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1.
J Prosthet Dent ; 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35279301

RESUMO

STATEMENT OF PROBLEM: Various dental implants are available in India, but imported devices are expensive; an affordable locally produced dental implant system would be beneficial. PURPOSE: The purpose of this noninferiority randomized controlled trial was to compare the safety and efficacy of a locally developed dental implant system to those of an established imported dental implant system with similar microsurface characteristics. MATERIAL AND METHODS: A total of 136 participants with 201 partially edentulous sites, aged 18 to 65 years, were enrolled in the trial, with 134 sites receiving test implants and 67 sites control implants (n ratio, 2:1). The implants received a delayed submerged healing protocol and were loaded 3 to 6 months after surgery. Maximum insertion torque (IT) was recorded during the implant surgery, and the implant stability quotient (ISQ) was evaluated on the day of surgery and at the second-stage procedure. The mean crestal bone loss (MCBL) was measured on periapical radiographs at prosthetic placement (baseline) and at 6 months and 12 months after loading. The primary measure of outcome was the implant survival rate, and the secondary measure of evaluation was the intergroup difference in MCBL at baseline, 6 months, and 12 months. RESULTS: A total of 127 test and 61 control implant sites were available for follow-up 1 year after prosthesis placement. At the end of 12 months, the test and control implant groups demonstrated a survival rate of 97% and 100%, respectively. The MCBL difference was significant between the 2 groups at baseline (P<.05). However, at 6 and 12 months, the difference between the test and control groups was not significantly different (P>.05). CONCLUSIONS: The survival rate of the test group fell within the previously assumed 10% noninferiority margin. Therefore, the null hypothesis was accepted for the trial, and the locally developed implants were noninferior to the imported implants at a sample allocation ratio of 2:1.

2.
J Prosthet Dent ; 125(5): 834-838, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32611483

RESUMO

Cranioplasty may be necessary after decompressive craniectomies to aid in the restoration of the esthetic, morphological, functional, and psychosocial stability of those affected. This clinical report describes the management of a comatose road traffic accident victim with a history of autogenous cranial implant failure after decompressive craniectomy. The challenges posed by the nonambulatory state of the patient and his inability to follow commands were overcome by using reverse engineering and rapid prototyping to fabricate a 3D patient-specific polymethylmethacrylate cranial implant. A digital evaluation technique with grids as measuring tools was successfully implemented in the patient's absence. The use of a custom clamp flask aided in the accommodation and subsequent investing, dewaxing, and polymerization of the carved cranial wax pattern. As a result, a custom cranioplast with optimum marginal fit, acceptable contour, adequate thickness, and reduced surgical duration of placement was obtained through a successful combination of conventional and digital techniques.


Assuntos
Implantes Dentários , Procedimentos de Cirurgia Plástica , Coma , Estética Dentária , Humanos , Metilmetacrilato
3.
J Indian Prosthodont Soc ; 20(2): 153-161, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32655219

RESUMO

AIM: Growth factors (GFs) are polypeptides, which are intricately involved in the regulation of bone formation, preservation, and regeneration through gene expression. However, the role of these bioactive agents in osseointegration of dental implants has not been substantially proven. The objective of this systematic review (SR) and meta-analysis was to explore the effect of GFs on early osseointegration of dental implants in animal jaws. An attempt to decipher an adjunctive role of GFs in modulating predictable bone growth in peri-implant areas was done. MATERIALS AND METHODS: An electronic and manual search of different databases was performed. Only randomized controlled trials (RCTs) were included and reviewed. The risk of bias (ROB) of the selected studies was assessed using the SR Centre for Laboratory Animal Experimentation (Cochrane) tool. A meta-analysis was also performed to evaluate the different study characteristics quantitatively. STATISTICAL ANALYSIS USED: The total Weighted mean difference was evaluated using the Rev-Manv5.3 algorithm. Chi-square test and I2 test were done to assess the heterogeneity between the studies. RESULTS: Seven RCTs were included in the study. These were associated with a high ROB. The total weighted mean difference (WMD) of the percentage of bone-implant contact was 3.25% (95% confidence interval [CI] = 1.49%-6.03%; P = 0.001; I2 = 91%) between groups with and without exogenous application of GFs. The total WMD of the percentage of newly formed bone area was 4.48% (95% CI = 2.31%-5.90%; P < 0.00001, I2 = 84%). A high level of heterogeneity (P < 0.001 for Chi-square test; I 2>50 %) among comparable studies was observed. CONCLUSION: The ancillary application of external GFs exhibited evidence of early osseointegration, resulting in more predictable and faster results. However, a careful discernment of conclusions drawn from this SR is a must before conducting any human trials.

