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1.
J Agric Food Chem ; 72(3): 1582-1591, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38221880

RESUMO

The widespread use of Bacillus thuringiensis toxins as insecticides has brought about resistance problems. Anti-idiotypic nanobody approaches provide new strategies for resistance management and toxin evolution. In this study, the monoclonal antibody generated against the receptor binding region Domain II of Cry2Aa toxin was used as a target to screen materials with insecticidal activity. After four rounds of screening, anti-idiotypic nanobody 1C12 was obtained from the natural alpaca nanobody phage display library. To better analyze the activity of 1C12, soluble 1C12 was expressed by the Escherichia coli BL21 (DE3). The results showed that 1C12 not only binds the midgut brush border membrane vesicles (BBMV) of two lepidopteran species and cadherin CR9-CR11 of three lepidopteran species but also inhibits Cry2Aa toxins from binding to CR9-CR11. The insect bioassay showed that soluble 1C12 caused 25.65% and 23.61% larvae mortality of Helicoverpa armigera and Plutella xylostella, respectively. Although 1C12 has low insecticidal activity, soluble 1C12 possesses the ability to screen a broad-spectrum recognition of the toxin binding region of lepidopteran cadherins and can be used for the identification of the toxin binding region of other lepidopteran cadherins and the subsequent evolution of Cry2Aa toxin. The present study demonstrates a new strategy to screen for the production of novel insecticides.


Assuntos
Bacillus thuringiensis , Inseticidas , Animais , Inseticidas/química , Endotoxinas/metabolismo , Bacillus thuringiensis/química , Caderinas/metabolismo , Larva/metabolismo , Proteínas Hemolisinas/metabolismo , Proteínas de Bactérias/metabolismo
2.
Biochem Biophys Res Commun ; 691: 149308, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38029542

RESUMO

This study tried to generate anti-idiotypic antibodies (Ab2s) which mimic Cry2Aa toxin using a phage-display antibody library (2.8 × 107 CFU/mL). The latter was constructed from a mouse immunized with F (ab')2 fragments digested from anti-Cry2Aa polyclonal antibodies. The F (ab')2 fragments and Plutella xylostella (P. xylostella) brush border membrane vesicles (BBMV) were utilized as targets for selection. Eight mouse phage-display single-chain variable fragments (scFvs) were isolated and identified by enzyme-linked immunoassay (ELISA), PCR and DNA sequencing after four rounds of biopanning. Among them, M3 exhibited the highest binding affinity with F (ab')2, while M4 bound the best with the toxin binding region of cadherin of P. xylostella (PxCad-TBR). Both of these two fragments were chosen for prokaryotic expression. The expressed M3 and M4 proteins with molecular weights of 30 kDa were purified. The M4 showed a binding affinity of 29.9 ± 2.4 nM with the PxCad-TBR and resulted in 27.8 ± 4.3 % larvae mortality against P. xylostella. Computer-assisted molecular modeling and docking analysis showed that mouse scFv M4 mimicked some Cry2Aa toxin binding sites when interacting with PxCad-TBR. Therefore, anti-idiotypic antibodies generated by BBMV-based screening could be useful for the development of new bio-insecticides as an alternative to Cry2Aa toxin for pest control.


Assuntos
Bacteriófagos , Inseticidas , Lepidópteros , Anticorpos de Cadeia Única , Animais , Camundongos , Biblioteca Gênica , Anticorpos de Cadeia Única/química , Endotoxinas/metabolismo , Anticorpos Anti-Idiotípicos , Biblioteca de Peptídeos
3.
Anal Biochem ; 677: 115270, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37531991

RESUMO

Bacillus thuringiensis (Bt) Cry toxins have been widely used in the development of genetically modified organisms (GMOs) for pest control. This work aimed to establish more cost effective methods for used Cry2Aa toxins. Three immunoassay methods (IC-ELISA, DAS-ELISA, and CLEIA) were successfully developed in this work. The mAb was used as the detecting antibody, for the IC-ELISA, the range of IC20 to IC80 was 1.11 µg/mL - 60.70 µg/mL, and an IC50 of 10.65 µg/mL. For the DAS-ELISA, the limit of detection (LOD) and limit of quantitation (LOQ) were 10.76 ng/mL and 20.70 ng/mL, respectively. For the CLEIA, the LOD and LOQ were 6.17 ng/mL and 7.40 ng/mL, respectively. The scFv-based detections were the most sensitive for detecting Cry2Aa. The LOD and LOQ for the DAS-ELISA were 118.75 ng/mL and 633.48 ng/mL, respectively. The LOD and LOQ for the CLEIA, read as 37.47 ng/mL and 70.23 ng/mL, respectively. The fact that Cry2Aa toxin was recovered in spiked grain samples further demonstrated that the approaches might be used to identify field samples. These methods provided good sensitivity, stability, and applicability for detecting Cry2Aa toxin, promising ultrasensitive monitoring and references for Cry toxins risk assessment.


