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1.
Acta Med Philipp ; 58(6): 7-13, 2024.
Article in English | MEDLINE | ID: mdl-38846161

ABSTRACT

Background: Severe and critical COVID-19 disease is characterized by hyperinflammation involving pro-inflammatory cytokines, particularly IL-6. Tocilizumab is a monoclonal antibody that blocks IL-6 receptors. Objectives: This study evaluated the efficacy of tocilizumab in Filipino patients with severe to critical COVID-19 disease. Methods: This phase 3 randomized double-blind trial, included patients hospitalized for severe or critical COVID-19 in a 1:1 ratio to receive either tocilizumab plus local standard of care or placebo plus standard of care. Patients were eligible for a repeat IV infusion within 24-48 hours if they deteriorated or did not improve. Treatment success or clinical improvement was defined as at least two categories of improvement from baseline in the WHO 7-point Ordinal Scale of patient status, in an intention-to-treat manner. Results: Forty-nine (49) patients were randomized in the tocilizumab arm and 49 in the placebo arm. There was no significant difference in age, comorbidities, COVID-19 severity, need for mechanical ventilation, presence of acute respiratory distress syndrome, or biomarker levels between groups. Use of adjunctive therapy was similar between groups, with corticosteroid used in 91.8% in tocilizumab group and 81.6% in the placebo group, while remdesivir was used in 98% of participants in both groups.There was no significant difference between groups in terms of treatment success in both the intention-to-treat analysis (relative risk=1.05, 95% CI: 0.85-1.30) and per-protocol analysis (relative risk=0.98, 95% CI: 0.80 to 1.21). There was no significant difference in time to improvement of at least two categories relative to baseline on the 7-point Ordinal Scale of clinical status. Conclusion: The use of tocilizumab on top of standard of care in the management of patients with severe to critical COVID-19 did not result in significant improvement as defined by the WHO 7-point Ordinal Scale of patient status, nor in significant improvement in incidence of mechanical ventilation, incidence of ICU admission, length of ICU stay, and mortality rate.

2.
Acta Medica Philippina ; : 7-13, 2024.
Article in English | WPRIM (Western Pacific) | ID: wpr-1016390

ABSTRACT

Background@#Severe and critical COVID-19 disease is characterized by hyperinflammation involving pro-inflammatory cytokines, particularly IL-6. Tocilizumab is a monoclonal antibody that blocks IL-6 receptors. @*Objectives@#This study evaluated the efficacy of tocilizumab in Filipino patients with severe to critical COVID-19 disease. @*Methods@#This phase 3 randomized double-blind trial, included patients hospitalized for severe or critical COVID-19 in a 1:1 ratio to receive either tocilizumab plus local standard of care or placebo plus standard of care. Patients were eligible for a repeat IV infusion within 24-48 hours if they deteriorated or did not improve. Treatment success or clinical improvement was defined as at least two categories of improvement from baseline in the WHO 7-point Ordinal Scale of patient status, in an intention-to-treat manner. @*Results@#Forty-nine (49) patients were randomized in the tocilizumab arm and 49 in the placebo arm. There was no significant difference in age, comorbidities, COVID-19 severity, need for mechanical ventilation, presence of acute respiratory distress syndrome, or biomarker levels between groups. Use of adjunctive therapy was similar between groups, with corticosteroid used in 91.8% in tocilizumab group and 81.6% in the placebo group, while remdesivir was used in 98% of participants in both groups. There was no significant difference between groups in terms of treatment success in both the intention-to-treat analysis (relative risk=1.05, 95% CI: 0.85-1.30) and per-protocol analysis (relative risk=0.98, 95% CI: 0.80 to 1.21). There was no significant difference in time to improvement of at least two categories relative to baseline on the 7-point Ordinal Scale of clinical status. @*Conclusion@#The use of tocilizumab on top of standard of care in the management of patients with severe to critical COVID-19 did not result in significant improvement as defined by the WHO 7-point Ordinal Scale of patient status, nor in significant improvement in incidence of mechanical ventilation, incidence of ICU admission, length of ICU stay, and mortality rate.


