7α,8α-Epoxynagilactones and their glucosides from the twigs of Podocarpus nagi: Isolation, structures, and cytotoxic activities

A phytochemical investigation of twigs of Podocarpus nagi resulted in the identification of eight new type B nagilactones (1-8), all bearing a 7α,8α-epoxy-9(11)-enolide substructure, along with two known analogs (9-10). Their structures were determined on the basis of spectroscopic analysis, including HRESIMS, IR and NMR experiments, and X-ray crystallographic analysis. In vitro cytotoxic assay exhibited that compounds 1, 2, 9 and 10 could induce antiproliferation against three different types of human cancer cells while compounds 3 and 5 were inactive. Notably, the IC₅₀ value of compound 1 is 0.208μM for A431 human epidermoid carcinoma cells, reaching the same level as the positive control combretastatin A-4 (0.104μM). Furthermore, compound 1 performed a strong inhibition of cancer cells by triggering apoptosis and arresting the cell cycle at G₁ phase. These results unfold potential anticancer therapeutic applications of type B nagilactones.

Non-targeted metabolite profiling and specific targeted discrimination strategy for quality evaluation of Cortex Phellodendri from different varieties

Cortex Phellodendri is derived from two species of Phellodendron amurense Rupr. and Phellodendron chinense Schneid. Traditionally, the two species are utilized interchangeably under the name of “huangbo” in the clinic because they are believed to share the same clinical efficacy. However, the chemical analysis in vitro couldn't directly reflect the pharmacological effects. Therefore, whether the constituents could be absorbed into the blood becomes the uppermost problem to account for the clinical efficacy differences of the two species. Therefore, a rapid and sensitive approach to differentiate the two species of Cortex Phellodendri based on non-targeted metabolite profiling and the specific targeted discrimination strategy was first established. Samples from different cultivars were clearly discriminated by principal component analysis and orthogonal partial least squares discriminant analysis. 17 prototype compounds and 22 metabolites contributing to the group separation were identified and tentatively characterized, three of which were found for the first time. Moreover, six of them were screened out as the chemical markers which contribute most to the differences between the two species. Taken together, the application of the non-targeted metabolite profiling and specific targeted discrimination strategy is suitable for the assessment of Cortex Phellodendri.

Non-targeted metabolite profiling and specific targeted discrimination strategy coupled with pattern recognition to differentiate the two varieties in rats.

Metabolic profile elucidation of Zhi-Zi-Da-Huang decoction in rat intestinal bacteria using high-resolution mass spectrometry combined with multiple analytical perspectives

1. Zhi-Zi-Da-Huang decoction (ZZDHD) has been widely used for the treatment of alcoholic jaundice, alcoholic liver disease, and acute hepatitis in China for thousands of years. Conventionally decoctions are administered orally, after which the metabolism caused by the enzymes in intestinal bacteria may influence significantly on the curative effects or toxicity. 2. In this work, the comprehensive metabolic process of ZZDHD in intestinal bacteria was investigated reliably using high-resolution HPLC-DAD-ESI-TOF/MS. Besides, a novel strategy for major-to-trace metabolites identification which integrated information derived from diagnostic fragment ions, mass spectral similarity filter strategy, dynamic metabolic change of target compounds and relevant behavior in LC-MS was adopted. 3. As a result, 45 compounds, including 26 bio-converted prototypes and 19 newly generated metabolites were detected and tentatively identified. The metabolic profile of ZZDHD in gastro-intestinal was subsequently elucidated. Deglycosylation, oxidation, reduction, acetylation, and ring cleavage were all observed in the biotransformation of the decoction. Among the rest, deglycosylation was found to be the predominant metabolic pathway. 4. The results obtained herein provided a practical strategy for metabolic profile elucidation of traditional herbal medicines. Moreover, it would be helpful to unravel how the oral decoctions play the therapeutic role in vivo.

Risk of low-energy fracture in type 2 diabetes patients: a meta-analysis of observational studies

In this meta-analysis, evidence of an association between type 2 diabetes mellitus (T2DM) and low-energy fractures has been evaluated including 12 observational studies. The results suggested that T2DM patients had an enhanced risk of low-energy fractures.

