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A copolymer termed HASL produced from monomeric units of 2-acrylamido-2-methyl-1-(5-methylhydantoinyl)propane (HA) and of 3-(trimethoxysilyl)propyl methacrylate (SL) has been coated onto stainless steel and Inconel™ substrates, which upon halogenation with either aqueous oxidative chlorine or bromine, became antimicrobial. It has been demonstrated that the halogenated stainless steel and Inconel™ substrates were effective in producing 6 to 7 log inactivations of Staphylococcus aureus and Escherichia coli O157:H7 within about 10 min, and in prevention of Pseudomonas aeruginosa biofilm formation over a period of at least 72 h on the stainless steel substrates. Upon loss of halogen, the HASL coating could be re-charged with aqueous halogen. The HASL coating was easily applied to the substrates via a simple dip-coating method and was reasonably stable to contact with water. Both chlorinated substrates could be loaded with at least 6 × 1016 oxidative Cl atoms per cm2 and maintained a loading of greater than 1 × 1016 chlorine atoms per cm2 for a period of 3-7 days while agitated in aqueous solution. After loss of chlorine to a level below 1 × 1016 atoms per cm2, the substrates could be recharged to the 6 × 1016 Cl atoms per cm2 level for at least 5 times over a 28 day period. The new antimicrobial coating technology has potential for use in a variety of important applications, particularly for water treatment and storage on spacecraft.
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The purpose of this study is to assess the differences in VFA diagnostic accuracy when using bilateral decubitus views and whether diagnostic accuracy is affected by scoliosis. Our findings show that the current practice of performing only one side is valid; however, bilateral views can improve specificity in scoliosis. INTRODUCTION: The diagnostic accuracy of vertebral fracture assessment (VFA) can be influenced by poor patient position and scoliosis. This study aims to assess the differences in VFA diagnostic accuracy for right and left lateral decubitus views and the effect of scoliosis. METHODS: One hundred fourteen postmenopausal women received right and left lateral thoracolumbar spine dual-energy VFA and radiography. Cobb angles were measured from the posteroanterior absorptiometry image, and lumbar spine radiography was the standard reference for vertebral fracture and also provides the levels investigated. McNemar's test was used to compare accuracy between the two decubitus position and Fisher's exact test was used for patients with and without scoliosis. RESULTS: Forty-two vertebral fractures (VFs) were identified. There was no significant difference in sensitivity (p = 0.125) or specificity (p = 0.866) between the left lateral decubitus (64.3, 97.2%) and right lateral decubitus (76.2, 91.1%), respectively, views. Scoliotic patients had a significantly worse specificity (92.7 vs 98.1%, p = 0.003) than patients without scoliosis; however, a combination of both decubitus positions significantly improved specificity (p < 0.001). CONCLUSION: Right and left side lateral decubitus views have excellent agreement with radiography and similar diagnostic accuracy in the detection of VFs. Thus, the current practice of performing only one side is valid. With scoliosis, bilateral decubitus views can improve the specificity of detecting VF; however, this would increase radiation dose.
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Fraturas por Compressão/diagnóstico por imagem , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas por Compressão/complicações , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/lesões , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/diagnóstico por imagem , Fraturas por Osteoporose/complicações , Radiografia/métodos , Escoliose/complicações , Escoliose/diagnóstico por imagem , Sensibilidade e Especificidade , Fraturas da Coluna Vertebral/complicaçõesRESUMO
OBJECTIVES: The study aimed to determine the long-term Staphylococcus aureus colonization patterns and strain relatedness, and the association between maternal and infant colonization in infancy. METHODS: A birth cohort study was conducted from January 2012 to November 2014. Nasopharyngeal swabs for S. aureus detection were collected from infants at the age of 1, 2, 4, 6 and 12 months and from mothers when their children were 1-month-old. RESULTS: In total, 254 samples were collected at each planned visit during the first 12-month study. The prevalence of S. aureus colonization decreased in the first year of life, ranging from 61.0% (155/254) at the age of 1 month to 12.2% (31/254) at 12 months. Persistent colonization, defined as a positive culture on four or five occasions, was detected in only 13.8% (35/254) of carriers. Most of the persistent carriers were colonized with methicillin-resistant S. aureus (MRSA) only, and among persistent MRSA carriers, 61.1% (11/18) had indistinguishable genotypes. Of the mothers with MRSA colonization, 77.1% (27/35) had infants who were concomitantly colonized at the age of 1 month; 70.4% (19/27) of the infant-mother paired isolates belonged to indistinguishable or related subtypes, which suggests that surrounding carriers, probably their mothers, may be the possible source for MRSA acquisition in early infancy. CONCLUSIONS: Staphylococcus aureus colonization including MRSA was commonly observed in our cohort. Strains of persistent MRSA among infant-mother pairs were usually of indistinguishable genotypes. Therefore, horizontal spread within households is possibly an important factor related to infant MRSA colonization.
