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1.
Proc Natl Acad Sci U S A ; 119(38): e2209514119, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36048924

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cell entry starts with membrane attachment and ends with spike (S) protein-catalyzed membrane fusion depending on two cleavage steps, namely, one usually by furin in producing cells and the second by TMPRSS2 on target cells. Endosomal cathepsins can carry out both. Using real-time three-dimensional single-virion tracking, we show that fusion and genome penetration require virion exposure to an acidic milieu of pH 6.2 to 6.8, even when furin and TMPRSS2 cleavages have occurred. We detect the sequential steps of S1-fragment dissociation, fusion, and content release from the cell surface in TMPRRS2-overexpressing cells only when exposed to acidic pH. We define a key role of an acidic environment for successful infection, found in endosomal compartments and at the surface of TMPRSS2-expressing cells in the acidic milieu of the nasal cavity.


Assuntos
COVID-19 , Cavidade Nasal , SARS-CoV-2 , Serina Endopeptidases , Internalização do Vírus , COVID-19/virologia , Furina/genética , Furina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Cavidade Nasal/química , Cavidade Nasal/virologia , SARS-CoV-2/fisiologia , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(40): e2210990119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36122200

RESUMO

Variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) challenge currently available coronavirus disease 2019 vaccines and monoclonal antibody therapies through epitope change on the receptor binding domain of the viral spike glycoprotein. Hence, there is a specific urgent need for alternative antivirals that target processes less likely to be affected by mutation, such as the membrane fusion step of viral entry into the host cell. One such antiviral class includes peptide inhibitors, which block formation of the so-called heptad repeat 1 and 2 (HR1HR2) six-helix bundle of the SARS-CoV-2 spike (S) protein and thus interfere with viral membrane fusion. We performed structural studies of the HR1HR2 bundle, revealing an extended, well-folded N-terminal region of HR2 that interacts with the HR1 triple helix. Based on this structure, we designed an extended HR2 peptide that achieves single-digit nanomolar inhibition of SARS-CoV-2 in cell-based and virus-based assays without the need for modifications such as lipidation or chemical stapling. The peptide also strongly inhibits all major SARS-CoV-2 variants to date. This extended peptide is ∼100-fold more potent than all previously published short, unmodified HR2 peptides, and it has a very long inhibition lifetime after washout in virus infection assays, suggesting that it targets a prehairpin intermediate of the SARS-CoV-2 S protein. Together, these results suggest that regions outside the HR2 helical region may offer new opportunities for potent peptide-derived therapeutics for SARS-CoV-2 and its variants, and even more distantly related viruses, and provide further support for the prehairpin intermediate of the S protein.


Assuntos
Tratamento Farmacológico da COVID-19 , Glicoproteína da Espícula de Coronavírus , Antivirais/química , Antivirais/farmacologia , Humanos , Peptídeos/química , Peptídeos/farmacologia , SARS-CoV-2/efeitos dos fármacos
3.
Clin Anat ; 33(7): 1014-1018, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31769105

RESUMO

Over the past 10 years, metacarpal fractures have had an annual incidence of 13.6 per 10,000 individuals. Literature has not reviewed anatomical variations through radiographic imaging, which may play a role in reducing postoperative complications. The purpose of this study was to use radiographic imaging to provide a detailed anatomy of the second through fifth metacarpals. This retrospective study measured length, neck width, narrowest body width, and narrowest medullary canal width of the second through fifth metacarpals through the use of posteroanterior X-rays. Patients who were ≥18 years and received hand radiographs from January 2015 to July 2019 were included in this study. Those with acute injury or fracture of the metacarpal were excluded. Five hundred and seventy-two metacarpals were included in this study, with 143 metacarpals measured each for the second through fifth metacarpal. The second metacarpal had the largest measured length, neck width, and narrowest body width at 68.72, 12.34, and 8.74 mm, respectively. The fifth metacarpal had the greatest average medullary canal width at 4.15 mm. This is the largest study in literature to comprehensively examine the anatomical variation of the second through fifth metacarpals. The second metacarpal had greatest dimensions except for canal width, which was the fifth metacarpal. Men almost consistently had greater metacarpal size when compared to women, and age was associated with second and third metacarpal canal width. The increased knowledge of metacarpal anatomy may potentially lay the foundation of further improvement of metacarpal implants and potentially reduce postoperative complications. Clin. Anat., 33:1014-1018, 2020. © 2019 Wiley Periodicals, Inc.


