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Bing Shen

Publications and source records attributed to Bing Shen.

17 recordsLinked to original sources
PubMed2024

The NRF2-CARM1 axis links glucose sensing to transcriptional and epigenetic regulation of the pentose phosphate pathway in gastric cancer.

Cancer cells autonomously alter metabolic pathways in response to dynamic nutrient conditions in the microenvironment to maintain cell survival and proliferation. A better understanding of these adaptive alterations may reveal the vulnerabilities of cancer cells. Here, we demonstrate that coactivator-associated arginine methyltransferase 1 (CARM1) is frequently overexpressed in gastric cancer and predicts poor prognosis of patients with this cancer. Gastric cancer cells sense a reduced extracellular glucose content, leading to activation of nuclear factor erythroid 2-related factor 2 (NRF2). Subsequently, NRF2 mediates the classic antioxidant pathway to eliminate the accumulation of reactive oxygen species induced by low glucose. We found that NRF2 binds to the CARM1 promoter, upregulating its expression and triggering CARM1-mediated hypermethylation of histone H3 methylated at R arginine 17 (H3R17me2) in the glucose-6-phosphate dehydrogenase gene body. The upregulation of this dehydrogenase, driven by the H3R17me2 modification, redirects glucose carbon flux toward the pentose phosphate pathway. This redirection contributes to nucleotide synthesis (yielding nucleotide precursors, such as ribose-5-phosphate) and redox homeostasis and ultimately facilitates cancer cell survival and growth. NRF2 or CARM1 knockdown results in decreased H3R17me2a accompanied by the reduction of glucose-6-phosphate dehydrogenase under low glucose conditions. Collectively, this study reveals a significant role of CARM1 in regulating the tumor metabolic switch and identifies CARM1 as a potential therapeutic target for gastric cancer treatment.

Stomach Neoplasms↗
PubMed2006

Cross-talk of the renin-angiotensin and kallikrein-kinin systems.

The renin-angiotensin (RAS) and kallikrein-kinin (KKS) systems play a key role in multiple physiological and pathophysiological conditions, including growth and development, inflammation, blood pressure regulation and control of renal function. In many instances, kinins and angiotensin II work together, e.g., during development, whereas they oppose each other's actions in the regulation of vascular tone and renal function. The RAS and KKS systems also interact at multiple levels, so that changes in the activity of one system greatly impact the activity of the other. The purpose of this brief review is to highlight recent knowledge regarding interactions at the cellular and molecular levels between the two systems, with an emphasis on the coordinate developmental regulation of these phylogenetically conserved vasoactive systems.

Animals↗
PubMed2006

Trend and disease burden of bacillary dysentery in China (1991-2000).

OBJECTIVE: We aimed to determine the burden of bacillary dysentery in China, its cross-regional variations, trends in morbidity and mortality, the causative bacterial species and antimicrobial resistance patterns. METHODS: We extracted and integrated governmental statistics and relevant medical literature published from 1991 to 2000. Data were also collected from one general hospital each for the six provinces and Jin-an district, Shanghai, representative of six geographical regions and a modern city. FINDINGS: In 2000, 0.8-1.7 million episodes of bacillary dysentery occurred of which 0.5 to 0.7 million were treated at health-care facilities and 0.15-0.20 million patients were hospitalized. The highest morbidity and mortality rates were among the youngest and oldest age groups. Bacillary dysentery peaked during the summer months. The major causative species was Shigella flexneri (86%) and the predominant S. flexneri serotype was 2a (80%). About 74-80% of Shigella isolates remained susceptible to fluorinated quinolones. CONCLUSION: We conclude that while morbidity and mortality due to bacillary dysentery has decreased considerably in China in the past decade due to increasing access to affordable health care and antibiotics, a considerable burden exists among the youngest and oldest age groups and in regions with low economic development. We suggest that while a vaccine would be effective for short- and medium-term control of bacillary dysentery, improved water supply, sanitation, and hygiene are likely to be required for long-term control.

Adolescent↗
PubMed2006

[Pathology of AIDS-related lymphadenopathy and its relationship to expression of CD4 + CD25 + regulatory T cells in lymphoid node tissue].

