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1.
Paediatr Anaesth ; 34(6): 538-543, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38573107

RESUMO

BACKGROUND: The costoclavicular space serves as an alternative approach to the infraclavicular brachial plexus block, and numerous studies in adults have demonstrated promising outcomes for distal upper limb surgery. Blocking the brachial plexus at this level is potentially advantageous because the cords are relatively superficial, located in close proximity to each other and easily identified using ultrasound. AIMS: This study aimed to assess the success rate and feasibility of costoclavicular block in children undergoing unilateral below elbow upper limb surgery. METHODS: Thirty children aged 2-12 years scheduled for unilateral below elbow surgery under general anesthesia were included. Costoclavicular block was performed under ultrasound and nerve stimulator guidance with 0.5% ropivacaine, 0.5 mL/kg. Success was evaluated based on the absence of significant hemodynamic response to skin incision made 20 min after the block. The sono-anatomy of costoclavicular space, ease of needling, complications, and the post-operative pain scores were assessed. RESULTS: The mean age and weight of the children were 6.5 ± 3.8 years and 19.7 ± 9.1 kg, respectively. The success rate of costoclavicular block in our cohort is 100%. Sonographic visualization was graded as excellent (Likert Scale 2) in 90% of cases. The plexus was located at a depth of 1.4 ± 0.3 cm from the skin, the lateral extent of cords from the artery was 0.8 ± 0.4 cm and they were observed inferior and lateral to the artery. The mean needling time was 3.6 ± 1.1 min. None of the children experienced complications such as vascular or pleural puncture, hematoma, Horner's syndrome or diaphragmatic palsy. Postoperative pain scores were low, and no rescue analgesia was required. CONCLUSIONS: In conclusion, the costoclavicular block exhibited a notably high success rate in pediatric population. This study substantiates that the three cords of the brachial plexus are consistently visible and superficial during ultrasound examination using this approach, confirming their separation from vascular structures and the reliable achievement of blockade without observed complications.


Assuntos
Bloqueio Nervoso , Ultrassonografia de Intervenção , Humanos , Criança , Estudos Prospectivos , Pré-Escolar , Masculino , Feminino , Ultrassonografia de Intervenção/métodos , Bloqueio Nervoso/métodos , Bloqueio do Plexo Braquial/métodos , Ropivacaina/administração & dosagem , Anestésicos Locais/administração & dosagem , Dor Pós-Operatória/tratamento farmacológico , Plexo Braquial/diagnóstico por imagem , Clavícula/diagnóstico por imagem
2.
Cardiovasc Intervent Radiol ; 46(8): 1086-1091, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37430015

RESUMO

INTRODUCTION: The safety and efficacy of a microwave ablation (MWA) system for the liver with novel technologies in field control, antenna cooling through the inner part of the choke ring, and dual temperature monitoring were evaluated in this multicenter retrospective study. MATERIAL AND METHODS: Ablation characteristics and efficacy were assessed on follow-up imaging (computed tomography or magnetic resonance imaging). Safety was evaluated according to CTCAE classification. RESULTS: Eighty-seven liver tumors (65 metastases and 22 hepatocellular carcinomas) measuring 17.8 ± 7.9 mm were treated in 68 patients. Ablation zones measured 35.6 ± 11 mm in longest diameter. The coefficients of variation of the longest and shortest ablation diameters were 30.1% and 26.4%, respectively. The mean sphericity index of the ablation zone was 0.78 ± 0.14. Seventy-one ablations (82%) had a sphericity index above 0.66. At 1 month, all tumors demonstrated complete ablation with margins of 0-5 mm, 5-10 mm, and greater than 10 mm achieved in 22%, 46%, and 31% of tumors, respectively. After a median follow-up of 10 months, local tumor control was achieved in 84.7% of treated tumors after a single ablation and in 86% after one patient received a second ablation. One grade 3 complication (stress ulcer) occurred, but was unrelated to the procedure. Ablation zone size and geometry in this clinical study were in accordance with previously reported in vivo preclinical findings. CONCLUSION: Promising results were reported for this MWA device. The high spherical index, reproducibility, and predictability of the resulting treatment zones translated to a high percentage of adequate safety margins, providing good local control rate.


