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1.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445472

RESUMO

Background: Platelet-Rich Plasma (PRP) induces bone regeneration; however, there is low evidence supporting its efficacy in bone healing. The lack of a standardized protocol of administration represents the main obstacle to its use in the clinical routine for bone defects' treatment. The purpose of this study was to characterize PRP and elucidate its osteogenic potential. Methods: Platelet count, fibrinogen levels, and growth factors concentration were measured in PRP obtained by four apheresis procedures. HOB-01-C1, a pre-osteocytic cell line, was used to examine the effects of different PRP dilutions (from 1% to 50%) on cell viability, growth, and differentiation. Gene expression of RUNX2, PHEX, COL1A1, and OCN was also assayed. Results: PRP showed a mean 4.6-fold increase of platelets amount compared to whole blood. Among the 36 proteins evaluated, we found the highest concentrations for PDGF isoforms, EGF, TGF-ß and VEGF-D. PDGF-AA positively correlated with platelet counts. In three of the four tested units, 25% PRP induced a growth rate comparable to the positive control (10% FBS); whereas, for all the tested units, 10% PRP treatment sustained differentiation. Conclusions: This study showed that PRP from apheresis stimulates proliferation and differentiation of pre-osteocyte cells through the release of growth factors from platelets.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Osteócitos/citologia , Osteogênese , Plasma Rico em Plaquetas/metabolismo , Medicina Regenerativa , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Perfilação da Expressão Gênica , Humanos , Técnicas In Vitro , Osteócitos/metabolismo
2.
Int J Mol Sci ; 22(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202728

RESUMO

The prognosis of patients with oral squamous carcinoma (OSCC) largely depends on the stage at diagnosis, the 5-year survival rate being approximately 30% for advanced tumors. Early diagnosis, including the detection of lesions at risk for malignant transformation, is crucial for limiting the need for extensive surgery and for improving disease-free survival. Saliva has gained popularity as a readily available source of biomarkers (including cytokines) useful for diagnosing specific oral and systemic conditions. Particularly, the close interaction between oral dysplastic/neoplastic cells and saliva makes such fluid an ideal candidate for the development of non-invasive and highly accurate diagnostic tests. The present review has been designed to answer the question: "Is there evidence to support the role of specific salivary cytokines in the diagnosis of OSCC?" We retrieved 27 observational studies satisfying the inclusion and exclusion criteria. Among the most frequent cytokines investigated as candidates for OSCC biomarkers, IL-6, IL-8, TNF-α are present at higher concentration in the saliva of OSCC patients than in healthy controls and may therefore serve as basis for the development of rapid tests for early diagnosis of oral cancer.


Assuntos
Biomarcadores , Carcinoma de Células Escamosas/metabolismo , Citocinas/metabolismo , Neoplasias Bucais/metabolismo , Saliva/metabolismo , Biomarcadores Tumorais , Carcinoma de Células Escamosas/diagnóstico , Humanos , Biópsia Líquida/métodos , Neoplasias Bucais/diagnóstico , Prognóstico
3.
Vox Sang ; 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34156107

RESUMO

BACKGROUND AND OBJECTIVES: The first wave of coronavirus disease-2019 (COVID-19) dramatically affected the Transfusion Medicine Unit of the Azienda Unità Sanitari Locale - Istituto di Ricovero e Cura a Carattere Scientifico (AUSL-IRCCS) di Reggio Emilia, which faced a total rearrangement of the procedures for donors and patients. This study aims to assess the major implications of COVID-19 on our department, focusing on the blood transfusion chain and therapies, in order to support transfusion specialists in seeking efficient ways to face similar future emergencies. MATERIALS AND METHODS: This retrospective study compares our Transfusion Medicine Unit data collected between February and May 2020 with the same period in 2017-2019. Data on red blood cells and platelets donations, transfusions and clinical procedures were collected as aggregates from our internal electronic database. RESULTS: During the lockdown, donor centres were re-organized to reduce the risk of contagion and avoid unnecessary blood collection. Blood donations were re-scheduled to meet the decrease in elective surgery; consequently, plateletapheresis was implemented to supply the reduction of buffycoat-derived platelets. Transfusions significantly decreased together with orthopaedic and vascular surgery, while they were only marginally diminished for both cancer and onco-haematological patients. Reduced procedures for inpatients and outpatients were matched by remote medicine, addressing the need of a constant healthcare support for patients with chronic diseases. CONCLUSIONS: The described measures were adopted to avoid excessive blood collection and expiration, guarantee the safety of our ward (for both patients and staff) and supply the necessary transfusion therapies. These measures may support the development of appropriate risk management plans and safety procedures for other hospitals and transfusion services that have to face similar events.

