1.Risk factors and treatment experience of Pneumocystic carinii pneumonia after liver transplantation
Zixi LIU ; Jiqiao ZHU ; Xianliang LI ; Wenli XU ; Han LI ; Yanan JIA ; Qiang HE
Chinese Journal of Organ Transplantation 2021;42(4):214-218
Objective:To explore the risk factors of Pneumocystis carinii pneumonia (PCP) after orthotopic liver transplantation (OLT), and optimize the treatment strategy. Methods:From May 2015 to March 2019, patients undergoing OLT and suffering from postoperative PCP were selected into PCP group ( n=8). Using the propensity score matching method, controls without postoperative PCP were selected from concurrent OLT patients at a ratio of 1: 4 ( n=32). Clinical data were collected and counted for analyzing the risk factors of PCP post-OLT. Results:During this period, 385 cases of OLT were performed. The incidence of PCP was 2.1% (8/385). PCP group were all males with an average age of (52.63±12.99)(27-69) years. PCP has an average onset time of (19.88±13.22)(9-50) weeks post-OLT. There were benign liver disease ( n=2) and malignant liver tumor ( n=6). All operative approaches were modified camel OLT. Univariate analysis revealed significant differences in rejection, peripheral blood lymphocyte count and percentage of peripheral blood lymphocyte after OLT ( P<0.05) and no significant differences existed in other factors ( P>0.05). Logistic regression analysis indicated that a lower count of peripheral blood lymphocyte post-OLT was an independent risk factor for postoperative PCP. Conclusions:A lower count of peripheral blood lymphocyte post-OLT elevates the risk of PCP. For high-risk patients, prophylaxis with TMP-SMX (trimethoprim-sulfamethoxazole) may effectively lower the incidence of PCP post-OLT.
2.Clinical and genetic characteristics of patients with KCNV2-associated cone dystrophy
Tian ZHU ; Hui LI ; Lei WANG ; Xing WEI ; Shijing WU ; Zixi SUN ; Ruifang SUI
Chinese Journal of Experimental Ophthalmology 2020;38(4):312-318
Objective:To access the genetic defects and clinical characteristics of patients with KCNV2-associated cone dystrophy. Methods:Three pedigrees with KCNV2-associated cone dystrophy were recruited in Peking Union Medical College Hospital from August 2017 to December 2019.Peripheral blood from each patient and their parents was collected, and genomic DNA was extracted.Targeted exome capture plus next-generation sequencing (NGS) was used to detect the candidate variants.Suspected causative variants were validated by Sanger sequencing and segregation analysis.Comprehensive ocular examinations were performed, including vision acuity, colour vision, fundus photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), visual field and electroretinogram (ERG). This study was approved by the Institutional Review Board of Peking Union Medical College Hospital and adhered to the tenets of the Declaration of Helsinki.Written informed consent was obtained from each patient prior to any medical examination. Results:Three probands from three unrelated Chinese families were confirmed carrying biallelic KCNV2 disease-causing variants.Two patients harbored compound heterozygous variants and one patient with history of consanguinity was identified carrying homozygous variant.Five novel variants in the KCNV2 gene were identified, including p. T121M, p.R244C, p.C199Y, p.M250R and p. L171Pfs*201.All patients enrolled in this study were male with age of 25, 16 and 2 years old, respectively.Three affected individuals complained of vision loss and photophobia and two patients demonstrated reduced color perception and nystagmus.Macular discoloration (bull's eye maculopathy or gold foil macular reflex) was observed in fundus photographs.Macular hypofluorescence was illustrated in FAF imaging, which accompanying a broad hyperfluorescent ring surrounding the central atrophy or not.Macular thinning with loss of the inner segment ellipsoid zone was noted in OCT images, and the disruption was more profound in older patients.Central scotoma with or without peripheral visual field defects was observed in perimetry.Severe cone function loss and variable scotopic rod impairment were demonstrated in ERG, whereas a broad a-wave trough response to scotopic bright flash stimulation was noted. Conclusions:Patients with KCNV2-associated cone dystrophy show a characteristic ERG manifestation.ERG results and KCNV2 variants in Chinese patients differ from those in foreigners.