Assuntos
Técnicas de Ablação , Ablação por Cateter , Neoplasias Hepáticas , Humanos , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Reprodutibilidade dos Testes , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Técnicas de Ablação/métodos , Resultado do Tratamento
3.
Int J Clin Pediatr Dent ; 16(1): 112-123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37020773

RESUMO

Background: Preventive therapies rely on effective behavior change. Motivational interviewing (MI), has been the most recent advancement in behavior therapies that have been successful in tobacco cessation. The effectiveness of MI needs to be evaluated in caries prevention. Objectives: To evaluate the effectiveness of MI on the reduction of new carious lesions in children with early childhood caries (ECC). Materials and methods: The two authors independently searched data from Cochrane Library, PubMed, Google Scholar, J gate, and Quintpub. Selection criteria-interventional studies written in the English language with MI as an intervention, a mean follow-up period of atleast 2 years, ECC with decayed, missing, and filled primary teeth/decayed, missing, and filled primary surfaces (dmft/dmfs) as the outcome measures, in the age group of 0-6 years. We excluded cross-sectional studies. Information regarding methods, participants, interventions, outcome measures, and results were extracted. A risk of bias assessment within and across studies was conducted. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria were applied to generate quality evidence. Results: Six studies with a total of 2,663 participants were included in the review, and meta-analysis was conducted on 4; 3 studies had a high risk of bias. A mean reduction of 2.16 (-5.06, 0.75) was observed with MI as an intervention. A sensitivity analysis revealed a mean reduction of 3.64 (-5.77, -1.51) in favor of MI. Conclusion: There is some evidence with moderate certainty that MI is beneficial in the reduction of new carious lesions in children with ECC. How to cite this article: Manek S, Jawdekar AM, Katre AN. The Effect of Motivational Interviewing on Reduction of New Carious Lesions in Children with Early Childhood Caries: A Systematic Review and Meta-analysis. Int J Clin Pediatr Dent 2023;16(1):112-123.

5.
Ann Surg Oncol ; 29(13): 8239-8248, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35974232

RESUMO

BACKGROUND: Textbook oncologic outcome (TOO) is a composite outcome measure realized when all desired short-term quality metrics are met after an oncologic operation. This study examined the incidence and impact of achieving a TOO among patients undergoing resection of gastric adenocarcinoma. METHODS: The 2004-2016 National Cancer Database was queried for patients who underwent curative gastrectomy. Textbook oncologic outcome was defined as having met five metrics: R0 resection, American Joint Committee on Cancer-compliant lymph node evaluation (n ≥ 15), no prolonged hospital stay (< 75th percentile by year), no 30-day readmission, and receipt of guideline-accordant systemic therapy. RESULTS: Of 34,688 patients identified, 8249 (23.8 %) achieved TOO. The patients for whom TOO was achieved were more likely to have traveled farther (p < 0.001) and received care in an academic (p < 0.001) or very high case-volume facility (p < 0.001). The TOO group had a significanty higher median overall survival (OS) than the non-TOO group (80.5 vs 35.3 months; p < 0.001). The Kaplan-Meier curve showed that at 12 months, the survival probability estimate was 92 % for the TOO group versus 77 % for the non-TOO group. At 60 months (long-term survival), survival probability estimates remained higher for the TOO group (57 % vs 38 %). The results of the multivariate Cox regression model found that TOO attainment was significantly associated with a reduced risk of death (hazard ratio, 0.82; p < 0.001). CONCLUSION: The TOO measure is associated with improved OS and reduced risk of death after gastrectomy for gastric adenocarcinoma. Unfortunately, in this study, TOO was obtained in only 23.8 % of cases.


Assuntos
Adenocarcinoma , Neoplasias Gástricas , Humanos , Gastrectomia , Neoplasias Gástricas/patologia , Adenocarcinoma/patologia , Linfonodos/patologia , Readmissão do Paciente , Resultado do Tratamento , Estudos Retrospectivos , Excisão de Linfonodo
6.
Cancers (Basel) ; 13(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063784

RESUMO

The insidious onset and aggressive nature of pancreatic cancer contributes to the poor treatment response and high mortality of this devastating disease. While surgery, chemotherapy and radiation have contributed to improvements in overall survival, roughly 90% of those afflicted by this disease will die within 5 years of diagnosis. The developed ablative locoregional treatment modalities have demonstrated promise in terms of overall survival and quality of life. In this review, we discuss some of the recent studies demonstrating the safety and efficacy of ablative treatments in patients with locally advanced pancreatic cancer.

