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1.
Pharm Res ; 40(1): 197-213, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36376605

RESUMO

PURPOSE: Asiatic acid (AA) is reported for its neuroprotective potential in Alzheimer's disease (AD). This present work aimed to develop AA loaded nanostructured lipid carriers (AAN) for targeting the delivery of AA into the brain and ameliorating the cognitive deficits in AD rats. METHODS: AAN was optimized using the Box-Behnken design, considering 3 factors (soya lecithin, tween 80, and high pressure homogenizer (HPH) pressure) as independent variables while particle size (PS), zeta potential (ZP) and entrapment efficiency (EE) were dependent variables. Cytotoxicity assay and internalization studies of AAN were evaluated in SH-SY5Y cells and further neuroprotective efficiency on intracellular amyloid beta (Aß) aggregation was evaluated in Aß 1-42 treated cells with thioflavin T (ThT). The behavioral acquisition effects were evaluated in Aß 1-42 (5 µg/ 5 µL, intracerebroventricular (ICV), unilateral) induced AD model followed by the histology and quantification of neurotransmitters levels. RESULTS: The optimized AAN revealed desired PS (44.1 ± 12.4 nm), ZP (- 47.1 ± 0.017 mv) and EE (73.41 ± 2.53%) for brain targeting delivery of AA. In-vitro, AAN exhibited better neuroprotective potential than AA suspension (AAS). AA content was 1.28 folds and 2.99 folds heightened in plasma and brain respectively after the i.p. administration of AAN as compared to AAS. The results of pharmacodynamic studies manifested the AAN treatment significantly (p < 0.05) ameliorated the cognitive deficits. CONCLUSIONS: Hence, developed AAN has neuroprotective potential and should be further considered as an unconventional platform in preclinical model for the management of AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Neuroblastoma , Fármacos Neuroprotetores , Humanos , Ratos , Animais , Peptídeos beta-Amiloides/metabolismo , Neuroblastoma/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/patologia , Estresse Oxidativo , Colinesterases , Fármacos Neuroprotetores/farmacologia
2.
Epidemiol Infect ; 151: e171, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37750016

RESUMO

In this short report, we describe an outbreak of COVID-19 caused by Omicron subvariant BA.5.2.1 in highly vaccinated patients in a respiratory ward in a large acute general hospital in North West London, United Kingdom. The attack rate was high (14/33 (42%)) but the clinical impact was relatively non-severe including in patients who were at high risk of severe COVID-19. Twelve of fourteen patients had COVID-19 vaccinations. There was only one death due to COVID-19 pneumonitis. The findings of this outbreak investigation suggest that while the transmissibility of Omicron BA.5.2.1 subvariant is high, infections caused by this strain are non-severe in vaccinated patients, even if they are at high risk of severe COVID-19 infection.


Assuntos
COVID-19 , Infecção Hospitalar , Humanos , SARS-CoV-2 , Infecção Hospitalar/epidemiologia , COVID-19/epidemiologia , Hospitais Gerais , Surtos de Doenças
3.
Dig Dis Sci ; 68(5): 2023-2029, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36357596

RESUMO

AIM/OBJECTIVE: Quantitative fecal immunochemical tests (FIT) were recommended by NICE for patients in primary care presenting with low-risk symptoms of colorectal cancer (CRC). FIT is more accurate in the detection of CRC than symptom criteria. Despite this, CRC still occurs with a negative FIT and the importance of safety netting for patients with severe or persistent symptoms is paramount. We aimed to evaluate the utilization and accuracy of FIT for CRC in low and high-risk symptom groups presenting to primary care, the effectiveness of safety netting in primary care, referral practices with FIT utilization for symptomatic patients and the clinical features of FIT negative patients with CRC. MATERIALS AND METHODS: Medical records and databases of all patients undertaking a FIT sample in the Herts Valleys CCG between June 2019 and November 2021 were reviewed. 13,466 consecutive FIT samples were requested for 12,231 patients between June 2019 and November 2021. RESULTS: Analysis of diagnostic accuracy was undertaken for the first 5341 patients with a minimum of 12 months follow up. Sensitivity for CRC, in FIT ≥ 4 µg Hb/g, ≥ 10 µg Hb/g and ≥ 100 µg Hb/g was 93% (95% CI 85-98%), 91% (95% CI 82-96%) and 72% (95% CI 60-81%) with a number needed to investigate of 36, 19 and 6, respectively. CONCLUSION: A FIT ≥ 10 µg Hb/g in conjunction with ongoing GP clinical concern within 8 weeks had a sensitivity for CRC of 97% (95% CI 90-100%), a PPV of 3.6% (95% CI 3.4-3.7%) and a number needed to investigate to detect one CRC of 28.


