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At least 127 records · Page 7Linked to original sources
PubMed1966

Antibody production by cells in tissue culture. I. Morphological evolution of lymph node and spleen cells in culture.

An organ culture technique was used to investigate the migration and the morphological evolution of lymphocytes from lymphopoietic tissues. This evolution was compared with the behavior of cells extracted from the tissue and kept in nutritive medium in vitro. It was found that cells were continuously migrating from the fragments of lymph nodes or spleen, and were attaching to the glass. They spread on glass, their protoplasm enlarged and their nucleus became clearer. The evolution towards blastoid cells was identical with that described under artificial stimulation by PHA for example. Cytological identification of the cells actively engaged in antibody synthesis (as detected by local hemolysis in gum) at the time of staining, showed that several distinct cellular types were active, including plasma cells and macrophagelike cells. It is assumed that the stimulated lymphocytes, after spontaneous migration from the tissue are able to evolve into an "immunoblast" stage and then, eventually after fixation upon a physical support, to initiate antibody synthesis.

Antibody Formation↗
PubMed1987

Basic studies of hydrogen evolution by Escherichia coli containing a cloned Citrobacter freundii hydrogenase gene.

Citrobacter freundii genes that complemented Escherichia coli hyd-(hydrogenase activity) mutation were cloned in plasmids pCBH4 (6.2 kb) and pCBH6(5.7 kb). Hydrogen evolution by the transformant E. coli HK-8(pCBH4 or pCBH6) was investigated. The optimum culture temperature of recombinant E. coli cells for hydrogen evolution from glucose was in the neighborhood of 18 degrees C. The recombinant E. coli cells cultured at this condition showed a several-fold increase of hydrogen evolution, as compared with that of the wild-type cells. The plasmid-retention stability of this recombinant E. coli was extremely high, especially plasmid pCBH4, which was completely retained during 2 wk without any restriction. Hydrogen production by immobilized recombinant E. coli was then investigated using cells cultured at 18 degrees C. The hydrogen evolution rate from glucose and Lennox-broth were about twofold higher than that of E. coli C600, and this high hydrogen evolution rate was maintained for more than 1 mo.

Citrobacter↗
PubMedDate not supplied

[Fibrous fixed subaortic stenosis].

Fifty eight patients with isolated with discrete subaortic stenosis or in association with just another heart defect, were studied between 1961 and 1980. The age range was between 2 and 42 years. The evaluation of each case was done according to clinical manifestations, systolic overloading of the left ventricle and the amount of the systolic gradient. There is a poor correlation between the clinical, electrocardiographic and hemodynamic parameters according to the student t test in the preoperative evaluation. Forty-one patients were operated, two of them died in the early post-operative period. There was a good clinical evolution with significant values comparing pre and post-operative symptoms. The decrease in the systolic gradient in 26 cases after surgery was significative (p less than or equal to 0.005). Based on the natural history of this malformation and on the results obtained with the surgical treatment, we may conclude that there is surgical indication once the diagnosis is made, because this malformation has a completely different evolution compared with other forms of congenital aortic stenosis.

Adolescent↗
PubMed1990

[Quantitative analysis of the teleost brain: evolution and adaptation. 1. A comparative interspecies study].

The intraspecific brain-body weight allometric coefficient, although high in Teleosts (0.49), is different enough from the interspecific one (0.65, almost 2/3) to use only adult specimens for quantitative studies. The low encephalization level of species of great size makes the use of a quadratic curve preferable, although not well adapted to small species. The mean variability of encephalization indices within the species is 8%. Differences of encephalization are noted either between sexes (Misgurnus fossilis) or between ecological milieus (Ictalurus melas). The variability increases progressively from species to genus, family and order; the allometric coefficient grows also, following the general trend for a larger encephalization when the body size is greater. The correlation between the encephalization index and the position within the classification is low; the great number of exceptions makes it necessary to look for other biological and ecological factors, such as the body form, the type of locomotion, the general activity level, the food habits, the way fishes avoid predation and social organization. The index value is due either to the modification of the body size (overweight due to the elongated form of the body, the ballast of poor diets: limivores, coral or sponge eaters, the passive protection against predators of thick scales, spines, etc), or to that of the brain size. In that case, a better encephalization is to be noted in species with a fusiform body, swimming with lateral beats of the caudal peduncle, in active species from mid-waters or pelagic, in predators actively hunting their prey, in species using active ways of protection against predation, in diurnal fishes and in those which have a social way of life needing a good knowledge either of their milieu (territorial behaviour) or of their congeners (social behaviour).

