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1.
S Afr Med J ; 114(2): e1538, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38525575

RESUMO

Determining the death burden for prioritising public health interventions necessitates detailed data on the causal pathways to death. Postmortem minimally invasive tissue sampling (MITS), incorporating histology, molecular and microbial culture diagnostics, enhances cause-of-death attribution, particularly for infectious deaths. MITS proves a valid alternative to full diagnostic autopsies, especially in low- and middle-income countries. In Soweto, South Africa (SA), the Child Health and Mortality Prevention Surveillance (CHAMPS) programme has delineated over 1 000 child and stillbirth deaths since 2017. This SA CHAMPS site supports advocating for the use of postmortem MITS as routine practice, for more granular insights into under-5 mortality causes. This knowledge is crucial for SA's pursuit of Sustainable Development Goal 3.2, targeting reduced neonatal and under-5 mortality rates. This commentary explores the public health advantages and ethicolegal considerations surrounding implementing MITS as standard of care for stillbirths, neonatal and paediatric deaths in SA. Furthermore, based on the data from CHAMPS, we present three pragmatic algorithmic approaches to the wide array of testing options for cost-effectiveness and scalability of postmortem MITS in South African state facilities.


Assuntos
Mortalidade da Criança , Padrão de Cuidado , Criança , Recém-Nascido , Gravidez , Feminino , Humanos , África do Sul , Causas de Morte , Natimorto , Autopsia
2.
AIDS Behav ; 27(12): 3970-3980, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37318665

RESUMO

We assessed the prevalence and correlates of alcohol use among 870 people who inject drugs living with HIV in Kenya, with attention toward (1) sexual and injecting risk behaviors for HIV transmission and (2) HIV care engagement. We defined heavy alcohol use as > 14 drinks/week for men and > 7 drinks/week for women, moderate alcohol use as any lesser but non-zero amount, and any alcohol use as either moderate or heavy use. Approximately 39% of participants reported any alcohol use and 15% heavy use. In multivariate analysis, any alcohol use compared to no use was associated with needle sharing, > 3 new sex partners in the past 3 months, being unaware of HIV status, never enrolling in HIV care, and not being on ART (all p < 0.05). Heavy alcohol use as compared to no use was associated with needle sharing (aOR = 2.72; 95% CI 1.43, 5.13), injection equipment sharing (aOR = 1.80; 95% CI 1.00, 3.16), > 3 new sex partners in the past 3 months (aOR = 1.99; 95% CI 1.12, 3.49), and being unaware of HIV status (aOR = 2.77; 95% CI 1.46, 5.19). There was no association between any measure of alcohol use and unsuppressed viral load. Alcohol use among people who inject drugs living with HIV may carry elevated risk of HIV transmission mediated by sexual and injecting practices and is associated with lower engagement in multiple stages of the HIV care cascade.

3.
Int J Obstet Anesth ; 53: 103613, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36564271

RESUMO

BACKGROUND: Previous research has shown that, in comparison with non-pregnant women of reproductive age, pregnant women with COVID-19 are more likely to be admitted to critical care, receive invasive ventilation, and die. At present there are limited data in relation to outcomes and healthcare utilisation following hospital discharge of pregnant and recently pregnant women admitted to critical care. METHODS: A national cohort study of pregnant and recently pregnant women who were admitted to critical care in Scotland with confirmed or suspected COVID-19. We examined hospital outcomes as well as hospital re-admission rates. RESULTS: Between March 2020 and March 2022, 75 pregnant or recently pregnant women with laboratory-confirmed COVID-19 were admitted to 24 Intensive Care Units across Scotland. Almost two thirds (n=49, 65%) were from the most deprived socio-economic areas. Complete 90-day acute hospital re-admission data were available for 74 (99%) patients. Nine (12%) women required an emergency non-obstetric hospital re-admission within 90 days. Less than 5% of the cohort had received any form of vaccination. CONCLUSIONS: This national cohort study has demonstrated that pregnant or recently pregnant women admitted to critical care with COVID-19 were more likely to reside in areas of socio-economic deprivation, and fewer than 5% of the cohort had received any form of vaccination. More targeted public health campaigning across the socio-economic gradient is urgently required.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Gravidez , Feminino , Humanos , Masculino , Estudos de Coortes , Unidades de Terapia Intensiva , Cuidados Críticos , Escócia/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/terapia
4.
Anaesthesia ; 77(9): 971-980, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35820195

