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1.
PLoS Med ; 21(5): e1004386, 2024 May.
Article in English | MEDLINE | ID: mdl-38709718

ABSTRACT

BACKGROUND: Randomized controlled trials found that twice-yearly mass azithromycin administration (MDA) reduces childhood mortality, presumably by reducing infection burden. World Health Organization (WHO) issued conditional guidelines for mass azithromycin administration in high-mortality settings in sub-Saharan Africa given concerns for antibiotic resistance. While prolonged twice-yearly MDA has been shown to increase antibiotic resistance in small randomized controlled trials, the objective of this study was to determine if macrolide and non-macrolide resistance in the gut increases with the duration of azithromycin MDA in a larger setting. METHODS AND FINDINGS: The Macrolide Oraux pour Réduire les Décès avec un Oeil sur la Résistance (MORDOR) study was conducted in Niger from December 2014 to June 2020. It was a cluster-randomized trial of azithromycin (A) versus placebo (P) aimed at evaluating childhood mortality. This is a sub-study in the MORDOR trial to track changes in antibiotic resistance after prolonged azithromycin MDA. A total of 594 communities were eligible. Children 1 to 59 months in 163 randomly chosen communities were eligible to receive treatment and included in resistance monitoring. Participants, staff, and investigators were masked to treatment allocation. At the conclusion of MORDOR Phase I, by design, all communities received an additional year of twice-yearly azithromycin treatments (Phase II). Thus, at the conclusion of Phase II, the treatment history (1 letter per 6-month period) for the participating communities was either (PP-PP-AA) or (AA-AA-AA). In Phase III, participating communities were then re-randomized to receive either another 3 rounds of azithromycin or placebo, thus resulting in 4 treatment histories: Group 1 (AA-AA-AA-AA-A, N = 51), Group 2 (PP-PP-AA-AA-A, N = 40), Group 3 (AA-AA-AA-PP-P, N = 27), and Group 4 (PP-PP-AA-PP-P, N = 32). Rectal swabs from each child (N = 5,340) were obtained 6 months after the last treatment. Each child contributed 1 rectal swab and these were pooled at the community level, processed for DNA-seq, and analyzed for genetic resistance determinants. The primary prespecified outcome was macrolide resistance determinants in the gut. Secondary outcomes were resistance to beta-lactams and other antibiotic classes. Communities recently randomized to azithromycin (groups 1 and 2) had significantly more macrolide resistance determinants than those recently randomized to placebo (groups 3 and 4) (fold change 2.18, 95% CI 1.5 to 3.51, Punadj < 0.001). However, there was no significant increase in macrolide resistance in communities treated 4.5 years (group 1) compared to just the most recent 2.5 years (group 2) (fold change 0.80, 95% CI 0.50 to 1.00, Padj = 0.010), or between communities that had been treated for 3 years in the past (group 3) versus just 1 year in the past (group 4) (fold change 1.00, 95% CI 0.78 to 2.35, Padj = 0.52). We also found no significant differences for beta-lactams or other antibiotic classes. The main limitations of our study were the absence of phenotypic characterization of resistance, no complete placebo arm, and no monitoring outside of Niger limiting generalizability. CONCLUSIONS: In this study, we observed that mass azithromycin distribution for childhood mortality among preschool children in Niger increased macrolide resistance determinants in the gut but that resistance may plateau after 2 to 3 years of treatment. Co-selection to other classes needs to be monitored. TRIAL REGISTRATION: NCT02047981 https://classic.clinicaltrials.gov/ct2/show/NCT02047981.


