Awareness and preparedness of healthcare workers against the first wave of the COVID-19 pandemic: A cross-sectional survey across 57 countries

BACKGROUND

Since the COVID-19 pandemic began, there have been concerns related to the preparedness of healthcare workers (HCWs). This study aimed to describe the level of awareness and preparedness of hospital HCWs at the time of the first wave.

METHODS

This multinational, multicenter, cross-sectional survey was conducted among hospital HCWs from February to May 2020. We used a hierarchical logistic regression multivariate analysis to adjust the influence of variables based on awareness and preparedness. We then used association rule mining to identify relationships between HCW confidence in handling suspected COVID-19 patients and prior COVID-19 case-management training.

RESULTS

We surveyed 24,653 HCWs from 371 hospitals across 57 countries and received 17,302 responses from 70.2% HCWs overall. The median COVID-19 preparedness score was 11.0 (interquartile range [IQR] = 6.0-14.0) and the median awareness score was 29.6 (IQR = 26.6-32.6). HCWs at COVID-19 designated facilities with previous outbreak experience, or HCWs who were trained for dealing with the SARS-CoV-2 outbreak, had significantly higher levels of preparedness and awareness (p<0.001). Association rule mining suggests that nurses and doctors who had a 'great-extent-of-confidence' in handling suspected COVID-19 patients had participated in COVID-19 training courses. Male participants (mean difference = 0.34; 95% CI = 0.22, 0.46; p<0.001) and nurses (mean difference = 0.67; 95% CI = 0.53, 0.81; p<0.001) had higher preparedness scores compared to women participants and doctors.

INTERPRETATION

There was an unsurprising high level of awareness and preparedness among HCWs who participated in COVID-19 training courses. However, disparity existed along the lines of gender and type of HCW. It is unknown whether the difference in COVID-19 preparedness that we detected early in the pandemic may have translated into disproportionate SARS-CoV-2 burden of disease by gender or HCW type.

Constitutive expression and cell-surface display of a bacterial β-mannanase in Lactobacillus plantarum

BACKGROUND

Lactic acid bacteria (LAB) are important microorganisms in the food and beverage industry. Due to their food-grade status and probiotic characteristics, several LAB are considered as safe and effective cell-factories for food-application purposes. In this present study, we aimed at constitutive expression of a mannanase from Bacillus licheniformis DSM13, which was subsequently displayed on the cell surface of Lactobacillus plantarum WCFS1, for use as whole-cell biocatalyst in oligosaccharide production.

RESULTS

Two strong constitutive promoters, Pgm and SlpA, from L. acidophilus NCFM and L. acidophilus ATCC4356, respectively, were used to replace the inducible promoter in the lactobacillal pSIP expression system for the construction of constitutive pSIP vectors. The mannanase-encoding gene (manB) was fused to the N-terminal lipoprotein anchor (Lp_1261) from L. plantarum and the resulting fusion protein was cloned into constitutive pSIP vectors and expressed in L. plantarum WCFS1. The localization of the protein on the bacterial cell surface was confirmed by flow cytometry and immunofluorescence microscopy. The mannanase activity and the reusability of the constructed L. plantarum displaying cells were evaluated. The highest mannanase activities on the surface of L. plantarum cells obtained under the control of the Pgm and SlpA promoters were 1200 and 3500 U/g dry cell weight, respectively, which were 2.6- and 7.8-fold higher compared to the activity obtained from inducible pSIP anchoring vectors. Surface-displayed mannanase was shown to be able to degrade galactomannan into manno-oligosaccharides (MOS).

CONCLUSION

This work demonstrated successful displaying of ManB on the cell surface of L. plantarum WCFS1 using constitutive promoter-based anchoring vectors for use in the production of manno-oligosaccharides, which are potentially prebiotic compounds with health-promoting effects. Our approach, where the enzyme of interest is displayed on the cell surface of a food-grade organism with the use of strong constitutive promoters, which continuously drive synthesis of the recombinant protein without the need to add an inducer or change the growth conditions of the host strain, should result in the availability of safe, stable food-grade biocatalysts.

