Is there an optimal sampling time and number of samples for assessing exposure to fast elimination endocrine disruptors with urinary biomarkers?

In studies investigating the effects of endocrine disruptors (ED) such as phthalates, bisphenols and some pesticides on human health, exposure is usually characterized with urinary metabolites. The variability of biomarkers concentration, due to rapid elimination from the body combined with frequent exposure is however pointed out as a major limitation to exposure assessment. This study was conducted to assess variability of urinary metabolites of ED, and to investigate how sampling time and number of samples analyzed impacts exposure assessment. Urine samples were collected over 6 months from 16 volunteers according to a random sampling design, and analyzed for 16 phthalate metabolites, 9 pesticide metabolites and 4 bisphenols. The amount of biomarkers excreted in urine at different times of the day were compared. In parallel, 2 algorithms were developed to investigate the effect of the number of urine samples analyzed per subject on exposure assessment reliability. In the 805 urine samples collected from the participants, all the biomarkers tested were detected, and 18 were present in >90% of the samples. Biomarkers variability was highlighted by the low intraclass correlation coefficients (ICC) ranging from 0.09 to 0.51. Comparing the amount of biomarkers excreted in urine at different time did not allow to identify a preferred moment for urine collection between first day urine, morning, afternoon and evening. Algorithms demonstrated that between 10 (for monobenzyl (MBzP) phthalate) and 31 (for bisphenol S) samples were necessary to correctly classify 87.5% of the subjects into quartiles according to their level of exposure. The results illustrate the high variability of urinary biomarkers of ED over time and the impossibility to reliably classify subjects based on a single urine sample (or a limited number). Results showed that classifying individuals based on urinary biomarkers requires several samples per subject, and this number is highly different for different biomarkers.

Ultra performance liquid chromatography - tandem mass spectrometer method applied to the analysis of both thyroid and steroid hormones in human hair.

Hair is increasingly used as a biological matrix of interest for the assessment of hormone secretion over extended periods of time. This study described the development and the validation of a sensitive UPLC-MS/MS method for simultaneous analysis of steroid and thyroid hormones in human hair. The gradient designed in this method enables to obtain a satisfactory separation of 9 hormones of interest: cortisol, cortisone, THE, THF, α-THF, triiodothyronine (T3) and thyroxine (T4), estradiol, and testosterone. Several methodological parameters of extraction (such as the used of "cut hair" versus "pulverized hair", the extraction time, the incubation solvent purification on SPE column and hydrolysis) that may influence the determination of hormones levels in human hair, have thus been tested here. Therefore, the results obtained highlighted the necessity of using a C18 SPE purification method for the determination of both steroid and thyroid hormones in hair. This method allows reaching suitable levels of sensitivity for cortisol and cortisone since the results obtained pointed out concentration levels of cortisol in hair of volunteers similar to those observed in the literature. This method could also offer an important impact in the field of hormone analysis since it allows, for the first time, the quantification of both T3 and T4 in human hair.

Discrimination of various contributions to the absorbed dose in BNCT: Fricke-gel imaging and intercomparison with other experimental results.

A method is described for the 3D measurements of absorbed dose in a ferrous sulphate gel phantom, exposed in the thermal column of a nuclear reactor. The method, studied for Boron Neutron Capture Therapy (BNCT) purposes, allows absorbed dose imaging and profiling, with the separation of different contributions coming from different secondary radiations, generated from thermal neutrons. In fact, the biological effectiveness of the different radiations is different. Tests with conventional dosimeters were performed too.

Fibrillary glomerulonephritis in Castleman's disease.

Castleman's disease is an uncommon lymph node disorder which can be associated with renal disease. In this report we describe a patient with fever, weight loss, anorexia, increase in inflammatory proteins, anemia and nephrotic syndrome. Castleman's disease, plasma cell type, was diagnosed by histologic analysis after surgical excision of a pelvic lymph node. The disease was considered localized, since further investigations did not show any other pathologic mass. After resection of the pelvic lymphoid mass, clinical remission of systemic symptoms and laboratory abnormalities was observed, with the exception of the nephrotic syndrome. Renal biopsy was performed and showed a pattern compatible with fibrillary glomerulonephritis. Progressive decline in renal function was observed, despite immunosuppressive therapy.

Hypertension may be transplanted with the kidney in humans: a long-term historical prospective follow-up of recipients grafted with kidneys coming from donors with or without hypertension in their families.

