Using machine learning to identify proteomic and metabolomic signatures of stroke in atrial fibrillation

Atrial fibrillation (AF) is a common cardiac arrhythmia, with stroke being its most detrimental comorbidity. The exact mechanism of AF related stroke (AFS) still needs to be explored. In this study, we integrated proteomics and metabolomics platform to explore disordered plasma proteins and metabolites between AF patients and AFS patients. There were 22 up-regulated and 31 down-regulated differentially expressed proteins (DEPs) in AFS plasma samples. Moreover, 63 up-regulated and 51 down-regulated differentially expressed metabolites (DEMs) were discovered in AFS plasma samples. We integrated proteomics and metabolomics based on the topological interactions of DEPs and DEMs, which yielded revealed several related pathways such as arachidonic acid metabolism, serotonergic synapse, purine metabolism, tyrosine metabolism and steroid hormone biosynthesis. We then performed a machine learning model to identify potential biomarkers of stroke in AF. Finally, we selected 6 proteins and 6 metabolites as candidate biomarkers for predicting stroke in AF by random forest, the area under the curve being 0.976. In conclusion, this study provides new perspectives for understanding the progressive mechanisms of AF related stroke and discovering innovative biomarkers for determining the prognosis of stroke in AF.

[Longitudinal correlation between cell phone use and sleep quality in college students]

Objective: To investigate the current situation of cell phone use and sleep quality among college students, establish a sleep quality trajectory model and explore the influence of cell phone use on the sleep quality trajectory. Methods: Based on data from the College Student Behavior and Health Cohort Study 2019-2020, a latent class growth modeling was used to establish a sleep quality trajectory model among college students. The baseline influencing factors of sleep quality trajectories among college students were analyzed by χ² test, and the effects of cell phone use on sleep quality trajectories were analyzed by binary logistic regression. Results: A total of 1 092 college students were included in the analysis. The detection rates of cell phone use and poor sleep quality were 24.5% and 13.3%. Latent class growth model identified two groups of sleep quality trend trajactories: an improved sleep quality group (86.0%) and a decreased sleep quality group (14.0%). The result of binary logistic regression showed that the cell phone use was a risk factor of sleep quality trajectories. Conclusion: The cell phone use during college period could increase the risk of poor sleep quality. Targeted intervention measures about cell phone use should be adopted to improve the sleep quality among college students.

Absolute calibration of Fujifilm BAS-TR image plate response to laser driven protons up to 40 MeV

Image plates (IPs) are a popular detector in the field of laser driven ion acceleration, owing to their high dynamic range and reusability. An absolute calibration of these detectors to laser-driven protons in the routinely produced tens of MeV energy range is, therefore, essential. In this paper, the response of Fujifilm BAS-TR IPs to 1-40 MeV protons is calibrated by employing the detectors in high resolution Thomson parabola spectrometers in conjunction with a CR-39 nuclear track detector to determine absolute proton numbers. While CR-39 was placed in front of the image plate for lower energy protons, it was placed behind the image plate for energies above 10 MeV using suitable metal filters sandwiched between the image plate and CR-39 to select specific energies. The measured response agrees well with previously reported calibrations as well as standard models of IP response, providing, for the first time, an absolute calibration over a large range of proton energies of relevance to current experiments.

Calibration of BAS-TR image plate response to GeV gold ions

The response of the BAS-TR image plate (IP) was absolutely calibrated using a CR-39 track detector for high linear energy transfer Au ions up to ∼1.6 GeV (8.2 MeV/nucleon), accelerated by high-power lasers. The calibration was carried out by employing a high-resolution Thomson parabola spectrometer, which allowed resolving Au ions with closely spaced ionization states up to 58⁺. A response function was obtained by fitting the photo-stimulated luminescence per Au ion for different ion energies, which is broadly in agreement with that expected from ion stopping in the active layer of the IP. This calibration would allow quantifying the ion energy spectra for high energy Au ions, which is important for further investigation of the laser-based acceleration of heavy ion beams.

The efficacy and safety of menatetrenone in the management of osteoporosis: a systematic review and meta-analysis of randomized controlled trials

In our systematic review and meta-analysis, we comprehensively evaluated menatetrenone in the management of osteoporosis. We found that menatetrenone decreased the ratio of undercarboxylated osteocalcin to osteocalcin (ucOC/OC) and improved lumbar BMD compared with placebo based on the 18 studies assessed. However, its benefit in fracture risk control was uncertain.

INTRODUCTION

We performed a systematic review and meta-analysis of the efficacy and safety of menatetrenone in managing osteoporosis.

METHODS

PubMed, Cochrane Library, Embase, ClinicalTrials.gov , and three Chinese literature databases (CNKI, CBM, Wanfang) were searched for relevant randomized controlled trials (RCTs) published before October 5, 2017, comparing menatetrenone with other anti-osteoporotic drugs or placebo in treating osteoporosis. The pooled risk ratio (RR) or mean difference (MD) and 95% confidence interval (CI) were calculated using fixed-effects or random-effects meta-analysis.

RESULTS

Eighteen RCTs (8882 patients) were included. Pooled analyses showed that menatetrenone was more effective than placebo in improving lumbar bone mineral density (BMD) (five studies, N = 658, MD = 0.05 g/cm², 95% CI 0.01 to 0.09 g/cm²) and decreasing ucOC/OC (two studies, N = 75, MD = - 21.78%, 95% CI - 33.68 to - 9.87%). Compared with placebo, menatetrenone was associated with a nonsignificantly decreased risk of vertebral fracture (five studies, N = 5508, RR = 0.87, 95% CI 0.64 to 1.20). Evidence on other anti-osteoporotic drugs as comparators was limited and revealed no significantly different effects of menatetrenone on BMD or fracture risks. Furthermore, compared with placebo, menatetrenone significantly increased the incidence of adverse events (AEs) (two studies, N = 1949, RR = 1.47, 95% CI 1.07 to 2.02) and adverse drug reactions (four studies, N = 6102, RR = 1.29, 95% CI 1.07 to 1.56). However, no significant difference in the incidence of serious AEs was found between menatetrenone and placebo.

