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1.
Reprod Toxicol ; 113: 35-41, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35944741

RESUMO

Bone has recently emerged as a target organ for some Janus kinase (JAK) inhibitors in adult and/or juvenile animal toxicity studies. Oral administration of tofacitinib, a JAK inhibitor, was not associated with clinical or macroscopic effects on bone growth and development in a rat juvenile animal study (JAS) with tofacitinib dosing starting on postnatal day (PND) 21. However, given that previous JAS did not include a targeted evaluation of bone, inclusive of microscopic examination, an additional rat JAS was conducted to further assess this risk. In this subsequent JAS, administration of tofacitinib from PND 7-49 or from PND 21-49 did not result in any direct effects on bone, with no histologic effects on developing bone. The only bone effect in this JAS was nonadverse shorter femur length, which was not considered to be a direct effect of tofacitinib, but rather an indicator of growth delay, as this was associated with lower body weights. There were no effects on femur length or body weight after a 2-month recovery period. To further explore the relationship between body weight and femur length, historical control data were analyzed from control rats in other JAS. This analysis clearly demonstrated that shorter femur length can occur as an indirect effect that is highly associated with lower body weight, consistent with what was observed in the JAS with tofacitinib. These analyses provide a robust and valuable data set to support the interpretation of such data in JAS, and further support the lack of direct effects of tofacitinib on bone growth and development. As with the previously conducted juvenile studies with tofacitinib, the additional JAS did not identify any special JAS-based concerns for use in pediatric patients as young as 2 years of age.


Assuntos
Inibidores de Janus Quinases , Animais , Peso Corporal , Fêmur , Inibidores de Janus Quinases/toxicidade , Janus Quinases , Piperidinas/toxicidade , Pirimidinas/toxicidade , Ratos
2.
Reprod Toxicol ; 108: 56-61, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35101563

RESUMO

Nirmatrelvir (PF-07321332; NMV) the antiviral component of PAXLOVID™ is a potent and selective inhibitor of the SARS-CoV-2 main protease (Mpro), which plays a critical role in viral replication. PAXLOVID, comprised of nirmatrelvir and ritonavir (used as a pharmacokinetic enhancer), is an oral therapy currently in development as a therapeutic option for those infected with SARS-CoV-2 to prevent progression to severe disease, hospitalization, and death. PAXLOVID has been shown to be efficacious against hospitalization and death in two Phase 2/3 clinical studies that evaluated non hospitalized patients both with and without high risk factors for progression to severe illness. Given that males and females of reproductive age are included in the intended patient population, we assessed the potential effects of NMV up to the limit dose of 1000 mg/kg/day in ICH guideline embryo-fetal development studies in rats and rabbits, and a fertility and early embryonic development study in rats. There were no effects on male and female fertility or early embryonic development in rats, and no severe manifestations of developmental toxicity in rats or rabbits. The lack of adverse findings reported here in nonclinical species is consistent with the intended therapeutic target of NMV (a virus specific protein not present in mammalian cells), the favorable off-target selectivity profile, and lack of genetic toxicity. The results of these nonclinical studies with NMV along with existing ritonavir safety information indicate that there are no clinically relevant risks associated with PAXLOVID administration during pregnancy and in males and females of reproductive age.


Assuntos
Antivirais/toxicidade , Tratamento Farmacológico da COVID-19 , Desenvolvimento Embrionário/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Lactamas/toxicidade , Leucina/toxicidade , Nitrilas/toxicidade , Prolina/toxicidade , Ritonavir/toxicidade , Animais , Combinação de Medicamentos , Feminino , Infertilidade/induzido quimicamente , Masculino , Gravidez , Coelhos , Ratos , Ratos Wistar
3.
Sci Rep ; 10(1): 9663, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541782