Assuntos
Ossos Metacarpais/anatomia & histologia , Ossos Metacarpais/diagnóstico por imagem , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Fatores Sexuais
4.
J Surg Oncol ; 117(6): 1137-1143, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29205352

RESUMO

BACKGROUND AND OBJECTIVES: Pure tubular carcinomas (TC) of the breast are generally considered to have an excellent prognosis. This study aimed to analyze the characteristics and survival of patients with TC. METHODS: This was a retrospective study conducted at the CHU de Québec-Université Laval. Databases were searched for all cases treated between April 1997 and December 2010. Survival was retrieved from the Province of Quebec Ministry of Health. Follow-up was censored on December 31, 2011. Overall survival (OS) was compared to patients with invasive ductal carcinoma (ICD) matched for age, tumor size, lymph node involvement, year of diagnosis, ER, PgR, and HER2, histological grade, lymphovascular invasion, and chemotherapy. RESULTS: The frequency of TC was 2.9% (n = 223/7563). Tumors size was 7.4 ± 8.8 mm, without lymphovascular invasion (95.1%), ER-positive (98.2%), PgR-positive (69.5%), and HER2-negative (100%). Patients were followed up for 7.1 ± 2.7 years. The actuarial 13-year OS was 89.0% for TC, compared to 85.8% for IDC (P = 0.13). For TC, the 13-year OS was 95.8% in NO patients compared to 90.0% for N1-3 (P = 0.01). CONCLUSION: Despite the general popular belief that patients with TC fare better than patients with IDC, the 13-year OS of TC was similar to that of grade I IDC.


Assuntos
Adenocarcinoma/mortalidade , Neoplasias da Mama/mortalidade , Carcinoma Ductal de Mama/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Feminino , Seguimentos , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos , Taxa de Sobrevida
5.
J Virol ; 90(8): 4160-4173, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26865712

RESUMO

UNLABELLED: Cassava mosaic begomoviruses (CMBs) cause cassava mosaic disease (CMD) across Africa and the Indian subcontinent. Like all members of the geminivirus family, CMBs have small, circular single-stranded DNA genomes. We report here the discovery of two novel DNA sequences, designated SEGS-1 and SEGS-2 (forsequencesenhancinggeminivirussymptoms), that enhance symptoms and break resistance to CMD. The SEGS are characterized by GC-rich regions and the absence of long open reading frames. Both SEGS enhanced CMD symptoms in cassava (Manihot esculentaCrantz) when coinoculated withAfrican cassava mosaic virus(ACMV),East African cassava mosaic Cameroon virus(EACMCV), orEast African cassava mosaic virus-Uganda(EACMV-UG). SEGS-1 also overcame resistance of a cassava landrace carrying the CMD2 resistance locus when coinoculated with EACMV-UG. Episomal forms of both SEGS were detected in CMB-infected cassava but not in healthy cassava. SEGS-2 episomes were also found in virions and whiteflies. SEGS-1 has no homology to geminiviruses or their associated satellites, but the cassava genome contains a sequence that is 99% identical to full-length SEGS-1. The cassava genome also includes three sequences with 84 to 89% identity to SEGS-2 that together encompass all of SEGS-2 except for a 52-bp region, which includes the episomal junction and a 26-bp sequence related to alphasatellite replication origins. These results suggest that SEGS-1 is derived from the cassava genome and facilitates CMB infection as an integrated copy and/or an episome, while SEGS-2 was originally from the cassava genome but now is encapsidated into virions and transmitted as an episome by whiteflies. IMPORTANCE: Cassava is a major crop in the developing world, with its production in Africa being second only to maize. CMD is one of the most important diseases of cassava and a serious constraint to production across Africa. CMD2 is a major CMD resistance locus that has been deployed in many cassava cultivars through large-scale breeding programs. In recent years, severe, atypical CMD symptoms have been observed occasionally on resistant cultivars, some of which carry the CMD2 locus, in African fields. In this report, we identified and characterized two DNA sequences, SEGS-1 and SEGS-2, which produce similar symptoms when coinoculated with cassava mosaic begomoviruses onto a susceptible cultivar or a CMD2-resistant landrace. The ability of SEGS-1 to overcome CMD2 resistance and the transmission of SEGS-2 by whiteflies has major implications for the long-term durability of CMD2 resistance and underscore the need for alternative sources of resistance in cassava.


