The Early Life Microbiota Is Not a Major Factor Underlying the Susceptibility to Postweaning Diarrhea in Piglets

Postweaning diarrhea (PWD) in piglets impair welfare, induce economic losses and lead to overuse of antibiotics. The early life gut microbiota was proposed to contribute to the susceptibility to PWD. The objective of our study was to evaluate in a large cohort of 116 piglets raised in 2 separate farms whether the gut microbiota composition and functions during the suckling period were associated with the later development of PWD. The fecal microbiota and metabolome were analyzed by 16S rRNA gene amplicon sequencing and nuclear magnetic based resonance at postnatal day 13 in male and female piglets. The later development of PWD was recorded for the same animals from weaning (day 21) to day 54. The gut microbiota structure and α-diversity during the suckling period were not associated with the later development of PWD. There was no significant difference in the relative abundances of bacterial taxa in suckling piglets that later developed PWD. The predicted functionality of the gut microbiota and the fecal metabolome signature during the suckling period were not linked to the later development of PWD. Trimethylamine was the bacterial metabolite which fecal concentration during the suckling period was the most strongly associated with the later development of PWD. However, experiments in piglet colon organoids showed that trimethylamine did not disrupt epithelial homeostasis and is thus not likely to predispose to PWD through this mechanism. In conclusion, our data suggest that the early life microbiota is not a major factor underlying the susceptibility to PWD in piglets. IMPORTANCE This study shows that the fecal microbiota composition and metabolic activity are similar in suckling piglets (13 days after birth) that either later develop post-weaning diarrhea (PWD) or not, which is a major threat for animal welfare that also causes important economic losses and antibiotic treatments in pig production. The aim of this work was to study a large cohort of piglets raised in separates environments, which is a major factor influencing the early life microbiota. One of the main findings is that, although the fecal concentration of trimethylamine in suckling piglets was associated with the later development of PWD, this gut microbiota-derived metabolite did not disrupt the epithelial homeostasis in organoids derived from the pig colon. Overall, this study suggests that the gut microbiota during the suckling period is not a major factor underlying the susceptibility of piglets to PWD.

Phenolic potential of new red hybrid grape varieties to produce quality wines and identification by the malvin

The hybrids are new varieties that are resistant to the cryptogamic diseases of vines, and they may be a good solution to the reduction of pesticide use. However, these new varieties have appeared recently and only few studies have been conducted to check the quality of the wine that they produce. In this study, wines originated from hybrids were chemically characterized (polyphenols, tannins, anthocyanins, and color analysis). Results show that their oenological parameters were close to those of the Vitis vinifera wines. The wines made from Vinifera (100%), with Vidoc, and all the resistant Bouquets studied are malvidin-3 glucoside dominant, and all the others hybrids varieties are cyanidin dominant. Furthermore, the hybrid wines had a higher concentration in condensed tannins and a lower one in molecular tannins compared with the Vitis vinifera wines, except for the Vidoc wines. As far as the anthocyanin content is concerned, the samples contained anthocyanin diglucosides, with the malvidin-3,5-diglucoside (malvin) the most abundant one. Also, their concentration in molecular anthocyanins were higher than the concentration in normal wines. The Vidoc wines do not contain any malvin. For the other wines, malvin co-eluted with cyanidin-3-O-glucoside and in this case, the cyanidin’s concentration was impressively higher than the Vidoc wines. The current OIV method gives different results for malvidol diglucoside compared to the use of an HPLC chromatography method (HPLC-DAD-QQQ). The current OIV method does not appear reliable in comparison with the HPLC method for detecting malvin. Finally, the hybrid wines had a darker blue/purplish color than the Vitis vinifera wines.

P11.64.A Long-term follow up and translational data from the ReoGlio phase Ib trial of GM-CSF and intravenous pelareorep (Reovirus) alongside standard of care in GBM

BACKGROUND

We previously reported safety data from a phase Ib, open-label study of intravenous oncolytic virus pelareorep with GM-CSF alongside standard chemoradiotherapy in newly diagnosed glioblastoma confirming that the combination is well tolerated. We now report on long-term follow up and analysis of translational samples from tumour and blood in a subset of patients.

METHODS

15 patients with newly diagnosed GBM were treated with GM-CSF 50μg subcutaneously on days 1-3 and intravenous pelareorep on days 4-5 in weeks 1 and 4 of chemoradiotherapy, and subsequently in week 1 of each adjuvant temozolomide course: 7 patients received 1x1010TCID50 (dose level 1); 8 received 3x1010TCID50 (dose level 2). The primary objective was to determine the maximum tolerated dose of pelareorep and GM-CSF with standard chemoradiotherapy. Following a protocol amendment we also collected survival data in all patients up to August 2021. Serial blood samples were taken from three patients, at baseline, during chemoradiotherapy and in the first adjuvant cycle. Peripheral blood mononuclear cells were analysed for immune checkpoint expression by flow cytometry, RNAseq gene expression and T-cell receptor clonality, whilst plasma cytokines were quantified by Luminex.

