An improved method to assess the encapsulation response in arthropods.

Ecoimmunology explores how ecological factors and evolutionary processes influence immune responses across various taxa and how immune responses trade-off with other traits. Studying immune responses requires biologically meaningful immunoassays applicable to a broad range of taxa and are sensitive enough to detect changes in the immune response. Useful immunoassays should also correlate with immunocompetence and fitness. The encapsulation response, a complex immune mechanism in arthropods, serves as a robust method for ecoimmunological investigations. However, traditional methods to test the encapsulation response can require long training. This study introduces an innovative, cost-effective method for assessing the encapsulation immune response in arthropods, which simplifies the procedure by reducing the training time and skill required. Our modified device utilizes a pen and syringe assembly for inserting monofilaments into arthropod larvae. We compared our device against traditional methods. Despite the new method being 22% faster, it did not compromise the accuracy or effectiveness of the encapsulation response when compared with traditional techniques, demonstrating similar degrees of melanization and encapsulation. Our method allowed for more accessible participation by less experienced researchers, such as undergraduates, facilitating their involvement in ecoimmunological research.

A high-performance method for quantitation of aflatoxins B1, B2, G1, G2: Full validation for raisin, peanut matrices, and survey of related products at Ho Chi Minh City.

Optimization and validation for simultaneous quantitation of four aflatoxins B1, B2, G1, and G2 in peanuts and raisins were performed on ultra-performance liquid chromatography in a combination of fluorescence detector, without derivatization. The advantages were short analysis time, simple sample handling, and reduced solvent consumption. Instrument detection limits of AFB1, AFB2, AFG1, and AFG2 were 0.07, 0.01, 0.1, and 0.008 µg/kg, respectively, lower than those obtained by LCMSMS and HPLC-FLD with derivatization. Two solvent mixtures were chosen for two different matrices whose matrix effect was not negligible (2.81%-8.04% for peanuts and 5.63%-11.43% for raisins). The linear ranges were from 0.2 to 20 µg/L for AFB1 and AFG1 and from 0.05 to 5 µg/L for AFB2 and AFG2. The limits of detection and quantification were 0.025-0.1 and 0.075-0.3 µg/kg for peanuts and raisins, respectively. Recoveries at three other concentrations from 0.75 to 125 µg/kg of total aflatoxins were obtained between 76.5% and 99.8% (with RSD < 6%) following the SANTE 11312/2021. Validation parameters complied with the requirements of ISO/IEC 17025:2017. The extracts and the sample could be stabilized at 4°C and 20°C for 24 h and at -20°C for up to 21 days, respectively. Thus, the study can be used as a standard method for the analysis of Aflatoxins (AFs) in peanut and raisin matrices. Investigation of 350 peanut samples collected at Markets in the central districts of HCM city showed that 28.6% were contaminated with AFB1 from 0.31 up to 554 µg/kg; 13.4% contained AFB2, and 5.7% of AFG1 in the range of 0.4-53 µg/kg and 0.4-9.57 µg/kg, respectively; AFG2 (about 0.6%) was detected from 0.45 to 0.75 µg/kg. Meanwhile, 12.8% exceeded the total aflatoxins limit, and 13.4% exceeded the AFB1 limit. AFs were almost not found in the 350 raisin samples.

Impact of the COVID-19 Pandemic on the Severity and Early Postoperative Outcomes of Acute Appendicitis.

Background The coronavirus disease 2019 (COVID-19) pandemic caused changes in surgical practice. For acute appendicitis (AA), measures to control the pandemic might hinder patients from seeking medical care timely, resulting in increasing severity, postoperative complications, and mortality. This study aimed to investigate whether the COVID-19 pandemic had a negative impact on the severity and postoperative outcomes of patients with AA. Methodology We retrospectively reviewed medical records of AA patients treated operatively at Nhan Dan Gia Dinh Hospital hospital from June 1st to September 30th in three consecutive years: pre-pandemic (2019)/Group 1, minor waves (2020)/Group 2, and major wave (2021)/Group 3 (2021). Data were collected focusing on the duration of symptoms, severity of AA, time from admission to operation, postoperative complications, and mortality. Results There were 1,055 patients, including 452 patients in Group 1, 409 in Group 2, and 194 in Group 3. The overall number of patients decreased mainly in non-complicated AA. The percentages of hospital admission after 24 hours gradually increased (20.8%, 27.9%, and 43.8%, p < 0.05). The percentages of complicated AA in Group 2 and Group 3 were statistically higher than in Group 1 (39% and 55% vs. 31%, p < 0.05). Waiting time for operation increased to five hours during the major wave. Laparoscopic appendectomy was performed in 98-99% of AA patients during the pandemic, with an early postoperative complication rate of 5-9% and a mortality rate of 0.2-1%. Conclusions Although the percentages of hospital admission after 24 hours and complicated AA increased, laparoscopic appendectomy was still feasible and effective and should be maintained as the standard management for AA during the COVID-19 pandemic.

