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1.
Spine Deform ; 2022 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35000131

RESUMO

PURPOSE: Although scoliosis and kyphosis have been associated with Williams Syndrome (WS), no previous literature has reported on surgical treatment for early onset scoliosis (EOS) in WS. The aim of this case series is to report on the outcomes of spine deformity surgery in patients with EOS and WS and any perioperative anesthetic or cardiovascular complications. METHODS: One multicenter database was queried for all patients with WS who underwent growth-friendly (GF) treatment before age 12 between 2000 and 2017. Demographics, surgical, and growth-friendly data were queried. Radiographs were measured for curve magnitude, T1-T12 length, and T1-S1 length. RESULTS: Seven patients were analyzed (3 males, 4 females). Patients were at a median age of 2.8 years at initial surgery with median follow-up 3.6 years (range 2.0-12 years) after index surgery. The initial surgical treatments were as follows: 2 traditional growing rods (TGR), 2 magnetically controlled growing rods (MCGR), and 3 vertical expandable prosthetic titanium ribs (VEPTR). The median duration of growth-friendly treatment was 5.0 years (range, 2.6-10.4 years) with a median number of 9 device lengthenings. The median improvement in coronal curve magnitude from preoperative to most recent follow-up was 19° (range, 54°-9°). Three patients have completed GF treatment: one underwent definitive fusion, and two are under observation with apparent spontaneous fusion and retain the original GF implants. No peri-operative anesthetic or cardiovascular complications occurred. CONCLUSIONS: Few studies have reported on surgical outcomes in WS patients with EOS. In this case series, 6/7 patients experienced curve improvement with growth-friendly spine instrumentation. This study suggests that growth-friendly instrumentation for severe EOS in WS can be used for control of spinal deformity while allowing for further growth. Associated complications were typical of distraction-based EOS surgical treatment. There were 62 total procedures with general anesthesia, but no perioperative cardiac complications occurred.

2.
J Patient Exp ; 8: 23743735211064141, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34901410

RESUMO

Background: Shared Decision-Making (SDM) is an inclusive approach where patients and providers work in partnership to make health care decisions that are grounded in clinical best practice and align with patient preferences and values. Despite a growing recognition that SDM can lead to improved outcomes and reductions in unnecessary health investigations, tensions exist between patient agency and a historically paternalistic model of health care. As an evolving ideology, the Research Team sought to better understand the current state, challenges, and implementation opportunities of SDM practices across the health system. Methods: This study used a cross-sectional quality improvement design utilizing semistructured interviews to gather information from focus group participants. Five open-ended, qualitative questions were used to generate discussion on the perceptions of SDM and its role in clinical appropriateness in a variety of clinical contexts in our health system. A total of 12 focus groups (n = 95 participants) representative of patients and families, leaders, physicians, and frontline clinicians were engaged in the study. Results: Through a consensus-based approach, study results identified 4 recommendations based on 4 themes: Time, Communication, System Design, and Clinical Appropriateness. Conclusion: There are no easy solutions to the challenges of enabling SDM; however, success will be dependent upon recognizing the importance of patient agency, while maintaining an inclusive and continuous stakeholder engagement with both patients and providers. Implementation of the 4 recommendations at the organizational level highlighted in this study can serve as a road map for other health care institutions and will require a gradual approach to transform the general principles of SDM into tangible solutions to meet the emerging needs at both the local and system level.

3.
Cancer Res ; 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737214

RESUMO

ECT2 is an activator of RHO GTPases that is essential for cytokinesis. Additionally, ECT2 was identified as an oncoprotein when expressed ectopically in NIH/3T3 fibroblasts. However, oncogenic activation of ECT2 resulted from N-terminal truncation, and such truncated ECT2 proteins have not been found in cancer patients. In this study, we observed elevated expression of full-length ECT2 protein in preneoplastic colon adenomas, driven by increased ECT2 mRNA abundance and associated with APC tumor suppressor loss. Elevated ECT2 levels were detected in the cytoplasm and nucleus of colorectal cancer (CRC) tissue, suggesting cytoplasmic mislocalization as one mechanism of early oncogenic ECT2 activation. Importantly, elevated nuclear ECT2 correlated with poorly differentiated tumors, and a low cytoplasmic:nuclear ratio of ECT2 protein correlated with poor patient survival, suggesting that nuclear and cytoplasmic ECT2 play distinct roles in CRC. Depletion of ECT2 reduced anchorage-independent cancer cell growth and invasion independent of its function in cytokinesis, and loss of Ect2 extended survival in a KrasG12D Apc-null colon cancer mouse model. Expression of ECT2 variants with impaired nuclear localization or guanine nucleotide exchange catalytic activity failed to restore cancer cell growth or invasion, indicating that active, nuclear ECT2 is required to support tumor progression. Nuclear ECT2 promoted ribosomal DNA transcription and ribosome biogenesis in CRC. These results support a driver role for both cytoplasmic and nuclear ECT2 overexpression in CRC and emphasize the critical role of precise subcellular localization in dictating ECT2 function in neoplastic cells.

