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PubMed1991

Developmental hematopoiesis in normal human fetal blood.

Using an easy and safe procedure for fetal blood sampling in utero, we studied 3,415 fetuses for prenatal diagnosis. Retrospectively, 2,860 normal blood samples, performed from the 18th week of gestation to the end of pregnancy, were selected. Differentials were evaluated in 732 cases. Burst-forming unit erythroid (BFU-E) and erythropoietin (Epo) were measured in 27 and 163 cases, respectively. Total nucleated cell and platelet counts did not change from the 18th to the 30th week of gestation. The lymphocytes represented the main population and the decrease of normoblastic cells made up for the increase in neutrophils. The increase of red blood cells and hemoglobin was substantial during the studied period. At mid trimester threefold more BFU-E were obtained than at birth. Epo levels remained stable throughout the pregnancy and no correlation was found between Epo and gestational age. These normal values of fetal erythropoiesis will improve our knowledge of physiology and provide a better insight into developmental hematopoiesis.

Adult↗
PubMedDate not supplied

Evaluation of computer case simulations for teaching clinical pathology to second-year medical students.

A computer-assisted learning program for teaching clinical pathology to second year medical students has been developed and evaluated. These programs are designed to be used as supplements to formal lectures, laboratory exercises, and small group discussions. Students are given case histories and asked to select differential diagnoses, order and interpret laboratory and diagnostic tests, and make final diagnostic conclusions. In some cases, laboratory monitoring of treatment, e.g., drug therapy, is emphasized. The performance of the student is objectively evaluated during each stage. In addition, the amount spent for each workup is recorded with penalties given for excess or inappropriate test ordering. Separate evaluations are performed to assess the effectiveness of these programs as an alternative teaching format to (1) formal lectures and reading assignments, and (2) faculty-directed small group discussions. It is concluded that the computer-assisted learning method is equivalent to lectures and group discussions and is a format that is well accepted by students.

Computer-Assisted Instruction↗
PubMedDate not supplied

[Populational speciation or chromosomal speciation? About the book of Jean de Grouchy "From the birth of species to the aberrations of life" (author's transl)].

According to Jean de Grouchy, the emergence of a new species is dependent on an "acceptable" chromosomic rearrangement, which passing from the heterozygous state (in the original bearer) to the homozygous state (in some of his enbred offspring) becomes definitively established and creates a population sexually isolated from its acestors. He is thus using the idea of karyotype to develop the typological theory put forward at the beginning of the century which postulates that a single mutant is at the origin of a new species. Although he gives an important place to chromosomic rearrangements in the sexual isolation of a new species, J. Ruffié demonstrates by arguments taken from population genetics and from the immunological polymorphism of wild populations that speciation is almost always the result of the evolution of an entire group, which, because of geographic isolation, drift, and differential selection, diverges from the ancestral branch and finally becomes totally incapable of breeding with it. He proposes a model of speciation which includes the two processes population and cytologic. At a first step, the group is isolated geographically and continues its independent evolution; the second step consists of chromosomic recombinations which render the sexual isolation complete. The modifications of the karyotype make the process of speciation irreversible.

Adaptation, Physiological↗
PubMed1990

New issues in the prediction of antidepressant response.

Over the past three decades, certain clinical factors have been identified as either positive or negative predictors of response to treatment with the tricyclic antidepressants (TCAs), and have been well reviewed in the psychopharmacology literature. The current report is an effort to focus attention on methodologic and clinical issues that have recently been given attention in this area and that may be useful to clinicians and researchers. The specific issues addressed are (a) the implications of the definitions of "response" in studies of predictive factors, (b) the importance of compliance with treatment, (c) the potentially confounding issues of severity of illness and psychoticism in depression, (d) the status of chronicity of illness as a factor in prediction of treatment response, and (e) the possible value of a definition of "atypical depression" for differential selection of treatment.

Antidepressive Agents↗
PubMed1987

[General concepts of alpha-fetoprotein (AFP)-secreting tumors, with special reference to the histogenesis].

