A rare case of thyrotoxic periodic paralysis revealing Graves' disease in a young Malian.

Sporadic thyrotoxic periodic paralysis (TPP) is a rare muscle disorder that manifests with abrupt muscle weakness and hypokalemia associated with hyperthyroidism. It is mostly reported in the Asian population, and rare in Caucasians. Only few cases have been reported in people with black ancestry. Here, we report a rare case of thyrotoxic periodic paralysis revealing Graves' disease in a young Malian. A 17-year-old man was admitted in the Neurology clinic with rapid proximal tetraplegia that started after strenuous physical activities at the school. Clinical examination confirmed the proximal weakness. In addition, he had bilateral ptosis, exophthalmia, and horizontal ophthalmoplegia. Laboratory testing showed normal serum potassium and creatinine, low calcium and TSH levels. However, CK, FT4, thyroid stimulating hormone antibody, and acetylcholine receptor antibody levels were high. In addition, electrocardiogram was normal while thyroid Doppler-ultrasound showed heterogeneous, hypoechogenic, hypertrophic, and hyper vascularized gland. Patient had completely recovered his limb weakness within the following hours with symptomatic treatment. The clinical findings were consistent with Graves' disease, and he was put on Neomercazole. He did not present another episode of paralysis after 4-years of follow up. This is a first case of thyrotoxic periodic paralysis reported in Mali and one of the rare cases in sub-Saharan Africa. Despite its scarcity, all patients with acute weakness consecutive to effort, whether recurring or not, should be screened for TPP.

[Covid19 in a polypathological subject]. / Pneumopathie a covid19 chez un sujet polypathologique.

In December 2019, an outbreak of pneumonia due to the 2019 novel coronavirus, SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), broke out in Wuhan, Hubei, China. This betacoronavirus causes a sometimes severe respiratory pathology, named COVID-19 by the World Health Organization (WHO). The WHO declared COVID-19 as a pandemic in March 2020. It is Mrs. RM, 71 years old of French nationality who consults for dyspnea on exertion for 8 days associated with a dry cough, an intermittent fever with periods of spontaneous remissions, a chest pain accentuated by the efforts of cough, a physical asthenia, non-selective anorexia, diarrhea and vomiting. The physical examination found respiratory distress with 72% desaturation in ambient air, requiring oxygen-requisition with 96% oxygen saturation under 10 liters with no sign of respiratory struggle; crackling rales with 2 more predominant lung fields on the right, mucocutaneous jaundice, edema of the lower limbs. The management was intubation upon admission with mechanical ventilation, oral administration of hydroxychloroquine 200 mg due to 2 tablets morning and evening for 24 hours then 1 tablet morning and evening for 04 days, antibiotic therapy based on ceftriaxone 1g morning and evening was implemented, in the absence of bacteriological evidence. The course was unfavorable with a death with the absence of clinical improvement and a very precarious hematosis escaping any treatment alternative. CONCLUSION: Covid19 is a very serious virus with a poor prognosis in multiple pathological patients.

En décembre 2019, une épidémie de pneumonie due au nouveau coronavirus 2019, le SARS-CoV-2 (sévère acute respiratory syndrome coronavirus 2) a éclaté à Wuhan, Hubei, Chine. Ce bétacoronavirus provoque une pathologie respiratoire parfois sévère, nommée COVID-19 par l'organisation mondiale de la santé (OMS). L'OMS a déclaré en mars 2020, la COVID-19 comme une pandémie. Il s'agit de madame RM, 71 ans de nationalité française qui consulte pour dyspnée d'effort depuis 8 jours associée à une toux sèche, une fièvre intermittente avec des périodes de remissions spontanées, une douleur thoracique accentuée par les efforts de toux, une asthénie physique, une anorexie non sélective, des diarrhées et vomissements. L'examen physique retrouve une détresse respiratoire avec une désaturation à 72% en air ambiant, nécessitant une oxygeno-réquerance avec une saturation en oxygène à 96% sous 10 litres sans signe de lutte respiratoire ; des rales crépitants aux 2 champs pulmonaires plus prédominants à droite, un ictère cutanéomuqueux, des œdèmes des membres inférieurs. La prise en charge a été une intubation dès son admission avec ventilation mécanique, l'administration par la voie orale de l'hydroxychloroquine 200 mg en raison de 2 comprimés matin et soir pendant 24heures puis 1comprimé matin et soir pendant 04 jours, l'antibiothérapie à base de ceftriaxone 1g matin et soir a été mis en place, en l'absence de preuve bactériologique. L'évolution fut défavorable par un décès avec l'absence d'amélioration clinique et une hématose très précaire échappement à toute alternative thérapeutique. CONCLUSION: La covid19 est une virose très grave au pronostic sombre chez les patients poly- pathologiques.

