Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 381
Filtrar
1.
Nat Commun ; 15(1): 8718, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379361

RESUMO

BamA is the central component of the essential ß-barrel assembly machine (BAM), a conserved multi-subunit complex that dynamically inserts and folds ß-barrel proteins into the outer membrane of Gram-negative bacteria. Despite recent advances in our mechanistic and structural understanding of BamA, there are few potent and selective tool molecules that can bind to and modulate BamA activity. Here, we explored in vitro selection methods and different BamA/BAM protein formulations to discover peptide macrocycles that kill Escherichia coli by targeting extreme conformational states of BamA. Our studies show that Peptide Targeting BamA-1 (PTB1) targets an extracellular divalent cation-dependent binding site and locks BamA into a closed lateral gate conformation. By contrast, PTB2 targets a luminal binding site and traps BamA into an open lateral gate conformation. Our results will inform future antibiotic discovery efforts targeting BamA and provide a template to prospectively discover modulators of other dynamic integral membrane proteins.


Assuntos
Proteínas da Membrana Bacteriana Externa , Proteínas de Escherichia coli , Escherichia coli , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas da Membrana Bacteriana Externa/química , Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Sítios de Ligação , Antibacterianos/farmacologia , Antibacterianos/química , Conformação Proteica , Peptídeos/química , Peptídeos/metabolismo , Peptídeos/farmacologia , Ligação Proteica , Modelos Moleculares
2.
J Foot Ankle Surg ; 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39288843

RESUMO

Little is known regarding outcomes of talus fracture management among patients with diabetes mellitus. This study aimed to compare post-operative outcomes after open reduction and internal fixation for talus fracture in patients with complicated diabetes, uncomplicated diabetes, and patients without diabetes. We used the PearlDiver database to identify patients who underwent operative repair of talus fractures from 2009 to 2021. Complications were evaluated at 30-days, 90-days, and 1 year of surgery. As we performed multiple separate analyses, to minimize the risk of type 1 error we employed the Bonferroni correction for statistical significance (p< 0.017). The PearlDiver identified 5,232 patients with talus fracture that underwent open reduction internal fixation. Stratified by diabetes status, the "complicated diabetes," "uncomplicated diabetes," and "no diabetes" groups contained 223, 418, and 4591 patients, respectively. Reoperation, acute kidney injury, and myocardial infarction were increased among diabetes patients compared to non-diabetes patients, irrespective of diabetes severity within 3 months of surgery. Furthermore, patients with complicated diabetes were more likely to develop sepsis and wound disruption compared to their non-diabetes counterparts within 3 months. While not statistically significant, complicated diabetes patients were diagnosed with talar non-union at higher rates compared with non-diabetes patients. Further analysis may reveal a clinically significant discrepancy in non-union between these groups. Complicated diabetes is associated with significantly higher risk of multiple adverse events following talus fracture repair. LEVEL OF CLINICAL EVIDENCE: 3.

3.
Environ Sci Technol Lett ; 11(9): 948-953, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39280077

RESUMO

Successful reduction of oil and gas sector methane emissions to meet near-zero intensity targets requires the identification and mitigation of all possible sources. One potentially important source is catalytic heaters, which have largely escaped attention in regulatory and mitigation efforts despite being ubiquitous at upstream production sites in cold climate regions. This study reports direct in situ measurements of the exhaust streams of 38 natural gas-fired catalytic heaters at upstream production sites in British Columbia, Canada. All heaters in the sample showed consistently poor methane conversion with mean destruction efficiencies of 61 ± 5% while releasing 235 [+31/-28] g of methane per cubic meter of fuel. Although individual units are generally small methane sources (mean of 0.28 ± 0.04 kg/h), their prevalence means they could represent 6% of the total provincial upstream methane inventory and as an aggregate methane source could be 5× more significant than abandoned wells. Notably, these heaters are seasonal sources whose emissions would be missed in measurement campaigns occurring solely in summer months. However, additional measurements from a small number of heat medium burners demonstrate that, where feasible, methane emissions can be reduced by approximately 425× by replacing catalytic heaters with centralized heat systems.

