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PubMed1978

Chronic gastric ulcer and stress. A comparison of an ulcer population with a control population regarding stressful events over a lifetime.

Stress was measured by the frequency of 31 major life events with consequent change and distress scores in 50 patients with chronic gastric ulcer and 50 control subjects, matched for age, sex and place of residence. The gastric ulcer population did not differ from the control population regarding the number of events experienced and the associated change and distress scores. However, when analysed according to social grade, the ulcer patients in the lower status suburbs experienced more events and more change than their controls, but the stress scores were similar. In the higher status suburbs, no difference was present between the patients and controls. Change and distress scores rose progressively with age, but there was no significant difference in the number of events experienced between the three age groups. Both men patients and their controls experienced significantly more events and higher change scores than women patients and their controls.

Adult↗
PubMedDate not supplied

Atypical squamous cells of undetermined significance in the pediatric population. Implications for management and comparison with the adult population.

OBJECTIVE: To determine the significance of an atypical squamous cells of undetermined significance (ASCUS) diagnosis in patients 18 years or younger. STUDY DESIGN: From June 1994 to June 1995, 630 cervicovaginal smears were performed on patients 18 years or younger (mean age 16.4, range 14-18) at University Hospitals of Cleveland. Of these patients, 69 (10.9%) were diagnosed with ASCUS or ASCUS with a qualifying statement. Follow-up cervicovaginal smears, biopsies and charts were reviewed for a 12-18-month period following the initial diagnosis of ASCUS. RESULTS: The study population was sexually active: 63% were gravid, 21% were multigravid, 68% had a history of sexually transmitted diseases (STDs), and 32% had multiple STDs. Follow-up cervicovaginal smears or biopsies were obtained on 46 patients (32 cervicovaginal smears and 14 biopsies/endocervical curettage cases). Mild to moderate dysplasia was identified in 21.6% of patients (10.8% on cervicovaginal smears and 10.8% on biopsies), and a repeat diagnosis of ASCUS was given in 37%. In patients with a repeat diagnosis of ASCUS, a follow-up cervicovaginal smear or biopsy revealed dysplasia in an additional 13%. The overall rate of dysplasia was 34.7%. CONCLUSION: Regardless of age, the diagnosis of ASCUS in a sexually active patient population has significant implications. Furthermore, we recommend that these patients be managed the same way as high-risk adult patients.

Adolescent↗
PubMedDate not supplied

Mitral valve prolapse and cerebral ischemic events. A comparison between a neurology population with stroke and a cardiology population with mitral valve prolapse observed for five years.

Two populations of patients with mitral valve prolapse were analyzed to identify factors predisposing to the development of cerebral emboli. Of 760 patients followed for up to five years by our cardiologists with echocardiographically demonstrated mitral valve prolapse (MVP), only one, aged 82 years, has had a stroke. In contrast, of 43 patients admitted to our neurology service with a cerebral embolus and no evidence of carotid or other cardiac lesion and in whom echocardiography was performed, MVP was present in 9. No contributing etiologic mechanisms were uncovered to account for the disparity between the cardiology and neurology populations. However, with the apparent increased incidence of MVP in young patients with cerebral ischemia, both groups require longitudinal follow-up to understand better the factors that predispose a small percentage of patients with mitral valve prolapse to the development of cerebral ischemia.

Adult↗
PubMed2006

Public awareness of risk factors for cancer among the Japanese general population: a population-based survey.

BACKGROUND: The present study aimed to provide information on awareness of the attributable fraction of cancer causes among the Japanese general population. METHODS: A nationwide representative sample of 2,000 Japanese aged 20 or older was asked about their perception and level of concern about various environmental and genetic risk factors in relation to cancer prevention, as a part of an Omnibus Survey. Interviews were conducted with 1,355 subjects (609 men and 746 women). RESULTS: Among 12 risk factor candidates, the attributable fraction of cancer-causing viral and bacterial infection was considered highest (51%), followed by that of tobacco smoking (43%), stress (39%), and endocrine-disrupting chemicals (37%). On the other hand, the attributable fractions of cancer by charred fish and meat (21%) and alcohol drinking (22%) were considered low compared with other risk factor candidates. For most risk factors, attributable fraction responses were higher in women than in men. As a whole, the subjects tended to respond with higher values than those estimated by epidemiologic evidence in the West. The attributable fraction of cancer speculated to be genetically determined was 32%, while 36% of cancer was considered preventable by improving lifestyle. CONCLUSION: Our results suggest that awareness of the attributable fraction of cancer causes in the Japanese general population tends to be dominated by cancer-causing infection, occupational exposure, air pollution and food additives rather than major lifestyle factors such as diet.

