Immunogenicity of a yeast-recombinant hepatitis B vaccine in high-risk children

Horizontal transmission of hepatitis B virus (HBV) from illicit drug users to their contacts, including young children, can be prevented by active immunization against HBV. Yeast-recombinant hepatitis B vaccines are now available for this purpose, but their potential efficacy in such high-risk contacts has not yet been evaluated. Therefore we gave 20 mcg of a recombinant yeast-derived hepatitis B vaccine to 38 children who were at high risk for HBV infection because they had been institutionalized in a community for drug users in which 8.7% of the occupants are carriers. After third dose of vaccine (at 0, 1, and 6 months), all children had anti-HBs responses with titers of 10 mIU/ml or more, with 81% showing responses greater than 1,000 mIU/ml. At 12 months, the percentage of anti-HBs-positive children was 100%, and the percentage of children with anti-HBs higher than 1,000 mIU/ml was 56%. None of the children developed HBV infection during follow-up. Hence the recombinant vaccine was immunogenic, with percentages of seroconversion and anti-HBs titers comparable with those attained in other categories of high-risk children with plasma-derived vaccines.     

Migrainous Vertigo: Results of Caloric Testing and Stabilometric Findings

Background.— Association between migraine and vertigo has been widely studied during the last years. A central or peripheral vestibular damage may occur in patients with migrainous vertigo. Despite much evidence, at present the International Headache Society classification does not include a specific category for migrainous vertigo. Objectives.— To assess the prevalence of central and peripheral vestibular disorders and postural abnormalities in patients diagnosed as affected by definite migrainous vertigo according to Neuhauser. Methods.— Thirty patients with migraine and acute vertigo lasting from minutes to hours underwent a full otoneurological screening for spontaneous, positional, and positioning nystagmus with head‐shaking and head‐thrust (Halmagyi) tests, an audiometric examination, and videonystagmography with bithermal stimulation according to Freyss. Videonystagmographic findings were compared with those of 15 migraineurs without lifetime vertigo (group M). Next day, a static posturography was performed; posturographic results have been compared with those of a second control group of 30 healthy patients matched for age and sex (group C). Results.— In total, 14 subjects with migrainous vertigo showed otovestibular disorders; 6 subjects showed impaired vestibulo‐oculomotor reflexes (20%). Five more patients had bilateral increased responses (16.6%). Five patients showed signs of central brainstem or cerebellar disorders for altered pursuit or saccades or positional direction changing nystagmus. Stabilometric results returned higher values of Length and Surface above all when testing was performed in eyes closed conditions compared with the normal control group. The subgroup of 14 subjects with migrainous vertigo and vestibular abnormalities performed poorly in stabilometric exams and seemed to rely more on visual cues in balance control than the subgroup of 16 subjects with migrainous vertigo but without abnormalities. Discussion.— Our results indicate that vestibular functional damage may occur in all vestibular pathways; central and peripheral signs are equally represented. Our data are not inconsistent with the hypothesis that a vestibulo‐spinal dysfunction is the causal factor for the posturographic results. Moreover, the Visual Romberg Index is significant for increased visual cue dependence in migraineurs.     

IL-3 or IL-7 increases ex vivo gene transfer efficiency in ADA-SCID BM CD34+ cells while maintaining in vivo lymphoid potential.

To improve maintenance and gene transfer of human lymphoid progenitors for clinical use in gene therapy of adenosine deaminase (ADA)-deficient SCID we investigated several gene transfer protocols using various stem cell-enriched sources. The lymphoid differentiation potential was measured by an in vitro clonal assay for B/NK cells and in the in vivo SCID-hu mouse model. Ex vivo culture with the cytokines TPO, FLT3-ligand, and SCF (T/F/S) plus IL-3 or IL-7 substantially increased the yield of transduced bone marrow (BM) CD34(+) cells purified from ADA-SCID patients or healthy donors, compared to T/F/S alone. Moreover, the use of IL-3 or IL-7 significantly improved the maintenance of in vitro B cell progenitors from ADA-SCID BM cells and allowed the efficient transduction of B and NK cell progenitors. Under these optimized conditions transduced CD34(+) cells were efficiently engrafted into SCID-hu mice and gave rise to B and T cell progeny, demonstrating the maintenance of in vivo lymphoid reconstitution capacity. The protocol based on the T/F/S + IL-3 combination was included in a gene therapy clinical trial for ADA-SCID, resulting in long-term engraftment of stem/progenitor cells. Remarkably, gene-corrected BM CD34(+) cells obtained from one patient 4 and 11 months after gene therapy were capable of repopulating the lymphoid compartment of SCID-hu hosts.     