Fermentability of a Novel Galacto-Oligosaccharide Mixture by Lactobacillus spp. and Bifidobacterium spp

This study aimed to investigate the specific growth stimulation of certain desired intestinal bacteria by a novel galacto-oligosaccharide mixture, which was produced with a β-galactosidase from a potential probiotic Lactobacillus isolate that contained mainly oligosaccharides of β-1,3 and β-1,6 glycosidic linkages (termed Lb-GOS) using single-strain fermentations. The composition of this Lb-GOS mixture was 33.5% disaccharides, 60.5% trisaccharides, 4.8% tetrasaccharides, and 1.0% pentasaccharides with a negligible amount of monosaccharides, lactose, and lactobionic acid (0.3%). Eight Lactobacillus spp. strains and three Bifidobacterium spp. strains were used in single-strain fermentations to determine the fermentation activity scores of this Lb-GOS preparation compared to two commercially available prebiotic mixtures, 4′GOS-P and Vivinal GOS (V-GOS). The highest scores were obtained when L. reuteri Lb46 and the two Bifidobacterium strains, B. animalis subsp. lactis Bif1 and Bif3, were grown on these galacto-oligosaccharide mixtures. In addition, the Lb-GOS mixture was found to have higher fermentation activity scores; hence, it stimulated the growth of these probiotic strains more than 4′GOS-P and V-GOS, which may be attributed to the different glycosidic linkage types that are found in the Lb-GOS mixture compared to the other two commercial preparations. These findings suggested that the Lb-GOS mixture that is described in this work should be of interest for the formulations of new carbohydrate-based functional food ingredients.

Display of a β-mannanase and a chitosanase on the cell surface of Lactobacillus plantarum towards the development of whole-cell biocatalysts

BACKGROUND

Lactobacillus plantarum is considered as a potential cell factory because of its GRAS (generally recognized as safe) status and long history of use in food applications. Its possible applications include in situ delivery of proteins to a host, based on its ability to persist at mucosal surfaces of the human intestine, and the production of food-related enzymes. By displaying different enzymes on the surface of L. plantarum cells these could be used as whole-cell biocatalysts for the production of oligosaccharides. In this present study, we aimed to express and display a mannanase and a chitosanase on the cell surface of L. plantarum.

RESULTS

ManB, a mannanase from Bacillus licheniformis DSM13, and CsnA, a chitosanase from Bacillus subtilis ATCC 23857 were fused to different anchoring motifs of L. plantarum for covalent attachment to the cell surface, either via an N-terminal lipoprotein anchor (Lp_1261) or a C-terminal cell wall anchor (Lp_2578), and the resulting fusion proteins were expressed in L. plantarum WCFS1. The localization of the recombinant proteins on the bacterial cell surface was confirmed by flow cytometry and immunofluorescence microscopy. The highest mannanase and chitosanase activities obtained for displaying L. plantarum cells were 890 U and 1360 U g dry cell weight, respectively. In reactions with chitosan and galactomannans, L. plantarum CsnA- and ManB-displaying cells produced chito- and manno-oligosaccharides, respectively, as analyzed by high performance anion exchange chromatography (HPAEC) and mass spectrometry (MS). Surface-displayed ManB is able to break down galactomannan (LBG) into smaller manno-oligosaccharides, which can support growth of L. plantarum.

CONCLUSION

This study shows that mannanolytic and chitinolytic enzymes can be anchored to the cell surface of L. plantarum in active forms. L. plantarum chitosanase- and mannanase-displaying cells should be of interest for the production of potentially 'prebiotic' oligosaccharides. This approach, with the enzyme of interest being displayed on the cell surface of a food-grade organism, may also be applied in production processes relevant for food industry.

Lipidomic and transcriptomic analyses of Chlamydomonas reinhardtii under heat stress unveil a direct route for the conversion of membrane lipids into storage lipids

Studying how photosynthetic cells modify membrane lipids in response to heat stress is important to understand how plants and microalgae adapt to daily fluctuations in temperature and to investigate new lipid pathways. Here, we investigate changes occurring in lipid molecular species and lipid metabolism genes during early response to heat stress in the model photosynthetic microorganism Chlamydomonas reinhardtii. Lipid molecular species analyses revealed that, after 60 min at 42 °C, a strong decrease in specific polyunsaturated membrane lipids was observed together with an increase in polyunsaturated triacylglycerols (TAGs) and diacylglycerols (DAGs). The fact that decrease in the major chloroplastic monogalactosyldiacylglycerol sn1-18:3/sn2-16:4 was mirrored by an accumulation of DAG sn1-18:3/sn2-16:4 and TAG sn1-18:3/sn2-16:4/sn3-18:3 indicated that newly accumulated TAGs were formed via direct conversion of monogalactosyldiacylglycerols to DAGs then TAGs. Lipidomic analyses showed that the third fatty acid of a TAG likely originated from a phosphatidylethanolamine or a diacylglyceryl-O-4'-(N,N,N,-trimethyl)-homoserine betaine lipid species. Candidate genes for this TAG synthesis pathway were provided through comparative transcriptomic analysis and included a phospholipase A2 homolog and the DAG acyltransferase DGTT1. This study gives insights into the molecular events underlying changes in membrane lipids during heat stress and reveals an alternative route for TAG synthesis.

