Association between awareness of vulnerability and disaster preparedness in an infrastructure-resilient city: a population-based study.

OBJECTIVES: Factors associated with an individual's awareness of vulnerability can be modified by the infrastructure of a city. These factors may impact disaster preparedness among local populations in an infrastructure-resilient city, which further influences the health risks of various population subgroups. STUDY DESIGN: This was a population-based study. METHODS: Four population subgroups, which have previously been reported to be related to awareness of vulnerability (i.e. past experiences, sociodemographic deprivation, poor housing conditions and family medical needs), were analysed for their impacts on disaster preparedness. Validated population-based phone interviews (n = 856) were conducted in Hong Kong. Three types of disaster preparedness were studied: (1) physical preparedness; (2) social preparedness; and (3) education preparedness. RESULTS: Previous experience of social hazards, accidental hazards and epidemics increased disaster preparedness among the local population. Specifically, experiences of accidental hazards and social hazards were positively associated with physical preparedness (odds ratios 1.626, 95% confidence interval [95% CI] 1.215, 2.172) and 1.501 [95% CI 1.114, 2.024], respectively). However, experiences of natural hazards did not increase preparedness, even in Hong Kong, which is a city with high 'disaster resilience' because of its well-developed infrastructure. Moreover, individuals with a low educational level or low income had lower education preparedness, unmarried individuals had lower social preparedness, and poor housing conditions of non-private-housing households had negative associations with education preparedness. These findings partially align with local disaster responses to the 2018 Typhoon Mangkhut, the 2019 social unrest and the 2020 COVID-19 pandemic, all of which were observed after the 2018 survey reported in this study. CONCLUSIONS: Social and environmental interventions should be targeted to marginalised subpopulations through location-based community strategies to encourage increased environmental knowledge and participation in disaster preparedness activities.

Evaluation of the first pharmacist-administered vaccinations in Western Australia: a mixed-methods study.

OBJECTIVES: This study evaluated the uptake of Western Australian (WA) pharmacist vaccination services, the profiles of consumers being vaccinated and the facilitators and challenges experienced by pharmacy staff in the preparation, implementation and delivery of services. DESIGN: Mixed-methods methodology with both quantitative and qualitative data through surveys, pharmacy computer records and immuniser pharmacist interviews. SETTING: Community pharmacies in WA that provided pharmacist vaccination services between March and October 2015. PARTICIPANTS: Immuniser pharmacists from 86 pharmacies completed baseline surveys and 78 completed exit surveys; computer records from 57 pharmacies; 25 immuniser pharmacists were interviewed. MAIN OUTCOME MEASURES: Pharmacy and immuniser pharmacist profiles; pharmacist vaccination services provided and consumer profiles who accessed services. RESULTS: 15 621 influenza vaccinations were administered by immuniser pharmacists at 76 WA community pharmacies between March and October 2015. There were no major adverse events, and <1% of consumers experienced minor events which were appropriately managed. Between 12% and 17% of consumers were eligible to receive free influenza vaccinations under the National Immunisation Program but chose to have it at a pharmacy. A high percentage of vaccinations was delivered in rural and regional areas indicating that provision of pharmacist vaccination services facilitated access for rural and remote consumers. Immuniser pharmacists reported feeling confident in providing vaccination services and were of the opinion that services should be expanded to other vaccinations. Pharmacists also reported significant professional satisfaction in providing the service. All participating pharmacies intended to continue providing influenza vaccinations in 2016. CONCLUSIONS: This initial evaluation of WA pharmacist vaccination services showed that vaccine delivery was safe. Convenience and accessibility were important aspects in usage of services. There is scope to expand pharmacist vaccination services to other vaccines and younger children; however, government funding to pharmacists needs to be considered.

ROS1 Kinase Inhibitors for Molecular-Targeted Therapies.

