Treadmill exercise can regulate the redox balance in the livers of APP/PS1 mice and reduce LPS accumulation in their brains through the gut-liver-kupffer cell axis

A growing body of clinical data has shown that patients with Alzheimer's disease (AD) have symptoms such as liver dysfunction and microbial-gut-brain axis dysfunction in addition to brain pathology, presenting a systemic multisystemic pathogenesis. Considering the systemic benefits of exercise, here, we first observed the effects of long-term treadmill exercise on liver injuries in APP/PS1 transgenic AD mice and explored the potential mechanisms of the gut-liver-brain axis's role in mediating exercise's ability to reduce bacterial lipopolysaccharide (LPS) pathology in the brain. The results showed that the livers of the AD mice were in states of oxidative stress, while the mice after long-term treadmill exercise showed alleviation of their oxidative stress, their intestinal barriers were protected, and the ability of their Kupffer cells to hydrolyze LPS was improved, in addition to the accumulation of LPS in their brains being reduced. Notably, the livers of the AD mice were in immunosuppressed states, with lower pro-oxidative and antioxidative levels than the livers of the wild-type mice, while exercise increased both their oxidative and antioxidative levels. These results suggest that long-term exercise modulates hepatic redox homeostasis in AD mice, attenuates oxidative damage, and reduces the accumulation of LPS in the brain through the combined action of the intestine-liver-Kupffer cells.

[Prognostic value of the Second Revision of the International Staging System in patients with newly diagnosed transplant-eligible multiple myeloma]

Objective: To verify the predictive value of the Second Revision of the International Staging System (R2-ISS) in newly diagnosed patients with multiple myeloma (MM) who underwent first-line autologous hematopoietic stem cell transplantation (ASCT) in a new drug era in China. Methods: This multicenter retrospective cohort study enrolled patients with newly diagnosed MM from three centers in China (Beijing Chao-Yang Hospital, Capital Medical University; the First Affiliated Hospital, Sun Yat-Sen University, and the Second Affiliated Hospital of Naval Medical University) from June 2008 to June 2018. A total of 401 newly diagnosed patients with MM who were candidates for ASCT were enrolled in this cohort, all received proteasome inhibitor and/or immunomodulator-based induction chemotherapy followed by ASCT. Baseline and follow-up data were collected. The patients were regrouped using R2-ISS. Progression-free survival (PFS) and overall survival (OS) were analyzed. The Kaplan-Meier method was used to analyze the survival curve and two survival curves were compared using the log-rank test. Cox regression analysis were performed to analyze the relationship between risk factors and survival. Results: The median age of the patients was 53 years (range 25-69 years) and 59.5% (240 cases) were men. Newly diagnosed patients with renal impairment accounted for 11.5% (46 cases). According to Revised-International Staging System (R-ISS), 74 patients (18.5 %) were diagnosed with stage Ⅰ, 259 patients (64.6%) with stage Ⅱ, and 68 patients (17.0%) with stage Ⅲ. According to the R2-ISS, the distribution of patients in each group was as follows: 50 patients (12.5%) in stage Ⅰ, 95 patients (23.7%) in stage Ⅱ, 206 patients (51.4%) in stage Ⅲ, and 50 patients (12.5%) in stage Ⅳ. The median follow-up time was 35.9 months (range, 6-119 months). According to the R2-ISS stage, the median PFS in each group was: 75.3 months for stage Ⅰ; 62.0 months for stage Ⅱ, 39.2 months for stage Ⅲ, and 30.3 months for stage Ⅳ; and the median OS was not reached, 86.6 months, 71.6 months, and 38.5 months, respectively. There were statistically significant differences in PFS and OS between different groups (both P<0.001). Multivariate Cox regression analysis showed that stages Ⅲ and Ⅳ of the R2-ISS were independent prognostic factors for PFS (HR=2.37, 95%CI 1.30-4.30; HR=4.50, 95%CI 2.35-9.01) and OS (HR=4.20, 95%CI 1.50-11.80; HR=9.53, 95%CI 3.21-28.29). Conclusions: The R2-ISS has significant predictive value for PFS and OS for transplant-eligible patients with MM in the new drug era. However, the universality of the R2-ISS still needs to be further verified in different populations.

