[Assessing knowledge, attitude, and practice on occupational blood exposure in caregiving facilities, in Morocco]. / Evaluation des connaissances, attitudes et pratiques sur les accidents d'exposition au sang en milieu de soins au Maroc.

OBJECTIVE: This study had for aim to evaluate practices and knowledge of infectious hazards, to determine the prevalence of viral infections related to occupational blood exposure among health care workers, and to propose a preventive policy. DESIGN: This descriptive multicentric and transversal epidemiological survey was carried out from 2003 to 2004 in 10 Moroccan cities. Two thousand eight hundred and forty four persons were contacted and 2086 accepted to answer the questionnaire (73.3 %). RESULTS: The mean age was 40.8+/-7.8 years and seniority 15.6+/-7.4 years. Blood was the most incriminated product (96.1%), followed by dirty linen and hospital waste. Instruments most often mentioned as dangerous were hollow needles (80.3%). The most feared infections were viral hepatitis (77.5%) and HIV (89.3%). Only 40.6% of the personnel were adequately vaccinated against hepatitis B. Post-vaccine serology was performed on only 1.8% of the vaccinated staff. During the last 12 months, 58.9% of the personnel underwent at least one occupational blood exposure 5.8% of which was reported. Universal precautions appeared poorly used as only 65.6% wore gloves for invasive acts and 61.5% correctly disinfected their hands. Re-sheathing used needles was frequent (51.2%). CONCLUSIONS: Infectious hazards in healthcare facilities are not sufficiently taken into account: the recent creation of occupational health services in hospital facilities should contribute to improve working conditions, make hepatitis B vaccination available and mandatory, and lead to more information and education on hazards related to occupational blood exposure for healthcare personnel.

[The prevalence of respiratory symptomes and immediate hypersensitivity reactions in a population exposed to flour and cereal dust in five flour mills in Morocco]. / Prevalence des symptômes respiratoires et de sensibilisation de type immédiat dans un echantillon de minotiers au Maroc.

OBJECTIVE: To evaluate the prevalence of respiratory symptoms, ventilatory function disorder and immediate hypersensitivity reactions in a population exposed to flour and cereal dusts in five flour mills in Morocco. METHODS: The study of 373 exposed and 301 non-exposed subjects consisted of an analysis of working conditions and a medical survey. RESULTS AND CONCLUSION: The prevalence of clinical respiratory symptoms was 64.1% among exposed subjects and 41.2% among non-exposed subjects. Cough, expectoration, rhinitis, conjunctivitis, dermatitis, asthma and chronic bronchitis were more frequent among mill-workers. Spirometry was abnormal in 31.6% of those exposed: anomalies were found in both flow and volume. Among exposed subjects with a ventilatory disorder, 77.9% had only small airways syndrome or a light deficit. Smoking was the cause of excess morbidity. Skin prick tests were positive for at least one allergen in 65.4% of exposed compared to 27.2% non-exposed subjects. The prevalence of positive skin tests to occupational allergens alone was higher among those exposed (42.4%) than among the non-exposed (9.9%). The implementation of adequate medical and technical prevention may reduce this risk.

[Respiratory symptoms and ventilatory disorders among a group of cement workers in Morocco]. / Symptômes respiratoires et troubles ventilatoires chez les travailleurs dans une cimenterie au Maroc.

