Pharmacokinetic study of midazolam and α-hydroxymidazolam in guinea pig blood and hair roots after a single dose of midazolam.

The appearance of midazolam (M) and its metabolites into the hair root following a single administration was examined by following the time course of M and α-hydroxymidazolam (αHM) in hair roots and blood from guinea pigs. The back hair of guinea pigs was shaved before drug administration and before each sampling, and hair roots (3-5 mm) were plucked at 5, 15, and 30 min, 1, 2, 4, 6, 10, 24, 48, 72, 96, 120, 144 h, and 7, 14, 21, and 28 days. The kinetic parameters of M and αHM in guinea pig blood and hair roots were determined for three doses (5, 10, and 25 mg/kg). Comparisons of drug time course between hair roots and blood indicated an association between drug concentrations in the hair root and the blood. M and αHM entered the hair root within 5 min after a single exposure. The detection windows were also longer for the hair root than for the blood. Consequently, the hair root can be a valuable specimen in acute poisonings or drug-facilitated crime (DFC) cases, if other matrices are unavailable, or if blood and urine results are negative. Hair shafts (with hair roots) were plucked at 28 days and segmented. The concentrations of M and αHM were lower in the hair shafts than in the hair roots. The concentrations of the metabolite αHM in hair shafts were barely detectable. The concentrations of M and αHM in the hair root showed a moderate correlation with dose. Comparison of drug levels in hair roots between the washed group and the unwashed group indicated a generally stable percentage between the washed and unwashed groups of 40-60 % during the entire time course. This indicates that drugs are likely to be immobilized in the hair root at the beginning of the incorporation process.

Whole-genome resequencing using genomic DNA extracted from horsehair roots for gene-doping control in horse sports.

Gene doping is prohibited in horseracing and equestrian sports. In previous studies, we developed non-targeted transgene and genome editing detection methods based on whole genome resequencing (WGR) using genomic DNA extracted from whole blood. In this study, we aimed to develop a WGR method using DNA extracts from hair roots. Hair roots are a preferred substrate because their collection is less invasive than blood collection. Hair is also easier to store for long periods of time. Although almost all genomic DNA extracted from hair root samples stored for years at room temperature was degraded, the quality of genomic DNA from samples stored for years at refrigerated temperatures (4-8°C) was maintained. High-molecular-weight genomic DNA was isolated from hair roots using a magnetic silica beads method of extraction, enabling WGR from horsehair root extracts. Nucleotide sequencing results and numbers of single-nucleotide polymorphisms and insertions/deletions concurred with those previously reported for WGR of DNA extracted from whole blood. Therefore, we consider that storing hair samples at refrigerated temperatures prevents degradation of DNA, allowing the detection of gene doping in these samples based on WGR. It is likely this finding will also have a deterrent effect, as it is now possible to test horses with archived samples even if they or their parents are deceased. To our knowledge, this is the first report employing WGR on horsehair roots stored for a long term.

A quantitative method for selecting a hair for nulear DNA analysis.

This study evaluated a quantitative method to predict the success of nuclear DNA (nuDNA) typing for head hair roots, using the minor-groove DNA binding dye, 4', 6-diamidino-2-phenylindole (DAPI). The procedure was successful in staining nuclear material in hair roots, regardless of soft tissue presence or growth phase. We found that the dye can even reveal an abundance of visible nuclei in hairs that were previously assumed to be unsuitable for nuDNA analysis (e.g., telogen hairs). The value of DAPI staining is particularly evident when considering the STR typing results for telogen hairs. Here, telogen hairs with greater than 100 visible nuclei frequently produced full or high-partial STR profiles, while telogen hairs with fewer than 100 visible nuclei rarely resulted in >20 % STR allele recovery. In addition, our findings indicated no interference by DAPI in the forensic examination of hair evidence, including preparation of hairs on microscopic slides, microscopic examination, DNA extraction, quantitative PCR, and short tandem repeat (STR) typing. Furthermore, the method remained steadfast for hairs washed by sonication as well as hairs retrieved from Permount™ mounting medium. When validated, this simple, quick, and quantitative screening method can be used in casework to select a hair for nuDNA analysis, especially for hairs that were previously sent directly for mitochondrial (mt) DNA analysis based on the lack of adhering soft tissue, regardless of growth phase. Conversely, nuDNA degradation may exist in hairs which exhibit microscopic characteristics typically associated with a potential to generate successful nuclear DNA profile including stretched roots with attached root sheath. DAPI staining of hairs gives forensic examiners the ability to have more information, other than growth phase, when selecting a hair or hairs for possible nuDNA analysis.

Characteristics of quetiapine and 7-hydroxyquetiapine in hair roots and blood after a single dose of quetiapine.

