Problems of luxations and fractures of the mandible. A global summarizing overview

A general synthesis of the diagnostic and therapeutic problems related with the mandibular contusions, luxations and fractures is proposed. Emphasis is laid on the evolution of treatment methods, particularly on the various osteosynthesis developed for the last twenty years.     

Quantitative determination of n-propane, iso-butane, and n-butane by headspace GC-MS in intoxications by inhalation of lighter fluid

This report describes a fully elaborated and validated method for quantitation of the hydrocarbons n-propane, iso-butane, and n-butane in blood samples. The newly developed analytical procedure is suitable for both emergency cases and forensic medicine investigations. Its practical applicability is illustrated with a forensic blood sample after acute inhalative intoxication with lighter fluid; case history and toxicological findings are included. Identification and quantitation of the analytes were performed using static headspace extraction combined with gas chromatography-mass spectrometry. In order to reconcile the large gas volumes injected (0.5 mL) with the narrowbore capillary column and thus achieve preconcentration, cold trapping on a Tenax sorbent followed by flash desorption was applied. Adequate retention and separation were achieved isothermally at 35 degrees C on a thick-film capillary column. Sample preparation was kept to a strict minimum and involved simply adding 2.5 microL of a liquid solution of 1,1,2-trichlorotrifluoroethane in t-butyl-methylether as an internal standard to aliquots of blood in a capped vial. Standards were created by volumetric dilution departing from a gravimetrically prepared calibration gas mixture composed of 0.3% of n-propane, 0.7% of iso-butane, and 0.8% of n-butane in nitrogen. In the forensic blood sample, the following concentrations were measured: 90.0 microg/L for n-propane, 246 microg/L for iso-butane, and 846 microg/L for n-butane.     

Radiotherapy alone for primary Merkel cell carcinoma

BACKGROUND: Merkel cell carcinoma is a rare and potentially aggressive cancer of the skin. Cumulative data from small retrospective series have supported treatment by wide excision and adjuvant radiotherapy. However, wide excision may be difficult to perform in patients with tumors of the head and neck or in older populations with comorbidities that may be incompatible with general anesthesia. OBSERVATIONS: Nine patients (group 1) with stage I (without lymph node involvement) Merkel cell carcinoma primary tumors were treated in our center by radiotherapy alone. The rate of recurrence was compared between this group and 17 additional patients (group 2) with stage I Merkel cell carcinoma who received conventional treatment (surgery followed by radiotherapy). RESULTS: The median follow-up was 3.0 years (range, 8 months to 7 years) for group 1 and 4.6 years (range, 5 months to 11 years) for group 2. During this period, we observed 1 relapse and 1 progression of disease in group 2. No statistical difference was found in overall and disease-free survival between the 2 groups of patients. CONCLUSION: This study demonstrates the possibility of treating inoperable Merkel cell carcinoma by radiotherapy alone, with outcomes similar to those of classic treatment.     

Hereditary renal amyloidosis caused by a new variant lysozyme W64R in a French family

BACKGROUND: The number of proteins with mutations resulting in amyloidosis has continued to increase. Five proteins--transthyretin, fibrinogen alpha-A chain, apolipoprotein AI, lysozyme, apolipoprotein AII, cystatin C and gelsolin--can be associated with hereditary amyloidosis involving the kidney. METHODS: A French family with a history of autosomal dominant hereditary amyloidosis with early sicca syndrome and nephropathy leading to renal failure after the fifth to the seventh decade was studied. Several tissue specimens obtained from the proband and his relatives were examined. Immunohistochemistry was performed on paraffin embedded sections using the indirect immunoperoxidase technique. We searched for mutations in the five exons and flanking introns of the lysozyme gene. RESULTS: Amyloid deposits from the bowel, labial salivary gland and kidney were intensively stained by anti-lysozyme antibody. Sequence analysis of lysozyme exon 2 from the affected individuals revealed a nucleotide substitution predicting a substitution of the amino acid at position 64 in the mature protein from tryptophane, an aromatic residue to the cationic residue arginine (W64R). CONCLUSION: We report a novel mutation (W64R) of the lysozyme that is associated with hereditary amyloidosis and prominent nephropathy. Since the treatment of hereditary amyloidosis greatly varies with the nature of the amyloid protein, thorough characterization of the latter is crucial for the management of the disease.     

