[Enhancing survival outcomes in stage Ⅲ gastric/esophagogastric junction cancer: a retrospective study of immune checkpoint inhibitors and adjuvant chemotherapy based on real-world data]

Objective: To explore the efficacy of immune checkpoint inhibitors combined with adjuvant chemotherapy in patients with phase III gastric cancer and esophagogastric junction cancer. Methods: This study used a retrospective cohort study method based on real-world data. Clinical data of 403 patients with stage III gastric/esophagogastric junction cancer who underwent gastrectomy followed by adjuvant therapy in the Department of Gastric Surgery at Sun Yat-sen University Cancer Center from January 2020 to December 2023 were retrospectively collected. The study cohort comprised 147 (36.5%) patients with stage IIIA, 130 (32.3%) with stage IIIB, and 126 (31.3%) with stage IIIC gastric/esophagogastric junction cancer. Of them, 15 (3.7%) were HER-2 positive, 25 (6.2%) dMMR, and 22 (5.5%) patients Epstein-Barr virus encoding RNA (EBER) positive. Based on treatment plans, the patients were divided into immune checkpoint inhibitor combined with chemotherapy group (immune therapy group, n=110, 71 males and 39 females, median age 59 years old) and chemotherapy alone group (chemotherapy group, n=293, 186 males and 107 females, median age 60 years old). All patients in the immunotherapy group received immune checkpoint inhibitors targeting the programmed cell death protein-1 (PD-1) and its ligand (PD-L1). Of them, 85 received pembrolizumab, 10 received sintilimab, 8 received tislelizumab, 4 received camrelizumab, 2 received toripalimab, and 1 received pabocizumab. The adjuvant chemotherapy regimens used among the chemotherapy alone group includes SOX regimen (132 cases), XELOX (102 cases), S-1 monotherapy (44 cases), and other regimens (15 cases). The 3-year DFS rate of the two groups was compared, and subgroup analysis was conducted based on different ages, molecular phenotypes, pTNM staging, extranodal infiltration, and tumor length. Results: The median follow-up was 20.5 months (range 3.1~46.3), with a 3-year overall DFS rate of 61.4% for the entire 403 patients. The 3-year DFS rate for the immunotherapy group was 82.7%, higher than the chemotherapy alone group (58.8%), with a statistically significant difference (P=0.021). Multivariate analysis showed that postoperative immunotherapy was a protective factor for DFS (HR=0.352, 95%CI: 0.180~0.685). Subgroup analysis showed that stage IIIC (HR=0.416, 95%CI: 0.184~0.940), aged ≥60 years (HR=0.336, 95%CI: 0.121~0.934) and extranodal invasion (HR=0.378, 95%CI: 0.170~0.839) were associated with benefit from the combined immune adjuvant chemotherapy, while no association was observed for MMR, HER-2 or EBER status. Conclusion: Stage III gastric/esophagogastric junction cancer patients may benefite from postoperative immune checkpoint inhibitor combined with adjuvant chemotherapy in real-world settings.

A spatiotemporal analysis of the association between carbon productivity, socioeconomics, medical resources and cardiovascular diseases in southeast rural China

Introduction

With China's rapid industrialization and urbanization, China has been increasing its carbon productivity annually. Understanding the association between carbon productivity, socioeconomics, and medical resources with cardiovascular diseases (CVDs) may help reduce CVDs burden. However, relevant studies are limited.

Objectives

The study aimed to describe the temporal and spatial distribution pattern of CVDs hospitalization in southeast rural China and to explore its influencing factors.

Methods

In this study, 1,925,129 hospitalization records of rural residents in southeast China with CVDs were analyzed from the New Rural Cooperative Medical Scheme (NRCMS). The spatial distribution patterns were explored using Global Moran's I and Local Indicators of Spatial Association (LISA). The relationships with influencing factors were detected using both a geographically and temporally weighted regression model (GTWR) and multiscale geographically weighted regression (MGWR).

Results

In southeast China, rural inpatients with CVDs increased by 95.29% from 2010 to 2016. The main groups affected were elderly and women, with essential hypertension (26.06%), cerebral infarction (17.97%), and chronic ischemic heart disease (13.81%) being the leading CVD subtypes. The results of LISA shows that central and midwestern counties, including Meilie, Sanyuan, Mingxi, Jiangle, and Shaxian, showed a high-high cluster pattern of CVDs hospitalization rates. Negative associations were observed between CVDs hospitalization rates and carbon productivity, and positive associations with per capita GDP and hospital beds in most counties (p < 0.05). The association between CVDs hospitalization rates and carbon productivity and per capita GDP was stronger in central and midwestern counties, while the relationship with hospital bed resources was stronger in northern counties.

Conclusion

Rural hospitalizations for CVDs have increased dramatically, with spatial heterogeneity observed in hospitalization rates. Negative associations were found with carbon productivity, and positive associations with socioeconomic status and medical resources. Based on our findings, we recommend low-carbon development, use of carbon productivity as an environmental health metric, and rational allocation of medical resources in rural China.

Spatial patterns and the associated factors for breast cancer hospitalization in the rural population of Fujian Province, China

BACKGROUND

Despite the known increasing incidence of breast cancer in China, evidence on the spatial pattern of hospitalization for breast cancer is scarce. This study aimed to describe the disparity of breast cancer hospitalization in the rural population of Southeast China and to explore the impacts of socioeconomic factors and heavy metal pollution in soil.