RESUMO

Using a cohort study design, we analysed 17 diagnoses and 9 interventions (including critical care admission) as a composite measure of severe maternal morbidity for pregnancies recorded over 14 years in Scotland. There were 762,918 pregnancies, of which 7947 (10 in 1000 pregnancies) recorded 9345 severe maternal morbidity events, 2802 episodes of puerperal sepsis being the most common (30%). Severe maternal morbidity incidence increased from 9 in 1000 pregnancies in 2012 to 17 in 1000 pregnancies in 2018, due in part to puerperal sepsis recording. The odds ratio (95%CI) for severe maternal morbidity was higher for: older women, for instance 1.22 (1.13-1.33) for women aged 35-39 years and 1.44 (1.27-1.63) for women aged > 40 years compared with those aged 25-29 years; obese women, for instance 1.13 (1.06-1.21) for BMI 30-40 kg.m-2 and 1.32 (1.15-1.51) for BMI > 40 kg.m-2 compared with BMI 18.5-24.9 kg.m-2 ; multiple pregnancy, 2.39 (2.09-2.74); and previous caesarean delivery, 1.52 (1.40-1.65). The median (IQR [range]) hospital stay was 3 (2-5 [1-8]) days with severe maternal morbidity and 2 (1-3 [1-5]) days without. Forty-one women died during pregnancy or up to 42 days after delivery, representing mortality rates per 100,000 pregnancies of about 365 with severe maternal morbidity and 1.6 without. There were 1449 women admitted to critical care, 807 (58%) for mechanical ventilation or support of at least two organs. We recorded an incidence of severe maternal morbidity higher than previously published, possibly because sepsis was coded inaccurately in our databases. Further research may determine the value of this composite measure of severe maternal morbidity.


Assuntos
Hospitalização , Sepse , Idoso , Estudos de Coortes , Feminino , Humanos , Incidência , Tempo de Internação , Mortalidade Materna , Morbidade , Gravidez , Sepse/epidemiologia
5.
Osteoarthritis Cartilage ; 30(8): 1130-1139, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35569801

RESUMO

OBJECTIVE: Focal lesions within the subchondral bone, termed subchondral bone cysts (SBCs), are clinically accepted radiographic markers of advanced osteoarthritis (OA), but their etiology in the hip is not well understood. DESIGN: This study used micro-computed tomography (µCT), and histological and immunocytological analysis to examine the prevalence, size, location, and morphological and cellular features of SBCs found within 34 femoral heads (14 male, 20 female; age range = 43-80 years) obtained from total hip arthroplasty procedures. RESULTS: SBCs were common-present in 91% of the femoral heads examined-and frequently commuted with the surface of the femoral head, but otherwise showed no preferred anatomical location. Few associations were found between SBC features and patient characteristics such as BMI, age and sex. SBCs were also heterogenous in composition, ranging from fibrous (most common) to predominantly fatty (least common) and often containing vasculature, nerve fibers, cartilage islands, and bony spicules. Despite this heterogeneity, focal abnormalities in bone density and cartilage thickness were consistently observed. Bone adjacent to SBCs was denser than that in the primary compressive group, and cartilage thickness in regions overlying SBCs was lower than in non-overlying regions. In contrast to these local bony changes, µCT-based finite element analyses indicated that the stiffness of the primary compressive group was only mildly affected by SBCs. CONCLUSIONS: These findings indicate that SBCs in the femoral head involve extensive perturbations in cellular activity, culminating in myriad skeletal tissue types and spatially heterogenous changes in bone and cartilage morphology that are likely to affect OA progression.


Assuntos
Cistos Ósseos , Cartilagem Articular , Osteoartrite do Quadril , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistos Ósseos/diagnóstico por imagem , Cistos Ósseos/patologia , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Feminino , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/diagnóstico por imagem , Osteoartrite do Quadril/patologia , Microtomografia por Raio-X
6.
S Afr Med J ; 111(6): 544-549, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-34382563

RESUMO

Pregnant women are at greater risk of severe COVID-19 than non-pregnant women. Despite limited safety data on use of COVID-19 vaccines in pregnancy, many international societies have recommended their use when pregnant women are at particularly high risk of acquiring COVID-19, or have suggested that vaccines should not be withheld from pregnant women where no other contraindications to COVID-19 vaccination exist. A number of vaccines, including those against influenza, tetanus and pertussis, have been shown to reduce both maternal and infant morbidity and mortality when used antenatally. We explore the role of COVID-19 vaccination in the setting of pregnancy, discuss the limited data available, and summarise current international guidelines.