Reexamining the Causes and Effects of Cholesterol Deposition in the Brains of Patients with Alzheimer's Disease

Alzheimer's disease (AD) is a degenerative disease of the central nervous system. Numerous studies have shown that imbalances in cholesterol homeostasis in the brains of AD patients precede the onset of clinical symptoms. In addition, cholesterol deposition has been observed in the brains of AD patients even though peripheral cholesterol does not enter the brain through the blood‒brain barrier (BBB). Studies have demonstrated that cholesterol metabolism in the brain is associated with many pathological conditions, such as amyloid beta (Aβ) production, Tau protein phosphorylation, oxidative stress, and inflammation. In 2022, some scholars put forward a new hypothesis of AD: the disease involves lipid invasion and its exacerbation of the abnormal metabolism of cholesterol in the brain. In this review, by discussing the latest research progress, the causes and effects of cholesterol retention in the brains of AD patients are analyzed and discussed. Additionally, the possible mechanism through which AD may be improved by targeting cholesterol is described. Finally, we propose that improving the impairments in cholesterol removal observed in the brains of AD patients, instead of further reducing the already impaired cholesterol synthesis in the brain, may be the key to preventing cholesterol deposition and improving the corresponding pathological symptoms.

Safety and efficacy of intravitreal injection of conbercept for the treatment of patients with choroidal neovascularization secondary to pathological myopia: Results from the SHINY study

PURPOSE

To evaluate the safety and efficacy of intravitreal injections of 0.5 mg conbercept in patients with choroidal neovascularization secondary to pathological myopia (pmCNV).

METHODS

The 177 pmCNV patients were randomly assigned in a 3:1 ratio to receive conbercept or sham injection, respectively. The conbercept group receive conbercept intravitreal injections administered on a pro re nata (PRN) basis after 3 monthly loading doses. The sham group received three consecutive monthly sham injections and then one conbercept injection followed by PRN conbercept intravitreal injections.

RESULTS

At month 3, the mean BCVA for the two groups were improved by 12.0 letters (conbercept group, from 54.05 letters to 66.05 letters) and 0.6 letters (sham group, from 49.77 letters to 50.33 letters), respectively (p < 0.001). The mean central retinal thickness (CRT) at month 3 in the two groups decreased 62.0 μm (conbercept group, from 348.90 μm to 286.18 μm) and 4.4 μm (sham group, from 347.86 μm to 343.47 μm) (p < 0.001). At month 9, the mean BCVA improved by 13.3 letters in the conbercept group and 11.3 letters in the sham group. The mean CRT decreased 73.6 μm in the conbercept group and 55.9 μm in the sham group (p < 0.001). The most common ocular adverse events were associated with intravitreal injections, such as conjunctival haemorrhage and increased intraocular pressure.

CONCLUSION

Intravitreal injections of 0.5 mg conbercept provided improvement in visual and anatomical outcomes in pmCNV patients with low rates of ocular and nonocular safety events.

Aerobic exercise regulates GPR81 signal pathway and mediates complement- microglia axis homeostasis on synaptic protection in the early stage of Alzheimer's disease

AIMS

Memory impairment is a major clinical manifestation in Alzheimer's disease (AD) patients, while regular exercise may prevent and delay degenerative changes in memory functions, and our aim is to explore the influence and molecular mechanisms of aerobic exercise on the early stages of Alzheimer's disease.

MAIN METHODS

3-month-old male APP/PS1 transgenic AD mice and C57BL/6J wild-type mice were randomly divided into four groups: wild-type and APP/PS1 mice with sedentary (WT-SED, AD-SED), and running (WT-RUN, AD-RUN) for 12-weeks. The spatial learning and memory function, RNA-sequencing, spine density, synaptic associated protein, mRNA and protein expression involved in G protein-coupled receptor 81 (GPR81) signaling pathway, and complement factors in brain were measured.

KEY FINDINGS

Aerobic exercise improved spatial learning and memory in APP/PS1 mice, potentially attributed to increased dendritic spine density. Subsequently, potential underlying mechanisms were identified through RNA sequencing: regular aerobic exercise could activate the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) cAMP/PKA signaling pathway and upregulate synaptic function-related proteins to promote synaptic growth, possibly by modulating GPR81. Notably, regular aerobic exercise inhibited microglial activation, reversed the microglial phenotype, reduced the production of initiation factor C1q and central factor C3 in the complement cascade in the brain, prevented the colocalization of microglia and PSD-95, and thus prevented synaptic loss.

SIGNIFICANCE

Physical exercise could play a critical role in improving cognitive function in AD by promoting synaptic growth and preventing synaptic loss, which may be related to the regulation of the GPR81/cAMP/PKA signaling pathway and inhibition of complement-mediated microglial phagocytosis of synapses.

