Maleic acid is a biomarker for maleylacetoacetate isomerase deficiency; implications for newborn screening of tyrosinemia type 1.

Dried blood spot succinylacetone (SA) is often used as a biomarker for newborn screening (NBS) for tyrosinemia type 1 (TT1). However, false-positive SA results are often observed. Elevated SA may also be due to maleylacetoacetate isomerase deficiency (MAAI-D), which appears to be clinically insignificant. This study investigated whether urine organic acid (uOA) and quantitative urine maleic acid (Q-uMA) analyses can distinguish between TT1 and MAAI-D. We reevaluated/measured uOA (GC-MS) and/or Q-uMA (LC-MS/MS) in available urine samples of nine referred newborns (2 TT1, 7 false-positive), eight genetically confirmed MAAI-D children, and 66 controls. Maleic acid was elevated in uOA of 5/7 false-positive newborns and in the three available samples of confirmed MAAI-D children, but not in TT1 patients. Q-uMA ranged from not detectable to 1.16 mmol/mol creatinine in controls (n = 66) and from 0.95 to 192.06 mmol/mol creatinine in false-positive newborns and MAAI-D children (n = 10). MAAI-D was genetically confirmed in 4/7 false-positive newborns, all with elevated Q-uMA, and rejected in the two newborns with normal Q-uMA. No sample was available for genetic analysis of the last false-positive infant with elevated Q-uMA. Our study shows that MAAI-D is a recognizable cause of false-positive TT1 NBS results. Elevated urine maleic acid excretion seems highly effective in discriminating MAAI-D from TT1.

Prenatal exposure to betamethasone causes intergenerational impairment of epididymal development in the rat.

BACKGROUND: Studies on epididymal toxicology are scarce. Betamethasone (BM) is a glucocorticoid used in clinical practice for antenatal therapy. We previously reported changes to testicular morphology, altered sperm quality, and fertility in adult rats following intrauterine administration of BM. OBJECTIVES: Given that high levels of corticosteroids during gestation lead to fetal androgen depletion, and the essential role of testosterone during epididymal development, here we investigated epididymal morphology and physiology in the F1 and F2 male offspring of female rats treated with BM during gestation. MATERIALS AND METHODS: Pregnant rats were randomly divided into two experimental groups: control (saline vehicle, n = 11) and BM-treated group (0.1 mg/kg betamethasone 21-phosphate disodium, n = 13). Rats received an intramuscular injection of vehicle or BM on gestational days 12, 13, 18, and 19. This encompasses the beginning of the critical window of male rat reproductive tract development. A subset of three males from each litter (n = 5 litters/group) was used: One rat per litter was euthanized at puberty, one was euthanized at adulthood, while the others were mated with a non-treated female to obtain the F2 generation. The same protocol described for the F1 was applied for F2, except for the mating protocol. RESULTS: In both F1 and F2 generations, prenatal BM exposure resulted in delayed differentiation of the cauda epididymal epithelium, characterized by increased cribriform appearance on PND 45, and displayed weaker or non-detectable Cx43 immunostaining. Furthermore, in the F1 generation only, immunostaining of TP63, a transcription factor expressed in basal cells, appeared more intense with a greater number of TP63-positive cells observed in the cauda epididymis. In adults, the epithelial area was reduced in the F1 BM rats. The contractile activity of isolated epididymal ducts was comparable between groups. DISCUSSION AND CONCLUSION: Prenatal BM exposure leads to intergenerational impairment in the development and structure of the rat epididymis.

Tissue regeneration and the epididymal stem cell.

