Calf deep veins are safe and feasible accesses for the endovascular treatment of acute lower extremity deep vein thrombosis.

This study was designed to assess the optimal access route for the endovascular treatment of acute lower extremity deep vein thrombosis. This was a retrospective analysis of patients with acute lower extremity deep venous thrombosis who underwent endovascular treatment from February 2009 to December 2020. Patients underwent non-direct calf deep vein puncture (NDCDVP) from February 2009 to December 2011 and direct calf deep vein puncture (DCDVP) from January 2012 to December 2020. Catheter directed thrombolysis (CDT) was used to treat all patients in the NDCDVP group, whereas patients in the DCDVP group were treated with CDT or the AngioJet rhyolitic thrombectomy system. In patients exhibiting iliac vein compression syndrome, the iliac vein was dilated and implanted with a stent. Technical success rates and perioperative complication rates were compared between these two treatment groups. The NDCDVP group included 83 patients (40 males, 43 females) with a mean age of 55 ± 16 years, while the DCDVP group included 487 patients (231 males. 256 females) with a mean age of 56 ± 15 years. No significant differences were observed between these groups with respect to any analyzed clinical characteristics. The technical success rates in the NDCDVP and DCDVP groups were 96.4 and 98.2%, respectively (P > 0.05). In the NDCDVP group, the small saphenous vein (SSV)or great saphenous vein (GSV)were the most common access routes (77.1%, 64/83), whereas the anterior tibial vein (ATV) was the most common access route in the DCDVP group (78.0%, 380/487), followed by the posterior tibial vein (PTV) and peroneal vein (PV)(15.6% and 6.4%, respectively). Relative to the NDCDVP group, more patients in the DCDVP group underwent the removal of deep vein clots below the knee (7.2% [6/83] vs. 24.2% [118/487], P < 0.001). Moreover, relative to the NDCDVP group, significantly lower complication rates were evident in the DCDVP group (local infection: 10.8% vs. 0.4%, P < 0.001; local hematoma: 15.7% vs. 1.0%, P < 0.001). The position change rate was also significantly lower in the DCDVP group relative to the NDCDVP group (0% [0/487] vs. 60.2% [50/83], P < 0.001). The calf deep veins (CDVs) represent a feasible and safe access route for the endovascular treatment of lower extremity deep vein thrombosis.

A Retrospective Study Comparing Pharmacomechanical Thrombectomy with Catheter-Directed Thrombolysis for Acute Deep Venous Thrombosis.

