Stability of inflammation markers in human blood collected using volumetric absorptive microsampling (VAMS) under typical laboratory storage temperatures.

Dried blood spots (DBS) collected on filter paper such as Guthrie cards are stored for years at room temperature. The assumption is that once dried, the samples remain stable and quantifiable indefinitely since the metabolites these were initially designed to measure, are known for their extended stability. The concentration of other blood proteins such as cytokines, however, are known to vary with storage even in liquid samples stored at -80 °C for extended periods of time. We sought to determine if cytokines are stable for up to 5 months when stored as a dried blood sample using volumetric absorptive microsampling (VAMS) devices. To test this, blood was collected from 4 healthy participants, spiked with recombinant cytokines, and collected into 30 µL VAMS devices. These prepared VAMS devices were stored at room temperature, 4 °C, or -20 °C for up to 5 months and matching VAMS liquid extracts were stored at -80 °C for the same period of time. At each timepoint, the samples were extracted from the VAMS devices and the extracts were analysed by Luminex® for quantification of up to 31 cytokines. These methods were also tested in a remote clinical study over a period of up to 8 months. Cytokine analysis revealed that room temperature, the current standard for DBS and VAMS storage, performed the poorest out of all storage temperatures with significant losses in 13/21 analytes compared to 4 °C at 5 months. Storage at 4 °C or colder performed well for the majority of analytes tested, however out of those, the optimal storage temperature differed for each analyte. There were a small number of analytes that performed poorly regardless of storage conditions and for fractalkine, this was found to be caused by inefficient recovery during extraction. Cytokine concentrations from finger-prick samples were also found to be much more variable that those in venous blood samples. Our results highlight the need to understand the stability of analytes of interest before committing to longitudinal collection and storage of samples in VAMS devices. These data give confidence that storage at 4 °C or colder was beneficial for cytokine stability. Wherein 25/31 cytokines were quantifiably stable at -20 °C when stored for 3 months and 17/21 were quantifiably stable after 5 months when stored at 4 °C.

Medial frontal GABA is lower in older schizophrenia: a MEGA-PRESS with macromolecule suppression study.

Gamma-butyric acid (GABA) dysfunction has been implicated in the pathophysiology of schizophrenia and its cognitive deficits. Proton magnetic resonance spectroscopy (MRS) was used to test the hypothesis that older participants with schizophrenia have lower anterior cingulate GABA levels compared with older control participants. One-hundred forty-five participants completed this study. For detection of GABA, spectra were acquired from the medial frontal/anterior cingulate cortex using a macromolecule-suppressed MEGA-PRESS sequence. Patients were evaluated for psychopathology and all participants completed neuropsychological tests of working memory, processing speed and functional capacity. GABA levels were significantly lower in the older participants with schizophrenia (n=31) compared with the older control (n=37) group (P=0.003) but not between the younger control (n=40) and schizophrenia (n=29) groups (P=0.994). Age strongly predicted GABA levels in the schizophrenia group accounting for 42% of the variance, but the effect of age was less in the control group accounting for 5.7% of the variance. GABA levels were specifically related to working memory but not processing speed performance, functional capacity, or positive or negative symptom severity. This is the largest MRS study of GABA in schizophrenia and the first to examine GABA without macromolecule contamination, a potentially significant issue in previous studies. GABA levels more rapidly declined with advancing age in the schizophrenia compared with the control group. Interventions targeted at halting the decline or increasing GABA levels may improve functional outcomes and quality of life as patients with schizophrenia age.

Developmental changes in genetic and environmental influences on Chinese child and adolescent anxiety and depression.