4.
Transfus Apher Sci ; 60(4): 103155, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33975808

RESUMO

Allogeneic peripheral blood-derived (PBS) serum eye drops have been largely used in the treatment of dry eye disease (DED). Recently, cord blood has emerged as an effective alternative serum source (cord blood serum, CBS), containing a higher amount of growth factors than PBS, it holds the promise of a better capability to stimulate corneal healing. However, the lack of a standardized method for preparation, dispensation, storage and a poor biochemical characterization still hamper the establishment of a clinical consensus. Here the metabolomes of the two different serum eye drop preparations were compared using proton nuclear magnetic resonance spectroscopy. We found that both PBS and CBS contained several organic compounds, the majority of them already detected in human tears and may be thereby considered lacrimal substitutes. Metabolites having in the multivariate statistical analysis Partial least squares discriminant analysis (PLS-DA) a VIP scores > 1.0 were considered to be significantly different. All the metabolites identified were found to have a p < 0.05 in the univariate analysis. CBS, in particular, showed the highest amount of choline, myo-inositol, glutamine, creatine and ß-hydroxybutyrate. These evidences constitute relevant advances towards serum eye drops characterization and confirm that cord blood is a valid alternative source of serum eye drops.

5.
J Fungi (Basel) ; 7(2)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578728

RESUMO

The previously described decapeptide AKVTMTCSAS (killer peptide, KP), derived from the variable region of a recombinant yeast killer toxin-like anti-idiotypic antibody, proved to exert a variety of antimicrobial, antiviral, and immunomodulatory activities. It also showed a peculiar self-assembly ability, likely responsible for the therapeutic effect in animal models of systemic and mucosal candidiasis. The present study analyzed the biological and structural properties of peptides derived from KP by substitution or deletion of the first residue, leaving unchanged the remaining amino acids. The investigated peptides proved to exert differential in vitro and/or in vivo anti-Candida activity without showing toxic effects on mammalian cells. The change of the first residue in KP amino acidic sequence affected the conformation of the resulting peptides in solution, as assessed by circular dichroism spectroscopy. KP-derivatives, except one, were able to induce apoptosis in yeast cells, like KP itself. ROS production and changes in mitochondrial transmembrane potential were also observed. Confocal and transmission electron microscopy studies allowed to establish that selected peptides could penetrate within C. albicans cells and cause gross morphological alterations. Overall, the physical and chemical properties of the first residue were found to be important for peptide conformation, candidacidal activity and possible mechanism of action. Small antimicrobial peptides could be exploited for the development of a new generation of antifungal drugs, given their relative low cost and ease of production as well as the possibility of devising novel delivery systems.

6.
Biochim Biophys Acta Gen Subj ; 1865(5): 129843, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33444726

RESUMO

Among their various functions, the members of the cerato-platanin family can stimulate plants' defense responses and induce resistance against microbial pathogens. Recent results suggest that conserved loops, also involved in chitin binding, might be a structural motif central for their eliciting activity. Here, we focus on cerato-platanin and its orthologous cerato-populin, searching for a rationale of their diverse efficiency to elicit plants' defense and to interact with oligosaccharides. A 3D model of cerato-populin has been generated by homology modeling using the NMR-derived cerato-platanin structure as template, and it has been validated by fitting with residual dipolar couplings. Loops ß1-ß2 and ß2-ß3 have been indicated as important for some CPPs members to express their biological function. When compared to cerato-platanin, in cerato-populin they present two mutations and an insertion that significantly modify their electrostatic surface. NMR relaxation experiments point to a reduced conformational plasticity of cerato-populin loops with respect to the ones of cerato-platanin. The different electrostatic surface of the loops combined with a distinct network of intra-molecular interactions are expected to be factors that, by leading to a diverse spatial organization and dissimilar collective motions, can regulate the eliciting efficacy of the two proteins and their affinity for oligosaccharides.