Animals↗
PubMed1992

[Pregnancy in adolescents. Complications, birth weight, somatometry of the newborn and Apgar score, comparison with the general population].

The objective of this study was to compare pregnancy evolution, newborn's weight, its somatometry and Apgar's qualification of teenagers and the general population in a community where the socio-economic factor is similar among those two groups. Three hundred and two pregnancies in teenagers were analyzed, 69 of 12-15 years and 233 of 16-17 years at the time of pregnancy, against a control group of 304 pregnant patients of 18-39 years. It was a prospective, comparative, longitudinal study. Average age at the first delivery of the 606 patients was 18.1 years. There were no significant difference among the groups as to occupation. There was not significant difference among the three groups as to pre-natal control, weeks of gestation incidence of threatening abortion, toxemia, bleeding of the second half of pregnancy, premature rupture of membranes, proportion of deliveries and cesarean sections, as well as forceps application and newborns' sex. The most common indications of cesarean section in teenagers were CPD and acute fetal suffering, in the control group were CPD and pelvic presentation. There was significant difference comparing the weight, Apgar qualification at one minute and at three minutes in the 16-17 years group, and older of 18 years being greatest in the last group. There was significant difference in size, cephalic perimeter, thoracic perimeter and PC/pa ratio among the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

Probing fungal mitochondrial evolution with tRNA.

Sequence data are now available for almost the entire complement of mitochondrial rRNAs from five fungi: Schizosaccharomyces pombe, Saccharomyces cerevisiae, Toropulis glabrata, Aspergillus nidulans and Neurospora crassa. Analysis of these data show that the five mitochondria can be related to a common ancestor. The unusually high similarity between some S. pombe mt tRNAs may be due to a process similar to gene conversion. Using the number of differences between tRNA pairs as a measure of the evolutionary rate the yeast-S. pombe branch has paradoxically a high nuclear rate and a low mt rate of evolution as compared with other branches in the phylogenetic tree. Finally the position of mt tRNA genes in S. pombe is abnormally distinct from gene orders in other mitochondria. All of the above factors must be taken into account when describing the relationship between these mitochondria.

Base Sequence↗
PubMedDate not supplied

[Hormone dependence in functional thyroid cancers, survival after total thyroidectomy combined with radioactive iodine and thyroid extract therapy].

The authors reviewed current criteria on hormone-dependence in functional thyroid cancers, presenting data of compared disease evolution based on the casuistics of thyroid carcinomas from the files of the Fundación Jiménez Díaz, with 5 and 10 year follow-up studies in some of the cases. They found a higher number of survivors among the patients with papilliferous carcinoma in both 5 and 10 year follow-up groups whom, aside total surgical removal of the gland and the administration of thyroid extracts, those who had thyroid residues left were given 100 mc of 131I. Among the patients with follicular adenocarcinoma, under the same comparative conditions, differences were not very clear in the 5 year follow-up group, while the 10 year follow-up group showed marked differences. The authors conclude that an adequate combination of the three therapeutic procedures may allow a higher survival rate.

Adenocarcinoma↗
PubMed1984

The spread of sequence variants in Rattus satellite DNAs.

The genus Rattus has two related families of satellite DNA: Satellite I consists of tandem arrays of a 370 base pair repeat unit which is a dimer of two 185 base pair portions (a, b) which are about 60% homologous. Satellite I' consists of tandem arrays of a 185 base pair repeat unit (a') which is about 85% homologous to a and 60% homologous to b. R. norvegicus contains only satellite I but R. rattus contains both satellites I and I'. We examined certain aspects of satellite DNA evolution by comparing the spacing at which variant repeat units of each satellite have spread among non-variant repeat units in these two species. With but one exception, in R. rattus, 15 different variant repeat units have spread among non-variant repeat units of satellite I, with a spacing equal to the length of the (a,b) dimer. Similarly, fourteen different variant repeat units of the monomeric satellite I' have mixed among non-variant repeat units with a spacing equal to the length of the (a') monomer. These results suggest that a mechanism involving homologous interaction among satellite sequences could account for the spread of variant family members. We also found that a sequence variant present in certain portions of the dimeric repeat unit of satellite I is more efficiently amplified (or less efficiently corrected) than variants occurring in other regions. This was not true for the monomeric repeat unit of satellite I'.

