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At least 19 recordsLinked to original sources
PubMed1978

Thyroid and obesity: survey of some function tests in a large obese population.

Tests of thyroid function in 493 obese patients were compared with thyroid function in 3076 non-obese patients. No differences in 131I uptake by the thyroid were observed at 6 h or 24 h; the frequency distribution was gaussian or normal in both populations; the frequencies of normal, high or low T3 and T4 values in the two populations were likewise comparable. Further, no correlation was found in the obese subjects between 131I uptake (6 h and 24 h), T3, T4 and overweight; on the other hand, there was a significant negative correlation between 131I uptake (6 h and 24 h) and age. It would appear that thyroid function is normal in obesity.

Adolescent↗
PubMed1979

Seasonal variation in work performance and heart rate response to exercise. A study of 1,835 middle-aged men.

A near maximal bicycle exercise test in 1,835 presumably healthy Norwegian men indicated a seasonal variation in physical fitness. Thus, the total amount of work performed was significantly higher, and the work pulse on equivalent loads significantly lower during the summer than during the autumn. Although the differences were small, they may invalidate comparisons made between exercise tests in populations tested at different seasons of the year. In particular, there was a considerable and sudden change in the above mentioned parameters from June--August to September--October.

Adult↗
PubMed1979

Limitations of psychological tests in a dialysis population.

Psychological tests are being used increasingly in dialysis populations, both for psychosomatic research and for clinical evaluations, warranting careful examination of their uses and limitations. Characteristics associated with dialysis populations can limit the validity of many psychological tests which are useful in other populations. These characteristics include such factors as the great biological heterogeneity of dialysis patients, their uniquely dependent relationship to treating staff, and their tendency to respond with socially desirable answers. There is a need to develop psychological tests that are specific for dialysis populations and take into account social desirability response bias. At present, the limitations of psychological tests in a dialysis population are substantial.

Attitude↗
PubMed1979

Further studies on the compatibility between s. intercalatum from cameroun and zaïre and species of bulinus.

The results from the infection experiments with Schistosoma intercalatum from Cameroun and from Zaïre and the intermediate hosts, belonging to B. forskalii and B. globosus, could be divided into groups according to the degree of compatibility with the schistosomes. This was indicated by the total cercariae production per 100 exposed snails (TCP/100 exp. snails). B. forskalii from Kinshasa, Zaïre were the snails which were most compatible with S. intercalatum from Cameroun, and B. globosus populations tested were refractory. The TCP/100 exposed snails was about 300,000 for the populations of B. forskalii from Kinshasa compared with the low production for B. forskalii from Cameroun of 125,000. B. wrighti from South Arabia produced 155,000 cercariae per 100 exposed snails. B. cernicus from Mauritius could be separated into two types according to the compatibility with S. intercalatum from Cameroun, the TCP/100 exposed snails was 31,000 and 267,000, respectively. B. globosus from Kinshasa, Zaïre, was very compatible with S. intercalatum from Zaïre and the TCP/100 exposed snails was very high, and 300,000. An albino strain of B. globosus from Rhodesia was the most compatible snail having a TCP/100 exposed snails of 2.4 million cercariae. Other strains of B. globosus from Cameroun and Togo were refractory and less susceptible. It was also possible to infect B. africanus and the two tested populations from Kenya and Tanzania, producing 15,000 and 179,000 cercariae per 100 exposed snails, respectively.

Africa↗
PubMed1979

[Genetic markers and disease susceptibility (author's transl)].

The HLA system includes several genes and each of them is polymorphic. Several associations between some HLA alleles and the susceptibility to various diseases are already described. Three kinds of associations are reported: [1] a constant association between an HLA allele and a disease whatever the tested population, [2] an association between the HLA allele and a disease varying according to the tested populations, [3] an association probably due to a mutation of metabolic gene closely linked to HLA. These three kinds of associations probably correspond to three different mechanisms.

Alleles↗
PubMed1976

X-ray-induced recessive lethal mutations in the mouse.

