1.Application of iterative algorithm in paranasal sinus MSCT
Chinese Journal of Radiological Medicine and Protection 2014;34(5):390-393
Objective To study the effect of iterative algorithm (iDose algorithm) on image quality and radiation dose in paranasal sinus MSCT.Methods A proper cadaveric head based on the average CNR (contrast noise ratio) of paranasal sinus images in 53 patients was applied.The cadaveric head was scanned with different parameters of kV and effective mAs.The images were reconstructed with filtered back projection and iterative algorithm (iDose 1-7) respectively.The subjective and objective evaluations were performed for all the images and the optimal parameter combination was found out.Results The CNR of coronal images was slightly higher than that of axial images (t =-6.86,P <0.05).The image CNR of protocol (120 kV,100 mAs/slice and iDose5) was close to that of conventional protocol.The protocol of 100 kV,60 mAs/slice and iDose4 offered the images adaptable for diagnosis of inflammation.The protocol of 100 kV,80 mAs/slice and iDose4 offered the images adaptable for diagnosis of inflammation and fracture,and the radiation dose were reduced by 82% and 75%,respectively.Conclusions Using the iDose algorithm could help to offer diagnostic images for inflammation and fracture and reduce the radiation dose in the paranasal sinus MSCT.
2.Sintering character of nanocrystal calcium-deficient apatite
Yantao ZHAO ; Dagang GUO ; Yumei ZHANG
Journal of Practical Stomatology 1996;0(02):-
Objective:To study the sintering character of calcium-deficient apatite.Methods:Calcium-deficient apatite synthesised by wet chemical method was sintered at different temperature and then its chemical composition, phase structure and morphology were examined by FT-IR spectroscopy, X-ray diffraction (XRD) and field emission scanning microscopy (FESEM) respectively.Results:When the heating temperature is below 500 ℃, apatite crystal kept a stable size with a diameter of 12-26 nm and a length of 30-66 nm. After sintered at 600 ℃ for 2 h, apatite crystal were with a diameter of 25-40 nm and a length of 75-100 nm. Around 800 ℃ for 2 h, apatite was decomposed into Ca_3(PO_4)_2.The crystal size of the Ca_3(PO_4)_2 surpassed 200 nm in diameter and length. NH_4+ ion could be removed at temperature beyond 300 ℃.Conclusion: Calcium-deficient apatite has it's specific sintering character.
3.Investigation on effect of dual-source CT scanning patterns on radiation dose and image quality of head and neck
Yantao NIU ; Yongxian ZHANG ; Senlin GUO ; Binbin YU
Chinese Journal of Radiological Medicine and Protection 2016;36(12):943-946
Objective To study the impact on the radiation dose,organ doses of eye lens and thyroid and image quality with different scanning modes in head and neck CT scan.Methods The simulation phantom of head and neck was scanned by using fixed scanning condition (120 kV and 200 mAs),as well as the combinations of automatic tube current modulation (CARE Dose 4D),automatic tube voltage modulation technique (CARE kV) and partial angle scanning mode (X-CARE) respectively.Six kinds of scanning modes were adopted,including 120 kV +200 mAs,120 kV + 200 mAs + X-CARE,CARE Dose 4D + 120 kV,CARE Dose 4D + 120 kV + X-CARE,CARE Dose 4D + CARE kV,CARE Dose 4D + CARE kV + X-CARE.Two thermolumineseece dosimeters (TLDs) were exposed at the skin surface positions of eye lens and thyroid,and the values measured with two TLDs were averaged.The CT dose index volume (CTDIvol) and dose length product (DLP) for every scan were recorded,and the contrast to noise ratio (CNR) in eye lens section and thyroid section were measured.Results The crgan doses of lens and thyroid were 19.8 and 26 mGy at 120 kV and 200 mAs,as well as 13.3 and 22.2 mGv at X-CARE mode.Compared with the manual selection of 120 kV,the combination of CARE kV and CARE Dose 4D made the values of CTDIvol drop from 13.1 to 10.1 mGy,the doses of eye lens and thyroid from 16.6 and 20.8 mGy to 23.7 and 19.9 mGy respectively,while the image quality reducedsignificantly.Compared with CARE Dose 4D + 120 kV,the organ doses of eye lens and thyroid were reduced from 20.8 and 23.7 mGy to 9.6 and 15.1 mGy for with additional X-CARE,while CTDIvol dropped from 13.1 to 9.3 mGy.When the combination of CARE Dose 4D + CARE kV + X-CARE was used,CTDIvol and organ doses were reduced to a minimum,when the CNRs of head and neck were also minimized.Conclusions The scanning mode CARE Dose 4D + 120 kV + X-CARE for head and CARE Dose 4D + CARE kV for neck can effectively reduce the radiation dose while keeping good image quality.When requirements for image quality are not high,CARE Dose 4D + CARE kV + X-CARE mode can be selected to reduce the radiation dose significantly.
