Pharmacokinetics of metronidazole, tetracycline and bismuth in healthy volunteers after oral administration of compound tablets containing a combination of metronidazole, tetracycline hydrochloride and bismuth oxide

BACKGROUND

To eradicate Helicobacter pylori in human pylorus and to heal duodenal ulcers, recently, a new formulation of combination tablets containing metronidazole 125 mg, tetracycline hydrochloride 125 mg and bismuth oxide 40 mg has been developed.

OBJECTIVE

To investigate the pharmacokinetics of metronidazole, tetracycline and bismuth in healthy Chinese volunteers after oral administration of the test formulation.

METHODS

A one-sequence, 3-period study was conducted in 12 Chinese healthy volunteers (6 male, 6 female). Volunteers each received single low dose (1 tablet) under fed condition in period 1, single high dose (3 tablets) under fasted condition in period 2, and single high dose (3 tablets) and multiple doses (3 tablets at once, 4 times daily for 7 consecutive days) under fed condition in period 3. Blood samples were collected and determined over 48 h in every period.

RESULTS AND CONCLUSION

After single high dose administration under fed condition, the C max of metronidazole, tetracycline and bismuth were 6.833 ± 0.742 μg/mL, 0.8513 ± 0.1253 μg/mL and 3.32 ± 1.89 ng/mL, respectively. The C max and AUC 0-48 of metronidazole increased in proportion to the doses within the tested dose range, but tetracycline and bismuth did not. Food caused 10% and 80% decrease of the C max for metronidazole and bismuth, respectively, but did not affect tetracycline. No gender effect was found on the pharmacokinetics of the 3 ingredients. In the steady state, the C av of metronidazole, tetracycline and bismuth were 20.75 ± 3.52 μg/mL, 1.900 ± 0.243 μg/mL and 5.61 ± 1.34 ng/mL, respectively.

Association of renal function with cardiac reverse remodeling and long-term outcome in heart failure patients following cardiac resynchronization therapy

BACKGROUND

Renal insufficiency (RI) is significantly associated with clinical prognosis in patients with heart failure (HF), but direct evidences on the relation between renal function and clinical outcome in patients receiving cardiac resynchronization therapy (CRT) are limited. The aim of the current study was to systematically evaluate the association of baseline and 6-month renal function with cardiac reverse remodeling and long-term outcome after CRT.

METHODS

We retrospectively evaluated 190 consecutive patients who underwent CRT at Fuwai Hospital from January 2008 to April 2013. Renal function tests, echocardiographic measurement, and clinical parameters at baseline and after 6 months of CRT were performed. Primary endpoint events included all-cause mortality, cardiac transplantation, and unplanned hospitalizations for HF.

RESULTS

At baseline, compared with normal renal function or mild RI (estimated glomerular filtration rate (eGFR) ≥60 ml×min(-1)×1.73 m(-2)), moderate-to-severe RI (eGFR <60 ml×min(-1)×1.73 m(-2)) exerted a negative influence on cardiac reverse remodeling parameters. At 6-month follow-up, 114 (60.0%) patients were classified as responders and showed significant renal function improvement, whereas renal function deteriorated in non-responders and subsequently 41 (25.6%) patients developed worsening renal function (WRF). During the mean follow-up of (24.3±17.1) months, both patients with baseline eGFR <60 ml×min(-1)×1.73 m(-2) and those with WRF experienced worse event-free survival (P < 0.01, respectively).

CONCLUSIONS

This analysis identified that baseline eGFR as well as WRF after CRT were found to be independent determinants of the combined endpoints of all-cause mortality and HF-related hospitalizations in CRT recipients.

Clinical outcomes of remission induction therapy for severe antineutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

To evaluate the reasons that complete remission is not achieved or maintained with original treatment in some patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) treated with rituximab (RTX) or with cyclophosphamide/azathioprine (CYC/AZA).