Assuntos
Neoplasias Colorretais , Humanos , Sensibilidade e Especificidade , Neoplasias Colorretais/diagnóstico , Colonoscopia , Detecção Precoce de Câncer , Sangue Oculto , Atenção Primária à Saúde , Fezes/química , Hemoglobinas/análise
4.
Emerg Infect Dis ; 28(5)2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35451366

RESUMO

Healthcare-associated invasive group A Streptococcus (iGAS) outbreaks are common worldwide, but only England has reported outbreaks associated with home healthcare (HHC). We describe 10 outbreaks during 2018-2019 in England. A total of 96 iGAS cases (range 2-39 per outbreak) and 28 deaths (case-fatality rate 29%) occurred. Outbreak duration ranged from 3-517 days; median time between sequential cases was 20.5 days (range 1-225 days). Outbreak identification was difficult, but emm typing and whole-genome sequencing improved detection. Network analyses indicated multiple potential transmission routes. Screening of 366 HHC workers from 9 outbreaks identified group A Streptococcus carriage in just 1 worker. Outbreak control required multiple interventions, including improved infection control, equipment decontamination, and antimicrobial prophylaxis for staff. Transmission routes and effective interventions are not yet clear, and iGAS outbreaks likely are underrecognized. To improve patient safety and reduce deaths, public health agencies should be aware of HHC-associated iGAS.


Assuntos
Infecção Hospitalar , Infecções Estreptocócicas , Infecção Hospitalar/epidemiologia , Atenção à Saúde , Surtos de Doenças/prevenção & controle , Inglaterra/epidemiologia , Humanos , Streptococcus pyogenes/genética
5.
Age Ageing ; 50(3): 649-656, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33620453

RESUMO

INTRODUCTION: Previous investigations have identified high rates of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among residents and staff in care homes reporting an outbreak of coronavirus disease 2019 (COVID-19). We investigated care homes reporting a single suspected or confirmed case to assess whether early mass testing might reduce risk of transmission during the peak of the pandemic in London. METHODS: Between 18 and 27 April 2020, residents and staff in care homes reporting a single case of COVID-19 to Public Health England had a nasal swab to test for SARS-CoV-2 infection by reverse transcription polymerase chain reaction and subsequent whole-genome sequencing. Residents and staff in two care homes were re-tested 8 days later. RESULTS: Four care homes were investigated. SARS-CoV-2 positivity was 20% (65/333) overall, ranging between 3 and 59%. Among residents, positivity ranged between 3 and 76% compared with 3 and 40% in staff. Half of the SARS-CoV-2-positive residents (23/46, 50%) and 63% of staff (12/19) reported symptoms within 14 days before or after testing. Repeat testing 8 days later in two care homes with the highest infection rates identified only two new cases. Genomic analysis demonstrated a small number of introduction of the virus into care homes, and distinct clusters within three of the care homes. CONCLUSIONS: We found extensive but variable rates of SARS-CoV-2 infection among residents and staff in care homes reporting a single case of COVID-19. Although routine whole-home testing has now been adopted into practice, care homes must remain vigilant and should be encouraged to report a single suspected case, which should trigger appropriate outbreak control measures.


Assuntos
COVID-19/diagnóstico , Programas de Rastreamento/estatística & dados numéricos , SARS-CoV-2/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , COVID-19/transmissão , Teste de Ácido Nucleico para COVID-19 , Teste para COVID-19 , Inglaterra , Feminino , Humanos , Controle de Infecções , Londres/epidemiologia , Assistência de Longa Duração , Masculino , Pandemias , Políticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/genética , Sequenciamento Completo do Genoma
6.
Euro Surveill ; 26(27)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34240699

RESUMO

We investigated a COVID-19 outbreak of the SARS-CoV-2 Delta variant of concern in a London care home, where 8/21 residents and 14/21 staff had received a single dose of Vaxzevria (ChAdOx1-S; AstraZeneca) vaccine. We identified 24 SARS-CoV-2 infections (16 residents, 8 staff) among 40 individuals (19 residents, 21 staff); four (3 residents, 1 staff) were hospitalised, and none died. The attack rate after one vaccine dose was 35.7% (5/14) for staff and 81.3% (13/16) for residents.


