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1.
N Engl J Med ; 390(15): 1359-1371, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38631003

RESUMO

BACKGROUND: Adjuvant pembrolizumab therapy after surgery for renal-cell carcinoma was approved on the basis of a significant improvement in disease-free survival in the KEYNOTE-564 trial. Whether the results regarding overall survival from the third prespecified interim analysis of the trial would also favor pembrolizumab was uncertain. METHODS: In this phase 3, double-blind, placebo-controlled trial, we randomly assigned (in a 1:1 ratio) participants with clear-cell renal-cell carcinoma who had an increased risk of recurrence after surgery to receive pembrolizumab (at a dose of 200 mg) or placebo every 3 weeks for up to 17 cycles (approximately 1 year) or until recurrence, the occurrence of unacceptable toxic effects, or withdrawal of consent. A significant improvement in disease-free survival according to investigator assessment (the primary end point) was shown previously. Overall survival was the key secondary end point. Safety was a secondary end point. RESULTS: A total of 496 participants were assigned to receive pembrolizumab and 498 to receive placebo. As of September 15, 2023, the median follow-up was 57.2 months. The disease-free survival benefit was consistent with that in previous analyses (hazard ratio for recurrence or death, 0.72; 95% confidence interval [CI], 0.59 to 0.87). A significant improvement in overall survival was observed with pembrolizumab as compared with placebo (hazard ratio for death, 0.62; 95% CI, 0.44 to 0.87; P = 0.005). The estimated overall survival at 48 months was 91.2% in the pembrolizumab group, as compared with 86.0% in the placebo group; the benefit was consistent across key subgroups. Pembrolizumab was associated with a higher incidence of serious adverse events of any cause (20.7%, vs. 11.5% with placebo) and of grade 3 or 4 adverse events related to pembrolizumab or placebo (18.6% vs. 1.2%). No deaths were attributed to pembrolizumab therapy. CONCLUSIONS: Adjuvant pembrolizumab was associated with a significant and clinically meaningful improvement in overall survival, as compared with placebo, among participants with clear-cell renal-cell carcinoma at increased risk for recurrence after surgery. (Funded by Merck Sharp and Dohme, a subsidiary of Merck; KEYNOTE-564 ClinicalTrials.gov number, NCT03142334.).


Assuntos
Antineoplásicos Imunológicos , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , Adjuvantes Imunológicos/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/cirurgia , Método Duplo-Cego , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/mortalidade , Neoplasias Renais/cirurgia , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Intervalo Livre de Doença , Terapia Combinada , Análise de Sobrevida
2.
Proc Natl Acad Sci U S A ; 121(3): e2314093121, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38190532

RESUMO

Lipid droplets (LDs) are organelles critical for energy storage and membrane lipid homeostasis, whose number and size are carefully regulated in response to cellular conditions. The molecular mechanisms underlying lipid droplet biogenesis and degradation, however, are not well understood. The Troyer syndrome protein spartin (SPG20) supports LD delivery to autophagosomes for turnover via lipophagy. Here, we characterize spartin as a lipid transfer protein whose transfer ability is required for LD degradation. Spartin copurifies with phospholipids and neutral lipids from cells and transfers phospholipids in vitro via its senescence domain. A senescence domain truncation that impairs lipid transfer in vitro also impairs LD turnover in cells while not affecting spartin association with either LDs or autophagosomes, supporting that spartin's lipid transfer ability is physiologically relevant. Our data indicate a role for spartin-mediated lipid transfer in LD turnover.


Assuntos
Autofagossomos , Gotículas Lipídicas , Autofagia , Lipídeos de Membrana
3.
Blood ; 143(16): 1646-1655, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38142448