Experience of Peripheral Blood CD34+ Stem Cells Collection in Autoimmune Patients.

BACKGROUND: Autologous Hematopoietic Stem Cell Transplantation with or without CD34+ selection is being used successfully to treat patients with severe and refractory autoimmune disease. This study describes our experience of CD34+ stem cell mobilization, harvesting and selection in autoimmune patients based on conditions in Vietnam - the developing country. METHODS: Eight autoimmune patients (four patients with Myasthenia Gravis and four patients with Systemic Lupus Erythematosus) underwent PBSC mobilization with granulocyte colony-stimulating factor (G-CSF) and cyclophosphamide. The apheresis was performed on a Terumo BCT Spectra Optia machine. CD34+ hematopoetic stem cells were collected from the leukapheresis by CliniMACS Plus device using CD34 Enrichment KIT. CD34+ cells, T and B lymphocytes were counted on a FACS BD Canto II device. RESULTS: Eight patients (4 MG and 4 SLE) including 5 females and 3 males were involved in this study. The mean age of the patients was 33.13 ± 16.64 years (ranging from 13 to 58 years). The average number of days for mobilization was 7.9 ± 1.6 days, whereas the average number of days for harvesting was 1.5 ± 0.5 days. There was no difference in the number of days for mobilization and harvesting between the MG and SLE groups. The number of CD34+ cells in peripheral blood (PB) on the day of harvesting was 108.37 ± 59.64 x 106 cells/L. There was a significant difference in white blood cell (WBC), neutrophil, monocyte, and platelet cell counts between before and after mobilization. On the day of stem cell harvesting, variables such as WBC, neutrophil, lymphocyte, monocyte, platelet, CD34+ cell counts, and hemoglobin were not different between the MG and SLE groups. The CD34+ recovery percentage following the CD34+ selection procedure was 68.8%, whereas almost 99.9% of the T and B lymphocytes, and NK cells in the PBSC products were eliminated. CONCLUSIONS: Very first attempts in mobilizing, harvesting, and selecting CD34+ stem cells were successful, paving the way for autoimmune patients to have autologous hematopoietic stem cell transplantation in Vietnam.

Quantification of 397 pesticide residues in different types of commercial teas: Validation of high accuracy methods and quality assessment.

Analytical methods with high sensitivity and accuracy were successfully validated for the quantification of 397 pesticides in different types of tea. For the UPLC-MS/MS method, 191 pesticides of 200 ones in total had "soft" matrix effects and could be quantified by calibration curves in the solvent. For the GC-MS/MS method, matrix-matched calibration curves were established on a mixed blank including white, green, oolong and black organic teas. The method limit of quantifications ranged from 1.0 µg kg-1 to 10 µg kg-1 (UPLC-MS/MS) and 1.0 µg kg-1 to 50 µg kg-1 (GC-MS/MS), with 70-120% of recovery. These methods was subsequently applied to 106 tea samples from several origins, in which 26 samples contained at least one pesticide violation, with a total of 43 pesticide residue violations. The most frequently detected pesticides were neonicotinoids, synthetic pyrethroids, and triazole fungicides. Taiwan had the most pesticide-contaminated samples followed by China, Vietnam, and India.

Vietnam's success story against COVID-19.

Vietnam's close proximity to China where the COVID-19 outbreak started made it one of the countries expected to have widespread transmission of the virus. However, the country opposed this expectation and attained low spread of COVID-19 infection due to its proactive approaches in containing the disease. As of March 11, 2021, Vietnam has a total of 2529 confirmed cases, equivalent to 26 cases per one million population-compared to the global rate of 15,223 cases. The low-cost model approach used by Vietnam in dealing with previous public health issues, tackle the importance of a strategic public health system, good governance, and citizen cooperation in the fight against COVID 19 pandemic. This paper aims to analyze Vietnam's achievement in its early and continued success in combating COVID-19 by taking into account various aspects of its health system and experience on outbreaks that have previously occurred and how these can be applied to current COVID-19 responses.

