The association of ABO and Rhesus blood type with the risks of developing SARS-CoV-2 infection: A meta-analysis.

Coronavirus Disease 2019 (COVID-19) has been spreading like a wildfire everywhere in the globe. It has been challenging the global health care system ever since the end of 2019, with its virulence and pathogenicity. Recent studies have shown the association between ABO blood group, Rhesus blood type and susceptibility to COVID-19 infection. Various studies and few meta-analyses have been done and some might be inconsistent; therefore, this meta-analysis was done to assess the relationship between different ABO and Rhesus blood types on the susceptibility to COVID-19 infections. This meta-analysis assessed the odds ratio of COVID-19 infection of different ABO and Rhesus blood types. Subgroup analyses according to (1) age and gender matched; (2) different blood group antigens; (3) Rhesus positive and negative of each blood group were carried out. Publication bias and Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) were also done to assess the risk of bias in these publications. It was found that blood group A showed significant difference in odds ratio of COVID-19 infection (OR, 1.16; 95% CI, 1.08-1.24). Blood group AB showed significant difference in odds ratio when studies with lower QUADAS-2 score were removed. This means that populations with blood group A and AB are more likely to be infected with COVID-19. As there is a higher tendency that blood group A and AB to be infected with COVID- 19, precautious care should be taken by these populations.

The association of ABO and Rhesus blood type with the risks of developing SARS-CoV-2 infection: A meta-analysis

@#Coronavirus Disease 2019 (COVID-19) has been spreading like a wildfire everywhere in the globe. It has been challenging the global health care system ever since the end of 2019, with its virulence and pathogenicity. Recent studies have shown the association between ABO blood group, Rhesus blood type and susceptibility to COVID-19 infection. Various studies and few meta-analyses have been done and some might be inconsistent; therefore, this meta-analysis was done to assess the relationship between different ABO and Rhesus blood types on the susceptibility to COVID-19 infections. This meta-analysis assessed the odds ratio of COVID-19 infection of different ABO and Rhesus blood types. Subgroup analyses according to (1) age and gender matched; (2) different blood group antigens; (3) Rhesus positive and negative of each blood group were carried out. Publication bias and Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) were also done to assess the risk of bias in these publications. It was found that blood group A showed significant difference in odds ratio of COVID-19 infection (OR, 1.16; 95% CI, 1.08-1.24). Blood group AB showed significant difference in odds ratio when studies with lower QUADAS-2 score were removed. This means that populations with blood group A and AB are more likely to be infected with COVID-19. As there is a higher tendency that blood group A and AB to be infected with COVID19, precautious care should be taken by these populations.

Applying interprofessional simulation to improve knowledge, attitude and practice in hospital- acquired infection control among health professionals.

BACKGROUND: This study aimed at determining the effectiveness of an innovative approach using interprofessional simulation scenarios (IPSS) in improving knowledge, attitude, and practice (KAP) of hospital-acquired infection control (HAIC) among health professionals. METHODS: The interventional study was conducted in a teaching hospital in Malaysia. Purposive sampling was used to recruit participants from surgical, intensive care, and other units. Thirty-six health professionals in the experimental and forty in the control group completed the study. All subjects participated in an interactive lecture and demonstrated four IPSS on HAIC i.e. (i) taking blood specimen (ii) bedsore dressing (iii) collecting sputum for acid-fast bacilli and (iv) intermittent bladder catheterization. Each team consisted of a doctor and a nurse. A self-administered questionnaire on KAP on HAIC was completed by respondents during the pre-, immediately and, post-intervention. An independent t-test was conducted to measure the significance between the experimental and control group. RESULTS: The mean scores for KAP among the experimental group increased following the intervention. Significant differences in scores were seen between the two groups post-intervention (p < 0.05). Overall, using the four procedures as surrogates, the interprofessional learning approach in HAIC intervention showed improvement among the participants in the experimental group following structured instructions. The IPSS approach in HAIC clearly shows its relevance in improving learning outcomes. CONCLUSIONS: Well-designed interprofessional simulated scenarios can be effective in skills training in improving KAP in HAIC among health professionals.

Evaluation of Tween 80 incorporated media to increase pathogen isolation from peritoneal fluid of CAPD patients at Hospital Kuala Lumpur.