Recently, in addition to yolk sac tumors (YST) and hepatocellular carcinomas, many AFP-secreting tumors have been reported. A comparative morphological study of YST to the human yolk sac has revealed tumor cells mimicking the behavior of the human yolk sac endodermal cells (HYSEC). Another investigation suggests that an embryonal carcinoma (adult type), a gastric adenocarcinoma, or an ovarian adenocarcinoma, each showing no histologic features specific for YST, have a selective differentiation to HYSEC which can secrete an increased serum AFP. These tumors might well be called endodermal cell tumors. The histogenesis of AFP-secreting tumors can be attributed to the endodermal origin (or retrodifferentiation to the HYSEC).

Female↗
PubMed1987

The detection of basal cell determinants in human basal cell carcinomas using two different monoclonal antibodies.

This report deals with the reaction pattern(s) of two monoclonal antibodies (MoAbs) with normal skin and basal cell carcinomas (BCC). Using indirect immunoperoxidase (IIP) and indirect immunofluorescence (IIF) techniques, MoAb 12 G7 was observed to react with a determinant related to the cell membrane of the epidermal basal cells. In the IIP technique MoAb 12 G7 showed a positive reaction with 32 out of 34 BCC (94%), while in IIF all the 14 BCC that were studied were positive. In most cases only the cells at the periphery of the tumour nests were stained. MoAb 253 B7 reacted with cytoplasmic determinant(s) of the epidermal basal cells both in the IIF as well as in the IIP techniques. Using the IIP technique only 5 out of 34 BCC (15%) showed a positive reaction with this MoAb. Four of the 5 positively staining tumours showed aggressive histological features. Using IIF technique only 2 out of 14 BCC were positive. The results presented in this communication are discussed with regard to the possible expression of selective differentiation and tumor-associated determinant(s) in BCC.

Adult↗
PubMed1989

IL-5-dependent conversion of normodense human eosinophils to the hypodense phenotype uses 3T3 fibroblasts for enhanced viability, accelerated hypodensity, and sustained antibody-dependent cytotoxicity.

Human peripheral blood-derived eosinophils were assessed for their viability, density, and functional properties after 7 days of culture with purified mouse IL-5 and mouse 3T3 fibroblasts. Whereas none of the eosinophils remained viable after 7 days of culture in the absence of IL-5, 38 +/- 12% and 61 +/- 14% (n = 6, mean +/- SD) of the eosinophils survived in the presence of 1 pM IL-5 alone or 1 pM IL-5 in the presence of 3T3 fibroblasts, respectively (p less than 0.05). Direct contact between the fibroblasts and the eosinophils was not needed for this enhanced IL-5-dependent viability. After 7 days, 66 +/- 7% (n = 6) of the cocultured eosinophils were viable when the two cell types were separated by a 0.4-microns filter. As assessed by density-gradient centrifugation after 7 days of IL-5 exposure, all of the original normodense eosinophils became hypodense. The time course of this conversion was accelerated by the presence of 3T3 fibroblasts. Enhanced helminthic cytotoxicity was maintained by the 7-day cultured eosinophils only if they had been cocultured with fibroblasts. Eosinophils killed 10 +/- 11% (n = 5), 48 +/- 17%, and 31 +/- 15% of the larvae when they were cultured for 7 days in IL-5 alone, in IL-5 in direct contact with 3T3 fibroblasts, or in IL-5 with filter separation of the fibroblasts and the eosinophils, respectively. The ability of IL-5 to induce progenitor cells to differentiate selectively into eosinophils, and of 3T3 fibroblasts to facilitate the IL-5-mediated conversion of normodense eosinophils to hypodense eosinophils with increased viability and antibody-dependent cytotoxicity suggests a role for both hematopoietic and tissue factors in determining the presence and pathobiologic function of activated hypodense eosinophils in patients with hypereosinophilic conditions.

Animals↗
PubMed1989

Origin and differentiation of human mitochondrial DNA.

A recent study of mitochondrial DNA (mtDNA) polymorphism has generated much debate about modern human origins by proposing the existence of an "African Eve" living 200,000 years ago somewhere in Africa. In an attempt to synthesize information concerning human mtDNA genetic polymorphism, all available data on mtDNA RFLP have been gathered. A phylogeny of the mtDNA types found in 10 populations reveals that all types could have issued from a single common ancestral type. The distribution of shared types between continental groups indicates that caucasoid populations could be the closest to an ancestral population from which all other continental groups would have diverged. A partial phylogeny of the types found in five other populations also demonstrates that the myth of an African Eden was based on an incorrect "genealogical tree" of mtDNA types. Two measures of molecular diversity have been computed on all samples on the basis of mtDNA type frequencies, on one hand, and on the basis of the number of polymorphic sites in the samples, on the other. A large discrepancy is found between the two measures except in African populations; this suggests the existence of some differential selective mechanisms. The lapse of time necessary for creating the observed molecular diversity from an ancestral monomorphic population has been calculated and is found generally greater in Oriental and caucasoid populations. Implications concerning human mtDNA evolution are discussed.