BACKGROUND: Twin and family studies using Western samples have established that child and adolescent anxiety and depression are under substantial genetic, modest shared environmental, and substantial non-shared environmental influences. Generalizability of these findings to non-Western societies remains largely unknown, particularly regarding the changes of genetic and environmental influences with age. The current study examined changes in genetic and environmental influences on self-reported anxiety and depression from late childhood to mid-adolescence among a Chinese twin sample. Sex differences were also examined. METHOD: Self-reported anxiety and depression were collected from 712 10- to 12-year-old Chinese twins (mean = 10.88 years, 49% males) and again 3 years later. Quantitative genetic modeling was used to examine developmental changes in genetic and environmental influences on anxiety and depression, and sex differences. RESULTS: Heritability of anxiety and depression in late childhood (23 and 20%) decreased to negligible in mid-adolescence, while shared environmental influences increased (20 and 27% to 57 and 60%). Shared environmental factors explained most of the continuity of anxiety and depression (75 and 77%). Non-shared environmental factors were largely time-specific. No sex differences were observed. CONCLUSIONS: Shared environmental influences might be more pronounced during the transition period of adolescence in non-Western societies such as China. Future research should examine similarities and differences in the genetic and environmental etiologies of child and adolescent internalizing and other psychopathology in development between Western and non-Western societies.

Genetic-geographic correlation revealed across a broad European ecotypic sample of perennial ryegrass (Lolium perenne) using array-based SNP genotyping.

KEY MESSAGE: Publically available SNP array increases the marker density for genotyping of forage crop, Lolium perenne. Applied to 90 European ecotypes composed of 716 individuals identifies a significant genetic-geographic correlation. Grassland ecosystems are ubiquitous across temperate and tropical regions, totalling 37% of the terrestrial land cover of the planet, and thus represent a global resource for understanding local adaptations to environment. However, genomic resources for grass species (outside cereals) are relatively poor. The advent of next-generation DNA sequencing and high-density SNP genotyping platforms enables the development of dense marker assays for population genetics analyses and genome-wide association studies. A high-density SNP marker resource (Illumina Infinium assay) for perennial ryegrass (Lolium perenne) was created and validated in a broad ecotype collection of 716 individuals sampled from 90 sites across Europe. Genetic diversity within and between populations was assessed. A strong correlation of geographic origin to genetic structure was found using principal component analysis, with significant correlation to longitude and latitude (P < 0.001). The potential of this array as a resource for studies of germplasm diversity and identifying traits underpinning adaptive variation is highlighted.

Tumour MLH1 promoter region methylation testing is an effective prescreen for Lynch Syndrome (HNPCC).

BACKGROUND AND AIMS: Lynch syndrome (LS) patients have DNA mismatch repair deficiency and up to 80% lifetime risk of colorectal cancer (CRC). Screening of mutation carriers reduces CRC incidence and mortality. Selection for constitutional mutation testing relies on family history (Amsterdam and Bethesda Guidelines) and tumour-derived biomarkers. Initial biomarker analysis uses mismatch repair protein immunohistochemistry and microsatellite instability. Abnormalities in either identify mismatch repair deficiency but do not differentiate sporadic epigenetic defects, due to MLH1 promoter region methylation (13% of CRCs) from LS (4% of CRCs). A diagnostic biomarker capable of making this distinction would be valuable. This study compared two biomarkers in tumours with mismatch repair deficiency; quantification of methylation of the MLH1 promoter region using a novel assay and BRAF c.1799T>A, p.(Val600Glu) mutation status in the identification of constitutional mutations. METHODS: Tumour DNA was extracted (formalin fixed, paraffin embedded, FFPE tissue) and pyrosequencing used to test for MLH1 promoter methylation and presence of the BRAF c.1799T>A, p.(Val600Glu) mutation 71 CRCs from individuals with pathogenic MLH1 mutations and 73 CRCs with sporadic MLH1 loss. Specificity and sensitivity was compared. FINDINGSS: Unmethylated MLH1 promoter: sensitivity 94.4% (95% CI 86.2% to 98.4%), specificity 87.7% (95% CI 77.9% to 94.2%), Wild-type BRAF (codon 600): sensitivity 65.8% (95% CI 53.7% to 76.5%), specificity 98.6% (95% CI 92.4% to 100.0%) for the identification of those with pathogenic MLH1 mutations. CONCLUSIONS: Quantitative MLH1 promoter region methylation using pyrosequencing is superior to BRAF codon 600 mutation status in identifying constitutional mutations in mismatch repair deficient tumours.