ROS1 is a pivotal transmembrane receptor protein tyrosine kinase which regulates several cellular processes like apoptosis, survival, differentiation, proliferation, cell migration, and transformation. There is increasing evidence supporting that ROS1 plays an important role in different malignancies including glioblastoma, colorectal cancer, gastric adenocarcinoma, inflammatory myofibroblastic tumor, ovarian cancer, angiosarcoma, and non small cell lung cancer; thus, ROS1 has become a potential drug discovery target. ROS1 shares about 49% sequence homology with ALK primary structure; therefore, wide range of ALK kinase inhibitors have shown in vitro inhibitory activity against ROS1 kinase. After Crizotinib approval by FDA for the management of ALK-rearranged lung cancer, ROS1-positive tumors have been focused. Although significant advancements have been achieved in understanding ROS1 function and its signaling pathways plus recent discovery of small molecules modulating ROS1 protein, a vital need of medicinal chemistry efforts is still required to produce selective and potent ROS1 inhibitors as an important therapeutic strategy for different human malignancies. This review focuses on the current knowledge about different scaffolds targeting ROS1 rearrangements, methods to synthesis, and some biological data about the most potent compounds that have delivered various scaffold structures.

Molecular analysis of Plasmodium falciparum co-chaperone Aha1 supports its interaction with and regulation of Hsp90 in the malaria parasite.

The recent recognition of Plasmodium falciparum Hsp90 (PfHsp90) as a promising anti-malaria drug target has sparked interest in identifying factors that regulate its function and drug-interaction. Co-chaperones are well-known regulators of Hsp90's chaperone function, and certain members have been implicated in conferring protection against lethal cellular effects of Hsp90-specific inhibitors. In this context, studies on PfHsp90's co-chaperones are imperative to gain insight into the regulation of the chaperone in the malaria parasite. In this study, a putative co-chaperone P. falciparum Aha1 (PfAha1) was identified and investigated for its interaction and regulation of PfHsp90. A previous genome-wide yeast two-hybrid study failed to identify PfAha1's association with PfHsp90, which prompted us to use a directed assay to investigate their interaction. PfAha1 was shown to interact with PfHsp90 via the in vivo split-ubiquitin assay and the association was confirmed in vitro by GST pull-down experiments. The GST pull-down assay further revealed PfAha1's interaction with PfHsp90 to be dependent on MgCl(2) and ATP, and was competed by co-chaperone Pfp23 that binds PfHsp90 under the same condition. In addition, the PfHsp90-PfAha1 complex was found to be sensitive to disruption by high salt, indicating a polar interaction between them. Using bio-computational modelling coupled with site-directed mutagenesis, the polar residue N108 in PfAha1 was found to be strategically located and essential for PfHsp90 interaction. The functional significance of PfAha1's interaction was clearly that of exerting a stimulatory effect on the ATPase activity of PfHsp90, likely to be essential for promoting the activation of PfHsp90's client proteins.

An update on ABCB1 pharmacogenetics: insights from a 3D model into the location and evolutionary conservation of residues corresponding to SNPs associated with drug pharmacokinetics.

The human ABCB1 protein, (P-glycoprotein or MDR1) is a membrane-bound glycoprotein that harnesses the energy of ATP hydrolysis to drive the unidirectional transport of substrates from the cytoplasm to the extracellular space. As a large range of therapeutic agents are known substrates of ABCB1 protein, its role in the onset of multidrug resistance has been the focus of much research. This role has been of particular interest in the field of pharmacogenomics where genetic variation within the ABCB1 gene, particularly in the form of single nucleotide polymorphisms (SNPs), is believed to contribute to inter-individual variation in ABCB1 function and drug response. In this review we provide an update on the influence of coding region SNPs within the ABCB1 gene on drug pharmacokinetics. By utilizing the crystal structure of the mouse ABCB1 homolog (Abcb1a), which is 87% homologous to the human sequence, we accompany this discussion with a graphical representation of residue location for amino acids corresponding to human ABCB1 coding region SNPs. Also, an assessment of residue conservation, which is calculated following multiple sequence alignment of 11 confirmed sequences of ABCB1 homologs, is presented and discussed. Superimposing a 'heat map' of residue homology to the Abcb1a crystal structure has permitted additional insights into both the conservation of individual residues and the conservation of their immediate surroundings. Such graphical representation of residue location and conservation supplements this update of ABCB1 pharmacogenetics to help clarify the often confounding reports on the influence of ABCB1 polymorphisms on drug pharmacokinetics and response.

Multicenter external validation of the ABCD2 score in triaging TIA patients.