Subject(s)
Anti-Bacterial Agents , Azithromycin , Drug Resistance, Bacterial , Macrolides , Mass Drug Administration , Humans , Azithromycin/therapeutic use , Niger , Child, Preschool , Anti-Bacterial Agents/therapeutic use , Infant , Female , Male , Macrolides/therapeutic use , Child Mortality
2.
J Microsc ; 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38482774

ABSTRACT

A new method is proposed to measure the linear coefficient of thermal expansion (CTE) of solid metals and ceramics of micron-sized dimensions. This approach uses a focused ion beam (FIB) to extract and transfer a slab of the sample, typically (15-20) ×10 × (3-5) µm onto a Micro-Electro-Mechanical Systems (MEMS) in situ heating holder inside a scanning electron microscope (SEM). CTE is thereafter calculated by image correlating the change of length (ΔL) between the fiducial marks on the slab as a function of temperature, taking advantage of the temperature calibration of the MEMS heating holder and nanometre resolution of the scanning electron microscope. The CTE results are validated to be consistent with standard copper and silicon. We further demonstrate the method on a graphene platelet reinforced copper composite and a graphite filler phase isolated from a bulk sample, these represent materials that cannot be practically synthesised or isolated at the macro-scale. Errors associated with the measurement are discussed.

3.
Schizophrenia (Heidelb) ; 10(1): 23, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38388554

ABSTRACT

Accumulating evidence has supported the implementation of dance/movement therapy (DMT) as a promising intervention for patients with schizophrenia (SCZ). However, its effect on body weight and metabolic profile in SCZ remains unclear. This study aimed to evaluate the outcome of a 12-week DMT session on weight and lipid profile in patients with SCZ using a randomized, single-blinded, controlled trial design. This study encompassed two groups of long-term hospitalized patients with SCZ, who were randomly assigned to the DMT intervention (n = 30) or the treatment as usual (TAU) group (n = 30). Metabolic markers, including weight, body mass index (BMI), fasting glucose, triglycerides, and total cholesterol were measured in both groups at two measurement points (at baseline and the end of the 12-week treatment). We found that DMT intervention significantly decreased body weight (F = 5.5, p = 0.02) and BMI (F = 5.7, p = 0.02) as compared to the TAU group. However, no significance was observed in other metabolic markers, including fasting glucose, triglycerides, and total cholesterol after treatment (all p > 0.05). Our study indicates that a 12-week, 24-session DMT program may be effective in decreasing body weight and BMI in long-term hospitalized patients with SCZ. DMT intervention may be a promising treatment strategy for long-term inpatients in the psychiatric department.

5.
Am J Trop Med Hyg ; 110(2): 291-294, 2024 02 07.
Article in English | MEDLINE | ID: mdl-38227963

ABSTRACT

Mass antibiotic distribution to preschool children resulted in alterations of the gut microbiome months after distribution. This individually randomized, placebo-controlled trial evaluated changes in the gut microbiome and resistome in children aged 8 days to 59 months after one dose of oral azithromycin in Burkina Faso. A total of 450 children were randomized in a 1:1 ratio to either placebo or azithromycin. Rectal samples were collected at baseline, 2 weeks, and 6 months after randomization and subjected to DNA deep sequencing. Gut microbiome diversity and normalized antimicrobial resistance determinants for different antibiotic classes were evaluated. Azithromycin decreased gut bacterial diversity (Shannon P < 0.0001; inverse Simpson P < 0.001) 2 weeks after treatment relative to placebo. Concurrently, the normalized abundance of macrolide resistance genetic determinants was 243-fold higher (95% CI: 76-fold to 776-fold, P < 0.0001). These alterations did not persist at 6 months, suggesting that disruptions were transient. Furthermore, we were unable to detect resistance changes in other antibiotic classes, indicating that co-resistance with a single course of azithromycin when treated at the individual level was unlikely.


