Central nervous system dysfunction due to lead exposure.

Central nervous system dysfunction was investigated in workers at a secondary lead smelter by means of performance tests. Correlations between test scores and zinc protoporphyrin levels, a biological indicator of lead toxicity, are statistically significant. This correlation should prove to be useful in current efforts to evaluate effects of lead exposure.

Fluorescence polarization study of human erythrocyte membranes with 1-phenyl-3-(2-naphthyl)-2-pyrazoline as orientational probe.

The emission and polarization spectra of 1-phenyl-3-(2-naphthyl)-2-pyrazoline (PNP) in various environments were studied. Compared to the widely used orientational membrane probe 1,6-diphenylhexatriene (DPH), PNP is five times less photolabile and since its fluorescence emission maximum is at longer wavelengths (lambda max approximately 445 nm), it is more suitable for use with intact erythrocytes. The limiting fluorescence anisotropy of PNP is 0.385. In erythrocyte ghosts, the steady-state emission anisotropy of PNP is a decreasing formation of wavelength and its temperature dependence parallels that of DPH, dropping from 0.298 at 2 degrees C to 0.185 at 38 degrees C when averaged between 420 and 470 nm.

The distribution of intracellular calcium chelator (fura-2) in a population of intact human red cells.

Using quantitative fluorescence microscopy of red cells loaded non-disruptively with 1-2.5 mmol/l cells of fura-2, we examined the distribution of the incorporated free chelator among and within individual cells. Cytoplasmic hemoglobin quenched the effective fluorescence yield of fura-2 by a factor of about 100. All red cells were found to fluoresce upon excitation at 380 nm, and the fluorescence intensities they emitted at 510 nm were approximately +/- 20% about the mean intensity, indicating a fairly uniform distribution of incorporated chelator among the cells. Red cells loaded with these high levels of fura-2 retained their biconcave shape, and a comparison between their transmission images at 415 nm and their fura-2 fluorescence images suggests that the concentration of fura-2 was also uniform throughout the cytosol. These results validate assumptions made in earlier experiments with non-fluorescent incorporated Ca2+ chelators, and demonstrate the feasibility of fura-2 and Ca2+ imaging of intact red cells, despite considerable quenching of probe fluorescence by hemoglobin.

Representation and high-quality annotation of the Physcomitrella patens transcriptome demonstrates a high proportion of proteins involved in metabolism in mosses.

To gain insight into the transcriptome of the well-used plant model system Physcomitrella patens, several EST sequencing projects have been undertaken. We have clustered, assembled, and annotated all publicly available EST and CDS sequences in order to represent the transcriptome of this non-seed plant. Here, we present our fully annotated knowledge resource for the Physcomitrella patens transcriptome, integrating annotation from the production process of the clustered sequences and from a high-quality annotation pipeline developed during this study. Each transcript is represented as an entity containing full annotations and GO term associations. The whole production, filtering, clustering, and annotation process is being modelled and results in seven datasets, representing the annotated Physcomitrella transcriptome from different perspectives. We were able to annotate 63.4 % of the 26 123 virtual transcripts. The transcript archetype, as covered by our clustered data, is compared to a compilation based on all available Physcomitrella full length CDS. The distribution of the gene ontology annotations (GOA) for the virtual transcriptome of Physcomitrella patens demonstrates consistency in the ratios of the core molecular functions among the plant GOA. However, the metabolism subcategory is over-represented in bryophytes as compared to seed plants. This observation can be taken as an indicator for the wealth of alternative metabolic pathways in moss in comparison to spermatophytes. All resources presented in this study have been made available to the scientific community through a suite of user-friendly web interfaces via www.cosmoss.org and form the basis for assembly and annotation of the moss genome, which will be sequenced in 2005.

Rapid fluorometric assay of bilirubin and bilirubin binding capacity in blood of jaundiced neonates: comparisons with other methods.