This study investigated the kinetics of quetiapine and its metabolite 7-hydroxyquetiapine in guinea pig blood and hair roots during the whole time course of absorption and elimination after intragastric administration of three dosages (25 mg/kg, 50 mg/kg, 100 mg/kg). The mean maximum concentration (Cmax) values of quetiapine in the blood of the low-, medium- and high-dose groups were 334.4, 849.0, and 2751.1 ng/mL, respectively, and those of 7-hydroxyquetiapine were 75.6, 175.5, and 173.7 ng/mL, respectively. The corresponding mean Cmax values of quetiapine in hair roots were 2.0, 5.9, and 14.7 ng/mg, and those of 7-hydroxyquetiapine were 1.0, 1.8, and 6.4 ng/mg. The mean half-lives of quetiapine at the three dosages in blood were 3.8 h, 5.0 h, and 6.0 h, and those in hair roots were 48.2 h, 41.5 h, and 162.3 h; for 7-hydroxyquetiapine, the values were 2.9 h, 4.1 h, and 4.2 h in blood and 77.1 h, 103.6 h, and 385.9 h in hair roots. The levels of quetiapine in blood and hair roots were higher than those of 7-hydroxyquetiapine, and there were significant positive correlations (p<0.05) between the concentrations of quetiapine and 7-hydroxyquetiapine in hair roots and the respective doses within 24 h and 48 h. Quetiapine and 7-hydroxyquetiapine could still be detected in some guinea pigs even after 28 days, which means that drugs remain in the hair roots longer than in the blood. This finding shows that hair roots could be a good alternative or supplemental matrix to common biological samples such as blood and urine, as hair roots substantially extend the detection window from days to months. Moreover, quetiapine and 7-hydroxyquetiapine were detected within 15min after administration in hair roots, which also suggests that the drug enters the hair roots quickly. Therefore, hair root analysis may be a good choice to detect acute poisoning and single-dose administration if other matrices are unavailable or to provide complementary information for other matrices.

Timing and Appearance of Postmortem Root Banding in Nonhuman Mammals.

A study was undertaken using nonhuman mammal specimens to better understand environmental influences on postmortem hair root band (PMRB) formation and to see whether PMRBs would occur in nonhuman mammal hairs in a similar fashion to human hairs. Carcasses from surrounding roadways were the primary source of specimens for this study, augmented by donated deceased domestic pets. Sections of pelt from each specimen were placed in controlled environmental conditions while the remainder of the carcass was left in a secure outdoor setting. Hair samples were collected daily from outdoor and control specimens and examined for evidence of PMRBs. Several environmental factors were also recorded on a daily basis. Results demonstrate PMRBs can occur in nonhuman mammal hairs, and they have microscopic characteristics similar to human PMRBs. Factors found to correlate with PMRB formation include postmortem interval, temperature, pH, and the formation and subsequent volatilization of ammonia from the surrounding tissue.

A Review and Conceptual Model of Factors Correlated with Postmortem Root Band Formation.

It is generally accepted within the forensic trace evidence community that a postmortem root band (PMRB) can appear in the root of hairs attached to remains during decomposition. Presently, the specific sequences of events and/or exact molecular signals that lead to the formation of a PMRB are not well understood. The published literature addressing the abiotic and biotic factors that correlate with the formation of PMRBs is reviewed and a conceptual model for the formation of PMRBs is proposed.

Heterorhizy and fine root architecture of rabbiteye blueberry (Vaccinium virgatum) softwood-cuttings.

All fine root systems consist of individual fine roots. Individual roots have morphological, anatomical, and functional heterogeneity (heterorhizy). Heterorhizy plays crucial roles in plant ecosystems. However, in many species, the heterorhizy and fine root system architecture based on individual root units are unclear. This study investigated heterorhizy along the root system architecture of Vaccinium virgatum Ait (rabbiteye blueberry) softwood-cuttings (propagated from annual shoots in growing season) using protoxylem groups (PGs), a classification according to the number of protoxylem poles, as an indicator of individual root traits. Individual roots of rabbiteye blueberry varied from monarch to heptarch. The frequency of roots with larger number of PGs decreased but those with smaller number of PGs increased from adventitious roots toward lateral roots with different branching levels. This architecture were stable among cultivars, collecting position of the cuttings, or indole acetic acids treatment. Individual root sizes and secondary growth were positively correlated with the PGs. These results indicate that branching itself strongly and broadly controls individual root traits. The individual roots were classified into two types: monarch and diarch roots with small size and lacking secondary growth (thought to be hair roots in core Ericaceae) and triarch or more PG roots with large size and showing secondary growth. These heterogeneous individual roots responded differently to the experimental factors. In particular, elongation of the large roots significantly contributed to increased total root length. These results mean that heterorhizic plasticity is a determinant of root system development and heterorhizic variation exists even under practical cutting condition. In conclusion, we demonstrated heterorhizy of rabbieye blueberry cuttings based on the strong relationships of PG, individual root morphology and growth potential, and root system architecture. This study also supports strong connection between root morphology and functional roles intermediated by the PG.