RESUMO

Additive manufacturing currently facilitates new avenues for materials discovery that have not been fully explored. In this study we reveal how additive manufacturing can be leveraged to produce dispersion strengthened (DS), multi-principal element alloys (MPEA) without the use of traditional mechanical alloying or chemical reactions. This new processing technique employed resonant acoustic mixing to coat an equiatomic NiCoCr powder with nano-scale yttrium oxides. Then, through laser powder bed fusion (L-PBF), the coated powder was successfully consolidated into 99.9% dense parts. Microstructural analysis confirmed the successful incorporation and dispersion of nano-scale oxides throughout the build volume. Furthermore, high temperature mechanical testing of the DS alloys showed significant improvements in strength and ductility over the baseline NiCoCr. As a result, this recently discovered processing route opens a new alloy design and production path that is synergistic between additive manufacturing and dispersion strengthening, possibly enabling a new generation of high-performance alloys.

4.
Nucleic Acids Res ; 48(12): 6740-6758, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32463444

RESUMO

How genetic defects trigger the molecular changes that cause late-onset disease is important for understanding disease progression and therapeutic development. Fuchs' endothelial corneal dystrophy (FECD) is an RNA-mediated disease caused by a trinucleotide CTG expansion in an intron within the TCF4 gene. The mutant intronic CUG RNA is present at one-two copies per cell, posing a challenge to understand how a rare RNA can cause disease. Late-onset FECD is a uniquely advantageous model for studying how RNA triggers disease because: (i) Affected tissue is routinely removed during surgery; (ii) The expanded CTG mutation is one of the most prevalent disease-causing mutations, making it possible to obtain pre-symptomatic tissue from eye bank donors to probe how gene expression changes precede disease; and (iii) The affected tissue is a homogeneous single cell monolayer, facilitating accurate transcriptome analysis. Here, we use RNA sequencing (RNAseq) to compare tissue from individuals who are pre-symptomatic (Pre_S) to tissue from patients with late stage FECD (FECD_REP). The abundance of mutant repeat intronic RNA in Pre_S and FECD_REP tissue is elevated due to increased half-life in a corneal cells. In Pre_S tissue, changes in splicing and extracellular matrix gene expression foreshadow the changes observed in advanced disease and predict the activation of the fibrosis pathway and immune system seen in late-stage patients. The absolute magnitude of splicing changes is similar in pre-symptomatic and late stage tissue. Our data identify gene candidates for early drivers of disease and biomarkers that may represent diagnostic and therapeutic targets for FECD. We conclude that changes in alternative splicing and gene expression are observable decades prior to the diagnosis of late-onset trinucleotide repeat disease.


Assuntos
Distrofia Endotelial de Fuchs/genética , Fator de Transcrição 4/genética , Expansão das Repetições de Trinucleotídeos/genética , Repetições de Trinucleotídeos/genética , Adulto , Idoso , Biomarcadores/metabolismo , Córnea/metabolismo , Córnea/patologia , Feminino , Distrofia Endotelial de Fuchs/patologia , Distrofia Endotelial de Fuchs/terapia , Regulação da Expressão Gênica/genética , Predisposição Genética para Doença , Humanos , Íntrons/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Especificidade de Órgãos/genética , Análise de Sequência de RNA
5.
Br J Surg ; 107(1): 103-112, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869460

RESUMO

BACKGROUND: Postoperative complications after resection of oesophagogastric carcinoma can result in considerable early morbidity and mortality. However, the long-term effects on survival are less clear. METHODS: All patients undergoing intentionally curative resection for oesophageal or gastric cancer between 2006 and 2016 were selected from an institutional database. Patients were categorized by complication severity according to the Clavien-Dindo classification (grades 0-V). Complications were defined according to an international consensus statement. The effect of leak and severe non-leak-related complications on overall survival, recurrence and disease-free survival was assessed using Kaplan-Meier analyses to evaluate differences between groups. All factors significantly associated with survival in univariable analysis were entered into a Cox multivariable regression model with stepwise elimination. RESULTS: Some 1100 patients were included, with a median age of 69 (range 28-92) years; 48·1 per cent had stage III disease and cancer recurred in 428 patients (38·9 per cent). Complications of grade III or higher occurred in 244 patients (22·2 per cent). The most common complications were pulmonary (29·9 per cent), with a 13·0 per cent incidence of pneumonia. Rates of atrial dysrhythmia and anastomotic leak were 10·0 and 9·6 per cent respectively. Patients with a grade III-IV leak did not have significantly reduced overall survival compared with those who had grade 0-I complications. However, patients with grade III-IV non-leak-related complications had reduced median overall survival (19·7 versus 42·7 months; P < 0·001) and disease-free survival (18·4 versus 36·4 months; P < 0·001). Cox regression analysis identified age, tumour stage, resection margin and grade III-IV non-leak-related complications as independent predictors of poor overall and disease-free survival. CONCLUSION: Beyond the acute postoperative period, anastomotic leak does not adversely affect survival, however, other severe postoperative complications do reduce long-term overall and disease-free survival.