4.
J Pediatr Orthop ; 41(10): 591-596, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34516471

RESUMO

BACKGROUND: Accurate pedicle screw placement is critical to surgically correct pediatric high-grade spondylolisthesis (HGS). The recent advent of robotics coupled with computer-assisted navigation (RAN) may represent a novel option to improve surgical outcomes of HGS, secondary to enhanced pedicle screw placement safety. This series presents the HGS-RAN technique adopted by our site, describing its surgical outcomes and feasibility. METHODS: Consecutive patients with a diagnosis of HGS (Meyerding grade III to V), operated on using RAN from 2019 to 2020 at a single-center were reviewed. Demographics, screw accuracy, sagittal L5-S1 parameters, complications, and perioperative outcomes were described. All patients were treated with instrumentation, decompression, posterior lumbar interbody fusion, and reduction. Robotic time included anatomic registration to end of screw placement. Screw accuracy-defined as a screw placed safely within the planned intrapedicular trajectory-was characterized by the Gertzbein-Robbins system for patients with additional 3-dimensional imaging. RESULTS: Ten HGS patients, with an average age of 13.7 years old, were included in the series. All 62 screws were placed without neurological deficit or complication. Seven patients had additional 3-dimensional imaging to assess screw accuracy (42 of 62 screws). One hundred percent of screws were placed safely with no pedicle breaches (Gertzbein-Robbins-grade A). Thirty screws (48%) were placed through separate incisions that were percutaneous/transmuscular and 32 screws (52%) were inserted through the main incision. There were statistically significant improvements in L5 slippage (P=0.002) and lumbosacral angle (P=0.002), reflecting successful HGS correction. The total median operative time was 324 minutes with the robotic usage time consuming a median of 72 minutes. Median estimated blood loss was 150 mL, and length-of-stay was a median 3 days. CONCLUSIONS: This case-series demonstrates that RAN represents a viable option for HGS repair, indicated by high screw placement accuracy, safety, and L5-S1 slippage correction. Surgeons looking to adopt an emerging technique to enhance safety and correction of pediatric HGS should consider the RAN platform. LEVEL OF EVIDENCE: Level IV-therapeutic study.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Espondilolistese , Adolescente , Criança , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Região Lombossacral , Espondilolistese/diagnóstico por imagem , Espondilolistese/cirurgia
6.
J Pediatr Orthop ; 41(9): e722-e726, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34334697

RESUMO

BACKGROUND: High-volume centers for idiopathic scoliosis (IS) have difficulty in scheduling posterior spinal fusions (PSFs) due to operating room availability, particularly during school vacation. A solution is for 1 surgeon to perform 2 PSF cases back-to-back. This study aims to compare morning and afternoon PSF cases performed by the same surgeon for perioperative outcomes. METHODS: A retrospective review of PSF cases for IS that occurred on the same day as another PSF by the same surgeon between January 2013 and December 2019 was conducted. Perioperative outcomes included surgical time, estimated blood loss, length of stay, and inpatient opioid consumption normalized by the patient's weight. Postoperative outcomes included complications, revision rate, curve correction, and patient-reported outcomes using the Scoliosis Research Society-30. RESULTS: A total of 95 patients (87% female), mean age 15.6 years, were analyzed, with 48 morning cases and 47 afternoon cases. The median follow-up was 1.9 years (range: 0.3 to 6.1 y). Tests for equivalency determined equivalence in median anesthesia and mean surgical duration (P=0.05). The groups had similar initial curve correction (P=0.43) and rate of complications at 90 days postoperative (2 in each group for a total of 4 complications). No significant differences were seen between Scoliosis Research Society-30 scores at 6 months or in those who have reached 2 years postoperative. CONCLUSIONS: Little literature exists on the safety of a surgeon performing 2 PSF cases in 1 day, particularly in regard to pain outcomes, 30- and 90-day complication rates, and quality of life measures. This study indicates that few differences in safety, pain, and quality of life outcomes may appear between morning and afternoon PSF cases. LEVEL OF EVIDENCE: Level II.


