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1.
Chem Biodivers ; 20(10): e202301015, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37624683

ABSTRACT

Bee bread (BB) is a beehive product generated upon fermentation of pollen combined with flower nectar and glandular secretions. The potential application of BB is related to its nutritional and functional components, including phenolic compounds. This is the first prospective study on palynological parameters, phenolics, antioxidant, and antibacterial activity of Chilean bee bread in vitro. The tested material exhibited high levels of phenolics (1340±186 mg GAE/100 g BB) and showed antioxidant capacity as determined by the FRAP (51±2 µmol Trolox equivalent/g BB) and ORAC-FL (643±64 µmol Trolox equivalent/g BB) and antibacterial activity against Streptococcus pyogenes. Furthermore, the phenolic acids and flavonoids was determined using liquid chromatography-mass spectrometry, and the concentration was determined using liquid chromatography with diode array detection. Kaempferol, quercetin, ferulic acid, and rutin were the main phenolics found. This study demonstrates the bioactive potential of Chilean BB and supports the evidence that this bee product is a promising source of antioxidants and antimicrobial compounds.

2.
Antioxidants (Basel) ; 12(1)2023 Jan 09.
Article in English | MEDLINE | ID: mdl-36671017

ABSTRACT

The contention that flavonoids' oxidation would necessarily lead to a loss of their antioxidant properties was recently challenged by the demonstration that quercetin oxidation leads to the formation of 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (Que-BZF), a metabolite whose antioxidant potency was notably higher than that of its precursor. Here, we compared and expanded the former observation to that of the quercetin analogue kaempferol. Oxidation of kaempferol led to the formation of a mixture of metabolites that included the 2-(4-hydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (Kae-BZF). Following the chromatographic isolation of Kae-BZF from such a mixture, its antioxidant, mitochondria- and cell-protecting, and NF-kB-inhibiting effects were assessed, and compared with those of Que-BZF, in Caco-2 cells exposed to indomethacin as a source of ROS. The concentrations of Que-BZF (100 nm) and Kae-BZF (1 nm) needed to attain their maximal protection effects were 50- and 5000-fold lower than those of their respective precursors. The former differences in concentrations were also seen when the abilities of Que-BZF and Kae-BZF to inhibit the indomethacin-induced activation of NF-kB were compared. These data not only reveal that the oxidative conversion of quercetin and kaempferol into their respective 2-benzoyl-2-hydroxy-3(2H)-benzofuranones (BZF) results in a considerable amplification of their original antioxidant properties, but also that the in the case of kaempferol, such amplification is 100-fold greater than that of quercetin.

3.
Antioxidants (Basel) ; 11(6)2022 Jun 10.
Article in English | MEDLINE | ID: mdl-35740036

ABSTRACT

Chickpeas are rich sources of bioactive compounds such as phenolic acids, flavonoids, and isoflavonoids. However, the contribution of insoluble-bound phenolics to their antioxidant properties remains unclear. Four varieties of chickpeas were evaluated for the presence of soluble (free and esterified) and insoluble-bound phenolics as well as their antiradical activity, reducing power and inhibition of peroxyl-induced cytotoxicity in human HuH-7 cells. In general, the insoluble-bound fraction showed a higher total phenolic content. Phenolic acids, flavonoids, and isoflavonoids were identified and quantified by UPLC-MS/MS. Taxifolin was identified for the first time in chickpeas. However, m-hydroxybenzoic acid, taxifolin, and biochanin A were the main phenolics found. Biochanin A was mostly found in the free fraction, while m-hydroxybenzoic acid was present mainly in the insoluble-bound form. The insoluble-bound fraction made a significant contribution to the reducing power and antiradical activity towards peroxyl radical. Furthermore, all extracts decreased the oxidative damage of human HuH-7 cells induced by peroxyl radicals, thus indicating their hepatoprotective potential. This study demonstrates that the antioxidant properties and bioactive potential of insoluble-bound phenolics of chickpeas should not be neglected.

4.
medRxiv ; 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34545370

ABSTRACT

Patients with immune conditions and immune-modifying therapies were excluded from the Covid-19 vaccine trials. Studies have shown conflicting response to different vaccines in persons receiving immune suppressors or biologics. The aim of this study is to evaluate humoral and cellular response to Covid-19 vaccines in patients with Inflammatory Bowel Disease (IBD) using biologic and/or immunomodulatory (IMM) therapies. Methods: Participants are adults with IBD receiving biologics or IMM planning to receive a Covid 19 vaccine. Cellular immunity (CD4+ and CD8+ T cell levels) with flow cytometry are measured at baseline and 2 weeks after each vaccine dose. Humoral immunity (antibody titers and neutralizing capacity,VNT%) is analyzed by ELISA at baseline, 2 weeks after each dose, and 6 and 12 months after vaccine. We present the early results of the first 19 subjects. The study is approved by the IRB. Results: 19 subjects (18 in biologics and 1 in IMM) who received 2 doses of the Pfizer-BioNTech vaccine are included. Total IgG antibodies increased 21.13 times after the first dose and 90 times after the second dose. VTN% increased 11.92 times after the first dose and 53.79 times after the second dose. When compared with a healthy control cohort, total IgG antibodies and VTN% were lower in the subjects after the first dose. After the second dose, IgG antibodies increased but remained lower than controls, but VTN% were similar to controls. CD4 and CD8 mean levels had an upward trend after vaccination. Conclusions: Neutralizing capacity response to the vaccine in subjects was similar to a healthy cohort in spite of lower increases in total IgG antibodies. The CD4 and CD8 results observed may support the capacity to mount an effective cellular response in patients on biologics. Larger studies are needed to determine vaccine efficacy in these patients.