[Research advances on the application of free flaps in repairing diabetic foot ulcers]

Free flaps have been successfully used in the repair of diabetic foot ulcers (DFUs), which can reduce amputation rate, maintain normal gait of patients, and improve life quality of patients. However, there are still many challenges in the repair of DFUs with free flaps, and many problems need to be solved. This paper summarizes the selection of patients, preoperative cautions, types of flaps, methods of vascular anastomosis, clinical effects, and existing problems in using free skin flaps for repairing DFUs.

[Discussion on surgical treatment mode of diabetic foot wounds]

Diabetic foot wounds have a high incidence and uneven therapeutic effect, so it is necessary to explore the suitable treatment mode of diabetic foot wounds. The existing surgical treatment modes for diabetic foot wounds include the multi-disciplinary team (MDT) cooperation mode and the "five-in-one comprehensive limb salvage" treatment mode. These two modes have their own advantages, but are inconvenient to some extent. In response to this problem, the author's team proposed the wound surgical integrated treatment (WSIT) mode based on years of experience in repairing diabetic foot wounds, emphasizing the perioperative management by MDT, and the local wound management by WSIT team, which significantly improved the diagnosis and treatment efficiency of patients with diabetic foot wounds.

Treadmill Exercise Modulates Intestinal Microbes and Suppresses LPS Displacement to Alleviate Neuroinflammation in the Brains of APP/PS1 Mice

Neuroinflammation occurs throughout the pathogenesis of Alzheimer’s disease (AD). Here, we investigated the effects of treadmill exercise on neuroinflammation in APP/PS1 transgenic AD mice and the potential involvement of microbe–gut–brain axis (MGB) mechanisms based on growing evidence that AD’s pathogenesis is correlated with a deterioration in the function of gut microbiota. APP/PS1 transgenic AD mice were subjected to 12 weeks of treadmill exercise, followed by spatial memory tests. After the behavioral study, the amyloid (Aβ) pathology, gut microbes and metabolites, bacterial lipopolysaccharide (LPS) displacement, and degree of neuroinflammation were analyzed. We found that this strategy of exercise enriched gut microbial diversity and alleviated neuroinflammation in the brain. Notably, exercise led to reductions in pathogenic bacteria such as intestinal Allobaculum, increases in probiotic bacteria such as Akkermansia, increased levels of intestine–brain barrier proteins, and attenuated LPS displacement. These results suggest that prolonged exercise can effectively modulate gut microbes and the intestinal barrier and thereby reduce LPS displacement and ultimately alleviate AD-related neuroinflammation.

Aerobic Exercise Alleviates Abnormal Autophagy in Brain Cells of APP/PS1 Mice by Upregulating AdipoR1 Levels

Abnormalities in autophagy are associated with Alzheimer’s disease (AD)-like lesions. Studies have shown that exercise can significantly improve AD autophagy abnormalities, but the mechanism underlying this phenomenon remains unclear. APN not only has an important regulatory effect on AD autophagy abnormalities, but also is affected by exercise. Therefore, this study aims to reveal the pathway by which exercise regulates abnormal autophagy in AD using the APN–AdipoR1 signaling pathway as an entry point. The results of the study showed that APP/PS1 double transgenic AD model mice (24 weeks) showed decreased AdipoR1 levels in the brain, abnormal autophagy, increased Aβ deposition, and increased cell apoptosis, and dendritic spines and cognitive function were reduced. Twelve weeks of aerobic exercise enhanced lysosomes and alleviated abnormal autophagy by activating the AdipoR1/AMPK/TFEB signaling pathway in the brains of AD mice, thereby alleviating Aβ deposition and its associated AD-like abnormalities. These findings suggest that the AdipoR1 plays an important role in aerobic exercise’s alleviation of abnormal autophagy in AD brain cells and alleviation of AD-like lesions.

Identification of a Vitamin-D Receptor Antagonist, MeTC7, which Inhibits the Growth of Xenograft and Transgenic Tumors In Vivo

Vitamin-D receptor (VDR) mRNA is overexpressed in neuroblastoma and carcinomas of lung, pancreas, and ovaries and predicts poor prognoses. VDR antagonists may be able to inhibit tumors that overexpress VDR. However, the current antagonists are arduous to synthesize and are only partial antagonists, limiting their use. Here, we show that the VDR antagonist MeTC7 (5), which can be synthesized from 7-dehydrocholesterol (6) in two steps, inhibits VDR selectively, suppresses the viability of cancer cell-lines, and reduces the growth of the spontaneous transgenic TH-MYCN neuroblastoma and xenografts in vivo. The VDR selectivity of 5 against RXRα and PPAR-γ was confirmed, and docking studies using VDR-LBD indicated that 5 induces major changes in the binding motifs, which potentially result in VDR antagonistic effects. These data highlight the therapeutic benefits of targeting VDR for the treatment of malignancies and demonstrate the creation of selective VDR antagonists that are easy to synthesize.