Subject(s)
COVID-19 , Interleukin-6
3.
Front Immunol ; 14: 1123497, 2023.
Article in English | MEDLINE | ID: mdl-36926338

ABSTRACT

Purpose: This study was performed to determine the clinical biomarkers and cytokines that may be associated with disease progression and in-hospital mortality in a cohort of hospitalized patients with RT-PCR confirmed moderate to severe COVID-19 infection from October 2020 to September 2021, during the first wave of COVID-19 pandemic before the advent of vaccination. Patients and methods: Clinical profile was obtained from the medical records. Laboratory parameters (complete blood count [CBC], albumin, LDH, CRP, ferritin, D-dimer, and procalcitonin) and serum concentrations of cytokines (IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18, IFN-γ, IP-10, TNF-α) were measured on Days 0-3, 4-10, 11-14 and beyond Day 14 from the onset of illness. Regression analysis was done to determine the association of the clinical laboratory biomarkers and cytokines with the primary outcomes of disease progression and mortality. ROC curves were generated to determine the predictive performance of the cytokines. Results: We included 400 hospitalized patients with COVID-19 infection, 69% had severe to critical COVID-19 on admission. Disease progression occurred in 139 (35%) patients, while 18% of the total cohort died (73 out of 400). High D-dimer >1 µg/mL (RR 3.5 95%CI 1.83-6.69), elevated LDH >359.5 U/L (RR 1.85 95%CI 1.05-3.25), lymphopenia (RR 1.91 95%CI 1.14-3.19), and hypoalbuminemia (RR 2.67, 95%CI 1.05-6.78) were significantly associated with disease progression. High D-dimer (RR 3.95, 95%CI 1.62-9.61) and high LDH (RR 5.43, 95%CI 2.39-12.37) were also significantly associated with increased risk of in-hospital mortality. Nonsurvivors had significantly higher IP-10 levels at 0 to 3, 4 to 10, and 11 to 14 days from illness onset (p<0.01), IL-6 levels at 0 to 3 days of illness (p=0.03) and IL-18 levels at days 11-14 of illness (p<0.001) compared to survivors. IP-10 had the best predictive performance for disease progression at days 0-3 (AUC 0.81, 95%CI: 0.68-0.95), followed by IL-6 at 11-14 days of illness (AUC 0.67, 95%CI: 0.61-0.73). IP-10 predicted mortality at 11-14 days of illness (AUC 0.77, 95%CI: 0.70-0.84), and IL-6 beyond 14 days of illness (AUC 0.75, 95%CI: 0.68-0.82). Conclusion: Elevated D-dimer, elevated LDH, lymphopenia and hypoalbuminemia are prognostic markers of disease progression. High IP-10 and IL-6 within the 14 days of illness herald disease progression. Additionally, elevated D-dimer and LDH, high IP-10, IL-6 and IL-18 were also associated with mortality. Timely utilization of these biomarkers can guide clinical monitoring and management decisions for COVID-19 patients in the Philippines.


Subject(s)
COVID-19 , Hypoalbuminemia , Lymphopenia , Humans , Interleukin-18 , Interleukin-6 , Tertiary Care Centers , Pandemics , Chemokine CXCL10 , Philippines , Biomarkers , Cytokines , Disease Progression
5.
Article in English | WPRIM (Western Pacific) | ID: wpr-988893

ABSTRACT

Objective@#This study aims to validate a Filipino version of the questionnaire by Delclos et al on occupational risk factors and asthma among the health care workers of the Philippine General Hospital.@*Methodology@#Forward and backward translation method for bilinguals was used in this study. The Filipino translation was administered to 110 health care workers selected by stratified random sampling. After 24 hours, the retranslated English version was given to the same respondents. Testing for internal consistency reliability was done by computing for Cronbach's alpha. Construct validity was subsequently determined using the Cramer's V Coefficient.@*Results@#The Filipino questionnaire showed good internal consistency reliability, as shown by the overall Cronbach’s alpha of 0.9016, which is comparable to that of the original version by Delclos. Likewise, our Filipino questionnaire showed good construct validity, supported by the Cramer’s V coefficients ranging from 0.2204 (strong relationship) to 0.7843 (very strong relationship).@*Conclusion@#Overall, the Filipino version of the questionnaire for work-related asthma tested among the health care workers of Philippine General Hospital showed good reliability and validity. This may now be used as screening tool for occupational asthma among health care workers who are at risk of developing the disease. In addition, this research tool may be utilized to establish the prevalence of occupational asthma in hospitals and later on, aid in the development of a better working environment for the whole health care team.


