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Biomedical subjects

S Snyder

Publications and source records attributed to S Snyder.

At least 73 records · Page 4Linked to original sources
PubMed1990

Change in diagnosis at termination of psychiatric consultation.

Changes in 358 initial diagnoses made by psychiatric consultants in a medical inpatient setting were examined. Initial diagnoses from five groups--major depression, adjustment disorder with depressed mood, dementia, delirium, and the somatoform disorders--were compared with diagnoses made at termination of consultation. Differences in stability of diagnosis between the groups failed to reach significance (pz = .078). However, a trend was found for diagnoses of major depression to be the least stable; 21.7 percent of initial diagnoses were changed by termination. The results emphasize the provisional nature of initial psychiatric diagnoses in the medical setting and suggest the need for repeated assessment of the patient before beginning potentially hazardous treatment, especially for major depression.

Diagnosis, Differential↗
PubMed1990

MR arthrography of the shoulder: comparison with conventional MR imaging.

Twenty-three patients underwent both conventional MR imaging of the shoulder and MR shoulder arthrography for clinically suspected labral or rotator cuff abnormalities. Images obtained before and after contrast administration were studied independently, and without knowledge of clinical findings, by two radiologists for the presence of abnormalities of the glenoid labrum or rotator cuff. Results were correlated with surgical findings in all patients. Nine patients had surgically proved labral tears. MR arthrography detected all nine labral abnormalities, while six of the nine were missed on conventional MR imaging. Fourteen patients had surgically proved rotator cuff tears. MR arthrography detected 11 of the 14 tears and missed three partial tears on the bursal surface. Conventional MR imaging detected nine cuff tears and missed five tears; two of these were complete rotator cuff tears and three were partial tears of the undersurface of the rotator cuff. Our results suggest that MR arthrography enhances the accuracy of MR in the evaluation of the glenoid labrum and rotator cuff tendon.

Adolescent↗
PubMed1990

Comparison of cholesterol-lowering regimens.

Drug therapy should be reserved for patients with marked total cholesterol elevation not amenable to dietary measures. While current guidelines suggest that bile acid sequestrants, such as cholestyramine and colestipol, are first-line drugs for the treatment of hypercholesterolemia, recent studies suggest that lovastatin is a safe, more potent alternative. Gemfibrozil reduces the serum triglyceride level and raises the high-density lipoprotein (HDL) cholesterol level, but has only a moderate effect on the serum cholesterol level. Nicotinic acid lowers serum low-density lipoprotein (LDL) cholesterol and triglyceride levels and raises serum HDL levels, but its use is limited because of troublesome side effects, notably a flushing reaction. Probucol lowers both serum LDL and HDL levels and is a second-line agent for the treatment of hypercholesterolemia.

Anticholesteremic Agents↗
PubMed1990

Evaluation and treatment of mental disorders in patients with AIDS.

Mental symptoms are common in patients with AIDS. Optimal management involves the identification and treatment of underlying mental disorders rather than symptomatic treatment alone. Organic mental disorders are very frequent in AIDS, particularly with seriously ill patients who are medical inpatients. There is a high priori probability that such common symptoms as agitation, irritability, and insomnia will be caused by an organic mental disorder. Psychopharmacology in the patient with AIDS requires considerable caution. Lower doses and careful surveillance for subtle neuropsychiatric side effects are necessary. Routine medical contact with a compassionate physician may be of inestimable value to the patient in coping with the fear and dread that surround the illness.

AIDS Dementia Complex↗
PubMed1989

Cellular forms of the rat and human beta-amyloid precursor protein (BAPP).

Using synthetic peptide antisera generated against beta-amyloid precursor protein (BAPP) sequences we demonstrate that the newly synthesized BAPP appears as a 94 kDa peptide in rat brain RNA cell-free translates or polysome runoffs, while from similar human brain material we see two bands at 94 and 120 kDa. Immunoblots reveal likely post-translational modification of BAPP, and possibly an age-dependent, endogenous proteolysis of the protein in rat brain. On human brain immunoblots an unusual post-translational modification or possibly oligomerization of BAPP is seen, particularly in cortical regions.

Aging↗
PubMed1989

Somatoform disorders in the general hospital inpatient setting.

