Separation and characterization of silybin, isosilybin, silydianin and silychristin in milk thistle extract by liquid chromatography-electrospray tandem mass spectrometry.

A selective and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method has been developed for the characterization of silymarin in commercially available milk thistle extract. In this study, six main active constituents, including silydianin, silychristin, diastereomers of silybin (silybin A and B) and diastereomers of isosilybin (isosilybin A and B) in silymarin, were completely separated on a YMC ODS-AQ HPLC column using a gradient mobile phase system comprised of ammonium acetate and methanol/water/formic acid. Identification and characterization of the major constituents were based not only on the product ion scan, which provided unique fragmentation information of a selected molecular ion, but also on the specific fragmentation of multiple reaction monitoring (MRM) data, which confirmed the retention times of LC chromatographic peaks.

Effects of a GTP-insensitive mutation of glutamate dehydrogenase on insulin secretion in transgenic mice.

Glutamate dehydrogenase (GDH) plays an important role in insulin secretion as evidenced in children by gain of function mutations of this enzyme that cause a hyperinsulinism-hyperammonemia syndrome (GDH-HI) and sensitize beta-cells to leucine stimulation. GDH transgenic mice were generated to express the human GDH-HI H454Y mutation and human wild-type GDH in islets driven by the rat insulin promoter. H454Y transgene expression was confirmed by increased GDH enzyme activity in islets and decreased sensitivity to GTP inhibition.

Reliability of microbial surrogate Chlorella for determining Cryptosporidium oocysts removal.

The green alga, Chlorella, abundant in water sources and similar in size to the Cryptosporidium oocysts, may be a suitable candidate to evaluate the removal capacities of the waterworks for Cryptosporidium oocysts. The zeta potentials of Cryptosporidium oocysts in different water samples were more negative than Chlorella. Although the hydrophobicities of Chlorella were similar to Cryptosporidium oocysts, the experimental collision efficiencies for Cryptosporidium oocysts were higher than for Chlorella.

The Histone Database: a comprehensive resource for histones and histone fold-containing proteins.

The Histone Database is a curated and searchable collection of full-length sequences and structures of histones and nonhistone proteins containing histone-like folds, compiled from major public databases. Several new histone fold-containing proteins have been identified, including the huntingtin-interacting protein HYPM. Additionally, based on the recent crystal structure of the Son of Sevenless protein, an interpretation of the sequence analysis of the histone fold domain is presented.

Effects of intrahepatic canine islet autotransplantation on the portal vein pressure and liver function.

Currently, the most common method used for human islet transplantation is intrahepatic implantation via the portal vein, which may affect portal vein pressure and liver function. The aim of this study was to investigate the effects of intrahepatic canine islet autotransplantation on portal vein pressure and liver function. After total pancreatectomy was performed in 30 mongrel dogs, islets were isolated and transplanted back into the portal vein of the same dog.

Islet transplantation at subcutaneous and intramuscular sites.

The subcutaneous site is ideal for clinical islet transplantation because it has the advantage of being accessible and can be biopsied when needed. Sadly, the results at subcutaneous sites were disappointing. The reason for this failure is not known, but poor vascularization may play a role.

Effects of insulin sensitizers on islet transplantation.

To solve the problems of islet engraftment, we investigated the effects of insulin sensitizers, metformin and rosiglitazone, on the in vitro and in vivo function of mouse islets. The in vitro study was done by culturing 30 isolated C57BL/6 mouse islets with glucose (100 or 300 mg/dL) or rosiglitazone (4.5 mumol/L) for 2, 4, 8, or 12 hours.

Structural investigation of edible zein films/coatings and directly determining their thickness by FT-Raman spectroscopy.

Near-infrared Fourier transform Raman (FT-Raman) spectroscopy was employed to study the molecular structure of edible zein films/coatings, which were fabricated directly from zein protein. The secondary structure of zein protein was mainly in alpha-helix and remained unaltered during film formation as evidenced by the vibrational modes of amide I at 1656 cm(-1) and amide III at 1274 cm(-1). Raman results indicated that hydrophobic interaction played an important role in the formation of zein film and disulfide bonding might be responsible for the structural stability of zein protein during film formation.

Using the flow cytometry to quantify the Giardia cysts and Cryptosporidium oocysts in water samples.