The concentrations of total blood bilirubin, albumin-bound bilirubin, and the reserve and total bilirubin binding capacities of 35 neonatal blood samples (28 patients) were determined by automated front-face fluorometry ((hematofluorometer). These values were compared to results of diazo determinations, Sephadex gel filtration, and peroxidase-oxidation methods. Total blood bilirubin level by fluorometry agreed well with the total plasma bilirubin level by diazotization (r = .96, sigma = 1.7 mg/100 ml). Albumin-bound bilirubin concentrations by fluorometry also correlated well with diazo values (r = .95, sigma = 1.9 mg/100 ml) and were slightly lower than the total blood bilirubin concentrations. Values for total bilirubin binding capacity determined by fluorometry agreed well with results obtained for the same specimens by Sephadex gel filtration (n = 28, r = .97, sigma = 1.8 mg/100 ml) and by peroxidase-catalyzed oxidation (n = 25, r = .97, sigma = 1.7 mg/100 ml). The agreement among the results obtained by the three methods indicates a well-defined in vitro end point at which available primary or "tight" binding sites on albumin are saturated with bilirubin. In this clinical experience the coefficient of variation of results with the hematofluorometer was 8.4% for total blood bilirubin and 6.5% for total binding capacity. A comparison of "sick" with "well" infants revealed that the fraction of bilirubin not bound to albumin was significantly different for these two groups. The assays made with the hematofluorometer are quick (10 to 15 minutes) and require only a small quantity (approximately 150 microliters) of blood.

A rapid fluorometric method for determining bilirubin levels and binding in the blood of neonates: comparisons with a diazo method and with 2-(4'-hydroxybenzene)azobenzoic acid dye binding.

A simple, rapid fluorometric method for determining the albumin-bound bilirubin concentration, total blood bilirubin concentration, and the bilirubin reserve-binding capacity of albumin was clinically evaluated using blood specimens from 79 neonates. This study showed that these bilirubin determinations, made by means of the Bell Laboratories hematofluorometer, correlated well with plasma bilirubin levels obtained by a diazotization (Jendrassik-Grof) method. Hematofluorometer reserve-binding capacities correlated very well with 2-(4'-hydroxybenzene)azobenzoic acid (HABA) dye reserve-binding capacities for specimens of artificially jaundiced adult blood. For specimens of neonatal blood the HABA dye reserve capacity was, on the average, higher than the hematofluorometer reserve-binding capacity, particularly for specimens from low-birth-weight babies (less than 2,000 gm). Comparison of HABA reserve capacity and hematofluorometer reserve capacity for high-birth-weight babies (greater than 2,000 gm) gave data very similar to those for adult blood specimens. The specific bilirubin-binding capacity of albumin was found to be greater for infants whose birth weight exceeded 2,000 gm than for the lower birth weight group. The total blood bilirubin concentration obtained by the hematofluorometer is shown to be significantly higher than the concentration of bilirubin bound to albumin, an indication of other important compartments of bilirubin in blood.

Hemoglobin, serum iron, and zinc protoporphyrin in lead-exposed workers.

In a previous study of secondary lead smelter workers (males), a significant prevalence of low hemoglobin levels (less than 14 g/100 ml) was found; a statistically significant negative correlation between hemoglobin and zinc protoporphyrin was also detected. In the present study serum iron (Fe) levels and total iron binding capacity (TIBC) were included in the investigation of 111 secondary lead smelter workers and 37 nonexposed controls. The distribution and mean values of serum iron and TIBC were found to be in the normal range in the lead exposed workers; there was no significant difference when compared to the control population. There was no significant correlation between blood lead or zinc protoporphyrin and serum iron, TIBC and Fe/TIBC. A statistically significant negative correlation between hemoglobin and blood lead levels was found; the correlation between hemoglobin and zinc protoporphyrin reached a much higher level of significance. The results support the view that anemia (low hemoglobin levels) in lead exposed male workers is related to the heme synthesis inhibiting effects of lead, as reflected by elevated zinc protoporphyrin levels, and is not due to iron deficiency.