Assuntos
Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Vacinação/métodos , COVID-19/virologia , Vacinas contra COVID-19/efeitos adversos , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/virologia , Índice de Gravidade de Doença , Vacinação/efeitos adversos
7.
J Control Release ; 327: 140-149, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-32707210

RESUMO

The potential of microporous zeolites FAU and BEA, and mesoporous MCM-41, for prolonged release of atenolol in drug delivery systems was investigated both experimentally, using drug release studies, and theoretically using classical molecular dynamics simulations. Remarkably, zero-order release of atenolol was achieved from FAU (SiO2:Al2O3 = 80:1) into phosphate buffer for 24 h followed by prolonged release for at least another 48 h. Experimental data also demonstrate the ability for all of the drug-zeolite combinations investigated to achieve prolonged release of atenolol, with the release rates determined by the combination of framework topology, aluminium content and drug release study media. Molecular dynamics simulations give an insight into the reasons for the different release rates observed for FAU and BEA. The results of this work emphasise the need for sophisticated models in order to explain subtle differences in release, such as those observed at different SiO2:Al2O3 ratios.


Assuntos
Zeolitas , Atenolol , Sistemas de Liberação de Medicamentos , Dióxido de Silício
8.
QJM ; 111(11): 769-778, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30016493

RESUMO

BACKGROUND: Tumor-associated macrophages (TAMs) are important determinants of intratumoral immune evasion, neoangiogenesis, extracellular matrix remodeling and dysregulated tumor cell proliferation. Our prior studies revealed that macrophage-derived, but not tumor cell-derived, macrophage migration inhibitory factor (MIF), is an important determinant of TAM alternative activation and M2 polarization. AIM: Because MIF is historically thought to initiate signaling via a receptor-dependent, outside-in mode of action, we wished to investigate the specific contributions of tumor-derived vs. macrophage-derived MIF to M2 marker expression during macrophage polarization. DESIGN: Murine oral squamous cell-carcinoma cells (SCCVII) were co-cultured with either the RAW 264.7 mouse macrophage cell line or mouse primary bone marrow-derived macrophages in the context of MIF genetic loss/inhibition individually or in combination each cell type. METHODS: Twelve well Transwell plates were used to co-culture SCCVII cells and RAW 264.7, MIF+/+ or MIF-/- macrophages treated with/without the small molecule MIF inhibitor, 4-iodo-6-phenylpyrimidine and incubated in the presence or absence of interleukin (IL-4) for 48 h. Macrophages were analyzed by quantitative real-time polymerase chain reaction and/or immunoblotting for relative macrophage polarization marker expression. RESULTS: IL-4 treatment synergizes with SCCVII co-culture in inducing the expression of macrophage M2 markers and loss or inhibition of macrophage-derived MIF significantly reduces both IL-4 alone and IL-4/SCCVII co-culture-induced macrophage M2 marker expression. CONCLUSION: These studies identify an important and dominant requirement for macrophage MIF in maximal Th2-cytokine and oral squamous carcinoma cell-induced macrophage polarization and M2 marker expression.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Macrófagos/citologia , Animais , Carcinoma de Células Escamosas/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Técnicas de Cocultura , Interleucina-4/farmacologia , Oxirredutases Intramoleculares/antagonistas & inibidores , Fatores Inibidores da Migração de Macrófagos/antagonistas & inibidores , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neovascularização Patológica/metabolismo , Pirimidinas/farmacologia , Células RAW 264.7
9.
BMC Bioinformatics ; 19(1): 2, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29291710