4.
RSC Adv ; 8(70): 40198-40209, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-35558247

RESUMO

Hierarchical interconnected nanosheets (HIN) of cobalt manganese nickel sulfide (CoMnNiS) were synthesized on Ni foam by a simple and economical electrodeposition technique for energy storage application. Sulfonated thin nanosheets of Co, Mn and Ni provide stability of chemical activity, surface functionalization and surface reactivity to the electrode. The fabricated electrode shows a specific capacity of 257.4 mA h g-1 (at 2.5 A g-1), measured by galvanostatic charging-discharging (GCD). Both diffusion and capacitive mechanisms in the sulfide layer contribute to the high electrical conductivity. Asymmetric devices CoMnNiS/NiCuO and CoMnNiS/CNT (CNT = carbon nanotubes) were fabricated, providing a maximum operating voltage of 1.7 V and 1 V, specific capacity of 20.8 and 50.8 mA h g-1, and energy density of 8.4 and 6.3 W h kg-1 corresponding to a power density of 985 and 211 W kg-1, respectively, at a current density of 0.5 and 0.63 A g-1. These results demonstrate a novel material for application in energy storage devices as an electrode.

5.
J Craniofac Surg ; 28(8): e735-e737, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28922244

RESUMO

Surgical management of extensive tumors in the mandibular region leads to massive disfigurement of the face. Also the prosthetic outcome of such patients rehabilitated with free soft tissue flaps is very poor. Reconstruction of extensive defects to overcome the disfigurement is a challenging procedure and can be achieved with free fibula flap. Free fibula graft provides sufficient length of bone for the reconstruction of the postsurgical defects. Excellent vascularity of fibula flap allows for easy uptake of the graft and osseointegration of the dental implants. The addition of a skin island allows for absolute tension-free intraoral closure that enhances tongue mobility. Fibula graft allows proper tissue support after mandibular reconstruction. After rehabilitation with free fibula graft we can plan for prosthodontic rehabilitation with implant retained prosthesis leading to improved masticatory function. It also helps to improve speech outcome as a stable prosthesis can be delivered with the help of implants retained in the fibula graft. It is essential to assess the outcome of surgical reconstruction with fibula graft followed by prosthetic rehabilitation with implant retained prosthesis for their recognition as a treatment of preference. This article details the clinical report along with various clinical parameters for implant retained prosthetic rehabilitation of the patient who had undergone mandibular resection and reconstruction with free fibula graft.


Assuntos
Transplante Ósseo/métodos , Fíbula/transplante , Mandíbula , Neoplasias Mandibulares/cirurgia , Osteotomia Mandibular/efeitos adversos , Reconstrução Mandibular/métodos , Complicações Pós-Operatórias/cirurgia , Adulto , Retalhos de Tecido Biológico/transplante , Sobrevivência de Enxerto , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/patologia , Mandíbula/cirurgia , Neoplasias Mandibulares/patologia , Osteotomia Mandibular/métodos , Satisfação do Paciente , Resultado do Tratamento
6.
Contemp Clin Dent ; 8(1): 167-170, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28566873

RESUMO

In maxillary defects, role of a prosthodontist is to rehabilitate the intra- and extra-oral structures and to endow with the normal function of mastication, speech, deglutition, and esthetics. Malignancies are common in the oral region and are treated usually through surgical intervention. Surgical intervention creates anatomical defects creating communication between oral and nasal cavity. Patients pose difficulties while performing normal functions such as swallowing and speaking, due to this communication. To overcome the problems encountered by the patient, obturators are fabricated. The main problem with rehabilitation of large defect is the weight of prosthesis; the prosthesis becomes very bulky and nonretentive due to its weight. Hollow obturators are fabricated to conquer this tribulation by different techniques. This case report describes a simplified method of fabrication of a definitive hollow bulb obturator for rehabilitation of a maxillary defect (Aramany's class I) by insertion of balloon.

