A retrospective analysis of lingual nerve sensory changes after mandibular bilateral sagittal split osteotomy

PURPOSE: The purpose of this retrospective study was to determine the patient-reported incidence, duration, and perceived deficit in daily activities associated with lingual nerve (LN) sensory changes after bilateral sagittal split osteotomy (BSSO) of the mandible and to compare them with inferior alveolar nerve (IAN) sensory changes in the same study population. MATERIALS AND METHODS: Questionnaires were mailed to 316 patients who had undergone BSSO procedures between 1980 and 1993. The patients were queried for perceived sensory changes in the distribution of the IAN and LN; duration of these sensory changes; and alteration in daily activities caused by these sensory changes. The same questionnaire was mailed to 47 patients who had undergone isolated genioplasty (GP) to control for the normal variance of non-BSSO surgery on perceived LN sensory changes. RESULTS: Forty-three percent of the BSSO patients and 38% of the GP patients returned the questionnaires. Within the BSSO group, 19.4% reported LN sensory changes, of which 69.3% reported that these changes resolved within 1 year; 88% reported altered daily activities. By comparison, 95.5% reported a perceived IAN sensory change, of which 27.3% reported that these changes resolved within 1 year; 57% reported altered daily activities. Within the GP control group, 11% reported LN sensory changes; none of the reported sensory changes lasted longer than 1 month. CONCLUSIONS: A small percentage of patients report LN sensory changes after BSSO. When compared with IAN reported sensory changes, LN sensory changes resolve more frequently and sooner, but they are associated with greater perceived deficits in daily activity. The interpretation of the reported incidence of LN change must be critically reviewed because control subjects also responded positively.     

Anti-emetic drug effects on pilot performance: granisetron vs. ondansetron

BACKGROUND: The objectives of this study were to evaluate the effects of two anti-emetic drugs, granisetron (1 mg tablets/2 mg oral dose) and ondansetron (8 mg tablets/8 mg oral dose) on flying and mission performance in an F-16 research simulator. METHODS: The experimental approach, involving 9 pilots, was a placebo controlled, double blind, crossover design. Each pilot flew three defensive counter air missions. Data on nine measures of flying performance were collected via the simulator data recorder. In addition, ratings on mission and flying performance were recorded by simulator instructor pilots. Data were also collected on symptoms and side effects, mood, and vigilance. RESULTS: This study, carried out in the context of a simulated tactical air-to-air combat mission, produced no significant differences between the effects of the target drugs and placebo on any of the nine objective flying performance measures, including a composite measure of landing performance. There were no differences in evaluator ratings of routine mission flying or air combat performance. Pilots could not distinguish active drug from placebo and there were no differences on any of the mood scales. CONCLUSIONS: These results confirm our earlier findings that the drugs of interest are well tolerated and produce no cognitive, psychomotor or subjective state changes. In this study, there was no evidence of performance degradation caused by either granisetron or ondansetron when tested in a complex, military task environment.     

The use of X-ray microanalysis to demonstrate the uptake of the molluscicide copper sulphate by slug eggs

Copper has been localized in copper sulphate treated eggs of the slug Agriolimax reticulatus (Mü). This has been accomplished using a freeze-fracture technique, the freeze-dried halves of the fractured eggs being analysed in the scanning electron microscope, using both energy dispersive and wavelength dispersive X-ray microanalysis systems. The distribution of copper obtained using these methods has been compared with that achieved using a standard histochemical technique. Both techniques revealed that the copper is initially retained in the perivitelline membranes. The application of X-ray microanalysis to such studies is discussed.     

Identification of a subdomain within DNA-(cytosine-C5)-methyltransferases responsible for the recognition of the 5' part of their DNA target

In previous work on DNA-(cytosine-C5)-methyltransferases (C5-MTases), domains had been identified which are responsible for the sequence specificity of the different enzymes (target-recognizing domains, TRDs). Here we have analyzed the DNA methylation patterns of two C5-MTases containing reciprocal chimeric TRDs, consisting of the N- and C-terminal parts derived from two different parental TRDs specifying the recognition of 5'-CC(A/T)GG-3' and 5'-GCNGC-3'. Sequences recognized by these engineered MTases were non-symmetrical and degenerate, but contained at their 5' part a consensus sequence which was very similar to the 5' part of the target recognized by the parental TRD which contributed the N-terminal moiety of the chimeric TRD. The results are discussed in connection with the present understanding of the mechanism of DNA target recognition by C5-MTases. They demonstrate the possibility of designing C5-MTases with novel DNA methylation specificities.     

A structure-based model for cytochrome P450cam-putidaredoxin interactions

Putidaredoxin (Pdx) is a Fe2S2 ferredoxin which acts as the physiological reductant of cytochrome P-450cam (CYP101). A model for the solution structure of oxidized Pdx has been determined using NMR methods (Pochapsky et al (1994) Biochemistry 33, 6424-6432). 1H-15N correlations and redox-dependent amide exchange rates have also been described (Lyons et al (1996) Protein Sci 5, 627-639). Data obtained from mutagenesis and kinetic measurements concerning the interactions of Pdx and CYP101 are summarized. A model for the structure of the homologous ferredoxin adrenodoxin (Adx) is also described, and data concerning Adx activity are discussed in relation to this structure. The structures of Pdx and CYP101 were used as starting points for molecular modeling and molecular dynamics simulations. Close approach between the metal centers of the two proteins and interaction between aromatic residues on the surfaces of the proteins are premised. The resulting complex exhibits three intermolecular salt bridges, five intermolecular hydrogen bonds and a 12 A distance between the metal centers. The first direct observations of interaction between Pdx and CYP101 (by two-dimensional NMR of 15N-labeled Pdx in solution with CYP101) are described. The results of the NMR experiments indicate that conformational gating of the electron transfer complex between CYP101 and Pdx may be important.     

Simple chemiluminescent detector for the screening of foodstuffs for the presence of volatile nitrosamines

The construction and subsequent evaluation of an apparatus for the detection of trace amounts of nitrosamines is described. The apparatus consists of a gas chromatograph, a catalytic chamber to generate nitric oxide from eluted nitrosamines, and a chemiluminescent detector to measure the infra-red emission resulting from interaction of this gas with ozone. Examples of the use of the system for determining the nitrosamine concentration in food extracts and other materials are given.