Introduction: In view of the number of sickle cell patients and due to a low production of descriptive studies, we decided to determine the prevalence of genes S and C of the disease in the Zinder region. The objectiv...Introduction: In view of the number of sickle cell patients and due to a low production of descriptive studies, we decided to determine the prevalence of genes S and C of the disease in the Zinder region. The objective was to contribute to improving the management of sickle cell disease in Zinder. Methodology: This was a systematic screening by the “Sickle Scan” test of any blood donor admitted to the Zinder Regional Blood Transfusion Center during the 6-month study period, from January to June 2023. The Sickle Scan is a qualitative lateral flow chromatography immunoassay using whole blood samples that aid in the rapid diagnosis of sickle cell disease. Results: The study was carried out on 613 samples during the period concerned. The frequency of sickle cell genes was 26.9% (n = 165) in all samples collected, with 23.1% (n = 142) and 3.8% (n = 23) for the S gene and the C gene, respectively. The 18 - 30 age group was the most represented with 64.4% (n = 395) cases. The median age of blood donors was 26 years ± 10 years (min = 18 years/max = 60 years). The sex ratio was 2.5. Donors of Nigerien nationality accounted for 84.1% (n = 516). There is a predominance of blood donors with an average monthly income between 34,000 and 70,000 CFA francs in 44.3% (n = 272), lived in permanent housing with drinking water supply. Sickle cell trait (SMA) was found in 22.5% (n = 138). Conclusion: The analysis of these results highlights a high frequency of the S gene for sickle cell disease. The population with an average monthly income is the most affected, with a male predominance.展开更多
Ensuring a high manufacturing test quality of an integrated electronic circuit mandates the application of a large volume test set. Even if the test data can be fit into the memory of an external tester, the consequen...Ensuring a high manufacturing test quality of an integrated electronic circuit mandates the application of a large volume test set. Even if the test data can be fit into the memory of an external tester, the consequent increase in test application time reflects into elevated production costs. Test data compression solutions have been proposed to address the test time and data volume problem by storing and delivering the test data in a compressed format, and subsequently by expanding the data on-chip. In this paper, we propose a scan cell positioning methodology that accompanies a compression technique in order to boost the compression ratio, and squash the test data even further. While we present the application of the proposed approach in conjunction with the fan-out based decompression architecture, this approach can be extended for application along with other compression solutions as well. The experimental results also confirm the compression enhancement of the proposed methodology.展开更多
Three types of osteoblast-like cells with different cnfigurations could be ob-tained through culturing fetal chicken calvaria in vitro. They were spindle-shaped cells,globular cells, and polygonal or squamous cells. W...Three types of osteoblast-like cells with different cnfigurations could be ob-tained through culturing fetal chicken calvaria in vitro. They were spindle-shaped cells,globular cells, and polygonal or squamous cells. With passage of culture time, there werechanges in configuration so that the spindle-shaped cells and the globular cells turnedgradually into squamous cells, in quantity which increased greatly to produce confluenceand multi-layer formation of cells, and in function as evidenced by emergence ofintracytoplasmic granules, reflecting collagen synthesis.展开更多
Nano-sized titanium oxide nanoparticles (TiO2 NPs) are widely used as a dye in food and cosmetics. TiO2 NPs are known to induce DNA damage when incorporated into cells. However, no bioassay is currently available to e...Nano-sized titanium oxide nanoparticles (TiO2 NPs) are widely used as a dye in food and cosmetics. TiO2 NPs are known to induce DNA damage when incorporated into cells. However, no bioassay is currently available to easily determine the cell incorporation of TiO2 NPs or related DNA damage, and to date, few studies have examined the different degrees of incorporation into cells according to the size of the TiO2 NPs particles and the presence or absence of cell specificity regarding DNA damage. This present study was therefore designed to examine COS7 cells that had incorporated TiO2 NPs using atmospheric scanning electron microscopy (ASEM). The results indicated that absorption of TiO2 NPs into cells and nuclear abnormalities had occurred. ASEM is a rapid and simple technique that enables the observation of samples immediately after fixation with glutaraldehyde and staining with phosphotungstic acid, and this method was suggested to be useful in screening for DNA damage.展开更多