The somatoform disorders present dilemmas on acute inpatient medical/surgical services because they may closely mimic authentic physical illness and result in misapplied medical treatment. However, there have been few diagnostic studies of this important group in the medical/surgical inpatient setting. Inpatient psychiatric consultations at Mount Sinai Medical Center during 1980-1987 were recorded using a 384-item computerized data base protocol. DSM-III somatoform disorders were identified in 33 of 1801 initial consultations (1.8%) and in 35 of 1363 at time of termination (2.6%); demographic and diagnostic characteristics of somatoforms and others were compared. The question of a psychogenic component to the illness and problem with pain management were the most common stated reasons for consultation. Somatoform patients were more likely than others to be female (p less than 0.05), Hispanic (p less than 0.05), and to have Axis II comorbidity (p less than 0.001). Axis III comorbidity was present in 94%. Thirty-one percent of patients diagnosed as somatoform on final follow-up assessment had not been diagnosable as somatoform on initial assessment. The findings emphasize the necessity of ongoing assessment in improving diagnostic certainty, as well as the prevalence and importance of medical comorbidity among patients with somatoform disorders in this setting.

Hospitals, General↗
PubMed1989

Cloning of a cDNA encoding the rat high molecular weight neurofilament peptide (NF-H): developmental and tissue expression in the rat, and mapping of its human homologue to chromosomes 1 and 22.

Neurofilaments (NFs) are the intermediate filaments specific to nervous tissue. They are probably essential to the tensile strength of the neuron, as well as to transport of molecules and organelles within the axon. Three peptides with apparent molecular masses of approximately 68 (NF-L), 145 (NF-M), and 200 (NF-H) kDa appear to be the major components of NF. The expression of these peptides is specific to nervous tissue and is developmentally regulated. Recently, complete cDNAs encoding NF-L and NF-M, and partial cDNAs encoding NF-H, have been described. To better understand the normal and pathophysiology of NFs we chose to clone the cDNA encoding the rat NF-H peptide. Using monoclonal antibodies that recognized NF-H, we screened a rat brain lambda gt11 library and identified a clone that contained a 2100-nucleotide cDNA insert representing the carboxyl-terminal portion of the NF-H protein. Anti-fusion protein antibodies recognized the NF-H peptide on immunoblots and stained fibrillar structures only in neurons. The cDNA recognized a 4500-nucleotide polyadenylated mRNA that was present only in nervous tissue and a 3500-nucleotide mRNA in adrenal. Brain NF-H mRNA levels were tightly developmentally regulated and paralleled the levels of NF-H peptide on immunoblots. Nuclear runoff studies showed that the 20-fold developmental increase in the NF-H message was due only in part to a 4-fold increase in its transcription rate. Levels of NF-H mRNA varied 20-fold among brain regions, with highest levels in pons/medulla, spinal cord, and cerebellum, and lowest levels in olfactory bulb and hypothalamus. Transcription studies revealed only a 2-fold difference in the transcription rates among these brain regions. Based on these results, we infer that half of the developmental increase and most of the interregional variation in the levels of the NF-H mRNA are mediated through message stabilization. Sequence information revealed that the carboxyl-terminal region of the NF-H peptide contained a unique serine-, proline-, alanine-, glutamic acid-, and lysine-rich repeat. The serine residues are likely sites of phosphorylation in the mature peptide. Genomic blots revealed a single copy of the gene in the rat genome and two copies in the human genome. In situ hybridizations performed on human chromosomes mapped the NF-H gene to chromosomes 1 and 22. Whether one copy is a pseudogene remains to be determined.

Aging↗
PubMed1988

Synovisol as an irrigant for electrosurgery of joints.

The appropriate irrigation fluid for use during arthroscopic procedures should be selected on the basis of fluid-tissue and fluid-instrumentation compatibility. This study describes a new irrigation fluid, Synovisol, that is isomolar, nonhemolytic, nonantigenic, has a low viscosity, and is nonconductive. The rabbit knee was used as a model to demonstrate the immediate and long-term (3 weeks) effects of irrigation with Synovisol compared with water, normal saline, mannitol, sorbitol, glycine, and with nonirrigated controls. Results were assessed by light- and electron-microscopic evaluation of synovium and cartilage dissected from rabbit knees. While the greatest amount of damage was seen in water-treated samples, significant effects were noted with other irrigants compared with Synovisol and controls. Long-term animals showed recovery of tissues in all cases. Systemic effects evaluated by measuring plasma glycerol levels showed a transient increase that peaked at 20 min. No hemolysis was detected and kidney morphology was normal. The physiological, electrocompatible, simplicity of formula, low cost, and long-shelf-life properties of this solution makes it a fluid uniquely suited to arthroscopy.