A test of X-ray-induced recessive lethal mutations in mouse spermatogonia (500 rad) was carried out. The test was based on familial analysis, which allowed division on the P pairs into those with lethal heterozygous members and in others assumed to be lethal-free. The F1 males from the latter group, in back-crosses to their daughters, gave an excessive rate of intra-uterine death in comparison with lethal-free males. The excessive death is assumed to reflect the rate of new (induced + spontaneous) recessive lethals or rather lethal equivalents. Three ways of estimating the rate of new recessive lethal mutations gave a mean of 5.5% per genome. From the previous tests we can assume that 1% are spontaneous mutations. Thus the data indicate that the mutation rate per rad per gamete is 9 X 10(-5). This value is identical with a previous estimate. The results are discussed in relation to population tests performed in the early 60's. It is concluded that the lack of observable deterioration in the populations after several consecutive generations of exposure is in accord with the estimates in the present analysis which are more than an order of magnitude lower than assumed at the start of the population tests. It is also stressed that species with different DNA contents show similarities in point estimates of doubling dosages.

Animals↗
PubMed1979

Statistical design of toxicity assays: role of genetic structure of test animal population.

This paper concerns certain statistical aspects of the problem of among-strain differences in cancer susceptibility and how these differences may affect the design of toxicity assays. First, the data of Innes et al. (1969) were examined to investigate the magnitude of within-study, between-strain differences in tumor induction. Although there was a very high overall association between mouse strains with respect to the induction of hepatomas, evidence of strain-to-strain variability was found for several compounds. Next, a number of long-term carcinogenicity studies with DDT were considered, and among-strain differences in cancer susceptibility for this compound were noted. Finally, it was shown that if susceptible subgroups do exist, and certain simplifying assumptions are made, then in many cases tumor increases can be detected more readily by studying several inbred mouse strains rather than a single outbred stock.

Animals↗
PubMedDate not supplied

Statistical design of toxicity assays: role of genetic structure of test animal population.

This paper considers certain statistical aspects of the problem of among-strain differences in cancer susceptibilities and how these differences may affect the design of toxicity assays. First, in order to investigate the magnitude of within-study, between-strain differences in tumor induction, the data of Innes et al. (1969) were examined. It was found that although there was a very high overall association between mouse strains with respect to the induction of hepatomas, several compounds showed evidence of strain-to-strain variability. Next, a number of long-term carcinogenicity studies with DDT were considered, and among-strain differences in cancer susceptibility for this compound were noted. Finally, it was shown that if susceptible subgroups do exist and certain simplifying assumptions are made, then in many cases tumor increases can be detected more readily by using several inbred mouse strains for study rather than a single outbread stock.

Animals↗
PubMed1978

Cell surface antigens detected on mature and leukemic granulocytic populations by cytotoxicity testing.

Using a microcytotoxicity assay, the serological reactivity of human granulocytes, namely neutrophils and eosinophils, and chronic myeloid leukemia (CML) cells and cultured CML cell lines (K562, NALM-1) were examined. Mature granulocyte forms and cord granulocytes are readily lysed by specific granulocyte cytotoxins that do not react with random T and B lymphocytes, monocytes, red blood cells, or platelets. Furthermore, certain antisera were preferentially cytotoxic for eosinophil-enriched populations. Granulocytotoxin detected antigens on one of three CML blast cell populations tested and K562, but failed to react with NALM-1. By cytotoxicity, mature granulocytes were poor targets for B2-microglobulin and the appropriate HLA antisera although both sera types are absorbed with granulocytes. Furthermore, granulocytes did not possess B-lymphocytes (Ia-like) or blood group A, B, and Rh (D) antigens. Except for K562, both HLA and heterologous B-lymphocyte antisera were cytotoxic for the CML blast cell populations tested.

ABO Blood-Group System↗
PubMed1977

A suppressor mechanism controlling lymphocyte recruitment.

The duration of the inductive effect of an antigen (alum-precipitated trinitrophenyl-keyhole limpet haemocyanin) was measured, in the presence and absence of responding spleen cells, by transfering a test population of spleen cells to irradiated mice at various times relative to antigen injection. Using allotype-congenic mice, the response of a test (Iga) population was estimated in the presence of responding (Igb) cells. In the absence of responding cells the inductive effect fell to 10% of the peak value in 9-10 days, but in their presence it reached this level in less than 5 days. Removal of T cells from the responding (Igb) population reduced their suppressive efficacy. It was concluded that B lymphocyte recruitment is curtailed not by the elimination of antigen but by an active suppressor mechanism involving suppressor T cells.