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Portador Sadio , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Nasofaringe/microbiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Estudos de Coortes , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/genética , Tipagem Molecular , Razão de Chances , Taiwan/epidemiologiaRESUMO
We assessed the incidence of hip fracture and second hip fractures in Taiwan from 2001 to 2012. Age-standardized incidence rates decreased after 2005. However, mortality rate after first hip fracture was substantial compared to second hip fracture rate in a competing risk model. INTRODUCTION: The aim of the study is to assess the incidence rates (IRs) of hip fractures, including changes in trends and medical costs, and second hip fractures in the Taiwanese population. METHODS: The number of hip fractures and the associated medical costs were obtained from the annual report of the Ministry of Health and Welfare, Taiwan, for individuals ≥50 years of age. The data of population at risk were retrieved from annual population reports from the Ministry of the Interior, Taiwan. The incidence of second hip fractures was evaluated from the National Health Insurance Research Database of Taiwan for insured individuals aged ≥50 years from 2001 to 2011 with follow-up until 2013 using a competing risk model. RESULTS: The IR for the entire population increased from 332.7 to 336.5 per 100,000 person-years during 2001-2005 and decreased thereafter. This secular change was driven by a decrease in hip fractures for both men and women. The 10-year cumulative incidence rate of second hip fracture was 11.2% (95% CI 11.0-11.5%) in women and 7.9% (95% CI 7.6-8.1%) in men. Adjusted by consumer price index (CPI), the costs of hospitalization due to hip fracture increased from NTD 1.17 billion in 2001 to NTD 1.43 billion in 2012. However, the CPI-adjusted costs of each admission decreased from NTD 74944 in 2001 to NTD 65791 in 2012. CONCLUSIONS: Since 2006, the IR of hip fractures has been declining in Taiwan. The 10-year cumulative IR of mortality is substantial for individuals who with first hip fracture.
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Fraturas do Quadril/epidemiologia , Fraturas por Osteoporose/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Custos de Cuidados de Saúde/tendências , Fraturas do Quadril/economia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/economia , Recidiva , Distribuição por Sexo , Taiwan/epidemiologiaRESUMO
AIMS: Public controversy regarding the potential overdiagnosis and overmedication of children with attention-deficit/hyperactivity disorder (ADHD) has continued for decades. This study used the National Health Insurance Research Database of Taiwan (NHIRD-TW) to explore trends in ADHD diagnosis in youths and the proportion of those receiving medication, with the aim of determining whether ADHD is overdiagnosed and overmedicated in Taiwan. METHOD: Youths (age ≤18 years) who had at least two NHIRD-TW claims records with ADHD diagnosis between January 2000 and December 2011 were selected as the subject cohort. In total, the study sample comprised 145 018 patients with ADHD (mean age at a diagnosis of ADHD: 7.7 ± 3.1 years; 21.4% females). The number of cases of ADHD were calculated annually for each year (from 2000 to 2011), and the number of cases per year who received medication was determined as those with at least one record of pharmacotherapy (immediate-release methylphenidate, osmotic controlled-release formulation of methylphenidate, and atomoxetine) in each year. RESULTS: The prevalence rates of a diagnosis of ADHD in the youths ranged from 0.11% in 2000 to 1.24% in 2011. Compared with children under 6 years of age, the ADHD diagnosis rates in children aged between 7 and 12 years (ratio of prevalence rates = 4.36) and in those aged between 13 and 18 years (ratio of prevalence rates = 1.42) were significantly higher during the study period. The prevalence in males was higher than that in females (ratio of prevalence rates = 4.09). Among the youths with ADHD, 50.2% received medications in 2000 compared with 61.0% in 2011. The probability of receiving ADHD medication increased with age. More male ADHD patients received medications that females patients (ratio of prevalence rates = 1.16). CONCLUSIONS: The rate of ADHD diagnosis was far lower than the prevalence rate (7.5%) identified in a previous community study using face-to-face interviews. Approximately 40-50% of the youths with ADHD did not receive any medications. These findings are not consistent with a systematic public opinion about overdiagnosis or overmedication of ADHD in Taiwan.