4.
Nicotine Tob Res ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39171360

RESUMO

INTRODUCTION: The tobacco industry has a long history of circumventing regulations to present their products, inaccurately, as less harmful. Greenwashing (portraying a product as natural/eco-friendly) is increasingly used by tobacco companies and may mislead consumers to believe that certain cigarettes are less harmful than others. This study assesses the effect of some common greenwashing tactics on consumer product perceptions. METHODS: We conducted an online experiment with 1,504 participants ages 18-29, randomized to view a cigarette ad manipulated for presence/absence of a combination of 4 different greenwashing techniques: greenwashed ad text, greenwashed ad imagery, recycled paper ad background, and image of greenwashed cigarette pack. Participants rated perceived absolute harm, relative harm to other cigarettes, absolute addictiveness, relative addictiveness, and relative nicotine content. RESULTS: Participants who viewed ads containing greenwashed text were more likely to have inaccurate perceptions about absolute harm (AOR=1.72), relative harm (AOR=3.92), relative addictiveness (AOR=2.93) and nicotine content (AOR=2.08). Participants who viewed ads containing greenwashed imagery were more likely to have inaccurate perceptions of relative harm (AOR=1.55), absolute addictiveness (AOR=1.72), relative addictiveness (AOR=1.60) and nicotine content (AOR=1.48). Forty-two percent of those who saw an ad with all greenwashed features believed the product was less harmful than other cigarettes vs. 2% of those who saw an ad without greenwashed features. CONCLUSIONS: We found greenwashed text and imagery produced inaccurate risk perceptions. More active U.S. Food & Drug Administration (FDA) enforcement against such greenwashing and new FDA rulemaking to prohibit unnecessary imagery in tobacco advertising and establish plain packaging requirements would help protect consumers and public health. IMPLICATIONS: These findings provide evidence that greenwashing tactics used by the tobacco industry increase inaccurate product risk perceptions. These tactics could be a way for the industry to make implicit modified risk claims, despite applicable U.S. Family Smoking Prevention and Tobacco Control Act prohibitions. Findings from this study support the need for prohibitions on these tactics, and the potential for such prohibitions to help protect public health.

5.
Sci Rep ; 14(1): 18477, 2024 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-39122771

RESUMO

Measurement of cellular resting membrane potential (RMP) is important in understanding ion channels and their role in regulation of cell function across a wide range of cell types. However, methods available for the measurement of RMP (including patch clamp, microelectrodes, and potential-sensitive fluorophores) are expensive, slow, open to operator bias, and often result in cell destruction. We present non-contact, label-free membrane potential estimation which uses dielectrophoresis to determine the cytoplasm conductivity slope as a function of medium conductivity. By comparing this to patch clamp data available in the literature, we have demonstratet the accuracy of this approach using seven different cell types, including primary suspension cells (red blood cells, platelets), cultured suspension cells (THP-1), primary adherent cells (chondrocytes, human umbilical mesenchymal stem cells), and adherent (HeLa) and suspension (Jurkat) cancer cell lines. Analysis of the effect of ion channel inhibitors suggests the effects of pharmaceutical agents (TEA on HeLa; DMSO and neuraminidase on red blood cells) can also be measured. Comparison with published values of membrane potential suggest that the differences between our estimates and values recorded by patch clamp are accurate to within published margins of error. The method is low-cost, non-destructive, operator-independent and label-free, and has previously been shown to allow cells to be recovered after measurement.


Assuntos
Eletroforese , Potenciais da Membrana , Humanos , Potenciais da Membrana/fisiologia , Eletroforese/métodos , Células HeLa , Células Jurkat , Técnicas de Patch-Clamp/métodos , Eritrócitos/citologia , Eritrócitos/metabolismo
6.
Vet Surg ; 53(6): 1052-1061, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39088191

RESUMO

OBJECTIVE: To compare the efficacy and clinical outcomes of computed tomography (CT)-based virtual surgical planning (VSP) and a three-dimensional (3D)-printed, patient-specific reduction system to conventional indirect reduction techniques for diaphyseal tibial fractures stabilized using minimally invasive plate osteosynthesis (MIPO) in dogs. STUDY DESIGN: A prospective clinical study with a historic control cohort. SAMPLE POPULATION: Dogs undergoing MIPO stabilization of diaphyseal tibial fractures using a custom 3D-printed reduction system (3D-MIPO; n = 15) or conventional indirect reduction techniques (c-MIPO; n = 14). METHODS: Dogs were prospectively enrolled to the 3D-MIPO group and CT scans were used to design and fabricate a custom 3D-printed reduction system to facilitate MIPO. Medical records were searched to identify dogs for the c-MIPO group. Pre-, intra- and postoperative parameters were compared between groups. RESULTS: The duration from presentation until surgery was 23 h longer in the 3D-MIPO group (p = .002). Fewer intraoperative fluoroscopic images were acquired (p < .001) and mean surgical duration was 34 min shorter in the 3D-MIPO group (p = .014). Median postoperative tibial length, frontal alignment, and sagittal alignment were within 4 mm, 3° and 3°, respectively, of the contralateral tibia in both groups and did not differ between reduction groups (p > .1). Postoperative complications occurred in 27% and 14% of fractures in the 3D-MIPO and c-MIPO groups, respectively. CONCLUSION: Both reduction methods yielded comparable results. Although the preoperative planning and guide preparation was time consuming, surgery times were shorter and fluoroscopy use was less in the 3D-MIPO group. CLINICAL SIGNIFICANCE: VSP and the custom 3D-printed reduction system facilitated efficient MIPO.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas , Impressão Tridimensional , Fraturas da Tíbia , Animais , Cães/cirurgia , Cães/lesões , Fixação Interna de Fraturas/veterinária , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/veterinária , Fraturas da Tíbia/diagnóstico por imagem , Placas Ósseas/veterinária , Masculino , Feminino , Estudos de Casos e Controles , Estudos Prospectivos , Tomografia Computadorizada por Raios X/veterinária , Procedimentos Cirúrgicos Minimamente Invasivos/veterinária , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Doenças do Cão/cirurgia , Cirurgia Assistida por Computador/veterinária , Cirurgia Assistida por Computador/métodos
7.
Vet Surg ; 53(6): 1039-1051, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38850094