The lateral fluidity of erythrocyte membranes. Temperature and pressure dependence.

The pressure and temperature dependence of the lateral and rotational fluidity of erythrocyte membranes was investigated by inserting the excimeric membrane probe 1'-pyrenedodecanoic acid (PDA) into the membranes of intact cells and measuring the probe excimer formation rate and the steady-state polarization of the monomer at pressures up to 2000 atm (2 kbar). At that pressure the lateral diffusivity of PDA was found to decrease by a factor of 10 and its emission anisotropy by a factor of 5 at 22 degrees C. At atmospheric pressure, the local lateral diffusion coefficient of PDA at 2 and 33 degrees C is 1.5 and 4.3 x 10(-8) cm2 s-1, respectively. The activation energy for probe translation was found to decrease from 6 to 3 kcal M-1 in going from atmospheric pressure to 2 kbar, while the entropy decreased by approx. 15 cal M-1 K-1, indicating greater lipid order at the high pressure. The experimental data are consistent with a 'free-area' model for the membrane, analogous to the free-volume model for nonassociated liquids. The lateral diffusivity of PDA was found to be proportional to the free membrane area and linear extrapolation to zero diffusivity indicates that at atmospheric pressure, the fractional free area of the erythrocyte membrane is 6%.

[Supraventricular tachycardia induced by effort and by catecholamines]. / Tachycardie supraventriculaire induite par l'effort et les catécholamines.

The role played by catecholamines in the initiation of certain forms of ventricular tachycardia is now recognised. On the other hand, a similar predominant or exclusive mechanism has not been demonstrated in supraventricular tachycardia. We observed a rate case of reproducible attacks of junctional tachycardia on effort in a 45 year old man. This patient had experienced attacks of tachycardia on effort for a number of years, stopping about 10 minutes after the end of effort. An exercise stress test performed for an anginal attack, induced a narrow complex tachycardia at 270/min at the first minute of the recovery period which terminated spontaneously 18 minutes later after a brief episode of atrial fibrillation. During a second exercise stress test, an episode of tachycardia at 250/min was recorded at the second minute of recovery, lasting 11 minutes. Investigations showed a retrograde concealed septal bundle of Kent activated retrogradely during reciprocating tachycardia. A similar form of tachycardia was induced by an injection of isoproterenol. The adrenergic mechanism of the arrhythmia led to the prescription of a beta-blocker (propranolol 120 mg/day), which effectively prevented clinical tachycardia and the forms of tachycardia induced by ergometric tests 15 days and 3 months after the initiation of treatment.

Lead effects among secondary lead smelter workers with blood lead levels below 80 microgram/100 ml.

A subgroup of workers from a secondary lead smelter was defined to include those with blood lead levels not exceeding 80 microgram/100 ml and with no past history of elevated blood lead. Central nervous system symptoms (tiredness, sleeplessness, irritability, headache) were reported by 55% of the group and muscle and joint pain by 39%. Zinc protoporphyrin (ZPP) levels were elevated in 71% of cases. Low hemoglobin levels (less than 14 gm/100 ml) were found in more than a third of the workers. While BUN and creatinine were mostly in the normal range, there was nevertheless a correlation between ZPP and both BUN and creatinine. Reduced nerve-conduction velocities were present in 25% of the group; this was not significantly different from findings in a control group. The data indicate that a blood level of 80 microgram/100 ml is an inappropriate biological guide in the prevention of lead disease.

Effects of silicon, fluoride, etidronate and magnesium on bone mineral density: a retrospective study.

A retrospective study of bone mineral density (BMD) changes was performed in 53 osteoporotic women prior to carrying out a prospective study. Comparisons between BMD of controls (n = 16) and treated groups over a 14-22 month period showed that fluoride (n = 10) induced a significant (P < 0.05) increase in vertebral and a slight decrease in femoral BMD, whereas silicon (n = 8) induced a significant (P < 0.05) increase in femoral BMD. Etidronate (n = 13) and, to a lesser extent, magnesium (n = 6), induced a slight although statistically non-significant increase in vertebral BMD.

