Lung mucosal immunity to NTHi vaccine antigens: Antibodies in sputum of chronic obstructive pulmonary disease patients

Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory illness in older adults. A major cause of COPD-related morbidity and mortality is acute exacerbation of COPD (AECOPD). Bacteria in the lungs play a role in exacerbation development, and the most common pathogen is non-typeable Haemophilus influenzae (NTHi). A vaccine to prevent AECOPD containing NTHi surface antigens was tested in a clinical trial. This study measured IgG and IgA against NTHi vaccine antigens in sputum. Sputum samples from 40 COPD patients vaccinated with the NTHi vaccine were collected at baseline and 30 days after the second dose. IgG and IgA antibodies against the target antigens and albumin were analyzed in the sputum. We compared antibody signals before and after vaccination, analyzed correlation with disease severity and between sputum and serum samples, and assessed transudation. Antigen-specific IgG were absent before vaccination and present with high titers after vaccination. Antigen-specific IgA before and after vaccination were low but significantly different for two antigens. IgG correlated between sputum and serum, and between sputum and disease severity. Sputum albumin was higher in patients with severe COPD than in those with moderate COPD, suggesting changes in transudation played a role. We demonstrated that immunization with the NTHi vaccine induces antigen-specific antibodies in sputum. The correlation between IgG from sputum and serum and the presence of albumin in the sputum of severe COPD patients suggested transudation of antibodies from the serum to the lungs, although local IgG production could not be excluded.Clinical Trial Registration: NCT02075541.

Putative correlates of protection against shigellosis assessing immunomarkers across responses to S. sonnei investigational vaccine

Shigella spp. are a leading bacterial cause of diarrhea. No widely licensed vaccines are available and there is no generally accepted correlate of protection. We tested a S. sonnei Generalized Modules for Membrane Antigen (GMMA)-based vaccine (1790GAHB) in a phase 2b, placebo-controlled, randomized, controlled human infection model study (NCT03527173) enrolling healthy United States adults aged 18-50 years. We report analyses evaluating immune responses to vaccination, with the aim to identify correlates of risk for shigellosis among assessed immunomarkers. We found that 1790GAHB elicited S. sonnei lipopolysaccharide specific α4β7+ immunoglobulin (Ig) G and IgA secreting B cells which are likely homing to the gut, indicating the ability to induce a mucosal in addition to a systemic response, despite parenteral delivery. We were unable to establish or confirm threshold levels that predict vaccine efficacy facilitating the evaluation of vaccine candidates. However, serum anti-lipopolysaccharide IgG and bactericidal activity were identified as potential correlates of risk for shigellosis.

Application of Transthoracic Echocardiography for Cardiac Safety Evaluation in the Clinical Development Process of Vaccines Against Streptococcus pyogenes

Superficial infections with Streptococcus pyogenes (Strep A), pharyngitis and impetigo can induce acute rheumatic fever, an autoimmune sequela manifesting mostly with arthritis and rheumatic carditis. Valvular heart damage can persist or advance following repeated episodes of acute rheumatic fever, causing rheumatic heart disease. Acute rheumatic fever and rheumatic heart disease disproportionately affect children and young adults in developing countries and disadvantaged communities in developed countries. People living with rheumatic heart disease are at risk of experiencing potentially fatal complications such as heart failure, bacterial endocarditis or stroke. Transthoracic echocardiography plays a central role in diagnosing both rheumatic carditis and rheumatic heart disease. Despite the obvious medical need, no licensed Strep A vaccines are currently available, as their clinical development process faces several challenges, including concerns for cardiac safety. However, the development of Strep A vaccines has been recently relaunched by many vaccine developers. In this context, a reliable and consistent safety evaluation of Strep A vaccine candidates, including the use of transthoracic echocardiography for detecting cardiac adverse events, could greatly contribute to developing a safe and efficacious product in the near future. Here, we propose a framework for the consistent use of transthoracic echocardiography to proactively detect cardiac safety events in clinical trials of Strep A vaccine candidates.

Prevalence and antimicrobial resistance of food safety related Vibrio species in inland saline water shrimp culture farms

This study evaluated the potential pathogenicity and antimicrobial resistance (AMR) of Vibrio species isolated from inland saline shrimp culture farms. Out of 200 Vibrio isolates obtained from 166 shrimp/water samples, 105 isolates were identified as V. parahaemolyticus and 31 isolates were identified as V. alginolyticus and V. cholerae, respectively. During PCR screening of virulence-associated genes, the presence of the tlh gene was confirmed in 70 and 19 isolates of V. parahaemolyticus and V. alginolyticus, respectively. Besides, 10 isolates of V. parahaemolyticus were also found positive for trh gene. During antibiotic susceptibility testing (AST), very high resistance to cefotaxime (93.0%), amoxiclav (90.3%), ampicillin (88.2%), and ceftazidime (73.7%) was observed in all Vibrio species. Multiple antibiotic resistance (MAR) index values of Vibrio isolates ranged from 0.00 to 0.75, with 90.1% of isolates showing resistance to ≥ 3 antibiotics. The AST and MAR patterns did not significantly vary sample-wise or Vibrio species-wise. During the minimum inhibitory concentration (MIC) testing of various antibiotics against Vibrio isolates, the highest MIC values were recorded for amoxiclav followed by kanamycin. These results indicated that multi-drug resistant Vibrio species could act as the reservoirs of antibiotic resistance genes in the shrimp culture environment. The limited host range of 12 previously isolated V. parahaemolyticus phages against V. parahaemolyticus isolates from this study indicated that multiple strains of V. parahaemolyticus were prevalent in inland saline shrimp culture farms. The findings of the current study emphasize that routine monitoring of emerging aquaculture areas is critical for AMR pathogen risk assessment.

Airway pathogens detected in stable and exacerbated COPD in patients in Asia-Pacific

Background

The burden of chronic obstructive pulmonary disease (COPD) in the Asia-Pacific region is projected to increase. Data from other regions show bacterial and viral infections can trigger acute exacerbations of COPD (AECOPD).

Methods

This 1-year prospective epidemiological study (ClinicalTrials.gov identifier: NCT03151395) of patients with moderate to very severe COPD in Hong Kong, the Philippines, South Korea and Taiwan assessed the prevalence in sputum samples (by culture and PCR) of bacterial and viral pathogens during stable COPD and AECOPD. The odds of experiencing an exacerbation was evaluated for pathogen presence, acquisition and apparition. Health-related quality of life (HRQOL) was assessed.

Results

197 patients provided 983 sputum samples, with 226 provided during exacerbation episodes. The mean yearly AECOPD incidence rate was 1.27 per patient. The most prevalent bacteria by PCR at exacerbation were Haemophilus influenzae (Hi) and Moraxella catarrhalis (Mcat); Mcat prevalence was higher at exacerbation than at stable state. Virus prevalence was low, other than for human rhinovirus (HRV) (8.1%, stable state; 16.6%, exacerbation). The odds ratio (95% CI) for an exacerbation (versus stable state) was statistically significant for the presence, acquisition and apparition of Hi (2.20, 1.26–3.89; 2.43, 1.11–5.35; 2.32, 1.20–4.46, respectively), Mcat (2.24, 1.30–3.88; 5.47, 2.16–13.86; 3.45, 1.71–6.98, respectively) and HRV (2.12, 1.15–3.91; 2.22, 1.09–4.54; 2.09, 1.11–3.91, respectively). HRQOL deteriorated according to the number of exacerbations experienced.