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Inibidores da Captação Adrenérgica/uso terapêutico , Cloridrato de Atomoxetina/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Uso Excessivo dos Serviços de Saúde/estatística & dados numéricos , Metilfenidato/uso terapêutico , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Vigilância da População , Prevalência , Taiwan/epidemiologiaRESUMO
Deafness or hearing loss is a major issue in human health. Inner ear hair cells are the main sensory receptors responsible for hearing. Defects in hair cells are one of the major causes of deafness. A combination of induced pluripotent stem cell (iPSC) technology with genome-editing technology may provide an attractive cell-based strategy to regenerate hair cells and treat hereditary deafness in humans. Here, we report the generation of iPSCs from members of a Chinese family carrying MYO15A c.4642G>A and c.8374G>A mutations and the induction of hair cell-like cells from those iPSCs. The compound heterozygous MYO15A mutations resulted in abnormal morphology and dysfunction of the derived hair cell-like cells. We used a CRISPR/Cas9 approach to genetically correct the MYO15A mutation in the iPSCs and rescued the morphology and function of the derived hair cell-like cells. Our data demonstrate the feasibility of generating inner ear hair cells from human iPSCs and the functional rescue of gene mutation-based deafness by using genetic correction.
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Células Ciliadas Auditivas Internas/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Miosinas/genética , Sequência de Bases , Sistemas CRISPR-Cas/genética , Diferenciação Celular , Reprogramação Celular , Pré-Escolar , Derme/citologia , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo , Células Ciliadas Auditivas Internas/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Mutação , Miosinas/metabolismo , Fator de Transcrição PAX2/genética , Fator de Transcrição PAX2/metabolismo , Fator de Transcrição PAX8/genética , Fator de Transcrição PAX8/metabolismo , Linhagem , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
N-Halamine antibacterial materials have superior inactivation activities due to oxidative chlorine species. However, N-Cl bonds and bonds between N-halamine and substrates often decompose rapidly under UV irradiation, leading to unrecoverable loss of antimicrobial activity. In this study, titanium dioxide was covalently bonded onto N-halamine siloxane poly[5,5-dimethyl-3-(3'-triethoxysilylpropyl)hydantoin] (PSPH) via a sol-gel process. Experimental testing of the chlorinated cotton fabrics treated with TiO2/PSPH demonstrated that the residual oxidative chlorine in cotton-TiO2/PSPH-Cl was still effective for inactivating bacteria after 50 washing cycles and under UV light irradiation for 24 h. Quantum mechanical calculations found that TiO2 improves the UV stability of the PSPH-Cl system by increasing the activation barrier of the C-Si scission reaction responsible for the loss of the biocidal hydantoin moiety. SEM, XPS and FTIR spectra were used to characterize the coated cotton samples. Cotton-TiO2/PSPH-Cl samples exhibited good antibacterial activity against Staphylococcus aureus (ATCC 6538) and Escherichia coli O157:H7 (ATCC 43895). The storage stability and washing stability of treated cotton fabrics were also investigated.