RESUMO

ABSTRACT: Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by clonal proliferation of hematopoietic progenitor cells and is associated with an increased risk of thrombotic events (TEs). Established risk factors for TEs in patients with PV include advanced age, TE history, and elevated hematocrit. Although an association of TE with elevated white blood cell (WBC) counts has been suggested by retrospective studies, this relationship needs further validation. The prospective observational study of patients with polycythemia vera in US clinical practices (REVEAL) study collected prospective clinical data from 2510 patients with PV with a median follow-up of 44.7 months (range, 2-59 months) from enrollment. Using time-dependent covariate Cox proportional hazards models, blood counts were individually modeled with sex, age, disease duration, TE history at enrollment (baseline covariates), and treatment (time-dependent covariate). Analysis of 2271 participants identified 142 TEs in 106 patients. Significant associations with initial TE occurrence during the study period were observed for hematocrit level >45% (hazard ratio [HR], 1.84; 95% confidence interval [95% CI], 1.234-2.749; P = .0028) and WBCs >11 × 109/L (HR, 2.35; 95% CI, 1.598-3.465; P < .0001). Elevated WBC count was significantly associated with initial TE occurrence in both low-risk and high-risk PV. When hematocrit was controlled at ≤45%, WBC count >12 × 109/L was significantly associated with TE occurrence (HR, 1.95; 95% CI, 1.066-3.554; P = .0300). The results support incorporation of WBC count into PV risk stratification and studies of treatment strategies, and indicate the importance of controlling both hematocrit and WBC count in disease management. This trial was registered at www.clinicaltrials.gov as #NCT02252159.


Assuntos
Policitemia Vera , Trombose , Humanos , Policitemia Vera/tratamento farmacológico , Estudos Retrospectivos , Estudos Prospectivos , Trombose/etiologia , Fatores de Risco , Contagem de Leucócitos
4.
J Neurosci ; 44(32)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38960719

RESUMO

Little is known about the electrophysiologic activity of the intact human spinal cord during volitional movement. We analyzed epidural spinal recordings from a total of five human subjects of both sexes during a variety of upper extremity movements and found that these spinal epidural electrograms contain spectral information distinguishing periods of movement, rest, and sensation. Cervical epidural electrograms also contained spectral changes time-locked with movement. We found that these changes were primarily associated with increased power in the theta (4-8 Hz) band and feature increased theta phase to gamma amplitude coupling, and this increase in theta power can be used to topographically map distinct upper extremity movements onto the cervical spinal cord in accordance with established myotome maps of the upper extremity. Our findings have implications for the development of neurostimulation protocols and devices focused on motor rehabilitation for the upper extremity, and the approach presented here may facilitate spatiotemporal mapping of naturalistic movements.


Assuntos
Movimento , Humanos , Masculino , Feminino , Movimento/fisiologia , Adulto , Volição/fisiologia , Medula Cervical/fisiologia , Espaço Epidural/fisiologia , Vértebras Cervicais/fisiologia , Eletromiografia/métodos , Pessoa de Meia-Idade
5.
J Biol Chem ; 300(1): 105582, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38141762

RESUMO

The intracellular parasite, Toxoplasma gondii, has developed sophisticated molecular strategies to subvert host processes and promote growth and survival. During infection, T. gondii replicates in a parasitophorous vacuole (PV) and modulates host functions through a network of secreted proteins. Of these, Mitochondrial Association Factor 1b (MAF1b) recruits host mitochondria to the PV, a process that confers an in vivo growth advantage, though the precise mechanisms remain enigmatic. To address this knowledge gap, we mapped the MAF1b interactome in human fibroblasts using a commercial Yeast-2-hybrid (Y2H) screen, which revealed several previously unidentified binding partners including the GAP domain of Ral GTPase Accelerating Protein α1 (RalGAPα1(GAP)). Recombinantly produced MAF1b and RalGAPα1(GAP) formed as a stable binary complex as shown by size exclusion chromatography with a Kd of 334 nM as measured by isothermal titration calorimetry (ITC). Notably, no binding was detected between RalGAPα1(GAP) and the structurally conserved MAF1b homolog, MAF1a, which does not recruit host mitochondria. Next, we used hydrogen deuterium exchange mass spectrometry (HDX-MS) to map the RalGAPα1(GAP)-MAF1b interface, which led to identification of the "GAP-binding loop" on MAF1b that was confirmed by mutagenesis and ITC to be necessary for complex formation. A high-confidence Alphafold model predicts the GAP-binding loop to lie at the RalGAPα1(GAP)-MAF1b interface further supporting the HDX-MS data. Mechanistic implications of a RalGAPα1(GAP)-MAF1b complex are discussed in the context of T. gondii infection and indicates that MAF1b may have evolved multiple independent functions to increase T. gondii fitness.