Assuntos
Neoplasias Esofágicas/cirurgia , Recidiva Local de Neoplasia/mortalidade , Complicações Pós-Operatórias/mortalidade , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Anastomótica/mortalidade , Intervalo Livre de Doença , Inglaterra/epidemiologia , Neoplasias Esofágicas/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade
6.
Reprod Toxicol ; 88: 76-84, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31362042

RESUMO

Palbociclib is a selective inhibitor of the cyclin-dependent kinase (CDK) 4/6, approved for the treatment of breast cancer. We assessed the potential effects of oral administration of palbociclib on reproduction and development. There were no effects on female or male fertility indices; however, in the male there was seminiferous tubule degeneration in the testes and secondary findings in the epididymides, lower testicular and epididymal weights, sperm density and motility. Palbociclib was not teratogenic in rats or rabbits; however, in the presence of maternal toxicity (lower maternal body weight gain and food consumption), low fetal body weights were observed in rats and small forepaw phalanges were noted in rabbits. There were, however, no adverse effects on the F1 generation in a pre- and post-natal developmental toxicity study in the rat.


Assuntos
Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Piperazinas/toxicidade , Piridinas/toxicidade , Animais , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Fertilidade/efeitos dos fármacos , Desenvolvimento Fetal/efeitos dos fármacos , Masculino , Coelhos , Ratos , Ratos Sprague-Dawley
7.
Rev Sci Instrum ; 90(4): 043504, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31043003

RESUMO

Ray-tracing techniques are applied to filtered divertor imaging, a diagnostic that has long suffered from artifacts due to the polluting effect of reflected light in metal walled fusion machines. Physically realistic surface reflections were modeled using a Cook-Torrance micro-facet bi-directional reflection distribution function applied to a high resolution mesh of the vessel geometry. In the absence of gonioreflectometer measurements, a technique was developed to fit the free parameters of the Cook-Torrance model against images of the JET in-vessel light sources. By coupling this model with high fidelity plasma fluid simulations, photo-realistic renderings of a number of tokamak plasma emission scenarios were generated. Finally, a sensitivity matrix describing the optical coupling of a JET divertor camera and the emission profile of the plasma was obtained, including full reflection effects. These matrices are used to perform inversions on measured data and shown to reduce the level of artifacts in inverted emission profiles.

8.
Eur J Pharm Sci ; 123: 502-514, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30098391

RESUMO

As explained by the free drug theory, the unbound fraction of drug has long been thought to drive the efficacy of a molecule. Thus, the fraction unbound term, or fu, appears in equations for fundamental pharmacokinetic parameters such as clearance, and is used when attempting in vitro to in vivo extrapolation (IVIVE). In recent years though, it has been noted that IVIVE does not always yield accurate predictions, and that some highly protein bound ligands have more efficient uptake than can be explained by their unbound fractions. This review explores the evolution of fu terms included when implementing IVIVE, the concept of protein-facilitated uptake, and the mechanisms that have been proposed to account for facilitated uptake.