Assuntos
Ceratocystis/metabolismo , Proteínas Fúngicas/metabolismo , Oligossacarídeos/metabolismo , Doenças das Plantas/microbiologia , Ceratocystis/química , Proteínas Fúngicas/química , Modelos Moleculares , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
7.
Transfus Apher Sci ; 60(1): 102963, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33051093

RESUMO

The AUSL-IRCCS of Reggio Emilia Transfusion Unit operates in two blood donor centers. Plasmapheresis protocols and machines are identical in both centers, except for the final unit weight setting: 700 g in Center 1 and 720 g in Center 2. Within a wider study to assess the anticoagulant content in plasma units through proton nuclear magnetic resonance, we compared the efficiency of the two settings. We analyzed 215 and 100 consecutive samples from Centers 1 and 2, respectively. We collected processed blood volume, net plasma collected and anticoagulant volume in the plasma units. In our experience, setting the machine at 720 g instead of 700 g was associated with a small increase in plasma content of the final unit (only 4 mL), but implied an increase of more than 100 mL of the total processed blood and a higher amount of anticoagulant in the unit. On the contrary, the difference in donor's reinfused anticoagulant was negligible. Our findings come from an observational study suggesting that, in view of a minimal advantage in terms of collected net plasma, there might be relevant disadvantages for the donor in prolonging plasmapheresis over 700 g. Since observed differences may be attributed to confounding factors, we recommend always checking the marginal efficiency of the procedure when the balance target value of the setting is increased. Randomized cross-over studies are needed to find the optimal target weight for plasma units. These studies could also help defining personalized plasmapheresis procedures, thus further optimizing donor safety.

8.
Blood Transfus ; 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33370225

RESUMO

BACKGROUND: Red blood cell (RBC) units may contain a variety of molecules that can activate the neutrophil cascade turning neutrophils into targets for immunomodulatory molecules. Our metabolomics profiling of RBC units revealed a significant increase of hypoxanthine concentration during storage. Hypoxanthine catabolism in vivo ends with the production of uric acid through a reaction catalysed by xanthine oxidase during which reactive oxygen species are generated. Some authors have described in vitro neutrophil activation after treatment with stored RBC medium. However, the response of neutrophils to the action of xanthine oxidase upon hypoxanthine accumulation in the supernatant of RBC units has never been investigated. MATERIALS AND METHODS: Neutrophils were isolated from peripheral whole blood and cultured at 37 °C in a humidified incubator with 5% CO2. Hypoxanthine and RBC supernatants were tested to verify neutrophil stimulation. To prove the involvement of hypoxanthine in neutrophil activation, xanthine oxidase was pre-incubated with or without allopurinol before addition to the neutrophil cultures. Intracellular expression of tumour necrosis factor-α (TNF-α) and interleukin-8 (IL-8) was assessed by a cytofluorimetric assay and early-stage release of IL-8 was detected by a Luminex® assay. RESULTS: In the presence of xanthine oxidase, hypoxanthine, alone and in combination with RBC supernatants, caused increases of TNF-α- and IL-8-positive cells after 5 hours of treatment. Moreover, IL-8 was quickly released, 30 min after stimulation. DISCUSSION: Here we show, for the first time, that neutrophil activation by stored RBC depends, in part, on the presence of hypoxanthine contained in the RBC units. Our results add hypoxanthine to the already known mediators of inflammation present in RBC units, supporting the evidence that medium from stored RBC may concur to boost inflammatory processes in transfusion recipients, potentially leading to negative post-transfusion outcomes.

9.
Blood Transfus ; 18(5): 359-365, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32931414

RESUMO

BACKGROUND: While patient blood management (PBM) principles are not specific to cancer patients, their application contains the pathophysiological premises that could also benefit this patient population. In this study, we assessed the effects of implementing a PBM bundle for cancer patients in the postoperative period. MATERIALS AND METHODS: The Azienda USL-IRCCS of Reggio Emilia implemented a two-step PBM bundle for the postoperative period of cancer patients hospitalised in the semi-intensive post-surgery (SIPO) ward. Step 1 included seminars and lessons specifically targeting SIPO personnel; Step 2 introduced Points of Care (POCs) for the continuous monitoring of haemoglobin (Radical7, Masimo Corp, Irvine, CA, USA). We conducted 3 audits on 600 cancer patients recruited between 2014 and 2017: Audit 1 on 200 patients before the application of our PBM bundle; Audit 2 after Step 1 on 200 patients; Audit 3 after Step 2 on 200 patients monitored with POCs. Red blood cell (RBC) transfusion appropriateness in the postoperative period was evaluated using the Italian Society of Transfusion Medicine and Immunohaematology (SIMTI) recommendations. RESULTS: RBC transfusion appropriateness in the postoperative period of cancer patients rose from 38% to 75% after seminars, and reached 79% after the introduction of POC. The mean number of RBC units each patient received remained unchanged after training sessions (1.8 units/patient) while the introduction of POCs saw a simultaneous decrease in the number of prescribed units (1.3 units/patient). DISCUSSION: Our PBM bundle positively impacted RBC transfusion appropriateness in postsurgical cancer patients, both in terms of quality and quantity. A structured PBM programme specifically dedicated to surgical oncology should cover the entire perioperative period and might further improve transfusion appropriateness in these patients. The publication of guidelines on the management of anaemia in surgical oncology should be a priority.


