ABSTRACT
Research on transactional sexual relationships has largely focused on women's perspectives. Better understanding the men's views-especially regarding relationships with adolescent girls and young women-can inform HIV prevention efforts. In 2017, 134 in-depth interviews were conducted with the male partners of girls and young women aged 19-47 years, 94 in Uganda and 40 in Eswatini. Respondents were recruited at venues such as bars where men and potential partners meet and through other young women. Most respondents believed that providing money/gifts was the way to establish relationships with women in their communities, a context that some found undesirable. Young women were mainly perceived as actively pursuing transactional sex for material goods, but respondents also described economically impoverished women who were manipulated into relationships. Men described conflict with longer term partners as a driver to seeking younger partners, who were more compliant. Transaction dominates the male partners of adolescent girls and young women's understanding of sexual relationships, and inequitable power dynamics are reinforced by seeking younger partners. However, some respondents' discontent with this dynamic suggests an opportunity for change. HIV prevention programmes should directly address the underlying drivers of transactional relationships (e.g. gender norms) and work with men who question the practice.
Subject(s)
HIV Infections , Sexual Partners , Adolescent , Eswatini , Female , HIV Infections/prevention & control , Humans , Male , Sexual Behavior , UgandaABSTRACT
The increasing number of coronavirus disease 2019 (COVID-19) cases in the community has posed a significant epidemic pressure on healthcare settings. When healthcare workers (HCWs) acquire COVID-19, contact tracing and epidemiological investigation might not be adequate for determining the source of transmission. Here, we report a phylogenetic investigation involving two infected HCWs and nine patients to determine whether patient-to-HCW transmission had occurred in a hospital without a previous COVID-19 outbreak. This is the first study to apply phylogenomics to investigate suspected nosocomial transmission in a region with low prevalence of COVID-19. Our results do not support the occurrence of direct patient-to-HCW transmission.
Subject(s)
COVID-19 , Disease Outbreaks , Health Personnel , Humans , Phylogeny , SARS-CoV-2ABSTRACT
Tuberculosis (TB) is one of the leading causes of morbidity and mortality in different zones of Ethiopia. This study was undertaken to identify the strains of Mycobacterium tuberculosis and evaluate their drug sensitivity profiles in the Arsi Zone. A total of 111 isolates of M. tuberculosis from individuals with pulmonary TB were included and speciation and strain identification were performed using Region of difference 9 and spoligotyping, respectively. The drug sensitivity patterns were assessed using Bactec MGIT 960 SIRE and GenoType MTBDRplus line probe assays. Of 111 isolates, 83% were interpretable and 56 different spoligotype patterns were identified. From these, 22 patterns were shared types while the remaining 34 were orphans. The predominant shared types were spoligotype international type (SIT) 149 and SIT53, comprising 12 and 11 isolates, respectively. Euro-American lineage was the dominant lineage followed by East-African-Indian. Phenotypically, 17.2% of tested isolates were resistant to any first-line drugs and 3.1% were multidrug-resistant. Higher (6.2%) mono-resistance was observed to streptomycin, and no resistance was observed to rifampicin or ethambutol. Genotypically, five (5.4%) isolates were resistant to isoniazid and mutated at codon S315T1 of katG. In contrast, only 1.1% of the isolates were resistant to rifampicin and were mutated at codon S531L of rpoB gene. In this study, a high proportion of orphan strains were isolated, which could suggest the presence of new strains and a high percentage of mono-resistance, warranting the need to strengthen control efforts.
ABSTRACT
OBJECTIVE: To describe local perceptions of blood transfusion for children with severe anaemia in Uganda. BACKGROUND: Blood transfusion is a common emergency treatment for children with severe anaemia and saves millions of lives of African children. However, the perceptions of transfusion recipients have not been well studied. A better understanding of the perceived risk may improve transfusion care. METHODS: A qualitative study based on 16 in-depth interviews of caregivers of transfused children, and six focus group discussions with community members was conducted in three regions of Uganda between October and November 2017. RESULTS: Caregivers of children and community members held blood transfusion in high regard and valued it as life-saving. However, there were widespread perceived transfusion risks, including: Human immunodeficiency virus (HIV) transmission, too rapid blood infusion and blood incompatibility. Other concerns were: fatality, changes in behaviour, donor blood being 'too strong' and use of animal blood. In contrast, recent transfusion, older age, knowledge of HIV screening of blood for transfusion, faith in God and having a critically ill child were associated with less fear about transfusion. Respondents also emphasised challenges to transfusion services access including distance to hospitals, scarcity of blood and health workers' attitudes. CONCLUSION: Perceptions of the community and caregivers of transfused children in Uganda about blood transfusion were complex: transfusion is considered life-saving but there were strong perceived transfusion risks of HIV transmission and blood incompatibility. Addressing community perceptions and facilitating access to blood transfusion represent important strategies to improve paediatric transfusion care.