Mutational bias provides a model for the evolution of Huntington's disease and predicts a general increase in disease prevalence.

Huntington's disease (HD) correlates with abnormal expansion in a block of CAG repeats in the Huntington's disease gene. We have investigated HD evolution by typing CAG alleles in several human populations and in a variety of primates. We find that human alleles have expanded from a shorter ancestral state and exhibit unusual asymmetric length distributions. Computer simulations are used to show that the human state can be derived readily from a primate ancestor, without the need to invoke natural selection. The key element is a simple length-dependent mutational bias towards longer alleles. Our model can explain a number of empirical observations, and predicts an ever-increasing incidence of HD.

Innate immunity: Looking beyond T-cells in radiation and immunotherapy combinations.

Radiation therapy is an established and effective anti-cancer treatment modality. Extensive pre-clinical experimentation has demonstrated that the pro-inflammatory properties of irradiation may be synergistic with checkpoint immunotherapy. Radiation induces double-stranded DNA breaks (dsDNA). Sensing of the dsDNA activates the cGAS/STING pathway, producing Type 1 interferons essential to recruiting antigen-presenting cells (APCs). Radiation promotes cytotoxic CD8 T-cell recruitment by releasing tumour-associated antigens captured and cross-presented by surveying antigen-presenting cells. Radiation-induced vascular normalisation may further promote T-cell trafficking and drug delivery. Radiation is also immunosuppressive. Recruitment of regulatory T cells (Tregs) and innate cells such as myeloid-derived suppressive cells (m-MDSCs) all counteract the immunostimulatory properties of radiation. Many innate immune cell types operate at the interface of the adaptive immune response. Innate immune cells, such as m-MDSCs, can exert their immunosuppressive effects by expressing immune checkpoints such as PD-L1, further highlighting the potential of combined radiation and checkpoint immunotherapy. Several early-phase clinical studies investigating the combination of radiation and immunotherapy have been disappointing. A greater appreciation of radiotherapy's impact on the innate immune system is essential to optimise radioimmunotherapy combinations. This review will summarise the impact of radiotherapy on crucial cells of the innate immune system and vital immunosuppressive cytokines.

Milk-derived or recombinant transforming growth factor-beta has effects on immunological outcomes: a review of evidence from animal experimental studies.

Identified factors from milk have been shown to improve health outcomes. One specific factor, transforming growth factor-Beta (TGF)-ß, has been identified previously as having the potential to impact on immunological outcomes in the newborn offspring. The primary objective of this review was to examine the published studies that have considered TGF-ß in association with immunological outcomes of experimental models. We hypothesized that oral administration of TGF-ß (through human milk, cow's milk, infant formula) or recombinant TGF-ß delivered via gavage, may down-regulate immune activation in newborn offspring. Animal experimental studies were identified through MEDLINE, CAB Abstracts, Biological Abstracts and Scopus. Selection criteria included well-described animal populations, sample and study design, source of TGF-ß, age and immunological outcomes measured and effect size. The findings were summarized temporally in tabular format, giving an overall measure of effect based on the literature available since 1994. Animal experimental studies (n=13) were included in the review to determine an association between maternal TGF-ß and immunological outcomes. Overall 92% of these studies (12/13) showed a positive association with TGF-ß1 or TGF-ß2, demonstrating protection against immunologically related outcomes in early life in an animal model. TGF-ß is important in developing and maintaining appropriate immune responses in the offspring. TGF-ß delivered orally to neonatal animals provides protection against adverse immunological outcomes, corroborating and supporting findings from human studies. Animal studies provide important clues to the pathogenesis and therapeutics of immune activation and allergy in early childhood. TGF-ßs are important growth factors involved in maintaining homeostasis in the intestine, regulating inflammation and allergy development and promoting oral tolerance in infants. Thus, taken as a whole, these and our other findings suggest that this cytokine in milk may influence the development of immunological outcomes in offspring.

The impact of substance abuse on osteoporosis screening and risk of osteoporosis in women with psychotic disorders.

