Seed ecology of the geophyte Conopodium majus (Apiaceae), indicator species of ancient woodland understories and oligotrophic meadows

Conopodium majus is a geophyte with pseudomonocotyly, distributed in Atlantic Europe. It is an indicator of two declining European habitats: ancient woodland understories and oligotrophic hay meadows. Attempts to reintroduce it by seed have been hindered by scarce seedling emergence and limited knowledge of its seed biology. Micro-CT scanning was used to assess pseudomonocotyly. Embryo growth and germination were studied in the laboratory and the field, using dissection and image analysis. The effects of temperature, light, nitrate and GA₃ on germination were tested. Seed desiccation tolerance was investigated by storage at different RHs and by drying seeds at different stages of embryo growth. Seeds possess morphological but not physiological dormancy. Embryo growth and germination were promoted by temperatures between 0 and 5 °C, arrested above 10 °C, and indifferent to alternating temperatures, light, nitrate and GA₃ . Pseudomonocotyly appears to result from cotyledon fusion. While seeds tolerated drying to 15% RH and storage for 1 year at 20 °C, viability was lost when storage was at 60% RH. Seeds imbibed at 5 °C for 84 days had significant internal embryo growth but were still able to tolerate drying to 15% RH. Reproduction by seed in C. majus follows a strategy shared by geophytes adapted to deciduous temperate forests. The evolution of fused cotyledons may enable the radicle and the hypocotyl to reach deeper into the soil where a tuber can develop. The embryo is capable of growth within the seed at low temperatures so that germination is timed for early spring.

Root cone angle is enlarged in docs1 LRR-RLK mutants in rice

BACKGROUND

The DEFECTIVE IN OUTER CELL LAYER SPECIFICATION 1 (DOCS1) gene belongs to the Leucine-Rich Repeat Receptor-Like Kinase (LRR-RLK) subfamily. It has been discovered few years ago in Oryza sativa (rice) in a screen to isolate mutants with defects in sensitivity to aluminum. The c68 (docs1-1) mutant possessed a nonsense mutation in the C-terminal part of the DOCS1 kinase domain.

FINDINGS

We have generated a new loss-of-function mutation in the DOCS1 gene (docs1-2) using the CRISPR-Cas9 technology. This new loss-of-function mutant and docs1-1 present similar phenotypes suggesting the original docs1-1 was a null allele. Besides the aluminum sensitivity phenotype, both docs1 mutants shared also several root phenotypes described previously: less root hairs and mixed identities of the outer cell layers. Moreover, our new results suggest that DOCS1 could also play a role in root cap development. We hypothesized these docs1 root phenotypes may affect gravity responses. As expected, in seedlings, the early gravitropic response was delayed. Furthermore, at adult stage, the root gravitropic set angle of docs1 mutants was also affected since docs1 mutant plants displayed larger root cone angles.

CONCLUSIONS

All these observations add new insights into the DOCS1 gene function in gravitropic responses at several stages of plant development.

ASPP2 deficiency causes features of 1q41q42 microdeletion syndrome

Chromosomal abnormalities are implicated in a substantial number of human developmental syndromes, but for many such disorders little is known about the causative genes. The recently described 1q41q42 microdeletion syndrome is characterized by characteristic dysmorphic features, intellectual disability and brain morphological abnormalities, but the precise genetic basis for these abnormalities remains unknown. Here, our detailed analysis of the genetic abnormalities of 1q41q42 microdeletion cases identified TP53BP2, which encodes apoptosis-stimulating protein of p53 2 (ASPP2), as a candidate gene for brain abnormalities. Consistent with this, Trp53bp2-deficient mice show dilation of lateral ventricles resembling the phenotype of 1q41q42 microdeletion patients. Trp53bp2 deficiency causes 100% neonatal lethality in the C57BL/6 background associated with a high incidence of neural tube defects and a range of developmental abnormalities such as congenital heart defects, coloboma, microphthalmia, urogenital and craniofacial abnormalities. Interestingly, abnormalities show a high degree of overlap with 1q41q42 microdeletion-associated abnormalities. These findings identify TP53BP2 as a strong candidate causative gene for central nervous system (CNS) defects in 1q41q42 microdeletion syndrome, and open new avenues for investigation of the mechanisms underlying CNS abnormalities.