Conclusion

In patients with COPD in the Asia-Pacific region, the presence of Hi, Mcat or HRV in sputum samples significantly increased the odds of an exacerbation, providing further evidence of potential roles in triggering AECOPD.

The presence of Haemophilus influenzae, Moraxella catarrhalis or human rhinovirus in sputum samples significantly increases the odds of an exacerbation, as opposed to being in stable state, in COPDhttps://bit.ly/39vI3XU

Safety and immunogenicity of three doses of non-typeable Haemophilus influenzae-Moraxella catarrhalis (NTHi-Mcat) vaccine when administered according to two different schedules: a phase 2, randomised, observer-blind study

Background

Non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) infections are frequently associated with exacerbations of chronic obstructive pulmonary disease (COPD). Results were reported with a two-dose (0–2 months) schedule of an investigational AS01_E-adjuvanted NTHi-Mcat vaccine containing three surface proteins from NTHi and one from Mcat. We evaluated the safety and immunogenicity of three NTHi-Mcat vaccine doses administered in two different schedules to adults with a smoking history (≥ 10 pack-years), immunologically representing the COPD population.

Methods

In this 18-month, randomised (1:1), observer-blind study with 6-month open follow-up, 200 healthy adults aged 40–80 years received NTHi-Mcat vaccine at 0–2–6 months and placebo at 12 months (0–2–6 group), or vaccine at 0–2–12 months and placebo at 6 months (0–2–12 group). Solicited and unsolicited adverse events (AEs) were recorded for 7 and 30 days, respectively, post-vaccination, and potential immune-mediated diseases (pIMDs) and serious AEs (SAEs) throughout the study. Immune responses were assessed.

Results

No safety concerns were identified with the third vaccine dose or overall. Most solicited AEs were mild/moderate. Unsolicited AEs were reported in 16%, 16.1% and 14.4% of participants in the 0–2–6 group post-dose 1, 2 and 3, respectively, and 20%, 20.4% and 9.7%, respectively, in the 0–2–12 group. In 24 months, SAEs were reported in 12 participants in the 0–2–6 group and 9 in the 0–2–12 group (18 events in each group). There were three deaths (unknown cause, 0–2–6 group; myocardial infarction, lung cancer in 0–2–12 group). pIMDs were reported in three participants in the 0–2–6 group (non-serious inflammatory bowel disease, gout, psoriasis) and three in the 0–2–12 group (serious ulcerative colitis, two with non-serious gout). The SAEs, deaths and pIMDs were considered not causally related to vaccination. Antigen-specific antibody concentrations were higher at 12 months post-dose 1 with the 0–2–6 schedule than with the 0–2–12 schedule and at 12 months post-dose 3 were similar between schedules, remaining higher than baseline.

Conclusions

No safety concerns were identified when the investigational NTHi-Mcat vaccine was administered via a 0–2–6 months or 0–2–12 months schedule to older adults with a smoking history. Persistent immune responses were observed after the third vaccine dose.

Trial registrationhttps://clinicaltrials.gov/; NCT03443427, registered February 23, 2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02019-4.

Perception of Employees Regarding the Quality Management System Implemented at a Tertiary Care Eye Hospital in North India: A Mixed-Methods Study

Background:

Quality management in healthcare is critical for hospitals and everyone in the loop —from physicians to support staff—needs to be aware of and involved in this process.

Objectives:

To assess the perception of employees about the quality management system (QMS) implemented at a tertiary care eye hospital in north India and to use it to identify scope for further improvement.

Methods:

This cross-sectional mixed-method study involved both questionnaire-based survey and an in-depth interview by a third party. The questionnaire had 12 questions to assess the changes in culture, infrastructure, environment, system, operation theatre and outpatient department. Employees shared their opinion about improvements brought by the QMS in eight years. Respondents were divided into five groups based on their job description: (i) doctors, (ii) technical staff (nursing/operation theatre/laboratory), (iii) optometrists/opticians/audiologists, (iv) patient care executives and (v) human resources/administration/others.

Results:

Of the 73 employees interviewed, 94.5% perceived an improved treatment and care process and 91.8% perceived improved treatment results. According to 83.6% of the employees, they were encouraged to report patient safety concerns and 71.2% saw improved incidence and adverse event management. The QMS has increased patient satisfaction according to 83%, while 91.8% felt it improved the profile of the hospital. The employees stated no negative effects of the QMS except a long waiting time of the patients and the duplication of paperwork.

Conclusion:

QMS has brought many positive changes across the hospital. Still, there is scope to reduce the patient waiting time and paperwork duplication.

Real-time PCR has advantages over culture-based methods in identifying major airway bacterial pathogens in chronic obstructive pulmonary disease: Results from three clinical studies in Europe and North America

Introduction

We compared the performance of real-time PCR with culture-based methods for identifying bacteria in sputum samples from patients with chronic obstructive pulmonary disease (COPD) in three studies.

Methods

This was an exploratory analysis of sputum samples collected during an observational study of 127 patients (AERIS; NCT01360398), phase 2 study of 145 patients (NTHI-004; NCT02075541), and phase 2b study of 606 patients (NTHI-MCAT-002; NCT03281876). Bacteria were identified by culture-based microbiological methods in local laboratories using fresh samples or by real-time PCR in a central laboratory using frozen samples. Haemophilus influenzae positivity with culture was differentiated from H. haemolyticus positivity by microarray analysis or PCR. The feasibility of bacterial detection by culture-based methods on previously frozen samples was also examined in the NTHI-004 study.

Results

Bacterial detection results from both culture-based and PCR assays were available from 2,293 samples from AERIS, 974 from the NTHI-004 study, and 1736 from the NTHI-MCAT-002 study. Quantitative real-time PCR (qPCR) showed higher positivity rates than culture for H. influenzae (percentages for each study: 43.4% versus 26.2%, 47.1% versus 23.6%, 32.7% versus 10.4%) and Moraxella catarrhalis (12.9% versus 6.3%, 19.0% versus 6.0%, 15.5% versus 4.1%). In the NTHI-004 and NTHI-MCAT-002 studies, positivity rates were higher with qPCR for Streptococcus pneumoniae (15.6% versus 6.1%, 15.5% versus 3.8%); in AERIS, a lower rate with qPCR than with culture (11.0% versus 17.4%) was explained by misidentification of S. pseudopneumoniae/mitis isolates via conventional microbiological methods. Concordance analysis showed lowest overall agreement for H. influenzae (82.0%, 75.6%, 77.6%), due mainly to culture-negative/qPCR-positive samples, indicating lower sensitivity of the culture-based methods. The lowest positive agreement (culture-positive/qPCR-positive samples) was observed for S. pneumoniae (35.1%, 71.2%, 71.2%). Bacterial load values for each species showed a proportion of culture-negative samples with a load detected by qPCR; for some samples, the loads were in line with those observed in culture-positive samples. In the NTHI-004 study, of fresh samples that tested culture-positive, less than 50% remained culture-positive when tested from freeze/thawed samples. In the NTHI-004 study, of fresh samples that tested culture-positive, less than 50% remained culture-positive when tested from freeze/thawed samples.

Discussion

Real-time PCR on frozen sputum samples has enhanced sensitivity and specificity over culture-based methods, supporting its use for the identification of common respiratory bacterial species in patients with COPD.

