[A prospective study on the development and application verification of the quantitative evaluation software for three-dimensional morphology of pathological scars based on photo modeling technology].

Objective: To develop a quantitative evaluation software for three-dimensional morphology of pathological scars based on photo modeling technology, and to verify its accuracy and feasibility in clinical application. Methods: The method of prospective observational study was adopted. From April 2019 to January 2022, 59 patients with pathological scars (totally 107 scars) who met the inclusion criteria were admitted to the First Medical Center of Chinese PLA General Hospital, including 27 males and 32 females, aged 33 (26, 44) years. Based on photo modeling technology, a software for measuring three-dimensional morphological parameters of pathological scars was developed with functions of collecting patients' basic information, and scar photography, three-dimensional reconstruction, browsing the models, and generating reports. This software and the clinical routine methods (vernier calipers, color Doppler ultrasonic diagnostic equipment, and elastomeric impression water injection method measurement) were used to measure the longest length, maximum thickness, and volume of scars, respectively. For scars with successful modelling, the number, distribution of scars, number of patients, and the longest length, maximum thickness, and volume of scars measured by both the software and clinical routine methods were collected. For scars with failed modelling, the number, distribution, type of scars, and the number of patients were collected. The correlation and consistency of the software and clinical routine methods in measuring the longest length, maximum thickness, and volume of scars were analyzed by unital linear regression analysis and the Bland-Altman method, respectively, and the intraclass correlation coefficients (ICCs), mean absolute error (MAE), and mean absolute percentage error (MAPE) were calculated. Results: A total of 102 scars from 54 patients were successfully modeled, which located in the chest (43 scars), in the shoulder and back (27 scars), in the limb (12 scars), in the face and neck (9 scars), in the auricle (6 scars), and in the abdomen (5 scars). The longest length, maximum thickness, and volume measured by the software and clinical routine methods were 3.61 (2.13, 5.19) and 3.53 (2.02, 5.11) cm, 0.45 (0.28, 0.70) and 0.43 (0.24, 0.72) cm, 1.17 (0.43, 3.57) and 0.96 (0.36, 3.26) mL. The 5 hypertrophic scars and auricular keloids from 5 patients were unsuccessfully modeled. The longest length, maximum thickness, and volume measured by the software and clinical routine methods showed obvious linear correlation (with r values of 0.985, 0.917, and 0.998, P<0.05). The ICCs of the longest length, maximum thickness, and volume of scars measured by the software and clinical routine methods were 0.993, 0.958, and 0.999 (with 95% confidence intervals of 0.989-0.995, 0.938-0.971, and 0.998-0.999, respectively). The longest length, maximum thickness, and volume of scars measured by the software and clinical routine methods had good consistency. The Bland-Altman method showed that 3.92% (4/102), 7.84% (8/102), and 8.82% (9/102) of the scars with the longest length, maximum thickness, and volume respectively were outside the 95% consistency limit. Within the 95% consistency limit, 2.04% (2/98) scars had the longest length error of more than 0.5 cm, 1.06% (1/94) scars had the maximum thickness error of more than 0.2 cm, and 2.15% (2/93) scars had the volume error of more than 0.5 mL. The MAE and MAPE of the longest length, maximum thickness, and volume of scars measured by the software and clinical routine methods were 0.21 cm, 0.10 cm, 0.24 mL, and 5.75%, 21.21%, 24.80%, respectively. Conclusions: The quantitative evaluation software for three-dimensional morphology of pathological scars based on photo modeling technology can realize the three-dimensional modeling and measurement of morphological parameters of most pathological scars. Its measurement results were in good consistency with those of clinical routine methods, and the errors were acceptable in clinic. This software can be used as an auxiliary method for clinical diagnosis and treatment of pathological scars.

Efficacy and safety of HSK3486 for the induction and maintenance of general anesthesia in elective surgical patients: a multicenter, randomized, open-label, propofol-controlled phase 2 clinical trial.