Adult↗
PubMed1997

Population-wide evaluation of disease manifestation in relation to molecular genotype in steroid 21-hydroxylase (CYP21) deficiency: good correlation in a well defined population.

We report a population-wide analysis of all patients with 21-hydroxylase deficiency (21-OHD) found in Finland, a country with a genetically well defined population, in which the effects of other genetic and environmental factors on the phenotype can be expected to be low. In total, 120 patients were identified, and their clinical status was evaluated. Blood samples for CYP21 genotype determination could be obtained from 78 (65%) patients, and their phenotypes were compared with their genotypes. In general, the severity of gene defects correlated well with clinical expression. All patients carrying mutations with the most drastic effects on enzymatic activity had the salt-wasting form of 21-OHD. The I2 splice mutation, which in some reports has been connected with clinical variation, was constantly associated with severe mineralocorticoid deficiency. However, patients with I172N as the determining mutation expressed a wide spectrum of phenotypes; the variation could not be attributed to additional mutations. Although genetically affected males with the nonclassical form had not been clinically diagnosed, our study suggests that nonclassical 21-OHD is substantially more rare in Finland than elsewhere, as indicated by both clinical evaluation and mutational screening.

Adrenal Hyperplasia, Congenital↗
PubMed2006

Impact of PCB and p,p'-DDE contaminants on human sperm Y:X chromosome ratio: studies in three European populations and the Inuit population in Greenland.

OBJECTIVE: Recent studies indicate that persistent organohalogen pollutants (POPs) may contribute to sex ratio changes in offspring of exposed populations. Our aim in the present study was to investigate whether exposure to 2,2 ,4,4 ,5,5 -hexachlorobiphenyl (PCB-153) and dichlorodiphenyldichloroethene (p,p -DDE) affects sperm Y:X chromosome distribution. SUBJECTS AND METHODS: We obtained semen and blood for analysis of PCB-153 and p,p -DDE levels from 547 men from Sweden, Greenland, Poland (Warsaw), and Ukraine (Kharkiv), with regionally different levels of POP exposure. The proportion of Y- and X-chromosome-bearing sperm in the semen samples was determined by two-color fluorescence in situ hybridization analysis. RESULTS: Swedish and Greenlandic men had on average significantly higher proportions of Y sperm (in both cohorts, 51.2%) and correspondingly higher lipid-adjusted concentrations of PCB-153 (260 ng/g and 350 ng/g, respectively) compared with men from Warsaw (50.3% and 22 ng/g) and Kharkiv (50.7% and 54 ng/g). In the Swedish cohort, log-transformed PCB-153 and log-transformed p,p -DDE variables were significantly positively associated with Y-chromosome fractions (p-values 0.04 and <0.001, respectively). On the contrary, in the Polish cohort PCB-153 correlated negatively with the proportion of Y-bearing fraction of spermatozoa (p=0.008). CONCLUSIONS: The present study indicates that POP exposure might be involved in changing the proportion of ejaculated Y-bearing spermatozoa in human populations. Intercountry differences, with different exposure situations and doses, may contribute to varying Y:X chromosome ratios.

Chromosomes, Human, X↗
PubMed1998

Urinary nickel excretion in populations living in the proximity of two russian nickel refineries: a Norwegian-Russian population-based study.