Assuntos
Begomovirus/genética , DNA Viral , Manihot/virologia , Doenças das Plantas/virologia , Sequência de Bases , Begomovirus/patogenicidade , Clonagem Molecular , Genoma Viral , Vírus do Mosaico/genética , Vírus do Mosaico/patogenicidade , Doenças das Plantas/imunologia , Plasmídeos/genética , Tanzânia , Nicotiana
6.
Ann Pharmacother ; 48(4): 447-55, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24321851

RESUMO

BACKGROUND: Generic formulations are not necessarily identical to the original in terms of efficacy and adverse events. Generic docetaxel has been available in Canada since 2011. OBJECTIVE: To compare the occurrence of grade III to IV adverse events between original docetaxel and a generic formulation in breast cancer patients. METHODS: A consecutive series of 400 patients were assessed retrospectively: 200 who received the original docetaxel and 200 who received a generic formulation. Patients who received both formulations or received their chemotherapy outside our center were excluded. The primary outcome was the occurrence of grade III to IV adverse events related to docetaxel (febrile neutropenia, hand and foot syndrome, intestinal perforation, thrombotic event, and death). RESULTS: Three hundred-sixty-four patients were available for analysis (182/group). The use of a granulocyte colony-stimulating factor (G-CSF) was more frequent in the generic group (44.5% vs 28.8%), as well as treatment discontinuation (26.4% vs 14.8%). The occurrence of grade III to IV febrile neutropenia, hand and foot syndrome, intestinal perforation, thrombotic event, and docetaxel-related deaths were similar between the 2 formulations. However, grade IV febrile neutropenia was more frequent with the generic formulation (78.8% vs 56.3%). Limitations were the retrospective nature of the study and the variety of chemotherapy regimens. CONCLUSION: Adverse events occurrence was similar between the 2 formulations. However, febrile neutropenia was more serious with generic docetaxel, despite increased G-CSF use. Results suggest that the studied generic formulation may be safe, but more caution during treatments might be warranted, especially concerning febrile neutropenia events.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Medicamentos Genéricos/efeitos adversos , Taxoides/efeitos adversos , Idoso , Anedotas como Assunto , Neutropenia Febril Induzida por Quimioterapia/tratamento farmacológico , Neutropenia Febril Induzida por Quimioterapia/etiologia , Docetaxel , Feminino , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Mol Biol Cell ; 35(3): ar12, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117594

RESUMO

Insulin secretion depends on the Ca2+-regulated fusion of granules with the plasma membrane. A recent model of Ca2+-triggered exocytosis in secretory cells proposes that lipids in the plasma membrane couple the calcium sensor Syt1 to the membrane fusion machinery (Kiessling et al., 2018). Specifically, Ca2+-mediated binding of Syt1's C2 domains to the cell membrane shifts the membrane-anchored SNARE syntaxin-1a to a more fusogenic conformation, straightening its juxtamembrane linker. To test this model in live cells and extend it to insulin secretion, we enriched INS1 cells with a panel of lipids with different acyl chain compositions. Fluorescence lifetime measurements demonstrate that cells with more disordered membranes show an increase in fusion efficiency, and vice versa. Experiments with granules purified from INS1 cells and recombinant SNARE proteins reconstituted in supported membranes confirmed that lipid acyl chain composition determines SNARE conformation and that lipid disordering correlates with increased fusion. Addition of Syt1's C2AB domains significantly decreased lipid order in target membranes and increased SNARE-mediated fusion probability. Strikingly, Syt's action on both fusion and lipid order could be partially bypassed by artificially increasing unsaturated phosphatidylserines in the target membrane. Thus, plasma membrane lipids actively participate in coupling Ca2+/synaptotagmin-sensing to the SNARE fusion machinery in cells.


