Biomedical subjects

C Benes

Publications and source records attributed to C Benes.

At least 19 recordsLinked to original sources

PubMed2005

[Longitudinal epidemiology of leptospirosis in the Czech Republic (1963-2003)].

After higher rates of occupational or leisure diseases recorded in the Czech Republic in the second half of the last century it was found that the last climatic changes and catastrophic floods of 1997 and 2002 were followed by outbreaks of leptospirosis as the only re-emerging postflood infection. While in tropics and subtropics the monsoon season is typically followed by highly increased rates of leptospirosis in humans, even, with fatal outcomes, this phenomenon remained unknown under the climatic conditions of the Czech Republic where human leptospirosis has been reported rather sporadically, mostly in natural foci of infection, and its incidence rate is usually about 0.3% per 100,000 population. Nevertheless, after the unexpected vast floods of 1997 and 2002 that also afflicted natural foci of leptospirosis, the rates of reported and serologically confirmed cases of leptospirosis in the Czech Republic were three times as high as usual with the specific morbidity reaching 0.9 case per 100,000 population. In 1997, as many as 7156 persons were tested for leptospirosis in the Czech Republic: the disease was diagnosed and reported in 94 patients and in 2002, 92 out of 4999 persons tested were diagnosed with leptospirosis. Two thirds of these cases were from inundation areas, half of them being directly associated with floods (exposure to residual water, flood mud in cellars, etc.). Four case of Weil disease reported in 1997 were fatal. As many as 41 deaths from Weil disease have been reported in the Czech Republic since 1963 when the disease became reportable.

Czech Republic↗

PubMed2004

Socio-economic conditions and other anthropogenic factors influencing tick-borne encephalitis incidence in the Czech Republic.

Laboratory confirmed cases of tick-borne encephalitis (TBE) have been reported in the Czech Republic since 1971. Peaks of incidence occurred at 2 to 5-year intervals. The incidence in the eighties was generally lower than in seventies. In the nineties there was a sharp increase in incidence that peaked in 1995 (7.2/100,000). TBE cases occur from April to November with maximum incidence in July. During the last decade the second peak of incidence occurred in most years in September and/or October. In the last decade, an extension of the TBE season towards the spring and autumn periods has been observed. In addition to a general increase in TBE incidence in the last decade, some other changes in the epidemiology of TBE were observed in the Czech Republic. During the whole period sex-specific incidence was higher in men than in women (men to women ratio 1.5:1). Age-specific incidence over recent years increased steadily in children and adolescent age groups. In the ten-year age groups from 25 to 65, it remains practically at the same level (6-8/100,000). In older persons it fell to 2-3/100,000. Tick bites infect patients mainly during their recreational activities. A very small proportion (less than 1%) acquires the infection through the alimentary route. We have tested the hypothesis whether the increase in TBE incidence in the nineties was due to economical or social changes after the velvet revolution of 1989. Between 1991 and 1995 unemployment largely remained on the same level (between 2-3%). Over the next years the percentage of unemployed persons increased rapidly to 9.3% in 1999 (7.8% in 2001). This trend differs significantly from the trend of TBE incidence that peaked in 1995. No correlation between the district incidence of TBE and the district percentage of unemployment in the years 1997-2001 was found (r=-0.20). The percentage of unemployed persons among the TBE cases was 1-3% in contrast to the Czech Republic figures which were 5-9% for the same period. The gross domestic product in USD per capita increased from dollars 2,600 in 1991 to dollars 5,000 in 1995. Since then it has varied between dollars 4,800 and dollars 5,600. This trend, therefore, differs from the trend of TBE incidence as well. Among the TBE cases the percentage of foresters and other persons working in the forests in the years 1997-2001 was 0.5-1%. The behavioral and socio-economic aspects of TBE cases remained stable despite the political changes which have take place in the Czech Republic since the beginning of the nineties. They are not, therefore, responsible for the increased TBE incidence. In the industrial areas most polluted by SO2 in the past in northern Bohemia the sharp increase in TBE incidence seems to be connected with measures aiming to eliminate SO2 emissions from brown coal power stations.

Adolescent↗

PubMed2004

[Trends in the incidence of salmonellosis and campylobacteriosis in the Czech Republic].

