Color stability of three composite resins used in the inlay/onlay technique

Abstract – The color stability of three composite resins used in the inlay/onlay technique was determined by means of irradiation with UV-light and by water storage. Generally, water storage resulted in greater changes in color than did UV-light, but no correlation was found between the results of the two chromogenic procedures. The microfilled composite resin was the least color stable material, but none of the resins had alarmingly low color stability.     

DEEP CORNEAL STROMAL OPACITIES WITH CONTACT LENSES

Two patients with deep corneal stromal opacities occurring after prolonged contact lens wear are described. The opacities were associated with folds or striae in Descemet's membrane which they overlay. Development of the opacities was associated with ocular discomfort, photophobia, reduced vision and a history of prolonged daily wearing times. Although the corneal endothelial cell counts were within the normal range, the count was reduced in the affected eye in the patient with the unilateral deep stromal opacity and there was mild polymegathism of the endothelial cells. It is possible that the long-term effects of subtle endothelial cell changes may cause a keratopathy with later scarring and opacification. Poor oxygen trans-missibility, carbon dioxide build-up, or suction effects by the lens may all be aetiological factors. Early recognition and treatment, particularly with a better fitting lens of high oxygen transmissibility is important, as once developed the opacities regress only slowly and may result in permanent visual impairment.     

Unemployment and change of tobacco habits: a study of young people from 16 to 21 years of age

In a cohort study of 1080 pupils who were followed for 5 years from when they left compulsory school (from age 16 to age 21 years), smoking habits were found to correlate with unemployment among both boys and girls. Pupils who zuere smokers in school had a higher risk of becoming unemployed than non-smokers. Irrespective of early smoking, smoking habits developed more unfavourably among unemployed young people than among those with no unemployment during the period studied. The odds ratio of being a smoker at the age of 21 years when unemployed more than 20 weeks during the observation period, compared with those without or with short unemployment, was 2.44 for men and 3.45 for women. When adjusted for the influence of socio-economic background, education, economy and smoking habits at the start of the period, the odds ratio was 1.7 (95% CI 1.01 2.86) for men and 2.0 (1.13–3.53) for women. The adjusted odds ratio for increasing or starting smoking during the period was 1.5 (95% CI 0.89-2.56) for men and 2.0 (1.18–3.35) for women. No significant correlation was found between snuffing and unemployment. Thus, it seems that unemployment is a risk factor for development of tobacco smoking in young people, especially among women.     

Solid-phase synthesis of peptide-4-nitroanilides

A wide variety of Glu/Asp and Gln containing peptide-4-nitroanilides and other chromogenic peptidyl-arylamides could be quickly synthesized by a Fmoc-based solid-phase synthesis strategy employing the side-chain carboxyl groups for transient anchoring to the resin. Suitable synthons for this method, Fmoc-Glu-NH-Np and Fmoc-Asp-NH-Np. were prepared using a diphenylphosphinic chloride-mediated coupling reaction. Peptides of the common structure Suc-Ala-Phe-Pro-Xaa-NH-Np (Xaa = Glu/Asp, Gln) were synthesized and were shown to be substrates for the protease subtilisin Carlsberg (E.C.3,4,21,14a) and for peptidyl-prolyl cis/trans-isomerases (PPIases E.C.5,2,1,8,). The method was extended to amino acids possessing a side chain missing an anchor for binding to the matrix. We synthesized Suc-Ala-Phe-Pro-Gln-Phe-NH-Np anchoring the dipeptide derivative Fmoc-Glu-Phe-NH-Np with the carboxyl group to Rink amide resin using standard SPPS procedures. Additionally this procedure allowed us the preparation of peptidyl-arylamides, utilizing the commercial available Fmoc-Glu-OAll as building block. A mixture of pentapeptide-4-nitroanilides with the general sequence Ala-Ala-Xaa-Pro-Gln-NH-Np was synthesized. Electrospray ionization mass spectrometry (ESI-MS) was used to evaluate the hydrolysis of the peptide mixture by the protease subtilisin Carlsberg. It could be shown that peptides with the hydrophobic amino acids Phe. Tyr, Leu and Val in the varied P3-position were most rapidly cleaved under the chosen conditions. Hydrolysis of the Gln-NH-Np bond in Ala-Ala-Pro-Pro-Gln-NH-Np has not been observed. © Munksgaard 1996.     