BACKGROUND: In most pseudostratified epithelia, basal cells represent a multipotent adult stem cell population. These cells generally remain in a quiescent state, until they are stimulated to respond to tissue damage by initiating epithelial regeneration. In the epididymis, cell proliferation occurs at a relatively slow rate under normal physiological conditions. Epididymal basal cells have been shown to share common properties with multipotent adult stem cells. The development of organoids from stem cells represents a novel approach for understanding cellular differentiation and characterization of stem cells. OBJECTIVE: To review the literature on tissue regeneration in the epididymis and demonstrate the presence of an epididymal stem cell population. METHODS: PubMed database was searched for studies reporting on cell proliferation, regeneration, and stem cells in the epididymis. Three-dimensional cell culture of epididymal cells was used to determine whether these can develop into organoids in a similar fashion to stem cells from other tissues. RESULTS: The epididymal epithelium can rapidly regenerate following orchidectomy or efferent duct ligation, in order to maintain epithelial integrity. Studies have isolated a highly purified fraction of rat epididymal basal cells and reported that these cells displayed properties similar to those of multipotent adult stem cells. In two-dimensional cell culture conditions, these cells differentiated into cells which expressed connexin 26, a marker of columnar cells, and cytokeratin 8. Furthermore, three-dimensional cell culture of epididymal cells resulted in the formation of organoids, a phenomenon associated with the proliferation and differentiation of stem cells in vitro. CONCLUSIONS: The rapid proliferation and tissue regeneration of the epididymal epithelium to preserve its integrity following tissue damage as well as the ability of cells to differentiate into organoids in vitro support the notion of a resident progenitor/stem cell population in the adult epididymis.

Evaluating genetic susceptibility to Staphylococcus aureus bacteremia in African Americans using admixture mapping.

The incidence of Staphylococcus aureus bacteremia (SAB) is significantly higher in African American (AA) than in European-descended populations. We used admixture mapping (AM) to test the hypothesis that genomic variations with different frequencies in European and African ancestral genomes influence susceptibility to SAB in AAs. A total of 565 adult AAs (390 cases with SAB; 175 age-matched controls) were genotyped for AM analysis. A case-only admixture score and a mixed χ2(1df) score (MIX) to jointly evaluate both single-nucleotide polymorphism (SNP) and admixture association (P<5.00e-08) were computed using MIXSCORE. In addition, a permutation scheme was implemented to derive multiplicity adjusted P-values (genome-wide 0.05 significance threshold: P<9.46e-05). After empirical multiplicity adjustment, one region on chromosome 6 (52 SNPs, P=4.56e-05) in the HLA class II region was found to exhibit a genome-wide statistically significant increase in European ancestry. This region encodes genes involved in HLA-mediated immune response and these results provide additional evidence for genetic variation influencing HLA-mediated immunity, modulating susceptibility to SAB.

Musculoskeletal pain at various anatomical sites and socioeconomic position: Results of a national survey.

BACKGROUND: Prevalence of musculoskeletal pain according to sites of pain and associated factors in the community has not been thoroughly documented. The association between pain and socioeconomic position has been studied by several authors, but without details in most studies regarding sites of pain, whereas the relations with social position could differ according to the site of pain. The objective of this study was to explore these differences in the community in France. METHODS: The national Health and Occupational History survey was conducted in France in 2006 in subjects aged 20-74 years. Self-assessment of pain at various sites in the previous year was recorded. Five sites were considered here: back, neck, shoulder, upper limb, and lower limb. After a description of prevalence according to gender and age, the associations with socioeconomic position at the beginning of the subjects' working life, in seven categories, were studied with logistic models adjusted for age. The analyses were limited to those aged 30-74 years and were conducted separately for men and women. RESULTS: Of the 5520 males and 6643 females studied, prevalence was the highest for back pain (35% for males, 37% for females). Pain was globally more frequent for women. For all sites of pain an increase with age was significant for women. This was not observed in men for back pain (highest prevalence in the 40- to 49-year-old age group) or neck pain. Overall, prevalence of pain was the lowest for professionals (reference category in the analyses). For males, the first occupation as a farmer or blue-collar worker was associated with an increased prevalence for most sites of pain, with odds ratios close to 2. For females, prevalence was increased for more socioeconomic categories, as compared to professionals. Among the five sites, neck pain was an exception: for both men and women, no association was observed between neck pain and socioeconomic position. CONCLUSION: Although exploratory, these results are consistent with the available knowledge on occupational and personal risk factors for pain, which differ according to the site of pain. Other studies are needed to better understand the causal mechanisms underlying the associations observed.