OBJECTIVE: To evaluate the efficacy and safety of HSK3486 for the induction and maintenance of general anesthesia in elective surgical patients, but excluding emergency, cardiothoracic, cerebral and endoscopic sinus cases. PATIENTS AND METHODS: A total of 40 eligible patients were randomly assigned to HSK3486 (n = 30) or propofol (n = 10) dosage groups in a ratio of 3:1. Drugs were administered as a bolus injection of 0.4 mg/kg (HSK3486) or 2.0 mg/kg (propofol) for induction, followed by maintenance infusion with the same anesthetic. An additional 6 non-randomized patients received propofol (2.0 mg/kg) for induction and were given HSK3486 for maintenance. RESULTS: The primary efficacy endpoint - the success rate of anesthesia maintenance - was 100% in the 3 arms. The secondary efficacy endpoints included times from discontinuation of HSK3486 or propofol maintenance to full alertness, respiratory recovery, extubation and reaching the goal of the Aldrete score. Also, the proportion of patients who constantly maintained BIS40-60 or those with a period of BIS40-60 during maintenance anesthesia showed no significant difference in the HSK3486 and propofol groups (all p > 0.05). Patients who received HSK3486 exhibited a higher satisfaction score from anesthesiologists during the induction period (p = 0.024). The occurrence and types of treatment-emergent adverse events were similar among the 3 arms, both with a severity of grade 1 or 2. Drug-related hypotension occurred in 14 (46.7%) and 7 (70.0%) patients treated with HSK3486 and propofol, respectively. CONCLUSIONS: HSK3486 exhibited good efficacy for the induction and maintenance of general anesthesia and was well tolerated by patients who underwent elective surgery.

Spatiotemporal changes of CT manifestations in 110 patients with COVID-19 pneumonia.

OBJECTIVE: The aim of the study was to analyze spatiotemporal changes of CT manifestations in patients with COVID-19 pneumonia. PATIENTS AND METHODS: In this retrospective review, 110 patients with confirmed COVID-19 by RT-PCR form February 16, 2020, to March 28, 2020 were included. A total of 449 CT scans were reviewed. We analyze the type and distribution of lung abnormalities, and CT general assessment and lesion area statistics were performed. Patients were divided into mild, moderate, and severe disease based on Chinese guidelines: mild (patients with minimal symptoms, CT scans showed no pneumonia or a small area of pneumonia infection), moderate (different extent of clinical manifestations and CT scans showed multiple pneumonia infections in both lungs), severe disease (respiratory distress, CT scans lesion area exceeds 50%, and the lesion contains consolidation). The proportion of patients with mild, moderate and severe diseases was counted. RESULTS: The CT score and the area involved reached a peak (median 10) on illness days 7-12, and then, continued to be at a high level. The main abnormal pattern after symptoms appeared GGO (36/94 [36%] to 40/65 [62%] in different periods). The proportion of mixed reached its peak on illness days 13-18 (36/93 [39%]). Pure GGO was the most common subtype of GGO (24 of 60 CT scans [40%] to 23 of 33 CT scans [70%]) after symptoms onset. The ratio of GGO with irregular lines and interfaces peaked on illness days 7-12 (6/34 [18%]). The lesions are mainly distributed on both sides and under the pleura. 76/84 (90%) of discharged patients had residual lesions on the final CT scans. 4 confirmed patients' CT scans did not show lesions (on illness days 1-24 days). There were 47 mild cases (42.7%), 46 moderate cases (41.8%), and 7 severe cases (6.3%). CONCLUSIONS: The degree of lung abnormality on the CT of the patients reached the peak on the 7th to 12th days of the disease. CT performance changes with time have a certain regularity, which may indicate the progress and recovery of the disease. 90% of patients still observed residual lung abnormalities in CT images at the time of discharge. There were 4 confirmed cases where the CT images did not show the lesion; hence, CT cannot be used as a basis for judging COVID-19 as a single tool.