Assuntos
Anticorpos Monoclonais , Bacillus thuringiensis , Proteínas de Bactérias/análise , Endotoxinas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas Hemolisinas
5.
Plants (Basel) ; 12(13)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37446958

RESUMO

Barleria albostellata (Acanthaceae) is a shrub located in South Africa and is relatively understudied. However, plants within this genus are well known for their medicinal and ethnopharmacological properties. This study aimed to characterise the phytochemical compounds and antibacterial efficacies of B. albostellata. Phytochemical analysis, fluorescence microscopy and gas chromatography-mass spectrometry (GC-MS) analysis were performed to determine the composition of compounds that may be of medicinal importance. Crude leaf and stem extracts (hexane, chloroform and methanol) were subjected to an antibacterial analysis against several pathogenic microorganisms. The qualitative phytochemical screening of leaf and stem extracts revealed the presence various compounds. Fluorescence microscopy qualitatively assessed the leaf and stem powdered material, which displayed various colours under bright and UV light. GC-MS chromatograms represents 10-108 peaks of various compounds detected in the leaf and stem crude extracts. Major pharmacologically active compounds found in the extracts were alpha-amyrin, flavone, phenol, phytol, phytol acetate, squalene and stigmasterol. Crude extracts positively inhibited Gram-positive and Gram-negative bacteria. Significance was established at p < 0.05 for all concentrations and treatments. These results indicate that the leaves and stems of B. albostellata are rich in bioactive compounds, which could be a potential source of antibacterial agents for treating various diseases linked to the pathogenic bacteria studied. Future discoveries from this plant could advance the use of indigenous traditional medicine and provide novel drug leads.

6.
Anticancer Agents Med Chem ; 23(13): 1545-1566, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37073157

RESUMO

BACKGROUND: Medicinal plants are known to contain numerous phytometabolites with suggested pharmacological value. Literature suggests that the medicinal use of phytometabolites in its natural state has limited success due to poor absorption rates. Currently, the focus lies on synthesizing phytometabolites extracted from medicinal plants and silver ions to generate nano-scale carriers with specialized properties. Thus, the nano-synthesis of phytometabolites with silver (Ag+) ions is proposed. The use of silver is promoted due to its known antibacterial and antioxidant effectiveness, among many. Nanotechnology allows for the green generation of nano-scaled particles that are able to penetrate target areas due to its size and unique structure. Therefore, this study aimed to generate a novel protocol for the synthesis of AgNP's using the leaf and stembark extracts of C. erythrophyllum. In addition, the biological activity of the generated nanoparticles was evaluated. OBJECTIVES: To synthesis silver nanoparticles (AgNP's) using the leaf and stembark extracts of Combretum erythrophyllum. The relative shape, size, distribution, and zeta potential of the synthesised particles were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Energy-dispersive X-ray (EDX), Nanoparticle tracking analysis (NTA), and UV Spectrophotometry (UV -vis). To screen the synthesised particles for its potential antibacterial, apoptotic and cytotoxic properties. METHODS: A novel protocol for the synthesis of silver nanoparticles (AgNP's) using the leaf and stembark extracts of Combretum erythrophyllum was established. The generated AgNP's were characterised using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Energy-dispersive X-ray (EDX), Nanoparticle tracking analysis (NTA), and UV Spectrophotometry (UV -vis). Furthermore, the AgNP's were evaluated for their antibacterial, cytotoxic and apoptotic activity against a range of bacterial strains and cancer cells. Characterisation was based upon particle size, shape and elemental silver composition. RESULTS: Within the stembark extract, synthesised nanoparticles were large, spherical in shape and dense in elemental silver composition. While synthesised nanoparticles of the leaf extract were small to medium in size, varied in shape established and contained minimal quantities of silver (substantiated by the TEM and NTA results). Furthermore, it was established that the synthesized nanoparticles exhibited high antibacterial properties due to the conducted antibacterial assay. The FTIR analysis revealed the presence of numerous functional groups within active compounds found in the synthesised extracts. Functional groups found varied between the leaf and stembark extracts, each with proposed pharmacological activity. CONCLUSION: Presently, antibiotic-resistant bacteria are continuously evolving thus, posing as a threat to conventional drug delivery systems. Nanotechnology provides a platform that enables the formulation of a low-toxicity and hypersensitive drug delivery system. Further studies evaluating the biological activity of extracts of C. erythrophyllum synthesized with silver nanoparticles could enhance its proposed pharmaceutical value.


