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PubMed1994

Non-Hodgkin's lymphoma of the gastrointestinal tract: a population-based analysis of incidence, geographic distribution, clinicopathologic presentation features, and prognosis. Danish Lymphoma Study Group.

PURPOSE: To evaluate incidence, time trends, geographic distribution, clinicopathologic presentation features, and prognostic factors for survival and relapse in gastrointestinal (GI) non-Hodgkin's lymphomas (NHLs). PATIENTS AND METHODS: Over a 9-year period (1983 to 1991), 2,446 new NHL cases were recorded in a Danish population-based NHL registry (Danish Lymphoma Study Group [LYFO]). Of these, 306 (12.5%) were GI NHL (175 gastric, 109 intestinal, and 22 both sites). LYFO registry data were used for incidence rate (IR) assessment, and time-trend and geographic distribution analysis. Relative risk (RR) values for survival and relapse were identified by multivariate analysis. RESULTS: The mean annual, age-standardized IRs for gastric and intestinal NHL were 0.71/10(5) and 0.48/10(5) per year, respectively. Age-specific IRs for both localizations showed an exponential increase as a function of age. Time-trend analysis for the period 1983 to 1991 showed stable IRs for both localizations. Intestinal NHL was more frequent in males (male-to-female ratio, 2.0 v 1.3), and had a higher occurrence of disseminated disease, constitutional symptoms, high-grade histology, and T-cell phenotype (10% v 2%). Gastric NHL had more low-grade cases (38% v 19%), and almost all were of the mucosa-associated lymphoid tissue (MALT) type. The cause-specific 5-year survival rate was 63% for gastric NHL and 49% for intestinal NHL. The Musshoff staging system was an excellent discriminator between truly localized (stage I and II1) and disseminated cases (stage II2 to IV), particularly for gastric NHL, for which no survival difference was found between surgically and conservatively stage localized cases. CONCLUSION: (1) No increase in the incidence of GI NHL was found over a 9-year observation period; (2) nonrandom spatial distribution of new GI NHL cases was observed; (3) factors that significantly increased the risk of death in gastric cases were presence of B symptoms (RR = 3.3), clinical stage is more than II1 (RR = 3.0), age more than 72 years (RR = 2.4), and elevated serum lactate dehydrogenase (s-LDH) level (RR = 2.0); and factors that increased the risk of death in intestinal cases were presence of B symptoms (RR = 3.2), age more than 58 years (RR = 2.8), and clinical stage more than I (RR = 2.1); (4) factors that significantly increased the risk of relapse in gastric cases were male sex and no radiotherapy in primary treatment; and in intestinal cases were T-cell phenotype and no surgery in primary treatment; (5) surgical staging, as opposed to thorough noninvasive staging, did not improve staging accuracy and final outcome in localized gastric NHL.

Adolescent↗

PubMedDate not supplied

Angiostrongylus costaricensis: first record of its occurrence in the State of Espirito Santo, Brazil, and a review of its geographic distribution.

Abdominal angiostrongyliasis is a parasitic disease caused by Angiostrongylus costaricensis, a metastrongylid nematode with wide geographic distribution, occurring from the United States to Argentina. In Brazil, the disease has been reported from the States of Rio Grande do Sul, Santa Catarina, Paraná, São Paulo, Federal District of Brasília and Minas Gerais. We report here a case of abdominal angiostrongyliasis in a 9-year-old girl, from Itatiba, State of Espirito Santo, Brazil, submitted to exploratory laparotomy for acute abdomen. Extensive inflammatory lesions of terminal ileum and cecum, with perforations of the first, were present, and ileocecal resection was performed. The pathological picture was characterized by transmural inflammatory granulomatous reaction, extensive eosinophilic infiltration, eosinophilic vasculitis and the presence of worms within a mesenteric artery branch, with histological features of metastrongylid nematodes. This case report contributes to a better knowledge of the geographic distribution of this parasite in Brazil, suggesting that abdominal angiostrongyliasis may represent a disease of medical importance, more than a rarity of academic interest.

