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Purpose: To compare the functional and clinical outcomes of knee joints in patients over a 10-year period following posterior cruciate ligament (PCL) reconstruction with single-bundle versus double-bundle., Methods: Patients who underwent PCL reconstruction were retrospectively analyzed. Based on the surgical approach, they were divided into the single-bundle reconstruction group and the double-bundle reconstruction group. Preoperative and postoperative Lysholm score, International Knee Documentation Committee (IKCD) score, and Tegner activity score were evaluated, and the stability of the joints was assessed using KT-2000 arthrometer. Radiographs were taken at the final follow-up to evaluate the progression of osteoarthritis., Results: A total of 61 patients were included in the analysis: 26 in the double-bundle group and 35 in the single-bundle group. Baseline data were comparable between the two groups (P > 0.05). There were no significant differences between the two groups in preoperative Lysholm, IKDC score, and Tegner activity score. Postoperatively, these scores were significantly higher at two and ten years follow-up (P < 0.05), with no significant difference between the groups (P > 0.05). There was no significant difference in side-to-side differences (SSD) at 30° and 90° of knee flexion preoperatively between the groups (P > 0.05). Postoperatively, SSD decreased significantly at the two year and ten year follow-up (P < 0.05), with no significant difference between the groups (P > 0.05). For osteoarthritis progression, there were four cases of Kellgren-Lawrence grade ≥ II in the single-bundle group and three cases in the double-bundle group, with no significant difference in the progression of osteoarthritis between the groups (P > 0.05)., Conclusion: Both single-bundle and double-bundle reconstructions for PCL result in good joint stability and mobility, with similar progression of osteoarthritis in long-term follow-up., Level of Evidence: Level III., Competing Interests: Declarations. Ethics approval and consent to participate: This study was approved by the Medical Ethics Committee of Wangjing Hospital of China Academy of Chinese Medical Sciences and all patients voluntarily signed an informed consent form. Financial support and sponsorship: None. Conflicts of interest: None., (© 2024. The Author(s) under exclusive licence to SICOT aisbl.)

A self-driven electrochemical system (SDES) was utilized to treat anaerobic digestate wastewater, aiming to achieve wastewater resource utilization and energy generation. The efficiencies of pollutant removal, resource recovery, and energy production were enhanced by adjusting device parameters (anode area, external resistance, and electrode spacing). The high pollutant removal rates and struvite purity were achieved with the magnesium anode area of 15 cm 2 , external resistance of 10 Ω, and electrode spacing of 10 cm. The appropriate anode area (3.0 cm 2 ), external resistance (50 Ω), and electrode spacing (7.5 cm) were prone to achieve high electric energy output. For one cycle, the removal rates of PO 4 3- -P and NH 4 + -N were 95.37% and 39.10%, respectively, with an average output power of 50.98W/m³, and 0.0275g of struvite was recovered(50 ml digested wastewater). For the long-term operation (20 cycles), the average PO 4 3- -P and NH 4 + -N removal rates were 89.3% and 23.4%, the CV (Coefficient of Variation)for PO 4 3- -P and NH 4 + -N were 0.1998 and 0.0504, and the average output power was 8.90 W/m 3 . The SDES showed satisfactory performance without replacing the magnesium anode. Based on the comprehensive efficiency of pollutant removal, resource recovery, and energy production, a replacement cycle of 20 cycles for magnesium anode was determined. In summary, the SDES for treating the anaerobic digested wastewater was demonstrated with stability and efficiency., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Classical and quantum nonreciprocity have important applications in information processing due to their special one-way controllability for physical systems. In this paper we investigate the nonreciprocal transmission and quantum correlation by introducing the dissipative coupling into a linear coupling system consisting of two microdisk resonators. Our research results demonstrate that even in the case of a stationary resonator, dissipative coupling can effectively induce nonreciprocity within the system. Moreover, the degree of nonreciprocity increases with the dissipative coupling strength. Importantly, the phase shift between the dissipative coupling and coherent coupling serves as a critical factor for controlling both nonreciprocal transmision and one-way quantum steering. Consequently, the introduction of dissipative coupling not only enhances the nonreciprocal transmission and nonreciprocal quantum correlation but also enables on-demand manipulation of nonreciprocity. This highlights dissipation as an effective means for manipulating classical and quantum nonreciprocity, thus playing a favorable role in chiral quantum networks.

