Plasmatic levels of glucose and insulin in siblings of diabetic children (author's transl)

Observation of glucose and plasmatic insulin curve after oral administration of glucose in 16 brothers of juvenile diabetics. The findings were: slight curve alterations that would be compatible with chemical diabetes.     

Alterations of microsatellites in neurofibromas of von Recklinghausen's disease

von Recklinghausen's disease, or type I neurofibromatosis, a common familial tumor syndrome, is characterized by the occurrence of multiple benign neoplasms of nerve sheath cells. The disease is caused by germ-line mutations of the NF1 gene, which encodes a member of the GTPase-activating superfamily of Ras regulatory proteins. We analyzed 5 dinucleotide repeat loci in DNAs from neurofibromas and matched normal skin from 16 NF1 patients. Eight cases (50%) manifested microsatellite alterations. Expansions or compressions of dinucleotide repeats were observed at one locus in four cases and at two loci in one case. Banding patterns compatible with the loss of a microsatellite allele were observed in four cases, including one that also presented microsatellite instability. The surprisingly high frequency of microsatellite alterations suggests that the NF1 gene or another gene(s) contributing to the pathogenesis of neurofibromas might be directly or indirectly implicated in the control of genomic integrity.     

Interactive intraoperative localization during the resection of intraventricular lesions

Mass lesions located in the ventricular system can be surgically challenging. These tumors are often slow growing and reach considerable size before they are diagnosed. These lesions commonly cause multiple obstructions to the circulation of cerebrospinal fluid with subsequent hydrocephalus. They are deeply located in the brain, surrounded by vital neurological and vascular structures, and often have irregular configurations. All these characteristics may pose real problems during surgery in terms of orientation and a optimal resection. For the surgical approach to such intraventricular lesions we are currently using an infrared-based system implemented at Wayne State University that allows intraoperative real-time localization. Three infrared cameras continuously track the position of multiple light-emitting diodes in relation to a predetermined "rigid body". This system can be used with different surgical instruments, and does not interfere with standard neurosurgical techniques. We present our preliminary experience in 18 patients with intraventricular tumors that were operated on between December 1992 and March 1995. Their lesions were located in the lateral ventricles, third ventricle, and pineal region with extension into the posterior aspect of the third ventricle. The use of the interactive infrared-based localizing unit allowed a total resection in 15 cases and a subtotal resection in 3 cases. We report 3 complications, but only one of them was related to the surgical procedure. The postoperative follow-up period ranged from 2 to 24 months. All patients were followed clinically and with postoperative magnetic resonance imaging scans. This interactive infrared system has proven to be a very useful tool, flexible, safe and reliable, increasing surgical efficiency, without a significant increase in the length of resection.     

X-ray image detectors in stomatology]

A low dose (0.2 g) of caffeine had no effect, whereas a high dose (0.4 g) lowered the light sensitivity threshold of the eye retina, as determined by campimetry in young people.