7.
Braz. j. oral sci ; 15(4): 280-285, Oct.-Dec. 2016. ilus
Artigo em Inglês | LILACS, BBO | ID: biblio-875804

RESUMO

Radiation-induced oral mucositis (RIOM) is aimed at evaluating the expression of NF-κß, IL-1α, IL-6, IL-8 and TNF-α in patients with RIOM so as to validate their role in the pathobiology of the disease. Blood samples were collected and serum of 45 patients isolated with clinical signs and symptoms of mucositis and 10 healthy controls were also included in the study. The expression level of NF-κß, IL-1α, IL-6, IL-8, TNF-α was investigated using ELISA. Mann Whitney U test was applied to find the significance of the expression of these markers in RIOM patients as compared to normal healthy controls and significant expression (P< 0.05) for NF-κß, IL-6, TNF-α and non-significant expression (P > 0.05) IL-1α and IL-8 was found. No significant change in the expression level of the cytokines was observed for patients undergoing chemotherapy and radiation therapy as well as those receiving only the radiation therapy as a part of their treatment. We have also found less expression in grade 1 of mucositis as compared to grade 4. Pro- inflammatory cytokines indeed play a vital role in the pathogenesis as well as progression of RIOM (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Citocinas , NF-kappa B , Radioterapia , Estomatite
8.
J Prosthet Dent ; 116(2): 300-3, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26996933

RESUMO

Postsurgical injury by teeth to oral mucosa (reconstructed by a flap) can lead to ulceration and subsequent infection at the reconstructed site. A prompt intervention by fabricating a specially designed prosthesis to deflect the reconstruction flap away from the occluding teeth has been described for the treatment of cheek biting in the present clinical report.


Assuntos
Mordeduras Humanas/prevenção & controle , Planejamento de Prótese Dentária , Úlceras Orais/terapia , Idoso , Mordeduras Humanas/complicações , Carcinoma de Células Escamosas/cirurgia , Bochecha , Edema/etiologia , Edema/patologia , Humanos , Masculino , Mucosa Bucal/patologia , Mucosa Bucal/cirurgia , Neoplasias Bucais/cirurgia , Úlceras Orais/etiologia , Retalhos Cirúrgicos , Cicatrização
9.
Br J Oral Maxillofac Surg ; 54(1): 57-61, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26564430

RESUMO

Current published data presents confusing results about the effects of platelet-rich fibrin on bone, and there is a need for studies that throw light on its effect. Our main objective therefore was to evaluate (by fractal analysis) osseous regeneration in extraction sockets with and without platelet-rich fibrin in a study with a substantial sample and a reliable technique to calibrate its effects on bone cells. We also assessed the soft tissue response. Thirty-four patients had their bilaterally impacted third molars (68 surgical sites) extracted in this split-mouth study, following which platelet-rich fibrin was placed in one of the sockets. Patients were followed up clinically and radiographically, and a pain score and fractal analysis were used to evaluate healing of soft tissue and bone, respectively. We conclude that platelet-rich fibrin improves healing of both soft and hard tissues. Although osseous healing did not differ significantly between the groups, healing of soft tissue as judged by the pain score was significantly better in the experimental group.


Assuntos
Plaquetas , Regeneração Óssea , Fibrina , Humanos , Dente Impactado/cirurgia , Cicatrização
10.
J Prosthet Dent ; 115(2): 137-40, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26412002

RESUMO

The problem of small oral aperture is big. Irrespective of the etiology, this problem may be overcome by adjunctive therapies in the form of prosthesis, surgery, or exercise. A patient is described with this problem, which was overcome by revisiting the 3 adjunctive therapies including a commissural stent designed with the patient's edentulous state in mind.


