Spontaneous emulsification induced by nanoparticle surfactants.

Microemulsions, mixtures of oil, water, and surfactant, are thermodynamically stable. Unlike conventional emulsions, microemulsions form spontaneously, have a monodisperse droplet size that can be controlled by adjusting the surfactant concentration, and do not degrade with time. To make microemulsions, a judicious choice of surfactant molecules must be made, which significantly limits their potential use. Nanoparticle surfactants, on the other hand, are a promising alternative because the surface chemistry needed to make them bind to a liquid-liquid interface is both well flexible and understood. Here, we derive a thermodynamic model predicting the conditions in which nanoparticle surfactants drive spontaneous emulsification that agrees quantitatively with experiments using Noria nanoparticles. This new class of microemulsions inherits the mechanical, chemical, and optical properties of the nanoparticles used to form them, leading to novel applications.

Correction: Programmable microfluidic synthesis of spectrally encoded microspheres.

Correction for 'Programmable microfluidic synthesis of spectrally encoded microspheres' by R. E. Gerver et al., Lab Chip, 2012, 12, 4716-4723.

Programmable microfluidic synthesis of spectrally encoded microspheres.

Spectrally encoded fluorescent beads are an attractive platform for assay miniaturization and multiplexing in the biological sciences. Here, we synthesize hydrophilic PEG-acrylate polymer beads encoded with lanthanide nanophosphors using a fully automated microfluidic synthesis device. These beads are encoded by including varying amounts of two lanthanide nanophosphors relative to a third reference nanophosphor to generate 24 distinct ratios. These codes differ by less than 3% from their target values and can be distinguished from each other with an error rate of <0.1%. The encoded bead synthesis strategy we have used is readily extensible to larger numbers of codes, potentially up to millions, providing a new platform technology for assay multiplexing.

Linkage of frontotemporal dementia to chromosome 17: clinical and neuropathological characterization of phenotype.

Frontotemporal dementia is a behavioral disorder of insidious onset and variable progression. Clinically, its early features reflect frontal lobe dysfunction characterized by personality change, deterioration in memory and executive functions, and stereotypical and perseverative behaviors. Pathologically, there is degeneration of the neocortex and subcortical nuclei, without distinctive features such as plaques, neurofibrillary tangles, or Pick or Lewy bodies. Within-family variation in neuropathology and clinical phenotype is observed. In cases where family aggregation is observed, it is inherited as an autosomal dominant, age-dependent disorder. Family studies recently have identified two dementia loci: chromosome 17 for disinhibition-dementia-parkinsonism-amyotrophic complex and pallido-ponto-nigral degeneration and chromosome 3 for familial nonspecific dementia. We describe a family (DUK1684) with clinically and neuropathologically confirmed, autosomal dominant, non-Alzheimer disease dementia. Linkage analysis of this family showed evidence for linkage to chromosome 17q21, with a multipoint location score (log10) of 5.52. A comparison of the clinical and pathological features in DUK1684 with those of the other chromosome 17-linked families, together with the linkage data, suggests that these families are allelic. These studies emphasize that genetic linkage analysis remains a useful tool for differentiating disease loci in clinically complex traits.

Confirmation of linkage of oculopharyngeal muscular dystrophy to chromosome 14q11.2-q13.

Oculopharyngeal muscular dystrophy is a late-onset, autosomally dominant disorder characterized by progressive ptosis, dysphagia, and extremity weakness. Linkage of oculopharyngeal muscular dystrophy to 14q11.2-q13 has been reported in a series of French Canadian families. Haplotype analysis in these data shows a single segregating disease chromosome, suggesting a founder effect in this population. We ascertained and sampled for linkage studies 5 multigenerational American families with oculopharyngeal muscular dystrophy. Four of the 5 families have known French Canadian ancestry while the fifth is of English/Scottish origin. A peak multipoint lod score of 6.30 was obtained for the marker MYH7.1 in the families, confirming linkage to 14q11.2-q13. The English/Scottish family exhibited a different chromosomal haplotype for the oculopharyngeal muscular dystrophy alleles than did the families of French Canadian origin. These data suggest that this family may represent a second, possibly independent mutation in this disorder.

Laparoscopic cholecystectomy in a young girl.

Laparoscopic cholecystectomy is now a widely used procedure in adults. However, reports on this procedure in infants and young children are rare. This paper reports a successful laparoscopic cholecystectomy in a young girl.

Laparoscopic proximal gastric vagotomy--neuralgic points of technique.

