Identification of a new HLA-G allele, HLA-G*01:19, by cloning and phasing

A new HLA-G allelic variant, HLA-G*01:19, was identified in a southern Chinese Han population by polymerase chain reaction-sequence-based typing (PCR-SBT), cloning and phasing. HLA-G*01:19 differs from HLA-G*01:04:01 by a nonsynonymous cytosine at position 99 in exon 2, resulting in amino acid change from valine to leucine at codon 34 of the mature HLA-G molecule.

Characterization of a novel MICA allele, MICA*012:05, by cloning and sequencing

A new MICA allelic variant, MICA*012:05, has been identified in a Chinese Mongolian population. Following polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning and sequencing. MICA*012:05 was linked to an HLA-A*24-C*01-B*55:02-DRB1*09 haplotype. MICA*012:05 differs from MICA*012:01 by a single synonymous C to T substitution at nucleotide position 269 in exon 3.

Clinical Evaluation of Human Umbilical Cord Mesenchymal Stem Cell Transplantation After Angioplasty for Diabetic Foot

Aims: The multilineage differentiation potential of human umbilical cord mesenchymal stem cells (HUCMSCs) holds therapeutic promise for non-healing ulcers and tissue regeneration. The present study evaluated the effects of HUCMSC transplantation after angioplasty for treatment of diabetic foot. Methods: Included in the study were 53 patients (72 limbs) with severe symptoms of Fontaine II-IV diabetic foot accompanied by varying degrees of lower extremity arterial disease. The patients were randomly apportioned to a control group (25 patients; 38 limbs) or an experimental group (28 patients; 34 limbs). Patients of both groups received interventional treatment with angioplasty; those in the experimental group also received HUCMSCs by endovascular infusion and injection around the foot ulcer. Results: Within the 3-month follow-up, relative to patients in the control group, those in the experimental group experienced significantly greater and more stable improvements in skin temperature, ankle-brachial pressure index, transcutaneous oxygen tension, and claudication distance. Notably, 3 months after treatment a significant increase in neovessels, accompanied by complete or gradual ulcer healing, was shown in the experimental group. In addition, no serious complications or adverse reactions were associated with the treatment. Conclusion: Therefore, our results indicate that HUCMSC transplantation after angioplasty is a safe and effective clinical therapy for severe diabetic foot.

Decreased miR-452 expression in human colorectal cancer and its tumor suppressive function

MicroRNA-452 (miR-452) is dysregulated in some human malignancies, and is correlated with tumor progression. However, its expression and function in human colorectal cancer (CRC) remain unclear. The aim of our study was to explore the effects of miR-452 in CRC tumorigenesis and development. Using reverse transcription quantitative real-time polymerase chain reaction, we detected miR-452 expression in CRC cell lines and primary tumor tissues. We also examined the association between miR-452 expression and clinicopathological factors. We then investigated the effects of miR-452 on the biological behavior of CRC cells. miR-452 expression was significantly downregulated in CRC compared with the adjacent noncancerous tissues. A low level of miR-452 was associated with larger tumor size, deeper invasion depth, and advanced TNM stage. Multivariate Cox regression analysis identified decreased miR-452 expression as an independent factor predicting poor prognosis for CRC patients. In addition, in vitro functional analysis showed that overexpression of miR-452 in HCT116 cells reduced cell proliferation, promoted cell apoptosis, and inhibited cell invasion and migration. These findings indicate that miR-452acts as a tumor suppressor in CRC, and would serve as a novel molecular therapeutic agent for the treatment of the disease.

[Effect of bariatric surgery on obstructive sleep apnea hypopnea syndrome with obesity in China]

Obesity has become one of the greatest public health concerns especially in China and obstructive sleep apnea-hypopnea syndrome (OSAHS) is prevalent among morbidly obese patients. Metabolic and bariatric surgery has been proved to be a typical multidisciplinary strategy for obese patients with OSAHS but no related bariatric surgical guideline for OSAHS was found by now. In this paper, we extend to share our preliminary single-center experiences in the multidisciplinary treatment of severe obese with OSAHS.

Characterization of a new HLA-A allele, HLA-A*02:07:08, by cloning and sequencing

In this report, we present a novel HLA-A*02:07 allele, HLA-A*02:07:08. HLA-A*02:07:08 was identified in an individual of Han ethnicity in Hunan province, southern China. Following polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning and sequencing. HLA-A*02:07:08 differs from HLA-A*02:07:01 by a single synonymous C to T substitution at nucleotide position 131 in exon 3.

Abdominal wall endometriosis occurring after cesarean section: an underestimated complication

The aim of the study was to review patients characteristics, describe the exact anatomic locations and size of the endometriosis in the abdominal wall, and discuss the factors that may contribute to mesh use during abdominal wall endometriosis (AWE) resection.

MATERIALS AND METHODS

Patients diagnosed with AWE in their surgical scars from January 2008 to December 2014 were documented. Descriptive data was collected and analyzed.

RESULTS

A total of 95 patients with an age ranging from 26 to 48 years, with a mean age of 33.5 ?5.0 years at the time of excision were analyzed. The mean diameter of the mass was 3.25 cm in the present series with an average of 4.97 cm in the mesh group by ultrasound. A total of 18 patients had mesh therapy for fascia defect compared with 77 non-mesh therapy patients. The size of the lesions, the mean duration of symptoms for painful mass, and level of the serum CA125 were statistically different between mesh group and non-mesh group (p < 0.05). Cases of endometriosis lesions limited to the adipose layer had significant lower chance of using mesh (p < 0.05). However, adipose layer endometriosis lesions that had penetrated through the fascia layer and invaded into rectus abdominis muscle layer with/without peritoneum layer had significant higher chance of using mesh (p < 0.05).

CONCLUSIONS

The more common position for scar endometriosis may be in the adipose layer at the corner of the surgical scar. Mesh therapy should be considered before surgery when the diameter of the abdominal wall mass detected by ultrasound is more than five em and/or when the lesions invade into rectus abdominis muscle with/without peritoneum tissues from adipose and fascia layers.

Effect of wound infiltration with ropivacaine or bupivacaine analgesia in breast cancer surgery: A meta-analysis of randomized controlled trials

BACKGROUND

Although not completely painless, breast-conserving surgery is considerably less painful than modified radical mastectomy. Local anesthetics are speculated to reduce postoperative pain when placed at the surgical site. Thus, we conducted a systematic review of randomized controlled trials to evaluate the efficacy of bupivacaine or ropivacaine analgesia for pain relief in breast cancer surgery.

METHODS

PubMed, Embase, the Cochrane Library, Scopus, and the ClinicalTrials.gov registry were searched for studies published up to July 2015. Individual effect sizes were standardized, and a meta-analysis was performed to calculate a pooled effect size by using random effects models. Pain was assessed using a visual analog scale at 1, 2, 12, and 24 h postoperatively. The secondary outcomes included complications and analgesic consumption.

