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J Lieberman

Publications and source records attributed to J Lieberman.

At least 163 records · Page 9Linked to original sources

A phosphorylated, disulfide-linked membrane protein in murine cytotoxic T lymphocytes.

The previously determined sequence of the murine T-cell gamma gene and its transcription in cloned T lymphocytes suggests that the polypeptide encoded by this gene is generally present in cytotoxic T cells as a 33-kDa monomer in a disulfide-bonded dimer. The gamma chain is also expected to be phosphorylated because a sequence in its cytoplasmic domain is homologous to an active site for serine phosphorylation in the regulatory subunit of cAMP-dependent protein kinase. We describe here a cytotoxic-T-cell-associated phosphorylated protein, many of whose properties suggest that it may be the product of the T-cell gamma gene. Its phosphorylation is greatly enhanced by interleukin 2 stimulation.

Amino Acids↗

The utility of computed tomography in colonic diverticulitis.

Forty-one patients admitted to our hospital during an 18-month period with the clinical diagnosis of colonic diverticulitis were analyzed to evaluate the utility of computed tomography (CT). Abdominal pain and leukocytosis were the most common presenting manifestations, 75 and 66%, respectively. Just over one-half of the patients also demonstrated hematuria. Twenty patients required surgical intervention, most commonly for failure to improve despite medical management. Preoperative studies included 10 sigmoidoscopies, 30 plain abdominal roentgenograms, 20 barium enemas (BE), and 24 CT scans. Two CT scans were also obtained after operation for successful percutaneous drainage of intra-abdominal abscesses. Abdominal roentgenograms were most commonly obtained but least helpful, with only one third demonstrating any abnormality whatsoever. Sigmoidoscopy was least commonly performed but almost universally abnormal. Specificity was low, however, in that spasm with inability to advance the endoscope was the most common finding. Of the 20 barium enemas obtained, 60% had findings consistent with diverticulitis, most commonly localized perforation or fixed narrow segment. Sixty-three per cent of CT scans were abnormal. The most frequent findings were localized thickening of the colonic wall and increased density in the pericolic fat. Diverticular abscess, which may be inferred by other studies, was definitely diagnosed in one third of the patients with abnormal CT scans. CT also provided the ability to identify extracolonic intra-abdominal pathology. The study demonstrates that both barium enema and CT are effective in diagnosing diverticulitis, although CT can be performed without risk. CT played no therapeutic role before operation, although two patients benefited after operation by CT-guided drainage of intra-abdominal abscesses. The decision for surgery was most frequently dependent on clinical examination and never solely on the basis of either the barium enema or CT in this study. The major benefit of CT appears to be its ability to identify both gross and subtle changes indicative of diverticular disease and extracolonic pathology in a relatively noninvasive manner.

Adult↗

Alpha 1-antitrypsin Pi-types in 965 COPD patients.

To study further the role of intermediate alpha 1-antitrypsin (AAT) deficiency in chronic obstructive pulmonary disease (COPD), AAT Pi-types and serum-trypsin-inhibitory-capacity (STIC) were measured in 965 patients with COPD. Heterozygosity of the Z variant was the major cause of intermediate AAT deficiency (primarily the MZ phenotype), accounting for 8.0 percent of the patients compared to 2.9 percent of control subjects (p less than .0005). ZZ homozygosity was detected in 1.9 percent of the patients, compared to 0.04 percent of control studies performed by others (none was present in our own control group of 1,380 subjects). The mean age for MS or MZ patients did not differ from that of the COPD patients as a whole, whereas the ZZ homozygotes were younger (55.9 +/- 9.8 vs 65.3 +/- 7.5 years). These results resemble those of a previous study in 66 male veterans with pulmonary emphysema suggesting that the MZ phenotype, or intermediate AAT deficiency in general, probably does predispose to the development of COPD. However, the prevalence of AAT deficiency in COPD patients is small (approximately 10 percent). The number with an MS phenotype was not increased in this group of COPD patients.

Adult↗

An angiotensin-converting enzyme (ACE) inhibitor in human serum. Increased sensitivity of the serum ACE assay for detecting active sarcoidosis.