[Diagnostic value of thin-slice CT navigation combined with cytology in preoperative bronchoscopy of peripheral pulmonary lesions].

Objective: To evaluate the diagnostic value of thin-slice CT navigation combined with cytology in routine preoperative bronchoscopy of peripheral pulmonary lesions and compare the diagnostic effects of different cytological sampling methods. Methods: The clinical data of peripheral lung cancer patients with preoperative bronchoscopy and cytology sampling guided by thin-slice CT from May 2015 to July 2016 in Cancer Hospital, Chinese Academy of Medical Sciences were retrospectively analyzed. The diagnostic accuracy, sensitivity and specificity of different cytological sampling methods for peripheral pulmonary lesions guided by thin-slice CT were compared, the factors affected the diagnostic sensitivity were analyzed, and the complications induced by these methods were observed. Results: The diagnostic sensitivity of thin-slice CT navigation combined with bronchoalveolar lavage for peripheral pulmonary lesions was 39.1%, and the positive diagnosis rate was 35.1%. The diagnostic sensitivity of thin-slice CT navigation combined with cell brush for peripheral pulmonary lesions was 51.7%, and the positive diagnosis rate was 46.4%. The diagnostic sensitivity of bronchoalveolar lavage combined with cell brush for peripheral pulmonary lesions was 57.5%, and the positive diagnosis rate was 51.5%. The positive diagnosis rate between brush sampling and bronchoalveolar lavage was statistically different (P=0.01). No significant difference was observed in the diagnostic rate between cell brush and cell brush combined with bronchoalveolar lavage (P=0.06). The factors affected diagnostic sensitivity of brush included the lesion location, size, and the relationship between the lesion and bronchial (all P<0.05). When the size of the peripheral lung lesion >2 cm, the diagnostic sensitivity of thin-slice CT navigation combined with cell brush for peripheral pulmonary lesions was 73.6%. Its positive diagnosis rate was 68% and the specificity was 100%, respectively. Two cases of mild bleeding were observed, and hemorrhage was terminated by conservative treatment. Conclusion: Preoperative thin-slice CT navigation combined with cytological examination is an effective method for the diagnosis of peripheral pulmonary lesions, and the diagnostic efficiency of cell brush is higher than that of bronchoalveolar lavage, especially for the lesion size >2 cm.

[Comparison of Imaging and Pathologic Findings of Retroperitoneal Dedifferentiated Liposarcoma].

Objective: To investigate the imaging appearance of CT and MRI in retroperitoneal dedifferentiated liposarcoma (DDL) based on pathological findings. Methods: Twelve patients with retroperitoneal DDL (13 lesions) who were surgically and pathologically confirmed were retrospectively collected in the Cancer Hospital of Chinese Academy of Medical Sciences. The correlation of CT and MRI features with histopathologic findings was analyzed. Results: The CT and MRI images of retroperitoneal DDLs were large, heterogeneous soft-tissue masses, mostly lobulated (30.8%, 4/13) or multinodular (46.2%, 6/13), invading adjacent anatomic structures (46.2%, 6/13). The lesions contained different proportions of fatty and non-fatty components, and usually with clear boundaries. The CT images of dedifferentiated components showed non-fatty masses of soft tissue density or mixed density, among which ground-glass nodules may be related to mucinous components. Occasionally calcification or ossification was seen (45.5%, 5/11). The contrast-enhanced CT and MRI images of non-fatty components commonly showed intense heterogeneous enhancement (84.6%, 11/13), central cystic changes and necrosis (61.5%, 8/13), pathologically corresponding to multiple types of soft tissue sarcomas without significant specificity. The well-differentiated components were fatty masses with irregular fibrous septa or soft tissue nodules, which is pathologically corresponding to well differentiated liposarcoma. Lymph node or distant metastasis was rare. Conclusions: The imaging manifestations of retroperitoneal DDLs are diverse and closely related to the proportion and distribution of different components. CT, MRI and contrast-enhanced imaging has a certain diagnostic value for retroperitoneal DDLs.