Assuntos
Proteínas Sanguíneas/metabolismo , Modelos Biológicos , Preparações Farmacêuticas/metabolismo , Farmacocinética , Animais , Transporte Biológico , Humanos , Ligantes , Proteínas de Membrana Transportadoras/metabolismo , Preparações Farmacêuticas/administração & dosagem , Ligação Proteica
9.
J Dent Res ; 97(5): 530-536, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29439642

RESUMO

Step-growth thiol-Michael photopolymerizable resins, constituting an alternative chemistry to the current methacrylate-based chain-growth polymerizations, were developed and evaluated for use as dental restorative materials. The beneficial features inherent to anion-mediated thiol-Michael polymerizations were explored, such as rapid photocuring, low stress generation, ester content tunability, and improved mechanical performance in a moist environment. An ester-free tetrafunctional thiol and a ultraviolet-sensitive photobase generator were implemented to facilitate thiol-Michael photopolymerization. Thiol-Michael resins of varied ester content were fabricated under suitable light activation. Polymerization kinetics and shrinkage stress were determined with Fourier-transform infrared spectroscopy coupled with tensometery measurements. Thermomechanical properties of new materials were evaluated by dynamic mechanical analysis and in 3-point bending stress-strain experiments. Photopolymerization kinetics, polymerization shrinkage stress, glass transition temperature, flexural modulus, flexural toughness, and water sorption/solubility were compared between different thiol-Michael systems and the BisGMA/TEGDMA control. Furthermore, the mechanical performance of 2 thiol-Michael composites and a control composite were compared before and after extensive conditioning in water. All photobase-catalyzed thiol-Michael polymerization matrices achieved >90% conversion with a dramatic reduction in shrinkage stress as compared with the unfilled dimethacrylate control. One prototype of ester-free thiol-Michael formulations had significantly better water uptake properties than the BisGMA/TEGDMA control system. Although exhibiting relatively lower Young's modulus and glass transition temperatures, highly uniform thiol-Michael materials achieved much higher toughness than the BisGMA/TEGDMA control. Moreover, low-ester thiol-Michael composite systems show stable mechanical performance even after extensive water treatment. Although further resin/curing methodology optimization is required, the photopolymerized thiol-Michael prototype resins can now be recognized as promising candidates for implementation in composite dental restorative materials.


Assuntos
Materiais Dentários/uso terapêutico , Resinas Sintéticas/uso terapêutico , Resinas Compostas/uso terapêutico , Restauração Dentária Permanente/métodos , Análise de Fourier , Humanos , Polimerização , Polímeros/uso terapêutico , Ácidos Polimetacrílicos/uso terapêutico , Compostos de Sulfidrila/uso terapêutico
10.
Ann R Coll Surg Engl ; 99(5): 378-384, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28462649

RESUMO

The optimal management of resectable oesophageal adenocarcinoma is controversial, with many centres using neoadjuvant chemotherapy following the Medical Research Council (MRC) oesophageal working group (OE02) trial and the MRC Adjuvant Gastric Infusional Chemotherapy (MAGIC) trial. The more intensive MAGIC regimen is used primarily in gastric cancer but some also use it for oesophageal cancer. A database of cancer resections (2001-2013) provided information on survival of patients following either OE02 or MAGIC-type treatment. The data were compared using Kaplan-Meier analysis. Straight-to-surgery patients were also reviewed and divided into an 'early' cohort (2001-2006, OE02 era) and a 'late' cohort (2006-2013, MAGIC era) to estimate changes in survival over time. Subgroup analysis was performed for responders (tumour regression grade [TRG] 1-3) versus non-responders (TRG 4 and 5) and for anatomical site (gastro-oesophageal junction [GOJ] vs oesophagus). An OE02 regimen was used for 97 patients and 275 received a MAGIC regimen. Those in the MAGIC group were of a similar age to those undergoing OE02 chemotherapy but the proportion of oesophageal cancers was higher among MAGIC patients than among those receiving OE02 treatment. MAGIC patients had a significantly lower stage following chemotherapy than OE02 patients and a higher median overall survival although TRG was similar. On subgroup analysis, this survival benefit was maintained for GOJ and oesophageal cancer patients as well as non-responders. Analysis of responders showed no difference between regimens. 'Late' group straight-to-surgery patients were significantly older than those in the 'early' group. Survival, however, was not significantly different for these two cohorts. Although the original MAGIC trial comprised few oesophageal cancer cases, our patients had better survival with MAGIC than with OE02 chemotherapy in all anatomical subgroups, even though there was no significant change in operative survival over the time period in which these patients were treated. The use of the MAGIC regimen should therefore be encouraged in cases of operable oesophagogastric adenocarcinoma.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/mortalidade , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/mortalidade , Terapia Neoadjuvante/mortalidade , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Estudos de Coortes , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/cirurgia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores
11.
Public Health ; 136: 57-65, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26993202