Angiostrongylus↗

PubMed2000

Geographical distribution of publications in Human Reproduction and Fertility and Sterility in the 1990s.

Curious about the geographical distribution of publications in reproductive medicine, we compared the numbers of publications in Human Reproduction (HR) and Fertility and Sterility (F&S). The annual number of publications from the individual countries was obtained by searching the Medline database using the internet provider PubMed. The data were analysed and normalized to population size, gross domestic product (GDP) and total number of Medline publications. The 8511 publications of both journals in the 1990s came from 56 countries. The number of publications per year was increasing in HR and remained constant in F&S. In absolute numbers, the UK produced the most publications in HR (21%) and the USA in F&S (45%) as well as in both journals together (28%). Relatively, Israel was the most productive country per million inhabitants (8.4 +/- 2.1 publications/year), per billion US dollars GDP (0.85 +/- 0.21 publications/year) and per 1000 Medline publications (15 +/- 4 publications/year). Europe was the most productive world region in absolute numbers (54%) and Australia/New Zealand in relative numbers per million inhabitants and per 1000 billion US dollars GDP. Almost 87% of all publications in HR and F&S came from the 18 countries with a GDP per capita of >10 000 US dollars. In conclusion, the geographical distribution of publications in HR and F&S follows the pattern of the distribution of publications in general biomedical research. Most publications come from affluent countries. Although the USA and the UK appear to be the most productive countries in absolute numbers, smaller affluent countries like Israel and Belgium are more productive when the numbers are normalized to population or GDP.

Australia↗

PubMed2001

Geographic distribution of hepatitis B virus (HBV) genotype in patients with chronic HBV infection in Japan.

The geographic distribution of hepatitis B virus (HBV) genotypes in Japan and its clinical relevance are poorly understood. We studied 731 Japanese patients with chronic HBV infection. HBV genotype was determined by the restriction fragment length polymorphism (RFLP) method after polymerase chain reaction (PCR). Of the 720 patients with positive PCR, 12 (1.7%) were HBV genotype A, 88 (12.2%) were genotype B, 610 (84.7%) were genotype C, 3 (0.4%) were genotype D, and 7 (1.0%) were of mixed genotype. Over 94% of patients on the Japanese mainland had genotype C, while 60% of the patients on Okinawa, the most southern islands, and 22.9% in the Tohoku area, the northern part of the mainland, harbored genotype B. Compared with genotype C patients, genotype B patients were older (53.6 to 42.2 years; P <.01), had a lower rate of positive hepatitis B e antigen (HBeAg) (18.4% to 50.6%; P <.01), and a lower level of serum HBV DNA (5.02 to 5.87 log genome equivalents (LGE)/mL; P <.01). The mean age of the genotype B patients with hepatocellular carcinoma was 70.1 +/- 9.2 years, compared with 55.2 +/- 9.7 of genotype C patients (P <.01). These results indicate that genotypes C and B are predominant in Japan, and there are significant differences in geographic distribution and clinical characteristics among the patients with the different genotypes.

Adult↗

PubMed2005

[Geographic distribution of Schistosoma mansoni transmitter snail species in State of São Paulo].

A thorough knowledge of the geographic distribution of Schistosoma mansoni vector snails is indispensable for the control of Schistosoma mansoni schistosomiasis and its epidemiologic surveillance. From the water masses of the State of São Paulo (Brazil) 8,771 lots of snails--total of 108,244 individuals of the genus Biomphalaria--were captured between 1982 and 2002. These specimens are now part of the malacological collection of (Superintendência de Controle de Endemias--São Paulo). According to species: Biomphalaria glabrata (Say, 1818), 225 lots (6%)--8,002 (7.4%); specimens Biomphalaria tenagophila (d'Orbigny, 1835), 3,402 lots (91.7%)--88,068 (81.4%) specimens and Biomphalaria straminea (Dunker, 1848), 85 lots (2.3%)--12,174 (11.2%) specimens. The geographic distribution of B. tenagophila and B. glabrata breeding sites tends to be compact and their occupation of territory is clear-cut. B. tenagophila habitats characteristically show a tendency to cluster around municipalities with high levels of urbanization and organic pollution. The presence of B. straminea is isolated in all hydrographic basins. This situation suggests that the persistence of schistosomiasis endemic areas in the State of São Paulo depends on the chance of host-parasite contacts resulting from the concentration of B. tenagophila and B. glabrata breeding sites.

