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1.
Mol Cell ; 66(2): 206-220.e9, 2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-28416140

RESUMO

Cells exposed to hypoxia experience replication stress but do not accumulate DNA damage, suggesting sustained DNA replication. Ribonucleotide reductase (RNR) is the only enzyme capable of de novo synthesis of deoxyribonucleotide triphosphates (dNTPs). However, oxygen is an essential cofactor for mammalian RNR (RRM1/RRM2 and RRM1/RRM2B), leading us to question the source of dNTPs in hypoxia. Here, we show that the RRM1/RRM2B enzyme is capable of retaining activity in hypoxia and therefore is favored over RRM1/RRM2 in order to preserve ongoing replication and avoid the accumulation of DNA damage. We found two distinct mechanisms by which RRM2B maintains hypoxic activity and identified responsible residues in RRM2B. The importance of RRM2B in the response to tumor hypoxia is further illustrated by correlation of its expression with a hypoxic signature in patient samples and its roles in tumor growth and radioresistance. Our data provide mechanistic insight into RNR biology, highlighting RRM2B as a hypoxic-specific, anti-cancer therapeutic target.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Neoplasias do Colo/enzimologia , Replicação do DNA , DNA de Neoplasias/biossíntese , Oxigênio/metabolismo , Ribonucleotídeo Redutases/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Apoptose , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias do Colo/radioterapia , Dano ao DNA , DNA de Neoplasias/genética , Feminino , Células HCT116 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Interferência de RNA , Tolerância a Radiação , Ribonucleosídeo Difosfato Redutase/metabolismo , Ribonucleotídeo Redutases/química , Ribonucleotídeo Redutases/genética , Fatores de Tempo , Transfecção , Carga Tumoral , Hipóxia Tumoral , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/genética , Ensaios Antitumorais Modelo de Xenoenxerto
2.
BMC Microbiol ; 24(1): 60, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373929

RESUMO

BACKGROUND: The impact of probiotic strains on host health is widely known. The available studies on the interaction between bacteria and the host are focused on the changes induced by bacteria in the host mainly. The studies determining the changes that occurred in the bacteria cells are in the minority. Within this paper, we determined what happens to the selected Bifidobacterium adolescentis and Bifidobacterium longum ssp. longum in an experimental environment with the intestinal epithelial layer. For this purpose, we tested the bacteria cells' viability, redox activity, membrane potential and enzymatic activity in different environments, including CaCo-2/HT-29 co-culture, cell culture medium, presence of inflammatory inductor (TNF-α) and oxygen. RESULTS: We indicated that the external milieu impacts the viability and vitality of bacteria. Bifidobacterium adolescentis decrease the size of the live population in the cell culture medium with and without TNF-α (p < 0.001 and p < 0.01 respectively). In contrast, Bifidobacterium longum ssp. longum significantly increased survivability in contact with the eukaryotic cells and cell culture medium (p < 0.001). Bifidobacterium adolescentis showed significant changes in membrane potential, which was decreased in the presence of eukaryotic cells (p < 0.01), eukaryotic cells in an inflammatory state (p < 0.01), cell culture medium (p < 0.01) and cell culture medium with TNF-α (p < 0.05). In contrast, Bifidobacterium longum ssp. longum did not modulate membrane potential. Instead, bacteria significantly decreased the redox activity in response to milieus such as eukaryotic cells presence, inflamed eukaryotic cells as well as the culture medium (p < 0.001). The redox activity was significantly different in the cells culture medium vs the presence of eukaryotic cells (p < 0.001). The ability to ß-galactosidase production was different for selected strains: Bifidobacterium longum ssp. longum indicated 91.5% of positive cells, whereas Bifidobacterium adolescentis 4.34% only. Both strains significantly reduced the enzyme production in contact with the eukaryotic milieu but not in the cell culture media. CONCLUSION: The environmental-induced changes may shape the probiotic properties of bacterial strains. It seems that the knowledge of the sensitivity of bacteria to the external environment may help to select the most promising probiotic strains, reduce research costs, and contribute to greater reproducibility of the obtained probiotic effects.