Assuntos
Células Secretoras de Insulina , Fusão de Membrana , Lipídeos de Membrana/metabolismo , Proteínas SNARE/metabolismo , Células Secretoras de Insulina/metabolismo , Membrana Celular/metabolismo , Sinaptotagmina I/química , Sinaptotagmina I/metabolismo , Exocitose , Proteínas Recombinantes/metabolismo , Cálcio/metabolismo
8.
J Gen Physiol ; 156(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37943249

RESUMO

TRPM7, a TRP channel with ion conductance and kinase activities, has emerged as an attractive drug target for immunomodulation. Reverse genetics and cell biological studies have already established a key role for TRPM7 in the inflammatory activation of macrophages. Advancing TRPM7 as a viable molecular target for immunomodulation requires selective TRPM7 inhibitors with in vivo tolerability and efficacy. Such inhibitors have the potential to interdict inflammatory cascades mediated by systemic and tissue-specialized macrophages. FTY720, an FDA-approved drug for multiple sclerosis inhibits TRPM7. However, FTY720 is a prodrug and its metabolite, FTY720-phosphate, is a potent agonist of sphingosine-1-phosphate (S1P) receptors. In this study, we test non-phosphorylatable FTY720 analogs, which are inert against S1PRs and well tolerated in vivo, for activity against TRPM7 and tissue bioavailability. Using patch clamp electrophysiology, we show that VPC01091.4 and AAL-149 block TRPM7 current at low micromolar concentrations. In culture, they act directly on macrophages to blunt LPS-induced inflammatory cytokine expression, though this likely occurrs through multiple molecular targets. We found that VPC01091.4 has significant and rapid accumulation in the brain and lungs, along with direct anti-inflammatory action on alveolar macrophages and microglia. Finally, using a mouse model of endotoxemia, we show VPC01091.4 to be an efficacious anti-inflammatory agent that arrests systemic inflammation in vivo. Together, these findings identify novel small molecule inhibitors that allow TRPM7 channel inhibition independent of S1P receptor targeting which demonstrate potent, polymodal anti-inflammatory activities ex vivo and in vivo.


Assuntos
Cloridrato de Fingolimode , Canais de Cátion TRPM , Cloridrato de Fingolimode/farmacologia , Ciclopentanos , Fosforilação
10.
Support Care Cancer ; 21(7): 1911-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23417563

RESUMO

PURPOSE: Building upon the findings of a recent qualitative investigation of women's experiences with rehabilitative vaginal dilator use, the primary goal of this article is to outline a set of preliminary clinical care recommendations that health care professionals may draw upon in addressing women's unique experiences with vaginal dilator use including their multifaceted struggles with the procedure, possibly enhancing adherence to this practice. METHODS: Ten women participated in in-depth interviews regarding their experiences with using the dilator as prescribed by their health care providers. Following the analysis of these interviews, members of the interdisciplinary research team met to review and discuss the development of clinical care recommendations stemming from these findings. RESULTS: Eight care recommendations aimed at addressing the concerns expressed by the women interviewed and at improving women's overall experiences with rehabilitative dilator use emerged: (1) introduce the dilator in a light and straightforward manner; (2) enhance dilator accessibility; (3) introduce the vaginal dilator early on in treatment; (4) emphasize health maintenance over intercourse as a benefit of dilator use; (5) explore and acknowledge women's values and views of sexuality; (6) increase awareness and sensitivity to emotional reactions; (7) enhance psychoeducational resources for supporting vaginal dilator use; and (8) ensure consistent institutional practice when introducing the dilator. CONCLUSION: The clinical care recommendations proposed here reflect the various challenges women may encounter when using the vaginal dilator--which vary from practical to, for some, profoundly emotional--and are designed to better position health care providers to help women navigate these challenges.