CONCLUSIONS

Menatetrenone significantly decreases ucOC and might improve lumbar BMD in osteoporotic patients. However, its benefit in fracture risk control is uncertain.

A Feasibility Study of a New Unibody Branched Stent Graft Applied to Reconstruct the Canine Aortic Arch

OBJECTIVES

The aim was to evaluate the feasibility and safety of a new unibody branched stent graft for the reconstruction of the canine aortic arch.

METHODS

The unibody branched stent grafts included single branched stent grafts and double branched stent grafts. The main stent graft and branched limbs were sutured together. The branched stent grafts were folded into the introducer system, which consisted of a double channel catheter, a detachable sleeve, and an introducer sheath. The branched stent grafts were introduced and deployed into the aortic arch by the delivery system. Twenty adult mongrel dogs were used for the experiments. Ten dogs were implanted with single branched stent grafts; the other 10 were implanted with double branched stent grafts. The surviving animals were followed up for 3 months. Computed tomography angiography (CTA) was performed to observe the status of the branched stent grafts.

RESULTS

All the unibody branched stent grafts were successfully implanted into the canine aortic arches. The technical success rate was 100%. There was no cerebral infarction, paraplegia or incision infection. CTA showed that all the branched stent grafts were patent; there was no endoleak or stent migration.

CONCLUSIONS

The unibody branched stent graft system could be used to reconstruct the aortic arch. The animal experimental procedures demonstrated the safety and feasibility of the unibody branched stent graft system.

Dipeptidyl peptidase-4 inhibitors and risk of arthralgia: A systematic review and meta-analysis

BACKGROUND

The US Food and Drug Administration has warned that treatment with dipeptidyl peptidase (DPP)-4 inhibitors may promote serious arthralgia. However, the clinical evidence for this is relatively lacking.

OBJECTIVE

For this reason, a systematic review and meta-analysis of randomized controlled trials (RCTs) were carried out to determine the relationship between DPP-4 inhibitors and risk of arthralgia, and also to investigate any potential risk factors.

METHODS

An extensive electronic search for RCTs comparing DPP-4 inhibitors with any comparators was performed up to July 2016. Outcomes of interest were overall and serious arthralgia. Summary risk ratios (RRs) with 95% confidence intervals (CIs) were calculated.

RESULTS

A total of 67 RCTs (involving 79,110 patients) was ultimately included. Pooled results showed that DPP-4 inhibitors were associated with a slightly but significantly increased risk of overall arthralgia (RR: 1.13, 95% CI: 1.04-1.22; P=0.003) and a non-significant increased risk of serious arthralgia (RR: 1.44, 95% CI: 0.83-2.51; P=0.20). Also, subgroup analyses showed that add-on/combination therapy and longer diabetes duration (>5years) were possible factors associated with the increased risk of overall arthralgia.

CONCLUSION

These findings suggest that DPP-4 inhibitors can increase the risk of arthralgia. Thus, the benefits of glycaemic control must be weighed against the risk of arthralgia when prescribing DPP-4 inhibitors. Further studies are now needed to identify and confirm these risk factors.

Comparative efficacy of bisphosphonates in short-term fracture prevention for primary osteoporosis: a systematic review with network meta-analyses

Our network meta-analyses compared the efficacy of different bisphosphonates preventing fractures for primary osteoporosis. By including 36 studies, we found that zoledronic acid seemed the most effective in preventing vertebral fracture, nonvertebral fracture, and any fracture, and alendronate or zoledronic acid seemed the most effective in preventing hip fracture.

INTRODUCTION

This study was conducted in order to analyze the available evidence on the efficacy of bisphosphonates for preventing fractures.

METHODS

We considered randomized trials comparing any bisphosphonate with other bisphosphonate or placebo. We searched Cochrane Library, Embase, and PubMed and manually searched reference list of relevant articles. Pairwise and network meta-analyses were performed. The primary outcome is vertebral fracture. Secondary outcomes include nonvertebral fracture, hip fracture, wrist fracture, and any fracture.

RESULTS

Thirty-six studies were included. Significant difference was found between bisphosphonates for vertebral fracture and nonvertebral fracture (P < 0.0001 and P = 0.04, respectively). Compared with placebo, alendronate, clodronate, ibandronate, minodronate, pamidronate, risedronate, and zoledronic acid significantly prevented vertebral fracture. Zoledronic acid significantly reduced the risk of vertebral fracture, compared with alendronate, clodronate, etidronate, ibandronate, risedronate, and tiludronate (0.65 (0.46, 0.91), 0.53 (0.33, 0.86), 0.45 (0.27, 0.74), 0.52 (0.36, 0.75), 0.59 (0.42, 0.83), and 0.31 (0.21, 0.48), respectively). Compared with etidronate, clodronate and zoledronic acid significantly prevented nonvertebral fracture. Compared with alendronate, zoledronic acid significantly prevented any fracture. The possibility rankings showed that zoledronic ranked first in preventing vertebral fracture, hip fracture, and any fracture, and pamidronate ranked first in preventing nonvertebral fracture and wrist fracture. In the sensitivity analyses, zoledronic acid ranked first in preventing nonvertebral fracture, and alendronate ranked first in preventing hip fracture and wrist fracture.

CONCLUSION

Zoledronic acid seemed the most effective in preventing vertebral fracture, nonvertebral fracture, and any fracture, and alendronate or zoledronic acid seemed the most effective in preventing hip fracture. Uncertainty still remains and future studies are needed to accurately evaluate the comparative efficacy of bisphosphonates.