Socioeconomic disparities in gait speed and associated characteristics in early old age.

BACKGROUND: A few studies have documented associations between socioeconomic position and gait speed, but the knowledge about factors from various domains (personal factors, lifestyle, occupation…) which contribute to these disparities is limited. Our objective was to assess socioeconomic disparities in usual gait speed in a general population in early old age in France, and to identify potential contributors to the observed disparities, including occupational factors. METHODS: The study population comprised 397 men and 339 women, aged 55 to 69, recruited throughout France for the field pilot of the CONSTANCES cohort. Gait speed was measured in meters/second. Socioeconomic position was based on self-reported occupational class. Information on personal characteristics, lifestyle, comorbidities and past or current occupational physical exposure came either from the health examination, from interview or from self-administered questionnaire. Four groups were considered according to sex-specific distributions of speed (the two slowest thirds versus the fastest third, for each gender). Logistic regression models adjusted for health screening center and age allowed to the study of cross-sectional associations between: 1- slower speed and occupational class; 2- slower speed and each potential contributor; 3- occupational class and selected potential contributors. The association between speed and occupational class was then further adjusted for the factors significantly associated both with speed and occupational class, in order to assess the potential contribution of these factors to disparities. RESULTS: With reference to managers/executives, gait speed was reduced in less skilled categories among men (OR 1.21 [0.72-2.05] for Intermediate/Tradesmen, 1.95 [0.80-4.76] for Clerks, Sale/service workers, 2.09 [1.14-3.82] for Blue collar/Craftsmen) and among women (OR 1.12 [0.55-2.28] for Intermediate/Tradesmen, 2.33 [1.09-4.97] for Clerks, 2.48 [1.18-5.24] for Sale/service workers/Blue collar/Craftsmen). Among men, occupational exposure to carrying heavy loads explained a large part of socioeconomic disparities. Among women, obesity and occupational exposure to repetitive work contributed independently to the disparities. CONCLUSIONS: This study suggests that some potentially modifiable occupational and personal factors explain at least part of the differences in gait speed between occupational classes, and that these factors differ between men and women. Longitudinal studies are needed to confirm and complement these findings.

Heavy smoking and lung cancer: are women at higher risk? Result of the ICARE study.

BACKGROUND: Whether women are more or equally susceptible to the carcinogenic effects of cigarette smoke on the lungs compared with men is a matter of controversy. Using a large French population-based case-control study, we compared the lung cancer risk associated with cigarette smoking by gender. METHODS: The study included 2276 male and 650 female cases and 2780 male and 775 female controls. Lifetime smoking exposure was represented by the comprehensive smoking index (CSI), which combines the duration, intensity and time since cessation of smoking habits. The analysis was conducted among the ever smokers. All of the models were adjusted for age, department (a regional administrative unit), education and occupational exposures. RESULTS: Overall, we found that the lung cancer risk was similar among men and women. However, we found that women had a two-fold greater risk associated with a one-unit increase in CSI than men of developing either small cell carcinoma (OR=15.9, 95% confidence interval (95% CI) 7.6, 33.3 and 6.6, 95% CI 5.1, 8.5, respectively; P<0.05) or squamous cell carcinoma (OR=13.1, 95% CI 6.3, 27.3 and 6.1, 95% CI 5.0, 7.3, respectively; P<0.05). The association was similar between men and women for adenocarcinoma. CONCLUSION: Our findings suggest that heavy smoking might confer to women a higher risk of lung cancer as compared with men.

Effects of agricultural pesticides on the health of Rana pipiens frogs sampled from the field.

