Evaluation expérimentale de stratégies de déploiement de gènes de résistance pour la gestion durable des nématodes à galles

Dans le cadre de projets soutenus par l'ANR Systerra et le GIS PICLeg (projets "Sysbiotel" et "Neoleg") menés en collaboration entre l'INRA PACA, l'IRD, l'APREL, la Chambre d'Agriculture du 06 et des entreprises privées de sélection de semences, plusieurs stratégies de déploiement de gènes de résistance ont été évaluées pendant 3 ans sur le terrain en conditions agronomiques pour mettre au point une gestion raisonnée des cultivars résistants permettant de gérer de manière durable les problèmes de nématodes à galles des racines. L'alternance des gènes de résistance dans la rotation et le "pyramiding" de gènes dans un même cultivar se sont révélés extrêmement efficaces pour supprimer l'émergence de populations virulentes et réduire les taux d'infestation du sol de plus de 80% en 3 ans. Un nouveau projet INRA "Gedunem", mis en place dans le cadre du Métaprogramme INRA SMaCH (Sustainable Management of Crop Health), vise maintenant à associer ces innovations variétales aux autres méthodes de lutte disponibles (gestion de l'interculture, plantes non hôtes, prophylaxie) afin de maintenir une pression parasitaire faible, tout en évaluant ces nouveaux systèmes de culture du point de vue agronomique et socio-économique

Kesan sitotoksik dan aktiviti anti-mrsa ekstrak metanol phyllanthus gracilipes dan phyllanthus columnaris

Satu kajian telah dijalankan untuk menguji kesan sitotoksik dan aktiviti antibakteria ekstrak metanol dari bahagian berbeza tumbuhan Phyllanthus gracilipes dan P. columnaris. Pengekstrakan dilakukan pada suhu bilik dan menggunakan alat-radas Soxhlet untuk menghasilkan 22 ekstrak. Ujian fitokimia ke atas ekstrak Soxhlet menunjukkan kehadiran saponin dalam semua ekstrak manakala steroid terdapat dalam ekstrak semua bahagian P. gracilipes dan 3 daripada ekstrak P. columnaris. Ujian sitotoksik ke atas kultur sel Vero menunjukkan hanya empat ekstrak yang sitotoksik dengan nilai LC50 di bawah 20 μg/mL iaitu ekstrak suhu bilik kulit-batang P. gracilipes, ekstrak Soxhlet kayu-batang dan daun P. gracilipes serta ekstrak suhu bilik kayu-akar P. columnaris. Ekstrak suhu bilik dan Soxhlet kayu-batang P. gracilipes serta semua ekstrak suhu bilik P. columnaris merencat pertumbuhan 13 pencilan Staphylococcus aureus Rintang-Metisillin (MRSA) yang diuji

Acuminatol and other antioxidative resveratrol oligomers from the stem bark of Shorea acuminata

A new resveratrol dimer, acuminatol (1), was isolated along with five known compounds from the acetone extract of the stem bark of Shorea acuminata. Their structures and stereochemistry were determined by spectroscopic methods, which included the extensive use of 2D NMR techniques. All isolated compounds were evaluated for their antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (RSA) and the ß-carotene-linoleic acid (BCLA) assays, and compared with those of the standards of ascorbic acid (AscA) and butylated hydroxytoluene (BHT). All compounds tested exhibited good to moderate antioxidant activity in the DPPH assay (IC50s 0.84 to 10.06 mM) and displayed strong inhibition of ß-carotene oxidation (IC50s 0.10 to 0.22 mM). The isolated compounds were evaluated on the Vero cell line and were found to be non-cytotoxic with LC50 values between 161 to 830 µM

Clinical characteristics, management, maternal and neonatal outcome among seven severe and critically ill pregnant women with COVID-19 pneumonia