RESULTS

This combination was well tolerated with 87% of patients completing treatment as planned. Survival data analysis showed that median OS was 12.6 months in dose level 1 and 16.1 months in dose level 2, median OS for all patients was 13.1 months. The 24-month survival estimate for all patients was 25.0%, 16.7% for dose level 1 and 33.3% for dose level 2. One patient in dose level 1 remains alive at 43 months post registration without further treatment. Laboratory data showed that pelareorep infusion resulted in inflammatory cytokine and chemokine secretion, immune checkpoint modulation, and upregulation of inflammatory pathways. There was also increased peripheral clonal tumour-specific T-cell proliferation following pelareorep infusion.

CONCLUSION

Although based on small numbers, these long-term follow up data suggest this may be an active combination in a subset of GBM patients. Translational data confirm that pelareorep potentially activates tumour-targeting immune pathways in GBM, with consequential immune checkpoint modulation. These data support a combination clinical trial of pelareorep, radiotherapy and immune checkpoint blockade in GBM.

PSVIII-13 Utilization of a Mechanistic Model to Estimate the Mineral Deposition of Females and Entire Males Growing Pigs

Entire male (EM) production is increasing worldwide due to animal welfare regulations. The soft tissue growth and carcass composition of these animals were previously studied, but few data are available about mineral deposition. The objective in this study was to highlight, through modelling, potential differences in bone mineral deposition between female and EM, fed with identical diets. The data of 7 nutritional trials were used to simulate the mineral deposition in bones of EM and females. All diets were tested on both sexes and growth performances were reported. The trials started at about 32 kg of bodyweight and were divided into 2 phases: a growing phase (between 33 and 49 d, until 60 to 69 kg) and a finishing phase (between 47 and 61 d, until 110 to 125 kg). Protein and lipid depositions were calibrated following the InraPorc model principles. The minerals deposition in soft tissues and in bones were simulated according to a recent model predicting the utilization of minerals by growing pigs. The input data were the mean of each treatment, for each sex. The simulated bone mineral content (BMC) and bodyweight of the females and EM were comparable at the beginning of the trials. The BMC at the end of growing phase was less in EM than females (1,280 vs 1,298 g, P < 0.05), whereas bodyweight was equal. The BMC at the end of finishing phase tended to be less in EM than females (P = 0.10), and bodyweight was greater in EM than females (114 vs 116, P < 0.05).These results showed that during the growing phase, where the protein deposition increases quickly, the EM have less mineral in their bones than female. Therefore, with the same diet, these animals could be more sensitive to leg problems, which is reported in the field. These first results based on simulations showed that mineral requirements for EM are greater than females indicating that the mineral requirements must be adjusted according to the sex.

Gut Microbiota-Derived Metabolite Signature in Suckling and Weaned Piglets

The gut microbiota plays a key role in intestinal development at the suckling-to-weaning transition. The objective of this study was to analyze the production of metabolites by the gut microbiota in suckling and weaned piglets. We studied piglets raised in two separate maternity farms and weaned at postnatal day 21 in the same farm. The fecal metabolome (¹H nuclear magnetic resonance) and the microbiota composition (16S rRNA gene amplicon sequencing) and its predicted functions (PICRUSt2) were analyzed in the same piglets during the suckling period (postnatal day 13) and 2 days after weaning (postnatal day 23). The relative concentrations of the bacterial metabolites methylamine, dimethylamine, cadaverine, tyramine, putrescine, 5-aminovalerate, succinate, and 3-(4-hydroxyphenylpropionate) were higher during the suckling period than after weaning. In contrast, the relative concentrations of the short-chain fatty acids acetate and propionate were higher after weaning than during the suckling period. The maternity of origin of piglets also influenced the level of some bacterial metabolites (propionate and isobutyrate). The fecal metabolome signatures observed in suckling and weaned piglets were associated with specific microbiota-predicted functionalities, structure, and diversity. Gut microbiota-derived metabolites, which are differentially abundant between suckling and weaned piglets (e.g., short-chain fatty acids and biogenic amines), are known to regulate gut health. Thus, identification of metabolome signatures in suckling and weaned piglets paves the way for the development of health-promoting nutritional strategies, targeting the production of bacterial metabolites in early life.

