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1.
Pediatr Surg Int ; 38(9): 1209-1215, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35842876

RESUMO

Pelvi-ureteric anastomosis is a critical step to ensure good outcome of pyeloplasty. Continuous suturing technique, especially for laparoscopic surgeries, may offer faster operative time while allowing water-tight anastomosis and remains an alternative to interrupted suturing technique. There has been mixed data on comparison of outcomes of continuous and interrupted suturing techniques. This systematic review and meta-analysis aim to assess the outcomes of pyeloplasty based on continuous and interrupted suturing techniques. Following protocol registration on PROSPERO (CRD42021269706), a systematic review was performed in accordance with Cochrane Collaboration. A literature search was performed in September 2021 across Medline, EMBASE, Scopus, Cochrane Library, and ClinicalTrials.gov. Records comparing pyeloplasty outcomes between continuous and interrupted suture techniques were included. Five studies were identified for inclusion (2 prospective, 3 retrospective). Three studies involved pediatric patients. Three studies exclusively assessed laparoscopic technique. Four outcomes were meta-analyzed: operative time, length of stay, complications, and pyeloplasty failure. Interrupted sutures had longer OR time (mean difference 33.14 min [95% CI 29.35-36.94], p < 0.0001) and length of stay (mean difference 1.08 days [95% CI 0.84-1.32], p < 0.0001). However, there were similar complication (OR 1.73 [95% CI 0.98-3.06], p = 0.06) and failure rates (OR 1.21 [95% CI 0.43-3.43], p = 0.71) between the two suture types. The overall risk of bias in the studies was high. While limited by the number of studies available, continuous sutures for pelvi-ureteric anastomosis appear to confer benefits of faster operative time and decreased length of stay without increasing complication rates or failures.


Assuntos
Laparoscopia , Ureter , Obstrução Ureteral , Criança , Humanos , Pelve Renal/cirurgia , Laparoscopia/métodos , Estudos Prospectivos , Estudos Retrospectivos , Técnicas de Sutura , Suturas , Resultado do Tratamento , Ureter/cirurgia , Obstrução Ureteral/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos
2.
J Urol ; 207(3): 524-533, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34850638

RESUMO

PURPOSE: ß3-adrenergic receptor agonists (ß3 agonists) have been used in treatment of overactive bladder (OAB) and neurogenic detrusor overactivity (NDO) in adults. However, their use in children has only recently been approved by the U.S. Food and Drug Administration for patients with NDO. As in adults, the role of ß3 agonists in children may include conditions such as OAB. This systematic review and meta-analysis aims to understand the intended use, efficacy and safety of ß3 agonists in the pediatric population. MATERIALS AND METHODS: A literature search was performed in February 2021 across MEDLINE®, Embase®, Scopus®, the Cochrane Library and ClinicalTrials.gov. No language restrictions were placed. All records describing the clinical use of ß3 agonists in pediatric patients (<18 years of age) were included, regardless of the methodological design or outcomes assessed. The identified records were screened by 2 independent authors. The reporting was compliant with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Data extraction was performed by 2 independent reviewers, blinded to each other's extractions. The data were pooled using the fixed effects model. RESULTS: Of 367 records identified, 8 studies were included in the review (3 prospective and 5 retrospective). ß3 agonists led to improvements in both urodynamics parameters and self-reported outcomes such as incontinence. Commonly reported side effects were headaches (3%‒5.9%), constipation (3.5%‒5.7%), rhinitis/nasopharyngitis (1.7%‒5.8%) and blurred vision (1.7%‒2.9%). Clinically meaningful changes in safety outcomes (blood pressure, heart rate, electrocardiogram-related changes, liver function) were rare. Before and after ß3 agonist use, pooled effect estimates for maximum cystometric capacity for 171 patients were mean difference of +98.84 ml (95% CI 74.72, 122.96); for complete dryness, assessment of 235 patients showed a Peto odds ratio of 8.68 (95% CI 5.22, 14.45). CONCLUSIONS: ß3 agonists appear to be a promising, effective and safe alternative/adjunctive therapy in management of pediatric NDO or OAB, with improvements in both objective urodynamics parameters and subjective patient-reported outcomes following their use.