Heterologous expression of a recombinant lactobacillal β-galactosidase in Lactobacillus plantarum: effect of different parameters on the sakacin P-based expression system

Background

Two overlapping genes lacL and lacM (lacLM) encoding for heterodimeric β-galactosidase from Lactobacillus reuteri were previously cloned and over-expressed in the food-grade host strain Lactobacillus plantarum WCFS1, using the inducible lactobacillal pSIP expression system. In this study, we analyzed different factors that affect the production of recombinant L. reuteri β-galactosidase.

Results

Various factors related to the cultivation, i.e. culture pH, growth temperature, glucose concentration, as well as the induction conditions, including cell concentration at induction point and inducer concentration, were tested. Under optimal fermentation conditions, the maximum β-galactosidase levels obtained were 130 U/mg protein and 35–40 U/ml of fermentation broth corresponding to the formation of approximately 200 mg of recombinant protein per litre of fermentation medium. As calculated from the specific activity of the purified enzyme (190 U/mg), β-galactosidase yield amounted to roughly 70% of the total soluble intracellular protein of the host organism. It was observed that pH and substrate (glucose) concentration are the most prominent factors affecting the production of recombinant β-galactosidase.

Conclusions

The over-expression of recombinant L. reuteri β-galactosidase in a food-grade host strain was optimized, which is of interest for applications of this enzyme in the food industry. The results provide more detailed insight into these lactobacillal expression systems and confirm the potential of the pSIP system for efficient, tightly controlled expression of enzymes and proteins in lactobacilli.

Identification of a natural intergenotypic recombinant hepatitis delta virus genotype 1 and 2 in Vietnamese HBsAg-positive patients

Hepatitis D virus (HDV) infection is acquired as a co- /superinfection of Hepatitis B virus (HBV) and can modulate the pathophysiology of chronic hepatitis B and related liver diseases including hepatocellular carcinoma. Among the eight distinct HDV genotypes reported, relatively few studies have attempted to investigate the prevalence of HDV mixed genotypes and RNA recombination of HDV. With a recorded prevalence of 10-20% HBV infection in Vietnam, this study investigated the HDV variability, HDV genotypes and HDV recombination among twenty-one HDV isolates in Vietnamese HBsAg-positive patients. HDV subgenomic and full-length genome sequences were obtained using newly established HDV-specific RT-PCR techniques. The nucleotide homology was observed from 74.6% to 99.4% among the investigated full-length genome of the HDV isolates. We observed HDV genotype 1 and HDV genotype 2 in the investigated Vietnamese patients. Although no HDV genotype mixtures were observed, we report here a newly identified recombinant of HDV genotypes (HDV 1 and HDV 2). The identified recombinant HDV isolate C03 revealed sequence homology to both HDV genotype 1 (nt1 to nt907) and HDV genotype 2 (nt908 to nt1675; HDAg coding region) with a breakpoint at nt908. Our findings demonstrate the prevalence of intergenotypic recombination between HDV genotypes 1 and 2 in a Vietnamese HBsAg-positive patient. Extended investigation on the distribution and prevalence of HDV, HDV mixed genotypes and recombinant HDV genotypes in a larger Vietnamese population offers vital insights into understanding of the micro-epidemiology of HDV and subsequent pathophysiology in chronic HBV- /HDV-related liver diseases.

2,3,7,8-Tetrachlorodibenzo-p-dioxin in breast milk increases autistic traits of 3-year-old children in Vietnam

Dioxin levels in the breast milk of mothers residing near a contaminated former airbase in Vietnam remain much higher than in unsprayed areas, suggesting high perinatal dioxin exposure for their infants. The present study investigated the association of perinatal dioxin exposure with autistic traits in 153 3-year-old children living in a contaminated area in Vietnam. The children were followed up from birth using the neurodevelopmental battery Bayley-III. The high-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposed groups (⩾3.5 pg per g fat) showed significantly higher Autism Spectrum Rating Scale (ASRS) scores for both boys and girls than the mild-TCDD exposed groups, without differences in neurodevelopmental scores. In contrast, the high total dioxin-exposed group, indicated by polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs)--the toxic equivalents (TEQ) levels⩾17.9 pg-TEQ per g fat, had significantly lower neurodevelopmental scores than the mild-exposed group in boys, but there was no difference in the ASRS scores. The present study demonstrates a specific impact of perinatal TCDD on autistic traits in childhood, which is different from the neurotoxicity of total dioxins (PCDDs/Fs).