Salmonellosis and campylobacteriosis are the most frequently reported acute enteric diseases of infectious origin in the Czech Republic. Epidemiological data on salmonellosis and campylobacteriosis have been reportable in this country since 1951 and 1984, respectively. In 2003, 53,486 cases of acute enteric infections were reported: 26,899 (52%) diagnosed as salmonellosis and 20,063 (almost 40%) diagnosed as campylobacteriosis. In 1989, the annual incidence of salmonellosis was three times as high as in the previous year, the upward trend continued until 1995 (528/100,000) and since 1998 the salmonellosis incidence rates have been declining. The incidence of campylobacteriosis showed a progressive increase since 1984 to peak in 2002 with a following slight decline in 2003. Morbidity from salmonellosis and campylobacteriosis is highest in the age group 0-4-year-olds. The most frequent causative agents are Salmonella Enteritidis (96%) and Campylobacter jejuni, respectively. Both infections are foodborne. Ready-to-eat meals, poultry, confectionery and eggs seem to be most frequently implicated in outbreaks of salmonellosis in public catering and families. Sporadic cases of campylobacteriosis are mostly associated with ingestion of poultry and chopped meat. The incidence rates of these two infections are positively correlated with the average daily temperatures.

Acute Disease↗

PubMed2004

[Effects of climate change on the incidence of tick-borne encephalitis in the Czech Republic in the past two decades].

The study objective was an attempt to explain uneven distribution of the incidence of tick-borne encephalitis (TBE) throughout the past two decades. A sharp rise was recorded in the last decade: while 2596 TBE cases were reported in the decade 1983-1992, as many as 5892 TBE cases were reported in the decade 1993-2002, with high rates persisting also in the following years (606 TBE cases reported in 2003). Data from the database TBE EPIDAT of the National Institute of Public Health, Prague, and that of the Communicable Diseases Information System, Ostrava, were used for analysis. Meteorological data were taken from the database of the Czech Institute of Hydrometeorology, Prague. In 1971 to 2003, 13 231 laboratory confirmed TBE cases were reported in the Czech Republic. Uneven distribution of these TBE cases in time is consistent with the observations of climate variation made between 1931 and 2000. The increase in the TBE incidence in the Czech Republic in the last decade was characterized by the following features: 1) higher rates of TBE cases manifested in regular TBE natural focuses, 2) reemergence of TBE in the same localities after 20 and more year intervals and 3) emergence of TBE in localities where it was not reported before. At the same time shifts in TBE seasonal trends (i.e. to March and October-November) were observed, associated with a TBE incidence peak in autumn. Field research revealed that the major factor are the climate-related changes in ecology of the TBE vector Ixodes ricinus and resulting variation in its population density. TBE emergence in new areas is linked to the occurrence of ticks Ixodes ricinus at higher altitudes (previously found at 700 m and currently spreading to 1200 m) as well as to a coming warm climate era.

Czech Republic↗

PubMed2003

[Multiresistant Salmonella enterica subspecies enterica serovar Typhimurium DT104 in the Czech republic 2000-2001].

Salmonelloses belong to the most important alimentary diseases. From 1989 the main source of infection is S. Enteritidis (95% and more). The ratio of S. Typhimurium in the etiology declined gradually since 1994 from 3% in 1993 to 1.9% in 2001. The number of detected multiresistant strains STM DT104 is so far low in the Czech Republic. In 2000 laboratory tests confirmed 53 and in 2001 a total of 63 strains. Analysis of these strains revealed: 1. the proportion of multiresistant strains STM DT104 of the total number of isolated STM strains increased from 7% in 2000 to 11.5% in 2001, 2. the territory in the CR where these multiresistant strains were found expanded, 3. the relationship of proportions of the most frequently detected STM phagotypes in the human population changes: in 2000 this ratio was balanced, in 2001 the ratio of phagotype DT104 is roughly three times higher than of DT 141, 4. analysis of all STM strains from the environment and animals indicates that the frequency of STM DT104 is 73%. Almost 90% of these strains are multiresistant (resistant to one or several antimicrobial substances). The highest number was found in calves, piglets but also in poultry. With regard to the results of the submitted work it is important to concentrate attention on detection and further laboratory examination of STM strains in the human and animal population.

Adolescent↗

PubMed2003

The 2001 serological survey in the Czech Republic--measles.

