101 Heifer plane of nutrition during the prepubertal phase modifies reproductive development in male fetuses

Maternal nutritional perturbation during gestation influences fetal development which, in turn, can affect postnatal growth, gonad development, gamete quality, and health of the offspring. The objective of this study was to determine whether maternal diet during the pre-pubertal phase would induce modifications in future male fetal reproductive development. Angus×Holstein-Friesian heifers (n=80) with a mean (±s.d.) age of 141±8d and bodyweight (BW) of 119±23kg had unrestricted access to a perennial ryegrass dominated sward supplemented with either 0.5kg of concentrate daily to achieve an average daily gain (ADG) of 0.50kg (moderate, MOD) or concentrate ad libitum to achieve an ADG of >1.0kg (high, HI). Heifers were offered these divergent dietary regimens from 4.5 to 8.5 months of age, after which they were all offered a moderate plane of nutrition. Heifers were bred to a synchronised oestrus at a mean age of 502±8.2d and mean BW of 360±46.7kg using semen from a single proven sire. Transrectal uterine ultrasonography was carried out 63 days post-AI to determine pregnancy and fetal sex; a cohort of heifers reflective of group average BW and age and carrying male fetuses were slaughtered on Day 100 of gestation (HI: n=10; MOD: n=12). Fetal crown–rump length and weight were recorded. One testis was snap frozen for RNA sequencing and the other was processed for stereology. Mean (±s.d.) fetal crown–rump length and weight were 19.5±0.69cm and 314.6±33.6g, respectively, and did not differ between groups. RNA sequencing revealed 45 differentially expressed genes (DEGs) between groups, 44 of which were upregulated in the HI group. A total of 29 biochemical pathways were identified as significantly enriched (P<0.05), six of which were predicted to be involved in the development of the reproductive tract based on several DEGs. Histological analysis revealed greater (P<0.05) fetal testicular interstitial tissue density in the MOD group and a strong tendency towards increased seminiferous tubule density (P=0.06) in the HI group. In conclusion, offering a high plane of nutrition during the prepubertal period not only increases the rate of sexual development in the heifer but also induces latent in utero modifications to the testicular development of their subsequent male progeny. The consequences for postnatal development of male progeny remain to be elucidated. This research was supported by Science Foundation Ireland (16/IA/4474).

Ultrasonographic measures of body fatness and their relationship with plasma levels and adipose tissue expression of four adipokines in Welsh pony mares

Obesity is responsible for metabolic dysregulations that alter fertility and induce pathologies. The objectives of the present study were to validate a reliable method for the evaluation of body fatness in mares and to associate the body fat estimation data to metabolic changes, including adipokines at the plasma and adipose tissue levels. To reach this purpose, animals were subjected to two extreme breeding conditions to study the variation of morphological, ultrasound, and physiological parameters. Twenty Welsh mares were followed up monthly from April to October before and after animals were moved outdoors to grasslands. Body weight (BW), body length (BL), height at the withers (HW), thoracic perimeter (TP), 5-point body condition score (BCS), and subcutaneous fat thickness (SFT) at the level of the shoulder, the lumbar region, and the rump, measured by ultrasonography, and plasma and adipose tissue metabolic indicators were assessed in parallel. Statistical analysis was performed using a linear mixed-effects model, whereas Pearson tests were used for the analysis of the correlations between the different parameters. Although mean BW did not increase significantly (P = 0.0940), TP (P = 0.0002) and BCS (P < 0.0001) increased during the study period. Ultrasonographic examination of subcutaneous adipose tissue showed an increase in SFT at the level of the shoulder (P < 0.0001), lumbar region (P < 0.0001), and rump (P < 0.0001). Plasma concentrations of nonesterified fatty acids (P < 0.0001), phospholipids (P < 0.0001), and cholesterol (P < 0.0001) increased significantly, whereas triglycerides (P < 0.0001) decreased significantly during the study period. Although both plasma concentrations and adipose tissue expression of leptin (P < 0.0001) and resistin (P < 0.0001) increased significantly, adiponectin (P < 0.0001) significantly decreased and visfatin remained unchanged (P = 0.8401). Expression of adipokine receptors studied showed the opposite pattern compared with their ligand. Ultrasonographic measurements of subcutaneous adipose tissue thickness at the shoulder, lumbar region, and rump are relevant indicators of fatness related with adipokine plasma concentrations and expression of adipokine-related receptors in adipose tissue, and particularly highlight seasonal effects.

Role of early life nutrition on regulating the hypothalamic–anterior pituitary–testicular axis of the bull

The objective of this study was to examine the effect of nutrition during the first 18 weeks of life on the physiological and transcriptional functionality of the hypothalamic (arcuate nucleus region), anterior pituitary and testes in Holstein–Friesian bull calves. Holstein–Friesian bull calves with a mean (±S.D.) age and bodyweight of 19 (±8.2) days and 47.5 (±5.3) kg, respectively, were assigned to either a HIGH (n = 10) or LOW (n = 10) plane of nutrition, to achieve an overall target growth rate of 1.2 or 0.5 kg/day, respectively. At 126 ± 1.1 days of age, all calves were euthanised. Animal performance (weekly) and systemic concentrations of metabolic (monthly) and reproductive hormones (fortnightly) were assessed. Testicular histology, targeted gene and protein expression of the arcuate nucleus region, anterior pituitary and testes were also assessed using qPCR and immunohistochemistry, respectively. The expression of candidate genes in testicular tissue from post pubertal 19-month-old Holstein–Friesian bulls (n = 10) was compared to that of the 18-week-old calves. Metabolite and metabolic hormone profiles generally reflected the improved metabolic status of the calves on the HIGH (P< 0.001). Calves offered a HIGH plane of nutrition were heavier at slaughter (P < 0.001), had larger testes (P < 0.001), larger seminiferous tubule diameter (P < 0.001), more mature spermatogenic cells (P < 0.001) and more Sertoli cells (P < 0.05) in accordance with both morphological and transcriptional data. Overall, testicular gene expression profiles suggested a more mature stage of development in HIGH compared with LOW and were more closely aligned to that of mature bulls. Ghrelin receptor was the only differentially expressed gene between LOW and HIGH calves in either the anterior pituitary (P < 0.05) or arcuate nucleus region of the hypothalamus (P < 0.10) and was upregulated in LOW for both tissues. This study indicates that an enhanced plane of nutrition during early calfhood favourably alters the biochemical regulation of the hypothalamus–anterior pituitary–testicular axis, advancing testicular development and hastening spermatogenesis.

