A full genome scan for late onset Alzheimer's disease

We have genotyped 292 affected sibling pairs (ASPs) with Alzheimer's disease (AD) according to NINCDS-ADRDA diagnostic criteria and with onset ages of >/=65 years using 237 microsatellite markers separated by an average distance of 16.3 cM. Data were analysed by SPLINK and MAPMAKER/SIBS on the whole sample of 292 ASPs and subsets of 162 ASPs where both members possessed an apolipoprotein E (APOE)straightepsilon4 allele and 63 pairs where neither possessed anstraightepsilon4 allele. Sixteen peaks with a multipoint lod score (MLS) >1 either in the whole sample, the straightepsilon4-positive or -negative subgroups were observed on chromosomes 1 (two peaks), 2, 5, 6, 9 (two peaks), 10 (two peaks), 12, 13, 14, 19, 21 and X (two peaks). Simulation studies revealed that these findings exceeded those expected by chance, although many are likely to be false positives. The highest lod scores on chromosomes 1 (MLS 2.67), 9 (MLS 2.38), 10 (MLS 2.27) and 19 (MLS 1.79) fulfilLander and Kruglyak's definition of 'suggestive' in that they would be expected to occur by chance once or less per genome scan. Several other peaks were only marginally less significant than this, in particular those on chromosomes 14 (MLS 2.16), 5 (MLS 2.00), 12, close to alpha2-macroglobulin (MLS 1.91), and 21, close to amyloid precursor protein (MLS 1.77). This is the largest genome scan to date in AD and shows for the first time that this is a genetically complex disorder involving several, perhaps many, genes in addition to APOE. Moreover, our data will be of interest to those hoping to identify positional candidate genes using information emerging from neurobiological studies of AD.

Sorption of Eu(III) on attapulgite studied by batch, XPS, and EXAFS techniques

The effects of pH, ionic strength, and temperature on sorption of Eu(III) on attapulgite were investigated in the presence and absence of fulvic acid (FA) and humic acid (HA). The results indicated that the sorption of Eu(III) on attapulgite was strongly dependent on pH and ionic strength, and independent of temperature. In the presence of FA/HA, Eu(III) sorption was enhanced at pH < 4, decreased at pH range of 4-6, and then increased again at pH > 7. The X-ray photoelectron spectroscopy (XPS) analysis suggested that the sorption of Eu(III) might be expressed as is identical to X3Eu0, is identical to S(w)OHEu3+, and is identical to SOEu-OOC-/HA in the ternary Eu/HN/attapulgite system. The extended X-ray absorption fine structure (EXAFS) analysis of Eu-HA complexes indicated that the distances of d(Eu-O) decreased from 2.415 to 2.360 angstroms with increasing pH from 1.76 to 9.50, whereas the coordination number (N) decreased from approximately 9.94 to approximately 8.56. Different complexation species were also found for the different addition sequences of HA and Eu(III) to attapulgite suspension. The results are important to understand the influence of humic substances on Eu(III) behavior in the natural environment.

The growth suppressor PML represses transcription by functionally and physically interacting with histone deacetylases

The growth suppressor promyelocytic leukemia protein (PML) is disrupted by the chromosomal translocation t(15;17) in acute promyelocytic leukemia (APL). PML plays a key role in multiple pathways of apoptosis and regulates cell cycle progression. The present study demonstrates that PML represses transcription by functionally and physically interacting with histone deacetylase (HDAC). Transcriptional repression mediated by PML can be inhibited by trichostatin A, a specific inhibitor of HDAC. PML coimmunoprecipitates a significant level of HDAC activity in several cell lines. PML is associated with HDAC in vivo and directly interacts with HDAC in vitro. The fusion protein PML-RARalpha encoded by the t(15;17) breakpoint interacts with HDAC poorly. PML interacts with all three isoforms of HDAC through specific domains, and its expression deacetylates histone H3 in vivo. Together, the results of our study show that PML modulates histone deacetylation and that loss of this function in APL alters chromatin remodeling and gene expression. This event may contribute to the development of leukemia.