In total, 3,013 sera from a representative population sample of the Czech Republic aged from 1 to 64 years were tested according to the requirements of the ESEN 2 project using a commercial kit Measles IgG (II) EIA manufactured by Denka Seiken, Japan. The highest seropositivity rate and GMT values were found in the population group aged over 35 years coming into natural contact with the causative agent. Among the vaccinee population, the best outcomes were achieved in 2-9-year-olds (seropositivity rate: 94-100%, GMT: 2500-4000 EIA) and 10-14-year-olds (seropositivity rate: 93-97.1%, GMT almost 2000 EIA). The lowest seropositivity rate was found in the age group 20 to 24 years, more precisely in the 20-year-olds (78.4%), vaccinated with only one dose before the end of the first year of life. The seropositivity rates and GMT values vary with the vaccination strategies adopted in different years. The morbidity trend is supportive of the appropriateness of the vaccination strategy selected.

Adolescent↗

PubMed2003

The 2001 serological survey in the Czech Republic--rubella.

In total, 3,009 sera from a representative population sample of the Czech Republic, 1508 females and 1,501 males, were tested by EIA using a commercial kit ETI-RUBEK-G Plus manufactured by Dia Sorin, Italy. The vaccination strategy was as follows: vaccination of 12-year-old girls since 1982 and all 2-year-olds vaccinated since 1986. Currently, all women under 31 years of age and all men under 17 years of age have been vaccinated. The results of the serological survey confirmed lower seropositivity rates in young men compared to vaccinated women of the same age as expected. An epidemic outbreak of rubeola among young men is another evidence of that The seropositivity rate of 2- 9-year-old vaccinee children reaches almost 95%. The long-term morbidity trend in the Czech Republic is downward sloping, with a marked differentiation between the male and female populations.

Adolescent↗

PubMed2003

The 2001 serological survey in the Czech Republic--mumps.

In total, 3,010 sera from a representative population sample of the Czech Republic aged from 1 to 64 years were tested according to the requirements of the ESEN 2 project using a commercial kit Mumps IgG (II) EIA manufactured by Denka Seiken, Japan. To date, the regular programme of vaccination against mumps has covered the population of children under 15 years of age. The vaccination coverage achieved (97-100%) does not correspond to the antibody prevalence rates of 70.2 to 86.4% as found. After implementation of regular vaccination in 1987, the morbidity rates have fallen dramatically. Nevertheless, the collective immunity achieved is not sufficient to prevent epidemics of mumps.

Adolescent↗

PubMed2002

[Incidence of S. typhimurium in the Czech Republic 1999-2001].

The ratio of serovars of S. Typhimurium among notified cases of salmonelloses in 1999-2001 did not exceed 3% and so far has a slightly declining trend. On a long-term basis the highest morbidity rate caused by this agent is reported in the South Moravian region. The age distribution and specific morbidity is highest in 1-4-year-old children, the seasonal incidence is highest, in the summer months. The most frequently suspected vehicles are eggs, poultry and meat products, in 1999 for the first time as a vehicle a grilled piglet was reported, in a total of three epidemics. Epidemiological analysis of salmonelloses caused by S. Typhimurium revealed that in the CR individual characteristics do not differ from those caused by S. Enteritidis and that the epidemiological situation as regards this serovar is, so far quiescent.

Adolescent↗

PubMed2001

Modulation of PKCdelta tyrosine phosphorylation and activity in salivary and PC-12 cells by Src kinases.

Protein kinase C (PKC) delta becomes tyrosine phosphorylated in rat parotid acinar cells exposed to muscarinic and substance P receptor agonists, which initiate fluid secretion in this salivary cell. Here we examine the signaling components of PKCdelta tyrosine phosphorylation and effects of phosphorylation on PKCdelta activity. Carbachol- and substance P-promoted increases in PKCdelta tyrosine phosphorylation were blocked by inhibiting phospholipase C (PLC) but not by blocking intracellular Ca2+ concentration elevation, suggesting that diacylglycerol, rather than D-myo-inositol 1,4,5-trisphosphate production, positively modulated this phosphorylation. Stimuli-dependent increases in PKCdelta activity in parotid and PC-12 cells were blocked in vivo by inhibitors of Src tyrosine kinases. Dephosphorylation of tyrosine residues by PTP1B, a protein tyrosine phosphatase, reduced the enhanced PKCdelta activity. Lipid cofactors modified the tyrosine phosphorylation-dependent PKCdelta activation. Two PKCdelta regulatory sites (Thr-505 and Ser-662) were constitutively phosphorylated in unstimulated parotid cells, and these phosphorylations were not altered by stimuli that increased PKCdelta tyrosine phosphorylation. These results demonstrate that PKCdelta activity is positively modulated by tyrosine phosphorylation in parotid and PC-12 cells and suggest that PLC-dependent effects of secretagogues on salivary cells involve Src-related kinases.

