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1.
J Biol Chem ; 299(1): 102745, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36436558

RESUMO

Nudix hydrolase 7 (NUDT7) is an enzyme that hydrolyzes CoA species, is highly expressed in the liver, and resides in the peroxisomes. Peroxisomes are organelles where the preferential oxidation of dicarboxylic fatty acids occurs and where the hepatic synthesis of the primary bile acids cholic acid and chenodeoxycholic acid is completed. We previously showed that liver-specific overexpression of NUDT7 affects peroxisomal lipid metabolism but does not prevent the increase in total liver CoA levels that occurs during fasting. We generated Nudt7-/- mice to further characterize the role that peroxisomal (acyl-)CoA degradation plays in the modulation of the size and composition of the acyl-CoA pool and in the regulation of hepatic lipid metabolism. Here, we show that deletion of Nudt7 alters the composition of the hepatic acyl-CoA pool in mice fed a low-fat diet, but only in males fed a Western diet does the lack of NUDT7 activity increase total liver CoA levels. This effect is driven by the male-specific accumulation of medium-chain dicarboxylic acyl-CoAs, which are produced from the ß-oxidation of dicarboxylic fatty acids. We also show that, under conditions of elevated synthesis of chenodeoxycholic acid derivatives, Nudt7 deletion promotes the production of tauromuricholic acid, decreasing the hydrophobicity index of the intestinal bile acid pool and increasing fecal cholesterol excretion in male mice. These findings reveal that NUDT7-mediated hydrolysis of acyl-CoA pathway intermediates in liver peroxisomes contributes to the regulation of dicarboxylic fatty acid metabolism and the composition of the bile acid pool.


Assuntos
Ácidos e Sais Biliares , Dieta Ocidental , Animais , Masculino , Camundongos , Acil Coenzima A/metabolismo , Ácidos e Sais Biliares/metabolismo , Ácido Quenodesoxicólico , Ácidos Graxos/metabolismo , Fígado/metabolismo , Oxirredução , Nudix Hidrolases
2.
Am J Pathol ; 192(1): 160-177, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34710383

RESUMO

Sigma 1 receptor (Sigmar1) is a widely expressed, multitasking molecular chaperone protein that plays functional roles in several cellular processes. Mutations in the Sigmar1 gene are associated with several distal neuropathies with strong manifestation in skeletal muscle dysfunction with phenotypes like muscle wasting and atrophy. However, the physiological function of Sigmar1 in skeletal muscle remains unknown. Herein, the physiological role of Sigmar1 in skeletal muscle structure and function in gastrocnemius, quadriceps, soleus, extensor digitorum longus, and tibialis anterior muscles was determined. Quantification of myofiber cross-sectional area showed altered myofiber size distribution and changes in myofiber type in the skeletal muscle of the Sigmar1-/- mice. Interestingly, ultrastructural analysis by transmission electron microscopy showed the presence of abnormal mitochondria, and immunostaining showed derangements in dystrophin localization in skeletal muscles from Sigmar1-/- mice. In addition, myopathy in Sigmar1-/- mice was associated with an increased number of central nuclei, increased collagen deposition, and fibrosis. Functional studies also showed reduced endurance and exercise capacity in the Sigmar1-/- mice without any changes in voluntary locomotion, markers for muscle denervation, and muscle atrophy. Overall, this study shows, for the first time, a potential physiological function of Sigmar1 in maintaining healthy skeletal muscle structure and function.


Assuntos
Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Receptores sigma/deficiência , Animais , Colágeno/metabolismo , Distrofina/metabolismo , Fibrose , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/ultraestrutura , Condicionamento Físico Animal , Transporte Proteico , Receptores sigma/metabolismo , Receptor Sigma-1
3.
J Head Trauma Rehabil ; 38(3): E233-E243, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36731011

RESUMO

OBJECTIVE: To examine clinician perspectives regarding the use of telehealth for concussion assessment and management. SETTING: A Pan-Canadian survey. PARTICIPANTS: Twenty-five purposively sampled multidisciplinary clinician-researchers with concussion expertise (female, n = 21; physician, n = 11; and other health professional, n = 14). DESIGN: Sequential mixed-method design: (1) electronic survey and (2) semistructured interviews with focus groups via videoconference. Qualitative descriptive design. MAIN OUTCOME MEASURES: Survey : A 59-item questionnaire regarding the suitability of telehealth to perform recommended best practice components of concussion assessment and management. Focus groups : 10 open-ended questions explored survey results in more detail. RESULTS: Clinicians strongly agreed that telehealth could be utilized to obtain a clinical history (96%), assess mental status (88%), and convey a diagnosis (83%) on initial assessment; to take a focused clinical history (80%); to monitor functional status (80%) on follow-up; and to manage symptoms using education on rest (92%), planning and pacing (92%), and sleep recommendations (91%); and to refer to a specialist (80%). Conversely, many clinicians believed telehealth was unsuitable to perform a complete neurologic examination (48%), cervical spine (38%) or vestibular assessment (61%), or to provide vestibular therapy (21%) or vision therapy (13%). Key benefits included convenience, provision of care, and patient-centered approach. General and concussion-specific challenges included technology, quality of care, patient and clinician characteristics, and logistics. Strategies to overcome identified challenges are presented. CONCLUSIONS: From the perspective of experienced clinicians, telehealth is suited to manage symptomatic concussion patients presenting without red flags or following an initial in-person assessment, but may have limitations in ruling out serious pathology or providing return-to-sport clearance without an in-person physical examination.