There are 8 cement works in Morocco employing 3 600 people and producing 8 million tons annually. The aim of our study is to determine the prevalence of respiratory symptoms and to propose some preventive measures. The study involved a group of workers of whom 280 were exposed to cement dust (who were further subdivided into three categories according to the intensity of exposure) and 73 who were not. It included a medical history with a standardised questionnaire, a clinical examination and spirometry. 65% of those exposed had clinical symptoms as opposed to 34.2% of the non-exposed. Cough, expectoration rhinitis, chronic bronchitis and asthma were significantly more common with incidences of 56.1%, 52.5%, 49.3%, 29.3% and 14.3% respectively in the exposed against 19.2%, 24.6%, 26%, 9.6% and 6.8% in the non-exposed. Among the exposed the prevalence of chronic bronchitis increased significantly with the degree of exposure, from 11.4% in category 1 to 41.6% in category 3. Age did not seem to influence the development of chronic bronchitis but on the other hand a smoking history of more than 10 years did. Exposure is responsible for the development of respiratory problems because among non smokers the exposed (55.6% are more symptomatic than the non-exposed (13.3%). Tobacco smoking potentiates the effects of occupational airborne contamination because exposed smokers (73.6%) and ex-smokers (67.8%) have more respiratory problems than exposed non-smokers (55.6%). The incidence of abnormalities of respiratory function is significantly higher in the exposed than in the non-exposed (32.5% against 13.7%). Among the exposed workers presenting disorders of ventilatory function 72.5% have no more than a disorder of the small airways or a slight deficit. Among the exposed the prevalence of impaired respiratory function is greater in smokers and ex-smokers (47.9% than in non-smokers (10.4%). Tobacco smoking augments the impairment of respiratory function. Prevention depends therefore on a programme of technical (collective and individual) and medical protection of the workforce.

[The value of occupational health in the national campaign against tuberculosis in Morocco]. / Apport de la medicine du travail dans la lutte nationale contre la tuberculose au Maroc.

Tuberculosis is a major public health problem in Marocco, with an incidence of 100 cases per 100,000 people. Occupational health could make a substantial contribution to the national anti-tuberculosis campaign, as the principal aims of occupational health are to protect and to improve the physical, mental and social well-being of the workforce. Occupational health thus devotes considerable attention to the promotion of health in general, and the fight against tuberculosis in particular. Occupational health physicians can play a major in several areas: prevention, screening, management of patients, compensation and epidemiology. The generalization of medical cover in the work environment in Morocco requires the application of laws already in place, the creation of occupational health departments, the training of occupational health physicians and the raising of their awareness concerning the anti-tuberculosis, and the involvement of doctors in municipal hygiene offices in the framework of a national health program for the entire workforce.

[Respiratory risk in carpenters and cabinet makers]. / Risques respiratoires chez les ouvriers des menuiseries-ébénisteries artisanales.

They are many risks relating to the wood; they are caused by natural components of wood, products of conservation, chemical agents and parasites of wood. We have carried out a retrospective survey which concerned exposed workers and controls in twenty small handicraft workshops in the joiners' souk of Marrakesh, it has enabled us to evaluate the prevalence of the clinical symptoms and disorders of respiratory function in 242 exposed subjects to the wood dust and 121 controls. This enquiry consisted of a questionnaire (European Coal and Steel Community: ECSC and the World Health Organisation: WHO), a clinical examination and a spirometry. Sixty-one point nine % of those exposed had clinical respiratory symptoms versus only 21.5% of controls. Rhinitis, asthma, conjunctivitis, chronic bronchitis and dermATitis were significantly more frequent in those exposed than among the non-exposed, with respectively 55.8%, 14.5%, 24.8%, 21.1% and 12.8% versus 16.5%, 6.6%, 8.3%, 5.8% and 4.9%. Exposure was the cause of respiratory symptoms because among non-smokers, exposed workers were more symptomatic than controls. Smoking exhibited a potentializing effect on airborne occupational contaminants because among exposed workers disorders were 1.8 times more frequent in smokers than non-smokers. A variable degree of respiratory obstruction was found among 30.1% of the exposed individuals versus 12.4% of the unexposed subjects. The effect of exposure was certain because among the non-smokers, 15% of exposed subjects had altered respiratory function versus 4% of unexposed persons. It is imperative to implement an occupational health service and to develop means for collective and individual prevention to maximally reduce the risk.

[Prevalence of respiratory systems and evaluation of sensitization levels in traditional grain market workers in Casablanca]. / Prévalence des symptômes respiratoires et évaluation du degré de sensibilisation chez les ouvriers du souk de céréales de Casablanca.

