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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 ; 295(2): 191-198, 2024 Aug.
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.
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
4.
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
5.
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.

6.
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
7.
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.

8.
Clin Infect Dis ; 67(11): 1736-1742, 2018 11 13.
Article in English | MEDLINE | ID: mdl-29897440

ABSTRACT

Background: Frequent use of antibiotics is thought to create selection pressure by clearing susceptible bacteria and allowing resistant bacteria to spread in a community. A cluster-randomized trial comparing 2 different frequencies of mass azithromycin distributions for trachoma provided a convenient experiment for determining the causal relationship between antibiotic consumption and antibiotic resistance. Methods: Twenty-four communities were randomized to either annual or biannual mass azithromycin distributions for trachoma. Randomization was stratified on health catchment area and trachoma prevalence. Swabs were processed for the genetic macrolide resistance determinants ermB and mefA/E in a masked fashion from a random sample of 120 preschool children before treatment and another 120 children after 2 years of mass antibiotics. Results: Macrolide resistance determinants were similar in the 12 annually and 12 biannually treated communities before treatment, with a median prevalence among preschool children of 20% (interquartile range [IQR], 10%-40%) in each group. By 24 months, macrolide resistance determinants were found more commonly in the biannually treated communities (median, 60% [IQR, 50%-80%]) than the annually treated communities (median, 40% [IQR, 20%-40%]; P < .001). Adjusting for baseline, the 24-month prevalence of macrolide resistance determinants in the biannual group was 29.4% higher than that of the annual group (95% confidence interval, 10.5%-56.7%). Conclusions: This randomized trial used direct genetic methods to confirm the causal relationship of community antibiotic consumption and antibiotic resistance. Communities randomized to less frequent use of antibiotics had a significantly lower prevalence of genetic antibiotic resistance determinants. Clinical Trials Registration: NCT00792922.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Drug Resistance, Multiple, Bacterial/genetics , Macrolides/administration & dosage , Nasopharynx/microbiology , Selection, Genetic , Trachoma/drug therapy , Administration, Oral , Anti-Bacterial Agents/therapeutic use , Azithromycin/administration & dosage , Azithromycin/therapeutic use , Bacterial Proteins/genetics , Child, Preschool , Cluster Analysis , Female , Humans , Infant , Infant, Newborn , Macrolides/therapeutic use , Male , Mass Drug Administration , Prevalence , Streptococcus pneumoniae/drug effects , Streptococcus pneumoniae/genetics
9.
Am J Epidemiol ; 187(9): 1840-1845, 2018 09 01.
Article in English | MEDLINE | ID: mdl-29617922

ABSTRACT

Prior studies have theorized that low chlamydial genetic diversity following mass azithromycin treatments for trachoma may create a population bottleneck that prevents the return of infection, but little empirical evidence exists to support this hypothesis. In this study, a single mass azithromycin distribution was administered to 21 communities in the Gurage Zone of Ethiopia in 2003. All children aged 1-5 years had conjunctival swabs performed before treatment and 2 and 6 months after treatment. All swabs positive for Chlamydia trachomatis at 2 months underwent typing of the gene encoding the major outer membrane protein (ompA) of C. trachomatis, as did the same number of swabs per community from the pretreatment and 6-month visits. Diversity of ompA types, expressed as the reciprocal of Simpson's index, was calculated for each community. In total, 15 ompA types belonging to the A and B genovars were identified. The mean diversity was 2.11 (95% confidence interval: 1.79, 2.43) before treatment and 2.16 (95% confidence interval: 1.76, 2.55) 2 months after treatment (P = 0.78, paired t test). Diversity of ompA was not associated with the prevalence of ocular chlamydia (P = 0.76) and did not predict subsequent changes in the prevalence of ocular chlamydia (P = 0.32). This study found no evidence to support the theory that ompA diversity is associated with transmission of ocular chlamydia.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Azithromycin/therapeutic use , Bacterial Outer Membrane Proteins/genetics , Chlamydia trachomatis/genetics , Trachoma/microbiology , Genetic Variation , Humans , Trachoma/drug therapy
10.
Clin Infect Dis ; 64(6): 743-750, 2017 03 15.
Article in English | MEDLINE | ID: mdl-27956455

