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51.
Glioblastoma muhiforme (GBM) is a highly invasive brain tumour that is unvaryingly fatal in humans clesplte even aggres- sive therapeutic approaches such as surgical resection followed by chemotherapy and radiotherapy. Unconventional treatment options such as gene therapy provide an intriguing option for curbing glioma related deaths. To date, gene therapy has yielded encouraging results in preclinical animal models as well as promising safety profiles in phase I clinical trials, but has failed to demonstrate significant therapeutic efficacy in phase III clinical trials. The most widely studied antiglioma gene therapy strategies are suicide gene therapy, genetic immuno- therapy and oncolytic virotherapy, and we have attributed the challenging transition of these modalities into the clinic to four major road- blocks : ( 1 ) anatomical features of the central nervous system, (2) the host immune system, (3) heterogeneity and invasiveness of GBM and (4) limitations in current GBM animal models. In this review, we discuss possible ways to jump these hurdles and develop new gene therapies that may be used alone or in synergy with other modalities to provide a powerful treatment option for patients with GBM. 相似文献
52.
S. Girish Rao Preethi Bhat K. S. Nagesh Gundu H. R. Rao Bharthi Mirle Lubna Kharbhari B. Gangaprasad 《Journal of maxillofacial and oral surgery》2013,12(1):11-16
Aim
To evaluate the effects of autologous platelet rich fibrin gel (PRF gel) on bone regeneration following extraction.Materials and Methods
The study design was approved by the Institutional Ethical Committee. Study sample consisting of a total of 22 patients requiring bilateral transalveolar third molar extractions were included after written informed consent. One side was randomly chosen as case and the other side was the control. Autologous PRF gel was prepared from Fresh blood obtained from the patient. The PRF gel was placed in the extraction site and primary closure was obtained. The patient was called for a follow up on the first post op day, 1st week, one month, three month and six months post op. Regeneration of bone was measured using serial radiographs (RVG) at immediate post op, one, three and six months. This was then compared with the bone regeneration seen in the control group, with the radiographs taken at same intervals, to estimate the difference in bone regeneration if any. RVGs were assessed for amount of radiologic bone filling by the method described by Matteo Chiapasco et al.Results and Conclusion
Higher mean pixels was recorded in cases compared to controls at all the time intervals viz., immediate post op, 1 month post op, 3 months post op and 6 months post op. However, the difference in the mean pixels recorded between the two groups was not statistically significant (P > 0.05). For complete analysis, further follow up of the present patients and a larger sample size is required to obtain a conclusive result of the Bone Regeneration in extraction sockets with PRF gel. 相似文献53.
K. Deepak Pai Muralee Mohan Kehava K. Bhat T. Anju Gopinathan 《Journal of Pierre Fauchard Academy (Pierre Fauchard Academy. India Section)》2013,27(4):109-112
Removal of extensive central skull base and paranasal sinus tumors is a significant challenge that is often hampered by limited access and exposure. The safety and efficacy of the Le Fort I osteotomy approach to the skull base have been well established. The purpose of this article is to describe the use of Le fort-1I osteotomy as an access procedure to reach tumors in the nasopharyngeal region in a young patient. The large mass which he presented within the nasopharyngeal region, later diagnosed to be juvenile nasopharyngeal angiofibroma, posed a challenge for surgical access. 相似文献
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56.
A heterostructure of WS2/WO3·H2O has been prepared by partial oxidation of WS2 nanosheets by exposing bulk WS2 micron powder to ultrasonic waves in a bath sonicator. The as-prepared nanomaterial was used as a sensing film in an interdigitated electrode-based gas detecting device. The device was found to be specific towards ammonia gas among a group oxidizing and reducing gases. In particular, a response of as high as 11.36–254.66% was recorded for ammonia concentrations of 50 ppb to 2 ppm with excellent repeatability and reproducibility at room temperature. The response time and recovery time of the device was found to be a few tens of seconds suggesting its practicability. A plausible mechanism based on different active sites present in the receptor film is proposed and a logical reason behind its specificity towards ammonia gas is also inferred based on the Lewis acidic centers on the nano-surfaces. Overall, this proposed nanomaterial has very high potential for practical use as a room temperature ammonia sensor.A tungsten sulfide/tungstite heterostructure is prepared via a modified liquid exfoliation technique. A chemiresistive sensor based on this nanomaterial demonstrates excellent sensitivity and selectivity towards ammonia gas even at room temperature. 相似文献
57.
Pradeep Bhaskar Jiju John Suresh K. Sivamurthy Reyaz A. Lone Pawel A. Tysarowski Mohammed K. Riyas Syed A. Syed Akhlaque N. Bhat Ahmed Sallehuddin 《Journal of clinical anesthesia》2013,25(6):488-490
The anesthetic implications of Joubert syndrome in an infant who required cardiac surgery using cardiopulmonary bypass (CPB) is presented. Children with Joubert syndrome present with central apnea due to malformations in the midbrain and cerebellum. These patients have a marked sensitivity to opioids. The use of dexmedetomidine along with remifentanil was effective in this case. 相似文献
58.
Robert DOrtenzio Stefano Tolhurst Melissa Harvey Ravi Ghag Manraj KS Heran 《Journal of Radiology Case Reports》2021,15(3):1
Mass lesions presenting at the craniocervical junction often present a unique challenge due to the complex anatomic arrangement limiting access for tissue diagnosis. The transoral approach has predominantly been used for percutaneous vertebroplasty of high cervical vertebrae with limited literature describing image guided biopsy for bony lesions in this region in the pediatric patient. We describe a technique of computed tomography guided transoral biopsy of a poorly differentiated chordoma located at the C1–C2 level in a 5-year-old child, and review this diagnosis. 相似文献
59.
Aditi Sinha Geetika Singh Abdus Sami Bhat Sarita Mohapatra Ashima Gulati Pankaj Hari J. C. Samantaray Amit Kumar Dinda Sanjay Kumar Agarwal Arvind Bagga 《Clinical and experimental nephrology》2013,17(1):66-72
Background
Infection with Plasmodium vivax, a common human parasite, is occasionally recognized to cause severe organ dysfunction similar to P. falciparum infection. Acute kidney injury (AKI) in malaria is attributed to acute tubular necrosis; thrombotic microangiopathy is not described.Methods
This observational study includes patients referred to a tertiary care center in North India during June to September 2011 with severe AKI, anemia, and thrombocytopenia following vivax malaria. Renal biopsies were processed by light, immunofluorescence, and electron microscopy.Results
Nine patients (including 5 children) had persistent AKI with thrombocytopenia and variable anemia following the diagnosis of malaria. Based on peripheral smear, eight patients were diagnosed with vivax malaria and had received antimalarial therapy prior to referral; a laboratory diagnosis of P. vivax infection was made for one patient at this center. Renal histology in all cases showed features of thrombotic microangiopathy, including fibrin thrombi, subendothelial widening, and mesangiolysis, along with variable tubulointerstitial nephritis and acute tubular or cortical necrosis. Ultrastructural examination confirmed endothelial injury and subendothelial widening. All patients required hemodialysis, and six were dialysis dependent at four weeks. Delayed presentation to the hospital (P = 0.019), hemolysis on peripheral smear (P = 0.083), and prolonged oligoanuria (P = 0.036) were associated with dialysis dependence.Conclusion
The association of anemia, thrombocytopenia, and renal histological evidence of thrombotic microangiopathy with vivax malaria is novel, and suggests the presence of severe endothelial injury. Further studies are necessary to confirm the association and examine the factors associated with its occurrence. 相似文献60.