UNLABELLED: Review of the 1-year prevalence of screening for osteoporosis and of osteoporosis or idiopathic fracture in Maryland Medicaid administrative records found that screening rates did not differ among women in the control population, women with psychosis, and women with major mood disorders, but were reduced compared to controls in women with substance use disorder, with or without psychosis. Prevalence of osteoporosis was increased compared to controls in women with major mood disorders or women over 55 dually diagnosed with psychosis and substance use disorder. INTRODUCTION: Osteoporosis is a major public health concern. Substance abuse and psychosis may be risk factors, however, frequency of screening and disease risk in women with psychotic disorders and substance use disorder (SUD) remains unknown. METHODS: This study examined rates (FY 2005) of osteoporosis screening and disease risk in Medicaid enrolled women aged 50 to 64 (N = 18,953). Four diagnostic groups were characterized: (1) psychosis, (2) SUD, (3) major mood disorder, and (4) controls. The interaction of psychosis and SUD on screening and disease prevalence of osteoporosis was tested. RESULTS: The prevalence of osteoporosis across the entire population was 6.7%. Four percent of those without an osteoporosis diagnosis received osteoporosis screening with no notable differences between psychosis and controls. Those with SUD, however, had a significant reduction in screening compared to controls (OR = 0.61, 95% CI = 0.40-0.91, p = 0.016). Women with a major mood disorder were more likely to have osteoporosis in their administrative record (OR = 1.32, 95% CI = 1.03-1.70, p = 0.028) compared to controls. Those who were dually diagnosed (SUD and psychosis) in the oldest ages (55-64 years) had a markedly higher prevalence of osteoporosis compared to controls (OR = 6.4 CI = 1.51-27.6, p = 0.012), whereas this interaction (SUD and psychosis) was not significant in the entire population over age 49. CONCLUSIONS: Osteoporosis screening in the Medicaid population is significantly lower for women with SUD, after adjusting for age, race, and Medicaid enrollment category. The prevalence of osteoporosis appears markedly elevated in those with major mood disorders and those over age 55 dually diagnosed with schizophrenia and SUD.

SARS-CoV-2 decontamination of skin with disinfectants active during and after application.

BACKGROUND: The coronavirus disease 2019 pandemic has resulted in high levels of exposure of medical workers to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Hand decontamination is one of the actions recommended to reduce the risk of infection. AIM: Two disinfectants - BIAKOS antimicrobial skin and wound cleanser (AWC) and AWC2 (Sanara MedTech, Fort Worth, TX, USA) - were tested to determine whether they can inactivate SARS-CoV-2 upon contact or as a coating applied before contact with the virus. METHODS: The ability of AWC and AWC2 to inactivate SARS-CoV-2 was tested in liquid and dried form on plastic surfaces and porcine skin. FINDINGS: AWC and AWC2 were effective in reducing the infectious titre of SARS-CoV-2 in liquid form during application and in dried form 4 h after application. Virus on skin was reduced up to 2 log10-fold and 3.5 log10-fold after treatment with AWC and AWC2, respectively. CONCLUSION: Application of AWC and AWC2 to skin reduces the level of SARS-CoV-2 and the risk of infection.

Remission in schizophrenia: the relationship to baseline symptoms and changes in symptom domains during a one-year study.

The concepts of partial recovery and remission have become increasingly important for the evaluation of the effectiveness of schizophrenia therapeutics. The relationship of baseline symptoms and changes in symptoms to remission of psychosis was evaluated. Fifty-six outpatients with residual schizophrenia completed a double-blind trial of olanzapine versus haloperidol and were then enrolled into a one-year open-label trial of olanzapine. Out of these 56 subjects, 13 (23%) met remission criteria at the beginning of the open-label treatment and were excluded. During the one-year study, 7/43 (16%) subjects met remission criteria. These subjects had significantly lower baseline ratings for tardive dyskinesia (TD) than subjects who did not achieve remission (1.8 +/- 1.5 vs. 4.2 +/- 4.6, P = 0.03). As expected, remitted subjects had significantly greater improvements in Brief Psychiatric Rating Scale total scores, positive subscale scores and scale for the Assessment of Negative Symptoms total scores. Remitted subjects also experienced a significantly greater improvement in depressive symptoms (P = 0.001), activation (P = 0.005), and Clinical Global Impressions scores (P < 0.001), as well as greater improvements in extrapyramidal symptoms (P = 0.007) and TD (P < 0.001). These results suggest that the relationship of depressive symptoms and improved side effects to the construct of remission in schizophrenia may deserve special attention. Future studies should aim to relate remission criteria to functional outcomes, cognition, and other important symptom domains.