Measurement of serum angiotensin-converting enzyme (ACE) is extremely useful as an aid in the diagnosis and longitudinal evaluation of patients with sarcoidosis. We have detected a human serum ACE-inhibitor which affects the ACE level obtained by activity measurements. The effect of the inhibitor can be eliminated by a mere eight-fold dilution of the serum sample with physiologic saline. We recommend that serum ACE be performed with 1:8 dilutions of serum to eliminate the effect of the ACE inhibitor. The inhibitor has a MW above 50,000 daltons, and reversibility of inhibition by dilution appears to be ion dependent. Dialysis of an inhibitor-containing serum sample against saline causes the inhibition to become irreversible, allowing the distinction between alinearity of the assay vs an inhibitor effect when a serum has ACE activity greater than 50 units/ml. The source of the serum ACE-inhibitor remains to be determined.

Angiotensin-Converting Enzyme Inhibitors↗

Serum angiotensin-converting-enzyme in rabbits with and without pulmonary granulomatosis. Granulomatosis induced with complete-Freund's-adjuvant or BCG.

An animal model with pulmonary, non-caseating, granulomatosis was successfully reproduced in rabbits utilizing intravenous injections of complete-Freund's-adjuvant (CFA) or BCG. Granuloma formation from CFA injections was limited to the lungs, but BCG injections caused systemic granulomatosis (lung, liver and spleen) irrespective of whether the BCG was dissolved in saline or in incomplete-Freund's-adjuvant (IFA). Serum angiotensin-converting-enzyme (ACE) levels began to rise approximately 15 days following the intravenous injection of CFA, but similar rises following the injection of IFA without granuloma formation suggest that the ACE rise was not necessarily reflective of granuloma formation in rabbits. BCG in saline caused no rise in serum ACE, but when suspended in IFA the ACE rise was comparable to that resulting from IFA alone. However, the ACE level of broncho-alveolar-lavage cells obtained from rabbits 21 days post-injection of CFA was 7-fold higher than that of lavaged cells obtained 42 days post injection, correlating with an acute alveolitis occurring early during granuloma formation. These studies confirm the usefulness of intravenous injections of CFA or BCG for inducing a granulomatous state, but show that the assay of serum ACE is not useful for reflecting the granulomatous state in rabbits. In addition, serum ACE levels are 2-5 X higher in rabbits than in humans and tend to fluctuate spontaneously following delivery of the animals to the laboratory.

Animals↗

AIDS and the caregiver.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗

Tardive dyskinesia: prevalence, incidence, and risk factors.

Tardive dyskinesia remains a major concern in psychiatry. Epidemiologic data suggest that the prevalence of the disorder has increased over the past two decades. The average prevalence of TD across various populations is 15%-20%. Abnormal involuntary movements appear to be at least three times more prevalent in neuroleptic-treated patients than in patients not exposed to such drugs. The incidence of TD in a young adult (mean age 27) population is 14% after 4 years of cumulative neuroleptic exposure. The majority of these cases are mild and the condition does not appear to progress in most individuals despite continued neuroleptic exposure. Age remains the single most important risk factor for the development of TD. Recent investigations suggest that patients with affective illness may also be more vulnerable.

Adult↗

Cognitive impairment in tardive dyskinesia.

Psychiatric patients in a prospective study on tardive dyskinesia (TD) development were psychometrically evaluated before TD onset to see whether cognitive impairment predisposes an individual to greater risk for TD. It was found that patients with TD showed more preexisting cognitive impairment than did the non-TD controls.

Adult↗

alpha 1-Antitrypsin deficiency in severe psoriasis.

alpha 1-Antitrypsin phenotypes and trypsin-inhibitory capacities were measured in fifty-one patients with psoriasis. An increased number of variant phenotypes (MS, MZ, and SS) were found only in those patients with severe psoriasis (20% or more skin involvement) and not in those with lesser involvement. The psoriatic patients with variant phenotypes had an earlier disease onset than those psoriatic individuals (both mild and severe) without this association. Protease inhibitors may play a role in modifying disease activity in psoriasis.

