scholarly journals Investigation of polymorphisms in the P. falciparum artemisinin resistance marker kelch13 in asymptomatic infections in a rural area of Cameroon

2017 ◽  
Author(s):  
Innocent Safeukui ◽  
Jerome Fru-Cho ◽  
Alassane Mbengue ◽  
Niraja Suresh ◽  
Dieudonne L. Njimoh ◽  
...  
Keyword(s):  
Plasma Levels ◽  
Central Africa ◽  
Artemisinin Resistance ◽  
Cross Sectional Study ◽  
Asymptomatic Infection ◽  
Cross Sectional ◽  
Single Nucleotide ◽  
Molecular Surveillance ◽  
Polymerase Chain ◽  
Asymptomatic Infections

AbstractBackgroundThe genetic variability of the artemisinin resistance (AR) molecular marker kelch13 (k13) has been extensively investigated in Plasmodium falciparum malaria parasites from symptomatic infections in South East (SE) Asia where AR is highly prevalent, as well as in Africa where evidence of AR has emerged only recently. However, molecular surveillance and risk of transmission of AR also require monitoring asymptomatic infection. Here, molecular analyses were used to investigate polymorphisms in k13 and their potential for transmission in asymptomatic adults in Bolifamba, Cameroon in Central Africa.MethodsUsing polymerase chain reaction (PCR), we amplified and sequenced the full length of k13 from P. falciparum infections detected in the blood of 33 asymptomatic adults (age: 18-55 years-old) collected in a cross-sectional study from July 2008 to October 2009. Risk of increased transmission was assessed by quantifying gametocytes by qPCR. Quantitative ELISA was used to detect plasma levels of PfHRP2 to establish total parasite burdens associated with asymptomatic infection.ResultsOut of 33 isolates tested, 14 (42.4%) presented at least one single nucleotide polymorphism (SNP) in k13. Five non-synonymous SNPs were detected (K189T/N, N217H, R393K and E433K). None were located in the ß-propeller domain, where AR mutations have been detected in both SE Asian and, more recently, African parasites. K189T/N and N217H have been previously reported in African strains, but R393K and E433K are new polymorphisms. Gametocytes were detected in 24.2% of infections, without significant association with detected k13 polymorphisms. Notably, polymorphisms outside of the ß-propeller domain detected in k13 were associated with a significant increase of PfHRP2 plasma levels but not circulating parasite levels detected by qPCR.ConclusionsThis study provides the baseline prevalence of k13 polymorphisms in asymptomatic infection for molecular surveillance in tracking AR. Unexpectedly, it also suggests association of k13 polymorphisms outside of the ß-propeller domain with total P. falciparum burden in asymptomatic infection, that needs to be validated in future studies.

scholarly journals Identifying asymptomatic infections of visceral leishmaniasis in non-endemic regions with the associated risk factors in Gedaref state, Sudan

2019 ◽  
Author(s):  
Nouh Saad Mohamed ◽  
Hussam A. Osman ◽  
Mohamed S. Muneer ◽  
Abdallah M. Samy ◽  
Ayman Ahmed ◽  
...  
Keyword(s):  
Risk Factors ◽  
Visceral Leishmaniasis ◽  
Detection Method ◽  
Cross Sectional Study ◽  
Asymptomatic Infection ◽  
Cross Sectional ◽  
Asymptomatic Infections ◽  
Associated Risk Factors ◽  
Study Participants ◽  
Planted Tree