There is evidence that over the last 30 years, there have been mass declines in diverse geographic locations among amphibian populations due to disease outbreaks. Multiple causes have been suggested to explain this increase in disease incidence. Among these, climate changes, environmental pollution and reduced water quality are gaining attention. Indeed, some chemicals of environmental concerns are known to alter the immune system. It is possible that exposure to these pollutants could alter the immune system of anurans and render them more susceptible to different pathogens. In this study, we sampled Rana pipiens in five different sites near St. Lawrence River (Quebec, Canada) during the months of July and September in 2001. Two of these sites were protected areas, in which low levels of pesticides were detected, while the remaining three sites were located in areas with intensive corn and soybeans cultivations. Our results demonstrated that frogs living in agricultural regions are smaller in size and weight than frogs living in areas with lower levels of pesticides at both sampling times. Moreover, we have observed a significant decrease in the number of splenocytes (cellularity) and the phagocytic activity in frogs sampled in impacted sites. Taken together, these results suggest that frogs living in agricultural regions might be more vulnerable to infections and diseases through their smaller size and alteration of their immune system. Our results also contribute to the overall discussion on factors involved in amphibian declines.

Male reproductive system defects and subfertility in a mutant mouse model of oculodentodigital dysplasia.

Oculodentodigital dysplasia (ODDD) is a dysmorphogenesis syndrome resulting from mutations in the GJA1 gene encoding the gap junction protein, connexin43 (CX43). In the testis this connexin localizes between Leydig cells, Sertoli cells and between Sertoli cells and germ cells. It is essential for Sertoli cell differentiation and spermatogenesis. This study explored male fertility in Gja1(Jrt) /+ mice which carry a dominant mutation that causes an amino acid substitution (G60S) in CX43. Gja1(Jrt) /+ mice mimic the phenotype of ODDD. Immunodetection methods revealed a reduction of both total CX43 and CX43 in membrane plaques in mutant testes. Correspondingly, intercellular coupling along the tubules was diminished as revealed by fluorescent dye transfer. Light and electron microscopy revealed loss of germ cells and sloughing of germ cells into the tubular lumen. There were also irregularities in size and shape of Sertoli cell nuclei. Analyses of cauda epididymal sperm indicated significant decreases in sperm count and sperm velocity parameters associated with sperm vigour, and significantly lower sperm head movement parameters associated with progressiveness. A significant decrease was also observed in total per cent motility. These results further confirm a critical role for CX43 in spermatogenesis and sperm maturation and support the possibility of subfertility in ODDD human males.

Clinical and dermoscopic features of 88 scalp naevi in 39 children.

BACKGROUND: Paediatric scalp naevi may represent a source of anxiety for practitioners and parents, as the clinical and dermoscopic features of typical naevi have yet to be defined. Prompted by concern about the large size, irregular borders and colour variation of scalp naevi, clinicians and parents may request unnecessary excision of these naevi. OBJECTIVES: To establish the typical clinical and dermoscopic patterns of scalp naevi in children younger than 18 years old to help optimize clinical care and management. METHODS: Scalp naevi were imaged with a camera (Canon Rebel, XSi; Canon, Tokyo, Japan) and dermoscopic attachment (Dermlite Foto, 30 mm lens; 3Gen, San Juan Capistrano, CA, U.S.A.) to the camera. The clinical and dermoscopic images were reviewed and analysed. Both acquired and congenital scalp naevi were included but were not further differentiated from each other. RESULTS: We obtained clinical and dermoscopic images of 88 scalp naevi in 39 white children. Two subjects had received chronic immunosuppressive medication. Nineteen children had a family history of melanoma. Boys (18/39 subjects, 46%) possessed 68% (60 naevi) of scalp naevi imaged. Younger (< 10 years old) subjects (24/39 subjects, 62%) possessed 42% (37 naevi) of scalp naevi. The main clinical patterns included eclipse (n=18), cockade (n = 3), solid brown (n=42) and solid pink (n=25) naevi. Solid-coloured naevi showed the following dermoscopic patterns: globular (57%), complex (reticular-globular) (27%), reticular (9%), homogeneous (6%) and fibrillar (1%). The majority of naevi had a unifying feature - perifollicular hypopigmentation, which caused the appearance of scalloped, irregular borders if occurring on the periphery, or variegation in pigmentation, if occurring within the naevi. CONCLUSIONS: Older subjects and boys tend to harbour a larger proportion of scalp naevi. The main clinical patterns include solid-coloured and eclipse naevi. The most common dermoscopic pattern of scalp naevi is the globular pattern. Perifollicular hypopigmentation is a hallmark feature of signature scalp naevi. Dermoscopy is a noninvasive tool in the evaluation of cutaneous melanocytic lesions in children and may decrease the number of unnecessary excisions.