Adult↗

Lectin-like factor and co-factor in serum from cystic fibrosis heterozygotes.

Previous attempts to use an assay for a serum lectin-like factor as a carrier test for the cystic fibrosis gene have not been successful because food intake and effects of serum storage have interfered. A revised method for detecting the lectin-like factor employs the serum IgM fraction, rather than whole serum, separated on an S-300 Sephacryl gel filtration column. Elevated lectin titers were found in 95 percent of 43 obligate heterozygotes, 89 percent of patients with cystic fibrosis, 64 percent of siblings of patients with cystic fibrosis, and 5 percent of 60 control subjects. Lectin activity was shown to be associated with the IgM fraction of serum and to result from the binding of a low-molecular-weight co-factor to IgM. Unbound co-factor was also detected in a serum fraction from 81 percent of the heterozygotes and 88 percent of the cystic fibrosis homozygotes, and in a urine fraction from nine patients with cystic fibrosis who had positive serum lectin activity, but not in any urine sample from heterozygous subjects. The presence of co-factor in the urine of cystic fibrosis homozygotes suggests higher serum levels of this agent that spill over into the urine. Intravenous antibiotic therapy removes the lectin and co-factor from blood and urine for variable periods of time, suggesting a beneficial effect of antibiotics in cystic fibrosis apart from their antibacterial action. Detection of the lectin and co-factor are useful in screening for cystic fibrosis carriers, although the somewhat subjective biologic assay requires much experience to achieve reliability.

Adolescent↗

Evidence for a biological hypothesis of obsessive-compulsive disorder.

There is scant but provocative evidence to support the concept of a biological etiology in obsessive-compulsive disorder (OCD). This evidence includes the phenomenologic similarities and associations with other major psychiatric disorders for which there is evidence of biologic etiologies; the genetic studies that show an increased familial occurrence of psychiatric illness including OCD and concordance for this disorder in monozygotic twins; biologic evidence and the historical association of OCD and CNS damage; the treatment response of OCD to antidepressant medication and possibly those medications that selectively modify serotonin neuronal activity and to selective anterior limbic leukotomy. This evidence and the evidence linking OCD to depressive illness are specifically reviewed and discussed.

Adolescent↗

Magnetic resonance imaging of the abnormal female pelvis.

Twenty-three women with 27 instances of pelvic pathology were evaluated by magnetic resonance imaging (MRI). Different pulse sequences were used, which varied the dependence of the images on T1 and T2. Sonography was performed on 22 of the 23 patients. Five patients had CT examinations, including the patient who did not have sonography. MRI was also done in four normal volunteers. The spatial resolution of the MRI scans with short TR and TE intervals approached that of CT. There was overlap of MRI signal characteristics between various pathologic entities and also within the same entity (e.g., cystadenomas and endometriomas).

Appendicitis↗

Serum angiotensin-converting enzyme in severe nonthyroidal illnesses associated with low serum thyroxine concentration.

We evaluated serum angiotensin-converting enzyme levels as an index of thyroid hormone action in severe systemic illness. Angiotensin-converting enzyme was elevated in hyperthyroid patients (37.3 +/- 3.2 U/mL, p less than 0.01) and depressed in hypothyroid patients (17.9 +/- 1.4 U/mL, p less than 0.05). Compared with normal controls (22.6 +/- 1.6 U/mL), patients in an intensive care unit with free thyroxine index greater than 5.0 had normal angiotensin-converting enzyme levels (19.1 +/- 2.5 U/mL), but patients with a free thyroxine index less than 5.0 had angiotensin-converting enzyme levels significantly lower than the normal and hypothyroid groups (10.7 +/- 1.0 U/mL, p less than 0.05). A group of patients in an intensive care unit with alcoholic liver disease (known to elevate angiotensin-converting enzyme) and a low free thyroxine index had depressed angiotensin-converting enzyme levels (16.9 +/- 1.5 U/mL, p less than 0.01). A strong correlation was seen in the combined groups of all patients studied between levels of angiotensin-converting enzyme and a free thyroxine index (r = 0.70, p less than 0.01) and free T3 index (r = 0.72, p less than 0.01).

Critical Care↗