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N Masurel

Publications and source records attributed to N Masurel.

At least 37 records · Page 2Linked to original sources
PubMed1993

Influenza vaccines: the effect of vaccine dose on antibody response in primed populations during the ongoing interpandemic period. A review of the literature.

Health authorities tend to favour an increase of the antigen dose in inactivated influenza vaccines from < or = 10 micrograms haemagglutinin (HA) per vaccine strain to 15 micrograms HA/strain. The increased dose is expected to yield a meaningful increase in the number of subjects to be protected after vaccination. To verify this expectation, we have reviewed 20 published reports (1978-1991) of serological studies in which anti-HA-IgG antibody after different doses was measured. In the review, stratification groups of previously primed subjects were formed and the antibody response was estimated for doses of 10 and 15 micrograms HA by linear k*2-chi 2 model. Despite a considerable heterogenicity of study populations, study designs, vaccine types and strains, and antibody assays, the results were consistent in revealing high protection rates (> or = 75%) for a 10 micrograms HA dose of influenza A vaccine components. For both response and protection rates, an increase of the antigenic load from 10 to 15 micrograms HA was not associated with a meaningful increase of seroresponse: in 38 out of 39 stratification groups, the increase of response and/or protection rate varied between -9% and +8%, with a median of 1.5%. These results do not justify the expectation that a vaccine dose of 15 micrograms HA per strain would be clinically superior to a dose of 10 micrograms HA. Only in a group of immune-compromised patients on chronic intermittent haemodialysis were results in favour of a higher dose found, which may justify further evaluation in this special population.

Adolescent↗
PubMed1993

Impact of influenza on mortality in relation to age and underlying disease, 1967-1989.

Based on data from the Dutch Central Bureau of Statistics, the impact of influenza on mortality in The Netherlands was estimated for a 22.5-year period (1967-1989) in four age groups and three entities of disease, using Poisson regression techniques. Our analysis suggests that, on average, more than 2000 people died from influenza in The Netherlands each year, but in only a fraction of these deaths was influenza recognized as the cause of death. For each case of death registered as caused by influenza (registered influenza mortality), 2.6 additional cases of death registered as due to causes other than influenza, nevertheless, were influenza-related (non-registered influenza mortality). Therefore, the overall impact of influenza on mortality is estimated to be greater than registered influenza mortality by a factor of 3.6. Those under 60 years of age accounted for 5% of all non-registered influenza deaths, whereas people aged 60-69, 70-79 years and > 80 years accounted for 12%, 29% and 54% of such deaths, respectively. When extrapolating the figures for the Dutch population of 1989, we could attribute, on average per season-year, 82 deaths per 100,000 people > 60 years, 143 in people > 70 years, and 280 in people > 80 years. Of all non-registered influenza cases of death, 47% were estimated to occur in people with heart disease as a primarily reported cause of death, 23% in those with lung disease, and 30% in those with other diseases. This study stresses the serious effects of influenza, mainly in the elderly (95% of non-registered influenza mortality).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Prospective application of reverse transcriptase polymerase chain reaction for diagnosing influenza infections in respiratory samples from a children's hospital.

A prospective clinical evaluation of the reverse transcriptase polymerase chain reaction (RNA PCR) for detection of influenza viruses was carried out with specimens from 342 patients of a children's hospital in The Netherlands. The RNA PCR, carried out directly on the specimens without an organic extraction, showed a sensitivity and specificity which are superior to those of direct immunofluorescence and comparable to those of cell culture combined with immunofluorescence (culture/IF). Negative results can be obtained within 2 days by the RNA PCR but may take up to 14 days by culture/IF. Because culturing is the standard technique for the detection of respiratory viruses, at this moment there are no strong arguments to replace culture/IF with RNA PCR for the detection of influenza A virus.

Base Sequence↗
PubMed1992

Type-specific identification of influenza viruses A, B and C by the polymerase chain reaction.

The aim of this study was to develop a polymerase chain reaction for specific detection of influenza A, B, and C RNA genomes. Three primer sets were selected from conserved regions of the genome coding for the non-structural proteins and were tested on 61 influenza A (22 H1N1, 9 H2N2, and 30 H3N2), 11 influenza B, and three influenza C isolates. Specific amplified products were obtained with all these strains after electrophoresis on a 2% agarose gel. The specificity of the reaction was increased by hybridization with oligonucleotide probes. When nucleic acids from a variety of micro-organisms from the respiratory tract were subjected to the PCR with these primers, no specific amplified products were generated. The sensitivity of the technique was found to be at the subpicogram level. The RNA-PCR was applied to 21 clinical specimens from patients with a culture/IF proven influenza infection. Six influenza A positive patients and 13 influenza B positive patients could be confirmed in the RNA-PCR. In two cases, influenza B positive IF specimens were found negative by the PCR. No virus could be isolated on eggs or tissue culture from these samples. RNA-PCR is a specific and sensitive technique for the detection of influenza virus genomes.

Base Sequence↗
PubMed1992

Influence of blood glucose levels on peripheral lymphocytes in patients with diabetes mellitus.

Abnormalities in lymphocyte subpopulations in patients with type 1 diabetes have been reported previously. To evaluate the effect of blood glucose levels on peripheral lymphocyte concentrations we studied the proportion and phenotypic composition of the T-cell population in 7 patients with type 1 and in 12 patients with type 2 diabetes at hospitalization because of metabolic dysregulation and in a period of restored control. Both the number of CD-4 and CD-8 positive cells increased significantly (p < 0.05), although no change in the CD-4:CD-8 ratio was observed. After restoring metabolic control there was a significant rise in the mean number of total lymphocytes (1760 +/- 759 x 10(6)/ml vs 2385 +/- 889 x 10(6)/ml, p < 0.05). The number of total lymphocytes increased in all patients but one. It is concluded that metabolic control can influence immunological parameters such as numbers of peripheral lymphocytes of various phenotypes.