Assuntos
Microstomia/terapia , Boca Edêntula/reabilitação , Próteses e Implantes , Humanos , Masculino , Microstomia/etiologia , Pessoa de Meia-Idade
11.
Contemp Clin Dent ; 6(Suppl 1): S258-61, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26604583

RESUMO

Reduced number of teeth with underdeveloped alveolar ridges poses a greatest prosthetic challenge in rehabilitation of ectodermal dysplasia patients (ED). Furthermore, surgical risks and financial constraints may preclude the implant supported prosthesis, the most desirable treatment option in an adult ED patient. Long edentulous span does not permit fixed dental prosthesis (FDP) as well. Telescopic denture by incorporating the best of both fixed and removable prosthesis can be a viable treatment alternative for ED patients with compromised dentition and limited finances. A 21-year-old young girl presented with chief complaint of esthetics and mastication due to missing upper and lower teeth. A provisional diagnosis of ED was made based on familial history, physical, and oral examination. This clinical report describes management of an adult ED patient by means of telescopic overdenture prosthesis in mandibular arch and FDP in maxillary arch which restored esthetics, function, and social confidence of the patient in a cost effective manner.

12.
J Craniofac Surg ; 26(4): 1313-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26080183

RESUMO

The desired features of a cranioplast include providing an acceptable contour, continuity with the remaining skull (marginal adaptation), improvising the aesthetic outcome, providing a strengthened prosthesis to avoid fracture in case of repeat trauma, and protecting the remaining neurological structures. Combining digital and manual techniques to fabricate a hybrid polymethylmethacrylate cranioplast during the rehabilitation of a pediatric patient with cranial defect has been described. Utilization of digital techniques (rapid prototyping to obtain skull analog) and manual (hand) sculpting of the prosthesis strengthened with glass fiber enabled the authors to fabricate a hybrid cranioplast. Satisfactory outcome was achieved.


Assuntos
Anormalidades Craniofaciais/cirurgia , Metilmetacrilato , Procedimentos de Cirurgia Plástica/métodos , Próteses e Implantes , Crânio/cirurgia , Criança , Desenho Assistido por Computador , Anormalidades Craniofaciais/diagnóstico por imagem , Humanos , Masculino , Desenho de Prótese , Radiografia , Crânio/diagnóstico por imagem
13.
J Indian Prosthodont Soc ; 15(3): 281-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26929526

RESUMO

Surgical resection of soft palate due to cancer affects the effective functioning of the velopharyngeal mechanism (speech and deglutition). With the loss of speech intelligibility, hyper resonance in voice and impaired function of swallowing (due to nasal regurgitation), there is a depreciation in the quality of life of such an individual. In a multidisciplinary setup, the role of a prosthodontist has been described to rehabilitate such patients by fabrication of speech aid prosthesis. The design and method of fabrication of the prosthesis are simple and easy to perform. The use of prosthesis, together with training (of speech) by a speech pathologist resulted in improvement in speech. Furthermore, an improvement in swallowing had been noted, resulting in an improved nutritional intake and general well-being of an individual. The take-home message is that in the treatment of oral cancer, feasible, and rapid rehabilitation should be endeavored in order to make the patient socially more acceptable. The onus lies on the prosthodontist to practise the same in a rapid manner before the moral of the patient becomes low due to the associated stigma of cancer.

14.
Oral Maxillofac Surg ; 19(1): 5-12, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23852077

RESUMO

PURPOSE: The scope of transdermal analgesics have been limited to pain control following local trauma, muscle spasm, minor esthetic surgeries, or sports-related injuries. Its scope of application can be extended in the field of dentistry and minor oral surgical procedures. METHODS: A total of 40 healthy patients between the age of 18 and 50 years with deeply carious, nontender mandibular molar tooth deemed unsalvageable which was indicated for extraction were taken into study of which subjects were divided into cases and controls. RESULTS: The data were analyzed with chi-square test and Mann-Whitney U test; the chi-square test showed significant association with expected outcome in visual analog scale pain scores, the two groups at 6th and 12th hour. A Mann-Whitney U test was performed to identify strength of association between two groups where there were significant association between all parameters except for pain interference with routine activities and dental health status(0.022, 0.001); the differences between two groups in these parameters were significant (<0.05). CONCLUSION: Transdermal route seems to be comparable to oral diclofenac in post-extraction pain relief; further studies are required to confirm the results and safety for its use in various other dental situations.