DNA, Mitochondrial↗
PubMed1989

Prediction of change in borderline personality disorder.

Prediction of change in borderlines is an important effort because it may illuminate the character of this tentatively defined, complex disorder. In future years the disorder will be defined differently in light of its network of relationships with other variables. Presently, the strongest predictors of change in borderlines are receipt of neuroleptics and presence of target symptoms that are affected by these drugs. Other drugs and other treatments may also be found to have a selectively differential effect in which case receipt of these drugs will also predict change but perhaps on other target symptoms. Preliminary evidence implicates monoamine oxidase inhibitors (MAOIs), lithium, and carbamazepine. Response to thiothixene has been found to be related to the patient's Minnesota Multiphasic Personality Inventory (MMPI) profile prior to treatment. Biological predictor variables studied in other disorders have been found to be abnormal in borderlines, but how these variables might relate to change has not been studied. The program of research that is necessary includes other drug treatments, nonphysiological treatments, family history, and personality variables.

Antipsychotic Agents↗
PubMed1989

[Selection of methods of detecting lactose-fermenting Salmonella strains and evaluating their usefulness for diagnostic studies].

Salmonella rods of subspecies I, lactose-fermenting were first isolated in Poland in 1980. They were isolated from a plus sample taken from a brain abscess of a child. Next strains were isolated from faeces of newborn and hospitalized children. Growth characteristic of colonies of lactose-fermenting Salmonella strains on selective-differentiating media (Mac Conkey's Levine, SS, Sołtys) recommended for inoculation of clinical material resembled Escherichia coli. So far these type of colonies were omitted in diagnostic examinations. Lactose-fermenting variants showed on Bismuth sulfate agar "Difco" (WB) typical for Salmonella growth pattern. They grew on this medium after 48 hr of incubation in a form of black, medium sized colonies, with some metallic brilliance and characteristic blackening of the medium undercolonies. Precise knowledge of biochemical properties of lactose-fermenting Salmonella allows to supplement so far used diagnostic scheme with additional tests permitting differentiation of lactose-fermenting variants of Salmonella from the other members of Enterobacteriaceae family. Taking into consideration biochemical variants in diagnostic procedure i.e. lactose-fermenting Salmonella, allowedns to isolate in the years 1983-1985 lactose-positive strains in 1305 out of 2773 (47%) individuals positive for S. agona. In 1987, 246 persons (28.3%) out of 869 with lactose-fermenting Salmonella of various serotypes were simultaneously infected with lactose-negative variant. Lactose-fermenting strains of Salmonella belonged most frequently to the following genera: S. agona, S. enteritidis, S. oranienburg, S. typhimurium, and S. goldcoast. It was found that the modified diagnostic procedure makes possible the isolation and the identification of lactose-positive varians of Salmonella.

Bacteriological Techniques↗
PubMed1989

[Practice of hygienic standardization of industrial allergens in the air of the work area and ways of its improvement].

Proceeding from the results of 8-year practical experience in hygienic standardization of industrial allergens (IA) in the workplace air it is pointed out that only substances for which sensitizing effect is a limiting criterion should be regarded as IA. It is demonstrated that IA are attributed to different hazardous classes according to which differential selection of safety factor is recommended. Highlighted is the necessity of developing new methods of IA hygienic standardization.

Air Pollutants, Occupational↗
PubMed1989

Immunogenetic studies of two recently contacted populations from Papua New Guinea.

We have examined the HLA profiles of the Hagahai and the Haruai people, two linguistic groups in the remote western Schrader mountains who have only recently had administrative contact, and compared them with those of other populations in Papua New Guinea. None of the antigens detected in the two groups was found missing in other populations although significant differences in allele frequencies exist. Recent contact history does not appear to have played any significant role in shaping these differences. Similarly, no evidence of differential selection pressures contributing to HLA heterogeneity was found. The genetic profiles of the Hagahai and the Haruai appear to be a result of recent admixture between unrelated, genetically disparate groups.

