Biomedical subjects

J Kleinerman

Publications and source records attributed to J Kleinerman.

At least 91 records · Page 5Linked to original sources

PubMed1976

Stochastic model of metastases formation.

A mathematical model is developed to describe the dynamics of the hematogenous metastatic process to the lung from a solid tumor growing in a peripheral body site. The accumulation of tumor cell clumps of various sizes in the pulmonary circulation and the formation of metastatic foci are described by a non-homogeneous, two-dimensional Markov process. An analytical solution is found for the special case of metastases produced by the intravenous injection of tumor cell clumps. The system is decoupled experimentally to determine the time-varying entrance rate of tumor cell clumps into the circulation from a growing fibrosarcoma and the number of metastatic foci produced by the intravenous injection of tumor clumps. Model validation is based on comparisons of model simulations with data for the development of metastatic foci and the probability of cure following tumor excision. The model is used to simulate hypothetical therapy to prevent tumor metastases.

Animals↗

PubMed1975

Serum trypsin inhibitory capacity and Pi phenotypes. I. Methods and control values.

Serum trypsin inhibitory capacity determinations are of considerable value in detecting genetically determined types of obstructive pulmonary disease and hepatic disease. These determinations must frequently be followed by determination of protease inhibitor (Pi) phenotype in order to confirm the diagnosis. Piphenotyping has been a specialized and time-consuming procedure, and suggested improvements in the methodology and technics may make it more generally applicable as a clinical laboratory procedure. The prevalence of phenotypes other than MM in a group of 700 control sera from blood donors is reported as a baseline to evaluate typically American populations of mixed ethnic and racial characteristics. There are suggestive differences in prevalences of S and Z genes relating to ethnic stock and racial groups. It is important when comparing the prevalences of S and Z genes in diseasedpopulations to use control groups of similar ethnic and racial compositions. Pi phenotyping is a necessary laboratory procedure in the diagnosis of certain forms of genetically determined chronic obstructive pulmonary disease and hepatic disease. The distributions of all serum protease inhibitory capacity values and those for S and Z Pi phenotypes are shown.

Adolescent↗

PubMed1975

Serum trypsin inhibitory capacity and pi phenotypes. II. Prevalence of alpha1-antitrypsin deficiency in an allergy population.

A series of 138 patients seen consecutively in an adult allergy clinic were studied to determine serum alpha1-antitrypsin (alpha1-AT) levels and protease inhibitor (Pi) phenotypes. These were compared with a control group of 700 healthy young adult blood donors. Both total serum trypsin inhibitory capacity (STIC) and alpha1-AT levels as determined by immunoelectrophoresis (IEP) were measured. Phenotypes were determined by antigen-antibody-crossed IEP. Alpha1-AT levels in the allergy group were not significantly different from control values. STIC in the allergy group was 1.34 +/- 0.28 mg. trypsin inhibited per ml. serum and in the controls, 1.32 +/- 0.28 mg. IEP values were 205 +/- vs. 200 +/- 36 mg. per dl. Similarly, no increase in Pi phenotypes known to be related to any disease state was observed. Since Pi phenotypes other than the most common MM are rare in Negro populations, phenotype data were corrected to include only Caucasian subjects. In the allergy group adjusted for racial composition we found 2.86% MZ, 5.72% MS; no SZ, SS or ZZ was detected. A comparable control group contained 3.68% MZ, 6.23% MS, 0.71% SZ-SS, but no ZZ Pi phenotype.

Adolescent↗

PubMed1975

Elastic behavior of postmortem human lungs: effects of aging and mild emphysema.

The elastic behavior of postmortem human lungs has been studied in an effort to differentiate the effects of normal aging from those of mild emphysema. Static pressure-volume (P-V) curves were measured in 50 lungs obtained from men 15-85 yr of age, including 12 lungs with mild-to-moderate emphysema. The emphysema was quantitatively assessed by gross and microscopic methods. The P-V relationship in all lungs is accurately described by the empirically fitted equation, P = alpha1ea2v. This expression is useful because the two parameters separate the effects of elastic behavior (alpha1) from size (alpha2) on the P-V curve. There is a close negative correlation (R = -0.94) Between age and alpha1 in normal lungs but no significant age dependence of alpha2. Further decreases in alpha1 are found in most emphysematous lungs. Alpha1 is more than 2 SEE below the age-predicted mean in five of nine lungs with minimal emphysema (1-10% by point count) and more than 5 SEE below the mean in the three more severely affected lungs. There is a close correlation (R = +0.90) between alpha1 and the alveolar surface-to-volume ratio in both normal and emphysematous lungs.

Adolescent↗

PubMed1975