Assuntos
Agonistas de Receptores Adrenérgicos beta 3/uso terapêutico , Bexiga Urinaria Neurogênica/tratamento farmacológico , Bexiga Urinária Hiperativa/tratamento farmacológico , Agonistas de Receptores Adrenérgicos beta 3/efeitos adversos , Criança , Humanos , Incontinência Urinária/induzido quimicamente , Urodinâmica/efeitos dos fármacos
3.
Prostate Cancer Prostatic Dis ; 24(1): 96-105, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32424261

RESUMO

BACKGROUND: The relationship between metformin use and prostate cancer risk remains controversial. Genetic variation in metformin metabolism pathways appears to modify metformin glycemic control and the protective association with some cancers. However, no studies to date have examined this pharmacogenetic interaction and prostate cancer chemoprevention. METHODS: Clinical data and germline DNA were collected from our prostate biopsy database between 1996 and 2014. In addition to a genome-wide association study (GWAS), 27 single nucleotide polymorphisms (SNPs) implicated in metformin metabolism were included on a custom SNP array. Associations between metformin use and risk of high-grade (Grade Group ≥ 2) and overall prostate cancer were explored using a case-control design. Interaction between the candidate/GWAS SNPs and the metformin-cancer association was explored using a case-only design. RESULTS: Among 3481 men, 132 (4%) were taking metformin at diagnosis. Metformin users were older, more likely non-Caucasian, and had higher body mass index, Gleason score, and number of positive cores. Overall, 2061 (59%) were diagnosed with prostate cancer, of which 922 (45%) were high-grade. After adjusting for baseline characteristics, metformin use was associated with higher risk of high-grade prostate cancer (OR = 1.76, 95% CI 1.1-2.9, p = 0.02) and overall prostate cancer (OR = 1.77, 95% CI 1.1-2.9, p = 0.03). None of the 27 candidate SNPs in metformin metabolic pathways had significant interaction with the metformin-cancer association. Among the GWAS SNPs, one SNP (rs149137006) had genome-wide significant interaction with metformin for high-grade prostate cancer, and another, rs115071742, for overall prostate cancer. They were intronic and intergenic SNPs, respectively, with largely uncharacterized roles in prostate cancer chemoprevention. CONCLUSIONS: In our cohort, metformin use was associated with increased risk of being diagnosed with prostate cancer. While SNPs involved in metformin metabolism did not have modifying effects on the association with disease risk, one intronic and one intergenic SNP from the GWAS study did, and these require further study.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Metformina/efeitos adversos , Polimorfismo de Nucleotídeo Único , Neoplasias da Próstata/induzido quimicamente , Idoso , Biópsia , Estudos de Casos e Controles , DNA de Neoplasias/genética , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacocinética , Masculino , Metformina/farmacocinética , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Estudos Retrospectivos , Fatores de Risco
5.
Pediatr Surg Int ; 37(1): 161-167, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33136281

RESUMO

INTRODUCTION: This study assesses whether post-operative check-in phone calls (POPC) performed within 48 h of outpatient pediatric urological surgeries by a non-medical professional (NMP) would increase patient/family satisfaction and minimize extraneous resource use by increasing email/telephone communication, while reducing emergency department (ED) visits within 30 days of that procedure. METHODS: Families of patients undergoing ambulatory pediatric urology surgeries were enrolled over 8 weeks. Group 1 did not receive POPC. Group 2 received a POPC within 48 h of their operation by a NMP. Both groups received a phone-call survey 2 weeks after surgery to assess families' perioperative satisfaction. RESULTS: In total, 74 families were enrolled (Group 1 = 44, Group 2 = 31). The response rates to phone surveys for Groups 1 and 2 were 59.1% and 77.4%, respectively. POPC did not improve perioperative satisfaction, nor did it significantly promote the use of nursing email/telephone communication (19.2% vs. 4.2%, p = 0.128) or reduce ED visits (15.4% vs. 0.0%, p = 0.111). However, all families in Group 2 thought POPC was timed appropriately and 79.1% perceived it to be helpful in reducing post-operative anxiety. CONCLUSION: POPC by a NMP within 48 h of surgery may not affect perioperative satisfaction of families of patients undergoing same-day pediatric urology surgery but may have an impact in reducing post-operative anxiety.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/métodos , Continuidade da Assistência ao Paciente/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Relações Profissional-Família , Telefone , Procedimentos Cirúrgicos Urológicos/métodos , Criança , Pré-Escolar , Família/psicologia , Feminino , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Humanos , Lactente , Masculino , Estudos Prospectivos
6.
Cancer Manag Res ; 12: 1163-1173, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104096