RESUMO

OBJECTIVE: To evaluate the efficacy of a three-dimensional (3D)-printed, patient-specific reduction system for aligning diaphyseal tibial fractures stabilized using minimally invasive plate osteosynthesis (MIPO). STUDY DESIGN: Prospective clinical trial. SAMPLE POPULATION: Fifteen client owned dogs. METHODS: Virtual 3D models of both pelvic limbs were created. Pin guides were designed to conform to the proximal and distal tibia. A reduction bridge was designed to align the pin guides based on the guides' spatial location. Guides were 3D printed, sterilized, and applied, in conjunction with transient application of a circular fixator, to facilitate indirect fracture realignment before plate application. Alignment of the stabilized tibiae was assessed using postoperative computed tomography scans. RESULTS: Mean duration required for virtual planning was 2.5 h and a mean of 50.7 h elapsed between presentation and surgery. Guide placement was accurate with minor median discrepancies in translation and frontal, sagittal, and axial plane positioning of 2.9 mm, 3.6°, 2.7°, and 6.8°, respectively. Application of the reduction system restored mean tibial length and frontal, sagittal, and axial alignment within 1.7 mm, 1.9°, 1.7°, and 4.5°, respectively, of the contralateral tibia. CONCLUSION: Design and fabrication of a 3D-printed, patient-specific fracture reduction system is feasible in a relevant clinical timeline. Intraoperative pin-guide placement was reasonably accurate with minor discrepancies compared to the virtual plan. Custom 3D-printed reduction system application facilitated near-anatomic or acceptable fracture reduction in all dogs. CLINICAL SIGNIFICANCE: Virtual planning and fabrication of a 3D-printing patient-specific fracture reduction system is practical and facilitated acceptable, if not near-anatomic, fracture alignment during MIPO.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas , Impressão Tridimensional , Fraturas da Tíbia , Animais , Cães/lesões , Cães/cirurgia , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/veterinária , Fixação Interna de Fraturas/veterinária , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Placas Ósseas/veterinária , Estudos Prospectivos , Masculino , Feminino , Procedimentos Cirúrgicos Minimamente Invasivos/veterinária , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação
8.
AJR Am J Roentgenol ; 223(2): e2431272, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38899842

RESUMO

BACKGROUND. Differences in survival and morbidity among treatment options (ablation, surgical resection, and transplant) for early-stage hepatocellular carcinoma (HCC) have been well studied. Additional understanding of the costs of such care would help to identify drivers of high costs and potential barriers to care delivery. OBJECTIVE. The purpose of this article was to quantify total and patient out-of-pocket costs for ablation, surgical resection, and transplant in the management of early-stage HCC and to identify factors predictive of these costs. METHODS. This retrospective U.S. population-based study used the SEER-Medicare linked dataset to identify a sample of 1067 Medicare beneficiaries (mean age, 73 years; 674 men, 393 women) diagnosed with early-stage HCC (size ≤ 5 cm) treated with ablation (n = 623), resection (n = 201), or transplant (n = 243) between January 2009 and December 2016. Total costs and patient out-of-pocket costs for the index procedure as well as for any care within 30 and 90 days after the procedure were identified and stratified by treatment modality. Additional comparisons were performed among propensity score-matched subgroups of patients treated by ablation or resection (each n = 172). Multivariable linear regression models were used to identify factors predictive of total costs and out-of-pocket costs for index procedures as well as for 30- and 90-day post-procedure periods. RESULTS. For ablation, resection, and transplant, median index-procedure total cost was US$6689, US$25,614, and US$66,034; index-procedure out-of-pocket cost was US$1235, US$1650, and US$1317; 30-day total cost was US$9456, US$29,754, and US$69,856; 30-day out-of-pocket cost was US$1646, US$2208, and US$3198; 90-day total cost was US$14,572, US$34,984, and US$88,103; and 90-day out-of-pocket cost was US$2138, US$2462, and US$3876, respectively (all p < .001). In propensity score-matched subgroups, ablation and resection had median index-procedure, 30-day, and 90-day total costs of US$6690 and US$25,716, US$9995 and US$30,365, and US$15,851 and US$34,455, respectively. In multivariable analysis adjusting for socioeconomic factors, comorbidities, and liver-disease prognostic indicators, surgical treatment (resection or transplant) was predictive of significantly greater costs compared with ablation at all time points. CONCLUSION. Total and out-of-pocket costs for index procedures as well as for 30-day and 90-day postprocedure periods were lowest for ablation, followed by resection and then transplant. CLINICAL IMPACT. This comprehensive cost analysis could help inform future cost-effectiveness analyses.