X-linked ichthyosis (steroid sulfatase deficiency) is associated with increased risk of attention deficit hyperactivity disorder, autism and social communication deficits.

BACKGROUND: X-linked ichthyosis (XLI) (steroid sulfatase deficiency) is caused by deletions or point mutations of the steroid sulfatase (STS) gene on chromosome Xp22.32. Deletions of this region can be associated with cognitive behavioural difficulties including autism. Animal work suggests the STS gene may be involved in attentional processes. We have therefore undertaken a systematic study of autism and attention deficit hyperactivity disorder (ADHD) in boys with XLI. METHODS: Cases of XLI were recruited from families originally ascertained when pregnancies with STS deficiency were identified through a routine maternal screening programme. Boys with XLI were assessed for ADHD and autism using standardised questionnaires and interviews. Deletions of the STS gene were identified and characterised by analysis of genomic DNA and/or fluorescent in situ hybridisation. RESULTS: 25 boys with XLI were assessed for autism and ADHD. 40% fulfilled DSM-IV criteria for a diagnosis of ADHD, 80% of which were inattentive subtype. ADHD diagnoses were present in those with both deletions and presumed point mutations of STS. Additionally, five boys, from three unrelated families, fulfilled criteria for an autistic spectrum disorder or related language/communication difficulty, and all had an unusually large deletion of the STS gene with loss of the neuroligin 4 (NLGN4) gene. None of the boys with the typical deletion or presumed point mutations of STS demonstrated autistic difficulties. CONCLUSIONS: STS deficiency may be a risk factor for ADHD with predominantly inattentive symptoms. Boys with XLI and large deletions encompassing STS and NLGN4 are at increased risk of developing autism and related disorders.

Cost analysis of biomarker testing for mismatch repair deficiency in node-positive colorectal cancer.

BACKGROUND: Microsatellite instability (MSI) in colorectal cancer is caused by defective DNA mismatch repair (MMR). It is present in 15 per cent of sporadic colorectal cancers owing to epigenetic mutL homologue 1 (MLH1) inactivation. The evidence suggests that patients with tumours caused by defective DNA MMR do not benefit from 5-fluorouracil (5-FU)-based chemotherapy. METHODS: The proportion of cancers with defective DNA MMR identified by MSI analysis or immunohistochemistry was calculated from published data. The cost of analysis was compared with the potential savings if 5-FU-based chemotherapy was not administered to these patients. RESULTS: Some 16.3 per cent of sporadic colorectal cancers had defective DNA MMR. Immunostaining for MLH1 and mutS homologue 2 (MSH2) had a sensitivity of 92.4 per cent and a specificity of 99.6 per cent for identifying MSI-high tumours. The strongest predictive variable was right-sidedness, with positive and negative predictive values of 0.329 and 0.948 respectively. If 5-FU-based chemotherapy were not administered, potential savings of up to pound 1.2 million per 1000 patients tested could be made. Costs would be higher if alternative chemotherapeutic regimens were substituted as a result of testing. CONCLUSION: Knowledge of MMR status may enable participation in trials of non-5-FU-based chemotherapy. The cost of MMR testing may be offset by more efficient use of chemotherapy.

Who should be followed up after transanal endoscopic resection of rectal tumours?