Animals↗

PubMed2000

Control of occupational hepatitis B among healthcare workers in the Czech Republic, 1982 to 1995.

Occupational hepatitis B remains a threat to healthcare workers (HCWs) worldwide, even with availability of an effective vaccine. Despite limited resources for public health, the Czech Republic instituted a mandatory vaccination program for HCWs in 1983. Annual incidence rates of acute hepatitis B were followed prospectively through 1995. Despite giving vaccine intradermally from 1983 to 1989 and intramuscularly as half dose from 1990 to 1995, rates of occupational hepatitis B decreased dramatically, from 177 cases per 100,000 workers in 1982 (before program initiated) to 17 cases per 100,000 in 1995. Among high-risk workers, the effect was even more dramatic (from 587 to 23 per 100,000). We conclude that strong public-health leadership led to control of occupational hepatitis B among HCWs in the Czech Republic, despite limited resources that precluded administering full-dose intramuscular vaccine for much of the program. Application of a similar program should be considered for other countries in regions that currently do not have a hepatitis B vaccination program.

Czech Republic↗

PubMed2000

Activation of PKCdelta by tyrosine phosphorylation in rat parotid acinar cells.

Receptor- and nonreceptor-mediated stimuli produce increases in both PKCdelta tyrosine phosphorylation and activity in rat parotid acinar cells and other cells. In vivo and in vitro increases and decreases in tyrosine phosphorylation resulted in increases and decreases, respectively, of PKCdelta activity. These studies demonstrated that increases in PKCdelta activity by G protein-coupled receptors and other stimuli were controlled by alterations in tyrosine phosphorylation.

Animals↗

PubMed2000

[Diagnosis and notification of rotavirus infection in the Czech Republic].

In 1998 in 33 laboratories in the Czech Republic 1,223 rotavirus infections were revealed. The largest number of positive infections was recorded in children under the age of 3 years. The most frequent diagnostic procedure is latex agglutination which was used in 29 laboratories. In six departments the positive findings are reported directly to the appropriate epidemiological department. In the information system of the hygiene service, Epidat, in 1998 239 cases were reported, i.e. 19.5% of those confirmed by laboratory tests. The authors discuss the contemporary impact of rotavirus infections in the Czech Republic.

Child, Preschool↗

PubMed2000

[Salmonelloses in the Czech Republic 1989-1998].

In the Czech Republic in 1989 a triple increase of the incidence of salmonelloses was recorded: 34,435 cases. Since that year the morbidity trend varies between 400 and 500 cases per 100,000 population. The dominating agent (95% and more) is Salmonella Enteritidis PT8. The epidemic incidence was recorded on the whole territory of the Czech Republic mainly in Moravia and in the East Bohemian region. The specific morbidity is highest in 0 and 1-4 year-old children. The seasonal incidence has two peaks with the exception of 1997. During the period between 1989 and 1996 there was a significant increase of epidemics of salmonellosis in conjunction with food production incl. private confectionery shops, restaurants and the sale of foods in the streets. The most important vehicle are eggs and egg products, in particular confectionery. Salmonella Typhimurium DT104 is found only rarely in the Czech Republic. The first epidemic (15 cases) developed in 1998.

Adolescent↗

PubMed1999

Mode of regulation of the extracellular signal-regulated kinases in the pancreatic beta-cell line MIN6 and their implication in the regulation of insulin gene transcription.

