

In decerebrate cats, the dynamic responses of Renshaw cells to step changes in input were determined separately both for changes in the number of alpha-axons excited and for changes in the frequency at which they were stimulated. Together, these two input variables to the Renshaw cells describe the level of activity in the motor output from the spinal cord. In either case, the dynamic responses of the interneurons depend only on their static activity before and after an input step occurs, but are otherwise indistinguishable. This favors the interpretation that the two input variables are equivalent under dynamic conditions, i.e., Renshaw cells respond to total motor output.

Animals↗