Abstract Objectives Visceral Leishmaniasis (VL) can be symptomatic and asymptomatic infection. In this study we aimed at investigating the prevalence of asymptomatic infections and to study risk factors of VL in non-endemic regions in Gedaref state, Sudan. A descriptive cross-sectional study conducted during 2014. Blood samples were collected to serological and molecular analysis. Sticky traps, knockdown spray and CDC miniature light traps were used for the collection of sandflies. Results Ninety-Five participants were included; 52 from Abukishma, 15 Algadamblia Tirfa, 25 Abualnaja and 3 were from Algadamblia Aljabal. Most of the study participants were belonging to the Belala tribe (74.3%). The most frequent reported age was above 40-years old (9.5%). Females were (61.1%) and males were (38.9%). B. aeygptica was the most planted tree in/around the houses (46.3%). 73 (76.8%) of the participants bred more than two types of animals in the house. DAT test revealed 5 positive participants (5.2%). 4/5 DAT positive were past VL infection. PCR detected 35 (36.8%) positive patients. A total of 31 (32.6%) were considered asymptomatic infections based on PCR detection method. Households planted Balanites/Acacia trees or breed domestic animals were found in high percentages with VL PCR positive participants (60.1%, 91.4%).

scholarly journals Severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection among hospital workers in a severely affected institution in Madrid, Spain: A surveillance cross-sectional study

2020 ◽  
pp. 1-7
Author(s):  
Felipe Pérez-García ◽  
Aurora Pérez-Zapata ◽  
Naroa Arcos ◽  
Manuel De la Mata ◽  
María Ortiz ◽  
...  
Keyword(s):  
Multivariate Logistic Regression Analysis ◽  
Cross Sectional Study ◽  
Sectional Study ◽  
Cross Sectional ◽  
Previous Contact ◽  
Polymerase Chain ◽  
Asymptomatic Infections ◽  
Secondary Hospital ◽  
Respiratory Coronavirus ◽  
The Impact

Abstract Objective: To analyze the impact of the coronavirus disease 2019 (COVID-19) pandemic in workers of a hospital located in one of the most affected areas in Spain. Design, settings, and patients: Cross-sectional study performed between March and May 2020 over all workers of a secondary hospital in Madrid, Spain. Methods: We employed polymerase chain reaction (PCR, for symptomatic individuals) and serology (for both PCR-negative symptomatic workers and asymptomatic workers) as diagnostic tests for severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We analyzed the prevalence of the virus in healthcare workers (HCWs) and nonhealthcare workers (nHCWs). We also collected information about the use of personal protective equipment (PPEs) and possible contacts prior to infection. Results: In total, 2,963 workers were included: 1,092 were symptomatic, and of these, 539 were positive by PCR (49.4% of symptomatic workers). From the remaining symptomatic workers, 197 (35.6%) were positive by serology. Regarding asymptomatic workers, 345 were positive by serology (31.9% of infected workers). In total, 1,081 (36.5%) presented a positive diagnostic test for SARS-CoV-2. Infection rates were different between HCWs (37.4%) and nHCWs (29.8%) (P = .006). In the multivariate logistic regression analysis, the use of PPE (protective: OR, 0.56; 95% CI, 0.44–0.72; P < .001) and previous contact with COVID-19 patients (risk factor: OR, 1.69; 95% CI, 1.28–2.24; P < .001) were independent factors that were associated with SAS-CoV-2 infection. Conclusions: Overall, >36% of our workers became infected with SARS-CoV-2, and the rate of asymptomatic infections accounted for almost 32% of all SARS-CoV-2 infections. We detected differences in the rates of infection between HCWs and nHCWs. The use of PPE and previous contact with COVID-19 patients were associated with SARS-CoV-2 infection.

Lack of Association between Eotaxin-1 Gene Polymorphisms and Nasal Polyposis

2011 ◽  
Vol 145 (6) ◽  
pp. 1036-1039 ◽  
Author(s):  
Suna Ekinci ◽  
Selim S. Erbek ◽  
Erkan Yurtcu ◽  
Feride I. Sahin
Keyword(s):  
Single Nucleotide Polymorphisms ◽  
Gene Polymorphisms ◽  
Nasal Polyposis ◽  
Cross Sectional Study ◽  
Nucleotide Polymorphisms ◽  
Cross Sectional ◽  
Single Nucleotide ◽  
Association Coefficient ◽  
Tertiary Referral Center ◽  
Polymerase Chain