METHODS

This study was conducted using the New Rural Cooperative Medical Scheme (NRCMS) claims data covering 20.9 million rural residents from 73 counties in Southeast China during 2015-2016. The associations between breast cancer hospitalization and socioeconomic factors and soil heavy metal pollutants were evaluated with quasi-Poisson regression models and geographically weighted Poisson regressions (GWPR).

RESULTS

The annual hospitalization rate for breast cancer was 101.40/100,000 in the studied area and the rate varied across different counties. Overall, hospitalization for breast cancer was associated with road density (β = 0.43, P = 0.02), urbanization (β = 0.02, P = 0.002) and soil cadmium (Cd) pollution (β = 0.01, P = 0.02). In the GWPR model, a stronger spatial association of Cd, road density and breast cancer hospitalization was found in the northeast regions of the study area while breast cancer hospitalization was mainly related to urbanization in the western regions.

CONCLUSIONS

Soil Cd pollution, road density, and urbanization were associated with breast cancer hospitalization in different regions. Findings in this study might provide valuable information for healthcare policies and intervention strategies for breast cancer.

Spatial distribution and influencing factors of thyroid cancer hospitalization rate among rural residents in Fujian Province, China from 2012 to 2016

This study aimed to explore the spatial distribution and influencing factors of thyroid cancer hospitalization rates in Fujian Province from 2012 to 2016. Hospitalization reimbursement records for thyroid cancer were obtained from 2025 hospitals in Fujian Province from 2012 to 2016. The Moran's I method was used for spatial autocorrelation analysis and to further draw a spatial cluster map in Fujian. Geographic detectors were used to explore the effect of risk factors on spatial heterogeneity of inpatient service utilization for thyroid cancer. The study showed that there was obvious temporal and spatial heterogeneity in the utilization rate of inpatient services for thyroid cancer in Fujian Province, which were mainly concentrated in Fuzhou, with Lianjiang County as the center, and the gathering area involves 26 counties and cities. Among a variety of environmental factors, air quality index (AQI) (q = 0.481), carbon sequestration (q = 0.161), and carbon emissions (q = 0.155) were the main factors affecting the hospitalization rates. AQI and carbon emissions were generally positively correlated with hospitalization rates, and carbon sequestration was negatively correlated. After the interaction of the two factors, the interpretation of the hospitalization rate was enhanced. The obvious spatial heterogeneity will help the relevant departments to adjust measures to local conditions and allocate medical resources rationally to ease the pressure of seeking medical attention in high-demand areas.

The spatiotemporal correlation of PM2.5 concentration on esophageal cancer hospitalization rate in Fujian province of China

This paper aimed to explore the correlation between PM_2.5 concentration and hospitalization rate of esophageal cancer in Fujian province, and tried to find out the accurate lag effect between PM_2.5 and hospitalization rate in 70 counties from the linear and nonlinear aspects. We extracted inpatients data of esophageal cancer from the New Rural Cooperative Medical Scheme (NRCMS) database and air pollutant PM_2.5 grid data published by the atmospheric composition analysis group. The study showed that the hospitalization rate of esophageal cancer presented spatial aggregation in 70 counties of Fujian province. Southeast urban agglomerations had high hospitalization rates, while central and western regions had low hospitalization rates. The study found that the spatial distribution of the hospitalization rate of esophageal cancer in 2016 was not consistent with that of the PM_2.5 concentration in the same year. The concentration of PM_2.5 in 2003 and 2004 had the strongest correlation with the hospitalization rate of esophageal cancer in 2016, with Pearson correlation coefficient r value of - 0.365 and Geodetector q-statistic value of 0.148 (p < 0.05). Our findings showed that there existed a 13-year lag period of air pollutant PM_2.5 on the esophageal cancer hospitalization rate, which can provide helpful guidance in the early screening strategy of esophageal cancer in Fujian. The research progress of this paper will help to understand the lag period of the impact of air pollutants on the hospitalization rate of esophageal cancer, provide valuable information for the prevention and treatment strategy of esophageal cancer in Fujian province, and provide relevant experience for alike regions.

Engineering a High-Voltage Durable Cathode/Electrolyte Interface for All-Solid-State Lithium Metal Batteries via In Situ Electropolymerization

Poly(ethylene oxide) (PEO)-based polymer electrolytes have been widely studied as a result of their flexibility, excellent interface contact, and high compatibility with a lithium metal anode. Owing to the poor oxidation resistance of ethers, however, the PEO-based electrolytes are only compatible with low-voltage cathodes, which limits their energy density. Here, a high-voltage stable solid-state interface layer based on polyfluoroalkyl acrylate was constructed via in situ solvent-free bulk electropolymerization between the LiNi_0.8Mn_0.1Co_0.1O₂ (NCM811) cathode and the PEO-based solid polymer electrolyte. The electrochemical oxidation window of the as-synthesized electrolyte was therefore expanded from 4.3 V for the PEO-based matrix electrolyte to 5.1 V, and the ionic conductivity was improved to 1.02 × 10^-4 S cm^-1 at ambient temperature and 4.72 × 10^-4 S cm^-1 at 60 °C as a result of the improved Li⁺ migration. This fabrication process for the interface buffer layer by an in situ electrochemical process provides an innovative and universal interface engineering strategy for high-performance and high-energy-density solid-state batteries, which has not been explicitly discussed before, paving the way toward the large-scale production of the next generation of solid-state lithium batteries.

Spatial Analysis and Comparison of the Economic Burden of Common Diseases: An Investigation of 5.7 Million Rural Elderly Inpatients in Southeast China, 2010-2016

Background: As China embraced an aging society, the burden of age-related diseases had increased dramatically. Knowledge about spatial distribution characteristics of disease burden and the influencing factors of medical expenditure is of great significance to the formulation of health policies. However, related research in rural China is still insufficient.

Methods: A total of 5,744,717 records of hospitalized rural elderly in southeast China were collected from 2010 to 2016. We described the temporal trends of hospitalization medical expenditure and the prevalence of catastrophic health expenses (CHE) in the rural elderly by common diseases. Then, geographical information tools were used for visualization of geographic distribution patterns of CHE, the ordinary least squares methods (OLS) and geographically weighted regression (GWR) were employed to examine the influencing factors of medical expenditure.

Results: The number of CHE hospitalizations and the total number of hospitalizations for the rural elderly people increased by 2.1 times and 2.2 times, respectively, from 2010 to 2016. Counties with a high prevalence of CHE were clustered in the eastern coastal area (Moran's I = 0.620, P < 0.001, General G < 0.001, P < 0.001). Unspecified transport accidents, cardiovascular disease, and essential hypertension were the top causes of CHE in the rural elderly. Adequate hospital beds (P < 0.05) and reasonable utilization and distribution of town-level (P < 0.001) and county-level hospitals (P < 0.001) may help reduce medical expenditures.

Conclusions: In the context of an aging society, the disease burden for the elderly in rural areas should arouse more attention. These findings highlight the importance of age-related disease prevention and the rational allocation of medical resources in rural areas.

A Prelithiation Separator for Compensating the Initial Capacity Loss of Lithium-Ion Batteries

Lithium loss during the initial charge process inevitably reduces the capacity and energy density of lithium-ion batteries. Cathode additives are favored with respect to their controllable prelithiation degree and scalable application; however, the insulating nature of their delithiation products retards electrode reaction kinetics in subsequent cycles. Herein, we propose a prelithiation separator by modifying a commercial separator with a Li₂S/Co nanocomposite to compensate for the initial capacity loss. The Li₂S/Co coating layer extracts active lithium ion during the charge process and shows a delithiation capacity of 993 mA h g^-1. When paired with a LiFePO₄|graphite full cell, the reversible capacity is increased from 112.6 to 150.3 mA h g^-1, leading to a 29.5% boost in the energy density. The as-prepared pouch cell also demonstrates a stable cycling performance. The excellent electrochemical performance and the scalable production of the prelithiation separator reveal its great potential in lithium-ion battery industry application.

Polycationic Polymer Layer for Air-Stable and Dendrite-Free Li Metal Anodes in Carbonate Electrolytes

The short cycle life and safety concerns caused by uncontrollable dendrite growth have severely hindered the commercialization of lithium metal batteries. Here, a polycationic and hydrophobic polymer protective layer fabricated by a scalable tape-casting method is developed to enable air-stable, dendrite-free, and highly efficient Li metal anodes. The polymeric cations of poly(diallyl dimethyl ammonium) (PDDA) provide an electrostatic shielding effect that unifies Li⁺ flux at the surface of the Li anode and promotes a homogeneous Li plating, while the bis(trifluoromethanesulfonyl)imide (TFSI) anions bring hydrophobic characteristics and improve moisture stability. The accumulated TFSI anions by the polycationic film also facilitate the formation of a stable solid electrolyte interphase (SEI). Steady Li plating/stripping in the carbonate electrolyte can be achieved under a high areal capacity of 10 mAh cm^-2 for 700 h with Li utilization efficiency up to 51.6%. LiNi_0.8 Mn_0.1 Co_0.1 O₂ and LiFePO₄ cells using the modified anode exhibit much improved electrochemical performance compared with the bare Li counterpart. Moreover, ultrasonic imaging shows no gas generation in the modified Li/LiFePO₄ pouch cell. Mechanism investigation demonstrates the stable SEI and homogeneous Li deposition derived by the polycationic layer.

Electrochemical (bio) sensors go green

Electrochemical (bio) sensors are now widely acknowledged as a sensitive detection tool for disease diagnosis as well as the detection of numerous species of pharmaceutical, clinical, industrial, food, and environmental origin. The term 'green' demonstrates the development of electrochemical (bio) sensing platforms utilizing biodegradable and sustainable materials. Development of green sensing platforms is one of the most active areas of research minimizing the use of toxic/hazardous reagents and solvent systems, thereby further reducing the production of chemical wastes in sensor fabrication. The present review includes green electrochemical (bio) sensors which are based on firstly, green sensors comprising natural and non-hazardous materials (e.g., paper/clay/zeolites/biowastes), secondly sensors based on nanomaterials synthesized by green methods and lastly sensors constituting green solvents (e.g., ionic liquids/deep eutectic solvents). Electrochemical performances of such green sensors and their benefits such as biodegradability, non-toxicity, sustainability, low-cost, sensitive surfaces, etc. Have been discussed for quantification of various target analytes. Associated challenges, possible solutions, and opportunities towards fabricating green electrochemical sensors and biosensors have been provided in the conclusion section.

Construct an Ultrathin Bismuth Buffer for Stable Solid-State Lithium Metal Batteries

LAGP (Li_1.5Al_0.5Ge_0.5P₃O₁₂) is a promising solid-state electrolyte (SSE) for all solid-state lithium-ion batteries (ASS-LIBs) with its favorable lithium ionic conductivity and good performance on inhibiting lithium dendrite. However, the ultrahigh interfacial resistance between lithium metal anode and LAGP SSEs greatly hinders its application. In this work, a thin film of metallic Bi was sputtered on LAGP to improve the chemical/physical properties of the Li/SSE interface. It is found that the Bi buffer not only inhibits the unfavorable reaction between LAGP SSEs and Li metal, but also improved their compatibility. As a result, the Li/LAGP interfacial resistance was effectively reduced from 2255.6 to 92.8 Ω cm² at 30 °C. Furthermore, a good performance solid state full cell with a LiFePO₄ cathode had been demonstrated. This work provides an effective avenue to address the interfacial challenges between Li metal and LAGP SSE.

Coordination induced electron redistribution to achieve highly reversible Li-ion insertion chemistry in metal-organic frameworks

Herein, the coordination-induced increase in the electron density of fused C6 rings in MOFs as high performance anode materials for Li+ ion batteries is described. Zn-PTCA is able to deliver a high specific capacity of 700 mA h g-1 at 50 mA g-1 and exhibits excellent cycle performance over 1100 cycles and good rate capability.

Comparison of Both Sides for Retroperitoneal Laparoscopic Donor Nephrectomy: Experience From a Single Center in China

BACKGROUND

Laparoscopic donor nephrectomy (LDN) has gradually become the main approach to obtain live donor kidneys. However, the shorter right renal vein limits its wider application. The aim of this study was to compare the outcomes of left- and right-side retroperitoneal LDN.

METHODS

We reviewed the perioperative data of 527 consecutive donors receiving retroperitoneal pure LDN with a new method at our center between April 2009 and April 2014. The patients were divided into group A (the first 100 patients) and group B (the remaining 427 patients). A total of 423 cases of left donor surgery and 104 cases of right donor surgery were compared. The comparison of the laterality of LDN was also performed between group A and group B.

RESULTS

This is currently the largest case series of LDN in our country. Although right-side LDN patients had longer operation time and a slightly higher incidence of intraoperative complications compared with left-side LDN patients, the operation time was shorter in both the groups compared with previous reports. In group B, patients undergoing right-side LDN had longer operation time and more frequent complications. Once the learning curve of 100 cases was completed, the incidence of complications and operation time were greatly reduced in both sides for LDN. There was no significant difference in the serum creatinine levels in recipients at 6 months of follow-up.

CONCLUSIONS

Despite a slightly higher incidence of complications and longer operation time, right-side LDN can achieve equally safe and effective transplantation outcomes. This expands the source of potential donor kidneys.

Efficient androst-1,4-diene-3,17-dione production by co-expressing 3-ketosteroid-Δ1 -dehydrogenase and catalase in Bacillus subtilis

AIMS

3-ketosteroid-Δ¹ -dehydrogenase (KSDD), a flavin adenine dinucleotide (FAD)-dependent enzyme involved in sterol metabolism, specifically catalyses the conversion of androst-4-ene-3,17-dione (AD) to androst-1,4-diene-3,17-dione (ADD). However, the low KSDD activity and the toxic effects of hydrogen peroxide (H₂ O₂ ) generated during the biotransformation of AD to ADD with FAD regeneration hinder its application on AD conversion. The aim of this work was to improve KSDD activity and eliminate the toxic effects of the generated H₂ O₂ to enhance ADD production.

METHODS AND RESULTS

The ksdd gene obtained from Mycobacterium neoaurum JC-12 was codon-optimized to increase its expression level in Bacillus subtilis, and the KSDD activity reached 12·3 U mg^-1 , which was sevenfold of that of codon-unoptimized gene. To improve AD conversion, catalase was co-expressed with KSDD in B. subtilis 168/pMA5-ksdd^opt -katA to eliminate the toxic effects of H₂ O₂ generated during AD conversion. Finally, under optimized bioconversion conditions, fed-batch strategy was carried out and the ADD yield improved to 8·76 g l^-1 .

CONCLUSIONS

This work demonstrates the potential to improve enzyme activity by codon-optimization and eliminate the toxic effects of H₂ O₂ by co-expressing catalase.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study showed the highest ADD productivity ever reported and provides a promising strain for efficient ADD production in the pharmaceutical industry.

Conversion From Calcineurin Inhibitors to Mammalian Target-of-Rapamycin Inhibitors in Heart Transplant Recipients: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

Conversion from calcineurin inhibitors (CNIs) to mammalian target-of-rapamycin inhibitors (mTORi) was systematically evaluated in heart transplant recipients (HTRs) for the first time.

METHODS

MEDLINE (PUBMED), EMBASE, Cochrane Library, and clinical trial registries were searched comprehensively. After screening for eligibility, the randomized controlled trials (RCTs) comparing continuation of CNI with conversion to mTORi therapy underwent review, quality assessment, and data extraction. Outcomes analyzed including creatinine clearance, serum creatinine level, rejection, adverse effects, and triglyceride levels were expressed as mean differences (MDs) or as risk ratios (RRs) with 95% confidence intervals (CIs).

RESULTS

This is the first systematic review evaluating converting from CNI to mTORi therapy in HTRs. A total of 4 RCTs (231 HTRs, 117 vs 114) were included in our analysis. Patients converted to mTORi had a higher creatinine clearance (MD, 19.31; 95% CI [11.16, 27.46]; P < .00001) and lower serum creatinine levels (MD, -0.15; 95% CI [-0.25, -0.05]; P = .002). Patients converted to mTORi had a significantly higher occurrence of adverse effects, which included skin diseases, gastrointestinal side effects, bone marrow suppression, and infections. There was no significant difference between the 2 groups regarding graft rejection and triglyceride levels (RR, 2.61; 95% CI [0.08, 81.25]; P = .58; MD, 22.89; 95% CI [-21.86, 67.63]; P = .32).

CONCLUSIONS

Conversion from CNI to mTORi therapy may improve the renal function in HTRs, but the patients may suffer from a high incidence of mTORi-associated adverse events. Therefore, conversion to mTORi must be carefully assessed for the benefits and risks.

Identification and characterization of a novel 2,3-butanediol dehydrogenase/acetoin reductase from Corynebacterium crenatum SYPA5-5

Acetoin and 2,3-butanediol are widely used in the chemical and pharmaceutical industries. The enzyme, 2,3-butanediol dehydrogenase/acetoin reductase (2,3-BDH/AR), plays a significant role in the microbial production of acetoin and 2,3-butanediol by catalysing a reversible reaction between acetoin and 2,3-butanediol. To date, a 2,3-BDH has not been characterized from Corynebacterium crenatum. 2,3-BDH was cloned from Coryne. crenatum SYPA5-5 and expressed in Escherichia coli BL21. Sequence analysis suggested that the 2,3-BDH from Coryne. crenatum SYPA5-5 belongs to the short-chain dehydrogenase/reductase superfamily. Its maximum specific activity was obtained at 35°C, however, it became very unstable when the temperature was above 35°C. Its optimal pH was 4·0 for reduction reaction and 10·0 for oxidation reaction. The 2,3-BDH activity was increased to some extent by Ca(2+) , Mg(2+) , Zn(2+) and Mn(2+) ions. In particular, Ca(2+) induced about 1·5-fold increase. The value of kcat /Km for diacetyl and acetoin are higher than for 2,3-butanediol indicating that 2,3-BDH can easily reduce diacetyl or acetoin to 2,3-butanediol under lower pH conditions. The characteristics of 2,3-BDH from Coryne. crenatum SYPA5-5 will give guide to further studies for the production of acetoin and 2,3-butanediol with engineered Coryne. crenatum SYPA5-5.

SIGNIFICANCE AND IMPACT OF THE STUDY

Acetoin and 2,3-butanediol are commonly used as platform chemicals and widely used in pharmaceutical industries. 2,3-butanediol dehydrogenase/acetoin reductase (2,3-BDH/AR) plays a significant role in the microbial production of acetoin and 2,3-butanediol. In this study, 2,3-BDH was cloned from Corynebacterium crenatum SYPA5-5, was expressed in Escherichia coli BL21 and characterized with respect to the optimal temperature, pH, substrate specificity and kinetics. The results will guide further studies in Coryne. crenatum SYPA5-5 for the production of acetoin and 2,3-butanediol.

Short-term therapeutic drug monitoring of mycophenolic acid reduces infection: a prospective, single-center cohort study in Chinese living-related kidney transplantation

BACKGROUND

The role of therapeutic drug monitoring (TDM) of mycophenolic acid (MPA) in kidney transplant recipients (KTRs) is not clear. We performed a prospective cohort study to evaluate the efficiency of MPA TDM in the Chinese population.

METHODS

A total of 183 living-related KTRs were studied; 101 KTRs received controlled-dose mycophenolate mofetil (MMF) (the CD group), and 82 patients received fixed-dose MMF (the FD group). MPA exposure was measured at days 3, 7, 14, and 30 in the CD group, and at day 30 in the FD group. The primary endpoint was treatment failure (a composite of acute rejection, graft loss, death, or MMF discontinuation) at 12 months post transplantation.

RESULTS

In the CD group, with a starting MMF dose of 2 g/day, approximately 35% of patients had high MPA levels, which were >60 mg × h/L, and mean MPA levels were 59.17 mg × h/L and 61.38 mg × h/L for the CD and FD groups, respectively (P = 0.588). After adjusting MMF dose, MPA exposures in the CD group at day 30 were lower than those in the FD group at day 30 (54.06 vs. 61.38, P = 0.004). At month 12, the CD group had fewer infections (16.8% vs. 31.7%, P = 0.018) with no difference in treatment failure, acute rejection, diarrhea, or anemia.

CONCLUSIONS

KTRs can benefit from short-term TDM of MPA in reducing infection, without increasing acute rejection.

Clinicopathological and prognostic significance of α5β1-integrin and MMP-14 expressions in colorectal cancer

The purpose of this study was to evaluate the association of expression level of α5β1-integrin and MMP-14 with clinicopathologic features and prognosis in colorectal cancer (CRC). The expressions of α5β1-integrin and MMP-14 in normal colorectal mucosa and CRC tissue were detected with immunohistochemistry. We estimated the five-year survival rate by the Kaplan-Meier method. The positive expressions rates of α5β1-integrin and MMP-14 in CRC tissue were 60.6% and 63.3% respectively, and there were significant differences on their positive expression rates between in CRC tissue and in normal colorectal mucosa(P<0.05). The expression rates of α5β1-integrin and MMP-14 in patients with poor histological differentiation, lymph node metastasis and high clinical staging were heightened. There was a significant difference (P<0.05) on the five-year survival rate for α5β1-integrin expression, which was 44.6% in positive groups and 75.5% in negative groups. And there was a significant difference (P<0.05) on the five-year survival rate for MMP-14 expression, which was 48.2% in positive group and 73.1% in negative group. The expression of α5β1-integrin and MMP-14 is correlated with the progression and metastasis of CRC, and α5β1-integrin and MMP-14 may be used as prognostic markers in CRC.

Ubiquitin pathway and ovarian cancer

The ubiquitin-proteasome pathway is a common cellular process in eukaryotic tissue. Ubiquitin binds to proteins and tags them for destruction; this tagging directs proteins to the proteosome in the cell that degrades and recycles unneeded proteins. The ubiquitin-proteasome pathway plays an important role in the regulation of cellular proteins with respect to cell cycle control, transcription, apoptosis, cell adhesion, angiogenesis, and tumour growth. This review article discusses the various ways that the ubiquitin pathway is involved in ovarian cancer, such as modulating the ovarian-cancer-related gene BRCA1 and tumour suppressor p53, and interfering with the erk pathway, the cyclin-dependent cell cycle regulation process, and ERBB2 gene expression.

Engineered Saccharomyces cerevisiae that produces 1,3-propanediol from D-glucose

AIMS

Saccharomyces cerevisiae is a safe micro-organism used in fermentation industry. 1,3-Propanediol is an important chemical widely used in polymer production, but its availability is being restricted owing to its expensively chemical synthesis. The aim of this study is to engineer a S. cerevisiae strain that can produce 1,3-propanediol at low cost.

METHODS AND RESULTS

By using D-glucose as a feedstock, S. cerevisiae could produce glycerol, but not 1,3-propanediol. In this study, we have cloned two genes yqhD and dhaB required for the production of 1,3-propanediol from glycerol, and integrated them into the chromosome of S. cerevisiae W303-1A by Agrobacterium tumefaciens-mediated transformation. Both genes yqhD and dhaB functioned in the engineered S. cerevisiae and led to the production of 1,3-propanediol from D-glucose.

CONCLUSION

Saccharomyces cerevisiae can be engineered to produce 1,3-propanediol from low-cost feedstock D-glucose.

SIGNIFICANCE AND IMPACT OF THE STUDY

To our knowledge, this is the first report on developing S. cerevisiae to produce 1,3-propanediol by using A. tumefaciens-mediated transformation. This study might lead to a safe and cost-efficient method for industrial production of 1,3-propanediol.

Human 8-oxoguanine DNA glycosylase increases resistance to hyperoxic cytotoxicity in lung epithelial cells and involvement with altered MAPK activity

It is unknown whether base excision DNA repair (BER) proteins interact with mitogen-activated protein kinases (MAPK) under oxidation. Here, we explored roles of BER proteins in signaling transduction involving MAPK during hyperoxia. We demonstrated that ERK1/2 phosphorylation in A549 cells was increased in 95% O₂. p38 activity in A549 cells was also increased by exposure to 95% O₂. To evaluate regulatory roles of MAPK, we have transduced A549 cells and primary alveolar epithelial type II cells (AECII) to overexpress 8-oxoguanine DNA glycosylase (hOgg1). Overexpression of hOgg1 reduced hyperoxic toxicity in A549 and AECII cells. Furthermore, protection by BER against hyperoxia appeared to involve an upregulation of ERK1/2 and downregulation of p38. These observations demonstrate, for the first time, that reduction of hyperoxic toxicity by BER proteins may be involved with MAPK activity, thereby impacting cell survival. Furthermore, our studies suggest that modulation of MAPK may be used in combination with BER proteins to counteract hyperoxic toxicity.

Crystallization of a calcium-binding EGF-like domain

Crystals of a calcium-binding epidermal growth factor (EGF)-like domain of human clotting factor IX suitable for X-ray diffraction analysis have been obtained by vapour diffusion (sitting drop) against 48% PEG 400. The crystals belong to the tetragonal space group P4(3)2(1)2, with unit-cell dimensions a = b = 40.3, c = 98.2 A. The crystals diffract beyond 1.5 A resolution and are relatively stable in the X-ray beam. This is the first reported crystallization of a calcium-binding EGF-like domain.

Purification, crystallization and preliminary X-ray analysis of human pirin

Pirin is a novel highly conserved nuclear protein, but very little is known about its cellular function. Human pirin has been cloned, expressed, purified and crystallized using PEG as precipitant. The crystal belongs to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 42.3, b = 67.0, c = 107.3 A, alpha = beta = gamma = 90 A. It contains one molecule per asymmetric unit and diffracts to 2.0 A under cryoconditions (100 K) using an in-house Cu rotating-anode X-ray generator.

Biochemical and biophysical analysis of heptad repeat regions from the fusion protein of Menangle virus, a newly emergent paramyxovirus

Menangle virus is a novel paramyxovirus isolated in Australia in 1997, but its classification position has not yet been finally settled. Here by using a computational program, LearnCoil-VMF, we determined the heptad repeat (HR) regions (HR1 and HR2) of Menangle virus F protein. Subsequently the HR1 and HR2 peptides were expressed as a single chain (named 2-Helix) connected by a six amino-acid linker as a GST fusion protein with an E. coli in vitro expression system. The GST-removed purified 2-Helix protein could form a stable trimer in vitro judging by gel-filtration and chemical cross-linking. CD spectra showed that the 2-Helix protein had a high percentage of alpha-helix and was very thermo-stable. Crystals of the 2-Helix protein preparations have been obtained in many conditions with hanging-drop diffusion method. These results indicated that Menangle virus has the common features of the fusion protein for other paramyxoviruses and should adopt a similar fusion mechanism to other members. As the HR regions of Menangle virus F protein could form stable six-helix bundle coiled coil structure, they should be used as drug target for the design of fusion inhibitors, as successfully used for other parmyxoviruses. This is especially relevant to such a newly emergent virus with zoonotic potentials.

Engineering substrate recognition in catalysis by cytochrome P450cam

We have a continuing interest in applying the current knowledge of cytochrome P450cam substrate recognition to engineer the enzyme for the biotransformation of unnatural substrates with the long-term aim of applications in the synthesis of fine chemicals and bioremediation of environmental contaminants. Comparisons of the structure of target substrates with that of camphor, the natural substrate, led to the design of active-site mutants with greatly enhanced activity for the oxidation of chlorinated benzenes and selectivity of (+)-alpha-pinene oxidation. The crystal structures of the F87W/Y96F/V247L mutant with 1,3,5-trichlorobenzene or (+)-alpha-pinene bound have revealed the enzyme-substrate contacts and provided insights into the activity and selectivity patterns. The structures have also provided a novel basis for further engineering of P450cam for increased activity in the oxidation of the highly inert pentachlorobenzene and hexachlorobenzene, and increased selectivity of (+)-alpha-pinene oxidation.

Crystallization of the N-terminal domain of DFF45: the mutual chaperone mechanism is challenged

DNA fragmentation factor 45 (DFF45) regulates DNase DFF40 as its inhibitor and chaperone. It was reported that the N-terminal domain (NTD) of DFF45 alone is disordered and DFF40 is necessary as a mutual chaperone for the folding of NTD. However, here we reported the crystallization of DFF45 NTD. These crystals diffract to 9A using a synchrotron radiation source. In spite of the low resolution, the demonstration of crystal formation indicates that DFF45 NTD itself is not unstructured, which strongly questions the mutual chaperone speculation about DFF45 and DFF40.

Purification, crystallization and X-ray analysis of swine vesicular disease virus

Swine vesicular disease virus (SVDV) is the etiological agent of swine vesicular disease, a highly contagious disease in pigs, and is related to coxsackie B virus. Crystalline arrays of SVDV can be observed in the cytoplasm of cells 4.5 h after inoculation to porcine kidney cells (IBRS-2 cells). Crystals of the JX/78 strain of SVDV were obtained from virus in two wells of crystallization conditions and present preliminary X-ray data to 3.6 A resolution.

Crystallization and preliminary x-ray crystallographic studies of trichosanthin delta C7

Trichosanthin (TCS) is a type I ribosome-inactivating protein (RIP) which possesses rRNA N-glycosidase activity. TCS has various pharmacological properties. It is possible to reduce the antigenicity of TCS by deleting up to seven C-terminal residues of TCS (TCS-C7) with minimal effect on its activity. TCS-C7 has been crystallized and the crystal diffracted to 1.8 A. It belongs to space group P2(1), with unit-cell parameters a=71.6A, b=74.4A, c=87.6A, beta=97.0 degrees. It is given that there are four molecules per asymmetric unit.

Preliminary X-ray crystallographic analysis of ciliate Euplotes octocarinatus release factor eRF1a

eRF1a, one of the class-I release factors from ciliate Euplotes octocarinatus, has been crystallized by the vapor-diffusion method using polyethylene glycol 4000 as the precipitant at pH 7.5. The crystal belongs to space group P2(1) and the unit-cell parameters are a=90.4, b=107.9, c=114.8A, beta=94.2 degrees. There appear to be four eRF1a molecules in the asymmetric unit.

Crystallization and preliminary X-ray crystallographic studies of a macromolecular antitumour antibiotic, C1027

C1027 is a macromolecular antitumour antibiotic produced by Streptomyces globispourus C1027 and consists of an apoprotein and a non-protein labile chromophore. Little is known about how the thermally unstable chromophore is stabilized by the apoprotein. The purified C1027 was monodisperse according to dynamic light-scattering measurements and crystallized in two different crystal forms from two different starting conditions using the vapour-diffusion method. Condition I yielded hexagonal prism crystals having space group P3(1)/P3(2) and unit-cell parameters a = b = 66.8, c = 55.4 A. Diffraction data were collected to 2.1 A resolution using an in-house Rigaku rotating Cu anode X-ray generator. Another condition produced rod-like crystals with space group P3(1)21/P3(2)21 and unit-cell parameters a = b = 55.15, c = 55.87 A. A data set to 1.8 A resolution was collected from a rod-like crystal using a MAR CCD detector at the SRS synchrotron source.

Crystallization and preliminary X-ray analysis of a Trx domain of human thioredoxin-like protein

The Trx domain of human thioredoxin-like protein has been purified and crystallized using ammonium sulfate as precipitant. The crystal belongs to space group C2, with unit-cell parameters a = 87.5, b = 48.5, c = 29.8 A, beta = 99.59 degrees. It has one molecule per asymmetric unit and diffracts beyond 2.2 A under cryoconditions (100 K) using an in-house Cu rotating-anode X-ray generator.

Crystallization and preliminary X-ray crystallographic analysis of native and selenomethionyl recombinant tabtoxin-resistance protein complexed with acetyl-coenzyme A

Tabtoxin-resistance protein (TTR), an acetyltransferase from Pseudomonas syringae pv. tabaci, was overexpressed in Eschericha coli M15 and the TTR fusion protein complexed with acetyl-coenzyme A (AcCoA) was purified and crystallized. Diffraction data were collected to 3.0 A resolution in-house and the crystal was found to belong to space group P2(1), with unit-cell parameters a = 47.6, b = 66.6, c = 53.5 A, beta = 104.3 degrees. Furthermore, a selenomethionine (SeMet) TTR fusion protein derivative was overexpressed in the same expression system and its complex with AcCoA was purified in a reductive environment. The SeMet TTR derivative crystallized in two forms: the first was identical to that observed for native crystals and the second belonged to space group C2, with unit-cell parameters a = 101.7, b = 45.6, c = 84.2 A, beta = 105.8 degrees. Data from the P2(1) crystal form were collected in-house to 2.3 A resolution. Subsequently, three different wavelength data sets of the C2 crystal form to 1.55 A resolution were collected at the Advanced Photon Source at Argonne National Laboratory.

Evidence for involvement of the neural pathway containing the peripheral vagus nerve, medullary visceral zone and central amygdaloid nucleus in neuroimmunomodulation

It is now evident that a bidirectional communication network exists between the central nervous system (CNS) and immune system (IS). However, the way in which the IS passes inform to the brain is not quite clear.In the present study, one of the neural pathways involved in the cytokine-to-brain communication was investigated in the rat. This pathway starts at the vagal nerve projecting to the medullary visceral zone (MVZ), an arc-shape band from the dorsomedial to ventrolateral area in the middle-caudal segment of the medulla oblongata, and terminates at the central amygdaloid nucleus (Ce) which receives projections from large catecholaminergic neurons in the MVZ. Animals were randomly divided into two experimental groups. Triple-labeling was used in Group I animals to combine wheat germ aggulutinin-conjugated horseradish peroxidase (WGA-HRP) retrograde tracing with anti-Fos and anti-tyrosine hydroxylase (TH) immunostaining. WGA-RP was stereotaxically injected into the unilateral Ce of the animals and, after a survival period of 48 h, intraperitoneal (IP) injection of lipopolysaccharide (LPS) was performed. Seven kinds of labeled neurons were observed in the MVZ, namely, HRP-, Fos- or TH-singly-labeled neurons; Fos/HRP-, Fos/TH- or HRP/TH-doubly-labeled neurons; and Fos/HRP/TH-triply-labeled neurons. As for Group II animals, bilateral subdiaphragmatic vagotomy (SDV) or sham operation was performed, followed 4 weeks later by IP injection of LPS. The number of Fos-positive neurons within the Ce and MVZ was significantly lower (P<0.01) in rats having SDV when compared with those receiving sham operation. Our results suggest that part of the peripheral immune information can be conveyed through the vagus to the catecholaminergic neurons in the MVZ, where it is transported to the Ce. The MVZ is a neural relay station in the immune-to-brain communication and might play a significant role in neuroimmuno-modulation via the vagus-MVZ-Ce pathway.

Preliminary X-ray crystallographic analysis of a Ca2+-binding protein human S100A1

S100A1, a Ca(2+)-binding protein from the S100 protein family, has been crystallized by the vapour-diffusion method using polyethylene glycol 4000 as the precipitant at pH 8.5. The crystal belongs to space group P6(3). The unit-cell parameters are a = b = 57.3, c = 104.7 A. There appear to be two S100A1 molecules in the asymmetric unit. The crystals were stable during exposure to X-rays and diffract to 2.6 A resolution in-house.

A new implementation of the molecular replacement method using a six-dimensional Patterson vector search

The current molecular replacement programs are primarily implemented in reciprocal space. In this paper a new implementation in direct (real) space is proposed by matching the model atomic vectors with the vectors in the Patterson vector space using a six-dimensional exhaustive search method. It is shown that this implementation can find the correct rotations and translations of alpha helices in a myoglobin crystal structure using experimental diffraction data at 2 A resolution. A comparison with previous Patterson vector search methods is discussed.

The experimental study on the effect calcitonin gene-related peptide on bone resorption mediated by interleukin-1

To investigate the effect of calcitonin gene-related peptide (CGRP) on bone resorption mediated by interleukin-1 beta(IL-1 beta) in vitro, the osteoclasts isolated from the long bones of newborn SD rats were co-cultured with osteoblasts on ivory slices placed in 24-well plates. 24 h later, conditioned media containing CGRP and/or IL-1 beta were added to the wells respectively, and continued culturing for 48 h. After the cells were stripped off by ultrasonication, the ivory slices were stained in toludine blue. The number and the total area of resorption lacunae on each slice were measured by computer imaging analysis system. Our results showed that IL-1 beta significantly stimulated bone resorption, but CGRP inhibited the effect mediated by IL-1 beta in a dose-dependent manner. It is suggested that CGRP may inhibit osteoclastic bone resorption through two ways: One is that CGRP functions directly on osteoclasts to block their activation; the other is that CGRP regulates the release of cytokines by osteoblasts and indirectly affects the function of osteoclasts.

Deriving robust operating rules for the interim control of the Kirazdere reservoir

A methodology is developed for deriving robust operating rules for the interim control of a multipurpose reservoir. The methodology includes the generation of policies using optimisation models, the derivation of robust operating rules using artificial neural networks and the evaluation of the identified policies through simulation. The approach developed is demonstrated through an application to the Kirazdere Reservoir located on the Kiraz River in Turkey.