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Antibacterianos/química , Infecções Bacterianas/prevenção & controle , Materiais Revestidos Biocompatíveis/química , Siloxanas/química , Titânio/química , Antibacterianos/farmacologia , Antibacterianos/efeitos da radiação , Materiais Revestidos Biocompatíveis/efeitos da radiação , Materiais Revestidos Biocompatíveis/uso terapêutico , Fibra de Algodão , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/patogenicidade , Humanos , Hidantoínas/química , Fotólise , Siloxanas/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Têxteis/microbiologia , Titânio/uso terapêutico , Raios UltravioletaRESUMO
BACKGROUND: The rapid diagnosis of tuberculosis (TB) by detecting and identifying Mycobacterium tuberculosis complex (MTC) in clinical culture isolates can be achieved by a combination of rapid tests. OBJECTIVE: To propose a cost-effective laboratory protocol for MTC identification. DESIGN: MTC (n = 278) was identified using microscopic morphology, two immunochromatographic assays (ICAs) (Tibilia™ and MeDiPro(®) M. tuberculosis Antigen Rapid Test) and the strand displacement amplification (SDA) method (ProbeTec), and the results were compared. RESULTS: Microscopic morphology (cord-like) had a sensitivity of 99.3%, a specificity of 84.3%, a positive predictive value (PPV) of 88.2% and a negative predictive value (NPV) of 99.1%. The overall sensitivity/specificity of the Tibilia, MeDiPro and ProbeTec assays were respectively 98.7%/98.4%, 88.0%/85.2% and 97.4%/98.4%. The PPV/NPV for Tibilia, MeDiPro and ProbeTec were respectively 98.7%/98.4%, 87.4%/85.8% and 98.7%/96.8%. Cord-like microscopy was the least expensive method and could be used for the identification of MTC. ICA offers cost-effective screening compared to the SDA method. Tibilia performed better than MeDiPro, while its diagnostic value was similar to the SDA method. CONCLUSION: We recommend a combination of microscopic morphology and Tibilia to further improve the sensitivity and PPV of MTC identification at lower cost.
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Cromatografia de Afinidade/métodos , Microscopia/métodos , Mycobacterium tuberculosis/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Tuberculose/diagnóstico , Cromatografia de Afinidade/economia , Análise Custo-Benefício , Humanos , Microscopia/economia , Técnicas de Amplificação de Ácido Nucleico/economia , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Tuberculose/microbiologiaRESUMO
In this research, two N-halamine polymer precursors, a cationic homopolymer poly((3-acrylamidopropyl)trimethylammonium chloride) (CHP) and an anionic homopolymer poly(2-acrylamido-2-methylpropane sulfonic acid sodium salt) (AHP), have been successfully synthesized and coated onto cotton fabrics via a layer-by-layer (LbL) deposition technique. The coated cotton fabrics were characterized using scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The biocidal efficacies of uncoated and coated cotton fabrics were evaluated against Staphylococcus aureus and Escherichia coli. The chlorinated swatches (CHP-Cl and AHP-Cl) inactivated 100% S. aureus and 99.73% E. coli O157:H7 in 30 min. Over 51% of the chlorine is retained after the equivalent of 50 machine washes. A skin stimulation test showed that CHP-Cl and AHP-Cl compounds have no irritation to rabbit skin, and so these swatches might be utilized for biomedical applications in the future. As an easy and efficient way of coating fabrics, the LbL deposition technique can broaden the use of N-halamine biocides in other polar substances as antimicrobial functional coatings.
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The efficacy of adjuvant interferon treatment for the management of patients with viral hepatitis-related hepatocellular carcinoma (HCC) following curative treatment is controversial. We have conducted a systematic review with meta-analysis to assess the effects of adjuvant interferon therapy on survival outcomes. Randomized and nonrandomized studies (NRSs) comparing adjuvant interferon treatment with the standard of care for viral hepatitis-related HCC after curative treatment were included. CENTRAL, Medline, EMBASE and the Science Citation Index were searched with complementary manual searches. The primary outcomes were recurrence-free survival (RFS) and overall survival (OS). Nine randomized trials and 13 NRSs were included in the meta-analysis. These nine randomized trials included 942 participants, of whom, 490 were randomized to the adjuvant interferon treatment group and 452 to the control group. The results of meta-analysis showed unexplained heterogeneity for both RFS and OS. The 13 NRSs included 2214 participants, of whom, 493 were assigned to the adjuvant interferon treatment group and 1721 to the control group. The results of meta-analysis showed that, compared with controls, adjuvant interferon treatment significantly improved the RFS [hazard ratio (HR) 0.66, 95% confidence interval (CI) 0.52-0.84, I(2) = 29%] and OS (HR 0.43, 95% CI 0.34-0.56, I(2) = 0%) of patients with hepatitis C virus-related HCC following curative treatment. There was little evidence for beneficial effects on patients with hepatitis B virus-related HCC. Future research should be aimed at clarifying whether the effects of adjuvant interferon therapy are more prominent in hepatitis C patients with sustained virological responses.