Determination of 400 pesticide residues in green tea leaves by UPLC-MS/MS and GC-MS/MS combined with QuEChERS extraction and mixed-mode SPE clean-up method.

Maximum residue limits (MRLs) for pesticides have been established in teas for quality control and protection of consumer health in many countries and regions, including Europe. It is, however, challenging to quantify multi-pesticide residues at low concentrations in complex matrices, such as tea. In this study, highly sensitive, efficient, and rugged analytical methods were adapted for simultaneous determination of 400 pesticide residues in green tea products using ultra performance liquid and gas chromatography coupled to tandem mass spectroscopy (UPLC-MS/MS and GC-MS/MS). Matrix effects were minimized by combining QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction and mixed-mode SPE clean-up with different sorbents in sample preparation. A C18 SPE cartridge paired with SPE GCB/PSA proved to be the most effective clean-up method and enabled 225 pesticide residues to be quantified, based on solvent calibration curves (154 residues using UPLC-MS/MS and 71 residues using GC-MS/MS). The analytical methods were validated fully in accordance with the SANTE/11945/2015. LOQs for most pesticides (386/400 or 96.5%) were below 10 µg/kg, i.e., less than the EU MRL (5-70 mg/kg). Thus, these approaches can be applied for routine analysis of multi-pesticide residues in green tea.

Addition of Partial Envelope Domain II into Envelope Domain III of Dengue Virus Antigen Potentiates the Induction of Virus-Neutralizing Antibodies and Induces Protective Immunity.

Dengue virus (DENV) comprises four serotypes in the family Flaviviridae and is a causative agent of dengue-related diseases, including dengue fever. Dengue fever is generally a self-limited febrile illness. However, secondary infection of patients with a suboptimal antibody (Ab) response provokes life-threatening severe dengue hemorrhagic fever or dengue shock syndrome. To develop a potent candidate subunit vaccine against DENV infection, we developed the EDII-cEDIII antigen, which contains partial envelope domain II (EDII) including the fusion loop and BC loop epitopes together with consensus envelope domain III (cEDIII) of all four serotypes of DENV. We purified Ab from mice after immunization with EDII-cEDIII or cEDIII and compared their virus neutralization and Ab-dependent enhancement of DENV infection. Anti-EDII-cEDIII Ab showed stronger neutralizing activity and lower Ab-dependent peak enhancement of DENV infection compared with anti-cEDIII Ab. Following injection of Ab-treated DENV into AG129 mice, anti-EDII-cEDIII Ab ameliorated DENV infection in tissues with primary and secondary infection more effectively than anti-cEDIII Ab. In addition, anti-EDII-cEDIII Ab protected against DENV1, 2, and 4 challenge. We conclude that EDII-cEDIII induces neutralizing and protective Abs, and thus, shows promise as a candidate subunit vaccine for DENV infection.

Carbon Coated CoO Electrode Synthesized by Urea-Assisted Auto Combustion for Rechargeable Lithium Battery.

A simple and low cost urea-assisted auto-combustion route was investigated for the synthesis of carbon coated CoO nanocomposite. CHN analysis determined the carbon content in CoO/C nanocomposite to be very low as 0.27 wt%. The results show that the CoO/C nanocomposite electrode displays marked lower charge transfer resistance, high lithium storage capacity, and much better rate capability than original CoO nanoparticles electrode.

Statistical tests of demographic heterogeneity theories.

In this paper we develop predictions from models of life-long demographic heterogeneity. These predictions are then compared to observations of mortality in large laboratory populations of Drosophila melanogaster. We find that the demographic heterogeneity models either require levels of variation that far exceed what would be considered biologically plausible, or they predict a much larger number of very old individuals than we actually observe. We conclude that the demographic heterogeneity models are not reasonable explanations of demographic patterns and are weakly motivated biological models.

The First Six-Membered "True" Heterocycle - Hydrogen-Bond-Assisted Ladder Formation in a KOCNPS Ring System.

A ladder of alternating K2 S2 and K2 O2 rings exists in K[Ph2 P(S)NC(O)Ph]⋅MeOH, the first six-membered "true" heterocycle, in the solid state (see picture). A simple P-N bond-forming reaction between benzamide and Ph2 PCl gives the precursor Ph2 P(S)NHC(O)Ph, from which the potassium salt can be generated by reaction with KOtBu.