Assuntos
COVID-19 , SARS-CoV-2 , Vacinas contra COVID-19 , Surtos de Doenças , Inglaterra , Humanos , Londres/epidemiologia , Vacinação
7.
Euro Surveill ; 26(8)2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33632376

RESUMO

BackgroundCandida auris is an emerging multidrug-resistant fungal pathogen associated with bloodstream, wound and other infections, especially in critically ill patients. C. auris carriage is persistent and is difficult to eradicate from the hospital environment.AimWe aimed to pilot admission screening for C. auris in intensive care units (ICUs) in England to estimate prevalence in the ICU population and to inform public health guidance.MethodsBetween May 2017 and April 2018, we screened admissions to eight adult ICUs in hospitals with no previous cases of C. auris, in three major cities. Swabs were taken from the nose, throat, axilla, groin, perineum, rectum and catheter urine, then cultured and identified using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Patient records were linked to routine ICU data to describe and compare the demographic and health indicators of the screened cohort with a national cohort of ICU patients admitted between 2016 and 2017.ResultsAll C. auris screens for 921 adults from 998 admissions were negative. The upper confidence limit of the pooled prevalence across all sites was 0.4%. Comparison of the screened cohort with the national cohort showed it was broadly similar to the national cohort with respect to demographics and co-morbidities.ConclusionThese findings imply that C. auris colonisation among patients admitted to ICUs in England is currently rare. We would not currently recommend widespread screening for C. auris in ICUs in England. Hospitals should continue to screen high-risk individuals based on local risk assessment.


Assuntos
Candida , Candidíase , Adulto , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Inglaterra/epidemiologia , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana
8.
Clin Infect Dis ; 71(10): 2553-2560, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31746994

RESUMO

BACKGROUND: Early and accurate treatment of infections due to carbapenem-resistant organisms is facilitated by rapid diagnostics, but rare resistance mechanisms can compromise detection. One year after a Guiana Extended-Spectrum (GES)-5 carbapenemase-positive Klebsiella oxytoca infection was identified by whole-genome sequencing (WGS; later found to be part of a cluster of 3 cases), a cluster of 11 patients with GES-5-positive K. oxytoca was identified over 18 weeks in the same hospital. METHODS: Bacteria were identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry, antimicrobial susceptibility testing followed European Committee on Antimicrobial Susceptibility Testing guidelines. Ertapenem-resistant isolates were referred to Public Health England for characterization using polymerase chain reaction (PCR) detection of GES, pulsed-field gel electrophoresis (PFGE), and WGS for the second cluster. RESULTS: The identification of the first GES-5 K. oxytoca isolate was delayed, being identified by WGS. Implementation of a GES-gene PCR informed the occurrence of the second cluster in real time. In contrast to PFGE, WGS phylogenetic analysis refuted an epidemiological link between the 2 clusters; it also suggested a cascade of patient-to-patient transmission in the later cluster. A novel GES-5-encoding plasmid was present in K. oxytoca, Escherichia coli, and Enterobacter cloacae isolates from unlinked patients within the same hospital group and in human and wastewater isolates from 3 hospitals elsewhere in the United Kingdom. CONCLUSIONS: Genomic sequencing revolutionized the epidemiological understanding of the clusters; it also underlined the risk of covert plasmid propagation in healthcare settings and revealed the national distribution of the resistance-encoding plasmid. Sequencing results also informed and led to the ongoing use of enhanced diagnostic tests for detecting carbapenemases locally and nationally.


Assuntos
Proteínas de Bactérias , beta-Lactamases , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Inglaterra , Humanos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos/genética , Reino Unido , beta-Lactamases/genética
9.
Epidemiol Infect ; 148: e25, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32036802

RESUMO

Chickenpox is caused by varicella-zoster-virus (VZV) and is highly contagious. Immigration detention settings are a high-risk environment for primary VZV transmission, with large, rapidly-changing populations in close quarters, and higher susceptibility among non-UK-born individuals. During outbreaks, operational challenges occur in detention settings because of high-turnover and the potential need to implement population movement restriction for prolonged periods. Between December 2017 and February 2018, four cases of chickenpox were notified amongst 799 detainees in an immigration removal centre (IRC). Microbiological investigations included case confirmation by vesicular fluid polymerase chain reaction, and VZV serology for susceptibility testing. Control measures involved movement restrictions, isolation of cases, quarantining and cohorting of non-immune contacts and extending VZV immunity testing to the wider detainee population to support outbreak management. Immunity was tested for 301/532 (57%) detainees, of whom 24 (8%) were non-immune. The level of non-immunity was lower than expected based on the existing literature on VZV seroprevalence in detained populations in England. Serology results identified non-immune contacts who could be cohorted and, due to the lack of isolation capacity, allowed the placement of cases with immune detainees. The widespread immunity testing of all detainees was proving challenging to sustain because it required significant resources and was having a severe impact on operational capacity and the ability to maintain core business activities at the IRC. Therefore, mathematical modelling was used to assess the impact of scaling back mass immunity testing. Modelling demonstrated that interrupting testing posed a risk of one additional case compared to continuing with testing. As such, the decision was made to stop testing, and the outbreak was successfully controlled without excessive strain on resources. Operational challenges generated learning for future outbreaks, with implications for a local and national policy on IRC staff occupational health requirements, and proposed reception screening of detainees for VZV immunity.