Long-term immunogenicity and safety of a non-typeable Haemophilus influenzae-Moraxella catarrhalis vaccine: 4-year follow-up of a phase 1 multicentre trial

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Older adults with smoking history received two doses of combined NTHi-Mcat vaccine.

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We evaluated antibody persistence during 4 years of follow-up after vaccination.

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Immune responses against the NTHi protein antigens persisted up to 4 years.

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There was no persistent immune response against the Mcat antigen.

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No safety concerns were identified during the long-term follow-up period.

A multicomponent vaccine has been developed to reduce the frequency of acute exacerbations of COPD associated with non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) infections, containing NTHi (PD and PE-PilA) and Mcat (UspA2) surface proteins. In a randomised, observer-blind, placebo-controlled study with two steps (NCT02547974), the investigational vaccine had good immunogenicity and no safety concerns were identified. In step 2, 90 adults aged 50–71 years with smoking history received two doses 60 days apart of one of two AS01_E-adjuvanted formulations containing 10 µg of each antigen (10–10-AS01) or 10 µg NTHi antigens and 3.3 µg UspA2 (10–3-AS01), or placebo. Long-term persistence of antigen-specific humoral antibodies was assessed in 81 participants during 3 years of follow-up after the initial 14-month study (NCT03201211).

Antigen-specific antibody concentrations were measured in blood samples taken every 6 months. Safety monitoring evaluated serious adverse events (SAEs) and potential immune-mediated disease (pIMD).

Immune responses against NTHi antigens persisted up to 4 years post-vaccination. For PD, PE and PilA, at each follow-up time point, adjusted antibody geometric mean concentrations (GMCs) were higher (non-overlapping 95% confidence intervals [CIs]) in the vaccine groups versus placebo and versus pre-vaccination. Antibody GMC point estimates were higher with 10–3-AS01 than with 10–10-AS01. For UspA2, 95% CIs included 1 for GMC ratios of 10–10-AS01 or 10–3-AS01 to placebo at each time point. During follow-up, SAEs were reported in nine (11.1%) participants, one of which was fatal (lung cancer, 607 days after second 10–10-AS01 dose). One non-serious pIMD, trigeminal neuralgia, was reported 771 days after second 10–3-AS01 dose. The SAEs and pIMD were considered not related to vaccination.

Immune responses against NTHi antigens persisted for 4 years after two-dose vaccination with the investigational NTHi-Mcat vaccine. There was no persistent response against the Mcat antigen. No safety concerns were identified during the long-term follow-up.

Antibiotic sensitivity patterns in Staphylococcus spp. isolated from goat milk in association with molecular detection of antibiotic resistance genes

Background

Microbes become unresponsive to the drugs used to treat infections due to their ability to acquire antimicrobial resistance.

Aims

The present research aimed to study the patterns of phenotypic and genotypic antimicrobial resistance in Staphylococcus spp. isolated from goat milk.

Methods

A total of 200 milk samples were collected to isolate Staphylococcus spp. from mastitic and healthy goats from Punjab state, India. The isolates were then identified biochemically and molecularly (polymerase chain reaction (PCR)). An antibiotic sensitivity test was conducted using 15 different antibiotics. Molecular detection of antibiotic resistance genes was done using PCR. Chi-square test was done to study the association between genotypic and phenotypic resistance patterns among the isolates.

Results

A total of 47 Staphylococcus spp. were isolated of which 33 and 14 isolates were respectively coagulase positive and negative. The isolates phenotypically showed the highest resistance to Penicillin G (P) (91.4%). Methicillin resistant Staphylococcus aureus (MRSA) was found 56.25%. Amongst the antibiotic resistance genes, tetK (87.23%) was the most prevalent isolated gene followed by blaZ (85.10%), mecA (48.93%), and tetM (14.89%). Statistical analysis revealed that the genotypic and phenotypic resistance patterns were significantly associated with penicillin and methicillin (MET) resistances.

Conclusion

The high prevalence of antibiotic-resistant Staphylococcus spp., especially MRSA, in goat milk is of concern and needs to be addressed in this area.

Sputum sample positivity for Haemophilus influenzae or Moraxella catarrhalis in acute exacerbations of chronic obstructive pulmonary disease: evaluation of association with positivity at earlier stable disease timepoints

Background

Infection with Haemophilus influenzae (Hi) or Moraxella catarrhalis (Mcat) is a risk factor for exacerbation in chronic obstructive pulmonary disease (COPD). The ability to predict Hi- or Mcat-associated exacerbations may be useful for interventions developed to reduce exacerbation frequency.

Methods

In a COPD observational study, sputum samples were collected at monthly stable-state visits and at exacerbation during two years of follow-up. Bacterial species (Hi, Mcat) were identified by culture and quantitative PCR assay. Post-hoc analyses were conducted to assess: (1) first Hi- or Mcat-positive exacerbations given presence or absence of Hi or Mcat at the screening visit (stable-state timepoint); (2) first Hi- or Mcat-positive exacerbations given presence or absence of Hi or Mcat at stable timepoints within previous 90 days; (3) second Hi- or Mcat-positive exacerbations given presence or absence of Hi or Mcat at stable timepoints within previous 90 days. Percentages and risk ratios (RRs) with 95% confidence intervals were calculated.

Results

PCR results for analyses 1, 2 and 3 (samples from 84, 88 and 83 subjects, respectively) showed that the risk of an Hi- or Mcat-positive exacerbation is significantly higher if sputum sample was Hi- or Mcat-positive than if Hi- or Mcat-negative at previous stable timepoints (apart from Mcat in analysis 3); RRs ranged from 2.1 to 3.2 for Hi and 1.9 to 2.6 for Mcat.For all analyses, the percentage of Hi- or Mcat-positive exacerbations given previous Hi- or Mcat-positive stable timepoints was higher than the percentage of Hi- or Mcat-positive exacerbations if Hi- or Mcat-negative at previous stable timepoints. Percentage of Hi- or Mcat-positive exacerbations given previous Hi- or Mcat-negative stable timepoints was 26.3%–37.0% for Hi and 17.6%–19.7% for Mcat.

Conclusions

Presence of Hi or Mcat at a stable timepoint was associated with a higher risk of a subsequent Hi- or Mcat-associated exacerbation compared with earlier absence. However, a large percentage of Hi- or Mcat-associated exacerbations was not associated with Hi/Mcat detection at an earlier timepoint. This suggests that administration of an intervention to reduce these exacerbations should be independent of bacterial presence at baseline.

Trial Registrationhttps://clinicaltrials.gov/; NCT01360398, registered May 25, 2011

Staphylococcus aureus Skin and Soft Tissue Infection Recurrence Rates in Outpatients: A Retrospective Database Study at 3 US Medical Centers

Background

Staphylococcusaureus skin and soft tissue infections (SA-SSTIs) are common in healthcare and community settings, and recurrences occur at variable frequency, even after successful initial treatment. Knowing the exact burden and timing of recurrent disease is critical to planning and evaluating interventions to prevent recurrent SSTIs.

Methods

In this retrospective study, SSTI cases in patients aged ≥18 years at 3 US medical centers (Columbia, Chicago, Vanderbilt) between 2006 and 2016 were analyzed according to a biennial cohort design. Index SSTIs (with or without key comorbidities), either microbiologically confirmed to be SA-SSTI or not microbiologically tested (NMT-SSTI), were recorded within 1 calendar year and followed up for 12 months for recurrent infections. The number of index cases, proportion of index cases with ≥1 recurrence(s), time to first recurrence, and number of recurrences were collected for both SA-SSTI and NMT-SSTI events.