Subject(s)
Anemia , Attitude to Health , Blood Safety , Blood Transfusion , Caregivers , Health Behavior , Adolescent , Adult , Age Factors , Anemia/psychology , Anemia/therapy , Child , Child, Preschool , Female , Humans , Infant , Male , Severity of Illness Index , UgandaABSTRACT
The automated high-throughput Abbott RealTime MTB real-time PCR assay has been recently launched for Mycobacterium tuberculosis complex (MTBC) clinical diagnosis. This study would like to evaluate its performance. We first compared its diagnostic performance with the Roche Cobas TaqMan MTB assay on 214 clinical respiratory specimens. Prospective analysis of a total 520 specimens was then performed to further evaluate the Abbott assay. The Abbott assay showed a lower limit of detection at 22.5 AFB/ml, which was more sensitive than the Cobas assay (167.5 AFB/ml). The two assays demonstrated a significant difference in diagnostic performance (McNemar's test; P = 0.0034), in which the Abbott assay presented significantly higher area under curve (AUC) than the Cobas assay (1.000 vs 0.880; P = 0.0002). The Abbott assay demonstrated extremely low PCR inhibition on clinical respiratory specimens. The automated Abbott assay required only very short manual handling time (0.5 h), which could help to improve the laboratory management. In the prospective analysis, the overall estimates for sensitivity and specificity of the Abbott assay were both 100 % among smear-positive specimens, whereas the smear-negative specimens were 96.7 and 96.1 %, respectively. No cross-reactivity with non-tuberculosis mycobacterial species was observed. The superiority in sensitivity of the Abbott assay for detecting MTBC in smear-negative specimens could further minimize the risk in MTBC false-negative detection. The new Abbott RealTime MTB assay has good diagnostic performance which can be a useful diagnostic tool for rapid MTBC detection in clinical laboratories.
Subject(s)
Automation, Laboratory/methods , High-Throughput Screening Assays/methods , Molecular Diagnostic Techniques/methods , Mycobacterium tuberculosis/isolation & purification , Tuberculosis, Pulmonary/diagnosis , Automation, Laboratory/instrumentation , Early Diagnosis , High-Throughput Screening Assays/instrumentation , Humans , Limit of Detection , Molecular Diagnostic Techniques/instrumentation , Prospective Studies , Real-Time Polymerase Chain Reaction , Sensitivity and Specificity , Tuberculosis, Pulmonary/microbiologyABSTRACT
We identified a predominant clone of Clostridium difficile PCR ribotype 002, which was associated with an increased sporulation frequency. In 2009, 3,528 stool samples from 2,440 patients were tested for toxigenic C. difficile in a healthcare region in Hong Kong. A total of 345 toxigenic strains from 307 (13.3%) patients were found. Ribotype 002 was the predominant ribotype, which constituted 35 samples from 29 (9.4%) patients. The mean sporulation frequency of ribotype 002 was 20.2%, which was significantly higher than that of the 56 randomly selected ribotypes other than 002 as concurrent controls (3.7%, p < 0.001). Patients carrying toxigenic ribotype 002 were more frequently admitted from an elderly home (p = 0.01) and received more ß-lactam antibiotics in the preceding 3 months compared with the controls (p = 0.04) . The identification of toxigenic ribotype 002 in 2009 was temporally related to a significant increase in both the incidence of toxigenic C. difficile from 0.53 to 0.95 per 1,000 admissions (p < 0.001) and the rate of positive detection from 4.17% to 6.28% (p < 0.001) between period 1 (2004-2008) and period 2 (2009). This finding should alert both the physician and the infection control team to the establishment of and possible outbreaks by ribotype 002 in our hospitals, as in the case of ribotype 027.
