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2.
Phys Eng Sci Med ; 46(4): 1791-1802, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37819450

RESUMO

Combined magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT) may enhance diagnosis, aid surgical planning and intra-operative orientation for prostate biopsy and radical prostatectomy. Although PET-MRI may provide these benefits, PET-MRI machines are not widely available. Image fusion of Prostate specific membrane antigen PET/CT and MRI acquired separately may be a suitable clinical alternative. This study compares CT-MR registration algorithms for urological prostate cancer care. Paired whole-pelvis MR and CT scan data were used (n = 20). A manual prostate CTV contour was performed independently on each patients MR and CT image. A semi-automated rigid-, automated rigid- and automated non-rigid registration technique was applied to align the MR and CT data. Dice Similarity Index (DSI), 95% Hausdorff distance (95%HD) and average surface distance (ASD) measures were used to assess the closeness of the manual and registered contours. The automated non-rigid approach had a significantly improved performance compared to the automated rigid- and semi-automated rigid-registration, having better average scores and decreased spread for the DSI, 95%HD and ASD (all p < 0.001). Additionally, the automated rigid approach had similar significantly improved performance compared to the semi-automated rigid registration across all accuracy metrics observed (all p < 0.001). Overall, all registration techniques studied here demonstrated sufficient accuracy for exploring their clinical use. While the fully automated non-rigid registration algorithm in the present study provided the most accurate registration, the semi-automated rigid registration is a quick, feasible, and accessible method to perform image registration for prostate cancer care by urologists and radiation oncologists now.


Assuntos
Próstata , Neoplasias da Próstata , Masculino , Humanos , Próstata/diagnóstico por imagem , Próstata/cirurgia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia Computadorizada por Raios X/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Pelve
3.
Chronic Illn ; 19(1): 56-64, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-34866419

RESUMO

OBJECTIVE: To explore the crisis of identity in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) through the lens of Communities of Practice. METHODS: A closed Facebook group was created to gather qualitative data from participants diagnosed with CFS/ME (n = 22). Data were analysed using a theoretical thematic analysis. RESULTS: The current research revealed the reality of enabling and disabling communities in the lived experience of CFS/ME and the role of participation in developing empowered identities. Learning how to be alongside CFS/ME aligned with participants' experiences of purpose and meaning. New identities may be developed which are not centrally defined by loss or stigma. DISCUSSION: Participation in supportive communities enables CFS/ME identities to emerge as a platform for positive change. Engaging with the CFS/ME virtual community may be a way for both families and health professionals to reflect on current practice.


Assuntos
Síndrome de Fadiga Crônica , Humanos , Pesquisa Qualitativa , Estigma Social
4.
PLoS One ; 17(4): e0266623, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35471999

RESUMO

Cancer is the leading cause of death in dogs, yet there are no established screening paradigms for early detection. Liquid biopsy methods that interrogate cancer-derived genomic alterations in cell-free DNA in blood are being adopted for multi-cancer early detection in human medicine and are now available for veterinary use. The CANcer Detection in Dogs (CANDiD) study is an international, multi-center clinical study designed to validate the performance of a novel multi-cancer early detection "liquid biopsy" test developed for noninvasive detection and characterization of cancer in dogs using next-generation sequencing (NGS) of blood-derived DNA; study results are reported here. In total, 1,358 cancer-diagnosed and presumably cancer-free dogs were enrolled in the study, representing the range of breeds, weights, ages, and cancer types seen in routine clinical practice; 1,100 subjects met inclusion criteria for analysis and were used in the validation of the test. Overall, the liquid biopsy test demonstrated a 54.7% (95% CI: 49.3-60.0%) sensitivity and a 98.5% (95% CI: 97.0-99.3%) specificity. For three of the most aggressive canine cancers (lymphoma, hemangiosarcoma, osteosarcoma), the detection rate was 85.4% (95% CI: 78.4-90.9%); and for eight of the most common canine cancers (lymphoma, hemangiosarcoma, osteosarcoma, soft tissue sarcoma, mast cell tumor, mammary gland carcinoma, anal sac adenocarcinoma, malignant melanoma), the detection rate was 61.9% (95% CI: 55.3-68.1%). The test detected cancer signal in patients representing 30 distinct cancer types and provided a Cancer Signal Origin prediction for a subset of patients with hematological malignancies. Furthermore, the test accurately detected cancer signal in four presumably cancer-free subjects before the onset of clinical signs, further supporting the utility of liquid biopsy as an early detection test. Taken together, these findings demonstrate that NGS-based liquid biopsy can offer a novel option for noninvasive multi-cancer detection in dogs.