Subject(s)
Azithromycin , Gastrointestinal Microbiome , Humans , Child, Preschool , Azithromycin/therapeutic use , Anti-Bacterial Agents/therapeutic use , Macrolides , Drug Resistance, Bacterial/genetics
6.
ACS Appl Mater Interfaces ; 16(1): 1846-1860, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38113398

ABSTRACT

Printing of electrical circuits and interconnects using isotropic conductive adhesives (ICAs) is of great interest due to their low-temperature processing and compatibility with substrates for applications in sensors, healthcare, and flexible devices. As a lower cost alternative to silver (Ag), copper (Cu)-filled ICAs are desirable but limited by the formation of high-resistivity Cu surface oxides. To overcome this limitation, self-assembled monolayers (SAMs) of octadecanethiol (ODT) have been demonstrated to reduce the oxidation of micrometer-scale Cu powder particles for use in ICAs. However, the deposition and function of the SAM require further investigation, as described in this paper. As part of this work, the stages of the SAM deposition process, which included etching with hydrochloric acid to remove pre-existing oxides, were studied using X-ray photoelectron spectroscopy (XPS), which showed low levels of subsequent Cu oxidation when ODT coated. The treated Cu powders were combined with one- or two-part epoxy resins to make Cu-ICAs, and the effect of the Cu surface condition and weight loading on electrical conductivity was examined. When thermally cured in an inert argon atmosphere, ICAs filled with Cu protected by ODT achieved electrical conductivity up to 20 × 105 S·m-1, comparable to Ag-ICAs, and were used to make a functional circuit. To understand the function of the SAM in these Cu-ICAs, scanning and transmission electron microscopy were used to examine the internal micro- and nano-structures along with the elemental distribution at the interfaces within sections taken from cured samples. Sulfur (S), indicative of the ODT, was still detected at the internal polymer-metal interface after curing, and particle-to-particle contacts were also examined. XPS also identified S on the surface of cured Cu-ICAs even after thermal treatment. Based on the observations, electrical contact and conduction mechanisms for these Cu-filled ICAs are proposed and discussed.

7.
Urolithiasis ; 51(1): 104, 2023 Aug 16.
Article in English | MEDLINE | ID: mdl-37584873

ABSTRACT

Kidney donors with asymptomatic small kidney stones were increasingly accepted in kidney transplantation (KT) due to organ shortage and advances in endoscopic urology. However, recipients' clinical outcomes using these donors remained unclear. We conducted a meta-analysis to summarize transplant outcomes using these donors with asymptomatic small kidney stones. Finally, 15 retrospective studies were included. The prevalence of asymptomatic small kidney stones was 5.3% (95%CI 3.5-7.8%). After transplantation, low incidence of urinary fistula (0%, 95%CI 0-1.0%), obstruction (0%, 95%CI 0-1.1%), relapse of kidney graft stone (0.3%, 95%CI 0-2.5%), and delayed graft function (0.6%, 95%CI 0-3.5%) was reported. Pooled serum creatinine was 1.3 (95%CI 1.2-1.5) mg/dl and 1.4 (95%CI 1.2-1.6) mg/dl at post-transplant 1 month and 1 year, respectively. Notably, we observed numerically higher relapse rate after conservative management (1.8% [0-9.2%] vs 0% [0-1.8%]) but numerically higher DGF rate after surgical removal of asymptomatic stones (1.8% [0-7.0%] vs 0% [0-1.9%]). Overall, short-term transplant outcomes using kidneys with asymptomatic small stones were acceptable. However, long-term transplant outcomes remained unexplored. Well-designed prospective studies are also needed to compare the efficacy of conservative management with surgical removal of "donors' gifted" asymptomatic kidney stones.


Subject(s)
Kidney Calculi , Kidney , Humans , Retrospective Studies , Prospective Studies , Tissue Donors , Kidney Calculi/epidemiology , Kidney Calculi/etiology , Kidney Calculi/surgery
8.
Schizophrenia (Heidelb) ; 9(1): 47, 2023 Jul 31.
Article in English | MEDLINE | ID: mdl-37524713