3.Experience in perioperative management of liver transplantation in hepatic coma patients
Huanye LIU ; Jiantao KOU ; Jun MA ; Jiqiao ZHU ; Long YANG ; Zixi LIU ; Xianliang LI ; Qiang HE
Organ Transplantation 2019;10(3):323-
Objective To analyse the clinical efficacy of liver transplantation and summarize the clinical experience of perioperative management in patients with hepatic coma. Methods Clinical data of 22 patients with hepatic coma undergoing liver transplantation were retrospectively analyzed. The perioperative conditions of the recipients were observed, including operation time, warm/cold ischemia time of donor liver, intraoperative anhepatic phase of the recipients, intraoperative blood loss, intraoperative blood transfusion, early postoperative blood drug concentration and incidence of postoperative complications. The survival situation of the recipients and the influencing factors of clinical prognosis were analyzed. Results The operation time of 22 recipients was 8 (6-12) h, the warm ischemia time of donor liver was 4 (2-6) min, the cold ischemia time was 7 (5-10) h, intraoperative anhepatic phase of recipients was 80 (55-120) min, intraoperative blood loss was 1 139 (400-4 000) mL and intraoperative blood transfusion was 1 440 (0-3 600) mL.The blood concentration of tacrolimus (FK506) fluctuated between 6 and 11 ng/mL at postoperative one week. Six recipients died after liver transplantation including 1 case of primary graft liver failure, 2 cases of severe infection, 1 case of severe cerebral edema caused by cerebral hemorrhage and 2 cases of multiple organ failure. The postoperative 1 month and 1 year survival rates of hepatic coma recipients were 82% and 77%. Conclusions Liver transplantation can significantly improve the survival rate of patients with hepatic coma. Preoperative decreasing blood ammonia, controlling postoperative infection, improving renal function and formulating precise individualized immunosuppression therapy according to immune status play a pivotal role in enhancing the survival rate.
4.The role of SnRK2 in the response to stress, the growth and development of plants.
Zixi LIU ; Yaxin ZHU ; Guoqiang WU ; Ming WEI
Chinese Journal of Biotechnology 2022;38(1):89-103
Sucrose non-fermenting-1-related protein kinase 2 (SnRK2) is a specific Ser/Thr protein kinase in plants. SnRK2 can regulate the expression of downstream genes or transcription factors through phosphorylation of substrates to achieve stress resistance regulation in different tissue parts, and make plants adapt to adverse environment. SnRK2 has a small number of members and a molecular weight of about 40 kDa, and contains a conserved N-terminal kinase domain and a divergent C-terminal regulatory domain, which plays an important role in the expression of enzyme. This review summarized the recent research progresses on the discovery, structure, and classification of SnRK2, and its function in response to various stresses and in regulating growth and development, followed by prospecting the future research direction of SnRK2. This review may provide a reference for genetic improvement of crop stress resistance.
Abscisic Acid
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Arabidopsis Proteins/genetics*
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Gene Expression Regulation, Plant
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Growth and Development
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Plants/genetics*
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Protein Kinases
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Protein Serine-Threonine Kinases/genetics*
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Stress, Physiological/genetics*
5.Clinical and genetic features of a Chinese family with ATF6-associated achromatopsia
Tian ZHU ; Hui LI ; Xing WEI ; Shijing WU ; Zixi SUN ; Ruifang SUI
Chinese Journal of Experimental Ophthalmology 2022;40(10):948-954
Objective:To identify the clinical characteristics and pathogenic gene of a Chinese Han family with achromatopsia (ACHM).Methods:The method of pedigree investigation was adopted.A Chinese Han ACHM family was recruited in Peking Union Medical College Hospital form July 2010 to July 2019, including 5 members of 2 generations.There were 2 patients and 3 phenotypically normal individuals.The medical history was collected and comprehensive ophthalmic examinations were performed, including visual acuity, colour vision, color fundus photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), visual field and electroretinogram (ERG).Genomic DNA was extracted from peripheral blood sample from the patients and family members.Pathogenic variant was screened by whole exome sequencing (WES) and verified by Sanger sequencing and co-segregation analysis.The variant was annotated with the 1000 Genomes, Human Gene Mutation Database (HGMD), ExAC, ClinVar and OMIM databases to detect the single nucleotide polymorphism and whether it had been reported previously.The pathogenicity of the variant was evaluated according to the standards and guidelines of the American College of Medical Genetics and Genomics (ACMG).This study adhered to the Declaration of Helsinki.The study protocol was approved by the Institutional Review Board of Peking Union Medical College Hospital (No.JS-2059).Written informed consent was obtained from the guardians of juvenile patients.Results:There was consanguinity between the proband's parents and this family was consistent with autosomal recessive inheritance.Both male patients presented the reduction of visual acuity accompanied with photophobia and color blindness since childhood.Barely visible foveal light reflex in fundus images, hypofluorescence of foveal areas in FAF images, foveal defect with disruption of ellipsoid zone and interdigitation zone in OCT images were found in both patients.Central scotoma with or without peripheral visual field defects was detected.Generally normal scotopic 0.01, 3.0 and 10.0 responses, decreased oscillatory potentials amplitudes, no photopic 3.0 and 30 Hz flicker responses were observed.No sign of progression was found during the 9-year follow-up.It was confirmed that both patients carried a novel homozygous disease-causing variant c. 947insA (p.Asn316Lysfs*46) in ATF6 gene.Their mother had the heterozygous variant.The unaffected brother did not carry the variant.This family was consistent with co-segregation.This variant was labeled as pathogenic according to the ACMG standards and guidelines. Conclusions:A novel variant c.947insA (p.Asn316Lysfs*46) in ATF6 gene is the pathogenic variant of this achromatopsia family.This is the first time that this variant has been reported.