The Russian nickel refineries located in the cities of Nikel and Zapolyarny close to the Norwegian border are responsible for extensive sulfur dioxide and nickel pollution, as well as severe ecological damage in both countries. The aim of our study was to investigate human nickel exposure in the populations living on both sides of the Norwegian-Russian border. The design was a cross-sectional population-based study of adults aged 18-69 years residing in Sor-Varanger municipality, Norway, and Nikel and Zapolyarny, Russia, during 1994 and 1995. Individual exposure to nickel was assessed by measurements of nickel in urine using electrothermal atomic absorption spectrometry. For controls, urine was collected from adults in the Russian cities of Apatity and Umba (Kola Peninsula) and the Norwegian city of Tromso, all of which are locations without nearby point sources of nickel. Altogether 2,233 urine specimens were analysed for nickel. People living in Nikel had the highest concentrations (median 3.4 microg/l), followed by Umba (median 2.7 microg/l), Zapolyarny (median 2.0 microg/l), Apatity (median 1.9 microg/l), Tromso (median 1.2 microg/l), and Sor-Varanger (median 0.6 microg/l). Regardless of geographical location, the Russian study groups all had a higher urinary-nickel average than those in Norway (p<0.001). With the exception of Nikel, neither the Russian nor the Norwegian urinary-nickel levels were associated with residence location near a Russian nickel refinery. We concluded that industrial nickel pollution alone could not explain the observed discrepancy between Norway and Russia; we also discuss other possible nickel exposure sources that may account for the high urinary levels found in Russia.

Adolescent↗
PubMed1989

[Analysis of the health and living conditions of the urban population of Botucatu, SP (Brazil). II. Knowledge and opinion of the population on symptoms of diseases].

It was verified the extent of the information of the urban population of Botucatu, SP (Brazil) on health questions. Knowledge and opinions about frequency and severity of thirteen symptoms and signs of disease were researched in 1005 families sampled. The answers were analyzed according to age, sex, level of education and socio-economic level. They showed a tendency compatible with scientific medical knowledge. In the comparison of the sexes, by age, (young adult) women gave more value to the frequency and severity of most of the symptoms than men. The high scores observed for severity showed a tendency to decrease with the increasing level of education for all the symptoms. There were variations among the symptoms in the appreciation of frequency according to the socio-economic level, with a tendency to a decrease in the high scores related to severity, according to the increase in socio-economic level. The degree of information observed in the population contradicts the prejudice, still existing in the medical area, about laymen's lack of knowledge. The hypothesis that the sample studied had access to several sources of information, among them the extensive local network of medical services, is put forward.

Adolescent↗
PubMed2000

The role of population pharmacokinetics in drug development in light of the Food and Drug Administration's 'Guidance for Industry: population pharmacokinetics'.

Population pharmacokinetics (PPK) has evolved from a discipline primarily applied to therapeutic drug monitoring to one that plays a significant role in clinical pharmacology in general and drug development in particular. In February 1999 the US Food and Drug Administration issued a 'Guidance for Industry: Population Pharmacokinetics' that sets out the mechanisms and philosophy of PPK and outlines its role in drug development. The application of PPK to the drug development process plays an important role in the efficient development of safe and effective drugs. PPK knowledge is essential for mapping the response surface, explaining subgroup differences, developing and evaluating competing dose administration strategies, and as an aid in designing future studies. The mapping of the response surface is done to maximise the benefit-risk ratio, so that the impact of the input profile and dose magnitude on beneficial and harmful pharmacological effects can be understood and applied to individual patients. PPK combined with simulation methods provides a tool for estimating the expected range of concentrations from competing dose administration strategies. Once extracted, this knowledge can be applied to labelling or used to assess various future study designs. PPK should be implemented across all phases of drug development. For preclinical studies, PPK can be applied to allometric scaling and toxicokinetic analyses, and is useful for determining 'first time in man' doses and explaining toxicological results. Phase I studies provide initial understanding of the structural model and the effect of possible covariates, and may later be used to evaluate PPK differences between patients and healthy individuals. Phase II studies provide the greatest opportunity to map the response surface. With these PPK models it is possible to gain an improved understanding of the role of the dose on the response surface and of the range of expected responses. In phase III and IV studies, PPK is implemented to further refine the PPK model and to explain unexpected responses. Planning for the implementation of PPK across all phases of drug development is necessary, as well as planning for individual PPK studies. Planning should include: defining important questions, identifying covariates and drug-drug interactions that need to be investigated, and identifying the applications and intended use of the model(s). The plan for each project must have a strategy for data management, data collection, data quality assurance, staff training for data collection, data analysis and model validation.

Animals↗
PubMed1999

Do we know the real need for hearing rehabilitation at the population level? Hearing impairments in the 5- to 75-year-old cross-sectional Finnish population.