Animals↗

PubMed1994

Geographical distribution, host associations, and vector roles of ticks (Acari: Ixodidae, Argasidae) in Sweden.

This review covers the geographic distribution and host relationships of the tick species in Sweden. Ixodes uriae White, I. caledonicus Nuttall, I. unicavatus Neumann, I. arboricola Schulze & Schlottke, and I. lividus Koch are ornithophagous species. I. trianguliceps Birula, I. canisuga Johnston, I. hexagonus Leach, and Argas vespertilionis (Latreille) are mammalophagous. I. ricinus (L.) and Haemaphysalis punctata Canestrini & Fanzago feed on both birds and mammals. All these tick species may be considered to be permanently present in Sweden. I. persulcatus Schulze, Hyalomma marginatum Koch, and the brown dog tick, Rhipicephalus sanguineus (Latreille), may be regarded as not indigenous to Sweden although they may be regularly introduced by spring-migrating birds or imported dogs, respectively. The first European record of the American dog tick, Dermacentor variabilis (Say), is reported. There are several records of Hyalomma aegyptium (L.) from imported tortoises in Sweden. Excluding other ticks imported on exotic pets and zoo animals, another 13 tick species are listed that may occur, at least occasionally, in Sweden. Because of its wide geographic distribution, great abundance, and wide host range, I. ricinus is medically the most important arthropod in northern Europe. I. ricinus is common in southern and south-central Sweden and along the coast of northern Sweden and has been recorded from 29 mammal species, 56 bird species, and two species of lizards in Sweden alone. The potential introduction to Sweden of exotic pathogens with infected ticks (e.g., I. persulcatus and H. marginatum on birds or Dermacentor spp. and R. sanguineus on mammals) is evident.

Animals↗

PubMed2001

[Mortality caused by cancer in Andalusia: trends and geographic distribution].

AIMS: To describe the evolution of mortality due to gastric cancer in Andalusia and the current geographic distribution of mortality. DESIGN: Descriptive, population-based study. SETTING: Andalusia (Southern Spain) during the period from 1975 to 1999. PARTICIPANTS: Residents of the region of Andalusia. MEASUREMENTS: Crude rates adjusted for age (interval 35-64 years) of potential years of life lost (1-70 years), and cumulative rates (0-74 years), for mortality due to gastric cancer from 1975 to 1999. Linear regression coefficients were calculated from the model that best fit mortality rates standardized across the study period. Age-adjusted rates were calculated for the five-year period from 1995 to 1999 for primary health care districts. RESULTS: A sustained decrease in mortality (standardized rate per 100000 inhabitants) due to gastric cancer was seen in women (15.9 to 5.8) and men (33.9 to 14.5). The Sierra Norte (Seville province), Huelva and Córdoba districts, together with the Guadix district (Granada province), had the highest age-adjusted rates for the period from 1995 to 1999. Mortality rates were higher in men than in women throughout the period analyzed; the male:female ratio was consistently greater than 2. CONCLUSIONS: Mortality due to gastric cancer decreased notably in Andalusia during the last quarter of the twentieth century, but the current geographic distribution of mortality rates varies across the region. Mortality rates in some primary health care districts were threefold as high as in other districts where mortality was low. Further analytical studies are needed to clarify the possible causes of these marked local differences.

Adult↗

PubMed1998

Geographic distribution and clinical description of leishmaniasis cases in Peru.