INTRODUCTION

Type 1 diabetes mellitus (T1DM) patients have been shown to be at enhanced risk of fracture injury, but less is known about low-energy fractures among patients with T2DM.

METHODS

We performed a meta-analysis of 12 observational studies identified in Medline and EMBASE that included 938,742 participants, including 30,827 low-energy fracture cases. The incidence rate ratios (IRRs) of low-energy fractures were determined using a random-effects model.

RESULTS

The IRRs of low-energy fracture for men and women were 1.37 (95% confidence interval [CI], 0.94-2.00; p = 0.096) and 1.22 (95% CI, 1.09-1.35; p = 0.000), respectively, and the overall IRR was 1.23 (95% CI, 1.12-1.35; p = 0.000). The IRRs for hip and vertebral fractures were 1.08 (95% CI, 1.02-1.15; p = 0.007) and 1.21 (95% CI, 0.98-1.48; p = 0.073), respectively. The IRRs of low-energy fracture in case-control, prospective, retrospective, and cross-sectional studies were 1.18 (95% CI, 0.81-1.72; p = 0.380), 1.17 (95% CI, 1.05-1.32, p = 0.006), 1.15 (95% CI, 1.02-1.29; p = 0.020), and 1.60 (95% CI, 1.21-2.12; p = 0.001), respectively. The IRRs of low-energy fracture for less than 5 years, 5 to 10 years, and more than 10 years were 1.30 (95%, CI 1.13-1.50; p = 0.000), 1.05 (95% CI, 1.03-1.08; p = 0.000), and 1.19 (95% CI, 1.00-1.41; p = 0.049), respectively.

CONCLUSIONS

Patients with T2DM had a greater risk of low-energy fracture especially of the hip, compared with that in non-diabetic subjects. However, since according to our funnel plot a publication bias may be present and due to study heterogeneity as well as the limited number of publications, the finding needs to be interpreted with caution.

Modulation of periodontitis progression using pH-responsive nanosphere encapsulating metronidazole or N-phenacylthialzolium bromide

BACKGROUND AND OBJECTIVE

This study aimed to develop pH-responsive polylactide-glycolic acid co-polymer and chitosan (PLGA/chitosan) nanosphere as an inflammation-responsive vehicle and evaluate the potential of the nanosphere encapsulating metronidazole, an antibiotic, and N-phenacylthiazolium bromide (PTB), a host modulator, for treating periodontitis.

MATERIAL AND METHODS

PLGA/chitosan nanospheres were fabricated using oil-in-water emulsion method. Experimental periodontitis was induced on the rat maxillae, and the sites were randomly allocated to four treatment categories, including periodontitis alone (PR), periodontitis with nanospheres alone, nanospheres encapsulating metronidazole (MT) and nanospheres encapsulating PTB (PB). The ligature was retained until the animals were killed, and the treatment outcome was evaluated by the progression of periodontal bone loss (PPBL), inflammatory cell infiltration and collagen deposition.

RESULTS

The encapsulated drug was released rapidly from the nanospheres without significant initial burst release at pH 5.5. Compared with group PR, PPBL was significantly reduced in groups MT and PB on day 4 (P<.05). On day 21, PPBL was significantly lower in group PB (P<.05). In groups MT and PB, inflammation was significantly reduced in groups MT and PB relative to groups PR and periodontitis with nanospheres alone (P<.05), and collagen deposition was significantly greater relative to group PR (P<.05).

CONCLUSION

PLGA/chitosan nanospheres encapsulating metronidazole or PTB showed potential for modulating periodontitis progression.

Gq-activated fibroblasts induce cardiomyocyte action potential prolongation and automaticity in a three-dimensional microtissue environment