7.
J Vasc Interv Radiol ; 32(4): 504-509, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33612370

RESUMO

PURPOSE: To evaluate safety and long-term efficacy of radiofrequency (RF) ablation in treatment of chondroblastoma. MATERIALS AND METHODS: This retrospective analysis comprised 27 consecutive patients with histopathologically proven chondroblastoma treated by RF ablation. The tumors were located in the proximal humerus (n = 6), proximal tibia (n = 8), proximal femur (n = 6), distal femur (n = 5), acromion process (n = 1), and lunate (n = 1). In 19 patients (70.3%), the tumor was in the weight-bearing area of the bone. Clinical response was assessed by comparing pain scores and functional assessment by Musculoskeletal Tumor Society (MSTS) score before and after ablation. Patients were followed for a minimum of 1 year to rule out complications and recurrence. RESULTS: Technical success rate was 100%. Mean pain score before the procedure was 7.34 (range, 7-9); all patients experienced a reduction in pain, with 25 (92.6%) patients reporting complete pain relief at 6 weeks. Mean MSTS score before the procedure was 15.4, whereas mean MSTS score at 6 weeks after the procedure was 28.6, suggesting significant functional improvement (P < .0001). Two patients developed osteonecrosis and collapse of the treated bone. There were no recurrences. CONCLUSIONS: Percutaneous RF ablation is a safe and effective option for treating chondroblastoma of the appendicular skeleton.


Assuntos
Neoplasias Ósseas/cirurgia , Condroblastoma/cirurgia , Ablação por Radiofrequência , Adolescente , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/fisiopatologia , Criança , Condroblastoma/diagnóstico por imagem , Condroblastoma/patologia , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Complicações Pós-Operatórias/etiologia , Ablação por Radiofrequência/efeitos adversos , Radiografia Intervencionista , Estudos Retrospectivos , Centros de Atenção Terciária , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
8.
J Oncol Pharm Pract ; 27(4): 1016-1019, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32903144

RESUMO

INTRODUCTION: 5-Fluorouracil is an antineoplastic agent generally used to treat various types of solid tumors. The common adverse drug reaction associated with 5-fluorouracil are myelosuppression, mucositis, diarrhea, and hand-foot syndrome. Neurological side effects such as headache, dizziness, convulsion, encephalopathy, and acute cerebellar syndrome are rare in nature. CASE PRESENTATION: We report a case of 5-fluorouracil induced cerebrovascular accident (CVA) in a patient with no risk factors for CVA before chemotherapy. A 37 years old female patient diagnosed with carcinoma rectum underwent six cycles of chemotherapy with 5- fluorouracil- calcium leucovorin- irinotecan (FOLFIRI regimen). After completing the last cycle, she developed headache, vomiting, and facial deviation along with high blood pressure (260/160 mmHg). MRI brain was done, and it revealed acute non-hemorrhagic lacunar infarct in the left half of pons. 5-fluorouracil induced CVA was suspected and was managed with dual antiplatelet, statin, and antihypertensives. CONCLUSION: The clinicians and clinical pharmacists must be aware about the potential of 5-FU to induce rare side effects such as CVA even in low risk patients in order to avoid permanent harm to the patient.


Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Fluoruracila/efeitos adversos , Acidente Vascular Cerebral/induzido quimicamente , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Colorretais/tratamento farmacológico , Feminino , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico
9.
Urol Case Rep ; 33: 101415, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33102112

RESUMO

Plasmacytoid urothelial carcinoma (PUC) is a rare variant of bladder cancer characterized by distinct histopathology and advanced stage at diagnosis. Multimodal treatment is usually indicated. We present a case of PUC causing bilateral ureteral obstruction with subsequent renal failure followed shortly by malignant small bowel obstruction, demonstrating the need for a high degree of clinical suspicion in diagnosis of this aggressive subtype. Moreover, the local invasiveness of the disease cannot be understated, given that it can rapidly spread with little radiologic evidence of progression until it is at an advanced stage.