Subject(s)
Health Personnel , Surveys and Questionnaires
6.
Food Chem X ; 15: 100445, 2022 Oct 30.
Article in English | MEDLINE | ID: mdl-36211773

ABSTRACT

In this study, cereals with high starch content, including brown rice, corn, and buckwheat were pretreated by extrusion. The physicochemical properties of extruded-puffed cereals obtained from different extrusion conditions were analyzed herein. The puffed extrudates exhibited lower bulk density, higher water solubility and gelatinization as compared to untreated cereals. The FTIR-ATR results confirmed a decrease in the crystalline structure of extruded-puffed cereals. A higher Vmax/Km value was observed in the enzymatic saccharification of puffed extrudates that significantly improved hydrolysis rate and yield. Finally, the high-maltose syrup was produced via the enzymatic hydrolysis of extruded-puffed cereals at high substrate concentrations (20 %). After hydrolysis for 180 min at an enzyme substrate ratio (E/S ratio) of 0.2, the syrup with dextrose equivalent (DE) value of 63, 62, and 61 were obtained from extruded-puffed brown rice, corn, and buckwheat, respectively. Our results showed the potential of using extruded-puffed cereals for producing high-maltose syrup.

7.
Preprint in English | bioRxiv | ID: ppbiorxiv-486882

ABSTRACT

The stem-loop II motif (s2m) is an RNA element present in viruses from divergent viral families, including astroviruses and coronaviruses, but its functional significance is unknown. We created deletions or substitutions of the s2m in astrovirus VA1 (VA1), classic human astrovirus 1 (HAstV1) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). For VA1, recombinant virus could not be rescued upon partial deletion of the s2m or substitutions of G-C base pairs. Compensatory substitutions that restored the G-C base-pair enabled recovery of VA1. For HAstV1, a partial deletion of the s2m resulted in decreased viral titers compared to wild-type virus, and reduced activity in a replicon system. In contrast, deletion or mutation of the SARS-CoV-2 s2m had no effect on the ability to rescue the virus, growth in vitro, or growth in Syrian hamsters. Our study demonstrates the importance of the s2m is virus-dependent.

8.
Plants (Basel) ; 11(3)2022 Jan 21.
Article in English | MEDLINE | ID: mdl-35161261

ABSTRACT

The recovery of physiologically bioactive ingredients from agricultural wastes as an abundant and low-cost source for the production of high value-added mutraceuticlas has been recognized and supported for the commercial interests and sustainable managements. In the extraction of geniposide for the development of natural food colorants from the dried fruits of Gardenia jasminoides Rubiaceae, the gardenia fruit waste (GFW) still remaining 0.86% (w/w) of crocins has always been discarded without any further treatments Until now, there was no simple and effective protocol for high-purity trans-crocein (TC) preparation without the coexistence of non-biologically active cis-crocein from GFW. We proposed an effective process to obtain the compound as follows. Crocins were extracted firstly by 50% of ethanol in the highest yield of 8.61 mg/g (w/w) from GFW. After the HPD-100 column fractionation in the collecting of crocins, the conversion ratio of 75% of crocins to crocetins can be obtained from the commercial available enzyme- Celluclast® 1.5 L. The crocins hydrolyzed products, were then separated through the HPD-100 resin adsorption and finally purified with the centrifugal partition chromatography (CPC) in single-step to obtain TC in a purity of 96.76 ± 0.17%. Conclusively, the effective enzyme transformation and purification co-operated with CPC technologies on crocins resulted in a high purity product of TC may be highly application in the commercial production.