RESULTS

We reviewed 13 trials with 1150 patients. We found no difference in postoperative pain reduction at 1, 12, and 24 h after breast cancer surgery between the experimental and control groups. The severity of pain was significantly reduced in the experimental group (weighted mean difference -0.19; 95% confidence interval: -0.39-0.00) at 2 h postoperatively. Moreover, postoperative analgesic consumption did not differ significantly between the groups. No major drug-related complication was observed in any study.

CONCLUSION

Administration of the local anesthetics bupivacaine or ropivacaine during breast cancer surgery decreased pain significantly at only 2 h but did not reduce pain at 12, and 24 h postoperatively.

Atomic-Scale Interfacial Magnetism in Fe/Graphene Heterojunction

Successful spin injection into graphene makes it a competitive contender in the race to become a key material for quantum computation, or the spin-operation-based data processing and sensing. Engineering ferromagnetic metal (FM)/graphene heterojunctions is one of the most promising avenues to realise it, however, their interface magnetism remains an open question up to this day. In any proposed FM/graphene spintronic devices, the best opportunity for spin transport could only be achieved where no magnetic dead layer exists at the FM/graphene interface. Here we present a comprehensive study of the epitaxial Fe/graphene interface by means of X-ray magnetic circular dichroism (XMCD) and density functional theory (DFT) calculations. The experiment has been performed using a specially designed FM₁/FM₂/graphene structure that to a large extent restores the realistic case of the proposed graphene-based transistors. We have quantitatively observed a reduced but still sizable magnetic moments of the epitaxial Fe ML on graphene, which is well resembled by simulations and can be attributed to the strong hybridization between the Fe 3d_z2 and the C 2p_z orbitals and the sp-orbital-like behavior of the Fe 3d electrons due to the presence of graphene.

Identification of a novel MICB allele, MICB*030, by cloning and sequencing

A novel MICB allele, MICB*030, has been identified in a healthy Chinese individual of Mongol ethnicity residing in northern China by polymerase chain reaction sequence-based typing (PCR-SBT) and confirmed by cloning and sequencing. MICB*030 was linked to HLA-B*35. Aligned with MICB*005:02, MICB*030 has a nonsynonymous adenine substitution at nucleotide position 50 in exon 3, leading to amino acid change from serine to arginine at codon 102 of the mature MICB molecule.

IL-8 -251T/A polymorphism is associated with susceptibility to acute pancreatitis

We conducted a case-control study to clarify the asso-ciations between inflammatory cytokine, including interleukin (IL)-1b, IL-6, IL-8, and IL-10, polymorphisms and risk of acute pancreatitis. Genotyping analyses of IL-1β+3954 C/T (rs1143634), IL-1β-511 C/T (rs16944), IL-6 -174 G/C (rs1800795), IL-6 -634 C/G (rs1800796), IL-8 -251T/A (rs4073), IL-10 -1082A/G (rs1800896), and IL-10 -819C/T (rs1800871) were conducted using polymerase chain reaction-restriction fragment length of polymorphism. Unconditional logistic regression analysis was utilized to assess the potential association be-tween genotype frequencies and risk of acute pancreatitis. Multivari-ate regression analyses showed that subjects carrying the IL-8 -251 AA genotype had a significantly increased risk of acute pancreatitis, with an adjusted odds ratio (95% confidence interval) of 1.55 (1.02-2.36). However, we found no significant association between IL-1β +3954 C/T, IL-1β -511 C/T, IL-6 -174 G/C, IL-6 -174 G/C, IL-6 -634 C/G, IL-10 -1082A/G, or IL-10 -819C/T polymorphisms and risk of acute pancreatitis. We found that the IL-8 -251T/A polymorphism was associated with a higher susceptibility to acute pancreatitis in a Chinese population.

Efficient identification of ornamental peach cultivars using RAPD markers with a manual cultivar identification diagram strategy

One of the most important uses of DNA markers is cultivar identification. However, no DNA fingerprint analysis strategy is available for making DNA markers helpful in practical plant cultivar identification, especially for the identification of a large number of cultivars. We developed a manual cultivar identification diagram strategy for efficient identification of plant cultivars, from which a cultivar identification diagram (CID) of genotyped plant individuals can be constructed manually. This CID could be used as a reference for quick identification of plant cultivars of interest. We used 11-mer RAPD primers to amplify DNA samples of 32 ornamental peach genotypes; all the cultivars were well distinguished by fingerprints from 6 primers. The utility of this CID was verified by identification of three randomly chosen groups of cultivars among the 32 ones that we selected. This CID generated will be useful for the identification of commercially important ornamental peach cultivars.

Mutational analysis of the terminal protein Tpg of Streptomyces chromosomes: identification of the deoxynucleotidylation site

The linear chromosomes and linear plasmids of Streptomyces are capped by terminal proteins (TPs) covalently bound to the 5' ends of the DNA. The TPs serve as primers for DNA synthesis that patches in the single-stranded gaps at the telomeres resulting from the bi-directional replication ('end patching'). Typical Streptomyces TPs, designated Tpgs, are conserved in sequence and size (about 185 amino acids), and contain a predicted helix-turn-helix domain and a functional nuclear localization signal. The Tpg-encoding gene (tpg) is often accompanied by an upstream gene tap that encodes an essential telomere-associating protein. Five lone tpg variants (not accompanied by tap) from various Streptomyces species were tested, and three were found to be pseudogenes. The lone tpg variant on the SLP2 plasmid, although functional, still requires the presence of tap on the chromosome for end patching. Using a combination of in vitro deoxynucleotidylation, physical localization, and genetic analysis, we identified the threonine at position 114 (T114) in Tpg of Streptomyces lividans chromosome as the deoxynucleotidylated site. Interestingly, T114 could be substituted by a serine without destroying the priming activity of Tpg in vitro and in vivo. Such T114S substitution is seen in and a number of pseudogenes as well as functional Tpgs. T114 lies in a predicted coil flanked by two short helixes in a highly hydrophilic region. The location and structural arrangement of the deoxynucleotidylated site in Tpg is similar to those in the TPs of phage ø 29 and adenoviruses. However, these TPs are distinct in their sequences and sizes, indicating that they have evolved independently during evolution. Using naturally occurring and artificially created tpg variants, we further identified several amino acid residues in the N-terminus and the helix-turn-helix domain that were important for functionality.

De novo symptoms and their impact on life quality in patients following transvaginal reconstructive pelvic surgery with polypropylene mesh

OBJECTIVE

To study the de novo symptoms and their impact on life quality in patients that underwent transvaginal reconstructive pelvic surgery (RPS) with polypropylene mesh.

MATERIALS AND METHODS

From May 2004 to March 2011, 114 severe pelvic organ prolapse (POP) patients with Stage III-IV by POP-Q system underwent RPS with polypropylene mesh. Patients completed pelvic floor distress inventory short form (PFDI-20) and pelvic floor impact questionnaire short form (PFIQ-7) preoperatively and repeated them at two and six months, and one year postoperatively.