Assuntos
Carcinoma Hepatocelular , Gastos em Saúde , Neoplasias Hepáticas , Transplante de Fígado , Medicare , Programa de SEER , Humanos , Masculino , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/economia , Feminino , Estados Unidos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/economia , Medicare/economia , Idoso , Estudos Retrospectivos , Transplante de Fígado/economia , Hepatectomia/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Idoso de 80 Anos ou mais , Estadiamento de Neoplasias , Técnicas de Ablação/economia
9.
Am J Surg Pathol ; 48(7): 825-833, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38808927

RESUMO

Penile melanomas (PM) are an exceedingly rare subtype of mucosal melanoma (MM), and we reviewed the clinicopathologic features and molecular profile in 8 PMs. The patient ages ranged from 46 to 78 (mean: 62.8) years with involvement on the glans (n=5; 62.5%), penile urethra (n=2; 25%), and foreskin (n=1, 12.5%). Tumor depth ranged from 1.6 to 10.0 (mean: 5.25) mm. Most of the patients underwent partial penectomy (n=6; 75%) and sentinel lymph node (LN) biopsy N=7; 87.5%). Seven patients had metastatic disease at diagnosis, 6 involving LNs and 1 the adrenal gland, and 4 died of disease with a mean follow-up period of 40.5 (2 to 95) months. Five of 7 (71%) cases identified 15 molecular alterations within KIT , CDKN2A , NF1 , PTEN , and APC (n=2 each), and NRAS , MAP3K1 , CDH1 , MSH6 , and TERT (n=1 each). Two cases were not found to harbor genetic aberrations, and 1 case failed testing. In addition, we reviewed the English literature and included 93 cases with a reported depth of invasion and follow-up. A total of 101 PMs were analyzed for prognostic parameters, and the overall survival was significantly worse in patients with LN metastasis (P=0.0008), distant metastasis (P=0.0016), and greater depth of invasion (P=0.0222) based upon T-stage. While T4 conferred substantially worse survival, the delineation of the survival curves between T2 and T3 was less clear, and combining T2+T3 disease had a strong prognostic impact ( P =0.0024). Prognostic parameters used in the staging of cutaneous melanomas may also be used in PMs. An alternative staging system expanding the inclusion criteria for T2 might provide a more accurate prognostic stratification.


Assuntos
Biomarcadores Tumorais , Melanoma , Estadiamento de Neoplasias , Neoplasias Penianas , Humanos , Masculino , Neoplasias Penianas/patologia , Neoplasias Penianas/mortalidade , Neoplasias Penianas/genética , Neoplasias Penianas/cirurgia , Melanoma/genética , Melanoma/patologia , Melanoma/mortalidade , Pessoa de Meia-Idade , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Biópsia de Linfonodo Sentinela , Metástase Linfática , Valor Preditivo dos Testes , Imuno-Histoquímica , Fatores de Tempo
10.
Cell Death Dis ; 15(5): 379, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816421

RESUMO

CSMD1 (Cub and Sushi Multiple Domains 1) is a well-recognized regulator of the complement cascade, an important component of the innate immune response. CSMD1 is highly expressed in the central nervous system (CNS) where emergent functions of the complement pathway modulate neural development and synaptic activity. While a genetic risk factor for neuropsychiatric disorders, the role of CSMD1 in neurodevelopmental disorders is unclear. Through international variant sharing, we identified inherited biallelic CSMD1 variants in eight individuals from six families of diverse ancestry who present with global developmental delay, intellectual disability, microcephaly, and polymicrogyria. We modeled CSMD1 loss-of-function (LOF) pathogenesis in early-stage forebrain organoids differentiated from CSMD1 knockout human embryonic stem cells (hESCs). We show that CSMD1 is necessary for neuroepithelial cytoarchitecture and synchronous differentiation. In summary, we identified a critical role for CSMD1 in brain development and biallelic CSMD1 variants as the molecular basis of a previously undefined neurodevelopmental disorder.


Assuntos
Deficiência Intelectual , Proteínas de Membrana , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Feminino , Masculino , Transtornos do Neurodesenvolvimento/genética , Alelos , Malformações do Desenvolvimento Cortical/genética , Malformações do Desenvolvimento Cortical/patologia , Criança , Pré-Escolar , Diferenciação Celular/genética , Proteínas Supressoras de Tumor
11.
Circulation ; 149(23): 1833-1851, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38586957

RESUMO

BACKGROUND: Adult mammalian cardiomyocytes have limited proliferative capacity, but in specifically induced contexts they traverse through cell-cycle reentry, offering the potential for heart regeneration. Endogenous cardiomyocyte proliferation is preceded by cardiomyocyte dedifferentiation (CMDD), wherein adult cardiomyocytes revert to a less matured state that is distinct from the classical myocardial fetal stress gene response associated with heart failure. However, very little is known about CMDD as a defined cardiomyocyte cell state in transition. METHODS: Here, we leveraged 2 models of in vitro cultured adult mouse cardiomyocytes and in vivo adeno-associated virus serotype 9 cardiomyocyte-targeted delivery of reprogramming factors (Oct4, Sox2, Klf4, and Myc) in adult mice to study CMDD. We profiled their transcriptomes using RNA sequencing, in combination with multiple published data sets, with the aim of identifying a common denominator for tracking CMDD. RESULTS: RNA sequencing and integrated analysis identified Asparagine Synthetase (Asns) as a unique molecular marker gene well correlated with CMDD, required for increased asparagine and also for distinct fluxes in other amino acids. Although Asns overexpression in Oct4, Sox2, Klf4, and Myc cardiomyocytes augmented hallmarks of CMDD, Asns deficiency led to defective regeneration in the neonatal mouse myocardial infarction model, increased cell death of cultured adult cardiomyocytes, and reduced cell cycle in Oct4, Sox2, Klf4, and Myc cardiomyocytes, at least in part through disrupting the mammalian target of rapamycin complex 1 pathway. CONCLUSIONS: We discovered a novel gene Asns as both a molecular marker and an essential mediator, marking a distinct threshold that appears in common for at least 4 models of CMDD, and revealing an Asns/mammalian target of rapamycin complex 1 axis dependency for dedifferentiating cardiomyocytes. Further study will be needed to extrapolate and assess its relevance to other cell state transitions as well as in heart regeneration.