Cardiac fibroblasts (CFs) are known to regulate cardiomyocyte (CM) function in vivo and in two-dimensional in vitro cultures. This study examined the effect of CF activation on the regulation of CM electrical activity in a three-dimensional (3-D) microtissue environment. Using a scaffold-free 3-D platform with interspersed neonatal rat ventricular CMs and CFs, G_q-mediated signaling was selectively enhanced in CFs by Gα_q adenoviral infection before coseeding with CMs in nonadhesive hydrogels. After 3 days, the microtissues were analyzed by signaling assay, histological staining, quantitative PCR, Western blots, optical mapping with voltage- or Ca²⁺-sensitive dyes, and microelectrode recordings of CF resting membrane potential (RMP_CF). Enhanced G_q signaling in CFs increased microtissue size and profibrotic and prohypertrophic markers. Expression of constitutively active Gα_q in CFs prolonged CM action potential duration (by 33%) and rise time (by 31%), prolonged Ca²⁺ transient duration (by 98%) and rise time (by 65%), and caused abnormal electrical activity based on depolarization-induced automaticity. Constitutive G_q activation in CFs also depolarized RMP_CF from -33 to -20 mV and increased connexin 43 and connexin 45 expression. Computational modeling confers that elevated RMP_CF and increased cell-cell coupling between CMs and CFs in a 3-D environment could lead to automaticity. In conclusion, our data demonstrate that CF activation alone is capable of altering action potential and Ca²⁺ transient characteristics of CMs, leading to proarrhythmic electrical activity. Our results also emphasize the importance of a 3-D environment where cell-cell interactions are prevalent, underscoring that CF activation in 3-D tissue plays a significant role in modulating CM electrophysiology and arrhythmias.NEW & NOTEWORTHY In a three-dimensional microtissue model, which lowers baseline activation of cardiac fibroblasts but enables cell-cell, paracrine, and cell-extracellular matrix interactions, we demonstrate that selective cardiac fibroblast activation by enhanced G_q signaling, a pathophysiological trigger in the diseased heart, modulates cardiomyocyte electrical activity, leading to proarrhythmogenic automaticity.

Chinese Data of Efficacy of Low- and High-Dose Iodine-131 for the Ablation of Thyroid Remnant

BACKGROUND

Chinese data on the efficacy of low- and high-dose radioiodine for thyroid remnant are still absent. The aim of the study was to investigate whether a low dose of radioiodine is as effective as a high dose for remnant ablation in Chinese patients.

METHODS

Patients presenting for radioiodine ablation in the authors' department were included. Inclusion criteria were aged ≥16 years, total or near-total thyroidectomy, tumor-node-metastasis (TNM) stage of pT1-3, any N stage, and M0. All patients were randomly allocated to either the high-dose group of 3700 MBq or the low-dose group of 1850 MBq for remnant ablation. The response to treatment was defined as successful or unsuccessful after a six- to nine-month interval. Ablation was considered to be successful if patients fulfilled the following criteria: no tracer uptake in the thyroid bed on diagnosis whole-body scanning and a negative level of serum thyroglobulin.

RESULTS

There were 327 patients enrolled between January 2013 and December 2014. More than 95% had papillary thyroid cancer. Data could be analyzed for 278 cases (M_age = 44 years; 71.6% women), 155 in the low-dose group and 123 in the high-dose group. The rate of initial successful ablation was 84.2% in all patients, 82.6% in the low-dose group, and 86.2% in the high-dose group. There was no difference between the two groups (p = 0.509).

CONCLUSIONS

In Chinese patients with differentiated thyroid carcinoma, the low dose of 1850 MBq radioiodine activity is as effective as a high dose of 3700 MBq for thyroid remnant ablation.

[Study of prevention and control of delirium in ventilated patients by simulating blockage of circadian rhythm with sedative in intensive care unit]

OBJECTIVE

To explore the effect of giving sedatives according to the circadian rhythm in prevention of occurrence of delirium and the prognosis of patients undergoing mechanical ventilation in intensive care unit (ICU).

