Increased risk of hospitalization for acute lower respiratory tract infection among Australian Indigenous infants 5-23 months of age following pneumococcal vaccination : a cohort study

Background Australian Indigenous children are the only population worldwide to receive the 7-valent pneumococcal conjugate vaccine (7vPCV) at 2, 4, and 6 months of age and the 23-valent pneumococcal polysaccharide vaccine (23vPPV) at 18 months of age. We evaluated this program's effectiveness in reducing the risk of hospitalization for acute lower respiratory tract infection (ALRI) in Northern Territory (NT) Indigenous children aged 5-23 months. Methods We conducted a retrospective cohort study involving all NT Indigenous children born from 1 April 2000 through 31 October 2004. Person-time at-risk after 0, 1, 2, and 3 doses of 7vPCV and after 0 and 1 dose of 23vPPV and the number of ALRI following each dose were used to calculate dose-specific rates of ALRI for children 5-23 months of age. Rates were compared using Cox proportional hazards models, with the number of doses of each vaccine serving as time-dependent covariates. Results There were 5482 children and 8315 child-years at risk, with 2174 episodes of ALRI requiring hospitalization (overall incidence, 261 episodes per 1000 child-years at risk). Elevated risk of ALRI requiring hospitalization was observed after each dose of the 7vPCV vaccine, compared with that for children who received no doses, and an even greater elevation in risk was observed after each dose of the 23vPPV ( adjusted hazard ratio [HR] vs no dose, 1.39; 95% confidence interval [CI], 1.12-1.71;). Risk was highest among children Pp. 002 vaccinated with the 23vPPV who had received < 3 doses of the 7vPCV (adjusted HR, 1.81; 95% CI, 1.32-2.48). Conclusions Our results suggest an increased risk of ALRI requiring hospitalization after pneumococcal vaccination, particularly after receipt of the 23vPPV booster. The use of the 23vPPV booster should be reevaluated.

Rates of radiologically confirmed pneumonia as defined by the World Health Organization in Northern Territory Indigenous children

Objective To determine the burden of hospitalised, radiologically confirmed pneumonia (World Health Organization protocol) in Northern Territory Indigenous children. Design, setting and participants Historical, observational study of all hospital admissions for any diagnosis of NT resident Indigenous children, aged between >= 29 days and < 5 years, 1 April 1997 to 31 March 2005. Intervention All chest radiographs taken during these admissions, regardless of diagnosis, were assessed for pneumonia in accordance with the WHO protocol. Main outcome measure The primary outcome was endpoint consolidation (dense fluffy consolidation [alveolar infiltrate] of a portion of a lobe or the entire lung) present on a chest radiograph within 3 days of hospitalisation. Results We analysed data on 24 115 hospitalised episodes of care for 9492 children and 13 683 chest radiographs. The average annual cumulative incidence of endpoint consolidation was 26.6 per 1000 population per year (95% Cl, 25.3-27.9); 57.5 per 1000 per year in infants aged 1-11 months, 38.3 per 1000 per year in those aged 12-23 months, and 13.3 per 1000 per year in those aged 24-59 months. In all age groups, rates of endpoint consolidation in children in the arid southern region of NT were about twice that of children in the tropical northern region. Conclusion The rates of severe pneumonia in hospitalised NT Indigenous children are among the highest reported in the world. Reducing this unacceptable burden of disease should be a national health priority.

Hospitalisation of Indigenous children in the Northern Territory for lower respiratory illness in the first year of life

Objective To describe the epidemiology of acute lower respiratory infection (ALRI) and bronchiectasis in Northern Territory Indigenous infants hospitalised in the first year of life. Design A historical cohort study constructed from the NT Hospital Discharge Dataset and the NT Imm(u)nisation Register. Participants and setting All NT resident Indigenous infants, born 1 January 1999 to 31 December 2004, admitted to NT public hospitals and followed up to 12 months of age. Main outcome measures Incidence of ALRI and bronchiectasis (ICD-10-AM codes) and radiologically confirmed pneumonia (World Health Organization protocol). Results Data on 9295 infants, 8498 child-years of observation and 15 948 hospitalised episodes of care were analysed. ALRI incidence was 426.7 episodes per 1000 child-years (95% Cl, 416.2-437.2). Incidence rates were two times higher (relative risk, 2.12; 95% Cl, 1.98-2.27) for infants in Central Australia compared with those in the Top End. The median age at first admission for an ALRI was 4.6 months (interquartile range, 2.6-7.3). Bronchiolitis accounted for most of the disease burden, with a rate of 227 per 1000 child-years. The incidence of first diagnosis of bronchiectasis was 1.18 per 1000 child-years (95% Cl, 0.60-2.16). One or more key comorbidities were present in 1445 of the 3227 (44.8%) episodes of care for ALRI. Conclusions Rates of ALRI and bronchiectasis in NT Indigenous infants are excessive, with early onset, frequent repeat episodes, and a high prevalence of comorbidities. These high rates of disease demand urgent attention.

