Targeted association analysis identified japonica rice varieties achieving Na(+)/K (+) homeostasis without the allelic make-up of the salt tolerant indica variety Nona Bokra

During the last decade, a large number of QTLs and candidate genes for rice tolerance to salinity have been reported. Using 124 SNP and 52 SSR markers, we targeted 14 QTLs and 65 candidate genes for association mapping within the European Rice Core collection (ERCC) comprising 180 japonica accessions. Significant differences in phenotypic response to salinity were observed. Nineteen distinct loci significantly associated with one or more phenotypic response traits were detected. Linkage disequilibrium between these loci was extremely low, indicating a random distribution of favourable alleles in the ERCC. Analysis of the function of these loci indicated that all major tolerance mechanisms were present in the ERCC although the useful level of expression of the different mechanisms was scattered among different accessions. Under moderate salinity stress some accessions achieved the same level of control of Na(+) concentration and Na(+)/K(+) equilibrium as the indica reference variety for salinity tolerance Nona Bokra, although without sharing the same alleles at several loci associated with Na(+) concentration. This suggests (a) differences between indica and japonica subspecies in the effect of QTLs and genes involved in salinity tolerance and (b) further potential for the improvement of tolerance to salinity above the tolerance level of Nona Bokra, provided the underlying mechanisms are complementary at the whole plant level. No accession carried all favourable alleles, or showed the best phenotypic responses for all traits measured. At least nine accessions were needed to assemble the favourable alleles and all the best phenotypic responses. An effective strategy for the accumulation of the favourable alleles would be marker-assisted population improvement.

[Tuberculous meningitis in an immunocompetent adult: contribution of cerebral imaging techniques to the diagnosis and follow-up]

We have studied 5 men, mean age 47 years, affected by tuberculous meningitis (TM) without documented immunodepression. The diagnosis of TM was supported by clinical and biological investigations and confirmed by the cultures of CSF. All the patients received a four-drug combination therapy and steroids. No drug resistance of the bacilli was observed. Cerebral imaging by CT and MRI was rarely diagnostic but most useful during the follow-up. All the patients developed complications including tuberculomas (5), hydrocephalus (4), ischemic lesions (2), arachnoiditis (1) and abscess of spinal cord (1). Four patients recovered and one died. The mean duration of the follow-up was 16 months. MRI was more sensitive than CT scan to identify inflammatory lesions such as granulomas, angeitis or arachnoiditis and to follow their outcome. Tuberculomas and hydrocephalus were easily diagnosed by CT scan with contrast enhancement. Recommendations of sequential imaging are suggested to identify unexpected or asymptomatic complications of TM during therapy and evaluate the outcome.

[Evaluation of pulmonary arterial hypertension by Doppler echocardiography in chronic respiratory insufficiency]

The usefulness of doppler-echocardiography for the assessment of pulmonary arterial hypertension in patients with chronic respiratory failure was evaluated in 24 consecutive patients with chronic obstructive lung disease. Seventeen of these 24 patients (71 p. 100) who had tricuspid valve regurgitation analysable by the continuous wave doppler technique were selected as study group; they included 15 men and 2 women aged from 33 to 78 years (mean 63 years). The highest maximum velocity value (method A) or the maximum velocity value averaged on several cycles (method B) of the tricuspid regurgitation jet was used to calculate the right ventriculo-atrial pressure gradient, using Bernouilli's equation. Right atrial pressure was determined by three methods: haemodynamic measurement, clinical evaluation or attribution of an arbitrary 10 mmHg value. The pulsed doppler study of the pulmonary ejection flow included measurement of the acceleration time and calculation of the acceleration time/ejection time ratio. The usual echocardiographic parameters were measured. Catheterization was performed 2.5 days on average after the doppler study. Correlations between doppler examination and catheterization to evaluate the right ventricular systolic pressure were significant (p less than 0.001) and better with method B than with method A. Depending on the method employed to evaluate the right atrial pressure, the correlation coefficients obtained with method B were: 0.93 (haemodynamic measurement), 0.91 (clinical evaluation) and 0.88 (arbitrary value of 10 mmHg). The right ventricular systolic pressure evaluated by doppler ultrasound using method B and by clinical evaluation of the right atrial pressure was 47 +/- 12 mmHg (22 to 70 mmHg), as against 51 +/- 13 mmHg (28 to 74 mmHg) measured by catheterization.(ABSTRACT TRUNCATED AT 250 WORDS)

[Acquired systemo-pulmonary fistula after pleurectomy responsible for a continuous thoracic murmur]

Systemo-pulmonary fistulae are rare. The case of a 27 year-old man, hospitalized for exploration of a continuous thoracic murmur, is reported. A right pleurectomy had been performed 2 years previously because of a recurrent spontaneous pneumothorax, and no murmur was present at that time. Angiography showed a systemo-pulmonary fistula with the right internal mammary artery and branches of the right axillary artery as afferent vessels, and the right pulmonary arteries and veins as efferent vessels. Blood gases measurements demonstrated a left-right shunt. The acquired nature of the fistula was suspected because of the history of right pleurectomy and the acquired nature of the murmur. There was no indication for surgery because of the complexity of the fistula and the absence of symptoms.

Adjuvant immunotherapy with nonviable Mycobacterium smegmatis in resected primary lung carcinoma. A randomized clinical trial of 219 patients

Two hundred and nineteen patients with resected lung carcinoma were randomized 3 weeks after surgery between two treatment arms: a control group (110 cases) and an immunotherapy group (109 cases). The immunostimulant was a nonviable saprophytic mycobacterium, M. smegmatis, given monthly by subcutaneous injection in four sites. The two groups were equivalent in terms of prognostic factors, including a nonsignificant difference favoring the control group based on the N (node) classification. This interim analysis was carried out on June 1, 1981. Treatment comparison by the log-rank test did not show any significant differences between these two groups in regards to disease-free interval and overall survival. There was no significant difference between the two groups after stratification of the comparison according to the N classification or adjustment with a subset of eight prognostic parameters through the Cox model. The initially expected difference (20% 1-year survival) will probably not be achieved, given these interim results, but patients will continue to be treated and followed-up according to the protocol as to allow further evaluation of this nonspecific immunotherapy.