Physiological concentrations of glucose that lead to Ca2+ entry and insulin secretion activate extracellular signal-regulated protein kinases (ERK1 and ERK2) in the MIN6 pancreatic beta-cell line. Here we show that this activation is inhibited by the down-regulation of protein kinase C (PKC) and by genistein, an inhibitor of protein tyrosine kinases. In contrast with results obtained in other cell types, neither the epidermal growth factor activity nor the Src family protein tyrosine kinases seem to be involved in the Ca2+-dependent activation of ERKs. inhibition of tyrosine phosphatases by vanadate leads to the activation of ERKs. As observed in the response to glucose, this activation is dependent on Ca2+ entry through L-type voltage-dependent Ca2+ channels. Thus the activation of ERKs in response to glucose depends on PKC and possibly on a tyrosine kinase/tyrosine phosphatase couple. To define the role of ERK activation by glucose we studied the regulation of transcription of the insulin gene. We found that this transcription is regulated in the MIN6 cells in the same range of glucose concentration as in primary islets, and that specific inhibition of mitogen-activated protein kinase kinase, the direct activator of ERK, impaired the response of the insulin gene to glucose. This was observed by analysis of the transfected rat insulin I gene promoter activity and a Northern blot of endogenous insulin mRNA.

Animals↗

PubMed1999

[Evaluation of time trends in the weekly count of diseases].

In routine systems investigating the morbidity according to diagnosis it is very useful to analyse the development in time (for example the development of weekly reports). This paper is concerned with the methodology of such analyses. In practice it appears that the number of cases depends on season. It stands to reason, that it is necessary to consider also long-term trends. In this paper two different approaches are discussed--the Box-Jenkins analysis, which describes the random error and the Method of Trend Decomposition which spread the number of cases into the systematic component (long term trend and seasonal effect) and random variability. The authors describe the method of smoothing the estimate of the time series by kernel estimate. In both approaches they use weekly reports from the whole Czech Republic of diagnoses viral hepatitis A, rubella and salmonellosis.

Czech Republic↗

PubMed1998

Rapid activation and nuclear translocation of mitogen-activated protein kinases in response to physiological concentration of glucose in the MIN6 pancreatic beta cell line.

MIN6 is one of the few pancreatic beta cell lines that respond to physiological concentrations of glucose by secreting insulin, and little is known about the triggered molecular mechanisms. We report below that the response to glucose in the MIN6 cells includes an activation of the p42 and p44 mitogen-activated protein (MAP) kinases (ERK2 and ERK1). This activation also occurred with the antidiabetic sulfonylurea glibenclamide and kainate, a specific agonist of a subtype of the ionotropic glutamate receptors, which depolarize the cytoplasmic membrane. The requirement for a calcium entry through the L-type voltage-gated channels and other characteristics of the regulation of the MAP kinase activity, such as the effect of the elevation of the cAMP concentration by forskolin, were similar to those of the secretion of insulin. However, the activation of the MAP kinases is not required for the secretion of insulin, inasmuch as this effect of glucose was not abolished when the MAP kinases were prevented from activation by PD098059, an inhibitor of the MAP kinase kinase. However, as the MAP kinases were translocated into the nucleus, they might be implicated in the calcium-dependent transcriptional response of the cells to glucose and thus regulate the expression of the insulin gene.

Animals↗

PubMed1998

Neurons in primary culture are less efficiently infected by Toxoplasma gondii than glial cells.

Infection by Toxoplasma gondii is asymptomatic, leading to an immune response that controls the disease. In immune-compromised patients, however, quiescent cysts can reactivate, leading to toxoplasmic encephalitis. We studied the infection of cells of the central nervous system in an attempt to understand the process leading to this complication. Primary cultures of rat hippocampal glial cells and neurons were infected with the virulent strain RH and examined by immunofluorescent microscopy after fixation of cells and staining with antibodies specific to the different cell types. After 24 h of infection, glial cells were highly infected and showed active division of the parasite. Neurons, on the other hand, were much less efficiently infected than glial cells, but actual penetration of the parasites was demonstrated by confocal microscopy. Whereas glial cells contained vacuoles with several parasites, the vacuoles observed in neurons usually contained one parasite or, rarely, two, indicating that the parasites inside neurons did not undergo active division. This was corroborated by determination of the incorporation of [3H]-uracil. Little is known about the mechanism of neuronal infection by Toxoplasma. The experimental setup used in this study should help to improve our understanding of neuronal infection and bring insight into the physiopathology of toxoplasmic encephalitis.

Animals↗