Assuntos
Varicela/epidemiologia , Surtos de Doenças , Transmissão de Doença Infecciosa/prevenção & controle , Emigrantes e Imigrantes , Modelos Teóricos , Testes Sorológicos/métodos , Varicellovirus/imunologia , Adolescente , Adulto , Idoso , Varicela/prevenção & controle , Varicela/transmissão , Inglaterra/epidemiologia , Métodos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Isolamento de Pacientes , Reação em Cadeia da Polimerase , Quarentena , Varicellovirus/isolamento & purificação , Adulto Jovem
10.
Health Care Women Int ; 41(10): 1182-1197, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31084530

RESUMO

In this qualitative study, we investigated knowledge about reproductive tract infections (RTIs) and commercial sex work among female textile workers of Surat, India. We analyzed data from three focus groups conducted with 18 women using content analysis. Participants had some knowledge about the symptoms of RTIs; however, they had limited knowledge about RTI prevention, transmission, and treatment. None used condoms consistently for RTI prevention. The women attributed economic hardship as one of the main reasons for engaging in commercial sex work. Our study is one of the first to evaluate sexual and reproductive health among female textile workers in India.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Infecções do Sistema Genital/epidemiologia , Profissionais do Sexo , Adolescente , Adulto , Preservativos , Estudos Transversais , Feminino , Grupos Focais , Humanos , Índia/epidemiologia , Infecções do Sistema Genital/transmissão , Comportamento Sexual
11.
Clin Infect Dis ; 67(6): 854-860, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-29509833

RESUMO

Background: Invasive Group B streptococcus (GBS) is a major cause of serious neonatal infection. Current strategies to reduce early-onset GBS disease have no impact on late-onset disease (LOD). Although GBS LOD is viewed as a sporadic event in the community, LOD arising within the neonatal intensive care unit (ICU) raises questions about mode of acquisition. Methods: Following a cluster of 4 GBS LOD cases, enhanced surveillance for all GBS LOD was undertaken over 2 years in the neonatal ICU supported by neonatal rectal screening. GBS isolates were serotyped and genome-sequenced. Results: Twelve late -onset invasive GBS episodes were identified (incidence 0.6/1000 live births). Genomic analysis revealed that 11/12 GBS isolates (92%) were linked to at least one other LOD isolate. Isolates from the first cluster were serotype V, resistant to macrolides and lincosamides, and sequencing confirmed isolates were indistinguishable, or distinguishable by only one SNP difference, from each other. Rectal carriage was rare. Prospective surveillance identified three further clusters of LOD due to serotypes Ia (3 cases), Ib (2 cases), and III (2 cases), that would not have been identified without surveillance and genome sequencing, leading to a re-evaluation of interventions required to prevent GBS LOD. Conclusion: Acquisition routes for LOD GBS in the neonatal ICU are poorly understood; cases may not necessarily be sporadic. Within this neonatal ICU, our data suggest that a single case of LOD GBS sepsis should be considered a potential nosocomial transmission event warranting prompt investigation, heightened infection prevention vigilance and action where required.


Assuntos
Unidades de Terapia Intensiva Neonatal , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/epidemiologia , Streptococcus agalactiae/genética , Bacteriemia/epidemiologia , Análise por Conglomerados , Genômica , Humanos , Incidência , Recém-Nascido , Triagem Neonatal , Filogenia , Estudos Prospectivos , Fatores de Risco , Sorogrupo , Streptococcus agalactiae/isolamento & purificação , Reino Unido/epidemiologia , Sequenciamento Completo do Genoma
12.
Biomed Chromatogr ; 31(11)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28370279

