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31.
H K Mehta 《The British journal of ophthalmology》1989,73(7):488-493
Fifteen patients with suspected malignant lesions of the lower eyelids or inner canthal region, needing large excisions, were managed as day cases with spontaneous repair and simultaneous subtotal primary surgical reconstruction under local anaesthesia. For lesions confined to the lower eyelid, only those patients requiring full-thickness margin-inclusive (FTMI) excisions of more than half the horizontal extent of the eyelid are included in this study-the largest excision being 21 x 6 mm. For malignant lesions of the inner canthus, only those patients needing moderate to large excision of inner canthal skin and orbicularis with simultaneous FTMI excision of the medial one-third (8 x 5 mm) of the upper as well as the lower eyelid are included. The 16th patient had traumatic loss of inner canthal tissue. The final cosmetic and functional results in all 16 patients were satisfactory and comparable with the results of competent and in-toto primary surgical reconstructions. For large excisions at the inner canthus spontaneous with partial primary surgical repair allows the use of a less extensive and less elaborate surgical procedure that is within the capabilities of most ophthalmic surgeons. 相似文献
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33.
The potential of topoisomerase I inhibitors in the treatment of CNS malignancies: report of a synergistic effect between topotecan and radiation 总被引:1,自引:0,他引:1
Summary Despite innovations in imaging, surgery, and radiation therapy, local failure remains the principle clinical problem in most CNS malignancies. To date, chemotherapy has not made a major impact in the treatment of most adult CNS tumors. The inroads made by chemotherapy in pediatric CNS malignancies suggest that novel drugs, or drug combinations, may improve therapy. Topoisomerase I (Topo I) inhibitors are a relatively new group of chemotherapy drugs with a novel mechanism of action. Drugs in this group currently undergoing clinical trials are the Camptothecin analogues Topotecan, CPT-11, and 9-aminocamptothecin. There is substantial preclinical and some clinical evidence to suggest that these drugs could be useful in the treatment of CNS malignancies. Preclinical studies with the water soluble Topo I inhibitor, Topotecan, demonstrate antineoplastic activity in a variety of CNS malignancies. In addition, Topotecan has good CNS penetration in primates, and recent preliminary phase I and II clinical trials of Topotecan in pediatric and adult CNS malignancies have been promising. In this paper, we describe the unique mechanism of action, antineoplastic activity, and radiosensitizing properties of Topo I inhibitors. We present the first report demonstrating potentiation of radiation lethality by Topotecan in a human glioma (1354) cell line. The dose enhancement ratio was 3.2 at 10% survival. Thus, there is evidence to suggest that Topo I inhibitors may be beneficial in the treatment of CNS neoplasms on the basis of their antineoplastic activity alone, as well as their radiosensitizing effects. Two clinical trials which utilize concurrent Topotecan and radiation in the treatment of pediatric and adult CNS malignancies are discussed. 相似文献
34.
Head injury mortality in two centers with different emergency medical services and intensive care 总被引:7,自引:0,他引:7
A R Colohan W M Alves C R Gross J C Torner V S Mehta P N Tandon J A Jane 《Journal of neurosurgery》1989,71(2):202-207
The authors report data collected prospectively on 551 cases of head injury in New Delhi, India, and 822 cases in Charlottesville, Virginia. The mortality rate, adjusted for initial severity of injury, was 11.0% in New Delhi versus 7.2% in Charlottesville (p less than 0.02). There was a striking similarity in mortality rates at both centers when comparing patients with the least severe head injuries and those with the most severe injuries according to the motor score of the Glasgow Coma Scale (GCS M). However, in the group with an abnormal but purposeful motor response (GCS M = 5), the mortality rate was 12.5% in New Delhi versus 4.8% in Charlottesville (p less than 0.01). The relative absence of prehospital emergency care and the delay in admission after head injury in New Delhi are cited as two possible causes for the differences in mortality rates in this subgroup of patients with "moderate" head injuries. 相似文献
35.
36.
S Vijayakumar K Shepard F Thomas J Weick T Rice A Mehta 《Journal of the National Medical Association》1987,79(5):496-504
The role of radiotherapy in small cell carcinoma of the lung is unsettled; however, the radiosensitivity of this neoplasm is unquestioned. The ability of radiotherapy to cure or improve patients with this disease is still undergoing study. A review of this challenging subject is presented. 相似文献
37.
Adenosine kinase (AK) from CHO cells has been purified to homogeneity and specific antibodies to it have been raised in rabbits. Using this antibody, the presence of a specific cross-reacting protein (CRP) in cell extracts of different classes of mutants resistant to purine nucleoside analogs which are affected in AK has been investigated by the immunoblotting technique. Results of our studies show that 31 of the 32 independently selected class A AK– mutants (obtained at high frequency in presence of adenosine analogs toyocamycin, tubercidin, 6-methylmercaptopurine riboside, or pyrazofurin and containing no measurable activity of AK in cell extracts) contained similar amounts of a specific CRP as seen in the parental AK+ cells. The CRP in the parental and different mutant cell lines has the same relative molecular mass as purified AK. Similar results were obtained with two mutants each of the class B and C type (selected in presence of C-nucleosides formycin A and formycin B), which are also affected in AK but show novel properties. The presence of equivalent amounts of the CRP in the vast majority of the class A mutants strongly indicates that the high frequency of those mutants in CHO cells is not a result of an epigenetic or deletion type of event, but that such mutants may contain missense types of mutations at a presumed mutational hot spot within the structural gene for adenosine kinase. 相似文献
38.
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40.
Alan Ma Sunita Gurnasinghani Edwin P. Kirk Conor McClenaghan Gautam K. Singh Dorothy K. Grange Chetan Pandit Yung Zhu Tony Roscioli George Elakis Michael Buckley Bhavesh Mehta Philip Roberts Jonathan Mervis Andrew Biggin Colin G. Nichols 《American journal of medical genetics. Part A》2019,179(8):1585-1590
Cantú syndrome (CS), characterized by hypertrichosis, distinctive facial features, and complex cardiovascular abnormalities, is caused by pathogenic variants in ABCC9 and KCNJ8 genes. These genes encode gain‐of‐function mutations in the regulatory (SUR2) and pore‐forming (Kir6.1) subunits of KATP channels, respectively, suggesting that channel‐blocking sulfonylureas could be a viable therapy. Here we report a neonate with CS, carrying a heterozygous ABCC9 variant (c.3347G>A, p.Arg1116His), born prematurely at 32 weeks gestation. Initial echocardiogram revealed a large patent ductus arteriosus (PDA), and high pulmonary pressures with enlarged right ventricle. He initially received surfactant and continuous positive airway pressure ventilation and was invasively ventilated for 4 weeks, until PDA ligation. After surgery, he still had ongoing bilevel positive airway pressure (BiPAP) requirement, but was subsequently weaned to nocturnal BiPAP. He was treated for pulmonary hypertension with Sildenafil, but failed to make further clinical improvement. A therapeutic glibenclamide trial was commenced in week 11 (initial dose of 0.05 mg–1 kg–1 day–1 in two divided doses). After 1 week of treatment, he began to tolerate time off BiPAP when awake, and edema improved. Glibenclamide was well tolerated, and the dose was slowly increased to 0.15 mg?1 kg?1day?1 over the next 12 weeks. Mild transient hypoglycemia was observed, but there was no cardiovascular dysfunction. Confirmation of therapeutic benefit will require studies of more CS patients but, based on this limited experience, consideration should be given to glibenclamide as CS therapy, although problems associated with prematurity, and complications of hypoglycemia, might limit outcome in critically ill neonates with CS. 相似文献