Laparoscopic left hemihepatectomy guided by indocyanine green fluorescence: A cranial-dorsal approach.

BACKGROUND: Advancements in laparoscopic technology and a deeper understanding of intrahepatic anatomy have led to the establishment of more precise laparoscopic hepatectomy (LH) techniques. The indocyanine green (ICG) fluorescence navigation technique has emerged as the most effective method for identifying hepatic regions, potentially overcoming the limitations of LH. While laparoscopic left hemihepatectomy (LLH) is a standardized procedure, there is a need for innovative strategies to enhance its outcomes. AIM: To investigate a standardized cranial-dorsal strategy for LLH, focusing on important anatomical markers, surgical skills, and ICG staining methods. METHODS: Thirty-seven patients who underwent ICG fluorescence-guided LLH at Qujing Second People's Hospital between January 2019 and February 2022 were retrospectively analyzed. The cranial-dorsal approach was performed which involves dissecting the left hepatic vein cephalad, isolating the Arantius ligament , exposing the middle hepatic vein, and dissecting the parenchyma from the dorsal to the foot in order to complete the anatomical LLH. The surgical methods, as well as intra- and post-surgical data, were recorded and analyzed. Our hospital's Medical Ethics Committee approved this study (Ethical review: 2022-019-01). RESULTS: Intraoperative blood loss during LLH was 335.68 ± 99.869 mL and the rates of transfusion and conversion to laparotomy were 13.5% and 0%, respectively. The overall incidence of complications throughout the follow-up (median of 18 months; range 1-36 months) was 21.6%. No mortality or severe complications (level IV) were reported. CONCLUSION: LLH has the potential to become a novel, standardized approach that can effectively, safely, and simply expose the middle hepatic vein and meet the requirements of precision surgery.

Long-term outcomes of combined radiofrequency ablation and multipronged ethanol ablation for the treatment of unfavorable hepatocellular carcinoma

PURPOSE: To evaluate the local efficacy, safety, and long-term outcomes of combined radiofrequency ablation (RFA) and multipronged ethanol ablation (EA) in the treatment of unfavorable hepatocellular carcinoma (HCC) and to determine the prognostic factors for survival. METHODS: Between August 2009 and December 2017, 98 patients with 110 unfavorable HCC nodules who underwent combined RFA and multipronged EA were retrospectively enrolled in the study. Unfavorable HCC was defined as a medium (3.1-5.0 cm) or large (5.1-7.0 cm) HCC nodule, a tumor located at a high-risk site, or a perivascular tumor. The treatment response, overall survival (OS), and recurrence-free survival (RFS) were analyzed. The Kaplan-Meier method and Cox proportional hazards regression model were used to evaluate the prognostic factors. RESULTS: Complete ablation was obtained in 80.9% (89/110) of the tumors after initial treatment. Major complications were observed in 3 (3.1%) patients. The cumulative incidence of local tumor progression (LTP) was 23.5% at five years, and no variable was found to be an independent predictive factor for LTP. The five-year OS and RFS rates were 41.9% and 34.0%, respectively. Multivariate analysis showed that the serum alpha-fetoprotein level, tumor size, presence of residual tumor after ablation, and extrahepatic metastases were significant prognostic factors for OS (P = 0.023, P = 0.030, P = 0.001, and P = 0.010, respectively). Tumor type and the number of tumors were predictive factors for RFS (P = 0.029 and P = 0.001, respectively). A perivascular tumor was not an independent predictive factor for OS or RFS. CONCLUSION: Combined RFA and multipronged EA is a safe and effective treatment for unfavorable HCC, especially for perivascular tumors.

Multidisciplinary treatment of pancreatic cancer: a case report.