Assuntos
Dilatação/instrumentação , Neoplasias do Colo do Útero/fisiopatologia , Neoplasias do Colo do Útero/reabilitação , Vagina/fisiopatologia , Dilatação/normas , Feminino , Humanos , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto
11.
Polymers (Basel) ; 16(1)2023 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-38201730

RESUMO

Proteins are biomolecules with potential applications in agriculture, food sciences, pharmaceutics, biotechnology, and drug delivery. Interactions of hydrophilic and biocompatible polymers with proteins may impart proteolytic stability, improving the therapeutic effects of biomolecules and also acting as excipients for the prolonged storage of proteins under harsh conditions. The interactions of hydrophilic and stealth polymers such as poly(ethylene glycol), poly(trehalose), and zwitterionic polymers with various proteins are well studied. This study evaluates the molecular interactions of hydrophilic and optically active poly(vitamin B5 analogous methacrylamide) (poly(B5AMA)) with model proteins by fluorescence spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and circular dichroism (CD) spectroscopy analysis. The optically active hydrophilic polymers prepared using chiral monomers of R-(+)- and S-(-)-B5AMA by the photo-iniferter reversible addition fragmentation chain transfer (RAFT) polymerization showed concentration-dependent weak interactions of the polymers with bovine serum albumin and lysozyme proteins. Poly(B5AMA) also exhibited a concentration-dependent protein stabilizing effect at elevated temperatures, and no effect of the stereoisomers of polymers on protein thermal stability was observed. NMR analysis, however, showed poly(B5AMA) stereoisomer-dependent changes in the secondary structure of proteins.

12.
Curr Oncol ; 30(2): 2061-2072, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36826121

RESUMO

Our primary objective was to determine the proportion of trials that report the number of patients assessed for eligibility before randomization. We performed the systematic retrieval and analysis of all phase II, III, and IV RCTs published between 2013 and 2015 in four high-impact-factor journals in the field of clinical oncology. Among 456 RCTs reviewed, 236 trials (51.8%) reported the number of patients assessed for eligibility. Among the 236 trials that reported the entire enrollment process, the reasons for patient exclusion could be found in 184 trials (78%). A flow diagram was presented in 452 trials (99.1%), and 98 trials (21.5%) included a discussion on generalizability. Reporting the parameters of external validity in medical oncology RCTs is challenging. Improving adherence to the 2010 CONSORT guidelines concerning the enrollment process could help clinicians and health policymakers establish to whom trial results apply.


Assuntos
Publicações Periódicas como Assunto , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Oncologia
13.
Orthopedics ; 46(2): 121-127, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36476241

RESUMO

Formal patient complaints and malpractice events involving orthopedic trauma surgeons (OTSs) can have substantial career implications. Our purpose was to analyze formal patient complaints, risk events, and malpractice events against OTSs during a 10-year period. We reviewed all formal patient complaints within our institution's patient advocacy database involving 9 fellowship-trained OTSs throughout a decade. Complaints were categorized using the Patient Complaint Analysis System. Potential risk and malpractice events involving the OTSs were recorded. A control group of all patients seen by the surgeons during the study period was created. Demographics between patients with complaints and the control group were analyzed, as were malpractice, risk, and complaint rates between the surgeons. Of 33,770 patients, 136 filed a formal complaint (0.40%). There were 29 malpractice claims and 2 malpractice lawsuits. The care and treatment domain accounted for the highest percentage of complaints (36%), followed by the access and availability domain (26%). Results of the logistic regression analysis indicated that private insurance (odds ratio, 1.58) and operative treatment (odds ratio, 3.65) were significantly associated with complaints. Despite statistically significant differences in the rates of complaint and risk events between surgeons, malpractice events did not differ. The rate of patient complaints within a large orthopedic trauma practice during a 10-year period was 0.40%. Patients with private insurance and those treated operatively were more likely to file a complaint. Whereas complaint rates among surgeons varied, there was no significant difference in the rate of malpractice events. Understanding patient complaint rates and categorizations may allow surgeons to target areas for improvement. [Orthopedics. 2023;46(2):121-127.].