Scanning Probe Microscopes (SPMs) observe specimen surfaces with probes by detecting the physical amount of a material between the cantilever and the surface. SPMs have a high resolution and can measure mechanical cha...Scanning Probe Microscopes (SPMs) observe specimen surfaces with probes by detecting the physical amount of a material between the cantilever and the surface. SPMs have a high resolution and can measure mechanical characteristics such as stiffness, adsorptive properties, and viscoelasticity. These features make it easy to identify the surface structure of complex materials;therefore, the use of SPMs has increased in recent years. Wood cell walls are primarily composed of cellulose, hemicellulose, and lignin. It is believed that hemicellulose and lignin surround the cellulose framework;however, their detailed formation remains unknown. Therefore, we observed wood cell walls via scanning probe microscopy to try to reveal the formation of the cellulose framework. We determined that the size of the cellulose microfibril bundle and hemicellulose lignin module composite was 18.48 nm based on topography and that the size of the cellulose microfibril bundle was 15.33 nm based on phase images. In the viscoelasticity image, we found that the viscoelasticities of each cell wall of the same cell were not the same. This is because the cellulose microfibrils in each cell wall lean in different directions. The angle between the leaning of the cellulose microfibril and the cantilever affects the viscoelasticity measurement.展开更多
Water plays a critical role on the performance, stability and lifetime of proton exchange membrane fuel cells(PEMFCs). The addition of poly tetrafluoroethylene(PTFE) to the gas diffusion layer, especially, the cat...Water plays a critical role on the performance, stability and lifetime of proton exchange membrane fuel cells(PEMFCs). The addition of poly tetrafluoroethylene(PTFE) to the gas diffusion layer, especially, the cathode side, would optimize the transportation of water, electron and gas and thus improve the performance of the fuel cell. But until now, the studies about directly applying the PTFE to the catalyst layer are rarely reported. In this paper, the membrane electrode is fabricated by using directly coating catalyst to the membrane method(CCM) and applying PTFE directly to the cathode electrode catalyst layer. The performance of the single cell is determined by polarization curves and durability tests. Electrochemical impedance spectroscopy(EIS) and scanning electron microscopy(SEM) techniques are used to characterize the electrochemical properties of PEMFC. Also the performance of a 10-cells stack is detected. Combining the performance and the physical-chemistry characterization of PEMFC shows that addition of appropriate content of PTFE to the electrode enhances the performance of the fuel cell, which may be due to the improved water management. Addition of appropriate content of PTFE enhances the interaction between the membrane and the catalyst layer, and bigger pores and highly textured structure form in the MEA, which favors the oxygen mass transfer and protons transfer in the fuel cell. While superfluous addition of PTFE covers the surface of catalysts and hindered the contact of catalyst with Nation, which leads to the reduction of electrochemical active area and the decay of the fuel cell performance. The proposed research would optimize the water management of the fuel cell and thus improve the performance of the fuel cell.展开更多
INTRODUCTIONThe endoplasmic reticulum(ER)consists of a complexsystem of tubules,lamellae,and flattened vesicles,andhas a variety of morphologies in different cells.It isbelieved to play a central role in the biosynthe...INTRODUCTIONThe endoplasmic reticulum(ER)consists of a complexsystem of tubules,lamellae,and flattened vesicles,andhas a variety of morphologies in different cells.It isbelieved to play a central role in the biosynthesis ofcholesterol,phospholipids, steroids, prostaglandins,展开更多
BACKGROUND: Surgeons are always concerned about the localization of pancreatic functioning islet cell tumor. If the tumor is accurately localized before operation, resection of the pancreatic body and tail without int...BACKGROUND: Surgeons are always concerned about the localization of pancreatic functioning islet cell tumor. If the tumor is accurately localized before operation, resection of the pancreatic body and tail without intention can be avoided. The purpose of this study was to evaluate spiral CT localization of pancreatic functioning islet cell tumors and CT techniques. METHODS: CT manifestations in 6 patients with clinically and pathologically proved pancreatic functioning islet cell tumors ware analyzed retrospectively. RESULTS: In 4 patients with insulinomas and 2 patients with glucagonomas, 5 were localized accurately by CT be- fore surgery and 1 was detected retrospectively. The en- hancement of tumors was greater than that of normal pan- creas in arterial phase and pancreatic parenchymal phase. Four patients showed mild high-density and 2, iso-density in the portal venous phase. CONCLUSION: Spiral CT multi-phase enhanced scan with 1.5 ml/kg contrast agent and 2-5 mm slice width can loca- lize functioning islet cell tumors accurately.展开更多