BACKGROUND: This study aims to conduct a comparative analysis of the clinical efficacy and safety between pharmacomechanical thrombectomy (PMT) and catheter-directed thrombolysis (CDT) in the context of acute lower-extremity deep venous thrombosis (LEDVT). METHODS: A retrospective review of our institution's patient database spanning from February 2011 to December 2019 was performed to identify cases of acute LEDVT. The patients were categorized into 2 distinct groups based on the thrombolytic interventions administered: the PMT group, specifically denoting PMT with AngioJet in our investigation, and the CDT group. Comprehensive data sets encompassing patient demographics, risk factors, procedural specifics, thrombolysis grading, and complications were collected. Subsequent follow-up evaluations at the 2-year mark posttreatment included assessments of postthrombotic syndrome (PTS) and the quality of life. RESULTS: Among the 348 patients identified (mean age: 50.12 ± 15.87 years; 194 females), 200 underwent CDT during the early stage (2011 to 2017), while 148 received PMT between 2017 and 2019. Baseline data between the 2 groups exhibited no statistically significant differences. Thrombus scores significantly decreased in both cohorts posttherapy (each P < 0.001).Patients subjected to PMT demonstrated higher thrombolysis rates (77.35 ± 9.44% vs. 50.85 ± 6.72%), reduced administration of the thrombolytic agent urokinase [20 (20€20) vs. 350 (263€416), P < 0.001], larger limb circumference differences (above the knee: 6.03 ± 1.76 cm vs. 4.51 ± 1.82 cm, P < 0.001; below the knee: 2.90 ± 1.16 cm vs. 2.51 ± 0.90 cm, P < 0.001), and shorter lengths of stay (7.19 ± 3.11 days vs. 12.33 ± 4.77 days, P < 0.001). However, the PMT group exhibited a higher decline in hemoglobin levels (13.41 ± 10.59 g/L vs. 10.88 ± 11.41 g/L, P = 0.038) and an increase in creatinine levels [9.58 (2.32€15.82) umol/L vs. 4.53 (2.87€6.08) umol/L, P < 0.001] compared to the CDT group. No statistically significant differences were observed in the numbers of balloon angioplasty, stent implantation (each P > 0.050), and minor and major complications between the 2 groups. At the 1-year follow-up, PTS occurred in 13.51% of the PMT group compared to 26% of the CDT group (P = 0.025), with a higher incidence of moderate-severe PTS in the CDT group (8% vs. 2.7%, P = 0.036). At the 2-year follow-up, PTS was observed in 16.2% of the PMT group and 31.5% in the CDT group, P = 0.004. Preoperative and postoperative D-values of 36-Item Short Form Health Survey (SF-36) Physical Component Summary and SF-36 Mental Component Summary showed no statistically significant between-group differences. CONCLUSIONS: In our institutional experience, both PMT and CDT have proven to be effective and safe therapeutic approaches for managing acute LEDVT. PMT, in particular, demonstrated superior efficacy in achieving thrombosis resolution and mitigating the risk of PTS, affirming its role as a favorable intervention in this clinical context.

Gastrointestinal syndrome encountered during a train voyage to high altitudes: A 14-day survey of 69 passengers in China.

BACKGROUND: The diagnosis and evaluation of the severity of acute mountain sickness (AMS) continue to be problematic due to a lack of consensus on the inclusion of symptoms in a scoring system. Recent investigations highlight the significance of gastrointestinal symptoms in identifying this condition. However, the specific gastrointestinal symptoms associated with AMS have not been thoroughly elucidated in previous studies, and the underlying risk factors remain inadequately comprehended. METHODS: This study aimed to investigate the characteristics, trends, and risk factors related to gastrointestinal symptoms encountered during train travel to high altitude. A total of 69 passengers, specifically all with medical backgrounds, were surveyed 6 times over a period of 14 days. RESULTS: The daily incidence of abdominal discomfort was higher than non-gastrointestinal symptoms within 14 days. Gastrointestinal symptoms demonstrated a greater prevalence, longer duration, and increased risk compared to non-gastrointestinal symptoms, such as headaches. The symptoms of abdominal distension and bowel sound hyperaction were found to be prevalent and persistent among patients diagnosed with AMS, exhibiting a high incidence rate. Gender, age, body mass index (BMI), smoking habits, and alcohol consumption were identified as risk factors associated with the occurrence and duration of gastrointestinal symptoms. CONCLUSION: This study suggests that gastrointestinal symptoms are more common and persistent when traveling to the plateau by train. These symptoms should be taken into consideration in the further diagnosis and prevention of AMS. Therefore, this study provides a significant theoretical foundation for the prevention and treatment of AMS.

Enteric glial cells aggravate the intestinal epithelial barrier damage by secreting S100ß under high-altitude conditions.