Due to the wide sources of biomass raw materials and the lack of limits for the endogenous pollutants in biochar and their dosage, some biochar with high endogenous pollutants may be used for environmental remediation, which results in potential environmental risks. In this study, three biochars were prepared from the straws of Pennisetum sp. grown in clean, moderately polluted and highly polluted soils, respectively. The total endogenous copper (Cu) and cadmium (Cd), acid-soluble fraction, and persistent free radical (PFRs) distribution in biochars were investigated, and their biotoxicities were evaluated based on wheat root elongation inhibition rate and antioxidant enzyme activity. The results indicated that total Cu in Jiuniu biochar from the highly polluted soil and total Cd in Shuiquan biochar from the moderately-polluted soil were 3.73 and 4.43 times higher than that in Hongrang biochar from the clean soil, respectively. Moreover, acid-soluble Cu in Jiuniu biochar was 3.32 and 2.84 times higher than that in Shuiquan and Hongrang biochar, respectively, and acid-soluble Cd in Shuiquan and Jiuniu biochar was 7.95 and 5.11 times higher than that in Hongrang biochar, respectively. All three biochars had PFRs with adjacent oxygen atoms centered on carbon and followed the order of Hongrang>Jiuniu>Shuiquan. Three biochar leaching solutions significantly inhibited wheat root elongation but enhanced the enzyme activities of SOD, POD, and CAT for the wheat seedlings compared with that in the control. In particular, the highest inhibition rate (27.7%) was found in Jiuniu biochar. This study indicated that the interaction of endogenous heavy metals and PFRs in biochar exhibited significant biotoxicity to wheat seedlings. In the future, more attention should be paid to the potential environmental toxicity of endogenous pollutants from biochar to avoid new environmental pollution problems.

Aim: The underlying mechanisms by which circular RNAs (circRNAs) regulate non-small-cell lung cancer (NSCLC) progression remain elusive. This study investigated the role of circRNA circTTBK2 in NSCLC tumorigenesis. Materials & methods: Quantitative reverse transcriptase polymerase chain reaction analysis of circTTBK2 in NSCLC tissues and cell lines was performed. Cell proliferation, migration, invasion and tumorigenesis were confirmed in vitro and in vivo using CCK-8, EdU incorporation, Transwell assays and xenograft technique. The circTTBK2/miR-873-5p/TEAD1/DERL1 axis was verified by RNA immunoprecipitation, chromatin immunoprecipitation and luciferase reporter assays. Results: Overexpressed circTTBK2 in NSCLC tissues indicates poor prognosis of NSCLC patients. circTTBK2 harbors miR-873-5p, and miR-873-5p directly targets TEAD1. TEAD1 transcriptionally activates DERL1. Conclusion: This study revealed a novel machinery of circTTBK2/miR-873-5p/TEAD1/DERL1 for NSCLC tumorigenesis.

