Study of cholesterol-lowering effect and safety of simvaglisin on rabbit model of hypercholesterolemia.

Using rabbit model of experimental hypercholesterolemia we showed that the hypocholesterolemic effect of simvaglisin, a complex preparation containing simvastatin and glycyrrhizic acid, in doses corresponding to 40, 66.5, and 100 mg/kg/day simvastatin is equal to the hypocholesterolemic effect of 200 mg/kg/day simvastatin alone. The total blood cholesterol decreased by 39, 36, 47, and 38% (p < 0.05), respectively, after 20-day course of the preparation. Myotoxicity of simvaglisin evaluated by serum creatine phosphokinase was lower than that of simvastatin. After 30-day treatment, this parameter was lower by 26, 24, and 29% (p < 0.05) than the corresponding parameter for simvastatin.

Risk factors for Alzheimer's disease in Russia: a case-control study.

No reliable data on risk factors of Alzheimer's disease (AD) are available in Russia. We aimed to evaluate the relative importance of various putative environmental and medical risk factors of AD in a Russian population. We conducted a hospital-based case-control study. Two hundred and sixty consecutive AD patients and an equal number of cognitive impairment-free control subjects matched for sex, age, level of education and place of birth selected from nursing homes and other long-term healthcare facilities in the Novosibirsk region for the period from 1998 to 2002 were examined. A conditional logistic regression analysis was employed to calculate odds ratios (OR) and corresponding 95% confidence intervals (CI) for various putative risk factors. Of the 260 patients with AD, 187 (72%) were females. Patients' age varied from 40 to 89 years (mean +/- SD: 69.2 +/- 7.7 years). The majority of the patients (77%) had secondary education and 12% had university education. Risk factors independently associated with AD were family history of parkinsonism among first-degree relatives (OR = 4.2; 95% CI 1.2-15.1), hypothyroidism (OR = 2.7; 95% CI 1.1-6.7), and history of head trauma with loss of consciousness (OR = 1.7; 95% CI 1.0-2.8). The most important risk factors for AD in the Russian community are family history of parkinsonism, hypothyroidism and a history of head trauma with loss of consciousness. These findings have implications for developing preventive strategies of AD.

Plasma lipoprotein (a) levels and Apo(a) isoforms in native population of Chukotka with and without arterial hypertension.

Lipoprotein(a) (Lp(a)) levels and Apolipoprotien(a) (Apo(a)) isoforms in blood plasma were determined among the native population of Chukotka (Chukchee, Eskimo) in 32 persons with and 148 persons without Arterial Hypertension (AH). Plasma Lp(a) levels were determined by radial immunodiffusion using polyclonal antibodies raised against purified Lp(a) human plasma. The range of fluctuations of Lp(a) levels was wide: 0-77 mg/dl (Chukchee), 0-48 mg/dl (Eskimo). The distribution in the total population was also highly skewed, yielding a curve similar to a negative exponential function. Insignificant differences were found in the levels of Lp(a) between persons with and without AH: 22.9 +/- 2.6 vs. 20.6 +/- 0.8 mg/dl. Apo(a) isoform S4 as homozygous appears to be more frequent in patients with AH (8.1%), than in persons without AH (15.3%), isoform S2 in 30.2% and 19.2%, isoform S1 in 3.9% and 2.9%, respectively (in all cases p > 0.05). In conclusion, plasma Lp(a) levels in native population of Chukotka (Chukchee, Eskimo) did not differ between persons with AH and without AH. Apo(a) isoform distribution differed slightly between Chukchee and Eskimo with AH and without AH.

Leukogram and white blood cells count in native people of Chukotka.

A representative sample of male and female Chukotka natives aged 25-6 years (362 persons) has been surveyed using the cross-sectional epidemiological method. The results have been compared with the data obtained when surveying a representative sample of the non-organised population of the same age in Novosibirsk (n = 2071 persons). The mean age was 43 years. The total count of white blood cells (WBC) in peripheral blood of Chukotka natives was lower than the corresponding values of that index in the inhabitants of Novosibirsk, the 10-90% range of white blood counts being 3.0-7.0 10(9)/l in natives and 4.0-9.0 10(9)/l in residents of Novosibirsk. A significant incidence of leukopenias (<4.0 10(9)/l) has been detected, being 30% in the population of Chukotka, 24% in men and 35% in women. Modification in White Blood Cells differentials (leukogram) has been found in native Chukotka people, particularly relative and absolute lymphocytopenia.

A population-based study of the associations of stroke occurrence with weather parameters in Siberia, Russia (1982-92).