Assuntos
Hemangiossarcoma , Osteossarcoma , Animais , Biomarcadores Tumorais/genética , Cães , Detecção Precoce de Câncer , Testes Hematológicos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Biópsia Líquida
5.
Polymers (Basel) ; 14(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35215676

RESUMO

To address the increasing demand for safe and effective treatment options for pelvic organ prolapse (POP) due to the worldwide ban of the traditional polypropylene meshes, this study introduced degradable polycaprolactone (PCL)/polyethylene glycol (PEG) composite meshes fabricated with melt-electrowriting (MEW). Two PCL/PEG mesh groups: 90:10 and 75:25 (PCL:PEG, wt%) were fabricated and characterized for their degradation rate and mechanical properties, with PCL meshes used as a control. The PCL/PEG composites showed controllable degradation rates by adjusting the PEG content and produced mechanical properties, such as maximal forces, that were higher than PCL alone. The antibacterial properties of the meshes were elicited by coating them with a commonly used antibiotic: azithromycin. Two dosage levels were used for the coating: 0.5 mg and 1 mg per mesh, and both dosage levels were found to be effective in suppressing the growth of S. aureus bacteria. The biocompatibility of the meshes was assessed using human immortalized adipose derived mesenchymal stem cells (hMSC). In vitro assays were used to assess the cell viability (LIVE/DEAD assay), cell metabolic activity (alamarBlue assay) and cell morphology on the meshes (fluorescent and electron microscopy). The cell attachment was found to decrease with increased PEG content. The freshly drug-coated meshes showed signs of cytotoxicity during the cell study process. However, when pre-released for 14 days in phosphate buffered saline, the initial delay in cell attachment on the drug-coated mesh groups showed full recovery at the 14-day cell culture time point. These results indicated that the PCL/PEG meshes with antibiotics coating will be an effective anti-infectious device when first implanted into the patients, and, after about 2 weeks of drug release, the mesh will be supporting cell attachment and proliferation. These meshes demonstrated a potential effective treatment option for POP that may circumvent the issues related to the traditional polypropylene meshes.

6.
BMJ Open ; 11(2): e045006, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33550265

RESUMO

INTRODUCTION: Cannabis use in Canada is becoming more prevalent across all demographic groups due to increases in accessibility and lowered perceptions of harm. These patterns are mirrored among women of reproductive age, including women who are pregnant. Given increasing evidence for detrimental short- and long-term impacts of cannabis exposure on fetal, newborn and child outcomes, there is a need for high-quality, accessible resources providing reliable guidance and recommendations on this topic for both the public and healthcare providers. We will conduct a scoping review to identify and characterise all publicly available online educational resources discussing cannabis use related to fertility, pregnancy and breastfeeding developed by Canadian organisations. METHODS AND ANALYSIS: Using Arksey and O'Malley's scoping review methodology as a guide, we will search Medline (Ovid), Medline in Process (Ovid), Embase (Ovid), ERIC (Ovid), CINAHL (EBSCOhost) and Education Source (EBSCOhost). We will also conduct a grey literature search targeting the websites of national and independent Canadian obstetrical societies and networks, and government and public health offices that provide recommendations or guidance to individuals and their healthcare providers seeking information on cannabis use related to fertility, pregnancy or breastfeeding. ETHICS AND DISSEMINATION: Research ethics approval is not required for scoping review studies. We anticipate that this review's findings will be disseminated through traditional channels, including preprint and peer-reviewed publications and presentations at academic conferences. In addition, the resources and guidelines identified in the study will be gathered and made available online on a single comprehensive public repository. PROTOCOL REGISTRATION NUMBER: osf.io/p24y5.