Background: The aim of the study was to evaluate the efficacy of abdominopelvic lymphatic drainage area irradiation (APLN), instead of whole abdominal radiotherapy (WART), in the consolidative radiotherapy of advanced ovarian carcinoma patients., Methods: We conducted a retrospective analysis collecting 99 patients with locally advanced ovarian cancer treated by APLN with 45 - 50 Gy/25- 28 fractions/5-7#, instead of WART. We evaluated the clinical outcome of APLN. Five patients were selected for dosimetric verifications verses WART (30 Gy/20 fractions). The normal tissue complication probability (NTCP) was calculated for the two treatment methods., Results: The mean follow-up time was 64.10 months (5.5 - 113.2 months), after APLN consolidative radiotherapy, 1-, 3-, and 5-year overall survival (OS) was 87.9%, 81.3%, and 61.5%, median disease-free survival (DFS) was 40.8 months, 5-year local recurrence free survival (LRFS) was 75.9%, and 5-year distant metastasis free survival (DMFS) was 49.2%. One patient died due to intestinal perforation. Local recurrence in the area between WART and APLN was rare (3/99 patients). The number of surgical procedures < 2 was an independent risk factor for LRFS (P = 0.023). Dosimetric comparison showed that comparing with WART, APLN significantly reduced the organ at risk (OAR) dose: 25.37 ± 3.63 Gy (25%) for liver, 8.77 ± 5.03 Gy (25%) for kidney, 8.14 ± 1.51 Gy (25%) for small intestine, etc. NTCP was reduced by 0.04-1.04% for liver, kidney, and small intestine., Conclusion: For consolidative radiotherapy in locally advanced ovarian cancer, APLN (intensity-modulated radiotherapy 45 - 50 Gy/25 - 28 fractions) could be an alternative to WART, resulting in excellent LRFS and DFS, with acceptable toxicities, comparing with previous literature reports. Dosimetric analysis also showed the benefits of APLN in NTCP., Competing Interests: None to declare., (Copyright 2022, Shen et al.)

Insertion/deletion polymorphism (InDel) genetic markers refer to insertion or deletion of DNA fragments into genomic DNA, which have advantages in the identification of degraded samples. In this study, we independently screened 66 highly polymorphic InDel markers from the dbSNP database to establish a multiplex PCR system for forensic DNA identification using next-generation sequencing system (66-plex InDels). We assessed the population genetic data among 251 Chinese Han population using this system and evaluated their potential forensic application. The results showed that all 66 InDel loci conformed to the Hardy-Weinberg equilibrium (P>0.000 758), and all the pairwise InDel loci were in linkage equilibrium after Bonferroni correction. The mean observed heterozygosity (Ho) was 0.482, the mean expected heterozygosity (He) was 0.483,the mean discrimination power (DP) was 0.612, the mean polymorphism information content (PIC) was 0.365, the total discrimination power (TDP) reached 0.999 999 999 999 999 999 999 999 999 428 18. The cumulative power of exclusion for 66 InDel loci was 0.999 739 in duo cases (CPE duo ) and was 0.999 999 999 417 in trios cases (CPE trio ). The results show that the 66 InDel loci have high genetic polymorphisms in the Chinese Han population and can be used independently for forensic DNA identification and paternity testing.

To improve nicotinic acid (NA) yield and meet industrial application requirements of sodium alginate-polyvinyl alcohol (SA-PVA) immobilized cells of Pseudomonas putida mut-D3 harboring nitrilase, inorganic materials were added to the SA-PVA immobilized cells to improve mechanical strength and mass transfer performance. The concentrations of inorganic materials were optimized to be 2.0% silica and 0.6% CaCO 3 . The optimal pH and temperature for SA-PVA immobilized cells and composite immobilized cells were both 8.0 and 45 °C, respectively. The half-lives of composite immobilized cells were 271.48, 150.92, 92.92 and 33.12 h, which were 1.40-, 1.35-, 1.22- and 1.63-fold compared to SA-PVA immobilized cells, respectively. The storage stability of the composite immobilized cells was slightly increased. The composite immobilized cells could convert 14 batches of 3-cyanopyridine with feeding concentration of 250 mM and accumulate 418 g ·L -1 nicotinic acid, while the SA-PVA immobilized cells accumulated 346 g L -1 nicotinic acid.

Objective: To compare the different pregnancy outcomes of women with a reduced dichorionic triamniotic (DCTA) triplet managed with radiofrequency ablation (RFA) or potassium chloride (KCL)., Materials and Methods: This was a retrospective cohort study. We studied 30 women of DCTA triplets managed with RFA as well as 85 managed with KCL. We compared the mean neonatal birthweight, median gestational age and perinatal mortality of two groups., Results: The mean neonatal birthweight of children in RFA group was 2572.4 g (SD, 407.0), vs 2899.3 g (SD, 554.9) in KCL group (P < 0.001). The rate of low birth weight infants was 23 (42.6%) vs. 16 (18.0%), respectively, (p < 0.005). However, there was no statistically significant difference in the median gestational age of delivery, premature birth before 32&37 weeks' gestation, neonatal brain injury or successful pregnancy between two groups. (We define the successful pregnancy as the condition that at least one child survives for a specific woman, while the failed one as no child survives.) CONCLUSION: What we took it for granted was that pregnancy outcomes in women with a reduced DCTA triplet managed with RFA was riskier than with KCL, however, we proved that it is not accurate. For women with a reduced DCTA triplet, managed with RFA is not much riskier than with KCL. What's more, most women have two children survived in RFA group, while in KCL group, only one child survives for most women. This result may change the management alternative for those women with DCTA triplet pregnancies who choose reduction, especially for women who desire to have two surviving and healthy fetuses., (Copyright © 2019. Published by Elsevier B.V.)