Previous studies have established a seasonal variation in stroke occurrence, but none have assessed the influence of inclement weather conditions on stroke incidence in a general population of Russia. We performed a stroke population-based study in the Oktiabrsky District of Novosibirsk, Siberia, Russia. Included in the analysis were 1929 patients with their first occurrence of ischemic stroke (IS), 215 patients with their first occurrence of intracerebral hemorrhage (ICH) and 64 patients with their first occurrence of subarachnoid hemorrhage (SAH): all patients were aged between 25 and 74 years. The cumulative daily occurrence of total strokes and stroke subtypes was evaluated in relation to aggregated daily mean values of ambient temperature, relative humidity and air pressure by means of Poisson regression analysis to estimate the rate ratio (RR) with corresponding confidence interval (CI) and to identify the weather parameters of most importance. In a multivariate analysis, with adjustment for the effects of season, solar and geomagnetic activity, and age of the patients, low ambient temperature (RR 1.32; 95% CI 1.05-1.66) and mean value of air pressure (RR 0.986; 95% CI 0.972-0.999) were important predictors of IS occurrence, while mild ambient temperature (RR 1.52; 95% CI 1. 04-2.22) was an important predictor of ICH occurrence. No relationship between SAH occurrence and any one of the weather parameters studied was revealed. There was no interaction between any meteorological variables that was statistically significant. Inclement weather conditions are associated with the occurrence of IS and ICH in Siberia, Russia. Among the meteorological parameters studied, low ambient temperature and mean air pressure are the most important predictors of IS occurrence, whereas the occurrence of ICH is associated with mild ambient temperature. There is no association between any one of the weather parameters studied and the occurrence of SAH.

A population-based study of transient ischemic attack incidence in Novosibirsk, Russia, 1987-1988 and 1996-1997.

BACKGROUND AND PURPOSE: Population-based data on transient ischemic attack (TIA) incidence are scarce. This study defines incidence rates of first-ever TIA in Novosibirsk, Russia, during 1987-1997 and compares the incidence of first TIA with that of first stroke. METHODS: This is a prospective registry population-based study of all new cases of TIA and stroke in an overall population of 455 765 residents of Novosibirsk. All new TIA and stroke incident cases (whether inpatient or outpatient) that occurred during 1987-1988 and 1996-1997 study periods were recorded and analyzed. A 95% CI was estimated for all age- and sex-specific strata. RESULTS: During the 2 study periods, a total of 211 patients with first TIA were registered in the population studied. The crude annual TIA incidence rate per 100 000 residents was 16 (95% CI, 8 to 33) in 1987-1988 and 29 (95% CI, 9 to 87) in 1996-1997; these rates standardized to the European population were 17 (95% CI, 8 to 34) and 27 (95% CI, 9 to 79), respectively. Eighty-three percent of TIAs occurred in the carotid arteries (rate, 48/100 000), 10% occurred in the vertebrobasilar territory (rate, 6/100 000), and 7% of cases had a TIA of uncertain distribution (rate, 2/100 000). CONCLUSIONS: Unlike stroke incidence rate, the incidence rate of TIA in Novosibirsk is similar to that in other populations and constitutes approximately 10% of stroke incidence. For the last decade (1987-1997), there was a tendency, although statistically insignificant, toward increasing incidence rate of TIA in the population studied.

Risk factors for ischemic stroke in a Russian community: a population-based case-control study.

BACKGROUND AND PURPOSE: This study was conducted to determine the risk factors for ischemic stroke in a defined Russian population. METHODS: Our data are based on a population-based case-control study of 237 patients with first-ever ischemic stroke and 237 age- and sex-matched controls. Logistic regression methods for matched pairs were used to estimate the relative risk for the variables studied. RESULTS: In a multivariate analysis, hypertension, left ventricular hypertrophy on electrocardiography, ischemic heart disease, mitral valve disease, current cigarette smoking, and high body mass index were significant and independent risk factors for ischemic stroke in this Russian community. CONCLUSIONS: The significant risk factors for ischemic stroke in Novosibirsk are similar to those from other populations and cohorts. This study, the first of stroke risk factors in Russia, has implications for clinical practice and the planning of stroke prevention in the population.

Helicobacter pylori in a Chukotka Native male population.

Helicobacter pylori (HP) is a widespread human pathogen closely associated with gastroduodenal diseases. Thirty-four males from one of the settlements of coastal Chukotka (72% of total adult male population, mean age 31.6 years) underwent upper endoscopy, and HP was examined histologically in antral biopsies (Giemsa stain). Histology revealed normal mucosa in 16%, antral superficial gastritis in 29%, and atrophic gastritis in 55%. HP was found in 40% of histological specimens of normal mucosa, in 100% of superficial gastritis, and in 77% of atrophic gastritis. Correlation was found between the degree of bacterial contamination and both the activity of gastritis and grade of mononuclear infiltration. Data indicate a high prevalence of HP among Chukotka Natives (77%) which may partly explain the significant frequency of antral gastritis in this population.

Dietary fat and disease patterns in Chukotka Native adults.