ABSTRACT

Fractures are common accidents for long-term hospitalized patients with schizophrenia (SZ) in psychiatric hospitals, and once they occur, patients usually endure the pain of fractures for a long time. Accumulating evidence has supported the implementation of dance/movement therapy (DMT) as a promising intervention for patients with SZ. However, no research has been conducted to investigate its role in balance ability in SZ. This study was designed to investigate the efficacy of a 12-week DMT intervention in bone mineral density and balance ability in patients with SZ using a randomized, controlled trial design. A total of 58 veterans with SZ were randomly assigned to the DMT intervention group (n = 29) and the treatment-as-usual (TAU) group (n = 29). Bone mineral density (BMD) and balance ability were measured in both groups at two measurement points (at baseline and at the end of Week 12). We found that patients in the DMT intervention group had significant improvements in BMD and balance ability compared with the TAU group by using repeated measures analysis of variance. Treatment with DMT demonstrated a significant improvement in BMD from baseline to week 12 (0.03, 95% CI: 0.01-0.05). For the Berg total score and static and dynamic balance, the mean changes in the DMT group were 7.3 (95% CI: 5.6-9.0), 4.0 (95% CI: 0.9-7.1), and 3.7 (95% CI: 2.6-4.8), respectively. Regression analysis showed that baseline BMD was a significant predictor of improvement in BMD from baseline to week 12 in the DMT group (ß = 0.58, p < 0.001). Our results suggest for the first time that DMT intervention may be effective in beneficially regulating BMD and balance ability in SZ patients.

9.
Nephrology (Carlton) ; 28(11): 611-619, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37469214

ABSTRACT

BACKGROUND: Conflicting results have been reported regarding the association between psoriasis and risk of chronic kidney diseases (CKD). Furthermore, the causal nature of the possible association remains unexplored. METHODS: We conducted a population-based cross-sectional study using data from National Health and Nutrition Examination Survey (NHANES). Logistic regression analyses were conducted to estimate potential association between psoriasis and CKD risk. Further, we evaluated causality by performing a Mendelian randomization analysis using large-scale genome-wide association studies of psoriasis and CKD. Inverse variance-weighted (IVW) analysis was used as the primary method. RESULTS: In the observational study, 16 750 participants were included. Overall, 39 of 429 patients with psoriasis had CKD (9.1%) compared with 1481 of 16 321 without psoriasis (9.1%). In the fully adjusted model, psoriasis was not associated with CKD (OR: 0.77, 95%CI: 0.53-1.10). In the MR analysis, 36 single-nucleotide polymorphisms (SNPs) were selected as instrumental variables. The IVW analysis reported that genetically predicted psoriasis was associated with a higher risk of CKD (OR: 1.025, 95%CI: 1.001-1.049). After removing 2 SNPs associated with heterogeneity, the association remained (OR: 1.028, 95%CI: 1.006-1.050). CONCLUSION: Genetically predicted psoriasis was associated with a higher risk of CKD. This association may be important for clinicians to monitor kidney function and prescribe potentially nephrotoxic drugs during psoriasis management.

10.
Environ Sci Technol ; 57(1): 76-84, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36519925

ABSTRACT

Saltation is an important wind erosion process that can cause the modification and breakdown of particles by aeolian abrasion. It is recognized that microplastic particles can be transported by wind, but the effect of saltation on microplastic properties is unknown. This study examined the impact of simulated saltation alongside quartz grains on the size, shape, and surface properties of spherical microplastic beads. The diameter of the microplastics was reduced by 30-50% over 240-300 h of abrasion with a mass loss of c. 80%. For abrasion periods up to 200 h, the microplastic beads remained spherical with minimal change to overall shape. Over 95% of the fragments of plastic removed from the surface of the microbeads during the abrasion process had a diameter of ≤10 µm. In addition, during the abrasion process, fine particles derived from breakdown of the quartz grains became attached to the surfaces of the microbeads resulting in a reduction in carbon and an increase in silicon detected on the particle surface. The results suggest that microplastics may be mechanically broken down during aeolian saltation and small fragments produced have the potential for long distance transport as well as being within the size range for human respiration.