INTRODUCTION: Continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis remains a major complication in patients on CAPD leading to increased morbidity and mortality. Successful therapy of peritonitis is highly dependent on a positive microbiological culture because narrow spectrum antibiotics are essential to efficiently combat infection. Therefore, this study evaluated the performance of Tween 80 containing media at three different concentrations (0.1%, 1.0% and 2.0%) to increase the pathogen yield from peritoneal fluid in comparison with the standard culture media. MATERIALS AND METHODS: Peritoneal fluid samples (n=121) obtained from CAPD patients suspected of peritonitis at Hospital Kuala Lumpur were analysed macroscopically and microscopically prior to culture. All samples were cultured on seven different culture media, including sheep blood agar, MacConkey agar, Sabouraud dextrose agar, brain heart infusion agar and Tween 80 incorporated blood agar. All plates were incubated at an optimum temperature up to 48 hours. RESULTS AND CONCLUSION: Among all the culture media investigated, 0.1% to 2.0% Tween 80 incorporated blood agar yielded the highest positive culture (23/121) in comparison with all other standard media, thus lowering the negative culture rate among CAPD patients. Statistical analysis by Chi Square revealed significant differences (p <0.001) between the three concentrations of Tween 80 tested in this study. Among the three different concentrations of Tween 80 optimised in this study, blood agar containing 0.1% Tween 80 generated the best results, achieved by optimum growth of all Gram-positive organisms, Gram-negative organisms and yeast cells simultaneously. Using a small amount of detergent at low cost significantly increased the pathogen yield during CAPD-associated peritonitis.

Self-assessment, attitude and perception of interprofessional learning in hospital acquired infection control practices among health professionals in Klang Valley, Malaysia.

BACKGROUND: Interprofessional learning (IPL) is a key challenge in Malaysia in incorporating the current profession-specific medical education into the interprofessional learning curriculum. Safe practices would be enhanced with improved collaboration among the health professionals when they learn with, from, and about each other. The main objective of this study was to determine the significant differences in self-assessment, attitude, and perception of interprofessional learning among doctors and nurses in a teaching hospital in Klang Valley, Malaysia. The second objective was to determine if there is any significant difference in the selected demography factors, mean and total scores between doctors and nurses in self-assessment, attitude, and perceptions of IPL aspects. METHODS: A total of doctors (39) and nurses (37) were recruited for an interventional study on the interprofessional learning approach on hospital acquired infection control. The participants responded to the University of West England Interprofessional (UWEIP) questionnaire at baseline consisting of four dimensions in IPL aspects; Self-assessment on communication and teamwork skills (CTW), interprofessional learning (IPL), interprofessional interaction (IPI), and interprofessional relationship (IPR). The Cronbach alpha value for the total questionnaire was established at 0.79. RESULTS: The majority of doctors scored positive in CTW, IPL, IPR, and neutral in IPI. Nurses' also recorded the highest positive scores in CTW, IPL, and IPR, and neutral in IPI. Negative scores were found in CTW and IPI. A significant difference was revealed between doctors and nurses in IPL attitude; p = 0.024 and there was no significant difference in other dimensions (p > .05). Results also found a significant difference between participants' and non-participants of IPL training sessions; p = 0.009. CONCLUSIONS: This study revealed the infusion of interprofessional learning training among the health professionals displayed better self-assessments, attitudes, and perceptions towards collaborative practices.

Diagnosis of neonatal meningitis: is it time to use polymerase chain reaction?

Group B Streptococcus (GBS) is a predominant causative pathogen of neonatal meningitis that is associated with a high rate of mortality and morbidity. The establishment of antenatal screening and intrapartum chemoprophylaxis has led to a significant reduction in the incidence rate of invasive GBS disease in developed countries. However, these strategies are not routinely practiced in most developing countries. To ensure good recovery of infants affected with GBS, a prompt diagnostic strategy and appropriate therapy are essential. We highlight here the case of a preterm male infant diagnosed with early-onset of GBS meningitis diagnosed by using polymerase chain reaction (PCR) method on the cerebrospinal fluid (CSF) of the infant. Initially the pathogen was not isolated in both blood and CSF cultures as sampling was performed after the administration of antibiotics. Hence, PCR was a crucial diagnostic test in facilitating the detection of the pathogen in CSF. We believe that PCR is a potentially fast and precise diagnostic method for infection in a newborn.

Susceptibility patterns of anaerobes isolated from clinical specimens in tertiary Hospital, Malaysia.