AIM: To investigate the effects of anti-fibrosis I herbal compound on intracellular Ca2+ in activated hepatic stellate cell (HSC) and to try to survey its molecular mechanism in treatment and prevention of hepatic fib...AIM: To investigate the effects of anti-fibrosis I herbal compound on intracellular Ca2+ in activated hepatic stellate cell (HSC) and to try to survey its molecular mechanism in treatment and prevention of hepatic fibrosis and portal hypertension.METHODS: The activated HSC line was plated on small glass cover slips in 24 wells culture dishes at a density of 5x106/mL, and incubated in RPMI-1640 media for 24 h.After the cells were loaded with Fluo-3/AM, intracellular Ca2+ was measured with laser scanning confocal microscopy (LSCM). The dynamic changes of intracellular Ca2+,stimulated by carbon tetrachloride, TGF-β1 antibody and the drug serum of anti-fibrosis I herbal compound and under orthogonal design were determined by LSCM. The effect of anti-fibrosis I herbal compound on intracellular Ca2+ was observed before and after the addition of TGF-β1antibody.RESULTS: The intracellular Ca2+ were significantly different in different dosage of carbon tetrachloride anti-fibrosis Iformula drug serum, TGF-β1 antibody and different turn of these substance, but their interval time between CCl4and TGF-β1 antibody, CCl4 and anti-fibrosis I drug serum had no influence on intracellular Ca2+. The result showed intracellular Ca2+ wasn't significantly different between rat serum without anti-fibrosis I and untreated group.After carbon tetrachloride stimulation, intracellular Ca2+ of activated HSC increased significantly when the dosage of CCl4 from 5 to 15 mmol/L, however, decreased significantly after stimulation by 5-20 μg/mL TGF-β1antibody or 5-20 mL/L drug serum. Moreover, before and after the addition of TGF-β1 antibody, intracellular Ca2+was significantly different. These results suggested that the molecular mechanism was independent of blocking TGF-β1 effects.CONCLUSION: Anti-fibrosis I herbal compound may treat hepatic fibrosis and decrease portal hypertension by inhibiting activated HSC contractility through decrease of intracellular Ca2+.展开更多
We succeeded in performing of hybrid Scanning Probe Microscopy (hybrid-SPM) in which mechanical-SPM andfluorescence microscopy are combined. This technique is able to measure simultaneously mechanical properties anddi...We succeeded in performing of hybrid Scanning Probe Microscopy (hybrid-SPM) in which mechanical-SPM andfluorescence microscopy are combined. This technique is able to measure simultaneously mechanical properties anddistribution of cytoskeletons of living cells by using green fluorescent protein. We measured evolution of both local elasticityand distributions of actin stress fibers in an identical fibroblast living in physiological conditions. The SPM experimentsrevealed that stiffer lines develop in living cells, which correspond to actin stress fibers. The elasticity of the actin stressfibers is as high as 100 kPa. We discuss mechanical effects on the development of actin filament networks.展开更多
文摘Introduction: In view of the number of sickle cell patients and due to a low production of descriptive studies, we decided to determine the prevalence of genes S and C of the disease in the Zinder region. The objective was to contribute to improving the management of sickle cell disease in Zinder. Methodology: This was a systematic screening by the “Sickle Scan” test of any blood donor admitted to the Zinder Regional Blood Transfusion Center during the 6-month study period, from January to June 2023. The Sickle Scan is a qualitative lateral flow chromatography immunoassay using whole blood samples that aid in the rapid diagnosis of sickle cell disease. Results: The study was carried out on 613 samples during the period concerned. The frequency of sickle cell genes was 26.9% (n = 165) in all samples collected, with 23.1% (n = 142) and 3.8% (n = 23) for the S gene and the C gene, respectively. The 18 - 30 age group was the most represented with 64.4% (n = 395) cases. The median age of blood donors was 26 years ± 10 years (min = 18 years/max = 60 years). The sex ratio was 2.5. Donors of Nigerien nationality accounted for 84.1% (n = 516). There is a predominance of blood donors with an average monthly income between 34,000 and 70,000 CFA francs in 44.3% (n = 272), lived in permanent housing with drinking water supply. Sickle cell trait (SMA) was found in 22.5% (n = 138). Conclusion: The analysis of these results highlights a high frequency of the S gene for sickle cell disease. The population with an average monthly income is the most affected, with a male predominance.