Assuntos
Perda Sanguínea Cirúrgica , Transfusão de Eritrócitos , Auditoria Médica , Neoplasias/cirurgia , Cuidados Pós-Operatórios , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Período Pós-Operatório
10.
Metabolites ; 10(8)2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32781584

RESUMO

The detection of salivary molecules associated with pathological and physiological alterations has encouraged the search of novel and non-invasive diagnostic biomarkers for oral health evaluation. While genomic, transcriptomic, and proteomic profiles of human saliva have been reported, its metabolic composition is a topic of research: metabolites in submandibular/sublingual saliva have never been analyzed systematically. In this study, samples of whole, parotid, and submandibular/sublingual saliva from 20 healthy donors, without dental or periodontal diseases, were examined by nuclear magnetic resonance. We identified metabolites which are differently distributed within the three saliva subtypes (54 in whole, 49 in parotid, and 36 in submandibular/sublingual saliva). Principal component analysis revealed a distinct cluster for whole saliva and a partial overlap for parotid and submandibular/sublingual metabolites. We found exclusive metabolites for each subtype: 2-hydroxy-3-methylvalerate, 3-methyl-glutarate, 3-phenylpropionate, 4-hydroxyphenylacetate, 4-hydroxyphenyllactate, galactose, and isocaproate in whole saliva; caprylate and glycolate in submandibular/sublingual saliva; arginine in parotid saliva. Salivary metabolites were classified into standard and non-proteinogenic amino acids and amines; simple carbohydrates; organic acids; bacterial-derived metabolites. The identification of a salivary gland-specific metabolic composition in healthy people provides the basis to invigorate the search for salivary biomarkers associated with oral and systemic diseases.

11.
Blood Transfus ; 18(3): 170-175, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32281927

RESUMO

BACKGROUND: Anticoagulant concentration in plasma units is extremely variable. Understanding the underlying causes of this variability could help personalise plasmapheresis procedures in order to optimise the risk-benefit ratio. We studied the association between anticoagulant solution A (usually ACD-A, Citrate Dextrose Solution A) volume in plasma units and donor characteristics to build a model to determine the needed weight of the final plasma unit to have an 80% probability of reaching 600 mL net plasma. MATERIALS AND METHODS: We experimentally measured ACD-A in 296 plasma units from an Italian blood donor centre, where machines are set for the collection of 700 g of plasma. Next, we built a statistical model to predict how the final volume of the unit should be set to obtain 50%, 80% or 90% probability of having at least 600 mL net plasma. RESULTS: ACD-A volume was associated with haemoglobin, total proteins and triglycerides. Donors with low haemoglobin reach an 80% probability of at least 600 mL net plasma with units of approximately 690 g, while 720 g are needed for donors with high haemoglobin levels. For total proteins and triglycerides, plasma units may vary within a range of ±20 g. DISCUSSION: Our model, based on easily measurable individual characteristics, makes it possible to customise plasmapheresis procedures by determining the blood volume to be processed for each donor. Tailored plasma donations might result in both a reduction in adverse events and an increase in the quality of collected plasma.