Background: Crocin is the major chemical constituent of the Chinese herb saffron. A number of studies have indicated that crocin induces an antitumor effect by inhibiting proliferation and inducing the apoptosis of tumor cells. However, the effect of crocin on tumor angiogenesis remains unknown., Methods: The effects of prolonged crocin exposure on breast cancer cell MDA-MB-231, human umbilical vein endothelial cells (HUVECs) and mice were examined., Results: Crocin had a profound effect on the morphology and proliferation rate of MDA-MB-231 and HUVECs. Furthermore, crocin induced apoptosis and cell cycle arrest at the G2/M phase in MDA-MB-231 cells in a dose-dependent manner. This confirms that crocin induces the inhibition of HUVECs. Furthermore, the expression of CD34 in tumor tissues decreased after crocin treatment., Conclusions: Crocin has an anti-angiogenesis effect that may be correlated to the decreased expression of CD34. Crocin is likely to be involved in the regulation of molecules in the angiogenesis pathway., Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare., (2019 Journal of Thoracic Disease. All rights reserved.)

Background: First flower node (FFN) is an important trait for evaluating fruit earliness in pepper (Capsicum annuum L.). The trait is controlled by quantitative trait loci (QTL); however, studies have been limited on QTL mapping and genes contributing to the trait., Results: In this study, we developed a high density genetic map using specific-locus amplified fragment sequencing (SLAF-seq), a high-throughput strategy for de novo single nucleotide polymorphism discovery, based on 146 recombinant inbred lines (RILs) derived from an intraspecific cross between PM702 and FS871. The map contained 9328 SLAF markers on 12 linkage groups (LGs), and spanned a total genetic distance of 2009.69 centimorgan (cM) with an average distance of 0.22 cM. The sequencing depth for the map was 72.39-fold in the male parent, 57.04-fold in the female parent, and 15.65-fold in offspring. Using the genetic map, two major QTLs, named Ffn2.1 and Ffn2.2, identified on LG02 were strongly associated with FFN, with a phenotypic variance explanation of 28.62 and 19.56%, respectively. On the basis of the current annotation of C. annuum cv. Criollo de Morelos (CM334), 59 candidate genes were found within the Ffn2.1 and Ffn2.2 region, but only 3 of 59 genes were differentially expressed according to the RNA-seq results. Eventually we identified one gene associated with the FFN based on the function through GO, KEGG, and Swiss-prot analysis., Conclusions: Our research showed that the construction of high-density genetic map using SLAF-seq is a valuable tool for fine QTL mapping. The map we constructed is by far the most saturated complete genetic map of pepper, and using it we conducted fine QTL mapping for the important trait, FFN. QTLs and candidate genes obtained in this study lay a good foundation for the further research on FFN-related genes and other genetic applications in pepper.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor in Chief due to objections raised by persons identified as co-authors of corresponding author Bo Liu. The University of Macau states that Bo Liu is not affiliated with the University of Macau. The purported co-authors who are only affiliated with University of Macau report their names have been misappropriated for use on this paper without notice or prior permission. These co-authors deny any involvement in the study, preparation or submission of the manuscript, or review of any supporting data. The purported co-authors who are affiliated with the University of Maryland, Baltimore report their names and credentials have been misappropriated for use on this paper without notice or permission. These co-authors deny any involvement in the study, preparation or submission of the manuscript, or review of any supporting data. The National Institute of Health also states that none of the co-authors are affiliated with the institution. The University of Maryland, Baltimore states that Bo Liu is not affiliated with the university. Bo Liu has been non-responsive to approaches from the Publisher. Rui Li and Ting-Ting Dong were not reachable by the Publisher. Lin Lin confirmed the affiliation with The University of California Riverside; Chu-Xia Deng confirmed the affiliation with the University of Macau; Wei-Min Tong confirmed the affiliation with the Chinese Academy of Medical Sciences., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The constitutively expression system for P. putida nitrilase was firstly constructed to improve the nicotinic acid production and reduce the production costs. High density culture strategy was employed to enhance the biomass and nitrilase production of recombinant strain. The total nitrilase activity reached up to 654 U·mL -1 without the induction. 541 g·L -1 nicotinic acid was accumulated via fed batch mode of substrate feeding through 290 min of conversion., (Copyright © 2018. Published by Elsevier Ltd.)