Assuntos
Escoliose , Fusão Vertebral , Adolescente , Feminino , Humanos , Masculino , Qualidade de Vida , Estudos Retrospectivos , Escoliose/cirurgia , Fusão Vertebral/efeitos adversos , Resultado do Tratamento
7.
J Pediatr Orthop ; 41(6): 379-384, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34096555

RESUMO

BACKGROUND: The prevalence of venous thromboembolism (VTE) may be increasing in children; however, scarce literature exists comparing incidence rates between pediatric orthopaedic patients and other pediatric patients. The purpose of this study was to compare the incidence, anatomic locations, and risk factors of VTEs between orthopaedic and nonorthopaedic pediatric related patients to determine if important differences exist. METHODS: Computed tomography and ultrasound data were reviewed for children (below 19 y old) with a diagnosed VTE between January 1, 2009 and December 31, 2016. Demographic and clinical data, including VTE anatomic location and risk factors, were recorded. Two major cohorts were identified: orthopaedic-related (ORTH) and nonorthopaedic-related (NORTH) VTEs. Incidence rates were estimated and risk factors were compared using χ2 testing. RESULTS: There were 373 children diagnosed with a VTE (average age 10.3 y) of a total of 810,097 treated as in-patients for an incidence rate of 4.60 per 10,000 cases (95% confidence interval=4.15 to 5.10 per 10,000 cases). The rate of ORTH VTEs (28 of 188,669 orthopaedic patients, 1.48 per 10,000 cases) was significantly lower than that of NORTH VTEs (345 of 621,428 nonorthopaedic patients, 5.55 per 10,000 cases; P<0.001). For the ORTH cohort, there was a significant difference in the proportion of deep vein thrombosis in the lower extremity (91%) compared with the upper extremity (9%) (P<0.001), while a more even distribution of NORTH deep vein thrombosis in the upper (50%) and lower (41%) extremities was appreciated. The primary risk factors for ORTH VTEs included surgery (93%; P<0.001), change in ambulatory status (61%; P<0.001), and trauma (18%; P<0.001), while the primary risk factors for NORTH VTEs included intravenous peripheral inserted central catheter/central line (61%; P<0.001) and cancer (27%; P=0.001). CONCLUSIONS: Pediatric ORTH VTEs have a significantly lower incidence rate and different primary risk factors than those of NORTH VTEs. This information is useful for health care providers when making decisions regarding risk and prophylaxis in pediatric patients with orthopaedic and nonorthopaedic conditions. LEVEL OF EVIDENCE: Level III.


Assuntos
Procedimentos Ortopédicos/estatística & dados numéricos , Tromboembolia Venosa/epidemiologia , Trombose Venosa/epidemiologia , Adolescente , Cateteres Venosos Centrais/estatística & dados numéricos , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Incidência , Extremidade Inferior , Masculino , Ortopedia/estatística & dados numéricos , Fatores de Risco , Extremidade Superior , Tromboembolia Venosa/diagnóstico por imagem , Caminhada , Ferimentos e Lesões/epidemiologia
8.
J Pediatr Orthop ; 41(6): e380-e385, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33782367

RESUMO

BACKGROUND: Recent focus on surgical site infections (SSIs) after posterior spine fusion (PSF) has lowered infection rates by standardizing perioperative antibiotic prophylaxis. However, efforts have neglected to detail antibiotic treatment of SSIs. Our aim was to document variability in antibiotic regimens prescribed for acute and latent SSIs following PSF in children with idiopathic, neuromuscular, and syndromic scoliosis. METHODS: This study included patients who developed a SSI after PSF for scoliosis at a pediatric tertiary care hospital between 2004 and 2019. Patients had to be 21 years or younger at surgery. Exclusion criteria included growing rods, staged surgery, and revision or removal before SSI diagnosis. Infection was classified as acute (within 90 d) or latent. Clinical resolution of SSI was measured by return to normal lab values. Each antibiotic was categorized as empiric or tailored. RESULTS: Eighty subjects were identified. The average age at fusion was 14.7 years and 40% of the cohort was male. Most diagnoses were neuromuscular (53%) or idiopathic (41%).Sixty-three percent of patients had an acute infection and 88% had a deep infection. The majority (54%) of subjects began on tailored antibiotic therapy versus empiric (46%). Patients with a neuromuscular diagnosis had 4.0 times the odds of receiving initial empiric treatment compared with patients with an idiopathic diagnosis, controlling for infection type and time (P=0.01). Ninety-two percent of patients with acute SSI retained implants at the time of infection and 76% retained them as of August 2020. In the latent cohort, 27% retained implants at infection and 17% retained them as of August 2020. CONCLUSIONS: Patients with acute infections were on antibiotics longer than patients with latent infections. Those with retained implants were on antibiotics longer than those who underwent removal. By providing averages of antibiotic duration and lab normalization, we hope to standardize regimens moving forward and develop SSI-reducing pathways encompassing low-risk patients. LEVEL OF EVIDENCE: Level III.