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Carcinoma Hepatocelular/tratamento farmacológico , Hepatite B/complicações , Hepatite C/complicações , Fatores Imunológicos/uso terapêutico , Interferons/uso terapêutico , Carcinoma Hepatocelular/cirurgia , Humanos , Análise de Sobrevida , Resultado do TratamentoRESUMO
The inherent antimicrobial properties and biodegradability of chitosan make it an ideal candidate for antimicrobial materials. In this study, N-halamine precursor 3-glycidyl-5,5-dimethylhydantoin (GH) was synthesized and bonded onto chitosan by a ring opening reaction between chitosan and GH. The chitosan film modified with the N-halamine precursor could be rendered biocidal after exposure to a dilute household bleach solution. Syntheses routes, characterization data, and antimicrobial test results are presented. The chlorinated films with 2.60 × 10(18) atoms/cm(2) of active chlorine were challenged with Staphylococcus aureus (ATCC 6538) and Escherichia coli O157:H7 (ATCC 43895) and showed good efficacy against these two bacterial species with log reductions of 7.4 and 7.5 within 10 and 5 min of contact time, respectively. These films may serve as potential materials for food packaging and biomedical applications.
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Quitosana , Hidantoínas/química , Polímeros , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Materiais Revestidos Biocompatíveis , Escherichia coli O157/efeitos dos fármacos , Hidantoínas/síntese química , Hidantoínas/farmacologia , Polímeros/síntese química , Polímeros/química , Polímeros/farmacologia , Staphylococcus aureus/efeitos dos fármacosRESUMO
An array of 32 Mirnov coils with novel features of high sensitivity and low noise has been installed on the outside chamber surface of Prairie View rotamak. This B(R)-oriented coil array has proven to be very reliable in the plasma driven by rotating magnetic field; it can resolve magnetic perturbation signals of 0.1 G. With this new diagnostic, the n = 1 tilt, radial shift, and kink modes are observed for the first time in rotamak plasmas.
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Methylmercury (MeHg) is a ubiquitous environmental contaminant which bioaccumulates in marine biota. Fish constitute an important part of a balanced human diet contributing with health beneficial nutrients but may also contain contaminants such as MeHg. Interactions between the marine n-3 fatty acids eicosapentaenoic acid (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA) with MeHg-induced toxicity were investigated. Different toxic and metabolic responses were studied in Atlantic salmon kidney (ASK) cell line and the mammalian kidney-derived HEK293 cell line. Both cell lines were preincubated with DHA or EPA prior to MeHg-exposure, and cell toxicity was assessed differently in the cell lines by MeHg-uptake in cells (ASK and HEK293), proliferation (HEK293 and ASK), apoptosis (ASK), oxidation of the red-ox probe roGFP (HEK293), and regulation of selected toxicological and metabolic transcriptional markers (ASK). DHA was observed to decrease the uptake of MeHg in HEK293, but not in ASK cells. DHA also increased, while EPA decreased, MeHg-induced apoptosis in ASK. MeHg exposure induced changes in selected metabolic and known MeHg biomarkers in ASK cells. Both DHA and MeHg, but not EPA, oxidized roGFP in HEK293 cells. In conclusion, marine n-3 fatty acids may ameliorate MeHg toxicity, either by decreasing apoptosis (EPA) or by reducing MeHg uptake (DHA). However, DHA can also augment MeHg toxicity by increasing oxidative stress and apoptosis when combined with MeHg.
