1.Histopathological observation after radial optic neurotomy in human eyes
Xiaowei TONG ; Peiquan ZHAO ; Rongjia CHEN
Chinese Journal of Ocular Fundus Diseases 1999;0(02):-
Objective To explore the histopathological changes of the radial optic neurotomy (RON) in human eyes, and to establish the theoretical foundation for the effective RON. Methods Ten patients with unaffected eyeball or optic disc who had undergone ophthalmectomy (7 patients) or orbital exenteration (3 patients) because of intraocular or orbital tumor were gathered. A double-incision in pars plana was performed. One was inserted into illuminating fiber, and another was inserted into a standard microvitreoretinal (MVR) blade (unbent MVR blade in 4 patients and bent ones in 6; radial incision on nasal side of the optic disc in 4 patients and on both nasal and temporal side in 6). The histopathological examination was performed to observe the location and depth of the incision. Results Eleven incisions were found in 8 out of 10 patients, of which surgical spaces can be observed clearly. Three incisions were obliquely inserted into the optic nerves, 5 sieve plate lateral incisions had the surgical intervals connected with the subarachnoid spaces, and 3 incisions caused obvious damage of retinal ganglion cell axons due to the position close to the center. Nine incisions approached to the retrolaminal level, and the other 2 reached the laminal and prelaminal level respectively. Injured retina beside the optic disc in 1 incision was found. Central retinal vessels were not damaged. Conclusions An optimal incision may be in the edge of the lamina cribrosa, whose depth should be in the level of lamina cribrosa and retrolamina, with surgical intervals connected with the subarachnoid spaces.
2.In-vitro Sensitivity of Plasmodium falciparum to the Components of Dihydroartemisinin Compounds in Dongfang City of Hainan Province
Lailai LIU ; Peiquan CHEN ; Fengzhen OU ; Chongwei FU
Journal of Guangzhou University of Traditional Chinese Medicine 2004;0(05):-
[Objective] To examine the sensitivity of P. falciparum to the components of dihydroartemisinin (DHA) and piperaquine (PQ) in Dihydroartemisinin Compounds. [Methods] WHO (World Health Organization) standard micro test and in-vitro test were used. [Results] Survey in the year of 2001 for 61 cases and in 2004 for 28 cases showed that the DHA-resistant rate of P. falciparum in all cases was zero with inhibitory concentration of 50% (IC50) being 6.84 nmol/L and 5.67 nmol/L, and the mean concentration for complete inhibition of schizont formation was 35 nmol/L and 39 nmol/L, respectively. Survey in the year of 2001 for 75 cases and in 2004 for 29 cases showed that PQ-resistant rate of P. falciparum was 22.67% and 17.24% with IC50 being 274 nmol/L and 317 nmol/L, and the mean concentration for complete inhibition of schizont formation was 1 220 nmol/L and 1 269 nmol/L, respectively. [Conclusion] No DHA -resistance exists and PQ-resistance decreases for the treatment of P. falciparum in Dongfang city of Hainan province.
3.Gene Typing of Merozoite Surface Protein 1 of Plasmodium falciparum isolates from Hainan Province *
Gangfeng JIANG ; Jiadong HONG ; Peiquan CHEN ; Shanqing WANG ; Feng MENG ;
Chinese Journal of Parasitology and Parasitic Diseases 1987;0(01):-
Objective To identify the genotype of merozoite surface protein 1 (MSP1) of Plasmodium falciparum isolates from Hainan Province. Methods Nested PCR was applied to amplify the MSP1 of Blocks 2 and 3 Plasmodium falciparum isolates from Hainan Province. Two allelic family representitive gene fragments were sequenced.Results From 36 out of 39 blood samples from Plasmodium falciparum patients, 44 gene fragments of blocks 2 and 3 of the MSP1 were amplified, of which the MAD20 type allele was dominant(75%). followed by K1 type allele. No RO33 type allele was found. The mixed infection rate of the two different allelic type was 19 4%. Sequence analysis showed that the sequences of MAD20 and K1 type isolates from Hainan Province were highly homologous to that of the MAD20 and K1 allelic prototypes.Conclusion Two principal allelic types of MSP1 gene, MAD20 and K1 type, exist in malaria endemic areas in Hainan Province, the MAD20 type being the dominant.