OBJECTIVE: To observe the pathology of AIDS-related lymphadenopathy and its relationship to the expression and distribution of CD4 + CD25 + regulatory T cells in lymphoid node tissue. METHODS: Totally 22 biopsy and 13 autopsy lymphoid node tissues from HIV-positive patients were examined under microscopy and pathological staging was performed. Specific marker for CD4 + CD25 + regulatory T cells in lymphoid node tissue was detected with anti-Foxp3 monoclonal antibody by immunohistochemistry. RESULTS: Among all the 35 specimens, 5, 4, 14, and 12 specimens were histopathologically staged from 1 to 4, respectively. FoxP3 were detected in all lymphoid node tissues. The distribution of FoxP3-positive lymphocytes were mainly in intermediate zone of follicle and cortical area in stages 1 and 2. The counts of FoxP3-positive lymphocytes remarkably decreased in stages 3 and 4, following depletion of lymphocytes. CONCLUSIONS: CD4 + CD25 + regulatory T cells exist in lymphoid node tissue of patients with HIV infection. Their amounts decrease or deplete along with the progression of AIDS-related lymphadenopathy.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Blocking effect and crystal structure of natrin toxin, a cysteine-rich secretory protein from Naja atra venom that targets the BKCa channel.

Cysteine-rich secretory proteins (CRISPs) are widespread in snake venoms. Some members of these CRISPs recently have been found to block L-type Ca(2+) channels or cyclic nucleotide-gated ion (CNG) channels. Here, natrin purified from Naja atra venom, a member of the CRISP family, can induce a further contractile response in the endothelium-denuded thoracic aorta of mouse which has been contracted by a high-K(+) solution. Further experiments show it can block the high-conductance calcium-activated potassium (BK(Ca)) channel in a concentration-dependent manner with an IC(50) of 34.4 nM and a Hill coefficient of 1.02, which suggests that only a single natrin molecule is required to bind an ion channel to block BK(Ca) current. The crystal structure of natrin displaying two domains in tandem shows its cysteine-rich domain (CRD) has relatively independent flexibility, especially for the C-terminal long loop (loop I) of CRD to participate in the interface of two domains. On the basis of previous studies of CNG channel and L-Ca(2+) channel blockers, and the sequence and structural comparison of natrin and stecrisp, the deviation of the vital loop I of CRD is suggested to contribute to different effects of some CRISPs in protein-protein interaction.

Amino Acid Sequence↗
PubMed2005

Biosafety level 3 laboratory for autopsies of patients with severe acute respiratory syndrome: principles, practices, and prospects.

BACKGROUND: During the outbreak of the emergent severe acute respiratory syndrome (SARS) infection, >30% of the approximately 8000 infected persons were health care workers. The highly infectious nature of SARS coronavirus (SARS-CoV) compelled our pathologists to consider biosafety issues in the autopsy room and for tissue processing procedures. METHODS: A specially designed biosafety level 3 (BSL-3) autopsy laboratory was constructed and divided into a clean area, a semicontaminated area, a contaminated area, and 2 buffer zones. High-efficiency particulate air filters were placed in the air supply and exhaust systems. Laminar air flow was from the clean areas to the less clean areas. The negative pressures of the contaminated, semicontaminated, and clean areas were approximately -50 pa, -25 pa, and -5 pa, respectively. Personal protective equipment, including gas mask, impermeable protective clothing, and 3 layers of gloves worn during autopsies; the equipment was decontaminated before it was allowed to exit the facility. Strict BSL-3 practices were followed. RESULTS: When a given concentration of particulate sarin simulant was introduced into the contaminated area, it could not be detected in either the semicontaminated area or clean area, and particles >0.3 microm in size were not detected in the exhaust air. A total of 16 complete postmortem examinations for probable and suspected SARS were performed during a 2-month period. Of these, 7 reported confirmed cases of SARS. None of the 23 pathologists and technicians who participated in these autopsies was infected with SARS-CoV. CONCLUSIONS: Our experience suggests that BSL-3 laboratory operating principles should be among the special requirements for performing autopsies of contaminated bodies and that they can safeguard the clinicians and the environment involved in these procedures.

Autopsy↗
PubMed2005

A uniquely preserved Ediacaran fossil with direct evidence for a quilted bodyplan.