Damage to the intestinal epithelial barrier (IEB) has been reported under high-altitude (HA) conditions and may be responsible for HA-associated gastrointestinal (GI) disorders. However, this pathogenetic mechanism does not fully explain the GI stress symptoms, such as flatulence and motility diarrhea, which accompany the IEB damage under HA conditions, especially for the people exposed to HA acutely. In the present study, we collected the blood samples from the people who lived at HA and found the concentration of enteric glial cells (EGCs)-associated biomarkers increased significantly. HA mouse model was then established and the results revealed that EGCs were involved in IEB damage. Zona occludens (ZO)-1, occludin, and claudin-1 expression was negatively correlated with that of glial fibrillary acidic protein (GFAP) and S100ß under HA conditions. In order to learn more about how EGCs influence IEB, the in vitro EGC and MODE-K hypoxia experiments that used hypoxic stimulation for simulating in vivo exposure to HA was performed. We found that hypoxia increased S100ß secretion in EGCs. And MODE-K cells cultured in medium conditioned by hypoxic EGCs showed low ZO-1, occludin, and claudin-1 levels of expression. Furthermore, treatment of MODE-K cells with recombinant mouse S100ß resulted in diminished levels of ZO-1, occludin, and claudin-1 expression. Thus, HA exposure induces greater S100ß secretion by EGCs, which aggravates the damage to the IEB. This study has revealed a novel mechanism of IEB damage under HA conditions, and suggest that EGCs may constitute a fresh avenue for the avoidance of GI disorders at HA.

Inhibition of sediment erosion and phosphorus release by remediation strategy of contaminated sediment backfilling.

The management of sediment-water interfaces, especially bed stability, is essential for controlling accumulated contaminants in the sediment. In this study, the relationship between sediment erosion and phosphorus (P) release under the remediation strategy of contaminated sediment backfilling (CSBT) was explored through a flume experiment, i.e. the dredged sediment was calcined into ceramsite after dewatering and detoxification and then backfilled to the dredged area for sediment capping, thus avoiding the introduction of foreign materials via in-situ remediation and the large-scale land occupation associated with ex-situ remediation. Acoustic Doppler velocimeter (ADV) and optical backscatter sensor (OBS) were used to measure the vertical distributions of flow velocity and sediment concentration in the overlying water, respectively, and diffusive gradients in thin films (DGT) was used to measure the P distribution in the sediment. The results revealed that improving bed stability from CSBT can considerably improve the robustness of sediment-water interface and reduce sediment erosion by more than 70%. The corresponding P release from the contaminated sediment could be inhibited with an inhibition efficiency as high as 80%. CSBT is a potent strategy for managing contaminated sediment. This study provides a theoretical reference for controlling sediment pollution, further supporting river and lake ecological management and environmental restoration.

The external jugular vein is a feasible and safe alternative access for retrieval of inferior vena cava filter.

PURPOSE: The purpose is to analyze whether the external jugular vein (EJV) is a feasible and safe alternative access for the retrieval IVCFs designed for the jugular approach. METHODS: This study was designed as a nonrandomized, controlled study. The patients were divided into two groups: the IJV or EJV access groups. All operations were performed by the vascular surgery team. The main outcome was the technical success rate. The secondary outcomes included (1) the IVCF retrieval rate; (2) the time required to puncture the access vein (min); (3) the number of punctures required for access, and other aspects. RESULTS: A total of 119 patients were recruited for IVCF retrieval. Seventeen patients refused to join this trial, leaving 58 patients in the IJV group and 44 patients in the EJV group. In the IJV group, technical success was not achieved in one patient who started in the EJV group and was transferred to the IJV group. There was no significant difference in age, comorbidities, or technical success rate between the two groups. Significant differences were observed in puncture time (min), number of punctures, and inadvertent puncture of the carotid artery. All of the patients were discharged 1 or 2 days after the operation. CONCLUSION: EJV is safe and feasible alternative access for the retrieval of IVCFs that are designed for jugular approaches.

Dynamic Changes in Coagulation Function in Patients With Pneumonia Under Admission and Non-admission Treatment.