Animals↗
PubMed1979

Immunogenic complexes obtained from Salmonella typhi-murium and Salmonella typhi Ty2 by the bacterial acetone powder method.

An immunogenic complex was isolated from Salmonella typhi-murium and another one from Salmonella typhi Ty2. Both were prepared by the bacterial acetone powder method which eliminated the cell wall, the DNA almost completely and the membrane phospholipids. The complexes were denominated "New Vaccines". The S. typhi-murium new vaccine induced, even at doses of 0.5 microgram dry weight per mouse, a high degree of protection against the challenge of the virulent microorganism. By immunoelectrophoresis, 21 antigen-antibody systems could be detected, two of them corresponding to O antigens. The S. typhi Ty2 new vaccine induced better protection than the standard vaccine (heat-phenol inactivated typhoid vaccine) when both vaccines were compared in the relative potency test. Moreover, the new vaccine had very low toxicity when inoculated in humans at doses of 1 microgram dry weight, able to elicite a high antibody titre (1/1,790 mean of 10 sera) in 75% of the tested population, estimated by the complement fixation test. In contrast, the standard vaccine induced a low antibody titre (1/222, mean of 5 sera) in 50% of the humans inoculated with 1 X 10(8) bacterial cells. The new vaccine did not induce undesirable effects whereas the standard vaccine induced an important inflammatory process in 100% of the cases, with intense local pain in 67% after 24 h post-first inoculation as well as other less severe symptoms.

Acetone↗
PubMed1979

Nickel sensitivity in the general population.

The incidence of nickel sensitivity in a population above the age of 10 was examined through epicutaneous tests with 5% nickel sulphate performed on certain school and occupational test subjects and on subjects at a home for elderly people. Nickel sensitivity was observed in 4.5% (in 44 cases of 980 tested subjects), in 8% of the females and in 0.8% of the males. In 42 of the 44 nickel-sensitive subjects there was a history of dermatitis from metal contact. At the time of testing, 16 (34%) of the nickel-sensitive subjects revealed eczema. A manifest nickel sensitivity was thus found in 1.6% of all tested subjects, in 2.8% of females and in 0.4% of males. Nickel sensitivity and a simultaneous hand eczema was noted in 0.9% of the tested population, in 1.6% of females and in 0.2% of males. Hand eczemas were rarer (20.5%) in the nickel-sensitive subjects in the population study than in the nickel-sensitive patients tested at the same time in the clinic (56.6%). No case of nickel sensitivity was occupationally related.

Adolescent↗
PubMed1978

A comparison of the genetic infrastructure of the Ye'cuana and the Yanomama: a likelihood analysis of genotypic variation among populations.

A general procedure is described for measuring and testing population differences in gametic frequencies. The total dispersion among populations is subdivided in hierachical fashion. The multiple-locus treatment is simply the sum of the single-locus analyses, provided gametic equilibrium obtains among the loci. In the event that gametic equilibrium does not obtain, correlations among loci need to be dealt with.--The analysis is then used to examine the genetic infrastructure of two Indian tribes from South America, the Ye'cuana (Makiritare) and the Yanomama. From historical evidence, we may identify several "clusters" of villages within each tribe. The demographic and cultural practices affecting village formation and the maintenance of peer integrity are rather different in these tribes, however, and lead us to postulate rather different patterns of genetic variation among villages. Analyses of five codominant two-allele loci, four dominant two-allele loci and two complex loci (with four codominant haplotypes each) demonstrate that Yanomama clusters are more disparate than Ye'cuana clusters, as would have been predicted on sociocultural grounds.

Blood Group Antigens↗
PubMed2026

Brazilian Society of Surgical Oncology Analysis in Cost-Effectiveness of Population-Based BRCA Testing for Ovarian Cancer in the Public Health System.