Influence of arginine on the growth, arginine metabolism and amino acid consumption profiles of Streptococcus thermophilus T1C2 in controlled pH batch fermentations

AIMS

The aim of this study was to elucidate the effect of arginine on the growth, arginine metabolism and amino acid consumption profiles of Streptococcus thermophilus T1C2.

METHODS AND RESULTS

The growth kinetics, intracellular pH, extracellular osmotic pressure, expression of key genes in the arginine metabolism pathway and amino acid consumption profiles were analysed in chemically defined medium with different initial arginine concentrations. The results showed that arginine stimulated the growth of Strep. thermophilus T1C2 under low intracellular pH and high extracellular osmotic pressure. The expression of key genes in the arginine degradation pathway indicated that arginine relieved the drop in the intracellular pH by consuming protons and generating NH3 . Additionally, the results showed that arginine degradation did not occur via the arginine deiminase pathway but through the arginine decarboxylase-urease pathway. Furthermore, the utilization efficiency of amino acids was improved in the presence of arginine.

CONCLUSIONS

Arginine improved the growth of Strep. thermophilus due to protecting Strep. thermophilus against intracellular acid stress, which was revealed at the transcriptional level of key genes. This study showed that the acid resistance of Strep. thermophilus was achieved through the arginine decarboxylase-urease pathway.

SIGNIFICANCE AND IMPACT OF THE STUDY

The arginine-stimulated growth of Strep. thermophilus improved the utilization efficiency of amino acids and reduced nitrogen waste, which could be useful for the optimization of cultivation media.

Pharmacokinetic and Pharmacodynamic Drug Interaction Study of Piragliatin, a Glucokinase Activator, and Glyburide, a Sulfonylurea, in Type 2 Diabetic Patients

A glucokinase activator and a sulfonylurea might be coprescribed to synergize treatment success for type 2 diabetes (T2D). This clinical pharmacology study was designed to investigate the potential glucose-lowering effect or pharmacodynamic (PD), pharmacokinetic (PK), and safety/tolerability interactions between piragliatin and glyburide in T2D patients already taking glyburide but not adequately controlled. This was an open-label, multiple-dose, 3-period, single-sequence crossover design: on days -1, 6, and 12, PD and PK samples were drawn with glyburide alone (period 0), piragliatin + glyburide (period 1), and piragliatin alone (period 2) treatments. The glucose-lowering effect, including fasting plasma glucose (FPG), of piragliatin was more pronounced when it was administered concomitantly with glyburide as compared to piragliatin or glyburide administered alone. However, this enhancement cannot be explained by a potential PK interaction between piragliatin and glyburide. Other than hypoglycemia, there were no clinically relevant safety findings. Thus, the enhanced PD effect warrants further investigation to define the optimal dose combination between glucokinase activators and sulfonylureas with regard to efficacy, safety, and tolerability.

Long-term efficacy of endovascular vs open surgical repair for complicated type-B aortic dissection: a single-center retrospective study and meta-analysis

This study aimed to evaluate the long-term survival and risk factors of traditional open surgical repair (OSR) vs thoracic endovascular aneurysm repair (TEVAR) for complicated type-B aortic dissection (TBAD). A total of 118 inpatients (45 OSR vs 73 TEVAR) with TBAD were enrolled from January 2004 to January 2015. Kaplan-Meier curves and Cox proportional hazards analysis were performed to identify the long-term survival rate and independent predictors of survival, respectively. Meta-analysis was used to further explore the long-term efficacy of OSR and TEVAR in the eight included studies using Review Manager 5.2 software. An overall 10-year survival rate of 41.9% was found, and it was similar in the two groups (56.7% OSR vs 26.1% TEVAR; log-rank P=0.953). The risk factors of long-term survival were refractory hypertension (OR=11.1; 95%CI=1.428-86.372; P=0.021] and preoperative aortic diameter >55 mm (OR=4.5; 95%CI=1.842-11.346; P=0.001). Long-term survival rate did not differ significantly between OSR and TEVAR (hazard ratio=0.87; 95%CI=0.52-1.47; P=0.61). Compared with OSR, TEVAR did not show long-term advantages for patients with TBAD. Refractory hypertension and total aortic diameter >55 mm can be used to predict the long-term survival of TBAD in the Chinese Han population.

From fighting depression to conquering tumors: a novel tricyclic thiazepine compound as a tubulin polymerization inhibitor

A novel tricyclic thiazepine derivative, 6-(p-tolyl)benzo[f] pyrido[2,3-b][1,4] thiazepine 11,11-dioxide (TBPT), exhibits potent inhibitory effects in two non-small-cell lung cancer cell lines, H460 and its drug-resistant variant, H460_TaxR, while exhibiting much less toxic effects on normal human fibroblasts. After five injections of TBPT at a dose of 60 mg/kg, it inhibits H460_TaxR tumor growth in xenografted mouse models by 66.7% without causing observable toxicity to normal tissues. Based on gene perturbation data and a series of investigations, we reveal that TBPT is not a P-glycoprotein substrate and it inhibits microtubule formation by targeting tubulin, thereby causing cell cycle arrest at the G2/M stage and eventually inducing apoptosis. This redeployment of anti-depressant compound scaffold for anticancer applications provides a promising future for conquering drug-resistant tumors with fewer side effects.

Evaluation of autochthonous micrococcus strains as starter cultures for the production of Kedong sufu

AIMS

The technological properties of 22 micrococcus strains from traditional fermented Kedong sufu were evaluated in order to develop autochthonous starter cultures.

METHODS AND RESULTS

The proteolytic, autolytic and lipolytic activity, salt tolerance, production and degradation of the biogenic amines of six Micrococcus luteus, nine Kocuria kristinae and seven Kocuria rosea were evaluated. The results indicated that these micrococcus strains exhibited a certain technological diversity, and the results also indicated the best properties to be used in mixed starter cultures. Based on the above findings, two sets of autochthonous starters were formulated. Considering the physicochemical properties and sensory characteristics of sufu, the maturation period of sufu was shortened by 30 days. The profiles of free amino acids and peptides partly revealed the mechanism of sensory quality and shorter ripening time of sufu manufactured using autochthonous mixed starters. Compared to back-slopping fermentation, sufu manufactured with selected autochthonous starter cultures exhibited lower levels of total biogenic amines.

CONCLUSIONS

The selected strains could be used as starter to avoid the accumulation of high concentrations of biogenic amines while also maintaining typical sensory characteristics and preserving the autochthonous strains of the traditional Kedong sufu. The maturation times of Kedong sufu were shortened by 30 days with application of the autochthonous starter.

SIGNIFICANCE AND IMPACT OF THE STUDY

Autochthonous mixed starters can reduce the generation of biogenic amines, speed up the sufu maturation process and preserve typical sensory quality. Furthermore, the rotation of two sets of mixed starter cultures can effectively resist phage attack during the production of sufu.

Using real-world data to evaluate the association of incretin-based therapies with risk of acute pancreatitis: a meta-analysis of 1,324,515 patients from observational studies

AIM

To investigate the real-world incidence of acute pancreatitis (AP) associated with incretin-based therapy (IBT).

METHODS

We carried out a systematic review and meta-analysis of observational studies using Medline, PubMed, Embase, the Cochrane Database, ClinicalTrials.gov and conference proceedings. We included: those studies in which AP was a pre-defined clinical outcome; longitudinal studies (case-control, cohort); studies that adjusted for confounders; studies that reported on a population exposed to IBT; studies in which non-IBT users or past users (who received IBTs >90 days before the index date) were used as the control group; studies that reported risk estimates [relative risks, odds ratios (ORs) or hazard ratios] with 95% confidence intervals (CIs) for AP event with IBT use, or that reported sufficient data to estimate these; and publications in the English language. Data were extracted by two independent investigators, and a consensus was reached with involvement of a third. Study-specific ORs from seven cohort studies and two case-control studies were meta-analysed using random-effects models. Associations were tested in subgroups representing different patient characteristics and study quality.

RESULTS

A total of nine studies that included 1,324,515 patients and 5195 cases of AP were included in our meta-analysis. The summary estimate of OR for an association between IBT and AP was 1.03 (95% CI 0.87-1.20).

CONCLUSIONS

The present meta-analysis of real-world data does not suggest that IBT is associated with AP. Although we should continue to remain vigilant, IBTs should be regarded as reasonable options to consider adding to the regimen of a patient with type 2 diabetes.

A cyclic peptide that binds p75(NTR) protects neurones from beta amyloid (1-40)-induced cell death

The current study determined the ability of a p75(NTR) antagonistic cyclic peptide to rescue cells from beta amyloid (Abeta) (1-40)-induced death. p75(NTR)-, p140(trkA)-NIH-3T3 cells or E17 foetal rat cortical neurones were incubated with 125I-NGF or 125I-Abeta (1-40) and increasing concentrations of the cyclic peptide (CATDIKGAEC). Peptide ability to displace 125I-NGF or 125I-Abeta (1-40) binding was determined. Duplicate cultures were preincubated with CATDIKGAEC (250 nM) or diluent and then stimulated with Abeta (1-40). Peptide ability to displace Abeta (1-40) binding, interfere with Abeta (1-40)-induced signalling and rescue cells from Abeta-mediated toxicity was determined by immunoprecipitation and autoradiography, Northern blotting, JNK activation, MTT and trypan blue assays. The peptide inhibited NGF and Abeta (1-40) binding to p75(NTR), but not to p140(trkA). Abeta (1-40) induced c-jun transcription (57.3% +/- 0.07%) in diluent-treated p75(NTR)-cells, but not in cells preincubated with the cyclic peptide. Also, at 250 nM, the peptide reduced Abeta (1-40)-induced phosphorylation of JNK by 71.8% +/- 0.03% and protected neurones against Abeta-induced toxicity as determined by: trypan blue exclusion assay (53% +/- 11% trypan blue-positive cells in diluent pretreated cultures vs. 28% +/- 5% in cyclic peptide-pretreated cultures); MTT assay (0.09 +/-0.03 units in diluent-pretreated cells vs. 0.12 +/- 0.004 units in cyclic peptide-pretreated cells); and visualization of representative microscopic fields. Our data suggest that a cyclic peptide homologous to amino acids 28-36 of NGF known to mediate binding to p75(NTR) can interfere with Abeta (1-40) signalling and rescue neurones from Abeta (1-40)-induced toxicity.

[The role of fibrinolysis in pathogenesis of middle ears adhesions]

OBJECTIVE

To investigate the role of fibrinolysis in pathogenesis of middle ears adhesions.

METHODS

The amount of Tissue-type Plasminogen Activator (tPA) of 28 sections from 6 ears with adhesive otitis media (AOM) and of 22 sections from 6 normal ears was examined by Super Sensitive Biotin-Streptavidin (SSBSA) method. Amount of Fibrin of 11 sections from 3 ears with significant adhesions was compared with that of 12 sections from 3 normal ears. Qualitative analysis of light microscopy with computer-assisted image system was employed.

RESULTS

In adhesive ears, tPA stains were negative in 11 of 28 sections and faint positive were 10 of 28 sections, while Fibrin stains were positive in 6 of 11 sections and strong positive were in 3 of 11 sections. In normal ears, tPA stains positive were in 8 of 22 sections and strong positive were 10 of 22 sections, meanwhile, fibrin stains were negative in 8 of 12 sections and faint positive were in 3 of 12 sections. Quantitative analysis showed that the amount of tPA was 16.70 +/- 5.11 and 39.84 +/- 6.26 in ears with AOM and normal ones respectively (P < 0.05).

CONCLUSION

In adhesive ears the amount of tPA was less than that in the normal ears, whereas, the amount of Fibrin was greater in ears with AOM than that in normal ears. It indicates that fibrinolysis involved in the process of adhesion formation of AOM, which may acts as a key factor.

Impact of the putative differentiating agent sodium phenylbutyrate on myelodysplastic syndromes and acute myeloid leukemia

Sodium phenylbutyrate (PB) is an aromatic fatty acid with cytostatic and differentiating activity against malignant myeloid cells (ID(50), 1-2 mM). Higher doses induce apoptosis. Patients with myelodysplasia (n = 11) and acute myeloid leukemia (n = 16) were treated with PB as a 7-day continuous infusion repeated every 28 days in a Phase I dose escalation study. The maximum tolerated dose was 375 mg/kg/day; higher doses led to dose-limiting reversible neurocortical toxicity. At the maximum tolerated dose, PB was extremely well tolerated, with no significant toxicities; median steady-state plasma concentration at this dose was 0.29 +/- 0.16 mM. Although no patients achieved complete or partial remission, four patients achieved hematological improvement (neutrophils in three, platelet transfusion-independence in one). Other patients developed transient increases in neutrophils or platelets and decrements in circulating blasts. Monitoring of the percentage of clonal cells using centromere fluorescence in situ hybridization over the course of PB administration showed that hematopoiesis remained clonal. Hematological response was often associated with increases in both colony-forming units-granulocyte-macrophage and leukemic colony-forming units. PB administration was also associated with increases in fetal erythrocytes. These data document the safety of continuous infusion PB and provide preliminary evidence of clinical activity in patients with myeloid malignancies.

Comparative study of the clinical efficacy of two dosing regimens of flutamide

PURPOSE

We performed a randomized trial to compare the efficacy and toxicity of a new dose of flutamide (500 mg QD) with the currently recommended dose (250 mg q8h) in the treatment of advanced prostate cancer. The primary endpoints were percent of patients having normalization of prostate specific antigen (PSA), time to normalization, and percent change from baseline. Secondary endpoints were quality of life and toxicity.

PATIENTS

Altogether, 440 men aged 46 to 94 years (mean 71 years) with confirmed stage M(1) disease, documented PSA rise >0.2 ng/mL, ECOG status 0 to 2, no second neoplasm, no liver function tests > or = 1.5-fold normal values, and no previous treatment for metastatic disease were entered in the trial.

RESULTS

The PSA normalized by week 12 in 71% of the patients receiving 500-mg dose and 75% of those receiving the standard dose. The percent change in PSA was 89% and 96%, respectively. The treatment groups were not significantly different with respect to the incidence of adverse events: 71% v 68% in the 500-mg and 250-mg arms, respectively (P = 0.337).

CONCLUSIONS

When combined with castration, 500 mg of flutamide appears to be equally effective in lowering serum PSA and is not significantly more toxic than conventional dosing. The use of 500 mg QD instead of the standard 250 mg q8h would result in a cost savings of 30%.

Concurrent paclitaxel and radiation in the treatment of locally advanced head and neck cancer

PURPOSE

To determine the feasibility of an organ preservation regimen consisting of infusional paclitaxel administered concurrently with radiotherapy to patients with locally advanced head and neck squamous cell carcinoma (HNSCC).

PATIENTS AND METHODS

Thirty-three previously untreated patients with stage III or IV tumors were enrolled onto the study. Paclitaxel was administered as a 120-hour continuous infusion every 3 weeks during the course of radiation therapy. Sixteen patients received a paclitaxel dose of 105 mg/m(2), and 17 patients received 120 mg/m(2). Radiation was delivered in a standard format at 1.8 Gy/d to a total dose of 70.2 to 72 Gy.

RESULTS

Three months after therapy, a 76% complete response (CR) at the primary site and a 70% overall CR was achieved. At 36 months, locoregional control was 55.7%, overall survival was 57.8%, and disease-free survival was 51.1%. The median survival duration for all 33 patients was greater than 50 months at the time of this report. Local toxicities including mucositis, dysphagia, and skin reactions were severe but tolerable. All patients retained functional speech, and all but four patients were swallowing food 3 months after treatment. Steady-state plasma concentrations for paclitaxel were not achieved during a 120-hour infusion, suggesting a nonlinear process. Tumor volume quantified by pretreatment computerized tomography imaging was associated with likelihood of response and survival.

CONCLUSION

Paclitaxel administered as a 120-hour continuous infusion in combination with radiotherapy is a feasible and promising treatment for patients with advanced HNSCC.

[Effect of tsaoko-anemarrhenae decoction on intracerebral c-fos, c-jun mRNA expression in interrupting pentylentetrazol kindled epileptic rat model]

OBJECTIVE

To investigate the molecular biological mechanism of anti-epileptic effect of Tsaoko-Anemarrhenae decoction (TAD) on epileptic model rats.

METHODS

The pentylenetetrazol (PTZ) induced epileptic Sprague-Dawley rats were selected as the animal model. The effects of TAD on the c-fos, c-jun gene expression in the rats' brain were observed by in situ hybridisation.

RESULTS

The c-fos, c-jun gene expression was obviously increased, TAD could effectively block the gene expression of c-fos, c-jun, showing better antiepileptic effect.

CONCLUSION

The mechanism of TAD anti-epileptic effect might be correlated to the decrease of c-fos, c-jun gene expression.

[The protective effects of ciliary neurotrophic factor on inner ear damage induced by intensive impulse noise]

OBJECTIVE

To evaluate the feasibility of using ciliary neurotrophic factor(CNTF) to treat intensive impulse noise-induced inner ear damage.

METHODS

The guinea pigs were given either CNTF (CNTF group) or 0.9% sodium chloride (NS group) for 3 weeks after impulse noise exposure. The animals receiving neither medicine nor noise served as a control group. ABR threshold shifts, the cochlear AchE staining as well as the hair cell and spiral ganglion cell counting were carried out in three groups of animals.