Our study proposes to evaluate the prevalence of clinical respiratory symptoms, spirometric abnormalities and allergy skin test sensitivities in two groups: on exposed to grain dust in a big traditional grain market in Casablanca and the other unexposed. The inquiry which concerned 277 exposed workers and 230 non exposed consisted of a questionnaire, spirometric examinations and skin prick testings. Exposed and no exposed groups are statically similar as far as physical data (sex, age, weight, heignt) and smoking habits. The atopy was found among 18% of the exposed. The prevalence of clinical respiratory symptomatology among exposed is 64.3% against 24.8% among non exposed. Respiratory symptoms (cough, expectoration), rhinitis, asthma, conjonctivitis, dermatitis, chronic bronchitis were significantly more frequent in those exposed than in the non exposed. Smoking is at the origin of additional morbidity. Atopy seems to be a potentiating factor as all the atopic people exposed are symptomatic. Respiratory function was altered in 37.1% of those exposed versus 12.8% of those no exposed. Among exposed workers with decline of lung function parameters 68.9% have only light anomalies. Tabacco interferes significantly in the alteration of respiratory function parameters. Work exposure to grain associated with smoking resulted in a reduction in respiratory function values. In grain workers, the prevalence of allergy skin test sensitivities of occupational allergens is 30.3% versus 6.9% among those no exposed. The enquiry in the workplace shows complete absence of means of protection for the work force and elevated levels of dust. It is imperative to implement an occupational health service and to develop means for collective and individual prevention to maximally reduce the risk.

Risk factors for Raynaud's phenomenon among workers in poultry slaughterhouses and canning factories.

BACKGROUND: Apart from the use of vibrating tools, little is known about risk factors for Raynaud's phenomenon. However, it has been hypothesized that this disorder may have a multifactorial aetiology, involving potential causal or triggering factors which can be found in the workplace. The objective of the study is to identify individual and occupational risk factors of Raynaud's phenomenon in a population of workers not exposed to vibration, but exposed to cold. METHODS: The survey was carried out in 1987-1988 in 17 poultry slaughterhouses and six canning factories and included 1474 employees. Data were collected at the annual visit to the occupational health physician. Finger sensitivity to cold and Raynaud's phenomenon were identified from a list of symptoms occurring from exposure to cold. The role of potential risk factors was assessed using multiple logistic regression. RESULTS: A high prevalence of symptoms of finger sensitivity to cold was observed. Raynaud's phenomenon was more common in women than in men, was related to family history of the disease but not to smoking or alcohol consumption. After controlling for non-occupational factors, the following working conditions appeared as risk factors for Raynaud's phenomenon: use of plastic gloves, less than four rest breaks, breaks in an unheated place, continual repetition of the same series of operations, exertion of the arm or hand and being able to think of something else while working. CONCLUSION: The study showed that a number of working conditions were associated with an increased risk of Raynaud's phenomenon and finger sensitivity to cold. Changes in working conditions might reduce the risk of this disorder in the food processing industry.

PAF and haematopoiesis: IX. Platelet-activating factor increases DNA synthesis in human bone marrow cells.

Platelet-activating factor (PAF) is present in human bone marrow leading us to investigate its effect on human bone marrow cell proliferation. While PAF (0.1 microM to 1 nM) stimulates the incorporation of [3H]thymidine by freshly isolated adherent human bone marrow cells, PAF has no effect on non adherent cells. A non-metabolizable PAF agonist is more potent than PAF to stimulate thymidine incorporation in adherent cells. The precise role of PAF in human haematopoiesis in vivo remains to be clarified.

[Occupational respiratory risks in workers exposed to enzymes in detergents]. / Risque professionnel respiratoire chez les ouvriers exposés aux enzymes des détergents.