Subject(s)
Microplastics , Plastics , Humans , Quartz
11.
J Nephrol ; 36(3): 755-765, 2023 04.
Article in English | MEDLINE | ID: mdl-36378477

ABSTRACT

BACKGROUND: Magnesium deficiency is common in patients with chronic kidney diseases (CKD) due to restricted magnesium intake and impaired magnesium reabsorption. Based on pathophysiological risk factors influencing kidney magnesium reabsorption, a magnesium depletion score (MDS) was developed. Using MDS as a novel indicator for assessing body magnesium status, we hypothesized that it was associated with clinical prognosis. METHODS: We conducted a prospective population-based cohort study using data from the National Health and Nutrition Examination Survey 1999-2014 to explore the impact of MDS on the clinical outcomes of CKD patients. Propensity score-matched analyses were conducted to increase comparability. The primary outcome was all-cause mortality, and the secondary outcomes were cardiovascular-cause and cancer-cause mortality. RESULTS: After propensity score matching, 3294 CKD patients were divided into 2 groups: MDS ≤ 2 (N = 1647), and MDS > 2 (N = 1647). During a median follow-up of 75 months, Kaplan-Meier analyses showed that MDS > 2 was associated with worse 5- and 10-year overall survival (78.5% vs 73.4%; 53.1% vs 43.1%, P < 0.001). After adjusting for confounding variables, MDS was found to be an independent risk factor for all-cause mortality (HR:1.34, 95% CI 1.20-1.50, P < 0.001). MDS > 2 was also associated with higher cardiovascular-cause mortality (16.2% VS 11.6%, P = 0.005). Multivariate competing risk analysis revealed that MDS > 2 was an independent risk factor (HR: 1.33, 95% CI 1.06-1.66, P = 0.012). Subgroup analyses reported that MDS > 2 increased all-cause mortality and cardiovascular-cause mortality only in patients with inadequate magnesium intake (P < 0.001, P < 0.001) but not in those with adequate intake (P = 0.068, P = 0.920). CONCLUSIONS: A magnesium depletion score > 2 was independently associated with higher long-term cardiovascular-cause and all-cause mortality in CKD patients.


Subject(s)
Magnesium Deficiency , Magnesium , Renal Insufficiency , Mortality , Renal Insufficiency/mortality , Prospective Studies , Nutrition Surveys , Cohort Studies
12.
Clin Infect Dis ; 76(6): 1038-1042, 2023 03 21.
Article in English | MEDLINE | ID: mdl-36477547

ABSTRACT

BACKGROUND: Mass administration of azithromycin is an established strategy for decreasing the prevalence of trachoma in endemic areas. However, nearby untreated communities could serve as a reservoir that may increase the chances of chlamydia reinfection in treated communities. METHODS: As part of a cluster-randomized trial in Ethiopia, 60 communities were randomized to receive mass azithromycin distributions and 12 communities were randomized to no treatments until after the first year. Ocular chlamydia was assessed from a random sample of children per community at baseline and month 12. Distances between treated and untreated communities were assessed from global positioning system coordinates collected for the study. RESULTS: The pretreatment prevalence of ocular chlamydia among 0 to 9 year olds was 43% (95% confidence interval [CI], 39%-47%), which decreased to 11% (95% CI, 9%-14%) at the 12-month visit. The posttreatment prevalence of chlamydia was significantly higher in communities that were closer to an untreated community after adjusting for baseline prevalence and the number of mass treatments during the year (odds ratio, 1.12 [95% CI, 1.03-1.22] for each 1 km closer to an untreated community). CONCLUSIONS: Mass azithromycin distributions to wide, contiguous geographic areas may reduce the likelihood of continued ocular chlamydia infection in the setting of mass antibiotic treatments.