Assuntos
Antibacterianos/administração & dosagem , Escoliose/cirurgia , Fusão Vertebral/efeitos adversos , Infecção da Ferida Cirúrgica/tratamento farmacológico , Administração Intravenosa , Administração Oral , Adolescente , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Próteses e Implantes , Reinfecção , Infecção da Ferida Cirúrgica/etiologia , Adulto Jovem
9.
J Pediatr Urol ; 17(3): 290.e1-290.e7, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33622629

RESUMO

INTRODUCTION: Relative Energy Deficiency in Sport (RED-S) is a clinical syndrome that includes the many complex health and performance consequences of low energy availability (EA) in athletes, when there is insufficient caloric intake to meet exercise-related energy expenditure and to support basic physiologic functions. There is a high prevalence of urinary incontinence (UI) in female athletes and it is more common in female athletes than non-athletes. The objective of this study was to determine if low EA is associated with UI in a population of adolescent and young adult female athletes and to evaluate for an association between sport categories and UI. MATERIAL AND METHODS: 1000 nulliparous female patients, ages 15-30 years, presenting to a sports medicine subspecialty clinic, provided informed consent/assent to participate in a cross-sectional study involving a comprehensive survey, anthropomorphic measurements, and medical record review. Low EA was defined as meeting ≥1 criterion: self-reported history of eating disorder/disordered eating (ED/DE), and/or a high score on the Brief Eating Disorder in Athletes Questionnaire (BEDA-Q), and/or a high score on the Eating Disorder Screen for Primary Care (ESP). UI was assessed using questions adapted from the International Consultation on Incontinence-Urinary Incontinence Short Form (ICIQ-UI-SF), questions regarding timing of UI onset/duration, and a binary question regarding UI during sport activities. A total of 36 sport types were included in the survey and sub-divided into categories. RESULTS AND DISCUSSION: Of the 1000 female athletes surveyed, 165 (16.5%) reported a history of experiencing UI during athletic activities. ICIQ- UI-SF responses indicated that 14% (137/1000) of the cohort experienced slight incontinence, 4% (35/1000) moderate incontinence, and 2 athletes experienced severe incontinence. There was a significant difference between UI categories in age (p = 0.01), low EA (p < 0.001), and sport category (p < 0.001). Females who had low EA had twice the likelihood (OR = 1.97; 95% CI = 1.39 to 2.81; p < 0.001) of UI compared to those with adequate EA, controlling for sports category and menstrual dysfunction. Females who participated in high impact sports were 4.5 times more likely (OR = 4.47; 95% CI = 2.29 to 8.74; p < 0.001) to have had UI compared to females who participated in ball sports, controlling for EA and menstrual dysfunction. CONCLUSIONS: UI during athletic activities is a common problem among nulliparous adolescent and young adult female athletes, occurring in 16.5% of female athletes surveyed. UI was significantly associated with low EA across all sport categories. Sport type was significantly associated with UI, with the highest impact sport group demonstrating a higher prevalence and symptom severity compared to other sport categories.


Assuntos
Esportes , Incontinência Urinária , Adolescente , Adulto , Atletas , Estudos Transversais , Feminino , Humanos , Prevalência , Fatores de Risco , Inquéritos e Questionários , Incontinência Urinária/epidemiologia , Incontinência Urinária/etiologia , Adulto Jovem
10.
J Robot Surg ; 15(5): 687-693, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33094435

RESUMO

Pedicle screw fixation in pediatric spine surgery has become common practice given the fixation stability and improved curve correction. However, due to proximity to vital structures, accuracy is paramount. Literature has reported accuracy rates from 87.5 to 90% using traditional freehand techniques. This study presents our initial experience with pedicle screw placement using the newest generation of spinal robotics for treatment of pediatric spinal deformity. A cohort of patients, aged 8-21 years, undergoing spinal fusion surgery using robotic-assisted technology was reviewed. Diagnoses, Cobb angles, surgical time, robot time, number of screws placed, and complications were recorded. Accuracy of screw placement was assessed based on analysis of successful screw execution, evaluation screw position using intraoperative fluoroscopy and post-operative radiographs, and clinical evaluation. The average age was 14.5 years. Prevalent diagnoses included idiopathic (65%) and neuromuscular scoliosis (13%). Mean preoperative curve measured 66.8°. The median time for operation was 235 minutes with medians of 8 levels fused and 5 screws placed per patient. Of the 314 screws placed, we recorded a 98.7% accuracy rate. Lateral deviation was the most common cause of malpositioning. Post-operative plain films revealed no grossly misplaced screws. There were no perioperative neurologic deficits or malpositioned screws requiring reoperation. This is the first reported series of navigated spinal robotics used for pedicle screw placement in children. Our clinical success rate was 98.7% and there were no clinically relevant screw related complications. The study shows promising initial results of combined robotic-navigation techniques in pediatric patients.