Immunotoxicological effects of an activated-sludge-treated effluent on rainbow trout (Oncorhynchus mykiss).

Municipal effluents are often treated by biological processes designed to enhance natural biodegradation that introduce important changes to the local bacterial community and contaminant status. The purpose of this study was to examine the immunotoxicological effects of an activated sludge treated urban effluent on rainbow trout (Oncorhynchus mykiss). Trout specimens were exposed to increasing concentrations of the effluent at 0.1%, 1% and 10% v/v dilutions for 30 days at 15 degrees C. After the exposure period, the leukocytes were isolated from the anterior kidney and the following parameters were determined: phagocytic activity, lymphoblastic transformation and natural cytotoxic activity. The results revealed that phagocytic activity was not significantly affected by the biologically treated effluent. Natural cytotoxic activity was significantly increased at an effluent threshold concentration of 3% v/v at an effector/target cell ratio of 20:1 and 40:1. Stimulated lymphocyte T and B proliferation was significantly decreased at a threshold concentration of 0.3%. However, neither the unstimulated lymphocyte T nor lymphocyte B proliferation was significantly affected by effluent exposure. The results suggest that the activated-sludge-treated effluent increased cell-mediated cytotoxic activity with a concomitant decrease in cells responsible for antibody and cytokine production, indicating that the immune system of rainbow trout was directed towards the elimination of transformed cells, virus-infected cells and protozoan parasites at the expense of cytokine and antibody production.

Toxicokinetics of p-tert-octylphenol in male and female Sprague-Dawley rats after intravenous, oral, or subcutaneous exposures.

This study was undertaken to characterize the toxicokinetics of p-tert-octylphenol (OP), a weak estrogenic compound, in male and female rats. Male and female Sprague-Dawley rats were given a single dose of OP either by oral gavage (50, 125 or 250 mg/kg), by intravenous (iv) injection (2, 4, or 8 mg/kg), or by subcutaneous (sc) injection (125 mg/kg). In a repeated dosing experiment, rats were given OP (oral) daily (25, 50, or 125 mg/kg) for 35 d (female) or 60 d (male). Blood and tissue samples were collected and analyzed for OP content using gas chromatography with detection by mass spectrometry. Blood OP concentrations were generally higher in female than male rats following a single oral or sc administration but were similar following a single iv injection. Tissue OP concentrations were also higher in female than male rats following oral exposure, consistent with the faster metabolism of OP observed in male rat liver microsomes. After subchronic administration, blood OP concentrations were higher at the end of exposure for female (33 d) (2.26-fold, not significant) and male (57 d) (3.47-fold) rats than single dosing but there was no change in the tissue OP concentrations. Gender differences in tissue OP concentrations may contribute, in part, to gender differences in the toxicity of OP in rats. The fact that OP was found in all reproductive tissues confirms its potential for direct endocrine-like effects.

Relationship between total and high molecular weight adiponectin levels and plasma nonesterified fatty acid tolerance during enhanced intravascular triacylglycerol lipolysis in men.