Sodium/proton antiporter in the euryhaline crab Carcinus maenas: molecular cloning, expression and tissue distribution

Gill epithelial cells of euryhaline crustaceans demonstrate net inward transport of sodium ions, possibly via apical Na+/H+ antiporters, Na+/K+/2Cl- cotransporters or Na+ channels working in series with the basolateral Na(+) + K(+)-ATPase. We have identified and sequenced the cDNA coding for a crustacean Na+/H+ antiporter, starting with mRNA isolated from gills of the euryhaline green shore crab Carcinus maenas. The complete 2595-base-pair cDNA includes an open reading frame coding for a 673-amino-acid protein. A search of GenBank revealed more than 20 high-scoring matches, all Na+/H+ antiporter sequences from mammalian, amphibian, teleost and nematode species. Injection of Xenopus laevis oocytes with cRNA transcribed from the cloned crab sequence substantially enhanced Na(+)-dependent H+ efflux from the oocytes. Analysis of crab tissue antiporter mRNA levels by semi-quantitative reverse transcription-polymerase chain reaction revealed that posterior and anterior gills of Carcinus maenas expressed this antiporter the most strongly, followed in decreasing order by skeletal muscle, hepatopancreas, hypodermis and heart. Hydropathy and transmembrane alpha-helix analysis suggested a 10-helix membrane-spanning topology of the antiporter protein. It is clear from this study that Carcinus maenas gills vigorously transcribe a gene coding for a Na+/H+ antiporter. Whether these gills also express a gene coding for an epithelial Na+ channel or Na+/K+/2Cl- cotransporter remains to be demonstrated.

Genetic studies on chromosome 12 in late-onset Alzheimer disease

CONTEXT

The only genetic locus universally accepted to be important as a risk factor for late-onset Alzheimer disease (AD) is the apolipoprotein E (APOE) locus on chromosome 19. However, this locus does not account for all the risk in late-onset disease, and a recent report has suggested a second locus on chromosome 12p11-12.

OBJECTIVE

To look for evidence of linkage on chromosome 12 and to test for the presence of the new locus in an independent sample of familial late-onset AD cases.

DESIGN

Retrospective cohort study. As part of a 20-centimorgan genome screen (approximately equal to 200 markers), we tested a series of 18 genetic markers on chromosome 12 and carried out multipoint, nonparametric lod score and exclusion analyses.

SETTING

Clinic populations in the continental United States selected from the National Institute of Mental Health AD Genetics Consortium.

PATIENTS

We selected samples for DNA analysis from affected sibling pairs, 497 subjects from 230 families with 2 or more affected individuals with probable or definite AD with onset ages older than 60 years (mean+/-SD, 75+/-6 years). Within the families, we used the 2 probable or definitely affected individuals. In families with more than 2 such cases available, we used all of them; in families with only 2 such cases in which unaffected individuals were available, we also sampled the oldest unaffected individual and used genotype data from this unaffected individual to check for nonpaternity and genotyping errors.

MAIN OUTCOME MEASURE

Presence of linkage or locus on chromosome 12.

RESULTS

Although linkage analyses confirmed the presence of a genetic susceptibility factor at the APOE locus in these families with late-onset AD, we were unable to confirm the presence of a locus close to the marker D12S1042. A moderate lod score (1.91) was found near D12S98 close to the alpha2-macroglobulin locus in the affected pairs in which both members did not possess an APOE epsilon4 allele.

CONCLUSIONS

APOE remains the only locus established to be a risk factor for late-onset AD. We were unable to confirm that a locus on chromosome 12p11-12 has a major effect on risk for late-onset AD, although an effect smaller than that for APOE cannot be excluded.

DNA polymorphisms and mutations of the tumor necrosis factor-alpha (TNF-alpha) promoter in Langerhans cell histiocytosis (LCH)