9.
J Colloid Interface Sci ; 606(Pt 2): 1340-1351, 2022 Jan 15.
Article in English | MEDLINE | ID: mdl-34500150

ABSTRACT

The fabrication of stable and efficient catalysts for green and economic catalytic transformation is significant. Here, highly stable covalent triazine frameworks (CTF-1) were used as the supporting material for anchoring ultrafine Pd nanoparticles (NPs) via a facile impregnation process and a one-pot calcination-reduction strategy. The widespread dispersion of ultrafine Pd NPs was a result of the abundant high nitrogen-content triazine groups of CTF-1 that endowed the catalyst Pd@CTF-1 with high catalytic activity. The catalytic performance of Pd@CTF-1 was demonstrated by the one-pot N-alkylation of benzaldehyde with aniline (or nitrobenzene) under mild reaction conditions, and Pd@CTF-1 exhibited a wide range of general applicability for N-alkylation reactions. The reaction mechanism for the N-alkylation reaction was also studied in detail. In addition, the Pd@CTF-1 catalyst exhibited high thermal and chemical stability, maintaining good catalytic efficiency after multiple reaction cycles. This study provides new insights for the fabrication of organic supporting materials with highly dispersed active catalytic sites that can lead to excellent catalytic performance for efficient, economical, and green reactions.

10.
Preprint in English | medRxiv | ID: ppmedrxiv-21257945

ABSTRACT

ObjectiveTo provide high-quality data for COVID-19 research, we validated COVID-19 clinical indicators and 22 associated computed phenotypes, which were derived by machine learning algorithms, in the Mass General Brigham (MGB) COVID-19 Data Mart. Materials and MethodsFifteen reviewers performed a manual chart review for 150 COVID-19 positive patients in the data mart. To support rapid chart review for a wide range of target data, we offered the Digital Analytic Patient Reviewer (DAPR). DAPR is a web-based chart review tool that integrates patient notes and provides note search functionalities and a patient-specific summary view linked with relevant notes. Within DAPR, we developed a COVID-19 validation task-oriented view and information extraction logic, enabled fast access to data, and considered privacy and security issues. ResultsThe concepts for COVID-19 positive cohort, COVID-19 index date, COVID-19 related admission, and the admission date were shown to have high values in all evaluation metrics. For phenotypes, the overall specificities, PPVs, and NPVs were high. However, sensitivities were relatively low. Based on these results, we removed 3 phenotypes from our data mart. In the survey about using the tool, participants expressed positive attitudes towards using DAPR for chart review. They assessed the validation was easy and DAPR helped find relevant information. Some validation difficulties were also discussed. Discussion and ConclusionDAPRs patient summary view accelerated the validation process. We are in the process of automating the workflow to use DAPR for chart reviews. Moreover, we will extend its use case to other domains.

11.
Malays Orthop J ; 15(1): 12-15, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33880142

ABSTRACT

A series of mortalities among musculoskeletal tumour patients secondary to medical illnesses during the first few months of the pandemic highlighted the need to review our methods of communication with patients. Prominent among patients' concerns had been a fear of consulting at hospitals and a lack of ready access to health care. Recommendations are made for proactive consultation and patient education, identifying at-risk patients for follow-up and probing for possible co-morbidities. Telemedicine use is encouraged bearing in mind its inherent limitations. A network of physicians and pharmaceutical representatives is an added help we can offer our patients who may be isolated by community quarantine.

12.
Preprint in English | bioRxiv | ID: ppbiorxiv-441501

ABSTRACT

With the emergence of SARS-CoV-2 variants with increased transmissibility and potential resistance, antibodies and vaccines with broadly inhibitory activity are needed. Here we developed a panel of neutralizing anti-SARS-CoV-2 mAbs that bind the receptor binding domain of the spike protein at distinct epitopes and block virus attachment to cells and its receptor, human angiotensin converting enzyme-2 (hACE2). While several potently neutralizing mAbs protected K18-hACE2 transgenic mice against infection caused by historical SARS-CoV-2 strains, others induced escape variants in vivo and lost activity against emerging strains. We identified one mAb, SARS2-38, that potently neutralizes all SARS-CoV-2 variants of concern tested and protects mice against challenge by multiple SARS-CoV-2 strains. Structural analysis showed that SARS2-38 engages a conserved epitope proximal to the receptor binding motif. Thus, treatment with or induction of inhibitory antibodies that bind conserved spike epitopes may limit the loss of potency of therapies or vaccines against emerging SARS-CoV-2 variants.