Subject(s)
Anti-Bacterial Agents , Trachoma , Child , Humans , Infant , Anti-Bacterial Agents/therapeutic use , Trachoma/drug therapy , Trachoma/epidemiology , Trachoma/prevention & control , Azithromycin/therapeutic use , Chlamydia trachomatis , Mass Drug Administration , Prevalence
13.
PLoS Negl Trop Dis ; 16(3): e0010237, 2022 03.
Article in English | MEDLINE | ID: mdl-35344559

ABSTRACT

BACKGROUND: The chlamydial major outer membrane protein, encoded by the ompA gene, is a primary target for chlamydial vaccine research. However, human studies of ompA-specific immunity are limited, and prior studies have been limited in differentiating re-infection from persistent infection. The purpose of this study was to assess whether children living in trachoma-endemic communities with re-infections of ocular chlamydia were more likely to be infected with a different or similar genovar. METHODOLOGY AND FINDINGS: The study included 21 communities from a trachoma-hyperendemic area of Ethiopia that had been treated with a mass azithromycin distribution for trachoma. Conjunctival swabbing was offered to all children younger than 5 years of age at baseline (i.e., pre-treatment), and then at follow-up visits 2 and 6 months later. Swabs were subjected to polymerase chain reaction (PCR) to detect C. trachomatis. A random sample of 359 PCR-positive swabs, stratified by study visit and study community, was chosen for ompA sequencing. In addition, ompA sequencing was performed on all swabs of 24 children who experienced chlamydial re-infection (i.e., positive chlamydial test before treatment, negative test 2 months following mass distribution of azithromycin, and again a positive test 6 months post-treatment). ompA sequencing was successful for 351 of 359 swabs of the random sample and 44 of 48 swabs of the re-infection sample. In the random sample, ompA types clustered within households more than would be expected by chance. Among the 21 re-infected children with complete ompA data, 14 had the same ompA type before and after treatment. CONCLUSION: The high frequency of ompA concordance suggests incomplete genovar-specific protective immunity and the need for multiple antigens as vaccine targets.


Subject(s)
Azithromycin , Trachoma , Azithromycin/therapeutic use , Child , Chlamydia trachomatis/genetics , Conjunctiva , Humans , Polymerase Chain Reaction , Trachoma/drug therapy , Trachoma/epidemiology , Trachoma/prevention & control
14.
Cornea ; 41(10): 1260-1264, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-34483276

ABSTRACT

PURPOSE: The aim of this study was to evaluate the effect of the 4 times per year mass azithromycin distributions on the ocular surface microbiome of children in a trachoma endemic area. METHODS: In this cluster-randomized controlled trial, children aged 1 to 10 years in rural communities in the Goncha Seso Enesie district of Ethiopia were randomized to either no treatment or treatment with a single dose of oral azithromycin (height-based dosing to approximate 20 mg/kg) every 3 months for 1 year. Post hoc analysis of ocular surface Chlamydia trachomatis load, microbial community diversity, and macrolide resistance determinants was performed to evaluate differences between treatment arms. RESULTS: One thousand two hundred fifty-five children from 24 communities were included in the study. The mean azithromycin coverage in the treated communities was 80% (95% CI: 73%-86%). The average age was 5 years (95% CI: 4-5). Ocular surface C. trachomatis load was reduced in children treated with the 4 times per year azithromycin ( P = 0.0003). Neisseria gonorrhoeae , Neisseria lactamica , and Neisseria meningitidis were more abundant in the no-treatment arm compared with the treated arm. The macrolide resistance gene ermB was not different between arms ( P = 0.63), but mefA / E was increased ( P = 0.04) in the azithromycin-treated arm. CONCLUSIONS: We found a reduction in the load of C. trachomatis and 3 Neisseria species in communities treated with azithromycin. These benefits came at the cost of selection for macrolide resistance.