Assuntos
Concussão Encefálica , Telemedicina , Humanos , Feminino , Canadá , Concussão Encefálica/diagnóstico , Concussão Encefálica/terapia , Volta ao Esporte , Exame Neurológico
4.
Molecules ; 28(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36771126

RESUMO

The proprotein convertase subtilisin kexin type 9 (PCSK9) emerged as a molecular target of great interest for the management of cardiovascular disorders due to its ability to reduce low density lipoprotein (LDL) cholesterol by binding and targeting at LDLR for lysosomal degradation in cells. Preliminary studies revealed that pseurotin A (PsA), a spiro-heterocyclic γ-lactam alkaloid from several marine and terrestrial Aspergillus and Penicillium species, has the ability to dually suppress the PCSK9 expression and protein-protein interaction (PPI) with LDLR, resulting in an anti-hypercholesterolemic effect and modulating the oncogenic role of PCSK9 axis in breast and prostate cancers progression and recurrence. Thus, a preliminary assessment of the PsA acute toxicity represents the steppingstone to develop PsA as a novel orally active PCSK9 axis modulating cancer recurrence inhibitor. PsA studies for in vitro toxicity on RWPE-1 and CCD 841 CoN human non-tumorigenic prostate and colon cells, respectively, indicated a cellular death shown at a 10-fold level of its reported anticancer activity. Moreover, a Western blot analysis revealed a significant downregulation of the pro-survival marker Bcl-2, along with the upregulation of the proapoptotic Bax and caspases 3/7, suggesting PsA-mediated induction of cell apoptosis at very high concentrations. The Up-and-Down methodology determined the PsA LD50 value of >550 mg/kg in male and female Swiss albino mice. Animals were orally administered single doses of PsA at 10, 250, and 500 mg/kg by oral gavage versus vehicle control. Mice were observed daily for 14 days with special care over the first 24 h after dosing to monitor any abnormalities in their behavioral, neuromuscular, and autonomic responses. After 14 days, the mice were euthanized, and their body and organ weights were recorded and collected. Mice plasma samples were subjected to comprehensive hematological and biochemical analyses. Collected mouse organs were histopathologically examined. No morbidity was detected following the PsA oral dosing. The 500 mg/kg female dosing group showed a 45% decrease in the body weight after 14 days but displayed no other signs of toxicity. The 250 mg/kg female dosing group had significantly increased serum levels of liver transaminases AST and ALT versus vehicle control. Moreover, a modest upregulation of apoptotic markers was observed in liver tissues of both animal sexes at 500 mg/kg dose level. However, a histopathological examination revealed no damage to the liver, kidneys, heart, brain, or lungs. While these findings suggest a possible sex-related toxicity at higher doses, the lack of histopathological injury implies that single oral doses of PsA, up to 50-fold the therapeutic dose, do not cause acute organ toxicity in mice though further studies are warranted.


Assuntos
Artrite Psoriásica , Neoplasias da Próstata , Masculino , Camundongos , Humanos , Animais , Pró-Proteína Convertase 9 , Serina Endopeptidases/metabolismo , Pró-Proteína Convertases/metabolismo , Próstata/metabolismo , Receptores de LDL/metabolismo , Neoplasias da Próstata/tratamento farmacológico
5.
Nurs Crit Care ; 27(3): 410-418, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34387920