Assessment of the risk of heat disorders encountered during work in hot conditions

OBJECTIVE: To co-ordinate the work of the main European research teams in the field of thermal factors in order to develop and improve significantly the methods presently available for assessing the risks of heat disorders encountered during work in hot conditions. METHOD: Each item from the required sweat rate model was reviewed on the basis of the most recent literature. A database with 1,113 laboratory and field experiments, covering the whole range of hot working conditions, was assembled and used for the validation. RESULTS: Influence of clothing ensemble on heat exchange: methods and formulas were developed that take into account the dynamic effects associated with forced convection and the pumping effect associated with body movements and exercise. Prediction of the average skin temperature: the model used in the required sweat rate standard ISO 7933 was extended to cover more severe conditions with high radiation and high humidity and different clothing and take into account the rectal temperature for the prediction of the skin temperature. Criteria for estimating acceptable exposure times in hot work environments: criteria were reviewed and updated concerning the maximum increase in core temperature and the acceptable water loss, for acclimatised and nonacclimatised subjects. These limits are intended to protect 95% of the population. Measuring strategy: a strategy was developed to assess the risks in any working situation with varying conditions of climate, metabolic rate or clothing. A detailed methodology was developed in three stages: an "observation" method for the recognition of the conditions that might lead to thermal stress; an "analysis" method for evaluating the problem and optimising the solutions; and an "expert" method for in-depth analysis of the working situation when needed. Validation: the different results were used to prepare a revision of the interpretation procedure proposed in the ISO standard 7933. We validated the modified approaches using the database. This involved the whole range of conditions for which the model was extended, namely conditions with high and low radiation, humidity and air velocity as well as fluctuating conditions. Based on these results, the predicted heat strain model was developed: it is presently proposed as an ISO and CEN standard.     

Co-ordinated strategy of prevention and control of the biomechanical factors associated with the risk of musculoskeletal disorders

OBJECTIVES: To propose a cost-effective set of methods (strategy) to improve biomechanical working conditions and prevent the development of musculoskeletal disorders. METHODS: The strategy was developed according to the philosophy already used for other aspects of working conditions. It was then tested in ten industrial situations with various characteristics, to check its understanding, its usability, and its efficiency. RESULTS: The strategy includes a five-page leaflet ( screening) aimed at motivating the operators to check the problems and bring about immediate solutions if possible. A stage-2 observation checklist is then proposed to guide the discussions during a meeting of the protagonists (workers and management). The assistance of an occupational health practitioner might become indispensable at stage 3 to deepen the analysis of the remaining problems, while experts are requested only in exceptional cases (stage 4, expertise). This strategy was positively judged by the users and proved to be effective in motivating and co-ordinating the protagonists. CONCLUSION: The strategy proved to consider effectively all biomechanical aspects that might contribute to the development of musculoskeletal disorders (MSDs). It proved also to be participatory, placing the operators and their management at the centre of the intervention as the main actors, and organising when to turn to an occupational health practitioner or an expert for assistance.     

Risk of ovarian failure and fertility after intravenous cyclophosphamide. A study in 84 patients

OBJECTIVE: To compare the risk of ovarian failure and the fertility of women treated with intravenous cyclophosphamide (IVCY) according to the underlying inflammatory disease. METHODS: Review of the data of 84 consecutive women: 56 with systemic lupus erythematosus (SLE), 28 with other diseases, mainly Wegener's granulomatosis and systemic vasculitides. RESULTS: The mean age at IVCY initiation was 29 +/- 10 years (range 13-53). The mean dosage was 0.9 +/- 0.14 g per pulse (range 0.5-1), and the mean number of pulses 13 +/- 6.5 (range 3-42). With a mean followup of 5.1 +/- 3.7 years, 23 women developed amenorrhea, with a mean duration of 4 +/- 3.6 months between IVCY initiation and amenorrhea. Amenorrhea was sustained in 19 women (13 with SLE and 6 with other diseases, NS). The mean age at ovarian failure onset was 40 +/- 7.6 years. The risk of ovarian failure correlated with the age at IVCY institution (p < 0.0001), and was independent of underlying inflammatory disease. Eighteen women (13 with SLE and 5 with other diseases) became pregnant during or after CY therapy, with a total of 22 pregnancies. The mean age at IVCY initiation, and the mean number of IVCY (maximum 40 pulses) before pregnancy were similar in women with SLE and those with other diseases. Six pregnancies occurred during IVCY therapy, which ended in induced abortion (n = 3), spontaneous abortion (n = 1), and normal pregnancy after IVCY withdrawal (n = 2) in women who wished to keep their pregnancy despite the risk of teratogenicity. Sixteen pregnancies occurred 2.9 +/- 2.1 years (range 1-9) after IVCY withdrawal. They ended in: 3 induced abortions indicated for severe morphological anomalies (n = 2) and for SLE relapse (n = 1), 3 spontaneous miscarriages, and 10 deliveries of healthy newborns. CONCLUSION: The risk of ovarian failure depends essentially on the age at IVCY initiation. Pregnancy may occur during IVCY therapy, and an efficient contraception is mandatory. After IVCY withdrawal, pregnancy is possible with a favorable outcome in two-thirds of the cases.