OBJECTIVES: A simple clinical score (ABCD(2) score) has been introduced to triage TIA patients with a high early risk of stroke. External validation studies have yielded inconsistent results regarding the predictive ability of the ABCD(2) score. We aimed to prospectively validate the former score in a multicenter case series study. METHODS: We prospectively calculated the ABCD(2) score (age [> or = 60 years: 1 point]; blood pressure [systolic >140 mm Hg or diastolic >90 mm Hg: 1[; clinical features [unilateral weakness: 2, speech disturbance without weakness: 1, other symptom: 0]; duration of symptoms [ <10 minutes: 0, 10-59 minutes: 1, > or = 60 minutes: 2]; diabetes mellitus [yes: 1]) in consecutive TIA patients hospitalized in 3 tertiary care neurology departments across 2 different racial populations (white and Asian). RESULTS: The 7-day and 90-day risks of stroke in the present case series (n = 148) were 8% (95% CI 4%-12%) and 16% (95% CI 10%-22%). The ABCD(2) score accurately discriminated between TIA patients with high 7-day (c statistic 0.72, 95% CI 0.57-0.88) and 90-day (c statistic 0.75, 95% CI 0.65-0.86) risks of stroke. The 90-day risk of stroke was 7-fold higher in patients with an ABCD(2) score >3 points (28%, 95% CI 18%-38%) than in patients with an ABCD(2) score < or = 3 points (4%, 95% CI 0%-9%). After adjustment for stroke risk factors, race, history of previous TIA, medication use before the index TIA and secondary prevention treatment strategies, an ABCD(2) score of >2 was associated with a nearly 5-fold greater 90-day risk of stroke (hazard ratio 4.65, 95% CI 1.04-20.84, p = 0.045). CONCLUSION: Our findings externally validate the usefulness of the ABCD(2) score in triaging TIA patients with a high risk of early stroke in a multiethnic sample of hospitalized patients. The present data support current guidelines endorsing the immediate hospitalization of patients with an ABCD(2) score >2.

Characterization of Plasmodium falciparum co-chaperone p23: its intrinsic chaperone activity and interaction with Hsp90.

It is well known that the co-chaperone p23 regulates Hsp90 chaperone activity in protein folding. In Plasmodium falciparum, a putative p23 (Pfp23) has been identified through genome analysis, but its authenticity has remained unconfirmed since co-immunoprecipitation experiments failed to show its interaction with P. falciparum Hsp90 (PfHsp90). Thus, recombinant Pfp23 and PfHsp90 proteins purified from expressed clones were used in this study. It was clear that Pfp23 exhibited chaperone activity by virtue of its ability to suppress citrate synthase aggregation at 45 degrees C. Pfp23 was also shown to interact with PfHsp90 and to suppress its ATPase activity. Analyses of modeled Pfp23-PfHsp90 protein complex and site-directed mutagenesis further revealed strategically placed amino acid residues, K91, H93, W94 and K96, in Pfp23 to be crucial for binding PfHsp90. Collectively, this study has provided experimental evidence for the inherent chaperone function of Pfp23 and its interaction with PfHsp90, a sequel widely required for client protein activation.

Plasmodium falciparum pyruvate kinase as a novel target for antimalarial drug-screening.

BACKGROUND: Global travellers are increasingly at risk of contracting malaria. The increasing occurrence of drug-resistance in many endemic areas emphasizes the need for novel drug targets for antimalarial-screening. In this study, the use of pyruvate kinase as a drug-target is evaluated. The functional validation of a gene encoding pyruvate kinase (designated PK1) has previously been reported. However, alternative copies of this enzyme encoded by Plasmodium falciparum could also circumvent the role of PK1. A survey of genome data revealed a putative ORF seemingly coding for another pyruvate kinase (designated PK2). METHODS: The expression of PK1 and PK2 in in vitro cultures were investigated by RT-PCR. Biocomputational analysis was carried out to identify structural differences between the P. falciparum pyruvate kinases and the corresponding enzymes from its human host. RESULTS: Both PK1 and PK2 were indeed actively transcribed during the intraerythrocytic stages, suggesting the involvement of both enzymes during infection. A comparison of amino acid residues at the effector binding sites of PK1 and PK2, to those of the human pyruvate kinases revealed some significant differences that could serve as targets for selective inhibitors to be designed against parasitic pyruvate kinases. CONCLUSION: Experimental evidence for the expression of both PK1 and PK2 during the blood stages of malaria infection was provided. Interestingly, phylogenetic analysis revealed that the "PK2" type of enzyme appears to be confined to Apicomplexans, an important observation with respect to the assessment of PK2 as a drug-target.