Assuntos
Diclofenaco/administração & dosagem , Dor Pós-Operatória/tratamento farmacológico , Extração Dentária , Adolescente , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos dos fármacos , Projetos Piloto , Adesivo Transdérmico , Adulto Jovem
15.
BMC Pharmacol Toxicol ; 15: 19, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-24666736

RESUMO

BACKGROUND: GPR40 is a G-protein coupled receptor regulating free fatty acid induced and also glucose induced insulin secretion. We generated neonatally-streptozotocin-treated female rats (n-STZ) and treated them with CNX-011-67, a GPR40 agonist to examine the role of GPR40 in modulation of glucose metabolism, insulin secretion and content. METHODS: Female n-STZ animals were orally administered with CNX-011-67 (15 mg/kg body weight, twice daily) or with vehicle for 8 weeks (n = 8 per group). Glucose tolerance in treated animals and insulin secretion, islet insulin content and gene expression in isolated islets were determined. Islets from type 2 diabetic mellitus (T2DM) patients were treated with different concentrations of glucose in presence or absence of CNX-011-67 and insulin secretion was measured. RESULTS: Treatment of n-STZ rats with GPR40 agonist CNX-011-67 enhanced insulin secretion in response to oral glucose load on day 0 and this response persisted during the treatment period. The treatment also produced a 'memory effect' during which insulin secretion in response to oral glucose load remained enhanced, for a week, even in absence of the agonist. Activation of GPR40 enhanced responsiveness of islets to glucose and increased glucose induced insulin secretion and islet insulin content. An increase in islet mRNA expression of GCK, PDX1, insulin and PC was also observed. Acute treatment of islets from n-STZ rats with GPR40 agonist enhanced cellular ATP content. Activation of GPR40 enhanced mitochondrial calcium level in NIT-1 insulinoma cells. CNX-011-67 increased insulin secretion in islets from T2DM patients which were non-responsive to increased glucose concentration CONCLUSIONS: Our data provide evidence that activation of GPR40 with CNX-011-67 stimulates glucose metabolism, enhances glucose responsiveness, increases insulin secretion and content and that pharmacological activation of GPR40 will prove beneficial for treatment of T2DM.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Feminino , Glucose/metabolismo , Humanos , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Ratos , Ratos Wistar
17.
J Clin Periodontol ; 41(4): 357-65, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24393049

RESUMO

AIM: The present study was designed to find any association of cytokines in women with periodontal disease and development of pre-eclampsia in North Indian population. MATERIALS AND METHODS: A total of 504 consecutively registered primigravida with a single live pregnancy were recruited at 14-18 weeks of gestation from antenatal clinic of Maulana Azad Medical College & associated Lok Nayak Hospital and Maulana Azad Institute of Dental Sciences, New Delhi. One periodontist performed oral health examination of all patients at inclusion into study. Blood samples were collected to measure the level of cytokines IL-4, IL-10, TNF-α and IFN-γ. RESULTS: The profile of blood levels of cytokines from women with periodontal disease was observed. The log serum levels of TNF-α & IL-4 at 16-18 weeks of gestation were significantly higher in women with periodontal disease (4.13 ± 2.06; 0.47 ± 1.56 pg/ml respectively) than in women with healthy gums (2.16 ± 1.51; 0.02 ± 1.84 pg/ml respectively, p < 0.001). Periodontal disease is associated with log serum TNF-α levels at cut-off ≥14.43 pg/ml at sensitivity 71.2% and specificity 62% (OR = 4.04; 95%CI = 2.77-5.87). Woman with periodontal disease who later developed pre-eclampsia had lower levels of TNF-α (3.72 ± 1.33 pg/ml) than those with periodontal disease who did not develop pre-eclampsia (4.20 ± 2.15 pg/ml, p ≥ 0.05). CONCLUSION: Reduced TNF-α level secretion in the early second trimester in women with periodontal disease appears to be associated with the development of pre-eclampsia.