RESULTS

The numbers of damaged hair cells and spiral ganglion cells in the CNTF group was less than that in the NS group. AchE activity alteration was also less severe in the CNTF group. Similar to the morphological results, changes in the auditory function, represented by the ABR threshold shifts, was less in the CNTF group.

CONCLUSION

CNTF can protect cochlear hair cells and spiral ganglion cells against intensive impulse noise exposure by decreasing degeneration and necrosis of the hair cells in some extent and expedite hearing recovery.

Inhibition of human liver cytochrome P-450 1A2 by the class IB antiarrhythmics mexiletine, lidocaine, and tocainide

Mexiletine, lidocaine, and tocainide are class IB antiarrhythmic drugs that are used for the treatment of ventricular arrhythmias and are known to inhibit drug metabolism. The objectives of this study were to characterize the inhibitory effects of mexiletine, lidocaine, and tocainide on cytochrome P-450 1A2 (CYP1A2) activity in human liver microsomes and to evaluate their relative inhibitory potencies by using a molecular model of this P-450 isozyme. The inhibitory effect of mexiletine, lidocaine, and tocainide on cytochrome CYP1A2 in human liver microsomes was examined with methoxyresorufin O-demethylase activity as an index of the catalytic activity of this P-450 isozyme. The kinetic inhibition types and Ki values were determined by Lineweaver-Burk plots and Dixon plots, respectively. Molecular modeling was used to assess the interaction of these agents with the CYP1A2 active site. Methoxyresorufin O-demethylase activity was inhibited 67 +/- 8%, 20 +/- 5%, and 7 +/- 4% by 2 mM mexiletine, lidocaine, and tocainide, respectively. Mexiletine and lidocaine exhibited competitive inhibition with Ki values of 0.28 +/- 0.12 mM and 1.54 +/- 0.74 mM, respectively, whereas the inhibition type of tocainide could not be determined because of its weak potency. A charge interaction between mexiletine and the Asp313 side chain in the CYP1A2 active site was found, and varying degrees of hydrogen bond formation between these three compounds and the CYP1A2 active site were observed. The in vitro inhibitory potencies in human liver microsomes (mexiletine > lidocaine > tocainide) are consistent with the structural interactions found in a molecular model of the active site of CYP1A2.

Effects of impulse noise on cortical response threshold and inner ear activity of succinic dehydrogenase and acetylcholinesterase in guinea pigs

The effects of impulse noise (firecrackers at 170 dB SPL, 1, 10, 20 rounds) on auditory cortical response threshold (CRT) and activity of succinic dehydrogenase (SDH) and acetylcholinesterase (AchE) in the inner ear were studied in 37 guinea pigs. The results showed that extent of damage in the cochlea was related to amount of exposure to the noise. Exposure to 10 rounds resulted in temporal threshold shift (TTS); to 20 rounds the result was permanent threshold shift (PTS). For the period when TTS existed, inverse correlation was noticed between enzyme activity change and CRT shift. The correlation could not be established when PTS was induced. The results suggest that the pathomechanism of PTS was more complex than that of TTS. The significance of the results is discussed.

Comparative inhibition of human cytochromes P450 1A1 and 1A2 by flavonoids

Flavonoids are a class of dietary phytochemicals that modulate various biological activities. The effects of flavone and five hydroxylated derivatives on the methoxyresorufin O-demethylase activity catalyzed by cDNA-expressed human cytochromes P450 (CYP)1A1 and 1A2 were examined. Flavone was a less potent inhibitor of CYP1A1 (IC50 = 0.14 microM) than CYP1A2 (IC50 = 0.066 microM). Four hydroxylated flavone derivatives (3-hydroxy-, 5-hydroxy-, 7-hydroxy-, and 3,7-dihydroxyflavone) were also potent inhibitors of CYP1A1 (IC50 < 0.1 microM) and CYP1A2 (IC50 < 0.3 microM). For CYP1A1, 7-hydroxyflavone exhibited a competitive mode of inhibition, with a Ki value of 0.015 microM and 6-fold selectivity for CYP1A1 over CYP1A2. 3,5,7-Trihydroxyflavone (galangin) showed the highest potency toward CYP1A2. The inhibition by galangin of the methoxyresorufin O-demethylase activity of CYP1A2 was mixed-type, with a Ki value of 0.008 microM. Galangin showed 5-fold selectivity in its inhibition of CYP1A2 over CYP1A1. The results indicate that some flavonoids have high potencies and selectivities for inhibition of CYP1A isozymes. This may have important implications for cancer prevention, as well as other pharmacological and toxicological effects of these compounds.

Inhibition of human cytochrome P450 1A2 by flavones: a molecular modeling study

Cytochrome P450 1A2 metabolizes a number of important drugs, procarcinogens, and endogenous compounds. Several flavones, a class of phytochemicals consumed in the human diet, have been shown to differentially inhibit human P450 1A2-mediated methoxyresorufin demethylase. A molecular model of this P450 was constructed in order to elucidate the molecular basis of the P450-flavone interaction. Flavone and its 3,5,7-trihydroxy and 3,5,7-trimethoxy derivatives were docked into the active site to assess their mode of binding. The site is hydrophobic and includes several residues that hydrogen bond with substituents on the flavone nucleus. The binding interactions of these flavones in the modeled active side are consistent with their relative inhibitory potentials, namely 3,5,7-trihydroxylflavone > flavone > 3,5,7-trimethoxylflavone, toward P450 1A2-mediated methoxyresorufin demethylation.

Inhibition of methoxyresorufin demethylase activity by flavonoids in human liver microsomes

Flavonoids are a class of dietary phytochemicals with anticarcinogenic properties. A series of ten structurally related flavonoids were evaluated for their effect on methoxyresorufin O-demethylase (MROD) activity in human liver microsomes. All compounds inhibited this cytochrome P450 1A2 (CYP1A2) mediated activity. 3,5,7-Trihydoxyflavone (galangin) was the most potent inhibitor, followed by 3-hydroxyflavone and flavone. The relative inhibitory potency of flavonoids is related to their structures. The results suggest that flavonoids may modulate pharmacological and toxicological effects mediated by CYP1A2.