Cysteine protease falcipain 1 in Plasmodium falciparum is biochemically distinct from its isozymes.

Falcipains form a class of papain-like cysteine proteases found in Plasmodium falciparum. This group of proteases has been suggested to be promising targets for anti-malarial chemotherapy. Despite being the first falcipain to be identified, the physiological role(s) of falcipain 1 (fp1) remains a mystery. Its suggested functions include haemoglobin degradation, erythrocytic invasion and oocyst production. In this study, the procurement of the gene coding for fp1 and its soluble expression in a heterologous host, Escherichia coli, have enabled further enzyme characterization. The recombinant fp1 protease was found to be unlike falcipain 2 (fp2A) in being more active at neutral pH than at acidic pH against the Z-LR-AMC fluorogenic substrate, suggesting a probable localization in the cytosol and not in the food vacuole. Interestingly, a common cysteine specific inhibitor, E64, did not inhibit fp1 activity, indicating dissimilar biochemical characteristics of fp1 from the other falcipains. This may be explained by computational analysis of the primary structures of the falcipain isozymes, as well as that of papain. The analysis revealed that Tyr61 (papain numbering), which is correspondingly absent in fp1, might be an important residue involved in E64 substrate binding.

Otorhinolaryngeal foreign bodies in children presenting to the emergency department.

INTRODUCTION: Accidents with foreign bodies are common in the paediatric population. It is impossible to mandate that all foreign bodies (FB) in the ear, nose and throat (ENT) of children should be removed by the specialty-trained physicians. This study evaluates the management of ENT FB removal in children achieved by emergency physicians not trained in otolaryngology in an urban tertiary care paediatric emergency department. METHODS: A retrospective study was conducted on consecutive paediatric patients presenting with suspected foreign body in the ear, nose or throat to the children's emergency department (ED) of KK Women's and Children's Hospital over a 10-month period. Removal methods, foreign body types, rates of successful removal and associated complications were evaluated. RESULTS: There were 353 patients, most of whom presented after office hours. An attempt at removal of FB by the emergency physician was made in 76.8 percent of the cases. ENT specialist referral in the ED was made in 1.7 percent of the cases. 50.1 percent of cases were discharged after successful removal of FB in the ED. 4.2 percent of cases were admitted for removal of FB and 44.8 percent of cases were referred to the ENT specialist clinic for further assessment. CONCLUSION: The emergency physician managed most cases in the ED and urgent referral to ENT specialists was not required. Complications and morbidity often occur from repeated attempts at removal of the FB. ENT opinion should be sought whenever there is doubt. The ED physician should be skilled in techniques of FB removal, especially throat FB, which had the lowest rate of success in our study.

A complete library of amino acid alterations at N304 in Streptomyces clavuligerus deacetoxycephalosporin C synthase elucidates the basis for enhanced penicillin analogue conversion.

N304 of Streptomyces clavuligerus deacetoxycephalosporin C synthase was mutagenized to alter its catalytic ability. Given that N304A, N304K, N304L, and N304R mutant enzymes exhibited significant improvements in penicillin analogue conversions, we advocate that replacement of N304 with residues with aliphatic or basic side chains is preferable for engineering of a hypercatalytic enzyme.

Functional characterization of an alternative [lactate dehydrogenase-like] malate dehydrogenase in Plasmodium falciparum.

The catalysis of malate dehydrogenase (MDH) in Plasmodium falciparum (pfMDH) which involves NAD/NADH coupling is crucial for the parasite's pathogenicity. Primers were designed based on the P. falciparum genome resource, and these facilitated the cloning of a gene coding for pfMDH from a local clinical isolate. The DNA sequence of the cloned gene revealed an open-reading frame that encodes a protein of 313 amino acids. After induction in Escherichia coli BL21, enzyme assays of the expressed pfMDH purified by affinity chromatography exhibited significant enzyme activity of about 50 U/mg, where one unit (U) of enzyme activity is defined as the amount of enzyme oxidising 1 microol NADH/min. Based on its phylogenetic status amongst MDHs and lactate dehydrogenases (LDHs), the cloned gene was clearly defined as belonging to the NADH-dependent [LDH-like] MDHs. It is noteworthy that pfMDH harbours unique structural characteristics potentially useful for screening drugs specific for disabling parasitic enzymes.

Survival of Tilletia indica Teliospores in Different Soils.

To determine the potential for Tilletia indica, cause of Karnal bunt of wheat, to survive and become established in new areas, a teliospore longevity study was initiated in Kansas, Maryland, Georgia, and Arizona. Soil from each location was infested with T. indica teliospores and placed in polyester mesh bags. The bags were placed within soil from the same location within polyvinyl chloride pipes. Pipes were buried in the respective plots such that the bags were at 5-, 10-, and 25-cm depths. Each pipe was open at the ends to allow interaction with the outside environment, however fitted with screens preventing possibility of teliospore escape. In the Karnal bunt-quarantine area of Arizona, bags of infested soil also were placed outside the pipes. Teliospore-infested soil from each location was maintained dry in a laboratory. During the first 2 years, viability declined more rapidly in pipes than outside pipes, and more rapidly in fields in Kansas and Maryland than in Georgia or Arizona. After 2 years, viability declined nearly equally. In the laboratory over 3 years, viability decreased significantly more rapidly in dry soil from Kansas or Maryland than in dry soil from Georgia or Arizona, while pure teliospores remained unchanged. We hypothesized that soils, irrespective of weather, affect teliospore longevity.

Thermostable malate synthase of Streptomyces thermovulgaris.

The gene, encoding malate synthase (MS), aceB, was cloned from the thermophilic bacterium Streptomyces thermovulgaris by homology-based PCR. The 1,626-bp cloned fragment encodes a protein consisting of 541 amino acids. S. thermovulgaris malate synthase (stMS) gene was over-expressed in Escherichia coli using a glutathione-S transferase (GST) fusion vector (pGEX-6P-1), purified by affinity chromatography, and subsequently cleaved from its GST fusion partner. The purified stMS was characterized and compared to a mesophilic malate synthase (scMS) from Streptomyces coelicolor. stMS exhibited higher temperature optima (40-60 degrees C) than those of scMS (28-37 degrees C). It was more thermostable and very resistant to the chemical denaturant urea. Amino acid sequence comparison of stMS with four mesophilic streptomycete MSs indicated that they share 70.9-91.4% amino acid identities, with stMS possessing slightly more charged residues (approximately 31%) than its mesophilic counterparts (approximately 28-29%). Seven charged residues (E85, R187, R209, H239, H364, R382 and K520) that were unique to stMS may be selectively and strategically placed to support its peculiar characteristics.

Recombinant Plasmodium falciparum NADP-dependent isocitrate dehydrogenase is active and harbours a unique 26 amino acid tail.

During infection, Plasmodium spp. require reducing equivalents such as NADPH to support the function of specific enzymes in overcoming oxidative stress. The catalysis of isocitrate by the NADP-dependent isocitrate dehydrogenase of Plasmodium falciparum (pfICDH) generates NADPH and is thus crucial for the parasite's survival and pathogenecity. In this study, pfICDH was cloned from a clinical isolate of P. falciparum. This was facilitated by designing primers based on the P. falciparum genome sequence resource PlasmoDB. DNA sequence of the cloned gene revealed an ORF that encodes a protein of 468 aa. Furthermore, after expression in Esherichia coli BL21, enzyme assays of cell-free extracts confirmed the overexpression and function of pfICDH. Further, pfICDH purified by affinity chromatography retained its enzyme activity. Substitution of NADP for NAD, or the use of EDTA, in enzyme assays abolished pfICDH activity. ATP and chloroquine, as well as cupric and argentic ions, inhibited pfICDH activity. Phylogenetic analysis revealed high primary structure homology (45-97%) among genes coding for eukaryal NADP-dependent ICDH, and the occurrence of three subfamilies of ICDH genes. Interestingly, there were significant sequence dissimilarities between pfICDH and its mammalian or bacterial homologs, particularly at the N- and C-termini. Confirming the functionality of the cloned pfICDH, and asserting its distance from the human homolog by molecular definitions, are important prerequisites for promoting this gene as a drug target screen.

C-terminus modification of Streptomyces clavuligerus deacetoxycephalosporin C synthase improves catalysis with an expanded substrate specificity.