Antioxidant effect of glutathione on promoting 2-keto-l-gulonic acid production in vitamin C fermentation system.

AIMS: Oxidative stress limited the growth of cells and 2-keto-l-gulonic acid (2-KGA) production in vitamin C (Vc) fermentation system. The study aims to investigate the antioxidant effect of glutathione on promoting 2-KGA in Vc fermentation system using Ketogulonicigenium vulgare 25B-1 and Bacillus endophyticus ST-1 as the co-culturing microbes. METHODS AND RESULTS: The activities of antioxidant-related enzymes and qPCR were used to study the antioxidant effect of glutathione addition in Vc fermentation system. The addition of GSH and GSH/GSSG increased 2-KGA production and decreased fermentation time, and the highest 2-KGA production increased by 40·63% and the lowest fermentation time shortened to 60 h when the addition of optimal concentration ratio of GSH/GSSG was 50 : 1. Moreover, the increased production of 2-KGA was accompanied by up-regulated the activities of total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), catalase (CAT) and over-expressed oxidative stress-related genes sod, gst, gr, zwf, gp, which resulted in scavenging reactive oxygen species to reduce oxidative stress in Vc fermentation system. CONCLUSIONS: Glutathione showed a significant effect on increasing 2-KGA production and decreasing fermentation time in Vc fermentation system. GSH/GSSG could maintain a dynamic balance with two forms of glutathione and the optimal concentration ratio of GSH/GSSG was 50 : 1. SIGNIFICANCE AND IMPACT OF THE STUDY: Glutathione is proved to be effective to relieve oxidative stress. The promotion effects of GSSG and GSH on 2-KGA production could help to further explore the optimization of co-culture fermentation process for Vc industrial production.

Fetal vitamin D concentration and growth, adiposity and neurodevelopment during infancy.

BACKGROUND/OBJECTIVES: To determine the association between cord blood 25-hydroxyvitamin D (25(OH)D) concentration with growth, adiposity and neurodevelopment during infancy. SUBJECTS/METHODS: Serum 25(OH)D was measured in cord blood by the liquid chromatography tandem mass spectrometry (LC-MS/MS) from the Shanghai's "Allergy and Obesity Cohort study" (n = 1244). Weight, length, head circumference, and body mass index (BMI) z-scores for age were calculated based on World Health Organization Standard (at 6 months, 1 years, and 2 years). Neurodevelopment was measured at 2 years using Ages and Stages Questionnaire. Generalized estimating equation and multivariable logistic regression model were exploited to examine associations between fetal 25(OH)D concentration and offspring outcomes. RESULTS: The median of the 25(OH)D concentration in cord blood was 22.4 ng/ml (interquartile range, 27.3-8.6). Infants born in winter had lower 25(OH)D concentration. 25(OH)D deficiency was not associated with weight z-score (mean difference, 0.07; 95% confidence internal (CI), -0.09 to 0.23), length z-score (mean difference, 0.01; 95% CI, -0.19 to 0.21), head circumference z-score (mean difference, -0.06; 95% CI, -0.27 to 0.15) and BMI z-score (mean difference, 0.09; 95% CI, -0.07 to 0.25) or neurodevelopment during infancy, adjusting for sex, socio-economic position, pre-pregnancy maternal BMI, and maternal and neonatal characteristics. The associations did not vary by gender. A sensitivity analysis of available case analysis showed virtually the same results. CONCLUSIONS: Fetal vitamin D concentration was not associated with growth, adiposity or neurodevelopment during infancy. The role of vitamin D concentration and its mechanistic pathway in the early origins of adiposity needs to be clarified.

[Role of Magnetic Resonance Imaging in distinguishing the origin of adenocarcinoma at the junction of the lower uterine segment and endocervix].