RESUMO

A rapid and highly specific assay was developed and validated for the estimation of ZYDPLA1 in rat plasma using liquid chromatography coupled to tandem mass spectrometry with positive electrospray ionization. Method validation comprised of parameters such as specificity, matrix effect, precision, accuracy, recovery, stability, etc. The assay procedure involved a simple protein precipitation of ZYDPLA1 and alprazolam (internal standard) from rat plasma using acetonitrile. Chromatographic separation was achieved with a gradient mobile phase comprising: (A) 0.2% ammonia in purified water; (B) 0.1% formic acid in isopropyl alcohol/methanol (1: 1 v/v); and (C) acetonitrile at a flow rate of 1 mL/min on an ACE-5, C18 (4.6 × 50 mm) column with a run time of 5.5 min. The quantitation of ZYDPLA1 was achieved by the summation of four multiple reaction mode transitions (m/z 399.7 → 383.0, 399.7 → 276.10, 399.7 → 153.20 and 399.7 → 127.20), while that of the internal standard was by a single multiple reaction mode transition (m/z 309.10 → 281.00). The lower limit of quantitation achieved was 0.01 µg/mL and the method showed linearity from 0.01 to 25 µg/mL. The intra- and inter-day precision (%CV) of the quality control samples was within 8.81% and accuracy was ±10% of nominal values. This novel method was applied for evaluation of toxicokinetics of ZYDLA1 in rats.


Assuntos
Cromatografia Líquida/métodos , Inibidores da Dipeptidil Peptidase IV/sangue , Inibidores da Dipeptidil Peptidase IV/toxicidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Inibidores da Dipeptidil Peptidase IV/química , Inibidores da Dipeptidil Peptidase IV/farmacocinética , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
13.
Appl Microbiol Biotechnol ; 100(8): 3533-43, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26621798

RESUMO

Lactose is produced in large amounts as a by-product from the dairy industry. This inexpensive disaccharide can be converted to more useful value-added products such as galacto-oligosaccharides (GOSs) by transgalactosylation reactions with retaining ß-galactosidases (BGALs) being normally used for this purpose. Hydrolysis is always competing with the transglycosylation reaction, and hence, the yields of GOSs can be too low for industrial use. We have reported that a ß-glucosidase from Halothermothrix orenii (HoBGLA) shows promising characteristics for lactose conversion and GOS synthesis. Here, we engineered HoBGLA to investigate the possibility to further improve lactose conversion and GOS production. Five variants that targeted the glycone (-1) and aglycone (+1) subsites (N222F, N294T, F417S, F417Y, and Y296F) were designed and expressed. All variants show significantly impaired catalytic activity with cellobiose and lactose as substrates. Particularly, F417S is hydrolytically crippled with cellobiose as substrate with a 1000-fold decrease in apparent k cat, but to a lesser extent affected when catalyzing hydrolysis of lactose (47-fold lower k cat). This large selective effect on cellobiose hydrolysis is manifested as a change in substrate selectivity from cellobiose to lactose. The least affected variant is F417Y, which retains the capacity to hydrolyze both cellobiose and lactose with the same relative substrate selectivity as the wild type, but with ~10-fold lower turnover numbers. Thin-layer chromatography results show that this effect is accompanied by synthesis of a particular GOS product in higher yields by Y296F and F417S compared with the other variants, whereas the variant F417Y produces a higher yield of total GOSs.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Galactose/metabolismo , Halothiobacillus/enzimologia , Oligossacarídeos/biossíntese , Engenharia de Proteínas , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , Proteínas de Bactérias/química , Halothiobacillus/química , Halothiobacillus/genética , Cinética , Lactose/metabolismo , Especificidade por Substrato , beta-Glucosidase/química
14.
Pharm Dev Technol ; 21(8): 921-932, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26334480

RESUMO

The objective of this study was to develop and evaluate a novel microemulsion based gel formulation containing tazarotene for targeted topical therapy of acne. Psudoternary phase diagrams were constructed to obtain the concentration range of oil, surfactant, and co-surfactant for microemulsion formation. The optimized microemulsion formulation containing 0.05% tazarotene was formulated by spontaneous microemulsification method consisting of 10% Labrafac CC, mixed emulsifiers 15% Labrasol-Cremophor-RH 40 (1:1), 15% Capmul MCM, and 60% distilled water (w/w) as an external phase. All plain and tazarotene-loaded microemulsions were clear and showed physicochemical parameters for desired topical delivery and stability. The permeation profiles of tazarotene through rat skin from optimized microemulsion formulation followed the Higuchi model for controlled permeation. Microemulsion-based gel was prepared by incorporating Carbopol®971P NF in optimized microemulsion formulation having suitable skin permeation rate and skin uptake. Microemulsion-based gel showed desired physicochemical parameters and demonstrated advantage over marketed formulation in improving the skin tolerability of tazarotene indicating its potential in improving its topical delivery. The developed microemulsion-based gel may be a potential drug delivery vehicle for targeted topical delivery of tazarotene in the treatment of acne.