13.
Food Chem Toxicol ; 150: 112020, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33513408

ABSTRACT

Melanoma is one of the most dangerous malignant epidermal cancers. Natto freeze-drying extract (NFDE) and natto water extract (NWE) were isolated from natto, soybeans fermented by Bacillus subtilis natto, which were assessed as potential anti-melanoma agents. Cell cytotoxicity assays revealed significant anti-melanoma effects of NFDE and NWE in a dose-dependent manner, and exhibited low influences on normal skin cells, including Hs68, HaCaT and adipose tissue-derived stem cells (ADSCs), respectively. Through a flow cytometer assay and autophagy acridine orange staining, the cellular death phenomenon shifted from autophagy to apoptosis with the increased dosages. Reactive oxygen species (ROS) were enhanced using DCFDA (2,7-dichlorodihydrofluorescein diacetate) staining when melanoma cells were treated with the extract. NFDE and NWE treatments increase the oxidative stress of cancer cells and cause apoptosis by inhibiting AMP-activated protein kinase (AMPK). NFDE and NWE were considered to play a critical role in cell death through ROS adjustment, autophagy regulation and apoptosis promotion.


Subject(s)
Apoptosis/drug effects , Autophagy/drug effects , Bacillus subtilis/physiology , Melanoma/drug therapy , Animals , Bacillus subtilis/chemistry , Cell Line , Cell Survival/drug effects , Fermentation , Fibroblasts , Gene Expression Regulation, Neoplastic/drug effects , Humans , Japan , Mice , Soy Foods , Glycine max/metabolism
14.
Clin Infect Dis ; 73(11): e4539-e4548, 2021 12 06.
Article in English | MEDLINE | ID: mdl-32785589

ABSTRACT

BACKGROUND: Imipenem combined with the ß-lactamase inhibitor relebactam has broad antibacterial activity, including against carbapenem-resistant gram-negative pathogens. We evaluated efficacy and safety of imipenem/cilastatin/relebactam in treating hospital-acquired/ventilator-associated bacterial pneumonia (HABP/VABP). METHODS: This was a randomized, controlled, double-blind phase 3 trial. Adults with HABP/VABP were randomized 1:1 to imipenem/cilastatin/relebactam 500 mg/500 mg/250 mg or piperacillin/tazobactam 4 g/500 mg, intravenously every 6 hours for 7-14 days. The primary endpoint was day 28 all-cause mortality in the modified intent-to-treat (MITT) population (patients who received study therapy, excluding those with only gram-positive cocci at baseline). The key secondary endpoint was clinical response 7-14 days after completing therapy in the MITT population. RESULTS: Of 537 randomized patients (from 113 hospitals in 27 countries), the MITT population comprised 264 imipenem/cilastatin/relebactam and 267 piperacillin/tazobactam patients; 48.6% had ventilated HABP/VABP, 47.5% APACHE II score ≥15, 24.7% moderate/severe renal impairment, 42.9% were ≥65 years old, and 66.1% were in the intensive care unit. The most common baseline pathogens were Klebsiella pneumoniae (25.6%) and Pseudomonas aeruginosa (18.9%). Imipenem/cilastatin/relebactam was noninferior (P < .001) to piperacillin/tazobactam for both endpoints: day 28 all-cause mortality was 15.9% with imipenem/cilastatin/relebactam and 21.3% with piperacillin/tazobactam (difference, -5.3% [95% confidence interval {CI}, -11.9% to 1.2%]), and favorable clinical response at early follow-up was 61.0% and 55.8%, respectively (difference, 5.0% [95% CI, -3.2% to 13.2%]). Serious adverse events (AEs) occurred in 26.7% of imipenem/cilastatin/relebactam and 32.0% of piperacillin/tazobactam patients; AEs leading to treatment discontinuation in 5.6% and 8.2%, respectively; and drug-related AEs (none fatal) in 11.7% and 9.7%, respectively. CONCLUSIONS: Imipenem/cilastatin/relebactam is an appropriate treatment option for gram-negative HABP/VABP, including in critically ill, high-risk patients. CLINICAL TRIALS REGISTRATION: NCT02493764.