Objective: To evaluate Magnetic Resonance Imaging (MRI) at 3.0T in differential diagnosis of the origin of adenocarcinoma at the junction of the lower uterine segment and endocervix. Methods: 71 patients with adenocarcinoma at the junction of the lower uterine segment and endocervix were retrospectively collected. Pelvic MR examinations, including diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) sequences, were performed within 2 weeks before surgery. MR images were analyzed and measured by two radiologists, including the location of the tumor center, the enhancement pattern, the anterior and posterior diameters, the left and right diameters, the upper and lower diameters, and the apparent diffusion coefficient (ADC) of the tumor. Immunohistochemical method was used as gold standard in distinguishing cervical adenocarcinoma and uterine adenocarcinoma. Results: The upper and lower diameters of uterine adenocarcinoma were [(5.80±2.31) cm], significantly larger than those of cervical adenocarcinoma [(4.16±2.17) cm, P=0.009]. Using 4.5cm as the best cutoff point value, the sensitivity and specificity in distinguishing uterine adenocarcinoma and cervical adenocarcinoma were 68.4% and 65.4%, respectively. According to the location of tumor center, the sensitivity and specificity were 84.2% and 73.1%, respectively. Using tumor enhancement pattern as the criterion, the sensitivity and specificity of diagnosing uterine adenocarcinoma and cervical adenocarcinoma were 68.4% and 80.8% respectively. Conclusions: MRI has certain clinical value in evaluating the origin of adenocarcinoma at the junction of the lower uterine segment and endocervix. The lesions can be diagnosed according to the main location, the characteristics of dynamic enhancement and the growth pattern of the tumor.

The clinical study on the treatment for acute cerebral infarction by intra-arterial thrombolysis combined with mild hypothermia.

OBJECTIVE: This study was purposed to evaluate the clinical efficacy of the treatment for acute cerebral infarction by intra-arterial thrombolysis combined with mild hypothermia. PATIENTS AND METHODS: Thirty patients, diagnosed with acute anterior circulation cerebral infarction and admitted to the Hospital between January 2013 and September 2015, were randomly divided into the control group and the mild hypothermia group, each group comprising 15 cases. The treatment of intra-arterial thrombolysis combined with mild hypothermia was administered to the mild hypothermia group, while only the treatment of intra-arterial thrombolysis was performed on the control group. The National Institutes of Health Stroke Scale (NIHSS) score, Modified RANKIN Scale (MRS) score, cerebral hemorrhage transformation, pulmonary infection, and the incidence of gastrointestinal bleeding of the two groups were compared on day 14, 30, and 90 following the onset of the disease. RESULTS: The prognosis (MRS score) of the group with mild hypothermia combined with intra-arterial thrombolysis was lower than that of the group treated only with intra-arterial thrombolysis (p < 0.05). The incidence of cerebral hemorrhage transformation of the group with mild hypothermia combined with intra-arterial thrombolysis was also lower than that of the control group (p < 0.05). There was no significant difference in the incidence of pulmonary infection and gastrointestinal bleeding between the two groups. CONCLUSIONS: Treatment of patients suffering from acute cerebral infarction by means of intra-arterial thrombolysis in combination with mild hypothermia can result in reduced risk of hemorrhagic transformation and improve clinical outcome.

[The relationship among depression, anxiety, stress and addictive substance use behavior in 5 935 secondary vocational students].