METHODS

The Rituximab in AAV trial was a randomized, double-blind, placebo-controlled trial comparing the rate of remission induction among patients treated with RTX (n = 99) and patients treated with CYC followed by AZA (n = 98). Glucocorticoids were tapered over a period of 5 months. The primary outcome measure was lack of disease activity without glucocorticoid treatment at 6 months. To determine the most important reason for failure to achieve the primary outcome, 7 hierarchical categories of reasons were defined retrospectively (uncontrolled disease, adverse event leading to therapy discontinuation, severe flare, limited flare, Birmingham Vasculitis Activity Score for Wegener's Granulomatosis >0, prednisone treatment at any dosage, and other).

RESULTS

Although remission (lack of disease activity) was achieved in 170 of the 197 patients (86%) in the first 6 months, the primary outcome measure was not achieved in 42%. There were 3 deaths. Twenty-four percent of the patients failed to achieve the primary end point due to active disease: 10 (5%) experienced uncontrolled disease in the first month and 37 (19%) experienced flares after initial improvement. In the majority of such patients, treatment with blinded crossover or according to best medical judgment led to disease control. Ninety-one percent of patients who had uncontrolled disease or experienced a severe flare had proteinase 3 (PR3)-ANCA. When patients with uncontrolled disease were excluded from analysis, those who were PR3-ANCA positive were found to experience fewer flares when treated with RTX compared to CYC/AZA (8 of 59 [14%] versus 20 of 62 [32%]; P = 0.02). Neither ANCA titers nor B cell counts predicted disease flare.

CONCLUSION

Current treatment regimens are largely successful in controlling AAV, but in approximately one-fourth of patients, active disease persists or recurs in the first 6 months despite treatment. PR3-ANCA positivity is a risk factor for recurrence or persistence of severe disease. ANCA titers and B cell detectability are poor predictors of both disease relapse and disease quiescence in the first 6 months.

Association of NPP1 polymorphism with postoperative progression of ossification of the posterior longitudinal ligament in Chinese patients

Ossification of the posterior longitudinal ligament (OPLL) is a condition of the spine that can cause paralysis by compressing the spinal cord. The aim of this study was to evaluate the possible role of nucleotide pyrophosphatase phosphodiesterase 1 gene (NPP1) polymorphism in the etiology and pathology of the OPLL in Chinese patients. DNA from patients with OPLL (N = 95) and without OPLL (N = 90) were genotyped for 4 NPP1 single-nucleotide polymorphisms (SNPs): A533C, C973T, IVS15-14T→C, and IVS20-11delT. An association study evaluated the relationship between specific SNP genotypes and susceptibility. We also evaluated whether genotypes of these SNPs were associated with disease severity and the probability of disease progression after surgery. The C973T and IVS15-14T SNPs were associated with the existence of the disease. The TT genotypes of C973T and IVS15→14T as well wild-type IVS20 (lack of deletion) were associated with more severe disease. Patients with the T deletion of IVS20 or the AA genotype of A533C had an approximately 3 times greater chance of not having than having disease progression after surgery. We concluded that the 4 SNPs analyzed appeared to have different effects on the etiology and pathology of OPLL. To our knowledge, this study is the first to investigate the relationship between these SNPs and disease progression after surgery. Our findings suggest that the presence of specific genotypes of the IVS20-11delT and A533C SNPs may predict disease outcome after surgical intervention.

Ionotropic glutamate receptors in paraventricular nucleus mediate adipose afferent reflex and regulate sympathetic outflow in rats

AIM

Chemical stimulation of white adipose tissue (WAT) induces adipose afferent reflex (AAR) and results in increases in renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP). The enhanced AAR contributes to sympathetic activation and hypertension in obesity rats. This study was designed to investigate whether N-methyl-D-aspartate receptors (NMDAR) and non-NMDAR in paraventricular nucleus (PVN) modulate AAR and sympathetic outflow.

METHODS

Renal sympathetic nerve activity and MAP were recorded in anesthetized rats. AAR was evaluated by the RSNA and MAP responses to the injection of capsaicin into the four sites of right inguinal WAT (8.0 nmol for each site).