The flow cytometry (FC) has been used to detect Giardia cysts and Cryptosporidium oocysts quantitatively and instantaneously in this study. The experimental results showed that FC is potential to become a more precise method for the detection of Giardia and Cryptosporidium in water. This study also evaluated the staining efficiencies for three commercial antibodies.

Attenuation of primary nonfunction for syngeneic islet graft using sodium 4-phenylbutyrate.

Sodium 4-phenylbutyrate (4-SPB), an aromatic derivative of butyric acid, was examined to elucidate its effect on islet engraftment in a syngeneic transplantation model using C57BL/6 mice. Diabetic mice that received subrenal implantation of 150 islets on day 0 and oral administration of twice daily 4-SPB (500 mg/kg body weight) on days -2 through 28 displayed a significantly shorter duration of posttransplantation temporary hyperglycemia than diabetic mice that received islets in isotonic sodium chloride solution (NaCl), namely 16 +/- 2 (n = 12) vs 23 +/- 2 days (n = 7; P < .05).

Survival prolongation of microencapsulated allogeneic islet by nanosized nordihydroguaiaretic acid.

Immunoisolation such as alginate-poly-L-lysine-alginate (APA) microencapsulation may protect entrapped islet graft cells from destruction by cellular and humoral immunities, but cannot avoid aggregation of macrophages and fibroblasts around microcapsules, which has been known to cause late dysfunction. Nordihydroguaiaretic acid (NDGA) is a lipoxygenase inhibitor that prevents the activation and chemotaxis of macrophages. In this study, we used the dialysis method without surfactant to prepare poly (DL-lactide-co-glycolide) (PLGA) nanoparticles to entrap NDGA.

A single-dose of cobalt-protoporphyrin protects islet beta cells from glucocorticoid suppression.

This study examined whether treating donor mice with a single-dose of cobalt protoporphyrin (CoPP) could induce heme oxygenase-1 (HO-1) and thus protect islet cells from suppression by high-dose glucocorticoid. Islets were isolated from mice receiving either a single dose of CoPP (20 mg/kg body weight) (CoPP-islets) or isotonic sodium chloride solution (control islets) at 24 hours before isolation. Following incubation in the absence or presence of methylprednisolone (100 and 1000 ng/mL) for 24 hours, glucose-stimulated insulin secretion and insulin content of cultured islets were determined.

Enhancing islet engraftment with rosiglitazone.

To study the role of a peroxisome proliferator-activated receptor agonist, rosiglitazone, on islet engraftment, streptozotocin-induced diabetic C57BL/6 mice were fed daily rosiglitazone (2.4 mg/kg) for 9 and 31 days starting 2 days before transplantation with 75 and 150 syngeneic islets, respectively. After receiving 75 islets and 9 days of rosiglitazone, half of the treated diabetic mice became normoglycemic at 4 weeks, while none were normoglycemic among those mice that did not receive treatment.

Effects of post-treatment with low-dose propofol on inflammatory responses to lipopolysaccharide-induced shock in conscious rats.

1. In the present study, we used a low dose of propofol (5 mg/kg per h) to investigate its effects on the pro-inflammatory cytokines (tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-10) and changes in nitric oxide (NO) following lipopolysaccharide (LPS) for a period of 12 h in conscious rats. 2.

Application of transcriptome analysis to clinical pharmacology studies.

Clinical pharmacology is the investigation of drug effects in humans. This review discusses the basic tenets of clinical pharmacology research, including pharmacokinetic and pharmacodynamic analysis, therapeutic window, and clinical trial design, and the issues that may arise in the application of transcriptome analysis to clinical pharmacology studies. Examples of how transcriptome analysis can be applied to clinical pharmacology research are described, including a model system of endotoxin challenge (in vitro and in vivo), and an example of a cross-over drug study in normal volunteers.

Joubert syndrome is not a cause of classical autism.

A previous report noted a 27% prevalence of autism in Joubert syndrome (JS), raising the question of overlapping etiologies. Family studies have shown that autism is characterized by family loading for a number of specific behavioral and psychiatric disorders and that the sib recurrence risk is around 4%. The purpose of this study is to determine whether children with Joubert and their families show behavioral or genetic characteristics similar to autism.