PSV-1 Effects of the protein level on growth performance and carcass grading in fattening pig fed ad libitum

Reducing dietary crude protein (CP) with synthetic amino acids (AA) supplementation is beneficial for sustainable swine industry. However some discrepancies regarding the consequences on growth performance are observed. Therefore, this trial aimed to assess the effect of dietary CP level on growth performance of pigs from 35 to 113 kg BW. Growth performance of 63 pigs fed ad libitum and allocated to three groups (HH, MM and LL) was compared. Each group received one level of CP (‘H’ for High, ‘M’ for Medium and ‘L’ for Low) during growing (d0–d35) and finishing (d35–slaugther day) periods: 15.1%, 16.2%, 17.2% and 13.0%, 14.0%, 15.1% respectively. Diets were mostly based on wheat, corn and soybean meal. Within each feeding phase, diets were formulated to be similar in apparent total tract digestible phosphorus, net energy and standardized ileal digestible (SID) essential AA, the SID Lys levels being 0.95% and 0.78% during the growing and finishing period respectively. Data were analyzed using a linear model (R, 3.1.2) with individual as the experimental unit as feed intake, body weight and carcass grading were individually recorded. From d0 to d14 and from d35 to d63, average daily gain (ADG) and Growth:Feed ratio (G:F) were significantly reduced as the CP level decreased (P < 0.05) while average daily feed intake (ADFI) remained unaffected by the dietary treatments. From d14 to d35 and in late finishing period (d63-slaugther day), growth performance was not significantly affected by the dietary CP level. Over the 82-d of the experiment, G:F was significantly higher for ‘HH’ pigs (P < 0.01). Overall, ADG tended to be reduced as CP levels decreased (P = 0.10). There was no difference among treatments for parameters concerning carcass grading (lean meat percentage and meat yield). In conclusion, reducing CP levels while maintaining essential AA levels impaired growth performances of pigs.

Impact of diet deprivation and subsequent overallowance during gestation on lactation performance of primiparous sows

The impact of diet deprivation followed by overallowance during gestation on metabolic status of pregnant gilts and their lactation performance was determined. Gilts were fed a standard diet until day 27 of gestation and were subsequently reared under a control (CTL; n = 28) or an experimental (treatment, TRT; n = 26) dietary regimen. The experimental regimen provided 70% (restriction diet, RES) and 115% (overallowance diet, OVER) of the protein and NE contents provided by the CTL diet. The RES diet was given from days 28 to 74 of gestation followed by the OVER diet from day 75 until farrowing. Blood samples were obtained from all gilts on days 28, 75, and 110 of gestation, and on days 3 and 20 of lactation to measure concentrations of IGF-1, urea, FFA, and glucose. Milk samples were collected from 12 sows per treatment on day 19 of lactation and sow feed intake was recorded daily throughout lactation. Piglets were weighed at 24 h (after standardization of litter size), and on days 7, 14, and 21 (weaning). The TRT gilts gained less BW than CTL gilts (17.3 vs. 31.7 kg; P < 0.01) from days 28 to 75 of gestation and more BW (29.5 vs. 21.9 kg; P < 0.01) from days 75 to 110, but their overall gain from mating to day 110 was lower (61.4 vs. 67.2 kg; P < 0.05). Metabolic status during gestation was affected, with TRT gilts having less IGF-1 and urea, and more FFA than CTL gilts on day 75 (P < 0.01), and more urea on day 110 (P < 0.01). Growth rate of suckling piglets, sow lactation feed intake, and standard milk composition in late lactation (DM, fat, protein, lactose) were not affected by treatment (P > 0.10). In conclusion, diet deprivation of gilts as of day 28 of gestation followed by overfeeding from day 75 of gestation until farrowing did not improve lactation performance. It is likely that the compensatory growth that took place in late gestation was not adequate to illicit beneficial effects.

Rational Design of Bisubstrate-Type Analogues as Inhibitors of DNA Methyltransferases in Cancer Cells

Aberrant DNA hypermethylation of promoter of tumor suppressor genes is commonly observed in cancer, and its inhibition by small molecules is promising for their reactivation. Here we designed bisubstrate analogues-based inhibitors, by mimicking each substrate, the S-adenosyl-l-methionine and the deoxycytidine, and linking them together. This approach resulted in quinazoline-quinoline derivatives as potent inhibitors of DNMT3A and DNMT1, some showing certain isoform selectivity. We highlighted the importance of (i) the nature and rigidity of the linker between the two moieties for inhibition, as (ii) the presence of the nitrogen on the quinoline group, and (iii) of a hydrophobic group on the quinazoline. The most potent inhibitors induced demethylation of CDKN2A promoter in colon carcinoma HCT116 cells and its reactivation after 7 days of treatment. Furthermore, in a leukemia cell model system, we found a correlation between demethylation of the promoter induced by the treatment, chromatin opening at the promoter, and the reactivation of a reporter gene.