Objective: We aimed to explore the dynamic changes in coagulation function and the effect of age on coagulation function in patients with pneumonia under admission and non-admission treatment. Methods: We included 178 confirmed adult inpatients with COVID-19 from Wuhan Union Hospital Affiliated to Huazhong University of Science and Technology (Wuhan, China). Patients were classified into common types, and all were cured and discharged after hospitalization. We recorded the time of the first clinical symptoms of the patients and performed blood coagulation tests at the time of admission and after admission. In total, eight factors (TT, FIB, INR, APTT, PT, DD, ATIII, and FDP) were analyzed. Patients were classified into four groups according to the time from the first symptom onset to hospital admission for comparative analysis. The patients who were admitted within 2 weeks of disease onset were analyzed for the dynamic changes in their blood coagulation tests. Further division into two groups, one group comprising patients admitted to the hospital within 2 weeks after the onset of disease and the other comprising patients admitted to the hospital 2 weeks after disease onset, was performed to form two groups based on whether the patient ages were over or under 55 years. Chi-square tests and T tests were used to explore the dynamic changes in coagulation function and the influence of age on the results of coagulation function tests. Results: A total of 178 inpatients, 34 of whom underwent dynamic detection, were included in this analysis. We divided these patients into four groups according to the interval between the onset of COVID-19 pneumonia and the time to admission in the hospital: the 1-7 days (group 1), 8-14 days (group 2), 15-21 days (group 3), and >21-days (group 4). Eight factors all increased within 2 weeks after onset and gradually decreased to normal 2 weeks before the patient was admitted. The changes in coagulation function of patients admitted to the hospital were similar. After being admitted to the hospital, the most significant decreases among the eight factors were between week 2 and 3. There were distinct differences among the eight factors between people older than 55 years and those younger than 55 years. In the first 2 weeks after being admitted, the levels of the eight factors in patients >55 years were significantly higher than those in patients <55 years, and after another 2 weeks of treatment, the factor levels in both age groups returned to normal. Conclusion: The eight factors all increased within 2 weeks after onset and gradually decreased to normal after 2 weeks regardless of treatment. Compared with patients younger than 55 years, patients older than 55 years have greater changes in their blood coagulation test values.

[Regulation Control of a Tribasic Amendment on the Chemical Fractions of Cd and As in Paddy Soil and Their Accumulation in Rice].

A pot experiment was conducted to identify the effect of a tribasic amendment (limestone+diatomite+ferric sulfate, LDF) on chemical fractions of Cd and As in paddy soils and their accumulation in brown rice. LDF was set to seven levels (0, 0.5, 1.0, 2.0, 4.0, 8.0, and 16.0 g·kg-1) based on the quality ratio, and two genotypes of rice were planted (Huanghuazhan and T-you 272). The results show that:① The application of LDF increased the rhizosphere soil pH of two varieties of rice, Huanghuazhan and T-you 272, by 0.01-0.42 and 0.11-0.54, respectively, and decreased the concentrations of EX-Cd by 11.1%-61.1% and 26.5%-52.9%, respectively, and the concentrations of EX-As by 8.2%-60.0% and 5.6%-49.9%, respectively. ② Application of LDF promoted the transformation of soil Cd and As from soluble to insoluble forms. Although the trends of the rhizosphere soils of the two rice varieties were not consistent, the application of LDF could decrease the proportion of EX-Cd and increase the proportion of Fe/Mn-Cd, Org-Cd, and O-Cd, which was accompanied by the reduction of the proportion of EX-As and an increase in the proportion of Ca-As. ③ The concentrations of Cd, As, and Fe in the iron plaque decreased by applying LDF, while the concentration of Mn increased, and the maximum increase of Mn could reach 124.2%. ④ Application of LDF decreased the concentrations of Cd in brown rice of the two varieties of rice by 64.6% and 65.9%, respectively, and decreased that of As by 37.0% and 42.5%, respectively. The effect on the concentrations of inorganic As was not significant. When the application amount of LDF was 2-16 g·kg-1, the concentrations of Cd and inorganic As in T-you 272 brown rice were both under 0.2 mg·kg-1, and when the application amount was 16 g·kg-1, the concentrations of Cd and inorganic As in Huanghuazhan brown rice were both under 0.2 mg·kg-1. In actual agricultural production, the application amount of LDF can be adjusted according to the soil pollution levels and the rice varieties.