Assuntos
Antineoplásicos , Combretum , Nanopartículas Metálicas , Plantas Medicinais , Humanos , Nanopartículas Metálicas/química , Prata/farmacologia , Prata/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Antineoplásicos/farmacologia , Antibacterianos/química , Difração de Raios X
7.
Asia Pac J Clin Oncol ; 19(6): 672-680, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36855017

RESUMO

AIM: The OPTIM1SE study observed long-term real-world outcomes of cetuximab-based infusional 5-fluorouracil (5-FU) regimens for first-line treatment of metastatic colorectal cancer (mCRC) across Asia-Pacific and Middle East regions, aiming to characterize their use, effectiveness, and safety in routine practice. METHODS: OPTIM1SE was a prospective, open-label, observational study. Patients with untreated KRAS wild-type mCRC and distant metastases were treated per locally approved labels and monitored for 3 years via electronic medical records. The primary endpoint was the overall response rate (ORR). Secondary endpoints included safety, progression-free survival (PFS), and overall survival (OS). RESULTS: From November 19, 2013, to June 30, 2016, 520 patients were enrolled in 51 sites. Patients were mostly male (61.2%), with a mean age of 58.5 (±12.0) years; 420 patients received leucovorin, 5-FU, and irinotecan-based regimens and 94 received leucovorin, 5-FU, and oxaliplatin. The most common primary tumor site was the rectum (38.8%), with liver metastases (65.0%). ORR was 45.4% (95% CI, 41.1%-49.7%), including 26 patients (5.0%) with a complete response. Median PFS was 9.9 months (95% CI, 8.2-11.0); median OS (mOS) was 30.8 months (95% CI, 27.9-33.6). Higher mOS was associated with tumors of left compared with right-sided origin (hazard ratio, 0.69 [95% CI, 0.49-0.99]); higher ORR was also associated with liver metastases compared with all other metastases (55.4% vs. 40.2%). Adverse events were consistent with the known safety profile of cetuximab. CONCLUSION: Cetuximab-based 5-FU regimens were effective first-line treatments for mCRC in routine practice, particularly in patients with left-sided disease and liver metastases only.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Hepáticas , Neoplasias Retais , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Cetuximab/uso terapêutico , Leucovorina/efeitos adversos , Estudos Prospectivos , Fluoruracila/efeitos adversos , Resultado do Tratamento , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Proteínas Proto-Oncogênicas p21(ras)/uso terapêutico , Camptotecina/uso terapêutico
8.
Plants (Basel) ; 12(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36840116