Objective. To examine whether there is an association of eotaxin-1 gene polymorphisms with nasal polyposis (NP). Study Design. Cross-sectional study. Setting. Tertiary referral center. Subjects and Methods. The study group included 85 patients with NP and 93 controls without sinonasal disease. Genotypes of eotaxin-1 (−384 A>G and +67 G>A) were identified by restriction fragment length polymorphism analyses after polymerase chain reaction. Results. The −384 A>G and +67 G>A single nucleotide polymorphisms were higher in patients with NP than in controls ( P = .044 and P = .019, respectively). However, their relation was statistically poor (association coefficient = 0.18). Consistent with this result, comparisons of allele frequencies for both single nucleotide polymorphisms were not significantly different (−384 A>G, P = .164; +67 G>A, P = .144). Conclusion. In this study, eotaxin-1 −384 A>G or 67 G>A genotypes were not associated with susceptibility to NP.

Asymptomatic low-density Plasmodium infection during non-transmission season: a community-based cross-sectional study in two districts of North Eastern Region, India

2021 ◽  
Author(s):  
Hari Shankar ◽  
Sobhan Phookan ◽  
Mrigendra Pal Singh ◽  
Ram Suresh Bharti ◽  
Naseem Ahmed ◽  
...  
Keyword(s):  
Cross Sectional Study ◽  
Diagnostic Tools ◽  
Eastern Region ◽  
Low Density ◽  
Plasmodium Infection ◽  
Sectional Study ◽  
Cross Sectional ◽  
Health Agencies ◽  
North Eastern ◽  
Asymptomatic Infections

Abstract Background Malaria elimination requires targeting asymptomatic and low-density Plasmodium infections that largely remain undetected. Therefore we conducted a cross-sectional study to estimate the burden of asymptomatic and low-density Plasmodium infection using conventional and molecular diagnostics. Methods A total of 9118 participants, irrespective of age and sex, were screened for malaria using rapid diagnostic tests (RDTs), microscopy and polymerase chain reaction. Results Among the participants, 707 presented with symptoms and 8411 without symptoms, of which Plasmodium was present in 15.6% (110/707) and 8.1% (681/8411), respectively. Low-density infection was found in 5.1% (145/2818) of participants and 8327 of 9118 were Plasmodium negative. Endemicity was propotional to asymptomatic infections (high endemicity 11.1% [404/3633] vs low endemicity 5.8% [277/4778]; odds ratio [OR] 2.0 [95% confidence interval {CI} 1.7 to 2.4]) but inversely related to low-density infection (high endemicity 3.7% [57/1545] vs low endemicity 6.9% [88/1273]; OR 1.9 [95% CI 1.4 to 2.7]). The spleen rate in children 2–9 y of age was 17.9% (602/3368) and the enlarged spleen index was 1.6. Children between 8 and 14 y showed higher odds for asymptomatic (adjusted OR [aOR] 1.75 [95% CI 1.4 to 2.2]) and low-density infections (aOR 0.63 [95% CI 0.4 to 1.0)] than adults. Conclusions The prevalence of asymptomatic and low-density Plasmodium infection undermines the usefulness of standard diagnostic tools used by health agencies. This necessitates deploying molecular tools in areas where malaria microscopy/RDTs indicate a dearth of infection.

scholarly journals 425. The Utility of Paired Upper and Lower COVID-19 Sampling in Patients with Artificial Airways

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S279-S279
Author(s):  
Eimear Kitt ◽  
Julia S Sammons ◽  
Kathleen Chiotos ◽  
Susan E Coffin ◽  
Susan E Coffin ◽  
...  
Keyword(s):  
Respiratory Tract ◽  
Lower Respiratory Tract ◽  
Diagnostic Testing ◽  
Cross Sectional Study ◽  
Upper Respiratory Tract ◽  
Cross Sectional ◽  
Mechanically Ventilated ◽  
Paired Samples ◽  
Control And Prevention ◽  
Polymerase Chain