Eight compounds were isolated from the seeds of Holarrhena antidysenterica Wall.ex A.DC. On the basis of physico-chemical properties and spectroscopic data, holarrhenanan (1) was identified as a new compound, compounds 2-3 were isolated from H. antidysenterica for the first time, and five known compounds were also obtained. Inhibitory effects of some compounds and extracts to the intestinal peristalsis were evaluated. Results showed that the extracts and compounds 4, 6 exhibited remarkable inhibitory effects with tension inhibition rate of 32.77, 32.77% and amplitude inhibition rate of 59.51, 55.98%, respectively on the vitro rabbit intestinal peristalsis.

The objective of the study was to enhance the substrate tolerance of Pseudomonas putida nitrilase via atmospheric and room temperature plasma (ARTP) and cell immobilization. The mutant library was constructed by ARTP and rapidly screened by an OPA-TCA microscale reaction. A mutant strain of mut-D3 was obtained and its optimum substrate concentration was improved to 150mM from 100mM. It could accumulate 189g/L nicotinic acid (NA) from 3-cyanopyridine (3-CP), which was increased by 42% compared with that of wild type (WT). Additionally, composite immobilization of mut-D3 was performed and SA-PVA immobilized cells could catalyze 250mM 3-CP each batch with finally accumulating 346g/L NA, while free cells accumulated 175g/L NA. These results indicated that the free or immobilized catalysts of mut-D3 could serve as a good choice for NA production. This is the first report on mutation breeding of nitrilase-producing microorganisms by ARTP., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Two new steroidal alkaloids, isoconkuressine and N-formylconessimine, together with 6 known steroidal alkaloids including conkuressine, conessine, isoconessimine, conimine, conarrhimine, and funtudienine, were isolated from the seeds of Holarrhena antidysenteriaca Wall.ex A.DC. Their intrinsic antibacterial activities and synergistic effects with penicillin and vancomycin were analyzed in methicillin sensitive staphylococcus aureus (MSSA) and methicillin resistant staphylococcus aureus (MRSA). Two of the steroidal alkaloids including one new compound (N-formylconessimine) showed potential antibacterial activity and possessed synergistic effects with penicillin and vancomycin, respectively., (Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

3-Hydroxypropionic acid (3-HP) is an important platform chemical in organic synthesis. Traditionally, 3-HP was produced by chemical methods and fermentation process. In this work, a novel enzymatic method was developed for green synthesis of 3-HP. A yeast strain harboring nitrile-hydrolyzing enzyme was newly isolated from environmental samples using 3-hydroxypropionitrile (3-HPN) as the sole nitrogen source. It was identified to be Meyerozyma guilliermondii CGMCC12935 by sequencing of the 18S ribosomal DNA and internal transcribed spacer, together with analysis of the morphology characteristics. The catalytic properties of M. guilliermondii CGMCC12935 resting cells were determined, and the optimum activity was achieved at 55 °C and pH 7.5. The enzyme showed broad substrate specificity towards nitriles, especially 3-HPN, aminoacetonitrile and 3-cyanopyridine. The presence of Ag + , Pb 2+ and excess substrate inhibited the enzyme activity, whereas 5% (v/v) ethyl acetate had a positive effect on the enzyme activity. M. guilliermondii CGMCC12935 resting cells by addition of 3% glucose could thoroughly hydrolyze 500 mM 3-HPN into 3-HP within 100 h and the maximal accumulative production of 3-HP reached 216.33 mM, which was over twofolds than the control group with no additional glucose. And this work would lay the foundation for biological production of 3-HP in industry.

