Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “NEGROES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMedDate not supplied

Lipid composition of cerebral vessels in American Negroes, Caucasians and Nigerian Africans: a comparative study.

The lipid content of cerebral vessels from American Negroes, Caucasians and Nigerian Africans living in urban areas was chemically quantitated. There are significant differences between the total and free cholesterol content of the vessels among the three population groups. The american Negroes have the greatest amount of cerebral vascular cholesterol compared with American Caucasians and Nigerians. This confirms previous morphological observations that the severity and extent of cerebral atherosclerosis are greater in American Negros than in American Caucasians and aftricans. However, there is no significant difference in the phospholipid content of the cerebral vessels except among the female Negro groups. Chemical quantitation of lipids in vessels may be utilized for assessment of degree of atherosclerosis and may prove to be an acceptable and reliable alternative methodology for epidemiological studies.

Adolescent↗
PubMedDate not supplied

[Influence of hypertension on the incidence of end-stage renal disease in negroes and mulattoes with glomerulonephritis].

OBJECTIVE: To assess whether hypertension diagnosed during the first two months of follow-up is associated with the incidence of end-stage renal disease (ESRD) in negroes and mulattoes with glomerulonephritis after taking into account age, gender and the histological diagnosis. METHODS: A retrospective cohort study based on a sample of' 120 negro and mulatto patients with glomerulonephritis, 26 with membranoproliferative glomerulonephritis (MPGN), 58 with focal segmental glomerulosclerosis (FSG) and 36 with other types of glomerulonephritis (OTGN). Hypertension was considered present if antihypertensive treatment was used, in adults (age >18 years) with a mean of the three first systolic blood pressures of 140 mmHg or a mean of the corresponding diastolic blood pressure of 90 mm Hg or greater. For ages equal to or below 18 years the criteria recommended by the "Task Force on Blood Pressure in Children" were used. RESULTS: Hypertension was diagnosed in 48 of the 120 patients (41.6%). The incidence of ESRD was approximately 2.6 times higher in hypertensive patients (relative risk(RR)=2.62; 95 % confidence interval (CI) =1.01-7.03, p=0.031). This association between hypertension and higher risk of ESRD was similar between the group younger than 19 and the group older than 18 years. Even after adjusting for age, gender and histologic type, the incidence of ESRD remained higher (and marginally significant) in the hypertensive than in the normotensive group (adjusted RR=2.15; IC 95%=0.86-5.39, p=0.07). CONCLUSIONS: According to the findings, early detection of hypertension in negroes and mulattoes with glomerulonephritis helps to identify patients with higher risk of ESRD, independently of age, gender and histologic type. Further research is needed to determine to what extent the severity of hypertension and the degree of blood pressure control contribute to the development of ESRD in negroes and mulattoes with glomerulonephritis.

Adult↗
PubMed1978

Physical growth of Negro children in the Durban area.

Physical growth measurements from birth to 145 months in 5,743 urban Negro children in the Durban area have shown that the median weight of the youngest members is similar to or heavier than an international reference standard (Harvard), whereas older children are generally lighter. Length measurements up to 24 months are similar to the standard whereas older children are shorter. Head circumference is greater than international values at all ages measured. The prevalence of malnutrition, assessed by values less than the third Harvard centile for age, reached a peak incidence for height in the pre-school children and for weight in the older male school children. Decreases in height and weight in the Negro child probably reflect the damaging effects of an impoverished socio-economic environment on growth. The development of the young Negro child along reference centiles implies that such standards established in the 'developed world' are appropriate for assessment of adequate growth in South African Negro children of all ages.

Black People↗
PubMed1978

Serum alpha 2 globulin concentrations in South African Negro adults free from coronary heart disease.