RESUMO

OBJECTIVES: Most quality appraisal tools were developed for clinical medicine and tend to be study-specific with a strong emphasis on risk of bias. In order to be more relevant to public health, an appropriate quality appraisal tool needs to be less reliant on the evidence hierarchy and consider practice applicability. Given the broad range of study designs used in public health, the objective of this study was to develop and validate a meta-tool that combines public health-focused principles of appraisal coupled with a set of design-specific companion tools. STUDY DESIGN: Several design methods were used to develop and validate the tool including literature review, synthesis, and validation with a reference standard. METHODS: A search of critical appraisal tools relevant to public health was conducted; core concepts were collated. The resulting framework was piloted during three feedback sessions with public health practitioners. Following subsequent revisions, the final meta-tool, the Meta Quality Appraisal Tool (MetaQAT), was then validated through a content analysis of appraisals conducted by two groups of experienced public health researchers (MetaQAT vs generic appraisal form). RESULTS: The MetaQAT framework consists of four domains: relevancy, reliability, validity, and applicability. In addition, a companion tool was assembled from existing critical appraisal tools to provide study design-specific guidance on validity appraisal. Content analysis showed similar methodological and generalizability concerns were raised by both groups; however, the MetaQAT appraisers commented more extensively on applicability to public health practice. CONCLUSIONS: Critical appraisal tools designed for clinical medicine have limitations for use in the context of public health. The meta-tool structure of the MetaQAT allows for rigorous appraisal, while allowing users to simultaneously appraise the multitude of study designs relevant to public health research and assess non-standard domains, such as applicability.


Assuntos
Metanálise como Assunto , Saúde Pública , Projetos de Pesquisa/normas , Humanos , Projetos Piloto , Reprodutibilidade dos Testes
12.
Org Biomol Chem ; 14(24): 5555-8, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-26924258

RESUMO

As more methodologies for generating and manipulating biomimetic cellular systems are developed, opportunities arise for combining different methods to create more complex synthetic biological constructs. This necessitates an increasing need for tools to selectively trigger individual methodologies. Here we demonstrate ruthenium tris-bipyridine mediated photoredox triggering of the copper catalyzed alkyne azide cycloaddition reaction (CuAAC), resulting in the synthesis of biomimetic phospholipids in situ, and subsequent membrane assembly. The use of a ruthenium-copper electron transport chain to trigger phospholipid assembly opens up future opportunities for spatiotemporal synthesis of membranes.


Assuntos
Compostos Organometálicos/química , Fosfolipídeos/síntese química , Rutênio/química , Estrutura Molecular , Oxirredução , Fosfolipídeos/química , Processos Fotoquímicos , Piridinas/química
13.
Soft Matter ; 11(34): 6852-8, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26234205

RESUMO

This investigation details the formation of polymer network trilayer laminates formed by thiol-X click chemistries, and their subsequent implementation and evaluation for quadruple shape memory behavior. Thiol-Michael addition and thiol-isocyanate-based crosslinking reactions were employed to fabricate each of the laminate's layers with independent control of the chemistry and properties of each layer and outstanding interlayer adhesion and stability. The characteristic features of step-growth thiol-X reactions, such as excellent network uniformity and narrow thermal transitions as well as their stoichiometric nature, enabled fabrication of trilayer laminates with three distinctly different glass transition temperatures grouped within a narrow range of 100 °C. Through variations in the layer thicknesses, a step-wise modulus drop as a function of temperature was achieved. This behavior allowed multi-step programming and the demonstration and quantification of quadruple shape memory performance. As is critical for this performance, the interface connecting the layers was evaluated in stoichiometric as well as off-stoichiometric systems. It was shown that the laminated structures exhibit strong interfacial binding and hardly suffer any delamination during cyclic material testing and deformation.