Assuntos
Aleitamento Materno , Cannabis , Canadá , Cannabis/efeitos adversos , Criança , Feminino , Fertilidade , Humanos , Recém-Nascido , Gravidez , Projetos de Pesquisa , Literatura de Revisão como Assunto
7.
Ann Behav Med ; 53(8): 756-768, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-30395147

RESUMO

BACKGROUND: The relationship between a clinician and their client-the "therapeutic alliance" is a robust predictor of outcome in healthcare settings; yet, few interventions to improve alliance have been tested. Motivational interviewing is a client-centered approach that embodies many principles and strategies consistent with a strong therapeutic alliance. PURPOSE: To examine whether alliance is enhanced by training dietitians to deliver a motivational interviewing informed health behavior change intervention ("Eating as Treatment"; EAT) as part of routine consultations with patients with head and neck cancer. The predictive ability of motivational interviewing techniques was also assessed. METHODS: A secondary analysis of the EAT stepped-wedge cluster-randomized controlled trial was conducted. Patients with head and neck cancer undergoing radiotherapy (n = 307) were treated by radiotherapy dietitians (n = 29) during the control (Treatment as Usual) or intervention (EAT) phase. Alliance was rated during the first and final weeks of radiotherapy, and again 4 and 12 weeks post-radiotherapy. Dietetic sessions were audiotaped. Week one sessions were objectively rated for dietitians' use of motivational interviewing techniques. RESULTS: Generalized linear-mixed effects regressions found no effect of EAT on dietitian-rated alliance (p = .237). After excluding outliers, patient-rated alliance was 0.29 points lower after EAT training (p = .016). Post hoc analyses revealed lower patient ratings on perceived support and dietitian confidence. Hierarchical multiple regressions found that no specific motivational interviewing techniques predicted patient-rated alliance. Dietitian acknowledgment of patient challenges was related to dietitian-rated alliance (ß =.15, p =.035). CONCLUSIONS: Patient and dietitian ratings of alliance were high after EAT training, but not significantly improved. Further research is needed to better understand the differential impact of intervention training and delivery on patient and clinician ratings of therapeutic alliance. CLINICAL TRIAL INFORMATION: Trial registration number ACTRN12613000320752.


Assuntos
Neoplasias de Cabeça e Pescoço/psicologia , Comportamentos Relacionados com a Saúde , Nutricionistas/psicologia , Aliança Terapêutica , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Entrevista Motivacional , Avaliação de Programas e Projetos de Saúde/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensino
8.
Proc Natl Acad Sci U S A ; 114(45): 12039-12044, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29078338

RESUMO

Membrane contact sites (MCS) are zones of contact between the membranes of two organelles. At MCS, specific proteins tether the organelles in close proximity and mediate the nonvesicular trafficking of lipids and ions between the two organelles. The endoplasmic reticulum (ER) integral membrane protein VAP is a common component of MCS involved in both tethering and lipid transfer by binding directly to proteins containing a FFAT [two phenylalanines (FF) in an acidic tract (AT)] motif. In addition to maintaining cell homeostasis, MCS formation recently emerged as a mechanism by which intracellular pathogens hijack cellular resources and establish their replication niche. Here, we investigated the mechanism by which the Chlamydia-containing vacuole, termed the inclusion, establishes direct contact with the ER. We show that the Chlamydia protein IncV, which is inserted into the inclusion membrane, displays one canonical and one noncanonical FFAT motif that cooperatively mediated the interaction of IncV with VAP. IncV overexpression was sufficient to bring the ER in close proximity of IncV-containing membranes. Although IncV deletion partially decreased VAP association with the inclusion, it did not suppress the formation of ER-inclusion MCS, suggesting the existence of redundant mechanisms in MCS formation. We propose a model in which IncV acts as one of the primary tethers that contribute to the formation of ER-inclusion MCS. Our results highlight a previously unidentified mechanism of bacterial pathogenesis and support the notion that cooperation of two FFAT motifs may be a common feature of VAP-mediated MCS formation. Chlamydia-host cell interaction therefore constitutes a unique system to decipher the molecular mechanisms underlying MCS formation.