CONTEXT: Increased plasma nonesterified fatty acid (NEFA) appearance during enhanced intravascular triacylglycerol (TG) lipolysis is a marker of metabolic adipose tissue dysfunction and may lead to the development of insulin resistance. The relationship between total and high molecular weight (HMW) adiponectin levels, NEFA appearance, and total TG lipolytic capacity has not been previously studied in humans. OBJECTIVES: Our objective was to determine whether total and HMW adiponectin plasma levels are associated with plasma NEFA level and appearance, and with total TG lipolytic rate during enhanced intravascular TG lipolysis in men. DESIGN: This was a cross-sectional metabolic study. SETTING: The study was performed at an academic clinical research center. PARTICIPANTS: There were 15 healthy men (mean +/- sd body mass index 25.5 +/- 4.7 kg/m(2)) aged 21-50 yr (mean +/- sd 31.1 +/- 10.2) without first-degree relatives with type 2 diabetes included in the study. INTERVENTIONS: Pancreatic clamps and iv infusion of stable isotopic tracers ([1,1,2,3,3-(2)H(5)]glycerol and [U-(13)C]palmitate) were performed, whereas intravascular TG lipolysis was clamped by iv infusion of heparin plus Intralipid at low (fasting) and high insulin levels. Total and HMW adiponectin levels were measured using an ELISA. MAIN OUTCOME MEASURES: Levels of total and HMW adiponectin, palmitate appearance (plasma palmitate appearance rate), and glycerol appearance (plasma glycerol appearance rate) were calculated. RESULTS: During heparin plus Intralipid infusion, total and HMW adiponectin was inversely correlated with plasma palmitate appearance rate (r = -0.65; P = 0.01), but this association was lost when expressed per nonlean weight. Adiponectin levels were positively associated with plasma glycerol appearance rate per nonlean weight (r = 0.71 and r = 0.66, respectively; P < or = 0.01). CONCLUSIONS: Increased adipose tissue mass likely explains the association between low adiponectin and reduced NEFA tolerance. Adiponectin level is a marker of total TG lipolytic rate per adipose tissue mass in men.

The effects of a primary-treated municipal effluent on the immune system of rainbow trout (Oncorhynchus mykiss): exposure duration and contribution of suspended particles.

Municipal sewage effluents are complex mixtures of contaminants known to disrupt both immune and endocrine functions in aquatic organisms. The present study sought to determine the impacts of municipal effluent on the immune systems of juvenile rainbow trout (Oncorhynchus mykiss), by exposing specimens to low concentrations (0.01%, 0.1%, 1% or 10%) of sewage effluent for periods of 28 or 90 days. The soluble and insoluble fractions of the effluent were also studied to assess the contribution of fractions rich in microorganisms and particles on fish immune systems. To this end, the trout were also exposed to soluble and insoluble fractions of the effluent for a period of 28 days. Immunocompetence was assessed by the following three parameters: phagocytosis, natural cytotoxic cells (NCC) and blastogenesis of lymphocytes under mitogen stimulation. Fish exposed to the 1% sewage effluent concentration for 28 days had enhanced phagocytic activity; at 90 days, phagocytic activity was reduced. T and B lymphocyte proliferation in fish from both groups was similarly stimulated. Phagocytosis and NCC activities were influenced more by the insoluble fraction than the soluble fraction of the effluent. Conversely, mitogen-stimulated T lymphocyte proliferation was enhanced in cells of fish exposed to the soluble fraction of the effluents, with a dampening effect on the insoluble (particulate) fraction of the effluent. In conclusion, the effects of the effluent and its fractions were higher at the cellular-mediated immunity level than at the acquired immunity level. Immunotoxicity data on the soluble fraction of the effluent were more closely associated to data on the unfractionated effluent, but the contribution of the particulate fraction could not be completely ignored for phagocytosis and B lymphocyte proliferation.

Effects of ozone, ultraviolet and peracetic acid disinfection of a primary-treated municipal effluent on the immune system of rainbow trout (Oncorhynchus mykiss).

