Recent changes in reproductive phenology of a K-selected aquatic insect predator, Belostoma flumineum Say (Heteroptera, Belostomatidae).

The timing of critical events like mating, migration, and development has noticeably and recently shifted in many populations of diverse organisms. Here, we report a change in the breeding phenology of giant waterbugs, Belostoma flumineum Say (Heteroptera, Belostomatidae), in the northeastern United States. Waterbugs collected in 2005 and 2006 exhibited previously typical patterns of mating and reproduction: two annual reproductive peaks in which overwintered adults mated in the spring and young adults from a new generation mated in the fall. In 2012 and 2015, despite similar sampling effort, we detected no fall breeding activity in the study area. Reproductive behaviour under controlled laboratory conditions was also different between the earlier (2005 and 2006) and recent (2012 and 2015) years: waterbugs collected in recent years exhibited significant delays in reproduction (>30 days) under similar photoperiod and thermal conditions. We discuss potential causes of this dramatic change in reproductive behaviour, such as climate change, as well as possible negative impacts of the absence of fall reproduction on populations of B. flumineum in the study region.

Diagnosis of a posterior fossa tumour by magnetic resonance imaging.

The application of magnetic resonance imaging as a diagnostic tool for diseases of the central nervous system is described in the case of a 17-year-old girl who presented with neurological symptoms in January 1986. A comparison is made with the results of computed tomography in the diagnosis of the disease, which proved to be a grade-III glioma that appeared as a lesion of the posterior fossa. The patient recovered uneventfully after radiotherapy. It is suggested that MRI should be considered seriously as a first line of investigation in any suspected lesion of the posterior fossa.

Developmental anomalies affecting the fourth ventricular outflow region: a report of four cases.

Developmental anomalies affecting the hind brain, cerebellum and spinal cord with associated malformations of the skull base and cervical spine, show a wide degree of variability and overlap so that cases are often difficult to classify into a fixed category such as the Arnold-Chiari malformation Type 1 or Type 2, or the Dandy-Walker syndrome. The 4 cases presented here illustrate this problem and offer support for the hypothesis that these conditions may be merely the varying expression of a common pathological process. The CT brain scan may prove to be a valuable means of allowing early recognition of these anomalies so that effective surgical treatment can be given at an early stage in their natural history, possibly thereby preventing the progression or development of central cord cavitation with its significant and permanent disabilities.

Hypoglycaemia secondary to pancreatic islet cell adenoma.

The detailed case histories of 5 patients with hypoglycaemic episodes secondary to islet cell adenoma of the pancreas are presented. Clinical recognition of this syndrome remains the major problem but a full and detailed medical history is usually strongly suggestive of the correct diagnosis. The clinical diagnosis is confirmed by the repeated demonstrated that: 1) Symptomatic episodes produced by fasting are in fact due to hypoglycaemia (plasma glucose level less than 2.5 mmol/litre) 2) Such episodes are relieved by glucose administration 3) Concomitant hyperinsulinaemia is present (serum insulin greater than 8 micro-units/ml in the fasting state). Surgical resection of the adenoma produces a complete cure but the identification of the lesion at operation may be difficult and preoperative means of accurate localisation may be needed.

Multiple progressive intracranial arterial occlusions ('moyamoya' disease).

Four adult female patients with moyamoya vessels are described. Hypertension and hyperlipidaemia were discovered in three patients. Vessels similar to moyamoya vessels were seen in the orbital and cortical collateral vessels as well as in the basal ganglia region. Attention should now be paid to the aetiological rather than the descriptive aspects of the disorder. An empirical trial of corticosteroids is worth while. Risk factors such as hypertension, hyperlipidaemia, and smoking should be eliminated.

Butirosin, a new aminoglycosidic antibiotic complex: bacterial origin and some microbiological studies.

Butirosin, a new aminoglycosidic antibiotic complex, was produced by submerged fermentation with each of two strains of Bacillus circulans. A paper-disc, agar-diffusion assay which employs Escherichia coli (P-D 04863) as the test organism has been developed. Shaken-flask and stirred-jar fermentations in a medium containing glycerol, soybean meal, meat peptone, ammonium chloride, and calcium carbonate reach titers of 500 to 700 mug of butirosin base per ml. Butirosin is active against several gram-positive and gram-negative bacteria including Pseudomonas aeruginosa.

The form and distribution of the surface evoked responses in cerebellar cortex from intercostal nerves in the cat.

1. The form and distribution of the cerebellar evoked responses to electrical stimulation of intercostal and other thoracic segmental nerves were investigated in anaesthetized cats.2. Low intensity stimulation (< 2 x nerve threshold) evoked short latency, low amplitude (< 20 muV), initially surface positive responses which could only be distinguished with certainty from the electrocorticogram with averaging.3. On the basis of experiments involving sectioning of afferent tracts it is concluded that intercostal evoked responses of less than 7.0 msec latency are conducted in dorsal spino-cerebellar, ventral spino-cerebellar and dorsal column (cuneo-cerebellar) pathways.4. The surface positive waves have a highly punctate distribution with a steep potential gradient extending over an area of about 1 mm diameter. It is postulated that these small fields represent activation of single or few mossy fibre inputs.5. Short latency responses to thoracic inputs were found only in the ipsilateral intermediate cortex and lateral margin of the vermis of the anterior lobe (lateral two thirds of Larsell's lobules IV and V of the accessible cortex). The responses were distributed throughout the fore and hind limb areas of the anterior lobe and no rostro-caudal or medio-lateral segmental organization was seen.6. It is suggested that the overlapping distribution of thoracic and fore and hind limb mossy fibre inputs within the cerebellar cortex provides an anatomical basis for the integration of information from the trunk and from the limbs.