Die Vielseitigkeit des Schlafes

Hintergrund: Die Wirkung von beeinträchtigtem Schlaf auf die Schmerzempfindung, die Regeneration und das Wohlbefinden wird sowohl von medizinischem Personal als auch von Patienten oft zu wenig beachtet.

Ziel: Dieser Artikel zeigt auf, dass verschiedene mit dem Schlaf zusammenhängende Krankheitsbilder in der Physiotherapie behandelt werden können.

Methode: Es werden 3 verschiedene typische Fallbeispiele mit folgenden Diagnosen beschrieben: (1) Kopfschmerzen bei obstruktivem Schlafapnoe-Syndrom, (2) Insomnie und (3) chronisches Schmerzsyndrom und Störung des Schlaf-Wach-Rhythmus. Die Beispiele illustrieren einige Möglichkeiten der physiotherapeutischen Praxis.

Ergebnisse: Bei allen 3 Patienten erzielten physiotherapeutische Maßnahmen gesundheitliche Verbesserungen (erholsamerer Schlaf, Verbesserung der Atmung während des Schlafes, erhöhtes Wohlbefinden, Schmerzreduktion).

Schlussfolgerung: Für einen wirksamen Schlaf und reduzierte Beschwerden (Schmerzen, Fatigue) müssen individuelle Lösungen angeboten werden.

Oral flurbiprofen metabolic ratio assessment using a single-point dried blood spot

We investigated whether a single blood measurement using the minimally invasive technique of a finger prick to draw a blood sample of 5 µl (to yield a dried blood spot (DBS)) is suitable for the assessment of flurbiprofen (FLB) metabolic ratio (MR). Ten healthy volunteers who had been genotyped for CYP2C9 were recruited as subjects. They received FLB alone in session 1 and FLB with fluconazole in session 2. In session 3, the subjects were pretreated for 4 days with rifampicin and received FLB with the last dose of rifampicin on day 5. Plasma and DBS samples were obtained between 0 and 8 h after FLB administration, and urine was collected during the 8 h after administration. The pharmacokinetic profiles of the drugs were comparable in DBS and plasma. FLB's apparent clearance values decreased by 35% in plasma and DBS during session 2 and increased by 75% in plasma and by 30% in DBS during session 3. Good correlations were observed between MRs calculated from urine, plasma, and DBS samples.

Proteome analysis and genome-wide regulatory motif prediction identify novel potentially sex-hormone regulated proteins in rat efferent ducts

The efferent ducts are a series of tubules that conduct sperm from the rete testis to the epididymis. They absorb most fluid and proteins originating from the rete testis during concentration of spermatozoa prior to their entry into the epididymis. Proteome analysis of micro-dissected efferent duct samples from adult rats was combined with genome-wide computational prediction of conserved hormone response elements to identify factors likely regulated by oestrogens and androgens. We identified 165 proteins and found subsets of the promoters controlling their corresponding genes to contain androgen- and oestrogen response elements (ARE/EREs) at similar frequencies. Moreover, EREs were significantly enriched among the loci identified compared with their genome-wide occurrence. The expression and localization of Anxa6, Ckb, Krt19, Park7, Pdzk1 and Tpt1 in the efferent ducts and other related hormone controlled tissues was further validated at the RNA or protein level. This study identifies many novel proteins predicted to play roles in sperm maturation and male fertility and provides significant computational evidence that the efferent ducts express genes transcriptionally controlled by sex hormones.

[Ethyl glucuronide: a biomarker of alcohol consumption]

Excessive alcohol consumption represents a major risk factor for morbidity and mortality. It is therefore indispensable to be able to detect at-risk drinking. Ethyl glucuronide (EtG) is a specific marker of alcohol consumption. The determination of ethyl glucuronide in urine or blood can be used to prove recent driving under the influence of alcohol, even if ethanol is no longer detectable. The commercialization of an EtG specific immunological assay now allows to obtain preliminary results rapidly and easily with satisfying sensitivity. Moreover, the detection of ethyl glucuronide in hair offers the opportunity to evaluate an alcohol consumption over a long period. The EtG concentration in hair is in correlation with the amount of ingested alcohol. Thus, the analysis of ethyl glucuronide can be used to monitor abstinence, to detect alcohol relapse and to identify at-risk drinkers. However, a cut off allowing to detect chronic alcohol abuser reliably still does not exist. Therefore, it is recommended to perform the analysis of ethyl glucuronide in complement to the existing blood markers. A study financed by the Swiss Foundation for Alcohol Research is actually conducted by the West Switzerland University Center of Legal Medicine in order to establish an objective cut-off.

Hair analysis to document a clinical case of TCDD over-exposure

Dioxins and related compounds (furans) are persistent environmental contaminants that cause adverse biological effects. Their influence on humans is still unclear, except for accidental high-dose exposure. Chronic exposure to these compounds seems to be involved in cancer, endocrine disruption and neurobehavioral effects. For several years, a large concern about the potential health risks of dioxins is emerging in Europe and United States. The case of a 50-year-old man victim of an acute over-exposure to tetrachloro dibenzo-p-dioxin (TCDD or Seveso dioxin) is reported here with particular focus on hair investigations. The developed method involved the decontamination of the hair strand using picograde level methylene chloride, the homogenization of hair segments with scissors and their extraction in presence of 13C12-marked dioxin congeners under reflux of toluene using a Soxhlet, 8h at 130 degrees C. After reduction of the toluene fraction to 1 ml and addition of purification marker (37Cl4-2,3,7,8-TCDD), dioxins purification was achieved using three successive columns: silica, alumina/sodium sulfate and carbon/Celite columns. Finally, the toluene eluent was evaporated and the extract injected in the analytical system. After chromatographic separation, detection was achieved in single ion monitoring mode using a high resolution mass spectrometer operating in electron impact ionization mode (40 eV, minimal resolution of 10,000). The analysis of the first hair segment (0-6 cm) revealed the presence of 2,3,7,8-TCDD at 65 fg/mg when the distal one remained negative (LOQ=0.3 fg/mg). All other congeners (n=16) were in the range of those determined in the general population (0.62 and 0.89 fg/mg in the two hair segments, respectively). The extremely low dioxin levels generally found in hair specimens (low fg/mg range) lead us to analyze them using the very sensitive and specific gas chromatography-high resolution mass spectrometry apparatus. From the best of our knowledge, this is the first case of over-exposure to Seveso dioxin through hair analysis reported in the literature.