文摘Ensuring a high manufacturing test quality of an integrated electronic circuit mandates the application of a large volume test set. Even if the test data can be fit into the memory of an external tester, the consequent increase in test application time reflects into elevated production costs. Test data compression solutions have been proposed to address the test time and data volume problem by storing and delivering the test data in a compressed format, and subsequently by expanding the data on-chip. In this paper, we propose a scan cell positioning methodology that accompanies a compression technique in order to boost the compression ratio, and squash the test data even further. While we present the application of the proposed approach in conjunction with the fan-out based decompression architecture, this approach can be extended for application along with other compression solutions as well. The experimental results also confirm the compression enhancement of the proposed methodology.
文摘Three types of osteoblast-like cells with different cnfigurations could be ob-tained through culturing fetal chicken calvaria in vitro. They were spindle-shaped cells,globular cells, and polygonal or squamous cells. With passage of culture time, there werechanges in configuration so that the spindle-shaped cells and the globular cells turnedgradually into squamous cells, in quantity which increased greatly to produce confluenceand multi-layer formation of cells, and in function as evidenced by emergence ofintracytoplasmic granules, reflecting collagen synthesis.
文摘Nano-sized titanium oxide nanoparticles (TiO2 NPs) are widely used as a dye in food and cosmetics. TiO2 NPs are known to induce DNA damage when incorporated into cells. However, no bioassay is currently available to easily determine the cell incorporation of TiO2 NPs or related DNA damage, and to date, few studies have examined the different degrees of incorporation into cells according to the size of the TiO2 NPs particles and the presence or absence of cell specificity regarding DNA damage. This present study was therefore designed to examine COS7 cells that had incorporated TiO2 NPs using atmospheric scanning electron microscopy (ASEM). The results indicated that absorption of TiO2 NPs into cells and nuclear abnormalities had occurred. ASEM is a rapid and simple technique that enables the observation of samples immediately after fixation with glutaraldehyde and staining with phosphotungstic acid, and this method was suggested to be useful in screening for DNA damage.
文摘Scanning Probe Microscopes (SPMs) observe specimen surfaces with probes by detecting the physical amount of a material between the cantilever and the surface. SPMs have a high resolution and can measure mechanical characteristics such as stiffness, adsorptive properties, and viscoelasticity. These features make it easy to identify the surface structure of complex materials;therefore, the use of SPMs has increased in recent years. Wood cell walls are primarily composed of cellulose, hemicellulose, and lignin. It is believed that hemicellulose and lignin surround the cellulose framework;however, their detailed formation remains unknown. Therefore, we observed wood cell walls via scanning probe microscopy to try to reveal the formation of the cellulose framework. We determined that the size of the cellulose microfibril bundle and hemicellulose lignin module composite was 18.48 nm based on topography and that the size of the cellulose microfibril bundle was 15.33 nm based on phase images. In the viscoelasticity image, we found that the viscoelasticities of each cell wall of the same cell were not the same. This is because the cellulose microfibrils in each cell wall lean in different directions. The angle between the leaning of the cellulose microfibril and the cantilever affects the viscoelasticity measurement.
基金supported by National Natural Science Foundation of China(Grant No. 21276199)Doctoral Program of Ministry of Education of China(Grant No. 20070247055)+2 种基金Program for Young Excellent Talents in Tongji University of China(Grant No. 2006KJ022)Shanghai Municipal Leading Academic Discipline Program of China(Grant No. B303)111 Project of China(Grant No. B08019)
文摘Water plays a critical role on the performance, stability and lifetime of proton exchange membrane fuel cells(PEMFCs). The addition of poly tetrafluoroethylene(PTFE) to the gas diffusion layer, especially, the cathode side, would optimize the transportation of water, electron and gas and thus improve the performance of the fuel cell. But until now, the studies about directly applying the PTFE to the catalyst layer are rarely reported. In this paper, the membrane electrode is fabricated by using directly coating catalyst to the membrane method(CCM) and applying PTFE directly to the cathode electrode catalyst layer. The performance of the single cell is determined by polarization curves and durability tests. Electrochemical impedance spectroscopy(EIS) and scanning electron microscopy(SEM) techniques are used to characterize the electrochemical properties of PEMFC. Also the performance of a 10-cells stack is detected. Combining the performance and the physical-chemistry characterization of PEMFC shows that addition of appropriate content of PTFE to the electrode enhances the performance of the fuel cell, which may be due to the improved water management. Addition of appropriate content of PTFE enhances the interaction between the membrane and the catalyst layer, and bigger pores and highly textured structure form in the MEA, which favors the oxygen mass transfer and protons transfer in the fuel cell. While superfluous addition of PTFE covers the surface of catalysts and hindered the contact of catalyst with Nation, which leads to the reduction of electrochemical active area and the decay of the fuel cell performance. The proposed research would optimize the water management of the fuel cell and thus improve the performance of the fuel cell.