RESULTS

Ninety-six (84%, 96/114), 85 (75%, 85/114), and 77 (68%, 77/114) patients, respectively, completed the questionnaires at two months, six months, and one year postoperatively. All patients had POP-Q staging scoring < or = I at one year after surgery. Nineteen (19.8%, 19/96) patients had mesh exposure at two and six months (7.8%, 6/77) at one year follow-up. Most vaginal and pelvic symptoms, urinary and obstructive defecation bothersome symptoms improved significantly at two months postoperatively and this improvement was maintained at the one year follow-up. Mean score of PFDI-20 and PFIQ-7 all improved significantly postoperatively at two and six months and at one year follow-up (p < 0.01). Fifty percent (48/96) of patients had postoperative de novo symptoms at the two months follow-up predominantly presented with bothersome vaginal discharge (35.4%, 34/96) and pelvic muscle symptoms (20.8%, 20/96). Patients with de novo symptoms had higher postoperative mean POPDI-6 and POPIQ-7 scores (p < 0.05) than those without at the two month follow-up, but no significant difference was seen at the six month and at one year follow-ups. Patients with bothersome vaginal discharge had higher vaginal mesh exposure rate (41.2%, 14/34) than patients without (8.1%, 5/62) (p = 0.0003). One year after operation, 77 (68%) patients completed the non-validated satisfaction questionnaire. Seventy-four (96%, 74/77) patients said that they were either 'very satisfied' or 'satisfied' with the outcome of their surgery, while three (4%, 3/77) reported unsatisfactory results.

CONCLUSIONS

De novo symptoms were common after transvaginal RPS with polypropylene mesh, but most of them were moderate and resolved within six months postoperatively and seldomly had a long-term negative impact on their quality of life. The impact of dyspareunia on patients' sexual function requires further research.

Assessing genetic divergence in interspecific hybrids of Aechmea gomosepala and A. recurvata var. recurvata using inflorescence characteristics and sequence-related amplified polymorphism markers

Conventional hybridization and selection techniques have aided the development of new ornamental crop cultivars. However, little information is available on the genetic divergence of bromeliad hybrids. In the present study, we investigated the genetic variability in interspecific hybrids of Aechmea gomosepala and A. recurvata var. recurvata using inflorescence characteristics and sequence-related amplified polymorphism (SRAP) markers. The morphological analysis showed that the putative hybrids were intermediate between both parental species with respect to inflorescence characteristics. The 16 SRAP primer combinations yield 265 bands, among which 154 (57.72%) were polymorphic. The genetic similarity was an average of 0.59 and ranged from 0.21 to 0.87, indicating moderate genetic divergence among the hybrids. The unweighted pair group method with arithmetic average (UPGMA)-based cluster analysis distinguished the hybrids from their parents with a genetic distance coefficient of 0.54. The cophenetic correlation was 0.93, indicating a good fit between the dendrogram and the original distance matrix. The two-dimensional plot from the principal coordinate analysis showed that the hybrids were intermediately dispersed between both parents, corresponding to the results of the UPGMA cluster and the morphological analysis. These results suggest that SRAP markers could help to identify breeders, characterize F(1) hybrids of bromeliads at an early stage, and expedite genetic improvement of bromeliad cultivars.

An improved strategy based on RAPD markers efficiently identified 95 peach cultivars

DNA markers have useful applications in cultivar identification. A novel analysis approach called cultivar identification diagram (CID) was developed using DNA markers in the separation of plant individuals. This new strategy is less time- and cost-consuming, has reliable results, and was constructed for fingerprinting. Ten 11-mer primers were used to amplify the genotypes; all 95 peach genotypes (from the National Peach Germplasm Repository, in Nanjing, China) were distinguished by a combination of 54 primers. The utilization of the CID among these 95 peach cultivars was also verified by the identification of three randomly chosen groups of cultivars. This identification showed some advantages including the use of fewer primers and easy separation of all cultivars by the corresponding primers marked in the right position on the CID. This peach CID could provide the information to separate any peach cultivars of these 95, which may be of help to the peach industry in China and for the utilization of DNA markers to identify other plant species.

Temperature-dependent ideal strength and stacking fault energy of fcc Ni: a first-principles study of shear deformation

Variations of energy, stress, and magnetic moment of fcc Ni as a response to shear deformation and the associated ideal shear strength (τ(IS)), intrinsic (γ(SF)) and unstable (γ(US)) stacking fault energies have been studied in terms of first-principles calculations under both the alias and affine shear regimes within the {111} slip plane along the <112> and <110> directions. It is found that (i) the intrinsic stacking fault energy γ(SF) is nearly independent of the shear deformation regimes used, albeit a slightly smaller value is predicted by pure shear (with relaxation) compared to the one from simple shear (without relaxation); (ii) the minimum ideal shear strength τ(IS) is obtained by pure alias shear of {111}<112>; and (iii) the dissociation of the 1/2[110] dislocation into two partial Shockley dislocations (1/6[211] + 1/6[121]) is observed under pure alias shear of {111}<110>. Based on the quasiharmonic approach from first-principles phonon calculations, the predicted γ(SF) has been extended to finite temperatures. In particular, using a proposed quasistatic approach on the basis of the predicted volume versus temperature relation, the temperature dependence of τ(IS) is also obtained. Both the γ(SF) and the τ(IS) of fcc Ni decrease with increasing temperature. The computed ideal shear strengths as well as the intrinsic and unstable stacking fault energies are in favorable accord with experiments and other predictions in the literature.

Dynamic characteristics of multisensory facilitation and inhibition

Multimodal integration, which mainly refers to multisensory facilitation and multisensory inhibition, is the process of merging multisensory information in the human brain. However, the neural mechanisms underlying the dynamic characteristics of multimodal integration are not fully understood. The objective of this study is to investigate the basic mechanisms of multimodal integration by assessing the intermodal influences of vision, audition, and somatosensory sensations (the influence of multisensory background events to the target event). We used a timed target detection task, and measured both behavioral and electroencephalographic responses to visual target events (green solid circle), auditory target events (2 kHz pure tone) and somatosensory target events (1.5 ± 0.1 mA square wave pulse) from 20 normal participants. There were significant differences in both behavior performance and ERP components when comparing the unimodal target stimuli with multimodal (bimodal and trimodal) target stimuli for all target groups. Significant correlation among reaction time and P3 latency was observed across all target conditions. The perceptual processing of auditory target events (A) was inhibited by the background events, while the perceptual processing of somatosensory target events (S) was facilitated by the background events. In contrast, the perceptual processing of visual target events (V) remained impervious to multisensory background events.

Improving quality of life of children with cerebral palsy: a systematic review of clinical trials

OBJECTIVE

To systematically review the impact of different interventions on quality of life (QoL) for children with cerebral palsy.