Background: Carcinoma of the head of pancreas has a high malignant degree and the 5-year survival rate at 5%. For unresectable pancreatic cancer, the 5-year survival rate is even lower. The clinical diagnosis of pancreatic cancer is difficult, and surgical indications are difficult to grasp. Moreover, perioperative and postoperative management is complex, and patients with different conditions need more attention to implement a comprehensive diagnosis and treatment strategy. In the diagnosis and treatment of pancreatic cancer and even other cancers, multi-disciplinary diagnosis and treatment can provide reasonable, personalized and more effective plans for patients so that cancer patients can receive better treatment and improve their quality of life. The multi-disciplinary diagnosis and treatment model can respond to the complex needs to individual patients. Case Description: This model is designed according to each patient's comprehensive situation, including their clinical symptoms, biochemical indicators, body mass index, and psychological status, and the tumor position, pathological tissue typing, and invasion scope. Complications of tumors can be reduced if treatment is controlled and if radical treatments are used within a broader comprehensive care model, thereby improving the quality of life of patients to prolong their survival. In our case report, the overall survival is much longer than un-resectable pancreatic cancer (median overall survival 6-9 months. The female patient was 53 years old. Her chief complaints were yellow skin, yellow urine, and absorption emaciation for 1 month. The preliminary diagnosis was postoperative pancreatic cancer. CT reexamination suggested portal vein liver metastasis. Repeated gastrointestinal bleeding occurs over the course of the disease. Postoperative review suggested recurrence, and she was admitted to First Affiliated Hospital, Army Medical University. During the treatment, the disease progressed to gastrointestinal bleeding, ascites, and jaundice. Conclusions: After multidisciplinary treatment (MDT) discussion, targeted treatment strategies were developed to improve the symptoms and improve the quality of life of the patients.

MicroRNA-545-5p regulates apoptosis, migration and invasion of osteosarcoma by targeting dimethyladenosine transferase 1.

The metastasis of osteosarcoma is a major threat to both adolescents and young adults. Identifying novel targets that may prevent osteosarcoma metastasis is critical in developing advanced clinical therapies for treating this cancer. The present study aimed to explore the mechanism of microRNA (miR)-545-5p in the metastasis of osteosarcoma. The present study identified miR-545-5p as a potential target that was downregulated in both osteosarcoma clinical samples and cell lines, and in the latter, ectopically expressed miR-545-5p caused apoptosis. In addition, miR-545-5p exerted inhibitory effects in osteosarcoma migration and invasion. Overexpression of miR-545-5p induced xenograft growth inhibition in vivo. In addition, miR-545-5p targeted dimethyladenosine transferase 1 (DIMT1), an oncogenic protein that facilitates osteosarcoma proliferation, migration and invasion. Taken together, the results of the present study suggest that miR-545-5p functions as a tumor suppressor in osteosarcoma that promotes apoptosis, while inhibiting migration and invasion by targeting DIMT1. Taken together, the results of the present study suggest two potential novel targets for osteosarcoma treatment and metastasis prevention.

Combining NMR-Based Metabolic Profiling and Genome Mining for the Accelerated Discovery of Archangiumide, an Allenic Macrolide from the Myxobacterium Archangium violaceum SDU8.

An unprecedented 19-membered allenic macrolide archangiumide (1) was discovered from the myxobacterium Archangium violaceum SDU8 by integrating NMR-based metabolic profiling and genome mining. Its biosynthesis pathway was proposed based on the architectural analysis of the encoding trans-AT PKS genes and validated by isotope labeling. The methodology of combing 2D NMR-based metabolic profiling and bioinformatics-aided structure prediction, as exemplified by this study, is anticipated to improve discovery efficiency of a broader range of microbial "dark matter".

Application of Contrast-Enhanced Ultrasound in the Diagnosis of Solid Pseudopapillary Tumors of the Pancreas: Imaging Findings Compared With Contrast-Enhanced Computed Tomography.