Cation channel of sperm 1 (CATSPER1) is a unique sperm cation channel protein, and essential for sperm function and male fertility. CATSPER1 exclusively expresses in meiotic and postmeiotic spermatogenic cells, thus belongs to the spermatogenesis-specific antigen that escape central tolerance. We have previously demonstrated the immunocontraceptive potential of its transmembrane domains and pore region, and reported the antifertility effects of its B-cell epitopes on male mice. Aiming to develop DNA vaccine targeting CATSPER1 for male contraception, here the whole open reading frame of mouse Catsper1 was cloned into the plasmid pEGFP-N1 to obtain a DNA vaccine pEGFP-N1-Catsper1. The vaccine was confirmed to be transcribed and translated in mouse N2a cell in vitro and mouse muscle tissue in vivo. Intramuscular injection with the vaccine on male mice induced specific immune reaction and caused significant inhibition on sperm hyperactivated motility and progressive motility (P<0.001 for both), and consequently reduced male fertility. The fertility rate of experimental group was 40.9%, which was significant lower (P=0.012) than control group (81.8%). No significant change in mating behavior, sperm production and histology of testis/epididymis was observed. Given that Catsper1 exhibits a high degree of homology among different species, Catsper1 DNA vaccine might be a good strategy for developing an immunocontraceptive vaccine for human and animal use.

Characteristics of ecosystem carbon exchange and its impact factors in Artemisia ordosica shrubland in 2011 (low precipitation) and 2012 (high precipitation), Ordos Plateau, were studied using eddy covariance methods. The results showed that the diurnal dynamics of ecosystem carbon exchange could be expressed as single-peak and double-peak curves in the two different precipitation years. In 2011, three carbon absorption peaks and three carbon release peaks of ecosystem carbon exchange presented in the growing season. In 2012, four carbon absorption peaks and one carbon release peak appeared in the growing season. The A. ordosica shrubland was a net carbon sink from June to September and a carbon source in October in 2011. In 2012, A. ordosica shrubland was a net carbon sink in the whole growing season. The amount of carbon fixed by A. ordosica shrubland in the growing season in 2012 was 268.90 mg CO2 x m(-2) x s(-1) higher than that in 2011. The ecosystem carbon exchange of A. ordosica shrubland was controlled by PAR (photosynthetically active radiation) on the day scale, and affected by both abiotic (precipitation and soil water content) and biotic (aboveground net primary, productivity) factors on the growing season scale.

Objective: To investigate the characteristics of post-transplantation diabetes mellitus and analyze its risk factors., Methods: Extensive survey was carried out to understand the characteristics of posttransplantation diabetes mellitus in patients who received kidney grafting from February 1984 to December 2006., Results: Three hundred forty-four post-transplantation diabetes mellitus patients from 1872 ones after kidney grafting were found from February 1984 to December 2006. The prevalence of new onset posttransplant diabetes mellitus and impaired fasting glucose in kidney allograft recipients were 18.4% and 12.7% respectively, being significantly higher than that in general population and other inpatients. The options of immunosuppressants were significantly associated with the prevalence of post-transplantation diabetes mellitus. By multivariate logistic regression analysis, the baseline characteristics of the post transplantation diabetes mellitus patients were significantly associated with increased age (OR: 1.309, P = 0.049), elevated level of the triglyceride ( OR: 1.311, P = 0.005), treatment with tacrolimus (FK506) (OR: 1.522, P = 0.008), and large dose of intravenous pulsed prednisolone (OR: 1.239, P = 0.011), as compared with patients without post-transplantation diabetes mellitus. Besides, the number of patients with at least one acute rejection episode was significantly greater in the post-transplantation diabetic patients. Mycophenolate mofetil (OR: 0.716, P = 0.028) and diltiazem (OR: 0.737, P = 0.015) were associated with lower risk of post-transplantation diabetes mellitus., Conclusions: High prevalence of abnormal glucose metabolism in renal allograft recipients during hospitalization was observed. Many risk factors contributed to the development of post transplantation diabetes mellitus.