METHODS

English articles were sought from five major English databases from inceptions until March 2010. Keywords used consisted of four components (and their variants): (i) clinical condition: cerebral palsy; (ii) outcome measures: quality of life, well-being; (iii) study design: clinical trials; and (iv) target population: people aged 0-18.

RESULTS

Eight studies satisfied the inclusion criteria, all of which are of good to excellent quality (a Jadad score of 4 or above). The Pediatric Evaluation of Disability Inventory, the Pediatric Quality of Life Inventory, the TNO-AZL Children's Health-Related Quality of Life and the Caregiver Priorities and Child Health Index of Life with Disabilities were used to measure QoL. Significant positive results were reported by two studies using medicinal interventions (diazepam and intrathecal baclofen therapy, effect sizes 5.9, 9.1 respectively) and two studies employing motor control approach training (strength training and exercise training, former effect size being 3.8).

CONCLUSION

Current review suggests that positive effect was shown in medicinal and motor control interventions on QoL. However, no single interventional approach can demonstrate a consistent positive impact on QoL across different studies. Future studies are recommended to (i) provide a clear definition of QoL, and investigate the relationship between symptoms' severity and QoL; (ii) measure outcome at different time points to capture real effects of interventions; and (iii) make more use of valid outcome instruments, either self-report or parent/caregiver proxy reports.

[Application of flow cytometry to detect ABO blood group antibody levels in rhesus monkeys and cynomolgus monkeys]

Similar to humans, most of non-human primates also contain the ABO blood group system. In this study, we sought to evaluate the ABO antibody (Ab) levels in monkeys using a modified flow cytometry method (FCM). The standard commercial human A or B-red blood cells (RBCs) were used as target cells. The binding of target cells and anti-A or B blood group Ab in sera of rhesus or cynomolgus monkeys was detected by flow cytometry after adding secondary specific fluorescence-labeled anti-human IgG or IgM Ab. Human healthy blood donor sera were used as controls. The results revealed that, using clear monkey sera, which were pre-absorbed on normal human type O RBCs to remove non-specific anti-human Abs, the modified FCM gave an accurate detection of ABO Ab levels in monkeys. When compared with the results of human sera, the distribution of ABO Ab levels in monkey sera were significantly lower (P<0.05). We concluded that the modified FCM could be used for the detection of monkey ABO Ab levels. The technique and data will be very valuable for the future establishment of ABO-incompatible organ transplant models in non-human primates, which could improve clinical applications.

A mixed-space approach to first-principles calculations of phonon frequencies for polar materials

We propose a mixed-space approach using the accurate force constants calculated by the direct approach in real space and the dipole-dipole interactions calculated by linear response theory in reciprocal space, making the accurate prediction of phonon frequencies for polar materials possible using the direct approach as well as linear response theory. As examples, by using the present approach, we predict the first-principles phonon properties of the polar materials α-Al(2)O(3), MgO, c-SiC, and h-BN, which are in excellent agreement with available experimental data.

Broadband external cavity tunable quantum dot lasers with low injection current density

Broadband grating-coupled external cavity laser, based on InAs/GaAs quantum dots, is achieved. The device has a wavelength tuning range from 1141.6 nm to 1251.7 nm under a low continuous-wave injection current density (458 A/cm(2)). The tunable bandwidth covers consecutively the light emissions from both the ground state and the 1st excited state of quantum dots. The effects of cavity length and antireflection facet coating on device performance are studied. It is shown that antireflection facet coating expands the tuning bandwidth up to ~150 nm, accompanied by an evident increase in threshold current density, which is attributed to the reduced interaction between the light field and the quantum dots in the active region of the device.

A clinical study of 115 patients with extranodal natural killer/T-cell lymphoma, nasal type

AIMS

To investigate the clinicopathological features, treatment outcomes, and prognostic factors in patients with extranodal natural killer (NK)/T-cell lymphoma, nasal type.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 115 patients diagnosed with extranodal NK/T-cell lymphoma, nasal type who were admitted to our hospital between January 1991 and June 2006.

RESULTS

In total, 107 patients were available for follow-up. After the completion of treatment, 48 patients (44.9%) achieved a complete remission. By the end of the follow-up period, 60 patients (56.1%) had died from local recurrence or metastases. The mean survival duration was 70.0 months, the median survival duration was 42 months, and the 5-year survival rate was 39.4%. The mean survival durations of the three treatment groups of chemoradiotherapy, radiotherapy and palliative treatment were 91.6, 60.1 and 17.6 months, respectively. The median survival durations were 72.0, 42.0 and 10 months, respectively. Patients treated with > 50 Gy had better local control and survival than the < 50 Gy group. However, there was no significant difference between patients having fewer than four cycles of chemotherapy and patients having more than four cycles. Multifactor Cox regression model analysis showed that B symptoms, gender, International Prognostic Index (IPI) score, disease stage and therapy were all independent prognostic factors.

CONCLUSIONS

The prognosis of extranodal NK/T-cell lymphoma, nasal type is poor and significantly influenced by B symptoms, gender, IPI score, clinical staging and the method of treatment. Chemoradiotherapy should be the first choice for treatment.

Prolonged cardiac allograft survival in presensitized rats after a high activity Yunnan-cobra venom factor therapy

Complement-dependent antibody-mediated acute humoral rejection is the major obstacle of clinical transplantation across ABO incompatibility and human leukocyte antigen presensitization. We previously demonstrated that Yunnan-cobra venom factor (Y-CVF) could almost completely abrogate complement activity and successfully prevent hyperacute rejection in some xenotransplant models without any obvious toxicity. In this study we investigated whether depletion of complement by Y-CVF prevented acute humoral allograft rejection in presensitized rats thereby prolonging graft survival.

METHODS

Presensitization was achieved in Lewis rats by sequential grafting of three full-thickness skin pieces from Brown Norway rats. Serum cytotoxic alloantibody titers were determined by a modified in vitro complement-dependent microcytotoxicity assay. After presensitization, each Lewis rat received a heterotopic Brown Norway cardiac allograft. Fifteen recipients were divided into two groups: (1) no treatment control (n = 7); (2) Y-CVF therapy group (86 u/kg, IV, day -1) (n = 8). After cessation of the heart beat, allograft rejection was confirmed by pathologic as well as IgG and C3 immunohistochemical examinations.

RESULTS

The mean graft survival time was significantly prolonged to 99.50 +/- 38.72 hours among rats that received Y-CVF vs 12.71 +/- 13.94 hours in nontreated controls (P < .001). Upon pathological and immunohistochemical examination, acute humoral rejection was mainly exhibited in the control group, whereas acute cellular rejection was mainly displayed in the Y-CVF therapy group.

CONCLUSIONS

Our study demonstrated that complement depletion by Y-CVF significantly inhibited acute humoral allograft rejection in presensitized rats. As a therapeutic immunointervention tool for complement, Y-CVF has shown potential efficacy across ABO incompatible and positive cross-match barriers.

