The occurrence of Ebola virus (EBOV) in West Africa during 2013–2015 is unprecedented. Early reports suggested that in this outbreak EBOV is mutating twice as fast as previously observed, which ...indicates the potential for changes in transmissibility and virulence and could render current molecular diagnostics and countermeasures ineffective. We have determined additional full-length sequences from two clusters of imported EBOV infections into Mali, and we show that the nucleotide substitution rate (9.6 × 10–4 substitutions per site per year) is consistent with rates observed in Central African outbreaks. In addition, overall variation among all genotypes observed remains low. Thus, our data indicate that EBOV is not undergoing rapid evolution in humans during the current outbreak. This finding has important implications for outbreak response and public health decisions and should alleviate several previously raised concerns.
2D flow simulation in compact deterministic ratchets show asymmetric flow lane distribution, which implies a new type of particle motion.
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► Mixed motion observed in deterministic ...ratchets. ► Asymmetric flow lane distributions found with simulations. ► Anisotropy of permeability to is the cause of mixed motion.
Nowadays microfluidic devices are becoming popular for cell/DNA sorting and fractionation. One class of these devices, namely deterministic ratchets, seems most promising for continuous fractionation applications of suspensions (Kulrattanarak et al., 2008
1). Next to the two main types of particle behavior, zigzag and displacement motion as noted by the inventors (Huang et al., 2004
2) and (Inglis et al., 2006
3), we have shown recently the existence of a intermediate particle behavior, which we named ‘mixed motion’. In this paper we formulate the hypothesis that the occurrence of mixed motion is correlated with anisotropy in the permeability of the obstacle array. This hypothesis we base on the comparison of experimental observations of mixed motion and the flow lane distribution as obtained from 2-D flow simulations.
The external quality assessment (EQA) or external quality control is an evaluation conducted by a certified external organization to inquire about the quality of the results provided by a laboratory. ...The primary role of EQA is to verify the accuracy of laboratory results. This is essential in research because research data should be published in international peer-reviewed journals, and laboratory results must be repeatable. In 2007, the University Clinical Research Center (UCRC's) biosafety level 3 (BSL-3) laboratory joined the EQA program with the College of American Pathologists in acid-fast staining and culture and identification of mycobacteria as per laboratory accreditation preparedness. Thus, after 11 years of participation, the goal of our study was to evaluate the performance of our laboratory during the different interlaboratory surveys.
We conducted a descriptive retrospective study to evaluate the results of UCRC mycobacteriology laboratory from surveys conducted during 2007 and 2017.
Of the 22 evaluations, the laboratory had satisfactory (100% of concordance results) in 18 (81.8%) and good (80% of concordance results) in 4 (18.2%). Overall, the laboratory was above the commended/accepted limits of 75%.
So far, UCRC's BSL-3 performed well during the first 11 years of survey participation, and efforts should be deployed to maintain this high quality in the preparedness for laboratory accreditation and support to clinical trials.
Please cite this paper as: Salihu H, August E, Salemi J, Weldeselasse H, Sarro Y, Alio A. The association between female genital mutilation and intimate partner violence. BJOG 2012;119:1597–1605.
...Objective To determine whether female genital mutilation (FGM) is a risk factor for intimate partner violence (IPV) and its subtypes (physical, sexual and emotional).
Design Population‐based cross‐sectional study.
Setting The study used the 2006 Demographic and Health Survey (DHS) conducted in Mali.
Population A total of 7875 women aged 15–49 years who responded to the domestic violence and female circumcision modules in the 2006 administration of the DHS in Mali.
Methods Multivariable logistic regression was used to compute adjusted odds ratios (aOR) and 95% confidence intervals (CI) to measure risk for IPV.
Main outcome measures The outcomes of interest were IPV and its subtypes.
Results Women with FGM were at heightened odds of IPV (aOR 2.71, 95% CI 2.17–3.38) and IPV subtypes: physical (aOR 2.85, 95% CI 2.22–3.66), sexual (aOR 3.24, 95% CI 1.80–5.82), and emotional (aOR 2.28, 95% CI 1.68–3.11). The odds of IPV increased with ascending FGM severity (P for trend <0.0001). The most elevated odds were observed among women with severe FGM, who were nearly nine times as likely to experience more than one IPV subtype (aOR 8.81, 95% CI 5.87–13.24).