Photosynthetic plasticity of Phalaenopsis in response to different light environments.

The ability of a plant to dynamically acclimate to different light environments is, in general, genetically determined. Phalaenopsis amabilis is a CAM orchid with heavy self-shading. The aim of this study was to find out how the photosynthetic capacity of its mature lower leaves acclimates to the low light environment, and whether it possessed a potential for reacclimation following transfer of lower leaves to higher irradiance.

A simple and highly efficient cloning method that employs PCR to directly create a fusion between insert and vector.

We have developed a very simple procedure for gene cloning using compound primers. This approach permits the insertion of a DNA fragment in a single step using a PCR-based cloning protocol, which employs annealing rather than ligation to create the recombinant in the plasmid. This method has been tested successfully to clone a Phalaenopsis gene coding for P450.

Cobalt-protoporphyrin treatment enhances murine isoislets engraftment.

To study the effect of treatment with cobalt-protoporphyrin (CoPP) for the induction of the heme oxygenase-1 (HO-1) enzyme on islet engraftment donor mice received either a single intraperitoneal injection of CoPP (20 mg/kg body weight) 1 day prior to islet isolation or this injection plus a 9 day posttransplantation course of Copp. After a single injection of CoPP, the CoPP-induced islets contained higher HO-1 proteins than did the normal islets both at 12 (5.3 +/- 1.

Characteristics and transplantation of the porcine neonatal pancreatic cell clusters isolated from 1- to 3-day-old versus 1-month-old pigs.

Porcine neonatal pancreatic cell clusters (NPCCs) isolated from 1- to 3-day-old pigs (I-A) cured diabetic nude mice within 8 weeks after transplantation. To shorten the latent period between transplantation and reversal of hyperglycemia, we studied NPCCs isolated from 1-month-old pigs (I-B). One- to 3-day-old or 1-month-old pig pancreata were cut into fragments, digested by collagenase, and then studied for islet characteristics.

Cobalt-Protoporphyrin treatment renders islets tolerant to interleukin-1 beta suppression.

This study examined whether treating donor mice with a single dose of cobalt protoporphyrin (CoPP) induced heme oxygenase-1 (HO-1) and protected islet cells from interleukin-1 beta (IL-1 beta) suppression. Islets were isolated from mice receiving a single dose of either CoPP (20 mg/kg of body weight, CoPP islets) or isotonic NaCl solution vehicle (control islets), 24 hours before isolation. Glucose-stimulated insulin secretion (GSIS) and insulin content (IC) of the islets were determined following incubation in the presence versus absence of murine IL-1 beta for 21 or 65 hours.

Isolation and sequencing a genomic DNA encoding for phenylalanine ammonia-lyase from Phalaenopsis.

The enzyme L-phenylalanine ammonia-lyase is universally present in higher plants and it catalyzes the first committed reaction for a central pathway that generates hundreds of different phenylpropanoid metabolites including anthocyanin, the main pigments in flowers. In this study, we have successfully isolated and analyzed a phenylalanine ammonia-lyase gene from Phalaenopsis. The gene spans 3265bp and consists of two exons and one intron and encodes a polypeptide of 703 amino acid residues.

N-acetylcysteine ameliorates lipopolysaccharide-induced organ damage in conscious rats.

Lipopolysaccharide is strongly associated with septic shock, leading to multiple organ failure. It can activate monocytes and macrophages to release proinflammatory mediators such as tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and nitric oxide (NO). The present experiments were designed to induce endotoxin shock by an intravenous injection of Klebsiella pneumoniae lipopolysaccharide (LPS, 10 mg/kg) in conscious rats.

Cloning and expression of a putative cytochrome P450 gene that influences the colour of Phalaenopsis flowers.

Anthocyanins are responsible for reds through blues in flowers. Blue and violet flowers generally contain derivatives of delphinidin, whereas red and pink flowers contain derivatives of cyanidin or pelargonidin. Differences in hydroxylation patterns of these three major classes of anthocyanidins are controlled by the cytochrome P450 enzymes.

Canine islet isolation, cryopreservation, and transplantation to nude mice.

Background: Successful human islet transplantation has led to insulin independence in type 1 diabetes. Dogs constitute an animal model for preclinical studies. We present our recent experience in canine islet isolation, cryopreservation and transplantation.