Purification, characterization and cytokine release function of a novel Arg-49 phospholipase A(2) from the venom of Protobothrops mucrosquamatus

Group IIA phospholipase A(2) (PLA(2)) are major components in Viperidae/Crotalidae venom. In the present study, a novel PLA(2) named promutoxin with Arg at the site 49 has been purified from the venom of Protobothrops mucrosquamatus by chromatography. It consists of 122 amino acid residues with a molecular mass of 13,656 Da assessed by MALDI-TOF. It has the structural features of snake venom group IIA PLA(2)s, but has no PLA(2) enzymatic activity. Promutoxin shows higher amino acid sequence identity to the K49 PLA(2)s (72-95%) than to D49 PLA(2)s (52-58%). Promutoxin exhibits potent myotoxicity in the animal model with as little as 1 microg of promutoxin causing myonecrosis and myoedema in the gastrocnemius muscle of mice. Promutoxin is also able to stimulate the release of IL-12, TNFalpha, IL-6 and IL-1beta from human monocytes, and induce IL-2, TNFalpha and IL-6 release from T cells, indicating that this snake venom group IIA PLA(2) is actively involved in the inflammatory process in man caused by snake venom poisoning.

Factors influencing arsenic accumulation by Pteris vittata: a comparative field study at two sites

This study compared the factors influencing arsenic (As) accumulation by Pteris vittata at two sites, one containing As along with Au mineralization and the other containing Hg/Tl mineralization. The soils above these two sites contained high As concentrations (26.8-2955 mg kg(-1)). Although the As concentration, pH, soil cation exchange capacity and plant biomass differed significantly between the two sites, no differences were observed in the As concentrations in the fronds and roots, or the translocation factors, of P. vittata, suggesting that this species has consistent As hyperaccumulation properties in the field. The As concentration in the fronds was positively related to phosphorus (P) and potassium (K), but negatively related to calcium (Ca), at one site. This suggested that P, K and Ca influenced As accumulation by P. vittata in the field.

N49 phospholipase A2, a unique subgroup of snake venom group II phospholipase A2

A novel phospholipase A2 (PLA2) with Asn at its site 49 was purified from the snake venom of Protobothrops mucrosquamatus by using SP-Sephadex C25, Superdex 75, Heparin-Sepharose (FF) and HPLC reverse-phage C18 chromatography and designated as TM-N49. It showed a molecular mass of 13.875 kDa on MALDI-TOF. TM-N49 does not possess enzymatic, hemolytic and hemorrhagic activities. It fails to induce platelet aggregation by itself, and does not inhibit the platelet aggregation induced by ADP. However, it exhibits potent myotoxic activity causing inflammatory cell infiltration, severe myoedema, myonecrosis and myolysis in the gastrocnemius muscles of BALB/c mice. Phylogenetic analysis found that that TM-N49 combined with two phospholipase A2s from Trimeresurus stejnegeri, TsR6 and CTs-R6 cluster into one group. Structural and functional analysis indicated that these phospholipase A2s are distinct from the other subgroups (D49 PLA2, S49 PLA2 and K49 PLA2) and represent a unique subgroup of snake venom group II PLA2, named N49 PLA2 subgroup.

Potent histamine-releasing activity of atrahagin, a novel snake venom metalloproteinase

Poisonous snakebite wound is a popular disease worldwide. However, the pathogenesis remains unclear. In the present study, a novel metalloproteinase atrahagin in Chinese cobra (Naja atra) snake venom was purified, using heparin-sepharose followed by Superdex 75 gel filtration chromatography. Apart from its alpha-fibrinogenase activity, atrahagin potently activated human colon, lung and tonsil mast cells with the net histamine release being 25.9+/-4.4, 17.0+/-1.9, 13.2+/-3.6%, respectively. Time course studies revealed that the peak histamine release induced by atrahagin occurred at 12, 12 and 8 min following incubation of the enzyme with colon, lung and tonsil mast cells, respectively. The response of mast cells to atrahagin was abolished by preincubation of the cells with metabolic inhibitors or pertussis toxin, and by removal of Ca2+ and Mg2+ from the challenge buffer. In conclusion, activation of human mast cells by atrahagin indicated that the enzyme might contribute to the pathogenesis of snakebite wound.

Characterization and molecular cloning of dabocetin, a potent antiplatelet C-type lectin-like protein from Daboia russellii siamensis venom

A novel C-type lectin-like protein, dabocetin, was purified from Daboia russellii siamensis venom. On SDS-polyacrylamide gel electrophoresis, it showed a single band with an apparent molecular weight of 28 kDa and two distinct bands with the apparent molecular weights of 15.0 kDa and 14.5 kDa under non-reducing and reducing conditions, respectively. cDNA clones containing the coding sequences for dabocetin alpha and beta subunits were isolated and sequenced. The deduced protein sequences of both subunits were confirmed by N-terminal amino acid sequencing and trypsin-digested peptide mass fingerprinting. Dabocetin did not induce platelet aggregation in platelet-rich plasma. It also had little effect on the platelet aggregation induced by ADP, TMVA or stejnulxin. Whereas, dabocetin inhibited ristocetin-induced platelet agglutination in platelet-rich plasma in a dose-dependent manner with an IC50 value of 0.35 microM. Flow cytometry analysis showed that dabocetin significantly inhibited mAb SZ2 binding to platelet membrane glycoprotein Ib alpha, indicating that platelet membrane glycoprotein Ib is involved in the inhibitory effect of dabocetin on ristocetin-induced platelet agglutination.

Vascular endothelial growth factor and its receptor Flk-1 are expressed in the hippocampus following entorhinal deafferentation

Vascular endothelial growth factor (VEGF) has been thought of as a mitogen that promotes proliferation of endothelial cells and as a neurotrophic factor that stimulates neurogenesis and axonal growth in both peripheral and central nervous systems. To investigate the potential involvement of VEGF in the lesion-induced reorganization in the brain, the expression changes of VEGF and its receptor Flk-1 were analyzed in the mouse hippocampus after transections of the entorhinal afferents. In situ hybridization and immunohistochemistry showed the time-dependent expression upregulation of VEGF mRNA and protein in the entorhinally denervated hippocampal stratum lacunosum-moleculare and dentate outer molecular layer, which initiated by 3 days postlesion, reached its maximum at 7-15 days postlesion, still persisted by 30 days postlesion for protein, and recovered to the normal levels at 30 days postlesion for mRNA and at 60 days postlesion for protein. Double labeling of VEGF and glial fibrillary acidic protein revealed that VEGF-expressing cells in the denervated areas were reactive astrocytes. Semi-quantitative RT-PCR analysis showed that VEGF receptor Flk-1 mRNA was also time-dependently upregulated in the deafferented hippocampus with its maximal elevation at 7-15 days postlesion while the Flt-1 mRNA levels remained unchanged at any time point we examined. Immunohistochemistry analysis also displayed the upregulation of Flk-1 protein in the denervated stratum lacunosum-moleculare and outer molecular layer with a time course similar to that of VEGF mRNA upregulation. Flk-1 receptors were found to be expressed not only by reactive astrocytes but also by neurites, which most likely belong to sprouting axons by 7 days postlesion and regrowing dendrites by 15-30 days postlesion. From these data we suggest that the spatiotemporal upregulation of VEGF and Flk-1 in the hippocampus is induced by entorhinal deafferentation and that VEGF may be involved in the structural reorganization in the deafferented hippocampus via directly or indirectly promoting neurite growth.