RESUMO

BACKGROUND: Blood-based biomarkers (liquid biopsy) are increasingly used in precision oncology. Yet, little is known about cancer patients' perspectives in clinical practice. We explored patients' depth of preferences for liquid vs tissue biopsies and knowledge regarding the role of blood biomarkers on their cancer. METHODS: Three interviewer-administered trade-off scenarios and a 54-item self-administered questionnaire were completed by cancer outpatients across all disease sites at the Princess Margaret Cancer Centre. RESULTS: Of 413 patients, 54% were female; median age was 61 (range 18-101) years. In trade-off scenario preference testing, 90% (n=372) preferred liquid over tissue biopsy at baseline; when wait times for their preferred test were increased from 2 weeks, patients tolerated an additional mean of 1.8 weeks (SD 2.1) for liquid biopsy before switching to tissue biopsy (with wait time 2 weeks). Patients also tolerated a 6.2% decrease (SD 8.8) in the chance that their preferred test would conclusively determine optimal treatment before switching from the baseline of 80%. 216 patients (58%) preferred liquid biopsy even with no chance of adverse events from tissue biopsy. Patients' knowledge of blood-based biomarkers related to their cancer was low (mean 23%); however, the majority viewed development of blood biomarkers as important. CONCLUSION: Patients had limited understanding of cancer-specific blood-based biomarkers, but 90% preferred liquid over tissue biopsies to assess biomarkers. There was little tolerance to wait longer for results, or for decreased test-conclusiveness. Developing accurate, low-risk tests for cancer diagnosis and management for blood biomarkers is therefore desirable to patients.

7.
J Pediatr Surg ; 55(8): 1463-1469, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31679775

RESUMO

BACKGROUND: The clinical and economical value of routine submission of hernia sacs for pathological examination and scheduled clinic follow-ups after inguinal hernia and hydrocele repair has been questioned. Herein, we assessed the institutional variability in these routine practices. METHODS: We retrospectively reviewed patients who underwent unilateral or bilateral inguinal hernia and/or hydrocele repair, open or laparoscopically, at our institution from 2015 to 2018. RESULTS: 1181 patients were included (1074 inguinal hernias and 157 hydroceles). Of 531 specimens obtained from 446 (38%) patients, 515 (97%) were normal. 16 (3%) abnormal pathological findings included 7 with mesothelial hyperplasia, 5 with nonfunctional genital ductal remnants, 3 with ectopic adrenal cortical tissues, and 1 epidydimal structure which was not recognized at the time of surgery. 418 (35%) patients had scheduled clinic follow-ups 65 (IQR 46-94) days postoperatively. 44 (4%) patients with unexpected postoperative Emergency Department visits within 30 days of surgery were identified. Only one patient required inpatient treatment, and the rest did not require intervention or admission. The total direct cost of analyzing specimens during the study period was $30,798 CAD ($10,266/year). The average cost to detect a potentially significant finding was $1924.88/specimen and $2053.20/patient. CONCLUSIONS: Routine pathological examination of hernia sacs and scheduled clinic follow-ups were associated with significant costs and predominantly nonsignificant findings. They should therefore be reserved for patients with a high clinical suspicion of injuries/abnormalities or risk factors for potential complications. LEVEL OF EVIDENCE: This is a level III evidence study.


Assuntos
Hérnia Inguinal , Doenças Peritoneais/cirurgia , Hidrocele Testicular/cirurgia , Pré-Escolar , Feminino , Gônadas/cirurgia , Hérnia Inguinal/diagnóstico , Hérnia Inguinal/patologia , Hospitais Pediátricos , Humanos , Lactente , Masculino , Peritônio/patologia , Peritônio/cirurgia , Estudos Retrospectivos , Centros de Atenção Terciária
8.
Mol Carcinog ; 58(11): 1960-1973, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31355511