Animals↗
PubMed1979

[Evaluation of mechanical ventilation in meconial aspiration syndrome].

Twenty seven newborn with serious meconial aspiration syndrome are studied. Two groups are stablish weather they require or not mechanical ventilation during evolution. When comparing various perinatal and clinical data, only the Silverman test showed statistically significant differences; pH and gases in blood during the first hours of life did not showed differences. Pneumothorax incidency in both groups was 33%. Twelve newborn required mechanical ventilation. The starting age was 24 hours of life range 3-54 hours. Most frequent indication was hipoxemia and apnea. Use of intermitent positive pressure improved PaCO2 with a light increase in PaO2 though it also increased alveolo-arterial oxygen gradient. Hipoxemia was the most relevant data in evolution of these patients. In seven cases continuous distending pressure was applied, with a light increase in PaO2 only in three patients. No patient suffered pneumothorax during mechanical ventilation. In patients with mechanical ventilation mortality was 25%. The possibility of an addition in certain cases of pulmonary hypertension with right-to-left shunting ductal and atrial is reported.

Age Factors↗
PubMed1982

Comparative morphological features of the caecilian inner ear with comments on the evolution of amphibian auditory structures.

Comparative fine structural studies of amphibian auditory structures in urodeles have been extended to include examination of the papilliform end-organs (amphibian, neglecta and basilar) that variably occur in species selected from three families of caecilians (Gymnophiona). The species investigated were Ichthyophis kohtaoensis (Ichthyophiidae), Dermophis mexicanus (Caeciliidae) and Typhlonectes natans (Typhlonectidae). Ichthyophis is the only form to display all three papillae; both Dermophis and Typhlonectes lack a basilar papilla but all three species show both neglecta and amphibiorum. In these forms, the amphibian papilla contained the most sensory cells with ciliary bundles organized into two proximal and distal groups polarized toward a mid-line papillar axis. The papilla neglecta contained slightly fewer sensory cells and ciliary bundles oriented predominantly posteriorly. In Ichthyophis, the basilar papilla contained the lowest sensory cell counts of any papilla. Here, basilar sensory cilia were unidirectionally polarized away from the saccule. All papillae were overlain by an essentially similar, extracellular tectorial body. When compared to auditory end-organs in the urodeles and anurans, similar conditions in caecilians are suggestive of a common ancestry for the basilar and amphibian papillae; features of the amphibiorum indicate further that it may represent part of a "displaced" papilla neglecta.

Amphibians↗
PubMed1987

Molecular studies of marsupial X chromosomes reveal limited sequence homology of mammalian X-linked genes.

To explore the extent to which the X chromosome has been conserved during mammalian evolution, we compared six loci that are X-linked in the human genome with the corresponding genes of the North American marsupial, the Virginia opossum (Didelphis virginiana). Our analysis shows that in the opossum genome there are sequences highly homologous to those of human cDNAs for housekeeping genes, glucose-6-phosphoribosyltransferase (HPRT), phosphoglycerate kinase A (PGK1), and alpha-galactosidase A (GLA). However, ornithine transcarbamylase and blood clotting Factor IX--tissue-specific genes that are X-linked in eutherians mammals--have no highly conserved homologs in the marsupial genome. By cloning opossum G6PD and HPRT, we found that these genes are X-linked in the opossum and that homologous sequences are limited to coding regions. As all genomic fragments hybridizing with the human GLA probe show dosage effects, it is likely that the opossum counterpart is X-linked. Finally, the pattern of hybridization suggests that the autosomal pseudogenes of HPRT and PGK1 in the opossum have remained highly homologous to the human X-linked genes.