Conclusions Study findings underscore the need for multi‐tiered strategies, incorporating policy and education, to reduce FGM and IPV, potentially improving the holistic health and wellbeing of Malian women.
Although Drug resistance tuberculosis is not a new phenomenon, Mali remains one of the "blank" countries without systematic data.
Between 2006 and 2014, we enrolled pulmonary TB patients from local ...TB diagnostics centers and a university referral hospital in several observational cohort studies. These consecutive patients had first line drug susceptibility testing (DST) performed on their isolates. A subset of MDR was subsequently tested for second line drug resistance.
A total of 1186 mycobacterial cultures were performed on samples from 522 patients, including 1105 sputa and 81 blood samples, yielding one or more Mycobacterium tuberculosis complex (Mtbc) positive cultures for 343 patients. Phenotypic DST was performed on 337 (98.3%) unique Mtbc isolates, of which 127 (37.7%) were resistant to at least one drug, including 75 (22.3%) with multidrug resistance (MDR). The overall prevalence of MDR-TB was 3.4% among new patients and 66.3% among retreatment patients. Second line DST was available for 38 (50.7%) of MDR patients and seven (18.4%) had resistance to either fluoroquinolones or second-line injectable drugs.
The drug resistance levels, including MDR, found in this study are relatively high, likely related to the selected referral population. While worrisome, the numbers remained stable over the study period. These findings prompt a nationwide drug resistance survey, as well as continuous surveillance of all retreatment patients, which will provide more accurate results on countrywide drug resistance rates and ensure that MDR patients access appropriate second line treatment.
In Mali early detection and treatment of multidrug-resistant tuberculosis (MDR-TB) are still challenging due to the cost, time and/or complexity associated with regular tests. Microscopic Observation ...Drug Susceptibility (MODS) is a low-cost assay validated by WHO in 2010. It is a liquid-culture-based assay to detect the ‘cording’ characteristic of Mycobacterium tuberculosis complex and to assess susceptibility to both isoniazid and rifampicin defining multidrug-resistant tuberculosis (MDR-TB). In this study we aimed to evaluate the performance of MODS as diagnostic tool compared with a validated method—Mycobacteria Growth Indicator Tube/Antimicrobial Susceptibility Testing/Streptomycin, Isoniazid, Rifampicin and Ethambutol (MGIT/AST/SIRE).
Between January 2010 and October 2015 we included 98 patients with suspected TB in an observational cohort study. The sensitivity and specificity of MODS assay for detecting TB were respectively 94.12% and 85.71% compared with the reference MGIT/7H11 culture, with a Cohen κ coefficient of 0.78 (95% CI 0.517–1.043). The median time to culture positivity for MODS assay and MGIT (plus interquartile range, IQR) was respectively 8 days (IQR 5–11) and 6 days (IQR 5–6). In detecting patients with MDR-TB, the sensitivity and specificity of MODS assay were respectively 100% and 95.92%. The positive predictive value and negative predictive value were, respectively, 66.7% and 100%. The median turnaround times for obtaining MDR-TB results using MODS assay and MGIT/AST/SIRE was respectively 9 days and 35 days. Hence, the MODS assay rapidly identifies MDR-TB in Mali compared with the MGIT/AST/SIRE.
As an easy, simple, fast and affordable method, the MODS assay could significantly improve the management of TB.
The sensitive analysis of proteins is central to disease diagnosis. The detection and investigation of angiogenic and inflammatory ligands in the tumor tissue can further improve the level of ...knowledge of the cancer disease by capturing the heterogeneity and the complexity of the tumor microenvironment. In previous works, we demonstrated that high-quality silicon nanowire field-effect transistors (SiNW-FETs) can be used to sense very low concentration (fM) of pathogenic factors in controlled phosphate buffered saline. In this paper, we show SiNW-FETs as biosensors for the detection of cancer markers in tumor extracts, as proof of our technology to successfully work on real patients' sample. In particular, we achieved the detection of exogenously added rabbit antigen in a much more complex environment, i.e., a human breast tumor extract. Our results show specific and high sensitive antigen detection with p-type SiNW-FETs in the femtomolar range. Further and most importantly, the wires sense rabbit antigen molecules in the presence of a 100 000 mass excess of nonspecific protein, indicating that the sensor is extremely resistant to noise.