Identification of radiological alveolar pneumonia in children with high rates of hospitalized respiratory infections : Comparison of WHO-defined and pediatric pulmonologist diagnosis in the clinical context

Background A reliable standardized diagnosis of pneumonia in children has long been difficult to achieve. Clinical and radiological criteria have been developed by the World Health Organization (WHO), however, their generalizability to different populations is uncertain. We evaluated WHO defined chest radiograph (CXRs) confirmed alveolar pneumonia in the clinical context in Central Australian Aboriginal children, a high risk population, hospitalized with acute lower respiratory illness (ALRI). Methods CXRs in children (aged 1-60 months) hospitalized and treated with intravenous antibiotics for ALRI and enrolled in a randomized controlled trial (RCT) of Vitamin A/Zinc supplementation were matched with data collected during a population-based study of WHO-defined primary endpoint pneumonia (WHO-EPC). These CXRs were reread by a pediatric pulmonologist (PP) and classified as pneumonia-PP when alveolar changes were present. Sensitivities, specificities, positive and negative predictive values (PPV, NPV) for clinical presentations were compared between WHO-EPC and pneumonia-PP. Results Of the 147 episodes of hospitalized ALRI, WHO-EPC was significantly less commonly diagnosed in 40 (27.2%) compared to pneumonia-PP (difference 20.4%, 95% CI 9.6-31.2, P < 0.001). Clinical signs on admission were poor predictors for both pneumonia-PP and WHO-EPC; the sensitivities of clinical signs ranged from a high of 45% for tachypnea to 5% for fever + tachypnea + chest-indrawing. The PPV range was 40-20%, respectively. Higher PPVs were observed against the pediatric pulmonologist's diagnosis compared to WHO-EPC. Conclusions WHO-EPC underestimates alveolar consolidation in a clinical context. Its use in clinical practice or in research designed to inform clinical management in this population should be avoided. Pediatr Pulmonol. 2012; 47:386-392. (C) 2011 Wiley Periodicals, Inc.

Gemcitabine reactivates epigenetically silenced genes and functions as a DNA methyltransferase inhibitor

Gemcitabine is indicated in combination with cisplatin as first-line therapy for solid tumours including non-small cell lung cancer (NSCLC), bladder cancer and mesothelioma. Gemcitabine is an analogue of pyrimidine cytosine and functions as an anti-metabolite. Structurally, however, gemcitabine has similarities to 5-aza-2-deoxycytidine (decitabine/Dacogen®), a DNA methyltransferase inhibitor (DNMTi). NSCLC, mesothelioma and prostate cancer cell lines were treated with decitabine and gemcitabine. Reactivation of epigenetically silenced genes was examined by RT-PCR/qPCR. DNA methyltransferase activity in nuclear extracts and recombinant proteins was measured using a DNA methyltransferase assay, and alterations in DNA methylation status were examined using methylation-specific PCR (MS-PCR) and pyrosequencing. We observe a reactivation of several epigenetically silenced genes including GSTP1, IGFBP3 and RASSF1A. Gemcitabine functionally inhibited DNA methyltransferase activity in both nuclear extracts and recombinant proteins. Gemcitabine dramatically destabilised DNMT1 protein. However, DNA CpG methylation was for the most part unaffected by gemcitabine. In conclusion, gemcitabine both inhibits and destabilises DNA methyltransferases and reactivates epigenetically silenced genes having activity equivalent to decitabine at concentrations significantly lower than those achieved in the treatment of patients with solid tumours. This property may contribute to the anticancer activity of gemcitabine.

Phase III trial comparing paclitaxel poliglumex (CT-2103, PPX) in combination with carboplatin versus standard paclitaxel and carboplatin in the treatment of PS 2 patients with chemotherapy-naïve advanced non-small cell lung cancer

