Crenarchaeota affiliated with group 1.1b are prevalent in coastal mineral soils of the Ross Sea region of Antarctica.

The objective of this study was to examine the presence and diversity of Archaea within mineral and ornithogenic soils from 12 locations across the Ross Sea region. Archaea were not abundant but DNA sufficient for producing 16S rRNA gene clone libraries was extracted from 18 of 51 soil samples, from four locations. A total of 1452 clones were analysed by restriction fragment length polymorphism and assigned to 43 operational taxonomic units from which representatives were sequenced. Archaea were primarily restricted to coastal mineral soils which showed a predominance of Crenarchaeota belonging to group 1.1b (> 99% of clones). These clones were assigned to six clusters (A through F), based on shared identity to sequences in the GenBank database. Ordination indicated that soil chemistry and water content determined archaeal community structure. This is the first comprehensive study of the archaeal community in Antarctic soils and as such provides a reference point for further investigation of microbial function in this environment.

Bacterial diversity associated with ornithogenic soil of the Ross Sea region, Antarctica.

In the Ross Sea region of Antarctica, ornithogenic soils form on land under Adélie Penguin rookeries. Compared with mineral soils of the Ross Sea region, ornithogenic soils are generally high in microbial biomass, organic carbon, and total nitrogen and phosphorus, with high electrical conductivity and large variations in pH. The objective of this study was to assess the bacterial composition of ornithogenic soils from Cape Hallett and Cape Bird in the Ross Sea region using culture-independent methods. Soil clone libraries were constructed and those clones that occurred > or = 3 times were sequenced. The bacterial diversity of the soils was dependent on the presence of penguins. Firmicutes most closely related to the endospore-formers (e.g., Oceanobacillus profundus and Clostridium acidurici) and (or) Gammaproteobacteria belonging to the genus Psychrobacter dominated soils currently occupied with penguins. In contrast, Gammaproteobacteria, closely related to cultured members of the genera Rhodanobacter, Psychrobacter, Dokdonella, and Lysobacter, dominated the soils previously colonized by penguins. Results of this study indicate that despite relatively high nutrient levels and microbial biomass, bacterial communities of ornithogenic soils were not more diverse than those of mineral soils of the Ross Sea region of Antarctica.

Distal shunt obstruction in children with myelomeningocele after bladder perforation.

PURPOSE: We studied short-term complications and particularly the signs of shunt dysfunction after augmented bladder perforation in patients with myelomeningocele and ventriculoperitoneal shunts. MATERIALS AND METHODS: In our series of bladder augmentations in 27 patients with myelomeningocele and a ventriculoperitoneal shunt in the last 10 years (1994 to 2004) we noted 4 who were 8 to 16 years old at our institute with bladder perforation 2 to 5 years after augmentation. Three patients received a colonic augmentation and 1 received an ileal augmentation. One patient underwent surgery for small bowel obstruction 2 years after the primary operation, when a hole in the augmented bladder was identified and oversewn. The other 3 bladder perforations occurred spontaneously or after failure to catheterize. An additional patient with spontaneous perforation underwent auto-augmentation elsewhere. RESULTS: After primary open abdominal surgery and enterocystoplasty there was no sign of shunt dysfunction in any patient. Bladder perforation and leakage of free urine into the abdominal cavity occurred in 4 of the 5 patients. In those patients severe symptoms of shunt dysfunction, including headache and high intracranial pressure, were noted 2 to 7 days after perforation. In patient 1 there was only urine leakage into a small cavity close to the bladder and no acute signs of post-perforation shunt dysfunction. In all cases the shunt was externalized for 1 to 6 weeks without further complications. CONCLUSIONS: In patients with myelodysplasia who have bladder perforation and free urine in the abdominal cavity the peritoneum is chemically inflamed by urine. Resorption of cerebral liquor may be disturbed, leading to shunt dysfunction and high intracranial pressure. Therefore, it is important for the urologist to recognize and evaluate postoperative signs and symptoms of increased intracerebral pressure in patients with bladder perforation. If found, early computerized tomography of the brain is recommended.

Fetiform teratoma arising from a tubular intestinal duplication. A probable cause of ruptured exomphalos.

A neonate who had a ruptured exomphalos with a fetiform teratoma arising from the end of a long intestinal tubular duplication and a short gut is presented. The management is discussed and the literature is reviewed.

Structural chromosome anomalies in congenital diaphragmatic hernia.

In order to determine the outcome and associated chromosomal and structural anomalies in fetuses diagnosed in utero as having a congenital diaphragmatic hernia, we reviewed 48 consecutive cases referred to our regional Fetal Diagnostic Unit between 1988 and 1995. All babies were delivered in units with appropriate neonatal resuscitation facilities. Thirteen babies [34 per cent of those tested, confidence interval (CI) 19-49 per cent] had karyotypic abnormalities. Three had trisomies but the other nine had more complex karyotypic abnormalities including translocations, deletions, and marker chromosomes. Twenty-one fetuses (44 per cent, CI 30-58 per cent) had additional ultrasound abnormalities which affected the heart in ten cases (21 per cent). Overall, 13 babies survived (27 per cent, CI 14-40 per cent). In babies with normal chromosomes and no additional structural abnormalities the survival rate was 50 per cent (CI 25-75 per cent). Poor outcome was not predicted by early gestation at diagnosis, the hernial contents, or the presence of polyhydramnios. We conclude that parents should be counselled about prognosis with information derived from series of prenatally diagnosed diaphragmatic hernias. The investigations offered should include a detailed ultrasound examination, particularly of the heart, and karyotyping by fetal blood sampling.

Angiostoma schizoglossae n. sp. (Nematoda: Angiostomatidae) from the New Zealand endemic slug Schizoglossa novoseelandica (Gastropoda: Rhytididae).