Although ovarian cancer is the most lethal among gynecological cancers, access to massive BRCA testing is still limited. Its cost-effectiveness is still a topic of discussion in several countries. In Brazil, olaparib was recently incorporated into the public health system, access to BRCA testing is still limited. In this article, we aim to review the cost-effectiveness of offering BRCA testing to the at-risk population. A working group composed of 14 specialists in surgical oncology and cancer genetics was established to discuss the cost-effectiveness of population-based BRCA testing for ovarian cancer. The project was divided into five main areas, each with subtopics assigned among the 14 participants. They were: the existing clinical testing guidelines, the current healthcare infrastructure in the Brazilian public health system, cost-effectiveness analysis, challenges in implementing prophylactic surgeries, and family counseling and risk communication. A comprehensive literature review was conducted, followed by a series of meetings among the article's contributors to reach consensus on unresolved issues. These discussions aimed to build recommendations based on the best available scientific evidence. Using as a basis the current structure already existing within the Brazilian public health service (SUS [Sistema Único de Saude]), and based on the testing of the at-risk population chosen by our experts, we estimated savings. The net savings for a population of 100 000 women would range from BRL 7030.30 (US$1255.41) to BRL 1853.92 (US$331.05). And these costs could have an even greater impact when public service PARP inhibitors are incorporated. The working group of the Brazilian Society of Surgical Oncology understands that large-scale BRCA testing is cost-effective, especially when risk-reducing surgery is implemented. Other measures are important, such as training teams of non-specialists to recognize the population at risk, in addition to creating an entire line of care for patients with ovarian cancer in the SUS.

Humans↗
PubMed1979

HLA antigens in the Arab population of the Gaza Strip.

The HLA antigen system was studied in the Arab population of the Gaza Strip. The lymphocytes of 113 individuals were typed for 13 and 16 antigens at loci A and B, respectively. The distribution of the HLA antigens was found to be similar to that of an average Caucasoid Middle Eastern population. This was more marked when the tested population was compared with Arab populations living in northern Israel or originating from Lebanon, suggesting that they probably all share a common gene pool. The only noteworthy variation in the Gaza population was the high frequency of BW21, previously found only in Eritreans and Turks.

Gene Frequency↗
PubMed1979

Studies of the relationship between Schistosoma and their intermediate hosts. III. The genus Biomphalaria and Schistosoma mansoni from Egypt, Kenya, Sudan, Uganda, West Indies (St. Lucia) and Zaire (two different strains: Katanga and Kinshasa).

The compatibility between strains of Schistosoma mansoni from Egypt, Kenya, Sudan, Uganda, the West Indies, and Zaire (two strains which came from Katanga and from Kinshasa), and various species and strains of Biomphalaria, i.e. Biomphalaria pfeifferi, B. alexandrina, B. glabrata and B. camerunensis was investigated. Data as mortality, rate of infection of the surviving snails, duration of infection, cercarial production per day per positive snail, etc., were observed. The main emphasis was placed on determining the total cercarial production per 100 exposed snails for each snail population. It was possible to infect all the tested populations of B pfeifferi with the various strains of S. mansoni, but the observation as e.g. TCP/100 exposed snails varied greatly according to the population of snail and the strain of S. mansoni. The results for the remaining species of Biomphalaria varied greatly, depending on the combination, e.g. B. alexandrina was only susceptible to the local S. mansoni from Egypt. The highest TCP/100 exposed snails was more than 1 million for the strains of S. mansoni from Egypt, Kenya and the West Indies in B. alexandrina, B. pfeifferi and B. glabrata, respectively. The next group, with a TCP/100 exposed snails on 7--800 000 consists of S. mansoni from Sudan, Uganda and Zaire (Katanga) all in B. pfeifferi. The last tested strain of S. mansoni, Zaire (Kinshasa) yielded a cercarial production on 500 000 per 100 exposed snails in B. pfeifferi and B. camerunensis. The shortest prepatent period, 19 days, was observed for S. mansoni from Kinshasa, Zaire, in B. camerunensis, and the longest prepatent period, 25 days, was found for strains from Egypt and from the West Indies in B. alexandrina and B. glabrata, respectively. In general, a very long duration of infection, lasting up to 200 days, was observed.

Animals↗