Parameter Estimation in a PDE Model for the Spatial Spread of Cocoa Black Pod Disease.

In this paper, we develop an epidemiological model with both environmental (primary infection from the environmental spores reservoir) and direct transmission (secondary infection from an infected host to a susceptible pod). This model simulates the spatiotemporal evolution of cocoa black pod disease caused by Phytophthora megakarya. Since reliable parameter estimation is a central issue for modeling realistic biological systems, we used a mechanistic-statistical approach to estimate model parameters from real observations of a specific cocoa plot. In addition, to refine numerical simulations of the pathosystem, data describing the shade intensity all over the plot were exploited and led to increased model predictions accuracy and also highlighted a higher number of infected pods located in areas of the plot with higher shading intensity. Recommendations in terms of promoting cocoa farming in systems with low shading intensity may be evident if these results are confirmed. Our results also highlight the importance of the environmental spore reservoir in black pod disease dynamics.

[Lactobacillus delbrueckii: probable agent of urinary tract infections in very old women]. / Lactobacillus delbrueckii : probable cause d'infections urinaires chez la femme très âgée.

Lactobacillus urinary tract infection (UTI) seems exceptionally reported. Nevertheless, with the introduction of a chromogenic medium UriSelect 4, eight cases of UTI in old women (mean of 81.2 years) mediated by Lactobacillus delbrueckii identified by DNA sequencing were reported between 2007 and 2009.

Evaluation of Senegalese plants used in malaria treatment: focus on Chrozophora senegalensis.

An ethnobotanical study was conducted in the Dakar area of Senegal to investigate the species used in the treatment of malaria. Seven plants are principally used: Cissampelos mucronata, Maytenus senegalensis, Terminalia macroptera, Bidens engleri, Ceratotheca sesamoides, Chrozophora senegalensis and Mitracarpus scaber. From a bibliographic study, it had been shown that the Cissampelos mucronata, Maytenus senegalensis and Terminalia macroptera have already been studied by several authors, and so only Bidens engleri, Ceratotheca sesamoides, Chrozophora senegalensis and Mitracarpus scaber were evaluated in the present study. For each plant, extracts were prepared with different solvents and tested in vitro on two chloroquine-resistant Plasmodium falciparum strains. Crude extracts from the leaves and the stems of Chrozophora senegalensis showed the best in vitro results. The IC(50) value of an aqueous extract of Chrozophora senegalensis was 1.6 microg/ml without cytotoxicity. The in vivo antiplasmodial activity of Chrozophora extracts was determined by both the oral and the intraperitoneal ways. The stages of Plasmodium cycle targeted by Chrozophora were then studied in vitro. These results could justify the traditional use of this plant in malaria treatment.

Urinary and genital infections in patients with diabetes: How to diagnose and how to treat.

Diabetes is a predisposing factor for urinary tract and genital infections in both women and men. Sodium-glucose cotransporter-2 (SGLT2) inhibitors constitute a novel therapeutic class indicated for type 2 diabetes (T2D) patients, and are already on the market in a few countries in Europe. They decrease glycaemia mainly by enhancing glucose excretion in urine by reducing renal glucose reabsorption via the action of SGLT2 in the kidneys. In general, they are well tolerated, but their mode of action results in specific side effects as well as an increased risk of genital (vulvovaginitis and balanitis) and urinary tract infections, for which T2D patients are already at high risk, reported within the first 6 months of treatment. Usually these infectious events are successfully treated with standard therapies, but diabetologists are not accustomed to dealing with them. The aim of this review is to describe the different types of lower urinary tract and genital infections, and the treatment strategies currently available for patients with diabetes.

Subject-Specific Effect of Metallic Body Accessories on Path Loss of Dynamic on-Body Propagation Channels.