RESUMO

Diospyros villosa is traditionally used for an anti-bacterial property. Its cytotoxic effects have not been studied before. Therefore, this study aimed to examine the nutritional properties as well the cytotoxic effects of D. villosa. The leaves and stem barks were subjected to three different extraction methods (methanol, chloroform and hexane) and their nanoparticles were synthesized at two different temperatures (room temperature and at 80 °C). Thereafter, extracts were assessed using the associated AOCC protocols, for their nutritional content (moisture, fibre, proteins, lipid, ash and hydrolysable carbohydrates). Diospyros villosa extracts and their corresponding nanoparticles were then incubated overnight with cancerous and noncancerous cell lines to evaluate their cytotoxic potential. The nutritional analysis revealed that both young and mature leaves were rich sources of protein having values of 14.95% and 11.37% respectively. The moisture content was observed to be higher in all the leaf types (8.54 ± 0.75%, 9.67 ± 0.98% and 7.40 ± 0.80%) compared to the stem (2.13 ± 0.07%) respectively. The MTT cytotoxicity assay showed that the cell viability of MCF-7 cell lines was significantly lower when exposed to hexane and chloroform leaves extracts of D. villosa (IC50 of 26.64 and 26.07 µg mL-1) respectively, compared to camptothecin (36.54 µg mL-1). Similarly, the MCF-7 cell viability was observed to be significantly lower when exposed to hexane and chloroform stem extracts of D. villosa (IC50 of 24.57 and 3.92 µg mL-1), compared to camptothecin (36.54 µg mL-1). The cell viability of A549 cell lines was also found lower when exposed to the hexane and chloroform extracts (IC50 of 7.76 and 4.59 µg mL-1) compared to camptothecin (IC50 of 19.26 µg mL-1). Furthermore, the viability of A549 cell lines was found lower when exposed to hexane and chloroform stem extracts of D. villosa (IC50 of 10.67 and 5.35 µg mL-1) compared to camptothecin (19.26 µg mL-1). The biosynthesized nanoparticles further displayed an anticancer activity with an IC50 value of 4.08 µg mL-1 when compared to the control (36.54 µg mL-1). However, the HEK293 cell viability was observed to be significantly higher on exposure to hexane stem extracts of D. villosa (IC50 of 158.5 µg mL-1) compared to camptothecin (IC50 of 14.77 µg mL-1). Therefore, Diospyros villosa leaves, stem bark and nanoparticles synthesized showed high potential for being considered as a candidate for an anti-cancer regimen.

9.
Hemasphere ; 6(12): e803, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36452029

RESUMO

Asian patientswith chronic lymphocytic leukemia (CLL) exhibit immunoglobulin heavy variable (IGHV) gene repertoires that are distinct from those observed in Western populations, and a higher proportion of Asian CLL patients carry heavy loads of somatic hypermutations (SHM) within the B-cell receptor immunoglobulins (BcR IG). Due to the low regional incidence of CLL in Asia, only a limited number of studies had attempted to probe the phenomenon of BcR IG stereotypy in Asian populations. In this study, we analyzed the IGHV-IGHD-IGHJ gene rearrangements from a series of 255 CLL patients recruited in a nationwide, multicenter study in Taiwan. Our analysis revealed that the IGHV gene repertoire was characterized by evident biases, with IGHV3-7, IGHV4-34, and IGHV3-23 being the most frequent rearranged IGHV genes, and a higher proportion of cases carrying mutated IGHV. In terms of BcR stereotypy, the incidence of major subsets was less frequent in this cohort, with subsets #77 and #28A being the most common, while the incidence of minor subsets was approximately equivalent to that reported in the Western cohorts. With this study, we provide evidence that CLL in Asia is indeed associated with distinct immunogenetic characteristics regarding IGHV gene usage, SHM status, and BcR IG stereotypy.

10.
Microb Pathog ; 172: 105779, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36116609

RESUMO

Nicotinamide Adenine Dinucleotide-Dependent (NADH) flavin oxidoreductase and NADH oxidase (NOX) are important virulence factors of Mycoplasma hyopneumoniae (Mhp), which are devoted to the function of adhesion, oxidative stress damage and apoptosis to host cells in our previous studies. Here, immune responses of NADH flavin oxidoreductase (NFOR) and NOX in mice and immune efficacy inoculated with intramuscular (IM), intranasal (IN), intramuscular unite intranasal (IM + IN) approaches were evaluated and compared. Cellular immunity levels, systemic immune and local mucosal immune responses were investigated by indirect enzyme-linked immunosorbent assay (iELISA) and quantitative reverse transcription PCR (qRT-PCR). Mice inoculated with NFOR and NOX by IM and IN or IM + IN could induce obvious secretion of specific immunoglobulin G (IgG) and secretory immunoglobulin A antibodies (sIgA) compared to those in negative control group. IM + IN inoculation resulted in systemic and local mucosal immune responses that were strongly produced. Moreover, Mhp NFOR and NOX could activate local mucosal immune responses mediated by Th1 and Th17 cells by IN. Our finding supported the notion that IM + IN was an effective immunization route for Mhp, which lays a foundation for more effective prevention of Mhp, and provides theoretical basis for the development of new subunit vaccines of Mhp.