Principe de la vitrification : cinétiques comparatives

Over the last decade, several methods have been designed to improve the survival rate of vitrificated embryos. Although some teams have succeeded, the main remaining drawback of these methods is that they do not provide a leak proof environment for cryopreserved biological samples. To respond to that demand in respect with the European reglementation, the Cryo Bio System company (CBS) designed the HSV High Security Vitrification Kit (HSV). This system is composed of three distinct parts, a High Security thermal-autogenic sealed clear straw, a capillary with its extremity in form of a gutter, and an introducer that can be mounted on the manipulation rod before introduction into the straw. In this study, we confirmed that the CBS vitrification kit is a suitable method for vitrification in association with a small amount of cryoprotector enriched viscous media such as 25 microM Ficool 400, 750 mM Sucrose, 1% Bovine albumin, 20% Dimethyl Sulfoxide and 20% Ethylene glycol in a Phosphate buffered saline solution. We also evaluated the speed of the temperature decrease during vitrification in comparison with four other commercially available non-aseptic methods and showed the protective role of the CBS system during transfer. These physical data have now been confirmed biologically by P. Vanderzwalmen who obtained easily reproductible good results with human embryo using our method. Today, the HSV represents the unique aseptic alternative device (EC and FDA approved) for embryos, oocytes, and biological samples vitrification.

Human testis in organotypic culture: application for basic or clinical research

BACKGROUND

Over recent decades, recurring efforts have been devoted to developing testicular cell or tissue cultures for basic and clinical research. However, there remains much confusion, particularly concerning the fate of human germ cells in culture.

OBJECTIVE

To reassess the status of human testicular cell types as well as the ability of germ cells to divide and differentiate in organotypic culture.

METHODS

Human testicular fragments were maintained for 2 weeks in culture. The viability and functionality of testicular cells were assessed using light and electronic microscopy, apoptotic cell labelling, 5-bromo-2'-deoxyuridine (BrdU) incorporation, immunohistochemistry and quantitative PCR against specific cell markers.

RESULTS

A gradual loss of meiotic and post-meiotic germ cells occurred throughout the culture period, irrespective of the presence of gonadotrophins. However, all germ cell types remained traceable for up to 16 days, some still dividing and differentiating at a rate compatible with the in vivo situation. Good maintenance of the general architecture of the explants associated with clearly quantifiable levels of several somatic cell markers was observed.

CONCLUSION

Although this culture model is clearly unsuitable for preparing germ cells for therapeutic purposes, it does represent a most valuable tool for testing the effects of biological and chemical agents on testicular tissue.

Transferrin overexpression alters testicular function in aged mice

Many studies have shown a correlation between transferrin (Tf) concentration and sperm yield in several mammalian species. We have used transgenic mice expressing human Tf (hTf) to investigate if overexpression of Tf increases the efficiency of mouse spermatogenesis. We demonstrated that a 36% increase of Tf does not ameliorate the efficiency of mouse spermatogenesis but on the contrary resulted in a 36% decrease of testis sperm reserves. Tf overexpression had no effect on testicular determination and development, however testicular function of these transgenic mice was affected in an age-dependent manner. At 16 months of age, testicular and epididymal weights were significantly reduced. While spermatogenesis was qualitatively normal, testicular functions were perturbed. In fact, testosterone rate after human chorionic gonadotropin (hCG) stimulation was lower in Tf overexpressing mice. Intratesticular concentration of estradiol-17beta was increased and fluid accumulation after ligation of rete testis was more abundant in these transgenic mice. Surprisingly, we found that endogenous Tf levels were also increased in Tf overexpressing mice and we demonstrated for the first time that Tf may serve to upregulate its own expression in testis. Collectively, our data show that Tf overexpression has negative effects on testicular function and that Tf levels require strict regulation in the testis.

Climbing Fibre Responses in Olivo-cerebellar Slice Cultures. II. Dynamics of Cytosolic Calcium in Purkinje Cells

The generation of climbing fibre responses in cerebellar Purkinje cells has been analysed in co-cultured slices of rat cerebellum and inferior olive. Complex spikes were evoked in Purkinje cells by climbing fibre activation or by intrasomatic injection of depolarizing current pulses. Microfluorometric measurements of cytosolic free calcium ([Ca2+]i) by means of intracellularly injected fura-2 combined with intracellular recordings revealed that both types of complex spikes were accompanied by a transient rise in [Ca2+]i, which was most prominent at dendritic locations. Synaptically induced Ca2+ transients were completely and reversibly abolished by 6-cyano-7-nitroquinoxaline-2-3-dione (CNQX, 5 microM), an antagonist of the ionotropic action mediated by non-N-methyl-d-aspartate excitatory amino acid receptors. Ca2+ transients evoked by injections of depolarizing current pulses were not affected by CNQX. These observations indicate that Ca2+ transients induced by climbing fibre activity are generated by voltage-gated Ca2+ channels, which are activated by a CNQX-sensitive synaptic depolarization.