OBJECTIVE: To determine follow-up requirements following transanal endoscopic microsurgery (TEM) for rectal tumours based on clinical and histopathological assessment of resection specimens. METHOD: A consecutive series of 117 patients undergoing TEM between 1997 and 2005 was studied. The excised specimens were classified as intact with clear surgical resection margins, macroscopically intact specimens with microscopically involved resection margins or piecemeal. Recurrence rates were determined for the three groups. RESULTS: Of the 117 procedures performed, 80 were for benign disease and 37 for malignancy. Within the benign group 39 (49%) resections were intact with clear surgical resection margins and yielded zero recurrences; 22 (27%) resections were macroscopically intact with microscopically involved surgical resection margin and yielded two recurrences; and 19 (24%) resections were piecemeal and yielded eight recurrences. Within the malignant group all 37 patients had resection specimens which were intact with clear surgical resection margins. Two patients had immediate salvage surgery. Of the 35 who went on to long-term follow-up post-TEM (0.6-8.1 years, median 4) four developed recurrent cancer (two local with submucosal disease and two liver metastases). CONCLUSION: For benign rectal neoplasms, resection of an intact specimen with histologically clear surgical resection margins was associated with no observed mucosal recurrence. Local recurrence after TEM is significantly more frequent when histological examination reveals involved margins or when resection is piecemeal. Early endoscopic follow up is required for the latter two groups. Local recurrence for malignant cases was submucosal and detected by palpation.

VersaStep trocar hernia rate in unclosed fascial defects in bariatric patients.

OBJECTIVE: Use of the VersaStep trocar system (US Surgical, Norwalk, CT) has the perceived advantage of minimal trocar-related hernias in patients undergoing Roux-en-Y gastric bypass surgery (RYGB). We performed a retrospective review of our last 747 consecutive operative procedures using these trocars. METHODS AND PROCEDURES: The patient population was 747 consecutive patients who underwent laparoscopic RYGB at Duke University Health System Weight Loss Surgery Center from January 2002 through April 2005. A total of 3735 radially expanded trocar sites were used. VersaStep trocars were used in all cases. The port configuration included one supraumbilical Hasson port, two 12-mm ports, and three 5-mm ports. The Hasson port was closed with a figure-of-eight number 1 Polysorb suture. All other trocar sites had no fascial closure. Intestinal anastomoses were created with a linear stapler in all of the laparoscopic cases, with hand suturing of the residual enterotomy. The fascial incisions were therefore not extended to accommodate an EEA stapler. The charts were reviewed for occurrence of subsequent trocar site hernias. RESULTS: There were no hernias at any of the VersaStep trocar sites-an incidence of 0%. There were nine incisional hernias at the Hasson port site which later required surgical repair-an incidence of 1.20%. CONCLUSIONS: There were no hernias detected at any of the 1494 12-mm or 2241 5-mm VersaStep trocar sites, despite lack of suture closure. At the Hasson port site, there was a hernia incidence of 1.20%. In the bariatric RYGB population, routine suture closure of the fascia or muscle is not necessary when using radially expanding VersaStep trocars.

Use of mask continuous positive airway pressure in a preterm infant presenting with bilateral cleft lip and palate.

This report highlights innovative ways of overcoming difficulties in delivering effective continuous positive airway pressure in an extremely preterm baby with bilateral cleft lip and cleft palate.

Assay of 855 test chemicals in ten tester strains using a new modification of the Ames test for bacterial mutagens.