Assuntos
Mycoplasma hyopneumoniae , Camundongos , Animais , Imunidade nas Mucosas , NAD , Fatores de Virulência , Células Th17 , FMN Redutase , Vacinas Bacterianas , Imunoglobulina G , Vacinas de Subunidades , Imunoglobulina A Secretora , Flavinas , Camundongos Endogâmicos BALB C
11.
BMC Vet Res ; 18(1): 126, 2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35366872

RESUMO

BACKGROUND: Mycoplasma hyopneumoniae (M. hyopneumoniae) is the etiological agent of enzootic pneumonia, a highly infectious swine respiratory disease that distributed worldwide. The pathogenesis and virulence factors of M. hyopneumoniae are not fully clarified. As an important virulence factor of bacteria, nicotinamide adenine dinucleotide (NADH) oxidase (NOX) participates in host-pathogen interaction, however, the function of NOX involved in the pathogenesis of M. hyopneumoniae is not clear. RESULTS: In this study, significant differences in NOX transcription expression levels among different strains of M. hyopneumoniae differed in virulence were identified, suggesting that NOX may be correlated with M. hyopneumoniae virulence. The nox gene of M. hyopneumoniae was cloned and expressed in Escherichia coli, and polyclonal antibodies against recombinant NOX (rNOX) were prepared. We confirmed the enzymatic activity of rNOX based on its capacity to oxidize NADH to NAD+. Flow cytometry analysis demonstrated the surface localization of NOX, and subcellular localization analysis further demonstrated that NOX exists in both the cytoplasm and cell membrane. rNOX was depicted to mediate adhesion to immortalized porcine bronchial epithelial cells (hTERT-PBECs). Pre-neutralizing M. hyopneumoniae with anti-rNOX antibody resulted in a more than 55% reduction in the adhesion rate of high- and low-virulence M. hyopneumoniae strains to hTERT-PBECs. Moreover, a significant difference appeared in the decline in CCU50 titer between virulent (168) and virulence-attenuated (168L) strains. NOX not only recognized and interacted with host fibronectin but also induced cellular oxidative stress and apoptosis in hTERT-PBECs. The release of lactate dehydrogenase by NOX in hTERT-PBECs was positively correlated with the virulence of M. hyopneumoniae strains. CONCLUSIONS: NOX is considered to be a potential virulence factor of M. hyopneumoniae and may play a significant role in mediating its pathogenesis.


Assuntos
Mycoplasma hyopneumoniae , Animais , Complexos Multienzimáticos , Mycoplasma hyopneumoniae/genética , NAD , NADH NADPH Oxirredutases , Oxirredutases/metabolismo , Suínos , Virulência
12.
Environ Monit Assess ; 194(3): 166, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35142880

RESUMO

Shared sanitation facilities have been hailed as an innovative approach to solve the challenge with sanitation access. However, these facilities may act as hotspots for disease transmission due to unhygienic conditions. In this study we used quantitative (based on Escherichia coli contamination) techniques to assess the health risks associated with the use of community ablution blocks (CABs). The most contaminated surfaces were the cistern handle (5.7 Log10 cfu/cm2) and internal pull latch (5.8 Log10 cfu/cm2). Based on the E. coli contamination, at least two people out of 100 CAB users might be potentially infected when they touch "hot" surfaces. These risks were modelled assuming transfer of potentially pathogenic E. coli from these surfaces to the mouth. The incorporation of risk-reduction measures, such as wiping of these surfaces or washing of hands, could potentially result in significant reduction of infection risks. The most significant risk-reduction intervention was determined to be wiping of the contact surfaces, especially twice prior to contact. A combination of risk-reduction interventions could further reduce the risks. This study shows that contamination of contact surfaces within shared CABs could lead to increased risks of infections, requiring measures aimed at reducing the associated risks. The risk assessment framework used in this study could therefore be applied in similar settings to estimate associated health risks with the use of such facilities.