Flexible Electrode by Hydrographic Printing for Surface Electromyography Monitoring.

Surface electromyography (sEMG) monitoring has recently inspired new applications in the field of patient diagnose, rehabilitation therapy, man-machine-interface and prosthesis control. However, conventional wet electrodes for sEMG recording cannot fully satisfy the requirements of these applications because they are based on rigid metals and conductive gels that cause signal quality attenuation, motion artifact and skin allergy. In this study, a novel flexible dry electrode is presented for sEMG monitoring. The electrode is fabricated by screen-printing a silver-eutectic gallium-indium system over a transfer tattoo paper, which is then hydrographically printed on 3D surface or human skin. Peano curve in open-network pattern is adopted to enhance the mechanics of the electrode. Hydrographic printing enables the electrode to attach to skin intimately and conformably, meanwhile assures better mechanical and electrical properties and therefore improves the signal quality and long-term wearability of the electrode. By recording sEMG signal of biceps under three kinds of movement with comparison to conventional wet electrode, the feasibility of the presented flexible dry electrode for sEMG monitoring was proved.

Synthesis of (ZrO2-Al2O3)/GO nanocomposite by sonochemical method and the mechanism analysis of its high defluoridation.

A nanocomposite of (ZrO2-Al2O3)/GO was successfully synthesized by a simple sonochemical method in this study. A special 3D network was formed in (ZrO2-Al2O3)/GO, which produced a large surface area and good distribution of metal oxide nanoparticles. The as-synthesized (ZrO2-Al2O3)/GO exhibits a maximum fluoride adsorption capacity of 62.2 mg/g, and an adsorption ability of 13.80 mg/g when the F- equilibrium concentration is 1 mg/L, both of which are higher than most previously reported defluoridation adsorbents, indicating that it is among the top adsorbents. Large amounts of drinking water contaminated by F- can be treated by (ZrO2-Al2O3)/GO to meet the WHO limit, indicating the high potential for practical application of the adsorbent. Based on the experimental analysis, the origin of the high defluoridation performance and the adsorption mechanism were discussed in detail. Due to the simple preparation, easy operation and high performance, the adsorbent and the related sonochemical method are considered to be significant for developing highly effective adsorbents.

Multiple doping structures of the rare-earth atoms in ß-SiAlON:Ce phosphors and their effects on luminescence properties.

The critical doping structures of rare-earth atoms in the promising ß-SiAlON phosphors have long been argued owing to the lack of direct evidence. Here, the exact locations and coordination of the Ce rare-earth atoms in the ß-SiAlON structure have been examined using an atom-resolved Cs-corrected scanning transmission electron microscope. Three different occupation sites for the Ce atoms have been directly observed: two of them are in the structural channel coordinated with six and nine N(O) atoms, respectively; the other one is the unexpected substitution site for Si(Al). The chemical valences and stabilities of the doping Ce ions at the different occupation sites have been evaluated using density functional calculations. Correlation of the different doping structures with the luminescence properties has been investigated by the aid of cathodoluminescence (CL) microanalysis, which verifies the different contribution of the interstitial trivalent Ce ions to the light emission while no luminescence is observed for the substitutional doping of quadrivalent Ce.

Structural and Functional Diversity of Peptide Toxins from Tarantula Haplopelma hainanum (Ornithoctonus hainana) Venom Revealed by Transcriptomic, Peptidomic, and Patch Clamp Approaches.