Assuntos
Doadores de Sangue , Modelos Biológicos , Plasma , Plasmaferese , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
J Clin Apher ; 35(3): 146-153, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32087045

RESUMO

Low-density lipoprotein (LDL) apheresis (LA) selectively eliminates lipoproteins containing apolipoprotein B 100 (ApoB100) on patients affected by severe dyslipidemia. In addition to lowering lipids, LA is thought to exert pleiotropic effects altering a number of other compounds associated with atherosclerosis, such as pro- and anti-inflammatory cytokines or pro-thrombotic factors. More knowledge needs to be gathered on the effects of LA, and particularly on its ability to modify blood components other than lipids. We performed a multiparametric assessment of the inflammatory, metabolic and proteomic profile changes after Heparin-induced lipoprotein precipitation (H.E.L.P.) apheresis on serum samples from nine dyslipidemic patients evaluating cholesterol and lipoproteins, plasma viscosity and density, metabolites, cytokines, PCSK9 levels and other proteins selectively removed after the treatment. Our results show that H.E.L.P. apheresis is effective in lowering lipoprotein and PCSK9 levels. Although not significantly, complement and inflammation-related proteins are also affected, indicating a possible transient epiphenomenon induced by the extracorporeal procedure.

13.
Int J Mol Sci ; 21(3)2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32019170

RESUMO

: Background: The aberrant expression of microRNAs (miRNAs) has been associated with several diseases, including cancer, inflammatory, and autoimmune conditions. Interest in salivary miRNAs as non-invasive tools for the diagnosis of malignancies and systemic diseases is rapidly increasing. The present systematic review was developed for answering the question: "Are salivary microRNAs reliable biomarkers for diagnosis of cancer and systemic diseases?" METHODS: The application of inclusion and exclusion criteria led to the selection of 11 papers. Critical appraisals and quality assessments of the selected studies were performed through the National Institute of Health "Study Quality Assessment Tool" and the classification of the Oxford Center for Evidence-Based Medicine. RESULTS: Seven studies reported statistically significant correlations between one or more salivary miRNAs and the investigated disease. The critical analysis allowed us to classify only two studies (18.2%) as having "good" quality, the rest being scored as "intermediate" (8; 73%) and "poor" (1; 9%). Evidence exists that salivary miR-940 and miR-3679-5p are reliable markers for pancreatic cancer and that miR140-5p and miR301a are promising molecules for the salivary diagnosis of gastric cancer. CONCLUSIONS: Further studies, possibly avoiding the risk of bias highlighted here, are necessary to consolidate these findings and to identify new reliable salivary biomarkers.


Assuntos
Doenças Autoimunes/diagnóstico , Biomarcadores/análise , Inflamação/diagnóstico , MicroRNAs/genética , Neoplasias/diagnóstico , Saliva/metabolismo , Doenças Autoimunes/genética , Doenças Autoimunes/metabolismo , Humanos , Inflamação/genética , Inflamação/metabolismo , Neoplasias/genética , Neoplasias/metabolismo
14.
Transfusion ; 59(6): 2113-2120, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30875439

RESUMO

BACKGROUND: To date, the quantification of the anticoagulant (ACD-A) in plasma units has been based on theoretical calculations. An accurate quantification could help minimize the risks associated with plasmapheresis, given that the total ACD-A used during the procedure is distributed between the donor and the plasma unit. Our aim was to experimentally quantify the volume of ACD-A in units collected by plasmapheresis. STUDY DESIGN AND METHODS: We used proton nuclear magnetic resonance spectroscopy to measure the ACD-A volume in 295 plasma units collected by the Azienda USL-IRCCS of Reggio Emilia, Italy. We analyzed the determinants of the differences between estimated and measured ACD-A through multivariate regression models. RESULTS: The experimentally measured ACD-A in plasma units was variable, with 45% of the samples showing a discrepancy of more than 15 mL compared to the manufacturer's estimate. ACD-A was underestimated for higher density of the units (p < 0.0005); a weak association was also observed with triglycerides (underestimated for higher levels, p = 0.015) and sex (overestimated in females, p = 0.008), but our model explained only 35% of the individual variability. CONCLUSION: The manufacturer's algorithms do not accurately estimate the ACD-A in units collected by plasmapheresis. Donor-related characteristics may affect ACD-A distribution between donor and plasma unit, thereby explaining the discrepancies between estimate and measurement. Errors in the estimate of the ACD-A actually received by donors could hamper studies on dose-response relationship between anticoagulant and adverse reactions. Our work should stimulate research on tailored procedures aimed at minimizing the anticoagulant received by donors and increasing plasmapheresis safety.