Assuntos
Aspartato-Amônia Ligase , Desdiferenciação Celular , Fator 4 Semelhante a Kruppel , Miócitos Cardíacos , Animais , Camundongos , Aspartato-Amônia Ligase/genética , Aspartato-Amônia Ligase/metabolismo , Células Cultivadas , Miócitos Cardíacos/metabolismo , Carbono-Nitrogênio Ligases com Glutamina como Doadora de N-Amida/genética , Carbono-Nitrogênio Ligases com Glutamina como Doadora de N-Amida/metabolismo
12.
Electrophoresis ; 45(17-18): 1555-1561, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38517249

RESUMO

The analysis of cell electrophysiology for pathogenic samples at BSL3 can be problematic. It is virtually impossible to isolate infected from uninfected without a label, for example green fluorescent protein, which can potentially alter the cell electrical properties. Furthermore, the measurement of highly pathogenic organisms often requires equipment dedicated only for use with these organisms due to safety considerations. To address this, we have used dielectrophoresis to study the electrical properties of the human THP-1 cell line and monocyte-derived macrophages before and after infection with non-labelled Mycobacterium tuberculosis. Infection with these highly pathogenic bacilli resulted in changes including a raised surface conductance (associated with reduced zeta potential) and increased capacitance, suggesting an increase in surface roughness. We have also investigated the effect of fixation on THP-1 cells as a means to enable study on fixed samples in BSL1 or 2 laboratories, which suggests that the properties of these cells are largely unaffected by the fixation process. This advance results in a novel technique enabling the isolation of infected and non-infected cells in a sample without labelling.


Assuntos
Macrófagos , Mycobacterium tuberculosis , Humanos , Macrófagos/microbiologia , Células THP-1 , Eletroforese/métodos
13.
Brachytherapy ; 23(3): 321-328, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38514368

RESUMO

PURPOSE: To present the outcome and toxicity results of a prospective trial of 21 Gy single fraction high-dose-rate (HDR) brachytherapy for men with low- or intermediate-risk prostate cancer. METHODS AND MATERIALS: Patients were treated according to an IRB-approved prospective study of single fraction HDR brachytherapy. Eligible patients had low- or intermediate-risk prostate cancer with tumor stage ≤ T2b, PSA ≤ 15, and Gleason score ≤ 7. Patients underwent trans-rectal ultrasound-guided trans-perineal implant of the prostate followed by single fraction HDR brachytherapy to a dose of 21 Gy. The primary endpoint was grade ≥ 2 urinary/GI toxicity rates. RESULTS: Twenty-six patients were enrolled with a median follow up of 5.1 years and median age of 64 years. 88.5% of patients had T1 disease, 15.4% had Gleason score 6 (84.6% Gleason 7), and median pre-treatment PSA was 5.0 ng/mL. Acute and chronic grade ≥ 2 urinary toxicity rates were 38.5% and 38.5%, respectively. There were no grade ≥ 2 acute or chronic GI toxicities. Six (23.1%) patients experienced biochemical failure, six (23.1%) patients experienced radiographic local failure, and five (19.2%) patients had biopsy-proven local failure. No patients developed regional lymph node recurrence or distant metastasis. 5-year overall survival and cause-specific survival were 96.2% and 100%, respectively. CONCLUSIONS: 21 Gy single fraction HDR brachytherapy was associated with modestly higher-than-anticipated chronic urinary toxicity, as well as high biochemical and local failure rates. The results from this prospective pilot study do not support the use of this regimen in standard clinical practice.