OBJECTIVES: The purpose of this study was to assess the characterization and usefulness of contrast-enhanced ultrasound (CEUS) for diagnosing solid pseudopapillary tumors of the pancreas (SPTP) and compare the enhancement patterns with contrast-enhanced computed tomography (CECT). METHODS: Forty-three SPTP lesions proved by pathologic findings in 42 patients examined with CEUS and CECT were included in this study. The enhancement characteristics and typical CEUS features of the tumors were investigated. These characteristics were compared according to lesion sizes. The enhancement patterns of CEUS were compared with CECT. RESULTS: The most common enhancement levels of SPTP in the early phase and late phase for CEUS were isoenhancement (19 of 43 [44.2%]) and hypoenhancement (32 of 43 [74.4%]), respectively. The 4 most common enhancement patterns were hypo-hypo (16 of 43 [37.2%]), iso-iso (11 of 43 [25.6%]), hyper-hypo (8 of 43 [18.6%]), and iso-hypo (8 of 43 [18.6%]) enhancement. For the 43 SPTP lesions, typical CEUS features such as lesion membrane, intralesional vessel, and intralesional compartmentalization enhancements were detected in 30 (69.8%), 27 (62.8%), and 10 (23.2%) cases. Compared with CECT, isoenhancement during the early phase and hypoenhancement during the late phase were the most common imaging characteristics of CEUS. CONCLUSIONS: Lesion membrane, intralesional vessel, and intralesional compartmentalization enhancements are typical CEUS features of SPTP, especially for large lesions (lesion size ≥3.0 cm). Isoenhancement during the early phase and hypoenhancement during the late phase are the most common imaging characteristics of CEUS and CECT, making CEUS a viable alternative diagnostic method that is noninvasive.

The value of clinical and ultrasound features for the diagnosis of infantile hepatic hemangioma: Comparison with contrast-enhanced CT/MRI.

OBJECTIVES: To investigate the combined use of ultrasound together with clinical features to differentiate infantile hepatic hemangioma (IHH) from other focal liver lesions (FLLs) in children and to compare the efficacy of the combined method to that of CECT/MRI. METHODS: The location, number, size and appearance of the tumors were evaluated in 45 children with IHH. Another 45 children with FLL were randomly selected as a control group. Independent factors for predicting IHH versus FLLs were evaluated. The diagnostic performance of the clinical and ultrasound features was compared with CECT/MRI. RESULTS: Compared with the control FLL group, the IHH group had a younger age at diagnosis (P = 0.008), lower alpha-fetoprotein (AFP) levels (P = 0.000), smaller lesion sizes (P = 0.000), and a higher tumor proportion with a resistance index (RI) of <0.7. Multiple logistic regression analysis showed that age, size, RI and AFP were independent factors for predicting IHH. Receiver operating characteristic (ROC) curve analysis showed that the AUC (area under the curve) of the four combined independent factors was 0.881 (95% CI: 0.744-0.960), while the AUC for the CECT/MRI method was 0.905 (95% CI: 0.774-0.973), and the combined AUC for the independent factors and CECT/MRI was 0.929 (95% CI: 0.805-0.985). There were not statistically significant among the three AUCs (P > 0.05). CONCLUSIONS: CECT/MRI was the effective diagnostic indicator for IHH. However, the combined clinical and ultrasound diagnoses, including age at diagnosis, lesion size, RI and AFP, can achieve the same effectiveness as CECT/MRI.

[Detection of 16S rRNA methylase genes and genotypes in ESBLs-producing enterobacteriaceae isolates from urinary tract infections].