Objective: To investigate the relationship among depression, anxiety, stress and addictive substance use behavior in secondary vocational students. Methods: Cluster sampling method and the Adolescent Health-related Behaviors Questionnaire were used to collect demographic characteristics, psychological symptoms, and addictive substance usage among 5 935 students in nine vocational schools in Chongqing, Zhaoqing, Ningbo, and Taiyuan. Multivariate logistic regression analysis was used to analyze the relationship between the addictive substance use behavior and psychological factors. Results: The detection rates of depression, anxiety and stress were 46.5% (n=2 762), 58.7% (n=3 483), and 29.8% (n= 1 770), respectively. The prevalence of addictive substances was 74.8% (n=4 440), traditional drugs was 0.8% (n=50), new drugs was 2.8% (n=166), other addictive drugs was 4.1% (n=241). Multivariate logistic regression analysis showed that compared with the normal psychological states of secondary vocational students, the OR value of mild depression tendency alcohol and tobacco use behavior of secondary vocational students was 1.45; the OR values of mild anxiety, moderate anxiety, severe anxiety and very serious anxiety were 1.46, 1.46, 1.71, and 1.83, respectively; the traditional drugs use behaviors were 5.51, and 2.61, respectively, for the severe anxiety and very serious anxiety. Compared with the normal psychological state of secondary vocational students, the OR values of the severe anxiety and very severe anxiety were 2.56, and 2.66, respectively, for severe anxiety and very serious anxiety. Compared with normal psychological status of secondary vocational students, the OR values of mild, moderate, severe, and very severe anxiety were 2.14, 2.47, 2.39, and 3.45, respectively; all P values <0.05. Conclusion: Anxiety and mild depression were risk factors of tobacco and alcohol use in secondary vocational students; severe and above anxiety were the risk factors of drug use in secondary vocational students; anxiety was the risk factor for other addictive drug use in secondary vocational students.

NSD2 promotes osteosarcoma cell proliferation and metastasis by inhibiting E-cadherin expression.

OBJECTIVE: Osteosarcoma is one of the most common malignant bone tumors. The mechanisms of osteosarcoma development and invasion have been studied for periods of time, yet targeted therapy for improving survival has not been well established. Histone lysine methyltransferase NSD2 was frequently overexpressed in multiple types of cancer such as multiple myeloma, stomach and colon cancer, and the overexpression of it usually associated with aggressiveness tumor type. However, the expression status and function of NSD2 are still ambiguous in osteosarcoma. MATERIALS AND METHODS: Here, we evaluate the abnormal expression levels of NSD2 in osteosarcoma samples and cell lines. The higher expression of NSD2 in tumors resulted in a poorer outcome and a worse 5-year overall survival. To investigate the role of NSD2 in osteosarcoma cell proliferation and invasion in vitro, MTT assay, cell cycle distribution, wound healing, transwell assay was performed in relative cell lines, using a recombinant lentivirus expressing NSD2 short hairpin RNA or NSD2 construction. RESULTS: Our results imply that NSD2 promotes osteosarcoma cell proliferation and invasion, and the mechanism was possibly through the suppression of E-cadherin and induction of the epithelial mesenchymal transition, further to proceed invasion of osteosarcoma cells. CONCLUSIONS: NSD2 may work as a novel repression of E-cadherin; therefore, NSD2 has potential as a target of OS therapy. In the future, the monitoring of NSD2 in the serum/plasma from the RNA level may be used as a non-invasive method for selecting patients for target therapy.

[Application of diffusion-weighted intravoxel incoherent motion imaging in diagnosis of renal cell carcinoma subtypes].

