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Sexual dimorphism has been reported in all extant echinoderm classes except crinoids, but has never been examined from a phylogenetic, biogeographical, or life-history perspective. This review provides a literature survey of sexual dimorphism in holothuroids and uses this dataset to analyze putative drivers. Sexually dimorphic genital papillae were found in Persiculida and Dendrochirotida but not in other holothuroid taxa. No planktotrophic species (feeding larvae) had known genital dimorphism, though many lecithotrophs (non-feeding larvae) displayed clear morphological differences between male and female papillae. Males with genital dimorphism had digitate or extensible papillae while females had unbranched papillae. Extensible papillae were common among males in brooding species, suggesting an adaptive advantage for certain reproductive strategies such as sperm transfer or pseudo-copulation. Digitate papillae bearing many gonopore openings were common among free-spawning, lecithotrophic males (~ 80% of species) and may serve to disperse sperm into the water column. Finally, we found that external dimorphism of the genital papillae in a case study of the dendrochirotid Cucumaria frondosa (Gunnerus, 1767) provided a reliable method of sex determination. These results suggest that genital dimorphism among dendrochirotid sea cucumbers is widespread and may facilitate determination of sex in the field where sacrificing animals is not practical.

Huntington’s disease (HD) is caused by an abnormal expansion of CAG trinucleotide repeats encoding polyglutamine (polyQ) in the first exon of the huntingtin (htt) gene. Despite considerable efforts, the pathogenesis of Huntington’s disease (HD) remains largely unclear due to a paucity of models that can reliably reproduce the pathological characteristics of HD. Here, we report a neuronal cell model of HD using the previously established tetracycline regulated rat neuroprogenitor cell line, HC2S2. Stable expression of enhanced green fluorescence protein (EGFP) tagged-htt exon 1 (referred to as 28Q and 74Q, respectively) in the HC2S2 cells did not affect rapid neuronal differentiation. However, compared to the cells expressing wild type htt, the cell line expressing mutant htt showed an increase in time-dependent cell death and neuritic degeneration, and displayed increased vulnerability to oxidative stress. Increased protein aggregation during the process of neuronal aging or when the cells were exposed to oxidative stress reagents was detected in the cell line expressing 74Q but not in its counterpart. These results suggest that the neuroprogenitor cell lines mimic the major neuropathological characteristics of HD and may provide a useful tool for studying the neuropathogenesis of HD and for high-throughput screening of therapeutic compounds.

Melanoma of the anorectum represents

Acute stoma prolapse most commonly occurs following emergency surgery, frequently in patients with significant medical co-morbidities. Correction often requires re-laparotomy and resiting of the stoma, placing an already frail patient at risk of further morbidity. An elderly patient experienced an end colostomy prolapse 14 days following emergency laparotomy. A novel technique was employed using the CONTOUR® curved stapling device to excise the prolapsed segment, under a brief period of intravenous sedation, thereby avoiding the sequelae of general anaesthetic. No complications were experienced, and the patient was deemed fit for discharge 5-days post re-intervention.

We present a case of recurrent variceal bleeding due to subtotal occlusion of the splenoportal junction by a pancreatic carcinoma. This was effectively treated by transhepatic venous angioplasty and stenting.

Summary Participant modelling, a behaviourally-orientated treatment technique, is an effect method of treating phobias associated with minor medical procedures or apparatus such as needles or intravenous catheters. The steps in this technique are described and two cases of severe needle phobias successfully treated with participant modelling are presented to illustrate further its application.

Ten children developed intussusception after laparotomy. The bowel obstruction caused by the intussusception was evident within 8 days of major laparotomy in 8 children and within 39 days in the other two. It developed after the usual postoperative laparotomy ileus, and did not respond to normal non-operative treatment not even to a barium enema. There was one palpable abdominal mass and no rectal bleeding. Only at surgery was the correct diagnosis made. Eight of 10 intussusceptions affected only the small-bowel; most of them were ileoileal, but 2 were ileocolic. Seven of the 10 intussusceptions needed only manual reduction. Postoperative recovery was uneventful.

Stumpy is a new chondrodystrophic mutant in the mouse. The condition is inherited as a fully penetrant Mendelian recessive, and is not allelic with brachymorphic, achondroplasia, or stubby-three similar, previously described mutants. No chromosomal position has yet been assigned to the gene. Phenotypically, stumpy mice are chondrodystrophic dwarfs with all cartilage-formed bones in the skeleton affected. The condition differs from the usual chondrodystrophy described in mice in that proximal elements in the limbs are affected more than distal ones.

From Abstract: "Certain characteristics of the neutron field from this unshielded reactor were measured. The activation of gold, manganese, sulfur, cadmium-covered gold, and cadmium-covered manganese was determined as a function of distance from the reactor and of depth in the ground. The data show how those parameters, important for calculating neutron-induced activity in the soil, vary as a function of the height of the source and the slant range from the source."

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The oxidation kinetics, in high pressure CO 2 , of Fe-based alloys and steels containing up to 12%Cr can undergo a transition from protective (reducing) rates of oxidation to relatively rapid linear oxidation rates (breakaway oxidation). The effects of small additions of silicon to pure iron and Fe-Cr binary alloys, and the effects of silicon content of steels on oxidation has been studied. Additions of silicon to pure Fe decreased the protective oxidation rates, increased times to breakaway and decreased post-breakaway rates. The morphologies of the oxide scales and the distribution of silicon were examined by optical and electron optical techniques. It is proposed that the beneficial effects of silicon are due to the blocking of short circuit diffusion paths in the protective oxide scale and to the promotion of graphite nucleation in the metal. The latter process provides a ‘sink’ for the carbon produced by the oxidation/carburization reaction and prevents the deleterious nucleation of Fe 3 C at the metal-oxide interface. Additions of silicon to Fe—9 %Cr and Fe—12 %Cr alloys greatly reduced protective oxidation rates and increased times to breakaway by promoting the formation of thin chromium-rich sesquioxide scales rather than double layered Fe 3 O 4 -Fe-Cr spinel scales. With increasing silicon content the protective oxidation rates of Fe—9 %Cr steels decreased but sesquioxide scales were not formed. At high temperatures high silicon contents promoted the formation of a chromiumenriched spinel healing layer at the metal—oxide interface.