Results

In the most recent cohorts, 4755 SSTI cases were reported at Columbia, 2873 at Chicago, and 6433 at Vanderbilt. Of these, 452, 153, and 354 cases were confirmed to be due to S. aureus. Most cases were reported in patients without key comorbidities. Across centers, 16.4%–19.0% (SA-SSTI) and 11.0%–19.2% (NMT-SSTI) of index cases had ≥1 recurrence(s). In patients without key comorbidities, more than 60% of index SSTIs with recurrences had only 1 recurrence, half of which occurred in the first 3 months following primary infection.

Conclusions

SA-SSTI recurrences are common among healthy adults and occur in at least 1 in 6 individuals during the 1 year following the primary event.

Subclinical endometritis in estrual buffaloes: diagnosis, prevalence and impact on reproductive performance

The study evaluated the reliability of polymorphonuclear (PMN) cell count in endometrial cytology by cytobrush technique as a diagnostic for subclinical endometritis (SCE) at the time of estrus and its relationship with bacterial presence and fertility in buffaloes. Healthy pluriparous buffaloes (n = 115) were subjected to endometrial sampling by cytobrush technique (for cytology and bacterial isolation) and ultrasonography of genitalia prior to insemination at the time of spontaneous estrus. Buffaloes were inseminated at the same estrus and were confirmed for pregnancy by ultrasonography at day 40 post-insemination. Growth of aerobic bacteria was recorded in 26.1% (30/115) of estrual buffaloes. Bacteria of eight distinct genera (Staphylococcus spp., Bacillus spp., Proteus spp., Escherichia coli, Klebsiella spp., Streptococcus spp., Pseudomonas spp. and T. pyogenes) were isolated. Presence of bacterial infection was considered as the standard, against which PMN threshold for SCE was calculated by receiver operator curve (ROC). The PMN count of ≥ 5% with good sensitivity (66.7, 95% CI 50.9-81.4) and specificity (87.0%, 95% CI 78.0-94.6) with an overall high diagnostic accuracy (81.7%) for predicting SCE was obtained. Based on calculated PMN threshold, buffaloes were divided into subclinical endometritic (SCE; ≥ 5% PMNs) and control (< 5% PMNs) groups. Thirty-one buffaloes (27.0%, 31/115) had ≥ 5% PMNs in the endometrial cytology at estrus. Ultrasonographic evaluation showed that size of largest follicle, endometrial thickness, and uterine horn diameter did not differ significantly (P > 0.05) between the two groups. Significantly, lower conception rate (22.58 vs 36.90%, P < 0.05) for first artificial inseminations (AIs) and significantly higher number of AIs per pregnancy (2.81 ± 0.27 vs 1.75 ± 0.15, P < 0.05) were recorded in SCE compared to control group. The results indicated that cytobrush based endometrial cytology with 5% PMN cut-off value has a good accuracy for predicting subclinical endometritis at estrus in buffaloes.

Shortening intradermal rabies post-exposure prophylaxis regimens to 1 week: Results from a phase III clinical trial in children, adolescents and adults

Background

This phase III clinical trial compared the immunogenicity and safety of a purified chick-embryo cell rabies vaccine (PCECV) administered according to a shortened post-exposure prophylaxis (PEP) 4-site/1-week intradermal regimen, compared with the currently recommended 2-site/Thai Red Cross (TRC) regimen.

Methodology/Principal findings

This controlled, open-label, multi-center study (NCT02177032) enrolled healthy individuals ≥1 year of age, randomized into 4 groups to receive intradermal PCECV according to one of the 2 regimens, with or without human rabies immunoglobulin (HRIG) administration at first visit (in adults only). Rabies virus neutralizing antibody (RVNA) concentrations and percentages of participants with RVNA concentrations ≥0.5 IU/mL (considered as adequate concentrations following PEP) were assessed up to day (D) 365 post-first vaccination. Non-inferiority of the 4-site/1-week regimen to the 2-site/TRC regimen was demonstrated if at D49, the lower limit of the 95% confidence interval (CI) for the difference between groups in the percentage of participants with adequate RVNA concentrations was >-5%. Of the 443 participants receiving the 4-site/1-week regimen, 88 adults received HRIG; 442 participants received the 2-site/TRC regimen (88 with HRIG). All participants achieved adequate RVNA concentrations by D14. At D49, the difference in percentage of participants with adequate RVNA concentrations between the 4-site/1-week and the 2-site/TRC groups was -1 (95%CI: -2.4–0.0); thus, non-inferiority was concluded. RVNA geometric mean concentrations were 18 IU/mL in 4-site/1-week groups and 12 IU/mL in 2-site/TRC groups at D14, and subsequently declined in all groups. RVNA concentrations were consistently lower in adults with HRIG administration than in those without. The 2 regimens had similar safety profiles. Of the 15 serious adverse events reported in 4-site/1-week groups and 19 in 2-site/TRC groups, none were vaccination-related.

Significance

The data suggest that the 4-site/1-week regimen might be an alternative to current recommendations, with potential benefits in terms of improved cost-efficiency and compliance to vaccination.

Rabies is a deadly, but vaccine-preventable disease which still causes tens of thousands of deaths yearly, mostly in Asia and Africa. Rabies virus is spread via the saliva of infected mammals to humans, usually through bites or contamination of open wounds. Access to measures like wound cleansing with soap and rabies vaccination immediately after contact with a suspected rabid animal (exposure) can be life-saving. The post-exposure vaccination schedule currently recommended by the World Health Organization for intradermal injection is the Thai Red Cross regimen, requiring 4 clinic visits in one month, with 2 injections given at each visit on days (D) 0 (day of the contact), 3, 7, and 28. In this study, we evaluated the antibody responses and the safety profile of a new shortened schedule, requiring 3 clinic visits and only 1 week to complete, consisting of 4 intradermal injections given at each visit on D0, 3, and 7 (the 4-site/1-week regimen). The study was conducted in the Philippines and Thailand which enrolled 885 healthy volunteers, at least 1 year of age, with no real exposure to rabies. The two schedules induced adequate antibody responses in similar proportion of volunteers at day 49. The vaccine administration according to both schedules was well tolerated.

Safety and immunogenicity of a meningococcal B recombinant vaccine when administered with routine vaccines to healthy infants in Taiwan: A phase 3, open-label, randomized study

Neisseria meningitidis is associated with high mortality and morbidity in infants and children worldwide. This phase 3 study (NCT02173704) evaluated safety and immunogenicity of a 4-component serogroup B recombinant meningococcal vaccine (4CMenB) co-administered with routine vaccines in Taiwanese infants. In total, 225 healthy infants were randomized (2 : 1 ) to receive 4CMenB and routine vaccines (4CMenB+Routine) or routine vaccines only (Routine group) at 2, 4, 6 and 12 months of age. Routine vaccines were diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b, 13-valent pneumococcal, hepatitis B, measles-mumps-rubella and varicella vaccines. Immune responses to 4CMenB components (factor H binding protein [fHbp], Neisserial adhesin A [NadA], porin A [PorA] and Neisseria heparin-binding antigen [NHBA]) were evaluated at 1 month post-primary and post-booster vaccination, using human serum bactericidal assay (hSBA). Reactogenicity and safety were also assessed. A sufficient immune response was demonstrated for fHbp, NadA and PorA, at 1 month post-primary and booster vaccination. In the 4CMenB+Routine group, hSBA titers ≥5 were observed in all infants for fHbp and NadA, in 79% and 59% of infants for PorA and NHBA, respectively, at 1 month post-primary vaccination and in 92-99% of infants for all antigens, at 1 month post-booster vaccination. In the 4CMenB+Routine group, hSBA geometric mean titers for all antigens increased post-primary (8.41-963) and post-booster vaccination (17-2315) compared to baseline (1.01-1.36). Immunogenicity of 4CMenB was not impacted by co-administration with routine pediatric vaccines in infants. Reactogenicity was slightly higher in the 4CMenB+Routine group compared with Routine group, but no safety concerns were identified.