Genetic variation and host-parasite specificity of Striga resistance and tolerance in rice: the need for predictive breeding.

The parasitic weeds Striga asiatica and Striga hermonthica cause devastating yield losses to upland rice in Africa. Little is known about genetic variation in host resistance and tolerance across rice genotypes, in relation to virulence differences across Striga species and ecotypes. Diverse rice genotypes were phenotyped for the above traits in S. asiatica- (Tanzania) and S. hermonthica-infested fields (Kenya and Uganda) and under controlled conditions. New rice genotypes with either ecotype-specific or broad-spectrum resistance were identified. Resistance identified in the field was confirmed under controlled conditions, providing evidence that resistance was largely genetically determined. Striga-resistant genotypes contributed to yield security under Striga-infested conditions, although grain yield was also determined by the genotype-specific yield potential and tolerance. Tolerance, the physiological mechanism mitigating Striga effects on host growth and physiology, was unrelated to resistance, implying that any combination of high, medium or low levels of these traits can be found across rice genotypes. Striga virulence varies across species and ecotypes. The extent of Striga-induced host damage results from the interaction between parasite virulence and genetically determined levels of host-plant resistance and tolerance. These novel findings support the need for predictive breeding strategies based on knowledge of host resistance and parasite virulence.

Do NERICA rice cultivars express resistance to Striga hermonthica (Del.) Benth. and Striga asiatica (L.) Kuntze under field conditions?

The parasitic weeds Striga asiatica and Striga hermonthica cause high yield losses in rain-fed upland rice in Africa. Two resistance classes (pre- and post-attachment) and several resistant genotypes have been identified among NERICA (New Rice for Africa) cultivars under laboratory conditions (in vitro) previously. However, little is known about expression of this resistance under field conditions. Here we investigated (1) whether resistance exhibited under controlled conditions would express under representative Striga-infested field conditions, and (2) whether NERICA cultivars would achieve relatively good grain yields under Striga-infested conditions. Twenty-five rice cultivars, including all 18 upland NERICA cultivars, were screened in S. asiatica-infested (in Tanzania) and S. hermonthica-infested (in Kenya) fields during two seasons. Additionally, a selection of cultivars was tested in vitro, in mini-rhizotron systems. For the first time, resistance observed under controlled conditions was confirmed in the field for NERICA-2, -5, -10 and -17 (against S. asiatica) and NERICA-1 to -5, -10, -12, -13 and -17 (against S. hermonthica). Despite high Striga-infestation levels, yields of around 1.8 t ha-1 were obtained with NERICA-1, -9 and -10 (in the S. asiatica-infested field) and around 1.4 t ha-1 with NERICA-3, -4, -8, -12 and -13 (in the S. hermonthica-infested field). In addition, potential levels of tolerance were identified in vitro, in NERICA-1, -17 and -9 (S. asiatica) and in NERICA-1, -17 and -10 (S. hermonthica). These findings are highly relevant to rice agronomists and breeders and molecular geneticists working on Striga resistance. In addition, cultivars combining broad-spectrum resistance with good grain yields in Striga-infested fields can be recommended to rice farmers in Striga-prone areas.

New Rice for Africa (NERICA) cultivars exhibit different levels of post-attachment resistance against the parasitic weeds Striga hermonthica and Striga asiatica.

Striga hermonthica and S. asiatica are root parasitic weeds that infect the major cereal crops of sub-Saharan Africa causing severe losses in yield. The interspecific upland NEw RICe for Africa (NERICA) cultivars are popular amongst subsistence farmers, but little is known about their post-attachment resistance against Striga. Here, we evaluate the post-attachment resistance levels of the NERICA cultivars and their parents against ecotypes of S. hermonthica and S.asiatica, characterize the phenotype of the resistance mechanisms and determine the effect of Striga on host biomass. Some NERICA cultivars showed good broad-spectrum resistance against several Striga ecotypes, whereas others showed intermediate resistance or were very susceptible. The phenotype of a resistant interaction was often characterized by an inability of the parasite to penetrate the endodermis. Moreover, some parasites formed only a few connections to the host xylem, grew slowly and remained small. The most resistant NERICA cultivars were least damaged by Striga, although even a small number of parasites caused a reduction in above-ground host biomass. The elucidation of the molecular genetic basis of the resistance mechanisms and tolerance would allow the development of cultivars with multiple, durable resistance for use in farmers' fields.