[The prognostic relationship between CD56 expression and newly diagnosed multiple myeloma]

Objective: To evaluate the prognostic value of CD56 expression in newly diagnosed MM (NDMM). Methods: A total of 332 NDMM patients were enrolled in Beijing Chaoyang Hospital, Capital Medical University from January 1, 2011 to January 1, 2021, with a median age of 60 years and a male to female ratio of 1.2∶1. CD56 expression on myeloma cells was detected by flow cytometry before induction therapy. Overall survival (OS) and progression-free survival (PFS) data were collected. In order to reduce the confounding factors, the propensity score matching technique was used to match CD56 positive versus negative patients at a ratio of 1∶1. Results: Among 332 patients, CD56 positivity rate was 65.1% (216/332). Patients with CD56 expression had significantly longer median OS (58.4 vs. 43.1 months, P=0.024) and PFS (28.7 vs. 24.1 months, P=0.013) than those with negative CD56. Univariate Cox proportional hazards regression analyses showed that CD56 expression was positively correlated with OS (HR=0.644, 95%CI 0.438-0.947, P=0.025) and a favorable prognostic factor for PFS (HR=0.646, 95%CI 0.457-0.913,P=0.013). The favorable effect of CD56 expression on PFS was confirmed in multivariate analysis (HR=0.705, 95%CI 0.497-0.998, P=0.049), but OS was not affected (P>0.05).In the propensity score matching analysis, 194 patients with 97 in each group were identified. CD56 positivity consistently predicted longer PFS (34.2 vs.25.1 months, P=0.047), but not OS (63.4 vs.43.1 months, P=0.056). Conclusion: These results demonstrate that CD56 expression is a favorable prognostic factor for PFS of newly diagnosed MM patients.

[Autologous stem cell transplantation improve the survival of newly diagnosed multiple myeloma patients]

目的

评估自体造血干细胞移植（auto-HSCT）对初治多发性骨髓瘤（MM）疗效及生存的影响。

方法

回顾性分析2008年10月1日至2019年10月1日243例65岁以下接受auto-HSCT的初治MM患者，同时以同期176例≤65岁适合移植但未进行auto-HSCT的初治MM患者作为对照，评估auto-HSCT对患者疗效及生存的影响。为平衡auto-HSCT和非auto-HSCT患者之间各因素的分布，利用倾向性评分匹配技术按照1∶1比例匹配以减少组间的偏差。

结果

通过倾向性评分匹配分析，共筛选出128例患者（每组64例）。64例患者诱导治疗后接受auto-HSCT，24例（37.5％）获得严格意义的完全缓解（sCR），16例（25.0％）获得完全缓解（CR），15例（23.4％）获得非常好的部分缓解（VGPR），9例（14.1％）获得部分缓解（PR），auto-HSCT组疗效明显优于非auto-HSCT组（P＝0.032）。与非auto-HSCT组相比，auto-HSCT组总生存（OS）和无进展生存（PFS）期明显延长［OS：87.6（95％ CI 57.3～117.9）个月对53.9（95％ CI 36.1～71.7）个月，P＝0.011；PFS：42.2（95％ CI 29.9～54.5）个月对22.4（95％ CI 17.1～27.7）个月，P＝0.007］。多因素分析显示auto-HSCT是OS（HR＝0.448，95％CI 0.260～0.771，P＝0.004）和PFS（HR＝0.446，95％CI 0.280～0.778，P＝0.003）的独立保护因素。

结论

auto-HSCT可改善适合移植初治MM患者的OS和PFS。

Hypomethylation of CTCFL promoters as a noninvasive biomarker in plasma from patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third deadliest cancer in the world with high morbidity and poor prognosis. CTCFL (CCCTC-binding factor like) is a member of the cancer testis antigen (CTA) family with oncogenic properties. To demonstrate whether the hypomethylation of CTCFL promoters in plasma could be used as a noninvasive biomarker to predict poor prognosis of HCC, we extracted cell-free DNA from the plasma and detected the methylation status of CTCFL in 43 HCC, 5 liver cirrhosis and 6 benign lesion samples using methylation specific PCR (MSP). Our study indicated that the hypomethylation of CTCFL promoters in HCC plasma samples (60.4%) was significantly different from that in benign lesion plasma samples (16.7%) with a p-value of 0.043. Analysis of clinicopathological data showed that the methylation status of CTCFL promoters was significantly correlated with microvascular involvement (MVI) (p=0.001) and postoperative recurrence (p=0.031). Furthermore, clinical prognosis data of 347 HCC patients from The Cancer Genome Atlas (TCGA) database displayed that the hypomethylated group had worse overall survival than the hypermethylated group (p=0.0056). In conclusion, we provide evidence that the hypomethylation of CTCFL promoters in cell-free DNA is a biomarker for monitoring HCC patients, which can be used as a noninvasive prediction index for tumor recurrence and provide the individualized decision-making for clinicians.