RESUMO

Brahma (BRM), of the SWI/SNF complex, has two 6 to 7 bp insertion promoter polymorphisms (BRM-741/BRM-1321) that cause epigenetic BRM suppression, and are associated with risk of multiple cancers. BRM polymorphisms were genotyped in malignant pleural mesothelioma (MPM) cases and asbestos-exposed controls. Multivariable logistic regression (risk) and Cox regression (prognosis) were performed, including stratified analyses by smoking status to investigate the effect of polymorphisms on MPM risk and prognosis. Although there was no significant association overall between BRM-741/BRM-1321 and risk in patients with MPM, a differential effect by smoking status was observed (P-interaction < .001), where homozygous variants were protective (aOR of 0.18-0.28) in ever smokers, while never smokers had increased risk when carrying homozygous variants (aOR of 2.7-4.4). While there was no association between BRM polymorphisms and OS in ever-smokers, the aHR of carrying homozygous-variants of BRM-741, BRM-1321 or both were 4.0 to 8.6 in never-smokers when compared to wild-type carriers. Mechanistically, lower mRNA expression of BRM was associated with poorer general cancer prognosis. Electrophoretic mobility shift assays and chromatin immunoprecipitation experiments (ChIP) revealed high BRM insertion variant homology to MEF2 regulatory binding sites. ChIP experimentation confirmed MEF2 binding only occurs in the presence of insertion variants. DNA-affinity purification assays revealed YWHA scaffold proteins as vital to BRM mRNA expression. Never-smokers who carry BRM homozygous variants have an increased chance of developing MPM, which results in worse prognosis. In contrast, in ever-smokers, there may be a protective effect, with no difference in overall survival. Mechanisms for the interaction between BRM and smoking require further study.


Assuntos
Neoplasias Pulmonares/genética , Mesotelioma/genética , Neoplasias Pleurais/genética , Fumar/efeitos adversos , Fatores de Transcrição/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/patologia , Mesotelioma Maligno , Pessoa de Meia-Idade , Neoplasias Pleurais/patologia , Polimorfismo de Nucleotídeo Único/genética , Prognóstico , Regiões Promotoras Genéticas , Fatores de Risco , Fumar/genética
9.
Can J Surg ; 62(3): 1-6, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30900433

RESUMO

Background: Before 2014, there was a lack of recommendations on managing cryptorchidism, or undescended testis (UDT), from a large pediatric urological or surgical organization. We assessed the variability in management of UDT among pediatric urologists and pediatric surgeons at a single tertiary pediatric referral centre before publication of major guidelines. Methods: We performed a retrospective review of the electronic records of patients who underwent primary unilateral or bilateral orchidopexy at our centre between January 2012 and January 2014. Results: A total of 488 patients (616 testes) were identified, of whom 405 (83.0%) and 83 (17.0%) were managed by pediatric urologists and pediatric surgeons, respectively. There was no difference in baseline characteristics, including age seen in clinic or at surgery, testis location/palpability and availability of preoperative ultrasonograms, of patients seen by the 2 groups. Pediatric surgeons ordered preoperative ultrasonography more often than pediatric urologists (25.3% v. 3.7%, p < 0.001). With palpable UDTs, although both groups used open approaches, pediatric urologists preferred a scrotal approach (56.9%), and pediatric surgeons approached most testes inguinally (98.8%). With nonpalpable UDTs, laparoscopic approaches were preferred by both groups; however, pediatric urologists used a 2-stage Fowler­Stephens approach more often than pediatric surgeons (48.4% v. 15.8%, p < 0.001). Conclusion: There was wide variation in the management of primary UDT between pediatric urologists and pediatric surgeons before the publication of guidelines. The most prominent difference between the 2 groups was in the ordering of preoperative ultrasonography. Future assessment of change in practice patterns may elucidate whether guidelines are an effective tool for standardization of practice.