Adult↗
PubMed1991

Effect of epidemic influenza on ketoacidosis, pneumonia and death in diabetes mellitus: a hospital register survey of 1976-1979 in The Netherlands.

The influence of epidemic influenza on hospitalizations because of influenza, pneumonia and diabetic acidosis in patients with diabetes mellitus was investigated. Data on the weekly incidence of influenza-like illness were obtained from the Continuous Morbidity Registration and the cumulative data on hospitalizations in short-stay hospitals were obtained from the National Medical Registration. Patients with duodenal ulcer were used as a control population. Epidemic elevations of influenza infections were observed in 1976 and 1978. The estimated relative risk for hospitalization because of influenza infection was 1.1 and 1.0 for the two non-epidemic years 1977 and 1979, respectively. For the epidemic years 1976 and 1978 this risk was calculated to be 5.7 and 6.2, respectively. An increased relative risk was also noted for pneumonia; being 25.6 for both epidemic years. The estimated relative risk of dying during hospitalization rose from 30.9 in 1977 to 91.8 in 1978. The number of hospitalizations for ketoacidosis was 50% higher in 1978 than in the other three years. During the epidemic years, 25.7% of patients hospitalized for pneumonia died, while this percentage was 14.6% in the non-epidemic years (P less than 0.05). Differences in mortality due to diabetic acidosis were similar: 25.4% in epidemic and 14.7% in non-epidemic years (P less than 0.01). During the 1978 epidemic, one out of every 1300 patients with diabetes mellitus was hospitalized because of pneumonia. It is estimated that 1 of every 260 patients with IDDM was hospitalized for diabetic acidosis. It is concluded that patients with diabetes mellitus have indeed a very high influenza-associated morbidity.

Diabetes Complications↗
PubMed1991

Influenza: relation of mortality to morbidity parameters--Netherlands, 1970-1989.

The purpose of this study is to investigate the relationship between the number of influenza-like illness (ILI), weekly registered by the general practitioners (sentinel stations), and the monthly overall influenza mortality in people over 60 years of age, provided by the Dutch Statistical Bureau during the period July 1970 to June 1989. The quantitative impact of influenza-morbidity is expressed by three summary parameters, calculated from the 52 (53) weekly ILI-figures per season-year, (i) their sum (i.e. global extent of an epidemic), (ii) their standard deviation, and (iii) their maximum (i.e. peak number of ILI during an epidemic). In the analysis influenza A subtype is also included. These four parameters are mutually compared with respect to their predictability for yearly total influenza mortality in the 19 season-years available. In most cases, the standard deviation and the peak number of ILI are more powerful for prediction of mortality, than the global extent of the epidemic. The peak number of ILI is of special interest. It is particularly useful for estimating the effect on current influenza mortality during an ongoing epidemic. From the model it is possible to calculate a threshold (of weekly ILI) beyond which mortality increases proportionately more than the number of illness episodes. By using the peak value of morbidity it is possible to calculate the minimal impact of epidemic mortality. This study indicates that the weekly number of influenza-like illnesses has a certain prognostic value for the real impact of influenza. An electronic surveillance system could detect immediately the threshold above which influenza mortality increases more than proportionally.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Effect of immunomodulator thymopentin on impaired seroresponse to influenza vaccine in patients on haemodialysis.

In a double-blind placebo-controlled multicentre study, the effect of the immunomodulator thymopentin (TP5) on the antibody production to trivalent influenza vaccine was tested in 108 patients on chronic intermittent haemodialysis (HD). Antibody production was determined in pre- and postvaccination sera. Compared to a group of 35 young healthy adult control subjects, HD patients showed a clearly impaired seroresponsiveness to all three vaccine components, regardless of treatment with TP5 or placebo. We conclude that TP5 administration is not able to enhance humoral immunity in patients on chronic intermittent HD.

Adolescent↗
PubMed1990

No evidence for the enhanced production of insulin autoantibodies after confrontation with common viral antigens in insulin dependent diabetes mellitus.

The production of insulin autoantibodies (IAA) was studied after common viral infections in 12 children with type 1 diabetes mellitus and in their 18 healthy siblings. In addition, the production of IAA was measured after influenza vaccination with booster in 39 patients with type 1 diabetes mellitus and in 39 healthy controls. In 7 of the 12 diabetic children 13 viral infections were serologically confirmed. Among the siblings 14 periods of infection were noted in 9 individuals. A significant rise in IAA antibody titre was demonstrated in patients twice (IgG both times) and in siblings 11 times (IgM 5x, IgG 6x, difference significant P less than 0.05). In only three cases the rise in antibody titres occurred 6-12 wk after documented infection. There was a significant inverse correlation with age in both patients (r = 0.89, P less than 0.0001) and siblings (r = 0.67, P less than 0.001) for IgM IAA. After influenza vaccination a significant increase in IAA was noted twice: IgM IAA in a patient with diabetes and IgG IAA in a healthy volunteer. A four-fold decrease in IgG IAA was demonstrated in one diabetic patient. From these results it is concluded that IAA formation is not a direct sequela of viral infection or vaccination.

Adolescent↗