Pneumonia caused by the Novel coronavirus disease 2019 (COVID-19) is a highly infectious disease and the ongoing outbreak has been declared as a Pandemic by the World health organization. Pneumonia is a serious disease in pregnancy and requires prompt attention. Viral pneumonia has higher morbidity and mortality compared to bacterial pneumonia in pregnancy. All efforts are well exerted to understand the newly emerged disease features but still some areas are gray. The treatment is primarily supportive with antivirals, steroids, anticoagulation and antibiotics for secondary bacterial infection. Severe cases require intensive care monitoring with oxygen support, mechanical ventilation. Investigational therapies include convalescent plasma, cytokine release inhibitors and other immunomodulatory agents like interferons. The mortality appears driven by the presence of severe Adult Respiratory Syndrome (ARDS) and organs failure. COVID pandemic is a challenging and stressful socio-economic situation with widespread fear of infection, disease and death. In the specialty of obstetrics and gynecology, studies are being conducted to ascertain the manifestation of disease in pregnant women and the fetal outcome. The aim of our case series is to describe the demographics, clinical characteristics, laboratory and radiological findings, feto- maternal outcome of severe and critical COVID pneumonia in pregnant women in Latifa Hospital

Pyramiding, alternating or mixing : comparative performances of deployment strategies of nematode resistance genes to promote plant resistance efficiency and durability

Background: Resistant cultivars are key elements for pathogen control and pesticide reduction, but their repeated use may lead to the emergence of virulent pathogen populations, able to overcome the resistance. Increased research efforts, mainly based on theoretical studies, explore spatio-temporal deployment strategies of resistance genes in order to maximize their durability. We evaluated experimentally three of these strategies to control root-knot nematodes: cultivar mixtures, alternating and pyramiding resistance genes, under controlled and field conditions over a 3-years period, assessing the efficiency and the durability of resistance in a protected crop rotation system with pepper as summer crop and lettuce as winter crop. Results: The choice of the resistance gene and the genetic background in which it is introgressed, affected the frequency of resistance breakdown. The pyramiding of two different resistance genes in one genotype suppressed the emergence of virulent isolates. Alternating different resistance genes in rotation was also efficient to decrease virulent populations in fields due to the specificity of the virulence and the trapping effect of resistant plants. Mixing resistant cultivars together appeared as a less efficient strategy to control nematodes. Conclusions: This work provides experimental evidence that, in a cropping system with seasonal sequences of vegetable species, pyramiding or alternating resistance genes benefit yields in the long-term by increasing the durability of resistant cultivars and improving the long-term control of a soil-borne pest. To our knowledge, this result is the first one obtained for a plant-nematode interaction, which helps demonstrate the general applicability of such strategies for breeding and sustainable management of resistant cultivars against pathogens

Maternal sepsis in intensive care unit at Omdurman New Hospital-Tertiary Obstetric Facility, Khartoum-Sudan

Introduction: Sever sepsis and septic shock contributes to maternal morbidity and mortality. The etiology of sever sepsis and septic shock during pregnancy and postpartum result from obstetric related or non-obstetric related conditions. Objectives: It aimed to determine rate, characters, morbidity and mortality of septic obstetric cases at Omdurman New Hospital. Methods: It was a descriptive, prospective, analytic, cross-sectional hospital based total coverage study; conducted at Omdurman New Hospital (ONH), Khartoum-Sudan. Results: Sever sepsis and septic shock rate 1.16 (13/1124 = 1.16%) of hospital pregnancy complication admission. Hyperthermia, Tachycardia and hypotension are the main presenting clinical findings and uterine infection is the main focus of sepsis. The mean average Intensive Care Unit (ICU) stay is 6.3-day. Organs dysfunctions are the main morbidity and mortality is reported in five cases. Conclusion: Sever sepsis and septic shock contributes in maternal morbidity and mortality. Safe obstetric care prevents maternal sepsis and improves the outcome. Management of sever sepsis and septic shock remains a challenge in obstetric medicine