Studies were conducted from 1986 through 1993 to further define the geographic distribution and relative importance of different species of Leishmania as a cause of leishmaniasis in Peru. Patients with a clinical diagnosis of cutaneous and/or mucosal or diffuse cutaneous leishmaniasis were enrolled at the Naval Medical Research Institute Detachment (NAMRID) Laboratory in Lima, the Tropical Disease Clinic at San Marcos University Daniel A. Carrión, the Central Military Hospital, and a Ministry of Health hospital in Cusco, Peru. Clinical features, lesion aspirates, and biopsy tissue were obtained from each patient. All specimens were collected and assayed separately, including multiple specimens from some of the same patients for Leishmania parasites by inoculating aliquots of either aspirates or biopsy tissue suspensions onto Senekji's blood agar medium. Stocks of Leishmania isolates were used to prepare promastigotes to produce extracts for identifying the Leishmania species by the cellulose acetate electrophoresis enzyme technique. A total of 351 isolates of Leishmania were obtained from 350 patients who were infected primarily in the low and high jungle of at least 15 different Departments of Peru. Of the 351 isolates, 79% were identified as L. (V.) braziliensis, 7% as L. (V.) guyanensis, 10% as L. (V.) peruviana, 2% as L. (V.) lainsoni, and 1.7% as L. (L.) amazonensis. The clinical form of disease varied depending on the species of Leishmania, with L. (V.) braziliensis being associated most frequently with cutaneous, mucosal ulcers and mixed cutaneous and mucosal disease, and L. (V) peruviana, L. (V.) guyanensis, L. (V.) lainsoni with cutaneous lesions. Leishmania (L.) amazonensis was isolated from six patients, three with cutaneous lesions, one with mucosal lesions, and two with diffuse cutaneous lesions. Among all of the leishmaniasis cases, males were affected more frequently, and cases occurred among patients less than 10 to more than 51 years of age. These data further defined the geographic distribution and the relative frequency of Leishmania species associated with different clinical forms of leishmaniasis in Peru.

Adolescent↗

PubMed1995

Effects of interstate migration on the geographic distribution of stroke mortality in the United States.

BACKGROUND AND PURPOSE: This study examines the effects of lifetime net interstate migration on the geographic distribution of stroke mortality in the United States. METHODS: National Center for Health Statistics and Bureau of the Census data were used to map the geographic distribution of age-adjusted, race-, and race/sex-specific stroke mortality rates by interstate migration status for natives, outmigrants, nonmigrants, inmigrants, and residents in the United States for 1979 to 1981. RESULTS: High age-adjusted stroke mortality rates were significantly clustered in the southeastern United States for both whites and blacks; in addition, for whites, low-rate states were concentrated in some Mountain and northeastern states. Migrant status did not change this large-scale pattern, but individual states showed significant migration effects, which varied in magnitude and direction. Among whites, states that benefited from migration, with markedly lower stroke mortality rates among residents than natives, included Arizona, Colorado, District of Columbia, and Florida, whereas states that suffered from migration included California, Idaho, Montana, North Dakota, Nevada, and Oklahoma. Among blacks, only Colorado showed an apparent large benefit from migration, whereas 21 states suffered from migration. CONCLUSIONS: Although the overall large-scale spatial distribution of resident stroke mortality rates cannot be explained by migration effects, some individual states had rates that were strongly influenced by migration. Patterns of mortality among migrant groups in Sun Belt retirement destination states probably result from differential selection effects for retirement migration in older adults. Patterns of mortality for black migrants to the North are probably influenced by "carryover" effects from their origin states.

Adult↗

PubMed1989

A review of the geographic distribution and epidemiology of leishmaniasis in the New World.

A review of the epidemiologic aspects of the New World leishmaniases, including their known geographic distribution, etiologic agents, zoonotic reservoirs, and insect vectors, based on biological and molecular characterization of Leishmania isolates is presented. Data summarized in this paper on parasite taxonomy and geographic distribution come from our studies of greater than 1,000 New World Leishmania isolates identified by species-specific monoclonal antibodies using an indirect radioimmune binding assay and from scientific literature.

Animals↗

PubMed2003

[New findings on the geographic distribution of the verrucarum group (Diptera: Psychodidae) in Colombia].