Subject(s)
Bacterial Proteins/genetics , Clostridioides difficile/classification , Clostridioides difficile/physiology , Enterocolitis, Pseudomembranous/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Proteins/metabolism , Bacterial Toxins/metabolism , Clostridioides difficile/drug effects , Clostridioides difficile/isolation & purification , Cluster Analysis , Enterotoxins/metabolism , Feces/microbiology , Female , Hong Kong/epidemiology , Humans , Incidence , Male , Middle Aged , Polymerase Chain Reaction , Ribotyping , Spores, Bacterial , Young AdultABSTRACT
B and T lymphocyte attenuator (BTLA) is an immunoglobulin superfamily member surface protein expressed on B and T cells. Its ligand, herpesvirus entry mediator (HVEM), is believed to act as a monomeric agonist that signals via the CRD1 of HVEM to inhibit lymphocyte activation: HVEM is also the receptor for lymphotoxin-α and LIGHT, which both bind in the CRD2 and CRD3 domains of the HVEM molecule, and for CD160 which competes with BTLA. We have shown that recombinant HVEM and a panel of different monoclonal antibodies specifically bind murine BTLA on both B and T cells and that some antibodies inhibit anti-CD3ε-induced T cell proliferation in vitro, but only when constrained appropriately with a putatively cross-linking reagent. The antibodies had no significant effect on in vitro T cell proliferation in a mixed lymphocyte reaction (MLR) assay nor on in vitro DO11.10 antigen-induced T cell proliferation. None of these antibodies, nor HVEM-Fc, had any significant effect on in vitro B cell proliferation induced by anti-immunoglobulin M antibodies (±anti-CD40) or lipopolysaccharide. We further elucidated the requirements for inhibition of in vitro T cell proliferation using a beads-based system to demonstrate that the antibodies that inhibited T cell proliferation in vitro were required to be presented to the T cell in a cis, and not trans, format relative to the anti-CD3ε stimulus. We also found that antibodies that inhibited T cell proliferation in vitro had no significant effect on the antibody captured interleukin-2 associated with the in vivo activation of DO11.10 T cells transferred to syngeneic recipient BALB/c mice. These data suggest that there may be specific structural requirements for the BTLA molecule to exert its effect on lymphocyte activation and proliferation.
Subject(s)
Antibodies, Monoclonal/immunology , B-Lymphocytes/immunology , Lymphocyte Activation , Receptors, Immunologic/antagonists & inhibitors , Receptors, Immunologic/immunology , T-Lymphocytes/immunology , Animals , CD3 Complex/immunology , CD40 Antigens/immunology , Cross-Linking Reagents/chemistry , Immunoglobulin M/immunology , Interleukin-2/blood , Interleukin-2/immunology , Lymphotoxin-alpha/immunology , Mice , Mice, Inbred BALB C , Receptors, Tumor Necrosis Factor, Member 14/immunologyABSTRACT
Mice with null mutations of ciliary neurotrophic factor (Cntf) receptor alpha (Cntf-Ralpha), or cytokine-like factor 1 (Clf), one component of Cntf-II (a heterodimeric Cntf-Ralpha ligand), die as neonates from motor neuron loss affecting the facial nucleus and ventral horn of the lumbar spinal cord. Exposure to cardiotrophin-like cytokine (Clc), the other putative Cntf-II element, supports motor neuron survival in vitro and in ovo. Confirmation that Clc ablation induces an equivalent phenotype to Clf deletion would support a role for Clc in the functional Cntf-II complex. In this study, Clc knockout mice had decreased facial motility, did not suckle, died within 24 hours, and had 32% and 29% fewer motor neurons in the facial nucleus and lumbar ventral horn, respectively; thus, Clc is essential for motor neuron survival during development. The concordance of the Clc knockout phenotype with those of mice lacking Cntf-Ralpha or Clf bolsters the hypothesis that Clc participates in Cntf-II.