Animals↗
PubMed1987

Cell and species differences in metabolic activation of chemical carcinogens.

Metabolic activation and DNA binding of aflatoxin B1 (AFB1), N-nitrosodimethylamine (DMN) and benzo[a]pyrene (B[a]P) were compared in human, rat and mouse hepatocytes and human pulmonary alveolar macrophages (PAM). The degree of carcinogen activation by hepatocytes and PAM was measured by cell-mediated mutagenesis assays in which co-cultivated Chinese hamster V79 cells were used to monitor mutagenic metabolites. Hepatocytes from human, mouse and rat metabolized DMN and released the active metabolites to induce either ouabain- or 6-thioguanine-resistant mutation. The mutation frequencies mediated by hepatocytes of the 3 animal species were approximately 3-9 mutants/10(5) survivors at a concentration of 0.2 mM DMN. The variations of radioactivity bound to liver cell DNA were relatively small in cultured mouse, rat, and human hepatocytes exposed to 14C label DMN (0.5 mM) and the binding values were in a range of 6-12 X 10(3) pmoles/mg DNA. However, rat hepatocytes were at least 10-fold more effective than either human or mouse hepatocytes in generating mutagenic metabolites of AFB1 and also had a much higher AFB1 metabolite DNA-binding value. The AFB1 DNA-binding levels were 4.1, 12-27 (range), 120 pmoles/mg DNA respectively in mouse, human, and rat liver cells following AFB1 (3.3 microM) exposure for 20 h. Hepatocytes from the 3 animal species were unable to mediate mutation in the presence of 4 microM B[a]P; PAM activated B[a]P and effectively mediated mutation in the co-cultivated V79 cells. In contrast to results with hepatocytes, PAM failed to generate enough mutagenic metabolites of AFB1 (3.3 microM) and the mediation of mutations was seen only at very high concentration of DMN (80 mM). The genotoxic effects of the 3 carcinogens on hepatocytes from different species in vitro were in agreement with the in vivo animal experiments in that mice are relatively resistant to AFB1 carcinogenesis whereas rats are sensitive; B[a]P is not effective as a complete liver carcinogen in adult rat and mouse whereas DMN induces liver cancer.

Aflatoxin B1↗
PubMed1986

Characterizing somatization, hypochondriasis, and hysteria in the borderline personality disorder.

Somatization, hypochondriasis, and hysteria have often been considered as associated features of the borderline personality disorder. This study was designed to characterize these three syndromes in the borderline patient. Inpatients with DSM-III borderline personality disorder were compared with controls with dysthymic disorder. Scales and items from standardized rating instruments which measured the three syndromes were scored and compared between groups. Although the hysteria-obvious and hypochondriasis scales of the MMPI and the Hamilton Depression Scale item measuring hypochondriasis were elevated in the borderline group, there were no significant differences between groups. Scores of dysthymic patients significantly exceeded those of borderline patients on four of five MMPI codetypes measuring the three syndromes. Findings are discussed in light of previous psychodynamic, empirical, and research literature.

Adolescent↗
PubMed1986

Characterizing paranoia in the DSM-III borderline personality disorder.

The relationship between paranoia and the borderline personality disorder continues to be the subject of debate. This study compares the extent and intensity of paranoia in 29 subjects fulfilling DSM-III criteria for borderline personality disorder. The control group consists of 22 subjects with dysthymic disorder. Paranoia was both more prevalent and severe in borderline patients. Results are discussed in light of previous descriptive and research literature.

Adolescent↗
PubMed1986

Selected behavioral features of patients with borderline personality traits.

Selected behavioral features felt historically and empirically to be significant in the borderline personality disorder were evaluated in 4,800 psychiatric inpatients. Variables measured included number of hospitalizations and type of discharge, suicidal behavior, physical violence, and outcome after discharge. A statistical analysis was performed to determine the relationship between depth and severity of borderline traits and the aforementioned behavioral features. Results indicated that irregular discharges, frequent suicide attempts, first suicide attempt prior to age 40, violence within and outside the hospital, and gradual deterioration in social and occupational functioning were found significantly more often in patients with high levels of borderline personality traits.

Adult↗