MF59-adjuvanted influenza vaccine (FLUAD®) elicits higher immune responses than a non-adjuvanted influenza vaccine (Fluzone®): A randomized, multicenter, Phase III pediatric trial in Mexico

The poor immune response elicited by trivalent influenza vaccines (TIVs) in children can be enhanced by the addition of adjuvants. This observer-blind, randomized Phase III trial assessed the immunogenicity and safety of the MF59-adjuvanted trivalent influenza vaccine FLUAD® (aTIV) and a non-adjuvanted TIV, in healthy children (aged 6 to <72 months) from 3 centers in Mexico, during the 2014-2015 season. The primary objectives were to assess the non-inferiority of aTIV to TIV, measured by geometric mean titers (GMTs), and the safety of aTIV and TIV. Seroconversion was one of several secondary objectives. In total, 287 children were enrolled. The non-inferiority criteria for GMTs and seroconversion were met for aTIV for all 3 vaccine strains. Lower bounds of the 95% confidence intervals for all 3 aTIV:TIV vaccine ratios were >2, showing that the immunogenicity of aTIV was superior to that of TIV for all 3 strains. Solicited adverse events (AEs) were experienced more frequently with aTIV than TIV by younger children (aged 6 to <36 months), but were more frequent with TIV than aTIV in older children (aged 36 to <72 months) who had been vaccinated previously. More unsolicited AEs were associated with aTIV than the TIV. All AEs were of mild or moderate severity. No deaths, serious AEs, or AEs leading to premature withdrawal were reported. Overall, aTIV was highly immunogenic and was well tolerated in healthy children 6 to <72 months of age. These results indicate that aTIV may be a beneficial addition to national pediatric vaccination programs.

Phase 4, Post-Marketing Safety Surveillance of the MF59-Adjuvanted Influenza Vaccines FLUAD® and VANTAFLU® in South Korean Subjects Aged ≥65 Years

Backgroud

Influenza vaccination is recommended for adults aged ≥65 years as they are at high risk of significant morbidity and mortality. This open-label, multicenter, post-marketing surveillance study assessed the safety of the MF59-adjuvanted trivalent inactivated subunit influenza vaccine, which is marketed as FLUAD^® and VANTAFLU^®, in South Korean subjects aged ≥65 years.

Materials and Methods

Solicited local and systemic adverse events (AEs) were collected from day 1 to 4 of the study. All unsolicited AEs and serious AEs (SAEs) were recorded from day 1 until study termination (day 29).

Results

Of the 770 subjects enrolled (FLUAD^®, n = 389; VANTAFLU^®, n = 381), 39% overall experienced any solicited AE. Local AEs were reported by 33% of subjects overall; with the most common events being injection-site pain (30%) and tenderness (27%). Systemic AEs were reported by 19% of subjects overall with the most common events being myalgia (11%) and fatigue (8%).

Conclusion

These results show that the MF59-adjuvanted influenza vaccine known as FLUAD^® or VANTAFLU^® had acceptable safety profiles in older adults (aged ≥65 years) in South Korea.

Comparison of the immunogenicity and safety of the purified chick embryo cell rabies vaccine manufactured in India and Germany: A randomized, single blind, multicentre, phase IV clinical study

This phase IV, single blind study assessed the immunogenicity and safety of India-manufactured purified chick embryo cell rabies vaccine (PCECV), compared with a German-manufactured batch obtained by the same production process. A total of 340 participants enrolled at 2 study sites in India were randomized (1:1:1:1) in 4 groups to receive a 5-dose Essen regimen with either 1 of the 3 Indian batches (PCECV-I) or the German batch (PCECV-G), administered on Days (D) 0, 3, 7, 14 and 30. The lot-to-lot consistency of PCECV-I batches in terms of induced immune response at D14 was demonstrated. The immune response elicited by PCECV-I was shown to be non-inferior to that induced by PCECV-G, as the lower limit of the 95% confidence interval for the ratio (PCECV-I/PCECV-G) of rabies virus neutralising antibody (RVNA) geometric mean concentrations was higher than 0.5 at D14. At least 96% of participants developed adequate RVNA concentrations (≥ 0.5 IU/mL) by D14 and all achieved RVNA concentrations ≥ 0.5 IU/mL by D90. RVNA levels were comparable across all groups throughout the entire study. Solicited local and general symptoms had a similar incidence in all groups. Unsolicited adverse events (AEs) were reported by 11% of participants. Only 1 serious AE (leg fracture) was reported and was not related to vaccination. No deaths and no rabies cases were recorded during the 90 days of observation. The study showed that the 3 PCECV-I and the PCECV-G batches induced a similar immune response and had a comparable safety profile when administered according to a 5-dose schedule.

Immunogenicity and safety of cell-derived MF59®-adjuvanted A/H1N1 influenza vaccine for children

Mass immunization of children has the potential to decrease infection rates and prevent the transmission of influenza. We evaluated the immunogenicity, safety, and tolerability of different formulations of cell-derived MF59-adjuvanted and nonadjuvanted A/H1N1 influenza vaccine in children and adolescents. This was a randomized, single-blind, multicenter study with a total of 666 healthy subjects aged 6 months-17 y in one of 3 vaccination groups, each receiving formulations containing different amounts of influenza A/H1N1 antigen with or without MF59. A booster trivalent seasonal MF59 vaccine was administered one year after primary vaccinations. Antibody titers were assessed by hemagglutination inhibition (HI) and microneutralization assays obtained on days 1, 22, 43, 366, and 387 (3 weeks post booster). Safety was monitored throughout the study. One vaccination with 3.75 μg of A/H1N1 antigen formulated with 50% MF59 (3.75_halfMF59) or 7.5 μg of A/H1N1 antigen formulated with 100% MF59 (7.5_fullMF59) induced an HI titer ≥1:40 in >70% of children in the 1-<3, 3-8, and 9-17 y cohorts; however, 2 vaccinations with nonadjuvanted 15 μg A/H1N1 antigen were needed to achieve this response in the 1-<3 and 3-8 y cohorts. Among children aged 6-11 months, 1 dose of 7.5_fullMF59 resulted in an HI titer ≥1:40 in >70% while 2 doses of 3.75_halfMF59 were required to achieve this result. All vaccines were well tolerated. Our findings support the immunogenicity and safety of the 3.75_halfMF59 (2 doses for children <12 months) and 7.5_fullMF59 vaccine formulations for use in children and adolescents aged 6 months to 17 y The use of the 3.75_halfMF59 could have the benefit of antigen and adjuvant sparing, increasing the available vaccine doses allowing vaccination of more people.