Subject(s)
Cytokines/genetics , Cytokines/metabolism , Spinal Cord Diseases/genetics , Animals , Animals, Newborn , Mice , Mice, Knockout , Motor Neurons/pathology , Muscle, Skeletal/innervation , Spinal Cord/pathology , Spinal Cord Diseases/mortalityABSTRACT
Amorphous twisted SiO(2) nanobelts have been synthesized on Si wafers using facile thermal evaporation. These nanobelts are produced together with SiO(2) nanowires and a small quantity of SiO(2) nanosprings. Spectral and microstructural analyses suggest that the twisted SiO(2) nanobelts and nanosprings form via a polar surface driven process. Spontaneous polarization on the very thin polar crystalline SiO(2) layers on the amorphous SiO(2) nanobelt and nanospring surfaces makes the nuclei rearrange orderly and causes the nanobelt and nanowire to roll up at a certain twisty angle. The cathodoluminescence spectrum acquired from these SiO(2) nanostructures reveals three emission bands at 4.4, 3.7, and 2.7 eV originating from oxygen-related defect centers. The polar surface driven mechanism can adequately explain the growth of these novel twisty nanobelts and nanosprings which have potential applications in sensors, transducers, resonators, and photonics.
ABSTRACT
Formative research assessing human papillomavirus (HPV) vaccine readiness in Uganda was conducted in 2007. The objective was to generate evidence for government decision-making and operational planning for HPV vaccine introduction. Qualitative research methods with children, parents, teachers, community leaders, health workers, technical experts and political leaders were used to capture understanding of socio-cultural, health system and policy environments. We found low levels of knowledge about cervical cancer and HPV. Vaccination and its benefits were well-understood; respondents were positive about HPV vaccination. Health systems were deemed adequate for HPV vaccine delivery. Schools were identified as a vaccination venue, given high attendance by girls aged 10-12 years. Communication and advocacy strategies to foster acceptance should provide information on cervical cancer, HPV vaccine safety, and side effects. Policymakers requested further detail on costs. Introduction of HPV vaccine could be integrated into existing reproductive health and immunization policies.
Subject(s)
Papillomavirus Infections/prevention & control , Papillomavirus Vaccines , Preventive Health Services/organization & administration , Child , Female , Humans , Patient Acceptance of Health Care , UgandaABSTRACT
We conducted a prospective, descriptive study in the Clinica Anglo Americana, a prívate institution taking care of patients from a medium-high socioeconomic level in Lima. The goal of the study was to determine the frequency of histologic findings in liver biopsies performed by laparoscopy or percutaneously in patients with overweight (body mass index > 25 kg/m2) or obesity (body mass index > 30 kg/m2), and to evaluate the correlation with antropometric variables such as BMI, waist circumference, history of diabetes or hyperlypidemia, and biochemical variables like glycemia, lipid profile, aminotransferases and AST/ALT ratio. Between the years 2001 and 2006 50 patients were biopsied, 29 with overweight and 21 with obesity. Eighteen had simple steatosis and 22 had Non-alcoholic steatohepatitis (NASH) (44%), so 40 patients (80%) had some form of fatty liver. Five patients (10%) had cirrhosis confirmed by biopsy, and in all of them the finding of cirrhosis was completely incidental. Sixty four percent of patients with NASH were obese, like the 5 cirrhotics in our series. Herein we illustrate that in a relatively small sample of patients with obesity and overweight like ours, we found all the forms of the liver steatosis spectrum, from simple steatosis to cirrhosis, with a high frequency of NASH.
Subject(s)
Liver Diseases/complications , Liver Diseases/pathology , Obesity/complications , Adult , Aged , Female , Humans , Liver Diseases/epidemiology , Liver Diseases/metabolism , Male , Middle Aged , Obesity/metabolism , Overweight/complications , Overweight/metabolism , Peru , Prevalence , Prospective Studies , Young AdultABSTRACT
Efficient resonant electron transfer from the surface bonding structure to the conduction band of quantum confined Si nanocrystals is observed by Si nanocrystals in a toluene suspension. Based on the electron transfer mechanism, the enhancement of photoluminescence originates from the band-to-band recombination in the p-type Si nanocrystals suspended in a toluene solution. The energy levels of the electrons in the Si nanocrystals chemisorbed with toluene molecules are calculated using the method of linear combination of atomic orbitals, and the characteristics of the obtained density of states is in good agreement with the observed photoluminescence properties.