INTRODUCTION: The susceptibility patterns of anaerobes are becoming less predictable due to the emergence of anaerobic resistance trends to antibiotics; hence increasing the importance of the isolation and antimicrobial susceptibility testing of anaerobes. MATERIALS AND METHODS: This study investigated the isolation of anaerobes from the clinical specimens of Hospital Sungai Buloh, Malaysia, from January 2015 to December 2015. All isolates were identified using the API 20A system (bioMérieux, France). Antimicrobial susceptibility testing was performed using the E-test (bioMérieux, France). RESULTS: The proportion of obligate anaerobes isolated from the clinical specimens was 0.83%. The Gram-positive anaerobes were most susceptible to vancomycin and imipenem, showing 100% sensitivity to these antimicrobials, followed by clindamycin (86.3%), penicillin (76.7%), and metronidazole (48.9%). Meanwhile, Gram-negative anaerobes were most susceptible to metronidazole (96%) followed by imipenem (89%), clindamycin (79%), and ampicillin (32%). The present study also showed that 3 out of 12 Bacteroides fragilis isolates were resistant to imipenem. CONCLUSION: This study demonstrated the differences in the susceptibility patterns of anaerobes towards commonly used antimicrobials for the treatment of anaerobic infections. In summary, continuous monitoring of antimicrobial resistance trends among anaerobes is needed to ensure the appropriateness of treatment.

Application of Theory in Studies of Healthcare Built Environment Research.

We aimed to examine the nature and extent of theory application in studies of built environment attributes and impact on adults in healthcare facilities. Many varied theories are described when providing the rationale for research into built environments in healthcare. Uncertainty exists around the right theory to frame a research question, alignment with measurement tools, and whether healthcare setting makes a difference. This poses challenges to researchers seeking to build the evidence base for built environment design that benefits patients and staff. Our multidisciplinary review team scoped the literature to determine how theories are used to inform research investigating the impact of the built environment of healthcare on adults. When researchers recorded theory at development of the study question, in data collection, and in data analysis/interpretation, we called this explicitly theory-based application. Synthesis occurred using a narrative approach. Overall, we found 17 diverse theories named in studies. Explicitly theory-based use occurred with eight theories, comprising 47% of all theories used. Five theories were named more frequently in studies out of all theories identified. In 20% of studies, theory was not used explicitly during the research inquiry. We argue that researchers must continue to strive toward explicit use of theories, similar to development of other health interventions that employ multifactorial components.

Time-kill and post-antibiotic effect of colistin at different static concentrations in in vitro Acinetobacter baumannii.

Nosocomial infection caused by Acinetobacter baumannii is common among immunocompromised patients. Treatment strategy is limited due to rapid resistance development and lack of novel antibiotic. Colistin has been the last line therapy with good in vitro activity against infections caused by multi-drug resistance A. baumannii. However, pharmacological updates are required to support dosing optimisation. This study aimed to determine the time-kill kinetic and resistance development after antibiotic exposure as well as post-antibiotic effect of colistin at different static concentrations in in vitro A. baumannii system. The static in vitro time-kill and post-antibiotic effect experiments were conducted against two clinical isolates as well as one reference isolate ATCC 19606. Time-kill and postantibiotic effect were studied at colistin concentrations ranging from 0.25MIC to 16.0MIC and 0.5MIC to 4.0MIC, respectively. Post-exposure resistance development was examined in time-kill study. Killing activity and post-antibiotic effect were in a concentration-dependent manner. However, delayed killing activity indicates colistin tolerance. Development of resistance after exposure was not detected except for the ATCC 19606 strain. Dosing suggestion based on the observations include administration of supplemental dose 3 MIU at 12 hours after loading dose, administration of maintenance dose 9 MIU in two divided doses and application of extended interval in renal adjustment dose. However, the information is applicable for non-colistin-heteroresistance A. baumannii with colistin MIC < 1.0 mg/L. As for heteroresistance and strain with colistin MIC > 1.0 mg/L, combination therapy would be the more appropriate treatment strategy.

Pathology and Host Immune Evasion During Human Leptospirosis: a Review.

Human leptospirosis is considered as one of the most widespread and potentially fatal zoonotic diseases that causes high mortality and morbidity in the endemic regions of tropical and subtropical countries. The infection can arise from direct or indirect exposure of human through contaminated environment that contains leptospires or animal reservoirs that carry leptospires. The clinical manifestations during human leptospirosis ranges from asymptomatic, mild infections to severe and life-threatening complications involving multi-organ failures with kidneys, lungs and liver severely affected. Despite much efforts have been put in to unravel the pathogenesis during human leptospirosis, it remains obscure to which extent the host factors or the pathogen itself contribute towards the pathogenesis. Host innate immunity, especially, polymorphonuclear neutrophils and complement system are involved in the first line of defense during human leptospirosis. However, pathogenic Leptospira has acquired diverse evasion strategies to evade from host immunity and establish infection in infected hosts. Hence, in this review, we focus on organs pathology during human leptospiral infection and host evasion strategies employed by Leptospira. A profound understanding on leptospiral immunity and how Leptospira subvert the immune system may provide new insights on the development of therapeutic regimens against this species in future.