ABSTRACT

Background: The World Health Organization recommends annual treatment of entire trachoma-endemic communities, although children typically have a higher load, longer duration, and greater likelihood of infection. Methods: Forty-eight communities in Matameye, Niger, were randomized to annual oral azithromycin treatment of the entire community or biannual treatment of children aged 0-12 years only. Both children and adults were monitored for ocular chlamydial infection by polymerase chain reaction. Results: The prevalence of childhood infection was reduced in the annually treated arm from 21.2% (95% confidence interval [CI], 15.2%-28.0%) at baseline to 5.8% (95% CI, 3.2%-9.0%) at 36 months (P < .001) and in the biannual arm from 20.2% (95% CI, 15.5%-25.3%) to 3.8% (95% CI, 2.2%-6.0%; P < .001). Adult infection in the annual arm was reduced from 1.7% (95% CI, .9%-2.7%) to 0.3% (95% CI, .0%-.7%) and in the biannual arm from 1.2% (95% CI, .5%-2.2%) to 0.0% (95% CI, .0%-.7%; P = .005). The effect of biannual treatment of children compared with annual treatment of the entire community in both children (95% CI, -.04% to .02%) and adults (95% CI, .9%-2.7%) excluded the prespecified noninferiority threshold of 6% (P = .003 and P < .001, respectively). Conclusions: Periodic distribution of antibiotics to children in trachoma-endemic communities reduces chlamydial infection in both children and untreated adults, suggesting a form of herd protection. Biannual treatment of children was comparable to (specifically, noninferior to) annual treatment of the entire community, and may offer lower antibiotic use and other logistical advantages. Clinical Trials Registration: NCT00792922.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Trachoma/drug therapy , Adult , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/adverse effects , Azithromycin/administration & dosage , Azithromycin/adverse effects , Azithromycin/therapeutic use , Child, Preschool , Chlamydia trachomatis/drug effects , Female , Humans , Male , Prevalence , Time Factors , Trachoma/epidemiology , Trachoma/microbiology , Treatment Outcome
11.
Clin Infect Dis ; 64(9): 1147-1153, 2017 05 01.
Article in English | MEDLINE | ID: mdl-28402408

ABSTRACT

Background: Antibiotic exposure can alter the gut microbiome. We evaluate the effects of azithromycin on the gut microbiome diversity of children from an antibiotic-naive community in Niger. Methods: A population-based sample of 80 children aged 1-60 months in the Dosso region of Niger was randomized to receive a single dose of either oral azithromycin or placebo. Fecal samples were collected immediately before treatment and 5 days after treatment for 16S rRNA gene sequencing. The prespecified outcome was α-diversity (inverse Simpson's α-diversity index), with secondary outcomes of ß and γ Simpson's and Shannon's diversities. Results: At 5 days after treatment, 40 children aged 1-60 months were analyzed in the azithromycin-treated group and 40 children in the placebo-treated group. Diversity of the gut microbiome was significantly lower in the treated group (inverse Simpson's α-diversity, 5.03; 95% confidence interval [CI], 4.08-6.14) than in the placebo group (6.91; 95% CI, 5.82-8.21; P = .03). Similarly, the Shannon's α-diversity was lower in the treated group (10.60; 95% CI, 8.82-12.36) than the placebo group (15.42; 95% CI, 13.24-17.80; P = .004). Simpson's community-level (γ) diversity decreased with azithromycin exposure from 17.72 (95% CI, 13.80-20.21) to 10.10 (95% CI, 7.80-11.40; P = .00008), although ß-diversity was not significantly reduced (2.56, 95% CI, 1.88-3.12; to 2.01, 95% CI, 1.46-2.51; P = .26). Conclusions: Oral administration of azithromycin definitively decreases the diversity of the gut microbiome of children in an antibiotic-naive community. Clinical Trials Registration: NCT02048007.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Azithromycin/administration & dosage , Bacteria/drug effects , Gastrointestinal Microbiome/drug effects , Gastrointestinal Tract/microbiology , Administration, Oral , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Biodiversity , Child, Preschool , Cluster Analysis , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Female , Humans , Infant , Male , Niger , Phylogeny , Placebos/administration & dosage , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
12.
Langmuir ; 33(22): 5464-5472, 2017 06 06.
Article in English | MEDLINE | ID: mdl-28514172

ABSTRACT

A facile and rapid method for synthesizing single crystal gold spherical or platelet (nonspherical) particles is reported. The reaction takes place at the interface of two immiscible liquids where the reducing agent decamethylferrocene (DmFc) was initially added to hexane and gold chloride (AuCl4-) to an aqueous phase. The reaction is spontaneous at room temperature, leading to the creation of Au nanoparticles (AuNP). A flow focusing microfluidic chip was used to create emulsion droplets, allowing the same reaction to take place within a series of microreactors. The technique allows the number of droplets, their diameter, and even the concentration of reactants in both phases to be controlled. The size and shape of the AuNP are dependent upon the concentration of the reactants and the size of the droplets. By tuning the reaction parameters, the synthesized nanoparticles vary from nanometer to micrometer sized spheres or platelets. The surfactant used to stabilize the emulsion was also shown to influence the particle shape. Finally, the addition of other nanoparticles within the droplet allows for core@shell particles to be readily formed, and we believe this could be a versatile platform for the large scale production of core@shell particles.