Randomized trial of a multidisciplinary lifestyle intervention in HIV-infected patients with moderate-high cardiovascular risk

OBJECTIVE

To assess the impact of a multidisciplinary lifestyle intervention on cardiovascular risk and carotid intima-media thickness (c-IMT) in HIV-infected patients with Framingham scores (FS) > 10%.

DESIGN

Randomized pilot study; follow-up 36 months.

METHODS

Virologically suppressed adult HIV-1-infected patients with FS >10% were randomized 1:1 to the intervention group (multidisciplinary lifestyle intervention) or control group (routine care). At baseline and months 12, 24 and 36, lipid parameters were analyzed and carotid ultrasound was performed to determine c-IMT and presence of plaques. Biomarkers were measured at baseline and month 36. The primary endpoints were lipid and FS changes at 36 months.

RESULTS

Fifty-four patients were included, 27 in each arm. Median age was 50.5 years, all patients but one were men, and FS was 16.5%. Relative to controls, total and LDL cholesterol had significantly decreased in the intervention group at 24 months (p = 0.039, p = 0.011, respectively). However, no differences between groups were found at month 36 in lipid variables, neither in FS. Tobacco use decreased in the intervention group (p = 0.031). At baseline, 74.5% of patients had subclinical atherosclerosis, and at month 36, we observed a progression in c-IMT that was greater in the intervention group (p = 0.030). D-dimer increased (p = 0.027) and soluble intercellular adhesion molecule-1 decreased (p = 0.018) at 36 months.

CONCLUSIONS

In this cohort of HIV-infected patients with FS>10% and a high percentage of subclinical atherosclerosis, a multidisciplinary lifestyle intervention resulted in a slight improvement in some cardiovascular risk factors and the FS during the first 2 years, but did not prevent c-IMT progression.

Long-term improvement of slow-channel congenital myasthenic syndrome with fluoxetine

We report on a 15-year-old patient who was diagnosed with congenital myasthenic syndrome (CMS) at the age of 7 months. At initial diagnosis, the CMS was not further characterized. The patient was treated for several years with the anticholinesterase drug (Mestinon), without clinical benefit. The patient deteriorated progressively and became dependent on home nocturnal ventilatory support, being unable to take part in daily life activities at age of 12 years. At age 14, the slow-channel syndrome mutation CHRNE L269F (805C>T) was detected and acetylcholinesterase inhibitor therapy was immediately stopped. Fluoxetine therapy was started and gradually increased over 2 months. The boy improved dramatically in strength and endurance and was taken off ventilatory support 1 month after the fluoxetine therapy was initiated. The clinical improvement was confirmed by functional respiratory and electrophysiological tests.

[Thymectomy in juvenile myasthenia gravis]

INTRODUCTION

Juvenile myasthenia gravis (JMG) is an infrequent autoimmune disease, the symptoms and therapeutic handling of which do not differ from those of the adult forms. Chronic treatment with corticoids very often causes side effects in childhood, which is why patients are being submitted to thymectomies at younger ages with better results. AIMS. To analyse the clinical and evolutionary profile of JMG treated by thymectomy in our centre.

PATIENTS AND METHODS

We report the case of four girls aged between 5 and 13 who were diagnosed as suffering from generalised myasthenia gravis (MG) with bulbar affectation. One of them started with a myasthenic crisis. The four of them were submitted to Tensilon s test, an electrophysiological study, determination of AChR, thoracic CT, and study of autoimmunity and thyroid functioning. After surgery the thymus was analysed histologically.

RESULTS

They all gave positive in Tensilon s test and were seropositive for AChR. They were treated with anticholinesterases, up to the maximum tolerated dose, and corticoids, without complete remission being accomplished and so they were submitted to a thymectomy in the first year of evolution. In three cases surgical approach was transsternal and in the other by means of a videothoracoscope. All the thymuses showed lymphoid hyperplasia. After a variable follow up the girls are at present asymptomatic, although none of them has been able to completely give up the pharmacological treatment.