Time-kill and post-antibiotic effect of colistin at different static concentrations in in vitro Acinetobacter baumannii

@# Nosocomial infection caused by Acinetobacter baumannii is common among immunocompromised patients. Treatment strategy is limited due to rapid resistance development and lack of novel antibiotic. Colistin has been the last line therapy with good in vitro activity against infections caused by multi-drug resistance A. baumannii. However, pharmacological updates are required to support dosing optimisation. This study aimed to determine the time-kill kinetic and resistance development after antibiotic exposure as well as post-antibiotic effect of colistin at different static concentrations in in vitro A. baumannii system. The static in vitro time-kill and post-antibiotic effect experiments were conducted against two clinical isolates as well as one reference isolate ATCC 19606. Time-kill and postantibiotic effect were studied at colistin concentrations ranging from 0.25MIC to 16.0MIC and 0.5MIC to 4.0MIC, respectively. Post-exposure resistance development was examined in time-kill study. Killing activity and post-antibiotic effect were in a concentration-dependent manner. However, delayed killing activity indicates colistin tolerance. Development of resistance after exposure was not detected except for the ATCC 19606 strain. Dosing suggestion based on the observations include administration of supplemental dose 3 MIU at 12 hours after loading dose, administration of maintenance dose 9 MIU in two divided doses and application of extended interval in renal adjustment dose. However, the information is applicable for non-colistin-heteroresistance A. baumannii with colistin MIC < 1.0 mg/L. As for heteroresistance and strain with colistin MIC > 1.0 mg/L, combination therapy would be the more appropriate treatment strategy.

Diagnosis and treatment of the cardiovascular consequences of Fabry disease.

Fabry disease (FD) has been a diagnostic challenge since it was first recognized in 1898, with patients traditionally suffering from considerable delay before a diagnosis is made. Cardiac involvement is the current leading cause of death in FD. A combination of improved enzyme assays, availability of genetic profiling, together with more organized clinical services for rare diseases, has led to a rapid growth in the prevalence of FD. The earlier and more frequent diagnosis of asymptomatic individuals before development of the phenotype has focussed attention on early detection of organ involvement and closer monitoring of disease progression. The high cost of enzyme replacement therapy at a time of constraint within many health economies, moreover, has challenged clinicians to target treatment effectively. This article provides an outline of FD for the general physician and summarizes the aetiology and pathology of FD, the cardiovascular consequences thereof, modalities used in diagnosis and then discusses current indications for treatment, including pharmacotherapy and device implantation.

Human leukocyte antigen (HLA) class II association in chronic hepatitis B patients with hepatocellular carcinoma in a Malay population: A pilot study.

Asian countries account for almost three quarter of hepatocellular carcinoma (HCC) reported globally and chronic hepatitis B infection is one of the main contributors. Clinical observations show that Malay patients with chronic hepatitis B and HCC tend to have a worse outcome, when compared to other two major races in Malaysia. The objectives of this study was to determine the frequency of human leukocyte antigen (HLA) class II alleles in chronic hepatitis B patients with HCC among Malays compared to the general population to identify potential associations of HLA alleles with this disease. HLA class II typing was performed in chronic hepatitis B patients with hepatocellular carcinoma (n=12) by -polymerase chain reaction, sequence specific primer (PCR-SSP) method. There were higher allelic frequencies of certain HLA-DQB1 and HLA-DRB1 alleles; HLA-DQB1*03 (07) (41.7%), and HLA-DRB1*12 (41.7% vs 28.6%) and compared to controls (41.7% vs 29.7%). However, there was no significant statistical correlation found when compared with the normal healthy general population. This study provides an insight into the HLA Class II association with chronic hepatitis B and hepatocellular carcinoma in Malays. However, findings from this study should be validated with a larger number of samples using a high resolution HLA typing.