MicroRNA-30b regulates the polarity of retinal ganglion cells by inhibiting semaphorin-3A

Purpose

Retinal ganglion cell (RGC) polarity plays an important role in optic nerve regeneration. This study was designed to investigate whether semaphorin-3A (Sema3A) is involved in the regulation of RGC polarity and Sema3A protein expression.

Methods

Cultured primary RGCs were treated with Fc-Sema3A or Sema3A siRNA or transfected with purified miR-30b recombinant adenoassociated virus (rAAV). The polarity of the RGCs was observed with immunofluorescence. A western blot analysis of phosphorylated protein kinase A (p-PKA), the downstream effector molecule phosphorylated glycogen synthase kinase 3 beta (GSK-3β), and collapsing response mediator protein 2 (CRMP2) was performed.

Results

We found that Sema3A could statistically significantly promote dendritic branching while inhibiting the growth of axons in RGCs. miR-30b overexpression and Sema3A siRNA could statistically significantly promote the growth of axons while inhibiting the growth of dendrites from RGCs. Additionally, miR-30b could restrain the expression of Sema3A protein and its downstream PKA/GSK-3β/CRMP2 signaling pathways.

Conclusions

The results indicate that Sema3A promotes dendritic growth and inhibits axonal growth, which is not conducive to the early repair of optic nerve injury. The overexpression of miR-30b can overcome this problem, and may represent a new target for the treatment of nerve injury and regeneration in the future.

Vitamin D-supplemented yogurt drink reduces Candida infections in a paediatric intensive care unit: a randomised, placebo-controlled clinical trial

BACKGROUND

The prevalence of Candida infections in paediatric intensive care units (PICUs) has dramatically increased as a result of resistance to conventional anti-fungal treatments. Because vitamin D has been shown to exhibit fungicidal activity against Candida infection in an in vitro antimicrobial screening, we aimed to investigate the effect of vitamin D on Candida infections in the PICU.

METHODS

Four hundred sixteen eligible children aged between 12 months to 5 years old admitted to the PICU, who were on broad-spectrum antibiotic therapy, participated in the study. Patients were randomly assigned to two study groups, receiving a plain yogurt drink (placebo group) or supplemented with 300 IU day^-1 vitamin D (VD group). Primary outcome was defined as the incidences of Candida colonisation (Candida isolated from rectal swab) 14 days after enrollment. Secondary outcome measures were Candida growth in blood (candidaemia) and urine (candiduria).

RESULTS

The prevalence of candiduria as well as candidaemia was significantly lower in the VD-treated group (26 cases) than in the placebo group (62 cases). The mean (SD) length of PICU stay was obviously lowered in the VD group [11.8 (1.2) days] compared to the placebo group [15.2 (2.3 days)], whereas cases of patient death were similar between the two groups.

CONCLUSIONS

Supplementation of vitamin D effectively reduces infections of Candida in children who were critically ill and on broad-spectrum antibiotic treatment.

Intractable and dramatic diarrhea in liver transplantation recipient with vasoactive intestinal peptide-producing tumor after split liver transplantation: a case report

Diarrhea after liver transplantation is a common complication. Vasoactive intestinal peptide-producing tumor (VIPoma) is a rare cause of watery diarrhea; 80% of such tumors occur in the pancreas, but it is rare in liver. Hypersecretion of vasoactive intestinal polypeptide can stimulate intestinal water and electrolyte secretion, and patients with VIPoma present with watery diarrhea, hypokalemia, and dehydration. Here we report on a 50-year-old man who presented with a 7-month history of watery diarrhea. He had undergone an orthotopic split-liver transplantation for hepatocellular carcinoma in November 2011. Two months after the liver transplantation, he presented with watery diarrhea, dehydration, and hypokalemia. Antibiotics, immunosuppressive drugs modification, antidiarrheal agents, antispasmodics, adsorbents, and fasting were alternately used to control the diarrhea, but his symptoms remained unchanged. A chromogranin examination, a marker of pancreatic neuroendocrine neoplasm, was positive in the third month of the diarrhea history and VIPoma was considered. Treatment with somatostatin immediately controlled the diarrhea, but the primary lesion could not be identified even after corresponding examinations were completed. In the ninth month of diarrhea, a 1 × 1-cm lesion was detected in the right liver by ultrasonography. Radiofrequency ablation was performed, and the diarrhea stopped. Seventeen months later, the chromogranin level decreased to normal and the patient was asymptomatic. Neither the recipient sharing the other liver portion nor the donor presented with any symptoms, so we wondered how the tumor occurred. It is possible that a small VIPoma lesion existed in the liver donor before the transplantation, and that the immunosuppressive drugs induced tumor development.