Assuntos
Motivos de Aminoácidos/fisiologia , Proteínas de Bactérias/metabolismo , Chlamydia/metabolismo , Retículo Endoplasmático/metabolismo , Vacúolos/metabolismo , Sítios de Ligação/fisiologia , Proteínas de Transporte/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Retículo Endoplasmático/microbiologia , Células HEK293 , Células HeLa , Humanos , Corpos de Inclusão/metabolismo , Corpos de Inclusão/microbiologia , Proteínas de Membrana/metabolismo , Ligação Proteica/fisiologia , Transporte Proteico/fisiologia , Vacúolos/microbiologia , Proteínas de Transporte Vesicular/metabolismo
9.
Biochim Biophys Acta ; 1863(11): 2624-2636, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27496272

RESUMO

Our laboratory has recently demonstrated that low concentrations of ouabain increase blood pressure in rats associated with stimulation of NaK ATPase activity and activation of the Src signaling cascade in NHE1-dependent manner. Proteomic analysis of human kidney proximal tubule cells (HKC11) suggested that the Angiotensin II type 1 receptor (AT1R) as an ouabain-associating protein. We hypothesize that ouabain-induced stimulation of NaK ATPase activity is mediated through AT1R. To test this hypothesis, we examined the effect of ouabain on renal cell angiotensin II production, the effect of AT1R inhibition on ouabain-stimulated NKA activity, and the effect of ouabain on NKA-AT1R association. Ouabain increased plasma angiotensin II levels in rats treated with ouabain (1µg/kg body wt./day) for 9days and increased angiotensin II levels in cell culture media after 24h treatment with ouabain in human (HKC11), mouse (MRPT), and human adrenal cells. Ouabain 10pM stimulated NKA-mediated 86Rb uptake and phosphorylation of EGFR, Src, and ERK1/2. These effects were prevented by the AT1R receptor blocker candesartan. FRET and TIRF microscopy using Bodipy-labeled ouabain and mCherry-NKA or mCherry-AT1R demonstrated association of ouabain with AT1R and NKA. Further our FRET and TIRF studies demonstrated increased association between AT1R and NKA upon treatment with low dose ouabain. We conclude that ouabain stimulates NKA in renal proximal tubule cells through an angiotensin/AT1R-dependent mechanism and that this pathway contributes to cardiac glycoside associated hypertension.


Assuntos
Ativadores de Enzimas/farmacologia , Túbulos Renais Proximais/efeitos dos fármacos , Ouabaína/farmacologia , Receptor Tipo 1 de Angiotensina/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Angiotensina II/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Angiotensinogênio/metabolismo , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Ativação Enzimática , Ativadores de Enzimas/toxicidade , Hipertensão/induzido quimicamente , Hipertensão/enzimologia , Túbulos Renais Proximais/enzimologia , Camundongos , Ouabaína/toxicidade , Peptidil Dipeptidase A/metabolismo , Fosforilação , Ligação Proteica , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/genética , Transdução de Sinais/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/genética , Transfecção
10.
Sci Rep ; 6: 27806, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27291296