Assuntos
Proteínas Ativadoras de GTPase , Mitocôndrias , Mapas de Interação de Proteínas , Proteínas de Protozoários , Toxoplasma , Humanos , Sítios de Ligação , Calorimetria , Cromatografia em Gel , Fibroblastos/metabolismo , Fibroblastos/parasitologia , Proteínas Ativadoras de GTPase/química , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Espectrometria de Massa com Troca Hidrogênio-Deutério , Mitocôndrias/metabolismo , Mitocôndrias/parasitologia , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Toxoplasma/química , Toxoplasma/genética , Toxoplasma/metabolismo , Técnicas do Sistema de Duplo-Híbrido
6.
J Am Chem Soc ; 146(31): 21651-21663, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39051542

RESUMO

Ferrocene is one of the most common electron donors, and mapping its ligand-field excited states is critical to designing donor-acceptor (D-A) molecules with long-lived charge transfer states. Although 3(d-d) states are commonly invoked in the photophysics of ferrocene complexes, mention of the high-spin 5(d-d) state is scarce. Here, we provide clear evidence of 5(d-d) formation in a bimetallic D-A molecule, ferrocenyl cobaltocenium hexafluorophosphate ([FcCc]PF6). Femtosecond optical transient absorption (OTA) spectroscopy reveals two distinct electronic excited states with 30 and 500 ps lifetimes. Using a combination of ultraviolet, visible, near-infrared, and short-wave infrared probe pulses, we capture the spectral features of these states over an ultrabroadband range spanning 320 to 2200 nm. Time-dependent density functional theory (DFT) calculations of the lowest triplet and quintet states, both primarily Fe(II) (d-d) in character, qualitatively agree with the experimental OTA spectra, allowing us to assign the 30 ps state as the 3(d-d) state and the 500 ps state as the high-spin 5(d-d) state. To confirm the ferrocene-centered high-spin character of the 500 ps state, we performed X-ray transient absorption (XTA) spectroscopy at the Fe and Co K edges. The Fe K-edge XTA spectrum at 150 ps shows a red shift of the absorption edge that is consistent with an Fe(II) high-spin state, as supported by ab initio calculations. The transient signal detected at the Co K-edge is 50× weaker, confirming the ferrocene-centered character of the excited state. Fitting of the transient extended X-ray absorption fine structure region yields an Fe-C bond length increase of 0.25 ± 0.1 Å in the excited state, as expected for the high-spin state based on DFT. Altogether, these results demonstrate that the high-spin state of ferrocene should be considered when designing donor-acceptor assemblies for photocatalysis and photovoltaics.

7.
J Exp Bot ; 75(8): 2527-2544, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38270266

RESUMO

Maintaining crop productivity is challenging as population growth, climate change, and increasing fertilizer costs necessitate expanding crop production to poorer lands whilst reducing inputs. Enhancing crops' nutrient use efficiency is thus an important goal, but requires a better understanding of related traits and their genetic basis. We investigated variation in low nutrient stress tolerance in a diverse panel of cultivated sunflower genotypes grown under high and low nutrient conditions, assessing relative growth rate (RGR) as performance. We assessed variation in traits related to nitrogen utilization efficiency (NUtE), mass allocation, and leaf elemental content. Across genotypes, nutrient limitation generally reduced RGR. Moreover, there was a negative correlation between vigor (RGR in control) and decline in RGR in response to stress. Given this trade-off, we focused on nutrient stress tolerance independent of vigor. This tolerance metric correlated with the change in NUtE, plasticity for a suite of morphological traits, and leaf element content. Genome-wide associations revealed regions associated with variation and plasticity in multiple traits, including two regions with seemingly additive effects on NUtE change. Our results demonstrate potential avenues for improving sunflower nutrient stress tolerance independent of vigor, and highlight specific traits and genomic regions that could play a role in enhancing tolerance.