Responses to Metabotropic Glutamate Receptor Activation in Cerebellar Purkinje Cells: Induction of an Inward Current

The responses to activation of metabotropic glutamate receptors (mGluRs) of Purkinje cells in rat cerebellar slice cultures were investigated using intracellular recordings in single-electrode voltage-clamp mode combined with microfluorometric measurements of cytosolic free calcium using fura-2. Purkinje cells were perfused with saline containing 0.5 microM tetrodotoxin and 10 microM bicuculline and voltage-clamped at -60 mV. Bath-applied trans-(+/-)-1-amino-1,3-cyclopentanedicarboxylic acid (t-ACPD, 50 - 100 microM), a selective agonist of mGluRs, induced a transient inward current that was followed by an outward current. The response induced by t-ACPD was not affected by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, up to 40 microM). In contrast, inward currents caused by (RS)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA, 1 - 2 microM) were completely abolished, while inward currents caused by quisqualate (0.25 microM) were only partially depressed by CNQX (5 - 40 microM). The inward current induced by t-ACPD was unaffected by external Ba2+ (1 mM), tetraethylammonium (10 mM) and Cs+ (1 mM), and was associated with an increase in apparent input conductance of the cell membrane. The extrapolated reversal potential of inward currents induced by t-ACPD was +18 mV while Cl- currents induced by muscimol reversed at -66 mV. Inward currents induced by t-ACPD, but not those induced by AMPA, were associated with a rise in cytosolic Ca2+ concentration and suppressed by intracellular injection of a calcium chelator. Replacement of external Na+ by choline or Li+ depressed the inward current and resulted in a slower decay of the Ca2+ signal.

Determination of benzodiazepines in human hair by on-line high-performance liquid chromatography using a restricted access extraction column

A method is described for the identification of five frequently prescribed benzodiazepines (BZD) (clonazepam, diazepam, flunitrazepam, midazolam and oxazepam) in human hair samples by reversed phase HPLC, following on-line simple enrichment and clean-up on a restricted access extraction column. 50mg of powdered hair were incubated (2h at 45 degrees C) after sonication (1h) in 1 ml of the following solution (methanol:ammonia, 97.5/2.5, v/v). The aliquot was centrifuged and the methanolic phase transferred to a conical tube and evaporated under a gentle stream of nitrogen. The residue was reconstituted by adding 100 microl of a mixture of phosphate buffer (20mM, pH=2.2) and acetonitrile (94/6, v/v). A total of 80 microl were injected into the system with the column switching technique. The pre-column or clean-up column was washed with phosphate buffer pH=7.2. The drugs retained on the pre-column were then eluted in the back-flush mode and separated on a C(8) semi micro column, Lichrospher select B, 125 mm x 3 mm. The BZD were determined by a photodiode-array detector at 254 nm, using reference data (retention time and UV spectra) stored in a personal library. The method showed excellent linearity between 0.5 and 20 ng/mg of hair for clonazepam, flunitrazepam and midazolam and between 0.5 and 100 ng/mg of hair for diazepam and oxazepam. Finally, the present method has been applied to a number of forensic cases in our laboratory.

Live human germ cells in the context of their spermatogenic stages

BACKGROUND

Various types of live, dispersed, human testicular cells in vitro were previously compared with the morphologic characteristics of human spermatogenic germ cells in situ within seminiferous tubules. The current study extends those observations by placing live human germ cells in the context of their developmental steps and stages of the spermatogenic cycle.

METHODS

Live human testicular tissue was obtained from an organ-donating, brain-dead person. A cell suspension was obtained by enzymatic digestion, and dispersed cells were observed live with Nomarski optics. Testes from 10 men were obtained at autopsy within ten hours of death, fixed in glutaraldehyde, further fixed in osmium, embedded in Epon, sectioned at 20 microm, and observed unstained by Nomarski optics.

RESULTS

In both live and fixed preparations, Sertoli cells have oval to pear-shaped nuclei with indented nuclear envelopes and large nucleoli, which makes their appearance distinctly different from germ cells. For germ cells, size, shape, and chromatic pattern of nuclei, the presence of meiotic metaphase figures, acrosomic vesicles/structures, tails, and/or mitochondria in the middle piece are characteristically seen in live dispersed cells and those in the fixed seminiferous tubules. These lead to identification of live germ cells in man and placement of each in the context of their developmental steps of spermatogenesis at corresponding stages of the spermatogenic cycle.

CONCLUSIONS

This comparative approach allows verification of the identity of individual germ cells seen in vitro and provides a checklist of distinguishing characteristics of live human germ cells to be used in clinical procedures or by scientists interested in studying live cells at known steps in spermatogenic development characteristic of germ cells in specific stages of the spermatogenic cycle.

High-performance liquid chromatography determination of flunitrazepam and its metabolites in plasma by use of column-switching technique: comparison of two extraction columns

A study, using on-line column-switching high-performance liquid chromatography, evaluated two different extraction columns for the determination of flunitrazepam and its major metabolites: 7-aminoflunitrazepam, 7-acetamidoflunitrazepam and desmethylflunitrazepam. The procedure was based on the enrichment of benzodiazepines on the extraction column, followed by transfer of the compounds to the analytical column. The two extraction columns were compared: the first column was a BioTrap 500 MS (hydrophobic polymer), 20x4 mm I.D., and the second was a LiChrospher RP-18 ADS, 25x4 mm I.D. The analytical column used was a LiChrospher select B RP-8, 125x3 mm I.D. with 5 microm particle size. The extraction conditions for the two pre-concentration columns, such as extraction temperature, buffer concentration, buffer pH, acetonitrile percentage and flow-rate, were studied for the extraction from plasma of flunitrazepam and its metabolites mentioned above. The mobile phase of the analytical column was isocratic and composed of acetonitrile-20 mM phosphate buffer at pH 2.1 (35:65, v/v) and at a flow-rate of 0.3 ml/min.