Ediacara fossils are among the oldest known macroscopic and complex life forms. Their bodyplan, ecology, and phylogenetic affinities have been controversial. On the basis of taphonomic observations, Seilacher [Seilacher, A. (1989) Lethaia 22, 229-239] proposed that the core elements of the Ediacara biota, the vendobionts, were constructed with serially or fractally arranged quilts or tube-like units. However, anatomy of quilt walls has been rarely reported, because most Ediacara fossils are preserved as casts and molds in siliciclastic rocks with inadequate morphological resolution. Here, we report an Ediacara form, uniquely preserved in situ and in three dimensions with its organic walls cast by early diagenetic calcite, from bituminous limestone of the 551- to 542-mega-annum Dengying Formation of South China. Despite diagenetic tampering, serial sections show that the Dengying form consists of biserially arranged, tube-like quilts, each with two vertical side walls, a floor, a roof, and an open distal end. Three-dimensional morphological complexity of the Dengying form excludes a microbial interpretation but is broadly consistent with vendobionts. Unlike classic frondose vendobionts sensu Seilacher, however, the Dengying form probably lacked a smooth margin and had distally open quilts. It probably lived procumbently at or near the water-sediment interface and shows evidence for substrate utilization. Despite its uncertain phylogeny, ontogeny, and functional biology, the Dengying form adds to Ediacaran biodiversity, places key constraints on the ecology and extinction of Ediacara organisms, and points to the need to explore an alternative taphonomic window for Ediacara biology.

Anatomy↗
PubMed2005

Connections between integrins and Rac GTPase pathways control gonad formation and function in C. elegans.

The integrins are a family of alphabeta heterodimeric transmembrane receptors that link extracellular matrix (ECM) proteins to the cytoskeleton and orchestrate cell behaviors. It's been suggested that integrins interact with Rho family small GTPases, such as Rho and Rac. We took advantage of a C. elegans nematode line expressing HA-betatail, a beta integrin transgene inhibiting the functions of endogenous integrins, to determine the combined effects of reducing PAT-3 beta integrin and Rac pathway activities. Double mutants of HA-betatail and unc-73, a guanine nucleotide exchange factor GEF for MIG-2/Rac, had body wall and vulval muscle abnormalities. On the other hand, HA-betatail combined with mutant CED-5, another Rac interacting protein, showed ovulation defects and sterility. RNA-mediated interference (RNAi) of pat-3 on Rac mutant backgrounds also affected gonad structure and function. These results show a functional link between integrins and Rac signaling in muscles and gonads. Furthermore, data showing distinct phenotypes of HA-betatail with unc-73 versus ced-5 suggest some tissue-specificity in the usage of Rac signaling pathways.

Animals↗
PubMed2005

Measuring blood flow velocities based on three image processing techniques.

The classification of microcirculation can be based on the size of the capillary and the velocity of the blood flow. For each type of microcirculation, the ad hoc method is required to measure the blood flow velocity. In this paper, the correlation method is used to measure blood flow velocity in the small-size capillary. The large-size capillaries are classified into three types based on the blood velocities, say low-speed, high-speed, and unstable one. The template-matching algorithm, the Fast Fourier Transform algorithm and a high-speed video camera measurement are used to measure the blood velocities corresponding to those three types of large-size capillary. It was shown by several experiments that fairly good results for different types of capillary may be obtained by using the proposed three image processing algorithms.

Algorithms↗
PubMed2005

[Ecological protection and sustainable utilization of Erhai Lake, Yunnan].

Economic development and increase of population pressure have caused a series of ecological environmental problems of Erhai Lake. These problems include: (1) Quickening of eutrophication process, (2) Decrease of water level and water resources, (3) Habitat deterioration of lakeside zone, and (4) Overfishing and slow depletion of aboriginal fish. Pollutant loading of Erhai Lake is as follows: COD(Cr) 3 008 t x a(-1), TP 137.31 t x a(-1), TN 1 426.35 t x a(-1). According to the mestrophic target of water quality, loading of nitrogen and phosphorus is far above environmental capacity of Erhai Lake. Erhai Lake is now in a pivotal and hypersensitive period of trophic states change, and the position is very critical. Therefore, some countermeasures to solve the problems are presented as follows: (1) Defining the dominant functions of Erhai Lake, (2) Paying attention to the adjustment of the industrial structure and distribution in the course of urbanization, (3) Setting up lakeside zone reserve, (4) Strengthening the control of tourism pollution, (5) Properly adjusting the water level of Erhai Lake, and (6) Some ecological engineering measures for water resources protection in the basin should be taken through collecting and treating of urban sewages, ecological rehabilitating of the main inflowing rivers, constructing of ecological agricultures and improving of rural environment, ecological restoring of aquatic ecosystem, and soil and water conservation.

China↗
PubMed2005

[A pathological study on liver tissues of patients with HIV infection].