Assuntos
Acne Vulgar/tratamento farmacológico , Emulsões/administração & dosagem , Emulsões/química , Géis/administração & dosagem , Géis/química , Ácidos Nicotínicos/administração & dosagem , Ácidos Nicotínicos/química , Animais , Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Estabilidade de Medicamentos , Excipientes/química , Masculino , Ratos , Ratos Wistar , Pele/efeitos dos fármacos , Absorção Cutânea/efeitos dos fármacos , Tensoativos/química
15.
J Clin Microbiol ; 53(8): 2622-31, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26041902

RESUMO

Whole-genome sequencing (WGS) was carried out on 87 isolates of sequence type 111 (ST-111) of Pseudomonas aeruginosa collected between 2005 and 2014 from 65 patients and 12 environmental isolates from 24 hospital laboratories across the United Kingdom on an Illumina HiSeq instrument. Most isolates (73) carried VIM-2, but others carried IMP-1 or IMP-13 (5) or NDM-1 (1); one isolate had VIM-2 and IMP-18, and 7 carried no metallo-beta-lactamase (MBL) gene. Single nucleotide polymorphism analysis divided the isolates into distinct clusters; the NDM-1 isolate was an outlier, and the IMP isolates and 6/7 MBL-negative isolates clustered separately from the main set of 73 VIM-2 isolates. Within the VIM-2 set, there were at least 3 distinct clusters, including a tightly clustered set of isolates from 3 hospital laboratories consistent with an outbreak from a single introduction that was quickly brought under control and a much broader set dominated by isolates from a long-running outbreak in a London hospital likely seeded from an environmental source, requiring different control measures; isolates from 7 other hospital laboratories in London and southeast England were also included. Bayesian evolutionary analysis indicated that all the isolates shared a common ancestor dating back ∼50 years (1960s), with the main VIM-2 set separating approximately 20 to 30 years ago. Accessory gene profiling revealed blocks of genes associated with particular clusters, with some having high similarity (≥95%) to bacteriophage genes. WGS of widely found international lineages such as ST-111 provides the necessary resolution to inform epidemiological investigations and intervention policies.


Assuntos
Proteínas de Bactérias/genética , Microbiologia Ambiental , Genoma Bacteriano , Genótipo , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Análise de Sequência de DNA , beta-Lactamases/genética , Análise por Conglomerados , Surtos de Doenças , Evolução Molecular , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Reino Unido/epidemiologia
16.
Appl Microbiol Biotechnol ; 99(4): 1731-44, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25173693

RESUMO

Lactose is a major disaccharide by-product from the dairy industries, and production of whey alone amounts to about 200 million tons globally each year. Thus, it is of particular interest to identify improved enzymatic processes for lactose utilization. Microbial ß-glucosidases (BGL) with significant ß-galactosidase (BGAL) activity can be used to convert lactose to glucose (Glc) and galactose (Gal), and most retaining BGLs also synthesize more complex sugars from the monosaccharides by transglycosylation, such as galacto-oligosaccharides (GOS), which are prebiotic compounds that stimulate growth of beneficial gut bacteria. In this work, a BGL from the thermophilic and halophilic bacterium Halothermothrix orenii, HoBGLA, was characterized biochemically and structurally. It is an unspecific ß-glucosidase with mixed activities for different substrates and prominent activity with various galactosidases such as lactose. We show that HoBGLA is an attractive candidate for industrial lactose conversion based on its high activity and stability within a broad pH range (4.5-7.5), with maximal ß-galactosidase activity at pH 6.0. The temperature optimum is in the range of 65-70 °C, and HoBGLA also shows excellent thermostability at this temperature range. The main GOS products from HoBGLA transgalactosylation are ß-D-Galp-(1→6)-D-Lac (6GALA) and ß-D-Galp-(1→3)-D-Lac (3GALA), indicating that D-lactose is a better galactosyl acceptor than either of the monosaccharides. To evaluate ligand binding and guide GOS modeling, crystal structures of HoBGLA were determined in complex with thiocellobiose, 2-deoxy-2-fluoro-D-glucose and glucose. The two major GOS products, 3GALA and 6GALA, were modeled in the substrate-binding cleft of wild-type HoBGLA and shown to be favorably accommodated.