RESULTS

Bilateral PVN microinjection of NMDAR antagonist AP5 or MK-801, or non-NMDAR antagonist CNQX attenuated AAR, RSNA and MAP. AP5 + CNQX caused greater effects than AP5 or CNQX alone and almost abolished AAR. NMDAR agonist NMDA or non-NMDAR agonist AMPA enhanced the AAR, and increased RSNA and MAP, which were prevented by AP5 or CNQX pre-treatment respectively. Casein kinase 2 inhibitor DRB, NR2A antagonist NVP-AAM077 or NR2B antagonist CP-101,606 attenuated AAR, RSNA and MAP. NVP-AAM077 + CP-101,606 caused greater effects than NVP-AAM077 or CP-101,606 alone. Bilateral baroreceptor denervation and vagotomy enhanced AAR, which was abolished by PVN pre-treatment with AP5 + CNQX. Furthermore, AP5 + CNQX abolished the AAR induced by leptin in iWAT.

CONCLUSION

Both NMDAR and non-NMDAR in the PVN mediate AAR and contribute to the tonic control of sympathetic outflow and blood pressure. CK2, NR2A and NR2B subunits of NMDAR in the PVN are involved in the NMDAR-mediated tonic control of AAR, RSNA and MAP.

β-Cell differentiation and regeneration in type 1 diabetes

Pancreatic insulin-producing β-cells have traditionally been viewed as a quiescent cell population. However, several recent lines of evidence indicated that like most tissues the β-cell mass is dynamically regulated with ongoing β-cell regeneration throughout life to replenish lost or damaged β-cells. In type 1 diabetes (T1D), this fine-tuned balance between β-cell death and β-cell renewal in the endocrine pancreas is lost and the deficit in β-cell mass is largely caused by autoimmune-mediated apoptosis. Currently, the concept that a cure for T1D will require both re-establishment of immunological tolerance along with replacement or regeneration of a functional β-cell mass in T1D patients is generally accepted. In this study our current understanding of the events directing β-cell replication, β-cell reprogramming from different cell types and β-cell regeneration is reviewed, in view of the results of various immunomodulatory strategies aiming at blocking autoimmune responses against pancreatic β-cells and at improving β-cell mass and function in subjects with T1D.

An efficient lattice Boltzmann model for indoor airflow and particle transport

The three-dimensional multiple-relaxation-time LB (MRT-LB) and Lagrangian particle tracking methods were applied to simulate turbulent airflow and particle dispersion in a ventilated room with a partition. The turbulent airflow was simulated by large eddy simulation (LES) using the MRT-LB method with the Smagorinsky model. This method was verified by comparing it with experimental and other numerical results. Good agreement was observed between airflow simulation and experimental data. It is also demonstrated that the LES carried out by the MRT-LB method can produce airflow results very similar to the RNG LES and provide better prediction than the standard and RNG k-ε models. In order to further improve the efficiency of the MRT-LB method, the multi-block grid refinement (MBGR) technique was used. The accuracy and efficiency of the MBGR and the consistency of physical quantities across the interface were investigated. In simulation of particle dispersion in the model room, particles with diameters of 1 and 10 µm were considered. It is shown that this model can successfully capture dispersion characteristics of particles.

Blood pressure reducing effects of piromelatine and melatonin in spontaneously hypertensive rats

BACKGROUND

Recently, widespread interest has grown regarding melatonin treatment of hypertension including its cardioprotective effects. Studies in rodents indicate that melatonin plays a role in the pathogenesis of hypertension in rats with metabolic syndrome. Piromelatine, a melatonin agonist, serotonin 5-HT-1A and 5-HT-1D agonist and serotonin 5-HT2B antagonist is a multimodal agent with sleep promoting, anti-diabetic, analgesic, anti-neurodegenerative, anxiolytic and antidepressant potential, currently in development for the treatment of insomnia.