This paper presents the investigation of path loss variation for subject-specific on-body radio propagation channels, considering the effect of metallic spectacles and loop like metallic accessories. Adding metallic items may affect the operability of Body Centric Wireless Communications (BCWC). Measurements were carried out in an RF-shielded room lined with microwave absorbing sheets for strategically placed bodyworn antennas covering the upper front torso and the lower limbs. The path loss of the on-body radio channel was characterized explicitly taking into account the body size of the subjects. For metallic loop-like accessories, the results indicate that for underweight subjects, there was a slightly higher influence, up to 2%, compared to normal and overweight subjects. Our findings indicate that a noticeable effect exists on on-body channels for dynamic movements where the metallic watch acts as a local scatterer that affects the non-line-of-sight (NLOS) signal path between transmitter and receiver for underweight subjects in comparison to normal and overweight subjects. The path loss decreases when the receiving terminal was positioned very close to the metallic item. If a loop-like metallic accessory is not appropriately considered when designing the radio channel on a subject, the reliability of the body-centric wireless system may degrade.

Samvisterin, a new natural antiplasmodial betulin derivative from Uapaca paludosa (Euphorbiaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Uapaca paludosa is used in African traditional medicine for the treatment of malaria. MATERIALS AND METHODS: A bioguided fractionation of U. paludosa trunk bark extracts was performed on the basis of their antiplasmodial activity against Plasmodium falciparum. RESULTS: A new natural betulin derivative named samvisterin (2) was isolated. In addition, 12 already known compounds were isolated from U. paludosa and tested against P. falciparum: squalene (1); lupeol (3), betulonic acid methyl ester (4), ß-sitosterol (5), stigmasterol (6), betulin (7), betulinic acid (8), pentadecanoic acid (9), palmitic acid (10), margaric acid (11), stearic acid (12), methyl palmitate (13). With the exception of betulinic acid, all were isolated for the first time from U. paludosa. Their chemical structures were established on the basis of spectroscopic analysis. The antiplasmodial activity of compounds 1-8 was confirmed on the chloroquine-resistant strain of P. falciparum, FcM29-Cameroon, with IC50 values ranging from 0.7µg/ml (for 1) to 30µg/mL (for 3). The cytotoxicity of the fractions and isolated compounds was also determined on KB and Vero cell lines in order to determine the cytotoxicity/activity ratio of each one. CONCLUSIONS: The results obtained with samvisterin (2) show that this new compound is the most promising of the series, with a weak cytotoxicity leading to the best selectivity index values.

Multivariate genetic determinants of EEG oscillations in schizophrenia and psychotic bipolar disorder from the BSNIP study.

Schizophrenia (SZ) and psychotic bipolar disorder (PBP) are disabling psychiatric illnesses with complex and unclear etiologies. Electroencephalogram (EEG) oscillatory abnormalities in SZ and PBP probands are heritable and expressed in their relatives, but the neurobiology and genetic factors mediating these abnormalities in the psychosis dimension of either disorder are less explored. We examined the polygenic architecture of eyes-open resting state EEG frequency activity (intrinsic frequency) from 64 channels in 105 SZ, 145 PBP probands and 56 healthy controls (HCs) from the multisite BSNIP (Bipolar-Schizophrenia Network on Intermediate Phenotypes) study. One million single-nucleotide polymorphisms (SNPs) were derived from DNA. We assessed eight data-driven EEG frequency activity derived from group-independent component analysis (ICA) in conjunction with a reduced subset of 10,422 SNPs through novel multivariate association using parallel ICA (para-ICA). Genes contributing to the association were examined collectively using pathway analysis tools. Para-ICA extracted five frequency and nine SNP components, of which theta and delta activities were significantly correlated with two different gene components, comprising genes participating extensively in brain development, neurogenesis and synaptogenesis. Delta and theta abnormality was present in both SZ and PBP, while theta differed between the two disorders. Theta abnormalities were also mediated by gene clusters involved in glutamic acid pathways, cadherin and synaptic contact-based cell adhesion processes. Our data suggest plausible multifactorial genetic networks, including novel and several previously identified (DISC1) candidate risk genes, mediating low frequency delta and theta abnormalities in psychoses. The gene clusters were enriched for biological properties affecting neural circuitry and involved in brain function and/or development.