RESUMO

AIMS: To develop a questionnaire to identify Intensive Care survivor needs at key transitions during the recovery process, and assess its validity and reliability in a group of ICU survivors. METHODS: Development of the Support Needs After ICU (SNAC) questionnaire was based on a systematic scoping review, and analysis of patient interviews (n = 22). Face and content validity were assessed by service users (n = 12) and an expert panel of healthcare professionals (n = 6). A pilot survey among 200 ICU survivors assessed recruitment at one of five different stages after ICU discharge [(1) in hospital, (2) < 6 weeks, (3) 7 weeks to 6 months, (4) 7 to 12 months, or (5) 12 to 24 months post-hospital discharge]; to assess reliability of the SNAC questionnaire; and to conduct exploratory data analysis. Reliability was determined using Cronbach's alpha for internal consistency; intraclass correlation coefficients for test-retest reliability. We explored correlations with sociodemographic variables using Pearson's correlation coefficient; differences between questionnaire scores and patient demographics using one-way ANOVA. RESULTS: The SNAC questionnaire consisted of 32 items that assessed five categories of support needs (informational, emotional, instrumental [e.g. practical physical help, provision of equipment or training], appraisal [e.g. clinician feedback on recovery] and spiritual needs). ICU survivors were recruited from Northern Ireland, England and Scotland. From a total of 375 questionnaires distributed, 202 (54%) were returned. The questionnaire had high internal consistency (0.97) and high test-retest reliability (r = 0.8) with subcategories ranging from 0.3 to 0.9. CONCLUSIONS: The SNAC questionnaire appears to be a comprehensive, valid, and reliable questionnaire. Further research will enable more robust examination of its properties e.g. factor analysis, and establish its utility in identifying whether patients' support needs evolve over time. RELEVANCE TO CLINICAL PRACTICE: The SNAC questionnaire has the potential to be used to identify ICU survivors' needs and inform post-hospital support services.


Assuntos
Unidades de Terapia Intensiva , Sobreviventes , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários , Sobreviventes/psicologia
6.
Am J Physiol Cell Physiol ; 321(6): C964-C977, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34586897

RESUMO

Pulmonary microvascular endothelial cells (PMVECs) uniquely express an α1G-subtype of voltage-gated T-type Ca2+ channel. We have previously revealed that the α1G channel functions as a background Ca2+ entry pathway that is critical for the cell proliferation, migration, and angiogenic potential of PMVECs, a novel function attributed to the coupling between α1G-mediated Ca2+ entry and constitutive Akt phosphorylation and activation. Despite this significance, mechanism(s) that link the α1G-mediated Ca2+ entry to Akt phosphorylation remain incompletely understood. In this study, we demonstrate that Ca2+/calmodulin-dependent protein kinase (CaMK) 4 serves as a downstream effector of the α1G-mediated Ca2+ entry to promote the angiogenic potential of PMVECs. Notably, CaMK2 and CaMK4 are both expressed in PMVECs. Pharmacological blockade or genetic knockdown of the α1G channel led to a significant reduction in the phosphorylation level of CaMK4 but not the phosphorylation level of CaMK2. Pharmacological inhibition as well as genetic knockdown of CaMK4 significantly decreased cell proliferation, migration, and network formation capacity in PMVECs. However, CaMK4 inhibition or knockdown did not alter Akt phosphorylation status in PMVECs, indicating that α1G/Ca2+/CaMK4 is independent of the α1G/Ca2+/Akt pathway in sustaining the cells' angiogenic potential. Altogether, these findings suggest a novel α1G-CaMK4 signaling complex that regulates the Ca2+-dominated angiogenic potential in PMVECs.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Sinalização do Cálcio , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/metabolismo , Cálcio/metabolismo , Células Endoteliais/enzimologia , Pulmão/irrigação sanguínea , Microvasos/enzimologia , Neovascularização Fisiológica , Inibidores da Angiogênese/farmacologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Proteína Quinase Tipo 4 Dependente de Cálcio-Calmodulina/genética , Movimento Celular , Proliferação de Células , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Masculino , Microvasos/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Ratos Sprague-Dawley
7.
Arch Toxicol ; 95(8): 2883-2889, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34148101

RESUMO

The International Agency for Research on Cancer (IARC) has recently proposed employing "ten key characteristics of human carcinogens" (TKCs) to determine the potential of agents for harmful effects. The TKCs seem likely to confuse the unsatisfactory correlation from testing regimes that have ignored the differences evident when cellular changes are compared in short and long-lived species, with their very different stem cell and somatic cell phylogenies. The proposed characteristics are so broad that their use will lead to an increase in the current unacceptably high rate of false positives. It could be an informative experiment to take well-established approved therapeutics with well-known human safety profiles and test them against this new TKC paradigm. Cancers are initiated and driven by heritable and transient changes in gene expression, expand clonally, and progress via additional associated acquired mutations and epigenetic alterations that provide cells with an evolutionary advantage. The genotoxicity testing protocols currently employed and required by regulation, emphasize testing for the mutational potential of the test agent. Two-year, chronic rodent cancer bioassays are intended to test for the entire spectrum of carcinogenic transformation. The use of cytotoxic doses causing increased, sustained cell proliferation that facilitates accumulated genetic damage leads to a high false-positive rate of tumor induction. Current cancer hazard assessment protocols and weight-of-the-evidence analysis of agent-specific cancer risk align poorly with the pathogenesis of human carcinoma and so need modernization and improvement in ways suggested here.