It is well documented that dietary patterns have been changing for northern indigenous peoples as they adapt to a contemporary lifestyle. Recent dietary research among Chukotka Native adults showed a higher intake of saturated fatty acids (15% of energy) and sugar, and lower content of polyunsaturated fatty acids (5%) compared with our previous studies. We showed a higher percentage of dietary fat from animal fats (31%) and meat products (28%) than from seafoods and fish, which provide only 11% of daily fat intake. Increasing use of marketed foods and decreasing consumption of traditional foods among Chukotka Native adults contribute to more frequent cases of overweight, diabetes mellitus, and cancer. Dietary recommendations with an emphasis on traditional eating patterns should be considered for promotion of a healthy diet in Chukotka inhabitants. Promoting local foods of high biological value and establishing educational nutrition programs are of great importance.

Determination of the fraction composition of blood lipoproteins by the small-angle X-ray scattering technique.

A new method for analyzing the fraction composition of blood lipoproteins (LP) was developed based on the small-angle X-ray scattering (SAXS) technique. The method allows quantitative determination of the contents of basic LP fractions (high-density LP, low-density LP, very low-density LP and their subfractions) in the blood plasma or serum. The results of LP analysis by the new method were compared with electron microscopy, ultracentrifugation and gel electrophoresis data. The results obtained by SAXS correlated with those obtained by traditional methods. The new method for the determination of the LP fraction composition in the blood is rapid (1-1.5 h), uses only one reagent (e.g., sucrose) and features a high accuracy and resolution up to LP subfractions. A total of 0.05 ml of the blood plasma or serum is required for an assay. The assays can be carried out in purified preparations or in the blood plasma or serum. The method developed can be used in clinical practice for diagnostics and in scientific research.

Cancer in Russian Inuit.

Using the framework of the Native Cancer Registry, cancer morbidity among Russian Inuit can be obtained from 1960 onwards. Earlier data are available, but have not been verified. Unfortunately, the absence of accurate demographic data for the Native population of about 16 000 people, including the increase from 1 149 to 1 452 Inuit between 1970 and 1989 prevents comparison and analysis of morbidity and mortality data with the non-Inuit population. Nevertheless, the number of cancers has risen in the Native population of Chukotka during the last decade (1979-1988), with a predominance of oesophagus, lung and stomach cancer among the Inuit. In contrast, no cases were observed of the salivary gland, nasopharyngeal and cervical cancers common in other Inuit populations.

Stroke epidemiology in Novosibirsk, Russia: a population-based study.

OBJECTIVE: To determine first-ever stroke incidence, 30-day case-fatality rates, and frequency of various risk factors among patients with stroke in Novosibirsk, Russia, during 1992. DESIGN: A population-based study of an administratively defined district of Novosibirsk was conducted to identify residents with a first-ever stroke that occurred between Jan. 1, 1992, and Dec. 31, 1992. MATERIAL AND METHODS: For case ascertainment, mortality statistics, death certificates, hospital registrations, outpatient clinical data, and all ambulance calls for the study area were reviewed. Patients with stroke or suspected stroke were examined and interviewed by a cerebrovascular neurologist, and the type of stroke was determined. RESULTS: During the 12-month study period, 366 patients with first-ever stroke were registered. A diagnosis of cerebral infarction or intracerebral hemorrhage was confirmed by computed tomography or autopsy in 42% of cases. The diagnosis of subarachnoid hemorrhage was established by cerebrospinal fluid examination in all 14 cases. The age- and sex-adjusted annual incidence rate for stroke was 232 per 100,000. The distribution of incidence cases by diagnostic category was as follows: cerebral infarction, 87.7%; intracerebral hemorrhage, 8.5%; and subarachnoid hemorrhage, 3.8%. The overall 30-day case-fatality rate for stroke was 22.4%. Hypertension, angina pectoris, and cigarette smoking were the most frequent risk factors in patients with stroke in Novosibirsk. CONCLUSION: The incidence rate of first-ever stroke in Novosibirsk, Russia, is one of the highest in the world, but the 30-day case-fatality rates are similar to those in other populations.

Alcohol consumption and flushing response in natives of Chukotka, Siberia.

OBJECTIVE: Drinking patterns and flushing response were investigated among indigenous natives of Chukotka, Siberia (162 women, 139 men). The quantification of drinking behavior could be used for comparison with other northern peoples and as a baseline for future intervention. METHOD: Interviews, physical examinations and blood tests were performed in the Chukotka region of Siberia. RESULTS: 28% of the men and 4.5% of the women drank at least once per week. High doses per typical drinking occasion, which averaged 177.6 g of pure alcohol in men and 74.3 g in women, were reported; 10.3% of the men and 25.5% of the women reported that they experienced facial flushing after drinking. In most cases more than 20 g of alcohol was necessary to induce flushing, and two-thirds of the flushers were able to continue drinking after flushing began. No significant relationship between flushing and frequency and quantity of drinking and the prevalence of alcohol-related symptoms was found. There was a significant association between flushing by women and reports by them of their parent's flushing. CONCLUSIONS: Flushing by Chukotka natives and its relationship to drinking behavior is different from Oriental ALDH2-deficient flushing.