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Ácidos Graxos Ômega-3/farmacologia , Compostos de Metilmercúrio/toxicidade , Análise de Variância , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Peróxido de Hidrogênio , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Proteínas/genética , Proteínas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , SalmãoRESUMO
This paper details the authors' efforts to push the baseline of emotion recognition performance on the Geneva Multimodal Emotion Portrayals (GEMEP) Facial Expression Recognition and Analysis database. Both subject-dependent and subject-independent emotion recognition scenarios are addressed in this paper. The approach toward solving this problem involves face detection, followed by key-point identification, then feature generation, and then, finally, classification. An ensemble of features consisting of hierarchical Gaussianization, scale-invariant feature transform, and some coarse motion features have been used. In the classification stage, we used support vector machines. The classification task has been divided into person-specific and person-independent emotion recognitions using face recognition with either manual labels or automatic algorithms. We achieve 100% performance for the person-specific one, 66% performance for the person-independent one, and 80% performance for overall results, in terms of classification rate, for emotion recognition with manual identification of subjects.
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A series of copolymers containing units of a novel hydantoinylacrylamide and the sodium salt of 2-(acrylamido)-2-methylpropanesulfonic acid have been synthesized. The homopolymer of the hydantoinylacrylamide compound was insoluble in water, while the copolymers with the sulfonic acid sodium salt were water-dispersible/soluble, with the solution becoming completely transparent when the feed ratio for the copolymer contained 7 parts of the hydantoin moiety to 3 parts of the sodium sulfonate moiety. The polymers were added into a commercial water-based latex paint, and upon drying, the painted surfaces treated with the water-miscible copolymers were rendered antimicrobial following chlorination with dilute household bleach. The chlorinated homopolymer failed to provide an antimicrobial property for the paint because of its tendency to isolate into aggregates in the paint, while the completely miscible copolymers were capable of 6-log inactivation of Staphylococcus aureus and Escherichia coli O157:H7 within 5 min of contact time.
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Aminas/química , Anti-Infecciosos/química , Pintura , Polímeros/química , Aminas/farmacologia , Anti-Infecciosos/farmacologia , Cloro/química , Escherichia coli O157/efeitos dos fármacos , Polímeros/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Ácidos Sulfônicos/química , Água/químicaRESUMO
A new N-halamine copolymer has been prepared, characterized, and evaluated for antimicrobial efficacy, stability toward hydrolyses, and stability toward UVA degradation when covalently bound to cellulose fibers. A copolymer of 3-chloro-2-hydroxypropylmethacrylate and glycidyl methacrylate was coated onto cotton, and, after curing, was treated with an aqueous solution containing the potassium salt of 5,5-dimethylhydantoin to form a coating which became antimicrobial upon exposure to househod bleach (sodium hypochlorite). The coating inactivated S. aureus and E. coli O157:H7 within minutes of contact time and was quite stable toward washing and UVA photodegradation.
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Aminas/química , Anti-Infecciosos/química , Compostos de Epóxi/química , Halogênios/química , Polímeros/química , Anti-Infecciosos/farmacologia , Celulose/química , Compostos de Epóxi/farmacologia , Escherichia coli O157/efeitos dos fármacos , Metacrilatos/química , Fotólise , Polímeros/síntese química , Polímeros/farmacologia , Hipoclorito de Sódio/química , Staphylococcus aureus/efeitos dos fármacos , Raios UltravioletaRESUMO
Two N-halamine copolymer precursors, poly(2,2,6,6-tetramethyl-4-piperidyl methacrylate-co-acrylic acid potassium salt) and poly(2,2,6,6-tetramethyl-4-piperidyl methacrylate-co-trimethyl-2-methacryloxyethylammonium chloride) have been synthesized and successfully coated onto cotton fabric via a layer-by-layer (LbL) assembly technique. A multilayer thin film was deposited onto the fiber surfaces by alternative exposure to polyelectrolyte solutions. The coating was rendered biocidal by a dilute household bleach treatment. The biocidal efficacies of tested swatches composed of treated fibers were evaluated against Staphylococcus aureus and Escherichia coli. It was determined that chlorinated samples inactivated both S. aureus and E. coli O157:H7 within 15 min of contact time, whereas the unchlorinated control samples did not exhibit significant biocidal activities. Stabilities of the coatings toward washing and ultraviolet light exposure have also been studied. It was found that the stability toward washing was superior, whereas the UVA light stability was moderate compared to previously studied N-halamine moieties. The layer-by-layer assembly technique can be used to attach N-halamine precursor polymers onto cellulose surfaces without using covalently bonding tethering groups which limit the structure designs. In addition, ionic precursors are very soluble in water, thus promising for biocidal coatings without the use of organic solvents.