Laparoscopic proximal gastric vagotomy is a valuable therapeutic tool in the management of patients suffering from recurrent duodenal ulcer disease, the therapeutic principle being the effective reduction of gastric acid output without gastrotomy or gastric resection. The method is based on the well-documented conventional technique, which has been evaluated for over 15 years. The division of all vagal fibres to the gastric fundus and body is essential for complete vagotomy in order to ensure a sufficient reduction in gastric acid. The operation time is between 2 and 3 hours. Eighteen patients have been treated successfully with this minimally invasive and safe procedure in our unit. The functional and cosmetic results are excellent. The comparatively lower costs are, last but not least, an important advantage.

Strategy and technique of laparoscopic common bile duct exploration.

The laparoscopic approach to common bile duct exploration enables the complete clearance of stones from the bile duct without damage to structures of physiological importance such as the ampulla of Vater. Despite preoperative endoscopic retrograde cannulation of the biliary tree (ERCP) in patients with suspected stones, routine intraoperative cholangiography reveals a further 6% with unsuspected common bile duct stones. Both the preoperative suspected stone and the stone found on intraoperative cholangiography can be adequately managed by the laparoscopic method. The approach to the common bile duct via the cystic duct avoids incising the common duct or the sphincter of Oddi. The common bile duct can be approached satisfactorily by balloon dilatation of the cystic duct to 5 mm so enabling the choledochoscope to be inserted into the common bile duct. Small stones are washed into the duodenum or extracted by the Segura basket retrogradely through the cystic duct. Larger stones can be disintegrated by laser or electrohydraulic lithotripsy; the fragments can either be washed into the duodenum or sucked out via the cystic duct. Laparoscopic choledochotomy is indicated for multiple big or proximally located stones. The larger sized Segura basket can be used effectively for these large stones. Residual stones are extracted under cholangioscopic control and any incarcerated stone disintegrated by lithotripsy. A small catheter placed in the common bile duct or a standard T-tube completes the exploration and avoids disordered function of the sphincter of Oddi.(ABSTRACT TRUNCATED AT 250 WORDS)

[Laparoscopic operations of the bile duct]. / Laparoskopische Operationen am Gallengang.

Laparoscopic common bile duct exploration offers the possibility of complete minimal invasive therapy of biliary stone disease with respect to the anatomical structures of the papilla Vateri. In spite of generously indicated preoperative ERC, we found in 23 of 376 laparoscopic cholecystectomies unsuspected common bile duct stones by intraoperative in principle cholangiography. 8 patients with known common bile duct stones got a complete laparoscopic therapy. Balloon-dilatation of the ductus cysticus up to 5 mm is followed by laparoscopic choledochoscopy via the cystic duct. Small stones are washed into the duodenum or extraced retrogradely via the cystic duct. For bigger stones the intracorporeal lithotripsy is available, the stone scrap is washed either into the duodenum or is sucked off via the cystic duct. Laparoscopic choledochotomy is indicated for multiple big or proximally fixed stones. In this way stone extraction can be effectively performed, incarcerated stones are treated by additional lithotripsy. A microdrainage of the common bile duct or a T-tube drainage secures the bile flow until restitution of papillary function. The common bile duct is sewn by running suture. In the case of regular cholangiography the microdrainage can be removed on the third postoperative day. In 96% of the laparoscopic cholecystectomies intraoperative cholangiography was possible. 3 of 21 patients with transductus cysticus-exploration had to undergo postoperative EPT due to residual stone fragments. 6 laparoscopic choledochotomies showed the efficacy of the endoscopic operation technique, demonstrating the probability of complications in the postoperative period to be equivalent to that of conventional operations.(ABSTRACT TRUNCATED AT 250 WORDS)

Uptake and phosphorylation of phosphatidylinositol by rat liver nuclei. Role of phosphatidylinositol transfer protein.

The incorporation of phosphatidyl[2-3H]inositol ([3H]PI) from vesicles or microsomal membranes into rat liver nuclei is greatly stimulated by phosphatidylinositol transfer protein (PI-TP). The nuclei are able to phosphorylate [3H]PI, with the production of phosphatidylinositol 4-phosphate (PIP). Recovery of tritiated inositol trisphosphate, inositol phosphate, glycerophosphoinositol and inositol, suggests that in isolated nuclei a large set of enzymes of the PI cycle is present, similar to the enzymes involved in the plasma membrane PI cycle. Incubation with [gamma-32P]ATP shows that isolated nuclei are able to phosphorylate endogenous PI to PIP and phosphatidylinositol 4,5-bisphosphate (PIP2). In the presence of exogenous PI and detergent the synthesis of PIP is increased, indicating that in nuclei the PI pool is suboptimal for the PI-kinase activity. The present study suggests that PI-TP may be involved in providing substrates for PI metabolism at the nuclear level.