Subject(s)
Microbiota , Trachoma , Anti-Bacterial Agents , Azithromycin , Child , Child, Preschool , Chlamydia trachomatis , Drug Resistance, Bacterial , Humans , Infant , Macrolides/pharmacology , Macrolides/therapeutic use , Prevalence , Trachoma/drug therapy , Trachoma/epidemiology
15.
Clin Infect Dis ; 73(7): 1292-1295, 2021 10 05.
Article in English | MEDLINE | ID: mdl-34037753

ABSTRACT

We evaluated the gut resistome of children from communities treated with 10 twice-yearly azithromycin distributions. Although the macrolide resistance remained higher in the azithromycin arm, the selection of non-macrolide resistance observed at earlier time points did not persist. Longitudinal resistance monitoring should be a critical component of mass distribution programs. CLINICAL TRIALS REGISTRATION: NCT02047981.


Subject(s)
Anti-Bacterial Agents , Azithromycin , Anti-Bacterial Agents/therapeutic use , Azithromycin/pharmacology , Child, Preschool , Drug Resistance, Bacterial/genetics , Humans , Macrolides/pharmacology , Mass Drug Administration
16.
Am J Trop Med Hyg ; 104(4): 1271-1277, 2021 02 01.
Article in English | MEDLINE | ID: mdl-33534742

ABSTRACT

The WHO recommends improving access to water as part of a comprehensive strategy for elimination of trachoma as a public health problem; however, this recommendation is not based on evidence from randomized trials. In a region of Ethiopia with hyperendemic trachoma, seven communities were randomized to a hand-dug well (HDW) and seven communities to no intervention to determine the impact of HDWs on the community prevalence of ocular chlamydia infection (primary prespecified outcome). All communities continued to receive government hygiene and sanitation services and outreach. Participants were not masked, given the nature of the intervention, but laboratory personnel were masked to treatment allocation. Hand-dug wells were successfully built in six of the seven communities; five of these wells were still functional at the conclusion of the trial. At the end of the trial, an average of 74% of households reported traveling < 30 minutes to collect water in the HDW arm, compared with 45% in the control arm, and the daily volume of water used for hygiene was similar (e.g., mean of 0.7 L per person in each arm). The pseudo-median prevalence of ocular chlamydia among 0- to 5-year old children at the 24-month visit was 23% in the HDW group and 13% in the control group (P > 0.99). This small cluster-randomized trial provided no evidence to suggest that simply constructing HDWs, in the absence of other hygiene promotion activities, is effective for reducing transmission of ocular chlamydia.


Subject(s)
Chlamydia trachomatis/pathogenicity , Gonorrhea/prevention & control , Hand , Sanitation/methods , Water Wells , Child , Child, Preschool , Endemic Diseases , Ethiopia/epidemiology , Gonorrhea/epidemiology , Humans , Hygiene , Infant , Infant, Newborn , Infant, Newborn, Diseases , Prevalence , Public Health , Trachoma
17.
Am J Trop Med Hyg ; 103(1): 234-237, 2020 07.
Article in English | MEDLINE | ID: mdl-32394877

ABSTRACT

Nucleic acid amplification tests are increasingly used to detect ocular chlamydia infection in trachoma research and programs. To evaluate the reliability of Chlamydia trachomatis detection by the Abbott RealTime CT/NG assay (Abbott Molecular, Inc., Des Plaines, IL) on the m2000 platform, three conjunctival samples were collected from each of 200 children aged 0-9 years in Ethiopia: two from the right eye and one from the left eye. Four aliquots were processed for each child: two from the first right eye sample, one from the second right eye sample, and one from the left eye sample. Sixty-nine swabs were processed in a U.S. laboratory and 131 in an Ethiopian laboratory. Intra-class correlation coefficients (ICCs) were high when comparing two aliquots from the same swab (ICC ranged from 0.96 to 0.99), two separate swabs from the right eye (0.89-0.91), and one right and one left eye swab (0.87-0.89), indicating reliable chlamydial load assessment across different samples and laboratory settings.