Assuntos
Imperícia , Procedimentos Ortopédicos , Cirurgiões Ortopédicos , Cirurgiões , Humanos , Estudos Retrospectivos , Procedimentos Ortopédicos/efeitos adversos
14.
Clin Lymphoma Myeloma Leuk ; 23(3): 203-210, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36646606

RESUMO

BACKGROUND: Chimeric antigen receptor (CAR) T-cells are an important new third-line treatment option for large B-cell lymphoma (LBCL). The objective response rates in pivotal early phase clinical trials with CAR T-cells were very promising. The objective of this study was to describe the efficacy results obtained with CAR T-cells infusions in our institution and to compare the toxicities of our cohort with those of pivotal trials and studies conducted in a real-life setting. PATIENTS AND METHODS: Efficacy and safety data were retrospectively collected from 25 patients with LBCL treated with CAR T-cells therapy at CHU de Québec-Université Laval. A literature search was then performed to identify other efficacy or safety data from a real-life setting. RESULTS: At 3 months post infusion, the objective response rate (ORR) in our population with tisagenlecleucel and axicabtagene-ciloleucel were 20% and 47%, respectively. Bulky disease was the only negative predictor of poor response at 3 months (0% vs. 53%, P = .03). Bulky disease was associated with a median PFS of 2 months compared to 5 months for non-bulky disease (P = .0009). Grade ≥ 3 hematological toxicities were greater in patients treated with axi-cel (60% vs. 20%, P = .048), without bone marrow involvement (55% vs. 0%, P =.046), without stage IV disease (72% vs. 21%, P =.02), with refractory disease (67% vs. 10%, P =.01) or having been affected by cytokine release syndrome (58% vs. 0%, P =.02). CONCLUSION: The poor response rate at 3 months after infusion in our cohort was influenced mainly by bulky disease. Further studies are needed to better characterize the loss of efficacy of CAR T-cells because the majority of patients will relapse over time.


Assuntos
Linfoma Difuso de Grandes Células B , Recidiva Local de Neoplasia , Humanos , Estudos Retrospectivos , Canadá , Recidiva Local de Neoplasia/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Imunoterapia Adotiva/métodos , Linfócitos T , Antígenos CD19
15.
bioRxiv ; 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37662207

RESUMO

TRPM7, a TRP channel with ion conductance and kinase activities, has emerged as an attractive drug target for immunomodulation. Reverse genetics and cell biological studies have already established a key role for TRPM7 in the inflammatory activation of macrophages. Advancing TRPM7 as a viable molecular target for immunomodulation requires selective TRPM7 inhibitors with in vivo tolerability and efficacy. Such inhibitors have the potential to interdict inflammatory cascades mediated by systemic and tissue-specialized macrophages. FTY720, an FDA-approved drug for multiple sclerosis inhibits TRPM7. However, FTY720 is a prodrug and its metabolite, FTY720-phosphate, is a potent agonist of sphingosine 1-phosphate (S1P) receptors. In this study, we tested non-phosphorylatable FTY720 analogs, which are inert against S1PRs and well tolerated in vivo , for activity against TRPM7 and tissue bioavailability. Using patch clamp electrophysiology, we show that VPC01091.4 and AAL-149 block TRPM7 current at low micromolar concentrations. In culture, they act directly on macrophages to blunt LPS-induced inflammatory cytokine expression, an effect that is predominantly but not solely mediated by TRPM7. We found that VPC01091.4 has significant and rapid accumulation in the brain and lungs, along with direct anti-inflammatory action on alveolar macrophages and microglia. Finally, using a mouse model of endotoxemia, we show VPC01091.4 to be an efficacious anti-inflammatory agent that arrests systemic inflammation in vivo . Together, these findings identify novel small molecule inhibitors that allow TRPM7 channel inhibition independent of S1P receptor targeting. These inhibitors exhibit potent anti-inflammatory properties that are mediated by TRPM7 and likely other molecular targets that remain to be identified.