4.Determination of bulleyacinitine A in mouse plasma by liquid chromatography tandem mass spectrometry
Weigen LU ; Ping XIANG ; Tingting CHEN ; Peiquan WANG ; Dequan REN
Chinese Traditional Patent Medicine 1992;0(10):-
AIM:To develop the method for analyzing bulleyacinitine A in plasm from mice through the treatment of subcutaneous injection of bulleyacinitine A by liquid chromatography tandem mass spectrometry(LC-MS/MS).METHODS:50 ?L mouse plasma sample added zolpidem as internal standard and pH 9.2 buffer solution was extracted with ethylether,followed by liquid chromatography and mass spectrometric detection.The mobile phase was consisted of methanol-buffer solution(85∶15)(buffer solution consisted of 20 mmol/L ammonium acetate and 0.1% formic solution).The flow rate was 300 ?L per minute.The separation column was C_ 18 column.The electrospray ionization tandem mass spectrometry and the multiple reaction monitoring mode were applied to detecting the bulleyacinitine A in plasma.RESULTS:The assay was linear from 0.1 to 1 000 ng/mL.The recovery rate was more than 80%.CONCLUSION:The method could be used to detect bulleyacinitine A level in mouse plasma,which offers advantages of sensitiveness,specificity and simpleness.
5.Recent advances in foveal development after treatment for retinopathy of prematurity
Shuangshuang CHEN ; Qi ZHANG ; Jianing REN ; Jie PENG ; Peiquan ZHAO
Chinese Journal of Ocular Fundus Diseases 2021;37(5):394-398
Retinopathy of prematurity (ROP) is a proliferative vascular retinal disease. Cryotherapy, laser photocoagulation, intravitreal injection of anti-vascular endothelial growth factor, scleral buckling surgery and vitrectomy are the main treatments. Treated with cryotherapy or laser photocoagulation or intravitreal injection of anti-vascular endothelial growth factor, patients with a history of ROP have thicker foveas, and the morphology of the fovea and the development of the retinal vessels in the macular area are affected, resulting in abnormal vision development. However, the specific mechanisms by which different treatments of ROP affecting the development of the macula are not yet clear. It still need further study with large samples to verify and explore, whether changes in the levels of intraocular vascular endothelial growth factor changing the process of normal macular development and how the abnormal development of the macula affects visual function.
6.Comparative Studies on Effects of Dihydroartemisinin and Quinine on Plasmodium Falciparum Gametocytes at Early Stage
Peiquan CHEN ; Huaxiang JIAN ; Linchun FU ; Lisheng FAN ; Bingxi WANG ; Guoqia LI
Journal of Guangzhou University of Traditional Chinese Medicine 2001;0(01):-
Objective To study the effects of dihydroartemisinin and quinine on plasmodium falciparum gametocytes at early stage. Methods Eleven patients with falciparum malaria who had plasmodium falciparum gametocytes at early stage(PFGe) in bone marrow but no matured plasmodium falciparum gametocytes(PFGm) in bone marrow and peripheral blood were allocated to two groups.Group A(n=6) were administered orally with dihydroartemisinin at a total dosage of 480mg for 7 days and Group B(n=5) with quinine sulfate at a total dosage of 10?500 mg for 7 days.The number of gametocytes in bone marrow and peripheral blood was examined at regular time. Results PFGe in bone marrow disappeared in Group A on 10 th day after the first administration while existed in all the cases of Group B on 10 th day and still in 2 cases on 14 th day.The clearance time for peripheral PFGe was 4.8?0.9 days in Group A and 22.0?5.8 days in Group B. Conclusion Dihydroartemisinin can clear PFGe but quinine shows no this action.
7.INFLUENCE OF ARTESUNATE ON INFECTIVITY OF GAMETOCYTES OF PLASMODIUM FALCIPARUM
Peiquan CHEN ; Guoqiao LI ; Huaxiang JIAN ; Yuerong ZHANG ; Linchun FU ; Jinying ZHENG ; Lisheng FAN ; Shidu RUAN ;
Traditional Chinese Drug Research & Clinical Pharmacology 1993;0(03):-
A study was carried out in south of Vietnam 15 Patients with Plasmodium falciparum gametocytes and asexual parasites were distributed into groups A, B and C. Artesunate was given orally at a total dose of 600 mg for 5 days in group A, 200 mg for 2 days in group B and intravenously at a total dose of 360 mg for 5 days in group C respectively. Gametocytes count was done before medication and daily after medication. Meanwhile, Anopheles dirus as a vector was employed to study the infectivity of gametocyte, The result showed that the mean gametocyte clearance time in three groups were respectively 15.4?5.0, 20.6?4.8 and 20.3?4.0 days. The mosquitoes were not infected from the blood in 2, 5 and 5 of 5 patients respectively on days 7, 14 and 21 in group A; 1 and 5 of 5 patients on day 14 and 21 in group B; 2 of 5 patients and 3 of 3 patients on days 14 and 21 in group C. It indicates that artesunate has remarkable effect on Plasmodium falciparum gametocytemia and its infectivity to mosquitoes.