Assuntos
Infecções por Escherichia coli/transmissão , Escherichia coli , Saneamento , Monitoramento Ambiental , Infecções por Escherichia coli/epidemiologia , Humanos , Medição de Risco , África do Sul
13.
Br J Cancer ; 126(7): 1018-1026, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34921230

RESUMO

BACKGROUND: The objective of this study was to evaluate the efficacy and safety of induction chemotherapy (ICT), GOFL (gemcitabine, oxaliplatin plus fluorouracil (5-FU)/leucovorin) versus modified FOLFIRINOX (irinotecan, oxaliplatin plus 5-FU/leucovorin), followed by concurrent chemoradiotherapy (CCRT) in locally advanced pancreatic adenocarcinoma (LAPC). METHODS: Chemo-naive patients with measurable LAPC were eligible and randomly assigned to receive biweekly ICT with either mFOLFIRINOX or GOFL for 3 months. Patients without systemic progression would have 5-FU- or gemcitabine-based CCRT (5040 cGy/28 fractions) and were then subjected to surgery or continuation of chemotherapy until treatment failure. The primary endpoint was 9-month progression-free survival (PFS) rate. RESULTS: Between July 2013 and January 2019, 55 patients were enrolled. After ICT, 21 (77.8%) of 27 patients who received mFOLFIRINOX and 17 (60.7%) of 28 patients who received GOFL completed CCRT. Of them, one and five had per-protocol R0/R1 resection. On intent-to-treat analysis, the 9-month PFS rate, median PFS and overall survival in mFOLFIRINOX and GOFL arms were 30.5% versus 35.9%, 6.6 (95% confidence interval: 5.9-12.5) versus 7.6 months (3.9-12.3) and 19.6 (13.4-22.9) versus 17.9 months (13.4-23.9), respectively. Grade 3-4 neutropenia and diarrhoea during induction mFOLFIRINOX and GOFL were 37.0% versus 21.4% and 14.8% versus 3.6%, respectively. CONCLUSION: Induction GOFL and mFOLFIRINOX followed by CCRT provided similar clinical outcomes in LAPC patients. GOV IDENTIFIER: NCT01867892.


Assuntos
Adenocarcinoma , Quimiorradioterapia , Quimioterapia de Indução , Neoplasias Pancreáticas , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia/efeitos adversos , Fluoruracila , Humanos , Quimioterapia de Indução/efeitos adversos , Leucovorina , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Taiwan
14.
FASEB J ; 36(1): e22052, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34862979

RESUMO

The glycocalyx surrounds every eukaryotic cell and is a complex mesh of proteins and carbohydrates. It consists of proteoglycans with glycosaminoglycan side chains, which are highly sulfated under normal physiological conditions. The degree of sulfation and the position of the sulfate groups mainly determine biological function. The intact highly sulfated glycocalyx of the epithelium may repel severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) through electrostatic forces. However, if the glycocalyx is undersulfated and 3-O-sulfotransferase 3B (3OST-3B) is overexpressed, as is the case during chronic inflammatory conditions, SARS-CoV-2 entry may be facilitated by the glycocalyx. The degree of sulfation and position of the sulfate groups will also affect functions such as immune modulation, the inflammatory response, vascular permeability and tone, coagulation, mediation of sheer stress, and protection against oxidative stress. The rate-limiting factor to sulfation is the availability of inorganic sulfate. Various genetic and epigenetic factors will affect sulfur metabolism and inorganic sulfate availability, such as various dietary factors, and exposure to drugs, environmental toxins, and biotoxins, which will deplete inorganic sulfate. The role that undersulfation plays in the various comorbid conditions that predispose to coronavirus disease 2019 (COVID-19), is also considered. The undersulfated glycocalyx may not only increase susceptibility to SARS-CoV-2 infection, but would also result in a hyperinflammatory response, vascular permeability, and shedding of the glycocalyx components, giving rise to a procoagulant and antifibrinolytic state and eventual multiple organ failure. These symptoms relate to a diagnosis of systemic septic shock seen in almost all COVID-19 deaths. The focus of prevention and treatment protocols proposed is the preservation of epithelial and endothelial glycocalyx integrity.


Assuntos
COVID-19 , Células Endoteliais , Endotélio Vascular , Glicocálix , SARS-CoV-2/metabolismo , COVID-19/metabolismo , COVID-19/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Glicocálix/metabolismo , Glicocálix/patologia , Glicocálix/virologia , Humanos , Estresse Oxidativo , Sulfotransferases/metabolismo
15.
Front Oncol ; 11: 764912, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868987