Assuntos
Braquiterapia , Neoplasias da Próstata , Dosagem Radioterapêutica , Humanos , Masculino , Braquiterapia/métodos , Braquiterapia/efeitos adversos , Neoplasias da Próstata/radioterapia , Pessoa de Meia-Idade , Projetos Piloto , Idoso , Estudos Prospectivos , Resultado do Tratamento , Fracionamento da Dose de Radiação , Seguimentos
14.
Wound Repair Regen ; 32(4): 437-444, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38516794

RESUMO

Treatment of calcaneal fractures in patients with diabetes mellitus (DM) is challenging. The purpose of this study was to compare post-operative outcomes after open reduction and internal fixation (ORIF) for calcaneus fracture in patients with complicated DM, uncomplicated DM, and patients without DM. A commercially available de-identified database was queried for all calcaneus fracture diagnoses undergoing ORIF from 2010 to 2021. The patients were separated into three groups for analysis: patients without DM (10,951, 82.6%), uncomplicated DM (1,500, 11.3%) and complicated DM (802, 6.1%). At 1 year, post-operative adverse events were assessed among the three groups. The odds of adverse event(s) for each group were compared between the three groups with and without characteristic matching. In the unmatched cohorts, patients with complicated DM, when compared with patients without DM and patients with uncomplicated DM, had significantly higher rates of all adverse events with exception of DVT. Rates of CNA were significantly higher in patients with complicated DM compared with no DM (OR 107.7 (CI 24.83-467.6) p < 0.0001) and uncomplicated DM (OR 44.26 (CI 3.86-507.93) p = 0.0002). After matching, non-union, AKI, sepsis, surgical site infection, and wound disruption were higher in patients with complicated DM compared with patients without DM. There were no significant differences in the three groups with regard to reoperation, DVT, MI, pneumonia, or below the knee amputation. Patients with DM who underwent ORIF for calcaneus fracture experienced higher rates of post-operative adverse events compared with those patients without DM.


Assuntos
Calcâneo , Fixação Interna de Fraturas , Fraturas Ósseas , Redução Aberta , Humanos , Calcâneo/lesões , Calcâneo/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Fraturas Ósseas/cirurgia , Adulto , Idoso , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia , Bases de Dados Factuais , Estudos Retrospectivos , Diabetes Mellitus/epidemiologia , Complicações do Diabetes
15.
Lancet Gastroenterol Hepatol ; 9(5): 415-427, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38402895

RESUMO

BACKGROUND: Management strategies and clinical outcomes vary substantially in patients newly diagnosed with Crohn's disease. We evaluated the use of a putative prognostic biomarker to guide therapy by assessing outcomes in patients randomised to either top-down (ie, early combined immunosuppression with infliximab and immunomodulator) or accelerated step-up (conventional) treatment strategies. METHODS: PROFILE (PRedicting Outcomes For Crohn's disease using a moLecular biomarker) was a multicentre, open-label, biomarker-stratified, randomised controlled trial that enrolled adults with newly diagnosed active Crohn's disease (Harvey-Bradshaw Index ≥7, either elevated C-reactive protein or faecal calprotectin or both, and endoscopic evidence of active inflammation). Potential participants had blood drawn to be tested for a prognostic biomarker derived from T-cell transcriptional signatures (PredictSURE-IBD assay). Following testing, patients were randomly assigned, via a secure online platform, to top-down or accelerated step-up treatment stratified by biomarker subgroup (IBDhi or IBDlo), endoscopic inflammation (mild, moderate, or severe), and extent (colonic or other). Blinding to biomarker status was maintained throughout the trial. The primary endpoint was sustained steroid-free and surgery-free remission to week 48. Remission was defined by a composite of symptoms and inflammatory markers at all visits. Flare required active symptoms (HBI ≥5) plus raised inflammatory markers (CRP >upper limit of normal or faecal calprotectin ≥200 µg/g, or both), while remission was the converse-ie, quiescent symptoms (HBI <5) or resolved inflammatory markers (both CRP ≤ the upper limit of normal and calprotectin <200 µg/g) or both. Analyses were done in the full analysis (intention-to-treat) population. The trial has completed and is registered (ISRCTN11808228). FINDINGS: Between Dec 29, 2017, and Jan 5, 2022, 386 patients (mean age 33·6 years [SD 13·2]; 179 [46%] female, 207 [54%] male) were randomised: 193 to the top-down group and 193 to the accelerated step-up group. Median time from diagnosis to trial enrolment was 12 days (range 0-191). Primary outcome data were available for 379 participants (189 in the top-down group; 190 in the accelerated step-up group). There was no biomarker-treatment interaction effect (absolute difference 1 percentage points, 95% CI -15 to 15; p=0·944). Sustained steroid-free and surgery-free remission was significantly more frequent in the top-down group than in the accelerated step-up group (149 [79%] of 189 patients vs 29 [15%] of 190 patients, absolute difference 64 percentage points, 95% CI 57 to 72; p<0·0001). There were fewer adverse events (including disease flares) and serious adverse events in the top-down group than in the accelerated step-up group (adverse events: 168 vs 315; serious adverse events: 15 vs 42), with fewer complications requiring abdominal surgery (one vs ten) and no difference in serious infections (three vs eight). INTERPRETATION: Top-down treatment with combination infliximab plus immunomodulator achieved substantially better outcomes at 1 year than accelerated step-up treatment. The biomarker did not show clinical utility. Top-down treatment should be considered standard of care for patients with newly diagnosed active Crohn's disease. FUNDING: Wellcome and PredictImmune Ltd.