Langerhans cell histiocytosis (LCH) is a clonal proliferation of dendritic histiocytes expressing elevated levels of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 (IL-1), and leukemia inhibitory factor (LIF). The cause of the increased cytokine levels is unknown, but DNA sequence changes in promoters could alter expression. The TNF-alpha and IFN-gamma promoter DNA sequences of 12 LCH patients were studied and compared with normal individuals by dideoxy fingerprinting and DNA sequencing. Functional consequences of polymorphic or mutated sequences were assessed by cloning altered and control promoter sequences into a luciferase reporter gene vector. Electrophoretic mobility shifts (EMSA) after binding of nuclear extracts from a macrophage cell line (U-937) by mutated promoters were compared with controls. Five of 12 LCH patients had alterations in the TNF-alpha promoter DNA sequence. None were found in the IFN-gamma gene promoter. Of the 5 with TNF-alpha DNA alterations, 2 were at position -308, which has been described as a G-A polymorphism associated with upregulation of TNF-alpha in some patients with infections or immune-mediated diseases. The polymorphism at -308 but not the other TNF-alpha promoter mutations caused a 3-fold to 7-fold increased production of the luciferase reporter gene. EMSA showed that the -308 mutant promoters bound fewer nuclear proteins than normals. Polymorphisms of the TNF-alpha promoter in LCH patients could increase the production of that cytokine.

Induction of c-jun protooncogene expression by hydrogen peroxide through hydroxyl radical generation and p60SRC tyrosine kinase activation

The mechanisms of signal transduction of c-jun induction by hydrogen peroxide are elucidated in NIH3T3 cells by using trapping agents of hydroxyl free radical or inhibitors of various protein kinases. Pre-treatment of the cell with hydroxyl radical scavenger dimethyl sulfoxide (DMSO) abolishes the H2O2-induced c-jun expression. Hydroxyl radical generation can be detected and quantified in cells treated sequentially with DMSO and H2O2 for 30 min respectively by methane sulfinic acid (MSA) production, especially that from particulate fraction. Induction of c-jun by H2O2 is also dramatically reduced by pretreating the cells with biological antioxidant vit. E. Protein tyrosine kinase activity of membrane fraction is induced by H2O2 within 5 to 10 min, which can be prevented by DMSO pre-treatment. Inhibitor of non-receptor type tyrosine kinase, herbimycin A, has inhibitory effect on H2O2-induced c-jun expression while the inhibitor of receptor type tyrosine kinase, tyrphostin 23 or inhibitor of cyclic AMP dependent protein kinase, KT 5720, has not. TPA pre-treatment that depletes protein kinase C (PKC) has no influence on the c-jun induction by H2O2. Our results suggest that the highly reactive species HO is generated after H2O2 enter cells and mediate the signal responses of H2O2 including c-jun induction and the activation of p60src tyrosine kinase might be one of the molecular events associated with the c-jun induction pathway.

G-33A mutation in the promoter region of thrombomodulin gene and its association with coronary artery disease and plasma soluble thrombomodulin levels

Thrombomodulin is an endothelial glycoprotein that decreases thrombin activity and activates protein C. A recent study has shown that G-33A promoter mutation of the thrombomodulin gene occurs particularly in Asians. In this study, we analyzed the distribution of G-33A mutation in the promoter region of the thrombomodulin gene in the Chinese population and determined whether the mutation might be a risk for coronary artery disease (CAD). In addition, the influence of this mutation on plasma soluble thrombomodulin levels in patients with CAD was also examined. We studied 320 consecutive patients (mean age 63 years; 73% men) with CAD and 200 age- and sex-matched control subjects. Screening for thrombomodulin G-33A promoter mutation was conducted using polymerase chain reaction, single-strand conformation polymorphism, and direct deoxyribonucleic acid sequencing. The frequency of the G-33A mutation (GA+AA genotypes) was significantly higher in the CAD group (23.8% vs 15.5%, odds ratio [OR] 1.70, p = 0.031). Multiple logistic regression analysis showed that the mutation was an independent risk factor (OR 1.81, p = 0.016) for CAD, as was hypertension (OR 1.44, p = 0.040), diabetes mellitus (OR 2.50, p <0.001), and smoking (OR 2.15, p <0.001). In CAD patients with GG genotype, the soluble thrombomodulin level increased with the extent of CAD (36 +/- 15 vs 47 +/- 18 vs 55 +/- 36 ng/ml in 1-, 2-, or 3-vessel CAD, p <0.001). However, in CAD patients with G-33A mutation, there was no difference between the levels of soluble thrombomodulin (39 +/- 17 vs 37 +/- 15 vs 42 +/- 18 ng/ml, p = NS) in 1-, 2-, or 3-vessel CAD. Our observations suggest that there is a significant association of the G-33A mutation in thrombomodulin gene with CAD, and this mutation may influence the soluble thrombomodulin levels in patients with CAD.