RESUMO

Therapeutic options for metastatic CRC (mCRC) have changed significantly in recent years, greatly increasing the complexity of therapeutic decision-making. Although oncology guidelines have helped improve the care process, guidelines may also limit the flexibility to individualize in-clinic decision-making. This consensus paper addresses specific gaps in the current international guidelines to assist Taiwanese colon and rectal experts make specific therapeutic choices. Over 3 years and three meetings with selected experts on "real-world" Taiwanese practice patterns for mCRC, consensus was achieved. The experts also discussed specific questions during in-depth one-on-one consultation. Outcomes of the discussion were then correlated with published evidence by an independent medical writer. The final consensus includes clinically implementable recommendations to provide guidance in treating Taiwanese mCRC patients. The consensus includes criteria for defining fit and unfit intensive treatment patients, treatment goals, treatment considerations of molecular profiles, treatment consideration, and optimal treatment choices between different patient archetypes, including optimal treatment options based on RAS, BRAF, and microsatellite instability (MSI) status. This consensus paper is the second in the Taiwan Society of Colon and Rectal Surgeons (TSCRS) Consensus series to address unmet gaps in guideline recommendations in lieu of Taiwanese mCRC management. Meticulous discussions with experts, the multidisciplinary nature of the working group, and the final drafting of the consensus by independent medical professionals have contributed to the strong scientific value of this consensus.

16.
Breast Cancer Res Treat ; 189(3): 665-676, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34553296

RESUMO

PURPOSE: Neratinib, an irreversible pan-HER tyrosine kinase inhibitor, has demonstrated systemic efficacy and intracranial activity in various stages of HER2+breast cancer. NALA was a phase III randomized trial that assessed the efficacy and safety of neratinib+capecitabine (N+C) against lapatinib+capecitabine (L+C) in HER2+ metastatic breast cancer (mBC) patients who had received ≥ 2 HER2-directed regimens. Descriptive analysis results of the Asian subgroup in the NALA study are reported herein. METHODS: 621 centrally assessed HER2+ mBC patients were enrolled, 202 of whom were Asian. Those with stable, asymptomatic brain metastases (BM) were eligible for study entry. Patients were randomized 1:1 to N (240 mg qd) + C (750 mg/m2 bid, day 1-14) with loperamide prophylaxis or to L (1250 mg qd) + C (1000 mg/m2 bid, day 1-14) in 21-day cycles. Co-primary endpoints were centrally assessed progression-free survival (PFS) and overall survival (OS). Secondary endpoints included time to intervention for central nervous system (CNS) disease, objective response rate, duration of response (DoR), clinical benefit rate, and safety. RESULTS: 104 and 98 Asian patients were randomly assigned to receive N+C or L+C, respectively. Median PFS of N+C and L+C was 7.0 and 5.4 months (P = 0.0011), respectively. Overall cumulative incidence of intervention for CNS disease was lower with N+C (27.9 versus 33.8%; P = 0.039). Both median OS (23.8 versus 18.7 months; P = 0.185) and DoR (11.1 versus 4.2 months; P < 0.0001) were extended with N+C, compared to L+C. The incidences of grade 3/4 treatment emergent adverse events (TEAEs) and TEAEs leading to treatment discontinuation were mostly comparable between the two arms. Diarrhea and palmar-plantar erythrodysesthesia were the most frequent TEAEs in both arms, similar to the overall population in incidence and severity. CONCLUSION: Consistent with the efficacy profile observed in the overall study population, Asian patients with HER2+ mBC, who had received ≥ 2 HER2-directed regimens, may also benefit from N+C. No new safety signals were noted. CLINICAL TRIAL REGISTRATION: NCT01808573.


Assuntos
Neoplasias da Mama , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Capecitabina/uso terapêutico , Feminino , Humanos , Lapatinib/uso terapêutico , Quinolinas , Receptor ErbB-2/genética , Resultado do Tratamento
17.
An Acad Bras Cienc ; 93(2): e20190343, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076085

RESUMO

The chemical composition and biological activity of the essential oil extracted from the fresh leaves and stem bark of Grewia lasiocarpa was determined for the first time in this study. The essential oils were extracted by hydrodistillation and identified by GC-MS and FTIR. The antibacterial, antioxidant activity and total phenolic content of essential oils were determined. The major compounds identified were phytol (22.6%); α-farnesene (8.62%); n-hexadecanoic acid (7.24%); farnesol (4.61%) in the leaves, and 2-methylheptadecane (7.24%); heptacosane (7.60%); heptadecane, 2,6,10,14-tetramethyl (7.30%). The presence of aromatic, alkanes and phenolic compounds were revealed by FTIR analysis. The in silico oral prediction shows that some of the components are orally safe. The essential oil from the leaves showed cytotoxic activity at 1mg/mL(IC50 =555.70 µg/mL) against HeLa cells. The oils exhibited no significant antioxidant activity (IC50 >1 000 µg/mL) with <100 mg/g GAE of total phenol. The essential oils showed different degrees of activities against Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853) and Klebsiella pneumoniae (ATCC 314588) at 10 µg/mL, 5 µg/mL and 2.5 µg/mL. These results might provide a future reference basis for further exploration of more of its medicinal application.