6.Application of Mingdao immune score system for evaluating the immune status of liver transplant recipients
Jiantao KOU ; Xianliang LI ; Jiqiao ZHU ; Zixi LIU ; Chun BAI ; Long YANG ; Han LI ; Yanan JIA ; Jun MA ; Qiang HE
Chinese Journal of Organ Transplantation 2020;41(6):362-366
Objective:We proposed a Mingdao immune score system(MISS)to evaluate recipient's immune status after liver transplantation.Methods:From January 2017 to June 2019, retrospective analysis was conducted for 89 recipients of liver transplantation. Age/gender-matched 385 healthy controls(HC)were selected. The percentages of 30 lymphocyte subgroups of patients and HC were measured by flow cytometry. The score of each individual was calculated with our proposed MISS method. And drug concentrations and relevant clinical data were collected.Results:The normal MISS value of a healthy person was 0 score according to our criterion. In this study, the value of MISS for HC was distributed in a nearly normal fashion(-0.73±4.02). When the data from patients at different timepoints were compared, the MISS value started with -1.21±7.42 pre-operation, then declined sharply down to -8.95±8.05 at 1 month and jumped to -4.50±7.80 at 3 months. Afterward it stabilized at -4.18±7.83 between 3~12 months post-operation and finally reached -2.00±5.51 at 1 year ( P<0.05). Patients with acute rejection had higher MISS values than those without acute rejection, ( P<0.05). No significant correlation existed between blood drug concentrations and MISS values ( P>0.05). Conclusions:Our proposed MISS method may reflect the whole immune status. It is useful to manage the application of immunosuppressants in conjunctions with blood drug concentrations and liver graft function.
7.Radiation shielding for the intraoperative radiotherapy using low energy X-rays
Daguang ZHANG ; Zixi ZHU ; Jiana SUN ; Yuan TIAN ; Wei WANG
Chinese Journal of Radiological Medicine and Protection 2022;42(8):629-635
Objective:To assess the shielding requirements of low energy X-ray intraoperative radiotherapy room under the domestic and foreign standards and guidelines, to measure the sured transmission factors for a range of shielding materials, the ambient dose equivalent rate around concerned positions and the shielding effect of protective devices, so as to provide references for shielding design of such radiotherapy units and applications of radiological protection devices.Methods:The required shielding thicknesses for a treatment room with INTRABEAM intraoperative radiotherapy system were calculated under the Chinese national standard GBZ 121, IPEM report No. 75 and NCRP report No. 151, respectively. The transmission factors for a range of shielding materials including solid water slab, shielding sheet and shielding apron were measured. Moreover, the ambient dose equivalent rates were measured under the simulated working conditions and the shielding effectiveness of a lead screen was evaluated.Results:The required lead thicknesses calculated under different standards and guidelines were less than 0.6 mm for all the concerned points, with the differences at sub-millimeter level. The low energy X-rays generated by this equipment attenuated rapidly in the shielding materials. The measured transmission factors of 0.05 mm lead equivalent shielding sheet and 0.25 mm lead equivalent shielding apron were 0.068 and 0.003 8, respectively. When the radiation was delivered using spherical applicator without any attenuation, the ambient dose equivalent rates at 1 m and 2 m from the X-ray source were 10.7 and 2.6 mSv/h, respectively. The corresponding measurement values decreased to 3.8 and 0.9 μSv/h, respectively, when the spherical applicator was inserted into a small water tank. Meanwhile, the ambient dose equivalent rate at 2 m was reduced to the background level when using protective screen.Conclusions:The shielding requirements for a low energy X-ray intraoperative radiotherapy facility are minimal, with low effective energy of X-rays generated by this equipment, but the dose rate close to the unshielded radiation source is high. The shielding scheme of treatment room should be optimized in design and the protective device should be used in a reasonable way.