Assuntos
Química Click , Polimerização , Polímeros/química , Compostos de Sulfidrila/química , Adesividade , Fenômenos Mecânicos , Temperatura
14.
Tech Coloproctol ; 18(2): 137-43, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23818235

RESUMO

BACKGROUND: This study aimed to retrospectively assess the accuracy of minimal preparation computed tomography (MPCT) in the detection of colorectal cancer (CRC) within the frail and elderly population and to evaluate the relevance of extra-colonic findings (ECF). METHODS: Radiology reports, clinical notes and follow-up reports from 207 patients who underwent MPCT to investigate for CRC between 2005 and 2009 were analysed. Patients were scanned following the administration of oral contrast for 48 h, without bowel preparation or colonic insufflation. MPCT results were measured against patient outcomes, with a minimum of 2 years of follow-up. RESULTS: Twelve cases of clinically relevant CRC were confirmed (5.8 %). MPCT correctly identified 11 of these lesions (sensitivity 91.6 %). Thirty-one patients had a possible CRC identified by MPCT, which was not confirmed by further examination (specificity 84.1 %). This results in a positive predictive value of 26.2 % and a negative predictive value of 99.4 %. Five of the patients with colon cancer underwent curative surgery. Sixty-eight clinically relevant ECF were confirmed, including 14 previously undiagnosed extra-colonic malignancies. ECF were considered to account for the presenting complaint in 15.0 % (31/207) of all patients. CONCLUSIONS: Minimal preparation computed tomography is an effective and reliable investigation for the exclusion of clinically relevant CRC in this population. It provides clinicians with a valuable and pragmatic alternative to colonoscopy and CT colonography when invasive examination or cathartic bowel preparation will be poorly tolerated and small polyps are of limited significance. MPCT has an advantage over purely luminal imaging in the detection of extra-colonic pathology and appears to have an equally important role in the detection of CRC.


Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Idoso Fragilizado , Achados Incidentais , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Catárticos/administração & dosagem , Meios de Contraste/administração & dosagem , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Insuflação , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos
15.
Reprod Toxicol ; 41: 67-72, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23792114

RESUMO

To determine the sensitivity of male reproductive toxicity endpoints in NHPs we performed a power analysis of routine and triggered endpoints using control data from sexually mature Asian and Mauritian NHPs. The power to detect a 50% change from control was 13-30% for male reproductive organ weights, ∼30% for testicular volume, 6-66% for seminal analyses and 10-78% for male hormones. Overall, male reproductive endpoints have poor power (less than 80%) to detect a 50% change from control with a group size of 3 monkeys. Confidently identifying adverse male reproductive effects with these endpoints would likely require specialized study designs with larger group sizes. Triggering of non-routine endpoints in cases where there is special concern for male reproductive toxicity is unlikely to increase sensitivity to detect adverse effects.


Assuntos
Testes de Toxicidade/estatística & dados numéricos , Animais , Interpretação Estatística de Dados , Hormônio Foliculoestimulante , Genitália Masculina , Hormônio Luteinizante , Macaca fascicularis , Masculino , Tamanho do Órgão , Reprodução , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Testosterona
16.
Reprod Toxicol ; 38: 37-46, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23462583

RESUMO

Antibody-like biopharmaceuticals cross the placenta by utilizing transport pathways available for transfer of maternal antibodies to the conceptus. To characterize the timing and magnitude of this transfer in the rat, embryo/fetal biodistribution of maternally administered radiolabeled humanized IgG2 was quantified over the course of gestation using gamma counting and whole body autoradiography. The result was humanized IgG2 found in rat embryo/fetal tissues as early as gestation day 11 with a >1000-fold increase in the amount of total IgG2 by day 21. The concentration of IgG2 in rat embryo/fetal tissues generally remained unchanged from gestation day 11 to 17 with a slight increase from day 17 to 21. In addition, fetal-maternal tissue concentration ratios remained stable during organogenesis with a slight increase from gestation day 17 to 21. Based on the empirical amount of antibody present in the embryo/fetus during specific developmental windows, direct antibody binding to biological targets could potentially result in adverse developmental outcomes.