Assuntos
Parafusos Pediculares , Procedimentos Cirúrgicos Robóticos , Escoliose , Fusão Vertebral , Cirurgia Assistida por Computador , Adolescente , Criança , Humanos , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/cirurgia
11.
Mol Ther Oncolytics ; 11: 20-38, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30306125

RESUMO

We generated two humanized interleukin-13 receptor α2 (IL-13Rα2) chimeric antigen receptors (CARs), Hu07BBz and Hu08BBz, that recognized human IL-13Rα2, but not IL-13Rα1. Hu08BBz also recognized canine IL-13Rα2. Both of these CAR T cell constructs demonstrated superior tumor inhibitory effects in a subcutaneous xenograft model of human glioma compared with a humanized EGFRvIII CAR T construct used in a recent phase 1 clinical trial (ClinicalTrials.gov: NCT02209376). The Hu08BBz demonstrated a 75% reduction in orthotopic tumor growth using low-dose CAR T cell infusion. Using combination therapy with immune checkpoint blockade, humanized IL-13Rα2 CAR T cells performed significantly better when combined with CTLA-4 blockade, and humanized EGFRvIII CAR T cells' efficacy was improved by PD-1 and TIM-3 blockade in the same mouse model, which was correlated with the levels of checkpoint molecule expression in co-cultures with the same tumor in vitro. Humanized IL-13Rα2 CAR T cells also demonstrated benefit from a self-secreted anti-CTLA-4 minibody in the same mouse model. In addition to a canine glioma cell line (J3T), canine osteosarcoma lung cancer and leukemia cell lines also express IL-13Rα2 and were recognized by Hu08BBz. Canine IL-13Rα2 CAR T cell was also generated and tested in vitro by co-culture with canine tumor cells and in vivo in an orthotopic model of canine glioma. Based on these results, we are designing a pre-clinical trial to evaluate the safety of canine IL-13Rα2 CAR T cells in dog with spontaneous IL-13Rα2-positive glioma, which will help to inform a human clinical trial design for glioblastoma using humanized scFv-based IL-13Rα2 targeting CAR T cells.

12.
Environ Monit Assess ; 190(6): 339, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29748723

RESUMO

Dam removal is an increasingly common river restoration option, yet some of the mechanisms leading to ecological changes remain unquantified. We assessed relationships between riffle structure and benthic macroinvertebrate and fish assemblages 2 years after a lowhead dam removal in Ohio, USA. Hydrogeomorphic, water-chemistry, and biotic surveys were conducted at seven study riffles at six time intervals from spring 2014 through summer 2015. The density and diversity of macroinvertebrates and fish were significantly different over time, largely as a function of season (lowest densities in early spring, greatest in summer). Macroinvertebrate, but not fish, assemblage composition was different by time but not riffle. Although hydrogeomorphic characteristics (e.g., streamflow velocity, substrate size) were linked to shifts in macroinvertebrates and fish, chemical water-quality parameters (e.g., dissolved oxygen, nutrient concentrations) were also implicated as potential biotic drivers. Our results indicate that riffle habitat development can be an important mechanism related to restoring sensitive species and biological diversity following dam removal.


Assuntos
Organismos Aquáticos/classificação , Biota , Monitoramento Ambiental/métodos , Peixes/classificação , Invertebrados/classificação , Rios , Animais , Organismos Aquáticos/isolamento & purificação , Biodiversidade , Ecossistema , Sedimentos Geológicos/análise , Ohio , Estações do Ano , Qualidade da Água
13.
Cell Rep ; 20(2): 427-438, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28700943

RESUMO

Activating mutations in the KRAS oncogene are highly prevalent in tumors, especially those of the colon, lung, and pancreas. To better understand the genetic dependencies that K-Ras mutant cells rely upon for their growth, we employed whole-genome CRISPR loss-of-function screens in two isogenic pairs of cell lines. Since loss of essential genes is uniformly toxic in CRISPR-based screens, we also developed a small hairpin RNA (shRNA) library targeting essential genes. These approaches uncovered a large set of proteins whose loss results in the selective reduction of K-Ras mutant cell growth. Pathway analysis revealed that many of these genes function in the mitochondria. For validation, we generated isogenic pairs of cell lines using CRISPR-based genome engineering, which confirmed the dependency of K-Ras mutant cells on these mitochondrial pathways. Finally, we found that mitochondrial inhibitors reduce the growth of K-Ras mutant tumors in vivo, aiding in the advancement of strategies to target K-Ras-driven malignancy.