Qualitative determination of urinary morphine by capillary zone electrophoresis and ion trap mass spectrometry

A rapid, sensitive method for the determination of morphine and amphetamine was developed using capillary zone electrophoresis coupled with electrospray interface (ESI), ion-trap tandem mass spectrometry (CE-ESI-MS2). Morphine and amphetamine were separated in 20 mM ammonium acetate buffer (pH 6.6) and detected by ion-trap mass detector in different analytical time segments (0-6.25 min for amphetamine and 6.25-12.0 min for morphine) in which the tune file for each compound was used separately. Molecular ions of morphine (m/z 286) and amphetamine (m/z 136) were detected at 5.77 and 6.83 min, respectively, while product ions of MS2 for each compound (m/z 229, 201 for morphine and m/z 119 for amphetamine) were detected almost exactly at the same time with their parent compounds. The limits of detection (LOD) for MS2 determination were 30 and 50 ng/mL for amphetamine and morphine, respectively, with an S/N ratio of 3. For more sensitive detection of morphine, the sample was injected for a longer time (i.e., 80 s) and hydrodynamically transported into a CE capillary for MS detection. Morphine and its product ion appear at 0.36 and 0.39 min on the ion chromatogram, respectively, with a five-fold increase of detection sensitivity (LOD, 10 ng/mL). The CE-MS system thus established was further applied for forensic urine samples screened as morphine-positive by fluorescence polarization immunoassay (FPIA). These results indicated the feasibility of CE-ESI-MS2 for confirmative testing of morphine in urine sample.

Involvement of p-15(INK4b) and p-16(INK4a) gene expression in saikosaponin a and TPA-induced growth inhibition of HepG2 cells

Saikosaponin a, a purified ingredient of Chinese herb with known antitumor activity, can inhibit cell growth and DNA synthesis of hepatoma cell line HepG2. Both mRNA and protein of the CDK inhibitor p-16(INK4a) and p-15(INK4b) in HepG2 were greatly induced by saikosaponin a while that of p-21(CIP), p-27(KIP) and other cell cycle related genes were not. In addition, reduced phosphorylation of RB protein is observed in saikosaponin a-treated HepG2. Staurosporin, one of the PKC inhibitors, significantly prevented the saikosaponin a induced growth inhibition suggesting PKC pathway be involved. On the other hand, the phorbol ester tumor promoter TPA (12-O-Tetredecanolyphorbol 13-acetate) also inhibited HepG2 growth and specifically induced p-16(INK4a) and p-15(INK4b) mRNA expression. The results suggest that both saikosaponin a and TPA-induced HepG2 growth inhibition are associated with p-15(INK4a) and p-16(INK4b) gene expression and might be mediated by PKC signaling pathway.

[Investigation and analysis on characteristics of a cluster of COVID-19 associated with exposure in a department store in Tianjin]

Objective: To describe the epidemiological characteristics of a cluster of COVID-19 cases reported in Baodi district of Tianjin as of 18 February, 2020, which might be associated with the exposure in a local department store, and provide suggestions for prevention and control strategy development. Methods: The basic characteristics, time and area distributions, clinical manifestations, epidemiological history and transmission mode of the COVID-19 cases associated with the department store exposure were analyzed. Results: A total of 40 COVID-19 cases were associated with the department store exposure, accounting for 75.47% of the total confirmed cases (53 cases) reported in Baodi district. The cases were mainly at the age of 60 years or older (35.00%) and farmers (40.00%). The main clinical manifestations included fever (95.00%), cough (35.00%), and diarrhea (15.00%). The proportion of confirmed severe cases was 32.50%. The incidence curve showed that the incidence peak occurred on 31 January, 2020. Among the 40 cases, 6(15.00%) were department store employees, 19 (47.50%) were customers and 15 (37.50%) were close contacts (secondary cases). The first case occurred on 21 January, 2020, this case was a department store employee who had a purchasing history at whole sale markets in other provinces and cities before the onset, and 3 employees were still on duty after symptom onsets. The median of the incubation period of customer cases was 6 days, and the median of the interval between onset and medical treatment of customer cases was 7 days. Conclusion: This was a cluster epidemic of COVID-19, which might be associated with the exposure in the department store. By now, the current prevention and control measures have achieved satisfied effects.