16.
J Sex Med ; 9(4): 1162-73, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22304701

RESUMO

INTRODUCTION: Regular use of vaginal dilators has been recommended as a prophylactic measure following radiation treatment for gynecological cancers in order to minimize vaginal stenosis and promote optimal healing of the vagina. Despite the well-established reluctance of women to adopt this practice, little is known about the difficulties and concerns associated with vaginal dilator use. AIM: To investigate women's experiences with the vaginal dilator and to understand the psychosocial factors that influence women's adoption of rehabilitative dilator use. METHODS: This is an exploratory qualitative study using semi-structured interviews with a sample of 10 women with a history of gynecological cancer and who were prescribed a vaginal dilator. Interviews were analyzed using the grounded theory method and examined for recurrent themes. MAIN OUTCOME MEASURE: The main outcome measure was a semi-structured interview comprised of open-ended questions designed to elicit information concerning topic areas relevant to gynecological cancer, vaginal dilator use, and sexuality. RESULTS: The analysis resulted in five main categories underlying the core category of "From 'sex toy' to intrusive imposition." These were: (i) embarrassing sex toy; (ii) reliving the invasion of treatment; (iii) aversive "hands-on" experience; (iv) not at the forefront of my recovery; and (v) minimizing the resistance. CONCLUSIONS: Rehabilitative vaginal dilator use is a complex, multifaceted, and personal phenomenon that carries deep psychological and emotional implications that make it intrusive. These findings may enhance the way in which vaginal dilators are introduced and help healthcare providers address better women's difficulties and concerns with the dilators. Ultimately, it may also lead to improved health maintenance and quality of life for women recovering from gynecological cancer.


Assuntos
Dilatação/instrumentação , Dilatação/psicologia , Neoplasias do Endométrio/radioterapia , Cooperação do Paciente/psicologia , Lesões por Radiação/reabilitação , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia , Vagina/efeitos da radiação , Adaptação Psicológica , Adulto , Idoso , Atitude Frente a Saúde , Braquiterapia , Quimiorradioterapia Adjuvante , Constrição Patológica/reabilitação , Mecanismos de Defesa , Neoplasias do Endométrio/tratamento farmacológico , Feminino , Humanos , Entrevista Psicológica , Pessoa de Meia-Idade , Dor/psicologia
17.
Clin Trials ; 9(5): 652-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23060323

RESUMO

BACKGROUND: Clinical trial recruitment can be impeded by eligibility criteria being too numerous or too restrictive. PURPOSE: This study's principal objective was to determine whether a specific category of eligibility criteria could be identified as a major barrier to patient enrollment. METHODS: Nine phase II or III clinical trials, opened between June 2004 and July 2008, were selected. A retrospective cohort of women diagnosed with invasive, nonmetastatic breast cancer and potentially eligible for these clinical trials was used. All eligibility criteria were sorted into the following categories: definition of disease, precision, safety, ethical and legal, or administrative. A total of 985 patient-trials were evaluated, defined as the experimental unit since one patient could be eligible to more than one trial. Proportions of cases with 'not met' eligibility criteria were assessed for each category in each trial. RESULTS: Two clinical trials had a 'not met' subcategory criterion of over 20%. 'Pathology' and 'consent' subcategory criteria were 'not met' in 24.2% and 92.7% of cases for the NEOCAN and NCIC CTG MA.27 trials, respectively. NCIC CTG MA.27 had the highest proportion of 'not met' subcategory due to an inclusion criterion requiring participation to two companion studies. National Surgical Adjuvant Breast and Bowel Project (NSABP) B-38 had a proportion of 18.8% of cases 'not meeting' the receptor status subcategory criterion. All other subcategories of eligibility criteria assessed were 'not met' by less than 15% of patients. Overall, few subcategories had over 10% of ineligible patients. LIMITATIONS: Many eligibility criteria were considered 'nonevaluable' because the information evaluated would have required additional procedures not performed as part of the general practice. CONCLUSION: The subjects from the study population are not precluded from entry in a trial because of stringent eligibility criteria. Eligibility criteria should reflect as much as possible the whole population to whom the treatment will be offered, with the exception of drugs targeting a specific receptor or pathway where only a subpopulation is hypothesized to benefit from the therapy. In the breast cancer clinical trials evaluated for the present study, no criterion precluding recruitment was shared by many or all trials and no specific eligibility criterion was consistently the reason for patients' ineligibility.