The cross-sectional population sample studied here was randomly selected from the population register of northern Finland. The subjects comprised 10 different age groups between 2 and 75 years of age. Pure tone averages over the frequencies of both 0.5, 1 and 2 kHz and 0.5, 1, 2 and 4 kHz - i.e. better ear hearing levels (BEHL) of BEHL0.5-2kH and BEHL0.5-4kHz - were calculated. The prevalence of various grades of hearing impairment was investigated among the 3518 people who participated in audiometric measurements. Two different classifications were used to grade the hearing impairment. According to the World Health Organization (WHO) classification (1991), 94.3% of the subjects had normal hearing, whereas 3.8% had mild hearing impairment, 1.3% had moderate impairment, 0.4% severe impairment and 0.1% profound impairment. When the more recent EU definition (1996) was used, 85.3% of the subjects had normal hearing. Mild impairment was found in 11.5% of the subjects, moderate impairment in 2.8%, severe impairment in 0.3%, and profound in 0.1%. The difference between the two definitions mentioned above (resulting in different prevalence figures of hearing impairments) is clear. The WHO classification reveals the need for rehabilitation and can thus be used as a basis of resource allocation, whereas the EU proposal reveals even the mildest hearing impairments and hence better illustrates the real prevalence of impairment. The need for the current and future audiological services may be estimated from the prevalence rates of hearing impairments. The proportion of the Finnish elderly - the people most frequently using health services - is expected to increase from today's 15% to 23% within the next 20 years. The same phenomenon is to be expected in other Western societies.

Adolescent↗
PubMed1999

[Distribution of blood lipids in a representative sample of the adult population of Catalonia. Research Group on Assessment of the Nutritional Status of the Catalonian Population: Biochemical Assessment].

BACKGROUND: The leading cause of mortality in Spain are cardiovascular diseases. Their prevention largely depends on the control of hypercholesterolemia. The aim of this study is to describe the serum concentration of total cholesterol (TC), HDL-cholesterol (HDLc), LDL-cholesterol (LDLc) and triglycerides in the population of Catalonia (Spain). SUBJECTS AND METHODS: We obtained a representative sample of the catalan population 18-75 years-old in 1993. The concentrations of HDLc was analyzed after precipitation, the concentration of TC and triglycerides was obtained by enzimatic methods, and the concentration of LDLc was calculated using the Friedewald formula. RESULTS: We obtained a sample of 487 women and 393 men (participation rate: 38%). The mean concentrations of TC, LDLc, HDLc and triglycerides was, respectively, of 203.9 mg/dl (SD = 39.7 mg/dl) (5.24 mmol/l, SD = 1.02 mmol/l), 127.5 mg/dl (SD = 35.9 mg/dl) (3.28 mmol/l, SD = 0.92 mmol/l), 55.8 mg/dl (SD = 14.0 mg/dl) (1.45 mmol/l, SD = 0.36 mmol/l) and 103.9 mg/dl (SD = 75.4 mg/dl) (1.15 mmol/l, SD = 0.84 mmol/l). Nineteen percent of the sample had a concentration of TC > 240 mg/dl (6.42 mmol/l), 3.0% a concentration of HDLc < 35 mg/dl (0.91 mmol/l), 17.2% a concentration of LDL > 160 mg/dl (4.11 mmol/l) and 7.4% a concentration of triglycerides > 7.4 mg/dl (2.22 mmol/l). The concentrations of LDLc and triglycerides and the atherogenic index (TC/HDLc) were higher in men than in women and they increased with age. CONCLUSIONS: The cholesterol levels could be considered lower in Catalonia, Spain, than in other developed countries, and there is a tendency to decrease accordingly to the decrease in the cardiovascular mortality rates. However, the lipid profile in men older than 35 years and in women older than 50 years is still a cause of concern.

Adolescent↗
PubMed1999

Variant genotypes of the low-affinity Fcgamma receptors in two control populations and a review of low-affinity Fcgamma receptor polymorphisms in control and disease populations.