Surgical Catheter Ablation of Ventricular Tachycardia Using Left Thoracotomy in a Patient with Hindered Access to the Left Ventricle

We report the case of a patient presenting with incessant monomorphic ventricular tachycardia resistant to antiarrhythmic drugs, and in whom usual percutaneous vascular or pericardial access to the left ventricle was hindered by mechanical aortic and mitral prosthetic valves. Because an epicardial location was suspected by electrocardiogram features and because access to the target area through the coronary sinus was not possible, we decided to perform a surgically based radiofrequency (RF) ablation. Catheter mapping of the epicardial surface through surgical left lateral thoracotomy in the operating room confirmed the epicardial location of the arrhythmogenic substrate and allowed successful RF ablation of the clinically incessant tachycardia. Combined surgical and electrophysiological approach should therefore be performed when RF ablation is needed in case of unadvisable, difficult, or failed nonsurgical percutaneous access.     

KINKY HAIR SYNDROME

Abstract. Møllekær, A. M. (Department of Paediatrics and the Department of Neuropathology, århus University School of Medicine, århus, Denmark). Kinky Hair Syndrome. Acta Paediat Scand, 63289, 1974.–Two brothers with Kinky Hair Syndrome are described. Both of them had hypothermia. In the younger boy low levels of serum copper and ceruloplasrnin were demonstrated. At autopsy the most surprising finding was a demyelinating process in the brain. The fact that the younger boy showed signs of Kinky Hair syndrome at birth makes it difficult to accept an 'intestinal malabsorption of copper as the only underlying defect in the disease.     

Longitudinal Health Risks among Graduates and Non-graduates of Diving School

This longitudinal study examined the health risks (hospitalizations)associated with (a) the hazardous occupation of diving and (b)failing to complete successfully a diver training programme.Comparisons of annual hospitalization rates between graduates(n = 684) and non-graduates (n = 190) of the US Navy DivingSchool revealed no significant differences in rates during the2-year pre-school, or baseline, period. During the 12-year follow-up,there were no significant differences between graduates andnon-graduates in hospitalization rates for diving-related andall other diagnoses, with the exception of the significantlyhigher rate for alcohol/drug dependence among non-graduates.The first 2-year post-school period was the interval of greatestvulnerability for being hospitalized, especially among non-graduateswho had a three-fold increase in hospitalization rates fromthe pre-school period. These results suggested that failingto complete successfully an occupational training programmerepresented a greater health risk to the individual than therisks associated with the hazardous occupation itself. Requests for reprints should be addressed to: Anne Hoiberg, Naval Health Research Center, San Diego, California 92138, USA     

Miscellaneous Symptoms Occurring in Workers Engaged in the Manufacture of PVC

It has been found that 31 vinyl chloride monomer (VCM) workersand 6 ex-workers have complained, in addition to symptoms attributableto recognized pathological changes, of other symptoms of anill-defined and non-specific nature. We consider that thereis evidence that these also may be a result of occupationalexposure.     

OCULAR RIGIDITY AND INTRAOCULAR PRESSURE IN KERATOCONUS

Eighty-five patients with keratoconus and 20 normal controls were studied. Ocular rigidity, calculated using the Friedenwald nomogram, correlated with corneal thinning (p < 0.001) and area of cone (p = 0.05). Schiøtz pressures with increasing weights fell more than normal in Grades 0 to 3 keratoconus, but returned to normal following corneal grafting, as did ocular rigidity. Goldmann applanation pressures were low over the apex of the cone, varying most in eyes with lowest ocular rigidity and with greatest corneal thinning, but also in large sagging cones which had only minimal corneal thinning. Pressures by Mackay-Marg tonometry were normal in keratoconus. The axial length of eyes with keratoconus even after corneal grafting was longer than normal and correlated with myopia. It is concluded that abnormalities of ocular rigidity, Schiøtz and Goldmann pressures in keratoconus are determined by abnormal corneal rigidity. If corneal rigidity is low or corneal thinning is present, Goldmann applanation pressures are falsely low and Mackay-Marg tonometry more closely approximates the true intraocular pressure. The cone develops by stretching with limited loss of tissue and the lower rigidity and reduced apical stress decrease the likelihood of rupture.     

EVALUATION OF AIDS AND EQUIPMENT FOR BATH AND TOILET

Impairment becomes handicap when account is made of the environmentin which the handicapped person exists. In this survey of arthriticsand others in a northern industrial city it was found that manyextrinsic factors were hostile to their maintenance of independencein personal hygiene. Houses were unmodified, toilets and bathroomswere almost universally small, without structural alterations.Aids and adaptations were safe and appreciated but usually arrivedmany weeks after the patient was discharged home. Few patientsreceived instruction in the use of aids prescribed or had theopportunity of seeing a range of equipment. Recommendationsfor an improved service are made. ^*Paper read at a combined meeting of the Heberden Society, theBritish Association for Rheumatology and Rehabilitation, theRoyal Society of Medicine Section of Rheumatology and Rehabilitationand the Irish Society for Rheumatology and Rehabilitation, Dublin,October 15, 1976.