RESUMO

BACKGROUND: To evaluate statistical methods for genome-wide genetic analyses, one needs to be able to simulate realistic genotypes. We here describe a method, applicable to a broad range of association study designs, that can simulate autosome-wide single-nucleotide polymorphism data with realistic linkage disequilibrium and with spiked in, user-specified, single or multi-SNP causal effects. RESULTS: Our construction uses existing genome-wide association data from unrelated case-parent triads, augmented by including a hypothetical complement triad for each triad (same parents but with a hypothetical offspring who carries the non-transmitted parental alleles). We assign offspring qualitative or quantitative traits probabilistically through a specified risk model and show that our approach destroys the risk signals from the original data. Our method can simulate genetically homogeneous or stratified populations and can simulate case-parents studies, case-control studies, case-only studies, or studies of quantitative traits. We show that allele frequencies and linkage disequilibrium structure in the original genome-wide association sample are preserved in the simulated data. We have implemented our method in an R package (TriadSim) which is freely available at the comprehensive R archive network. CONCLUSION: We have proposed a method for simulating genome-wide SNP data with realistic linkage disequilibrium. Our method will be useful for developing statistical methods for studying genetic associations, including higher order effects like epistasis and gene by environment interactions.


Assuntos
Simulação por Computador , Estudo de Associação Genômica Ampla/métodos , Genótipo , Desequilíbrio de Ligação , Modelos Genéticos , Polimorfismo de Nucleotídeo Único , Algoritmos , Alelos , Estudos de Casos e Controles , Frequência do Gene , Estudos de Associação Genética , Humanos , Fenótipo
10.
Benef Microbes ; 8(4): 563-567, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28726512

RESUMO

Human milk oligosaccharides (HMOs) are structurally diverse unconjugated glycans with a composition unique to each lactating mother. While HMOs have been shown to have an impact on the development of infant gut microbiota, it is not well known if HMOs also already affect milk microbial composition. To address this question, we analysed eleven colostrum samples for HMO content by high-pressure liquid chromatography and microbiota composition by quantitative PCR. Higher total HMO concentration was associated with higher counts of Bifidobacterium spp. (ρ=0.63, P=0.036). A distinctive effect was seen when comparing different HMO groups: positive correlations were observed between sialylated HMOs and Bifidobacterium breve (ρ=0.84, P=0.001), and non-fucosylated/non-sialylated HMOs and Bifidobacterium longum group (ρ=0.65, P=0.030). In addition to associations between HMOs and bifidobacteria, positive correlations were observed between fucosylated HMOs and Akkermansia muciniphila (ρ=0.70, P=0.017), and between fucosylated/sialylated HMOs and Staphylococcus aureus (ρ=0.75, P=0.007). Our results suggest that the characterised HMOs have an effect on specific microbial groups in human milk. Both oligosaccharides and microbes provide a concise inoculum for the compositional development of the infant gut microbiota.


Assuntos
Bactérias/isolamento & purificação , Colostro/microbiologia , Microbiota , Leite Humano/química , Oligossacarídeos/análise , Bactérias/classificação , Bactérias/genética , Colostro/química , Fezes/microbiologia , Feminino , Humanos , Lactente , Recém-Nascido , Lactação , Masculino , Leite Humano/microbiologia , Probióticos/administração & dosagem
11.
Vet Pathol ; 53(6): 1204-1209, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27154544

RESUMO

Recurrent outbreaks of sudden death and bloody diarrhea were reported in March 2013 and February 2014 in a breeding colony of Papillon dogs. During the first outbreak, 1 adult dog and 2 eight-month-old puppies died. During the second outbreak, 2 ten-week-old puppies died. One puppy from the first outbreak and 2 puppies from the second outbreak were examined at necropsy. Histologically, all 3 puppies had severe segmental crypt necrosis of the small intestine and marked lymphoid follicle depletion in the spleen and Peyer's patches. Real-time (RT) polymerase chain reaction (PCR) demonstrated abundant canine parvovirus (CPV-2) DNA (Ct<15) in the affected small intestine, and immunohistochemistry detected large amounts of CPV-2 antigen in intestinal crypt epithelium and Kupffer cells but few positive macrophages in lymphoid organs. All puppies had marked sinusoidal histiocytosis and multifocal granulomatous inflammation in mesenteric lymph nodes and spleen, prompting additional RT-PCR testing for canine circovirus 1 (CaCV-1). Very high levels of CaCV-1 DNA (Ct<13) were detected in small intestine, lymph nodes, and spleen. In situ hybridization for CaCV-1 detected rare positive nuclei of regenerating crypt epithelium but abundant amounts of CaCV-1 nucleic acid in the cytoplasm and nuclei of histiocytes in all lymphoid tissues, including granulomatous inflammatory foci and hepatic Kupffer cells. Significant levels of CaCV-1 DNA were detected in blood and serum (Ct as low as 13) but not feces from 3 surviving dogs at 2 months or 1 year after the outbreak, respectively. We hypothesize that CPV-2 infection predisposed dogs to CaCV-1 infection and ultimately resulted in more severe clinical disease.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus , Coinfecção/veterinária , Doenças do Cão/virologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino , Animais , Infecções por Circoviridae/complicações , Infecções por Circoviridae/virologia , Coinfecção/virologia , Surtos de Doenças/veterinária , Cães , Intestino Delgado/patologia , Intestino Delgado/virologia , Células de Kupffer/patologia , Células de Kupffer/virologia , Infecções por Parvoviridae/complicações , Infecções por Parvoviridae/virologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Recidiva
12.
Colorectal Dis ; 17(9): 748-61, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25891148