Assuntos
Helianthus , Helianthus/genética , Locos de Características Quantitativas , Fenótipo , Genômica , Nitrogênio
8.
Langenbecks Arch Surg ; 409(1): 153, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38705912

RESUMO

PURPOSE: Transanal minimally invasive surgery has theoretical advantages for ileal pouch-anal anastomosis surgery. We performed a systematic review assessing technical approaches to transanal IPAA (Ta-IPAA) and meta-analysis comparing outcomes to transabdominal (abd-IPAA) approaches. METHODS: Three databases were searched for articles investigating Ta-IPAA outcomes. Primary outcome was anastomotic leak rate. Secondary outcomes included conversion rate, post operative morbidity, and length of stay (LoS). Staging, plane of dissection, anastomosis, extraction site, operative time, and functional outcomes were also assessed. RESULTS: Searches identified 13 studies with 404 unique Ta-IPAA and 563 abd-IPAA patients. Anastomotic leak rates were 6.3% and 8.4% (RD 0, 95% CI -0.066 to 0.065, p = 0.989) and conversion rates 2.5% and 12.5% (RD -0.106, 95% CI -0.155 to -0.057, p = 0.104) for Ta-IPAA and abd-IPAA. Average LoS was one day shorter (MD -1, 95% CI -1.876 to 0.302, p = 0.007). A three-stage approach was most common (47.6%), operative time was 261(± 60) mins, and total mesorectal excision and close rectal dissection were equally used (49.5% vs 50.5%). Functional outcomes were similar. Lack of randomised control trials, case-matched series, and significant study heterogeneity limited analysis, resulting in low to very low certainty of evidence. CONCLUSIONS: Analysis demonstrated the feasibility and safety of Ta-IPAA with reduced LoS, trend towards less conversions, and comparable anastomotic leak rates and post operative morbidity. Though results are encouraging, they need to be interpreted with heterogeneity and selection bias in mind. Robust randomised clinical trials are warranted to adequately compare ta-IPAA to transabdominal approaches.


Assuntos
Fístula Anastomótica , Proctocolectomia Restauradora , Humanos , Proctocolectomia Restauradora/métodos , Proctocolectomia Restauradora/efeitos adversos , Fístula Anastomótica/etiologia , Cirurgia Endoscópica Transanal/métodos , Cirurgia Endoscópica Transanal/efeitos adversos , Resultado do Tratamento , Tempo de Internação/estatística & dados numéricos , Bolsas Cólicas/efeitos adversos , Duração da Cirurgia , Anastomose Cirúrgica/métodos
9.
Langenbecks Arch Surg ; 409(1): 32, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38191937

RESUMO

PURPOSE: Transanal minimally invasive surgery (TAMIS) is an advanced transanal platform that can be utilised to perform high-quality local excision (LE) of rectal neoplasia. This study describes clinical and midterm oncological outcomes from a single unit's 7-year experience with TAMIS. METHODS: Consecutive patients who underwent TAMIS LE at our institution between January 1st, 2016, and December 31st, 2022, were identified from a prospectively maintained database. Indication for TAMIS LE was benign lesions not amenable to endoscopic excision or histologically favourable early rectal cancers. The primary endpoints were resection quality, disease recurrence and peri-operative outcomes. The Kaplan-Meier survival analyses were used to describe disease-free survival (DFS) for patients with rectal adenocarcinoma that did not receive immediate salvage proctectomy. RESULTS: There were 168 elective TAMIS LE procedures performed for 102 benign and 66 malignant lesions. Overall, a 95.2% negative margin rate was observed, and 96.4% of lesions were submitted without fragmentation. Post-operative morbidity was recorded in 8.3% of patients, with post-operative haemorrhage, being the most common complication encountered. The mean follow-up was 17 months (SD 15). Local recurrence occurred in 1.6%, and distant organ metastasis was noted in 1.6% of patients. CONCLUSIONS: For carefully selected patients, TAMIS for local excision of early rectal neoplasia is a valid option with low morbidity that maintains the advantages of organ preservation.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Protectomia , Neoplasias Retais , Humanos , Recidiva Local de Neoplasia/cirurgia , Neoplasias Retais/cirurgia , Bases de Dados Factuais
10.
Ann Diagn Pathol ; 71: 152302, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38642469