In Western populations serum alpha 2 globulin concentration has been reported to be significantly higher in patients with coronary heart disease (CHD) compared with those unaffected. In South Africa, since CHD is extremely rare in Negroes in rural areas, it was judged of value to determine serum alpha 2 globulin concentrations in I. groups of rural elderly Negroes (men and women), and, for comparison, II. two groups of middle-aged to elderly White men, one free from overt CHD, and the other, patients with CHD. Mean values on the Negroes were significantly higher than those on both the White groups. In the latter, the group with CHD had a significantly higher mean value than the non-CHD group. Possible reasons for high values in the Negro groups are an ethnic difference, early malnutrition, greater exposure to infections, and pattern of habitual diet. It is concluded that interpretation of a raised serum alpha 2 globulin concentration in relation to proneness to CHD is influenced by the population concerned.

Age Factors↗
PubMed1964

SENSITIVITY TO HISTOPLASMIN AMONG NEGRO AND WHITE RESIDENTS OF DIFFERENT COMMUNITIES IN THE USA.

The frequency of infection with the fungus Histoplasma, as judged by the results of skin tests with histoplasmin, varies widely from county to county across the USA and even over very short distances within some counties. Differences between various segments of the population, such as between Negroes and whites, living in one particular community are therefore difficult to interpret, as they might represent the effect of differences in ecological rather than in demographic factors within the community. Since the pertinent ecological differences could, however, be expected to balance out if a large number of communities were sampled, results of histoplasmin skin tests among Negro and white Navy recruits from 37 different communities are compared in the present report. The prevalence of reactors to histoplasmin ranges from zero to over 90% in residents of the different geographical areas, indicating wide variations in the ecological conditions affecting the growth and dissemination of the fungus, yet comparisons of results in Negroes and whites indicate that the factors influencing infection and sensitization of man appear to bear equally on both racial groups. Results with tuberculin PPD-S and the Battey PPD antigen in the same groups of recruits are included to supplement the results with histoplasmin.

Black People↗
PubMed1975

The dermatoglyphics of American Negroes.

Digital and palmar dermatoglyphics of 184 male and 224 female normal American Negroes were evaluated for digital patterns, digital ridge counts, palmar patterns, palmar main line terminations, accessory triradii and palmar creases. All subjects were seven year olds examined and found free of chronic or other genetic diseases. The results were presented for the left and right hand separately as well as in terms of bilateral symmetry. The present results were for the most part comparable to those of the African and other American Negro groups reported earlier. The distributions of the various dermatoglyphic features among the Negroes taken as a group were compared to those of the other racial groups and their differences were discussed.

Africa↗
PubMed1986

On the genetic interrelationships of South African Negroes.

This study addresses the comparative genetic interrelationships between South African Negro groups. For this the genetic distances between seven ethnically defined Negro subsamples (total of 998 individuals) based on 24 genetic loci/polymorphisms are calculated by applying standard distance formulae. These computations offer an opportunity to evaluate the different polymorphisms in terms of their effects on the genetic distances. The genetic interrelationships thus computed are illustrated by way of dendrograms and are discussed in terms of their comparative significance. It follows from the findings that the Ndebele, Northern Sotho (Pedi), and Tswana form a closely related subcluster and that the Zulu and Swazi as well as the Venda and Shangana-Tsonga form two additional, more distant, subclusters. These results are discussed and tentatively interpreted against the background of the reported Khoisan admixture of the populations concerned as well as their ethnological history. The data are also compared to those derived from metric and dermatoglyphic studies. It is concluded that whereas there is some agreement between these categories of variation (genetic, metric, and dermatoglyphic) as far as the comparative evaluation of South African Negro groups is concerned, there also are discrepancies. These conclusions need to be explained in terms of evolutionary mechanisms (such as historic origins, hybridization, natural selection, and genetic drift) in order to obtain a more consistent and comprehensive comparative picture of the physical anthropology of southern African populations.

Black People↗
PubMed2003

Mercury biomagnification in a tropical black water, Rio Negro, Brazil.