AIM

In this report we assessed the effects of piromelatine and melatonin treatment on blood pressure in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats.

MATERIALS AND METHODS

Five groups of 12-wk-old rats (10/group) were treated for 5 weeks with a vehicle, piromelatine (5, 15 and 50 mg/kg BW) and melatonin (10 mg/kg BW) and an age-matched WKY control group. Systolic blood pressure (tail-cuff method) was measured weekly at 9:00 a.m. and at 9:00 p.m. The rats body weight, plasma glucose, insulin, triglyceride, adiponectin, total cholesterol, HDL and LDL/VLDL cholesterol were also measured.

RESULTS

Our results showed that both piromelatine and melatonin reduced SHR blood pressure significantly both during the morning and the evening. Piromelatine, but not melatonin, also reduced SHR body weight gain and both significantly decreased plasma glucose and insulin levels and increased adiponectin levels.

CONCLUSIONS

Piromelatine, similar to melatonin, has an antihypertensive effect and also attenuates body weight, improves metabolic profiles and might be useful in the treatment of hypertension and the metabolic syndrome.

Medium modification of jet fragmentation in Au+Au collisions at √[s(NN)]=200 GeV measured in direct photon-hadron correlations

The jet fragmentation function is measured with direct photon-hadron correlations in p+p and Au+Au collisions at √[s(NN)]=200 GeV. The p(T) of the photon is an excellent approximation to the initial p(T) of the jet and the ratio z(T)=p(T)(h)/p(T)(γ) is used as a proxy for the jet fragmentation function. A statistical subtraction is used to extract the direct photon-hadron yields in Au+Au collisions while a photon isolation cut is applied in p+p. I(AA), the ratio of hadron yield opposite the photon in Au+Au to that in p+p, indicates modification of the jet fragmentation function. Suppression, most likely due to energy loss in the medium, is seen at high z(T). The associated hadron yield at low z(T) is enhanced at large angles. Such a trend is expected from redistribution of the lost energy into increased production of low-momentum particles.

Interferon alpha treatment of patients with impaired interferon gamma signaling

Patients with deficiency in the interferon gamma receptor (IFN-γR) are unable to respond properly to IFN-γ and develop severe infections with nontuberculous mycobacteria (NTM). IFN-γ and IFN-α are known to signal through STAT1 and activate many downstream effector genes in common. Therefore, we added IFN-α for treatment of patients with disseminated mycobacterial disease in an effort to complement their IFN-γ signaling defect. We treated four patients with IFN-γR deficiency with adjunctive IFN-α therapy in addition to best available antimicrobial therapy, with or without IFN-γ, depending on the defect. During IFN-α treatment, ex vivo induction of IFN target genes was detected. In addition, IFN-α driven gene expression in patients' cells and mycobacteria induced cytokine response were observed in vitro. Clinical responses varied in these patients. IFN-α therapy was associated with either improvement or stabilization of disease. In no case was disease exacerbated. In patients with profoundly impaired IFN-γ signaling who have refractory infections, IFN-α may have adjunctive anti-mycobacterial effects.

A nanomaterial-based breath test for distinguishing gastric cancer from benign gastric conditions

Background:

Upper digestive endoscopy with biopsy and histopathological evaluation of the biopsy material is the standard method for diagnosing gastric cancer (GC). However, this procedure may not be widely available for screening in the developing world, whereas in developed countries endoscopy is frequently used without major clinical gain. There is a high demand for a simple and non-invasive test for selecting the individuals at increased risk that should undergo the endoscopic examination. Here, we studied the feasibility of a nanomaterial-based breath test for identifying GC among patients with gastric complaints.