Abstract Background The Centers for Disease Control and Prevention (CDC) recommends upper respiratory tract (URT) polymerase chain reaction (PCR) testing as the initial diagnostic test for Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Lower respiratory tract (LRT) testing for patients requiring mechanical ventilation is also recommended. The goal of this study was to evaluate concordance between paired URT and LRT specimens in children undergoing pre-admission/procedure screening or diagnostic testing. We hypothesized that &lt; 10% of paired tests would have discordant results. Methods Single center cross-sectional study including children with artificial airways who had paired URT and LRT SARS-CoV-2 PCR testing between 4/1/2020 and 6/8/2020. URT specimens included nasopharyngeal (NP) swabs and aspirates. LRT specimens included tracheal aspirates and bronchoalveolar lavages. URT and LRT specimens were classified as paired if the two specimens were collected within 24 hours. Artificial airways included tracheostomies and endotracheal tubes. Tests were classified as diagnostic versus screening based on the indication selected in the order. Results 102 paired specimens were obtained during the study period. Fifty-nine were performed for screening and 43 were performed for diagnosis of suspected SARS-CoV-2. Overall, 94 specimens (92%) were concordant, including 89 negative from both sources and 5 positive from both sources. Eight specimens (8%) were discordant, all of which were positive from the URT and negative from the LRT (Figure 1). Among patients undergoing screening, 3 of 4 positive tests were discordant and among symptomatic patients, 5 of 9 positive tests were discordant. There were no instances of a positive LRT specimen with a negative URT specimen. Figure 1. Performance of upper and lower respiratory tract SARS-CoV-2 PCR testing in children with artificial airways Conclusion Overall, most paired samples from the URT and LRT yielded concordant results with no pairs positive from the LRT and negative from the URT. These data support the CDC recommendation that URT specimens are the preferred initial SARS-CoV-2 test, while LRT specimens should be collected only from mechanically ventilated with suspected SARS-CoV-2. Disclosures All Authors: No reported disclosures

scholarly journals Genetic Variants in Smoking-Related Genes in Two Smoking Cessation Programs: A Cross-Sectional Study

2021 ◽  
Vol 18 (12) ◽  
pp. 6597
Author(s):  
Gloria Pérez-Rubio ◽  
Luis Alberto López-Flores ◽  
Ana Paula Cupertino ◽  
Francisco Cartujano-Barrera ◽  
Luz Myriam Reynales-Shigematsu ◽  
...  
Keyword(s):  
Smoking Cessation ◽  
Cross Sectional Study ◽  
Nucleotide Polymorphisms ◽  
Sectional Study ◽  
Cross Sectional ◽  
Single Nucleotide ◽  
Genotype Frequencies ◽  
Quitting Smoking ◽  
Genes Encoding ◽  
Genomic Regions

Previous studies have identified variants in genes encoding proteins associated with the degree of addiction, smoking onset, and cessation. We aimed to describe thirty-one single nucleotide polymorphisms (SNPs) in seven candidate genomic regions spanning six genes associated with tobacco-smoking in a cross-sectional study from two different interventions for quitting smoking: (1) thirty-eight smokers were recruited via multimedia to participate in e-Decídete! program (e-Dec) and (2) ninety-four attended an institutional smoking cessation program on-site. SNPs genotyping was done by real-time PCR using TaqMan probes. The analysis of alleles and genotypes was carried out using the EpiInfo v7. on-site subjects had more years smoking and tobacco index than e-Dec smokers (p < 0.05, both); in CYP2A6 we found differences in the rs28399433 (p < 0.01), the e-Dec group had a higher frequency of TT genotype (0.78 vs. 0.35), and TG genotype frequency was higher in the on-site group (0.63 vs. 0.18), same as GG genotype (0.03 vs. 0.02). Moreover, three SNPs in NRXN1, two in CHRNA3, and two in CHRNA5 had differences in genotype frequencies (p < 0.01). Cigarettes per day were different (p < 0.05) in the metabolizer classification by CYP2A6 alleles. In conclusion, subjects attending a mobile smoking cessation intervention smoked fewer cigarettes per day, by fewer years, and by fewer cumulative pack-years. There were differences in the genotype frequencies of SNPs in genes related to nicotine metabolism and nicotine dependence. Slow metabolizers smoked more cigarettes per day than intermediate and normal metabolizers.