The population living along the riverbanks of the Amazon basin depends heavily on fish for nutritional support. Mono-methyl-mercury (MMHg) concentrates in fish, which can contaminate humans, the risk depending not only on fish MMHg concentration but also on the amount of fish consumed. We sampled nine locations of the Rio Negro basin, differing in water pH, Hg concentrations, and dissolved organic carbon (DOC), and determined total Hg from 951 fish samples of species representative of the food web: herbivorous, detritivorous, omnivorous, and piscivorous. Mercury concentrations varied widely in all species but showed a trend that depended on fish feeding strategies. The highest mean concentration was found in the piscivorous species (688.90 ng/g(-1)), followed by omnivorous (190.30 ng/g(-1)), detritivorous (136.04 ng/g(-1)), and herbivorous (70.39 ng/g(-1)). Fish Hg concentrations exceeding current safe limits (500 ng/g(-1)) for human consumption were found mainly in the piscivorous species (60%). Significant positive correlation between fish weight and Hg concentration was seen for the piscivorous Serrasalmus spp. (n = 326; r = 0.3977; p < 0.0001), Cichla spp. (n = 125; r = 0.4600; p < 0.0001), and Pimelodus spp. (n = 12; r = 0.8299; p = 0.0008), known locally as Piranha, Tucunaré, and Mandi, respectively. However, a negative correlation was seen for non-piscivorous Potamorhina latior (n = 30; r -0.3763; p = 0.0404) and Leporinus spp. (n = 44; r = -3987; p = 0.0073), known as Branquinha (detritivorous) and Aracu (omnivorous). Fish-Hg concentrations in the acidic waters (pH range, 4.09-6.31) of the Rio Negro habitat, with its wide gradient of Hg concentrations (3.4-11.9 microg/L(-1)) and DOC (1.85-15.3 mg/L(-1))--but no history of gold mining activity-are comparable to other Amazonian rivers. Opportunity fish catches in the Rio Negro habitat show high muscle-Hg derived from natural sources, but no systematic association with site-dependent geochemistry.

Animals↗
PubMed2003

Heavy metals in the vicinity of a chlor-alkali factory in the Upper Negro River ecosystem, Northern Patagonia, Argentina.

A study on heavy metal contents was performed in sediments and biota of the Upper Negro River (Alto Valle) aquatic system, Northern Patagonia, Argentina. The irrigation system of the Neuquén and Negro Rivers runs alongside these rivers for 150 km, supporting intensive agricultural and economical activities, mainly related to fruit production. A mercury cell chlor-alkali factory operated between 1951 and 1995. Close attention was given to the surroundings of the plant, located next to the Main Irrigation Channel, and to the PII drainage channel which received the plant's effluents between 1951 and 1979. From 1979 until its closure, the effluents were pumped above a ravine to a series of evaporation and decantation pools. Mercury and other heavy metals and metalloids (Ag, As, Ba, Co, Cr, Cs, Ni, Sb, Se, U and Zn) contents were measured for bottom sediments of the river and irrigation and drainage channels, for two widespread species of macrophytes (Potamogeton pectinatus and Myriophyllum brasiliensi), and for liver and muscle of native fish Odontesthes microlepidotus. River bed sediments show no evidence of heavy metal accumulation, however, biota might indicate that contaminants are entering the rivers. Mercury was the only element accumulated in the Main Irrigation channel sediments, the highest contents occurring in the surroundings of the nowadays shut-down chlor-alkali plant, returning to background values approximately 40 km downstream the plant. At the plant site, sediments from the center of the channel showed a decrease in Hg content in the upper 10 cm layer, ranging from 0.8 to 3.4 microg g(-1), and from 2.8 to 13.7 microg g(-1) in the next 10 cm lower layer. Conversely, the PII drainage channel sediments showed accumulation of Hg (2-4 microg g(-1)), distributed uniformly at different depths and along the channel, until its mouth at Negro river. Mercury contents of macrophytes downstream the chlor-alkali plant are higher than the baseline for the area, and macrophytes and fish liver from the PII drainage channel present the highest content in this element. The drainage channel system showed different degrees of impact, those channels flowing through densely populated areas being the most affected.

Animals↗
PubMed1975

Intestinal polyps in American negroes and Nigerian africans.