Applications of the line-of-response probability density function resolution model in PET list mode reconstruction

Resolution degradation in PET image reconstruction can be caused by inaccurate modeling of the physical factors in the acquisition process. Resolution modeling (RM) is a common technique that takes into account the resolution degrading factors in the system matrix. Our previous work has introduced a probability density function (PDF) method of deriving the resolution kernels from Monte Carlo simulation and parameterizing the LORs to reduce the number of kernels needed for image reconstruction. In addition, LOR-PDF allows different PDFs to be applied to LORs from different crystal layer pairs of the HRRT. In this study, a thorough test was performed with this new model (LOR-PDF) applied to two PET scanners-the HRRT and Focus-220. A more uniform resolution distribution was observed in point source reconstructions by replacing the spatially-invariant kernels with the spatially-variant LOR-PDF. Specifically, from the center to the edge of radial field of view (FOV) of the HRRT, the measured in-plane FWHMs of point sources in a warm background varied slightly from 1.7 mm to 1.9 mm in LOR-PDF reconstructions. In Minihot and contrast phantom reconstructions, LOR-PDF resulted in up to 9% higher contrast at any given noise level than image-space resolution model. LOR-PDF also has the advantage in performing crystal-layer-dependent resolution modeling. The contrast improvement by using LOR-PDF was verified statistically by replicate reconstructions. In addition, [(11)C]AFM rats imaged on the HRRT and [(11)C]PHNO rats imaged on the Focus-220 were utilized to demonstrated the advantage of the new model. Higher contrast between high-uptake regions of only a few millimeter diameter and the background was observed in LOR-PDF reconstruction than in other methods.

Evaluation of bias and variance in low-count OSEM list mode reconstruction

Statistical algorithms have been widely used in PET image reconstruction. The maximum likelihood expectation maximization reconstruction has been shown to produce bias in applications where images are reconstructed from a relatively small number of counts. In this study, image bias and variability in low-count OSEM reconstruction are investigated on images reconstructed with MOLAR (motion-compensation OSEM list-mode algorithm for resolution-recovery reconstruction) platform. A human brain ([(11)C]AFM) and a NEMA phantom are used in the simulation and real experiments respectively, for the HRRT and Biograph mCT. Image reconstructions were repeated with different combinations of subsets and iterations. Regions of interest were defined on low-activity and high-activity regions to evaluate the bias and noise at matched effective iteration numbers (iterations × subsets). Minimal negative biases and no positive biases were found at moderate count levels and less than 5% negative bias was found using extremely low levels of counts (0.2 M NEC). At any given count level, other factors, such as subset numbers and frame-based scatter correction may introduce small biases (1-5%) in the reconstructed images. The observed bias was substantially lower than that reported in the literature, perhaps due to the use of point spread function and/or other implementation methods in MOLAR.

Direct pathogen detection from swab samples using a new high-throughput sequencing technology

The detection of emerging infectious diseases has been a continuing concern, especially with the novel influenza A (H1N1) viral pandemic of 2009. In the present study, we validated a ‘second-generation’ parallel sequencing platform for viral detection in swab samples collected during recent influenza virus infections in Beijing. This operation yielded millions of valid reads per sample and resulted in an almost complete spectrum of nucleotide information. Importantly, novel A (H1N1) and seasonal A (H3N2) influenza virus-derived sequences were detected without prior knowledge or use of genetic information in advance, suggesting that this approach could be a valuable tool for diagnosing emerging infectious diseases.

CF mediated G1 arrest is associated with induction of p27(Kip1) and inhibition of cyclin D1 expression in human hepatoma HepG2 cells

CF is a kind of diterpenoid which was first isolated and purified from Chinese tropical plants by our laboratory. Our previous works have demonstrated it could inhibit the proliferation of several malignant tumor cell lines and stimulate them to differentiate to normal cells. In this article we investigated the effect of CF on human hepatocellulor carcinoma HepG2 cell viability, differentiation, cell cycle distribution and G1 cell cycle related genes expression. We also detected the effect of retinoic acid (RA) which was used as positive control and the effect of combination CF+RA. Our data suggested that CF could be useful to induce growth arrest and differentiation in HepG2 cell lines, and could reverse the transformed phenotype. This anti-tumor effect was due to G1 arrest in cell cycle which was associated with an increase of p27(Kip1) and a decrease of cyclin D1 expression, so CF might be a useful targeted therapy strategy for HCC. Results also showed RA has a different mechanism from CF on G1 arrest, and CF has not synergistic anti-tumor effect with RA on HepG2 treatment.