The incrimination of sand flies belonging to verrucarum species group in the leishmaniasis transmission underscores the need for a detailed information on the geographical distribution of these species. The current listing adds 34 new records that extend significantly the knowledge of the geographical distribution of the verrucarum group in Colombia. The most important new records pertain to Lutzomyia spinicrassa in the tropical dry forest of the Atlantic coast, Lutzomyia ovallesi in the Orinoco and Amazon River watersheds regions of Colombia, and the sympatric occurrence of Lutzomyia spinicrassa and Lutzomyia quasitownsendi in the eastern chain of the Andes mountains. Additionally, the municipal and altitudinal distributions are compiled for 19 new species recorded for Colombia. The series townsendi of the verrucarum group generally restricted to premontane and lower montane zones based on distribution data on Lutzomyia longiflocosa, L. quasitownsendi, Lutzomyia sauroida, L. spinicrassa, Lutzomyia torvida, Lutzomyia townsendi and Lutzomyia youngi. The series verrucarum is distributed from the tropical lowland to the montane zones, and includes species with wide geographical range (Lutzomyia evansi, Lutzomyia columbiana, L. ovallesi, Lutzomyia nuneztovari, Lutzomyia nevesi), and species of highly endemic distribution (Lutzomyia andina, Lutzomyia disiuncta, Lutzomyia moralesi, Lutzomyia antioquiensis). Members of the series pia (Lutzomyia pia, Lutzomyia limafalcaoae) and the series serrana (Lutzomyia serrana) occur from the tropical lowlands to the lower montane zones. The altitudinal divergences may be intrinsically tied to speciation process, especially as it relates to the climatic and geologic events that have affected the flora and fauna of the Andean region.

Animals↗

PubMed1999

Geographic distribution of vacA allelic types of Helicobacter pylori.

BACKGROUND & AIMS: Distinct allelic types of Helicobacter pylori vacA have been defined. The geographic distribution of vacA alleles and cagA was assessed in this study. METHODS: A total of 735 cultures from patients in 24 countries were analyzed by polymerase chain reaction and reverse hybridization on a line probe assay (LiPA). RESULTS: In 124 (16.9%) of the 735 cultures, multiple vacA genotypes were detected, permitting analysis of 611 strains. In Europe, a distribution gradient of s1 subtypes was observed. In northern and eastern Europe, 89% were subtype s1a. s1a and s1b were equally present in France and Italy, whereas in Spain and Portugal 89% of strains were subtype s1b. s1a and s1b were approximately equally prevalent in North America. In Central and South America, virtually all s1 strains were subtype s1b. Subtype s1c was observed in 77% of the s1 isolates from East Asia. m1 and m2a have equal presence, except on the Iberian peninsula and in Central and South America, where m1 (86.2%) is more prevalent than m2 (13.8%). Subtype m2b was found exclusively among East Asian s1c strains. In all parts of the world, vacA s1/cagA-positive genotypes were associated with peptic ulcer disease (P < 0.001). CONCLUSIONS: These data indicate a geographic distribution of H. pylori genotypes and aid in understanding the relationship of H. pylori with disease.

Alleles↗

PubMedDate not supplied

Geographical distribution of common surnames in England and Wales.

Analysis of the geographical distribution of 84 common surnames indicated that nearly all surnames are not distributed at random, but show distinctive geographical patterning. Factor analysis also revealed that there were similarities between surname distributions. The first two factors highlighted primarily Welsh surnames while the third and fourth factors were generally north of England names, mainly those ending in 'son'.

England↗

PubMed1996

Association between duration of humid season and geographical distribution patterns of different species of chewing lice (Mallophaga:Insecta) infesting domestic chickens in Nigeria.