Spider venom is a complex mixture of bioactive peptides to subdue their prey. Early estimates suggested that over 400 venom peptides are produced per species. In order to investigate the mechanisms responsible for this impressive diversity, transcriptomics based on second generation high throughput sequencing was combined with peptidomic assays to characterize the venom of the tarantula Haplopelma hainanum. The genes expressed in the venom glands were identified, and the bioactivity of their protein products was analyzed using the patch clamp technique. A total of 1,136 potential toxin precursors were identified that clustered into 90 toxin groups, of which 72 were novel. The toxin peptides clustered into 20 cysteine scaffolds that included between 4 and 12 cysteines, and 14 of these groups were newly identified in this spider. Highly abundant toxin peptide transcripts were present and resulted from hypermutation and/or fragment insertion/deletion. In combination with variable post-translational modifications, this genetic variability explained how a limited set of genes can generate hundreds of toxin peptides in venom glands. Furthermore, the intraspecies venom variability illustrated the dynamic nature of spider venom and revealed how complex components work together to generate diverse bioactivities that facilitate adaptation to changing environments, types of prey, and milking regimes in captivity.

Screening for voltage-gated sodium channel interacting peptides.

The voltage-gated sodium channel (VGSC) interacting peptide is of special interest for both basic research and pharmaceutical purposes. In this study, we established a yeast-two-hybrid based strategy to detect the interaction(s) between neurotoxic peptide and the extracellular region of VGSC. Using a previously reported neurotoxin JZTX-III as a model molecule, we demonstrated that the interactions between JZTX-III and the extracellular regions of its target hNav1.5 are detectable and the detected interactions are directly related to its activity. We further applied this strategy to the screening of VGSC interacting peptides. Using the extracellular region of hNav1.5 as the bait, we identified a novel sodium channel inhibitor SSCM-1 from a random peptide library. This peptide selectively inhibits hNav1.5 currents in the whole-cell patch clamp assays. This strategy might be used for the large scale screening for target-specific interacting peptides of VGSCs or other ion channels.

Nanoscale anisotropic plastic deformation in single crystal GaN.

Elasto-plastic mechanical deformation behaviors of c-plane (0001) and nonpolar GaN single crystals are studied using nanoindentation, cathodoluminescence, and transmission electron microscopy. Nanoindentation tests show that c-plane GaN is less susceptible to plastic deformation and has higher hardness and Young's modulus than the nonpolar GaN. Cathodoluminescence and transmission electron microscopy characterizations of indent-induced plastic deformation reveal that there are two primary slip systems for the c-plane GaN, while there is only one most favorable slip system for the nonplane GaN. We suggest that the anisotropic elasto-plastic mechanical properties of GaN are relative to its anisotropic plastic deformation behavior.PACS: 62.20.fq; 81.05.Ea; 61.72.Lk.

[Effect of total saponins from rhizomes and flowers of Panax notoginseng on tumor cell induced platelet aggregation].

OBJECTIVE: To investigate the effects of total saponins from rhizomes and flowers of Panax notoginseng on tumor cell induced platelet aggregation (TCIPA). METHODS: MDA-MB-231 breast carcinoma was applied as inductor and the platelet aggregation were investigated by Born's method in vitro and in vivo. RESULTS: Saponins from the flowers of Panax notoginseng inhibited TCIPA at the dose of 120, 240, 480 mg/L respectively in vitro and in vivo. Saponins from rhizomes of Panax notoginseng inhibited TCIPA only at its high dose in vivo. CONCLUSION: The saponins from Panax notoginseng has a dose-dependent inhibition of TCIPA. It may be a new class of antimetastatic agent.

[Inhibition of Jingzhaotoxin-V on Kv4.3 channel].