Contexte: Avant 2014, on ne disposait pas de recommandations émanant d'une grande organisation urologique ou chirurgicale pédiatrique pour la prise en charge de la cryptorchidie (absence d'un ou des deux testicules dans le scrotum). Nous avons évalué les divers types de prise en charge de la cryptorchidie chez les urologues et les chirurgiens pédiatriques dans un seul centre tertiaire de référence pédiatrique avant la publication de lignes directrices majeures. Méthodes: Nous avons procédé à une revue rétrospective des dossiers électroniques de patients ayant subi une orchidopexie unilatérale ou bilatérale primaire dans notre centre entre janvier 2012 et janvier 2014. Résultats: En tout, 488 patients (616 testicules) ont été identifiés, dont 405 (83,0 %) et 83 (17,0 %) ont été traités respectivement par des urologues et des chirurgiens pédiatriques. On n'a noté aucune différence quant aux caractéristiques de départ des patients vus par les 2 groupes, telles que l'âge lors de la consultation à la clinique ou lors de la chirurgie, la localisation/palpabilité des testicules et le recours à l'échographie préopératoire. Les chirurgiens pédiatriques ont demandé une échographie préopératoire plus souvent que les urologues pédiatriques (25,3 % c. 3,7 %, p < 0,001). En présence de cryptorchidie palpable, même si les 2 groupes ont utilisé une approche ouverte, les urologues pédiatriques ont préféré l'approche scrotale (55,4 %) et les chirurgiens pédiatriques l'approche inguinale (98,8 %). En présence de cryptorchidie non palpable, les approches laparoscopiques ont été privilégiées par les 2 groupes; toutefois, les urologues pédiatriques ont utilisé une approche Fowler­Stephens en 2 temps plus souvent que les chirurgiens pédiatriques (48,4 % c. 15,8 %, p < 0,001). Conclusion: On a noté une grande variation dans la prise en charge de la cryptorchidie primaire entre les urologues et les chirurgiens pédiatriques avant la publication des lignes directrices. La principale différence entre les 2 groupes concernait le recours à l'échographie préopératoire. L'évaluation future des changements affectant la pratique permettrait de déterminer si les lignes directrices sont un outil efficace pour sa standardisation.

10.
Can Urol Assoc J ; 13(4): E108-E112, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30273119

RESUMO

INTRODUCTION: Despite the widespread use of circumcision, there is little understanding regarding risk factors associated with its complications. This investigation assesses potential risk factors contributing to complications of circumcision. METHODS: A retrospective review of all males who underwent a neonatal circumcision in our institution's pediatric urology clinic between January 2015 and June 2017 was performed. Continuous variables were dichotomized to determine a clinically relevant cutoff value. Multivariate regression analyses were used to identify risk factors for primary outcomes (early/late complications) and secondary outcomes (emergency room [ER] visitation, return to operating room, post-circumcision communications). RESULTS: A total of 277 patients were identified. The mean age and weight were 28.4 days and 4.3 kg, respectively; 93.1% of cases were elective and 12.3% of patients had comorbidities. Circumcisions were performed using Mogen (61.4%) or Gomco clamps (39.6%) under local anesthesia. Overall, 35 patients experienced complications (12.6%). There were 18 patients (6.5%) with bleeding requiring sutures at time of circumcision. Twenty-six patients (9.4%) experienced long-term complications, with penile adhesions being the majority (84.6%). One (0.4%) of these patients had a Clavien-Dindo 3 complication requiring surgery for a skin bridge that could not be separated. One patient (0.4%) visited the ER due to postoperative bleeding from the circumcised area, which was managed conservatively. Multivariate regression analysis identified weight >5.1 kg as a risk factor for bleeding requiring sutures (odds ratio [OR] 4.145; 95% confidence interval [CI] 1.246-13.799) and long-term complications (OR 3.738; 95% CI 1.356-10.306). No risk factors were identified for other outcomes (return to operating room, ER visitation, post-circumcision email/telephone communications). CONCLUSIONS: This investigation of neonatal circumcision revealed that patients weighing >5.1 kg may be at higher risk of bleeding and long-term complications, such as adhesions.

11.
Proc Natl Acad Sci U S A ; 114(40): 10542-10547, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28923958

RESUMO

Skeletal metastases, the leading cause of death in advanced breast cancer patients, depend on tumor cell interactions with the mineralized bone extracellular matrix. Bone mineral is largely composed of hydroxyapatite (HA) nanocrystals with physicochemical properties that vary significantly by anatomical location, age, and pathology. However, it remains unclear whether bone regions typically targeted by metastatic breast cancer feature distinct HA materials properties. Here we combined high-resolution X-ray scattering analysis with large-area Raman imaging, backscattered electron microscopy, histopathology, and microcomputed tomography to characterize HA in mouse models of advanced breast cancer in relevant skeletal locations. The proximal tibial metaphysis served as a common metastatic site in our studies; we identified that in disease-free bones this skeletal region contained smaller and less-oriented HA nanocrystals relative to ones that constitute the diaphysis. We further observed that osteolytic bone metastasis led to a decrease in HA nanocrystal size and perfection in remnant metaphyseal trabecular bone. Interestingly, in a model of localized breast cancer, metaphyseal HA nanocrystals were also smaller and less perfect than in corresponding bone in disease-free controls. Collectively, these results suggest that skeletal sites prone to tumor cell dissemination contain less-mature HA (i.e., smaller, less-perfect, and less-oriented crystals) and that primary tumors can further increase HA immaturity even before secondary tumor formation, mimicking alterations present during tibial metastasis. Engineered tumor models recapitulating these spatiotemporal dynamics will permit assessing the functional relevance of the detected changes to the progression and treatment of breast cancer bone metastasis.