Synthesis of RGD containing peptides and their vasodilation effect

APLRV, SLRR, RGDS, and RGDF were synthesized by use of the solution method via the corresponding protective intermediates. After fragment condensation and deprotection, APLRVRGDS, APLRVRGDF, SLRRRGDS, and SLRRRGDF were obtained. The effect of these RGD containing peptides on rat aortic strips pretreated with noradrenaline (NE) were observed. The relaxing extents of contracted strips for them at three doses (10(-5) mol/L, 10(-6) mol/L and 10(-7) mol/L) indicated that, in a few cases, this kind of combination of these fragments may enhance the desirable activity.

Development of Female Contraceptive Vaccine Through DNA Inoculation of Human Chorionic Gonadotropin Beta Subunit (hCGß)

Human chorionic gonadotropin (hCG) has been considered as a primary target molecule for a contraceptive vaccine by the World Health Organization because of its physiological and temporal specificity. hCG is an essential factor for the successful implantation and establishment of early pregnancy. For a decade, the most advanced works in development of a contraceptive vaccine have been concentrated on polypeptide based vaccines targeted directly against hCG. Although many studies have reached the stage of clinical testing using a number of prototype vaccines based on different parts of hCG molecule, their efficacy has been disappointing (1-4).

Concordant induction of cyclin E and p21cip1 in differentiated keratinocytes by the human papillomavirus E7 protein inhibits cellular and viral DNA synthesis

Productive infections by human papillomaviruses (HPVs) occur only in differentiated keratinocytes in squamous epithelia in which the HPV E7 protein reactivates the host DNA replication machinery to support viral DNA replication. In a fraction of the differentiated keratinocytes, E7 also posttranscriptionally induces p21Cip1, which is distributed in a mutually exclusive manner with unscheduled cellular DNA synthesis. In this study, double immunofluorescence labeling unexpectedly revealed that E7 caused a concordant accumulation of both cyclin E and p21Cip1 to high levels in patient papillomas and in organotypic cultures of primary human keratinocytes. The induction of cyclin E is mutually exclusive with unscheduled cellular DNA synthesis or abundant viral DNA. These novel virus-host interactions in differentiated keratinocytes are in contrast to previous observations made in submerged proliferating cultures, in which HPV E7 induces cyclin E and overcomes p21Cip1 inhibition of S-phase entry. We propose that an appropriately timed induction of cyclin E/cyclin-dependent kinase 2 by HPV E7 in postmitotic cells enables S-phase reentry and HPV DNA amplification, whereas prematurely induced cyclin E stabilizes p21Cip1 protein, which then inhibits cyclin E/cyclin-dependent kinase 2. Consequently, cyclin E and p21Cip1 both fail to turn over, and DNA synthesis does not occur.

Post-transcriptional induction of p21cip1 protein by human papillomavirus E7 inhibits unscheduled DNA synthesis reactivated in differentiated keratinocytes

Productive infection by human papillomaviruses (HPVs) occurs only in differentiated squamous epithelial cells in papillomas, condylomata, and low grade intraepithelial neoplasias. Host DNA replication is reactivated in a fraction of terminally differentiated keratinocytes in benign human lesions and in organotypic raft cultures of primary human keratinocytes (PHKs) transduced with retroviruses expressing HPV-18 E7 oncogene from its native upstream regulatory region (URR). Thus the natural function of E7 protein, which inactivates pRB family proteins, is to induce host genes essential to support viral DNA replication in post-mitotic cells. Using this raft culture model system, we show that HPV-18 URR-E7 induces the universal cyclin-dependent kinase inhibitor p21cip1 protein in a fraction of differentiated PHKs. Induction is mediated by posttranscriptional mechanisms independent of p53. Double immunofluorescence studies demonstrate that, in raft cultures and in laryngeal papillomas, p21cip1 induction and reactivated host DNA synthesis take place in a mutually exclusive manner in PCNA-positive, differentiated keratinocytes. We suggest that p21cip1 induction effectively blocks unscheduled DNA synthesis reactivated by E7. These results begin to explain the inverse relationship between p21cip1 induction and HPV activities previously observed in a spectrum of benign lesions regardless of HPV types present.