CONCLUSIONS

Thymectomy is one of the mainstays of treatment for JMG. The ever more frequent use of videothoracoscopic techniques achieves results that are similar to those obtained by conventional surgery but with fewer post operative and aesthetic problems

[A ketogenic diet: is this a valid alternative in refractory epilepsy]

INTRODUCTION

The ketogenic diet was first used in refractory epilepsy of childhood in the early 1920s. It was forgotten when new antiepileptic drugs were introduced, but recently has been used again. Although its efficacy in the treatment of epilepsy, in some patients, is beyond doubt, its mechanism of action is still not clear. There are three types of diet: the classical diet with a proportion of 4:1 of long chain fatty acids, with MCT oil and with modified MCT oil.

OBJECTIVE

To present a protocol recently designed in our hospital. We include the type of diet, form of onset, subsequent follow up of complications, clinical and electroencephalographic response and side effects seen in the patients.

PATIENTS AND METHODS

Introduction of the ketogenic diet with MCT oil in six patients aged between 2 and 11 years, with various types of epilepsy, all resistant to treatment, who had been unsuccessfully treated for 28 months in one case and between 4 and 6 months in the others. We evaluated the response on the criteria of Huttenlocher and Panic electroencephalograms.

RESULTS

Two of the patients improved with good control of their disorder and the EEG became normal. No serious side effects were seen apart from gastrointestinal symptoms which improved when the quantity of MCT oil was reduced.

CONCLUSIONS

In patients with drug resistant epilepsy it is convenient to have a guideline for treatment using a ketogenic diet. It is also useful to have a multi disciplinary team for management, follow up to detect late side effects and obtain the cooperation of the patient s family in following the protocol.

[Rett's syndrome in the Spanish population]

INTRODUCTION AND OBJECTIVE

Rett syndrome was described in 1966 and became known through the English medical literature in 1983. There are typical and atypical forms. The objective of this study was to record the cases diagnosed in Spain and discover their clinical characteristics in order to describe its phenotype and geographical distribution.

PATIENTS AND METHODS

We know of 207 cases and have obtained the records of 168 of these patients. A protocol and data collection programme has been developed giving the criteria for inclusion, and data which support or exclude this. Data collection was by post and the data for identification were the date of birth and the initials of the name and two surnames. With these variables, double-registering of patients was almost impossible. A statistical study with descriptive analysis and a study of continuous and alternating variables was immediately done.

RESULTS AND CONCLUSION

The results gave the main characteristics, the differences between typical and atypical cases and a comparative study of variables. It has given clinical data which may be useful for prognosis of the condition in the future.

[Respiratory chain and pyruvate metabolism deficiencies in pediatric patients: evaluation of biochemical tests for selective screening]

INTRODUCTION

The correct selection of pediatric patients with clinical suspicion of mitochondrial diseases is the first step to achieve a definitive diagnosis.

MATERIAL AND METHODS

The results of the initial biochemical tests obtained in 35 children diagnosed of respiratory chain or pyruvate metabolism defects were reviewed. The efficiency of basal determinations (lactate, pyruvate, ketone bodies, amino and organic acids and carnitine), cerebrospinal fluid (CSF) analysis, and dynamic tests (exercise, glucose loading and glucose oxidation by lymphocytes) was discussed.

RESULTS

Plasma lactate and alanine, and CSF metabolites were the most informative measurements in basal status. Urine organic acids were very useful to confirm the initial suspicion. Glucose loading was the most informative and reliable challenge test for pediatric population, while exercise test was especially useful for older children with fatigability or peripheral nervous system involvement.

CONCLUSIONS

Glucose oxidation by lymphocytes might be applied when the other dynamic tests can not be performed or are not informative.

A new case of multiple mitochondrial enzyme deficiencies with decreased amount of heat shock protein 60

Heat shock protein 60 (hsp60) is a mitochondrial matrix protein involved in the folding and correct assembly of polypeptides into complex mitochondrial enzymes. Its deficiency has recently been described as the most likely primary cause of congenital lactic acidaemia with multiple mitochondrial enzyme deficiencies in a female patient. We describe a new case of a girl with a substantially decreased amount of hsp60 in cultured fibroblasts. She presented from birth with hypotonia, unusual facial features, feeding difficulties and failure to thrive. Death occurred at age 4.5 years. Biochemical findings included metabolic acidosis with lactic acidaemia, hyperammonaemia and intermittent ketosis. In contrast to the previously reported case, organic acid analysis showed an altered profile throughout her life. In agreement with this profile, various mitochondrial enzyme activities were deficient in cultured fibroblasts, including enzymes of the respiratory chain and the Krebs cycle, the pyruvate dehydrogenase complex and the mitochondrial biotindependent carboxylases. Fibroblast mitochondria showed ultrastructural abnormalities, were swollen, and were mainly localized around the nucleus. The description of a second case of multiple mitochondrial enzyme deficiencies with reduced amount of hsp60 supports the idea that hsp60 deficiency might be a more common cause of mitochondrial disease. This opens new possibilities for the diagnosis and understanding of congenital lactic acidaemia.