<b>A pre­liminary report on the impact of road kills on the herpetofauna species in Nilgiris, Tamil Nadu, India</b>

To know the situation of road hits of amphibians and reptile species, a survey was conducted during the period 02 June 2013 to 25 May 2014.  A total of 172 incidents of road kill of different species were noticed, representing 12 species of herpetofauna, including five amphibian species of the families Bufonidae, Dicroglossidae, Microhylidae and Rhacophoridae, and seven species of reptiles of the families Scincidae, Agamidae, Uropeltidae, Colubridae, Natricidae and Xenodermatidae.  Reptiles were the most affected group (60%), of which more than 79.61% of the road kills were snakes.  The most affected snake species were endemic Xylophis perroteti (64.63%). 

Improving the Transition From Oncology to Primary Care Teams: A Case for Shared Leadership

This article discusses the case of a 47-year-old woman who underwent primary therapy with curative intent for breast cancer. The case illustrates a number of failure events in transferring information and responsibility from oncology to primary care teams. The article emphasizes the importance of shared leadership, as multiple team members, dispersed in time and space, pursue their own objectives while achieving the common goal of coordinating care for survivors of cancer transitioning across settings. Shared leadership is defined as a team property comprising shared responsibility and mutual influence between the patient and the patient’s family, primary care providers, and oncology teams, whereby they lead each other toward quality and safety of care. Teams, including the patient-family, should achieve leadership when their contribution is relevant in managing task interdependence during transition. Shared leadership fosters coordinated actions to enable functioning as an integrated team-of-teams. This article illustrates how shared leadership can make a difference to coordinate interfaces and pathways, from therapy with curative intent to the follow-up and management of survivors of breast cancer. The detailed case is elaborated as a clinical vignette. It can be used by care providers and researchers to consider the need for new models of care for survivors of cancer by addressing the following questions. Who accepts shared leadership, how, with whom, and under what conditions? What is the evidence that supports the answers to these questions? The detailed case is also valuable for medical and allied health professional education.

Road kills of the endemic snake Perrotet’s Shieldtail Plectrurus perrotetii, Dumeril, 1851 (Reptilia: Squamata: Uropeltidae) in Nilgiris, Tamil Nadu, India

Twenty seven road killed specimens of Plectrurus perrotetii were recorded in Emerald and its surrounding areas in the Nilgiris. Among the road kills, fourteen of them were females, seven were males and six are juveniles. Among the road kill female specimens of this species, it was observed that seven were gravid with fully developed young. Three to six developing young ones were observed

Effect of vehicular traffic on wild animals in Sigur Plateau, Tamil Nadu, India

The construction of a road, directly and indirectly, impacts on the ecosystems where the road is built.  Highways passing through national reserves/wildlife sanctuaries have an adverse impact on wild animals.  The present survey was conducted to estimate the road kills on the state highways passing through the Nilgiri north territorial forest division (19km) and Mudumalai Tiger Reserve (15km) in Sigur Plateau, Tamil Nadu, India.  The road kills were monitored three times a month between July 2013 and December 2013 (six months) and a total of 176 road kills belonging to 30 species were recorded.  Reptiles were the most affected taxa (39%), followed by mammals (33%) and birds (21%).  Amphibians were least affected by vehicular traffic and comprised 7% of the total kills.  According to road stretch category, the overall road kill was N=135 in the forested area and N=41 in human habitations.  A total of 812 food materials were encounterd  612km with average of  1.32 food materials / km. Conservation and management implications are essential to prevent the local extinction of wildlife. 

Anticancer activity of koningic acid and semisynthetic derivatives

A screening program aimed at discovering novel anticancer agents based on natural products led to the selection of koningic acid (KA), known as a potent inhibitor of glycolysis. A method was set up to produce this fungal sesquiterpene lactone in large quantities by fermentation, thus allowing (i) an extensive analysis of its anticancer potential in vitro and in vivo and (ii) the semi-synthesis of analogues to delineate structure-activity relationships. KA was characterized as a potent, but non-selective cytotoxic agent, active under both normoxic and hypoxic conditions and inactive in the A549 lung cancer xenograft model. According to our SAR, the acidic group could be replaced to keep bioactivity but an intact epoxide is essential.

Dichapetalins from Dichapetalum species and their cytotoxic properties

Six dichapetalins named dichapetalins N-S were isolated from Dichapetalum mombuttense, Dichapetalum zenkeri and Dichapetalum leucosia. They were accompanied in the same plants by the known dichapetalins A, B, C, I, L and M. The structures of the compounds were elucidated by 1D and 2D NMR experiments and mass spectrometry. They all possessed the dammarane skeleton substituted at position C-3 by a C6-C2 unit forming a 2-phenylpyran moiety. All contained a lactone ring in the side chain except dichapetalins O, Q and R, in which this ring was replaced by a lactol. Dichapetalin Q and R were also the first dichapetalins bearing a tertiary methyl and a double bond instead of the cyclopropane of the dammaranes. All these compounds were assayed against cancer cell lines HCT116 and WM 266-4 and displayed cytotoxic and anti-proliferative activities in the 10(-6) to 10(-8)M range.