METHODS

A prospective double-blinded randomized controlled trial (RCT) was conducted. The patients admitted to Department of Critical Care Medicine of the Second Hospital of Lanzhou University from July 2014 to February 2015, undergoing invasive mechanical ventilation over 12 hours were enrolled. All the patients were given fentanyl for analgesia, and they were randomly divided into simulated circadian clock group (study group, n = 35) and non-simulated circadian clock group (control group, n = 35). The patients in each group were subdivided into three subgroups according to the kinds of sedative drugs, namely dexmedetomidine group (n = 8), propofol group (n = 14), and dexmedetomidine combined with propofol group (combination group, n = 13). Visual analogue scale (VAS) standard and Richmond agitation-sedation scale (RASS) were used to control the analgesic and to quantify the depth of sedation by titrating the dose of sedative drugs, the simulated circadian clock was set to control the RASS score at 0-1 during the day, and -1 to -2 at night in study group. The RASS score in the control group was set at -1 to -2 day and night. The urine 6-hydroxy acid melatonin (aMT6s) levels at different time points in the first diurnal rhythm (06:00, 12:00, 18:00, 24:00) were determined by enzyme linked immunosorbent assay (ELISA). The incidence of delirium, severe hypotension, severe bradycardia and other adverse reactions, duration of mechanical ventilation and the time of extubation, length of ICU stay, amount of sedative and analgesic drugs used were recorded. The correlation between delirium and other indexes was analyzed by using Spearman correlation analysis.

RESULTS

(1) There were no significant differences in gender, age, acute physiology and chronic health evaluation II (APACHEII) score among groups. (2) Urine aMT6s levels did not show circadian rhythm in both groups, aMT6s level at 06:00 in study group showed an increasing tendency as compared with the control group, but the difference was not statistically significant. (3) Compared with the control group, the incidence of delirium was significantly lowered in the study group (14.3% vs. 37.1%, P = 0.029), but no significant differences were found in the incidence of severe hypotension or severe bradycardia (20.0% vs. 25.7%, 11.4% vs. 20.0%, both P > 0.05). In simulated circadian clock group, the incidence of delirium in dexmedetomidine group was significantly lower than that of the propofol group (6.3% vs. 32.1%, P < 0.05). (4) Compared with control group with the same sedative, the duration of mechanical ventilation, extubation time, length of ICU stay were significantly shortened, and the dosage of sedative drugs used was reduced in study group (all P < 0.05). In simulated circadian clock group, the duration of mechanical ventilation in dexmedetomidine group was significantly shorter than that of propofol group and combination group (hours: 75.75±26.78 vs. 102.00±26.31 and 100.31±25.38, both P < 0.05), and the length of ICU stay was significantly shorter than that of propofol group (days: 5.75±1.04 vs. 7.00±1.52, P < 0.05). (5) The occurrence of delirium was positively correlated with duration of mechanical ventilation (r = 0.705), extubation time (r = 0.704), length of ICU stay (r = 0.666, all P = 0.000), and no correlation was found between the occurrence of delirium and aMT6s level at 06:00, 12:00, 18:00, and 24:00 (r = -0.135, r = 0.163, r = 0.269, r = -0.077, all P > 0.05).

CONCLUSIONS

Administration of sedatives according to simulating circadian time could decrease the duration of mechanical ventilation, extubation time, and the length of ICU stay, decrease the dosage of sedative drugs, and reduce the incidence of delirium. Dexmedetomidine could reduce the incidence of delirium, and improve the prognosis of patients.

Steroid therapy and the risk of osteonecrosis in SARS patients: a dose-response meta-analysis

This meta-analysis synthesized current evidence from 10 trials to evaluate the association between steroid therapy and osteonecrosis incidence in patients with severe acute respiratory syndrome (SARS). Our results suggest that higher cumulative doses and longer treatment durations of steroids are more likely to lead to the development of osteonecrosis in SARS patients.

INTRODUCTION

The link between steroid treatment and the risk of osteonecrosis in SARS patients remains unknown. The present meta-analysis aimed to examine the dose-response association between steroid therapy and osteonecrosis incidence in SARS patients. The sex differences in the development of steroid-induced osteonecrosis were also examined.

METHODS

We searched PubMed, Web of Science, CNKI, and WANFANG for studies that involved steroid therapy and reported osteonecrosis data in SARS patients. Two authors independently extracted the data from the individual studies, and the rate ratio (RR) of osteonecrosis was calculated using random-effect models.

RESULTS

Ten studies with 1137 recovered SARS patients met the inclusion criteria. Close relationships between osteonecrosis incidence and both the cumulative dose and treatment duration of steroids were observed. The summary RR of osteonecrosis was 1.57 (95% confidence interval (CI) 1.30-1.89, p < 0.001) per 5.0 g increase in the cumulative dose of steroids and was 1.29 (95% CI 1.09-1.53, p = 0.003) for each 10-day increment of increase in treatment duration. The relationship was non-linear (p _non-linear < 0.001 and p _non-linear = 0.022). There were no significant differences in the risk of developing osteonecrosis between the male and female patients (RR 0.01, 95% CI -0.03 to 0.06, p = 0.582).