Animals↗
PubMed1992

[Adverse prognostic influence of diabetes mellitus and hyperglycemia on the clinical course of cerebral infarction].

We accessed the potential impact of diabetes mellitus and hyperglycemia on early prognosis in a study of 109 cases of CT proved brain infarction. Main end-points of this study were 30-days case-fatality rates and the probability of early discharge or prolonged hospitalization. Proportions of patients exhibiting diverse evolutions were compared by Fisher's test and, when the number of observations permitted, by chi-square test. Diabetes mellitus was diagnosed by history in 15.6% (17 patients). In 86 cases analysed within 72 hours of admission, hyperglycemia (glucose level higher than 110 mg/dL) was detected in 67.4% (including all 14 diabetic patients (35.3% vs 21.7%; p = 0.18), but these patients probably were discharged early less frequently (23.5% vs 51.1%; p = 0.06). Compared to the normoglycemic patients, hyperglycemic patients also fared worse, when considering altogether the early discharge and case fatality rates and the need for prolonged hospitalization (p = 0.06). They also exhibited a nonsignificant increase in early case fatality rate (31% vs 15.4%; p = 0.21) and a markedly reduced chance of obtaining early hospital discharge (37.9% vs 65.4%; p = 0.03). Case fatality rates were maximal in diabetic hyperglycemic patients (42.9%) and seemed intermediate in non-diabetic hyperglycemic patients (27.3%). Considering the three end-points evaluated, the apparent differences between non-diabetic hyper and normoglycemic patients did not reach statistical significance (p = 0.19). These results suggest that both diabetes mellitus and hyperglycemia "per se" have deleterious effects on the clinical evolution of patients with cerebral infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1979

[Walker's 256 carcinosarcoma: metastatic dissemination in two cell lines (author's transl)].

Walker's 256 carcinosarcoma a transplantable tumor of the rate changes its behaviour as a consequence of various factors. In this paper we compare the evolution of 2 lines of the tumor: WM 16 (muscular) and Christ Hospital (ascitic) both inoculated intramuscularly. Animals receiving line WM 16 had a severe rapidly progressive evolution dying around day 14 after inoculation with diffuse metastases to lymph nodes (65% of animals), kidneys (53%), spleen (50%), lungs (46.5%), liver (45%), bone marrow (44.8%), in 56% of the animals there were circulating tumoral cells. Animals receiving Christ Hospital line survived up to 40 days, metastases were limited do lungs (48.7%) and lymph nodes (31.7%) and only in 2 of 45 animals circulating tumoral cells were observed.

Animals↗
PubMed1987

[Acute myocardial infarction. Different treatment, different prognosis?].

Many statistics demonstrate a definite improvement of myocardial infarction during hospitalization, especially a decrease in the mortality. It appears tempting to credit that improvement to the numerous modifications of the treatment of this dangerous disease in the last few decades. The study reported here indicates, however, that other factors must be taken into account. We compared the evolution of two groups of patients hospitalized for acute myocardial infection, 10 years apart: The first group (G1) of 731 patients corresponds to years 1970-1975; the second group (G2) of 729 patients, corresponds to the years 1984-85-86. During these ten years, mortality decreased by 38 p. cent, from 19.2 p. cent (G1) to 11.9 p. cent (G2). This decrease remains significant regardless of age and sex, except in two subgroups with the least number of patients, i.e. women under the age of 65 and men over 65. It should be noted that rhythm disorders occur with the same frequency in both sub-groups while atrio-ventricular blocks seem to have decreased. The difference in the mortality cannot be attributed to the patient's selection. In fact, in both groups, they are comparable regarding the men/women ratio, the age distribution and the presence of main risk factors (tobacco abuse, dyslipidemia, arterial hypertension, diabetes, heredity). The treatment results in many alterations especially concerning diuretics which seem to be used in approximately 30 p. cent of the patients in both groups. On the contrary, steroids, prescribed in 25.3 p. cent of G1 patients are abandoned; electro-systolic stimulation established in 21.2 p. cent of G1 patients, concerned only 4 p. cent of G2 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1990

Large sequence divergence among mitochondrial DNA genotypes within populations of eastern African black-backed jackals.