Methadone and EDDP in hair from human subjects following a maintenance program: results of a pilot study

A specific method has been developed for the quantitative determination of methadone (MTD) and its major metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), in hair.An amount of 50mg hair samples were incubated in 0.01M HCl overnight at 60 degrees C and deuterated internal standards of MTD and EDDP were added before extraction. Hydrolyzed solutions were extracted by automated solid-phase extraction procedure and analyzed on a gas chromatography (GC) coupled to a ion trap mass spectrometer (MS). Positive chemical ionization was used with acetonitrile as liquid reagent. The different validation parameters, linearity, repeatability, recovery and detection limits are presented. A relative standard deviation (R.S.D.) of 12 and 11% was obtained for the repeatability of MTD and EDDP, respectively. The limits of quantification (LOQ) was 0.05ng/mg for MTD and 0.2ng/mg for EDDP.A number of 26 hair samples from human subjects following a long-term MTD therapy were analyzed by this method. Blood samples of these subjects were analyzed with a routine method using a liquid-liquid extraction and GC/nitrogen phosphorus detector (NPD). MTD was quantified in blood and hair samples and EDDP found in 50% of the hair sample.A comparison was made between the concentrations found in blood or in hair and the dose administrated. This study could demonstrate that there is no relation between the administrated dose and MTD or EDDP concentrations in hair.

Semiautomated high-performance liquid chromatographic method for the determination of benzodiazepines in whole blood

A semiautomated method for the determination of five frequently prescribed benzodiazepines (BZD) (clonazepam, diazepam, flunitrazepam, midazolam, and oxazepam) in whole blood samples by reversed-phase high-performance liquid chromatography following simple online enrichment and clean-up on a short precolumn is described. After precipitation of protein and red cells with a mixture of organic solvents (methanol/acetonitrile, 50:50), the aliquot is centrifuged and the organic upper phase evaporated under a gentle stream of nitrogen. The residue is reconstituted by adding 500 microL of a mixture of phosphate buffer (20mM, pH 2.2) and acetonitrile (70:30, v/v). The sample is then directly introduced into the column-switching column. The precolumn is first washed with phosphate buffer at pH 7.2. Compounds retained on the precolumn are then eluted in the back-flush mode and separated on a C8 semi-microcolumn (Lichrospher select B, 125 x 3 mm). The BZD studied are determined by a diode-array detector at 254 nm. The method shows excellent linearity between 25 and 1,000 ng/mL for clonazepam, flunitrazepam, and midazolam and between 25 and 5,000 ng/mL for diazepam and oxazepam. The recoveries are around 80% for clonazepam and oxazepam and around 90% for the three others. Coefficients of variation for between-day and within-day assays are < 15% for low concentrations close to the limit of quantitation and < 5% for high concentrations.

Acetylcodeine as a marker of illicit heroin in human hair: method validation and results of a pilot study

Acetylcodeine (AC), which is an impurity of illicit heroin synthesis, was suggested as a marker of heroin abuse. A procedure for simultaneous quantitation of 6-monoacetylmorphine (6-MAM), which is the major metabolite of heroin, morphine, codeine, and AC in hair was developed. Fifty-milligram hair samples were incubated in 0.01 M HCl overnight at 60 degrees C. The resulting hydrolyzed solutions were extracted by an automated solid-phase extraction procedure and drugs were analyzed by gas chromatography-mass spectrometry in selected ion monitoring mode (SIM). This required prior derivatization with propionic anhydride. Different validation parameters, such as linearity, intra-assay accuracy, extraction recoveries, and limit of quantitation, were described. Seventy-three hair samples from heroin abusers and 43 hair samples from subjects who had completed a heroin-maintenance program were analyzed. AC was detected in 92% of the first sample group and in only 12% of the second sample group. In the two groups, about 98% of AC-positive samples were found. These results prove that AC can be considered as a suitable marker of illicit heroin use, along with 6-MAM detection.

Detection of acetylcodeine in urine as an indicator of illicit heroin use: method validation and results of a pilot study

BACKGROUND

Acetylcodeine (AC), an impurity of illicit heroin synthesis, has been suggested as an interesting biomarker of illicit heroin use.

METHODS

Procedures were developed for quantification of (a) morphine, 6-monoacetylmorphine (6-AM), and codeine in urine and (b) diacetylmorphine and AC in urine. Solid-phase extraction of the analytes was performed, and the extracted analytes were analyzed by selected-ion monitoring with gas chromatography-mass spectrometry. This procedure required prior derivatization with propionic anhydride.

RESULTS

Different validation parameters were determined, such as linearity, reproducibility, extraction recoveries, and cutoffs. Seventy-one urine specimens of illicit heroin abusers and 44 urine specimens of subjects in a heroin maintenance program were analyzed. AC was detected in 85.9% of the samples of the first group but not in any of the samples from subjects taking medical heroin. In the two groups, there were 94.4% and 84.1% 6-AM positive urine specimens, respectively. Detection times were determined for AC and codeine by parallel administration of heroin containing various percentages of AC to four voluntary patients in a heroin maintenance program. The measured detection times were 8 and 23 h for AC and codeine, respectively.

CONCLUSIONS

These results indicate that, together with detection of 6-AM in urine, AC is a suitable marker of illicit heroin use.

Stability of benzodiazepines in whole blood samples stored at varying temperatures

Study has been undertaken to determine the stability of four benzodiazepines: clonazepam, midazolam, flunitrazepam and oxazepam in whole blood samples. Spiked blood was stored at four different temperatures (room temperature, 4 degrees C, -20 degrees C and -80 degrees C) and analysed at selected times during one year. Determination was performed on the first, third and seventh day during the first week, then once a week for three weeks, once every two weeks for four weeks, then once a month for 4 months and finally, once every 2 months. Extraction was performed using liquid-liquid extraction with 1-chlorobutane, while quantification was carried out using high performance liquid chromatography equipped with a photodiode-array ultraviolet detector. At room temperature, the concentration of all benzodiazepines decreased over one year to 100 and 70% for low and high concentrations, respectively. At 4 degrees C, the decrease was between 90 and 100% for low concentrations and between 50 and 80% for high concentrations. At -20 degrees C, the measured decrease was between 10 and 20% for high and low concentrations, respectively. At -80 degrees C, the measured loss was not significant at high concentration except for midazolam. However, at low concentration the determined decrease was between 5 and 12%. The data collected suggests that quantitative results concerning long-term stored samples should be interpreted with caution in forensic cases. Further investigations concerning the stability of drugs in whole blood or other biological samples, additional methods of identification and determination as well as the establishment of optimal storage conditions should be undertaken in forensic cases.