Assuntos
Clostridium/enzimologia , Galactose/metabolismo , Lactose/metabolismo , Oligossacarídeos/biossíntese , beta-Glucosidase/genética , beta-Glucosidase/metabolismo , Clostridium/genética , Cristalografia por Raios X , Estabilidade Enzimática , Glucose/metabolismo , Concentração de Íons de Hidrogênio , Modelos Moleculares , Conformação Proteica , Especificidade por Substrato , Temperatura , beta-Glucosidase/química
17.
J Antimicrob Chemother ; 69(8): 2265-73, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24777901

RESUMO

OBJECTIVES: To evaluate the impact of 'Resident Antimicrobial Management Plan' (RAMP), a novel antimicrobial stewardship tool on systemic antibiotic use for treatment of infection in nursing homes (NHs). METHODS: A pilot cluster randomized control study was conducted in 30 NHs in London. Pre-intervention, we collected point prevalence data on antimicrobial use on three occasions and total antimicrobial consumption for a 12 week period. Post-intervention data were collected in the same manner and included assessment of compliance with RAMP in the intervention group (IG). RESULTS: The number of residents included was 1628 pre-intervention [825 IG/803 control group (CG)] and 1610 post-intervention (838 IG/772 CG). The corresponding pre- and post-intervention point prevalence of systemic antibiotic prescribing for treatment of infection was 6.46% and 6.52% in the IG [estimated prevalence ratio: 1.01 (95% CI: 0.81-1.25), P = 0.94] compared with 5.27% and 5.83%, respectively, in the CG [estimated prevalence ratio: 1.11 (95% CI: 0.87-1.41), P = 0.4]. Total antibiotic consumption was 69.78 defined daily doses/1000 residents/day (DRD) pre-intervention and 66.53 DRD post-intervention in the IG compared with 49.68 and 51.92 DRD, respectively, in the CG. There was a significant decrease of 4.9% (3.25 DRD) in the IG (95% CI: 1.0%-8.6%) (P = 0.02) compared with a significant increase of 5.1% (2.24 DRD) in the CG (95% CI: 0.2%-10.2%) (P = 0.04). Main indications for antibiotics were lower respiratory tract infections (34.1%), urinary tract infections (28.5%) and skin/soft tissue infections (25.1%). CONCLUSIONS: This pilot study demonstrated that use of RAMP was associated with a statistically significant decrease in total antibiotic consumption and has the potential to be an important antimicrobial stewardship tool for NHs.


Assuntos
Antibacterianos/uso terapêutico , Prescrição Inadequada , Casas de Saúde/estatística & dados numéricos , Padrões de Prática Médica , Idoso , Idoso de 80 Anos ou mais , Infecção Hospitalar/tratamento farmacológico , Feminino , Humanos , Assistência de Longa Duração , Masculino , Projetos Piloto , Estudos Prospectivos , Infecções Respiratórias/tratamento farmacológico , Dermatopatias Infecciosas/tratamento farmacológico , Infecções dos Tecidos Moles/tratamento farmacológico , Infecções Urinárias/tratamento farmacológico , beta-Lactamas/uso terapêutico
18.
Biotechnol Rep (Amst) ; 42: e00840, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38645886

RESUMO

Phthalate esters are known to be endocrine disrupting chemicals and are documented to pollute environments. Enzymatic degradation of PAEs is a potential bioremedial strategy to manage contamination. Thermostable bioremedial enzymes have advantages in enzyme manufacturing and storage. In this study, we identified, overexpressed, and characterised a moderately thermostable para-nitrobenzyl esterase from whole genome sequencing of a Bacillus velezensis NP05 from the Great Artesian Basin, capable of sequential 2-step hydrolysis of diisobutyl phthalate. The pnbA enzyme has a molecular weight of 55.14 kDa and pI of 5.31. It preferentially degrades para-nitrophenyl butanoate and has an optimal pH of 7-8. The pnbA esterase has an optimal temperature of 55 °C with a half-life of 4 h. Using HPLC we found that pnbA (0.122 U) can hydrolyse 0.83 mM of DIBP within 25 min. Lastly, pnbA is potentially a more economically viable candidate for enzymatic bioremediation of diisobutyl phthalate as a free enzyme.