Methods:

Alveolar exhaled breath samples from 130 patients with gastric complaints (37 GC/32 ulcers / 61 less severe conditions) that underwent endoscopy/biopsy were analyzed using nanomaterial-based sensors. Predictive models were built employing discriminant factor analysis (DFA) pattern recognition, and their stability against possible confounding factors (alcohol/tobacco consumption; Helicobacter pylori) was tested. Classification success was determined (i) using leave-one-out cross-validation and (ii) by randomly blinding 25% of the samples as a validation set. Complementary chemical analysis of the breath samples was performed using gas chromatography coupled with mass spectrometry.

Results:

Three DFA models were developed that achieved excellent discrimination between the subpopulations: (i) GC vs benign gastric conditions, among all the patients (89% sensitivity; 90% specificity); (ii) early stage GC (I and II) vs late stage (III and IV), among GC patients (89% sensitivity; 94% specificity); and (iii) ulcer vs less severe, among benign conditions (84% sensitivity; 87% specificity). The models were insensitive against the tested confounding factors. Chemical analysis found that five volatile organic compounds (2-propenenitrile, 2-butoxy-ethanol, furfural, 6-methyl-5-hepten-2-one and isoprene) were significantly elevated in patients with GC and/or peptic ulcer, as compared with less severe gastric conditions. The concentrations both in the room air and in the breath samples were in the single p.p.b._v range, except in the case of isoprene.

Conclusion:

The preliminary results of this pilot study could open a new and promising avenue to diagnose GC and distinguish it from other gastric diseases. It should be noted that the applied methods are complementary and the potential marker compounds identified by gas-chromatography/mass spectrometry are not necessarily responsible for the differences in the sensor responses. Although this pilot study does not allow drawing far-reaching conclusions, the encouraging preliminary results presented here have initiated a large multicentre clinical trial to confirm the observed patterns for GC and benign gastric conditions.

Pharmacokinetics, safety and tolerability of pirfenidone and its major metabolite after single and multiple oral doses in healthy Chinese subjects under fed conditions

BACKGROUND AND OBJECTIVE

Pirfenidone is a promising antifibrotic agent with therapeutic potential for idiopathic pulmonary fibrosis. This study aimed to evaluate the pharmacokinetics and urinary excretion of pirfenidone and its major metabolite 5-carboxy-pirfenidone in healthy Chinese subjects under fed conditions.

METHODS

20 healthy subjects of either sex were recruited in this randomized, single-center, and open-label, single ascending doses (200, 400, and 600 mg) and multiple doses (400 mg, 3 times daily) study. Safety was assessed by adverse events, ECGs, vital signs, and clinical laboratory parameters. Blood and urine samples were analyzed with a validated LC/MS method.

RESULTS AND CONCLUSIONS

Pirfenidone was safe and well tolerated. After single-dose administration, pirfenidone was rapidly absorbed with a mean Tmax of 1.8-2.2 h and a mean t1/2 of 2.1-2.4 h. 5-carboxy-pirfenidone was rapidly formed with a mean Tmax of 1.5-2.2 h and a mean t1/2 of 2.1-2.6 h. Cmax and AUC for both parent and metabolite were dose proportional over the 200-600 mg dose range. No gender effect was found. In the steady state, the accumulation index (R) estimated for the 3 dosing intervals ranged from 1.1 to 1.5 for both pirfenidone and 5-carboxy-pirfenidone, indicating that the exposure of pirfenidone and 5-carboxy-pirfenidone increased slightly with repeated dosing, but t1/2 and CL/F remained unchanged. Metabolism is the primary mechanism of drug clearance of pirfenidone. About 87.76% of the administered pirfenidone was excreted in urine in the form of 5-carboxy-pirfenidone, while only 0.6159% of the administered pirfenidone was detected as the unchanged form in urine.