Identification of chiral alkenyl- and alkynylcarbinols as pharmacophores for potent cytotoxicity

Illumination by acetylene: Systematic structural variations in a series of archetypal acetylenic lipids derived from the naturally occurring (S,E)-icos-4-en-1-yn-3-ol allowed the discovery of a series of 3R-like 1,4-di-unsaturated carbinol units with a significant and systematic enantiomeric effect on cytotoxicity.

Living with the BRCA1 and BRCA2 genetic mutation: learning how to adapt to a virtual chronic illness

The objective of this study was to understand how women living with the BRCA1 and BRCA2 genetic mutation adapt to this life transition and to identify the main adaptive tasks. A qualitative inquiry inspired by grounded theory revealed that participants cognitively appraised their test result in the same manner as women who have been diagnosed with breast cancer. Consequently, participants had to adapt to a condition that they perceived as a chronic illness. The following three main tasks were identified: Physical Task: Attempting to Limit the Impact of the Test Result, Psychological Task: Living with Uncertainty, and Social Task: Finding Effective Support. In conclusion, although these women live with the possibility of developing breast cancer, their experiences mirror those of individuals living with a chronic illness, and they must therefore adapt accordingly in a physical, psychological, and social manner.

Individual predictions based on nonlinear mixed modeling: application to prenatal twin growth

The assessment of growth during fetal life and childhood commonly relies upon cross'sectional reference ranges or centiles. However, individual sequential predictions may help the timewise assessment of a growth process. In twin pregnancies for example, which are at risk of growth restriction, such predictions may improve the detection of abnormal trajectories. In this article, we present a simple forecasting method, assuming that a given normal individual behaves in the same way as a reference population. We consider, as a prediction in a given individual, the forecast of a future observation conditional to any previous observation and a set of population parameters obtained by nonlinear mixed modeling in a reference population. We suggest an estimator for this prediction without resorting to linear approximation and show that it enjoys interesting asymptotics when the amount of observations increases over time. We use two independent real datasets of twin pregnancies with normal growth and outcome to illustrate the application of such predictions in prenatal growth. We consider the first dataset as a reference dataset and model it using a two'level nonlinear model. We perform illustration and validation of predictions on the second dataset.

Living with the BRCA genetic mutation: an uncertain conclusion to an unending process

Women carrying a BRCA1 or BRCA2 genetic mutation have an up to 80% lifetime risk of developing breast cancer. It is especially important to understand the experiences of these women, as their lives are permeated with the threat of cancer. This qualitative study examined the experiences of six young women of reproductive age (age < 45 years) who were identified as carriers. The analysis of the semi-structured interviews inspired by grounded theory methodology, showed that participants experienced the same type of uncertainty demonstrated by women who have already been diagnosed with breast cancer.

Density estimation of a biomedical variable subject to measurement error using an auxiliary set of replicate observations

Correcting for measurement error when estimating the density of a routinely collected biomedical variable is an important issue when describing reference values for both healthy and pathological states. The present work addresses the problem of estimating the density of a biomedical variable observed with measurement error without any a priori knowledge on the error density. Assuming the availability of a sample of replicate observations, either internal or external, which is generally easily obtained in clinical settings, we propose an estimator based on the non-parametric deconvolution theory with an adaptive procedure for cutoff selection, the replicates being used for an estimation of the error density. We illustrate this approach in two applicative examples: (i) the systolic blood pressure distribution density, using the Framingham Study data set, and (ii) the distribution of the timing of onset of pregnancy within the female cycle, using ultrasound measurements in the first trimester of pregnancy.

Implementation of an integrated cancer care network

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Background: In 1998, the province of Quebec adopted its cancer control program (CP). Its goal was to establish a hierarchical and integrated cancer network of interdisciplinary teams. In 2004, a team evaluation process was initiated by the Direction de la lutte contre le cancer (ministry of health) to help implement this program. Methods: The evaluation consisted of completion of a matrix by the requesting team, a visit by a multidisciplinary group of experts and a report card. Three levels of expertise were assessed: core (all), regional (regional hospitals), and supraregional (tumor specific/complex situations). The matrix was based on the fundamental orientations of the CP, thus setting the framework for patient centered care. The conformity indicators were mainly structural and process oriented. In order to be evaluated for the subsequent mandates, teams had to conform to the core mandate. Those who did not succeed had one year to reapply. Mandates are for 4 years. Results: Teams were able to comply with most of the elements of the evaluation matrix. Sessions for clarification and coaching about this new interdisciplinary approach were necessary and helpful. A total of 153 visits were done:70 for core, 8 for regional and 75 for supraregional mandates respectively. Major health institutions such as university hospitals applied for multiple supraregional team designation. In all, 130 teams had their designation confirmed. This process highlighted some common weaknesses such as the lack of use of data for quality control. Conclusions: Acceptance of this hierarchical cancer care model was facilitated by the fact that it was in line with the integrated health care network of Quebec. The evaluation process has had an impact on the way cancer care is delivered in Quebec. This initial phase has helped implement an interdisciplinary patient centered model of care in line with the CP. Participation of different experts has also helped foster knowledge transfer and appropriation of the process. Impact on patient care and satisfaction remains to be assessed. An initial patient's questionnaire has been completed in 2008 and will serve as a control to future surveys.