RESUMO

BACKGROUND: Reliably distinguishing primary ovarian mucinous neoplasms (POMNs) from metastatic colorectal cancers (CRCs) is both challenging to the histopathologist and of great clinical importance. Special AT-rich sequence binding protein-2 (SATB2) has emerged as a useful diagnostic immunohistochemical marker of colorectal cancer. This meta-analysis compares SATB2 expression in POMNs and CRC. METHODS: A systematic literature search for relevant studies was conducted. Meta-analysis of SATB2 positivity was undertaken using a random effects model. RESULTS: Seven studies including 711 CRCs and 528 POMNs were included. SATB2 positivity was seen in 81 % (95 % CI: 72-88 %) of CRCs and 4 % (95 % CI: 1-11 %) of POMNs. Variation was seen in immunohistochemical methods used for SATB2 detection and threshold for positivity. CONCLUSION: SATB2 staining remains high in CRC and low in POMNs, supporting its use in differentiating these two pathologies with vastly differing prognosis and treatment.


Assuntos
Adenocarcinoma Mucinoso , Biomarcadores Tumorais , Neoplasias Colorretais , Imuno-Histoquímica , Proteínas de Ligação à Região de Interação com a Matriz , Neoplasias Ovarianas , Fatores de Transcrição , Humanos , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/diagnóstico , Feminino , Imuno-Histoquímica/métodos , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/análise , Fatores de Transcrição/metabolismo , Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/diagnóstico , Diagnóstico Diferencial
11.
Haematologica ; 109(7): 2284-2289, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38268449
12.
AoB Plants ; 16(4): plae031, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39011498

RESUMO

Drought is a major agricultural challenge that is expected to worsen with climate change. A better understanding of drought responses has the potential to inform efforts to breed more tolerant plants. We assessed leaf trait variation and covariation in cultivated sunflower (Helianthus annuus L.) in response to water limitation. Plants were grown under four levels of water availability and assessed for environmentally induced plasticity in leaf stomatal and vein traits as well as biomass (performance indicator), mass fractions, leaf area, leaf mass per area, and chlorophyll content. Overall, biomass declined in response to stress; these changes were accompanied by responses in leaf-level traits including decreased leaf area and stomatal size, and increased stomatal and vein density. The magnitude of trait responses increased with stress severity and relative plasticity of smaller-scale leaf anatomical traits was less than that of larger-scale traits related to construction and growth. Across treatments, where phenotypic plasticity was observed, stomatal density was negatively correlated with stomatal size and positively correlated with minor vein density, but the correlations did not hold up within treatments. Four leaf traits previously shown to reflect major axes of variation in a large sunflower diversity panel under well-watered conditions (i.e. stomatal density, stomatal pore length, vein density, and leaf mass per area) predicted a surprisingly large amount of the variation in biomass across treatments, but trait associations with biomass differed within treatments. Additionally, the importance of these traits in predicting variation in biomass is mediated, at least in part, through leaf size. Our results demonstrate the importance of leaf anatomical traits in mediating drought responses in sunflower, and highlight the role that phenotypic plasticity and multi-trait phenotypes can play in predicting productivity under complex abiotic stresses like drought.

13.
Geroscience ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488947

RESUMO

INTRODUCTION: The dialysis disequilibrium syndrome (DDS) is a complication in those undergoing dialysis for chronic kidney disease (CKD) or acute kidney injury (AKI), characterized by nonspecific symptoms that may progress to coma and death secondary to cerebral edema. This syndrome is associated with rapid change in electrolytes during dialysis with changes in intracranial pressure (ICP) and may have a higher incidence in the elderly neurosurgical patient population. METHODS: Literature review and illustrative case example. RESULTS: A 62-year-old female presented with acute mental status change during hemodialysis (HD), with a history of a nonsurgical acute subdural hematoma (SDH) 10 days prior. Imaging showed a conversion of the acute SDH to chronic SDH of 12.2 mm in size with a 14.1 midline shift, for which she underwent a hemicraniectomy with SDH evacuation, with a gradual return to baseline. The literature review identified 5 publications meeting the inclusion criteria. Major theories of DDS include a reverse urea effect, intracerebral acidosis, idiogenic osmoles, and local inflammation. This complication may occur more frequently in the elderly neurosurgical patient population, likely due to age-related comorbidities, preexisting neurological insult, and increased permeability of the blood-brain barrier (BBB), leading to cerebral edema. CONCLUSION: DDS is a rare and potentially fatal complication of HD that may have a higher incidence in the elderly neurosurgical patient population, yet remains to be fully understood. Further study is recommended to characterize the pathophysiological mechanism and incidence of DDS in neurosurgical patients.