Absence of correlation between magnesium and riboflavin status.

Erythrocyte magnesium and glutathione reductase activity coefficient (EGR-AC), reflecting vitamin B-2 status, were assessed in 11 athletes, 20 patients with fibromyalgia, 18 patients with hypothyroidism, and 13 controls. No correlation was demonstrated between erythrocyte magnesium and EGR-AC.

Selenium and magnesium status in fibromyalgia.

Muscle pain has been associated with magnesium (Mg) and selenium (Se) deficiency: magnesium and selenium status were investigated in fibromyalgia (FM). Erythrocyte (E), leucocyte (L) and serum (S) magnesium, serum selenium and zinc, and vitamin B1, B2, A or E status were assessed in 22 patients with fibromyalgia and in 23 age-matched healthy controls. LMg is significantly increased (P < 0.05) and EMg slightly decreased in fibromyalgia. These magnesium abnormalities are associated with previously-reported impairment of thiamin metabolism. Antioxidant status (as well as plasma malondialdehyde) is unchanged in fibromyalgia and serum selenium levels, slightly but not significantly correlated with serum magnesium, is normal.

Effects of magnesium, high energy phosphates, piracetam and thiamin on erythrocyte transketolase.

Erythrocyte transketolase activity coefficient (ETK-AC) and affinity for coenzyme (Km TPP) were assessed in 50 patients with transketolase abnormalities such as fibromyalgia or senile dementia of Alzheimer's type, before and after magnesium (Mg), thiamin+pyridoxine (B1,B6), high energy phosphates (HEP) (phosphocreatinine of adenosine triphosphate), and piracetam. Compared to 12 untreated patients, ETK-AC was significantly decreased with B1,B6 (P < 0.05, n = 10); Km-TPP was significantly decreased with HEP (P < 0.05, n = 20) and piracetam (P < 0.01, n = 5). In nine other patients treated with HEP + B1,B6 + magnesium, ETK-AC and Km TPP were both significantly decreased.

Protein peroxidation, magnesium deficiency and fibromyalgia.

Lipid and protein peroxidations were investigated in female patients with magnesium deficit (MD), fibromyalgia (FM) and age matched controls: malondialdehyde and protein carbonyls (PC), as well as serum, leucocyte and erythrocyte magnesium (EMg) were assessed in 20 controls, 25 FM and 16 MD patients. MDA are unchanged in MD and FM. PC are significantly increased (P < 0.01) in FM. EMg is significantly decreased in MD. There is a slight, but not significant, negative correlation between PC and EMg, in controls and MD. Protein peroxidations are demonstrated in FM. Further studies are needed in MD.

[Clinical evaluation of fibromyalgia]. / Evaluation clinique de la fibromyalgie.

OBJECTIVES: Fibromyalgia is characterized by diffuse, persistent and unexplained muscle pain associated with tenderness (mechanical allodynia) and unspecific symptoms. Diagnosis criteria as well as pathophysiological mechanisms are still unclear, justifying appropriate questionnaires and clinical investigations. ACTUAL TOPICS: Several questionnaires including visual analogic scales with respect to pain, fatigue, sleep or mood disorders have been used in fibromyalgia such as Fibromyalgia Impact Questionnaire (30 items) and the European List for Fibromyalgia Evaluation (53 items). Similarly several methods have been proposed to evaluate tenderness in fibromyalgia patients: The study of tender points involves their number (normal value < 4/18), or their pain mean intensity score and the sum of their sensitivities defining the tender point index (normal value < 11/72); The average pain threshold (normal value > 4 kg/cm(2)) is more precise, requiring sophisticated devices (mechanical algometers) and physician training; Less complex than pain threshold measurement, more reliable than the tender points number or index, the tensiometer induced myalgia (normal value > 210 mmHg) is probably a promising new alternative way to screen for fibromyalgia. PROSPECTS: Even if further studies are needed, diagnosis approach of fibromyalgia could be improved by new tools such as the European List for Fibromyalgia Evaluation and algotensiometry.