No significant financial relationships to disclose.

Optimization of a homogeneous assay for kinase inhibitors in plant extracts

To identify natural and original kinase inhibitors from plant extracts, we have developed and compared a heterogeneous enzyme-linked immunosorbent assay (ELISA) and a homogeneous time-resolved fluorescence (HTRF, Cisbio International, Bagnols/Cèze, France) assay. Kinase affinity for the ATP substrate was determined in both assays, and the same [ATP]/ATP Km ratio was used in each case to enable the identification of ATP competitive and noncompetitive inhibitors. Assays were then used to screen the same collection of chemical compounds and plant extracts. The intra-assay correlation analysis of each technology showed a very good screening precision in HTRF and an acceptable one in ELISA. When the two methods were compared, a poor correlation was obtained with a higher hit rate in the ELISA. We then performed a detailed study of the ELISA hits and showed that they also presented a strong antioxidant activity, associated with high adsorption into microplate wells, which interfered with the horseradish peroxidase-based detection system. These hits were then flagged as false-positives. We also showed that many plant extracts presented this kind of activity and that this interference could explain the lack of correlation between the assays. These findings suggest that assay design should be carefully adapted to the substances to be screened and that interferences should be extensively considered before any assay development process and comparison studies. In spite of a few interferences, our results showed that a homogeneous-phase assay like the HTRF assay could be more efficiently used for plant extract screening than a heterogeneous-phase assay like ELISA.

High-Throughput Bioluminescence Screening of Ubiquitin-Proteasome Pathway Inhibitors from Chemical and Natural Sources

To discover original inhibitors of the ubiquitin-proteasome pathway, the authors have developed a cell-based bioluminescent assay and used it to screen collections of plant extracts and chemical compounds. They first established a DLD-1 human colon cancer cell line that stably expresses a 4Ubiquitin-Luciferase (4Ub-Luc) reporter protein, efficiently targeted to the ubiquitinproteasome degradation pathway. The assay was then adapted to 96- and 384-well plate formats and calibrated with reference proteasome inhibitors. Assay robustness was carefully assessed, particularly cell toxicity, and the statistical Ź factor value was calculated to 0.83, demonstrating a good performance level of the assay. A total of 18,239 molecules and 15,744 plant extracts and fractions thereof were screened for their capacity to increase the luciferase activity in DLD-1 4Ub-Luc cells, and 21 molecules and 66 extracts inhibiting the ubiquitin-proteasome pathway were identified. The fractionation of an active methanol extract of Physalis angulata L. aerial parts was performed to isolate 2 secosteroids known as physalin B and C. In a cell-based Western blot assay, the ubiquitinated protein accumulation was confirmed after a physalin treatment confirming the accuracy of the screening process. The method reported here thus provides a robust approach to identify novel ubiquitin-proteasome pathway inhibitors in large collections of chemical compounds and natural products.

Optometrist referrals for cataract and 'Action on Cataracts' guidelines: are optometrists following them and are they effective?

PURPOSE

To assess the information included in optometrist referrals for cataract to the Hospital Eye Service with reference to the recommendations made by the Department of Health in "Action on Cataracts" and the resultant surgical listing rates.

METHODS

We prospectively collected and analysed the information included in three different types of optometrist referrals for cataract over 8 weeks. Referrals containing "full information" as recommended in "Action on Cataracts" confirmed cataract as the cause of visual loss with a detrimental effect on the patient's lifestyle, and a willingness for surgery. The referral outcomes were assessed in terms of listing rate and the reasons for not listing, for each type of referral form.

RESULTS

A total of 412 referrals were analysed. Of these, 50% (208) were "conventional" referrals via the general practitioner (GP) [39% (n = 162) using the General Ophthalmic Services (GOS) 18 referral form and 11% (n = 46) an optometrist's custom letter]; 35% (n = 143) were direct referrals and 15% (n = 61) were GP referrals with no optometrist information (these results were excluded from further analysis). The listing rates for optometric referrals were 78% (n = 272) overall, 83% (n = 119) for direct and 74% (n = 153) for conventional referrals. "Full information" was included in 17% (n = 8) of letter referrals and 10% (n = 16) of GOS 18 referrals. The listing rates were 83% for referrals with full information and 73% for referrals specifying only that cataracts were the cause of visual loss. The listing rates for referrals with partial information were 78% for "cataract" plus "effect on lifestyle" and 67% for "cataract" plus "willingness for surgery". The most common reason for not listing a patient for surgery was "no effect on lifestyle", accounting for 42% (n = 32).