Assuntos
Doença de Crohn , Adulto , Humanos , Masculino , Feminino , Doença de Crohn/diagnóstico , Doença de Crohn/tratamento farmacológico , Doença de Crohn/complicações , Infliximab/uso terapêutico , Azatioprina/uso terapêutico , Biomarcadores , Fatores Imunológicos/uso terapêutico , Inflamação , Complexo Antígeno L1 Leucocitário
16.
Oncologist ; 29(3): 270-e413, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38325328

RESUMO

BACKGROUND: Combination checkpoint inhibition therapy with yttrium-90 (Y90) radioembolization represents an emerging area of interest in the treatment of advanced hepatocellular carcinoma (HCC). HCRN GI15-225 is an open-label, single-arm multicenter, pilot study (NCT03099564). METHODS: Eligible patients had poor prognosis, localized HCC defined as having portal vein thrombus, multifocal disease, and/or diffuse disease that were not eligible for liver transplant or surgical resection. Patients received pembrolizumab 200 mg intravenously every 3 weeks in conjunction with glass yttrium-90 (Y90) radioembolization TheraSphere. Primary endpoint was 6-month progression-free survival (PFS6) per RECIST 1.1. Secondary endpoints included time to progression (TTP), objective response rate (ORR), overall survival (OS), and safety/tolerability. RESULTS: Between October 23, 2017 and November 24, 2020, 29 patients were enrolled: 2 were excluded per protocol. Fifteen of the remaining 27 patients were free of progression at 6 months (55.6%; 95% CI, 35.3-74.5) with median PFS 9.95 months (95% CI, 4.14-15.24) and OS 27.30 months (95% CI, 10.15-39.52). One patient was not evaluable for response due to death; among the remaining 26 patients, ORR was 30.8% (95% CI, 14.3-51.8) and DCR was 84.6% (95% CI, 65.1-95.6). CONCLUSION: In patients with localized, poor prognosis HCC, pembrolizumab in addition to glass Y90 radioembolization demonstrated promising efficacy and safety consistent with prior observations (ClinicalTrials.gov Identifier: NCT03099564; IRB Approved: 16-3255 approved July 12, 2016).


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma Hepatocelular , Neoplasias Hepáticas , Radioisótopos de Ítrio , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/radioterapia , Projetos Piloto , Intervalo Livre de Progressão , Resultado do Tratamento
17.
J Pediatr Surg ; 59(1): 103-108, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37858393

RESUMO

BACKGROUND: Children with end-stage lung disease are commonly managed with extracorporeal life support (ECLS) as a bridge to lung transplantation. A pumpless artificial lung (MLung) is a portable alternative to ECLS and it allows for ambulation. Both ECLS and pumpless artificial lungs require systemic anticoagulation which is associated with hemorrhagic complications. We tested the MLung with a novel Nitric Oxide (NO) Surface Anticoagulation (NOSA) system, to provide local anticoagulation for 72 h of support in a pediatric-size ovine model. METHODS: Four mini sheep underwent thoracotomy and cannulation of the pulmonary artery (inflow) and left atrium (outflow), recovered and were monitored for 72hr. The circuit tubing and connectors were coated with the combination of an NO donor (diazeniumdiolated dibutylhexanediamine; DBHD-N2O2) and argatroban. The animals were connected to the MLung and 100 ppm of NO was added to the sweep gas. Systemic hemodynamics, blood chemistry, blood gases, and methemoglobin were collected. RESULTS: Mean device flow was 836 ± 121 mL/min. Device outlet saturation was 97 ± 4%. Pressure drop across the lung was 3.5 ± 1.5 mmHg and resistance was 4.3 ± 1.7 mmHg/L/min. Activated clotting time averaged 170 ± 45s. Methemoglobin was 2.9 ± 0.8%. Platelets declined from 590 ± 101 at baseline to 160 ± 90 at 72 h. NO flux (x10-10 mol/min/cm2) of the NOSA circuit averaged 2.8 ± 0.6 (before study) and 1.9 ± 0.1 (72 h) and across the MLung 18 ± 3 NO flux was delivered. CONCLUSION: The MLung is a more portable form of ECLS that demonstrates effective gas exchange for 72 h without hemodynamic changes. Additionally, the NOSA system successfully maintained local anticoagulation without evidence of systemic effects.


Assuntos
Oxigenação por Membrana Extracorpórea , Óxido Nítrico , Animais , Humanos , Ovinos , Criança , Metemoglobina , Pulmão , Hemodinâmica , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico
18.
Acad Radiol ; 31(2): 448-456, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37567818