Enhanced payload of lipid nanocarriers using supersaturated solution prepared by solvent-mediated method

With the aim to effectively enhance the payload for nanocarriers, supersaturated deltamethrin (SSD) solution was prepared using the solvent-mediated method to produce lipid nanocarriers by a combination method of homogenization and sonication. In this study, deltamethrin was used as an active ingredient, corn oil was used as a lipid medium, soybean lecithin and Tween-80 were used as surfactants. At 25°C, the solubility of deltamethrin in SSD solution prepared by solvent-mediated method was 3.4 times and 1.5 times higher than that in saturated deltamethrin (SD) solution and that in SSD solution prepared by thermal-mediated method, respectively. Therefore, compared to the use of SD solution for the production of nanocarriers, the use of SSD solution significantly enhanced the payload, while keeping the encapsulation efficiency high. Particularly, nanocarriers produced from SSD solution prepared by solvent-mediated method had the higher payload of 2.1 times and 4.4 times compared with preparations using SSD solution prepared by thermal-mediated method and SD solution, respectively.

Implementation of sepsis management guideline in a community-based teaching hospital - can education be potentially beneficial for septic patients?

OBJECTIVE

To assess clinical outcomes associated with the implementation of the sepsis management guideline in a community-based hospital. In addition, evaluate the utility and effectiveness of a Sepsis Education Program.

RESEARCH DESIGN AND METHODS

This is an observational cohort study of patients presenting to the Emergency Department at a community-based teaching centre meeting severe sepsis or septic shock criteria. A quality improvement programme consisting of a comprehensive Sepsis Education Program based on recommendations from the Surviving Sepsis Campaign was implemented and evaluated. Patients were identify by the admission diagnosis and were evaluated over two time periods (7/2003-6/2004 and 7/2005-6/2006) and to show clinical outcomes before and after implementation of the sepsis guideline/quality improvement programme.

RESULTS

A total of 96 patients with severe sepsis (34 control group and 62 SSC group) were included. Both groups had similar intensive care unit (ICU)-length of stay (3 vs. 3 days, p = 0.647). Patients who required mechanical ventilation (MV) had similar MV time (4 vs. 3.5 days p = 0.349). A greater percentage of survival was found in the SSC group [45% vs. 73% (p = 0.006)]. Patient received similar care with regards to appropriate early antibiotics (85% vs. 90%, p 0.459). The main difference between the two group was the early fluid resuscitation (2 l vs. 3 l, p = 0.006) over the first 3 h and a difference remained significant at 6 h (4.2 l vs. 6.3 l, p = 0.013).

CONCLUSIONS

In a community based teaching hospital, implementing the surviving sepsis campaign guideline through an education programme was feasible and resulted in early therapy with aggressive fluid administration and appropriate antibiotics. The Sepsis Education Program resulted in early therapeutic interventions and contributed to the survival benefits.

How to manage medications in the setting of liver disease with the application of six questions

OBJECTIVE

Reviewing the current literature to guide clinicians managing medications in the setting of liver disease.

LITERATURE SOURCES

Using the terms liver disease, medication management, and therapeutic monitoring, a literature review was conducted to identify peer-reviewed articles in MEDLINE (1966-April 2009). Reference citations were reviewed as an additional resource. Published English-language literatures, articles and trials were reviewed. Emphasis was placed on prospective, randomised, double-blind, placebo-controlled clinical trials.

QUESTION SYNTHESIS

An informed decision on how to manage medications in the setting of liver disease should account for changes that transpire in a medication's first-pass metabolism, protein binding, volume of distribution, clearance and pharmacodynamic interactions. To incorporate these issues within one's thought process, clinicians can utilise the following six questions to evaluate a medication use: (i) Is the patient experiencing acute or chronic liver failure? (ii) Does the drug have high hepatic first-pass metabolism? (iii) Is the medication highly protein-bound? (iv) Is there a change in the volume of distribution for the medication? (v) Is the clearance of the medication significantly altered? and (vi) Is there a pharmacodynamic interaction with the medication?

CONCLUSIONS

The introduction and use of six clinically relevant questions in the setting of liver disease can serve as a guide to clinicians who manage patients with liver disease.