Comparison of real and placebo acupuncture in histamine-induced asthma. A double-blind crossover study.

A double-blind crossover study of the effects of real and placebo acupuncture on bronchial reactivity to histamine was carried out on 16 patients with moderately severe asthma. Treatment with real or placebo acupuncture failed to modulate the bronchial hyperreactivity to histamine. These results suggest that a single treatment with acupuncture is unlikely to provide improvement in the management of acute bronchial asthma.

Iron deficiency and risk factors for lower iron stores in 6-24-month-old New Zealanders.

OBJECTIVES: To determine the prevalence of biochemical iron deficiency and identify factors associated with ferritin levels among 6-24-month-old urban South Island New Zealand children. DESIGN: Cross-sectional survey conducted from May 1998 to March 1999. SETTING: The cities of Christchurch, Dunedin and Invercargill. SUBJECTS: A total of 323 randomly selected 6-24-month-old children participated (response rate 61%) of which 263 provided a blood sample. METHODS: A complete blood cell count, zinc protoporphyrin, serum ferritin and C-reactive protein were measured on nonfasting venipuncture blood samples, 3-day weighed food records and general questionnaire data were collected. RESULTS: Among children with C-reactive protein<10 mg/l (n=231), 4.3% had iron deficiency anaemia, 5.6% had iron deficiency without anaemia, and 18.6% had depleted iron stores, when a ferritin cutoff of < or =12 g/l was used. Age (negative), sex (girls>boys), ethnicity (Caucasian>non-Caucasian), weight-for-age percentiles (negative) and birth weight (positive) were associated with ferritin after adjusting for infection and socioeconomic status. When current consumption of iron fortified formula and >500 ml of cows' milk per day were included, these were associated with a 22% increase and 25% decrease in ferritin, respectively (R2=0.28). CONCLUSIONS: The presence of suboptimal iron status (29%) among young New Zealand children is cause for concern, even though severe iron deficiency is rare, because children with marginal iron status are at risk of developing severe iron deficiency if exposed to a physiological challenge.

Organ procurement in Singapore.

Kidney transplantation, an accepted therapeutic intervention for patients with end stage kidney failure, was pioneered in Singapore on 8 July 1970 by the University Departments of Surgery and Medicine, University of Singapore. Up to 1987, an average of 4.7 cadaveric kidney transplants were performed annually. The introduction of Sandimmune (cyclosporine) in 1985 significantly increased graft survival and consequently created a demand for more cadaveric kidneys for transplantation. The rate of cadaveric kidney transplants escalated to 31.3 kidney transplants annually for the period 1988 to 1990. This increase can be attributed both to the appointment of full time transplant coordinators beginning April 1986 and the implementation of the Human Organ Transplant Act in July 1987. The Human Organ Transplant Act accounted for more than half of all kidneys procured for transplantation (55/94) for the period 1988 to 1990.

An in vitro assessment of human fetal pancreatic islets of Langerhans in culture.

The human fetal pancreas is a potential source of islets for transplantation into insulin-dependent diabetic patients. In this study, 35 human fetal pancreas obtained from prostaglandin-induced abortions (12-26 weeks gestation), were placed in culture to determine their capacity to secrete insulin over 30 days. Culture media were sampled twice weekly for insulin and histology was performed serially. Of the 35 pancreases cultured, six were lost due to bacterial contamination, five discarded due to undetectable levels of insulin in culture, nine are still under study, whilst 15 pancreases have been cultured for one month, and insulin studies completed. Three patterns of insulin release were observed: (a) progressive decline (n = 6), indicating non-viable tissue at the onset; (b) delayed decline, indicating significant tissue damage before organ culture (n = 5); and (c) insulin production in vitro over 30 days (n = 4), with viable islets detected histologically. Factors such as gestational age and cold ischaemia time did not correlate with the pattern of insulin secretion observed. This was probably due to a more important variable, not easily assessed, of the period of intrauterine (warm) ischemia. These data suggest: (1) that a small number of fetal pancreases procured from prostaglandin-induced abortuses do yield islets which remain viable in culture over 30 days, and (2) the functional status of islets can be monitored in vivo by measuring insulin secretion, thereby providing a means of identifying tissue suitable for transplantation.