14.
Eur J Gastroenterol Hepatol ; 36(5): 578-583, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489595

RESUMO

OBJECTIVE: Colectomy for ulcerative colitis (UC) is common despite therapeutic advances. Post-operative morbidity and mortality demonstrate an association between hospital volumes and outcomes. This single-centre retrospective study examines outcomes after emergency colectomy for UC. METHODS: Patient demographics, perioperative variables and outcomes were collected in Beaumont Hospital between 2010 and 2023. Univariant analysis was used to assess relationships between perioperative variables and morbidity and length of stay (LOS). RESULTS: A total of 115 patients underwent total abdominal colectomy with end ileostomy for UC, 8.7 (±3.8) per annum. Indications were refractory acute severe colitis (88.7%), toxic megacolon (6.1%), perforation (4.3%), or obstruction (0.9%). Over 80% of cases were performed laparoscopically. Pre-operative steroid (93%) and biologic (77.4%) use was common. Median post-operative LOS was 8 days (interquartile range 6-12). There were no 30-day mortalities, and 30-day post-operative morbidity was 38.3%. There was no association between time to colectomy ( P  = 0.85) or biologic use ( P  = 0.24) and morbidity. Increasing age was associated with prolonged LOS ( P  = 0.01). Laparoscopic approach (7 vs. 12 days P  =0.01, 36.8% vs. 45% P  = 0.66) was associated with reduced LOS and morbidity. CONCLUSION: This study highlights contemporary outcomes after emergency colectomy for UC at a specialist high-volume, tertiary referral centre, and superior outcomes after laparoscopic surgery in the biologic era.


Assuntos
Produtos Biológicos , Colite Ulcerativa , Humanos , Colite Ulcerativa/cirurgia , Estudos Retrospectivos , Centros de Atenção Terciária , Resultado do Tratamento , Colectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia
15.
Eur J Gastroenterol Hepatol ; 36(7): 861-866, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38625823

RESUMO

Transanal minimally invasive surgery (TAMIS) is a surgical alternative to proctectomy in the management of complex rectal polyps and early rectal cancers. In 2016, our institution introduced a TAMIS programme. The purpose of this study was to evaluate changes in practice and outcomes in our institution in the 3 years before and after the implementation of TAMIS. We conducted a retrospective analysis of a prospective database of patients who underwent proctectomy or TAMIS for the management of complex rectal polyps or early rectal cancers at our institution between 2013 and 2018. 96 patients were included in this study (41 proctectomy vs 55 TAMIS). A significant reduction was noted in the number of proctectomies performed in the 3 years after the implementation of TAMIS as compared to the 3 years before (13 vs 28) ( P  < 0.001); 43% of patients ( n  = 12) who underwent proctectomy in the period prior to implementation of TAMIS were American Society of Anaesthesiologists grade III, as compared to only 15% ( n  = 2) of patients during the period following TAMIS implementation ( P  = 0.02). TAMIS was associated with a significant reduction in length of inpatient stay ( P  < 0.001). Oncological outcomes were comparable between groups (log rank P  = 0.83). Our findings support TAMIS as a safe and effective alternative to radical resection. The availability of TAMIS has resulted in a significant reduction in the number of comorbid patients undergoing proctectomy at our institution. Consequently, we have observed a significant reduction in postoperative complications over this time period.