The biosynthesis of cephalosporins is catalyzed by deacetoxycephalosporin C synthase (DAOCS). Based on computational, biochemical, and structural analyses, it has been proposed that modification of the C-terminus of DAOCS might be a constructive strategy for engineering improvement in enzyme activity. Therefore, five hydrophilic residues namely N301, Y302, N304, R306, and R307 located in proximity to the C-terminus of Streptomyces clavuligerus DAOCS (scDAOCS) were selected and each substituted with a hydrophobic leucine residue. Substitutions at positions 304, 306, and 307 created mutant scDAOCSs with improved efficiencies in penicillin analog conversion up to 397%. And since it has been previously advocated that the C-terminus is crucial for guiding substrate entry, a truncated mutant DAOCS was constructed to assess its involvement. The truncation of the C-terminus at position 310 in the wild-type scDAOCS resulted in reduction of indiscriminate conversion of penicillin analog but this defect was compensated by the replacement of asparagine with leucine at position 304.

Purification and characterization of recombinant malate synthase enzymes from Streptomyces coelicolor A3(2) and S. clavuligerus NRRL3585.

Malate synthases (MS) from Streptomyces coelicolor A3(2) and S. clavuligerus NRRL3585 were cloned by polymerase chain reaction into a glutathione S-transferase (GST) fusion expression vector and heterologously expressed in Escherichia coli. The fusion GST-MS construct improved the soluble expression of MS by approximately 10-fold compared to the soluble expression of nonfusion MS. With the significant improvement in levels of soluble MS, purification and subsequent cleavage of recombinant MS from GST were facilitated in this study. Using purified enzymes, optimized parameters, which achieved maximal specific activity, were established in the enzymatic assay for streptomycete MS. The average purified specific activities of S. coelicolor and S. clavuligerus MS were 26199 and 11821 nmol/mg min, respectively. Furthermore, enzymatic analysis revealed that the two streptomycete MS displayed a similar Km value for acetyl-CoA, but S. coelicolor MS had a Km value for glyoxylate that is approximately sixfold higher than S. clavuligerus MS.

Cloning, heterologous expression and purification of an isocitrate lyase from Streptomyces clavuligerus NRRL 3585.

The glyoxylate cycle comprising isocitrate lyase (ICL) and malate synthase (MS) is an anaplerotic pathway essential for growth on acetate as the sole carbon source. The aceB gene, which encodes malate synthase has been previously cloned from Streptomyces clavuligerus NRRL 3585 and characterized. In this study, the aceA gene, encoding ICL from S. clavuligerus NRRL 3585, was obtained via genome walking experiments and PCR. The fully sequenced open reading frame encodes 436 amino acids with a deduced M(r) of 47.5 kDa, consistent with the observed M(r) (49-67.5 kDa) of most ICL enzymes reported so far. The cloned aceA gene was expressed in Escherichia coli BL21(lambdaDE3) cells, from which ICL was purified as a His-tagged product and its functionality demonstrated. Furthermore, the relationship between the carbon sources, growth and ICL activity in S. clavuligerus were investigated. Rapid growth was observed when the cells were cultured on 0.5% (w/v) glycerol, while delayed growth was observed when cells were grown on 0.5% (w/v) acetate. However, in both cases, high levels of ICL activity coincided with a cessation of growth, suggesting a late physiological role played by ICL in the natural host, S. clavuligerus.

Replacement of tyrosine-197 and the corresponding tyrosine-195 to isoleucine in Cephalosporium acremonium and Streptomyces clavuligerus isopenicillin N synthase.

Isopenicillin N synthase (IPNS) is one of the key enzymes in the penicillin and cephalosporin biosynthetic pathway which catalyses the conversion of delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine to isopenicillin N. The IPNS from Penicillium chrysogenum 23X-80-269-37-2, a high penicillin V-producer, was found to possess an isoleucine residue instead of tyrosine at position 195. An attempt to increase the specific activity of IPNS from Cephalosporium acremonium and Streptomyces clavuligerus was undertaken by altering the corresponding tyrosine residue to an isoleucine at the corresponding location. Unfortunately, no apparent increase in specific activity was encountered when the purified mutant enzymes were analysed and thus, this amino acid difference is likely not responsible for high specific activity in IPNS.