OBJECTIVE: To study the prevalence of 16S rRNA methylase genes in extended-spectrum-lactamascs (ESBLs)-producing Enterobacteriacea, and the correlations of 16S rRNA methylase genes with anminoglycoside resistnace. METHODS: Seventy-four ESBLs-producing Enterobacteriacea stains were isolated from urinary tract infections. Minimal inhibitory concentrations (MICs) of 5 aminoglycosides against the ESBLs-producing Enterobacteriacea were detected by two-fold agar dilution method. PCR amplification and DNA sequencing were used for screening and identifying 16S rRNA methylase genes. The clonality of 16S rRNA methylase gene positive ESBLs-producing Enterobacteriaceae was assessed by multilocus sequence typing (MLST). RESULTS: The bacterial resistant rates to gentamycin, netilmicin, tobramycin,amikacin and isepamicin were 93.4%, 18.4%, 13.2%, 5.3% and 5.3%, respectively. Tweenty-two out of 74 clinical isolates were 16S rRNA methylase genes positive (29.7%), including 18 armA gene and 7 rmtB gene, and 3 strains with both genes. The resistant rates of those 22 strains to gentamycin , netilmicin, tobramycin, amikacin and isepamicin were 100%, 100%, 59.1%, 18.2% and 18.2%, respectively. Among 19 E. coli isolates, seven sequence types (STs) were identified, named as ST117 (12 strains), ST2003 (2 strains), ST3843 (1 strain), ST915 (1 strain), ST844 (1 strain), ST2581 (1 strain) and ST2922 (1 strain). MLST showed that 3 K. pneumoniae isolates were nonclonal. CONCLUSION: 16S rRNA methylase genes were widely distributed in urinary ESBLs-producing Enterobacteriacea, showing obvious relationship with the resistance to aminoglycosides. The therapy of Amikacin or Isepamicin may be considered in UTIs with 16S rRNA gene positive ESBLs-producing Enterobacteriacea.

[Separation and purification of total flavonids of Astragalus membranaceus with ethanol/phosphate aqueous two-phase system].

OBJECTIVE: To study separation and purification of flavonids with ethanol/phosphate aqueous two-phase system. METHOD: The diversity of phase separation ability and the distribution of target products in various systems were taken as indicators to analyze aqueous two-phase extraction systems and phase diagrams formed by ethanol and some common salts, screen out EtOH/ K2HPO4 system as the optimla system for extracting total flavonids, and study the impact of proportion of components in EtOH/K2 HPO4 system on the partition coefficient and phase ratio of flavonids. RESULT AND CONCLUSION: The EtOH/K2 HPO4 system with omegaEtOH 36.05% and omegaKHPO4 18.20% has been proved as the optimal conditions for separating and purifying total flavonoids of Astragalus (TFA). Under this optimal condition, the partition coefficient and the extraction yield of TFA reached 10.33 and 96.6%, respectively. After extraction, the contents of A. membranaceus saponins and A. membranaceus polysaccharides in top and bottom phases were determined at the same time, showing that A. membranaceus saponins in the removal rate reached 92.01%, and A. membranaceus polysaccharides were totally concentrated in bottom water phase, indicating a removal rate of 100%. Therefore, this is beneficial to separate and purify total flavonids from A. membranaceus crude extracts.

A comparison of three-dimensional marginal adaptation among three all-ceramic crown systems.

PURPOSE: This study was to compare the marginal adaptation of single crown made of 3 different all-ceramic systems (IPS e.max, In-Ceram alumina, Kavo Everest) in vitro using a light-body silicone supported by a heavy-body silicone material. METHODS: The crowns were made for 1 extracted maxillary premolar prepared with a 0.8-mm chamfer margin and 6-degree tapered walls by milling. Ten crowns per system were fabricated. The horizontal marginal discrepancies, vertical marginal discrepancies and absolute marginal discrepancies were measured under an optical microscope at 39.2 magnification. The data were analyzed with one-way analysis of variance (ANOVA) using SPSS 13.0 software package. RESULTS: The results showed the mean values for horizontal marginal discrepancies were between 41.1µm and 44.9µm, for vertical marginal discrepancies were between 51.4µm and 71.7µm, and for absolute marginal discrepancies were between 66.2µm and 85.1µm. CONCLUSIONS: The horizontal marginal discrepancies, vertical marginal discrepancies and absolute marginal discrepancies of the three all-ceramic crown systems were within the clinically acceptable standard. However, the IPS e.max system and the Kavo Everest System showed a better marginal fit compared with the In-Ceram alumina system.