Assuntos
Tempo de Internação , Protectomia , Neoplasias Retais , Centros de Atenção Terciária , Cirurgia Endoscópica Transanal , Humanos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Cirurgia Endoscópica Transanal/métodos , Protectomia/métodos , Protectomia/efeitos adversos , Resultado do Tratamento , Complicações Pós-Operatórias/etiologia , Pólipos Intestinais/cirurgia , Pólipos Intestinais/patologia , Fatores de Tempo , Bases de Dados Factuais , Avaliação de Programas e Projetos de Saúde
16.
World Neurosurg ; 186: 166-171, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38522790

RESUMO

BACKGROUND: Schwannomas are benign peripheral nerve sheath tumors arising from myelinating Schwann cells. Although macrocystic changes are regularly encountered in schwannoma variants such as vestibular nerve tumors, they are exceedingly rare among spinal neoplasms. METHODS: Case report and systematic review of 4 databases (Ovid Medline, PubMed, Science Direct, and SCOPUS) from inception to present. All peer-reviewed publications reporting intradural cystic thoracic schwannoma were included. RESULTS: We identified 8 publications documenting 9 cases of cystic thoracic schwannoma. Four were female, 5 male; median age was 41 years (range, 27-80). Presentations ranged from incidental to pain, sensory changes, lower extremity paresis, or bowel/bladder dysfunction. Characteristic radiographic findings included T1 hypointensity, T2 hyperintensity, and cord effacement or compression. The present case followed a similar pattern: a 52-year-old male presented with worsening bilateral lower extremity weakness, low back pain, and gait dysfunction, worsening over 3 days. Examination also revealed decreased left lower extremity sensation. Imaging identified a well-delineated intradural, extramedullary macrocystic extending over T7-T10. The patient underwent a laminectomy resulting in complete tumor resection and restoration of intact neurologic function. Final pathology confirmed benign cystic schwannoma. CONCLUSIONS: Macrocystic thoracic schwannomas are exceedingly rare and lack a comprehensive scheme for clinical classification of their natural history and pathogenesis. We report the 10th case of such a schwannoma, and the first associated systematic review. Although macrocystic thoracic schwannomas are not frequently encountered, accurate diagnosis and appropriate neurosurgical treatment is critical in these vulnerable patients, given the opportunity for excellent functional outcomes following neurosurgical treatment.


Assuntos
Neurilemoma , Vértebras Torácicas , Humanos , Neurilemoma/cirurgia , Neurilemoma/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Vértebras Torácicas/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Feminino , Neoplasias da Medula Espinal/cirurgia , Neoplasias da Medula Espinal/diagnóstico por imagem , Neoplasias da Medula Espinal/patologia , Adulto , Idoso
17.
CPT Pharmacometrics Syst Pharmacol ; 13(6): 919-925, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38790133

RESUMO

Immune checkpoint inhibitors block the interaction between a receptor on one cell and its ligand on another cell, thus preventing the transduction of an immunosuppressive signal. While inhibition of the receptor-ligand interaction is key to the pharmacological activity of these drugs, it can be technically challenging to measure these intercellular interactions directly. Instead, target engagement (or receptor occupancy) is commonly measured, but may not always be an accurate predictor of receptor-ligand inhibition, and can be misleading when used to inform clinical dose projections for this class of drugs. In this study, a mathematical model explicitly representing the intercellular receptor-ligand interaction is used to compare dose prediction based on target engagement or receptor-ligand inhibition for two checkpoint inhibitors, atezolizumab and magrolimab. For atezolizumab, there is little difference between target engagement and receptor-ligand inhibition, but for magrolimab, the model predicts that receptor-ligand inhibition is significantly less than target engagement. The key variables explaining the difference between these two drugs are the relative concentrations of the target receptors and their ligands. Drug-target affinity and receptor-ligand affinity can also have divergent effects on target engagement and inhibition. These results suggest that it is important to consider ligand-receptor inhibition in addition to target engagement and demonstrate the impact of using modeling for efficacious dose estimation.


