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N Regamey

Publications and source records attributed to N Regamey.

13 recordsLinked to original sources

Prospectively assessed incidence, severity, and determinants of respiratory symptoms in the first year of life.

Respiratory symptoms are common in infancy. Nevertheless, few prospective birth cohort studies have studied the epidemiology of respiratory symptoms in normal infants. The aim of this study was to prospectively obtain reliable data on incidence, severity, and determinants of common respiratory symptoms (including cough and wheeze) in normal infants and to determine factors associated with these symptoms. In a prospective population-based birth cohort, we assessed respiratory symptoms during the first year of life by weekly phone calls to the mothers. Poisson regression was used to examine the association between symptoms and various risk factors. In the first year of life, respiratory symptoms occurred in 181/195 infants (93%), more severe symptoms in 89 (46%). The average infant had respiratory symptoms for 4 weeks and 90% had symptoms for less than 12 weeks (range 0 to 23). Male sex, higher birth weight, maternal asthma, having older siblings and nursery care were associated with more, maternal hay fever with fewer respiratory symptoms. The association with prenatal maternal smoking decreased with time since birth. This study provides reliable data on the frequency of cough and wheeze during the first year of life in healthy infants; this may help in the interpretation of published hospital and community-based studies. The apparently reduced risk in children of mothers with hayfever but no asthma, and the decreasing effect of prenatal smoke exposure over time illustrate the complexity of respiratory pathology in the first year of life.

Asthma↗

[Acute asthma attacks in childhood].

The diagnosis of an acute asthmatic attack in a child is made on a clinical basis. The severity of the exacerbation can be assessed by physical examination and measurement of the transcutaneous oxygenation saturation. A blood gas analysis can be helpful in this assessment. A child with a severe asthma exacerbation should be promptly referred to an emergency department of a hospital. Oxygen should be given to keep the oxygen saturation above 92% and short-acting, selective beta-2 agonists should be administered. Beta-2 agonists can be delivered by intermittent nebulization, continuous nebulization or by metered dose inhaler (MDI) with a spacer They can also be given intravenously in patients who are unresponsive to escalating therapy. The early administration of systemic corticosteroids is essential for the management of acute asthma in children. When tolerated, systemic corticoseroids can be given orally but inhaled corticosteroids are not recommended. Oxygen delivery, beta-2 agonists and steroid therapy are the mainstay of emergency treatment. Hypovolemia should be corrected either intravenously or orally. Administration of multiple doses of ipratropium bromide has been shown to decrease the hospitalization rate in children and adolescents with severe asthma. Clinical response to initial treatment is the main criterion for hospital admission. Patients with failure to respond to treatment should be transferred to an intensive care unit. A critical aspect of management of the acute asthma attack in a child is the prevention of similar attacks in the future.

Acute Disease↗

Longitudinal sero-reactivity to human herpesvirus 8 (KSHV) in the Swiss HIV Cohort 4.7 years before KS.

The relationship between viral infection with Kaposi sarcoma-associated herpesvirus (KSHV) and the onset of Kaposi sarcoma (KS) in AIDS patients is incompletely understood. This study investigates the use of three serological assays to predict the development of KS in HIV-positive patients. Serially collected serum samples from 36 patients with KS and matched controls in the Swiss HIV Cohort Study (SHCS) were analyzed in a case control study. Three serologic assays to detect antibodies against KSHV (nuclear and membrane antigen immunofluorescence assay, N-IFA, M-IFA and ORF 65.2 ELISA) were used to determine the predictive value of KSHV-seropositivity. Serial samples from the cases were also analyzed to determine longitudinal patterns of seroreactivity and identify cases of seroconversion. Assay sensitivity for detection of KSHV antibodies was highest for M-IFA (83%), followed by N-IFA (74%) and 65.2 ELISA (52%). At the time of initial serum sampling (median 4.7 years before KS), only the N-IFA distinguished case and control sera (61% vs. 32%) and no assay was clearly predictive of subsequent onset of clinical KS. Moreover, an unexpectedly high rate of reversions to seronegativity were observed by N-IFA (27/33) as well as by 65.2 ELISA (11/26) in the longitudinal analysis. Analysis of the ORF65.2 ELISA index indicated that these reversions before the clinical onset of KS were associated with antibody levels that frequently hovered around the level of detectability. A marked increase in ORF 65.2 antibody titer occurred in a third of the patients at the time of KS diagnosis. Only two seroconversions were documented. KSHV infection within the SHCS is likely to have preceded HIV infection. KSHV infection alone is not highly predictive of KS development in this cohort of HIV-infected homosexual men as compared with matched controls. Three KSHV serologic assays, though sensitive at the time of clinical KS are inconsistently positive before the development of AIDS-related KS.

AIDS-Related Opportunistic Infections↗

Kaposi's sarcoma-associated herpesvirus serology in Europe and Uganda: multicentre study with multiple and novel assays.