Assuntos
Anticoagulantes/análise , Plasma/química , Plasmaferese , Adulto , Doadores de Sangue , Coleta de Amostras Sanguíneas/métodos , Feminino , Humanos , Itália , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Plasmaferese/métodos
15.
PLoS One ; 14(2): e0212447, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30789942

RESUMO

The increasing emergence of multidrug-resistant microorganisms represents one of the greatest challenges in the clinical management of infectious diseases, and requires the development of novel antimicrobial agents. To this aim, we de novo designed a library of Arg-rich ultra-short cationic antimicrobial lipopeptides (USCLs), based on the Arg-X-Trp-Arg-NH2 peptide moiety conjugated with a fatty acid, and investigated their antibacterial potential. USCLs exhibited an excellent antimicrobial activity against clinically pathogenic microorganisms, in particular Gram-positive bacteria, including multidrug resistant strains, with MIC values ranging between 1.56 and 6.25 µg/mL. The capability of the two most active molecules, Lau-RIWR-NH2 and Lau-RRIWRR-NH2, to interact with the bacterial membranes has been predicted by molecular dynamics and verified on liposomes by surface plasmon resonance. Both compounds inhibited the growth of S. aureus even at sub MIC concentrations and induced cell membranes permeabilization by producing visible cell surface alterations leading to a significant decrease in bacterial viability. Interestingly, no cytotoxic effects were evidenced for these lipopeptides up to 50-100 µg/mL in hemolysis assay, in human epidermal model and HaCaT cells, thus highlighting a good cell selectivity. These results, together with the simple composition of USCLs, make them promising lead compounds as new antimicrobials.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Desenho de Fármacos , Anti-Infecciosos/toxicidade , Peptídeos Catiônicos Antimicrobianos/toxicidade , Arginina/química , Resistência Microbiana a Medicamentos , Resistência a Múltiplos Medicamentos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Oligopeptídeos/química , Oligopeptídeos/farmacologia , Biblioteca de Peptídeos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/ultraestrutura
16.
Int J Mol Sci ; 19(12)2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30487461

RESUMO

The synthetic peptide T11F (TCRVDHRGLTF), derived from the constant region of human IgM antibodies, proved to exert a significant activity in vitro against yeast strains, including multidrug resistant isolates. Alanine substitution of positively charged residues led to a decrease in candidacidal activity. A more dramatic reduction in activity resulted from cysteine replacement. Here, we investigated the conformational properties of T11F and its alanine-substituted derivatives by circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy. Peptide interaction with Candida albicans cells was studied by confocal and scanning electron microscopy. T11F and most of its derivatives exhibited CD spectra with a negative band around 200 nm and a weaker positive band around 218 nm suggesting, together with NMR coupling constants, the presence of a polyproline II (PPII) helix, a conformational motif involved in a number of biological functions. Analysis of CD spectra revealed a critical role for phenylalanine in preserving the PPII helix. In fact, only the F11A derivative presented a random coil conformation. Interestingly, the loss of secondary structure influenced the rate of killing, which turned out to be significantly reduced. Overall, the obtained results suggest that the PPII conformation contributes in characterising the cell penetrating and fungicidal properties of the investigated peptides.


Assuntos
Anticorpos/química , Peptídeos Penetradores de Células/química , Fungicidas Industriais/química , Peptídeos/química , Candida albicans/efeitos dos fármacos , Peptídeos Penetradores de Células/farmacologia , Dicroísmo Circular , Fungicidas Industriais/farmacologia , Microscopia Confocal , Microscopia Eletrônica de Varredura , Ressonância Magnética Nuclear Biomolecular , Peptídeos/farmacologia
17.
Ann Hematol ; 97(10): 1909-1917, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29881883

RESUMO

The upholding of red blood cells (RBC) quality and the removal of leukocytes are two essential issues in transfusion therapy. Leukodepletion provides optimum results, nonetheless there are cases where irradiation is recommended for some groups of hematological patients such as the ones with chronic graft-vs-host disease, congenital cellular immunodeficiency, and hematopoietic stem cell transplant recipients. The European guidelines suggest irradiation doses from 25 to 50 Gray (Gγ). We evaluated the effect of different prescribed doses (15 to 50 Gγ) of X-ray irradiation on fresh leukodepleted RBCs bags using a novel protocol that provides a controlled irradiation. Biochemical assays integrated with RBCs metabolome profile, assessed by nuclear magnetic resonance spectroscopy, were performed on RBC units supernatant, during 14 days storage. Metabolome analysis evidenced a direct correlation between concentration increase of three metabolites, glycine, glutamine and creatine, and irradiation dose. Higher doses (35 and 50 Gγ) effect on RBC mean corpuscular volume, hemolysis, and ammonia concentration are considerable after 7 and 14 days of storage. Our data show that irradiation with 50 Gγ should be avoided and we suggest that 35 Gγ should be the upper limit. Moreover, we suggest for leukodepleted RBCs units the irradiation with the prescribed dose of 15 Gγ, value at center of bag, and ranging between 13.35-15 Gγ, measured over the entire bag volume, may guarantee the same benefits of a 25 Gγ dose assuring, in addition, a better quality of RBCs.