4.Efficient transient expression to analyze miRNA targets in rice protoplasts.
Ping GUO ; Yao WU ; Jia LI ; Rongxiang FANG ; Yantao JIA
Chinese Journal of Biotechnology 2014;30(11):1751-1762
Compared with the transgenic approach, transient assays provide a convenient alternative to analyze gene expression. To analyze the relationship between miRNAs and their target genes, a rice protoplast system to detect target gene activity was established. The MIRNA and GFP-fused target sequence (or GFP-fused mutated sequence as a non-target control) were constructed into the same plasmid, and then delivered into rice protoplasts. The GFP expression level decreased significantly when the protoplasts were transfected with the plasmid containing GFP-fused target compared to that of the plasmid with non-target sequence either by fluorescence microscopy or qRT-PCR method. Two microRNA genes, osaMIR156 and osaMIR397, and their target sequences were used to prove the feasibility of the rice protoplast transient assay system. This method will facilitate large-scale screening of rice miRNA target in vivo, and may be suitable for functional analysis of miRNAs of other monocot plants that might share the evolutionarily conserved small RNA processing system with rice.
Gene Targeting
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Green Fluorescent Proteins
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genetics
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MicroRNAs
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genetics
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Oryza
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genetics
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Plasmids
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Protoplasts
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metabolism
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RNA, Plant
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genetics
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Transfection
5.Traditional Chinese Medicine Syndrome Differentiation of AIDS Patients on ARV Complicated with Anemia and Hyperlipidemia
Jun YUAN ; Zhen LI ; Yantao JIN ; Zhibin LIU ; Qiang LI ; Huijun GUO
World Science and Technology-Modernization of Traditional Chinese Medicine 2013;(3):555-559
This study was aimed to analyze four diagnostic methods of AIDS patients with HAART complicated with anemia and hyperlipidemia. Characteristics of traditional Chinese medicine (TCM) and common pathogenesis were discussed in this article. This study was supported by Key Project of the National Eleventh-Five Year Research Program of China. This study was conducted through the retrospective analysis. This analysis was made on the four diagnostic methods of AIDS patients with HAART treatment. The results showed that the most frequent symptoms of AIDS patients with anemia or hyperlipidemia are fatigue, facial abnormalities, taste abnormalities, forgetfulness, backache, weakness of back, loss of appetite, insomnia. And the frequent tongue and pulse are white tough coating, pale tongue and fine pulse. The most frequent symptoms of the anemia group are facial abnormalities, backache, dizziness, palpitations, shortness of breath, pale complexion, abnormal state of mind, abnormal sweating, tinnitus, cold hands and feet, spontaneous sweating, white tongue coating, tooth-printed tongue, thin tongue coating and weak pulse (P < 0.05). The most frequent symptom of hyperlipidemia are lassitude, weakness, loss of appetite, abdominal distension, moisture tongue, thick and greasy tongue coating, slippery pulse. It was concluded that syndromes of AIDS patients on ARV complicated with anemia and hyperlipidemia are mainly deficient pattern, which affects the spleen, heart, liver and kidney. The most frequent syndrome type with anemia patients is blood deficiency, which is followed by spleen-kidney deficiency syndrome, liver-kidney deficiency syndrome. The most frequent syndrome type with hyperlipidemia patients is spleen qi deficiency and kidney essence deficiency, which are closely related to the spleen and kidney.