Assuntos
Neoplasias da Mama/terapia , Ensaios Clínicos Fase II como Assunto/métodos , Ensaios Clínicos Fase III como Assunto/métodos , Terapia Neoadjuvante/métodos , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Fatores Etários , Feminino , Humanos , Estadiamento de Neoplasias , Estudos Retrospectivos
18.
J Int Acad Periodontol ; 14(2): 42-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22799128

RESUMO

Stress has long been considered to be a major contributor to the clinical manifestation of many diseases. In this review the role that stress might play in chronic periodontitis is considered. Sufficient evidence is available to support the notion that stress could be a contributing factor in periodontal destruction in the presence of periodontal pathogens in a susceptible individual.


Assuntos
Periodontite Crônica/fisiopatologia , Estresse Fisiológico/fisiologia , Periodontite Crônica/imunologia , Periodontite Crônica/psicologia , Humanos , Infecções , Estresse Fisiológico/imunologia , Estresse Psicológico/imunologia , Estresse Psicológico/fisiopatologia , Cicatrização/fisiologia
19.
Rev Neurosci ; 33(4): 439-465, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-34534428

RESUMO

The present review assesses the potential neural impact of impoverished, captive environments on large-brained mammals, with a focus on elephants and cetaceans. These species share several characteristics, including being large, wide-ranging, long-lived, cognitively sophisticated, highly social, and large-brained mammals. Although the impact of the captive environment on physical and behavioral health has been well-documented, relatively little attention has been paid to the brain itself. Here, we explore the potential neural consequences of living in captive environments, with a focus on three levels: (1) The effects of environmental impoverishment/enrichment on the brain, emphasizing the negative neural consequences of the captive/impoverished environment; (2) the neural consequences of stress on the brain, with an emphasis on corticolimbic structures; and (3) the neural underpinnings of stereotypies, often observed in captive animals, underscoring dysregulation of the basal ganglia and associated circuitry. To this end, we provide a substantive hypothesis about the negative impact of captivity on the brains of large mammals (e.g., cetaceans and elephants) and how these neural consequences are related to documented evidence for compromised physical and psychological well-being.


Assuntos
Elefantes , Animais , Atenção , Encéfalo/fisiologia , Elefantes/fisiologia , Elefantes/psicologia , Humanos
20.
Nat Commun ; 13(1): 3230, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680919

RESUMO

Efficient clearance of apoptotic cells by phagocytosis, also known as efferocytosis, is fundamental to developmental biology, organ physiology, and immunology. Macrophages use multiple mechanisms to detect and engulf apoptotic cells, but the signaling pathways that regulate the digestion of the apoptotic cell cargo, such as the dynamic Ca2+ signals, are poorly understood. Using an siRNA screen, we identify TRPM7 as a Ca2+-conducting ion channel essential for phagosome maturation during efferocytosis. Trpm7-targeted macrophages fail to fully acidify or digest their phagosomal cargo in the absence of TRPM7. Through perforated patch electrophysiology, we demonstrate that TRPM7 mediates a pH-activated cationic current necessary to sustain phagosomal acidification. Using mice expressing a genetically-encoded Ca2+ sensor, we observe that phagosome maturation requires peri-phagosomal Ca2+-signals dependent on TRPM7. Overall, we reveal TRPM7 as a central regulator of phagosome maturation during macrophage efferocytosis.


Assuntos
Sinalização do Cálcio , Fagocitose , Canais de Cátion TRPM , Animais , Macrófagos/metabolismo , Camundongos , Fagocitose/fisiologia , Fagossomos/metabolismo , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo
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