Proposal for a predictive model of erectile function after permanent (125)I prostate brachytherapy for localized prostate cancer.

To determine the risk factors for EDin men treated by prostate brachytherapy (PB) for localized prostate cancer and to propose a model to predict post-implant erectile function. Out of a series of 270 sexually active men treated by PB, 241 (89%) (mean age=66 years (range, 43-80)) accepted to participate in a mail-based study on erectile function. The risk factors for erectile dysfunction were determined by regression analysis and a predictive model was proposed. The performance of the model was determined in this population and subsequently verified in a population of 50 men treated by PB in another treatment center. The risk factors for ED after PB were age, the pre-implant IIEF score and prostate volume. In the studied population, the final model to predict a post-treatment IIEF-5 score, using these factors, had a sensitivity of 69% and a specificity of 68% associated to an area under the ROC curve (AUC) of 0.75. The same performance was obtained in another treatment center. Age, pre-implant IIEF-5 score and prostate volume may be used to predict post-implant erectile function in patients treated by PB.

Both plants Sebastiania chamaelea from Niger and Chrozophora senegalensis from Senegal used in African traditional medicine in malaria treatment share a same active principle.

ETHNOPHARMACOLOGICAL RELEVANCE: Based on ethnobotanical data obtained from Nigerien and Senegalese traditional healers, two Euphorbiaceae plants, Sebastiania chamaelea and Chrozophora senegalensis, traditionally used to treat malaria, were selected for further investigations. MATERIALS AND METHODS: Plant extracts were prepared with different solvents and tested both in vitro on several strains of Plasmodium falciparum, and in vivo to evaluate their antiplasmodial properties and isolate their active principles. RESULTS: With IC50 values around 6.5µg/ml and no significant cytotoxicity (>50µg/ml), the whole plant aqueous extract from S. chamaelea showed the best in vitro results. In vitro potentiation assays showed strong synergistic activity of S. chamaelea extract with the antiplasmodial drug chloroquine on the chloroquine-resistant P. falciparum strain W2-Indochina. In other respects, the aqueous crude extract of C. senegalensis leaves showed the most significant antiplasmodial activity in vitro (IC50 values less than 2µg/ml). We also demonstrated the prophylactic activity of C. senegalensis in vivo in a murine malaria model. Bioassay-guided fractionation of aqueous extracts of these plants enabled the isolation and identification of ellagic acid (EA, 1) as the main compound responsible for their antiplasmodial activity. Together with EA, other derivatives belonging to different chemical groups were isolated but showed moderate antimalarial activity: gallic acid (2), brevifolin carboxylic acid (3), protocatechuic acid (4), corillagin (5), rutin (6) and 3,4,8,9,10-pentahydroxy-dibenzo(b,d)pyran-6-one (7). The structures were determined by the usual spectroscopic methods and by comparison with published data. Furthermore, we report here the quantification of compound 1 (EA) by RP-HPLC in the dried extracts of these plants, reported for the first time in both these species, and possessing the highest in vitro antiplasmodial activity with IC50 values from 180 to 330nm. CONCLUSIONS: These in vitro and in vivo results support the traditional use in Africa of crude extracts of both S. chamaelea and C. senegalensis as an antimalarial treatment and prove the significant antiplasmodial property of EA.