Assuntos
Anticorpos Monoclonais Humanizados/farmacocinética , Imunoglobulina G/farmacologia , Troca Materno-Fetal , Placenta/metabolismo , Animais , Anticorpos Monoclonais Humanizados/sangue , Autorradiografia , Embrião de Mamíferos/metabolismo , Feminino , Feto/metabolismo , Imunoglobulina G/sangue , Radioisótopos do Iodo , Gravidez , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
17.
HIV Med ; 14(2): 108-14, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23171088

RESUMO

OBJECTIVES: The aim of the study was to qualitatively and semiquantitatively characterize the expression of the principal HIV co-receptors chemokine (C-C motif) receptor 5 (CCR5) and chemokine (C-X-C motif) receptor 4 (CXCR4) on susceptible CD4 T-helper cell, monocyte/macrophage and Langerhans dendritic cell populations within the cervical epithelia of asymptomatic women attending a genitourinary medicine clinic. METHODS: Of 77 asymptomatic women recruited, 35 were excluded: 21 because they were found to have bacterial vaginosis, eight because they were found to have candida and six for other reasons. Cervical cytobrush samples from 11 women with Chlamydia trachomatis infection and 31 women without any detectable genital infection were stained with fluorescently labelled antibodies specific for cell surface CCR5, CXCR4, CD4, CD3, CD1a and CD19 expression, then analysed by flow cytometry. RESULTS: CD4/CD3 T-helper cells (84%), CD1a Langerhans dendritic cells (75%) and CD4/CD14 monocytes/macrophages (59%) were detected in the samples. CCR5 and CXCR4 HIV co-receptor expression was observed on 46-86% of the above subsets. CD1a cells exhibited significantly higher CCR5 and CXCR4 positivity and median fluorescence than CD4 cells and higher CXCR4 positivity and median fluorescence than CD14 cells (P < 0.05 or less). Increased detection of CCR5 over CXCR4 was seen in CD14 cells (P < 0.05). No significant differences in CCR5 or CXCR4 expression were found in samples from asymptomatic women with or without chlamydial infection. CONCLUSIONS: Co-receptor expression confirms the potential for CD1a Langerhans cells, monocytes/macrophages and T-helper cells in the cervix as primary targets for HIV infection. Previously observed selective transmission of CCR5-tropic isolates cannot be accounted for by a lack of CXCR4-expressing CD4 cervical immune cells. We were unable to identify any specific impact of chlamydial infection on co-receptor expression in this study.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Colo do Útero/imunologia , Células Dendríticas/imunologia , Soropositividade para HIV/imunologia , HIV-1/imunologia , Macrófagos/imunologia , Receptores CCR5/imunologia , Receptores CXCR4/imunologia , Adulto , Diferenciação Celular , Colo do Útero/patologia , Colo do Útero/virologia , Chlamydia trachomatis/isolamento & purificação , Feminino , Citometria de Fluxo , Soropositividade para HIV/patologia , HIV-1/fisiologia , Humanos , Subpopulações de Linfócitos T , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/microbiologia , Tropismo Viral , Replicação Viral , Saúde da Mulher
18.
Clin Pediatr (Phila) ; 51(12): 1150-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22930778

RESUMO

The breath-actuated nebulizer (BAN) is a new respiratory device to deliver short-acting ß-agonists to patients with asthma exacerbations. This pediatric convenience sample experimental study compares the BAN with conventional nebulizers and demonstrates that the BAN allows for shorter treatment times to achieve improved clinical asthma scores with less albuterol, shorter emergency department length of stay, and fewer hospitalizations.


