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1.
Int J Pharm ; 525(1): 249-263, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28450171

RESUMEN

In this study, the influence of key process variables (screw speed, throughput and liquid to solid (L/S) ratio) of a continuous twin screw wet granulation (TSWG) was investigated using a central composite face-centered (CCF) experimental design method. Regression models were developed to predict the process responses (motor torque, granule residence time), granule properties (size distribution, volume average diameter, yield, relative width, flowability) and tablet properties (tensile strength). The effects of the three key process variables were analyzed via contour and interaction plots. The experimental results have demonstrated that all the process responses, granule properties and tablet properties are influenced by changing the screw speed, throughput and L/S ratio. The TSWG process was optimized to produce granules with specific volume average diameter of 150µm and the yield of 95% based on the developed regression models. A design space (DS) was built based on volume average granule diameter between 90 and 200µm and the granule yield larger than 75% with a failure probability analysis using Monte Carlo simulations. Validation experiments successfully validated the robustness and accuracy of the DS generated using the CCF experimental design in optimizing a continuous TSWG process.


Asunto(s)
Composición de Medicamentos/métodos , Comprimidos , Tamaño de la Partícula , Resistencia a la Tracción
2.
Med Vet Entomol ; 29(1): 1-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25087926

RESUMEN

The U.K. has not yet experienced a confirmed outbreak of mosquito-borne virus transmission to people or livestock despite numerous autochthonous epizootic and human outbreaks of mosquito-borne diseases on the European mainland. Indeed, whether or not British mosquitoes are competent to transmit arboviruses has not been established. Therefore, the competence of a local (temperate) British mosquito species, Ochlerotatus detritus (=Aedes detritus) (Diptera: Culicidae) for transmission of a member of the genus Flavivirus, Japanese encephalitis virus (JEV) as a model for mosquito-borne virus transmission was assessed. The JEV competence in a laboratory strain of Culex quinquefasciatus (Diptera: Culicidae), a previously incriminated JEV vector, was also evaluated as a positive control. Ochlerotatus detritus adults were reared from field-collected juvenile stages. In oral infection bioassays, adult females developed disseminated infections and were able to transmit virus as determined by the isolation of virus in saliva secretions. When pooled at 7-21 days post-infection, 13% and 25% of O. detritus were able to transmit JEV when held at 23 °C and 28 °C, respectively. Similar results were obtained for C. quinquefasciatus. To our knowledge, this study is the first to demonstrate that a British mosquito species, O. detritus, is a potential vector of an exotic flavivirus.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie)/fisiología , Encefalitis Japonesa/transmisión , Insectos Vectores/virología , Ochlerotatus/virología , Aedes/fisiología , Aedes/virología , Animales , Encefalitis Japonesa/virología , Inglaterra , Femenino , Calor , Humanos , Insectos Vectores/fisiología , Ochlerotatus/fisiología
3.
Water Res ; 56: 122-32, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-24662095

RESUMEN

Nutrient stewardship is emerging as an issue of global importance, which will drive the development of nutrient recovery in the near to medium future. This will impact wastewater treatment practices, environmental protection, sustainable agriculture and global food security. A modelling framework for precipitation-based nutrient recovery systems has been developed, incorporating non-ideal solution thermodynamics, a dynamic mass balance and a dynamic population balance to track the development of the precipitating particles. The mechanisms of crystal nucleation and growth and, importantly, aggregation are considered. A novel approach to the population balance embeds the nucleation rate into the model, enabling direct regression of its kinetic parameters. The case study chosen for the modelling framework is that of struvite precipitation, given its wide interest and commercial promise as one possible nutrient recovery pathway. Power law kinetic parameters for nucleation, crystal growth and particle aggregation rates were regressed from an ensemble data set generated from 14 laboratory seeded batch experiments using synthetic solutions. These experiments were highly repeatable, giving confidence to the regressed parameter values. The model successfully describes the dynamic responses of solution pH, the evolving particle size distribution subject to nucleation, growth and aggregation effects and the aqueous magnesium concentration in the liquid phase. The proposed modelling framework could well be extended to other, more complex systems, leading to an improved understanding and commensurately greater confidence in the design, operation and optimisation of large-scale nutrient recovery processes from complex effluents.