INTRODUCTION: Performance status (PS) 2 patients with non-small cell lung cancer (NSCLC) experience more toxicity, lower response rates, and shorter survival times than healthier patients treated with standard chemotherapy. Paclitaxel poliglumex (PPX), a macromolecule drug conjugate of paclitaxel and polyglutamic acid, reduces systemic exposure to peak concentrations of free paclitaxel and may lead to increased concentrations in tumors due to enhanced vascular permeability. METHODS: Chemotherapy-naive PS 2 patients with advanced NSCLC were randomized to receive carboplatin (area under the curve = 6) and either PPX (210 mg/m/10 min without routine steroid premedication) or paclitaxel (225 mg/m/3 h with standard premedication) every 3 weeks. The primary end point was overall survival. RESULTS: A total of 400 patients were enrolled. Alopecia, arthralgias/myalgias, and cardiac events were significantly less frequent with PPX/carboplatin, whereas grade ≥3 neutropenia and grade 3 neuropathy showed a trend of worsening. There was no significant difference in the incidence of hypersensitivity reactions despite the absence of routine premedication in the PPX arm. Overall survival was similar between treatment arms (hazard ratio, 0.97; log rank p = 0.769). Median and 1-year survival rates were 7.9 months and 31%, for PPX versus 8 months and 31% for paclitaxel. Disease control rates were 64% and 69% for PPX and paclitaxel, respectively. Time to progression was similar: 3.9 months for PPX/carboplatin versus 4.6 months for paclitaxel/carboplatin (p = 0.210). CONCLUSION: PPX/carboplatin failed to provide superior survival compared with paclitaxel/carboplatin in the first-line treatment of PS 2 patients with NSCLC, but the results with respect to progression-free survival and overall survival were comparable and the PPX regimen was more convenient. © 2008International Association for the Study of Lung Cancer.

Small RNA sequencing of potato leafroll virus-infected plants reveals an additional subgenomic RNA encoding a sequence-specific RNA-binding protein

Potato leafroll virus (PLRV) is a positive-strand RNA virus that generates subgenomic RNAs (sgRNA) for expression of 3' proximal genes. Small RNA (sRNA) sequencing and mapping of the PLRV-derived sRNAs revealed coverage of the entire viral genome with the exception of four distinctive gaps. Remarkably, these gaps mapped to areas of PLRV genome with extensive secondary structures, such as the internal ribosome entry site and 5' transcriptional start site of sgRNA1 and sgRNA2. The last gap mapped to ~500. nt from the 3' terminus of PLRV genome and suggested the possible presence of an additional sgRNA for PLRV. Quantitative real-time PCR and northern blot analysis confirmed the expression of sgRNA3 and subsequent analyses placed its 5' transcriptional start site at position 5347 of PLRV genome. A regulatory role is proposed for the PLRV sgRNA3 as it encodes for an RNA-binding protein with specificity to the 5' of PLRV genomic RNA. © 2013.

Rice ragged stunt oryzavirus genome segments S7 and S10 encode non-structural proteins of M(r) 68 025 (Pns7) and M(r) 32364 (Pns10) : brief report

The nucleotide sequences of genome segments S7 and S10 of a Thai-isolate of rice ragged stunt virus (RRSV) were determined. The 1938 bp S7 sequence contains a single large open reading frame (ORF) spanning nucleotides 20 to 1 843 that is predicted to encode a protein of M(r) 68 025. The 1 162 bp S10 sequence has a major ORF spanning nucleotides 142 to 1 032 that is predicted to encode a protein of M(r) 32364. This S10 ORF is preceded by a small ORF (nt 20-55) which is probably a minicistron. Coupled in vitro transcription-translation from the two major ORFs gave protein products of the expected sizes. However, no protein was visualised from S10 when the small ORF sequence was included. Proteins were expressed in Escherichia coli from the full length ORF of S7 (P7) and from a segment of the S10 ORF (P10) fused to the ORF of glutathione S-transferase (GST). Neither fusion protein was recognised by polyclonal antibodies raised against RRSV particles. Furthermore, polyclonal antibodies raised against GST-P7 fusion protein did not recognise any virion structural polypeptides. These data strongly suggest that the proteins P7 and P10 do not form part of RRSV particle. This is further supported by observed sequence homology (though very weak) of predicted.

Development of empirical equations for irradiance profile of a standard parabolic trough collector using Monte Carlo ray tracing technique

Irradiance profile around the receiver tube (RT) of a parabolic trough collector (PTC) is a key effect of optical performance that affects the overall energy performance of the collector. Thermal performance evaluation of the RT relies on the appropriate determination of the irradiance profile. This article explains a technique in which empirical equations were developed to calculate the local irradiance as a function of angular location of the RT of a standard PTC using a vigorously verified Monte Carlo ray tracing model. A large range of test conditions including daily normal insolation, spectral selective coatings and glass envelop conditions were selected from the published data by Dudley et al. [1] for the job. The R2 values of the equations are excellent that vary in between 0.9857 and 0.9999. Therefore, these equations can be used confidently to produce realistic non-uniform boundary heat flux profile around the RT at normal incidence for conjugate heat transfer analyses of the collector. Required values in the equations are daily normal insolation, and the spectral selective properties of the collector components. Since the equations are polynomial functions, data processing software can be employed to calculate the flux profile very easily and quickly. The ultimate goal of this research is to make the concentrating solar power technology cost competitive with conventional energy technology facilitating its ongoing research.