Assuntos
Grewia , Óleos Voláteis , Antibacterianos/farmacologia , Antioxidantes , Células HeLa , Humanos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Óleos de Plantas
18.
Anal Biochem ; 625: 114222, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33932355

RESUMO

The anti-idiotypic antibody is widely used in the field of immunology to simulate structural features or even induce the biological activity of antigens. In this study, we obtained seven anti-idiotypic single-chain variable fragments (scFv) antibodies of Cry2Aa toxin from a phage-displayed mutant library constructed using error-prone PCR technique. A mutant designated 2-12B showed the best binding ability amongst all anti-idiotypic scFv isolates to Plutella xylostella brush border membrane vesicles (BBMVs). 2-12B and Cry2Aa toxin shared a potential receptor of polycalin in P. xylostella BBMVs. Homology modeling and molecular docking demonstrated that 2-12B and Cry2Aa toxin have seven common binding amino acid residues in polycalin. Insect bioassay results suggested that 2-12 had insecticidal efficacy against P. xylostella larvae. These results indicated that the Cry2Aa anti-idiotypic scFv antibody 2-12B partially mimicked the structure and function of Cry2Aa toxin. The anti-idiotypic scFv antibody provides the basic material for the future study of surrogate molecules or new insecticidal materials.


Assuntos
Anticorpos Anti-Idiotípicos/química , Anticorpos Monoclonais/química , Toxinas de Bacillus thuringiensis/química , Endotoxinas/química , Proteínas Hemolisinas/química , Região Variável de Imunoglobulina/química , Anticorpos de Cadeia Única/química , Animais , Anticorpos Anti-Idiotípicos/genética , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Anti-Idiotípicos/metabolismo , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Toxinas de Bacillus thuringiensis/imunologia , Toxinas de Bacillus thuringiensis/metabolismo , Membrana Celular/metabolismo , Endotoxinas/imunologia , Endotoxinas/metabolismo , Proteínas Hemolisinas/imunologia , Proteínas Hemolisinas/metabolismo , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Região Variável de Imunoglobulina/metabolismo , Simulação de Acoplamento Molecular , Mariposas , Mutação , Biblioteca de Peptídeos , Conformação Proteica , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/metabolismo
19.
Brain Res ; 1767: 147524, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34015358

RESUMO

A wide range of microorganisms can infect the central nervous system (CNS). The immune response of the CNS provides limited protection against microbes penetrating the blood-brain barrier. This results in a neurological deficit and sometimes leads to high morbidity and mortality rates despite advanced therapies. For the last two decades, different studies have expanded our understanding of the molecular basis of human neuroinfectious diseases, especially concerning the contributions of mast cell interactions with other central nervous system compartments. Brain mast cells are multifunctional cells derived from the bone marrow and reside in the brain. Their proximity to blood vessels, their role as "first responders" their unique receptors systems and their ability to rapidly release pathogen responsive mediators enable them to exert a crucial defensive role in the host-defense system. This review describes key biological and physiological functions of mast cells, concerning their ability to recognize pathogens via various receptor systems, followed by a coordinated and selective mediator release upon specific interactions with pathogenic stimulating factors. The goal of this review is to direct attention to the possibilities for therapeutic applications of mast cells against bacterial and viral related infections. We also focus on opportunities for future research activating mast cells via adjuvants.


Assuntos
Imunidade/efeitos dos fármacos , Mastócitos/metabolismo , Mastócitos/patologia , Animais , Infecções Bacterianas/patologia , Encéfalo/citologia , Encéfalo/metabolismo , Comunicação Celular , Sistema Nervoso Central/patologia , Humanos , Inflamação/patologia , Mastócitos/fisiologia , Viroses/patologia
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