Subject(s)
Cilastatin , Imipenem , Adult , Aged , Anti-Bacterial Agents/adverse effects , Azabicyclo Compounds , Cilastatin/adverse effects , Hospitals , Humans , Imipenem/adverse effects , Piperacillin , Tazobactam , Ventilators, Mechanical
15.
Article in English | WPRIM (Western Pacific) | ID: wpr-913055

ABSTRACT

@#A series of mortalities among musculoskeletal tumour patients secondary to medical illnesses during the first few months of the pandemic highlighted the need to review our methods of communication with patients. Prominent among patients’ concerns had been a fear of consulting at hospitals and a lack of ready access to health care. Recommendations are made for proactive consultation and patient education, identifying at-risk patients for follow-up and probing for possible co-morbidities. Telemedicine use is encouraged bearing in mind its inherent limitations. A network of physicians and pharmaceutical representatives is an added help we can offer our patients who may be isolated by community quarantine.

16.
Preprint in English | bioRxiv | ID: ppbiorxiv-102038

ABSTRACT

Antibody-based interventions against SARS-CoV-2 could limit morbidity, mortality, and possibly disrupt epidemic transmission. An anticipated correlate of such countermeasures is the level of neutralizing antibodies against the SARS-CoV-2 spike protein, yet there is no consensus as to which assay should be used for such measurements. Using an infectious molecular clone of vesicular stomatitis virus (VSV) that expresses eGFP as a marker of infection, we replaced the glycoprotein gene (G) with the spike protein of SARS-CoV-2 (VSV-eGFP-SARS-CoV-2) and developed a high-throughput imaging-based neutralization assay at biosafety level 2. We also developed a focus reduction neutralization test with a clinical isolate of SARS-CoV-2 at biosafety level 3. We compared the neutralizing activities of monoclonal and polyclonal antibody preparations, as well as ACE2-Fc soluble decoy protein in both assays and find an exceptionally high degree of concordance. The two assays will help define correlates of protection for antibody-based countermeasures including therapeutic antibodies, immune {gamma}-globulin or plasma preparations, and vaccines against SARS-CoV-2. Replication-competent VSV-eGFP-SARS-CoV-2 provides a rapid assay for testing inhibitors of SARS-CoV-2 mediated entry that can be performed in 7.5 hours under reduced biosafety containment.

17.
Preprint in English | medRxiv | ID: ppmedrxiv-20026500

ABSTRACT

OBJECTIVETo study the neurological manifestations of patients with coronavirus disease 2019 (COVID-19). DESIGNRetrospective case series SETTINGThree designated COVID-19 care hospitals of the Union Hospital of Huazhong University of Science and Technology in Wuhan, China. PARTICIPANTSTwo hundred fourteen hospitalized patients with laboratory confirmed diagnosis of severe acute respiratory syndrome from coronavirus 2 (SARS-CoV-2) infection. Data were collected from 16 January 2020 to 19 February 2020. MAIN OUTCOME MEASURESClinical data were extracted from electronic medical records and reviewed by a trained team of physicians. Neurological symptoms fall into three categories: central nervous system (CNS) symptoms or diseases (headache, dizziness, impaired consciousness, ataxia, acute cerebrovascular disease, and epilepsy), peripheral nervous system (PNS) symptoms (hypogeusia, hyposmia, hypopsia, and neuralgia), and skeletal muscular symptoms. Data of all neurological symptoms were checked by two trained neurologists. RESULTSOf 214 patients studied, 88 (41.1%) were severe and 126 (58.9%) were non-severe patients. Compared with non-severe patients, severe patients were older (58.7 {+/-} 15.0 years vs 48.9 {+/-} 14.7 years), had more underlying disorders (42 [47.7%] vs 41 [32.5%]), especially hypertension (32 [36.4%] vs 19 [15.1%]), and showed less typical symptoms such as fever (40 [45.5%] vs 92 [73%]) and cough (30 [34.1%] vs 77 [61.1%]). Seventy-eight (36.4%) patients had neurologic manifestations. More severe patients were likely to have neurologic symptoms (40 [45.5%] vs 38 [30.2%]), such as acute cerebrovascular diseases (5 [5.7%] vs 1 [0.8%]), impaired consciousness (13 [14.8%] vs 3 [2.4%]) and skeletal muscle injury (17 [19.3%] vs 6 [4.8%]). CONCLUSIONCompared with non-severe patients with COVID-19, severe patients commonly had neurologic symptoms manifested as acute cerebrovascular diseases, consciousness impairment and skeletal muscle symptoms.