Asunto(s)
Compuestos de Magnesio/química , Modelos Químicos , Fosfatos/química , Fósforo/química , Contaminantes Químicos del Agua/química , Cinética , Estruvita
4.
Br J Dermatol ; 170(4): 895-900, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24341905

RESUMEN

BACKGROUND: Morphoea is a rare fibrosing disease of the skin and subcutaneous tissue with an unpredictable disease course, running the spectrum from mild skin involvement to severe disfigurement or extracutaneous complications. OBJECTIVES: Our objective was to describe the natural history of paediatric morphoea and determine patient variables that were associated with severe disease. PATIENTS AND METHODS: We conducted a retrospective chart review of patients with morphoea seen in one paediatric hospital system. Information about demographics, clinical characteristics, disease course and treatment were collected. Statistical analysis was performed using appropriate univariate tests and a multivariable model. RESULTS: One hundred and fourteen patients met study inclusion criteria. The female : male ratio was 2·6 : 1, and the median age of onset was 7 years old. There were 55 patients (48%) with linear morphoea, 38 patients (33%) with circumscribed morphoea, 12 patients (11%) with generalized morphoea, and nine patients (8%) with mixed morphoea. Neurological symptoms and joint involvement were present in 27 subjects (24%). Extracutaneous manifestations occurred in 38% of subjects with linear morphoea, compared with 15% with generalized morphoea and 3% with circumscribed morphoea (P = 0·0001). Thirty-six per cent of children with disease onset prior to 10 years of age and 5% of children with disease onset after 10 years of age had extracutaneous manifestations (P = 0·0002). Both linear morphoea and early-onset disease were significantly associated with extracutaneous involvement in a multivariable model. CONCLUSIONS: Children with linear morphoea and disease onset before 10 years of age should be monitored closely for extracutaneous manifestations and need early treatment with systemic medications to prevent disease complications.


Asunto(s)
Esclerodermia Localizada/epidemiología , Administración Cutánea , Adolescente , Edad de Inicio , Niño , Fármacos Dermatológicos/administración & dosificación , Quimioterapia Combinada , Femenino , Humanos , Infusiones Intravenosas , Masculino , Estudios Retrospectivos , Factores de Riesgo , Esclerodermia Localizada/complicaciones , Esclerodermia Localizada/tratamiento farmacológico , Wisconsin/epidemiología
5.
Br J Dermatol ; 169(2): 428-33, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23601021

RESUMEN

BACKGROUND: Paediatric cutaneous lupus erythematosus (CLE) is uncommon and inadequately described in the literature. Similar to adults, children with CLE develop LE-specific and/or LE-nonspecific skin findings. Similarities and differences in demographics and clinical course between paediatric and adult CLE have not been sufficiently described. OBJECTIVES: To detail the demographic and clinical features of paediatric CLE and compare these findings with those reported in the adult literature. METHODS: A retrospective chart review was performed of 53 children seen in a paediatric dermatology clinic with cutaneous manifestations of LE. RESULTS: Patients presented with all five major subtypes of CLE, with some notable differences from adult CLE and previously published reports of paediatric CLE. Progression from discoid LE to systemic LE (SLE) did not occur in our cohort. Patients with subacute CLE were more likely than adults to have lesions below the waist as well as concomitant SLE. Sex distribution for CLE in our study was equal prior to puberty and female predominant in post-pubertal patients. CONCLUSIONS: Children with CLE have variable clinical presentations and progression to SLE that may be different from adult disease. Specifically, children with acute and subacute CLE may be more likely than adults to have systemic disease; therefore, patients with these subtypes should be monitored closely for evidence of SLE. Study limitations included small patient numbers that may limit the ability to generalize these data and relatively short follow-up intervals.


Asunto(s)
Lupus Eritematoso Cutáneo/epidemiología , Enfermedad Aguda , Adolescente , Edad de Inicio , Niño , Preescolar , Enfermedad Crónica , Femenino , Humanos , Lactante , Recién Nacido , Lupus Eritematoso Cutáneo/etnología , Lupus Eritematoso Cutáneo/patología , Masculino , Estudios Retrospectivos , Distribución por Sexo , Wisconsin/epidemiología
6.
J Viral Hepat ; 20(4): e96-106, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23490396