Assuntos
Citocinas/sangue , Doenças Periodontais/imunologia , Pré-Eclâmpsia/etiologia , Adulto , Estudos de Coortes , Feminino , Seguimentos , Gengivite/sangue , Gengivite/imunologia , Humanos , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-4/sangue , Paridade , Perda da Inserção Periodontal/sangue , Perda da Inserção Periodontal/imunologia , Doenças Periodontais/sangue , Bolsa Periodontal/sangue , Bolsa Periodontal/imunologia , Pré-Eclâmpsia/sangue , Gravidez , Resultado da Gravidez , Primeiro Trimestre da Gravidez/sangue , Primeiro Trimestre da Gravidez/imunologia , Segundo Trimestre da Gravidez/sangue , Segundo Trimestre da Gravidez/imunologia , Sensibilidade e Especificidade , Classe Social , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
18.
Spec Care Dentist ; 34(4): 208-11, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24118004

RESUMO

Among the various sequelae associated with the treatment of oral carcinoma (both surgical and radiotherapy), the two conditions that can be of serious concern are reduced mouth opening and mucositis. The limited mouth opening can lead to entrapment of buccal mucosa in between teeth during the chewing cycle, which in turn can lead to further injury of the mucosa. A simple method has been described by the authors to prevent the cheek bite by fabrication of a cheek guard appliance. Favorable results were seen within a few days after insertion of the appliance.


Assuntos
Mordeduras e Picadas , Bochecha/lesões , Protetores Bucais , Adulto , Desenho de Equipamento , Humanos , Masculino
19.
Natl J Maxillofac Surg ; 4(1): 84-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24163559

RESUMO

Median facial dysplasia (MFD) is a distinct and unique disorder of the craniofacial region that is characteristic of deficient mid facial structures with the addition of a unilateral or bilateral cleft lip with or without a cleft palate. A cleft lip which is associated with MFD whether it is unilateral or bilateral does not represent a typical cleft lip and poses some challenges in reconstruction. The management of such cleft lip has been rarely discussed in previous literatures; the main obstacle comes in identifying the anatomical landmarks to establish an esthetic reconstruction of the lip. However, reasonably good result can be achieved when the adjacent and distant anatomical structures are correlated to aid the reconstruction.

20.
BMC Cell Biol ; 14: 31, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23815372

RESUMO

BACKGROUND: In the progression towards diabetes, glucolipotoxicity is one of the main causes of pancreatic beta cell pathology. The aim of this study was to examine the in vitro effects of chronic glucolipotoxic conditions on cellular responses in pancreatic islets, including glucose and fat metabolism, Calcium mobilization, insulin secretion and insulin content. RESULTS: Exposure of islets to chronic glucolipotoxic conditions decreased glucose stimulated insulin secretion in vitro. Reduced protein levels of Glut2/slc2a2, and decreased glucokinase and pyruvate carboxylase mRNA levels indicated a significant lowering in glucose sensing. Concomitantly, both fatty acid uptake and triglyceride accumulation increased significantly while fatty acid oxidation decreased. This general suppression in glucose metabolism correlated well with a decrease in mitochondrial number and activity, reduction in cellular ATP content and dampening of the TCA cycle. Further, we also observed a decrease in IP3 levels and lower Calcium mobilization in response to glucose. Importantly, chronic glucolipotoxic conditions in vitro decreased insulin gene expression, insulin content, insulin granule docking (to the plasma membrane) and insulin secretion. CONCLUSIONS: Our results present an integrated view of the effects of chronic glucolipotoxic conditions on known and novel signaling events, in vitro, that results in reduced glucose responsiveness and insulin secretion.


Assuntos
Cálcio/metabolismo , Glucose/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Mitocôndrias/metabolismo , Palmitatos/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Células Cultivadas , Ácidos Graxos/metabolismo , Glucoquinase/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 2/metabolismo , Técnicas In Vitro , Secreção de Insulina , Células Secretoras de Insulina/patologia , Camundongos , Modelos Animais , Palmitatos/metabolismo , Piruvato Carboxilase/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Triglicerídeos/metabolismo
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