Germline mutations in the RET proto-oncogene (RET gene) are well documented as the genetic causes of multiple endocrine neoplasia type 2A (MEN2A). We performed genetic analysis by direct RET gene mutation analysis in a Chinese MEN2A family and compared these results with biochemical screening tests and pathological examinations. Twenty-one exons and flanking introns of the RET gene were amplified using polymerase chain reaction (PCR). The PCR products were subjected to sequencing directly, or cloned into pGEM-T plasmids and sequenced. Restriction fragment length polymorphism (RFLP) was employed to confirm the mutation on the RET sequence. A novel heterozygous mutation of a 3-bp (GAC) deletion at codon 631 (D631del) of exon 11, resulting in the deletion of an aspartic acid at the locus, was identified in four MEN2A patients and one phenotypically normal family member. The average clinical onset-age of four MEN2A patients was 33.7 years, no cervical lymph node metastasis was found in MEN2A patients with medullary thyroid carcinoma in the family. The study indicated that the novel heterozygous deletion mutation at D631 of RET gene was co-segregated with MEN2A phenotype and promoted the development of MEN2A. This report is the first description of the D631del mutation in the family with MEN2A.

Objective: To detect the mutations of RET proto-oncogene in two Chinese families with multiple endocrine neoplasia type 2A (MEN2A) and to study the clinical application of pentagastrin stimulation test in the diagnosis and follow-up of MEN2A., Methods: In this study, there were 4 patients clinically diagnosed as MEN2A in the two pedigrees. PCR and direct gene sequencing of PCR products with an automated DNA sequencer were used to scan the entire 21 exons of RET proto-oncogene in the leukocyte DNA of 6 members of the two families. Blood calcitonin was measured and pentagastrin stimulation test carried out in all the 4 clinically diagnosed patients., Results: Two missense mutations were detected in exon 11 of the RET proto-oncogene. One was C634R in the 2 patients from one MEN2A family and the other was C634Y in 2 patients from another family. The basal serum calcitonin was very high (400.5 - 13 510.7 ng/L, normal range 16.6 - 132.8 ng/L) in the MEN2A patients and after pentagastrin stimulation the serum calcitonin level was significantly higher (494.1 - 33 901.9 ng/L)., Conclusions: Two mutations (C634R and C634Y) were detected in the patients of two families with MEN2A. Pentagastrin stimulation test was helpful for the diagnosis and follow-up after operative treatment of MEN2A.

Objective: To detect RET mutations in a rare Chinese big family with Multiple endocrine neoplasia type 2A (MEN2A)., Methods: One MEN2A family, including the proband, have 22 members of two generations, it is a rare big family in modern Chinese families. The DNAs of the 22 members from the family including 4 patients were extracted from blood leukocytes, PCR and gene sequencing of PCR products by an automated DNA sequencer were applied to scan the exon10 and 11 of RET proto-oncogene. Sequencing results were compared with the Pubmed's. Clone sequencing was adopt to further confirm the results, then verifying the novel mutation through the human gene mutation database at the institute of medical genetics in cardiff. Invitrogen biotechnology company (Shanghai) provided the technology of clone sequencing., Results: A novel deletion mutation of D631 (GAC) (del D631) was detected in exon11 of the RET proto-oncogene in 4 MEN2A patients of the family, this rare deletion mutation of D631 (GAC) lead base sequence of TGC(angle)GACGAGCTG change to TGCGAGCTG. Besides 4 MEN2A patients, the son of II6 (the first class relative) was found to be a carrier of delD631 mutation., Conclusion: A novel deletion mutation (del D631) of RET proto-oncogene was detected in the family with MEN2A and it has never been reported before in the world. DelD631 may be related to the late onset of MEN2A compared to the cysteine mutations and pheochromocytoma might be the first manifestation prior to the development of MTC.