OBJECTIVE: To study the pathological changes of the liver tissues of patients with HIV infection. METHODS: 14 biopsy and 12 autopsy liver tissues were examined histologically. HIV-1 related antigen of outer membrane protein gp120 and capsid protein p24 were examined with their corresponding monoclonal antibodies by immunohistochemistry. RESULTS: In the biopsy group, cytomegalic virus (CMV) infection was found in one (1/14) case, outer membrane protein gp120 and/or capsid protein p24 antigen were detected in Kupffer cells and in some of the lymphocytes in 11 cases. All the hepatocytes were negative for outer membrane protein gp120 and capsid protein p24 antigens. In the autopsy group, there were 5 (5/12) cases of liver tissues with CMV infection and 5 cases each with mycobacterium and Toxoplasma gondii infection. Capsid protein p24 was detected in liver tissues in 3 cases. CONCLUSION: There is HIV infection in liver tissue of patients with HIV. The rate of opportunistic infections in liver biopsy samples was lower than that in the autopsy liver tissues of patients with HIV.

Adult↗
PubMed2004

An increase in opening of BK(Ca) channels in smooth muscle cells in streptozotocin-induced diabetic mice.

AIM: To investigate the changes of function of large conductance of calcium-activated potassium channels (BK(Ca) channels) in thoracic aortic smooth muscle cells in early stage of streptozotocin (STZ)-induced diabetic C57BL/6J mice. METHODS: Vascular muscle tension in the isolated thoracic aortic rings of mice was compared, and the role of BK(Ca) channels in relaxation of isolated mice thoracic aortic rings induced by acetylcholine (ACh) was determined. Meanwhile, single vascular smooth muscle cells (VSMCs) were isolated by collagenase, and BK(Ca) currents were recorded by patch-clamp single channel recording technique in symmetric high potassium solution. RESULTS: Tetraethylammonium (TEA) 1 mmol/L, a selective calcium-activated potassium channel blocker, caused significant rightward shift in the concentration-response curves of ACh in the isolated thoracic aortic rings of diabetic mice and pD2 value of ACh-induced relaxation was decreased notably after TEA treatment [(6.3+/-0.4) vs (6.9+/-0.5), n=10 rings from 7 mice, P<0.01]. But pD2 value of ACh-induced relaxation in age-matched control mice did not change in presence and absence of TEA 1 mmol/L [(6.4+/-0.15) vs (6.5+/-0.5), n=7 rings from 6 mice, P>0.05]. Furthermore, conductance of BK(Ca) channels in single thoracic aortic smooth muscle cells was decreased [(199+/-15) pS, n=10 cells from 7 mice vs (266+/-11) pS, n=12 cells from 6 mice, P<0.01], but probability of open of BKCa channels was increased [(0.51+/-0.28) vs (0.11+/-0.06), n=6 cells from 6 mice, P<0.01], and the mean closed time in diabetic mice was reduced [(15+/-15) vs (132+/-98), n=6 cells from 6 mice, P<0.05]. CONCLUSION: The opening of BK(Ca) channels was increased in thoracic aortic smooth muscle cells in the early stage of STZ-induced diabetic C57BL/6J mice by reducing mean closed time, but the conductance of BK(Ca) channels was decreased.

Acetylcholine↗
PubMed2003

Mechanism underlying enhanced endothelium-dependent vasodilatation in thoracic aorta of early stage streptozotocin-induced diabetic mice.

AIM: To investigate the mechanism of the enhanced endothelium-dependent vasodilatation in thoracic aorta of the early stage streptozotocin (STZ)-induced diabetic C57BL/6J mice. METHODS: Radioimmunity was used to detect the metabolite of prostaglandin I2 (PGI2), 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), in the blood serum. Vascular muscle tension and phenylephrine (PE)-induced rhythmic activity in the isolated thoracic aorta of mice were also compared. RESULTS: 6-Keto-PGF1 alpha in the serum was significantly higher in STZ-induced diabetic mice than age-matched controls [(1.8+/-1.0) microg./L vs (0.5+/-0.3) microg/L, P<0.01]. PE induced rhythmic activity in both diabetic and control mouse aorta but the amplitude was markedly higher in diabetic mice than in controls [(4.9+/-1.7) % vs (12+/-5) %, P<0.01]. PE, high K+ solution-induced contraction, and acetylcholine (ACh)-induced relaxation [(56+/-10) % vs (81+/-8) %, P<0.01] were notably enhanced in diabetic mice than those in controls. Alone NG-nitro-L-arginine methyl ester (L-NAME) or 6-(phenylamino)-5,8-quinolinedione (LY-83583) abolished the rhythmic activity and ACh-induced relaxation in controls but only partially inhibited them in diabetic mice. Indomethacin did not affect rhythmic activity but depressed ACh-induced relaxation. L-NAME plus indomethacin significantly depressed the rhythmic activity and ACh-induced relaxation than L-NAME alone (P<0.01). Furthermore tetraethylammonium plus L-NAME abolished them in diabetic mice. CONCLUSION: The mechanism that enhanced endothelium-dependent vasodilatation in STZ-induced diabetic mice is due to enhanced production of PGI2 and endothelium-derived hyperpolarizing factor (EDHF). The phenomena maybe only take place in early stage of diabetic mice.