Culture↗
PubMed1989

[Effect of synoptic-meteorologic factors on the course of bronchial asthma in adolescents].

Asthmatic attacks observed in 1131 adolescents on sanatorium treatment are related to passing of atmospheric fronts. The attacks predominated in those patients who had come to the spa in condition of uncured bronchial asthma aggravation. As the episodes of asphyxia prevent the asthmatic adolescents from benefits of spa factors it is necessary to perform more differentiated selection to sanatorium treatment.

Adolescent↗
PubMed1989

[The motor regimen for myocardial infarct patients at the stage of hospital treatment].

Long-term observations are presented in a differentially selected group of patients with macrofocal and transmural myocardial infarction subjected to an extensive program of motor exercises during hospital treatment. Results of rehabilitative treatment proved better in this group in the long-term follow-up. Hospitalization time was reduced approximately in 1/6 of patients with macrofocal and transmural myocardial infarction.

Adult↗
PubMed1985

Providencia stuartii: a search for its natural habitat.

A selective differential medium has been used to search for Providencia stuartii in sewage, sewage contaminated natural waters and the faeces and skin of a small population of healthy non-hospitalized males. Colonization of 12 male patients with long-term indwelling bladder catheters and the general environment of the spinal injury unit was also examined. Providencia stuartii was not isolated from the non-hospital samples, but colonization of the urine (two patients) faeces (five patients) and skin (eight patients) was observed. Apart from equipment that had been in contact with patients urine or skin there was no general contamination of the ward environment suggesting that colonized patients were the main reservoir of this multiply antibiotic-resistant nosocomial pathogen.

Bacteriuria↗
PubMed1985

[The role of organization measures in the early detection of lung cancer during mass screening].

The experience gained in fluorographic mass screenings for early detection of lung cancer in Rostov Region showed their effectiveness to depend on differential selection of population study groups on the basis of examination periods determined according to the data of local registries, formation of high risk groups on the basis of the suggested criteria, and further research in the rhythm of fluorographic screenings in different population groups. Practical aspects of mass screenings deserve more attention. The percentage of lung malignancies detected in the course of mass screenings increased as a result of taking certain effective organizational measures, thus making the case for further research into the problem.

Adult↗
PubMed1986

Charge effect on binding, uptake and transport of ferritin through fenestrated endothelium.

The binding, uptake and transport of hydrosoluble macromolecules as a function of their electric charge have been investigated in mouse pancreatic exocrine fenestrated endothelium. After intravenous injection of ferritin derivatives with different isoelectric points (3.7, 4.5, 7.0 and 8.4) specimens of pancreas were collected at 5, 25, 45 and 60 min and processed for electron microscopy. Although the concentrations (10 mg/ml) and injected volumes (1 ml/100 g body weight) were identical, the tracers with similar molecular weight (Mr approximately 960,000), but with different net electric charge, followed different routes in endocytotic and transcytotic processes. The endothelial cell internalizes ferritins into multivesicular bodies and lysosomes. While anionic ferritins are endocytosed via plasmalemmal vesicles (fluid phase endocytosis), the cationic derivatives are taken up exclusively by coated pits (adsorptive endocytosis). The anionic and neutral macromolecules seem to be transcytosed via plasmalemmal vesicles. The circulating polycations are aggregated by plasma proteins and transcytosed as such either in fluid phase by large vacuoles, or by adsorption on the coated structures. The first mechanism is physiological, the latter probably appears in unusual conditions by which the endothelium participates in the plasma clearance. Our findings indicate that, for the transport of macromolecules, the capillary endothelium can be accounted not only as a size barrier but also as a selective-differentiated charge barrier with complex and multiple mechanisms for the modulation of its transport systems. The endocytotic and transcytotic processes undergo the effect of net electric charge of the plasma components.

Animals↗
PubMed1988

[Peculiarities of physical therapy in endangiitis obliterans].

The particularities of the physiotherapy in the obliterating endangiitis in the framework of the treatment of arterial occlusive diseases consist in the differentiated selection of the remedies of physiotherapy and their adequate, i.e. often slight dosage. The interval at stage I and II after Fontaine free of inflammation should be used. The physiotherapy of the obliterating endangiitis possesses adjuvant character and thus supplements the reasonable polypragmasy of the whole concept of therapy.

Combined Modality Therapy↗