Assuntos
Eritrócitos/metabolismo , Eritrócitos/efeitos da radiação , Metaboloma/efeitos da radiação , Raios X , Adulto , Preservação de Sangue/métodos , Transplante de Medula Óssea/métodos , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Transfusão de Eritrócitos/métodos , Doença Enxerto-Hospedeiro/prevenção & controle , Humanos , Leucemia/terapia , Masculino , Pessoa de Meia-Idade , Doses de Radiação
19.
Laryngoscope ; 127(10): 2375-2381, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28224621

RESUMO

OBJECTIVES/HYPOTHESIS: Sudden sensorineural hearing loss (SSHL) is an otologic emergency that affects five to 30 subjects per 100,000/year. The cause of SSHL remains unknown or uncertain in 70% to 90% of cases, and treatment decisions are usually made without knowing the etiology. STUDY DESIGN: Prospective case-control study. METHODS: One hundred thirty-one idiopathic SSHL patients were recruited from January 2014 to June 2015 in concordance with the Statements of Clinical Practice Guideline and divided into groups according to the disease severity. A clinical laboratory assessment was completed on blood samples collected from SSHL patients and control subjects. Multivariable regression analysis was performed to investigate the association between laboratory data and SSHL basis. RESULTS: Only a few SSHL patients were positive for autoimmunity or viral infection. Statistically significant (P < .05) higher levels of blood glucose, glycated hemoglobin (HbA1C), lipoprotein (a), and factor VIII were found in SSHL patients compared to controls. Furthermore, blood glucose, HbA1C, uric acid, factor VIII, and homocysteine were significantly associated to disease severity. CONCLUSIONS: Gluco-metabolic, lipidic, and coagulative laboratory data support the vascular hypothesis for SSHL and its severity. LEVEL OF EVIDENCE: 3b Laryngoscope, 127:2375-2381, 2017.


Assuntos
Biomarcadores/sangue , Perda Auditiva Neurossensorial/sangue , Perda Auditiva Súbita/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Audiometria , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Súbita/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco , Adulto Jovem
20.
J Enzyme Inhib Med Chem ; 31(sup4): 78-87, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27578398

RESUMO

Cysteine is a building block for many biomolecules that are crucial for living organisms. O-Acetylserine sulfhydrylase (OASS), present in bacteria and plants but absent in mammals, catalyzes the last step of cysteine biosynthesis. This enzyme has been deeply investigated because, beside the biosynthesis of cysteine, it exerts a series of "moonlighting" activities in bacteria. We have previously reported a series of molecules capable of inhibiting Salmonella typhimurium (S. typhymurium) OASS isoforms at nanomolar concentrations, using a combination of computational and spectroscopic approaches. The cyclopropane-1,2-dicarboxylic acids presented herein provide further insights into the binding mode of small molecules to OASS enzymes. Saturation transfer difference NMR (STD-NMR) was used to characterize the molecule/enzyme interactions for both OASS-A and B. Most of the compounds induce a several fold increase in fluorescence emission of the pyridoxal 5'-phosphate (PLP) coenzyme upon binding to either OASS-A or OASS-B, making these compounds excellent tools for the development of competition-binding experiments.


Assuntos
Ciclopropanos/farmacologia , Cisteína Sintase/antagonistas & inibidores , Ácidos Dicarboxílicos/farmacologia , Inibidores Enzimáticos/farmacologia , Fluorometria , Ciclopropanos/síntese química , Ciclopropanos/química , Cisteína Sintase/química , Cisteína Sintase/metabolismo , Ácidos Dicarboxílicos/síntese química , Ácidos Dicarboxílicos/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Espectroscopia de Ressonância Magnética , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
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