Municipal sewage effluents are complex mixtures that are known to compromise the health condition of aquatic organisms. The aim of this study was to evaluate the impacts of various wastewater disinfection processes on the immune system of juvenile rainbow trout (Oncorhynchus mykiss). The trout were exposed to a primary-treated effluent for 28 days before and after one of each of the following treatments: ultraviolet (UV) radiation, ozonation and peracetic acid. Immune function was characterized in leucocytes from the anterior head kidney by the following three parameters: phagocytosis activity, natural cytotoxic cells (NCC) function and lymphocyte (B and T) proliferation assays. The results show that the fish mass to length ratio was significantly decreased for the primary-treated and all three disinfection processes. Exposure to the primary-treated effluent led to a significant increase in macrophage-related phagocytosis; the addition of a disinfection step was effective in removing this effect. Both unstimulated and mitogen-stimulated T lymphocyte proliferation in fish decreased dramatically in fish exposed to the ozonated effluent compared to fish exposed to either the primary-treated effluent or to aquarium water. Stimulation of T lymphocytes proliferation was observed with the peracetic acid treatment group. In conclusion, the disinfection strategy used can modify the immune system in fish at the level of T lymphocyte proliferation but was effective to remove the effects on phagocytosis activity.

Determination of p-tert-octylphenol in blood and tissues by gas chromatography coupled with mass spectrometry.

A sensitive and reproducible procedure using gas chromatography coupled with mass spectrometry is described for the determination of p-tert-octylphenol (OP), a persistent degradation product of alkylphenol ethoxylates that binds to the estrogen receptor in blood and tissues. The first step involved the extraction of blood (200 microL) or tissue homogenate (400 microL) with methyl tert-butyl ether, including p-tert-butylphenol (BP) as internal standard. After extraction, the sample was evaporated to dryness with a gentle stream of nitrogen at 45 degrees C, and OP and BP were derivatized with an acetylation reaction involving acetic anhydride and catalyzed by pyridine. Samples were then analyzed by a gas chromatograph equipped with a mass spectrometer (single ion monitoring) with a Varian VF-5ms capillary column. The limit of detection and the limit of quantification of the method in blood were 4.6 and 15.5 ng/mL, respectively. The linearity and reproducibility of the method were acceptable, with coefficients of variation of approximately 10% for blood and ranging between 9% and 27% for tissues. This method was applied to the determination of unchanged OP in blood and tissues obtained from Sprague-Dawley rats after oral and IV OP administration.

Impaired plasma nonesterified fatty acid tolerance is an early defect in the natural history of type 2 diabetes.

CONTEXT: Abnormal plasma nonesterified fatty acid (NEFA) metabolism may play a role in the development of type 2 diabetes. OBJECTIVES: Our objectives were to demonstrate whether there is a defect in insulin-mediated suppression of plasma NEFA appearance (RaNEFA) and oxidation (OxNEFA) during enhanced intravascular triacylglycerol lipolysis early in the natural history of type 2 diabetes, and if so, to determine whether other mechanisms than reduced insulin-mediated suppression of intracellular lipolysis are involved. DESIGN: These are cross-sectional studies. SETTING: The studies were performed at an academic clinical research center. PARTICIPANTS: Nine healthy subjects with both parents with type 2 diabetes (FH+) and nine healthy subjects with no first-degree relatives with type 2 diabetes (FH-) with similar anthropometric features were included in the studies. INTERVENTIONS: Pancreatic clamps and iv infusion of stable isotopic tracers ([1,1,2,3,3-(2)H5]-glycerol and [U-(13)C]-palmitate or [1,2-(13)C]-acetate) were performed while intravascular triacylglycerol lipolysis was simultaneously clamped by iv infusion of heparin plus Intralipid at low (fasting) and high insulin levels. Oral nicotinic acid (NA) was used to inhibit intracellular lipolysis. MAIN OUTCOME MEASURES: RaNEFA and OxNEFA were determined. RESULTS: During heparin plus Intralipid infusion at high plasma insulin levels, and despite similar intravascular lipolytic rates, FH+ had higher RaNEFA and OxNEFA than FH- (RaNEFA: 17.4+/-6.3 vs. 9.2+/-4.2; OxNEFA: 4.5+/-1.8 vs. 2.3+/-1.5 micromol/kg lean body mass/min), independent of NA intake, gender, age, and body composition. In the presence of NA, insulin-mediated suppression of RaNEFA was still observed in FH-, but not in FH+. CONCLUSIONS: Increased RaNEFA and OxNEFA during intravascular lipolysis at high insulin levels occur early in the natural history of type 2 diabetes.