Nesiritide utilization evaluation in a university teaching hospital

BACKGROUND AND OBJECTIVES

Nesiritide is a new vasodilator approved for decompensated heart failure (DHF). Compared with nitroglycerin, nesiritide improves haemodynamics and symptoms in the first 3 h of therapy. However, nesiritide is more expensive than nitroglycerin (US$380-1500 daily vs. US$2-5 daily). Since its approval in the US in late 2001, nesiritide use has increased dramatically in our institution. Nesiritide has become a focus of our multidisciplinary drug utilization initiative, aimed at performing a nesiritide utilization evaluation (NUE) and developing a nesiritide usage guideline.

METHODS

Medical records of patients who received nesiritide from 1 October 2003 to 31 March 2004 were reviewed. Nesiritide utilization pattern was presented to the initiative group for guideline development.

RESULTS

A total of 162 records were reviewed. A 22.6% of inappropriate usage was reported. The most significant inappropriate usage was in patients who received the agent for precardiac valvular surgery optimization, followed by those for diuresis in non-cardiac-related fluid overload states. The median duration of nesiritide therapy was 6 days (range 1-94). The median length of stay (LOS) in our institution was 14 days (National statistics DHF LOS: 5.3 days). Eliminating inappropriate nesiritide usage can lead to a potential of US$141 886 savings per year.

CONCLUSION

Based on the results, a 48-h nesiritide restriction policy was implemented. Usage beyond 48 h requires Heart Failure Service approval. Future NUE will evaluate the effectiveness of this policy. The overall management of DHF also needs to be evaluated to improve efficiency of care.

Sulfide-mediated dehydrative glycosylation

The development of a new method for glycosylation with 1-hydroxy glycosyl donors employing dialkyl sulfonium reagents is described. The process employs the reagent combination of a dialkyl sulfide and triflic anhydride to effect anomeric bond constructions. This controlled dehydrative coupling of various C(1)-hemiacetal glycosyl donors and nucleophilic acceptors proceeds by way of a sulfide-to-sulfoxide oxidation process in which triflic anhydride serves as the oxidant.

Age at first marriage in Viet Nam: patterns and determinants

"Using data from the 1991 Viet Nam Life History Survey, this article examines the patterns and determinants of age at first marriage. It shows that socio-economic and political changes during the last few decades are associated with a shift to older ages of first marriage. It identifies regional variations and discusses the significant impact of warfare on the country's age patterns of marriage. It concludes by bringing out the implications of the study for policy purposes." The full text is of this article is available electronically through www.undp.org/popin.

Design and application of a low-temperature Peltier-cooling microscope stage

A light microscopy system has been designed for freezing and lyophilization studies of protein pharmaceuticals. The system consists of a cascade of four Peltier thermoelectric modules in the lyophilization cell to freeze samples to -60 degrees C, controllers to regulate temperature and pressure conditions, and a video camera to record the events under study. Specific demonstration of the system was conducted using recombinant CD4-IgG and human growth hormone (hGH) as model proteins. Observations of recrystallization during warming of frozen CD4-IgG solution and lyophilization of hGH solution are discussed. These examples demonstrate that the system is a useful tool for the fundamental understanding of freezing and lyophilization of protein pharmaceuticals.

Surface denaturation at solid-void interface--a possible pathway by which opalescent particulates form during the storage of lyophilized tissue-type plasminogen activator at high temperatures

During protein lyophilization, it is common practice to complete the freezing step as fast as possible in order to avoid protein denaturation, as well as to obtain a final product of uniform quality. We report a contradictory observation made during lyophilization of recombinant tissue-type plasminogen activator (t-PA) formulated in arginine. Fast cooling during lyophilization resulted in a lyophilized product that yielded more opalescent particulates upon long term storage at 50 degrees C, under a 150 mTorr nitrogen seal gas environment. Fast cooling also resulted in a lyophilized cake with a large internal surface area. Studies on lyophilized products containing 1% (w/w) residual moisture and varying cake surface areas (0.22-1.78 m2/gm) revealed that all lyophilized cakes were in an amorphous state with similar glass transition temperatures (103-105 degrees C). However, during storage the rate of opalescent particulate formation in the lyophilized product (as determined by UV optical density measurement in the 360 to 340 nm range for the reconstituted solution) was proportional to the cake surface area. We suggest that this is a surface-related phenomenon in which the protein at the solid-void interface of the lyophilized cake denatures during storage at elevated temperatures. Irreversible denaturation at the ice-liquid interface during freezing in lyophilization is unlikely to occur, since repeated freezing/thawing did not show any adverse effect on the protein. Infrared spectroscopic analysis could not determine whether protein, upon lyophilization, at the solid-void interface would still be in a native form.