Comparative study on the immunogenicity and safety of a purified chick embryo cell rabies vaccine (PCECV) administered according to two different simulated post exposure intramuscular regimens (Zagreb versus Essen)

Despite availability of effective rabies vaccines, India has the highest global mortality rate for rabies. Low socio-economic communities are most affected due to lack of awareness of the disease and poor compliance to post-exposure prophylactic regimens. Currently, the only approved intramuscular regimen for post-exposure prophylaxis (PEP) against rabies in India is the Essen regimen, which consists of 5 injections administered over 5 separate days in a period of one month. The high number of doses and clinical visits, however, are major reasons for non-compliance, and thus a shorter regimen would be beneficial. In a simulated PEP trial in healthy, adult subjects, this study evaluated whether purified chick embryo cell vaccine (PCECV), administered according to the WHO-recommended 4-dose/3 visit Zagreb vaccination regimen is of equal immunogenicity and safety as the standard Essen regimen in Indian subjects. Two hundred and 50 healthy adults were enrolled and randomized into a Zagreb or Essen group, each receiving PCECV according to their respective regimen. Blood samples were collected on Days 0, 7, 14 and 42 and analyzed using the rapid fluorescent focus inhibition test (RFFIT). By Day 14, all subjects across both groups attained rabies virus neutralizing antibody (RVNA) concentrations of ≥ 0.5IU/ml. The Zagreb regimen was then demonstrated to be immunologically non-inferior to the Essen regimen by Day 14, which was the primary endpoint of the study. No safety issues were noted and the occurrence of adverse events was similar in both groups (17% and 15%, respectively). NCT01365494. CTRI No.: CTRI/2011/07/001857.

Draft Genome Sequences of Two Brucella abortus Strains Isolated from Cattle and Pig

We report the draft genome sequences of two Brucella abortus strains LMN1 and LMN2 isolated from cattle and pig. The LMN1 and LMN2 have the genome size of 3,395,952 bp and 3,334,792 bp, respectively. In addition to the conserved genes of Brucella, few novel regions showing similarity to the phages were identified in both strains.

Safety and immunogenicity of meningococcal ACWY CRM197-conjugate vaccine in children, adolescents and adults in Russia

Neisseria meningitidis is the leading cause of bacterial invasive infections in people aged <15 years in the Russian Federation. The aim of this phase III, multicenter, open-label study was to assess the immunogenicity and safety of the quadrivalent meningococcal CRM197-conjugate vaccine MenACWY when administered to healthy Russian subjects aged 2 years and above. A total of 197 subjects were immunized with a single dose of the vaccine, and serogroup-specific serum bactericidal activity was measured pre and 1-month post-vaccination with human complement (hSBA) serum titers. Regardless of baseline serostatus, 1 month after a single dose of MenACWY-CRM197 85% (95%CI, 79-90%) of subjects showed serologic response against serogroup A, 74% (67-80%) against serogroup C, 60% (53-67%) against serogroup W, and 83% (77-88%) against serogroup Y. The percentage of subjects with hSBA titers ≥ 1:8 1 month after vaccination was 89% (83-93%) against serogroup A, 84% (78-89%) against serogroup C, 97% (93-99%) against serogroup W, and 88% (82-92%) against serogroup Y. Comparable results were obtained across all subjects: children (2 to 10 years), adolescents (11 to 17 years), and adults (≥18 years). The MenACWY-CRM197 vaccine showed an acceptable safety profile and was well tolerated across all age groups, with no serious adverse events or deaths reported during the study. In conclusion, a single dose of meningococcal MenACWY-CRM197 vaccine is immunogenic and has an acceptable safety profile, provides a broad protection against the most frequent epidemic serogroups, and is a suitable alternative to currently available unconjugated monovalent or bivalent polysaccharide vaccines in Russia.

A dose-ranging study of MF59(®)-adjuvanted and non-adjuvanted A/H1N1 pandemic influenza vaccine in young to middle-aged and older adult populations to assess safety, immunogenicity, and antibody persistence one year after vaccination

BACKGROUND

During development of an A/H1N1 pandemic influenza vaccine, this study was performed to identify the antigen and adjuvant content which would provide optimal antibody response and persistence in adults and the elderly. Dose-sparing strategies, such as inclusion of adjuvants, are critical in ensuring the widest possible population coverage in the event of an influenza pandemic, despite a limited global capacity for vaccine manufacture.

METHODS

Healthy subjects aged 18-64 years (n = 1240) and ≥65 years (n = 1352) were vaccinated with 1 of 8 investigational vaccine formulations varying in antigen quantity (3.75 µg to 30 µg of hemagglutinin) and MF59(®) adjuvant (none, half dose, or full dose). All subjects received 2 vaccine doses administered 3 weeks apart. Antibody response was assessed by hemagglutination inhibition assay 1 and 3 weeks after administration of first and second doses. Antibody persistence was assessed after 6 and 12 mo. Vaccine safety was monitored over 12 mo.

RESULTS

All 8 investigational A/H1N1 vaccine formulations were well tolerated, and rapidly induced high antibody titers which met all of the Center for Biologics Evaluation and Research (CBER) and Committee for Medicinal Products for Human Use (CHMP) licensure criteria 3 weeks after one dose. The highest antibody titers were observed in participants vaccinated with higher quantities of antigen and adjuvant.

CONCLUSION

A single vaccine dose containing 3.75 µg of A/California/7/2009 (H1N1) antigen with MF59 adjuvant was identified as optimal for young to middle-aged (18-64 years) and older (≥65 years) adult populations.

Immunogenicity and safety of concomitant administration of a combined hepatitis A/B vaccine and a quadrivalent meningococcal conjugate vaccine in healthy adults

BACKGROUND

This phase 3b randomized, open-label study evaluated the immunogenicity and safety of coadministration of a hepatitis A and/or B vaccine with a quadrivalent oligosaccharide meningococcal CRM197 -conjugate vaccine (MenACWY-CRM), in the context of an accelerated hepatitis A and/or B immunization schedule.

METHODS

A total of 252 healthy adult subjects were randomized to three groups to receive hepatitis A/B only (HepA/B), hepatitis A/B coadministered with MenACWY-CRM (HepA/B+MenACWY-CRM), or MenACWY-CRM only (MenACWY-CRM). Hepatitis A and/or B vaccination was administered in the form of a single booster dose or a primary three-dose series, depending on the hepatitis A and/or B vaccination history of subjects. Antibody responses to hepatitis A/B vaccination were assessed 1 month following the last hepatitis A and/or B dose. Serum bactericidal activity with human complement (hSBA) against meningococcal serogroups A, C, W-135, and Y was assessed 1 month post-MenACWY-CRM vaccination. Safety was monitored throughout the study.

RESULTS

At 1 month following the final hepatitis A and/or B vaccination, concomitant administration of hepatitis A/B and MenACWY-CRM was non-inferior to administration of hepatitis A/B alone in terms of geometric mean concentrations of antibodies against the hepatitis A and B antigens. One month post-MenACWY-CRM vaccination, the percentages of subjects achieving hSBA titers ≥8 for serogroups A, C, W-135, and Y in the HepA/B+MenACWY-CRM group (76, 87, 99, and 94%, respectively) were comparable to those in the MenACWY-CRM group (67, 82, 96, and 88%, respectively). The percentages of subjects reporting adverse events (AEs) were similar across study groups and a majority of the reported AEs were mild to moderate in nature. There were no study vaccine-related serious AEs.