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Desinfetantes/química , Desinfetantes/farmacologia , Polímeros/química , Escherichia coli/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Estrutura Molecular , Polímeros/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacosRESUMO
The cost-effectiveness of the ProbeTec ET Direct TB assay (DTB) was compared with that of culture for detection of Mycobacterium tuberculosis complex in 361 acid-fast stain-positive respiratory specimens. The overall sensitivity, specificity, positive predictive value and negative predictive value of DTB were 97.7%, 86.6%, 87.2% and 97.6%, respectively. When clinical evaluation was added to DTB, the specificity and positive predictive value of DTB increased to 94.7% and 95.4%, respectively. Treatment costs of $133,521 would have been saved in this cohort if DTB, instead of culture results, had been used to eliminate 'false-positive' smear results.
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Técnicas de Diagnóstico Molecular/economia , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/genética , Kit de Reagentes para Diagnóstico/economia , Tuberculose/diagnóstico , Reações Falso-Positivas , Humanos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/tratamento farmacológico , Tuberculose/microbiologiaRESUMO
The Beijing genotype of Mycobacterium tuberculosis is an endemic lineage in East Asia that has disseminated worldwide. It is a major health concern, as it is geographically widespread and is considered to be hypervirulent. To elucidate its genetic diversity in Taiwan, phylogenetic reconstruction was performed using 338 M. tuberculosis Beijing family clinical isolates. Region-of-difference analysis revealed the strains from Taiwan to be distributed among six subgroups of a phylogenetic tree. Synonymous single nucleotide polymorphisms at 10 chromosomal positions were also analysed. Among the 338 isolates analysed for single-nucleotide polymorphisms by using mass spectrometry, the most frequent strain found was ST10 (53.3%), followed by ST19 (14.8%) and ST22 (14.5%). Tests of drug resistance showed that the sublineages ST10, ST19 and ST26 were over-represented in the multidrug-resistant population. The presence of mutations in putative genes coding for DNA repair enzymes, which could confer a mutator phenotype to facilitate spreading of the pathogen, did not demonstrate an association with multidrug resistance. Therefore, the DNA repair genes may be involved in transmission but not in drug resistance.
Assuntos
Genes Bacterianos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Análise por Conglomerados , DNA Bacteriano/análise , Genótipo , Humanos , Mycobacterium tuberculosis/patogenicidade , Filogenia , Polimorfismo de Nucleotídeo Único , TaiwanRESUMO
SETTING: A referral hospital in Kaohsiung, Taiwan. OBJECTIVE: To evaluate the impact of an in-hospital tuberculosis (TB) quality care programme initiated in May 2005 on health provider delay and outcome of newly diagnosed TB cases. DESIGN: Retrospective chart review of newly diagnosed TB cases presenting in 2002 and 2006. Health provider delay, clinical manifestations, management and outcome were recorded. RESULTS: Overall, 327 patients before (2002) and 262 patients after (2006) the programme began were enrolled. Patients were older men (mean age 65.9 years) and 23.4% (138/589) had diabetes; 84.4% had received anti-tuberculosis treatment. The programme shortened the time for doctors to order a chest X-ray (P < 0.01), and the reporting time for smear (P < 0.0001) and culture (P < 0.0001). On multivariable analysis, risk factors for attributable mortality included age >/=65 years (OR 4.4, 95%CI 1.8-10.9, P = 0.001) and liver cirrhosis (OR 4.3, 95%CI 1.1-16.6, P = 0.04). Treatment reduced mortality by 81% (OR 0.2, 95%CI 0.1-0.4, P < 0.001) and the programme halved overall mortality (OR 0.5, 95%CI 0.3-0.8, P = 0.01), and reduced attributable mortality by 62% (OR 0.4, 95%CI 0.2-0.8, P < 0.01). CONCLUSION: Intervention at the hospital level for quality control of TB care was instrumental in reducing health provider delay and led to a significant reduction in mortality.