[Analysis on the changing trends of non-communicable diseases in Xinjiang Production and Construction Corps, from 1998 to 2008].

OBJECTIVE: To understand the changing trends of non-communicable diseases (NCDs) in Xinjiang Production and Construction Corps from 1998 to 2008. METHODS: A stratified-cluster random sampling based cross-sectional NCDs survey was carried out in 2008, and using the data of NCDs from the health service surveys in 1998 and 2004, in Xinjiang Production and Construction Corps. The prevalence rate of NCDs was standardization according to age proportion of the population being surveyed in 1998. RESULTS: In 1998, 2004 and 2008, the prevalence rates of NCDs in Xinjiang Production and Construction Corps were 17.26%, 25.61%, 24.85% while the Standardized rates of NCDs were 17.26%, 23.54% and 20.49% respectively. The prevalence rates of NCDs were statistically significant different in 35-, 45-, 55- and over 65 age groups in 1998, 2004 and 2008 which showed an consecutive upward trend. The prevalence rates of hypertension, diabetes, cerebrovascular disease, coronary heart disease and chronic obstructive pulmonary disease increased significantly from 1998 to 2008. The prevalence rate of hypertensive disease among 25- age group, diabetes among 35- age group, cerebrovascular disease and coronary heart disease among 45- age groups showed an increasing trend. CONCLUSION: Cardiovascular and cerebrovascular diseases, together with diabetes were the fastest increasing ones over the past 10 years and becoming the major diseases, making the Xinjiang Production and Construction Corps an aging population. NCDs should be prioritized in the health development plan. Targeted health education should be carried out in the whole population, together with other interventions as well as management programs on chronic diseases to reduce the prevalence of NCDs.

[Epidemiological survey on malaria situation in Motuo County of Tibet, China].

OBJECTIVE: To make an epidemiological investigation on malaria in Motuo County, Linzhi Prefecture of Tibet. METHODS: In July of the year 2006, the following activities were conducted in 2 selected villages from each of the three townships, i.e., Motuo, Dexing and Beibeng: malaria history survey among inhabitants in recent 2 years; collection of blood samples of inhabitants for examining malaria parasites, IFAT and detecting G6PD, respectively; mosquito collection in human dwellings and cattle shelters at night and various resting sites at day-time; mosquito collection by outdoor human baiting capture; classification and composition calculation of mosquito species and man biting rates; ELISA for detecting sporozoite infection of Anopheles. RESULTS: The mean rate of two-year malaria history was 8.98% (118/1314) and the parasite rate was 3.13% (38/1216, all P. vivax) in the inhabitants. The parasite positive rate among the feverish patients was 7.14% (3/42). IFAT revealed a malaria antibody rate of 40.24% (472/1173). The G6PD deficiency rate was 1.74% (21/1208). Five hundred and thirteen anopheline mosquitoes were caught. They were An. maculatus (474) which occupied 92.4% (474/513), An. peditaeniatus (35), An. kochi (3) and An. sinensis (1). The mean indoor density of An. maculatus was 4.75/night in human houses, and 69.5/night in cattle shelters. The outdoor human biting rate was 22.75/half-night/person, and the sporozoite rate of An. maculatus in anopheline saliva glands was 0 by ELISA. CONCLUSION: Motuo County is an endemic area of vivax malaria with An. maculatus as the potential vector.

Highly efficient Agrobacterium-mediated transformation of embryogenic cell suspensions of Musa acuminata cv. Mas (AA) via a liquid co-cultivation system.