10.
Urol Case Rep ; 33: 101261, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32489894

RESUMO

Carcinosarcoma of the kidney and renal pelvis (CSKP) is a rare and highly-aggressive malignancy characterized by rapid progression and widespread metastases. To date, few studies describe the natural history of the disease. We present a patient placed on pembrolizumab therapy for suspected metastatic colon cancer. The patient was found to have a right renal mass with caval extension on surveillance and ultimately underwent radical surgery revealing carcinosarcoma with positive PD-L1 expression with no evidence of recurrence to date. To our knowledge, this is the first case describing PD-L1 expression in CSKP and presents a novel pathway for future treatment algorithms.

11.
Indian J Radiol Imaging ; 27(3): 318-323, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29089682

RESUMO

AIMS: The aim of this study is to evaluate the clinical efficacy of computed tomography (CT)-guided radiofrequency (RF) ablation as a minimally invasive therapy for osteoid osteoma. MATERIALS AND METHODS: This is a retrospective analysis of prospectively maintained data of 43 symptomatic osteoid osteoma patients who were treated by radiofrequency ablation (RFA). Forty out of 43 patients were naive cases and underwent primary treatment for osteoid osteoma with RFA, whereas 3 patients included in the study underwent RFA for local recurrence after having undergone surgical treatment. Diagnosis was based on clinical and characteristic imaging findings, and biopsy was done for cases with atypical presentation. Pre and post procedure Visual Analog Score (VAS) was documented in all cases. Monopolar RFA system was used in all patients, and the electrode was placed within the lesion nidus under CT guidance coaxially through 11G introducer needle. Ablation was performed at 90° C for 5 min. RESULTS: Technical success rate of intranidal placement of electrode was 100%. The primary clinical success in our study was 97.7% (42 of 43), and the secondary clinical success was 100%. Pre and postprocedure VAS score in our study group was 7.8 and 0.4, respectively. Mean follow-up period in our study was 48 months (Range: 4-129 months). One patient had recurrence of pain 4 years after treatment and was treated successfully by a second session. Minor complications were seen in 3 patients with two cases of RF pad burns and one case of skin burn at the treatment site, and these were managed conservatively. No patients developed temporary/permanent neurological deficits, and no procedure-related mortality was seen in our study. CONCLUSION: CT-guided percutaneous RFA is a simple, safe, minimally invasive, and highly effective treatment option for osteoid osteoma with good long-term pain control and potentially low disease recurrence.

12.
World J Radiol ; 9(8): 330-338, 2017 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-28932362

RESUMO

AIM: To elucidate the clinical, magnetic resonance imaging (MRI), pathological features of these lesions and asses the incremental value of diffusion-weighted imaging (DWI) in diagnosing them. METHODS: Fifteen consecutive patients (11 females and 4 males; mean age 40.93 years; age range 13-63 years) with cavernous sinus hemangiomas (CSH) who underwent examination between November 2008 and May 2016 were included for the analysis. MRI, clinical and surgical findings of each patient was retrospectively reviewed. DWI were also analysed and mean-apparent diffusion coefficient (ADC) value was calculated. Eleven patients underwent surgical removal of the lesion and 2 patients had biopsy only. Diagnosis of CSH was confirmed histologically in 13 patients. RESULTS: Eleven patients (73%) presented with headaches and 10 (66%) had cranial nerve involvement. Extra cavernous sinus extension was noted in 14 (94%). Surgery was performed in 13 (87%) and post-operative radiation was given to 4 (28%) patients. Thirteen patients remained asymptomatic on follow up. Three conspicuous imaging features were highly suggestive of the diagnosis: Lack of diffusion restriction (100%), homogeneous hyperintensity on T2 weighted image sequences (93.3%) and intense post-contrast enhancement (100%). The mean ADC was 1.82 × 10-3 ± 0.2186 cm2/s. CONCLUSION: T1-weighted hypointensity with homogeneous hyperintensity on T2-weighted sequences, intense enhancement and absence of hemosiderin within the lesion on GRE sequence favour the diagnosis. Facilitated diffusion on DWI differentiates CSH from other solid cavernous sinus lesions and significantly improves the diagnostic accuracy, a critical factor for planning surgery.