RESUMO

The spiroindolones, a new class of antimalarial medicines discovered in a cellular screen, are rendered less active by mutations in a parasite P-type ATPase, PfATP4. We show here that S. cerevisiae also acquires mutations in a gene encoding a P-type ATPase (ScPMA1) after exposure to spiroindolones and that these mutations are sufficient for resistance. KAE609 resistance mutations in ScPMA1 do not confer resistance to unrelated antimicrobials, but do confer cross sensitivity to the alkyl-lysophospholipid edelfosine, which is known to displace ScPma1p from the plasma membrane. Using an in vitro cell-free assay, we demonstrate that KAE609 directly inhibits ScPma1p ATPase activity. KAE609 also increases cytoplasmic hydrogen ion concentrations in yeast cells. Computer docking into a ScPma1p homology model identifies a binding mode that supports genetic resistance determinants and in vitro experimental structure-activity relationships in both P. falciparum and S. cerevisiae. This model also suggests a shared binding site with the dihydroisoquinolones antimalarials. Our data support a model in which KAE609 exerts its antimalarial activity by directly interfering with P-type ATPase activity.


Assuntos
Antimaláricos/metabolismo , Indóis/metabolismo , ATPases do Tipo-P/metabolismo , Compostos de Espiro/metabolismo , Sequência de Aminoácidos , Antimaláricos/química , Antimaláricos/farmacologia , Sítios de Ligação , Sistemas CRISPR-Cas/genética , Citosol/química , Citosol/efeitos dos fármacos , Farmacorresistência Fúngica , Indóis/química , Indóis/farmacologia , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , ATPases do Tipo-P/antagonistas & inibidores , ATPases do Tipo-P/genética , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/enzimologia , Estrutura Terciária de Proteína , ATPases Translocadoras de Prótons/antagonistas & inibidores , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/enzimologia , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNA , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Relação Estrutura-Atividade , Sequenciamento Completo do Genoma
11.
Front Neuroanat ; 9: 131, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26528144

RESUMO

BACKGROUND: An understanding of the maturation of auditory cortex responses in typically developing infants and toddlers is needed to later identify auditory processing abnormalities in infants at risk for neurodevelopmental disorders. The availability of infant and young child magnetoencephalography (MEG) systems may now provide near optimal assessment of left and right hemisphere auditory neuromagnetic responses in young populations. To assess the performance of a novel whole-head infant MEG system, a cross-sectional study examined the maturation of left and right auditory cortex responses in children 6- to 59-months of age. METHODS: Blocks of 1000 Hz (1st and 3rd blocks) and 500 Hz tones (2nd block) were presented while MEG data were recorded using an infant/young child biomagnetometer (Artemis 123). Data were obtained from 29 children (11 males; 6- to 59-months). Latency measures were obtained for the first positive-to-negative evoked response waveform complex in each hemisphere. Latency and age associations as well as frequency and hemisphere latency differences were examined. For the 1000 Hz tone, measures of reliability were computed. RESULTS: For the first response-a response with a "P2m" topography-latencies decreased as a function of age. For the second response-a response with a "N2m" topography-no N2m latency and age relationships were observed. A main effect of tone frequency showed earlier P2m responses for 1st 1000 Hz (150 ms) and 2nd 1000 Hz (148 ms) vs. 500 Hz tones (162 ms). A significant main effect of hemisphere showed earlier N2m responses for 2nd 1000 Hz (226 ms) vs. 1st 1000 Hz (241 ms) vs. 500 Hz tones (265 ms). P2m and N2m interclass correlation coefficient latency findings were as follows: left P2m (0.72, p < 0.001), right P2m (0.84, p < 0.001), left N2m (0.77, p < 0.001), and right N2m (0.77,p < 0.01). CONCLUSIONS: Findings of strong age and latency associations, sensitivity to tone frequency, and good test-retest reliability support the viability of longitudinal infant MEG studies that include younger as well as older participants as well as studies examining auditory processing abnormalities in infants at risk for neurodevelopmental disorders.