Assuntos
Bifidobacterium adolescentis , Bifidobacterium longum , Bifidobacterium , Probióticos , Humanos , Fator de Necrose Tumoral alfa , Células CACO-2 , Células Eucarióticas , Reprodutibilidade dos Testes , Bactérias
3.
Int J Mol Sci ; 23(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35328547

RESUMO

Ageing is accompanied by the inevitable changes in the function of the immune system. It provides increased susceptibility to chronic infections that have a negative impact on the quality of life of older people. Therefore, rejuvenating the aged immunity has become an important research and therapeutic goal. Yolkin, a polypeptide complex isolated from hen egg yolks, possesses immunoregulatory and neuroprotective activity. Considering that macrophages play a key role in pathogen recognition and antigen presentation, we evaluated the impact of yolkin on the phenotype and function of mouse bone marrow-derived macrophages of the BMDM cell line. We determined yolkin bioavailability and the surface co-expression of CD80/CD86 using flow cytometry and IL-6, IL-10, TGF-ß and iNOS mRNA expression via real-time PCR. Additionally, the impact of yolkin on the regulation of cytokine expression by MAPK and PI3K/Akt kinases was determined. The stimulation of cells with yolkin induced significant changes in cell morphology and an increase in CD80/CD86 expression. Using pharmaceutical inhibitors of ERK, JNK and PI3K/Akt, we have shown that yolkin is able to activate these kinases to control cytokine mRNA expression. Our results suggest that yolkin is a good regulator of macrophage activity, priming mainly the M1 phenotype. Therefore, it is believed that yolkin possesses significant therapeutic potential and represents a promising possibility for the development of novel immunomodulatory medicine.


Assuntos
Gema de Ovo , Ativação de Macrófagos , Idoso , Animais , Galinhas , Citocinas/metabolismo , Feminino , Humanos , Macrófagos/metabolismo , Camundongos , Peptídeos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Qualidade de Vida , RNA Mensageiro/metabolismo
4.
Br J Cancer ; 118(9): 1229-1237, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29540773

RESUMO

BACKGROUND: Metastatic spread is responsible for the majority of cancer-associated deaths. The tumour microenvironment, including hypoxia, is a major driver of metastasis. The aim of this study was to investigate the role of the E3 ligase WSB-1 in breast cancer biology in the context of the hypoxic tumour microenvironment, particularly regarding metastatic spread. METHODS: In this study, WSB-1 expression was evaluated in breast cancer cell lines and patient samples. In silico analyses were used to determine the impact of WSB-1 expression on distant metastasis-free survival (DMFS) in patients, and correlation between WSB1 expression and hypoxia gene expression signatures. The role of WSB-1 on metastasis promotion was evaluated in vitro and in vivo. RESULTS: High WSB1 expression was associated with decreased DMFS in ER-breast cancer and PR-breast cancer patients. Surprisingly, WSB1 expression was not positively correlated with known hypoxic gene expression signatures in patient samples. Our study is the first to show that WSB-1 knockdown led to decreased metastatic potential in breast cancer hormone receptor-negative models in vitro and in vivo. WSB-1 knockdown was associated with decreased metalloproteinase (MMP) activity, vascular endothelial growth factor (VEGF) secretion, and angiogenic potential. CONCLUSIONS: Our data suggests that WSB-1 may be an important regulator of aggressive metastatic disease in hormone receptor-negative breast cancer. WSB-1 could therefore represent a novel regulator and therapeutic target for secondary breast cancer in these patients.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas/fisiologia , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Células Cultivadas , Feminino , Regulação Neoplásica da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Células MCF-7 , Camundongos , Camundongos Nus , Metástase Neoplásica , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Análise de Sobrevida
5.
Pol Merkur Lekarski ; 45(270): 242-247, 2018 Dec 28.
Artigo em Polonês | MEDLINE | ID: mdl-30693910

RESUMO

Type 2 diabetes has long been called the epidemic of the XXI century. It is the most common type of diabetes. One of the main causes of premature mortality, primarily due to serious complications, which for many years, developing "deceitfully" and asymptomatic. Despite the dynamic growth of the pharmaceutical industry and diabetes care for all patients is not possible to achieve target glycemic index values. It is emphasized that in type 2 diabetes by lifestyle, proper diet and regular physical activity are non-pharmacological treatment methods for maintaining good health. In many scientific studies noted, the close relationship of systematic traffic with less risk of developing the disease. That is why ongoing search for alternative methods of conducting physical training in patients with type II diabetes that are both attractive, safe and providing the highest benefits. Exercise on rehabilitation - reconditioning tables can be an attractive alternative to influence the metabolic control in patients with type 2 diabetes. AIM: The aim of the study was to evaluate of the effectiveness of increased physical activity with the use of rehabilitation-reconditioning tables on selected parameters of carbohydrate management in patients with type 2 diabetes. MATERIALS AND METHODS: A group of 50 women during their stay at the sanatorium were examined in aspects of biochemical blood parameters - glucose and glycosylated hemoglobin on the first and last day of 15- days training session (with a Sunday break) on 8 rehabilitationreconditioning tables with a total duration of 64 minutes. In addition, daily fasting blood capillary glucose levels were measured. To assess the level of physical activity of respondents used the International Physical Activity Questionnaire (ang. International Physical Activity Questionnaire - IPAQ) in Polish, in a condensed form (IPAQ Short Form). RESULTS: The analysis of the study shows that exercise for rehabilitation and reconditioning tables are an effective non-pharmacological treatment of type 2 diabetes. The exercise cycle used on rehabilitation and reconditioning tables caused a reduction of glucose and glycated hemoglobin levels in treated people. CONCLUSIONS: The study showed that training on rehabilitation and reconditioning tables is an attractive alternative to exercise influence on metabolic control in patients with type 2 diabetes, characterized by low physical activity, high BMI. Due to age related problems, a different type of physical activity is often impossible to these patients.