Microscopical characterization of known postmortem root bands using light and scanning electron microscopy.

A postmortem root band (PMRB) is a distinct microscopic feature that is postulated to occur in hair remaining in the follicle during the postmortem interval [1] (Petraco et al., 1998). The scientific validity of this premise has been highlighted in two recent high-profile criminal cases involving PMRBs [2,3] (State of Florida v. Casey Marie Anthony, 2008; People v. Kogut, 2005). To better understand the fundamental aspects of postmortem root banding, the microscopical properties of known PMRBs1 were characterized by light microscopy, and scanning electron microscope (SEM) imaging of microtomed sections of hairs showing root banding. The results from this study show that the appearance of the PMRB may be due to the degradation of the chemically labile, non-keratin intermacrofibrillar matrix (IMM) in the pre-keratin/keratogenous region of anagen hairs. In addition, this degradation is confined to the cortex of the hair, with no apparent damage to the layers of the cuticle. These results could provide valuable information for determining the mechanism of band formation, as well as identify a set of microscopic features that could be used to distinguish hairs with known PMRBs from similarly looking environmentally degraded hairs.

Detection of hair root miR-19a as a novel diagnostic marker for psoriasis.

BACKGROUND: Objective biomarkers that reflect the diagnosis and disease activity have not been in clinical use for psoriasis. OBJECTIVES: We investigated the hair root miR-19a levels, regulatory microRNA of TNF-α, and evaluated the possibility that miR-19a can be a biomarker of psoriasis. MATERIALS AND METHODS: microRNAs were extracted from hair roots of patients with psoriasis (n = 18) and healthy controls (n = 22). Samples from 10 atopic dermatitis patients and 4 dermatomyositis patients were also included as the disease controls. miR-19a levels were determined by quantitative real-time PCR. RESULTS: Hair root levels of miR-19a were significantly up-regulated only in psoriasis compared with normal controls. In characteristics (ROC) curve analysis for hair root miR-19a, to distinguish psoriasis patients from normal subjects, the areas under curve (AUC) was 0.87. Relative miR-19a levels were inversely and significantly correlated with duration between symptom onset and the first visit to the hospital in psoriasis patients. CONCLUSIONS: Our results indicated hair root miR-19a levels are effective as a disease marker.

DNA damage in hair root cells as a biomarker for gamma ray exposure.

The purpose of the present research is to examine whether human hair root cells can be used for dose assessment after in vitro exposure to ionizing radiation. Hair root samples plucked from random head regions were collected from 5 healthy human subjects. Some of these hair samples were used as control and some were irradiated with 0.5-5Gy of gamma ray using a Cs-137 gamma irradiator at a dose rate of 0.14Gy/s. DNA damage (single-strand breaks) was determined in hair root cells of these samples using the comet assay technique. The comet assay parameters, tail length (TL) and tail moment (TM), showed a significant increase (p<.05) in single-strand DNA breaks in hair roots cells of the exposed samples compared to control. A linear dose-effect relationship was observed when tail moment or tail length was plotted against the log of the radiation dose. This research suggests a possible use of human hair root cell DNA damage as a biomarker especially for low dose radiation.

Inoculum potential of ericoid endophytes of Western Australian heaths (Epacridaceae).

The nature and location of infective inocula of ericoid endophytes were examined in habitat soil sampled dry during midsummer from different depths down the rooting profile of an Epacridaceae-rich mediterranean-type ecosystem in south-western Australia. Efficacy of soil inocula was tested using aseptically germinated seedlings of Lysinema ciliatum R. Br. grown in a glasshouse. Hair roots, the principal structures colonized by endophytes, constituted c. 70% of the total length of root systems formed under glasshouse culture. Colonization of these hair roots by endophytes was greatest (17%) when seedlings had been inoculated with habitat soil from the upper 24 cm zone and declined to less than 1% following inoculation with soil obtained from a depth of 36 cm and beyond. By contrast, sampling of a naturally growing epacrid (Leucopogon conostephioides D.C.) at the same study site during the wet midwinter growing season showed uniformly high (34-43 %) infection of hair roots down to maximum rooting depth at 70 cm. The infectivity of sieved soil fractions from bulk habitat soil was considerably greater (mean of 17 % hair root infection) for glasshouse-cultured Lysinema ciliatum inoculated with the 251-305 µm particle size fraction than for that inoculated with coarser (306-5000 µm) and finer (39-250 µm) sieve fractions (0-6% infection). Dilution of bulk soil with sterilized soil indicated maximum infection at 1:16 dilution, declining to negligible infectivity at a dilution of 1:100. The data support the hypothesis that inoculum persists through summer principally in relatively coarse fractions of organic matter near the soil surface. With the onset of autumn rains, downward mycelial growth emanating from this upper zone rapidly recolonizes the soil profile and eventually promotes extensive colonization of hair roots produced that season by the epacrid root system.