Assuntos
Densidade Óssea , Neoplasias Ósseas , Neoplasias da Mama , Nanopartículas , Tíbia , Microtomografia por Raio-X , Animais , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/secundário , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Durapatita/metabolismo , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Transplante de Neoplasias , Tíbia/diagnóstico por imagem , Tíbia/metabolismo
12.
Immunity ; 47(1): 66-79.e5, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28723554

RESUMO

Hypoxia augments inflammatory responses and osteoclastogenesis by incompletely understood mechanisms. We identified COMMD1 as a cell-intrinsic negative regulator of osteoclastogenesis that is suppressed by hypoxia. In human macrophages, COMMD1 restrained induction of NF-κB signaling and a transcription factor E2F1-dependent metabolic pathway by the cytokine RANKL. Downregulation of COMMD1 protein expression by hypoxia augmented RANKL-induced expression of inflammatory and E2F1 target genes and downstream osteoclastogenesis. E2F1 targets included glycolysis and metabolic genes including CKB that enabled cells to meet metabolic demands in challenging environments, as well as inflammatory cytokine-driven target genes. Expression quantitative trait locus analysis linked increased COMMD1 expression with decreased bone erosion in rheumatoid arthritis. Myeloid deletion of Commd1 resulted in increased osteoclastogenesis in arthritis and inflammatory osteolysis models. These results identify COMMD1 and an E2F-metabolic pathway as key regulators of osteoclastogenic responses under pathological inflammatory conditions and provide a mechanism by which hypoxia augments inflammation and bone destruction.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Artrite Reumatoide/imunologia , Macrófagos/imunologia , Osteogênese/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Células Cultivadas , Modelos Animais de Doenças , Fator de Transcrição E2F1/metabolismo , Feminino , Humanos , Hipóxia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , NF-kappa B/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais
13.
J Clin Invest ; 127(7): 2555-2568, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28530645

RESUMO

Osteoporosis is a metabolic bone disorder associated with compromised bone strength and an increased risk of fracture. Inhibition of the differentiation of bone-resorbing osteoclasts is an effective strategy for the treatment of osteoporosis. Prior work by our laboratory and others has shown that MYC promotes osteoclastogenesis in vitro, but the underlying mechanisms are not well understood. In addition, the in vivo importance of osteoclast-expressed MYC in physiological and pathological bone loss is not known. Here, we have demonstrated that deletion of Myc in osteoclasts increases bone mass and protects mice from ovariectomy-induced (OVX-induced) osteoporosis. Transcriptomic analysis revealed that MYC drives metabolic reprogramming during osteoclast differentiation and functions as a metabolic switch to an oxidative state. We identified a role for MYC action in the transcriptional induction of estrogen receptor-related receptor α (ERRα), a nuclear receptor that cooperates with the transcription factor nuclear factor of activated T cells, c1 (NFATc1) to drive osteoclastogenesis. Accordingly, pharmacological inhibition of ERRα attenuated OVX-induced bone loss in mice. Our findings highlight a MYC/ERRα pathway that contributes to physiological and pathological bone loss by integrating the MYC/ERRα axis to drive metabolic reprogramming during osteoclast differentiation.


Assuntos
Diferenciação Celular , Osteoclastos/metabolismo , Osteoporose/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptores de Estrogênio/metabolismo , Transdução de Sinais , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Osteoclastos/patologia , Osteoporose/genética , Osteoporose/patologia , Osteoporose/terapia , Proteínas Proto-Oncogênicas c-myc/genética , Receptores de Estrogênio/genética , Transcriptoma , Receptor ERRalfa Relacionado ao Estrogênio
14.
Tissue Eng Part A ; 22(15-16): 1006-15, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27401765