CONCLUSIONS

MenACWY-CRM can be administered concomitantly with a hepatitis A and/or B vaccine in the context of an accelerated hepatitis A and/or B immunization schedule without increasing safety concerns or compromising the immune responses to any of the vaccine antigens. [NCT01453348].

Lepromatous leprosy: An Unusual Presentation

A 25 year old man presented with loss of sensations over both hands and feet and extreme difficulty in passing urine. On examination, an indurated sclerotic plaque was present on shaft of penis and scrotum in addition to other features of lepromatous leprosy. Skin biopsy from the penile lesion showed presence of a large number of acid fast bacilli with a BI of 6+ extending into the epidermis and histopathology showed absence of Grenz zone and presence of foamy macrophages in the dermis up to the dermo-epidermal junction.

Immunogenicity and safety of a single dose of a CRM-conjugated meningococcal ACWY vaccine in children and adolescents aged 2-18 years in Taiwan: results of an open label study

BACKGROUND

MenACWY-CRM (Menveo®, Novartis Vaccines, Siena, Italy) is a quadrivalent meningococcal conjugate vaccine developed to help prevent invasive meningococcal disease caused by Neisseria meningitidis serogroups A, C, W, and Y. It is approved within the European Union in persons >2 years of age and in persons from 2 months to 55 years of age in the United States, among other countries. Little is known about the immunogenicity and safety of this vaccine in Taiwanese children >2 years and adolescents. This study assessed the immunogenicity and safety of a single injection of MenACWY-CRM vaccine in Taiwanese subjects aged 2-18 years old.

METHODS

In this phase III, multicentre, open-label study 341 subjects received one dose of MenACWY-CRM. Immunogenicity measures were rates of seroresponse (defined as the proportion of subjects with a postvaccination hSBA ≥1:8 if the prevaccination (baseline) titre was <1:4, or at least a fourfold higher hSBA titre than baseline if the prevaccination titre was ≥1:4), percentages of subjects with serum bactericidal activity (hSBA) ≥1:8 for serogroups A, C, W and Y and hSBA geometric mean titres (GMTs). Local and systemic reactions and all adverse events (AEs) were recorded for 7 days, and medically attended AEs for 1 month post-vaccination.

RESULTS

Seroresponse rates after MenACWY-CRM vaccination at Day 29 for the serogroups A, C, W, and Y were 83%, 93%, 50%, and 65%, respectively. At Day 29 the percentages of subjects with hSBA ≥1:8 against all four serogroups A, C, W and Y were: 83%, 96%, 96% and 82%, respectively. GMTs against all serogroups rose by ≥7-fold from baseline to Day 29. The vaccine was well tolerated.

CONCLUSIONS

A single dose of MenACWY-CRM demonstrated a robust immune response, and an acceptable safety profile in Taiwanese children and adolescents.

Comparison of the safety and immunogenicity of an MF59®-adjuvanted with a non-adjuvanted seasonal influenza vaccine in elderly subjects

AIM

Adjuvanted influenza vaccines can overcome the poor antibody response of conventional non-adjuvanted vaccines in the elderly. We evaluated the immunogenicity, safety and clinical effectiveness of an MF59(®)-adjuvanted trivalent influenza vaccine (aTIV) compared with a non-adjuvanted vaccine (TIV) in subjects ≥65 years old, with or without co-morbidities.

METHODS

In 2010-2011, subjects (N=7082) were randomized to receive one dose of aTIV or TIV. Co-primary objectives were to assess lot-to-lot consistency of aTIV, non-inferiority, superiority and immunogenicity 22 days after vaccination. Clinical effectiveness, reactogenicity and serious adverse events were monitored up to Day 366.

RESULTS

The immunological equivalence of three lots of aTIV was demonstrated. aTIV was not only non-inferior to TIV but also elicited significantly higher antibody responses at Day 22 than TIV against all homologous and heterologous strains, even in subjects with co-morbidities. Superiority was not established. Reactogenicity was higher in the aTIV group, but reactions were mild to moderate and transient.

CONCLUSIONS

aTIV elicited a significantly higher antibody response than TIV, especially against A/H3N2 strains, although superiority by pre-defined criteria was not formally met. The study demonstrates potential immunological benefits of MF59-adjuvanted influenza vaccines for the elderly. This trial was registered with www.clinicaltrials.gov (NCT01162122).

Co-administration of a meningococcal glycoconjugate ACWY vaccine with travel vaccines: a randomized, open-label, multi-center study

BACKGROUND

Potential interactions between vaccines may compromise the immunogenicity and/or safety of individual vaccines so must be assessed before concomitant administration is recommended. In this study, the immunogenicity and safety of travel vaccines against Japanese encephalitis (JEV) and rabies (PCECV) administered together with or without a quadrivalent meningococcal glycoconjugate ACWY-CRM vaccine were evaluated (NCT01466387).

METHOD

Healthy adults aged 18 to ≤60 years were randomized to one of four vaccine regimens: JEV + PCECV + MenACWY-CRM, JEV + PCECV, PCECV or MenACWY-CRM. Immunogenicity at baseline and 28 days post-complete vaccination was assessed by serum bactericidal assay using human complement or neutralization tests. Adverse events (AEs) were collected throughout the study period.

RESULTS

JEV + PCECV + MenACWY-CRM was non-inferior to JEV + PCECV. Post-vaccination seroprotective neutralizing titers or concentrations were achieved in 98-99% (JE) and 100% (rabies) of subjects across the vaccine groups. Antibody responses to vaccine meningococcal serogroups were in the same range for MenACWY-CRM and JEV + PCECV + MenACWY-CRM. Rates of reporting of AEs were similar for JEV + PCECV and JEV + PCECV + MenACWY-CRM.

CONCLUSIONS

MenACWY-CRM was administered with an inactivated adjuvanted JE and a purified chick embryo cell-culture rabies vaccine without compromising immunogenicity or safety of the individual vaccines. These data provide evidence that MenACWY-CRM could be effectively incorporated into travel vaccination programs.

TRIAL NUMBER

NCT01466387.

Composition and temperature-induced structural changes in lead-tellurite glasses on different length scales

Processes occurring at macroscopic and microscopic length scales across the glass transition (T(g)) in lead-tellurite glass (PbO)(x)(TeO(2))(1-x) (x = 0.1-0.3) are investigated using Brillouin and Raman spectroscopy, respectively. For all the samples, the temperature dependence of the longitudinal acoustic (LA) mode is found to exhibit a universal scaling below T(g) and a rapid softening above T(g). The lower value of elastic modulus at a higher concentration of network modifier PbO, estimated from Brillouin data, arises due to loss of network rigidity. From quantitative analysis of the reduced Raman spectra, several modes are found to exhibit anomalous changes across T(g). Instead of the expected anharmonic behaviour, several modes exhibit hardening, suggesting stiffening of the stretching force constants with temperature, the effect being more pronounced in glasses with higher x. In addition, incorporation of PbO in the glass is also found to narrow down the bond-length distribution, as evident from the sharpening of the Raman bands. The stiffening of the force constants of molecular units at a microscopic length scale and the decrease of elastic constant attributed to loss of network rigidity on a macroscopic length scale appear to be opposite. These different behaviours at two length scales are understood on the basis of a microscopic model involving TeO(n) and PbO units in the structure.