18.
Food Chem Toxicol ; 136: 111050, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31843533

ABSTRACT

The pickled radish can be kept at room temperature for years without spoilage. 2,6-dihydroxyacetophenone (DHAP), 4-hydroxybenzaldehyde (HBA), and 4-hydroxyphenethyl alcohol (4-HPEA) were first found from the pickled radish. The structures of three phenolic compounds were elucidated by analysis of their nuclear magnetic resonance and high-resolution electro-spray ionization mass spectrometry data. All these phenolic compounds showed good free radical scavenging capacity except HBA. Both DHAP and 4-HPEA also showed high ferric reducing ability. DHAP showed good antimicrobial activity against Escherichia coli, Bacillus subtilis, and Canidia albicans. HBA demonstrated antimicrobial activity against E. coli and C. albicans but not B. subtilis. Based on the results of MTT assay, these compounds did not show cytotoxicity to LO2 cell line. All results indicated the pickled radish had antioxidant and antimicrobial phenolic compounds. To the best of our knowledge, this report is the first to answer partially the question of why pickled foods can be kept at room temperature for years without spoilage based on the evidence of three phenolic compounds.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Free Radical Scavengers/pharmacology , Phenols/pharmacology , Raphanus/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/toxicity , Antifungal Agents/isolation & purification , Antifungal Agents/toxicity , Bacillus subtilis/drug effects , Candida albicans/drug effects , Cell Line , Escherichia coli/drug effects , Free Radical Scavengers/isolation & purification , Free Radical Scavengers/toxicity , Humans , Microbial Sensitivity Tests , Phenols/isolation & purification , Phenols/toxicity
19.
Food Chem Toxicol ; 135: 110993, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31765702

ABSTRACT

3S, 3'S-Astaxanthin is the most powerful antioxidant to scavenge free radicals in the world. In this study, a 3S, 3'S-astaxanthin biosynthesis pathway was constructed in a probiotic yeast, Kluveromyces marxianus, denoted YEAST, and its bioactive metabolites were extracted for biofunctional assessments. The bio-safety examination was achieved by two animal models as following: First, no significant toxic effects on YEAST groups were found in zebrafish; Second, after feeding YEAST for 4 weeks, the rat-groups showed no visible abnormality, and no significant change of the body weight and blood biochemistry tests. The inhibition of lung metastasis of melanoma cells and the increment of the survival rate were demonstrated by feeding YEAST and injecting the intravenous commercial astaxanthin in vivo rodent model. Based on in vitro assays of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging analysis, ferrous ion chelating ability, reducing power assessment, and mushroom tyrosinase inhibition evaluation, YEAST-astaxanthin showed anti-oxidative and tyrosinase suppressive properties. Taken together, the 3S, 3'S-astaxanthin producing probiotic yeast is safe to be used in the bio-synthesis of functional and pharmaceutical compounds, which have broad industrial applications on cosmetic, food and feed additive and healthcare.


Subject(s)
Kluyveromyces/metabolism , Melanoma, Experimental/pathology , Metabolic Engineering , Neoplasm Metastasis/prevention & control , Probiotics , Animals , Antioxidants/pharmacology , Female , Male , Melanoma, Experimental/enzymology , Mice , Mice, Inbred BALB C , Monophenol Monooxygenase/antagonists & inhibitors , Rats , Rats, Sprague-Dawley , Xanthophylls/chemistry , Xanthophylls/metabolism , Xanthophylls/pharmacology , Zebrafish
20.
Antioxidants (Basel) ; 8(11)2019 Nov 07.
Article in English | MEDLINE | ID: mdl-31703361

ABSTRACT

In this research we utilized extracts from two different nature products, Achatina fulica and Heimiella retispora, to enhance skin moisturizing abilities, anti-oxidative properties, and cell proliferations. It was observed that two polysaccharides with anti-oxidative effects by chelating metal ions reduced oxidative stress and further blocked the formation of reactive oxygen species syntheses. To detect whether there was a similar effect within the cellular mechanism, a flow cytometry was applied for sensing the oxidative level and it was found that both materials inhibited the endogenous oxidative stress, which was induced by phorbol-12-myristate-13-acetate (PMA). Both polysaccharides also stimulated the production of collagen to maintain skin tightness and a moisturizing effect. In summary, we developed two macromolecular polysaccharides with potential applications in dermal care.

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