Comparative in vitro and in vivo activities of two 9-deazaguanine analog inhibitors of purine nucleoside phosphorylase, CI-972 and PD 141955

An in-parallel comparison is presented of the in vitro and in vivo properties of two 9-deazaguanine analog inhibitors of purine nucleoside phosphorylase (PNP), CI-972 [8-amino-9-deaza-9-(3-thienylmethyl)guanine] and PD 141955 [9-deaza-9-(3-thienylmethyl)guanine] (published Ki values of 0.83-8.0 and 0.08 microM, respectively). Despite structural similarities, PD 141955 was considerably more potent and active in all systems studied. The respective IC50 values for inhibition of MOLT-4 cell growth in the absence and presence of 10 microM 2'-deoxyguanosine (GdR) were greater than 50 and 5.06 microM for CI-972 and 15.4 and 0.061 microM for PD 141955. PD 141955 induced accumulation of dGTP in GdR-treated MOLT-4 and CEM cells at log-lower concentrations than were required of CI-972, and the magnitude of dGTP accumulation in PD 141955-treated T cell cultures was markedly greater (e.g. 366 vs 100 pmol/10(6) CEM cells at 10 microM). PD 141955 administered orally produced a dose-dependent elevation of plasma inosine and guanosine in rats over a broad concentration range. Mean plasma inosine concentrations following a 150 mg/kg p.o. dose peaked at 6.21 and 13.2 microM in CI-972 and PD 141955-treated rats, respectively. Low levels of inosine were detectable at 50 micrograms/kg following oral administration of PD 141955.

Bortezomib enhances radiosensitivity in oral cancer through inducing autophagy-mediated TRAF6 oncoprotein degradation

Background

Oral squamous cell carcinoma (OSCC) is a malignant tumor that may occur anywhere within the oral cavity. The survival rate of OSCC patients has not improved over the past decades due to its heterogeneous etiology, genetic aberrations, and treatment outcomes. We investigated the role of tumor necrosis factor receptor-associated factor 6 (TRAF6) in OSCC cells treated with bortezomib (a proteasome inhibitor) combined with irradiation (IR) treatment.

Methods

The effects of combined treatment in OSCC cells were investigated using assays of cell viability, autophagy, apoptosis, western blotting, and immunofluorescence staining. The ubiquitination of proteins was analyzed by immunoprecipitation. Stable knockdown of TRAF6 in OSCC cells was constructed with lentivirus. The xenograft murine models were used to observe tumor growth.

Results

We found synergistic effects of bortezomib and IR on the viability of human oral cancer cells. The combination of bortezomib and IR treatment induced autophagic cell death. Furthermore, bortezomib inhibited IR-induced TRAF6 ubiquitination and inhibited TRAF6-mediated Akt activation. Bortezomib reduced TRAF6 protein expression through autophagy-mediated lysosomal degradation. TRAF6 played an oncogenic role in tumorigenesis of human oral cancer cells and oral tumor growth was suppressed by bortezomib and IR treatment. In addition, OSCC patients with expression of TRAF6 showed a trend towards poorer cancer-specific survival when compared with patients without TRAF6 expression.

Conclusions

A combination of a proteasome inhibitor, IR treatment and TRAF6 inhibition could be a novel therapeutic strategy in OSCC.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0760-0) contains supplementary material, which is available to authorized users.

QT interval effects of cisapride in the clinical setting

PURPOSE

The clinical effect of cisapride on QT intervals was prospectively studied.

SUBJECTS

Consecutive adult patients were recruited in whom cisapride was indicated for gastroesophogeal reflux, gastric ulcer, duodenal ulcer, diabetic gastroparesis or chronic constipation refractory to laxatives. Exclusion criteria included disorders and medications affecting cardiac conduction, electrolyte homeostasis, drug clearance and membrane stability.

METHODS

Seventy-five patients were included and followed at 1 to 2 week intervals. Patients took cisapride 5 mg thrice daily for 1 to 4 weeks (lower dose stage), followed by 10 mg thrice daily for another 1 to 4 weeks (higher dose stage). Twelve-lead ECGs were performed before commencing cisapride (group B), at completion of the lower dose stage (group L) and at completion of the higher dose stage (group H).