基金the National Natural Science Foundation of China,№3904005"Hundred-Person plan"of Chinese Academy of Sciences,(№10989902)
文摘INTRODUCTIONThe endoplasmic reticulum(ER)consists of a complexsystem of tubules,lamellae,and flattened vesicles,andhas a variety of morphologies in different cells.It isbelieved to play a central role in the biosynthesis ofcholesterol,phospholipids, steroids, prostaglandins,
文摘BACKGROUND: Surgeons are always concerned about the localization of pancreatic functioning islet cell tumor. If the tumor is accurately localized before operation, resection of the pancreatic body and tail without intention can be avoided. The purpose of this study was to evaluate spiral CT localization of pancreatic functioning islet cell tumors and CT techniques. METHODS: CT manifestations in 6 patients with clinically and pathologically proved pancreatic functioning islet cell tumors ware analyzed retrospectively. RESULTS: In 4 patients with insulinomas and 2 patients with glucagonomas, 5 were localized accurately by CT be- fore surgery and 1 was detected retrospectively. The en- hancement of tumors was greater than that of normal pan- creas in arterial phase and pancreatic parenchymal phase. Four patients showed mild high-density and 2, iso-density in the portal venous phase. CONCLUSION: Spiral CT multi-phase enhanced scan with 1.5 ml/kg contrast agent and 2-5 mm slice width can loca- lize functioning islet cell tumors accurately.
基金Supported by the National Science Foundation of Hebei Province,No. 302489
文摘AIM: To investigate the effects of anti-fibrosis I herbal compound on intracellular Ca2+ in activated hepatic stellate cell (HSC) and to try to survey its molecular mechanism in treatment and prevention of hepatic fibrosis and portal hypertension.METHODS: The activated HSC line was plated on small glass cover slips in 24 wells culture dishes at a density of 5x106/mL, and incubated in RPMI-1640 media for 24 h.After the cells were loaded with Fluo-3/AM, intracellular Ca2+ was measured with laser scanning confocal microscopy (LSCM). The dynamic changes of intracellular Ca2+,stimulated by carbon tetrachloride, TGF-β1 antibody and the drug serum of anti-fibrosis I herbal compound and under orthogonal design were determined by LSCM. The effect of anti-fibrosis I herbal compound on intracellular Ca2+ was observed before and after the addition of TGF-β1antibody.RESULTS: The intracellular Ca2+ were significantly different in different dosage of carbon tetrachloride anti-fibrosis Iformula drug serum, TGF-β1 antibody and different turn of these substance, but their interval time between CCl4and TGF-β1 antibody, CCl4 and anti-fibrosis I drug serum had no influence on intracellular Ca2+. The result showed intracellular Ca2+ wasn't significantly different between rat serum without anti-fibrosis I and untreated group.After carbon tetrachloride stimulation, intracellular Ca2+ of activated HSC increased significantly when the dosage of CCl4 from 5 to 15 mmol/L, however, decreased significantly after stimulation by 5-20 μg/mL TGF-β1antibody or 5-20 mL/L drug serum. Moreover, before and after the addition of TGF-β1 antibody, intracellular Ca2+was significantly different. These results suggested that the molecular mechanism was independent of blocking TGF-β1 effects.CONCLUSION: Anti-fibrosis I herbal compound may treat hepatic fibrosis and decrease portal hypertension by inhibiting activated HSC contractility through decrease of intracellular Ca2+.
基金Supported by the National Natural Science Foundation of China, No. 30400591 the Heilongjiang Province Natural Science Foundation, No. D2004-13, D200505 Harbin City Young Scientist Foundation, No. 2004AFQXJ035
基金This work is partially supported by the Special Funding for Basic Research, Ministry of Education, Science, Sports and Culture, Japan, to K. K.
文摘We succeeded in performing of hybrid Scanning Probe Microscopy (hybrid-SPM) in which mechanical-SPM andfluorescence microscopy are combined. This technique is able to measure simultaneously mechanical properties anddistribution of cytoskeletons of living cells by using green fluorescent protein. We measured evolution of both local elasticityand distributions of actin stress fibers in an identical fibroblast living in physiological conditions. The SPM experimentsrevealed that stiffer lines develop in living cells, which correspond to actin stress fibers. The elasticity of the actin stressfibers is as high as 100 kPa. We discuss mechanical effects on the development of actin filament networks.