The addition of encapsulated enzymes (proteases and lipases) to detergents in Morocco dates from 1993. We have carried out a retrospective survey which has enabled us to evaluate the prevalence of the clinical symptoms and respiratory function problems in two groups, one exposed and the other non-exposed. This enquiry which concerns 32 exposed workers and 42 non-exposed consisted of a questionnaire (CECA OMS), a chest x-ray and some respiratory function tests. The medical study involves a question in the workplace with an evaluation of dust levels (weight of dust and enzyme activity). Fifty seven per cent of those exposed had clinical respiratory symptomatology against only 7 per cent of those who were not exposed. Rhinitis, asthma, cough, chronic bronchitis, eczema and conjunctivitis were significantly more frequent in those exposed than in the non-exposed. Respiratory function was altered in 65.5 per cent of the exposed against only 38.6 per cent of those who were not exposed. The overall lung function was of an obstructive type. The peak flow (VEMS) were more frequently reduced in those exposed (25 per cent) than in the non-exposed (7.14 per cent). These anomalies were worst at the end of a day's work. Atopy seems to be a potentiating factor. Tobacco interferes significantly in the alteration of respiratory function parameters. The enquiry in the work place revealed evidence of insufficient means of protection for the work force and elevated levels of dust which pass the mean recommended atmospheric values (500 mcg per cubic mm). On the other hand, enzymatic activity of the dust collected remained within normal limits (< 0.5 GU/m3). It is thus imperative to develop means for collective prevention (a more effective encapsulation of the enzymes, work in closed areas, ventilation with more effective dust extraction) and individuals (protective clothing and specific respiratory masks for the enzymes) to maximally reduce the risk.

PAF and hematopoiesis. VIII. Biosynthesis and metabolism of PAF by human bone marrow stromal cells.

Human bone marrow stromal cells were studied for their ability to synthesize and to metabolize platelet-activating factor (PAF), a lipidic compound with potent immunoregulatory properties. When stimulated with 2 microM calcium ionophore for 60 minutes, cultures of stromal cells increased their PAF production (3.52 +/- 0.91 ng/1 x 10(6) cells) compared with controls (0.82 +/- 0.13 ng/1 x 10(6) cells). Addition of exogenous lyso PAF (100 nM) and acetyl-CoA (100 microM) during calcium ionophore stimulation did not change the PAF production. The synthesis of PAF was not influenced by the concentration of albumin in the incubation buffer. The PAF from stromal cells exhibited a hexadecyl chain at the sn-1 position of the molecule, as determined by reverse-phase HPLC. While stromal cells contained low amounts of PAF acetylhydrolase activity and did not secrete it in the culture medium, they metabolized exogenous PAF with 1-alkyl-2-acyl-glycero-phosphocholine and neutral lipids as the major metabolic products. The present results are the first to demonstrate the synthesis and metabolism of PAF by human bone marrow stromal cells. These data suggest that they might be a source of the PAF found in the human bone marrow and/or might be important in the regulation of its levels. The role of PAF on the proliferation and functions of human hematopoietic cells deserves investigation.

Glutathione antioxidant system as a marker of oxidative stress in chronic renal failure.

A profound imbalance between oxidants and antioxidants has been suggested in uremic patients on maintenance hemodialysis. However, the respective influence of uremia and dialysis procedure has not been evaluated. Circulating levels of copper-zinc superoxide dismutase (CuZn SOD), glutathione peroxidase (GSH-Px), and reductase (GSSG-Rd), total GSH and GSSG were determined in a large cohort of 233 uremic patients including 185 undialyzed patients with mild to severe chronic renal failure, and 48 patients treated by peritoneal dialysis or hemodialysis. Compared to controls, erythrocyte GSH-Px and GSSG-Rd activities were significantly increased at the mild stage of chronic uremia (p < .001), whereas erythrocyte CuZn SOD activity was unchanged, total level of GSH and plasma GSH-Px activity were significantly decreased, and GSSG level and GSSG-Rd activity were unchanged. Positive Spearman rank correlations were observed between creatinine clearance and plasma levels of GSH-Px (r = .65, p < .001), selenium (r = .47, p < .001), and GSH (r = .41, p < .001). Alterations in antioxidant systems gradually increased with the degree of renal failure, further rose in patients on peritoneal dialysis and culminated in hemodialysis patients in whom an almost complete abolishment of GSH-Px activity was observed. In conclusion, such disturbances in antioxidant systems that occur from the early stage of chronic uremia and are exacerbated by dialysis provide additional evidence for a resulting oxidative stress that could contribute to the development of accelerated atherosclerosis and other long-term complications in uremic patients.