RESULTS

No patients experienced presyncope or syncope. Seventeen patients failing to comply, and 7 complaining of abdominal discomfort or diarrhea were excluded, leaving 51 participants. Group H's corrected QT interval (QTc) was longer than group B's by 13+/-15 ms (P<0.001), and longer than group L's by 7+/-11 ms (P<0.001). Group L's QTc was longer than group B's by 7+/-21 ms (P<0.05). QT dispersion did not differ significantly among groups. Neither torsade de pointe nor ventricular tachycardia were noted in Holter monitoring of 33 patients during the higher dose stage.

CONCLUSION

cisapride dose-dependently prolongs the QT interval. Further study is needed to examine the arrhythmogenicity of cisapride in higher doses and for longer durations.

Concentration of vascular endothelial growth factor in the subretinal fluid of retinal detachment

The purpose of this study was to investigate the release of vascular endothelial growth factor (VEGF) within the subretinal fluid in eyes with retinal detachment. Subretinal fluid was collected from patients with retinal detachment undergoing surgery for scleral buckling. Serum samples were also collected. The concentration of VEGF in the subretinal fluid and serum was investigated by enzyme-linked immunospecific assay. The average concentration of VEGF in serum samples was 168 +/- 153 pg/ml (mean +/- standard deviation). It was lower than the VEGF concentration in the subretinal fluid (485 +/- 570 pg/ml) in the same 18 patients with retinal detachment (p < 0.05). The average concentration of VEGF was 355 +/- 373 pg/ml in 31 samples of the subretinal fluid collected from simple rhegmatogenous retinal detachment. It was lower than the average concentration of 901 +/- 385 pg/ml in 8 samples of the subretinal fluid from retinal detachment with proliferative vitreoretinopathy (p < 0.05). The results suggest that the relative retinal ischemia in detached retina increases the release of VEGF into the subretinal space. Also, the concentration of VEGF within the subretinal fluid in proliferative vitreoretinopathy was higher than in simple rhegmatogenous retinal detachment.

Acute massive unilateral hydrothorax: a rare complication of chronic peritoneal dialysis

We have described a case of massive unilateral hydrothorax during chronic peritoneal dialysis. The communication between the peritoneal and right pleural cavities was confirmed by injection into the peritoneal cavity of methylene blue, which promptly appeared in the pleural cavities. Peritoneal dialysis was continued, using decreased dialysate and a semisitting position. The possibility of continuing peritoneal dialysis in the patient with acute hydrothorax and in whom hemodialysis may be contraindicated is demonstrated.

The adsorption behavior of U(VI) on granite

The effects of pH, counter ions and temperature on the adsorption of U(VI) on Beishan granite (BsG) were investigated in the presence and absence of fulvic acid (FA) and humic acid (HA). The adsorption edge of U(VI) on BsG suggested that U(VI) adsorption was mainly controlled by ion exchange and outer-sphere complexation at low pH, whereas inner-sphere complex was the dominant adsorption species in the pH range of 4.0-9.0. Above pH 9.0, Na2U2O7 might play an important role in the rise of U(VI) adsorption again. Counter ions such as Cl(-), SO4(2-) and PO4(3-) can provoke U(VI) adsorption on BsG to some extent, which was directly correlated to the complexing ability of U(VI)-ligand. More noticeably, the large enhancement of U(VI) adsorption in the presence of phosphate can be attributed to the ternary complex formation (BsG-PO4-UO2), precipitation ((UO2)3(PO4)2(s)) and secondary phase (Na-autunite). Both FA and HA can slightly increase U(VI) adsorption at low pH, whereas they strongly inhibited U(VI) adsorption at high pH range. Artificial synthesized granite (AsG) prepared in the laboratory is impossible to use as an analogue of natural granite because of the large difference in the adsorption and surface properties.