Kv4.3 channel is present in many mammalian tissues, predominantly in the heart and central nervous system. Its currents are transient, characterized by rapid activation and inactivation. In the hearts of most mammals, it is responsible for repolarization of the action potential of ventricular myocytes and is important in the regulation of the heart rate. Because of its central role in this important physiological process, Kv4.3 channel is a promising target for anti-arrhythmic drug development. Jingzhaotoxin-V (JZTX-V) is a novel peptide neurotoxin isolated from the venom of the spider Chilobrachys jingzhao. Whole-cell patch clamp recording showed that it partly blocked the transient outward potassium channels in dorsal root ganglion neurons of adult rats with an IC(50) value of 52.3 nmol/L. To investigate the effect of JZTX-V on Kv4.3 channel, JZTX-V was synthesized using the solid-phase chemical synthesis and separated by reverse phase high performance liquid chromatography (HPLC). The purity was tested by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MOLDI-TOF mass spectrometry). Two-electrode voltage-clamp technique was used to characterize the action of JZTX-V on Kv4.3 channels expressed in Xenopus laevis oocytes. As a result, JZTX-V displayed fast kinetics of inhibition and recovery from inactivation. Furthermore, it could inhibit Kv4.3 channel current in a time- and concentration-dependent manner with an IC(50) value of 425.1 nmol/L. The application of JZTX-V affected the activation and inactivation characteristics of Kv4.3 channel and caused a shift of the current-voltage relationship curve and the steady-state inactivation curve to depolarizing direction by approximately 29 mV and 10 mV, respectively. So we deduced that JZTX-V is a gating modifier toxin of Kv4.3 channel. Present findings should be helpful to develop JZTX-V into a molecular probe and drug candidate targeting to Kv4.3 channel in the myocardium.

Sequence-specific assignment of 1H-NMR resonance and determination of the secondary structure of Jingzhaotoxin-I.

Jingzhaotoxin-I (JZTX-I) purified from the venom of the spider Chilobrachys jingzhao is a novel neurotoxin preferentially inhibiting cardiac sodium channel inactivation by binding to receptor site 3. The structure of this toxin in aqueous solution was investigated using 2-D 1H-NMR techniques. The complete sequence-specific assignments of proton resonance in the 1H-NMR spectra of JZTX-I were obtained by analyzing a series of 2-D spectra, including DQF-COSY, TOCSY and NOESY spectra, in H2O and D2O. All the backbone protons except for Gln4 and more than 95% of the side-chain protons were identified by d alphaN, d alphadelta, d betaN and d NN connectivities in the NOESY spectrum. These studies provide a basis for the further determination of the solution conformation of JZTX-I. Furthermore, the secondary structure of JZTX-I was identified from NMR data. It consists mainly of a short triple-stranded antiparallel beta-sheet with Trp7-Cys9, Phe20-Lys23 and Leu28-Trp31. The characteristics of the secondary structure of JZTX-I are similar to those of huwentoxin-I (HWTX-I) and hainantoxin-IV (HNTX-IV), whose structures in solution have previously been reported.

Purification and characterization of raventoxin-I and raventoxin-III, two neurotoxic peptides from the venom of the spider Macrothele raveni.

The spider Macrothele raveni was recently identified as a new species of Genus Macrothele. The crude venom from M. raveni was found to be neurotoxic to mice and the LD(50) of the crude venom in mice was 2.852mg/kg. Two neurotoxic peptides, raventoxin-I and raventoxin-III, were isolated from the crude venom by ion-exchange and reverse phase high performance liquid chromatography. Raventoxin-I was the most abundant toxic component in the venom, while raventoxin-III was a lower abundant component. Both toxins can kill mice and block neuromuscular transmission in an isolated mouse phrenic nerve diaphragm preparation, but have no effect on cockroaches. The LD(50) of raventoxin-I in mice is 0.772mg/kg. The complete amino acid sequences of raventoxin-I and raventoxin-III were determined and found to consist of 43 and 29 amino acid residues, respectively. It was determined by mass spectrometry that all Cys residues from raventoxin-I and raventoxin-III are involved in disulphide bonds. raventoxin-III showed no significant sequence homology with any presently known neurotoxins in the protein/DNA databases, while raventoxin-I has limited sequence identity with delta-AcTx-Hv1 and delta-AcTx-Ar1, which target both mammalian and insect sodium channels. Both raventoxin-I and raventoxin-III only work on vertebrates, but not on insects. Moreover, raventoxin-I could exert an effect of first exciting and then inhibiting the contraction of mouse diaphragm muscle caused by electrically stimulating the phrenic nerve, but raventoxin-III could not.