A high efficient protocol of Agrobacterium-mediated transformation of Musa acuminata cv. Mas (AA), a major banana variety of the South East Asia region, was developed in this study. Male-flower-derived embryogenic cell suspensions (ECS) were co-cultivated in liquid medium with Agrobacterium strain EHA105 harboring a binary vector pCAMBIA2301 carrying nptII and gusA gene in the T-DNA. Depending upon conditions and duration of co-cultivation in liquid medium, 0-490 transgenic plants per 0.5 ml packed cell volume (PCV) of ECS were obtained. The optimum duration of inoculation was 2 h, and the highest transformation frequency was achieved when infected ECS were co-cultivated in liquid medium first for 12 h at 40 rpm and then for 156 h at 100 rpm on a rotary shaker. Co-cultivation for a shorter duration (72 h) or shaking constantly at 100 rpm at the same duration gave 1.6 and 1.8 folds lower transformation efficiency, respectively. No transgenic plants were obtained in parallel experiments carried on semi-solid media. Histochemical GUS assay and molecular analysis in several tissues of the transgenic plants demonstrated that foreign genes were stably integrated into the banana genome. Compared to semi-solid co-cultivation transformation in other banana species, it is remarkable that liquid co-cultivation was much more efficient for transformation of the Mas cultivar, and was at least 1 month faster for regenerating transgenic plants.

Induction and cryopreservation of embryogenic cultures from nucelli and immature cotyledon cuts of mango (Mangifera indica L. var Zihua).

In this paper, we described the direct somatic embryogenesis from both immature cotyledon cuts and nucelli in the same mango cultivar (Mangifera indica L. var Zihua), studied the effect of growth conditions of embryogenic cultures (EMs) on cryopreservation and compared the cryopreservation response of EMs induced from these two different explants. Histological studies demonstrated that EMs derived from nucelli could be induced directly from epidermal cells of both sides of nucelli, whereas EMs derived from cotyledon cuts were induced only from epidermal cells of the adaxial side of the cotyledons. EMs from either nucelli or cotyledon cuts could be maintained in liquid medium or on solid medium and cryopreserved using a vitrification procedure. Success of cryopreservation of EMs depended on the dehydration treatment and the defined growth conditions during culture but not on their origins. When EMs were sampled during their exponential growth phase in liquid medium and dehydrated with PVS(3) solution for 5 min, survival of the EMs induced from cotyledon cuts and nucelli reached 77.7 and 80%, respectively, after cryopreservation in liquid nitrogen for 24 h. Furthermore, when dehydrated with PVS(3) solution for 30 min, all EMs induced from cotyledon cuts and 96.7% of EMs induced from nucelli could survive after cryopreservation. Cryopreservation did not affect the plant regeneration potential of EMs through somatic embryogenesis. The protocols of somatic embryogenesis and cryopreservation of mango EMs established in this study may offer potential ways to improve mango germplasm conservation and genetic improvement.

Determination of trace lead by solid substrate room temperature phosphorescence enhancing method based on heavy atom effect and dissoluble manganese supramolecule containing rhodamine 6G luminescent particles.

Dissoluble manganese supramolecule containing rhodamine 6G luminescent particles (M2) are synthesized, based on dissoluble manganese supramolecule (M1) doping rhodamine 6G (R.6G), by crystalline method. The particle diameters of M1 and M2 determined by ETM are both of micron degree. M1 and M2 can emit solid substrate room temperature phosphorescence (SS-RTP) on filter paper. The transition probability from the singlet state (S1) to triplet state (T1) of the luminescent molecules was greatly enhanced, based on the increment of luminescent molecules for each spot and the heavy atom effect of certain amount of Pb2+. As a result, the phosphorescence intensity (Ip) of M2 was increased sharply, and the enhancing value of phosphorescence intensity (DeltaIp) is directly proportional to the concentration of Pb2+. Thus, a new method of SS-RTP enhancing for the determination of trace lead is established based on manganese supramolecule containing rhodamine 6G luminescent particles. The linear range of this method is 0.0040-0.400 pg spot-1 of Pb2+ (corresponding concentration, 0.01-1.0 ng mL-1; sample volume, 0.4 microL spot-1), with a detection limit (LD) of 0.0011 pg spot-1 (corresponding concentration, 2.8x10(-12) g mL-1 of Pb2+, n=11). For the working solutions containing 0.0040 and 0.40 ng mL-1 of Pb2+, they were determined repeatedly for seven times, respectively. The R.S.D.s were 3.2 and 3.8%, respectively. This method has good repeatability, sensitivity and high precision. It has been applied to the determination of trace lead in human hair and tea samples with satisfactory results.