Determination of mutagenic activity in bacterial systems has become accepted as an initial step in the evaluation of the carcinogenic potential of new chemicals. In this paper, a bacterial mutagen screening technique is described in which chemicals can be tested in 10 tester strains over a 10,000-fold concentration gradient both with and without metabolic activation. Using this assay, 855 chemicals were tested, and 182 were found to be mutagenic in one or more of the tester strains. Included were 299 chemicals used in chemical manufacturing or laboratory synthesis. Of these, 20% gave a positive response in one or more strains. The high rate of positives undoubtedly reflects the high chemical reactivity of compounds in this group. In contrast, when 261 organic chemicals which were synthesized for evaluation as potential pharmaceutical or agricultural products were tested, only 8% were identified as mutagenic. The Salmonella typhimurium tester strains TA98 and TA1538 proved to be very reliable and efficient in detecting and identifying frame-shift mutagens. TA100 was the most sensitive tester strain, detecting 142 of the 182 mutagens encountered in the study. However, since TA100 detected both base substitution mutagens and frame-shift mutagens, this tester strain was not suitable for the specific identification of base substitution mutagens. Base substitution mutagens were more reliably detected by Escherichia coli tester strains WP2 and WP2 uvrA- than they were by S. typhimurium strains G46 and TA1535. The data obtained when mutagens are tested by the concentration gradient procedures can include (a) the activity spectrum in tester strains, (b) identification as either frame-shift or base substitution mutagens, (c) the minimal concentration at which auxotroph growth is inhibited, and (d) mutagenic potency in terms of minimal concentration at which mutagenicity is observed. The data obtained have been found to be of immediate use. For example, with manufacturing intermediates the data have been combined with other toxicity data and used as a basis for setting safety standards for handling such compounds in the workplace. In addition, positive bacterial mutagenicity data on selected members of new series of organic compounds can serve to alert the chemist early to the possibility that the compounds may possess undesirable toxic properties, particularly carcinogenicity. Also, this type of data should be of great value both in the planning and in the interpretation of other in vitro tests designed to evaluate the potential carcinogenicity in mammals of chemicals found to be positive in bacterial tests.

Disposition and tissue levels of [3H]vindesine in rats.

The excretion, blood levels, and tissue distribution of [3H]vindesine have been studied in the rat. After an i.v. administration of 500 microgram/kg. [3H]vindesine was found to be distributed very rapidly to tissues. After the distribution phase, blood levels declined with a half-life near 10 hr. Excretion was mainly via the bile, and [3H]vindesine and its metabolites in bile were poorly reabsorbed in the gastrointestinal tract. Levels were relatively high in most tissues studied but appeared to be efficiently cleared from all tissues except thymus and testes. Uptake into peripheral nerves was considerably higher than into the central nervous system.

Germplasm dynamics: the role of ecotypic diversity in shaping the patterns of genetic variation in Lolium perenne.

Perennial ryegrass (Lolium perenne) is the most widely grown temperate grass species globally. Intensive plant breeding in ryegrass compared to many other crops species is a relatively recent exercise (last 100 years) and provides an interesting experimental system to trace the extent, impact and trajectory of undomesticated ecotypic variation represented in modern ryegrass cultivars. To explore germplasm dynamics in Lolium perenne, 2199 SNPs were genotyped in 716 ecotypes sampled from 90 European locations together with 249 cultivars representing 33 forage/amenity accessions. In addition three pseudo-cross mapping populations (450 individual recombinants) were genotyped to create a consensus genetic linkage map. Multivariate analyses revealed strong differentiation between cultivars with a small proportion of the ecotypic variation captured in improved cultivars. Ryegrass cultivars generated as part of a recurrent selection programme (RSP) are strongly associated with a small number of geographically localised Italian ecotypes which were among the founders of the RSP. Changes in haplotype frequency revealed signatures of selection in genes putatively involved in water-soluble carbohydrate (WSC) accumulation (a trait selected in the RSP). Retrospective analysis of germplasm in breeding programmes (germplasm dynamics) provides an experimental framework for the identification of candidate genes for novel traits such as WSC accumulation in ryegrass.

Increased variability in Apc(Min)/+ intestinal tissue can be measured with microultrasound.

Altered tissue structure is a feature of many disease states and is usually measured by microscopic methods, limiting analysis to small areas. Means to rapidly and quantitatively measure the structure and organisation of large tissue areas would represent a major advance not just for research but also in the clinic. Here, changes in tissue organisation that result from heterozygosity in Apc, a precancerous situation, are comprehensively measured using microultrasound and three-dimensional high-resolution microscopy. Despite its normal appearance in conventionally examined cross-sections, both approaches revealed a significant increase in the variability of tissue organisation in Apc heterozygous tissue. These changes preceded the formation of aberrant crypt foci or adenoma. Measuring these premalignant changes using microultrasound provides a potential means to detect microscopically abnormal regions in large tissue samples, independent of visual examination or biopsies. Not only does this provide a powerful tool for studying tissue structure in experimental settings, the ability to detect and monitor tissue changes by microultrasound could be developed into a powerful adjunct to screening endoscopy in the clinic.