12.
Front Hum Neurosci ; 8: 99, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24624069

RESUMO

BACKGROUND: A major motivation in designing the new infant and child magnetoencephalography (MEG) system described in this manuscript is the premise that electrophysiological signatures (resting activity and evoked responses) may serve as biomarkers of neurodevelopmental disorders, with neuronal abnormalities in conditions such as autism spectrum disorder (ASD) potentially detectable early in development. Whole-head MEG systems are generally optimized/sized for adults. Since magnetic field produced by neuronal currents decreases as a function of distance(2) and infants and young children have smaller head sizes (and thus increased brain-to-sensor distance), whole-head adult MEG systems do not provide optimal signal-to-noise in younger individuals. This spurred development of a whole-head infant and young child MEG system - Artemis 123. METHODS: In addition to describing the design of the Artemis 123, the focus of this manuscript is the use of Artemis 123 to obtain auditory evoked neuromagnetic recordings and resting-state data in young children. Data were collected from a 14-month-old female, an 18-month-old female, and a 48-month-old male. Phantom data are also provided to show localization accuracy. RESULTS: Examination of Artemis 123 auditory data showed generalizability and reproducibility, with auditory responses observed in all participants. The auditory MEG measures were also found to be manipulable, exhibiting sensitivity to tone frequency. Furthermore, there appeared to be a predictable sensitivity of evoked components to development, with latencies decreasing with age. Examination of resting-state data showed characteristic oscillatory activity. Finally, phantom data showed that dipole sources could be localized with an error less than 0.5 cm. CONCLUSIONS: Artemis 123 allows efficient recording of high-quality whole-head MEG in infants four years and younger. Future work will involve examining the feasibility of obtaining somatosensory and visual recordings in similar-age children as well as obtaining recordings from younger infants. Thus, the Artemis 123 offers the promise of detecting earlier diagnostic signatures in such neurodevelopmental disorders.

13.
Biochim Biophys Acta ; 1843(6): 1089-102, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24566089

RESUMO

Recent studies suggest that at low concentrations, ouabain increases Na-K ATPase and NHE1 activity and activates the Src signaling cascade in proximal tubule cells. Our laboratory demonstrated that low concentrations of ouabain increase blood pressure in rats. We hypothesize that ouabain-induced increase in blood pressure and Na-K ATPase activity requires NHE1 activity and association. To test this hypothesis we treated rats with ouabain (1µgkg body wt(-1)day(-1)) for 9days in the presence or absence of the NHE1 inhibitor, zoniporide. Ouabain stimulated a significant increase in blood pressure which was prevented by zoniporide. Using NHE1-expressing Human Kidney cells 2 (HK2), 8 (HK8) and 11 (HK11) and Mouse Kidney cells from Wild type (WT) and NHE1 knock-out mice (SWE) cell lines, we show that ouabain stimulated Na-K ATPase activity and surface expression in a Src-dependent manner in NHE1-expressing cells but not in NHE1-deplete cells. Zoniporide prevented ouabain-induced stimulation of (86)Rb uptake in the NHE1-expressing cells. FRET and TIRF microscopy showed that ouabain increased association between GFP-NHE1 and mCherry-Na-K ATPase transfected into NHE1-deficient SWE cells. Mutational analysis demonstrated that the caveolin binding motif (CBM) of Na-K ATPase α1 is required for translocation of both Na-K ATPase α1 and NHE1 to the basolateral membrane. Mutations in activity or scaffold domains of NHE1 resulted in loss of ouabain-mediated regulation of Na-K ATPase. These results support that NHE1 is required for the ouabain-induced increase in blood pressure, and that the caveolin binding motif of Na-K ATPase α1 as well as the activity and scaffolding domains of NHE1 are required for their functional association.


Assuntos
Cardiotônicos/farmacologia , Proteínas de Transporte de Cátions/fisiologia , Túbulos Renais Proximais/efeitos dos fármacos , Ouabaína/farmacologia , Trocadores de Sódio-Hidrogênio/fisiologia , ATPase Trocadora de Sódio-Potássio/química , ATPase Trocadora de Sódio-Potássio/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Biotinilação , Pressão Sanguínea/efeitos dos fármacos , Western Blotting , Caveolina 1/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Transferência Ressonante de Energia de Fluorescência , Humanos , Hidrólise , Técnicas Imunoenzimáticas , Transporte de Íons/efeitos dos fármacos , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/metabolismo , Masculino , Camundongos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Trocador 1 de Sódio-Hidrogênio , Quinases da Família src/metabolismo
14.
Am J Physiol Renal Physiol ; 304(8): F1076-85, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23344572

RESUMO

The acute inhibitory effects of parathyroid hormone (PTH) on proximal tubule Na(+)-K(+)-ATPase (Na-K) and sodium-dependent phosphate (NaPi) transport have been extensively studied, while little is known about the chronic effects of PTH. Patients with primary hyperparathyroidism, a condition characterized by chronic elevations in PTH, exhibit persistent hypophosphatemia but not significant evidence of salt wasting. We postulate that chronic PTH stimulation results in differential desensitization of PTH responses. To address this hypothesis, we compared the effects of chronic PTH stimulation on Na-P(i) cotransporter (Npt2a) expression and Na-K activity and expression in Sprague Dawley rats, transgenic mice featuring parathyroid-specific cyclin D1 overexpression (PTH-D1), and proximal tubule cell culture models. We demonstrated a progressive decrease in brush-border membrane (BBM) expression of Npt2a from rats treated with PTH for 6 h or 4 days, while Na-K expression and activity in the basolateral membranes (BLM) exhibited an initial decrease followed by recovery to control levels by 4 days. Npt2a protein expression in PTH-D1 mice was decreased relative to control animals, whereas levels of Na-K, NHERF-1, and PTH receptor remained unchanged. In PTH-D1 mice, NpT2a mRNA expression was reduced by 50% relative to control mice. In opossum kidney proximal tubule cells, PTH decreased Npt2a mRNA levels. Both actinomycin D and cycloheximide treatment prevented the PTH-mediated decrease in Npt2a mRNA, suggesting that the PTH response requires transcription and translation. These findings suggest that responses to chronic PTH exposure are selectively regulated at a posttranscriptional level. The persistence of the phosphaturic response to PTH occurs through posttranscriptional mechanisms.


Assuntos
Hipofosfatemia/genética , Túbulos Renais Proximais/fisiologia , Hormônio Paratireóideo/metabolismo , Estabilidade de RNA/fisiologia , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIa/genética , Animais , Células Cultivadas , Ciclina D1/genética , Ciclina D1/metabolismo , Modelos Animais de Doenças , Hipofosfatemia/metabolismo , Córtex Renal/citologia , Córtex Renal/fisiologia , Túbulos Renais Proximais/citologia , Camundongos , Camundongos Transgênicos , Gambás , Hormônio Paratireóideo/farmacologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Processamento Pós-Transcricional do RNA/efeitos dos fármacos , Processamento Pós-Transcricional do RNA/fisiologia , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismo , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIa/metabolismo
15.
Hum Pathol ; 43(5): 650-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22137423

RESUMO

Schwannoma is a rare gastrointestinal mesenchymal tumor, as the vast majority of gastric mesenchymal tumors are gastrointestinal stromal tumors. In this study, we analyzed clinicopathologically 51 gastric schwannomas. These tumors predominantly occurred in older adults with a marked female predominance (40 women and 11 men; median and mean ages, 60 and 58 years). They variably presented with gastric discomfort, bleeding, or rarely gastric outlet obstruction; and many were incidental findings during other medical procedures. The tumors ranged from 1 to 10.5 cm (median, 4.5 cm). The typical histologic features included spindle cells usually with microtrabecular architecture and focal nuclear atypia, and peritumoral lymphoid cuff, whereas features of soft tissue schwannomas, such as encapsulation, nuclear palisading, vascular hyalinization, and dilatation, were absent or infrequent. Median mitotic count was 2/50 high-power fields, with the highest count being 13/50 high-power fields. No malignant variants were recognized, and long-term follow-up did not reveal recurrences or metastases. Immunohistochemically, all examined tumors were S100 protein positive and most were also GFAP positive, whereas CD34 and NF68 were encountered rarely and all tumors were negative for HMB45, KIT, DOG1/Ano 1, smooth muscle actin, desmin, and synaptophysin. None of the 9 tumors studied contained gastrointestinal stromal tumor-specific KIT or PDGFRA mutations. Fluorescence in situ hybridization studies revealed multiple signals with BCR probe (chromosome 22) and centromeric probes for chromosomes 2 and 18 suggesting polyploidy. These findings indicate that gastric schwannoma is a distinctive form of peripheral nerve sheath tumor that in many ways differs from soft tissue schwannoma. It should be distinguished from gastrointestinal stromal tumor and other mesenchymal tumors of the gastrointestinal tract, such as the S100 protein-positive gastrointestinal clear cell sarcoma and metastatic melanoma.