Two three-dimensional metal-organic frameworks containing one-dimensional hydroxyl/carboxylate mixed bridged metal chains: syntheses, crystal structures, and magnetic properties.

Two novel three-dimensional complexes formulated as [M(3)(bime)2(mu3-OH)2(HO-BDC)2]n (M = Co, 1; Cu, 2) [bime = 1,2-bis(imidazol-1'-yl)ethane, HO-H2BDC = 5-hydroxyisophthalic acid] have been hydrothermally synthesized and characterized. Both 1 and 2 exhibit similar structural frameworks resulting from one-dimensional metal/oxygen chains extended by HO-BDC, but the bridging modes of HO-BDC and coordination environments of metal centers are different. Complexes 1 and 2 crystallize in the orthorhombic system, space group Pbcn, a = 18.458(2) [18.2119(12) for 2] Angstroms, b = 12.0616(14) [11.6847(7)] Angstroms, c = 11.4859(14) [12.0688(6)] Angstroms, and Z = 4 (4). Magnetic studies show that 1 displays a slow magnetic relaxation, a large hysteresis, and distinct finite-size effects and 2 contains an antiferromagnetic chain.

[Establishment of embryogenic cell suspension culture and plant regeneration of edible banana Musa acuminata cv. Mas (AA)].

Conventional breeding for dual resistance of disease and pest of Musa cultivars remains a difficult endeavor, as the plant is polyploidic and high in sterility. Biotechnological techniques, eg., genetic engineering, in vitro mutation breeding, or protoplast fusion, may overcome the difficulties and improve the germplasm. Establishment of a stable embryogenic cell suspension (ECS) is a prerequisite for any of the biotechnological breeding methods. In this study an embryogenic cell suspension was established from immature male flower of Musa acuminata cv. Mas (AA), a popular commercial variety of banana in the South-East Asian region. After culture for 5-6 months on callus induction media, which consisted of MS salts, different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), 4.1 micromol/L biotin, 5.7 micromol/L indoleacetic acid (IAA), 5.4 micromol/L naphthaleneacetic acid (NAA), other vitamins, 87 mmol/L sucrose, and solidified with 7 g/L agarose, meristematic globules and yellow, friable embryogenic cultures were induced from the explants of 1-15th row young floral hands of immature male flowers. Of the four treatments of 2,4-D, 9 micromol/L was the most effective on the callus induction, it transformed 40.96% and 7.45% of the cultivated male floral hands into callus and embryogenic callus respectively. The explants to produce highest frequency of the embryogenic calli were floral hands of 6 to 12th rows, which generated 5.79% of the embryogenic calli. Suspension cultures were initiated from these embryogenic calli in liquid medium supplemented with 4.5 micromol/L 2, 4-D. After sieving selection of the cultures using a stainless steel metallic strainer with pore sizes of 154 microm at 15 day intervals for 3 months, homogeneous and yellow embryogenic cell suspensions, composed of single cells and small cell aggregates, were established. Based upon the growth quantity and growth rate of ECS, it was determined that the appropriate inoculum was 2.0 mL PCV ECS/30 mL medium in 100 mL flask, and the appropriate subculture cycle was 15 days. Planting of 6 months old ECS on semi-solid medium of somatic embryo induction and development (MSD) resulted in approximately 280 x 10(3) somatic embryos/mL PCV ECS. MSD contained SH macronutrients, micro-nutrients, Fe-EDTA and MS vitamins supplemented with 4.5 micromol/L biotin, 680 micromol/L glutamine, 2 mmol/L proline, 100 mg/L malt extract, 1.1 micromol/L NAA, 0.2 micromol/L zeatin, 0.5 micromol/L kinetin, 0.7 micromol/L N6-(2-isopentenyl) adenine, 29 mmol/L lactose, 130 mmol/L sucrose and solidified with 2g/L gelrite. After 3 months of maturity on MSD, 17.28% of the somatic embryos were germinated on germination media (MG), consisted of MS salt, Morel and Wetmore vitamins, 0.2 micromol/L 6-BA, 1.1 micromol/L IAA, 87 micromol/L sucrose and solidified with 2 g/L gelrite; and 14.16% of the somatic embryos could develop into normal plantlets on rooting media contained the same composition as that of MG but without auxin and cytokinin.