Neuroprotective flavonoids from Flemingia macrophylla

Using an Abeta-induced neurotoxicity blocking assay to direct fractionation, three new flavonoids, fleminginin (1), flemingichromone (2), and flemingichalcone (3), and twenty known compounds were isolated from the active fractions of the aerial parts of Flemingia macrophylla. The structures of 1 - 3 were elucidated on the basis of spectroscopic data. When tested for neuroprotective activity, compound 2, osajin ( 4), 5,7,4'-trihydroxy-6,8-diprenylisoflavone (5), 5,7,4'-trihydroxy-6,3'-diprenylisoflavone (6), and aureole (7) protected neuronal cells from Abeta-induced damage with EC50 values of 31.43 +/- 3.16, 5.01 +/- 1.28, 11.25 +/-1.51, 4.47 +/- 0.65, 12.09 +/- 2.55 microM, respectively.

A novel disintegrin, jerdonatin, inhibits platelet aggregation and sperm-egg binding

A novel disintegrin, jerdonatin, was purified to homogeneity from Trimeresurus jerdonii venom by gel filtration and reversed-phase high-pressure liquid chromatography. We isolated the cDNA encoding jerdonatin from the snake venom gland. Jerdonatin cDNA precursor encoded pre-peptide, metalloprotease and disintegrin domain. Jerdonatin is composed of 72 amino acid residues including 12 cysteines and the tripeptide sequence Arg-Gly-Asp (RGD), a well-known characteristic of the disintegrin family. Molecular mass of jerdonatin was determined to be 8011 Da by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Jerdonatin inhibited ADP- and collagen-induced human platelet aggregation with IC50 of 123 and 135 nM, respectively. We also investigated the effect of jerdonatin on the binding of B6D2F1 hybrid mice spermatozoa to mice zona-free eggs and their subsequent fusion. Jerdonatin significantly inhibited sperm-egg binding in a concentration-dependent manner, but had no effect on the fusion of sperm-egg. These results indicate that integrins on the egg play a role in mammalian fertilization.

Purification, characterization and primary structure of a chymotrypsin inhibitor from Naja atra venom

A chymotrypsin inhibitor, designated NA-CI, was isolated from the venom of the Chinese cobra Naja atra by three-step chromatography. It inhibited bovine alpha-chymotrypsin with a Ki of 25 nM. The molecular mass of NA-CI was determined to be 6403.8 Da by matrix-assisted laser-desorption ionization time-of-flight (MALDI-TOF) analysis. The complete amino acid sequence was determined after digestion of S-carboxymethylated inhibitor with Staphylococcus aureus V8 protease and porcine trypsin. NA-CI was a single polypeptide chain composed of 57 amino acid residues. The main contact site with the protease (P1) has a Phe, showing the specificity of the inhibitor. NA-CI shared great similarity with the chymotrypsin inhibitor from Naja naja venom (identities=89.5%) and other snake venom protease inhibitors.

TMVA, a novel GPIb-binding protein, significantly prevents platelet microthrombi formation and prolongs discordant cardiac xenograft survival

In xenotransplantation, donor endothelium is the first target of immunological attack. Activation of the endothelial cell by preformed natural antibodies leads to platelet binding via the interaction of the glycoprotein (GP) Ib and von Willebrand factor (vWF). TMVA is a novel GPIb-binding protein purified from the venom of Trimeresurus mucrosquamatus. In this study, the inhibitory effect of TMVA on platelet aggregation in rats and the effect on discordant guinea pig-to-rat cardiac xenograft survival were investigated. Three doses (8, 20 or 40 microg/kg) of TMVA were infused intravenously to 30 rats respectively. Platelet aggregation rate was assayed 0.5, 12, and 24 h after TMVA administration. Wister rats underwent guinea pig cardiac cervical heterotopic transplantation using single dosing of TMVA (20 microg/kg, i.v., 0.5 h before reperfusion). Additionally, levels of TXB(2) and 6-keto-PGF(1alpha) within rejected graft tissues were determined by radioimmunoassay. Treatment with TMVA at a dose of 20 or 40 microg/kg resulted in complete inhibition of platelet aggregation 0.5 h after TMVA administration. Rats receiving guinea pig cardiac xenografts after TMVA therapy had significantly prolonged xenograft survival. Histologic and immunopathologic analysis of cardiac xenografts in TMVA treatment group showed no intragraft platelet microthrombi formation and fibrin deposition. Additionally, the ratio of 6-keto-PGF(1alpha) to TXB(2) in TMVA treatment group was significantly higher than those in control group. We conclude that the use of this novel GPIb-binding protein was very effective in preventing platelet microthrombi formation and fibrin deposition in a guinea pig-to-rat model and resulted in prolongation of xenograft survival. The increased ratio of PGI(2)/TXA(2) in TMVA treatment group may protect xenografts from the endothelial cell activation and contribute to the prolongation of xenograft survival.

TMVA, a snake C-type lectin-like protein from Trimeresurus mucrosquamatus venom, activates platelet via GPIb

TMVA is a C-type lectin-like protein with potent platelet activating activity from Trimeresurus mucrosquamatus venom. In the absence of von Willebrand factor (vWF), TMVA dose-dependently induced aggregation of washed platelets. Anti-GP Ib monoclonal antibodies (mAbs), HIP1, specifically inhibited TMVA-induced aggregation in a dose-dependent manner. The aggregation was also inhibited by mAb P2 (an anti-GP IIb mAb). Flow cytometric analysis revealed that FITC-TMVA bound to human formalin-fixed platelets in a saturable manner, and its binding was specifically blocked by HIP1 in a dose-dependent manner. Flow cytometric analysis showed that TMVA did not bind to platelet GPIX, GPIIb, GPIIIa, GPIa, GPIIa and GPIV. Moreover, the platelet aggregation induced by TMVA was partially inhibited when platelet was pretreated with mocarhagin, a snake venom protease that specifically cleaves human GPIb. These results suggest that TMVA is a strong platelet agonist via GPIb and it might have multiple functional binding-sites on GPIb molecule or on other unknown receptor.