CONCLUSION

We recommend that all referrals for cataract should confirm a detrimental effect on lifestyle and the patient's willingness for surgery, in addition to confirming cataract as the main cause of visual loss.

Transformation-associated recombination (TAR) cloning of tumor-inducing Xmrk2 gene from Xiphophorus maculatus

We modified the TAR methodology of YAC clone construction for application to fish genomic DNA isolated from Xiphophorus maculatus. YAC libraries were developed using the XIR1 repeat sequence as the recombinational hook. Construction of these libraries demonstrates that Xiphophorus DNA sequences can function as hooks in the yeast recombination system and that X. maculatus genomic DNA contains sequences that provide origin of replication function in yeast. By screening a subset of Xiphophorus YAC clones, we isolated a clone harboring the Xmrk2 locus that is associated with spontaneous and induced melanomagenesis. Modifications of the TAR technique allowed the targeted cloning of specific genes from genomic regions ranging in size from cDNAs to several hundred kilobases. Specific genomic regions can be isolated in a directional manner from fixed map locations to saturate these areas with physical markers. We discuss the applications of these and other yeast recombinational processes to fish genetics.

Anti-sickling, analgesic and anti-inflammatory properties of 3,5-dimethoxy-4-hydroxy benzoic acid and 2,3,4-trihydroxyacetophenone

Effects of 3,5-dimethoxy-4-hydroxybenzoic acid and 2,3,4-trihydroxyacetophenone were studied on haemoglobin S (Hb S) polymerisation, analgesia and inflammation using Hb S solution, rats and mice. UV spectrophotometric procedure was used to monitor the polymerization of the Hb S. Acetic acid induced writhing in mice and egg albumin induced rat paw edema procedures were used to evaluate analgesic and anti-inflammatory activities of the compounds respectively. The results indicate that both drugs inhibit the process of polymerization significantly, possibly by direct action on the Hb S molecules. The drugs inhibited acetic acid induced pain and decreased egg albumin induced oedema. It is concluded that 3,5-dimethoxy-4-hydroxybenzoic acid and 2,3,4-trihydroxyacetophenone may have some value in the management of sickle cell disease.

Effect of somatostatin on electrogenic ion transport in the duodenum and colon of the mouse, Mus domesticus

In this study, we have used the mouse intestine and the Ussing short circuit technique to compare the effects and mechanism of action of somatostatin (SST, 0.1 microM) on cAMP- and Ca(2+)-mediated ion secretion in the duodenum and colon of the Swiss-Webster mouse. The cAMP-dependent secretagogues, prostaglandin E(2) (1 microM) and dibutyryl-cAMP (150 microM) increased short circuit current (I(sc)) in both regions, but only the colonic response was inhibited by SST. This inhibition was independent of enteric nerves, suggesting a direct action on the epithelial cells. The Ca(2+)-dependent secretagogue carbachol (10 microM) stimulated a transient increase in I(sc) in both intestinal segments. In the duodenum, SST partially inhibited this increase in I(sc) and both the responses to carbachol and SST were independent of enteric nerves. In the colon, while SST inhibited the carbachol induced increase in I(sc), pre-treatment with tetrodotoxin (750 nM) profoundly inhibited the carbachol induced increase in I(sc), thus markedly reducing the inhibitory effect of SST. This indicates an involvement of the enteric nervous system in the response to carbachol and the action of SST in the colon. These data indicate marked regional differences within the mouse intestine of the effects of SST on ion secretion and demonstrate different mechanisms of action of SST in the duodenum and colon.

Evaluation of Nigerian traditional medicine: effects of Gakani, a herbal anti-asthmatic drug

The anti-asthmatic potential of Gakani, a popular herbal drug in Nigeria was investigated. The LD50 values of the freeze-dried aqueous extract in mice and rats were 20.9 +/- 2.4 mg/kg and 18.6 +/- 4 mg/kg, respectively. The extract unsurmountably blocked the effects of histamine and isoprenaline on the guinea pig tracheaL chain. It produced initial dose-related contractions of the isolated guinea pig ileum and rat stomach strip, which was followed by persistent autoinhibition and inhibition of histamine- and 5-hydroxytryptamine (5-HT)-induced responses of the two preparations, respectively. The extract had good anti-inflammatory effect in rats, causing a dose-related inhibition of the increase in the paw circumference (acute inflammation) induced by subplantar injection of fresh egg albumin. These results highlight the anti-asthmatic and toxic potential of this preparation and the need for a systemic approach in the study of traditional medicines.