[Cloning of cDNA fragments related to adventitious root formation from mango cotyledon section].

Two cut surfaces of mango cotyledon (distal and proximal cut surfaces) showed different capability of adventitious root formation, only proximal cut surface could be induced to form the roots and the distal cut surface did not. cDNA fragments related to adventitious root formation from the cut sections were isolated with suppressive subtractive hybridization. The forward substracted cDNA library was constructed using the cDNAs of distal (non-rooting) cut surface as driver and the cDNAs of proximal (rooting) cut surface as tester. Six positive clones were obtained by Virtual Northern blots. In this study, the putative up-regulated genes showed by sequence analysis were reported in mango for the first time, the deduced proteins among the positive clones were homologous to transporters, transcriptional regulators and enzymes.

[Identification of an auxin response factor-like protein cDNA from mango cotyledon section].

Auxin-responsive elements (AuxRE) interact with a new class of plant-specific transcription factors, auxin response factors (ARFs). Some of ARFs have been shown to repress or activate expression of genes with an AuxRE promotor element. In Arabidopsis, ARFs play important roles in early embryo development and vascular strand formation (ARF5), floral patterning (ARF3) and photo- and gravitropic responses (ARF7). Two cut surfaces (distal and proximal) of mango (Mangifera indica L. var. Zi-Hua) cotyledon showed different patterns of adventitious root formation, with only the proximal cut surface, but not the distal one, could be induced to form the roots. Thus, the mango cotyledon is a good system for studying adventitious root formation. A cDNA fragment homologous to the Arabidopsis auxin response factor-like protein and relates to adventitious root formation from the cut sections were isolated using suppressive subtractive hybridization (SSH). Two cDNA clones, designated as MiARF1 (mango auxin response factor 1 gene, GenBank accession number AY255705) and MiARF2 (mango auxin response factor 2 gene, GenBank accession number is AY300808), were identified by 3'RACE. MiARF1, 3 272bp long, contains an open reading frame (ORF) of 2 523bp, 5'UTR of 285bp and 3'UTR of 464bp, MiARF2, 1 474bp long, contains an ORF of 981bp, 5' UTR of 285bp and 3'UTR of 208bp. The deduced MiARF1 and MiARF2 are homologues of auxin response factor (ARF) family of transcriptional regulators, and show high similarity to ARF of Arabidopsis in conserved domains. The motifs of MiARF1 EL-WHACAGPL in DBD (DNA binding domain) and GDDPW in IV domain are identical to that of ARF-like protein of Arabidopsis. MiARF2 is identical to MiARF1 in a large part of DBD, but lacks a carboxyl-terminal domain containing conserved motifs III and IV. Virtual Northern blot showed that the expression of MiARF2 was high in rooting tissue of cultured cotyledon sections but low in non-rooting tissue, and the MiARF1 was expressed both in the rooting and non-rooting tissues. We suggest that the MiARF2 is related to adventitious root formation of mango cotyledon section.