Non-conversion on auramine smear microscopy indicates a lack of treatment response, possibly associated with initial rifampicin-resistant tuberculosis (RR-TB). However, dead bacteria still stain ...positive and may be detected. Fluorescein diacetate smear microscopy (FDA) shows live mycobacteria only. Therefore, we studied the potential of 2-month (2M) FDA for the identification of initial RR-TB.
Between 2015 and 2018, we enrolled new smear-positive pulmonary TB patients from five local centres in Bamako, Mali. After baseline screening, sputum samples were collected at 1M, 2M, 5M and 18M. We used
B sequencing to identify initial RR-TB.
Of 1359 patients enrolled, 1019 (75%) had
B sequencing results. Twenty-six (2.6%, 95%CI: 1.7-3.7) had mutations conferring rifampicin resistance. Most frequent
B mutations were located at the codons Asp435Val (42.4%) and Ser450Leu (34.7%). Among patients with initial RR-TB, 72.2% were FDA-negative at 2M (
0.2). The positive and negative predictive value of 5M FDA for culture-based failure was respectively 20.0% and 94.7%.
FDA did not identify the majority of patients with initial RR-TB or culture-based failure. As the full spectrum of mutations identified on sequencing was identified using Xpert, our data support its rapid universal implementation in Mali.
To identify strains of Mycobacterium tuberculosis complex (MTC) circulating in Bamako and to examine the relationship between the strains and their drug susceptibility profiles.
Between 2006 and ...2010, we conducted a cross-sectional study using spoligotyping to identify strains of MTC recovered from 126 tuberculosis (TB) patients under treatment in Bamako, Mali.
Three members of the MTC were isolated: M. tuberculosis (71.4%), M. africanum (27.8%) and M. bovis (0.8%). Of these, three strains were found to be the most prevalent: M. tuberculosis T1 (MTB T1; 38.9%), M. africanum F2 (MAF2; 26.2%) and M. tuberculosis Latin American and Mediterranean 10 (MTB LAM 10; 10.3%). MAF2 and MTB LAM 10 strains have a lower risk of multidrug resistance (MDR) than MTB T1 (respectively OR 0.1, 95%CI 0.03-0.4 and OR 0.1, 95%CI 0.01-0.8). Age ≥ 32 years (OR 1.4, 95%CI 0.4-3.9), negative human immunodeficiency virus status (OR 0.4, 95%CI 0.1-2.5) and male sex (OR 4, 95%CI 0.9-16.5) were not associated with MDR. The prevalence of MDR among treatment and retreatment failure patients was respectively 25% and 81.8% compared to new patients (2.9%).
This study indicates a low level of primary drug resistance in Bamako, affirms the importance of using correct drug regimens, and suggests that the MTB T1 strain may be associated with the development of resistance.
A high signal-to-noise ratio (SNR) in silicon nanowire (SiNW) field effect transistors (FETs) is crucial for detecting low concentrations of biological material as the signal changes are often small ...and difficult to be differentiated from the baseline signal. This reported work studies the low-frequency noise (1/f) as in Hooge's constant, αH, and the device detection limit of the SiNW FETs to evaluate the influence of the etching process used to define the nanowires (NWs). Two etching methods are compared: plane-dependent etching using potassium borate in water and reactive ion etching in Cl-based chemistry. All investigated devices have similar dopant type, doping concentration and dimensions, and were fabricated with the same process flow with the exception of the NW definition. The extracted average Hooge's constant for wet etching is found to be at least an order of magnitude lower (αH, avg = 7.96 × 10−4) compared with dry plasma-etched devices (αH, avg = 4.1 × 10−2), indicating a lower surface roughness and/or a lower amount of surface defects. This study shows that the newly developed method improves the electrical properties of the device, making it an interesting alternative to standard approaches used for fabrication of SiNW FETs as (bio)sensors.
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