In a countrywide study of the geographical distribution patterns of chicken lice in Nigeria, 3 species, Menacanthus pallidulus (Neumann 1912), Goniodes dissimilis Denny, 1842, and Menopon gallinae (Linnaeus, 1758), were completely restricted to within areas with a long humid season (6-12 humid mo per yr). In constrast, 4 species, Cuclotogaster occidentalis Tendeiro, 1954, Menacanthus cornutus (Schommer, 1913), Amyrsidea powelli (Bedford, 1920), and Goniodes gigas (Taschenberg, 1879), thrived only in areas where the humid season was of a short duration (< or = 5 mo). The last 3 named species extended also into the fringes of areas with a long humid season (6-8 humid mo) at significantly reduced numbers. They were entirely absent in areas with a particularly protracted humid season (9-12 humid mo). Three other species. Numidilipeurus tropicalis (Peters, 1931), Goniocotes gallinae (DeGeer, 1778), and Lipeurus caponis (Linnaeus, 1758), were just as abundant in areas of a long humid season as they were in areas with a short humid season. It was concluded that there was an association between duration of the humid season and the geographical distribution patterns of certain species of chicken lice in Nigeria. The duration of the humid season might thus provide a means of predicting the potential occurrence of some species of chicken lice in a particular area.

Analysis of Variance↗

PubMed1995

[Study on geographic distribution of smear-positive pulmonary tuberculosis with trend-surface analysis].

The Trend-surface Analysis method was used to study the geographic distribution of smear-positive pulmonary tuberculosis prevalence in China. The prevalence data used in this article was cited from Nation-wide Tuberculosis Surveys in 1979 and 1990. The results showed that smear-positive pulmonary tuberculosis prevalence had obvious characteristics of geographic distribution and the characteristics had been changed within 11 years. In a word, the smear-positive pulmonary tuberculosis prevalence distribution tallies with their quality of tuberculosis control.

China↗

PubMed1997

Geographic Distribution of Endangered Species in the United States

Geographic distribution data for endangered species in the United States were used to locate "hot spots" of threatened biodiversity. The hot spots for different species groups rarely overlap, except where anthropogenic activities reduce natural habitat in centers of endemism. Conserving endangered plant species maximizes the incidental protection of all other species groups. The presence of endangered birds and herptiles, however, provides a more sensitive indication of overall endangered biodiversity within any region. The amount of land that needs to be managed to protect currently endangered and threatened species in the United States is a relatively small proportion of the land mass.

Journal Article↗

PubMed1987

Geographic distribution of Bhanja virus.

A review on the geographic distribution, vectors and hosts of Bhanja virus (Bunyaviridae) is based on reports about: isolations of the virus; antibody surveys. Bhanja virus has been isolated in 15 countries of Asia, Africa and Europe, and antibodies against it have been detected in 15 additional countries. Vector range includes ticks of the family Ixodidae (subfam. Amblyomminae; not subfam. Ixodinae): 13 species of 6 genera (Haemaphysalis, Dermacentor, Hyalomma, Amblyomma, Rhipicephalus and Boophilus) yielded the virus. Bhanja virus has only rarely been isolated from vertebrates (Atelerix, Xerus, Ovis, Bos; possibly bats), though antibodies have been detected frequently in a wide range of mammals (Ruminantia being the major hosts), in several species of birds (Passeriformes, Galliformes) and even reptiles (Ophisaurus apodus). Natural foci of the Bhanja virus infections are of the boskematic type (sensu Rosický), associated closely with pastures of domestic ruminants infested by ticks in the regions of tropical, subtropical and partly temperate climatic zones.

Africa↗

PubMed1992

[Genetic differentiation of the inhabitants of Mongolia. Geographic distribution of mitochondrial DNA RFLPs and mitotypes in the inhabitants of Mongolia and a population assessment of the mutation rate in the mitochondrial genome].

The geographical distribution of the Asian specific deletion--insertion polymorphisms and or the RFLP's in the V noncoding region and the D-loop and of the mitotypes was analysed in Mongolia. The frequencies of the mtDNA markers demonstrated homogeneity of 18 local groups in Mongolia. The geographical distribution of the mitotypes showed the existence of two ancestral maternal lineages in mongols. There was no significant difference in the average FST values between mitochondrial gene flow and the nuclear gene flow of the Mongolian population. The equality of FST values permit to calculate the mutation rate for the human mtDNA--6.10(-9) per nucleotide per year. The data reveals the Mongolian population is in the equilibrium.

DNA, Mitochondrial↗