13.
Indian J Radiol Imaging ; 27(2): 200-206, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28744081

RESUMO

AIMS: The study was carried out to evaluate the early outcomes using Radiofrequency Ablation (RFA) for unresectable liver metastases in the management of metastatic colorectal cancer (mCRC) from an area of low endemicity. MATERIAL AND METHODS: 60 Patients with unresectable colorectal liver metastases had undergone 88 sessions of RFA from January 2007 till December 2013. The results were retrospectively analysed to evaluate the outcomes in terms of efficacy and survival rates. RESULTS: The median follow up of patients in our series was 24.8months. 35/52 (67.3%) patients had complete response at 3 months while 8 patients were lost to follow up. Of the 17 patients who had recurrence, 4 (23.5%) were at the ablated site while 13 patients (76.4%) progressed elsewhere. Abdominal pain was commonest post procedural symptom (20%). There was no procedure related mortality or any major complications. Mean disease free interval and Progression free survival was 6.7 and 13.1 months. Estimated median survival in patients with liver limited disease and those with small lesion (<3cm) was 3.79 years and 3.45 years respectively. Median survival in patients with lesion size 3-5 cms was 1.5 years. Annual survival rates would be 94.5%, 55.2% and 26.2% for 1, 3 and 5 years. CONCLUSION: Radiofrequency ablation of unresectable liver metastases is effective in treatment of mCRC. Estimated survival rates and Annual survival rates at our institute from the low endemic region also follow the global trend. Size of the lesion was an important predictor of efficacy of RFA. Presence of extrahepatic disease and lesion size >3 cm was associated with decreased survival.

14.
Insights Imaging ; 6(6): 647-58, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26499189

RESUMO

OBJECTIVES: We aim to illustrate the multimodal imaging spectrum of hepatic involvement in tuberculosis (TB). Whilst disseminated tuberculosis on imaging typically manifests as multiple small nodular lesions scattered in the liver parenchyma, isolated hepatic tuberculosis remains a rare and intriguing entity. METHODS: Indubitably, imaging is the mainstay for detection of tubercular hepatic lesions which display a broad spectrum of imaging manifestations on different modalities. While sonography and computed tomography (CT) findings have been described in some detail, there is a paucity of literature on magnetic resonance imaging (MRI) features. Due to a significant overlap with other commoner and similar appearing hepatic lesions, hepatic tuberculosis is often either misdiagnosed or labelled as indeterminate lesions. This article is a compendium of cases highlighting the spectrum of imaging patterns that can be encountered in patients with isolated primary hepatic tuberculosis as well as disseminated (secondary) disease. Rare patterns of primary disease such as tubercular cholangitis, hypervascular liver masses, and those with vascular complications are also illustrated and discussed. CONCLUSIONS: Imaging plays a valuable role in the detection of tubercular hepatic lesions. Also, imaging can be helpful in their characterisation and for assessing associated complications. TEACHING POINTS: • Hepatic TB has myriad imaging manifestations and is often confounded with neoplastic lesions. • Imaging patterns include miliary TB, macronodular TB, serohepatic TB and tubercular cholangitis. • Concurrent splenic, nodal or pulmonary involvements are helpful pointers towards the diagnosis. • Miliary calcifications along the bile ducts are characteristic of tubercular cholangitis. • Histological/microbiological confirmation is often necessary to confirm the diagnosis.

15.
Funct Integr Genomics ; 15(5): 549-61, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25953511

RESUMO

Glyceollins (Glys), produced by soy plants in response to stress, have anti-estrogenic activity in breast and ovarian cancer cell lines in vitro and in vivo. In addition to known anti-estrogenic effects, Gly exhibits mechanisms of action not involving estrogen receptor (ER) signaling. To date, effects of Gly on gene expression in the brain are unknown. For this study, we implanted 17-ß estradiol (E2) or placebo slow-release pellets into ovariectomized CFW mice followed by 11 days of exposure to Gly or vehicle i.p. injections. We then performed a microarray on total RNA extracted from whole-brain hemispheres and identified differentially expressed genes (DEGs) by a 2 × 2 factorial ANOVA with an false discovery rate (FDR) = 0.20. In total, we identified 33 DEGs with a significant E2 main effect, 5 DEGs with a significant Gly main effect, 74 DEGs with significant Gly and E2 main effects (but no significant interaction term), and 167 DEGs with significant interaction terms. Clustering across all DEGs revealed that transcript abundances were similar between the E2 + Gly and E2-only treatments. However, gene expression after Gly-only treatment was distinct from both of these treatments and was generally characterized by higher transcript abundance. Collectively, our results suggest that whether Gly acts in the brain through ER-dependent or ER-independent mechanisms depends on the target gene.