A novel high molecular weight metalloproteinase cleaves fragment F1 of activated human prothrombin

A hemorrhagic proteinase, jerdohagin, was purified from Trimeresurus jerdonii venom by gel filtration and ion-exchange chromatographies. It was a single chain polypeptide with an apparent molecular weight of 96 kDa as estimated by SDS-PAGE under the non-reducing and reducing conditions. Internal peptide sequencing indicated that it consisted of metalloproteinase, disintegrin-like and cysteine-rich domains and belonged to the class III snake venom metalloproteinases (class P-III SVMPs). Like other typical metalloproteinases, hemorrhagic activities of jerdohagin were completely inhibited by EDTA, but not by PMSF. Jerdohagin preferentially degraded alpha-chain of human fibrinogen. Interestingly, jerdohagin did not activate human prothrombin, whereas it cleaved human prothrombin and fragment F1 of activated human prothrombin.

Improved suppression of circulating complement does not block acute vascular rejection of pig-to-rhesus monkey cardiac transplants

At present, acute vascular rejection (AVR) remains a primary obstacle inhibiting long-term graft survival in the pig-to-non-human primate transplant model. The present study was undertaken to determine whether repetitive injection of low dose Yunnan-cobra venom factor (Y-CVF), a potent complement inhibitor derived from the venom of Naja kaouthia can completely abrogate hemolytic complement activity and subsequently improve the results in a pig-to-rhesus monkey heterotopic heart transplant model. Nine adult rhesus monkeys received a heterotopic heart transplant from wild-type pigs and the recipients were allocated into two groups: group 1 (n = 4) received repetitive injection of low dose Y-CVF until the end of the study and group 2 (n = 5) did not receive Y-CVF. All recipients were treated with cyclosporine A (CsA), cyclophosphamide (CyP) and steroids. Repetitive Y-CVF treatment led to very dramatic fall in CH50 and serum C3 levels (CH50 < 3 units/C3 remained undetectable throughout the experiment) and successfully prevented hyperacute rejection (HAR), while three of five animals in group 2 underwent HAR. However, the continuous suppression of circulating complement did not prevent AVR and the grafts in group 1 survived from 8 to 13 days. Despite undetectable C3 in circulating blood, C3 deposition was present in these grafts. The venular thrombosis was the predominant histopathologic feature of AVR. We conclude that repetitive injection of low dose Y-CVF can be used to continuously suppress circulating complement in a very potent manner and successfully prevent HAR. However, this therapy did not inhibit complement deposition in the graft and failed to prevent AVR. These data suggest that using alternative pig donors [i.e. human decay accelerating factor (hDAF)-transgenic] in combination with the systemic use of complement inhibitors may be necessary to further control complement activation and improve survival in pig-to-non-human primate xenotransplant model.

Purification, cloning and biological characterization of a novel disintegrin from Trimeresurus jerdonii venom

A novel disintegrin, jerdonin, was purified from the Trimeresurus jerdonii venom by means of gel filtration and reverse phase high pressure liquid chromatography. Its coding cDNA was also isolated from the venom gland. The jerdonin coding cDNA is part of a precursor composed of proprotein, metalloproteinase, and disintegrin domains. From the deduced amino acid sequence, jerdonin is composed of 71 amino acid residues including 12 cysteines and the tripeptide sequence Arg-Gly-Asp (RGD), a well-known characteristic of the disintegrin family. Molecular mass of jerdonin was determined to be 7483Da by matrix-assisted laser desorption ionization time of flight mass spectrometry. Jerdonin inhibited ADP- and collagen-induced human platelet aggregation with IC(50) of 220 and 240 nM, respectively. In vivo, jerdonin inhibited the growth of subcutaneously inoculated B16 solid tumor in C57BL/6 mice and improved the survival time of the tumor-bearing mice.

A new protein structure of P-II class snake venom metalloproteinases: it comprises metalloproteinase and disintegrin domains

A new metalloproteinase-disintegrin, named Jerdonitin, was purified from Trimeresurus jerdonii venom with a molecular weight of 36 kDa on SDS-PAGE. It dose-dependently inhibited ADP-induced human platelet aggregation with IC(50) of 120nM. cDNA cloning and sequencing revealed that Jerdonitin belonged to the class II of snake venom metalloproteinases (SVMPs) (P-II class). Different from other P-II class SVMPs, metalloproteinase and disintegrin domains of its natural protein were not separated, confirmed by internal peptide sequencing. Compared to other P-II class SVMPs, Jerdonitin has two additional cysteines (Cys219 and Cys238) located in the spacer domain and disintegrin domain, respectively. They probably form a disulfide bond and therefore the metalloproteinase and disintegrin domains cannot be separated by posttranslationally processing. In summary, comparison of the amino acid sequences of Jerdonitin with those of other P-II class SVMPs by sequence alignment and phylogenetic analysis, in conjunction with natural protein structure data, suggested that it was a new type of P-II class SVMPs.

Prolonged cardiac xenograft survival in guinea pig-to-rat model by a highly active cobra venom factor

A highly active cobra venom factor (CVF) was isolated from the venom of Naja kaouthia by sequential column chromatography. It displays strong anticomplementary activity, and has 1515 U of anticomplementary activity per mg protein. A single dose of 0.1 mg/kg CVF given i.v. to rats completely abrogated complement activity for nearly 5 days. Given 0.02 mg/kg of CVF, the complement activity of rats was reduced by more than 96.5% in 6 h. In guinea pig-to-rat heart transplant model, rats treated with a single dose of 0.05 mg/kg CVF had significantly prolonged xenograft survival (56.12+/-6.27 h in CVF-treated rats vs. 0.19+/-0.07 h in control rats, P<0.001).

Jerdonase, a novel serine protease with kinin-releasing and fibrinogenolytic activity from Trimeresurus jerdonii venom

A novel kinin-releasing and fibrin(ogen)olytic enzyme termed jerdonase was purified to homogeneity from the venom of Trimeresurus jerdonii by DEAE Sephadex A-50 anion exchange, Sephadex G-100 (superfine) gel filtration and reverse-phase high performance liquid chromatography (RP-HPLC). Jerdonase migrated as a single band with an approximate molecular weight of 55 kD under the reduced conditions and 53 kD under the non-reduced conditions. The enzyme was a glycoprotein containing 35.8% neutral carbohydrate. The N-terminal amino acid sequence of jerdonase was determined to be IIGGDECNINEHPFLVALYDA, which showed high sequence identity to other snake venom serine proteases. Jerdonase catalyzed the hydrolysis of BAEE, S-2238 and S-2302, which was inhibited by phenylmethylsulfonyl fluoride (PMSF), but not affected by ethylenediaminetetraacetic acid (EDTA). Jerdonase preferentially cleaved the A alpha-chain of human fibrinogen with lower activity towards B beta-chain. Moreover, the enzyme hydrolyzed bovine low-molecular-mass kininogen and releasing bradykinin. In conclusion, all results indicated that jerdonase was a multifunctional venom serine protease.