[Treatment effects of fibroblast growth factors on blast-induced hearing loss]

Nineteen guinea pigs were chosen to measure the compound action potential (CAP) using the silver-ball electrode before and after explosion and 48 h after perfusion of acidic fibroblast growth factor (aFGF) and basic fibroblast growth factor (bFGF). After explosion the average CAP thresholds in the group perfused with bFGF and aFGF were 88.7 dB and 93.2 dB SPL respectivery, the CAP threshold in the control group was 119.4 dB SPL. The difference was significant. The results of the hair cell count from the surface preparation of the cochlea showed that hair cell damage in the control group was more severe than that in the group perfused with aFGF and bFGF. It suggests that aFGF and bFGF perfused to the cochlea may facilitate recovery processes of hearing loss and help to repair the hair cell following acoustic trauma.

Binding of beta-amyloid to the p75 neurotrophin receptor induces apoptosis. A possible mechanism for Alzheimer's disease

Alzheimer's disease is a neurodegenerative disorder characterized by the extracellular deposition in the brain of aggregated beta-amyloid peptide, presumed to play a pathogenic role, and by preferential loss of neurons that express the 75-kD neurotrophin receptor (p75NTR). Using rat cortical neurons and NIH-3T3 cell line engineered to stably express p75NTR, we find that the beta-amyloid peptide specifically binds the p75NTR. Furthermore, 3T3 cells expressing p75NTR, but not wild-type control cells lacking the receptor, undergo apoptosis in the presence of aggregated beta-amyloid. Normal neural crest-derived melanocytes that express physiologic levels of p75NTR undergo apoptosis in the presence of aggregated beta-amyloid, but not in the presence of control peptide synthesized in reverse. These data imply that neuronal death in Alzheimer's disease is mediated, at least in part, by the interaction of beta-amyloid with p75NTR, and suggest new targets for therapeutic intervention.

Effect of hyperbaric oxygen treatment on permanent threshold shift in acoustic trauma among rats

Impulse noise from firearms is a common cause of acute acoustic trauma (AAT). Recently hyperbaric oxygen treatment has become available in many hospitals treating AAT. We exposed 39 Wistar rats to intense impulse noise of 60 shots from the assault rifle (162 dB SPL). After the exposure 15 animals were given hyperbaric oxygen treatment (HBO) by 10 treatment cycles of 90 minutes 100% oxygen in 0.25 MPa, one treatment cycle per day. Four weeks after the exposure the hearing thresholds were measured with auditory brainstem response audiometry at frequencies of 1.0, 2.0, 4.0, 6.0, 8.0 and 10.0 kHz. Characteristics for the resulting noise-induced hearing loss were large variations in its severity not only between animals, but also between the ears of a single animal. The largest permanent threshold shifts were found at 6.0, 8.0 and 10.0 kHz. Most of the HBO-treated animals showed less threshold shift than the non-treated animals. The difference between the HBO group and the control group was only slightly statistically significant (p = 0.067).

The "toughening" phenomenon in rat's auditory organ

In audiological "toughening" or "conditioning" phenomenon prior exposure to moderate noise reduces the extent of hearing deterioration caused by the subsequent exposure to traumatic test noise known to cause inner ear damage. "Toughening" has been demonstrated in many mammalian laboratory animals such as guinea pig and chinchilla but not in rat or mouse. Our aim was to study the occurrence of this phenomenon in the rat. Ninety-one white male Wistar rats were divided into four groups: unexposed control group (U, n = 10), "conditioning" only (C, n = 32), "conditioning" plus test noise (C + T, n = 36) and test noise only (T, n = 13). Groups C and C + T were "conditioned" for 10 hours with 4.0 kHz OBN between 55 and 95 dB sound pressure levels (SPLs). After 10 hours rest groups C + T and T were exposed to the same noise at 105 dB SPL for 13 hours. The hearing thresholds were determined by auditory brainstem response audiometry (ABR) either immediately after or 3 weeks after the exposures. After that the animals were sacrificed. The cochleas were removed and perilymphatically fixed and further processed for quantitative cytocochleograms. Both the temporary (TTS) and the permanent threshold shifts (PTS) were smaller in animals which had been "conditioned" prior exposure to traumatic noise. Yet only 95 dB SPL "conditioning" gave statistically significant difference (p < 0.05) in PTS. From our results we conclude that "conditioning" effect seems to be present also in the rat. However to confirm this, further experiments are needed. The mechanisms behind "conditioning" are still unknown and also to clarify them, further efforts are needed.

Relation between plasma and saliva concentrations of enoxacin, ciprofloxacin, and theophylline

To assess the reliability of predicting plasma concentrations of enoxacin, ciprofloxacin, and theophylline from drug concentrations in saliva, six healthy volunteers received single oral doses of enoxacin, ciprofloxacin, and theophylline administered in combination on each of four separate study days, with different, doses separated by at least 5 days. Drug concentrations were determined by a newly developed high-performance liquid chromatography (HPLC) assay, which could measure simultaneously all three drugs in plasma or saliva. Saliva data from the postabsorptive phase after drug administration were used to minimize the effects of variation in absorption. There were good correlations between saliva and plasma concentrations of enoxacin, ciprofloxacin, and theophylline (r = 0.91, 0.88, and 0.98, respectively). The mean (+/-SD) saliva-to-plasma (S/P) ratio for theophylline was 0.63 +/- 0.06 with a coefficient of variation (CV) of 7.9 +/- 2.7%. In contrast, the S/P ratios and CV values for enoxacin and ciprofloxacin were 0.72 +/- 0.21 and 28.9 +/- 11.1%, and 0.58 +/- 0.15 and 25.3 +/- 6.7%, respectively. Because of the large inter- and intraindividual variability, saliva concentrations of enoxacin and ciprofloxacin are not reliable for predicting plasma concentrations. However, saliva may be used reliably for predicting plasma concentrations of theophylline.