The whole meiotic process can occur in vitro in untransformed rat spermatogenic cells

The aim of the present study was to assess whether the whole meiotic process of spermatogenic cells is able to take place in vitro. Fragments of seminiferous tubules from 20- to 22- or 28-day-old rats were seeded in medium containing 0.2% fetal calf serum in bicameral chambers and then cultured for 4 weeks in a chemically defined medium. The differentiation of meiotic germinal cells was followed by four criteria: (i) ultramicroscopic examination of the different types of germ cells present in the cell layer throughout the culture period; (ii) determination of the changes in DNA content per nucleus of the cell population seeded with time in culture; (iii) assessment of the ability of germinal cells to transcribe genes expressed after completion of meiosis; and (iv) monitoring the fate of BrdU-labeled leptotene spermatocytes. The ultrastructural study showed that the overall organization of the cells in the culture well recalls that of the seminiferous epithelium throughout the culture period. Moreover the identification of young round spermatids 21 days after seeding suggested that these spermatids had been formed very recently in culture. Determination of DNA content per nucleus showed that a 1C cell population could be observed after several days of cultures reaching 6 to 10% of total cells. An exponential-like increase in the amounts of the mRNAs encoding for TP1 or TP2 occurred from the time when 1C cells appeared in the culture until the end of the experiment. Finally, BrdU-labeled leptotene spermatocytes differentiated into pachytene spermatocytes and then into secondary spermatocytes, and BdrU-labeled round spermatids were observed from Day 21 of culture onward. Taken together these results indicate that the whole meiotic process from leptotene spermatocyte to round spermatid can indeed occur in vitro under the present culture conditions.

Simultaneous determination of benzodiazepines in whole blood or serum by HPLC/DAD with a semi-micro column

A simple and sensitive high performance liquid chromatographic (HPLC) method using a semi-micro column, C8 reversed-phase column (3 mm i.d.) and a low flow rate 0.3 ml/min was developed and validated for the determination of five frequently prescribed benzodiazepines: clonazepam, diazepam, flunitrazepam, midazolam and oxazepam. Quantification was performed at 220 nm with methylclonazepam as internal standard. The method involved a simple extraction from alkalinized blood (1 ml) into 1-chlorobutane and provided excellent sensitivity, recovery, accuracy and reproducibility for benzodiazepines in therapeutic or toxic concentrations.

High-performance liquid chromatographic method for the determination of benzodiazepines in plasma or serum using the column-switching technique

A column-switching high-performance liquid chromatographic method for the simultaneous determination of five frequently prescribed benzodiazepines: clonazepam, diazepam, flunitrazepam, midazolam and oxazepam was developed. A 50-microl plasma sample was directly injected into a BioTrap 500 MS (hydrophobic polymer) column. After a washing step with a mixture of phosphate buffer and acetonitrile, the retained benzodiazepines were back-flushed into a reversed-phase (LiChrospher Select B C8) column with a mobile phase of acetonitrile-phosphate buffer. The method showed excellent linearity from 50 to 1000 ng/ml for clonazepam, flunitrazepam and midazolam and from 50 to 5000 ng/ml for diazepam and oxazepam. The recoveries were around 98% for all the benzodiazepines studied. The relative standard deviation for between-and within-day assay was <20% for low concentrations close to the values of the limit of quantification and <4% for high concentrations. The procedure described is relatively simple and rapid because no off-line manipulation of the sample is required: the total analysis time is approximately 30 min.

Analysis of drugs of abuse in hair by automated solid-phase extraction, GC/EI/MS and GC ion trap/CI/MS

In our laboratory, analysis of human hair for the detection of drugs of abuse was first performed in 1995. Initially, requests for hair analysis were few, and it is only since 1997 that these analyses have become routine. As demand grew, we developed an automatic solid-phase extraction method; the use of a robot ASPEC allowed us to drop certain fastidious manipulations, and to treat a large number of samples at a time. This method is described, along with analysis by gas-chromatography-mass spectrometry (GC/MS) in selected ion monitoring mode (SIM), for the following drugs: codeine, 6-monoacetylmorphine (6-MAM), morphine, cocaine, methadone, ecstasy (MDMA) and Eve (MDE). This requires prior derivatization with propionic anhydride. The different validation parameters, linearity, repeatability, recovery and detection limits are described, as well as the application of this method to some real cases. Analysis of these cases is also performed by an ion trap GC/MS in chemical ionization mode (GC/IT/CI/MS) in order to demonstrate the usefulness of this technique as a complement to routine analysis. Analysis by GC/IT/CI/MS indeed avoids the risk of false-positive results by the identification of metabolites.

Chromatographic procedures for determination of cannabinoids in biological samples, with special attention to blood and alternative matrices like hair, saliva, sweat and meconium

This paper reviews chromatographic procedures for determination of cannabinoids in biological samples. Special attention was focused on blood and alternative matrices like hair, saliva, sweat and meconium. Papers published from 1998 to the early beginning of 1999 were taken into consideration. Gas chromatographic and liquid chromatographic procedures with different detectors (e.g. mass spectrometer or diode array) were considered. Basic information about the biosample assayed. sample preparation, work-up, gas chromatography column or liquid chromatography column and mobile phase, detection mode, reference and validation data are summarized in tables.

Determination of atropine in biological fluids by micellar electrokinetic capillary chromatography in the presence of strychnine and tetracaine

The identification and quantitation of atropine, in whole blood and gastric contents in the presence of strychnine and tetracaine is described. This method uses liquid-liquid extraction and micellar electrokinetic chromatography (MECC). Separations are made using a 50 cm long capillary and a borate/phosphate buffer at pH 9.2 with 50 mM sodium dodecyl sulfate (SDS). Linearity was established for the three compounds between 1.0 and 100 microg/mL, using scopolamine as internal standard. The limit of detection for atropine was estimated at 0.06 microg/mL and the limit of quantitation at 0.2 microg/mL. The run time is less than 30 min. Alternate parameters are proposed to reduce the run time to under 10 min. The method was applied to a forensic post-mortem case.