In several genetic hypertensive rat strains, transplantation studies have established that the kidney carries at least a portion of the genetic message for hypertension. In man it has, of course, been more difficult to obtain clearcut results. This historical prospective observational study, double-blinded for knowledge of donors' and recipients' family history for hypertension, concerns 85 transplanted patients, not treated with cyclosporine and with stable renal function, followed up for an average of 8 yr. Both the donors' and the recipients' families were carefully characterized for presence or absence of hypertension. After transplantation, in recipients without hypertension in their own families, a kidney coming from a "hypertensive" family determines less withdrawal and more introduction of antihypertensive therapy (AHT) than a kidney from a "normotensive" family (odds ratio for AHT introduction 5.0, confidence interval, 1.4 to 17.8; P = 0.017). In recipients with familial hypertension, the origin of the kidney does not influence the prevalence of hypertension after transplantation. More detailed analyses show that, in recipients without familial hypertension, the transplantation of a "hypertensive" kidney determines a tenfold larger increase in the requirement of antihypertensive therapy than the transplantation of a "normotensive" kidney, to obtain a similar blood pressure control (P = 0.003). This results is confirmed by the analysis of time-profile trends for antihypertensive therapy, adjusted for missing data, in the most clinically stable period (2nd to 10th yr after transplantation). The transmission of familial hypertension with the kidney is thus seen only in recipients coming from "normotensive" families, because a familial tendency for hypertension blunts the effect of receiving a "hypertensive" kidney.

Psychiatric disorder in a familial 15;18 translocation and sublocalization of myelin basic protein of 18q22.3.

Two related patients with similar clinical features consisting of a few dysmorphic signs and psychiatric disturbance were reported to have a partial trisomy of chromosomes 15(pter-q13.3) and 18(q23-qter) deriving from a familial translocation t(15;18). One patient is affected by bipolar disorder and the other by schizoaffective disorder. Both cases have a predominantly affective course; nevertheless, a clear diagnosis is difficult in the first patient, who is 15 years of age, and only a longitudinal course will allow us to establish a definite diagnosis. The possibility that these two pathologies belong to a single category is discussed, and the presence of a susceptibility locus on chromosome 18 is hypothesized. Cytogenetic data, FISH, and DNA studies indicate that the myelin basic protein (MPB) gene is not involved in the translocation, and localize it centromeric to the breakpoint on chromosome 18(q22.3). Thus, it is unlikely to be involved in the disease.

Linear sebaceous nevus syndrome: report of a patient with unusual associated abnormalities.

A 9-year-old girl was diagnosed as having a linear sebaceous nevus syndrome (LSNS). The nevus sebaceus was located on the face, and the girl also had nevoid hypertrichosis on the neck, sensorineural deafness, partial anodontia, blocked tear ducts, labiopalatoschisis, and an area of micropolygyria in the left encephalic (cerebral) hemisphere. Electroencephalographic alterations were detected, but they were not accompanied by a history of seizures; furthermore, the child was not mentally retarded. This phenotypic pattern of LSNS is unusual for the rarity of associated abnormalities.

Nonacidotic kidney proximal tubulopathy with absorptive hypercalciuria.

We studied three patients with proximal tubulopathy characterized by defective reabsorption of phosphate, glucose, amino acids, urate, and low molecular weight proteins. This tubulopathy differs from Fanconi syndrome in that the patients had normal plasma bicarbonate and absorptive hypercalciuria associated with increased 1,25-dihydroxyvitamin D levels. The youngest patient was rachitic and may be classified with previously described patients, whereas the other two patients presented with nonrachitic osteopenic bone disease and their tubulopathy started during adult life. Kidney defects appeared sequentially in one of the nonrachitic patients. The two brothers of the youngest patient had similar kidney and bone disturbances. One of the other two patients had a brother with similar kidney reabsorption defects; an additional brother was probably affected and a sister presented with glycosuria, but no other reabsorption defects. The findings in these two families suggest a genetic transmission of proximal tubulopathy. The third case was sporadic. Renal histology of the three patients showed a great number of giant cells in the tubular lumen. We conclude that, at least in our adult patients, tubulopathy may represent a new entity among the proximal tubular dysfunction cases described to date. The features of this proximal defect suggest that it may be caused by a selective alteration of luminal cell membrane transport of phosphate, glucose, amino acids, urate, and proteins in the presence of a normal sodium gradient across the tubular cell membrane.

New variant of chromosome 11.

An additional C-positive band in the centromeric region (p11) was observed in a man. By GTG- and RBA-techniques it was positively stained but by QFQ-technique the staining intensity was negative. Although he was identified through fetal loss in his wife, it apparently represents a familial variant whose clinical significance is unknown.