Assuntos
Anticorpos Monoclonais Humanizados , Inibidores de Checkpoint Imunológico , Humanos , Inibidores de Checkpoint Imunológico/administração & dosagem , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/farmacocinética , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacologia , Ligantes , Relação Dose-Resposta a Droga , Modelos Teóricos
18.
Cancers (Basel) ; 16(4)2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38398139

RESUMO

The study cohort consisted of 83 patients with a mean age of 49.55 (SD 13.72) with a female preponderance (60 patients). Here, 32.14% of patients had primary LTS; the remaining were metastases. Clinical presentation included nonspecific back pain (57.83%), weakness (21.69%) and radicular pain (18.07%). History of uterine neoplasia was found in 33.73% of patients. LTS preferentially affected the thoracic spine (51.81%), followed by the lumbar (21.67%) spine. MRI alone was the most common imaging modality (33.33%); in other cases, it was used with CT (22.92%) or X-ray (16.67%); 19.23% of patients had Resection/Fixation, 15.38% had Total en bloc spondylectomy, and 10.26% had Corpectomy. A minority of patients had laminectomy and decompression. Among those with resection, 45.83% had a gross total resection, 29.17% had a subtotal resection, and 16.67% had a near total resection. Immunohistochemistry demonstrated positivity for actin (43.37%), desmin (31.33%), and Ki67 (25.30). At a follow-up of 19.3 months, 61.97% of patients were alive; 26.25% of 80 patients received no additional treatment, 23.75% received combination radiotherapy and chemotherapy, only chemotherapy was given to 20%, and radiotherapy was given to 17.5%. Few (2.5%) had further resection. For an average of 12.50 months, 42.31% had no symptoms, while others had residual (19.23%), other metastasis (15.38%), and pain (7.69%). On follow-up of 29 patients, most (68.97%) had resolved symptoms; 61.97% of the 71 patients followed were alive.

19.
Gut Microbes ; 16(1): 2350149, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38709233

RESUMO

Mucinous colorectal cancer (CRC) is a common histological subtype of colorectal adenocarcinoma, associated with a poor response to chemoradiotherapy. The commensal facultative anaerobes fusobacteria, have been associated with poor prognosis specifically in mesenchymal CRC. Interestingly, fusobacterial infection is especially prevalent in mucinous CRC. The objective of this study was therefore to increase our understanding of beneficial and detrimental effects of fusobacterial infection, by contrasting host cell signaling and immune responses in areas of high vs. low infection, using mucinous rectal cancer as a clinically relevant example. We employed spatial transcriptomic profiling of 106 regions of interest from 8 mucinous rectal cancer samples to study gene expression in the epithelial and immune segments across regions of high versus low fusobacterial infection. Fusobacteria high regions were associated with increased oxidative stress, DNA damage, and P53 signaling. Meanwhile regions of low fusobacterial prevalence were characterized by elevated JAK-STAT, Il-17, Il-1, chemokine and TNF signaling. Immune masks within fusobacterial high regions were characterized by elevated proportions of cytotoxic (CD8+) T cells (p = 0.037), natural killer (NK) cells (p < 0.001), B-cells (p < 0.001), and gamma delta T cells (p = 0.003). Meanwhile, fusobacteria low regions were associated with significantly greater M2 macrophage (p < 0.001), fibroblast (p < 0.001), pericyte (p = 0.002), and endothelial (p < 0.001) counts.


Assuntos
Dano ao DNA , Perfilação da Expressão Gênica , Neoplasias Retais , Transdução de Sinais , Humanos , Neoplasias Retais/genética , Neoplasias Retais/imunologia , Neoplasias Retais/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Transcriptoma , Idoso
20.
bioRxiv ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38746453

RESUMO

The lipid kinase phosphatidylinositol 4 kinase III alpha (PI4KIIIa/PI4KA) is a master regulator of the lipid composition and asymmetry of the plasma membrane. PI4KA exists primarily in a heterotrimeric complex with its regulatory proteins TTC7 and FAM126. Fundamental to PI4KA activity is its targeted recruitment to the plasma membrane by the lipidated proteins EFR3A and EFR3B. Here, we report a cryo-EM structure of the C-terminus of EFR3A bound to the PI4KA-TTC7B-FAM126A complex, with extensive validation using both hydrogen deuterium exchange mass spectrometry (HDX-MS), and mutational analysis. The EFR3A C-terminus undergoes a disorder-order transition upon binding to the PI4KA complex, with an unexpected direct interaction with both TTC7B and FAM126A. Complex disrupting mutations in TTC7B, FAM126A, and EFR3 decrease PI4KA recruitment to the plasma membrane. Multiple post-translational modifications and disease linked mutations map to this site, providing insight into how PI4KA membrane recruitment can be regulated and disrupted in human disease.

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