CONCLUSIONS

SARS patients who received higher cumulative doses and longer treatment durations of steroids were more likely to develop osteonecrosis, and there were no sex differences in this dose-dependent side effect. Our findings suggest that it is important to reduce osteonecrosis risk by modifying the cumulative dose and the treatment duration of steroids in SARS patients.

China Patient-centered Evaluative Assessment of Cardiac Events Prospective Study of Acute Myocardial Infarction: Study Design

Background:

Despite the rapid growth in the incidence of acute myocardial infarction (AMI) in China, there is limited information about patients’ experiences after AMI hospitalization, especially on long-term adverse events and patient-reported outcomes (PROs).

Methods:

The China Patient-centered Evaluative Assessment of Cardiac Events (PEACE)-Prospective AMI Study will enroll 4000 consecutive AMI patients from 53 diverse hospitals across China and follow them longitudinally for 12 months to document their treatment, recovery, and outcomes. Details of patients’ medical history, treatment, and in-hospital outcomes are abstracted from medical charts. Comprehensive baseline interviews are being conducted to characterize patient demographics, risk factors, presentation, and healthcare utilization. As part of these interviews, validated instruments are administered to measure PROs, including quality of life, symptoms, mood, cognition, and sexual activity. Follow-up interviews, measuring PROs, medication adherence, risk factor control, and collecting hospitalization events are conducted at 1, 6, and 12 months after discharge. Supporting documents for potential outcomes are collected for adjudication by clinicians at the National Coordinating Center. Blood and urine samples are also obtained at baseline, 1- and 12-month follow-up. In addition, we are conducting a survey of participating hospitals to characterize their organizational characteristics.

Conclusion:

The China PEACE-Prospective AMI study will be uniquely positioned to generate new information regarding patient's experiences and outcomes after AMI in China and serve as a foundation for quality improvement activities.

[Association between cured meat consumption and risk of colorectal cancer in people with different dietary habits and lifestyles]

OBJECTIVE

To explore the association between the intakes of cured meat and the risk of colorectal cancer, and analyze the role of the interaction between cured meat intake and dietary habit or lifestyle for the risk of colorectal cancer.

METHODS

A well-designed questionnaire were used to collect retrospective information about demography, lifestyle and dietary habit from 400 patients diagnosed with colorectal cancer and 400 controls matched by age and gender. Logistic regression analysis was conducted to examine the possible association between the intake of cured meat and the risk of colorectal cancer. Generalized multifactor dimensionality reduction(GMDR)was used to analyze the interaction between cured meat intake and other dietary habits or lifestyle factors.

RESULTS

Data from conditional logistic regression analysis showed that compared with the people who had <8 times per year of cured meat intake, those had 8-23 times of cured meat intakes(OR=3.480, 95%CI: 2.022-5.991, P<0.001), 24-47 times of cured meat intakes(OR=4.526, 95%CI: 2.553-8.025, P<0.001), ≥48 times of cured meat intakes(OR=5.472, 95% CI: 3.105-9.642, P<0.001)had increased risk of colorectal cancer. There was a multiplied interaction between cured meat intake and pepper intake(OR=0.379, 95% CI: 0.190-0.758, P=0.009). The synergistic effect existed between cured meat intake and pickled vegetable intake; and the antagonism existed between cured meat intake and tea-drinking habit. GMDR analysis showed that interaction among red meat intake, pickled vegetable and cured meat intake on the risk of colorectal cancer might exist(P=0.001).

CONCLUSIONS

With the increase of frequency of cured meat intake, the risk of colorectal cancer increased gradually. The synergistic effect might existed between pickled vegetable intake and cured meat intake. Tea-drinking, pepper intake and cured meat intake might be antagonism in the pathogenesis of colorectal cancer. Red meat intake, pickled vegetable intake and cured meat intake might have combined effect to increase the risk of colorectal cancer.