[Sleep apnea and fibromyalgia: the absence of correlation does not indicate an exclusive central hypothesis]. / Apnées du sommeil et fibromyalgie: l'absence de corrélation n'est pas en faveur de l'hypothèse centrale exclusive.

Fibromyalgia (FM) is a chronic painful syndrome characterized by widespread aching and points of tenderness, changed perception of pain and reduced brain serotonin. Abnormal EEG patterns have been reported in this condition. A study of FM occurrence in subjects with sleep abnormalities demonstrated by polysomnography was performed. Fifty patients (group 1:29 with sleep apnea and group 2:21 with poor sleep without sleep apnea) and 31 control subjects (without any sleep abnormalities) were submitted to the same clinical research of FM (ACR criteria). There was one 1 FM in group 1 (3.4%), one FM in group 2 (4.7%), and one FM in control group (3.2%). Sleep abnormalities and particularly sleep apnea are not significantly associated with FM. Other pathophysiological factors than central mechanisms are probably involved in the pathogenesis of FM.

[Erythrocyte transketolases and Alzheimer disease]. / Transcétolases érythrocytaires et maladie d'Alzheimer.

Abnormalities of thiamin metabolism have been reported in senile dementia of Alzheimer's type (SDAT). Transketolases (TK) were studied in 21 patients with SDAT, 24 age-matched controls and 12 chronic alcoholics. Erythrocytes were assessed for their TK activity coefficient (TK-AC, normal value 8.4 +/- 12.6%) and affinity for thaimin pyrophosphate (Km TPP, normal value 17.8 +/- 8.3 mumol). Comparison between study groups and controls demonstrated increased TK-AC in SDAT (16.6 +/- 15.7%, P < 0.05) and chronic alcoholism (43.4 +/- 40.6%, P < 0.05), and increased Km TPP (38.3 +/- 25.2 mumol, P < 0.01) in SDAT only. These findings suggest structural abnormalities of TK rather than vitamin B1 deficiency in SDAT.

Lead and wine. Eberhard Gockel and the colica Pictonum.

Thecolica Pictonum or colic of Poitou, under these and many other names, was a frequent, widespread, and deadly disease from Roman times until the eighteenth century. Its unique pathognomonic, notably a severe colic succeeded by paralysis and other central nervous system dysfunction, makes it possible to identify the disease with certainty as chronic lead disease, usually caused by the ingestion of lead-adulterated wines. The custom of sweetening and preserving sour wines with lead-containing additives is traced to the Romans. They had made the empirical discovery that sapa, a syrup prepared by concentrating must in a lead vessel, kept wine from spoiling and that it had, moreover, an agreeable flavour.Reports of outbreaks of the colica Pictonum appear in the medical literature from Roman times, but the correct aetiology of the disease was not discovered until the seventeenth century following a series of outbreaks in Southern Germany which were related to unfavourable climatic and political conditions. The connexion between the disease and prevailing methods for "correcting" wines was drawn in 1696 by Eberhard Gockel, then the city physician of Ulm. This achievement can be traced to his familiarity with Samuel Stockhausen's work on plumbism among miners and potters, as well as to the favourable epidemiological situation presented by Gockel's monastic patients. From the literary evidence assembled here and from experimental determinations of the lead content of sapa and similar concentrates, it is possible to estimate the lead levels and toxicity of wines from various eras. The levels range up to 80 mg/l and make it apparent that many wines were sufficiently toxic to account for the incidence and severity of the colica Pictonum. Explanations for the disastrous persistence of the colic of Poitou are discussed, as are the similarities between Gockel's approach and the methods of modern environmental medicine.