Autophagy-inducing effect of pterostilbene: A prospective therapeutic/preventive option for skin diseases

Pterostilbene is a naturally occurring analog of resveratrol with many health benefits. These health benefits are associated with its antioxidant activity, anti-inflammatory effects, and chemopreventive effects attributed to its unique structure. The skin cancer chemopreventive potential of pterostilbene is supported by a variety of mechanistic studies confirming the anti-inflammatory effects in skin cancer models. Molecular biological studies have identified that pterostilbene targets pleotropic signaling pathways, including those involved in mitogenesis, cell cycle regulation, and apoptosis. Recently, pterostilbene has been reported to induce autophagy in cancer and normal cells. Through autophagy induction, the inflammatory-related skin diseases can be attenuated. This finding suggests the potential use of pterostilbene in the treatment and prevention of skin disorders via alleviating inflammatory responses by autophagy induction. This review summarizes the protective and therapeutic benefits of pterostilbene in skin diseases from the viewpoint of its antioxidant, anti-inflammatory, and autophagy-inducing effects. Novel underlying mechanisms regarding these effects are discussed. We proposed that pterostilbene, a promising natural product, can be used as a preventive and therapeutic agent for inflammation-related skin disorders through induction of autophagy.

Carcinogenesis of Male Oral Submucous Fibrosis Alters Salivary Microbiomes

Most oral squamous cell carcinoma (OSCC) tumors arise from oral premalignant lesions. Oral submucous fibrosis (OSF), usually occurring in male chewers of betel quid, is a premalignant stromal disease characterized by a high malignant transformation rate and high prevalence. Although a relationship between the inhabited microbiome and carcinogenesis has been proposed, no detailed information regarding the oral microbiome of patients with OSF exists; the changes of the salivary microbiome during cancer formation remain unclear. This study compared the salivary microbiomes of male patients with OSCC and a predisposing OSF background (OSCC-OSF group) and those with OSF only (OSF group). The results of high-throughput sequencing of the bacterial 16S rRNA gene indicated that OSF-related carcinogenesis and smoking status significantly contributed to phylogenetic composition variations in the salivary microbiome, leading to considerable reductions in species richness and phylogenetic diversity. The microbiome profile of OSF-related malignancy was associated with increased microbial stochastic fluctuation, which dominated the salivary microbiome assembly and caused species co-occurrence network collapse. Artificial intelligence selection algorithms consistently identified 5 key species in the OSCC-OSF group: Porphyromonas catoniae, Prevotella multisaccharivorax, Prevotella sp. HMT-300, Mitsuokella sp. HMT-131, and Treponema sp. HMT-927. Robust accuracy in predicting oral carcinogenesis was obtained with our exploratory and validation data sets. In functional analysis, the microbiome of the OSCC-OSF group had greater potential for S-adenosyl-l-methionine and norspermidine synthesis but lower potential for l-ornithine and pyrimidine deoxyribonucleotide synthesis and formaldehyde metabolism. These findings indicated that the salivary microbiome plays important roles in modulating microbial metabolites during oral carcinogenesis. In conclusion, our results provided new insights into salivary microbiome alterations during the malignant transformation of OSF.

Application of tryptamine as a derivatising agent for airborne isocyanate determination. Part 3. Evaluation of total isocyanates analysis by high-performance liquid chromatography with fluorescence and amperometric detection

Determination of total airborne isocyanates using tryptamine as the derivatising agent was investigated. Tryptamine derivatised isocyanates were analysed by reversed-phase high-performance liquid chromatography (HPLC). The column was equipped with dual detectors of fluorescence emission and amperometric oxidation. The characteristics of fluorescence emission and amperometric oxidation of tryptamine were retained even after its reaction with isocyanates. With this unique behaviour, all tryptamine derivatised isocyanates can be quantified using HPLC by employing a single, pure derivative, such as tryptamine derivatised hexamethylene diisocyanate as the calibration standard. This is especially important for analysing polymeric isocyanates when identical calibration standards are not always available. The applicability of this method for air sampling was evaluated by comparison with the established method of Bagon et al. involving 1-(2-methoxyphenyl)piperazine. Simulation of air sampling was performed in a Test Atmosphere Generation System by the vaporisation of toluene diisocyanate. Satisfactory results were obtained, indicating the applicability of this technique for the determination of total airborne isocyanates.