Quenchable high-density amorphous polymorphs of zirconium tungstate

Zirconium tungstate turns amorphous above 2 GPa. Amorphous-Zr(WO(4))(2) is studied in situ using synchrotron x-ray diffraction and Raman spectroscopy at high pressure. The height and the position of the first peak of the structure factor as a function of pressure exhibit discontinuous changes suggesting an amorphous to amorphous transformation around 19 GPa. The pressure dependence of the Raman mode frequencies of the tungstate tetrahedra also exhibits a change at the same pressure. The high-density amorphous form appears to have higher oxygen coordination as compared to the low-density amorphous form.

Profile of menopausal women in rural north India

OBJECTIVE

To ascertain the profile of menopausal women in rural north India. Setting Six villages were selected in a rural field practice area of Department of Community Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh, north India.

METHODS

A female social worker obtained relevant data in the study area during 1999-2001. This involved individual interviews of women aged 35-55 years through a house-to-house survey.

RESULTS

Of the 558 enlisted women, 152 (27.2%) had attained menopause. Average age at menopause was 44.1 years. More than half (53%) reported seven or more symptoms at menopause. Diminished vision was reported as the most common symptom at menopause. The majority (85%) admitted that menopause adversely affected women's physical health. However, most of them (95%) considered menopause socially good for women and welcomed it. None of our respondents reported use of hormone replacement therapy.

CONCLUSION

Women in rural north India viewed menopause positively. Medication of menopause was minimal.

Confined acoustic phonon in CdSC(1-x)Se(x) nanoparticles in borosilicate glass

We calculate low-frequency Raman scattering from the confined acoustic phonon modes of CdS(1-x)Se(x) nanoparticles embedded in borosilicate glass. The calculation of the Raman scattering by acoustic phonons in nanoparticles has been performed by using third-order perturbation theory. The deformation potential approximation is used to describe the electron-phonon interaction. The Raman-Brillouin electronic density and the electron-phonon interaction are found to increases with decreasing size of nanoparticle. A good agreement between the calculated and reported low-frequency Raman spectra is found.

Phonon confinement in stressed silicon nanocluster

Confined acoustic and optical phonons in Si nanoclusters embedded in sapphire, synthesized using ion-beam implantation are investigated using Raman spectroscopy. The l=0 and l=2 confined acoustic phonons, found at low Raman shift, are analyzed using complex frequency model and the size of the nanoparticles are estimated as 4 and 6 nm. For the confined optical phonon, in contrast to expected red shift, the Raman line shape shows a substantial blue shift, which is attributed to size dependent compressive stress in the nanoparticles. The calculated Raman line shape for the stressed nanoparticles fits well to data. The sizes of Si nanoparticles obtained using complex frequency model are consistent with the size estimated from the fitting of confined optical phonon line shapes and those found from X-ray diffraction and TEM.

Studies of local structure at Zr sites in pressure amorphized zirconium tungstate

Amorphous to crystalline transition in pressure quenched Zr(0.5)Hf(0.5)W(2)O(8) has been studied with respect to local structures of ZrO(6) using the perturbed angular correlation technique. In an untreated crystalline sample close to 0.7 fraction of the probe atoms occupy Zr sites of regular ZrO(6) while the remaining three fractions are understood to be associated with contracted and distorted octahedra. The existence of six distinct ZrO(6) could be deduced based on perturbed angular correlation studies in the pressure amorphized sample. In the amorphous sample these ZrO(6) are associated with appreciable octahedral distortions. Isochronal annealing measurements show that these octahedra remain structurally quite stable up to 800 K. Values of quadrupole frequencies tend to become close to those experienced by probe atoms in a crystalline sample for annealing at 870 K, implying that around this temperature there is an onset of amorphous to crystalline transition. Complete restoration of quadrupole parameters to those of the untreated crystalline sample is seen subsequent to annealing at 975 K.

Spectroscopic characterization of nanocrystalline chromium nitride (CrN)

Nanocrystalline chromiuim nitride has been synthesised by direct gas phase nitridation of nanocrystalline chromia at 1100 degrees C in ammonia-atmosphere. XRD of this material showed formation of single phase CrN with particle size around 20 nm. AFM studies showed particle distribution along with some soft agglomerated nanostructures. Nanocrystalline Cr2O3 and partially-as well as fully--converted nanocrystalline CrN were also investigated using various spectroscopic techniques like XPS, FT-IR, and Raman for gaining insight into the conversion pathways. Spectroscopic investigations of these materials clearly indicate that complete conversion of CrN occurs by nitriding at 1100 degrees C for 4 hrs. The salient spectroscopic features of these nanocrystalline materials with respect to their microcrystalline counterparts are discussed.

Decreasing strabismus surgery

AIM

To determine whether there has been a consistent change across countries and healthcare systems in the frequency of strabismus surgery in children over the past decade.

METHODS

Retrospective analysis of data on all strabismus surgery performed in NHS hospitals in England and Wales, on children aged 0-16 years between 1989 and 2000, and between 1994 and 2000 in Ontario (Canada) hospitals. These were compared with published data for Scotland, 1989-2000.

RESULTS

Between 1989 and 1999-2000 the number of strabismus procedures performed on children, 0-16 years, in England decreased by 41.2% from 15 083 to 8869. Combined medial rectus recession with lateral rectus resection decreased from 5538 to 3013 (45.6%) in the same period. Bimedial recessions increased from 489 to 762, oblique tenotomies from 43 to 121, and the use of adjustable sutures from 29 to 44, in 2000. In Ontario, operations for squint decreased from 2280 to 1685 (26.1%) among 0-16 year olds between 1994 and 2000.

CONCLUSION

The clinical impression of decrease in the frequency of paediatric strabismus surgery is confirmed. In the authors' opinion this cannot be fully explained by a decrease in births or by the method of healthcare funding. Two factors that might have contributed are better conservative strabismus management and increased subspecialisation that has improved the quality of surgery and the need for re-operation. This finding has a significant impact upon surgical services and also on the training of ophthalmologists.

Raman scattering investigations of nanocrystalline thorium oxide

Raman scattering investigations are carried out on nanocrystalline thorium oxide powders. Shift and broadening of the Raman peak associated with F2g phonons are observed for the nanocrystalline samples as compared with those of the bulk. The peak shift and broadening are found to increase further as the particle size decreases. A quantitative analysis of the Raman line shape is carried out with a Gaussian confinement model, and the estimated size is found to be consistent with that obtained from X-ray diffraction and transmission electron microscopy.

Ion-acoustic compressive and rarefactive double layers in a warm multicomponent plasma with negative ions

Propagation of ion-acoustic double layers has been studied in plasma consisting of warm positive- and negative-ion species with different masses, concentrations, and charge states along with electrons with two-electron temperature distributions. It is found that there exist two critical concentrations of negative ions, alpha(R) and alpha(Q). One of them (alpha(R)) generally decides the existence of the double layer, whereas the other one (alpha(Q)) decides the nature of the double layer. It is found that the system supports ion-acoustic double layers only when the negative-ion concentration (alpha) is greater than the critical concentration alpha(R). It is also found that below the critical concentration alpha(Q), compressive double layers exist and above it rarefactive double layers exist. For some values of cold-electron concentrations (mu) it is found that if the temperature of the negative-ion species is higher than the positive-ion species, then the system supports compressive double layers for all values of alpha lying in the range 0<alpha<alpha(Q). The dependence of the critical concentrations on the temperatures of the two-ion species and on the concentration of cold electrons has also been investigated.