Nerve growth factor rescues pigment cells from ultraviolet-induced apoptosis by upregulating BCL-2 levels

Apoptosis plays an important role in eliminating dysfunctional damaged cells. For skin, the best characterized injurious environmental agent is ultraviolet (UV) irradiation. Most of the damaging UV irradiation is absorbed in the epidermis and leads to apoptosis of keratinocytes. However, epidermal melanocytes appear to be protected from UV-induced apoptosis. We now report that in pure cultures melanocytic cells undergo characteristic apoptosis after physiologic UV exposures. However, nerve growth factor (NGF) supplementation protects them from this programmed cell death. Furthermore, we show that NGF protects melanocytic cells from UV-induced apoptosis by upregulating BCL-2 protein in these cells and that prior downregulation of BCL-2 abrogates the NGF protective effect on melanocytes. Our data suggest that NGF, known to be constitutively produced by epidermal keratinocytes and induced in these cells after UV irradiation, may preserve the population of cutaneous melanocytes that would otherwise be depleted by casual sun exposure.

[Effect of radix Ginseng-faeces Trogopterori combination on pharmacodynamics and effective chemical composition of radix Ginseng]

The experiments have shown that there is incompatibility on anti-stress because the action of Radix Ginseng alone is stronger than that of Radix Ginseng and Faeces Trogopterori combined, but there is little incompatibility on non-specific immune function when both are used. The analysis of chemical composition of Radix Ginseng has indicated that the acquired rate of total saponin from the semifinished products and Rg1 of Radix Ginseng is markedly increased when the two drugs are decocted together. The results suggest that the traditional theory is limited in holding that Radix ginseng and Faeces Trogopterori are incompatible with each other.

Simultaneous determination of theophylline, enoxacin and ciprofloxacin in human plasma and saliva by high-performance liquid chromatography

A simple reversed-phase high-performance liquid chromatographic method has been developed for the simultaneous determination of theophylline, ciprofloxacin and enoxacin in plasma and saliva. The biological fluid samples were extracted with methylene chloride-isopropyl alcohol prior to isocratic chromatography on a Waters C18 mu Bondapak column. Ultraviolet detection was carried out at 268 nm. The assay is linear for ciprofloxacin and enoxacin (0.05-10 micrograms/ml), and theophylline (0.1-20 micrograms/ml). The assay can be used to investigate the interaction of these two fluoroquinolones with theophylline.

The trk family of receptors mediates nerve growth factor and neurotrophin-3 effects in melanocytes

We have recently shown that (a) human melanocytes express the p75 nerve growth factor (NGF) receptor in vitro; (b) that melanocyte dendricity and migration, among other behaviors, are regulated at least in part by NGF; and (c) that cultured human epidermal keratinocytes produce NGF. We now report that melanocyte stimulation with phorbol 12-tetra decanoate 13-acetate (TPA), previously reported to induce p75 NGF receptor, also induces trk in melanocytes, and TPA effect is further potentiated by the presence of keratinocytes in culture. Moreover, trk in melanocytes becomes phosphorylated within minutes after NGF stimulation. As well, cultures of dermal fibroblasts express neurotrophin-3 (NT-3) mRNA; NT-3 mRNA levels in cultured fibroblasts are modulated by mitogenic stimulation, UV irradiation, and exposure to melanocyte-conditioned medium. Moreover, melanocytes constitutively express low levels of trk-C, and its expression is downregulated after TPA stimulation. NT-3 supplementation to cultured melanocytes maintained in Medium 199 alone prevents cell death. These combined data suggest that melanocyte behavior in human skin may be influenced by neurotrophic factors, possibly of keratinocyte and fibroblast origin, which act through high affinity receptors.

Brain mitochondrial citrate synthase and glutamate dehydrogenase: differential inhibition by fatty acyl coenzyme A derivatives

Organic acidemia is found in several metabolic encephalopathies (e.g., hepatic and valproate encephalopathies, Reye's syndrome, and hereditary organic acidemias). Although fatty acids are known to be neurotoxic, the underlying mechanisms have not been fully elucidated. It has been hypothesized that one mechanism underlying fatty acid neurotoxicity is the selective inhibition of rate-limiting and/or regulated tricarboxylic acid (TCA) cycle and related enzymes by fatty acyl-coenzyme A (CoA) derivatives. To test the hypothesis, this study has examined the effects of several fatty acyl-CoAs on citrate synthase (CS) and glutamate dehydrogenase (GDH) in brain mitochondria. At levels higher than 100 microM, butyryl-CoA (BCoA; a short-chain acyl-CoA; IC50 approximately 640 microM), octanoyl-CoA (OCoA; a medium-chain acyl-CoA; IC50 approximately 380 microM), n-decanoyl-CoA (DCoA; a medium-chain acyl-CoA; IC50 approximately 436 microM), and palmitoyl-CoA (PCoA; a long-chain acyl-CoA; IC50 approximately 340 microM) inhibited brain mitochondrial CS activity in a concentration-related manner. However, these fatty acyl-CoAs were less effective inhibitors (IC50 values for OCoA, DCoA, and PCoA being approximately 1260, 420, and 720 microM, respectively) of brain mitochondrial GDH activity. Compared to the other three acyl-CoAs investigated, BCoA was a very poor inhibitor of GDH. These results demonstrate that fatty acyl-CoAs are inhibitors of brain mitochondrial CS and GDH activities only at pathological/toxicological levels. Thus, the fatty acyl-CoA inhibition of brain mitochondrial CS and GDH is unlikely to assume major pathophysiological and/or pathogenetic importance.(ABSTRACT TRUNCATED AT 250 WORDS)