Human leukocyte antigen (HLA) class II association in chronic hepatitis B patients with hepatocellular carcinoma in a Malay population: A pilot study

@#Asian countries account for almost three quarter of hepatocellular carcinoma (HCC) reported globally and chronic hepatitis B infection is one of the main contributors. Clinical observations show that Malay patients with chronic hepatitis B and HCC tend to have a worse outcome, when compared to other two major races in Malaysia. The objectives of this study was to determine the frequency of human leukocyte antigen (HLA) class II alleles in chronic hepatitis B patients with HCC among Malays compared to the general population to identify potential associations of HLA alleles with this disease. HLA class II typing was performed in chronic hepatitis B patients with hepatocellular carcinoma (n=12) by -polymerase chain reaction, sequence specific primer (PCR-SSP) method. There were higher allelic frequencies of certain HLA-DQB1 and HLA-DRB1 alleles; HLA-DQB1*03 (07) (41.7%), and HLA-DRB1*12 (41.7% vs 28.6%) and compared to controls (41.7% vs 29.7%). However, there was no significant statistical correlation found when compared with the normal healthy general population. This study provides an insight into the HLA Class II association with chronic hepatitis B and hepatocellular carcinoma in Malays. However, findings from this study should be validated with a larger number of samples using a high resolution HLA typing.

Group B streptococcus infection in a sudden unexpected death of infancy - the importance of microbiological investigation at post-mortem.

Group B streptococcus (GBS) is a common cause of infection in newborns and in early infants. However, GBS infection in an infant older than three months is infrequently reported in the literature. We reported a case of an apparently well six-month-old infant who died of sudden death due to GBS pneumonia, diagnosed at autopsy. The six-month-old, apparently well male infant was brought in dead to the Emergency Department. He underwent medicolegal autopsy four hours after death, as part of an overall sudden unexpected death in infancy investigation (SUDI). Apart from whitish froth oozing out of both nostrils, he appeared to be well-nourished infant without any deformity, syndromic features or obvious suspicious marks of injury externally. Internal examination showed generalized hyperinflated with patchy consolidation of upper and middle lobes of bilateral lung. Multiple matted mesenteric lymphadenopathy were also detected. Blood and lung tissue specimens collected under aseptic technique yielded growth of GBS. Post-mortem histology from consolidated lungs confirmed pneumonic features while mesenteric lymph nodes showed reactive changes inkeeping with underlying infective process. Death was attributed to GBS pneumonia. This case highlights the importance of a detailed autopsy in sudden unexpected death in infancy (SUDI) and the crucial role of post-mortem microbiological study in such cases. Relevant autopsy protocols that need to be employed during microbiological sampling are briefly discussed.

Group B streptococcus infection in a sudden unexpected death of infancy – the importance of microbiological investigation at post-mortem

@#Group B streptococcus (GBS) is a common cause of infection in newborns and in early infants. However, GBS infection in an infant older than three months is infrequently reported in the literature. We reported a case of an apparently well six-month-old infant who died of sudden death due to GBS pneumonia, diagnosed at autopsy. The six-month-old, apparently well male infant was brought in dead to the Emergency Department. He underwent medicolegal autopsy four hours after death, as part of an overall sudden unexpected death in infancy investigation (SUDI). Apart from whitish froth oozing out of both nostrils, he appeared to be well-nourished infant without any deformity, syndromic features or obvious suspicious marks of injury externally. Internal examination showed generalized hyperinflated with patchy consolidation of upper and middle lobes of bilateral lung. Multiple matted mesenteric lymphadenopathy were also detected. Blood and lung tissue specimens collected under aseptic technique yielded growth of GBS. Post-mortem histology from consolidated lungs confirmed pneumonic features while mesenteric lymph nodes showed reactive changes inkeeping with underlying infective process. Death was attributed to GBS pneumonia. This case highlights the importance of a detailed autopsy in sudden unexpected death in infancy (SUDI) and the crucial role of post-mortem microbiological study in such cases. Relevant autopsy protocols that need to be employed during microbiological sampling are briefly discussed.

Colistin-associated nephrotoxicity among patients in intensive care units (ICU) of hospitals in Selangor.