RESUMEN

Some hepatitis C (HCV)-uninfected, high-risk individuals have HCV-specific cellular immunity without viraemia or seroconversion. The characteristics of these responses and the risk behavioural associations were studied in 94 subjects in a prospective cohort of recently seronegative prisoners reporting injecting drug use (IDU). Detailed behavioural data were collected. HCV antibody and PCR testing were performed. ELISpot assays for HCV-induced interferon (IFN)-γ and interleukin (IL)-2 production by T lymphocytes, as well as multiplex in vitro cytokine production assays, were performed. Seventy-eight subjects remained antibody and PCR negative and 16 seroconverted. Of the seronegative group, 22 (28%) had IFN-γ ELISpot responses in comparison with 13 of the 16 seroconverters (82%). This seronegative immune status was associated positively with injecting anabolic steroids and negatively with a recent break from IDU. The IFN-γ ELISpot responses involved both CD4 and CD8 T lymphocytes and were comparable in magnitude, but narrower in specificity, in uninfected subjects than in seroconverters. A subset of seronegative subjects had HCV-induced cytokine production patterns comparable with the seroconverters with increased production of IFN-γ, IL-2 and tumour necrosis factor (TNF)-α and reduced IL-10 in response to nonstructural peptides. In conclusion, comparable patterns of HCV-specific cellular immunity are found in recently infected subjects and in a minority of high-risk, uninfected subjects. Further characterization of these responses and their protective efficacy will inform HCV vaccine development.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Exposición a Riesgos Ambientales , Hepacivirus/inmunología , Prisioneros , Adulto , Citocinas/metabolismo , Ensayo de Immunospot Ligado a Enzimas , Femenino , Humanos , Masculino , Adulto Joven
7.
Euro Surveill ; 18(1): 4-7, 2013 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-23305714

RESUMEN

Following a suspected case of hantavirus in a patientsuffering from acute kidney injury, rodents fromthe patient's property in Yorkshire and the Humber,United Kingdom (UK) were screened for hantaviruses.Hantavirus RNA was detected via RT-PCR in two Rattusnorvegicus. Complete sequencing and phylogeneticanalysis established the virus as a Seoul hantavirus,which we have provisionally designated as strainHumber. This is the first hantavirus isolated from wildrodents in the UK and confirms the presence of a pathogenicSeoul virus in Europe.


Asunto(s)
Lesión Renal Aguda/diagnóstico , Anticuerpos Antivirales/sangre , Infecciones por Hantavirus/epidemiología , ARN Viral/análisis , Virus Seoul/aislamiento & purificación , Lesión Renal Aguda/virología , Animales , Enfermedades Transmisibles Emergentes/virología , Reservorios de Enfermedades , Infecciones por Hantavirus/diagnóstico , Infecciones por Hantavirus/virología , Humanos , Masculino , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Enfermedades de los Roedores , Virus Seoul/genética , Análisis de Secuencia de ADN , Reino Unido/epidemiología
8.
Infection ; 41(1): 27-31, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22798048

RESUMEN

PURPOSE: We looked for herpes simplex virus types 1 and 2 (HSV-1 and HSV-2, respectively), varicella zoster virus (VZV), Epstein-Barr virus (EBV) and cytomegalovirus (CMV) DNA in Malawian adults with clinically suspected meningitis. METHODS: We collected cerebrospinal fluid (CSF) from consecutive adults admitted with clinically suspected meningitis to Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi, for a period of 3 months. Those with proven bacterial or fungal meningitis were excluded. Real-time polymerase chain reaction (PCR) was performed on the CSF for HSV-1 and HSV-2, VZV, EBV and CMV DNA. RESULTS: A total of 183 patients presented with clinically suspected meningitis. Of these, 59 (32 %) had proven meningitis (bacterial, tuberculous or cryptococcal), 39 (21 %) had normal CSF and 14 (8 %) had aseptic meningitis. For the latter group, a herpes virus was detected in 9 (64 %): 7 (50 %) had EBV and 2 (14 %) had CMV, all were human immunodeficiency virus (HIV)-positive. HSV-2 and VZV were not detected. Amongst those with a normal CSF, 8 (21 %) had a detectable herpes virus, of which 7 (88 %) were HIV-positive. CONCLUSIONS: The spectrum of causes of herpes viral meningitis in this African population is different to that in Western industrialised settings, with EBV being frequently detected in the CSF. The significance of this needs further investigation.