RESUMO

RATIONALE AND OBJECTIVES: Methods are needed to improve the detection of hepatic metastases. Errors occur in both lesion detection (search) and decisions of benign versus malignant (classification). Our purpose was to evaluate a training program to reduce search errors and classification errors in the detection of hepatic metastases in contrast-enhanced abdominal computed tomography (CT). MATERIALS AND METHODS: After Institutional Review Board approval, we conducted a single-group prospective pretest-posttest study. Pretest and posttest were identical and consisted of interpreting 40 contrast-enhanced abdominal CT exams containing 91 liver metastases under eye tracking. Between pretest and posttest, readers completed search training with eye-tracker feedback and coaching to increase interpretation time, use liver windows, and use coronal reformations. They also completed classification training with part-task practice, rating lesions as benign or malignant. The primary outcome was metastases missed due to search errors (<2 seconds gaze under eye tracker) and classification errors (>2 seconds). Jackknife free-response receiver operator characteristic (JAFROC) analysis was also conducted. RESULTS: A total of 31 radiologist readers (8 abdominal subspecialists, 8 nonabdominal subspecialists, 15 senior residents/fellows) participated. Search errors were reduced (pretest 11%, posttest 8%, difference 3% [95% confidence interval, 0.3%-5.1%], P = .01), but there was no difference in classification errors (difference 0%, P = .97) or in JAFROC figure of merit (difference -0.01, P = .36). In subgroup analysis, abdominal subspecialists demonstrated no evidence of change. CONCLUSION: Targeted training reduced search errors but not classification errors for the detection of hepatic metastases at contrast-enhanced abdominal CT. Improvements were not seen in all subgroups.


Assuntos
Neoplasias Hepáticas , Tomografia Computadorizada por Raios X , Humanos , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos , Neoplasias Hepáticas/patologia , Meios de Contraste
19.
J Am Coll Radiol ; 21(2): 295-308, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37922972

RESUMO

OBJECTIVE: To identify independent predictors of all-cause and cancer-specific mortality after ablation or surgical resection (SR) for small hepatocellular carcinomas (HCCs), after adjusting for key confounders. METHODS: Using Surveillance, Epidemiology, and End Results Program-Medicare, HCCs less than 5 cm treated with ablation or SR in 2009 to 2016 (n = 956) were identified. Univariate and multivariable Cox regression models for all-cause and cancer-specific mortality were performed including demographics, clinical factors (tumor size, medical comorbidities, and liver disease factors), social determinants of health, and treatment characteristics. We also determined the most influential predictors of survival using a random forest analysis. RESULTS: Larger tumor size (3-5 cm) is predictive of all-cause (hazard ratio [HR] 1.31, P = .002) and cancer-specific mortality (HR 1.59, P < .001). Furthermore, chronic kidney disease is predictive of all-cause mortality (HR 1.43, P = .013), though it is not predictive of cancer-specific death. Multiple liver disease factors are predictive of all-cause and cancer-specific mortality including portal hypertension and esophageal varices (HRs > 1, P < .05). Though Asian race is protective in univariate models, in fully adjusted, multivariable models, Asian race is not a significant protective factor. Likewise, other social determinants of health are not significantly predictive of all-cause or cancer-specific mortality. Finally, treatment with SR, in later procedure years or at high-volume centers, is protective for all-cause and cancer-specific mortality. In machine learning models, year procedure was performed, ascites, portal hypertension, and treatment choice were the most influential factors. DISCUSSION: Treatment characteristics, liver disease factors, and tumor size are more important predictors of all-cause and cancer-specific death than social determinants of health for small HCCs.


Assuntos
Carcinoma Hepatocelular , Hipertensão Portal , Neoplasias Hepáticas , Idoso , Humanos , Estados Unidos/epidemiologia , Programa de SEER , Estudos Retrospectivos , Medicare , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/cirurgia , Resultado do Tratamento
20.
J Exp Bot ; 75(3): 947-961, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37891008

RESUMO

The production of ATP and NADPH by the light reactions of photosynthesis and their consumption by the Calvin-Benson-Bassham (CBB) cycle and other downstream metabolic reactions requires careful regulation. Environmental shifts perturb this balance, leading to photo-oxidative stress and losses in CO2 assimilation. Imbalances in the production and consumption of ATP and NADPH manifest themselves as transient instability in the chlorophyll fluorescence, P700, electrochromic shift, and CO2 uptake signals recorded on leaves. These oscillations can be induced in wild-type plants by sudden shifts in CO2 concentration or light intensity; however, mutants exhibiting increased oscillatory behaviour have yet to be reported. This has precluded an understanding of the regulatory mechanisms employed by plants to suppress oscillations. Here we show that the Arabidopsis pgr5 mutant, which is deficient in Proton Gradient Regulation 5 (PGR5)-dependent cyclic electron transfer (CET), exhibits increased oscillatory behaviour. In contrast, mutants lacking the NADH-dehydrogenase-like-dependent CET are largely unaffected. The absence of oscillations in the hope2 mutant which, like pgr5, lacks photosynthetic control and exhibits high ATP synthase conductivity, ruled out loss of these photoprotective mechanisms as causes. Instead, we observed slower formation of the proton motive force and, by inference, ATP synthesis in pgr5 following environmental perturbation, leading to the transient reduction of the electron transfer chain and photosynthetic oscillations. PGR5-dependent CET therefore plays a major role in damping the effect of environmental perturbations on photosynthesis to avoid losses in CO2 fixation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Complexo de Proteínas do Centro de Reação Fotossintética , Prótons , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Dióxido de Carbono/metabolismo , NADP/metabolismo , Complexo de Proteína do Fotossistema I/metabolismo , Fotossíntese/fisiologia , Transporte de Elétrons , Arabidopsis/metabolismo , Luz , Trifosfato de Adenosina/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA