Data mining and safety analysis of traditional immunosuppressive drugs: a pharmacovigilance investigation based on the FAERS database.

OBJECTIVE: The purpose of this study aimed to explore the new and serious adverse events(AEs) of Tacrolimus(FK506), cyclosporine(CsA), azathioprine(AZA), mycophenolate mofetil(MMF), cyclophosphamide(CTX) and methotrexate(MTX), which have not been concerned. METHODS: The FAERS data from January 2016 and December 2022 were selected for disproportionality analysis to discover the potential risks of traditional immunosuppressive drugs. RESULTS: Compared with CsA, FK506 has more frequent transplant rejection, and is more related to renal impairment, COVID-19, cytomegalovirus infection and aspergillus infection. However, CsA has a high infection-related fatality rate. In addition, we also found some serious and rare AE in other drugs which were rarely reported in previous studies. For example, AZA is closely related to hepatosplenic T-cell lymphoma with high fatality rate and MTX is strongly related to hypofibrinogenemia. CONCLUSION: The AEs report on this study confirmed that the results were basically consistent with the previous studies, but there were also some important safety signals that were inconsistent with or not mentioned in previous published studies. EXPERT OPINION: The opinion section discusses some of the limitations and shortcomings, proposing the areas where more effort should be invested in order to improve the safety of immunosuppressive drugs.

Designed bacteria based on natural pbr operons for detecting and detoxifying environmental lead: A mini-review.

Lead (Pb), a naturally occurring element, is redistributed in the environment mainly due to anthropogenic activities. Pb pollution is a crucial public health problem worldwide due to its adverse effects. Environmental bacteria have evolved various protective mechanisms against high levels of Pb. The pbr operon, first identified in Cupriavidus metallidurans CH34, encodes a unique Pb(II) resistance mechanism involving transport, efflux, sequestration, biomineralization, and precipitation. Similar pbr operons are gradually found in diverse bacterial strains. This review focuses on the pbr-encoded Pb(II) resistance system. It summarizes various whole-cell biosensors harboring artificially designed pbr operons for Pb(II) biomonitoring with fluorescent, luminescent, and colorimetric signal output. Optimization of genetic circuits, employment of pigment-based reporters, and screening of host cells are promising in improving the sensitivity, selectivity, and response range of whole-cell biosensors. Engineered bacteria displaying Pb(II) binding and sequestration proteins, including PbrR and its derivatives, PbrR2 and PbrD, for adsorption are involved. Although synthetic bacteria show great potential in determining and removing Pb at the nanomolar level for environmental protection and food safety, some challenges must be addressed to meet demanding application requirements.

Probiotics Improve Cognitive Impairment by Decreasing Bacteria-Related Pattern Recognition Receptor-Mediated Inflammation in the Gut-Brain Axis of Mice.

INTRODUCTION: Some studies have found that probiotics can improve cognitive impairment in Alzheimer's disease, although the specific molecular mechanism by which this occurs has not been reported. Our previous research found that probiotics inhibited bacteria-related Toll-like receptor 4- and retinoic-acid-inducible gene-I-mediated nuclear factor-κB signaling pathways to improve cognitive impairment. However, it is unclear whether probiotics have similar effects on other pattern recognition receptors that respond to bacteria. METHODS: Nine-month-old senescence-accelerated mouse prone 8 (SAMP8) mice received ProBiotic-4 (a mixture of Lactobacillus acidophilus, Bifidobacterium bifidum, Lactobacillus casei, and Bifidobacterium lactis) orally for 12 weeks. The effects on other bacteria-related pattern recognition receptors were then investigated. RESULTS: ProBiotic-4-treated SAMP8 mice showed improvement in memory deficits, synaptic and cerebral neuronal injuries, and microglial activation. ProBiotic-4 also markedly increased the expression of intestinal tight junction proteins (i.e., claudin-1, occludin, and zonula occluden-1), decreased the expression of interleukin-1ß at both the mRNA and protein levels, and reduced the expression of caspase-11, cleaved caspase-1, and α-kinase 1 (ALPK1) in the intestine and brain. CONCLUSIONS: These findings suggest that probiotics may have therapeutic potential for the treatment of inflammation in the gut-brain axis and for cognitive impairment. The mechanism of action of probiotics appears to be related to inhibition of the caspase-11/caspase-1 pathway and reduction of ALPK1 expression.

A panel of visual bacterial biosensors for the rapid detection of genotoxic and oxidative damage: A proof of concept study.

The emergence of new compounds during the past decade requires a high-throughput screening method for toxicity assay. The stress-responsive whole-cell biosensor is a powerful tool to evaluate direct or indirect damages of biological macromolecules induced by toxic chemicals. In this proof-of-concept study, nine well-characterized stress-responsive promoters were first selected to assemble a set of blue indigoidine-based biosensors. The PuspA-based, PfabA-based, and PgrpE-based biosensors were eliminated due to their high background. A dose-dependent increase of visible blue signal was observed in PrecA-, PkatG-, and PuvrA-based biosensors, responsive to potent mutagens, including mitomycin and nalidixic acid, but not to genotoxic lead and cadmium. The PrecA, PkatG, and Ppgi gene promoters were further fused to a purple deoxyviolacein synthetic enzyme cluster. Although high basal production of deoxyviolacein is unavoidable, an enhanced visible purple signal in response to mitomycin and nalidixic acid was observed as dose-dependent, especially in PkatG-based biosensors. The study shows that a set of stress-responsive biosensors employing visible pigment as a reporter is pre-validating in detecting extensive DNA damage and intense oxidative stress. Unlike widely-used fluorescent and bioluminescent biosensors, the visual pigment-based biosensor can become a novel, low-cost, mini-equipment, and high-throughput colorimetric device for the toxicity assessment of chemicals. However, combining multiple improvements can further improve the biosensing performance in future studies.

Investigation of the antibacterial effect, osteogenic activity, and tracing properties of hydroxyapatite co-doped with Tb3+ and Zn2.

Hydroxyapatite (HA) is a biomimetic biomaterial that has been widely used in bone repair for many years. However, the increased risk of infection after surgery and long-time tracing for the material distribution and degradation during bone reconstruction remain challenges in the clinic. Zinc (Zn) is considered as an indispensable microelement for humans and is characterized with antibacterial action and osteogenic activity. Terbium (Tb), a rare-earth element, emits stable fluorescence under ultraviolet light. Here, Tb3+/Zn2+ co-doped hydroxyapatite (HA:Tb/Zn) was prepared to synchronously realize the antibacterial effect, osteogenic activity, and long-time tracing property. We found that HA:Tb/Zn had a strong antibacterial effect on both Gram-positive and Gram-negative clinical infectious bacteria, as well as improved osteogenic activity. HA:Tb/Zn also displayed stable green fluorescence in vitro and in vivo, which indicated great potential for recognizing the material changes during the bone reconstruction process. The combination of the ternary functions is of great significance to control the overuse of antibiotics and realize long-time tracing, and provide a versatile design on biomaterials in bone repair.

Detection of Bioavailable Cadmium by Double-Color Fluorescence Based on a Dual-Sensing Bioreporter System.

Cadmium (Cd) is carcinogenic to humans and can accumulate in the liver, kidneys, and bones. There is widespread presence of cadmium in the environment as a consequence of anthropogenic activities. It is important to detect cadmium in the environment to prevent further exposure to humans. Previous whole-cell biosensor designs were focused on single-sensing constructs but have had difficulty in distinguishing cadmium from other metal ions such as lead (Pb) and mercury (Hg). We developed a dual-sensing bacterial bioreporter system to detect bioavailable cadmium by employing CadC and CadR as separate metal sensory elements and eGFP and mCherry as fluorescent reporters in one genetic construct. The capability of this dual-sensing biosensor was proved to simultaneously detect bioavailable cadmium and its toxic effects using two sets of sensing systems while still maintaining similar specificity and sensitivity of respective signal-sensing biosensors. The productions of double-color fluorescence were directly proportional to the exposure concentration of cadmium, thereby serving as an effective quantitative biosensor to detect bioavailable cadmium. This novel dual-sensing biosensor was then validated to respond to Cd(II) spiked in environmental water samples. This is the first report of the development of a novel dual-sensing, whole-cell biosensor for simultaneous detection of bioavailable cadmium. The application of two biosensing modules provides versatile biosensing signals and improved performance that can make a significant impact on monitoring high concentration of bioavailable Cd(II) in environmental water to reduce human exposure to the harmful effects of cadmium.

Versatile artificial mer operons in Escherichia coli towards whole cell biosensing and adsorption of mercury.

Mercury exists naturally and mainly as a man-made pollutant in the environment, where it exerts adverse effects on local ecosystems and living organisms. It is important to develop an appropriate synthetic biological device that recognizes, detects and removes the bioavailable fraction of environmental mercury. Both single-signal and double-signal output mercury biosensors were assembled using a natural mer operon as a template. Selectivity and sensitivity of whole-cell biosensors based on artificial mer operons were determined. Three whole-cell biosensors were highly stable at very high concentrations of mercuric chloride, and could detect bioavailable Hg(II) in the concentration range of 6.25-200 µM HgCl2. A novel Hg(II) bioadsorption coupled with biosensing artificial mer operon was assembled. This would allow Hg(II)-induced Hg(II) binding protein cell surface display and green fluorescence emission to be achieved simultaneously while retaining the linear relationship between fluorescent signal and Hg(II) exposure concentration. The present study provides an innovative way to simultaneously detect, quantify, and remove bioavailable heavy metal ions using an artificially reconstructed heavy metal resistance operon.

Nrf2 signalling pathway and autophagy impact on the preventive effect of green tea extract against alcohol-induced liver injury.

OBJECTIVES: To explore the potential molecular mechanism underlying the effect of green tea extract (TE), rich in tea polyphenols (TPs), on improving alcohol-induced liver injury. METHODS: Mice were intragastrically treated with 50% (v/v) alcohol administration (15 ml/kg BW) with or without three doses of TE (50, 120 and 300 mg TPs/kg BW) daily for 4 weeks, and biological changes were tested. KEY FINDINGS: The TE improved the functional and histological situations in the liver of the mice accepted alcohol administration, including enzymes for alcohol metabolism, oxidative stress and lipid accumulation. Interestingly, the TE increased the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2), with the decreasing expression of kelch-like ECH-associated protein 1 (Keap1), indicating the association between the effect of TE with Nrf2-mediated antioxidant signalling. Moreover, the TE restored the activity of autophagy, showing as lifted Beclin-1 expression, LC3B-II/LC3B-I ratio, and decreased p62 expression. Importantly, all these effects were dose-dependent. CONCLUSIONS: These findings provide a new notion for the first time that the TE preventing against alcohol-induced liver injury is closely related to accelerated metabolism of alcohol and relieved oxidative stress, which is associated with Nrf2 signalling activation and autophagy restoration, thus the reduction of lipid accumulation in liver.

Age-related cognitive decline is associated with microbiota-gut-brain axis disorders and neuroinflammation in mice.

Age-related cognitive decline is associated with chronic low grade neuroinflammation that may result from a complex interplay among many factors, such as bidirectional communication between the central nervous system (CNS) and gut microbiota. The present study used 2-month-old (young group) and 15-month-old (aged group) male C57BL/6 mice to explore the potential association between age-related cognitive decline and the microbiota-gut-brain axis disorder. We observed that aged mice exhibited significant deficits in learning and memory, neuronal and synaptic function compared with young mice. Aged mice also exhibited significant dysbiosis of the gut microbiota. Disruptions of the intestinal barrier and blood-brain barrier were also observed, including increases in intestinal, low-grade systemic and cerebral inflammation. Furthermore, plasma and brain levels of lipopolysaccharide (LPS) were significantly higher in aged mice compared with young mice, with increasing expression of Toll-like receptor 4 (TLR4) and myeloid differential protein-88 (MyD88) and the nuclear translocation of nuclear factor κB (NF-κB) in intestinal and brain tissues. These findings showed that microbiota-gut-brain axis dysfunction that occurs through LPS-induced activation of the TLR4/NF-κB signaling pathway is implicated in age-related neuroinflammation and cognitive decline.

Effect of Prescription Tongxin on Endothelial Progenitor Cells in Peripheral Blood.

CONTEXT: Coronary heart disease (CHD) refers to a disease where coronary atherosclerosis induces stenosis or obstruction of the blood vessels. Endothelial progenitor cells (EPCs) function to protect and repair the vascular endothelium, and their functional activity state reflects the ability of the body to repair vascular damage. In the peripheral blood of patients with CHD, the density of EPCs decreases, and the function of EPCs is low. OBJECTIVE: This study aimed to investigate the effects of a China Food and Drug Administration (CFDA)-approved prescription medicine, Tongxin, on the density and function of endothelial progenitor cells (EPCs) in peripheral blood. DESIGN: In this study, a randomized, single blind, parallel controlled clinical trial was used. The single blind subjects were subjects. SETTING: The study took place in the Cardiology and Emergency Departments at Shanghai Municipal Hospital of Traditional Chinese Medicine in Shanghai, China. PARTICIPANTS: Participants were 48 patients with coronary heart disease at the hospital. INTERVENTION: Participants were randomly divided into 2 groups (n = 24 each): a control group and an intervention group. Both groups received routine drug treatments, such as platelet inhibitors, nitrates, ß-receptor blockers, statins, angiotensin-converting-enzyme (ACE) inhibitors, angiotensin II receptor antagonists (ARBs), and calcium blockers. The control group was treated with the Shexiang Baoxin Pill, while the intervention group was treated with prescription Tongxin. The course of treatment was 3 months for both groups. OUTCOME MEASURES: Changes in the density and function of EPCs in the peripheral blood of the 2 groups were measured at baseline and postintervention, and the clinical efficacy of the 2 treatments was statistically analyzed. RESULTS: The density of EPCs was significantly higher in both groups after 3 months of treatment, compared to the densities at baseline (P < .05). The change in density between baseline and postintervention was significantly greater for the intervention group than for the control group (P < .05). For the control group, the proliferative vitality [optical density (OD)] value of the EPCs was significantly higher than that at baseline from the fourth day of treatment (P < .05). In the intervention group, the OD value was significantly higher than that at baseline from the first day of treatment (P < .05). Furthermore, the intervention group's cells began to enter the logarithmic growth phase of increase from the fifth day of treatment, and the group's increase as significantly higher than the control group's from the fifth to the seventh dayof treatment (P < .05 for all 3 days). Moreover, the total effective rate was higher in the intervention group than in the control group (P < .05). CONCLUSIONS: Prescription Tongxin can stimulate the release of EPCs from the bone marrow to the peripheral blood of patients with CHD, can significantly increase the proliferation of EPCs in the peripheral blood, and can improve the clinical symptoms of patients. Its curative effect was greater than that of the control treatment.

Chronic periodontitis induces microbiota-gut-brain axis disorders and cognitive impairment in mice.

Epidemiological studies suggest that chronic periodontitis (CP) is closely associated with the incidence and progression of cognitive impairment. The present study investigated the causal relationship between CP and cognitive decline and the underlying mechanism in mice. Long-term ligature around the left second maxillary molar tooth was used to induce CP in mice. Severe alveolar bone loss and inflammatory changes were observed in gingival tissues, accompanied by progressive cognitive deficits during a 12-month period. We also observed cerebral neuronal and synaptic injury and glial activation in this mouse model of CP. Furthermore, CP mice exhibited significant dysbiosis of the oral and gut microbiota, disruption of the intestinal barrier and blood-brain barrier, increases in the serum contents of proinflammatory cytokines and lipopolysaccharide (LPS), and increases in brain LPS levels, Toll-like receptor 4 (TLR4) expression, nuclear factor-κB (NF-κB) nuclear translocation and proinflammatory cytokine mRNA levels. These results indicate that CP may directly induce progressive cognitive decline and its mechanism is probably related to microbiota-gut-brain axis disorders, LPS/TLR4/NF-κB signaling activation and neuroinflammatory responses in mice. Therefore, the microbiota-gut-brain axis may provide the potential strategy for the prevention and treatment of CP-associated cognitive impairment.

Genetic control of violacein biosynthesis to enable a pigment-based whole-cell lead biosensor.

Environmental risks continue to grow due to heavy metal contamination caused by anthropogenic activities. Accumulation of harmful quantities of lead poses a threat to aquatic organisms, plants, and human beings. Whole-cell biosensors, which can proliferate independently, can detect the bioavailable fraction to assess the effect of target heavy metal on the environmental ecosystem. In this study, the biosynthesis pathway of violacein was heterogeneously constructed under the control of the T7 lac promoter in E. coli. A dose-response relationship existed between the inducer and the production of violacein. The biosynthesis pathway of violacein was finally engineered under the regulation of Pb(ii)-dependent metalloregulator PbrR to assemble Pb(ii)-inducible whole-cell biosensor. It permitted specific biosensing of Pb(ii) with extraordinary selectivity, and could resist the interferences from various metal ions. Color change by the intracellular accumulation of violacein could be recognized with the naked eye directly with high concentration of lead exposure, and quantified by determining the absorbance at 490 nm after butanol extraction. A good linear range for Pb(ii) concentrations of 0.1875-1.5 µM was obtained. The novel pigment-based whole-cell biosensor could detect concentrations as low as 0.1875 µM Pb(ii) based on in vitro quantification of violacein extracted by butanol, which is significantly lower than reported fluorescent protein-based PbrR-regulated biosensors based on direct measurement of whole cell fluorescence. These results indicate that genetically controlled violacein biosynthesis can enable a sensitive, visual, and qualitative biosensor for monitoring the presence of bioavailable Pb(ii) in lead-contaminated water.

Tibetan medicine Ru-yi-Zhen-bao Pills exhibits anti-migraine effect through mediating PAG anti-nociceptive channel.

ETHNOPHARMACOLOGICAL RELEVANCE: Migraine is a disabling neurovascular disorder, which increases risk of cardiovascular events and is a social burden worldwide. The present first-line anti-migraine medications can cause overwhelming side-effects, of which one includes the onset of cardiovascular disease. As one of the marketed Tibetan drugs, Ru-yi-Zhen-bao Pills (RYZBP) have been clinically used to treat cardiovascular disorders and as anti-migraine medication. However, there is currently no research exploring the anti-migraine actions of RYZBP. AIM OF THE STUDY: The current research was designed to assess the anti-migraine roles of RYZBP and explore the underlying mechanisms in a nitroglycerin (NTG)-induced migraine rat model trial. MATERIALS AND METHODS: 120 rats were randomly divided into the following six groups of 20 rats each: normal control group, model control group, positive control group, and RYZBP high/medium/low-dose groups (Ru-yi-Zhen-bao Pills; TH 1.00 g/kg, TM 0.50 g/kg and TL 0.25 g/kg). All rats were administered intragastrically for 7 consecutive days, which were subcutaneously injected with the NTG (10 mg/kg) after the last gavage (except in the normal control group). 3min after NTG treatment, 30 rats (5 rats from each group) were anesthetized and devoted to electroencephalogram(EEG) testing, which was used to evaluate the analgesic effect of RYZBP. One hour after NTG treatment, the rest of the 90 rats (15 rats from each group) were anesthetized and midbrain tissue sample was dissected. The dissection was then washed with physiological saline and collected. The histopathological changes in the periaqueductal gray(PAG) of 5 tissue samples were determined by aematoxylin-eosin (H&E) staining, as well as an estimation of substance P (SP) and neurokinin 1 receptor (NK1R) expression through immunohistochemically staining(IHC). Another 5 midbrain preparations were carried out to evaluate calcitonin gene-related peptide (CGRP), proenkephalin (PENK), SP, and cholecystokinin (CCK) expressions by real-time quantitative polymerase chain reaction (RT-qPCR). The rest of the 5 brainstem tissues were then used to measure CCK, CGRP, and opioid peptide receptor (DORR) levels by western blotting(WB). RESULTS: In the EEG test, RYZBP (TM 0.50 g / kg) treatment transformed the EEG pain-wave of the NTG-induced migraine model rats in different time period. In the mechanism assay, compared with the model control group, RYZBP pretreatment reduced inflammatory cell infiltration, fibrosis and vacuolation of neuronal cells of PAG tissue seen by HE staining. IHC experiments further showed that RYZBPTM up-regulated SP expression levels and enhanced NK1R levels in the NTG-induced migraine rats (P < 0.05). Therapeutic administration of RYZBP also increased PENK mRNA expression and DORR protein level. Both RT-qPCR and western blotting trials indicated that RYZBP treatment significantly decreased CCK and CGRP expression levels (P < 0.01 or P < 0.05) in the NTG-induced migraine rats. CONCLUSIONS: RYZBP has the potential to be an effective anti-migraine treatment through suppressing the EEG pain-wave, increasing the levels of SP, PENK, DORR and reducing expression of CCK and CGRP. Mediating the PAG anti-nociceptive channel and inhibiting central sensitization were the two potential mechanisms, which offers further evidence for clinical therapy.

[Effects of Different Stimulators on Proliferation of Peripheral Blood Lymphocyte Subsets].

OBJECTIVE: To investigate the effects of different stimultors (PHA, PMA and IL-2) and culture systems (PBMC and whole blood) on the proliferation of human peripheral blood lymphocyte subsets, so as to provide the experimental basis for selecting the appropriate system according to the experimental purposes. METHODS: A total of 10 ml serum samples were collected from healthy volunteers (n=6). The 300 µl whole blood was directly used to detect lymphocyte subsets by flow cytometry. The 400 µl whole blood were inoculated respectively with 3 different stimulators at 37℃ and 5% CO2 for 60 h; Three different stimulators were also added to the PBMC which were isolated from 2 ml whole blood. Then the proliferation ability of lymphocyte subsets was analyzed by flow cytometry. RESULTS: After the PBMC were stimulated with PHA, CD4-CD8-CD3+ lymphocytes were the most subset; The proportion of CD3+CD4+ T lymphocytes and CD3-CD19+ B lymphocytes decreased after being stimulated by PMA (P<0.01, P<0.05); the lymphocyte subset ratio had no significant change after being stimulated by IL-2. After the whole blood system was stimulated with PHA, the CD4+/CD8+ T lymphoblasts were main subsets, the counts of B lymphocytes and NK cells were reduced; after being stimulated with PMA, the number of CD8+CD3+ T lymphoblast and CD4-CD8-T lymphocytes increased, the B/NK cells were not distinguished with the surface markers; after the whole blood system was stimulated with IL-2, the proportion of NK cells significantly increased (P<0.05). CONCLUSION: Lymphocyte proliferation stimulated by PMA is the fastest, while the effect of IL-2 on the lymphocyte subset proportion stimulated by IL-2 is the minimal. After being stimulated by PHA the division cycles of lymphocyte are the most.

[Effects of trampling disturbance on soil organic carbon fractions and mineralization potential of biological soil crusts in the Loess Plateau Region, China]. / 黄土丘陵区踩踏干扰对生物土壤结皮有机碳组分及碳矿化潜力的影响.

The experiment was conducted in the plots that had been enclosed for nearly 20 years in the hilly Loess Plateau region. The effects of trampling disturbance on the biological soil crust (biocrust) coverage, soil organic carbon (SOC), soil easily oxidizable carbon (SEOC), SOC mineralization amount and mineralization rate were investigated. The biocrust SOC mineralization potential after disturbance in different soil layers were simulated by a first-order kinetic equation. The results showed that the coverage of cyanobacteria biocrust and moss biocrust significantly decreased with the increases of disturbance intensity. Compared to no disturbance, the cyanobacteria coverage declined by 264%-339% and moss coverage declined by 46%-127%. Compared to no disturbance, SOC content in biocrust layer significantly decreased by 211%-300%. No significant difference was found among the five disturbance intensities. Disturbance increased SEOC content in biocrust layer, and the variation amounted to 1.5-3.4 g·kg-1, with 30%, 40% and 50% distur-bance differed significantly to no disturbance. Disturbance significantly increased biocrust SOC mineralization cumulative amount. However, SOC mineralization rate did not show any significant change. The SOC mineralization cumulative amount under 40% disturbance intensity increased by 77% compared to that under no disturbance. Disturbance significantly increased SOC mineralization potential in biocrust layer, but with no influence in 0-2 cm and 2-5 cm soil layers. The 40% disturbance intensity significantly increased SOC mineralization potential by 4.7 g·kg-1. The results of principal component analysis showed that SOC, SEOC, SMC and mineralization rate explained 76.7% of the variation of SOC mineralization potential in biocrust layer. Disturbance might be a main factor driving the increases of biocrust SOC mineralization potential in this area.

Surface display of metal binding domain derived from PbrR on Escherichia coli specifically increases lead(II) adsorption.

OBJECTIVES: To improve the Pb2+ biosorption capacity of the potential E. coli biosorbent, a putative Pb2+ binding domain (PbBD) derived from PbrR was efficiently displayed on to the E. coli cell surface. RESULTS: The PbBD was obtained by truncating the N-terminal DNA-binding domain and C-terminal redundant amino acid residues of the Pb2+-sensing transcriptional factor PbrR. Whole-cell sorbents were constructed with the full-length PbrR and PbBD of PbrR genetically engineered onto the surface of E. coli cells using Lpp-OmpA as the anchor. Followed by a 1.71-fold higher display of PbBD than PbrR, the presence of PbBD on the surface of E. coli cells enabled a 1.92-fold higher Pb2+ biosorption than that found in PbrR-displayed cells. Specific Pb2+ binding via PbBD was the same as Pb2+ binding via the full-length PbrR, with no observable decline even in the presence of Zn2+ and Cd2+. CONCLUSIONS: Since surface-engineered E. coli cells with PbBD increased the Pb2+ binding capacity and did not affect the adsorption selectivity, this suggests that surface display of the metal binding domain derived from MerR-like proteins may be used for the bioremediation of specific toxic heavy metals.

Prospective Study of Stereotactic Body Radiation Therapy for Thymoma and Thymic Carcinoma: Therapeutic Effect and Toxicity Assessment.

Stereotactic body radiation therapy (SBRT) is an important modality in treatment of tumors. We hypothesized that SBRT can achieve excellent local control with limited toxicity in patients with thymic tumors. A single-institution prospective study was performed with 32 patients who underwent SBRT of thymoma and thymic carcinoma between 2005 and 2014. Thirty-two patients including 39 target lesions were analyses in this study. Almost half of the patients (46.9%) were type C by histopathology and more than half (56.3%) were classified into stage IVA or IVB. The median dose of SBRT for gross tumor volume (GTV) was 56 Gy (range 49-70 Gy). Results showed that the response rate was 96.9% after SBRT and the median tumor shrinkage rate was 62.2% (range 3.8-100%). For the patients with both stage II-III and type A-B (n = 6), the median PFS was 28 months. In-field failure was only observed in 4 patients, and outside-field failure was seen in 2 patients. The local control rate was 81.25%. Patients treated with SBRT had an excellent local control with mild toxicities, which suggests that SBRT is feasible for the patients with thymic tumors who are unable to undergo either surgery or conventionally fractionated radiation therapy.

Isolation and characterization of antimicrobial peptides from healthy male urine.

A complex of low-molecular cationic peptides, extracted from human urine by a combination membrane ultrafiltration and weak cation exchange chromatography, was characterized in this study. It provides a simpler solution for the development of novel antimicrobial peptides from biological liquid waste.