RESUMO

AIM: Restaging imaging by MRI or endorectal ultrasound (ERUS) following neoadjuvant chemoradiotherapy is not routinely performed, but the assessment of response is becoming increasingly important to facilitate individualization of management. METHOD: A search of the MEDLINE and Scopus databases was performed for studies that evaluated the accuracy of restaging of rectal cancer following neoadjuvant chemoradiotherapy with MRI or ERUS against the histopathological outcome. A systematic review of selected studies was performed. The methodological quality of studies that qualified for meta-analysis was critically assessed to identify studies suitable for inclusion in the meta-analysis. RESULTS: Sixty-three articles were included in the systematic review. Twelve restaging MRI studies and 18 restaging ERUS studies were eligible for meta-analysis of T-stage restaging accuracy. Overall, ERUS T-stage restaging accuracy (mean [95% CI]: 65% [56-72%]) was nonsignificantly higher than MRI T-stage accuracy (52% [44-59%]). Restaging MRI is accurate at excluding circumferential resection margin involvement. Restaging MRI and ERUS were equivalent for prediction of nodal status: the accuracy of both investigations was 72% with over-staging and under-staging occurring in 10-15%. CONCLUSION: The heterogeneity amongst restaging studies is high, limiting conclusive findings regarding their accuracies. The accuracy of restaging imaging is different for different pathological T stages and highest for T3 tumours. Morphological assessment of T- or N-stage by MRI or ERUS is currently not accurate or consistent enough for clinical application. Restaging MRI appears to have a role in excluding circumferential resection margin involvement.


Assuntos
Endossonografia , Imageamento por Ressonância Magnética , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Quimiorradioterapia Adjuvante , Humanos , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasias Retais/diagnóstico por imagem
13.
J Antimicrob Chemother ; 70(6): 1751-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25652750

RESUMO

OBJECTIVES: SMT19969 is a novel antimicrobial under clinical development for the treatment of Clostridium difficile infection (CDI). The objective was to determine the comparative susceptibility of 82 C. difficile clinical isolates (which included ribotype 027 isolates and isolates with reduced metronidazole susceptibility) to SMT19969, fidaxomicin, vancomycin and metronidazole and to determine the killing kinetics and post-antibiotic effects of SMT19969, fidaxomicin and vancomycin against C. difficile. METHODS: MICs were determined by agar incorporation. Killing kinetics and post-antibiotic effects were determined against C. difficile BI1, 630 and 5325 (ribotypes 027, 012 and 078, respectively). RESULTS: SMT19969 showed potent inhibition of C. difficile (MIC90=0.125 mg/L) and was markedly more active than either metronidazole (MIC90 = 8 mg/L) or vancomycin (MIC90 = 2 mg/L). There were no differences in susceptibility to SMT19969 between different ribotypes. Fidaxomicin was typically one doubling dilution more active than SMT19969 and both agents maintained activity against isolates with reduced susceptibility to metronidazole. In addition, SMT19969 was bactericidal against the C. difficile strains tested, with reductions in viable counts to below the limit of detection by 24 h post-inoculation. Vancomycin was bacteriostatic against all three strains. Fidaxomicin was bactericidal although reduced killing was observed at concentrations <20 × MIC against C. difficile BI1 (ribotype 027) compared with other strains tested. CONCLUSIONS: These data demonstrate that SMT19969 is associated with potent and bactericidal activity against the strains tested and support further investigation of SMT19969 as potential therapy for CDI.