Meiotic differentiation of germinal cells in three-week cultures of whole cell population from rat seminiferous tubules

The aim of the present study was to set up a culture system allowing most of the meiotic phase of rat spermatogenesis to occur in vitro. For that purpose, the differentiation of spermatogenic cells was monitored by three criteria: 1) examination of expression of genes specifically expressed at a high level in pachytene spermatocytes (the phosphoprotein p19 [p19] and the testis-specific histone TH2B) or in round spermatids (transition protein 1 [TP1] and transition protein 2 [TP2]) by reverse transcription-polymerase chain reaction (RT-PCR); 2) ploidy analysis; and 3) cytological and immunocytochemical study of the germ cells. In the first trial, we determined the changes in the ratios of p19:TP1 and TH2B:TP2 mRNA-related PCR products in the whole testis of rats between 18 and 60 days postpartum and related those results to the sequential appearance of the various types of spermatogenic cells during that period. In the second trial, our aim was to reproduce, in a culture system using seminiferous tubules from 23- to 25-day-old rats, the changes observed in vivo. The p19:TP1 and TH2B:TP2 ratios decreased dramatically in testicular extracts of rats between 32 and 40 days postpartum, i.e., at the time period during which round spermatids become more and more numerous in the testis. When seminiferous tubules were seeded in bicameral chambers, cell viability remained close to 70% of total cells throughout the 3-wk culture period. Both p19:TP1 and TH2B:TP2 ratios decreased during the first week of culture. This was attributable to a decrease in the levels of p19 and TH2B mRNAs and also to an enhancement in the relative amounts of TP1 and TP2. These changes were correlated with the appearance of a 1C cell population in the culture. Histological examination of the culture demonstrated that under the conditions of the present study, 5-bromo-2'-deoxyuridine-labeled pachytene spermatocytes of stages IV-VI were able to differentiate into secondary spermatocytes, then into round spermatids.

Analysis of methaqualone in biological matrices by micellar electrokinetic capillary chromatography. Comparison with gas chromatography-mass spectrometry

The analysis of methaqualone (MTQ) in biological matrices by capillary electrophoresis (CE) is described. This methods uses liquid-liquid extraction and micellar electrokinetic capillary chromatography (MECC), an operation mode of CE. Separations are made using a 25 cm long capillary and a borate/phosphate buffer at pH 8.2. Using gas chromatography with mass spectrometry detection (GC-MS) as reference method, MTQ has been analyzed in urine, blood, gastric content and hair. For hair analysis, supercritical fluid extraction was compared with liquid-liquid extraction. Linearity was established in urine and blood between 0.25 and 10.0 micrograms/ml. MTQ recovery from blood was estimated at 60%. The limit of detection of this method in urine is about 0.10 microgram/ml. Drawbacks and advantages of MECC over GC-MS are discussed.

[In vitro murine spermatogenesis: cytologic study of the meiosis stage]

Spermatogenesis is a complex process of cellular multiplication and differentiation, the regulation of which is only partially understood. This may be due; 1) to the redundancy of the mechanisms of local regulation; 2) to the ubiquitous character of those growth factors and cytokines present in the testis; 3) to the lack of long term culture systems allowing male germ cell development. We describe herein two culture systems associating Sertoli cells and germ cell in which part of the meiotic step can occur in vitro. In the first system, pachytene spermatocytes prepared by centrifugal elutriation are cultured on a layer of Sertoli cells. In the second system small fragments of seminiferous tubules are seeded in bicameral chambers. The cytological and immunocytochemical studies presented show that pachytene spermatocytes of stages IV-VI differentiate into spermatids of steps 1 to 5.

Testing human hair for flunitrazepam and 7-amino-flunitrazepam by GC/MS-NCI

To validate information on flunitrazepam use, we investigated human hair for flunitrazepam and its major metabolite 7-amino-flunitrazepam by gas chromatography coupled to mass spectrometry in negative chemical ionization mode of detection. Samples were twice decontaminated with methylene chloride, pulverized in a ball mill and 50 mg of powdered hair were incubated in Soerensen buffer (pH 7.6) in the presence of diazepam-d5 used as internal standard. After liquid-liquid extraction of the incubation medium with diethylether-chloroform (80:20, by vol.), the organic phase was evaporated and the dry extract was derivatizated with heptafluorobutyric anhydride. Benzodiazepines were separated on a 30 m capillary column and detected using single ion monitoring. Among 40 hair samples tested (obtained from drug addicts deceased by heroin overdose), 14 were positive for both flunitrazepam and 7-amino-flunitrazepam and 12 for 7-amino-flunitrazepam only. Concentrations ranged from 31 to 129 pg/mg (mean: 60 pg/mg) and from 3 to 161 pg/mg (mean: 46 pg/mg) for flunitrazepam (14 cases) and 7-amino-flunitrazepam (26 cases), respectively. This first report described the detection of flunitrazepam and 7-amino-flunitrazepam in hair of chronic abusers. Due to the low concentrations observed, negative chemical ionization appears to be the alternative to test flunitrazepam and other benzodiazepines in hair.

[Biomechanical comparative study of three types of osteosynthesis in the treatment of supra and intercondylar fractures of the humerus in adults]

PURPOSE OF THE STUDY

Supra and intercondylar fractures are the most common fractures of the distal end of the humerus in adult. An osteosynthesis consisting of a plate is the treatment of choice. But location and type of plate always remain open for debate. The authors present the results of an in vitro biomechanical study, which compared the stiffness of three types of osteosynthesis commonly used in these fractures.

MATERIAL AND METHODS

The devices were on one hand the premolded lateral plate of Lecestre and Dupont (Howmedica) used alone or in conjunction with a medial 1/3 tubular plate of the AO group, and on the other hand a posterior plate, of which we are developing a new model, the Lambda plate (Protek) "Y"-shaped, monoblock, flat and molded on the humerus during operation. The study compared these different methods of fixation on fresh human humeri. In a first part, the posterior plate was compared to the single lateral one; in a second part, the posterior plate was compared to the coupled lateral and medial plates. The three plates were made of identical material. Both studies used eight pairs of bones with supra and intercondylar fractures realized by sawing. Each bone of a pair was fixed with one of the two types of device. Each humerus underwent different loading forces; sagittal bending (anterior and posterior) and torsion. The displacements were recorded using a calibrated measuring device coupled to two displacement sensors. The stiffness was calculated on force/displacement curves.