Do workers with self-reported symptoms have an elevated risk of developing upper extremity musculoskeletal disorders three years later?

OBJECTIVES: Few prospective studies have evaluated outcomes of workers with self-reported symptoms of upper extremity musculoskeletal disorders (UEMSD). The objective was to study the three-year outcomes of workers with self-reported symptoms, with or without a positive physical examination. METHODS: In 1993-4, 598 subjects highly exposed to repetitive work filled out a Nordic-style questionnaire. They underwent a standardised physical examination at that time and again in 1996-7 by the same occupational physician. The three-year outcomes (based on physical examination) of workers with a self-administered questionnaire positive at baseline for UEMSD, with or without a positive physical examination, were studied. RESULTS: The three-year incidence rate was 44.1%; one third of these incident cases had self-reported symptoms in 1993-4. Workers with a positive questionnaire had a significantly higher risk of UEMSD at physical examination three years later (80.1% UEMSD cases with positive questionnaires n = 354, vs 44.2% cases without positive questionnaires n = 69, p<0.001). Moreover, workers with positive questionnaires but without UEMSD diagnosed in 1993-4 (n = 177) also had a significantly higher risk of UEMSD at physical examination three years later (60.5% cases with positive questionnaires n = 26, vs 38.8% cases without positive questionnaires n = 52, p = 0.01). Results were similar when gender and age were taken into account. CONCLUSION: Workers highly exposed to repetitive movements have a high risk of developing UEMSD and should be followed closely in surveillance programmes. Workers with self-reported symptoms without UEMSD diagnosed in physical examination represented only one third of new cases three years later. However, their risk of developing UEMSD was significantly increased, compared with those without symptoms.

Quebec neonatal mass urinary screening programme: from micromolecules to macromolecules.

The Quebec Mass Urinary Screening Programme, initiated in 1971, has resulted in the screening of more than 2,500,000 newborns in the province of Quebec for 25 inherited Mendelian disorders divided into two groups. The first group concerns urea cycle disorders (citrullinaemia, hyperargininaemia, argininosuccinic aciduria), ketotic hyperglycinaemia, and organic acidurias (methylmalonic aciduria, glutaric aciduria type I, etc.); the second group relates to disorders of amino acid metabolism (cystathioninuria, prolidase deficiency, etc.) and transport (Fanconi syndrome, cystinurias, Hartnup syndrome, etc.). The main goal of the Programme is to detect and prevent these genetic diseases, some detectable only in urine, before the onset of clinical symptoms. A multiplex thin-layer chromatography methodology was developed, in which metabolites in urine are resolved and visualized by the sequential application of four different reagents to detect aminoacidopathies and organic acidurias. The technique is simple, reproducible, inexpensive and rapid, allowing the analysis of 500 samples daily by a single technician. The voluntary compliance of the parents is excellent, averaging 90% per year. Over the years, we have established a dynamic process, developing techniques or new reagents to detect as many treatable disorders as possible, now evaluating macromolecules associated with lysosomal storage disorders, mainly globotriaosylceramide (Gb3) for Fabry disease. We present here the methodology, infrastructure in place, results and recent statistics of the well-established Quebec Mass Urinary Screening Programme. We also report a study by tandem mass spectrometric analysis of urinary Gb3 in Fabry disease for the follow-up and monitoring of Fabry patients, as well as for its possible application to mass and high-risk screening programmes.