Assuntos
Antibacterianos/farmacologia , Benzimidazóis/farmacologia , Clostridioides difficile/efeitos dos fármacos , Clostridioides difficile/fisiologia , Viabilidade Microbiana/efeitos dos fármacos , Piridinas/farmacologia , Clostridioides difficile/crescimento & desenvolvimento , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/microbiologia , Humanos , Testes de Sensibilidade Microbiana
14.
Vet Pathol ; 52(4): 668-75, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25487412

RESUMO

Inflammatory bowel disease (IBD) and intestinal lymphoma are intestinal disorders in dogs, both causing similar chronic digestive signs, although with a different prognosis and different treatment requirements. Differentiation between these 2 conditions is based on histopathologic evaluation of intestinal biopsies. However, an accurate diagnosis is often difficult based on histology alone, especially when only endoscopic biopsies are available to differentiate IBD from enteropathy-associated T-cell lymphoma (EATL) type 2, a small cell lymphoma. The purpose of this study was to evaluate the utility of histopathology; immunohistochemistry (IHC) for CD3, CD20, and Ki-67; and polymerase chain reaction (PCR) for antigen receptor rearrangement (T-cell clonality) in the differential diagnosis of severe IBD vs intestinal lymphoma. Endoscopic biopsies from 32 dogs with severe IBD or intestinal lymphoma were evaluated. The original diagnosis was based on microscopic examination of hematoxylin and eosin (HE)-stained sections alone followed by a second evaluation using morphology in association with IHC for CD3 and CD20 and a third evaluation using PCR for clonality. Our results show that, in contrast to feline intestinal lymphomas, 6 of 8 canine small intestinal lymphomas were EATL type 1 (large cell) lymphomas. EATL type 2 was uncommon. Regardless, in dogs, intraepithelial lymphocytes were not an important diagnostic feature to differentiate IBD from EATL as confirmed by PCR. EATL type 1 had a significantly higher Ki-67 index than did EATL type 2 or IBD cases. Based on the results of this study, a stepwise diagnostic approach using histology as the first step, followed by immunophenotyping and determining the Ki67 index and finally PCR for clonality, improves the accuracy of distinguishing intestinal lymphoma from IBD in dogs.


Assuntos
Doenças do Cão/patologia , Doenças Inflamatórias Intestinais/veterinária , Neoplasias Intestinais/veterinária , Antígeno Ki-67/metabolismo , Linfoma/veterinária , Animais , Antígenos CD20/metabolismo , Biópsia/veterinária , Complexo CD3/metabolismo , Diagnóstico Diferencial , Doenças do Cão/metabolismo , Cães , Feminino , Imuno-Histoquímica/veterinária , Imunofenotipagem/veterinária , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/patologia , Intestinos/patologia , Linfoma/metabolismo , Linfoma/patologia , Masculino , Linfócitos T/imunologia
15.
Biomed Res Int ; 2014: 350504, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25276779

RESUMO

Cochlear implants have provided hearing to hundreds of thousands of profoundly deaf people around the world. Recently, the eligibility criteria for cochlear implantation have been relaxed to include individuals who have some useful residual hearing. These recipients receive inputs from both electric and acoustic stimulation (EAS). Implant recipients who can combine these hearing modalities demonstrate pronounced benefit in speech perception, listening in background noise, and music appreciation over implant recipients that rely on electrical stimulation alone. The mechanisms bestowing this benefit are unknown, but it is likely that interaction of the electric and acoustic signals in the auditory pathway plays a role. Protection of residual hearing both during and following cochlear implantation is critical for EAS. A number of surgical refinements have been implemented to protect residual hearing, and the development of hearing-protective drug and gene therapies is promising for EAS recipients. This review outlines the current field of EAS, with a focus on interactions that are observed between these modalities in animal models. It also outlines current trends in EAS surgery and gives an overview of the drug and gene therapies that are clinically translatable and may one day provide protection of residual hearing for cochlear implant recipients.