Forty Africans from Nigeria and 89 American negroes with colorectal polyps were analysed by age, sex and type of polyp. The Nigerians were much the younger group (mostly under 20 years of age, whereas most of the American negroes were over 50) and far fewer of their polyps were truly neoplastic (7.5% compared with 87% of the Americans). These differences may be partly due to the American negro population being older than the Nigerian, and partly to environmental factors like those previously postulated to account for the difference in colon cancer incidence between these populations.

Adolescent↗
PubMed1988

The pattern of leucocyte response to surgical trauma in the African Negro.

The leucocyte response to surgical trauma in the Nigerian Negro is investigated. The surgical operations were graded, according to the degree of anticipated tissue trauma, into minor, intermediate and major, in 66 patients (27 males and 39 females) who had elective surgical operations with no sign of infection. The peripheral blood total and differential leucocyte counts were determined pre-operatively and at 2 h, 24 h, and 7 days postoperatively. A highly significant increase (P less than 0.001) in the total leucocyte, polymorphonuclear leucocyte (PMN) and stab cell counts occurred 2 h and 24 h after major surgery. These changes persisted for 7 days after major surgery except for the stab cell count which was by then no longer significantly raised. Similarly, highly significant increases occurred in the total and PMN counts 2 h and 24 h after intermediate surgery. The increases were not significant by the 7th postoperative day. There was a decrease in the lymphocyte counts after major surgery which was not significant at 2 h but was just significant (P less than 0.05) 24 h postoperatively. There was a return to the pre-operative level by the 7th postoperative day. There were no significant changes in the leucocyte counts after minor surgery or in the monocyte, eosinophil and basophil counts after intermediate or major surgery. Despite lower pre-operative total leucocyte (WBC) and PMN counts found in this study, the total leucocyte and PMN response to surgical trauma in the Nigerian Negro is similar to previous observations made in the Caucasian. The response of lymphocytes in the Nigerian Negro, however, differs from that reported in the Caucasian and demands further study.

Adolescent↗
PubMed1975

S--s--U-- phenotype in South African Negroes.

A Negro woman of the Xhosa tribe of Port Elizabeth in the Eastern Cape was found to be S--s--U--with anti-U in her serum. She had two S--s--U-- children, and her husband, father and other children all had single doses of S or s antigen. Three furhter S--s--U-- Negroes were found in a random sample of 1,000 Negro antenatal patients at Port Elizabeth.

Adult↗
PubMed1973

Beta-thalassemia in the American Negro.

In Italian patients with high hemoglobin A(2) beta-thalassemia trait, the synthesis of beta-chains of adult hemoglobin in the peripheral blood is approximately one-half that of alpha-chains. In this study the relative rates of beta- and alpha-chain synthesis were determined in 26 Negro heterozygotes and five homozygotes for beta-thalassemia in six families. The beta/alpha ratio of globin synthesis was decreased in only 15 heterozygotes, whereas in the other 11, beta/alpha globin synthesis was in the normal range or was slightly increased. These unusual findings did not appear to be due to the presence of alpha-thalassemia or a hyperactive "normal" beta-allele. This study demonstrates that the beta/alpha ratio of globin synthesis in the peripheral blood is normal in some patients with beta-thalassemia trait. In five Negro homozygotes with relatively mild clinical disease the beta/alpha ratios were similar to those of Caucasians with Cooley's anemia. Further studies are needed to explore the relationship between normal synthesis ratios in many Negro heterozygotes and milder clinical disease in homozygotes in the same families.

Adolescent↗
PubMed1977

The morphometry and pathological anatomy of the lumbar spine in South African negroes and caucasoids with specific reference to spinal stenosis.