5.
Antimicrob Agents Chemother ; 54(3): 1354-7, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20038618

ABSTRACT

During an island-wide PCR-based surveillance study of beta-lactam resistance in multidrug-resistant (MDR) Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter calcoaceticus-baumannii complex isolates obtained from 17 different hospitals, 10 KPC-positive Acinetobacter isolates were identified. DNA sequencing of the bla(KPC) gene identified KPC-2, -3, and -4 and a novel variant, KPC-10. This is the first report of a KPC-type beta-lactamase identified in Acinetobacter species.


Subject(s)
Acinetobacter Infections/epidemiology , Acinetobacter/classification , Acinetobacter/drug effects , beta-Lactam Resistance/genetics , beta-Lactamases/genetics , Acinetobacter/enzymology , Acinetobacter/isolation & purification , Acinetobacter Infections/microbiology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Population Surveillance/methods , Puerto Rico/epidemiology
6.
P R Health Sci J ; 24(3): 197-202, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16331860

ABSTRACT

OBJECTIVE: To describe the respiratory pathogens found in the bronchoalveolar lavage of a Puerto Rican population infected with the human immunodeficiency virus (HIV). BACKGROUND: Empirical treatment is an accepted strategy for management of HIV-related pneumonia, but it is usually recommended for countries that have knowledge of the prevalent organisms in their population. In Puerto Rico, we have relied on data from the United States, but ethnic and geographical differences have been reported. DESIGN: Case series of a HIV-infected population admitted to an academic hospital in Puerto Rico because of respiratory symptoms and who underwent diagnostic standard bronchoalveolar lavage. RESULTS: From August 1998 to March 2000, 32 bronchoalveolar lavages (BAL) were performed in 31 Puerto Rican HIV patients. Nine (31%) were female. Mean age was 37 years old. Predominant mode of infection of the virus was intravenous drug use in men and heterosexual contact in women. BAL was diagnostic in 17/32 (53%) of the cases. Identified respiratory pathogens were Pneumocystis carinii (5), Mycobacterium tuberculosis (4), Staphylococcus aureus (2), Pseudomonas aeuruginosa (1), Bordetella bronchiseptica (1), viridans streptococcus (1), Histoplasma capsulatum (1), Cytomegalovirus (1), and, Mycobacterium kansassi (1). Retrospective review of medical records of non bronchoscoped patients for the period added six culture confirmed tuberculosis cases increasing tuberculosis rate to 18% (10/56). CONCLUSIONS: Tuberculosis appears to be a more frequent pathogen in Puerto Rico than is reported in the United States. A larger study is needed to confirm this finding and thus to clarify whether an initial presumption of tuberculosis should be assumed in the Puerto Rican HIV population.


Subject(s)
Bronchoalveolar Lavage Fluid/microbiology , HIV Infections/microbiology , Adult , Female , Humans , Male , Middle Aged , Puerto Rico
7.
P R Health Sci J ; 24(1): 41-4, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15895876

ABSTRACT

The development of diarrhea in hospitalized patients is a frequently encountered clinical problem, which may be due to infectious or non-infectious causes. The purpose of this study was to identify which common community enteric pathogens, if any, are responsible for diarrheal episodes in hospitalized patients. Stool samples from 76 consecutive, hospitalized patients were analyzed utilizing routine bacterial cultures, smears for identification of ova and parasites and Enzyme-Link Immunoadsorbent Assay (ELISA) for enteric bacteria, parasites and viruses. The results obtained demonstrated that the usual community enteric pathogens were not identified as a major cause of nosocomial diarrhea. In hospital-acquired diarrhea, Clostridium difficile toxins assay was the only clinically significant test in the evaluation of these patients. As a result of this study a guideline for the management of this condition in hospitalized patients is presented.


Subject(s)
Diarrhea/microbiology , Gastroenteritis/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Diarrhea/epidemiology , Female , Gastroenteritis/epidemiology , Humans , Infant , Infant, Newborn , Inpatients/statistics & numerical data , Male , Middle Aged , Puerto Rico/epidemiology
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