INTRODUCTION: The increasing trend of extensively drugresistant gram negative bacteria responsible for nosocomial infections has prompted resurgence colistin usage. Colistin-induced nephrotoxicity is a concern with disparity in the reported rates between previous studies. This study aims to evaluate colistin-induced nephrotoxicity among Malaysian population. METHODS: The medical records of ICU patients receiving colistin therapy in Hospital Serdang and Hospital Sungai Buloh from 2010 to 2012 were retrospectively reviewed. Demographics data, treatment characteristic as well as culture result and creatinine level were documented. Nephrotoxicity was determined based on RIFLE criteria. RESULTS: A total of 100 patients were included. Median daily dose, cumulative dose and duration of colistin therapy were 3.0 MIU (IQR: 4, range 1-12), 17.8 MIU (IQR: 31.5, range 2-180) and seven days (IQR: 4, range 1-30). Nephrotoxicity was found in 23% of the study population. All cases were reversible but marginally associated with higher mortality. No statistical association exist between age, gender and race as well as administration routes with nephrotoxicity by univariable analysis. The association of dose and duration with nephrotoxicity was also not significant by univariable analysis. After adjustment for confounders, statistical association between the independent variables and dependent variable remains not significant. CONCLUSION: Lower dose and shorter duration in local settings contribute to lack of association between colistin therapy and nephrotoxicity in this study. Higher dosing regimen with loading dose application has been introduced in the latest National Antibiotic Guideline. Further evaluation of colistin-induced nephrotoxicity and potential risk factors is therefore warranted.

Presence of methicillin resistance and heteroresistance among Coagulase Negative Staphylococci (CoNS) isolates obtained from Health Sciences students at a Public University.

This study was carried out to investigate the Coagulase Negative Staphylococci (CoNS) nasal carriage and the presence of methicillin resistant Coagulase Negative Staphylococci (MR-CoNS) among health sciences students at Faculty of Medicine and Health Sciences, Universiti Putra Malaysia. A total of 120 isolates of CoNS (62.5%) was isolated from 192 student volunteers. The mecA gene was detected in 15 isolates of CoNS (12.5%). Eight out of the 15 isolates of mecA positive CoNS were resistant to cefoxitin in disc diffusion test whereas the remaining seven isolates of mecA positive CoNS were susceptible to cefoxitin. Analysis of questionnaires showed no significant association between CoNS nasal carriage and the socio-demographic and risk factors except for the genders and history of cold (P < 0.050). Generally, this finding showed a relatively low level of methicillin resistance among CoNS nasal carriage from student volunteers.

Chloroanisoles may explain mold odor and represent a major indoor environment problem in Sweden.

Indoor mold odor is associated with adverse health effects, but the microbial volatiles underlying mold odor are poorly described. Here, chloroanisoles were studied as potential key players, being formed by microbial metabolism of chlorophenols in wood preservatives. Using a three-stage approach, we (i) investigated the occurrence of chloroanisoles in buildings with indoor air quality problems, (ii) estimated their frequency in Sweden, and (iii) evaluated the toxicological risk of observed chloroanisole concentrations. Analyses of 499 building materials revealed several chloroanisole congeners in various types of buildings from the 1950s to 1970s. Evaluation of Swedish records from this time period revealed three coinciding factors, namely an unprecedented nationwide building boom, national regulations promoting wood preservatives instead of moisture prevention, and use of chlorophenols in these preservatives. Chlorophenols were banned in 1978, yet analysis of 457 indoor air samples revealed several chloroanisole congeners, but at median air levels generally below 15 ng/m(3) . Our toxicological evaluation suggests that these concentrations are not detrimental to human health per se, but sufficiently high to cause malodor. Thereby, one may speculate that chloroanisoles in buildings contribute to adverse health effects by evoking odor which, enhanced by belief of the exposure being hazardous, induces stress-related and inflammatory symptoms.

Transgene expression in tick cells using Agrobacterium tumefaciens.

Ticks transmit infectious agents to humans and other animals. Genetic manipulation of vectors like ticks could enhance the development of alternative disease control strategies. Transgene expression using the phytopathogen Agrobacterium tumefaciens has been shown to promote the genetic modification of non-plant cells. In the present work we developed T-DNA constructs for A. tumefaciens to mediate transgene expression in HeLa cells as well as Rhipicephalus microplus tick cells. Translational fusions eGfp:eGfp or Salp15:eGfp, including the enhanced-green fluorescent protein and the Ixodes scapularis salivary factor SALP15 genes, were constructed using the CaMV 35S (cauliflower mosaic virus) promoter, "PBm" tick promoter (R. microplus pyrethroid metabolizing esterase gene) or the Simian Virus SV40 promoter. Confocal microscopy, RT-PCR and Western-blot assays demonstrated transgene(s) expression in both cell lines. Transgene expression was also achieved in vivo, in both R. microplus and I. scapularis larvae utilizing a soaking method including the A. tumefaciens donor cells and confirmed by nested-RT-PCR showing eGfp or Salp15 poly-A-mRNA(s). This strategy opens up a new avenue to express exogenous genes in ticks and represents a potential breakthrough for the study of tick-host pathophysiology.