Assuntos
Albuterol/administração & dosagem , Asma/tratamento farmacológico , Broncodilatadores/administração & dosagem , Nebulizadores e Vaporizadores , Administração por Inalação , Adolescente , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Feminino , Hospitalização , Humanos , Lactente , Tempo de Internação , Masculino , Estudos Prospectivos , Análise de Regressão , Índice de Gravidade de Doença , Resultado do Tratamento
19.
Reprod Toxicol ; 34(1): 66-72, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22543284

RESUMO

Embryo-fetal biodistribution of a maternally administered humanized IgG2 in rats was evaluated by enzyme-linked immunosorbent assay in dose response and time course studies. Fetal and maternal plasma IgG2 levels increased with dose from 10 to 300mg/kg but fetal:maternal ratio decreased with increasing dose. Plasma IgG2 levels decreased in fetal rat with increasing time post-dose but more slowly than maternal levels. This difference in post-dose kinetics resulted in an increased fetal:maternal ratio with increasing days since last dose. Lastly, IgG2 in embryo-fetal tissue was detected at very low levels on gestation day (GD) 10-12 and levels increased over 100-fold by GD 17. The profile of increasing IgG2 levels as gestation progressed continued in extra-embryonic fluid (GD 12-19) until the end of gestation in fetal plasma (GD 19-21). Based on the current study, there is a potential for direct effects on rat embryo-fetal development following maternal administration of a biopharmaceutical IgG2.


Assuntos
Anticorpos Monoclonais Humanizados/farmacocinética , Embrião de Mamíferos/metabolismo , Feto/metabolismo , Imunoglobulina G/farmacologia , Animais , Anticorpos Monoclonais Humanizados/sangue , Feminino , Imunoglobulina G/sangue , Troca Materno-Fetal , Organogênese/fisiologia , Gravidez , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
20.
J Hosp Infect ; 80(2): 122-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22196853

RESUMO

BACKGROUND: Infection control in hospitals and care homes remains a key issue. They are regularly inspected regarding standards of hygiene, but visual assessment does not necessarily correlate with microbial cleanliness. Pathogens can persist in the inanimate environment for extended periods of time. AIM: This prospective study compared the effectiveness of a novel sanitizer containing electrolysed water, in which the active ingredient is stabilized hypochlorous acid (Aqualution™), with the effectiveness of the quaternary ammonium disinfectant in current use for microbial removal from hand-touch surfaces in a care home. The study had a two-period crossover design. METHODS: Five surfaces were cleaned daily over a four-week period, with screening swabs taken before and after cleaning. Swabs were cultured in order to compare levels of surface microbial contamination [colony-forming units (cfu)/cm(2)] before and after cleaning with each product. FINDINGS: Cleaning with electrolysed water reduced the mean surface bacterial load from 2.6 [interquartile range (IQR) 0.30-30.40] cfu/cm(2) to 0.10 (IQR 0.10-1.40) cfu/cm(2) [mean log(10) reduction factor 1.042, 95% confidence interval (CI) 0.79-1.30]. Cleaning with the in-use quaternary ammonium disinfectant increased the bacterial load from 0.90 (IQR 0.10-8.50) cfu/cm(2) to 93.30 (IQR 9.85-363.65) cfu/cm(2) (mean log(10) reduction -1.499, 95% CI -1.87 to -1.12) (P < 0.0001). Using two proposed benchmark standards for surface microbial levels in hospitals, electrolysed water resulted in a higher 'pass rate' than the in-use quaternary ammonium disinfectant (80-86% vs 15-21%, P < 0.0001). CONCLUSION: Electrolysed water exerts a more effective bacterial kill than the in-use quaternary ammonium disinfectant, which suggests that it may be useful as a surface sanitizer in environments such as care homes.


Assuntos
Infecção Hospitalar/prevenção & controle , Desinfetantes/farmacologia , Desinfecção/métodos , Microbiologia Ambiental , Serviços de Assistência Domiciliar , Bactérias/isolamento & purificação , Contagem de Colônia Microbiana , Estudos Cross-Over , Humanos , Ácido Hipocloroso/farmacologia , Estudos Prospectivos , Compostos de Amônio Quaternário/farmacologia
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