Closed system endotracheal suctioning maintains lung volume during volume-controlled mechanical ventilation

OBJECTIVE: A closed suction system (CS) maintains connection with the mechanical ventilator during tracheal suctioning and is claimed to limit loss in lung volume and oxygenation. We compared changes in lung volume, oxygenation, airway pressure and hemodynamics during endotracheal suctioning performed with CS and with an open suction system (OS). DESIGN: Prospective, randomized study. SETTING: Intensive care unit in a university hospital. PATIENTS: We enrolled ten patients, volume-controlled (VC) ventilated with a Siemens Servo 900 ventilator (PaO2/FIO2 192 +/- 70, PEEP 10.7 +/- 3.9 cmH2O). INTERVENTIONS: We performed four consecutive tracheal suction maneuvers, two with CS and two with OS, at 20-min intervals. During the suction maneuvers continuous suction was applied for 20 s. MEASUREMENTS AND MAIN RESULTS: We measured end-expiratory lung volume changes (delta VL), tidal volume (VTrt), respiratory rate (RR) and minute volume (VErt) by respiratory inductive plethysmography; arterial oxygen saturation (SpO2), airway pressure and arterial pressure (PA). Loss in lung volume during OS (delta VL 1.2 +/- 0.7 l) was significantly higher than during CS (delta VL 0.14 +/- 0.1 l). During OS we observed a marked drop in SpO2, while during CS the change was only minor. During CS ventilation was not interrupted and we observed an immediate increase in RR (due to the activation of the ventilator's trigger), while VTrt decreased, VErt was maintained. CONCLUSIONS: Avoiding suction-related lung volume loss can be helpful in patients with an increased tendency to alveolar collapse; CS allows suctioning while avoiding dramatic drops in lung volumes and seems to be safe during the VC ventilation setting that we used.     

Sustained suppression of hepatitis C virus by high doses of interferon and ribavirin in adult hemophilic patients

BACKGROUND: In a recent randomized controlled study, only a minority (15%) of adult hemophiliacs with chronic HCV achieved a sustained virologic response to treatment with interferon (IFN) and ribavirin given at standard doses. STUDY DESIGN AND METHODS: Whether the therapeutic response might be improved in these patients by increasing the doses of IFN was evaluated. Thirty-four previously untreated, adult hemophiliacs with chronic HCV but negative for HIV were investigated. There were 33 men and 1 woman, aged 21 to 60 years (mean, 36). Twenty-three patients (68%) had genotype 1, and median serum HCV-RNA was 473 x 10(3) IU per L (range, 3.6-2145). Patients were treated with IFN at 5 million units (MU) thrice weekly for 6 months, followed by 3 mol/L for 6 additional months in combination with daily oral doses of 1 or 1.2 g of ribavirin. RESULTS: A total of 33 patients (97%) completed the study; one patient withdrew because of treatment-related symptoms. Treatment dosage had to be reduced in 20 patients (59%). By intention-to-treat analysis, 14 patients (41%) had a sustained virologic response, particularly those infected by HCV genotype 2 or 3 (70% vs. 29% with genotype 1 or 4, p < 0.05). Sustained response rates were similar in the 13 compliant patients and the 20 patients who had to reduce IFN and/or ribavirin doses (54% vs. 35%). CONCLUSIONS: High-dose IFN therapy plus ribavirin provided high rates of sustained virologic responses in adult hemophiliacs with chronic HCV, even if side-effects led to dose reduction in half of these patients.     

Inhaled activated protein C protects mice from ventilator-induced lung injury

Introduction  

Activated Protein C (APC), an endogenous anticoagulant, improves tissue microperfusion and endothelial cell survival in systemic inflammatory states such as sepsis, but intravenous administration may cause severe bleeding. We have thus addressed the role of APC delivered locally by inhalation in preventing acute lung injury from alveolar overdistention and the subsequent ventilator-induced lung injury (VILI). We also assessed the effects of APC on the activation status of Extracellular- Regulated Kinase 1/2 (ERK) pathway, which has been shown to be involved in regulating pulmonary responses to mechanical stretch.     

Lack of rapid virological response predicts interferon-alpha2b/ribavirin therapy failure in HCV genotype 2 patients: a single-centre study

BACKGROUND: A minority of patients with HCV-2 chronic hepatitis does not attain a sustained virological response to interferon-based therapies. Registration trials have failed to identify the real proportion of HCV-2 non-responders, and predictors of non-response. The analysis of 'real-life' HCV-2 patients might help define the effectiveness of anti-HCV therapy and the role of response moderators. METHODS: A re-analysis of all treatment-naive HCV-2 patients who consecutively received weight-dosed ribavirin with either 3 MU three times a week standard interferon-alpha2b or 1.5 microg/kg/week pegylated interferon-alpha2b. RESULTS: The 94 interferon-treated patients and the 136 pegylated-interferon-treated patients were comparable for demography, prevalence of cirrhosis (25%) and adherence to therapy (74%). By intention-to-treat analysis, the overall sustained virological response rate was 80% (82% interferon versus 78% pegylated interferon). Overall, sustained virological rates were 83% for the 182 patients who cleared HCV RNA at week 4 (rapid virological response) and 52% for the 48 who did not (P < 0.001). The corresponding week 12 figures of HCV RNA clearance were 90% and 32%, respectively (P < 0.001). Sustained response was independent of gender, age, body mass index, modality of infection, duration and severity of liver disease, adherence to therapy and interferon type. After stratification for interferon type, the only treatment failure predictor was persistence of HCV RNA at week 4 and 12. CONCLUSIONS: Despite the prevalence of moderators of treatment outcome, HCV-2 patients showed as high sustained virological response rates as those reported in registration trials for HCV-2 and HCV-3 pooled patients; pegylated interferon therapy failure was predicted by lack of rapid virological response.