Assuntos
Encéfalo/metabolismo , Pterocarpanos/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Estradiol/farmacologia , Moduladores de Receptor Estrogênico/farmacologia , Feminino , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ativação Transcricional/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
16.
Bioinform Biol Insights ; 8: 177-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25232279

RESUMO

Retinoblastoma (RB) is a primary childhood eye cancer. HMGA2 shows promise as a molecule for targeted therapy. The involvement of miRNAs in genome-level molecular dys-regulation in HMGA2-silenced RB cells is poorly understood. Through miRNA expression microarray profiling, and an integrated array analysis of the HMGA2-silenced RB cells, the dysregulated miRNAs and the miRNA-target relationships were modelled. Loop network analysis revealed a regulatory association between the transcription factor (SOX5) and the deregulated miRNAs (miR-29a, miR-9*, miR-9-3). Silencing of HMGA2 deregulated the vital oncomirs (miR-7, miR-331, miR-26a, miR-221, miR-17~92 and miR-106b∼25) in RB cells. From this list, the role of the miR-106b∼25 cluster was examined further for its expression in primary RB tumor tissues (n = 20). The regulatory targets of miR-106b∼25 cluster namely p21 (cyclin-dependent kinase inhibitor) and BIM (pro-apoptotic gene) were elevated, and apoptotic cell death was observed, in RB tumor cells treated with the specific antagomirs of the miR-106b∼25 cluster. Thus, suppression of miR-106b∼25 cluster controls RB tumor growth. Taken together, HMGA2 mediated anti-tumor effect present in RB is, in part, mediated through the miR-106b∼25 cluster.

17.
Biomaterials ; 34(30): 7364-71, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23831188

RESUMO

Mesenchymal stem cells (MSCs) although used for bone tissue engineering are limited by the requirement of isolation and culture prior to transplantation. Our recent studies have shown that biomaterial implants can be engineered to facilitate the recruitment of MSCs. In this study, we explore the ability of these implants to direct the recruitment and the differentiation of MSCs in the setting of a bone defect. We initially determined that both stromal derived factor-1alpha (SDF-1α) and erythropoietin (Epo) prompted different degrees of MSC recruitment. Additionally, we found that Epo and bone morphogenetic protein-2 (BMP-2), but not SDF-1α, triggered the osteogenic differentiation of MSCs in vitro. We then investigated the possibility of directing autologous MSC-mediated bone regeneration using a murine calvaria model. Consistent with our in vitro observations, Epo-releasing scaffolds were found to be more potent in bridging the defect than BMP-2 loaded scaffolds, as determined by computed tomography (CT) scanning, fluorescent imaging and histological analyses. These results demonstrate the tremendous potential, directing the recruitment and differentiation of autologous MSCs has in the field of tissue regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Eritropoetina/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quimiocinas/farmacologia , Quimiotaxia/efeitos dos fármacos , Imuno-Histoquímica , Implantes Experimentais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Osteogênese/efeitos dos fármacos , Crânio/diagnóstico por imagem , Crânio/efeitos dos fármacos , Crânio/patologia , Alicerces Teciduais/química , Transplante Autólogo , Microtomografia por Raio-X
18.
Biomaterials ; 33(3): 876-85, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22019117

RESUMO

Inflammatory responses and associated products have been implicated in cancer metastasis. However, the relationship between these two processes is uncertain due to the lack of a suitable model. Taking advantage of localized and controllable inflammatory responses induced by biomaterial implantation and the capability of tissue scaffolds to release a wide variety of chemokines, we report a novel system for studying the molecular mechanisms of inflammation-mediated cancer metastasis. The animal model is comprised of an initial subcutaneous implantation of biomaterial microspheres which prompt localized inflammatory responses, followed by the transplantation of metastatic cancer cells into the peritoneal cavity or blood circulation. Histological results demonstrated that substantial numbers of B16F10 cells were recruited to the site nearby biomaterial implants. There was a strong correlation between the degree of biomaterial-mediated inflammatory responses and number of recruited cancer cells. Inflammation-mediated cancer cell migration was inhibited by small molecule inhibitors of CXCR4 but not by neutralizing antibody against CCL21. Using chemokine-releasing scaffolds, further studies were carried out to explore the possibility of enhancing cancer cell recruitment. Interestingly, erythropoietin (EPO) releasing scaffolds, but not stromal cell-derived factor-1α-releasing scaffolds, were found to accumulate substantially more melanoma cells than controls. Rather unexpectedly, perhaps by indirectly reducing circulating cancer cells, mice implanted with EPO-releasing scaffolds had ~30% longer life span than other groups. These results suggest that chemokine-releasing scaffolds may potentially function as implantable cancer traps and serve as powerful tools for studying cancer distraction and even selective annihilation of circulating metastatic cancer cells.