8.One-year Report on the Fast Elimination of Malaria by Source Eradication (FEMSE) Project in Moheli Island of Comoros
Guoqiao LI ; Jianping SONG ; Changsheng DENG ; Moussa Mohamed ; Ahamada MSA Mliva ; Fatihou Oithik ; Peiquan CHEN ; Bo TAN ;
Journal of Guangzhou University of Traditional Chinese Medicine 2010;27(1):90-98
Objective To investigate the therapeutic effect of the method of Fast Elimination of Malaria by Source Eradication (FEMSE) in Moheli island of Comoros. Methods Based on the FEMSE project, parasite positive cases were given a standard treatment course of ARTEQUICK (artemisinin plus piperaquine) plus primaquine: two tablets for adults at 0 hour and two tablets at 24 hours, a total of 4 tablets during one treatment course. One time of Mass Drug Administration (MDA) was for the children with parasite carrier rate less than 10%. Two times of MDA was for the children with parasite carrier rate more than 10%, and the interval between the two MDA was 42 days. Coverage rate for MDA and population carrier rate were observed. Results The number of people taking the first MDA of Artequick-Primaquine was 32,519 (the whole population registered at the same time being 37,243, 367 infants under 6 months old not involved), and the coverage rate for MDA was 88.2%. The population involved in the second MDA was 35,370 (the whole population registered at the same time being 37,112, 335 infants under 6 months old not involved), and the coverage rate for MDA was 96. 2%. Parasite carrier rate was 22.95% (281/ 1,224) before MDA, 1.41% (28/1, 987) two months after MDA and 0. 33% (8/2,458) four months after MDA, with a decrease of 98.56% . Conclusion The decrease of parasite carrier rate from 22. 95% to 0. 33% before and after MDA indicates that MDA of Artequick-Primaquine based on FEMSE can decrease the parasite carrier rate in a short time, without any obvious side effects. Further decrease of parasite carrier rate and incidence will be achieved if the measures for clearing malaria are fully implementated during the consolidation phase.
9.Prediction model for the risk of postoperative death in patients with acute type A aortic dissection
Peiquan LI ; Shaopeng ZHANG ; Yunpeng BAI ; Tongyun CHEN ; Feng ZHAO ; Nan JIANG ; Qingliang CHEN
Chinese Journal of Thoracic and Cardiovascular Surgery 2024;40(2):72-78
Objective:Using different machine learning methods to construct and screen the best prediction model for predicting the risk of death within 30 days after surgery in patients with acute type A aortic dissection.Methods:Five hundred and twenty-one patients with acute type A aortic dissection who underwent surgery between 2015 and 2022 were included, after collecting their perioperative date and screening them, 329 patients were retained. two different groups of predictor variables were generated by using Lasso regression and principal component analysis, after that, logistic regression, support vector machine algorithm, random forest algorithm, gradient boosting algorithm, and super learning algorithm were used to develop prediction models for the risk of death within 30 days after surgery. Finally, we compare the models and select the best one. Results:The AUC values for all models rangrd from 0.791-0.959. The model using Lasso regression to determine the predictor variables and built by the super learning algorithm had the best prediction with an AUC value of 0.959. Conclusion:The super learning algorithm better than other algorithms in predicting death within 30 days after acute type A aortic dissection.
10.Surgical treatment and current advances of persistent fetal vasculature syndrome
Jianing REN ; Jie PENG ; Shuangshuang CHEN ; Yihua ZOU ; Peiquan ZHAO
Chinese Journal of Ocular Fundus Diseases 2022;38(2):163-167
Persistent fetal vasculature syndrome (PFVS) is a rare congenital vitreous dysplasia, which is classified as anterior, posterior and combined types according to the location of the vascular abnormalities. The clinical manifestations of PFVS are diverse, and early surgical intervention is very important. The main objective of surgical treatment is to remove the anterior and posterior traction between fibrovascular membranes and retina as well as lens, and to reconstruct clear visual axis. Surgical treatments include pupilloplasty, lensectomy with or without intraocular lens implantation and vitrectomy via limbal or scleral approach. For new technologies, the applications of ophthalmic viscosurgical device and femtosecond lasers have desirable results . In addition to focusing on improving the success rate of surgery, it is also necessary to systematically and comprehensively assess the overall preoperative condition and postoperative visual function of the patients. PFVS eyes have limited improvement in postoperative vision, which is related to the extent of lesion involvement and the occurrence of complications. Eyes with macular dysplasia and tractional retinal detachment, as well as elongated ciliary process, have a poor prognosis of vision after surgery. How to improve postoperative vision in the eye affecting the posterior segment of the eye with PFVS from the microscopic anatomical relationship between the fibrous vascular pedicle and the retina is worth further study. On the other hand, reducing surgical trauma and optimizing surgical procedures in order to improve postoperative visual acuity and reduce postoperative complications are also the key research directions of future PFVS treatments.