Fcgamma-receptors (FcgammaR) provide a critical link between humoral and cellular immunity. The genes of the low-affinity receptors for IgG and their isoforms, namely, FcgammaRIIa, FcgammaRIIb, FcgammaRIIIa, FcgammaRIIIb, and SH-FcgammaRIIIb, are located in close proximity on chromosome 1q22. Variant alleles may differ in biologic activity and a number of studies have reported the frequencies of variant FcgammaR alleles in both disease and control populations. No large study has evaluated the possibility of a nonrandom distribution of variant genotypes. We analyzed 395 normal individuals (172 African Americans [AA] and 223 Caucasians [CA]) at the following loci: FcgammaRIIa, FcgammaRIIIa, and FcgammaRIIIb, including the SH-FcgammaRIIIb. The genotypic distributions of FcgammaRIIa, FcgammaRIIIa, and FcgammaRIIIb conform to the Hardy-Weinberg law in each group. There was no strong evidence that combinations of 2-locus genotypes of the 3 loci deviated from random distributions in these healthy control populations. The distribution of SH-FcgammaRIIIb is underrepresented in CA compared with AA (P < .0001) controls. A previously reported variant FcgammaRIIb was not detected in 70 normal individuals, indicating that this allele, if it exists, is very rare (<1%). In conclusion, we present data that should serve as the foundation for the interpretation of association studies involving multiple variant alleles of the low-affinity FcgammaR.

Alleles↗
PubMed1999

Apolipoprotein B, apolipoprotein E, and angiotensin-converting enzyme polymorphisms in 2 Italian populations at different risk for coronary artery disease and comparison of allele frequencies among European populations.

Polymorphisms at the apolipoprotein B (APOB XbaI, EcoRI, insertion-deletion), apolipoprotein E (APOE), and angiotensin-converting enzyme (ACE) loci are thought to be involved in susceptibility to coronary artery disease (CAD) and myocardial infarction. The aim of this study was to determine whether the allele distribution of the APOB, APOE, and ACE polymorphisms is different in 2 Italian regions with higher (northern Italy) and lower (Sardinia) CAD occurrence. The frequencies of the APOB and APOE alleles that are considered CAD risk factors were higher in northern Italy (APOB X- = 0.655; APOB R- = 0.198; APOB insertion = 0.757; APOE*4 = 0.110) than in Sardinia (APOB X- = 0.568; APOB R- = 0.159; APOB insertion = 0.680; APOE*4 = 0.052), although only APOE allele frequencies differed significantly (p = 0.001). ACE deletion allele frequencies in the 2 geographic areas showed an opposite pattern (northern Italy = 0.658; Sardinia = 0.721). Furthermore, we investigated the impact of APOB and APOE polymorphisms on interindividual variation in total cholesterol level in the 2 Italian samples, which differ in dietary habits. Only APOE phenotypes showed different mean levels of total cholesterol; the association was significant only in northern Italy (p = 0.04), where continental dietary habits and higher mean cholesterol levels prevail. These results support the suggestion that the cholesterol increasing effect of APOE*4 is environmentally mediated. Analysis of allele distributions among European populations, with remarkable differences in CAD prevalence, revealed a constant positive relationship between APOE*4 allele frequency and CAD incidence. The highest frequencies of APOB X- and R- were observed in Finland, where the incidence of CAD is high, and there is a partial agreement between APOB R- frequency and CAD occurrence across Europe, while APOB insertion and ACE deletion alleles are evenly distributed among European populations.

Alleles↗
PubMed2001

Cross-fertility in two tropical tree species: evidence of inbreeding depression within populations and genetic divergence among populations.

Knowing the spatial patterns of cross-fertility in natural plant populations yields key insight into biparental inbreeding depression, isolation by distance, and, ultimately, speciation. Three adults each of two tropical tree species (Syzygium rubicundum and Shorea cordifolia) were each crossed with five conspecific pollen donors ranging from self to trees occurring in separate forest reserves (12 and 35 km distance for S. rubicundum and Sh. cordifolia, respectively). Cross-fertility was estimated as fruit set, seed germination, and seedling survivorship and height at 1 yr. Means of most cross-fertility measures increased steadily with outcrossing distance, peaking at 1-2 km for S. rubicundum and 1-10 km for Sh. cordifolia, and then declining at the between-forest crosses. However, seed germination and seedling height for Sh. cordifolia suggested hybrid vigor in between-forest crosses. The mean fitness cost of nearest-neighbor mating relative to crossing with more distant neighbors was 45% for S. rubicundum and 0% for Sh. cordifolia. The mean fitness cost of between-forest crosses was 52% and 70% for the two species. Crossing effects on fitness diminished between the stages of fruit set and 1-yr-old seedlings. Results indicate a strong potential for inbreeding depression within forest tree populations and partial reproductive isolation among forests in Sri Lanka's wet zone.