Direct measurements were made on 2,166 lumbar vertebrae of 433 adult negro and caucasoid skeletons. On statistical analysis, forty-five vertebrae in twenty-seven skeletons were found to be stenotic, the mid-sagittal diameter being the significantly reduced dimension. Whereas spinal stenosis syndromes are rare in South African negroes, the lumbar canal is marginally narrower in the negro. There is a uniformity of configuration and capacity of the lumbar spinal canal, which transcends race and sex. By a new method of determining the dorsal limit of the lumbar canal on lateral plain radiography, the overall average lower limit of normal of the mid-sagittal diameter is established at 15 millimetres, and of the transverse diameter 20 millimetres. Bony degenerative changes are more likely to cause neurological compression in the nerve root tunnel than in the spinal canal. The role of skeletal narrowing of the spinal canal as an exclusive cause of the spinal stenosis syndrome may have been exaggerated.

Adolescent↗
PubMed2006

Morphobiological aspects of Rhodnius brethesi Matta, 1919 (Hemiptera:Reduviidae) from the Upper and Middle Negro River, Amazon region of Brazil: I - scanning electron microscopy.

The occurrence of autochthonous cases of Chagas disease in the Amazon region of Brazil over recent decades has motivated an intensification of studies in this area. Different species of triatomines have been identified, and ten of these have be proven to be carriers of the parasite Trypanosoma cruzi or " cruzi-like " parasites. Studies conducted in the municipalities of Santa Isabel do Rio Negro and Barcelos, located on the Upper and Middle of the Negro River, microregion of Negro River, state of Amazonas have confirmed not only that Rhodnius brethesi is present in the palm tree Leopoldinia piassaba, but also that this insect was recognized by palm fiber collectors. A morphological study of eyes, inter-ocular and inter-ocellar regions, antennae, buccula, labrum, rostrum, stridulatory sulcus and feet, including the apex of the tibia, spongy fossette and ctenidium was conducted by scanning electron microscopy. The buccula and the stridulatory sulcus presented notable differences in specimens of different genera and also of different species. These data make it possible to suggest that the details presented in these structures can be included as diagnostic characteristics to be used in new dichotomous keys, thereby contributing towards studies of taxonomy and systematics and furnishing backing for comparative analysis of specimens collected from different localities.

Animals↗
PubMed2001

Diel variation of larval fish abundance in the Amazon and Rio Negro.

Many streams and large rivers present higher ichthyoplankton densities at night. However, in some rivers this does not occur and larvae are equally abundant during the day. Larval drift diel variation is an important information for planning sampling programs for evaluating larval distribution and production. The aim of this study was to test whether the abundance of larval fish was different at either period. We tested it by comparing day and night densities of characiform, clupeiform and siluriform larvae during five years in the Amazon and one year in Rio Negro. We found that larvae of three species of characiform and larvae of siluriform were equally abundant during day and night in the Amazon. Conversely, the catch of Pellona spp. larvae was significantly higher during the day. In Rio Negro, however, larval abundance was higher during the night. These results imply that day samplings estimate adequately the abundance of these characiform and siluriform larvae in the Amazon, but not Pellona larvae. Evaluations of larved densities of Rio Negro will have to consider night sampling.

Animals↗
PubMed1977

Rheumatic disorders in the South African Negro. Part IV. Gout and hyperuricaemia.

The prevalence of gout and the frequency distribution of serum uric acid (SUA) concentrations have been studied in four South African populations. Approximately 450 respondents over the age of 15 years were investigated in each of the following: a tribal Xhosa community in Transkei; a rural Tswana community in the northwestern Transvaal; an urban Negro population in Johannesburg; and a Caucasian community in the same city. No case of gout was encountered in any of the Negro groups, while the prevalence among the urban Caucasians was 13/1 000 men and 3/1 000 women. The mean SUA concentrations showed two consistent trends: (i) the levels rose with age in all four populations and in both sexes; (ii) they were generally higher in men than in women throughout the age range. There was, moreover, an increase in SUA concentrations with increasing sophistication of lifestyle (P less than 0,01), the lowest levels occurring in the tribal Africans, and the highest in the urban communities. This latter finding could not be explained on a genetic basis, nor were there significant differences in physical configuration and nutritional status among the three Negro groups. It is suggested that hyperuricaemia, and possibly the clinical manifestations of gout, have a polygenic aetiology in which acculturation plays an important contributory role.

Adolescent↗