Assuntos
Proliferação de Células/fisiologia , Genes ras/genética , Proteínas Proto-Oncogênicas/metabolismo , Animais , Linhagem Celular , Proliferação de Células/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Feminino , Células HCT116 , Humanos , Hidrazonas/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Minociclina/análogos & derivados , Minociclina/farmacologia , Mutação/genética , NADH Desidrogenase/genética , NADH Desidrogenase/metabolismo , Proteínas Proto-Oncogênicas/genética , Tigeciclina , Triazóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Blood ; 127(9): 1117-27, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26813675

RESUMO

Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy is highly promising but requires robust T-cell expansion and engraftment. A T-cell defect in chronic lymphocytic leukemia (CLL) due to disease and/or therapy impairs ex vivo expansion and response to CAR T cells. To evaluate the effect of ibrutinib treatment on the T-cell compartment in CLL as it relates to CAR T-cell generation, we examined the phenotype and function of T cells in a cohort of CLL patients during their course of treatment with ibrutinib. We found that ≥5 cycles of ibrutinib therapy improved the expansion of CD19-directed CAR T cells (CTL019), in association with decreased expression of the immunosuppressive molecule programmed cell death 1 on T cells and of CD200 on B-CLL cells. In support of these findings, we observed that 3 CLL patients who had been treated with ibrutinib for ≥1 year at the time of T-cell collection had improved ex vivo and in vivo CTL019 expansion, which correlated positively together and with clinical response. Lastly, we show that ibrutinib exposure does not impair CAR T-cell function in vitro but does improve CAR T-cell engraftment, tumor clearance, and survival in human xenograft models of resistant acute lymphocytic leukemia and CLL when administered concurrently. Our collective findings indicate that ibrutinib enhances CAR T-cell function and suggest that clinical trials with combination therapy are warranted. Our studies demonstrate that improved T-cell function may also contribute to the efficacy of ibrutinib in CLL. These trials were registered at www.clinicaltrials.gov as #NCT01747486, #NCT01105247, and #NCT01217749.


Assuntos
Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/imunologia , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia , Adenina/análogos & derivados , Administração Oral , Idoso , Animais , Antígenos CD/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citotoxicidade Imunológica/efeitos dos fármacos , Demografia , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Técnicas de Transferência de Genes , Humanos , Células K562 , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Piperidinas , Receptor de Morte Celular Programada 1/metabolismo , Pirazóis/administração & dosagem , Pirazóis/farmacologia , Pirimidinas/administração & dosagem , Pirimidinas/farmacologia , Linfócitos T/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento
15.
Genes Cancer ; 4(11-12): 460-75, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24386507

RESUMO

Ect2, a Rho guanine nucleotide exchange factor (RhoGEF), is atypical among RhoGEFs in its predominantly nuclear localization in interphase cells. One current model suggests that Ect2 mislocalization drives cellular transformation by promoting aberrant activation of cytoplasmic Rho family GTPase substrates. However, in ovarian cancers, where Ect2 is both amplified and overexpressed at the mRNA level, we observed that the protein is highly expressed and predominantly nuclear and that nuclear but not cytoplasmic Ect2 increases with advanced disease. Knockdown of Ect2 in ovarian cancer cell lines impaired their anchorage-independent growth without affecting their growth on plastic. Restoration of Ect2 expression rescued the anchorage-independent growth defect, but not if either the DH catalytic domain or the nuclear localization sequences of Ect2 were mutated. These results suggested a novel mechanism whereby Ect2 could drive transformation in ovarian cancer cells by acting as a RhoGEF specifically within the nucleus. Interestingly, Ect2 had an intrinsically distinct GTPase specificity profile in the nucleus versus the cytoplasm. Nuclear Ect2 bound preferentially to Rac1, while cytoplasmic Ect2 bound to RhoA but not Rac. Consistent with nuclear activation of endogenous Rac, Ect2 overexpression was sufficient to recruit Rac effectors to the nucleus, a process that required a functional Ect2 catalytic domain. Furthermore, expression of active nuclearly targeted Rac1 rescued the defect in transformed growth caused by Ect2 knockdown. Our work suggests a novel mechanism of Ect2-driven transformation, identifies subcellular localization as a regulator of GEF specificity, and implicates activation of nuclear Rac1 in cellular transformation.