Tocopherol in inborn errors of intermediary metabolism

Red blood cell tocopherol was measured in a group of 92 children with inborn errors of intermediary metabolism to evaluate the peroxidative damage in different mitochondrial and cytosolic defects, and to consider the need for treatment or vitamin supplementation. Tocopherol was determined by HPLC with UV detection. Results were expressed in nanomoles red blood cell tocopherol per gram protein. Significant differences (Mann-Whitney; P < 0.001) were found between tocopherol levels in untreated patients: 19 with mitochondrial defects versus 23 with cytosolic enzyme or transport defects, and versus 58 age-matched reference values. In conclusion, mitochondrial enzyme deficiencies, either amino and organic acidurias or defects of energy metabolism, seem to produce an excess of free radicals with the consequent utilization of tocopherol as antioxidant. This is not apparent in the cytosolic enzyme defects studied, whose tocopherol levels are in the normal range. Treatment with tocopherol completely corrects the deficient antioxidant status.

[Ataxia telangiectasia: review of 13 new cases]

We report the review of 13 patients who were diagnosed of ataxia telangiectasia before 6 years of age. All of them manifested cerebelous ataxia, oculocutaneus telangiectasias (11), sinopulmonary infections (9), dystonia (9), oculomotor apraxia (9) and Burkitt linfoma (1). We analyse the most common presentation of the disease in early stages and the complementary studies performed. The prompt diagnosis allow us a better control of infections, malignant process and finally the possibility of genetic counseling.

[Primary leptomeningeal melanomatosis in a 6-year-old child]

A case of primary leptomeningeal melanomatosis without cutaneous lesions is reported. The clinical findings for a six months period were: intracranial hypertension syndrome, progressive cranial polineuropathy and a spinal involvement in a six years old child. CT brain scan showed enlarged subarachnoid spaces without contrast enhancement. MRI brain scan evidenced furthermore a focal lesion in right talamus. MRI spinal scan was normal. Examination of CSF showed elevated protein and reduced glucose concentrations as well as mild pleocytosis. Serologies and cultures investigating viral, bacterial, mycobacterial, fungal or parasitic infections resulted negative. CSF cytologic examination failed to show malignant cells. Postmortem diagnosis after neuropathological examination was made. This is an uncommon case of primary leptomeningeal melanomatosis, presenting the difficulty of diagnosis when cutaneous lesions are not present.

Relationship between levels of Clostridium difficile toxin A and toxin B and cecal lesions in gnotobiotic mice

Various Clostridium difficile strains were studied with respect to their pathogenicity in monoassociated mice in relation to levels of toxin A and toxin B in vivo and in vitro. Two strains which were the most potent toxin producers in vitro induced mortality (100%); mice monoassociated with these strains were found to have high levels of both toxins in their ceca and an intense cecal epithelial ulceration together with a severe inflammatory process. No mortality was observed with the other strains. Strains which were moderately toxinogenic in vitro induced inflammation of the cecum but no ulceration, and no toxin A was found. Inflammation intensity was not related to toxin B levels. After 3 weeks, ceca returned to normal in spite of a chronic cytotoxin production. When compared with in vitro results, which showed a good correlation between the levels of the two toxins, toxin A amounts in vivo were found to be lowered relative to toxin B levels. The lack of detectable toxin A levels in animals infected with all but the two most highly toxinogenic strains prevented death. This work points out the importance of investigation of toxin A for the understanding of C. difficile pathogenicity.