Assuntos
Estimulação Acústica/tendências , Implante Coclear/efeitos adversos , Estimulação Elétrica , Regulação da Expressão Gênica , Terapia Genética , Perda Auditiva/etiologia , Humanos
16.
J Neural Eng ; 11(4): 046008, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24921595

RESUMO

OBJECTIVE: Cochlear implants (CIs) have provided some auditory function to hundreds of thousands of people around the world. Although traditionally carried out only in profoundly deaf patients, the eligibility criteria for implantation have recently been relaxed to include many partially-deaf patients with useful levels of hearing. These patients receive both electrical stimulation from their implant and acoustic stimulation via their residual hearing (electro-acoustic stimulation; EAS) and perform very well. It is unclear how EAS improves speech perception over electrical stimulation alone, and little evidence exists about the nature of the interactions between electric and acoustic stimuli. Furthermore, clinical results suggest that some patients that undergo cochlear implantation lose some, if not all, of their residual hearing, reducing the advantages of EAS over electrical stimulation alone. A reliable animal model with clinically-relevant partial deafness combined with clinical CIs is important to enable these issues to be studied. This paper outlines such a model that has been successfully used in our laboratory. APPROACH: This paper outlines a battery of techniques used in our laboratory to generate, validate and examine an animal model of partial deafness and chronic CI use. MAIN RESULTS: Ototoxic deafening produced bilaterally symmetrical hearing thresholds in neonatal and adult animals. Electrical activation of the auditory system was confirmed, and all animals were chronically stimulated via adapted clinical CIs. Acoustic compound action potentials (CAPs) were obtained from partially-hearing cochleae, using the CI amplifier. Immunohistochemical analysis allows the effects of deafness and electrical stimulation on cell survival to be studied. SIGNIFICANCE: This animal model has applications in EAS research, including investigating the functional interactions between electric and acoustic stimulation, and the development of techniques to maintain residual hearing following cochlear implantation. The ability to record CAPs via the CI has clinical direct relevance for obtaining objective measures of residual hearing.


Assuntos
Estimulação Acústica/métodos , Implantes Cocleares , Estimulação Elétrica/métodos , Transtornos da Audição/terapia , Desenho de Prótese , Potenciais de Ação/fisiologia , Animais , Animais Recém-Nascidos , Limiar Auditivo/fisiologia , Gatos , Cóclea/patologia , Audição/fisiologia , Transtornos da Audição/induzido quimicamente , Transtornos da Audição/patologia , Emissões Otoacústicas Espontâneas , Implantação de Prótese
17.
Phys Chem Chem Phys ; 16(30): 15825-30, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24676385

RESUMO

Recent synthetic work has realized a novel (n-type) small-molecule acceptor, 7,8,15,16-tetra-aza-terrylene (TAT), single-crystals of which can be grown oriented along the c-axis crystallographic direction, and over-coated with pentacene to form a highly ordered donor/acceptor interface for use in organic photovoltaic devices. However, characterization of single TAT crystals reveals highly variable emission spectra and excited state dynamics - properties which strongly influence photovoltaic performance. Through the use of single-crystal widefield imaging, photoluminescence spectroscopy, time correlated single photon counting, and resonant Raman studies, we conclude that this variability is a result of long-lived low-energy trap-emission from packing defects. Interestingly, we also discovered that TAT crystals whose width exceeds ∼200 nm begin acting as waveguides and optical microcavity resonators for their own photoluminescence. Several strategies are proposed for leveraging the size-dependant optical properties of TAT pillars to further enhance device performance using this active layer design.


Assuntos
Compostos Aza/química , Processos Fotoquímicos , Semicondutores , Análise Espectral/métodos
18.
Ann Oncol ; 25(5): 968-74, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24567366