Journal Article↗
PubMed1976

[A medico-genetic study of the population of Western Pamir. IV, Several hereditary neuropsychiatric diseases among the population of the Bartang canyon].

On the basis of clinico-genealogical investigation of the population of some small villages in the ravine Bartang--the isolate in high-montane region--the following indices of frequency of some psychiatric disorders were determined: olygophrenia--3,96; epilepsy--5,09; schizophrenia--6,78 for a 1000 of population. These indices do not differ significantly from those for other regions of the USSR. The favourable evolution of epilepsy and schizophrenia and the absence of genetic froms of olygophrenia were marked.

Consanguinity↗
PubMed1992

Exposure to hepatitis B virus in the general population of Hisayama, Japan: significance of isolated antibody to hepatitis B surface antigen in general population.

Cross-sectional survey on the prevalence of hepatitis B serological markers was performed in 2,411 residents who accounted for 74.4% of the population aged 40 and over and living in Hisayama Town, Japan, in 1983. Overall prevalences were 40.7% for both anti-HBs and anti-HBc, 6.1% for isolated anti-HBs and 5.4% for isolated anti-HBc. The condition with isolated anti-HBs was different from those with isolated anti-HBc and both anti-HBc and anti-HBs as follows. The titer of anti-HBs in isolated anti-HBs positive samples was significantly lower than that in both anti-HBs and anti-HBc positive ones (46.2 +/- 5.4 vs. 83.2 +/- 2.8, mean +/- SE, p less than 0.001). The presence of isolated anti-HBs was neither significantly more frequent in males nor related to the risk of liver damages in contrast with that of anti-HBc with or without anti-HBs. These findings suggest that isolated anti-HBs pattern with the absence of anti-HBc in general population was not due to prior HBV infection, but due to natural immunization with HBsAg.

Adult↗
PubMed2004

[A population study of three Y-STR loci by multiplexing in Han population in Chengdu, China].

OBJECTIVE: To establish a better method determining three Y-STR loci. METHODS: A multiplex of Y-STRs and amplify simultaneously three Y-STRs loci. RESULTS: Establish successfully a multiplexing system of three Y-STR loci (DYS390, DYS391 and DYS393) followed by a population genetic study of Han population in Chengdu, China. CONCLUSION: The diversity of haplotype is 0.8965, the value of discrimination and the chance of exclusion chance is 0.8965 with the standard error 0.0081. This established system is one of the good tools in personnel identification and genetic study.

China↗
PubMedDate not supplied

Use of the ecosystem approach to population health: the case of mercury contamination in aquatic environments and riparian populations, Andean Amazon, Napo River Valley, Ecuador.

BACKGROUND: Driven by accelerating transformation of land use in the Amazon, studies addressing the impacts of deforestation and mercury (Hg) leaching on the geophysical, biological, social, health, economic and political systems of Amazonian countries are crucial to evaluate the population health risks of these rapid changes. METHODS: We used an ecosystem approach, integrating Hg measurements with socio-cultural and politico-economic elements, to provide an integral analysis and comprehensive solutions. RESULTS: Our interdisciplinary research in the Ecuadorian Andean Amazon has shown that comestible fish and riparian communities which rely on fish as a major protein source have mercury levels that could potentially cause subtle but deleterious population health alterations. A parallel study identified deforestation and soil erosion as a significant source of mercury to the aquatic ecosystem. INTERPRETATION: The analysis of these results in conjunction with the prevailing socio-cultural and politico-economic context allowed us to identify economic trends, and especially petroleum exploitation, as pivotal in the deforestation/mercury-exposure dynamic. In collaboration with public health authorities, we shared our results with local health stakeholders, including public health care staff, federal government agencies, researchers and local communities, in such a way as to promote sustainable land use practices and the nutritional benefits of fish eating while reducing toxic exposures.

Animals↗