Assuntos
Neurilemoma/patologia , Neoplasias Gástricas/patologia , Estômago/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Feminino , Mucosa Gástrica/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Neurilemoma/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Proteínas S100/metabolismo , Fatores Sexuais , Neoplasias Gástricas/metabolismo
16.
J Am Anim Hosp Assoc ; 46(2): 91-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20194363

RESUMO

This study reviews rim excision as a treatment for canine acanthomatous ameloblastomas (CAA) in dogs with <3 mm of bone involvement. Removal of a canine tooth was involved in 47% of the cases; 33% cases involved the caudal dentition. Follow-up ranged from 3 months to 5 years. No evidence of recurrence was seen. Client satisfaction with cosmesis and the animal's ability to masticate was judged to be good. With appropriate case selection, rim excision appears to be a viable option for CAA and results in improved dental occlusion, cosmesis, and no evidence of epulis recurrence.


Assuntos
Ameloblastoma/veterinária , Doenças do Cão/cirurgia , Neoplasias Gengivais/veterinária , Ameloblastoma/patologia , Ameloblastoma/cirurgia , Animais , Doenças do Cão/patologia , Cães , Feminino , Seguimentos , Gengiva/patologia , Gengiva/cirurgia , Neoplasias Gengivais/patologia , Neoplasias Gengivais/cirurgia , Masculino , Mandíbula/patologia , Mandíbula/cirurgia , Neoplasias Mandibulares/patologia , Neoplasias Mandibulares/cirurgia , Neoplasias Mandibulares/veterinária , Maxila/patologia , Maxila/cirurgia , Neoplasias Maxilares/patologia , Neoplasias Maxilares/cirurgia , Neoplasias Maxilares/veterinária , Extração Dentária/veterinária , Resultado do Tratamento
17.
Fetal Pediatr Pathol ; 27(4-5): 197-205, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18800262

RESUMO

We reviewed our 20-year experience with infant acute lymphoblastic leukemia (ALL). Nine infants (4.2% of all ALL) were identified; all were < 6 months of age. White blood cell counts ranged from 42,000-1.6 million/microL, 6 of 8 had hepatosplenomegaly, and 6 of 9 (66.6%) had central nervous system disease. Of 7 with cytogenetic information, 6 (85.7%) had diploidy; the remaining child was 47, XY,+8,del(21)(q22). Four had the MLL-11q23 abnormality. All received chemotherapy. Four underwent stem cell transplantation. Survival was 67%, (15 months-21 years). Deaths occurred at 9 months, 15 months (graft vs. host), and 7 years (complications of small bowel transplantation). Only 1 undergoing stem cell transplantation died. There were no late recurrences or second malignancies. Despite extensive disease and age < 6 months at diagnosis (a poor prognostic feature), for ALL patients our 67% survival is at least as good as reported, although it is less favorable than childhood ALL.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Hospitais Universitários , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Condicionamento Pré-Transplante , Doença Aguda , Cromossomos Humanos Par 11 , Humanos , Lactente , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
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