OBJECTIVE: To evaluate the value of parameters derived from intravoxel incoherent motion diffusion-weighted magnetic resonance imaging in differentiating histopathological subtypes of renal cell carcinoma (RCC). METHODS: Between May 2014 and December 2015, a total of 69 patients who were surgically and pathologically diagnosed as renal cell carcinoma were recruited for the study. We examined 61 clear cell RCC (ccRCC), and 8 non-clear cell carcinoma (non-ccRCC, including 7 chromophobe RCC and 1 papillary RCC). All the ccRCC were divided into well differentiated group (n=46), moderately differentiated group (n=8), and poorly differentiated group (n=7). In addition to routine renal magnetic resonance imaging examination performed on a 3.0-Tesla MR system, all patients were imaged with axial intravoxel incoherent motion diffusion-weighted imaging. Using biexponential model, we calculated the diffusion coefficient (D), pseudodiffusion coefficient (D(*)), and perfusion fraction (f). RESULTS: The D and f values of the ccRCC were higher (each P<0.05) than that for non-ccRCC [D (1.29±0.30)×10(-3)mm(2)/s, D(*) (42.92±20.21)×10(-3)mm(2)/s, and f (35.71±6.61)% versus D (0.78±0.23)×10(-3)mm(2)/s, D(*) (32.60±11.33)×10(-3)mm(2)/s, and f (21.52±8.44)% ]. In the well differentiated group of ccRCC, we found D of (1.36±0.29)×10(-3)mm(2)/s, D(*) (38.39±18.51)×10(-3)mm(2)/s, and f (36.40±6.96)%. The D, D(*,) f values of moderately differentiated lesions were (1.10±0.24)×10(-3)mm(2)/s, (59.90±20.23)×10(-3) mm(2)/s, and (32.88±4.02)%, respectively, those of the poorly differentiated group were (1.03±0.16)×10(-3)mm(2)/s, (53.28±18.74)×10(-3)mm(2)/s, and (34.42±6.21)%. The well differentiated group of ccRCC showed a higher D value than the moderately differentiated and poorly differentiated groups (each P<0.05). D(*) values were significantly lower for the well differentiated group than for the moderately differentiated group (P<0.05). The sensitivity and specificity of D values were 90.2% and 87.5% when focusing on the differentiation of ccRCC. For the diagnosis of ccRCC, the sensitivity and specificity of f values were 98.4% and 75.0%, respectively. CONCLUSIONS: IVIM-DWI can provide certain reliable value in evaluating pathological subtype and differentiation degree of renal cell carcinomas. D and f values are useful to distinguish ccRCC from non-ccRCC. D value is also promising for estimating the differentiation degree of ccRCC, and to indicate the biological behavior of RCC.

Molecular identification and genetic variation of varieties of Styphnolobium japonicum (Fabaceae) using SRAP markers.

Thirty-four Styphnolobium japonicum varieties were analyzed using sequence-related amplified polymorphism (SRAP) markers, to investigate genetic variation and test the effectiveness of SRAP markers in DNA fingerprint establishment. Twelve primer pairs were selected from 120 primer combinations for their reproducibility and high polymorphism. We found a total of 430 amplified fragments, of which 415 fragments were considered polymorphic with an average of 34.58 polymorphic fragments for each primer combination. The percentage of polymorphic fragments was 96.60%, and four primer pairs showed 100% polymorphism. Moreover, simple matched coefficients ranged between 0.68 and 0.89, with an average of 0.785, indicating that the genetic variation among varieties was relatively low. This could be because of the narrow genetic basis of the selected breeding material. Based on the similarity coefficient value of 0.76, the varieties were divided into four major groups. In addition, abundant and clear SRAP fingerprints were obtained and could be used to establish DNA fingerprints. In the DNA fingerprints, each variety had its unique pattern that could be easily distinguished from others. The results demonstrated that 34 varieties of S. japonicum had a relatively narrow genetic variation. Hence, a broadening of the genetic basis of breeding material is necessary. We conclude that establishment of DNA fingerprint is feasible by means of SRAP markers.

Induction and identification of Stylosanthes guianensis tetraploids.

Stylosanthes guianensis is an elite and important forage legume species, which is extensively cultivated in tropical areas. Polyploid breeding via exposure to colchicine is a conventional and practical method to improve varieties of S. guianensis. Terminal buds of S. guianensis Reyan No.5 seedlings were treated with different concentrations of colchicine (0.00, 0.05, 0.10, 0.15, 0.20, and 0.25%) for 24, 48, and 72 h. Morphological and cytological variants were observed at a frequency of <96% among transplanted seedlings. The cytogenetic analysis of young leaf cells was conducted on all variants to identify their ploidy levels. The most efficient procedure for tetraploid production was the treatment of seedling apical buds with 20% colchicine for 48 h, with the tetraploid induction rate being 10%. This is a relatively simple and reliable method for the production of tetraploidy in S. guianensis.