Retinoic acid-induced apoptosis is prevented by serum albumin and enhanced by Lipiodol in human hepatoma Hep3B cells

The effects of retinoic acid (RA) on the cell growth and viability of human hepatoma Hep3B cells were examined. We showed that removal of serum in the presence of RA results in cell death in a dose-dependent manner in human hepatoma Hep3B cells. Time-course cell death analysis showed that RA at a dose of 10 microM induces a rapid (48-72 h) fall in cell viability (>95%). The drug-induced cell death was RA-specific, since three RA analogs (retinol, retinal and retinol acetate) did not show any cytocidal activity at an equimolar dose. Fluorescence microscopy and DNA fragmentation analysis showed that Hep3B cells treated with RA underwent a death process highly reminiscent of apoptosis, with chromatin condensation, nuclear fragmentation and the presence of a 180-200 bp DNA fragment ladder. Additionally, we found that RA-induced apoptosis was reduced by 70-80% when the medium was supplemented with serum albumin (human and bovine) at a concentration of 0.05%. However, a variety of known growth factors were ineffective in preventing RA-induced apoptosis. Preincubating serum and serum albumin with Lipiodol restored the apoptotic effects of RA demonstrated in serum-free systems. These data suggest that the binding of RA by serum albumin may have reduced the bioavailability of RA, restricting its apoptotic effects on Hep3B cells. Blocking RA-albumin interactions with a lipid lymphographic contrast medium (Lipiodol) may improve the bioavailability of RA and significantly enhance its apoptotic effect on human hepatoma Hep3B cells.

Effects of tannic acid on 12-O-tetradecanoylphorbol-13-acetate-induced protein kinase C activation in NIH 3T3 cells

Tannic acid (TA) is a naturally occurring phenol, which has been found to display an antipromotion effect on mouse skin carcinogenesis. In order to explore the molecular mechanism, we have examined the process of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced protein kinase C (PKC) activation, including phorbol ester binding, enzyme translocation, autophosphorylation and substrate phosphorylation, and finally the TPA-stimulated DNA synthesis. In an initial study, we found that TA slightly inhibited [3H]phorbol dibutyrate (PDBu) binding to intact cells, and only 30% reduction of phorbol ester binding was observed at the highest dose of TA (100 microM). Further analysis by Scatchard plot showed that TA reduced the Bmax of [3H]PDBu from 1.3 pmol/10(6) cells to 1.1 pmol/10(6) cells, but the Kd was increased from 24 to 30 nM. Analysis by western blot indicated that TA did not interfere with the TPA-induced PKC translocation, whereas TA effectively blocked the TPA-evoked phosphorylation of the membrane-bound PKC moiety and its 80 kDa substrate in a dose-dependent manner. We also found that pre- or post-treatment with TA both lead to a similar reduction of 80 kDa protein phosphorylation and that the TPA-stimulated DNA synthesis was also inhibited by TA in a dose-dependent manner, suggesting that the blockage of protein phosphorylation by TA was of biological significance. In conclusion, the work presented here demonstrated that the antitumor promoting effect of TA was not mediated by competing for the binding site with phorbol ester or interrupting the PKC translocation, but rather by effectively blocking phosphorylation by membrane-bound PKC, possibly through altering the biophysical properties of the membrane environment.

Analysis of morphine and morphine-3beta-D glucuronide in human urine by capillary zone electrophoresis with minimal sample pretreatment

The presence of two of the metabolites of heroin, free morphine and morphine 3-beta-D-glucuronide (MO3G) in acidified urine samples was simultaneously determined by capillary zone electrophoresis (CZE). In a run buffer containing 50 mM sodium borate and 250 mM boric acid (pH 8.6), free morphine migrates before a group of neutral compounds (peak N) in urine, which move with the velocity of electro-osmotic flow. In contrast, the glucuronidated form is negatively charged and migrates behind peak N. Both analytes can be precisely identified within their respective analytical window by their migration time with respect to peak N. The on-line multi-wavelengths scanning of the peak permits further confirmation. The detection sensitivity of both analytes was increased three-four fold if the samples were introduced with electro-injection as compared with hydrodynamic injection. Limits of detection (LOD) of free and conjugated morphine using electro-injection were 200 ng/mL and 500 ng/mL, respectively, determined at a 3:1 signal to noise ratio. A dramatic increase of free morphine was observed after acid hydrolysis of the urine concomitantly with the decrease of the glucuronidated form. We conclude that CZE is a rapid, simple, sensitive and useful screening technique for detection of heroin metabolites in the urine.