RESULTS

In anterior bending, the Lambda posterior fixation was significantly stiffer than the single lateral one (p < 0.05) (239 +/- 109 versus 129 +/- 65 N/mm), and was not significantly different of the bilateral fixation (229 +/- 93 versus 224 +/- 108 N/mm). In posterior bending, the mean stiffness of the Lambda fixation was not significantly different to that of the lateral fixation (91 +/- 27 versus 91 +/- 52 N/mm), and less than that of the bilateral one (130 +/- 39 versus 170 +/- 70 N/mm), but not significantly. In torsion the mean stiffness of the Lambda fixation was superior to that of the lateral one (146.75 +/- 50.66 versus 119.75 +/- 58.8 Nm/rad), and bilateral one (233.31 +/- 107.47 versus 212.31 +/- 113.55 Nm/rad), but again not significantly.

DISCUSSION

The ideal osteosynthesis for the fractures of the humeral distal doesn't exist, because the bone undergoes antero-posterior and posteroanterior cyclical forces during elbow flexion. Therefore the best device should be placed on both sides of the bone, but anatomical reasons make this location impossible. According to our study, we think the "less worst" device is the posterior one using the Lambda plate. Its symmetrical design allows a best loading distribution on the two columns. Its thickness compensates for its posterior location and the short interval between two holes allows to put many screws (4 to 6) into the epiphysis. All supra and intercondylar fractures, comminuted or not, can be treated with this material. The single lateral device isn't still enough. Its stiffness mainly depends on the orientation of the oblique screw in the medial column. But the design of this column doesn't always allow for an optimal location of the screw, which is the reason of several failures. The bilateral device gives a stiffness, comparable to the posterior one, but doesn't allow as many screws as the Lambda plate in the epiphysis. Therefore, it can't be used in very distal fractures.

CONCLUSION

In spite of the progress of the material and the accuracy of the indications, the treatment of supra and intercondylar fractures of the distal end of the humerus is always a difficult problem. The devices have to be as stable as possible to allow an early motion. The best one should be placed on both sides of the distal humerus, because of the sagittal cyclic forces it undergoes, but this location is anatomically impossible. Our study concludes that the device using the Lambda plate i

Analytical procedures for determination of opiates in hair: a review

This article reviews the analysis of opiates in hair. Hair matrix pretreatment, hydrolysis, extraction and detection procedures are presented amongst a study of over 70 bibliographic data. In addition, a new method for the extraction of opiates from hair, in which a powdered sample of hair is extracted directly by subcritical fluid, is presented.

Voltage-imaging and simulation of effects of voltage- and agonist-activated conductances on soma-dendritic voltage coupling in cerebellar Purkinje cells

We investigated the spread of membrane voltage changes from the soma into the dendrites of cerebellar Purkinje cells by using voltage-imaging techniques in combination with intracellular recordings and by performing computer simulations using a detailed compartmental model of a cerebellar Purkinje cell. Fluorescence signals from single Purkinje cells in cerebellar cultures stained with the styryl dye di-4-ANEPPS were detected with a 10 x 10 photodiode array and a charge coupled device (CCD). Fluorescence intensity decreased and increased with membrane depolarization and hyperpolarization, respectively. The relation between fractional fluorescence change (delta F/F) and membrane potential could be described by a linear function with a slope of up to -3%/100 mV. Hyperpolarizing and depolarizing voltage jumps applied to Purkinje cells voltage-clamped with an intrasomatic recording electrode induced dendritic dye signals, demonstrating that these voltage transients invaded the dendrites. Dye signals induced by depolarizing somatic voltage jumps were weaker in the dendrites, when compared with those induced by hyperpolarizing voltage jumps. Dendritic responses to hyperpolarizing voltage steps applied at the soma were attenuated when membrane conductance was increased by muscimol, an agonist for GABA(A) receptors. Corresponding experimental protocols were applied to a previously developed detailed compartmental model of a Purkinje cell. In the model, as in the electrophysiological recordings, voltage attenuation from soma to dendrites increased under conditions where membrane conductance is increased by depolarization or by activation of GABA(A) receptors, respectively. We discuss how these results affect voltage clamp studies of synaptic currents and synaptic integration in Purkinje cells.

Subcritical fluid extraction of opiates in hair of drug addicts

Hair analysis is a useful complement to blood and urine analysis in forensic science, but current procedures are tedious and time consuming. Owing to the difficulty of having a sufficient amount of hair in order to perform the optimization of the extraction method, standard hair was made and the procedure is described. The spiking method is reproducible and linearity can be obtained. Subcritical fluid extraction of opiates from standard and drug addicts' hair was optimized (extraction phase composition, extraction time, etc.) and compared with other extraction techniques (basic and acid hydrolysis, organic solvent and enzymatic digestion) followed by solid-phase extraction. Recovery, coefficient of variation, linearity, detection limits and quantification limits for the subcritical fluid extraction of opiates in hair are described.

[Presence of psychotropic drugs in the blood of drivers responsible for car accidents, and who consumed alcohol at the same time]

The presence of psychotropic drugs was determined in 383 blood samples of drivers being responsible for car accidents, having taken alcohol as well. Benzodiazepines were detected in 52 cases and cannabinoids in 31 cases. The characterisation of these positive cases showed a majority of classic benzodiazepines (diazepam, nordiazepam, and bromazepam). Even if the specific role of these two families of psychotropic drugs cannot be deduced from this study, the results should make drivers more aware of the dangers of the simultaneous consumption of alcohol and psychotropes.

Hair analysis: its importance for the diagnosis of poisoning associated with opiate addiction

In forensic toxicology, hair analysis for determining intoxication by inorganic substances has received much attention. Organic substances, on the other hand, are also found in hair and therefore hair should be regarded as an important source for evaluation of drug use. This paper examines the advantages and limitations of hair analysis in the measurement of opiates by using hair taken from some actual drug users in Switzerland.