19.
Adv Ther ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990433

RESUMO

INTRODUCTION: Some Janus kinase (JAK) inhibitors such as ruxolitinib and fedratinib do not address and may worsen anemia in patients with myelofibrosis. In these cases, the JAK inhibitor may be continued at a reduced dose in an effort to maintain splenic and symptom control, with supportive therapy and/or red blood cell (RBC) transfusions added to manage anemia. This post hoc descriptive analysis of the phase 3 SIMPLIFY-2 trial evaluated the relative benefits of this approach versus switching to the JAK1/JAK2/activin A receptor type 1 inhibitor momelotinib in patients for whom anemia management is a key consideration. METHODS: SIMPLIFY-2 was a randomized (2:1), open-label, phase 3 trial of momelotinib versus best available therapy (BAT; 88.5% continued ruxolitinib) in JAK inhibitor-experienced patients with myelofibrosis (n = 156). Patient subgroups (n = 105 each) were defined by either baseline (1) hemoglobin (Hb) of < 100 g/L or (2) non-transfusion independence (not meeting the criteria of no transfusions and no Hb of < 80 g/L for the previous 12 weeks); outcomes have been summarized descriptively. RESULTS: In both subgroups of interest, week 24 transfusion independence rates were higher with momelotinib versus BAT/ruxolitinib: baseline Hb of < 100 g/L, 22 (33.3%) versus 5 (12.8%); baseline non-transfusion independent, 25 (34.7%) versus 1 (3.0%). Mean Hb levels over time were also generally higher in both subgroups with momelotinib, despite median transfusion rates through week 24 with momelotinib being comparable to or lower than with BAT/ruxolitinib. Spleen and symptom response rates with momelotinib in these subgroups were comparable to the intent-to-treat population, while rates with BAT/ruxolitinib were lower. CONCLUSION: In patients with moderate-to-severe anemia and/or in need of RBC transfusions, outcomes were improved by switching to momelotinib rather than continuing ruxolitinib and using anemia supportive therapies. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02101268.


Patients with the rare blood cancer myelofibrosis often experience symptoms such as tiredness, an increase in the size of their spleens (an organ involved in filtering the blood), and anemia (too few red blood cells). One type of treatment for myelofibrosis, called a Janus kinase (JAK) inhibitor, can help patients to feel better and reduce the size of their spleens, but some JAK inhibitors do not help with anemia and may make it worse. In those situations, patients may continue to take their JAK inhibitor but also receive another type of treatment, called an anemia supportive therapy, and may also receive red blood cell transfusions. This study compared 2 treatment approaches, continuing the JAK inhibitor ruxolitinib and adding an anemia supportive therapy and/or transfusions versus switching to another treatment called momelotinib, in 2 groups of patients from a clinical trial: (1) patients with levels of hemoglobin (a red blood cell protein) at the start of the trial that indicated that they had anemia, and (2) patients who were already receiving red blood cell transfusions at the start of the trial. In both groups, more patients did not need red blood cell transfusions anymore at week 24 with momelotinib, and their hemoglobin levels on average became higher over time. More patients also had improvements in spleen size and symptoms with momelotinib. Overall, outcomes were improved by switching to momelotinib rather than continuing ruxolitinib and using supportive therapies and/or red blood cell transfusions to treat anemia.

20.
J Med Microbiol ; 73(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38771623

RESUMO

The emergent fungal pathogen Candida auris is increasingly recognised as an important cause of healthcare-associated infections globally. It is highly transmissible, adaptable, and persistent, resulting in an organism with significant outbreak potential that risks devastating consequences. Progress in the ability to identify C. auris in clinical specimens is encouraging, but laboratory diagnostic capacity and surveillance systems are lacking in many countries. Intrinsic resistance to commonly used antifungals, combined with the ability to rapidly acquire resistance to therapy, substantially restricts treatment options and novel agents are desperately needed. Despite this, outbreaks can be interrupted, and mortality avoided or minimised, through the application of rigorous infection prevention and control measures with an increasing evidence base. This review provides an update on epidemiology, the impact of the COVID-19 pandemic, risk factors, identification and typing, resistance profiles, treatment, detection of colonisation, and infection prevention and control measures for C. auris. This review has informed a planned 2024 update to the United Kingdom Health Security Agency (UKHSA) guidance on the laboratory investigation, management, and infection prevention and control of Candida auris. A multidisciplinary response is needed to control C. auris transmission in a healthcare setting and should emphasise outbreak preparedness and response, rapid contact tracing and isolation or cohorting of patients and staff, strict hand hygiene and other infection prevention and control measures, dedicated or single-use equipment, appropriate disinfection, and effective communication concerning patient transfers and discharge.


Assuntos
Antifúngicos , COVID-19 , Candida auris , Candidíase , Controle de Infecções , Humanos , Candidíase/prevenção & controle , Candidíase/epidemiologia , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Controle de Infecções/métodos , Candida auris/efeitos dos fármacos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Inglaterra/epidemiologia , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , SARS-CoV-2 , Farmacorresistência Fúngica , Candida/efeitos dos fármacos , Candida/classificação , Candida/isolamento & purificação , Surtos de Doenças/prevenção & controle
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