STEP--a trial-and-error procedure for crystal structure determination. II. The determination of two small protein structures

This paper describes the difficulties in the process of using the trial-and-error SYSTEM90 program to determine ab initio the structures of two small proteins App [Woolfson & Yao (1990). Acta Cryst. A46, 409-413] and rubredoxin [Sheldrick et al. (1993). Acta Cryst. D49, 18-23] with high-resolution data. Some strategies for overcoming the difficulties are discussed and the upgraded SYSTEM95 program was used successfully to determine the two structures. The most characteristic feature of this structure-determination process is that the two proteins are treated as unknown structures with only their chemical compositions and high-resolution data sets known. A new figure of merit R(sc), replacing the old figure of merit, XDFOM, is quite effective in picking out a good set of phases in the multi-solution stage when the phases are overconsistent. Controlling the Fourier recycling technique and the residuals can separate the mixture of structures and the enantiomorph and finally give one absolute structure. The results are compared with known structures to verify their reliability.

Post-transcriptional induction of p21cip1 protein in condylomata and dysplasias is inversely related to human papillomavirus activities

Infections of the genital and oral epithelia by human papillomaviruses cause condylomata, papillomas, and squamous intraepithelial neoplasms, some of which can progress to invasive cancers. We describe an induction of p21cip1/WAF1/sdi1 protein in a fraction of the spinous cells in benign lesions and in cervical intraepithelial neoplasia grades I and II. The induction appears to be post-transcriptional and independent of p53. p21cip1 antigen-positive cells were sporadic in cervical intraepithelial neoplasia III and rare and focal in carcinomas. In contrast, p21cip1 protein was below or at the threshold of detection in the differentiated cells of normal squamous epithelia from different body sites despite an up-regulation of p21cip1 RNA. In cervical intraepithelial neoplasias from patients who were also positive for the human immunodeficiency virus, there was an additional increase in p21cip1 RNA in the upper spinous cells without concomitant p21cip1 protein induction. A consistent inverse relationship was observed between the p21cip1 protein induction and abundant human papillomavirus DNA and RNAs. We propose that p21cip1 protein induction is a novel host response that inhibits viral DNA replication and thus prevents elevated viral transcription. This hypothesis can partly account for the heterogeneity and the differentiation-dependent viral activities commonly observed in benign human papillomavirus lesions.

[Analysis of chromosome karyotype of Lycium chinense Mill]

The chromosome karyotypes of wild Lycium chinese and its cultivated breeds for vegetable have been studied. The Chromosome 12 of both has a satellite. The former, with 24 chromosomes and 1B karyotype, is a diploid and its karyotype formula is 2n = 2x = 24 = 18m + 6sm. The chromosome number of the latter is 48. As a tetrploid, it has 2B karyotype and a karyotype formula 2n = 4x = 48 = 36m + 12sm.

Incremental iron overload during reperfusion progressively augments oxidative injury

OBJECTIVE

To determine if a relationship exists between the extent of iron-catalyzed injury and the degree of tissue iron overload during reperfusion.

METHODS

To selectively increase tissue iron only during early reperfusion, isolated, buffer perfused rabbit hearts were exposed to 20 microM Fe(2+)-100 microM ADP during the last 3 minutes of ischemia and the initial 4 minutes of reperfusion. Control groups were exposed to ADP and iron-ADP regimens that did not increase intracellular iron. All the hearts received 30 minutes of normothermic global ischemia and 30 minutes of reperfusion. Heart function was monitored continuously throughout each experiment. Tissue iron and biochemical markers were analyzed at the end of experiments.

RESULTS

Hemodynamic recovery was decreased and tissue lipid peroxide levels were increased in the 20 microM Fe(2+)-100 microM ADP group compared to controls. The recoveries of developed pressure and positive/negative dP/dT at 30 minutes of reperfusion were negatively correlated with tissue iron levels, while cytosol and membrane lipid peroxide levels correlated positively with the iron levels during reperfusion.

CONCLUSION

The extent of oxidative injury during reperfusion was directly related to the tissue iron burden present during reperfusion. Increased lipid peroxidation was the principal chemical marker of iron-catalyzed injury.

[Quality of Chinese drug zicao]

Roots, root cortices and root corks from 6 species of Boraginaceae are used as zicao in commercial crude drugs. This paper reports the determination of naphthaquinone pigments (such as total pigments, beta, beta-dimethylacryshikonin, acetylshikonin and shikonin) in 12 samples of 6 plants. The quality of various drugs was evaluated by determining the contents of the above principles.