Effect of chemical conjugation of L-leucine to chitosan on the dispersibility and drug release of a dry powder inhaler nanoparticle formulation

Purpose: This study investigated the effect of chemical conjugation of the amino acid L-leucine to the polysaccharide chitosan on the dispersibility and drug release pattern of a polymeric nanoparticle (NP)-based controlled release dry powder inhaler (DPI) formulation. Methods: A chemical conjugate of L-leucine with chitosan was synthesized and characterized by Infrared (IR) Spectroscopy, Nuclear Magnetic Resonance (NMR) Spectroscopy, Elemental Analysis and X-ray Photoelectron Spectroscopy (XPS). Nanoparticles of both chitosan and its conjugate were prepared by a water-in-oil emulsification – glutaraldehyde cross-linking method using the antihypertensive agent, diltiazem (Dz) hydrochloride as the model drug. The surface morphology and particle size distribution of the nanoparticles were determined by Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS). The dispersibility of the nanoparticle formulation was analysed by a Twin Stage Impinger (TSI) with a Rotahaler as the DPI device. Deposition of the particles in the different stages was determined by gravimetry and the amount of drug released was analysed by UV spectrophotometry. The release profile of the drug was studied in phosphate buffered saline at 37 ⁰C and analyzed by UV spectrophotometry. Results: The TSI study revealed that the fine particle fractions (FPF), as determined gravimetrically, for empty and drug-loaded conjugate nanoparticles were significantly higher than for the corresponding chitosan nanoparticles (24±1.2% and 21±0.7% vs 19±1.2% and 15±1.5% respectively; n=3, p<0.05). The FPF of drug-loaded chitosan and conjugate nanoparticles, in terms of the amount of drug determined spectrophotometrically, had similar values (21±0.7% vs 16±1.6%). After an initial burst, both chitosan and conjugate nanoparticles showed controlled release that lasted about 8 to 10 days, but conjugate nanoparticles showed twice as much total drug release compared to chitosan nanoparticles (~50% vs ~25%). Conjugate nanoparticles also showed significantly higher dug loading and entrapment efficiency than chitosan nanoparticles (conjugate: 20±1% & 46±1%, chitosan: 16±1% & 38±1%, n=3, p<0.05). Conclusion: Although L-leucine conjugation to chitosan increased dispersibility of formulated nanoparticles, the FPF values are still far from optimum. The particles showed a high level of initial burst release (chitosan, 16% and conjugate, 31%) that also will need further optimization.

Molecular mechanisms of cisplatin resistance in lung cancer

Cisplatin is one of the most potent anticancer agents, displaying significant clinical activity against a variety of solid tumours. To date, cisplatin-based combination treatment remains the most effective systemic chemotherapy for non-small cell lung cancer (NSCLC) patients. Unfortunately, the outcome of cisplatin therapy in NSCLC has reached a plateau due to the development of both intrinsic and acquired resistance that have become a major obstacle in the use of cisplatin in the clinical setting. The molecular mechanisms that underlie chemoresistance are largely unknown. Mechanisms of acquired resistance to cisplatin include reduced intracellular accumulation of the drug, enhanced drug inactivation by metallothionine and glutathione, increased repair activity of DNA damage, and altered expression of oncogenes and regulatory proteins. Cisplatin-induced cytotoxicity is mediated through the induction of apoptosis and cell cycle arrest as a result of cisplatin-DNA adduct formation, which in turn, activates multiple signaling pathways and mediators. These include p53, Bcl-2 family, caspases, cyclins, CDKs, MAPK and PI3K/Akt. Increased expression of anti-apoptotic genes and mutations in the intrinsic apoptotic pathway may also contribute to the inability of cells to detect DNA damage or to induce apoptosis. This chapter will provide an insight into the mechanisms involved in cisplatin resistance and a better understanding of the molecular basis of the cellular response to cisplatin-based chemotherapy in lung cancer.

