Effect of nitrite ingestion on the bioavailability of folate in the rat.

The effect of nitrite ingestion on the intestinal deconjugation and absorption of folic acid (PGA) and brewers yeast folate was investigated using a rat bioassay and liver folate uptake as the response parameter. Male weanling Sprague Dawley rats were depleted on a low folate AIN-76A formulated basal diet for 21 days. During a 14 day repletion period, folic acid (PGA) and brewers yeast were added to provide 0.25, 0.5 and 1.0 mg of folate per kg of diet. Potassium nitrite was administered as part of the diet at 0.5%. All diets were made isonitrogenous and isocaloric. Based on a parallel line assay, the relative bioavailability of folate in the brewers yeast diet (109) was significantly higher than in the standard diet (PGA = 100). When combined with nitrite, the relative bioavailability of the PGA diet was not significantly different (101), while that of the brewers yeast diet was significantly lower than the standard diet. Concomitant ingestion of nitrite significantly reduced the bioavailability of brewers yeast folate but not that of PGA in rats. This appeared to be a direct effect of oxidation by nitrite on the more susceptible substituted folates in brewers yeast.     

Bioavailability of folate following ingestion of cholestyramine in the rat

The effect of cholestyramine ingestion on the intestinal deconjugation and absorption of folic acid (PGA) and brewers yeast folate was investigated using a rat bioassay and liver folate uptake as the response parameter. Male weanling Sprague Dawley rats were depleted on a low AIN-76A formulated basal diet for 21 days. During a 14 day repletion period folic acid (PGA) and brewers yeast were added to provide 0.25, 0.5 and 1.0 mg of folate per kg of diet. Cholestyramine was administered directly as part of the diet at 1.1%. All diets were made isonitrogenous and isocaloric. Based on a parallel line assay, the relative biological value of folate for PGA + cholestyramine (79) was significantly different from the standard diet (PGA = 100), while those for brewers yeast (88) and for brewers yeast + cholestyramine (88) did not differ from the standard diet. Ingestion of cholestyramine significantly reduced the bioavailability of PGA versus brewers yeast folate in rats.     

Anterior sacrodural attachments - Trolard's ligaments revisited

In contrast to the attention paid to the structures surrounding spinal nerve roots in the intervertebral foramina, the anterior dural attachments are largely ignored, although they have been described since the last decades of the 19th century. These anterior attachments were systematically studied in a series of 30 cadaver dissections and were found to be present in almost 94% of cases. Four types of anterior attachments were observed. The most frequent form (84%) being a system of filaments that present as a double cross vault between the dura mater and the posterior longitudinal ligament extending from L3 to S3 levels. Less frequent were sagittal filaments (30%), short strong ligaments (17%) and a median septum from L3 to the end of the dural sac (7%). No attachments were found in two cadavers. Further studies are needed to clarify the possible role of these structures in transmitting movement to the dural sac and periradicular sleeves when mobilising the last three lumbar vertebrae or the sacrum.     

Mutation screening and isoform prevalence of the follicle stimulating hormone receptor gene in women with premature ovarian failure, resistant ovary syndrome and polycystic ovary syndrome

OBJECTIVE: To determine whether mutations in the FSH receptor gene are associated with premature ovarian failure (POF) or resistant ovary syndrome (ROS) in women in the UK. To determine whether an allelic variant of the FSH receptor gene affects fertility parameters in women with polycystic ovary syndrome (PCOS). DESIGN: A mutation screen using DNA from women with POF and ROS. Restriction digest of amplified DNA from women with POF, ROS, PCOS and controls to determine allelic variant status. Fertility parameters were compared between allelic variant subgroups of women with PCOS. PATIENTS: The study population comprised 49 women with POF, 5 with ROS, 93 with PCOS and 51 controls. MEASUREMENTS: In women with PCOS, fertility and menstrual status was recorded and serum FSH and ovarian volume were measured. RESULTS: No mutation of the FSH receptor gene was found in women with POF or ROS. The allelic variant Thr307/Ser680 was found to be similarly prevalent in all study groups. The Thr307/Ser680 variant was found to have no phenotype in terms of fertility parameters in women with PCOS. CONCLUSIONS: Mutations of the FSH receptor gene are rare in women with premature ovarian failure or resistant ovary syndrome in the UK. Polymorphisms of the FSH receptor gene do not appear to have pathophysiological significance with regard to ovarian function.     