6.Expression of GABAB1 receptors in spinal dorsal horn neurons in rats with diabetic neuropathic pain
Yantao LIU ; Xiuli WANG ; Qian WANG ; Rui DONG ; Jianghong MA ; Qiujun WANG ; Yuexian GUO
Chinese Journal of Anesthesiology 2010;30(10):1216-1219
Objective To investigate the role of GABAB1 receptors in spinal dorsal horn neurons in the development of diabetic neuropathic pain (DNP). Methods Sixty pathogen free male SD rats aged 4 weeks weighing 150-170 g were randomly divided into 2 groups ( n = 30 each): control group and DNP group. Diabetes mellitus was induced by single intraperitoneal injection of streptozotocin 50 mg/kg. Blood glucose levels and paw withdrawal threshold to mechanical stimuli were measured at 3, 5 and 7 weeks (T1, T2, T3 ) after IP STZ/NS ( n = 10 each). The animals were sacrificed after PWL measurement. The lumbar segment of the spinal cord was removed for determination of the expression of GABAB1 receptors by immuno-histochemistry, RT-PCR and Western blot analysis. Results The blood glucose levels were significantly higher while the PWT was significantly lower at T1,T2 and T3 in group DNP than in control group. The expression of GABAB1 receptor mRNA and protein in spinal dorsal horn was significantly lower at T2 and T3 in DNP group than in control group. Conclusion The expression of GABAb1 receptors is down-regulated in spinal dorsal horn neurons in rats with DNP.
7.Role of M3 muscarinic acetylcholine receptor in glycinergic neurotransmitter release in spinal lamina Ⅰneurons in rats
Rui DONG ; Xiuli WANG ; Yuexian GUO ; Yantao LIU ; Qiujun WANG ; Shuping HUO
Chinese Journal of Anesthesiology 2010;30(6):715-717
Objective To evaluate the role of M3 muscarinic acetylcholine receptor (M3 mAChR) in the release of glycinergic neurotransmitter by using oxotremorine-M (Oxo-M: a nonselective mAChR agonist) and 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP: a highly selective M3mAChR antagonist). Methods Twenty male 3-4 weeks old SD rats weighing 160-180 g after successful intrathecal catheterization were randomized into 2 groups (n = 10 each): normal saline group (group NS) and pertussis toxin (group PTX).Pertussis toxin 1.5 μg/10 μl was injected IT in group PTX, while in group NS normal saline 10 μl was injected IT instead. The animals were killed at day 7 after injection. The spinal cords were removed and sliced and placed in artificial CSF. Glycinergic spontaneous inhibitory postsynaptic currents (sIPSCs) were measured in spinal lamina Ⅱneurons using whole-cell voltage-clamp technique. Five minutes after sealing, Oxo-M (final concentration 3 μ mol/L) was added. Oxo-M was then completely washed out 3 min later and 4-DAMP (final concentration 25 nmol/L) was added after 5 min of stabilization. In the presence of 4-DAMP, Oxo-M (final concentration 3 μmol/L) was added again 3 min later. sIPSCs were recorded before addition of Oxo-M (T1), 3 min after addition of Oxo-M (T2), 3 min after addition of 4-DAMP (T3), 3 min after the second addition of Oxo-M (T4). Results Compared with the baseline value at T1 , Oxo-M significantly increased the frequency of glycinergic sIPSCs at T2without changing the amplitude at T2-4 in both groups. The frequency of sIPSCs was significantly lower at T4 than at T2 in both groups (P < 0.05 or 0.01). There was no significant difference in both frequency and amplitude of glycinergic sIPSCs between the two groups. Conclusion M3 mAChR plays a predominant role in the release of glycinergic transmitter in the spinal lamina Ⅱ neurons in rats.
8.Radiation dose reduction to the lens of eye with bismuth shielding in head and neck MSCT
Yantao NIU ; Yaoyao SONG ; Yongxian ZHANG ; Senlin GUO ; Zongrui ZHANG ; Tianliang KANG ; Yunfu LIU
Chinese Journal of Radiological Medicine and Protection 2015;35(2):149-152
Objective To explore the effects on image quality and dose reduction to the lens when using bismuth shielding in head and neck MSCT.Methods The standard phantom and the cadaveric head with none,1,2 and 3 layers of bismuth shielding were scanned with protocols of brain,temporal bone and paranasal sinuses using a 16-MDCT scanner.The organ dose to the lens in each scanning was measured with thermoluminescence dosimeters(TLD).The above scanning with sinus protocol was repeated with a sponge with thickness of 5,10,15 and 20 mm placed between the shielding and phantom/head.The CT attenuation of phantom with the distance of 2,4,6 and 8 cm to shielding were measured.The image quality was subjectively evaluated by 2 physicians.Results The organ doses of the lens with protocols of brain,temporal bone and sinuses were 24.31,27.60 and 20.01 mGy,respectively.The doses were decreased significantly when using bismuth shielding.With the increase of the shield gap,the degree of dose reduction was reduced,but the increasing degree of CT attenuation significantly reduced.Using 2-layer and 3-layer bismuth shield in brain and temporal bone CT scan,the radiation doses were reduced by 47.1% and 59.1%,respectively while maintaining the diagnostic image quality.Using 1-layer shield without gap and 2-layer shield with 1.5 cm gap in sinus CT,the radiation doses were reduced by 31.5% and 34.5%,respectively.Conclusions Reasonable usage of bismuth shielding can effectively reduce the radiation dose to the lens of eye in head and neck MSCT.