Assuntos
Quimiocinas/química , Melanoma/metabolismo , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Reação a Corpo Estranho/imunologia , Humanos , Melanoma/imunologia , Melanoma/patologia , Camundongos , Metástase Neoplásica/imunologia , Metástase Neoplásica/fisiopatologia
19.
Indian J Radiol Imaging ; 22(4): 350-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23833428

RESUMO

Medicine is an ever changing field and interventional radiology (IR) procedures are becoming increasingly popular because of high efficacy and its minimally invasive nature of the procedure. Management of disease processes in the extra cranial head and neck (ECHN) has always been a challenge due to the complex anatomy of the region. Cross sectional imaging of the ECHN has grown and evolved tremendously and occupies a pivotal and integral position in the clinical management of variety of head and neck pathologies. Advances in angiographic technologies including flat panel detector systems, biplane, and 3-dimensional rotational angiography have consolidated and expanded the role of IR in the management of various ECHN pathologies. The ECHN is at cross roads between the origins of great vessels and the cerebral vasculature. Thorough knowledge of functional and technical aspects of neuroangiography is essential before embarking on head and neck vascular interventions. The vessels of the head and neck can be involved by infectious and inflammatory conditions, get irradiated during radiotherapy and injured due to trauma or iatrogenic cause. The ECHN is also a common site for various hypervascular neoplasms and vascular malformations, which can be treated with endovascular and percutaneous embolization. This pictorial essay provides a review of variety of ECHN pathologies which were managed by various IR procedures using different approaches.

20.
Biomaterials ; 31(14): 3997-4008, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20185171

RESUMO

Despite significant advances in the understanding of tissue responses to biomaterials, most implants are still plagued by inflammatory responses which can lead to fibrotic encapsulation. This is of dire consequence in tissue engineering, where seeded cells and bioactive components are separated from the native tissue, limiting the regenerative potential of the design. Additionally, these interactions prevent desired tissue integration and angiogenesis, preventing functionality of the design. Recent evidence supports that mesenchymal stem cells (MSC) and hematopoietic stem cells (HSC) can have beneficial effects which alter the inflammatory responses and improve healing. The purpose of this study was to examine whether stem cells could be targeted to the site of biomaterial implantation and whether increasing local stem cell responses could improve the tissue response to PLGA scaffold implants. Through incorporation of SDF-1alpha through factor adsorption and mini-osmotic pump delivery, the host-derived stem cell response can be improved resulting in 3X increase in stem cell populations at the interface for up to 2 weeks. These interactions were found to significantly alter the acute mast cell responses, reducing the number of mast cells and degranulated mast cells near the scaffold implants. This led to subsequent downstream reduction in the inflammatory cell responses, and through altered mast cell activation and stem cell participation, increased angiogenesis and decreased fibrotic responses to the scaffold implants. These results support that enhanced recruitment of autologous stem cells can improve the tissue responses to biomaterial implants through modifying/bypassing inflammatory cell responses and jumpstarting stem cell participation in healing at the implant interface.


Assuntos
Movimento Celular/efeitos dos fármacos , Quimiocina CXCL12/farmacologia , Inflamação/patologia , Ácido Láctico/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Ácido Poliglicólico/farmacologia , Alicerces Teciduais/química , Animais , Citocinas/metabolismo , Reação a Corpo Estranho/patologia , Mobilização de Células-Tronco Hematopoéticas , Implantes Experimentais , Transplante de Células-Tronco Mesenquimais , Camundongos , Camundongos Endogâmicos BALB C , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
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