Asunto(s)
Infecciones por Herpesviridae/virología , Herpesviridae/aislamiento & purificación , Meningitis Viral/virología , Adulto , Citomegalovirus/aislamiento & purificación , ADN Viral/líquido cefalorraquídeo , Femenino , Herpesviridae/genética , Infecciones por Herpesviridae/diagnóstico , Infecciones por Herpesviridae/epidemiología , Herpesvirus Humano 1/aislamiento & purificación , Herpesvirus Humano 2/aislamiento & purificación , Herpesvirus Humano 3/aislamiento & purificación , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Malaui/epidemiología , Masculino , Meningitis Viral/diagnóstico , Meningitis Viral/epidemiología
9.
Br J Cancer ; 105(1): 44-52, 2011 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-21629245

RESUMEN

BACKGROUND: The objectives of this phase I study were to determine the safety, pharmacokinetics (PK), pharmacodynamics and efficacy of brivanib combined with full-dose cetuximab in patients with advanced gastrointestinal malignancies. METHODS: Patients with advanced gastrointestinal malignancies who had failed prior therapies received brivanib (320, 600 or 800 mg daily) plus cetuximab (400 mg m(-2) loading dose then 250 mg m(-2) weekly). Assessments included adverse events, PK, tumour response, 2[18F]fluoro-2-deoxyglucose positron-emitting tomography and K-Ras mutation analyses. RESULTS: Toxicities observed were manageable; the most common treatment-related toxicities (>10% of patients) were fatigue, diarrhoea, anorexia, increase in aspartate aminotransferase and alanine aminotransferase, acneiform dermatitis, headache, mucosal inflammation, nausea, dry skin, vomiting, hypertension, pruritus, proteinuria and weight loss. Of 62 patients, 6 (9.7%) had objective radiographic partial responses, with an overall response rate of 10%. Median duration of response was 9.2 months; median progression-free survival was 3.9 months. CONCLUSIONS: The acceptable toxicity profile and efficacy of brivanib observed in this study were promising. These findings are being further evaluated in a phase III study of brivanib plus cetuximab vs cetuximab alone in patients previously treated with combination chemotherapy for K-Ras wild-type advanced metastatic colorectal cancer.


Asunto(s)
Alanina/análogos & derivados , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/uso terapéutico , Neoplasias Gastrointestinales/tratamiento farmacológico , Terapia Recuperativa , Triazinas/farmacocinética , Triazinas/uso terapéutico , Adulto , Anciano , Alanina/farmacocinética , Alanina/uso terapéutico , Anticuerpos Monoclonales Humanizados , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Cetuximab , Quimioterapia Combinada , Femenino , Neoplasias Gastrointestinales/patología , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Tasa de Supervivencia , Distribución Tisular , Resultado del Tratamiento , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores
10.
Ann Oncol ; 22(6): 1413-1419, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21131369

RESUMEN

BACKGROUND: This study was designed to determine the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of brivanib in patients with advanced/metastatic solid tumors. PATIENTS AND METHODS: Ninety patients enrolled in this two-part, phase I open-label study of oral brivanib alaninate. The primary objectives of this study were (in part A) dose-limiting toxicity, maximum tolerated dose (MTD) and the lowest biologically active dose level and (in part B) the optimal dose/dose range. The secondary objectives of this study were preliminary evidence of antitumor activity, PK and PD. RESULTS: Across part A (open-label dose escalation and MTD) and part B (open-label dose optimization), 68 patients received brivanib alaninate. Brivanib demonstrated a manageable toxicity profile at doses of 180-800 mg. Most toxic effects were mild. Systemic exposure of the active moiety brivanib increased linearly ≤1000 mg/day. The MTD was 800 mg/day. Forty-four patients were treated at the MTD: 20 with 800 mg continuously, 11 with 800 mg intermittently and 13 with 400 mg b.i.d. doses. Partial responses were confirmed in two patients receiving brivanib ≥600 mg. Dynamic contrast-enhanced magnetic resonance imaging demonstrated statistically significant decreases in parameters reflecting tumor vascularity and permeability after multiple doses in the 800-mg continuous q.d. and 400-mg b.i.d. dose cohorts. CONCLUSION: In patients with advanced/metastatic cancer, brivanib demonstrates promising antiangiogenic and antitumor activity and manageable toxicity at doses ≤800 mg orally q.d., the recommended phase II study dose.


Asunto(s)
Alanina/análogos & derivados , Inhibidores de la Angiogénesis/farmacología , Antineoplásicos/farmacología , Neoplasias/tratamiento farmacológico , Receptores de Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Triazinas/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Alanina/farmacología , Alanina/uso terapéutico , Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/uso terapéutico , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Metástasis de la Neoplasia , Neoplasias/irrigación sanguínea , Neoplasias/mortalidad , Neovascularización Patológica , Triazinas/uso terapéutico
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