RESUMO

BACKGROUND: Treatment options for wild-type BRAF melanoma patients remain limited. Selumetinib, a MEK 1/2 inhibitor, suppresses pERK levels independent of BRAF and NRAS mutation status, and combination with docetaxel has demonstrated synergy in xenograft models. The aim of this study was to assess the efficacy and safety of selumetinib plus docetaxel as first-line treatment in patients with wild-type BRAF advanced melanoma. PATIENTS AND METHODS: In this double-blind multicentre phase II trial patients with wild-type BRAF melanoma were randomized (1:1) to docetaxel with selumetinib or placebo. Docetaxel 75 mg/m(2) was administered intravenously every 3 weeks up to six cycles. Selumetinib 75 mg or placebo was given orally twice daily until disease progression or unacceptable toxicity. The primary end point was progression-free survival (PFS). Tumour NRAS mutation status was analysed retrospectively and correlated with treatment outcomes. RESULTS: Eighty-three patients were randomized to docetaxel plus selumetinib (n = 41) or docetaxel plus placebo (n = 42). The PFS hazard ratio (HR) (selumetinib:placebo) was 0.75 [90% confidence interval (CI) 0.50-1.14; P = 0.130], with a median PFS of 4.23 months (90% CI 3.63-6.90) for docetaxel plus selumetinib and 3.93 months (90% CI 2.07-4.16) for docetaxel alone. There was no significant difference in overall survival. The objective response rate was 32% with selumetinib versus 14% with placebo (P = 0.059). In a retrospective subset analysis, NRAS mutation status did not affect significantly upon clinical outcomes in either arm. The combination of docetaxel and selumetinib could be administered effectively to patients with metastatic melanoma, although the combination was less well tolerated than docetaxel alone. CONCLUSIONS: The combination of docetaxel with selumetinib showed no significant improvement in PFS compared with docetaxel alone, although more patients showed a response to combination therapy. We found no evidence to support using tumour NRAS mutation as a basis for selecting patients for combined MEK inhibitor and chemotherapy. CLINICAL TRIAL: DOC-MEK (EudraCT no: 2009-018153-23).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Melanoma/tratamento farmacológico , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/tratamento farmacológico , Idoso , Benzimidazóis/administração & dosagem , Análise Mutacional de DNA , Intervalo Livre de Doença , Docetaxel , Método Duplo-Cego , GTP Fosfo-Hidrolases/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Melanoma/secundário , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Taxoides/administração & dosagem , Resultado do Tratamento
19.
Vet Pathol ; 51(1): 238-56, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24129897

RESUMO

Veterinary pathology of infectious, particularly viral, and neoplastic diseases has advanced significantly with the advent of newer molecular methodologies that can detect nucleic acid of infectious agents within microscopic lesions, differentiate neoplastic from nonneoplastic cells, or determine the suitability of a targeted therapy by detecting specific mutations in certain cancers. Polymerase chain reaction-based amplification of DNA or RNA and in situ hybridization are currently the most commonly used methods for nucleic acid detection. In contrast, the main methodology used for protein detection within microscopic lesions is immunohistochemistry. Other methods that allow for analysis of nucleic acids within a particular cell type or individual cells, such as laser capture microdissection, are also available in some laboratories. This review gives an overview of the factors that influence the accurate analysis of nucleic acids in formalin-fixed tissues, as well as of different approaches to detect such targets.


Assuntos
Doenças dos Animais/diagnóstico , DNA Viral/isolamento & purificação , Neoplasias/veterinária , Patologia Molecular/métodos , Patologia Veterinária/métodos , Viroses/veterinária , Doenças dos Animais/genética , Doenças dos Animais/virologia , Animais , DNA Viral/análise , Formaldeído/efeitos adversos , Imuno-Histoquímica/veterinária , Hibridização In Situ/veterinária , Microdissecção e Captura a Laser/veterinária , Mutação , Neoplasias/diagnóstico , Neoplasias/genética , Reação em Cadeia da Polimerase/veterinária , Prognóstico , Fixação de Tecidos/veterinária , Viroses/diagnóstico
20.
Hear Res ; 306: 37-45, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24055621

RESUMO

The mouse is becoming an increasingly attractive model for auditory research due to the number of genetic deafness models available. These genetic models offer the researcher an array of congenital causes of hearing impairment, and are therefore of high clinical relevance. To date, the use of mice in cochlear implant research has not been possible due to the lack of an intracochlear electrode array and stimulator small enough for murine use, coupled with the difficulty of the surgery in this species. Here, we present a fully-implantable intracochlear electrode stimulator assembly designed for chronic implantation in the mouse. We describe the surgical approach for implantation, as well as presenting the first functional data obtained from intracochlear electrical stimulation in the mouse.


Assuntos
Implante Coclear , Implantes Cocleares , Estimulação Elétrica/métodos , Animais , Vias Auditivas , Limiar Auditivo/fisiologia , Tronco Encefálico/fisiologia , Cóclea/fisiologia , Surdez/induzido quimicamente , Surdez/reabilitação , Modelos Animais de Doenças , Eletrodos Implantados , Desenho de Equipamento , Audição , Camundongos , Camundongos Endogâmicos C57BL , Neomicina/efeitos adversos , Estribo/irrigação sanguínea
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