6-Ketoprostaglandin F1 alpha↗
PubMed2003

[The changes of plasma levels of brain natriuretic peptides in evaluation of treatment responses in chronic heart failure].

OBJECTIVE: To evaluate the changes of plasma levels of brain natriuretic peptides in patient with chronic heart failure (CHF) and the effect of beta-blockers (BB) on CHF. METHODS: We enrolled 33 patients with CHF, NYHAII-III, age 19 - 76 (57.5 +/- 15.8) years. Plasma levels of atrial and brain natriuretic peptides (ANP, BNP) were measured with radioimmunoassay and immunoradiometric assay in these patients. All the patients were assigned to 3 groups as follows: standard therapy group 12 cases (receiving ACEI + digoxin + diuretic), metoprolol treatment group 10 cases (receiving metoprolol in addition to the standard therapy), carvedilol treatment group 11 cases (receiving carvedilol in additional to the standard therapy). These patients were treated for three months, the therapeutic effects were assessed by change of plasma levels of ANP and BNP. RESULTS: Plasma levels of ANP and BNP were significantly elevated in CHF patients. After treatment, ANP and BNP plasma levels both decreased significantly. In patients receiving beta-blockers, BNP plasma levels decreased most significantly. CONCLUSION: BNP plasma level is a good marker to reflect left ventricular function. Measurement of BNP plasma level is useful to monitor the change of left ventricular function and to evaluate the effect of treatment with beta-blockers.

Adrenergic beta-Antagonists↗
PubMed2002

[Distribution of CSF1PO TPOX and TH01 loci in five minority populations in Yunnan of China].

OBJECTIVE: To investigate the distribution of CSF1PO, TPOX and TH01 in 5 minority populations only resided in Yunnan province. METHODS: DNA extraction from bloods and multiplex amplification of CSF1PO, TPOX and TH01 were carried out. The technique of denaturing polyacrylamide gel electrophoresis and silver staining method were used. RESULTS: The data on the distribution of allele frequencies of 3 loci(CSF1PO, TPOX and TH01) in Achang Deang Bulang Pumi and Jino were collected and analyzed. CONCLUSION: The allele distribution of the loci were in good agreement with the Hardy-Weinberg equibrium. A satisfactory result was obtained and some significant genetics differences were noticed in different populations.

Alleles↗
PubMed2002

[Comparative study on graft of autogeneic iliac bone and tissue engineered bone].

OBJECTIVE: To compare the clinical results of repairing bone defect of limbs with tissue engineering technique and with autogeneic iliac bone graft. METHODS: From July 1999 to September 2001, 52 cases of bone fracture were randomly divided into two groups (group A and B). Open reduction and internal fixation were performed in all cases as routine operation technique. Autogeneic iliac bone was implanted in group A, while tissue engineered bone was implanted in group B. Routine postoperative treatment in orthopedic surgery was taken. The operation time, bleeding volume, wound healing and drainage volume were compared. The bone union was observed by the X-ray 1, 2, 3, and 5 months after operation. RESULTS: The sex, age and disease type had no obvious difference between groups A and B. all the wounds healed with first intention. The swelling degree of wound and drainage volume had no obvious difference. The operation time in group A was longer than that in group B (25 minutes on average) and bleeding volume in group A was larger than that in group B (150 ml on average). Bone union completed within 3 to 7 months in both groups. But there were 2 cases of delayed union in group A and 1 case in group B. CONCLUSION: Repair of bone defect with tissue engineered bone has as good clinical results as that with autogeneic iliac bone graft. In aspect of operation time and bleeding volume, tissue engineered bone graft is superior to autogeneic iliac bone.

Adolescent↗