14.
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.

15.
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.

16.
Med Sci Sports Exerc ; 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38875487

ABSTRACT

INTRODUCTION: Increases in skeletal muscle size occur in response to prolonged exposure to resistance training that is typically ascribed to increased muscle fibre size. Whether muscle fibre number also changes remains controversial, and a paucity of data exists about myofibrillar structure. This cross-sectional study compared muscle fibre and myofibril characteristics in long-term resistance-trained (LRT) versus untrained (UNT) individuals. METHODS: The maximal anatomical cross-sectional area (ACSAmax) of the biceps brachii muscle was measured by MRI in 16 LRT (5.9 ± 3.5 years' experience) and 13 UNT males. A muscle biopsy was taken from the biceps brachii to measure muscle fibre area, myofibril area and myosin spacing. Muscle fibre number, myofibril number in total and per fibre were estimated by dividing ACSAmax by muscle fibre area or myofibril area, and muscle fibre area by myofibril area, respectively. RESULTS: Compared to UNT, LRT individuals had greater ACSAmax (+70%, P < 0.001), fibre area (+29%, P = 0.028), fibre number (+34%, P = 0.013), and myofibril number per fibre (+49%, P = 0.034) and in total (+105%, P < 0.001). LRT individuals also had smaller myosin spacing (-7%, P = 0.004; i.e. greater packing density) and a tendency towards smaller myofibril area (-16%, P = 0.074). ACSAmax was positively correlated with fibre area ( r = 0.526), fibre number ( r = 0.445) and myofibril number (in total r = 0.873 and per fibre r = 0.566), and negatively correlated with myofibril area ( r = -0.456) and myosin spacing ( r = -0.382) (all P < 0.05). CONCLUSIONS: The larger muscles of LRT individuals exhibited more fibres in cross-section and larger muscle fibres, which contained substantially more total myofibrils and more packed myofilaments than UNT participants, suggesting plasticity of muscle ultrastructure.

17.
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
18.
Lancet ; 379(9811): 143-51, 2012 Jan 14.
Article in English | MEDLINE | ID: mdl-22192488

ABSTRACT

BACKGROUND: In trachoma control programmes, azithromycin is distributed to treat the strains of chlamydia that cause ocular disease. We aimed to compare the effect of annual versus twice-yearly distribution of azithromycin on infection with these strains. METHODS: We did a cluster-randomised trial in 24 subdistricts in northern Ethiopia, which we randomly assigned to receive annual or twice-yearly treatment for all residents of all ages. Random assignment was done with the RANDOM and SORT functions of Microsoft Excel. All individuals were offered their assigned treatment of a single, directly observed, oral dose of azithromycin. A 6 week course of topical 1% tetracycline ointment, applied twice daily to both eyes but not directly observed, was offered as an alternative to azithromycin in patients younger than 12 months, and in patients with self-reported pregnancy, with allergy, or who refused azithromycin. Our primary, prespecified outcome was the prevalence of ocular chlamydial infection in a random sample of children aged 0-9 years at baseline and every 6 months for a total of 42 months within sentinel villages. Our analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00322972. FINDINGS: Antibiotic coverage of children aged 1-9 years was greater than 80% (range 80·9 to 93·0) at all study visits. In the groups treated annually, the prevalence of infection in children aged 0-9 years was reduced from a mean 41·9% (95% CI 31·5 to 52·2) at baseline to 1·9% (0·3 to 3·5) at 42 months. In the groups treated twice yearly, the prevalence of infection was reduced from a mean 38·3% (29·0 to 47·6) at baseline to 3·2 % (0·0 to 6·5) at 42 months. The prevalence of ocular chlamydial infection in children aged 0-9 years in groups treated annually was not different from that of the groups treated twice yearly at 18, 30, and 42 months (pooled regression p>0·99, 95 % CI -0·06 to 0·06). The mean elimination time in the twice-yearly treatment group was 7·5 months earlier (2·3 to 17·3) than that of the annual group (p=0·10, Cox proportional hazards model). INTERPRETATION: After 42 months of treatment, the prevalence of ocular infection with chlamydia was similar in the groups treated annually and twice yearly. However, elimination of infection might have been more rapid in the groups of villages that received treatment twice yearly. FUNDING: National Institutes of Health (NEI U10 EY016214).


Subject(s)
Anti-Bacterial Agents/administration & dosage , Azithromycin/administration & dosage , Trachoma/drug therapy , Child , Child, Preschool , Directly Observed Therapy , Endemic Diseases , Ethiopia/epidemiology , Female , Humans , Hypersensitivity/complications , Infant , Infant, Newborn , Intention to Treat Analysis , Ointments , Pregnancy , Pregnancy Complications/drug therapy , Tetracycline/administration & dosage
19.
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
20.
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
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