PAF and haematopoiesis: III. Presence and metabolism of platelet-activating factor in human bone marrow.

Platelet-activating factor (PAF) is a phospholipid compound with major immunoregulatory activities. The present study shows that human bone marrow contains 576 +/- 39 pg PAF/ml (n = 35). Bone marrow-derived PAF exhibits the same biophysical and biological properties that synthetic PAF. PAF concentrations in bone marrow are correlated with the granulocyte (r = 0.4, P = 0.02) but not with the lymphocyte (r = 0.24, P = 0.17) and the monocyte (r = 0.12, P = 0.48) counts. In bone marrow PAF is inactivated by a plasma PAF acetylhydrolase activity (48.0 +/- 2.3 nmol/min per ml, n = 34). Experiments with [3H]PAF indicate that human bone marrow cells actively metabolize this potent molecule by the deacetylation-transacylation pathway. Results of this investigation indicate the permanent presence of significant amounts of PAF in bone marrow suggesting its putative involvement in the processes of bone marrow cell proliferation and maturation.

Balance between IL-1 beta, TNF-alpha, and their specific inhibitors in chronic renal failure and maintenance dialysis. Relationships with activation markers of T cells, B cells, and monocytes.

Patients with end-stage renal disease present an immunodeficiency that paradoxically coexists with activation of most immunocompetent cells, and the roles of chronic uremia and maintenance dialysis are poorly understood. We determined circulating levels of IL-1 beta and IL-1Ra, TNF-alpha and its soluble receptors (TNF-sR55 and TNF-sR75), and activation markers of T cells (soluble CD25), B cells (soluble CD23), and monocytes (neopterin) in a large cohort of undialyzed patients at various stages of chronic renal failure and in dialyzed patients on maintenance hemodialysis or chronic peritoneal dialysis. The progression of uremia was associated with a gradual increase in soluble CD25, CD23, and especially neopterin levels. Although IL-1 beta could not be detected, IL-1Ra levels were significantly increased from the earliest stage of renal failure. Plasma levels of TNF-alpha, TNF-sR55, and TNF-sR75 progressed with the severity of renal failure and correlated with soluble CD25, CD23, and neopterin levels, whereas IL-1Ra levels correlated exclusively with TNF-sR55 levels. Compared with undialyzed patients, levels of IL-1 beta were higher in patients on maintenance hemodialysis, whereas those of IL-1Ra were lower and decreased further at the end of dialysis sessions. In contrast, both TNF-sR55 and TNF-sR75 levels were significantly higher than in undialyzed patients and increased further at the end of dialysis sessions in the absence of an increase of TNF-alpha. Such an imbalance between cytokines and their inhibitors may play a pivotal role in the multifaceted process of immune dysfunction.

Soluble CD23 as an effector of immune dysregulation in chronic uremia and dialysis.

Patients with chronic renal failure often present an immunodeficiency state paradoxically exacerbated by hemodialysis and associated with signs of T cell activation. The presence of circulating monokines suggests that monocytes are also activated. Whether or not this includes B cells is controversial, despite frequently abnormal antibody responses. We thus investigated whether the soluble low-affinity receptor for IgE (Fc epsilon RII/CD23), recently identified as a marker of B cell and monocyte activation and possibly involved in T cell activation, was modulated by chronic renal failure and hemodialysis. Relative to values in healthy individuals (N = 31), plasma concentrations of soluble CD23 were significantly elevated in non-dialyzed chronically uremic patients (N = 44), more elevated in patients on peritoneal dialysis (N = 24), and most elevated in those on regular hemodialysis (N = 132), stabilizing after about six months. Soluble CD23 levels were unmodified by the first dialysis session but rose markedly during regular dialysis with cellulose or polysulfone membranes, but not with polyacrilonitrile AN-69 membranes. Soluble CD23 levels correlated with levels of IgG, and those of tumor necrosis factor alpha and interleukin-6, suggesting that increased sCD23 levels reflect activation of B cells and monocytes, respectively. These findings reinforce the view of soluble CD23 as a multi-functional receptor/cytokine, and provide evidence that it might contribute to the immune dysregulation associated with chronic renal failure and exacerbated by hemodialysis.