Subject(s)
Chlamydia trachomatis , Conjunctivitis, Inclusion/diagnosis , Nucleic Acid Amplification Techniques/methods , Child , Child, Preschool , Conjunctivitis, Inclusion/epidemiology , Conjunctivitis, Inclusion/microbiology , Cross-Sectional Studies , Ethiopia/epidemiology , Eye/microbiology , Female , Humans , Infant , Infant, Newborn , Male , Sensitivity and Specificity
19.
J Colloid Interface Sci ; 569: 204-210, 2020 Jun 01.
Article in English | MEDLINE | ID: mdl-32113017

ABSTRACT

The interface between two immiscible liquids represent an ideal substrate for the assembly of nanomaterials. The defect free surface provides a reproducible support for creating densely packed ordered materials. Here a droplet flow reactor is presented for the synthesis and/or assembly of nanomaterials at the interface of the emulsion. Each droplet acts as a microreactor for a reaction between decamethylferrocene (DmFc) within the hexane and metal salts (Ag+/Pd2+) in the aqueous phase. The hypothesis was that a spontaneous, interfacial reaction would lead to the assembly of nanomaterials creating a Pickering emulsion. The subsequent removal of the solvents showed how the Ag nanoparticles remain trapped at the interface and retain the shape of the droplet, however the Pd nanoparticles were dispersed with no tertiary structure. To further exploit this, a one-step process where the particles are synthesised and then assembled into core-shell materials was proposed. The same reactions were performed in the presence of oleic acid stabilised iron oxide nanoparticles dispersed within the hexane. It was shown that by changing the reaction rate and ratio between metal and iron oxide a continuous coating of metal nanoparticles can be formed on top of an iron oxide microsphere, or form a uniform composite. These insights offer a new method and chemistry within flow reactors for the creation of palladium and silver nanoparticles. We use the technique to create metal coated iron oxide nanomaterials but the methodology could be easily transferred to the assembly of other materials.

20.
J Microsc ; 279(3): 212-216, 2020 Sep.
Article in English | MEDLINE | ID: mdl-31985812

ABSTRACT

A site-specific xenon plasma focused ion beam preparation technique for microcantilever samples (1-20 µm width and 1:10 aspect ratio) is presented. The novelty of the methodology is the use of a chunk lift-out onto a clean silicon wafer to facilitate easy access of a low-cost probe type indenter which provides bending force measurement. The lift-out method allows sufficient room for the indenter and a line of sight for the electron beam to enable displacement measurement. An electroplated nanotwinned copper (NTC) was cut to a 3 × 3 × 25 µm microbeam and in situ mechanically tested using the developed technique. It demonstrated measured values of Youngs modulus of 78.7 ± 11 GPa and flow stress of 0.80 ± 0.05 GPa, which is within the ranges reported in the literature. LAY DESCRIPTION: In this paper a site specific method is present for making particularly small mechanical tests samples, of the order of 100th the size of a human hair. These small samples can then be used to determine the mechanical properties of the bulk material. Copper with a nano twinned grain structure is used as a test medium. Ion milling was used to cut the sample to shape and a micro probe was used for mechanical testing. Ion milling can cut away very small volumes of material as it accelerates ions at the surface of the sample, atomically machining the sample. Micro probes are a cost-effective small-scale load measurement devices, however, they require a large area for accessing the sample. The indenter requirements are a problem when making you samples with ion milling as ion millers are best at making small cuts. Our aim was to design a cutting strategy which reduces the amount of cutting required while allowing samples to be fabricated anywhere on the sample. We used a chunk lift out technique to remove a piece of material which is then welded to a wafer of silicon this gives sufficient space around the sample for ion milling and testing. The additional space allowed easy access for the probe. A 3 × 3 × 10 µm micro cantilever beam was cut out from copper, this beam was then bent. The force from bending and distance bent was measured and converted into Youngs modulus which is a measure of flexibility. The modulus value measured was comparable to the values reported in other papers.

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