ABSTRACT
111-oriented p-type Si wafer with a resistivity of 1-5 Omega cm was implanted with Fe+ and then annealed at 1100 degrees C in N2 for 60 min, followed by anodization in a solution of HF to form porous structure with beta-FeSi2 nanocrystallites. Photoluminescence (PL) spectral measurements show that a strong PL peak appears in the range of 610-670 nm. The position of the PL peak remains unchanged, but its intensity increases with the storage time in air until about three months and then saturates. C60 molecules were chemically coupled on the porous structure through a kind of silane coupling agent to form a nanocomposite. It is revealed that the stable PL peak monotonically shifts to a pinning wavelength at 570 nm. Experimental results from PL, PL excitation, Raman scattering, and x-ray diffraction measurements clearly show that the pinned PL originates from optical transition in C60-related defect states, whereas the photoexcited carriers occur in the beta-FeSi2 nanocrystallites formed during anodization. This work opens a new way to tailor nanometer environment for seeking optimal luminescent properties.
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Photoluminescence (PL) measurements have been performed on the nanocomposites of higher fullerene-coupled porous silicon (PS) nanocrystals. For the C70PS and C76(78)PS nanocomposites, the PL spectra show a pinning wavelength at approximately 565 nm and for the C84PS and C94PS nanosystems the pinning wavelength is at approximately 590 nm. The PL pinning property is closely related to the sorts of the coupled fullerenes. A band mixing model of direct and indirect gaps in a nanometer environment consisting of nc-Si core, SiO2 surface layer, and coupled fullerene has been proposed for calculation of electronic states. Good agreement is achieved between the experiments and theory.
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Using electrochemical etching of a polycrystalline 3C-SiC target and subsequent ultrasonic treatment in water solution, we have fabricated suspensions of 3C-SiC nanocrystallites that luminesce. Transmission electron microscope observations show that the 3C-SiC nanocrystallites, which uniformly disperse in water, have sizes in the range of 1-6 nm. Photoluminescence and photoluminescence excitation spectral examinations show clear evidence for the quantum confinement of 3C-SiC nanocrystallites with the emission band maximum ranging from 440 to 560 nm. Tunable, composite polystyrene/SiC film can be made by adding polystyrene to a toluene suspension of the 3C-SiC nanocrystallites and then coating the resulting solution onto a Si wafer.
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A uniquely structured SiO(x)-capped (x = 0.5-0.8) Si nanowire array with strong blue emission, like a nanobeacon array, was fabricated using electroless metal (silver) deposition on a water plasma-treated Si wafer. Formation of the nanoscale light source array can be understood on the basis of a self-assembled localized microscopic electrochemical cell model and a diffusion-limited aggregation process. Photoluminescence spectral analysis reveals that the intensity of the broad blue-emitting luminescent band centred at around 435 nm strongly depends upon the irradiation of H(2)O(+), HO(+), and O(+) ions, which are present in the water plasma. We attribute the blue PL band to the optical transition of the self-trapped excitons at the surfaces of SiO(x) nanocaps.
ABSTRACT
Using C60 molecule as a kind of surface-passivated agent to modify the electronic structure of Si nanocrystallites in porous silicon, we disclose that this kind of C60/nanocrystalline Si coupling system can show a strong blue emission at approximately 460 nm when stored in air for more than one year. After a full characterization of the photoluminescence properties, we propose a luminescent center in the SiOx layer at the surface of a Si nanocrystallite. It is a pair consisting of an oxygen vacancy and an interstitial oxygen. The interstitial oxygen also forms a peroxy linkage with a neighboring lattice oxygen. Radiative recombination of carriers photogenerated from Si nanocrystallite cores in the luminescent centers results in the observed blue photoluminescence. Neutron irradiation experiments support our assignment of the blue emission mechanism. This work improves the understanding of the origin of blue emission from silicon/oxygen-related nanostructured materials.
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Four groups of Si nanostructures with and without beta-SiC nanocrystals were fabricated for clarifying the origin of a blue emission with a double-peak structure at 417 and 436 nm. Spectral analyses and microstructural observations show that the blue emission is related to the existence of excess Si atoms in these Si nanostructures. The energy levels of electrons in Si nanocrystals with vacancy defects formed from the excess Si atoms are calculated and the characteristics of the obtained density of states coincide with the observed double-peak emission. The present work provides a possible mechanism of the blue emission in various Si nanostructures.