RESUMO

Dynamic mechanical loading is a strong anabolic signal in the skeleton, increasing osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BM-MSCs) and increasing the bone-forming activity of osteoblasts, but its role in bone metastatic cancer is relatively unknown. In this study, we integrated a hydroxyapatite-containing three-dimensional (3D) scaffold platform with controlled mechanical stimulation to investigate the effects of cyclic compression on the interplay between breast cancer cells and BM-MSCs as it pertains to bone metastasis. BM-MSCs cultured within mineral-containing 3D poly(lactide-co-glycolide) (PLG) scaffolds differentiated into mature osteoblasts, and exposure to tumor-derived soluble factors promoted this process. When BM-MSCs undergoing osteogenic differentiation were exposed to conditioned media collected from mechanically loaded breast cancer cells, their gene expression of osteopontin was increased. This was further enhanced when mechanical compression was simultaneously applied to BM-MSCs, leading to more uniformly deposited osteopontin within scaffold pores. These results suggest that mechanical loading of 3D scaffold-based culture models may be utilized to evaluate the role of physiologically relevant physical cues on bone metastatic breast cancer. Furthermore, our data imply that cyclic mechanical stimuli within the bone microenvironment modulate interactions between tumor cells and BM-MSCs that are relevant to bone metastasis.


Assuntos
Neoplasias da Mama/metabolismo , Comunicação Celular , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Transdução de Sinais , Estresse Mecânico , Linhagem Celular Tumoral , Técnicas de Cocultura , Feminino , Humanos , Alicerces Teciduais/química
15.
J Cell Physiol ; 231(2): 449-458, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26189496

RESUMO

Investigations on the therapeutic effects of intravenous immunoglobulin (IVIG) have focused on the suppression of autoantibody and immune complex-mediated inflammatory pathogenesis. Inflammatory diseases such as rheumatoid arthritis are often accompanied by excessive bone erosion but the effect of IVIG on osteoclasts, bone-resorbing cells, has not been studied. Here, we investigate whether IVIG directly regulates osteoclast differentiation and has therapeutic potential for suppressing osteoclast-mediated pathologic bone resorption. IVIG or cross-linking of Fcγ receptors with plate-bound IgG suppressed receptor activator of nuclear factor-κ B ligand (RANKL)-induced osteoclastogenesis and expression of osteoclast-related genes such as integrin ß3 and cathepsin K in a dose-dependent manner. Mechanistically, IVIG or plate-bound IgG suppressed osteoclastogenesis by downregulating RANKL-induced expression of NFATC1, the master regulator of osteoclastogenesis. IVIG suppressed NFATC1 expression by attenuating RANKL-induced NF-κB signaling, explained in part by induction of the inflammatory signaling inhibitor A20. IVIG administration attenuated in vivo osteoclastogenesis and suppressed bone resorption in the tumor necrosis factor (TNF)-induced calvarial osteolysis model. Our findings show that, in addition to suppressing inflammation, IVIG directly inhibits osteoclastogenesis through a mechanism involving suppression of RANK signaling. Direct suppression of osteoclast differentiation may provide beneficial effects on preserving bone mass when IVIG is used to treat rheumatic disorders.


Assuntos
Reabsorção Óssea/terapia , Cisteína Endopeptidases/biossíntese , Imunoglobulinas Intravenosas/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Animais , Reabsorção Óssea/metabolismo , Reabsorção Óssea/patologia , Diferenciação Celular , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/genética , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoclastos/patologia , Ligante RANK/metabolismo , Doenças Reumáticas/metabolismo , Doenças Reumáticas/patologia , Doenças Reumáticas/terapia , Transdução de Sinais , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Fator de Necrose Tumoral alfa/fisiologia
16.
Angew Chem Int Ed Engl ; 54(15): 4440-57, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25801735

RESUMO

High energy-density lithium-ion batteries are in demand for portable electronic devices and electrical vehicles. Since the energy density of the batteries relies heavily on the cathode material used, major research efforts have been made to develop alternative cathode materials with a higher degree of lithium utilization and specific energy density. In particular, layered, Ni-rich, lithium transition-metal oxides can deliver higher capacity at lower cost than the conventional LiCoO2 . However, for these Ni-rich compounds there are still several problems associated with their cycle life, thermal stability, and safety. Herein the performance enhancement of Ni-rich cathode materials through structure tuning or interface engineering is summarized. The underlying mechanisms and remaining challenges will also be discussed.