Pharmacokinetics of a new immediate-release compound omeprazole capsule and its comparison with the enteric-coated formulation under fasting and fed conditions

The present study was conducted to describe the pharmacokinetic profile of immediate-release compound omeprazole capsule and compare it with the enteric-coated formulation under fasting and fed condition.This study was designed to phase I, open-label, randomized, 3-part clinical trial. 12 subjects in part one received single doses (20 mg and 40 mg) and repeated doses (20 mg). Different 30 subjects in part 2 (fasting condition) and part 3 (fed condition) received either compound omeprazole capsule (40 mg) or delayed-release omeprazole (40 mg) separated by 7 days.Compound omeprazole capsule showed dose non-proportionality in the range from 20 mg to 40 mg. The AUC0-t of 20 mg omeprazole is 78% higher after repeated doses. The C max was higher and T max was lower for compound omeprazole capsule than delayed-release omeprazole. 90% CIs for AUC0-t of the 2 periods (test/reference) under fasting and fed conditions were 106.3% (102.2%~109.2%) and 104.1% (93.4%~109.6%), respectively. Presence of food reduced the rate (C max) and extent (AUC0-t) of systemic exposure of the test and reference formulations from 1 462 to 777 ng · mL-1, 1 055 to 602 ng · mL-1, 2 597 to 1 852 ng · h · mL-1 and 2 454 to 1 873 ng · h · mL-1, respectively.Exposed dose of omeprazole in subjects with compound omeprazole capsule was time- and dose-dependent. Compared with delayed-release omeprazole, compound omeprazole capsule had rapid but similar degree of absorption of omeprazole.

A genome-wide RNAi screen identifies proteins modulating aberrant FLT3-ITD signaling

Fms-like tyrosine kinase-3 is a commonly mutated gene in acute myeloid leukemia, with about one-third of patients carrying an internal-tandem duplication of the juxtamembrane domain in the receptor (FLT3-ITD). FLT3-ITD exhibits altered signaling quality, including aberrant activation of STAT5. To identify genes affecting FLT3-ITD-mediated STAT5 signaling, we performed an esiRNA-based RNAi screen utilizing a STAT5-driven reporter assay. Knockdowns that caused reduced FLT3-ITD-mediated STAT5 signaling were enriched for genes encoding proteins involved in protein secretion and intracellular protein transport, indicating that modulation of protein transport processes could potentially be used to reduce constitutive STAT5 signaling in FLT3-ITD-positive cells. The relevance of KDELR1, a component involved in the Golgi-ER retrograde transport, was further analyzed. In FLT3-ITD-expressing leukemic MV4-11 cells, downregulation of KDELR1 resulted in reduced STAT5 activation, proliferation and colony-forming capacity. Stable shRNA-mediated depletion of KDELR1 in FLT3-ITD-expressing 32D cells likewise resulted in reduced STAT5 signaling and cell proliferation. Importantly, these cells also showed a reduced capacity to generate a leukemia-like disease in syngeneic C3H/HeJ mice. Together our data suggest intracellular protein transport as a potential target for FLT3-ITD driven leukemias, with KDELR1 emerging as a positive modulator of oncogenic FLT3-ITD activity.

Clonal diversity of recurrently mutated genes in myelodysplastic syndromes

Recent studies suggest that most cases of myelodysplastic syndrome (MDS) are clonally heterogeneous, with a founding clone and multiple subclones. It is not known whether specific gene mutations typically occur in founding clones or subclones. We screened a panel of 94 candidate genes in a cohort of 157 patients with MDS or secondary acute myeloid leukemia (sAML). This included 150 cases with samples obtained at MDS diagnosis and 15 cases with samples obtained at sAML transformation (8 were also analyzed at the MDS stage). We performed whole-genome sequencing (WGS) to define the clonal architecture in eight sAML genomes and identified the range of variant allele frequencies (VAFs) for founding clone mutations. At least one mutation or cytogenetic abnormality was detected in 83% of the 150 MDS patients and 17 genes were significantly mutated (false discovery rate ≤0.05). Individual genes and patient samples displayed a wide range of VAFs for recurrently mutated genes, indicating that no single gene is exclusively mutated in the founding clone. The VAFs of recurrently mutated genes did not fully recapitulate the clonal architecture defined by WGS, suggesting that comprehensive sequencing may be required to accurately assess the clonal status of recurrently mutated genes in MDS.