Angiostoma schizoglossae n. sp. is described from Schizoglossa novoseelandica Pfeiffer collected from a forest in central North Island, New Zealand. Angiostoma schizoglossae is distinguished from other Angiostoma species with peloderan caudal alae in the Northern Hemisphere, by combined characters of subtriangular mouth, lack of lateral alae, and, in the male, variation in position and number of the pedunculate papillae. Its occurrence among the New Zealand endemic land snail fauna extends the known range of the monogeneric Angiostomatidae to include both the Holarctic and Southwest Pacific regions. This is suggestive of the ancient emergence of the Angiostomatidae and their long association with terrestrial molluscs. A key is provided for identification of all known Angiostoma species.

The effects of azidothymidine therapy on pseudocholinesterase concentrations in asymptomatic HIV-positive patients.

The purpose of this study was to determine if a correlation exists between long-term azidothymidine (AZT) therapy and low pseudocholinesterase concentrations in patients who are infected with the human immunodeficiency virus (HIV). A pilot study was conducted of 10 patients infected with HIV, 5 of whom were receiving AZT. Laboratory tests, including complete blood count (CBC), liver function tests, helper/inducer T lymphocyte numbers (CD4), serum dibucaine numbers, and serum pseudocholinesterase concentrations were examined. Control and study subjects both exhibited normal dibucaine numbers, but the pseudocholinesterase concentrations were significantly lower in the group that was not receiving AZT relative to the AZT treatment group. However, only two patients, neither of whom were receiving AZT, demonstrated low or borderline low pseudocholinesterase concentrations according to laboratory criteria. It is possible that pseudocholinesterase synthesis is significantly inhibited by the HIV disease process and that treatment with AZT partly reverses the inhibition. Associated variables contributing to low pseudocholinesterase concentrations in the HIV-positive patient are explored.

Unconjugated faecal bile acids in familial adenomatous polyposis analysed by gas-liquid chromatography and mass spectrometry.

Previous studies have suggested reduced formation of secondary bile acids in patients with familial adenomatous polyposis (FAP). Developments in the collection, extraction and analysis of faecal bile acids as well as in the accurate diagnosis of FAP by DNA markers prompted reinvestigation of this hypothesis. The median (interquartile range (i.q.r.)) faecal bile acid concentration (3.69 (1.66-5.36) mumol per g dry weight) and daily excretion rate (60.5 (29-149) mumol per g per 24 h) in ten patients with FAP were similar to those of nine control subjects (3.31 (0.65-8.38) mumol per g dry weight and 30.1 (7.9-228) mumol per g per 24 h). Although the median (i.q.r.) concentration of only one bile acid (12-oxo-lithocholic acid) was significantly different between patients with FAP and controls (49 (34-70) versus 0 (0-20) nmol per g dry weight, P = 0.006), the derivatives of chenodeoxycholic acid (3.35 (1.76-5.32) versus 0.51 (0.13-2.37) mumol per g dry weight, P = 0.02) and cholic acid (1.63 (0.42-2.34) versus 0.80 (0.13-3.57) mumol per g dry weight, P = 0.006) were increased in those with polyposis. These results show increased bacterial biotransformation of faecal bile acids in patients with FAP.

Biliary bile acid profiles in patients with familial adenomatous polyposis before and after colectomy.

The development of colorectal polyps and cancer in patients with familial adenomatous polyposis (FAP) is directly linked to inactivation of the APC gene. Other, epigenetic, mechanisms may be involved in tumorigenesis and a previous study suggested that an intrinsic difference in the biliary bile acid profile of untreated patients with FAP persisted after colectomy. Gas chromatography and gas chromatography-mass spectrometry were used to examine the biliary bile acid profiles of four groups of patients with normal gallbladders: 20 patients with an intact colon comprising 12 with FAP and eight controls; and 26 patients after colectomy comprising 12 with FAP and 14 controls. Comparison of ten different bile acids from both amidate fractions (glycine and taurine) revealed a small increase in the molar percentage of a minor bile acid (12-oxolithocholic acid) in patients with FAP and an intact colon compared with the matching control group. Colectomy was associated with a dramatic reduction in levels of secondary bile acids but with little difference between patients with FAP and controls.

Analysis of faecal neutral sterols in patients with familial adenomatous polyposis by gas chromatography-mass spectrometry.

Previous studies have suggested that patients with familial adenomatous polyposis (FAP) have increased faecal excretion of cholesterol but a reduction in cholesterol metabolites. It was consequently proposed that the degree of faecal cholesterol degradation could be used as a means of diagnosis. Developments in the extraction and analysis of faecal neutral sterols as well as the accurate means of diagnosing FAP by DNA analysis and indirect ophthalmoscopy has necessitated a re-examination of this proposal. Faecal neutral sterols were analysed in 10 patients with untreated FAP following a complete 5-day stool collection and compared with 9 healthy control subjects (including 4 siblings) closely matched for age and sex. The median [25 and 75, percentiles] stool wet weights were similar between the FAP (97.5 [69, 192] g.24 h-1) and the control (116 [61.5, 137] g.24 h-1) groups. Faecal cholesterol concentration was similar in the two groups (FAP = 2.3 [1.4, 4.2]; control = 3.5 [1.0, 6.0] mumol.g-1 dry wt) as was the concentration of total neutral sterols not including plant sterols (FAP = 17.2 [13.4, 21.0]; control = 18.2 [7.4, 21.6] mumol.g-1 dry wt). There were no significant differences in the proportions of cholesterol metabolised between the FAP (82.3 [74.2, 93.5]%) and control (72.1 [5.7, 81.3]%) groups. This study does not support the notion that faecal neutral sterol metabolism is uniquely different in patients with FAP.