16.
Cancer Immunol Immunother ; 60(7): 985-97, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21461886

RESUMO

Multiple myeloma is incurable with standard therapies but is susceptible to a T-cell-mediated graft versus myeloma effect after allogeneic stem cell transplantation. We sought to identify myeloma-specific antigens that might be used for T-cell immunotherapy of myeloma. MAGE-C1 (CT-7) is a cancer-testis antigen that is expressed by tumor cells in >70% of myeloma patients and elicits a humoral response in up to 93% of patients with CT-7(+) myeloma. No CD8(+) T-cell epitopes have been described for CT-7, so we used a combination of reverse immunology and immunization of HLA-A2 transgenic mice with a novel cell-based vaccine to identify three immunogenic epitopes of CT-7 that are recognized by human CD8(+) T-cells. CT-7-specific T-cells recognizing two of these peptides are able to recognize myeloma cells as well as CT-7 gene-transduced tumor cells, demonstrating that these epitopes are naturally processed and presented by tumor cells. This is the first report of the identification of immunogenic CD8(+) T-cell epitopes of MAGE-C1 (CT-7), which is the most commonly expressed cancer-testis antigen found in myeloma, and these epitopes may be promising candidate targets for vaccination or T-cell therapy of myeloma or other CT-7(+) malignancies.


Assuntos
Antígenos de Neoplasias/imunologia , Epitopos de Linfócito T/imunologia , Imunoterapia , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/terapia , Proteínas de Neoplasias/imunologia , Animais , Apresentação do Antígeno , Antígenos de Neoplasias/genética , Células Dendríticas/imunologia , Citometria de Fluxo , Antígeno HLA-A2/fisiologia , Humanos , Interferon gama/metabolismo , Camundongos , Camundongos Transgênicos , Mieloma Múltiplo/genética , Proteínas de Neoplasias/genética , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Células Tumorais Cultivadas , Vacinação
17.
Genes Cancer ; 2(10): 932-42, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22701760

RESUMO

Ect2 is a member of the human Dbl family of guanine nucleotide exchange factors (RhoGEFs) that serve as activators of Rho family small GTPases. Although Ect2 is one of at least 25 RhoGEFs that can activate the RhoA small GTPase, cell culture studies using established cell lines determined that Ect2 is essential for mammalian cell cytokinesis and proliferation. To address the function of Ect2 in normal mammalian development, we performed gene targeting to generate Ect2 knockout mice. The heterozygous Ect2(+/-) mice showed normal development and life span, indicating that Ect2 haplodeficiency was not deleterious for development or growth. In contrast, Ect2(-/-) embryos were not found at birth or postimplantation stages. Ect2(-/-) blastocysts were recovered at embryonic day 3.5 but did not give rise to viable outgrowths in culture, indicating that Ect2 is required for peri-implantation development. To further assess the importance of Ect2 in normal cell physiology, we isolated primary fibroblasts from Ect2(fl/fl) embryos (MEFs) and ablated Ect2 using adenoviral delivery of Cre recombinase. We observed a significant increase in multinucleated cells and accumulation of cells in G2/M phase, consistent with a role for Ect2 in cytokinesis. Ect2 deficiency also caused enlargement of the cytoplasm and impaired cell migration. Finally, although Ect2-dependent activation of RhoA has been implicated in cytokinesis, Ect2 can also activate Rac1 and Cdc42 to cause growth transformation. Surprisingly, ectopic expression of constitutively activated RhoA, Rac1, or Cdc42, known substrates of Ect2, failed to phenocopy Ect2 and did not rescue the defect in cytokinesis caused by loss of Ect2. In summary, our results establish the unique role of Ect2 in development and normal cell proliferation.

18.
Tuberculosis (Edinb) ; 89(4): 294-303, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19556165

RESUMO

In mice, and possibly in humans, nitric oxide (NO) is an important host-defense molecule against Mycobacterium tuberculosis. Inducible nitric oxide synthase (iNOS) and NO are upregulated in murine macrophages stimulated with interferon-gamma (IFNgamma) and mannose-capped lipoarabinomannan (ManLAM), a major lipoglycan in the cell wall of M. tuberculosis. Interleukin-4 (IL-4) can inhibit NO expression and may impair host immune response to M. tuberculosis. Therefore, we sought to determine the mechanism by which IL-4 inhibits IFNgamma+ManLAM-induced NO production. Since l-arginine is the substrate for both iNOS and arginase, and IL-4 increases arginase activity by inducing its production, a plausible mechanism of IL-4 inhibition of NO expression is via depletion of l-arginine through increased arginase activity. Herein, we show that IL-4 inhibited iNOS gene expression at the transcriptional level, suggesting an inhibitory mechanism that is independent of the competition for l-arginine between iNOS and arginase. Furthermore, pharmacologic inhibition of IL-4-induced arginase activity did not abrogate IL-4 inhibition of IFNgamma+ManLAM-induced NO expression. Instead, inhibition by IL-4 was mediated principally by the ability of IL-4 to inhibit the production of IFNgamma-induced interferon-gamma response factor-1 (IRF-1) protein, a critically important transcriptional element that enhances expression of IFNgamma-inducible genes such as iNOS.