Assuntos
Carcinogênese/induzido quimicamente , Carcinógenos/toxicidade , Neoplasias/induzido quimicamente , Animais , Testes de Carcinogenicidade/métodos , Carcinógenos/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Testes de Mutagenicidade/métodos , Medição de Risco , Roedores , Sensibilidade e Especificidade
8.
Palliat Support Care ; 19(5): 615-630, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33308368

RESUMO

OBJECTIVES: Despite improving survival rates, people with advanced cancer face several physical and psychosocial concerns. Leisure-time physical activity (LPA) has been found to be beneficial after cancer diagnosis, but little is known about the current state of research exploring LPA in advanced cancer. Our objectives were to (a) map the literature examining LPA in people with advanced cancer, (b) report on the terms used to describe the advanced cancer population within the literature, and (c) examine how the concept of LPA is operationalized within the literature. METHOD: Our scoping review followed Arksey and O'Malley's methodological framework. We performed a search of 11 electronic databases and supplementary sources (February 2018; database search updated January 2020). Two reviewers independently reviewed and selected articles according to the inclusion criteria: English-language journal articles on original primary research studies exploring LPA in adults diagnosed with advanced cancer. Descriptive and thematic analyses were performed. RESULTS: Ninety-two articles met our criteria. Most included studies were published in the last decade (80%) and used quantitative methods (77%). Many study populations included mixed (40%), breast (21%), or lung (17%) cancers. Stages 3-4 or metastatic disease were frequently indicated to describe study populations (77%). Several studies (68%) described LPA programs or interventions. Of these, 78% involved structured aerobic/resistance exercise, while 16% explored other LPA types. SIGNIFICANCE OF RESULTS: This review demonstrates a recent surge in research exploring LPA in advanced cancer, particularly studies examining exercise interventions with traditional quantitative methods. There remains insufficient knowledge about patient experiences and perceptions toward LPA. Moreover, little is known about other leisure activities (e.g., Tai Chi, dance, and sports) for this population. To optimize the benefits of LPA in people with advanced cancer, research is needed to address the gaps in the current literature and to develop personalized, evidence-based supportive care strategies in cancer care.


Assuntos
Neoplasias , Exercício Físico , Humanos , Atividades de Lazer
9.
Breast Cancer Res Treat ; 180(3): 809-817, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32170635

RESUMO

BACKGROUND: Genomic tests are increasingly being used by clinicians when considering adjuvant chemotherapy for patients with oestrogen receptor-positive (ER+), human epidermal growth factor 2-negative (HER2-) breast cancer. The Oncotype DX breast recurrence score assay was the first test available in the UK National Health Service. This study looked at how UK clinicians were interpreting Recurrence Scores (RS) in everyday practice. METHODS: RS, patient and tumour characteristics and adjuvant therapy details were retrospectively collected for 713 patients from 14 UK cancer centres. Risk by RS-pathology-clinical (RSPC) was calculated and compared to the low/intermediate/risk categories, both as originally defined (RS < 18, 18-30 and > 30) and also using redefined boundaries (RS < 11, 11-25 and > 25). RESULTS: 49.8%, 36.2% and 14% of patients were at low (RS < 18), intermediate (RS 18-30) and high (RS > 30) risk of recurrence, respectively. Overall 26.7% received adjuvant chemotherapy. 49.2% of those were RS > 30; 93.3% of patients were RS > 25. Concordance between RS and RSPC improved when intermediate risk was defined as RS 11-25. CONCLUSIONS: This real-world data demonstrate the value of genomic tests in reducing the use of adjuvant chemotherapy in breast cancer. Incorporating clinical characteristics or RSPC scores gives additional prognostic information which may also aid clinicians' decision making.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Tomada de Decisão Clínica , Recidiva Local de Neoplasia/tratamento farmacológico , Guias de Prática Clínica como Assunto/normas , Projetos de Pesquisa , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Feminino , Seguimentos , Perfilação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Reino Unido
10.
Pharmacol Res ; 158: 104847, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32438039