A novel rapid hybridization technique: paper chromatography hybridization assay (PACHA)

A new DNA hybridization technique, based on chromatographic migration of DNA on a nitrocellulose strip passing through an immobilized probe area, is described. The new paper chromatography hybridization assay (PACHA) is faster and simpler to use than the conventional dot hybridization assay. In this assay, an aliquot of biotinylated, PCR-amplified target DNA is applied to one end of a nitrocellulose strip. The DNA migrates to the opposite end of the strip by capillary forces and hybridizes to a specific DNA probe immobilized in a reaction zone (RZ), located in the middle of the strip. Unhybridized DNA migrates away from the RZ. The biotinylated hybrid is visualized by a color reaction employing a streptavidin-alkaline phosphatase (SA-AP) conjugate and a specific chromogenic substrate. The new PACHA technique allows for detection of as little as 1-5 pg of specific human papilloma virus 16 (HPV16) DNA in 25 min of hybridization. In this system, the hybridization efficiency is controlled by the flow velocity of the hybridization solution (HS) and by the volume of the amplified labeled DNA migrating across the immobilized probe. Glycerol (30%) or polyvinyl pyrrolidone (PVP) (1%) reduces the flow rate by a factor of 2.5-3 and increases the sensitivity of the assay by a factor of 5.2 for glycerol and 2.6 for PVP. This novel method ensures efficient hybridization to multiple probes and appears to be superior to currently available solid-phase hybridization techniques.

Binocular interaction and disparity coding in area 19 of visual cortex in normal and split-chiasm cats

Binocular disparity, resulting from the projection of a three-dimensional object on the two spatially separated retinae, constitutes one of the principal cues for stereoscopic perception. The binocularity of cells in one hemisphere stems from two sources: (1) the ganglion cells in the homonymous temporal and nasal hemiretinae and (2) the contralateral hemisphere via the corpus callosum (CC). The objectives of this study were, on one hand, to determine whether disparity-sensitive cells are present in a "higher order" area, namely area 19 of the visual cortex, of the cat and, on the other hand, to ascertain whether the CC contributes to the formation of these cells. As in areas 17-18, two types of disparity-sensitive neurons were found: one type, showing maximal interactive effects around zero disparity, responded with strong excitation or inhibition when the stimuli presented independently to the two eyes were in register. These neurons are presumed to signal stimuli situated about the fixation plane. The other type, also made up of two subtypes of opposed valencies, gave maximum responses at one set of disparities and inhibitory responses to the other set. These are presumed to signal stimuli situated in front of or behind the fixation plane. Unlike areas 17-18, however, disparity-sensitive cells in area 19 of the normal cat were less finely tuned and their proportion was lower. In the split-chiasm animal, very few cells were sensitive to disparity. These results, when coupled with behavioral data obtained with destriate animals, indicate that (1) area 19 is probably less involved in the analysis of disparity information than area 17, (2) the disparity-sensitive neurons that are sensitive to disparity are not involved in the resolution of very fine three-dimensional spatial detail, and (3) the CC only determines a limited number of these cells in the absence of normal binocular input.

Binocular interaction and disparity coding at the 17-18 border: contribution of the corpus callosum

Binocular disparity, resulting from the projection of a three-dimensional object on the two spatially separated retinae, constitutes one of the fundamental cues for stereoscopic perception. The binocularity of cells in one hemisphere stems from two sources: i) from the ipsilateral ganglion cells in the temporal retina which converge with inputs coming from the contralateral nasal retina; the latter axons cross at the chiasma; ii) from inputs originating in the opposite hemisphere which cross in the corpus callosum. The objective of this study was to demonstrate that interactions from both types of inputs can result in the formation of disparity sensitive neurons and presumably that either type could mediate stereoperception based on disparity cues. Two types of disparity sensitive neurons were found in the normal cat: one type, showing maximal interactive effects around zero disparity responded with strong excitation or inhibition when the stimuli were in register. These neurons are presumed to signal stimuli situated about the fixation plane. The other type, also made up of two subtypes of opposed valencies, gave maximum responses at one set of disparities and inhibitory responses to the other set. These were presumed to signal stimuli situated in front of or behind the fixation plane. In the split-chiasm cat, whose cortical binocularity is presumably assured by converging ipsilateral and callosal inputs, three of the four subtypes of disparity sensitive neurons were found, the uncrossed disparity cells being absent in these animals. Moreover, stimulating each eye individually indicated that nearly 80% of the cells in normal and about 40% in split-chiasm cats were binocularly driven. However, both these figures underestimated the amount of binocular interaction in the callosal recipient zone, since stimulating both eyes simultaneously showed that a proportionately larger number of cells were binocularly driven. Disparity sensitive cells also varied as a function of ocular dominance, i.e., cells signaling the fixation plane tended to have balanced dominance whereas units preferring stimuli situated in front of or behind the fixation plane were dominated by the ipsilateral and contralateral eyes, respectively.