Comparative genomic analysis identifies structural features of CRISPR-Cas systems in Riemerella anatipestifer.

BACKGROUND: Riemerella anatipestifer infection is a contagious disease that has resulted in major economic losses in the duck industry worldwide. This study attempted to characterize CRISPR-Cas systems in the disease-causing agent, Riemerella anatipestifer (R. anatipestifer). The CRISPR-Cas system provides adaptive immunity against foreign genetic elements in prokaryotes and CRISPR-cas loci extensively exist in the genomes of archaea and bacteria. However, the structure characteristics of R. anatipestifer CRISPR-Cas systems remains to be elucidated due to the limited availability of genomic data. RESULTS: To identify the structure and components associated with CRISPR-Cas systems in R. anatipestifer, we performed comparative genomic analysis of CRISPR-Cas systems in 25 R. anatipestifer strains using high-throughput sequencing. The results showed that most of the R. anatipestifer strains (20/25) that were analyzed have two CRISPR loci (CRISPR1 and CRISPR2). CRISPR1 was shown to be flanked on one side by cas genes, while CRISPR2 was designated as an orphan. The other analyzed strains harbored only one locus, either CRISPR1 or CRISPR2. The length and content of consensus direct repeat sequences, as well as the length of spacer sequences associated with the two loci, differed from each other. Only three cas genes (cas1, cas2 and cas9) were located upstream of CRISPR1. CRISPR1 was also shown to be flanked by a 107 bp-long putative leader sequence and a 16 nt-long anti-repeat sequence. Combined with analysis of spacer organization similarity and phylogenetic tree of the R. anatipestifer strains, CRISPR arrays can be divided into different subgroups. The diversity of spacer organization was observed in the same subgroup. In general, spacer organization in CRISPR1 was more divergent than that in CRISPR2. Additionally, only 8 % of spacers (13/153) were homologous with phage or plasmid sequences. The cas operon flanking CRISPR1 was observed to be relatively conserved based on multiple sequence alignments of Cas amino acid sequences. The phylogenetic analysis associated with Cas9 showed Cas9 sequence from R. anatipestifer was closely related to that of Bacteroides fragilis and formed part of the subtype II-C subcluster. CONCLUSIONS: Our data revealed for the first time the structural features of R. anatipestifer CRISPR-Cas systems. The illumination of structural features of CRISPR-Cas system may assist in studying the specific mechanism associated with CRISPR-mediated adaptive immunity and other biological functions in R. anatipestifer.

[Functional Analysis of DNA Damage Repair Factor WDR70 and Its Mutation in Ovarian Cancer].

OBJECTIVES: To analyze the cellular function of the newly discovered DNA damage repair factor WDR70, and investigate the mutation in ovarian cancer to verify if function loss of the WDR70gene was associated with ovarian cancer. METHODS: The WDR70 gene was silenced by using siRNA technique or overexpressed its wild and mutation type by with lentivirus and plasmid in hunman cells. The subcellular localization and biochemical function of WDR70 was analyzes by indirect immunofluorescence and immunoblotting. The expression level of WDR70 and the mutations of its cDNA was checked with RT-PCR sequencing for 1 normal ovarian tissue and 16 ovarian cancer specimen. RESULTS: We found gene silencing of WDR70 or overexpression of WDR70 mutation type disrupts the phosphorylation level of homologous recombination functional protein RPA32 and the ability of recruitment at DNA damage site of recombinase RAD51, the loss of function of WDR70 also causes the elevation of the chromosome breakage in metaphase. Meanwhile, we also noticed that the existence of multiple mutations in genomic WDR70 in ovarian cancer specimen. CONCLUSIONS: Our results defined that in vitro system, WDR70 is a DNA damage repair gene, silencing of WDR70 or overexpression of WDR70 mutation type disrupts homologous recombination and chromosomal instability; the frequent mutations of WDR70 gene in genome of ovarian cancer specimens could also lead to DNA repair defeat and gene instability. Consequently WDR70 gene could represent an anti-cancer mechanism for ovarian cancer.