Assuntos
Interferon gama/farmacologia , Interleucina-4/farmacologia , Lipopolissacarídeos/farmacologia , Óxido Nítrico/biossíntese , Animais , Arginase/metabolismo , Arginina/metabolismo , Western Blotting , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Expressão Gênica/efeitos dos fármacos , Humanos , Fator Regulador 1 de Interferon/metabolismo , Interferon gama/metabolismo , Interleucina-18/metabolismo , Lipopolissacarídeos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/imunologia , Óxido Nítrico/genética , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Regiões Promotoras Genéticas/fisiologia , RNA Mensageiro/metabolismo , Fator de Transcrição STAT6/metabolismo
19.
Am J Respir Cell Mol Biol ; 41(2): 170-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19097985

RESUMO

Mycobacterium abscessus is a rapidly growing environmental mycobacterium that can cause severe skin, soft tissue, and lung infections. M. abscessus grows inside macrophages, and these cells release a vast number of proinflammatory cytokines in response to infections. The metalloporphyrin, MnTE-2-PyP, is a broad antioxidant that reduces inflammatory cell signaling. Macrophage-like THP-1 cells were infected with M. abscessus in the presence or absence of MnTE-2-PyP. MnTE-2-PyP significantly decreased, in a dose-dependent manner, the number of M. abscessus organisms recovered from infected THP-1 cells 4 and 8 days after infection. Furthermore, when combined with clarithromycin, MnTE-2-PyP additively reduced the number of cells associated with M. abscessus. A mechanism of bacterial growth inhibition by MnTE-2-PyP was then elucidated. It was found that MnTE-2-PyP promoted the survival of infected THP-1 cells and increased fusion of M. abscessus-containing phagosomes with lysosomes.


Assuntos
Antioxidantes/farmacologia , Macrófagos/microbiologia , Metaloporfirinas/farmacologia , Micobactérias não Tuberculosas/efeitos dos fármacos , Antioxidantes/química , Linhagem Celular , Humanos , Interleucina-8/imunologia , Lisossomos/metabolismo , Macrófagos/citologia , Metaloporfirinas/química , Testes de Sensibilidade Microbiana , Monócitos/citologia , Monócitos/fisiologia , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Micobactérias não Tuberculosas/fisiologia , Fagocitose , Fagossomos/metabolismo , Superóxidos/metabolismo , Fator de Necrose Tumoral alfa/imunologia
20.
J Mol Biol ; 356(1): 57-71, 2006 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-16343530

RESUMO

Cellulose, a polysaccharide consisting of beta-1,4-linked glucose, is the major component of plant cell walls and consequently one of the most abundant biopolymers on earth. Carbohydrate polymers such as cellulose are molecules with vast diversity in structure and function, and a multiplicity of hydrolases operating in concert are required for depolymerisation. The bacterium Rhodothermus marinus, isolated from shallow water marine hot springs, produces a number of carbohydrate-degrading enzymes including a family 12 cellulase Cel12A. The structure of R.marinus Cel12A in the ligand-free form (at 1.54 angstroms) and structures of RmCel12A after crystals were soaked in cellopentaose for two different lengths of time, have been determined. The shorter soaked complex revealed the conformation of unhydrolysed cellotetraose, while cellopentaose had been degraded more completely during the longer soak. Comparison of these structures with those of mesophilic family 12 cellulases in complex with inhibitors and substrate revealed that RmCel12A has a more extensive aromatic network in the active site cleft which ejects products after hydrolysis. The substrate structure confirms that during hydrolysis by family 12 cellulases glucose does not pass through a (2,5)B conformation. Small-angle X-ray scattering analysis of RmCel12A showed that the enzyme forms a loosely associated antiparallel dimer in solution, which may target the enzyme to the antiparallel polymer strands in cellulose.


Assuntos
Celulase/química , Celulase/metabolismo , Oligossacarídeos/metabolismo , Rhodothermus/enzimologia , Temperatura , Sítios de Ligação , Catálise , Celulase/genética , Cromatografia em Gel , Cristalografia por Raios X , Dimerização , Estabilidade Enzimática , Glicerol/farmacologia , Ligação de Hidrogênio , Modelos Moleculares , Oligossacarídeos/química , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Rhodothermus/genética , Homologia Estrutural de Proteína , Especificidade por Substrato
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