RESUMO

Hypercholesterolemia has been documented to drive hormone-dependent breast cancer (BC) progression and resistance to hormonal therapy. Proprotein convertase subtilisin/kexin type-9 (PCSK9) regulates cholesterol metabolism through binding to LDL receptor (LDLR) and targeting the receptor for lysosomal degradation. Inhibition of PCSK9 is an established strategy to treat hypercholesterolemia. Pseurotin A (PS) is a unique spiro-heterocyclic γ-lactam alkaloid isolated from the fungus Aspergillus fumigatus. Preliminary studies indicated that PS lowered PCSK9 secretion in cultured HepG2 hepatocellular carcinoma cells, with an IC50 value of 1.20 µM. Docking studies suggested the ability of PS to bind at the PCSK9 narrow interface pocket that accommodates LDLR. Surface plasmon resonance (SPR) showed PS ability to inhibit the PCSK9-LDLR interaction at a concentration range of 10-150 µM. PS showed in vitro dose-dependent reduction of PCSK9, along with increased LDLR levels in hormone-dependent BT-474 and T47D breast cancer (BC) cell lines. In vivo, daily oral 10 mg/kg PS suppressed the progression of the hormone-dependent BT-474 BC cells in orthotopic nude mouse xenograft model. Immunohistochemistry (IHC) investigation of BT-474 breast tumor tissue proved the PS ability to reduce PCSK9 expression. PS also effectively suppressed BT-474 BC cells locoregional recurrence after primary tumor surgical excision. Western blot analysis showed decreased PCSK9 expression in liver tissues of PS-treated mice compared to vehicle-treated control group. PS treatment significantly reduced PCSK9 expression and normalized LDLR levels in collected primary and recurrent breast tumors at the study end. PS-treated mice showed reduced plasma cholesterol and 17ß-estradiol levels. Inhibition of tumor recurrence was associated with significant reductions in plasma level of the human BC recurrence marker CA 15-3 in treated mice at the study end. Histopathological examination of various PS-treated mice organs indicated lack of metastatic tumor cells and any pathological changes. The results of this study provide the first evidence for the suppression of the hormone-dependent breast tumor progression and recurrence by targeting the PCSK9-LDLR axis. PS is a novel first-in-class PCSK9-targeting lead appropriate for the use to control hormone-dependent BC progression and recurrence.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Pró-Proteína Convertase 9/metabolismo , Pirrolidinonas/farmacologia , Receptores de LDL/efeitos dos fármacos , Animais , Antibióticos Antineoplásicos/uso terapêutico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Colesterol/sangue , Progressão da Doença , Relação Dose-Resposta a Droga , Estradiol/sangue , Feminino , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Nus , Estrutura Molecular , Pró-Proteína Convertase 9/efeitos dos fármacos , Pirrolidinonas/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Am J Physiol Cell Physiol ; 316(3): C353-C364, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30649917

RESUMO

Pulmonary microvascular endothelial cells (PMVECs) display a rapid angioproliferative phenotype, essential for maintaining homeostasis in steady-state and promoting vascular repair after injury. Although it has long been established that endothelial cytosolic Ca2+ ([Ca2+]i) transients are required for proliferation and angiogenesis, mechanisms underlying such regulation and the transmembrane channels mediating the relevant [Ca2+]i transients remain incompletely understood. In the present study, the functional role of the microvascular endothelial site-specific α1G T-type Ca2+ channel in angiogenesis was examined. PMVECs intrinsically possess an in vitro angiogenic "network formation" capacity. Depleting extracellular Ca2+ abolishes network formation, whereas blockade of vascular endothelial growth factor receptor or nitric oxide synthase has little or no effect, suggesting that the network formation is a [Ca2+]i-dependent process. Blockade of the T-type Ca2+ channel or silencing of α1G, the only voltage-gated Ca2+ channel subtype expressed in PMVECs, disrupts network formation. In contrast, blockade of canonical transient receptor potential (TRP) isoform 4 or TRP vanilloid 4, two other Ca2+ permeable channels expressed in PMVECs, has no effect on network formation. T-type Ca2+ channel blockade also reduces proliferation, cell-matrix adhesion, and migration, three major components of angiogenesis in PMVECs. An in vivo study demonstrated that the mice lacking α1G exhibited a profoundly impaired postinjury cell proliferation in the lungs following lipopolysaccharide challenge. Mechanistically, T-type Ca2+ channel blockade reduces Akt phosphorylation in a dose-dependent manner. Blockade of Akt or its upstream activator, phosphatidylinositol-3-kinase (PI3K), also impairs network formation. Altogether, these findings suggest a novel functional role for the α1G T-type Ca2+ channel to promote the cell's angiogenic potential via a PI3K-Akt signaling pathway.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Células Endoteliais/metabolismo , Pulmão/metabolismo , Neovascularização Patológica/metabolismo , Animais , Cálcio/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Feminino , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Masculino , Camundongos , Fosfatidilinositol 3-Quinase/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Canais de Cátion TRPC/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
Am J Physiol Lung Cell Mol Physiol ; 316(4): L691-L700, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30758991

RESUMO

The second messenger, cAMP, is highly compartmentalized to facilitate signaling specificity. Extracellular vesicles (EVs) are submicron, intact vesicles released from many cell types that can act as biomarkers or be involved in cell-to-cell communication. Although it is well recognized that EVs encapsulate functional proteins and RNAs/miRNAs, currently it is unclear whether cyclic nucleotides are encapsulated within EVs to provide an additional second messenger compartment. Using ultracentrifugation, EVs were isolated from the culture medium of unstimulated systemic and pulmonary endothelial cells. EVs were also isolated from pulmonary microvascular endothelial cells (PMVECs) following stimulation of transmembrane adenylyl cyclase (AC) in the presence or absence of the phosphodiesterase 4 inhibitor rolipram over time. Whereas cAMP was detected in EVs isolated from endothelial cells derived from different vascular beds, it was highest in EVs isolated from PMVECs. Treatment of PMVECs with agents that increase near-membrane cAMP led to an increase in cAMP within corresponding EVs, yet there was no increase in EV number. Elevated cell cAMP, measured by whole cell measurements, peaked 15 min after treatment, yet in EVs the peak increase in cAMP was delayed until 60 min after cell stimulation. Cyclic AMP was also increased in EVs collected from the perfusate of isolated rat lungs stimulated with isoproterenol and rolipram, thus corroborating cell culture findings. When added to unperturbed confluent PMVECs, EVs containing elevated cAMP were not barrier disruptive like cytosolic cAMP but maintained monolayer resistance. In conclusion, PMVECs release EVs containing cAMP, providing an additional compartment to cAMP signaling.


Assuntos
Comunicação Celular , AMP Cíclico/metabolismo , Células Endoteliais/metabolismo , Vesículas Extracelulares/metabolismo , Pulmão/metabolismo , Sistemas do Segundo Mensageiro , Adenilil Ciclases/metabolismo , Animais , Células Endoteliais/citologia , Pulmão/citologia , Masculino , Ratos , Ratos Sprague-Dawley
13.
Breast Cancer Res Treat ; 174(3): 731-740, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30656459

RESUMO

PURPOSE: Palbociclib is approved in 1st line for hormone receptor (HR)-positive HER2-negative advanced breast cancer (ABC). A Compassionate Access Programme previously allowed patients to receive it in 4th line. However, Palbociclib has not been specifically tested in this population. We aimed to determine the safety and efficacy profile of Palbociclib within the Programme across ten institutions in the United Kingdom. METHODS: We retrospectively identified HR-positive HER2-negative ABC patients on the Programme between December 2015 and September 2017. Demographics, disease characteristics, prior treatments, blood tests, toxicities, treatment delays and responses were recorded. Simple statistics, Fisher's exact test, χ2 method and Cox regression were used. RESULTS: 118 patients identified had a median age of 59. 82.2% were postmenopausal and 92.4% performance status 0-1. 81.4% had visceral involvement and 6.8% bone-only disease after a median of 5 prior treatments and 3 prior chemotherapies. Clinical benefit rate was 47.5%, overall response rate 15.8%, median PFS 4.5 months and median OS 15.8 months. Longer progression-free survival on prior endocrine therapy was a predictor of longer PFS and OS. 89.7% developed neutropenia (grade ≥ 3 in 56.8%). 5.1% experienced febrile neutropenia. 48.3% had dose reductions and 3.4% discontinued Palbociclib following toxicity. No statistically significant difference in grade ≥ 3 neutropenia was observed according to metastatic sites nor previous treatments. CONCLUSIONS: This is the most extensive analysis of palbociclib in ≥ 4th-line setting. Clinical benefit was confirmed particularly for endocrine-sensitive, predominantly bony disease and in earlier lines of treatment. Safety was similar to PALOMA trials with higher febrile neutropenia rate.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Piperazinas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Piridinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Piperazinas/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Piridinas/efeitos adversos , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Reino Unido
14.
Ultrastruct Pathol ; 42(2): 193-197, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29466085

RESUMO

Acute renal failure in the setting of infection with human immunodeficiency virus can be due to various causes including pre-renal causes such as hypotension, sepsis, and nephrotoxic agents; thrombotic microangiopathy; or direct renal parenchymal infections by opportunistic organisms. We present a case of cryptococcal nephritis in a patient with systemic cryptococcosis and discuss the clinical findings as well as the histological, immunofluorescent, and transmission electron microscopy findings in the renal biopsy.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/patologia , Injúria Renal Aguda/microbiologia , Criptococose/imunologia , Infecções por HIV/complicações , Hospedeiro Imunocomprometido , Injúria Renal Aguda/imunologia , Injúria Renal Aguda/patologia , Adulto , Criptococose/patologia , Evolução Fatal , Humanos , Masculino , Microscopia Eletrônica de Transmissão
15.
Paediatr Child Health ; 22(5): 277-281, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29479234

RESUMO

PURPOSE: No studies have explored the experiences of Canadian mechanical ventilator-assisted adolescents (VAAs) living at home as they transition from paediatric to adult health providers. A better understanding of the needs of this growing population is essential to provide transition services responsive to VAAs and caregiver-identified needs. METHODS: We conducted semistructured telephone interviews with adolescents and family caregivers who had recently initiated or completed transition to adult care recruited from three Canadian university-affiliated paediatric home ventilation programs. We analyzed transcripts using a theoretical framework for understanding facilitators and barriers to transition. RESULTS: We interviewed 18 individuals representing 14 episodes of paediatric to adult transition. Participants identified early planning, written informational materials and joint paediatric-adult provider-family transition meetings as facilitators of care transition to adult services and providers. Barriers included insufficient information, limited access to interprofessional (nursing and allied health) providers and reduced funding or health services. Barriers resulted in service disruption and a sense of 'medical homelessness'. While most families related a positive transition to a new 'medical home', families caring for VAAs with moderate-to-severe cognitive and/or physical dependence more commonly reported transition difficulties. CONCLUSIONS: Important opportunities exist to enable improvements in the transition experiences of VAAs and their family caregivers. To maximize service continuity during paediatric to adult transition, future research should focus on transition navigator roles, interprofessional health outreach and the needs of families caring for VAAs with cognitive and physical deficits.

16.
Liver Int ; 36(12): 1821-1828, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27214151

RESUMO

BACKGROUND & AIMS: The Albumin-Bilirubin (ALBI) grade was proposed as an objective means to evaluate liver function in patients with Hepatocellular Carcinoma (HCC). ALBI grade 1 vs 2 were proposed as stratification factors within the Child Pugh (CP) A class. However, the original publication did not provide comparison with the subclassification by points (5-15) within the CP classification. METHODS: We retrospectively analysed data from patients treated with sorafenib for HCC from 17 centres in United Kingdom and France. Overall survival (OS) was analysed using the Kaplan-Meier method and a Cox regression model. Discriminatory abilities of the classifications were assessed with the log likelihood ratio, Harrell's C statistics and Akaike information criterion. RESULTS: Data from 1019 patients were collected, of which 905 could be assessed for both scores. 92% of ALBI grade 1 were CP A5 while ALBI 2 included a broad range of CP scores of which 44% were CP A6. Median OS was 10.2, 7.0 and 3.6 months for CP scores A5, A6 and >A6, respectively (P < 0.001), Hazard Ratio (HR) = 1.60 (95%CI: 1.35-1.89, P < 0.001) for A6 vs A5. Median OS was 10.9, 6.6 and 3.0 months for ALBI grade 1, 2 and 3, respectively (P < 0.001), HR = 1.68 (1.43-1.97, P < 0.001) for grade 2 vs 1. Discriminatory abilities of CP and ALBI were similar in the CP A population, but better for CP in the overall population. CONCLUSIONS: Our findings support the use CP class A as an inclusion criterion, and ALBI as a stratification factor in trials of systemic therapy.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Bilirrubina/análise , Feminino , França , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Niacinamida/uso terapêutico , Prognóstico , Estudos Retrospectivos , Albumina Sérica/análise , Sorafenibe , Análise de Sobrevida , Reino Unido , Adulto Jovem
17.
Arch Phys Med Rehabil ; 97(7): 1163-1181.e14, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26707409

RESUMO

OBJECTIVE: To create evidence-based guidelines evaluating foot care interventions for the management of juvenile idiopathic arthritis (JIA). DATA SOURCES: An electronic literature search of the following databases from database inception to May 2015 was conducted: MEDLINE (Ovid), EMBASE (Ovid), Cochrane CENTRAL, and clinicaltrials.gov. STUDY SELECTION: The Ottawa Panel selection criteria targeted studies that assessed foot care or foot orthotic interventions for the management of JIA in those aged 0 to ≤18 years. The Physiotherapy Evidence Database scale was used to evaluate study quality, of which only high-quality studies were included (score, ≥5). A total of 362 records were screened, resulting in 3 full-text articles and 1 additional citation containing supplementary information included for the analysis. DATA EXTRACTION: Two reviewers independently extracted study data (intervention, comparator, outcome, time period, study design) from the included studies by using standardized data extraction forms. Directed by Cochrane Collaboration methodology, the statistical analysis produced figures and graphs representing the strength of intervention outcomes and their corresponding grades (A, B, C+, C, C-, D+, D, D-). Clinical significance was achieved when an improvement of ≥30% between the intervention and control groups was present, whereas P>.05 indicated statistical significance. An expert panel Delphi consensus (≥80%) was required for the endorsement of recommendations. DATA SYNTHESIS: All included studies were of high quality and analyzed the effects of multidisciplinary foot care, customized foot orthotics, and shoe inserts for the management of JIA. Custom-made foot orthotics and prefabricated shoe inserts displayed the greatest improvement in pain intensity, activity limitation, foot pain, and disability reduction (grades A, C+). CONCLUSIONS: The use of customized foot orthotics and prefabricated shoe inserts seems to be a good choice for managing foot pain and function in JIA.