West Nile Virus Chorioretinitis in the Presence of Negative Cerebrospinal Fluid Polymerase Chain Reaction Results

2021 ◽  
pp. 247412642097925
Author(s):  
Kareem Moussa ◽  
Karen W. Jeng-Miller ◽  
Leo A. Kim ◽  
Dean Eliott
Keyword(s):  
Cerebrospinal Fluid ◽  
West Nile Virus ◽  
Cross Sectional Study ◽  
Nucleic Acid Amplification ◽  
Sectional Study ◽  
Chain Reaction ◽  
West Nile ◽  
Cross Sectional ◽  
Positive Serum ◽  
Polymerase Chain

Purpose: This work aims to evaluate the utility of nucleic acid amplification testing (NAAT) and serology in confirming West Nile Virus (WNV) infection in patients with suspected WNV chorioretinitis. Methods: A retrospective cross-sectional study was conducted of a cluster of patients who presented to the Retina Service of Massachusetts Eye and Ear between September and October 2018. Results: Three patients were identified with classic WNV chorioretinitis lesions with negative cerebrospinal fluid NAAT and positive serum serology findings. The diagnosis of WNV chorioretinitis was made based on the appearance of the fundus lesions and the presence of characteristic findings on fluorescein angiography as previously described in the literature. Conclusions: This report highlights 3 unique cases of WNV chorioretinitis in which NAAT of cerebrospinal fluid failed to identify WNV as the inciting agent. These cases stress the importance of serum serologic testing in diagnosing WNV infection.

scholarly journals Lack of HPV in pterygium with no evidence of autoinoculation and the role of cytokines in pterygium with dry eye

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lita Uthaithammarat ◽  
Ngamjit Kasetsuwan ◽  
Yuda Chongpison ◽  
Pimpetch Kasetsuwan ◽  
Usanee Reinprayoon ◽  
...  
Keyword(s):  
Dry Eye ◽  
Hpv Infection ◽  
Cross Sectional Study ◽  
Urine Samples ◽  
Vascular Endothelial ◽  
Cross Sectional ◽  
Hpv Dna ◽  
Polymerase Chain ◽  
Endothelial Growth Factor

AbstractThis study evaluated human papillomavirus’s (HPV) role in pterygium pathogenesis, its autoinoculation from genitalia to ocular surface, potential cytokines involved, and crosstalk cytokines between pterygium and dry eye (DE). This cross-sectional study enrolled 25 healthy controls (HCs) and 116 pterygium patients. Four subgroups of pterygium and DE were used in cytokine evaluations. Conjunctival and pterygium swabs and first-void urine samples (i.e., genitalia samples) were collected for HPV DNA detection using real-time polymerase chain reaction. Tear cytokines interleukin (IL)-6, IL-18, and vascular endothelial growth factor (VEGF) in tears were evaluated. No HPV DNA was detected in conjunctival or pterygium swabs. No association was found between HPV DNA in urine samples and that from conjunctival or pterygium swabs. Tear VEGF levels were significantly higher in pterygium patients than in HCs, with no markedly different levels between primary and recurrent pterygia. Tear IL-6, IL-18, and tear VEGF were significantly higher in participants with DE, regardless of pterygium status. In conclusion, HPV infection was not a pathogenic factor of pterygia. The hypothesis of HPV transmitting from the genitals to ocular surfaces was nullified. Tear VEGF was involved in both pterygia and DE, whereas tear IL-6 and IL-18 played roles only in DE.