In discussions about the relative rate of molecular evolution, intraspecific variability in rate is rarely considered. An underlying assumption is that intraspecific sequence differences are small, and thus variations in rate would be difficult to detect or would not affect comparisons among distantly related taxa. However, several studies on mammalian mitochondrial DNA (mtDNA) have revealed considerable intraspecific sequence divergence. In this report, we test for differences in the rate of intraspecific evolution by comparing mtDNA sequences, as inferred from restriction site polymorphisms and direct sequencing, between mtDNA genotypes of the eastern African black-backed jackal, Canis mesomelas elongae, and those of two other sympatric jackal species. Our results are unusual for several reasons. First, mtDNA sequence divergence within several contiguous black-backed jackal populations is large (8.0%). Previous intraspecific studies of terrestrial mammals have generally found values of less than 5% within a single population, with larger divergence values most often occurring among mtDNA genotypes from geographically distant or isolated localities. Second, only 4 mtDNA genotypes were present in our sample of 64 jackals. The large sequence divergence observed among these mtDNA genotypes suggests there should be many more genotypes of intermediate sequence divergence if they had evolved in sympatry. Finally, estimates of the rate of mtDNA sequence evolution differ by approximately 2- to 4-fold among black-backed jackal mtDNA genotypes, thus indicating a substantial heterogeneity in the rate of sequence evolution. The results are difficult to reconcile with ideas of a constant molecular clock based on random fixation of selectively neutral or nearly neutral mtDNA sequence mutations.

Africa, Eastern↗
PubMed1989

Course of psychosis in Algeria and in France: about 342 cases observed from 1975 to 1985.

The aim of this study was to compare the evolution of psychotic patients in Algeria and in France. In 1975, 105 patients were selected in Algeria and 237 in France. Ten years later, in 1985, all these patients were interviewed. In 1985, we investigated for each subject the evolution of the following parameters: sex, age, DSM-III axis 1 and 5, marital status, social welfare work, and treatment variables. Our results indicate that the improvement of the psychosocial adaptation (DSM-III axis 5) is slightly better in Algeria than in France. Medical and social support seems to be quantitatively less important in Algeria.

Adult↗
PubMed1983

The influence of gut function on lymphoid cell populations in the intestinal mucosa of lambs.

The number and type of lymphoid cells in the intestinal mucosa of lambs change during the first weeks after birth. The influence of gut function on these changes was examined by comparing the evolution of lymphoid cell populations in normal ileum with that in lengths of ileum which had been isolated surgically from the functional intestinal tract of the lamb before birth. The isolated lengths of ileum had a normal blood and nerve supply and they remained healthy throughout a period of at least 2 years, although they did not have a normal histological development. In comparison with normal ileum, the villi of the isolated ileal segments were much smaller and there were many fewer intraepithelial lymphocytes; the lamina propria had significantly fewer lymphocytes than the functional ileum and only a few plasma cells. When isolated ileal segments were reconnected into the intestinal tract after having been isolated from it for 1-3 months, the histology of the mucosa reverted to that of the normal gut, with the same number and types of lymphoid cells. Radiolabelled lymphoblasts collected from intestinal lymph and injected intravenously accumulated to only a small extent in isolated segments of ileum compared with either the normal or the reconnected segments of ileum. This suggested that the paucity of lymphocytes in the mucosa of the isolated segments was due to a reduced extravasation of these cells there. The influence which the gut contents exert on the lymphoid cell population in the mucosa is probably associated with antigenic stimulation but may also be related to other factors concerned in the normal digestive functions of the gut.

Animals↗
PubMed1975

[Research in sociotherapy].

The author compares his experience in two psychiatric institutions: an old one of the traditional type, a new one of the psychotherpeutic type. He tries and defines the role of the different members of the staff and compares the evolution of the traditional institute and of the more recent clinic. In the psychotherapeutic institution, there is a drift of the therapeutic role from the physician to the nurse, and finally from the nurse to the patient himself. Despite the fact that they are open, the therapeutic groups become more efficient with time in relation to the maturation of the nursing personal. This slow growth of the psychotherapeutic role of the institutional group finally depends as much on the inhibitions of the nursing staff than on the anxiety of the patients.

Hospitalization↗