17.
Nat Commun ; 5: 5418, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25391636

RESUMO

Emerging evidence suggests that RANKL-induced changes in chromatin state are important for osteoclastogenesis, but these epigenetic mechanisms are not well understood and have not been therapeutically targeted. In this study, we find that the small molecule I-BET151 that targets bromo and extra-terminal (BET) proteins that 'read' chromatin states by binding to acetylated histones strongly suppresses osteoclastogenesis. I-BET151 suppresses pathologic bone loss in TNF-induced inflammatory osteolysis, inflammatory arthritis and post-ovariectomy models. Transcriptome analysis identifies a MYC-NFAT axis important for osteoclastogenesis. Mechanistically, I-BET151 inhibits expression of the master osteoclast regulator NFATC1 by suppressing expression and recruitment of its newly identified upstream regulator MYC. MYC is elevated in rheumatoid arthritis macrophages and its induction by RANKL is important for osteoclastogenesis and TNF-induced bone resorption. These findings highlight the importance of an I-BET151-inhibited MYC-NFAT axis in osteoclastogenesis, and suggest targeting epigenetic chromatin regulators holds promise for treatment of inflammatory and oestrogen deficiency-mediated pathologic bone resorption.


Assuntos
Reabsorção Óssea/fisiopatologia , Epigênese Genética/fisiologia , Inflamação/fisiopatologia , Osteoclastos/fisiologia , Osteogênese/fisiologia , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/antagonistas & inibidores , Fatores de Transcrição NFATC/fisiologia , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoporose/fisiopatologia , Ovariectomia , Ligante RANK/fisiologia
18.
J Bone Miner Res ; 28(11): 2357-67, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23649605

RESUMO

Bone metastasis, the leading cause of breast cancer-related deaths, is characterized by bone degradation due to increased osteoclastic activity. In contrast, mechanical stimulation in healthy individuals upregulates osteoblastic activity, leading to new bone formation. However, the effect of mechanical loading on the development and progression of metastatic breast cancer in bone remains unclear. Here, we developed a new in vivo model to investigate the role of skeletal mechanical stimuli on the development and osteolytic capability of secondary breast tumors. Specifically, we applied compressive loading to the tibia following intratibial injection of metastatic breast cancer cells (MDA-MB231) into the proximal compartment of female immunocompromised (SCID) mice. In the absence of loading, tibiae developed histologically-detectable tumors with associated osteolysis and excessive degradation of the proximal bone tissue. In contrast, mechanical loading dramatically reduced osteolysis and tumor formation and increased tibial cancellous mass due to trabecular thickening. These loading effects were similar to the baseline response we observed in non-injected SCID mice. In vitro mechanical loading of MDA-MB231 in a pathologically relevant 3D culture model suggested that the observed effects were not due to loading-induced tumor cell death, but rather mediated via decreased expression of genes interfering with bone homeostasis. Collectively, our results suggest that mechanical loading inhibits the growth and osteolytic capability of secondary breast tumors after their homing to the bone, which may inform future treatment of breast cancer patients with advanced disease.


Assuntos
Neoplasias Ósseas/fisiopatologia , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Osteólise/patologia , Osteólise/fisiopatologia , Tíbia/fisiopatologia , Animais , Neoplasias Ósseas/complicações , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/secundário , Reabsorção Óssea/complicações , Reabsorção Óssea/diagnóstico por imagem , Reabsorção Óssea/patologia , Reabsorção Óssea/fisiopatologia , Neoplasias da Mama/complicações , Neoplasias da Mama/diagnóstico por imagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos SCID , Osteólise/complicações , Osteólise/diagnóstico por imagem , Tíbia/patologia , Alicerces Teciduais/química , Suporte de Carga , Microtomografia por Raio-X
19.
Adv Mater ; 24(9): 1192-6, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22362564

RESUMO

A Li[Li(0.19)Ni(0.16)Co(0.08)Mn(0.57)]O(2) cathode was coated with AlF(3) on the surface. The AlF(3)-coating enhanced the overall electrochemical characteristics of the electrode while overcoming the typical shortcomings of lithium-enriched cathodes. This improvement was attributed to the transformation of the initial electrode layer to a spinel phase, induced by the Li chemical leaching effect of the AlF(3) coating layer.


Assuntos
Compostos de Alumínio/química , Fontes de Energia Elétrica , Fluoretos/química , Lítio/química , Eletrodos , Manganês/química , Níquel/química , Óxidos/química , Propriedades de Superfície
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