Rheumatic syndromes and beta 2-microglobulin amyloidosis in patients receiving long-term peritoneal dialysis.

We studied 56 patients who had been receiving peritoneal dialysis for greater than 3 years, to investigate the prevalence of rheumatic diseases suggestive of beta 2-microglobulin (beta 2m) amyloid deposition. Eight patients were found to have carpal tunnel syndrome, 16 had chronic shoulder pain, 8 had subchondral bone cysts, and 13 had destructive arthropathies. Amyloid reacting with anti-beta 2m was demonstrated in the hip synovium of 1 patient. Serum beta 2m levels were elevated in all patients. These data suggest that peritoneal dialysis, like hemodialysis, may lead to the development of an arthropathy associated with beta 2m accumulation and beta 2m amyloid deposition.

Stimulatory effects of protein synthesis inhibitors on the spreading rate of 3T3 cells.

Three protein synthesis inhibitors, puromycin, cycloheximide and anisomycin were found to increase the rate of spreading of Swiss-3T3 cells after 1 h incubation in the presence of low concentrations of serum. Data from experiments with anisomycin suggest that this effect is roughly proportional to the extent of inhibition of protein synthesis.

[Encapsulating peritonitis during continuous ambulatory peritoneal dialysis. A physiopathologic hypothesis]. / Péritonite encapsulante au cours de dialyse péritonéale continue ambulatoire. Hypothèse physiopathologique.

A case of sclerosing encapsulating peritonitis was observed in a patient who had been treated by continuous ambulatory peritoneal dialysis for 4 years. During that period the patient had always used a lactate buffered dialysate (Dianeal solution, supplied by Travenol) and no disinfectant. Nine episodes of peritonitis occurred during the first two years of dialysis. At the end of the first year the patient had decreased ultrafiltration associated with high glucose absorption. A peritoneal biopsy performed at that time showed mesothelial alterations and desquamation. Sclerosing encapsulating peritonitis was suspected at the end of the fourth year, on the basis of changes in the glucose equilibration curve which showed that poor ultrafiltration was now associated with very slow glucose absorption. The diagnosis was confirmed at laparotomy. The authors suggest that the first stage of encapsulating peritonitis might be prolonged and severe alteration of the mesothelial layer. Dialysis should be discontinued immediately in the presence of a loss of filtration with hypermeability (type I) in order to permit normal recovery. If this is not done, loss of filtration with severe hypopermeability (type II) may develop due to multiple adhesions or to the encapsulating process.

Growth-promoting effects of iron- and cobalt- protoporphyrins on cultured embryonic cells.

The effects of hemin (Fe-protoporphyrin) and Co-protoporphyrin on cellular growth have been investigated principally in cultured fibroblasts, but also in myoblasts and hepatocytes from chick embryos. In the presence of horse serum in the culture medium, which by itself did not stimulate cell growth appreciably, Co-protoporphyrin stimulated cell attachment while hemin stimulated cell proliferation of fibroblasts. When Co-protoporphyrin and hemin were added together, the most potent stimulation of cell growth, consisting of increases in cell attachment and rapid cell proliferation, was observed. These findings indicate that the two metalloporphyrins have differential and complementary effects on cellular growth in culture, with synthetic Co-protoporphyrin principally affecting cellular attachment and Fe-protoporphyrin stimulating cellular proliferation.