A multicentre study was undertaken to define novel assays with increased inter-assay concordance, sensitivity, specificity and predictive value for serological diagnosis of human herpesvirus type 8 (HHV-8) infection. A total of 562 sera from European and Ugandan human immunodeficiency virus (HIV)-infected or uninfected individuals with or without Kaposi's sarcoma (KS) and blood donors were examined under code by 18 different assays in seven European laboratories. Sera from KS patients and all non-KS sera found positive by at least 70%, 80%, or 90% of the assays were considered "true positive." The validity of the assays was then evaluated by univariate logistic regression analysis. Two immunofluorescence assays (IFA) for detection of antibodies against HHV-8 lytic (Rlyt) or latent (LLANA) antigens and two enzyme-linked-immunosorbent assays (ELISA) (M2, EK8.1) for detection of antibodies against HHV-8 structural proteins were found to be highly concordant, specific, and sensitive, with odds ratios that indicated a high predictive value. When used together, the two IFA (Rlyt-LLANA) showed the best combination of sensitivity (89.1%) and specificity (94.9%). The performance of these assays indicate that they may be used for the clinical management of individuals at risk of developing HHV-8 associated tumours such as allograft recipients.

AIDS-Related Opportunistic Infections↗

Downregulation of Bcl-2, but not of Bax or Bcl-x, is associated with T lymphocyte apoptosis in HIV infection and restored by antiretroviral therapy or by interleukin 2.

The role of Bcl-2, Bax, and Bcl-x in the apoptosis of T lymphocytes in HIV-infected individuals was investigated. A strong correlation between Bcl-2 downregulation and spontaneous apoptosis has been reported by various groups in short-term cultures of CD8+ but not of CD4+ T lymphocytes. We describe a similar correlation in CD4+ T cells and provide an explanation why Bcl-2 downregulation in these cells has not been detected so far. In apoptotic cells not only Bcl-2, but also the CD4 surface receptors, are downregulated, preventing the detection of these cells in flow cytometric analysis. In contrast to Bcl-2, no correlation is detectable between Bax or Bcl-x expression and apoptosis. T lymphocytes of HIV-infected, but not of control, individuals display ex vivo a heterogeneous Bcl-2 expression pattern with a low and a high Bcl-2-expressing lymphocyte fraction. The proportion of low Bcl-2-expressing T cells correlates with a higher viral load in these individuals. Antiretroviral therapy significantly reduces the proportion of low Bcl-2-expressing lymphocytes, which is associated with a decrease in apoptosis. Bcl-2 downregulation and spontaneous apoptosis of T lymphocytes from HIV-infected individuals can be partially prevented by the exogeneous addition of IL-2, but not of IL-12, IL-4, or antibodies that prevent the CD95/CD95 ligand pathway of apoptosis.

Anti-HIV Agents↗

Transmission of human herpesvirus 8 infection from renal-transplant donors to recipients.

BACKGROUND: Human herpesvirus 8 (HHV-8) has been detected in all forms of Kaposi's sarcoma, including transplantation-associated Kaposi's sarcoma. To investigate the possibility of transmission of HHV-8 through allografts, we measured the seroprevalence of HHV-8 before and after renal transplantation. METHODS: Using an enzyme-linked immunosorbent assay with the recombinant HHV-8 protein orf 65.2, we analyzed serum samples from 220 renal-transplant recipients for the presence of antibodies to HHV-8 on the day of transplantation and one year later. Positive results were confirmed by an indirect immunofluorescence assay that detects antibodies to latent antigen and by Western blotting. Follow-up lasted at least four years. RESULTS: The seroprevalence of HHV-8 in graft recipients increased from 6.4 percent on the day of transplantation to 17.7 percent one year after transplantation. Seroconversion occurred within the first year after transplantation in 25 patients, and Kaposi's sarcoma developed in 2 of them within 26 months after transplantation. Sequential serum samples were obtained from 10 of the patients with seroconversion, and in 8 of these patients, IgM antibodies to HHV-8 appeared within three months after transplantation. In the case of six patients who seroconverted, serum samples from the donors were available, and five (83 percent) tested positive for HHV-8. In a control group of eight patients who were seronegative at the time of transplantation and who received allografts from HHV-8-negative donors, none seroconverted within the year after transplantation. CONCLUSIONS: HHV-8 is transmitted through renal allografts and is a risk factor for transplantation-associated Kaposi's sarcoma.

Adolescent↗

High human herpesvirus 8 seroprevalence in the homosexual population in Switzerland.

The seroprevalence of human herpesvirus 8 (HHV-8) in the Swiss population was investigated. By enzyme-linked immunosorbent assay, sera reactive to the recombinant HHV-8 antigen orf 65.2 were found in 24% of human immunodeficiency virus (HIV)-positive patients without and in 92% of HIV-positive patients with Kaposi's sarcoma. Surprisingly, 20% of homosexual HIV-negative men, versus only 7% of heterosexual HIV-negative individuals and 5% of blood donors, had antibodies to HHV-8.

AIDS-Related Opportunistic Infections↗