Nedd4-2functionally interacts with ClC-5: involvement in constitutive albumin endocytosis in proximal tubule cells

Constitutive albumin uptake by the proximal tubule is achieved by a receptor-mediated process in which the Cl– channel, ClC-5, plays an obligate role. Here we investigated the functional interaction between ClC-5 and ubiquitin ligases Nedd4 and Nedd4-2 and their role in albumin uptake in opossum kidney proximal tubule (OK) cells. In vivo immunoprecipitation using an anti-HECT antibody demonstrated that ClC-5 bound to ubiquitin ligases, whereas glutathione S-transferase pull-downs confirmed that the C terminus of ClC-5 bound both Nedd4 and Nedd4-2. Nedd4-2 alone was able to alter ClC-5 currents in Xenopus oocytes by decreasing cell surface expression of ClC-5. In OK cells, a physiological concentration of albumin (10 μg/ml) rapidly increased cell surface expression of ClC-5, which was also accompanied by the ubiquitination of ClC-5. Albumin uptake was reduced by inhibiting either the lysosome or proteasome. Total levels of Nedd4-2 and proteasome activity also increased rapidly in response to albumin. Overexpression of ligase defective Nedd4-2 or knockdown of endogenous Nedd4-2 with small interfering RNA resulted in significant decreases in albumin uptake. In contrast, pathophysiological concentrations of albumin (100 and 1000 μg/ml) reduced the levels of ClC-5 and Nedd4-2 and the activity of the proteasome to the levels seen in the absence of albumin. These data demonstrate that normal constitutive uptake of albumin by the proximal tubule requires Nedd4-2, which may act via ubiquitination to shunt ClC-5 into the endocytic pathway.

A rapid transcriptional activation is induced by the dormancy-breaking chemical hydrogen cyanamide in kiwifruit (Actinidia deliciosa) buds

Budbreak in kiwifruit (Actinidia deliciosa) can be poor in locations that have warm winters with insufficient winter chilling. Kiwifruit vines are often treated with the dormancy-breaking chemical hydrogen cyanamide (HC) to increase and synchronize budbreak. This treatment also offers a tool to understand the processes involved in budbreak. A genomics approach is presented here to increase our understanding of budbreak in kiwifruit. Most genes identified following HC application appear to be associated with responses to stress, but a number of genes appear to be associated with the reactivation of growth. Three patterns of gene expression were identified: Profile 1, an HC-induced transient activation; Profile 2, an HC-induced transient activation followed by a growth-related activation; and Profile 3, HC- and growth-repressed. One group of genes that was rapidly up-regulated in response to HC was the glutathione S-transferase (GST) class of genes, which have been associated with stress and signalling. Previous budbreak studies, in three other species, also report up-regulated GST expression. Phylogenetic analysis of these GSTs showed that they clustered into two sub-clades, suggesting a strong correlation between their expression and budbreak across species.

Preparation and in vitro evaluation of a polymer based controlled release dry powder inhaler formulation for pulmonary delivery

This thesis described the synthesis of an L-leucine conjugate of the biodegradable polymer, chitosan and its potential application for the development of controlled release nanoparticulate dry powder inhaler (DPI) formulations. The study demonstrated that the physicochemical properties of conjugated chitosan nanoparticles had favourable effects on the dispersibility and controlled release profile of a model drug. The toxicity profile of the nanoparticulate formulation revealed promising outcome for its use in pulmonary delivery. The chitosan conjugate produced in this project would be useful for the application of polymer nanoparticulate systems for efficient lung delivery of drugs.

Sphingolipid distribution changes with age in the human lens

The formation of an internal barrier to the diffusion of small molecules in the lens during middle age is hypothesized to be a key event in the development of age-related nuclear (ARN) cataract. Changes in membrane lipids with age may be responsible. In this study, we investigated the effect of age on the distribution of sphingomyelins, the most abundant lens phospholipids. Human lens sections were initially analyzed by MALDI mass spectrometry imaging. A distinct annular distribution of the dihydrosphingomyelin, DHSM (d18:0/16:0), in the barrier region was observed in 64- and 70-year-old lenses but not in a 23-year-old lens. An increase in the dihydroceramide, DHCer (d18:0/16:0), in the lens nucleus was also observed in the older lenses. These findings were supported by ESI mass spectrometry analysis of lipid extracts from lenses dissected into outer, barrier, and nuclear regions. A subsequent analysis of 18 lenses ages 20-72 years revealed that sphingomyelin levels increased with age in the barrier region until reaching a plateau at approximately 40 years of age. Such changes in lipid composition will have a significant impact on the physical properties of the fiber cell membranes and may be associated with the formation of a barrier.-Deeley, J. M., J. A. Hankin, M. G. Friedrich, R. C. Murphy, R. J. W. Truscott, T. W. Mitchell, and S. J. Blanksby. Sphingolipid distribution changes with age in the human lens. J. Lipid Res. 2010. 51: 2753-2760.