Prevalence and risk factors of iron-deficiency in women of Chukotka.

A study of iron deficiency states (IDS) in Chukotkan native women aged 20-59 years revealed a relatively high prevalence of 36.4%. The prevalence of anemia was 5.6%. Some risk factors of IDS have been defined including frequent deliveries, prolonged lactation and also some peculiarities in the nutrition of these women.

Prevalence of diagnosed diabetes in circumpolar indigenous populations.

The prevalence of diagnosed diabetes in several genetically closely related indigenous populations in the circumpolar arctic and subarctic regions of Russia, Alaska and Canada is compared. The age-standardized (to the IARC's hypothetical world population) prevalence ranged from 1.8/1000 among the Chukchi and Eskimo of Chukotka, 3.6 and 7.9/1000 among the Eskimos/Inuit of the Canadian Northwest Territories (NWT) and Alaska respectively, 7.1, 9.3 and 18.6/1000 among Athapaskan Indians in the NWT, Yukon and Alaska respectively, to a high of 22.7/1000 among the Aleuts in Alaska. All are below the US all-race prevalence of 23.5/1000 and far below the extreme high prevalence reported from many North American Indian tribes. As a group, such arctic and subarctic peoples have a much shorter and less intense history of European contact and acculturation. Environmental factors are also likely to be responsible for the current differences between these indigenous populations in the circumpolar region, assuming that they share susceptibility genes for diabetes inferred from their close genetic relationships based on markers in other loci. Formal surveys of glucose tolerance and potential risk factors such as diet, physical activity, obesity, insulin resistance and genetic admixture in the circumpolar region would improve knowledge of the aetiology of diabetes in genetically and culturally diverse human populations.

Comparison of diets in two native Chukotka populations and prevalence of ischemic heart disease risk factors.

Epidemiological studies of nutrition and the prevalence of ischemic heart disease risk factors were carried out comparing native Markovskaya populations living in the tundra and coastal areas. There was lower prevalence of IHD risk factors among 30-59 year old males in coastal villages than in a comparable population residing in the tundra. This finding can be partially explained by analysis of the diets of both regions. Although the coastal natives' diet was higher in calories and fats than tundra inhabitants'; it was rich in polyunsaturated fatty acids, the main source of which was sea-animal meat.

The validation of serum thiocyanate smoking data in a population survey.

The estimation of smoking using blood serum thiocyanate concentration definition was performed in a representative sample of the population of the city of Novosibirsk. 1741 men and 1665 women aged 25-64 were surveyed. The concentration of blood serum thiocyanate increases with the number of cigarettes smoked, and depends on the time interval from the last smoking to the moment of taking the blood sample. It was shown that, as far as men are concerned, there is general agreement between the data obtained from the questionnaire on smoking and the data obtained through the biochemical estimation of inhaled tobacco smoke. In women, a discrepancy was noted between the data obtained using these two different methods.

Comparative data on diet and risk factors from five Eastern European communities.

Starting from large differences in rates and trends of mortality between European countries, an ecological type of comparative study was launched between five population samples in so-called Eastern European countries: Krakow, Warsaw, Novosibirsk, Kaunas, and the German Democratic Republic (GDR). The purpose was to look into dietary data as a possible explanation for varying risk factor and mortality data. It was found that high energy and fat consumption but low carbohydrate intake are common in these populations. The sources of energy and fat however vary markedly. An association was found between diet-related cardiovascular risk factors like the mean total cholesterol value and excess energy or fat intake both in males and in females. It was concluded that changes in diet might be the most important prerequisite for a number of lifestyle changes in these communities, and that those diet changes need to be monitored on a regular basis as part of the national health reports.

Arterial-wall tissue factors influencing haemocoagulation, and their release into circulation in endarterectomy.

The wall of lover-limb arteries affected with severe atherosclerosis contains a Complex of substances with pro- and anticoagulative activities. The arterial wall, traumatized in endarterectomy by separation of the individual coats, releases procoagulative substances into blood circulation. The most conspicuous local manifestations of hypercoagulation and hypofibrinolysis appear on the day of surgery. The artery operated upon releases the thromboplastic factor for nine days; substances shortening the thrombin time (antiheparin substance, thrombin accelerator), for five days; and inhibitors of fibrinolysis, for four days after operation. A correlation was found between the regenerative process in the endarterectomized artery and the dynamics of the release of tissue factors influencing the haemocoagulation.