Assuntos
Artrite Juvenil/reabilitação , Órtoses do Pé , Manejo da Dor/métodos , Modalidades de Fisioterapia , Técnica Delphi , Prática Clínica Baseada em Evidências , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sapatos
18.
J Interprof Care ; 30(5): 599-605, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27340933

RESUMO

Within the care of people living with respiratory conditions, nursing, physiotherapy, and respiratory therapy healthcare professionals routinely work in interprofessional teams. To help students prepare for their future professional roles, there is a need for them to be involved in interprofessional education. The purpose of this project was to compare two different methods of patient simulation in improving interprofessional competencies for students in nursing, physiotherapy, and respiratory therapy programmes. The Canadian Interprofessional Health Collaborative competencies of communication, collaboration, conflict resolution patient/family-centred care, roles and responsibilities, and team functioning were measured. Using a quasi-experimental pre-post intervention approach two different interprofessional workshops were compared: the combination of standardised and simulated patients, and exclusively standardised patients. Students from nursing, physiotherapy, and respiratory therapy programmes worked together in these simulation-based activities to plan and implement care for a patient with a respiratory condition. Key results were that participants in both years improved in their self-reported interprofessional competencies as measured by the Interprofessional Collaborative Competencies Attainment Survey (ICCAS). Participants indicated that they found their interprofessional teams did well with communication and collaboration. But the participants felt they could have better involved the patients and their family members in the patient's care. Regardless of method of patient simulation used, mannequin or standardised patients, students found the experience beneficial and appreciated the opportunity to better understand the roles of other healthcare professionals in working together to help patients living with respiratory conditions.


Assuntos
Comportamento Cooperativo , Relações Interprofissionais , Simulação de Paciente , Especialidade de Fisioterapia , Competência Profissional , Terapia Respiratória , Humanos , Capacitação em Serviço , Masculino , Doença Pulmonar Obstrutiva Crônica/terapia
19.
Future Oncol ; 10(9): 1559-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25145427

RESUMO

Approximately 50% of patients with cutaneous metastatic melanoma harbor a somatic BRAF mutation. BRAF inhibitors are now established in the treatment paradigm of BRAF mutant melanoma, following the approval of vemurafenib by the US FDA in 2011. The vast majority of patients obtain some degree of tumor shrinkage with oral BRAF inhibitors, and responses are often rapid. However, resistance inevitably develops, with a median progression-free survival of 5-7 months. The oral MEK inhibitor trametinib has also shown activity in BRAF mutant melanoma in Phase III trials. We review the rationale for treating BRAF mutant melanoma with trametinib, as single-agent therapy and in combination with BRAF inhibitors, as well as the clinical data to date.


Assuntos
Antineoplásicos/uso terapêutico , Melanoma/tratamento farmacológico , Piridonas/uso terapêutico , Pirimidinonas/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Antineoplásicos/farmacologia , Ensaios Clínicos como Assunto , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , MAP Quinase Quinase Quinases/antagonistas & inibidores , Melanoma/genética , Melanoma/mortalidade , Melanoma/secundário , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Piridonas/farmacologia , Pirimidinonas/farmacologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia
20.
BMC Clin Pathol ; 14(1): 46, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25580091

RESUMO

BACKGROUND: At the time of the study, the HIV-treatment policy in South Africa included highly active antiretroviral therapy (HAART) regimens 1 (nucleotide reverse transcriptase inhibitors (NRTIs) only), and 2 (protease inhibitors (PI) and NRTIs). HAART is associated with the lipodystrophy syndrome, insulin resistance and reduced total adiponectin (TA) levels. The high molecular weight (HMW):TA ratio is a superior marker of insulin resistance. The aim of this study was to establish whether HMW:TA ratios are low in patients on PIs and whether they correlate with insulin resistance. METHODS: This was a cross-sectional study undertaken in an antiretroviral clinic at a tertiary hospital. The participants were 66 HIV-infected females: 22 were on regimen 2 (PI group), 22 on regimen 1 (non-PI) and 22 treatment naïve (TN), matched for BMI and age. Patients with a history of diabetes or impaired glucose tolerance were excluded. Serum adiponectin multimers were analysed using the AlpcoTM Adiponectin (Multimeric) enzyme immunoassay. Waist hip ratios (WHR), glucose and insulin levels were assessed, and HOMA-IR and QUICKI calculated. Data were analysed non-parametrically and multivariate analysis was performed. RESULTS: TA and HMW levels were lower in the treatment groups than in the TN group. HMW:TA was lower in the PI than in the non-PI and TN groups, and in the non-PI than in the TN groups. HMW:TA correlated negatively with waist, insulin and HOMA-IR, independently of BMI and duration of therapy. HOMA-IR and QUICKI did not differ among the groups. CONCLUSION: HMW:TA is significantly decreased with HAART (particularly with PIs, but also with non-PIs) and may be a more sensitive marker of insulin resistance in these patients than conventional markers or HMW and total adiponectin individually.

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