Characterization of a deleted Y chromosome in a male with Turner stigmata.

A 46,X,+mar karyotype was detected in an 11-year-old male with a clinical picture characterized by obesity, short stature, bilateral cryptorchidism and coarctation of the aorta. The presence of ZFY and SRY genes was demonstrated by PCR amplification, and the origin of the marker chromosome from a deleted Y chromosome was analyzed by in situ hybridization. The proximal limits of a deletion in Yq were defined by the absence of Southern blot hybridization signals upon probing with Yq11 markers. Cytogenetics and molecular methods taken together indicate a deletion in q11.21. In addition, the loss of Yp subtelomeric sequences was suggested by the analysis of Southern blots hybridized with a 29A24 (DXYS14) probe and by the presence of coarctation of the aorta tentatively localized in Yp. The karyotype of the patient was suggested to be: 46,X,del (Y) (p11.3-q11.21).

Effect of cyclosporin A on renal cortical resistances measured by color Doppler flowmetry on renal grafts.

Doppler spectra were recorded at different cyclosporin A (CSA) levels (trough and peak) in 30 stable renal-transplanted outpatients: 15 with unimpaired renal function (plasma creatinine < 150 mumol/l) and 15 with renal impairment (plasma creatinine 150-350 mumol/l). Pulsatility (PI) and resistive indexes (RI) have been measured in the renal artery at the hilum and in the renal cortex. RI and PI were markedly increased (p < 0.0001) in the cortex at peak time while in the renal artery no significant changes were observed. These variations were statistically related with CSA blood levels (PI = p < 0.02; r = 0.54, RI = p < 0.05; r = 0.45). These effects were also found in the presence of renal damage. CSA dose-dependently reduces cortical blood flow, causing a persistent arteriolar vasoconstriction and a reduction in diastolic flow. This effect can be measured in man in a noninvasive and repeatable way using color Doppler sonograms.

Localization of cloned human DNA sequences and analysis of chromosomal alterations by in situ hybridization.

The in situ hybridization technique was used for the localization on human chromosomes of single-copy and repeated sequences and, in addition, for the characterization of altered human chromosomes. Two anonymous clones, single or low-copy, obtained from a human X chromosome library were localized on the distal part of the long arm and in the paracentromeric region of X chromosome, respectively. A genomic fragment of the single-copy thyroglobulin (TG) gene was used to confirm the localization on the distal part of the long arm of chromosome 8. The localization and distribution on human chromosomes of the glyceraldehyde-3-phosphate dehydrogenase (GAPD) multigene family obtained by in situ hybridization and by somatic cell hybrids were compared. A phosphoglycerate kinase (PGK) c-DNA clone, which detects genic and pseudogenic sequences on the X chromosome, was used for the characterization of three small ring markers present in unrelated female patients.

Cyclosporine renal cortical vasoconstriction measured by colour Doppler imaging in kidney transplantation.

Important side-effects limit the use of cyclosporine A (CSA), the most insidious of which is nephrotoxicity, which manifests as a preglomerular arteriolar vasoconstriction causing a reduction in glomerular filtration rate (GFR) and renal plasma flow (RPF). This condition is initially purely functional, but with time can become anatomic and irreversible. In clinical practice we lack suitable methods for evaluating CSA vasoconstriction. Our present knowledge is based on indirect information obtained from repeated measurerments of plasma creatinine levels and from blood concentrations of the drug. Sometimes more complex and non-routine tests, such as the evaluation of GFR and RPF, or invasive methods, such as renal biopsy, are also employed. In this study we used the colour-Doppler technique to measure directly the vascular effects of CSA in patients with transplanted kidneys, evaluating changes in blood flow at the hilus and on the cortex of the kidney when the drug was at trough or peak levels.

Sublocalization of von Willebrand factor pseudogene to 22q11.22-q11.23 by in situ hybridization in a 46,X,t(X;22)(pter;q11.21) translocation.

The von Willebrand factor pseudogene, previously mapped to chromosome 22, was sublocalized by in situ hybridization using as probe a von Willebrand factor cDNA fragment completely contained in the pseudogenic region. Chromosome spreads were from a patient carrying a unique balanced de novo translocation 46,X,t(X;22)(pter;q11.21). Silver grain analysis indicated that the human von Willebrand factor pseudogene is located on 22q,11,22-q11,23, a region relevant for several somatic and constitutional chromosomal alterations.