In vitro activities of small peptides from snake venom against clinical isolates of drug-resistant Mycobacterium tuberculosis

The recent re-emergence of tuberculosis, especially the multidrug-resistant cases, has highlighted the importance of screening effective novel drugs against Mycobacterium tuberculosis. In this study, the in vitro activities of small peptides isolated from snake venom were investigated against multidrug-resistant M. tuberculosis. Minimum inhibitory concentrations (MICs) were determined by the Bactec TB-460 radiometric method. A small peptide with the amino acid sequence ECYRKSDIVTCEPWQKFCYREVTFFPNHPVYLSGCASECTETNSKWCCTTDKCNRARGG (designated as vgf-1) from Naja atra (isolated from Yunnan province of China) venom had in vitro activity against clinically isolated multidrug-resistant strains of M. tuberculosis. The MIC was 8.5 mg/l. The antimycobacterial domain of this 60aa peptide is under investigation.

Alpha-neurotoxins of Naja atra and Naja kaouthia snakes in different regions

Recent studies have shown that there are geographic variation of alpha-neurotoxins in Naja kaouthia, but the cause is not clear yet. In this work, venoms were collected from adult Naja atra in Zhejiang Province and Naja kaouthia in Yunnan Province, well identified by morphological characters and cytochrome b gene analysis in summer season to avoid age and seasonal variation in the venom composition. Then alpha-neurotoxins were purified and cloned from these two kinds of snakes. Three alpha-neurotoxins from Naja kaouthia (Yunnan) and two from Naja atra (Zhejiang) were identified. Together with previously reported alpha-neurotoxins in Naja kaouthia (Thailand) and Naja atra (Taiwan Province), it was found that the alpha-neurotoxins of Naja kaouthia in Yunnan Province were similar to those of Naja atra in Zhejiang and Taiwan Provinces, but different from those of Naja kaouthia in Thailand. This result can hardly be explained by population phylogeny or geographic distance. It might be due to the different climate, habitat and prey in Thailand in comparison with those in Yunnan, Zhejiang and Taiwan Provinces.

Characterization of a new bradykinin-potentiating peptide (TmF) from Trimeresurus mucrosquamatus

A novel bradykinin-potentiating peptide (BPP), designated as TmF, has been purified to homogeneity from the venom of Trimeresurus mucrosquamatus by 70% cold methanol extraction, Sephadex G-15 gel filtration and reverse-phase high performance liquid chromatography (RP-HPLC). The amino acid sequence of TmF was determined to be pGlu-Gly-Arg-Pro-Leu-Gly-Pro-Pro-Ile-Pro-Pro (pGlu denotes pyroglutamic acid), which shared high homology with other BPPs. The molecular mass of TmF was 1.1107 kD as determinated by electrospray ionization-mass spectrometry (ESI-MS), which was in accordance with the calculated value of 1.1106 kD. The potentiating unit of TmF to bradykinin-induced (BK-induced) contraction on the guinea-pig ileum in vitro was (1.13 +/-0.3) unit (mg/L), and TmF (5.0 x10(-4) mg/kg) increased the pressure-lowering-effect of bradykinin (5.0 x10(-5 )mg/kg) with approximate descent value of (14 +/-2) mmHg. In addition, TmF inhibited the conversion of angiotensin I to angiotensin II, 2 x10(-3) mg of TmF caused 50% inhibition (IC(50)) of angiotensin- converting enzyme (ACE) hydrolyzing activity to bradykinin.

Purification, characterization and biological activity of an L-amino acid oxidase from Trimeresurus mucrosquamatus venom

An L-amino acid oxidase (TM-LAO) from the venom of Hunan Trimeresurus mucrosquamatus was purified to homogeneity by three steps including DEAE Sephadex A-50 ion-exchange chromatography, Sephadex G-75 gel filtration and Resource Q ion-exchange chromatography. TM-LAO is composed of two identical subunits with a molecular weight of 55 kD by SDS-polyacrylamide gel electrophoresis. The molecular weight was different with that of LAO purified from the same species distributed in Taiwan that was 70 kD. The 24 N-terminal amino acid sequence of TM-LAO is ADNKNPLEECFRETNYEEFLEIAR, which shares high similarity with other Viperid snake venom LAOs and has moderate similarity with Elapid snake venom LAOs. Further studies found that TM-LAO inhibited the growth of E. coli, S. aurues and B. dysenteriae. TM-LAO also showed cytotoxicity and platelet aggregation activity. All the biological activities were eliminated by catalase, a H(2)O(2) scavenger. It was shown that these biological effects were possibly due to the formation of H(2)O(2) produced by TM-LAO.

L-amino acid oxidase from Trimeresurus jerdonii snake venom: purification, characterization, platelet aggregation-inducing and antibacterial effects

An L-amino acid oxidase (LAO), designated as TJ-LAO, was purified to homogeneity from the venom of Trimeresurus jerdonii by Sephadex G-100 and Q Sepharose HP chromatography. The molecular weight of this enzyme was 110 kD as estimated by analytical gel filtration and was 55 kD by SDS-polyacrylamide gel electrophoresis, suggesting that the enzyme is composed of two subunits. The enzyme has an absorption spectrum characteristic of flavoproteins, containing 2 moles of FMN per mole of enzyme. The N-terminal sequence of TJ-LAO shares high homology with other viperid snake venom LAOs. Homology with elapid venom LAO is lower. TJ-LAO inhibited the growth of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus megaterium. The antibacterial effect associated with LAO activity was elminated with the addition of catalase. Platelets in platelet-rich plasma aggregated upon the addition of TJ-LAO. The enzyme-induced aggregation was inhibited by catalase, suggesting formation of H2O2 was essential for TJ-LAO to induce platelet aggregation. These results showed H2O2 formation is important for the biological effects of LAO.

Purification and cloning of a novel C-type lectin-like protein with platelet aggregation activity from Trimeresurus mucrosquamatus venom

TMVA, a novel C-type lectin-like protein that induces platelet aggregation in a dose-dependent manner, was purified from the venom of Trimeresurus mucrosquamatus. It consists of two subunits, alpha (15536 Da) and beta (14873 Da). The mature amino acid sequences of the alpha (135 amino acids) and beta subunits (123 amino acids) were deduced from cloned cDNAs. Both of the sequences show great similarity to C-type lectin-like venom proteins, including a carbohydrate recognition domain. The cysteine residues of TMVA are conserved at positions corresponding to those of flavocetin-A and convulxin, including the additional Cys135 in the alpha subunit and Cys3 in the beta subunit. SDS-PAGE, mass spectrometry analysis and amino acid sequence showed that native TMVA exists as two convertible multimers of (alpha beta)(2) and (alpha beta)(4) with molecular weights of 63680 and 128518 Da, respectively. The (alpha beta)(2) complex is stabilized by an interchain disulfide bridge between the two alpha beta-heterodimers, whereas the stabilization of the (alpha beta)(4) complex seems to involve non-covalent interactions between the (alpha beta)(2) complexes.