scholarly journals Kondisi Kebersihan Lingkungan Berhubungan dengan Risiko Penularan Kasus Leptospirosis di Area Pasar Tradisional

2020 ◽  
pp. 199-208
Author(s):  
Dyah Widiastuti ◽  
Dwi Priyanto
Keyword(s):  
Cross Sectional Study ◽  
Market Area ◽  
Chi Square ◽  
Pathogenic Leptospira ◽  
Cross Sectional ◽  
Chi Square Test ◽  
History Of ◽  
Polymerase Chain ◽  
Gathering Place ◽  
The Relationship

Leptospirosis is associated with occupations which exposed workers to contaminated environments. The risk of leptospirosis exposure in the market as a gathering place for many people needs to be assessed, to obtain the basis for decision making to anticipate leptospirosis transmission. This study aimed to determine the relationship between market environmental conditions including market sanitation conditions, the level of rat density and the presence of leptospira-positive rats  toward the history of leptospirosis exposure among market workers (traders and janitors). A cross sectional study conducted in 35 markets in Banjarnegara and 175 market workers randomly selected. Blood samples analysed using ELISA against 40 Kda pathogenic Leptospira protein. Rat trapping  conducted in each market for two days with 100 traps. The caught mice examined with Polymerase Chain Reaction (PCR) to detect the presence of Leptospira bacteria in their kidneys. Leptospirosis exposure was spread in 17 markets in Banjarnegara. The PCR examination showed that the pathogenic Leptospira infected rats were spread in four markets in Banjarnegara. Chi square test showed that the hygene condition in market area was significantly associated with the leptospirosis exposure. Markets workers (traders and janitors) were at risk for leptospirosis proved by high seroprevalence of leptospirosis in this study.

scholarly journals Circulating Levels of MicroRNAs Associated With Hypertension: A Cross-Sectional Study in Male and Female South African Participants

2021 ◽  
Vol 12 ◽  
Author(s):  
Don M. Matshazi ◽  
Cecil J. Weale ◽  
Rajiv T. Erasmus ◽  
Andre P. Kengne ◽  
Saarah F. G. Davids ◽  
...  
Keyword(s):  
South African ◽  
Expression Profiles ◽  
Cross Sectional Study ◽  
Therapeutic Interventions ◽  
Hypertension Status ◽  
Cross Sectional ◽  
Progression Of Disease ◽  
Polymerase Chain ◽  
Circulating Levels ◽  
Diagnosis Of Hypertension

MicroRNAs are non-coding, post-transcriptional regulators of gene expression and their dysregulation has been associated with development of various diseases, including hypertension. Consequently, understanding their role in the pathogenesis and progression of disease is essential. Prior research focusing on microRNAs in disease has provided a basis for understanding disease prognosis and offered possible channels for therapeutic interventions. Herein, we aimed to investigate possible differences in the expression profiles of five microRNAs in the blood of participants grouped on the basis of their hypertension status. This was done to elucidate the possible roles played by these microRNAs in the development of hypertension. Using quantitative reverse transcription polymerase chain reaction, we evaluated the expression levels of miR-126-3p, 30a-5p, 182-5p, 30e-3p, and 1299 in the whole blood of 1456 participants, normotensive (n = 573), screen-detected hypertensive (n = 304) and known hypertensive (n = 579). The expression of miR-126-3p and 182-5p was significantly higher in known hypertensives relative to both screen-detected hypertensives and normotensives, and also in screen-detected hypertensives vs normotensives. A significant association between the expression of miR-126-3p, 182-5p, and 30a-5p and known hypertension was also evident. This study demonstrated dysregulated miR-126-3p, 182-5p, and 30a-5p expression in hypertension, highlighting the possible efficacy of these microRNAs as targets for the diagnosis of hypertension as well as the development of microRNA-based therapies.

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