[Neonatal myasthenia of persistent course: apropos of 2 cases in siblings]

Authors report 2 siblings with neonatal myasthenia gravis of persistent course. The first of them died at 10 months old probably of bronchial aspiration. His sister aged 3 years continues symptomatic requiring anticholinesterase medication. Comparing their patients with those from literature, they comment clinical, diagnostic, therapeutic and specially, classificatory aspects of this entity.

Comparison of the effects of various flavonoids on ethoxycoumarin deethylase activity of rat intestinal and hepatic microsomes

Fifteen flavonoids were examined for their effects on the activity of 7-ethoxycoumarin O-deethylase in rat hepatic and intestinal microsomes. The effect depended on both the chemical structure of the flavonoid and the origin of the microsomes. Polyhydroxylated flavonoids with a C2-C3 double bond (flavones and flavonols) were more effective inhibitors of the enzyme in both hepatic and intestinal microsomes than were the reduced homologues (flavanonols, flavanones and flavan-3-ols). In contrast, flavones lacking hydroxyl substituents (e.g. 5,6-benzoflavone, 7,8-benzoflavone and flavone) increased ethoxycoumarin deethylase activity in liver microsomes although they had an inhibitory effect in intestinal microsomes.

Dystonia as a presenting sign of subacute necrotising encephalomyelopathy in infancy

A case of subacute necrotising encephalomyelopathy is reported with such note worthy features as early onset, dystonic manifestations and the presence of low attenuation areas in the basal ganglia on computerised tomography of the brain. Laboratory findings were normal and the diagnosis was confirmed at postmortem examination.

[Cardiovascular risk factors in headquarters staff of the World Health Organization]

Analysis of 2333 medical files of the World Health Organization's headquarters staff in Geneva gives insight into the epidemiology of cardiovascular risk factors in nationals originating from 67 different countries but living in the same environment. The study confirms well established facts such as the prevalence of hypertension (HT) with respect to sex, age, and period of observation, its consequences and interrelation with high cholesterol levels, diabetes, and obesity. The importance of a medical service with emphasis on prevention is stressed. Major differences in relation to geographic origin are noted for men. The highest percentage of HT (32%) is noted for staff members from Germanic countries. There is a concentric decrease according to nationality: 29 to 25% for the other countries of Central, Western, and Southern Europe, 23 to 18% for the USSR, Arab countries and North America, 9 to 6% for South East and Eastern Asia and African countries south of the Sahara (p less than 0.05 between the extremes). India and Australia do not fit the pattern of concentric decrease, since a high percentage of men in those countries have HT. As the number of files available was insufficient to carry out the same analysis for women or to determine other factors of cardiovascular risk, the study will be extended to cover the staff of other International Organizations in Geneva.

[Unilateral brain edema in a case of Reye's syndrome (author's transl)]

A case of Reye's syndrome is reported with peculiar characteristics of neurological focality and important cerebral edema of the opposite side. The present knowledge of genetic factors in the development of Reye's syndrome encephalopaty is briefly discussed and, also, the possible vascular role in this definite case.

[Factors of arterial and renal complications in diabetes]

In a population of 744 diabetics composed mainly of elderly female patients, 172 developed hypertension after the onset of diabetes. Compared to normotensive diabetics, they had an increased prevalence of diabetic retinopathy (p less than 0.001), cerebral accidents, ischemic disorders of the lower limbs and a decreased glomerular filtration rate (p less than 0.05); they are frequently insulin-dependent and difficult to manage. In 173 other indivuals the diabetes emerged several years after the hypertension. This group was characterized by relatively easily controlled blood sugar and increased prevalence of angina and myocardial infarction (p less than 0.001). The association of hypercholesteremia with hypertension increases the risk of coronary disease (p less than 0.02) and, to a lesser degree, of glomerular insufficiency. The prevalence of coronary symptoms increases with obesity (p less than 0.05) while retinopathy increases with insulin dependence (p less than 0.001). From this information it may be concluded that the importance of various risk factors in the diabetic chiefly varies according to the vascular territory involved: cerebral vascular accidents occur mainly in hypertensives, while the presence of retinopathies, proteinuria and peripheral ischemia is directly related to the diabetes and particularly to insulin dependence. The risk of coronary lesions increases considerably when hypertension is added to the diabetes, with an even greater risk in the case of a diabetic, hypertensive, hypercholesterolemic nexus.