9.The influence of bismuth shielding on image quality and radiation dose to eye lens in sinus multi-detector CT
Yantao NIU ; Zongrui ZHANG ; Yongxian ZHANG ; Senlin GUO ; Tianliang KANG ; Yunfu LIU
Chinese Journal of Radiology 2014;48(4):324-327
Objective To explore the influence on image quality and the reduction of radiation dose to eye lens when using bismuth shielding in sinus MDCT.Methods The standard water phantom was scanned using clinical scanning protocols of sinus in 16-MDCT,and the images were acquired with none,1 layer,2 layers and 3 layers of bismuth shielding severally.Using the above protocol,the cadaveric head was scanned with no shield,1,2 and 3 layers of bismuth shielding material covered on both eyes,and the organ dose to eye lens in each scanning was measured with thermoluminescence dosimeter (TLD).The sponge with the thick of 0.5,1.0,1.5,2.0 cm was placed between the shielding material and the surface of subjects separately and the radiation doses to eye lens was measured with sinus scanning conditions in the same way.The CT values of phantom with the distances of 2.0,4.0,6.0 and 8.0 cm to shield material were measured.The influence of bismuth artifacts on anatomic structures was evaluated as well.Results The organ doses to the eye lens in the sinus clinical CT were 20.0 mGy.Doses decreased significantly to 13.7,10.9 and 9.4 mGy separately when using 3 types of bismuth shielding thickness.With different thicknesses of shielding material,the greater the shield gap,the smaller the degree of reduction of organ dose,but the increasment of CT value was significantly reduced.Using 1-layer shield no gap and 2-layer shield with 1.5 cm gap in sinus MDCT,the radiation doses were reduced to 13.7 and 13.1 mGy with the reduction rates of 31.5% and 34.5% respectively.Conclusion The reasonable bismuth shielding can effectively reduce the radiation dose to eye lens in sinus CT on the premise of ensuring image-diagnostic quality.
10.Clinical analysis of salvage surgery after noncurative endoscopic resection for early gastric cancer
Hong ZHOU ; Dongbing ZHAO ; Yantao TIAN ; Chunguang GUO ; Yingtai CHEN ; Guiqi WANG
Chinese Journal of General Surgery 2021;36(4):259-262
Objective:To evaluate salvage surgery in patients with early gastric cancer after noncurative endoscopic resection .Method:A total of 56 cases with early gastric cancer receiving salvage surgery after noncurative endoscopic resection were enrolled and the clinicopathological and follow-up information were analyzed to evaluate the necessity and safety of salvage surgery.Results:Among the 44(79%)patients with submucosal invasion, 38 (68%) were with SM2 (invasion submucosal invasion≥500 μm) according to the pathological results after endoscopic resection. 33 (59%)cases had positive margin. The rate of lymph node metastasis and positive residual tumor as found by salvage gastrectomy were 11% (6/56) and 25% (14/56) . In the multivariate analysis, deeper submucosal invasion resulted as independent risk factor for residual tumor( OR=1.001, 95% CI=1.000-1.002, P=0.036). Among the 12(21%)cases with postoperative complications, 3 (5%)underwent unplanned reoperations because of anastomotic or intra-abdominal bleeding. There was no difference in the number of retrieved lymph nodes and rate of postoperative complications between laparoscopic and open surgery(all P>0.05). Conclusion:For patients with the risk factors of lymph node metastasis after noncurative endoscopic resection, salvage surgery was necessary and laparoscopic approach was safe and feasible.