Cortical network dysfunction in musicogenic epilepsy reflecting the role of snowballing emotional processes in seizure generation: an fMRI‐EEG study

Aim. Patients suffering from musicogenic epilepsy have focal seizures triggered by auditory stimuli. In some of these patients, the emotions associated with the music appear to play a role in the process triggering the seizure, however, the significance of these emotions and the brain regions involved are unclear. In order to shed some light on this, we conducted fMRI and EEG in a case of musicogenic epilepsy. Methods. In a 32‐year‐old male patient with seizures induced by a specific piece of Russian music, we performed video‐EEG monitoring as well as simultaneous fMRI and EEG registration. Results. Video‐EEG monitoring revealed a left temporo‐frontal epileptogenic focus. During fMRI‐EEG co‐registration, BOLD signal alterations were not only found in the epileptogenic focus but also in areas known for their role in the processing of emotions. Prior to a seizure in some of these areas, BOLD contrasts exponentially increased or decreased. Conclusion. These results suggest that in our case, dysfunction of the regulation processes of the musically‐induced emotions, and not the musical stimulus itself, led to the seizures.     

Erkennen und behandeln des Status epilepticus

Convulsive status epilepticus is defined as a general or focal epileptic seizure lasting longer than 5 min or recurrent seizures without regaining consciousness between seizures. Status epilepticus is a life-threatening condition caused by underlying pathologies (e.g., stroke, meningitis, cerebral hypoxia, cerebral edema). In addition, patients are in danger of physical injury and impaired brain stem reflexes. This also applies to nonconvulsive status epilepticus, which is often characterized by an “unclear loss of consciousness”. Although it can only be diagnosed by electroencephalography, it is an important differential diagnosis in the prehospital or emergency room situation, which may be decisive for the therapeutic strategy. Benzodiazepines are the first choice treatment for status epilepticus. This article summarizes a guideline-directed therapy with different pharmaceutical substances and ways of application. A pragmatic approach for limited diagnostic and therapeutic possibilities in the emergency situation is presented.     

Telephone survey of service‐user experiences of a telephone‐based mental health triage service

The participation of service users in all aspects of mental health service delivery including policy development, service planning and evaluation is increasingly an expectation of contemporary mental health care. Although there are a growing number of publications reporting service‐user perspectives in the evaluation of mental health services, little attention has been paid to the views of service users about mental health triage services. The purpose of the study reported here was to examine service‐users' (consumers and informal carers) experiences of a telephone‐based mental health triage service. Using a framework developed from the World Health Organisation's elements of responsiveness, we conducted structured telephone interviews with service users who had contacted a telephone‐based mental health triage service in regional Victoria, Australia. The main findings of the study were that consumers experienced more difficulty than carers in accessing the service and that, although most participants were satisfied, only a minority reported being involved in decision‐making. Further work is needed to improve accessibility of mental health triage services and to investigate barriers to consumer self‐referral. Professional development and practice support systems should be established to support mental health triage nurses in the development of collaborative, consumer‐focused care.     

A duplication of 12 bp in the critical cysteine rich domain of the RET proto-oncogene results in a distinct phenotype of multiple endocrine neoplasia type 2A

Activating germline mutations in the cysteine-rich domain of the RET proto-oncogene are found in >92% of the cases of multiple endocrine neoplasia type 2A (MEN2A) and 85% of familial medullary thyroid carcinoma (FMTC). In virtually 100% of patients with identified mutations one of five cysteines is altered by a missense mutation. In a MEN2A family with 14 affected and 11 unaffected living members, hypercalcemia was diagnosed in eight patients and histological evaluation revealed parathyroid hyperplasia in all cases examined (10/10). No member of this family showed any evidence for the existence of pheochromocytoma. This is the first documentation of a family without pheochromocytoma but with a high incidence of parathyroid disease. Genetic analysis revealed the presence of an unusual heterozygous mutation in exon 11 of the RET proto-oncogene representing a duplication of 12 bp resulting in the insertion of four amino acids between codon 634 (Cys) and 635 (Arg), thus creating an additional cysteine residue.