Assuntos
Diabetes Mellitus Tipo 2 , Carboidratos da Dieta , Terapia por Exercício , Adulto , Glicemia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/reabilitação , Feminino , Hemoglobinas Glicadas , Humanos , Polônia
6.
J Cell Sci ; 127(Pt 14): 3039-51, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24928894

RESUMO

RhoJ is a Rho GTPase expressed in endothelial cells and tumour cells, which regulates cell motility, invasion, endothelial tube formation and focal adhesion numbers. This study aimed to further delineate the molecular function of RhoJ. Using timelapse microscopy RhoJ was found to regulate focal adhesion disassembly; small interfering RNA (siRNA)-mediated knockdown of RhoJ increased focal adhesion disassembly time, whereas expression of an active mutant (daRhoJ) decreased it. Furthermore, daRhoJ co-precipitated with the GIT-PIX complex, a regulator of focal adhesion disassembly. An interaction between daRhoJ and GIT1 was confirmed using yeast two-hybrid experiments, and this depended on the Spa homology domain of GIT1. GIT1, GIT2, ß-PIX (also known as ARHGEF7) and RhoJ all colocalised in focal adhesions and depended on each other for their recruitment to focal adhesions. Functionally, the GIT-PIX complex regulated endothelial tube formation, with knockdown of both GIT1 and GIT2, or ß-PIX phenocopying RhoJ knockdown. RhoJ-knockout mice showed reduced tumour growth and diminished tumour vessel density, identifying a role for RhoJ in mediating tumour angiogenesis. These studies give new insight into the molecular function of RhoJ in regulating cell motility and tumour vessel formation.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Adesões Focais/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Fatores de Troca de Nucleotídeo Guanina Rho/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Movimento Celular/fisiologia , Proteínas Ativadoras de GTPase/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfoproteínas/metabolismo , Transdução de Sinais
7.
Electrophoresis ; 37(15-16): 2235-47, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27196540

RESUMO

The number of foodborne intoxications caused by emetic Bacillus cereus isolates has increased significantly. As such, rapid and reliable methods to identify emetic strains appear to be clinically relevant. In this study, intact cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to differentiate emetic and non-emetic bacilli. The phyloproteomic clustering of 34 B. cereus emetic and 88 non-emetic isolates classified as B. cereus, Bacillus thuringiensis, Bacillus weihenstephanensis, and Bacillus mycoides, showed (i) a clear separation of both groups at a similarity level of 43%, and (ii) a high relatedness among the emetic isolates (similarity of 78%). Specifically, 83 mass peak classes were recognized in the spectral window range between m/z 4000 and 12 000 that were tentatively assigned to 41 protein variants based on a bioinformatic approach. Mass variation between the emetic and the non-emetic subsets was recorded for 27 of them, including ten ribosomal subunit proteins, for which inter-strain polymorphism was confirmed by gene sequencing. Additional peaks were assigned to other proteins such as small acid soluble proteins, cold shock proteins and hypothetical proteins, e.g., carbohydrate kinase. Moreover, the results were supported by in silico analysis of the biomarkers in 259 members of B. cereus group, including Bacillus anthracis, based on their whole-genome sequences. In conclusion, the proteomic profiling by MALDI-TOF MS is a promising and rapid method for pre-screening B. cereus to identify medically relevant isolates and for epidemiologic purposes.


Assuntos
Bacillus cereus/isolamento & purificação , Técnicas de Tipagem Bacteriana/métodos , Eméticos/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bacillus/isolamento & purificação , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Polimorfismo Genético , Proteômica/métodos , Análise de Sequência de DNA
8.
Microbiology (Reading) ; 161(Pt 1): 158-167, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25378561

RESUMO

Type II toxin-antitoxin systems (TAs) are bicistronic operons ubiquitous in prokaryotic genomes, displaying multilevel association with cell physiology. Various possible functions have been assigned to TAs, ranging from beneficial for their hosts, such as a stress response, dormancy and protection against genomic parasites, to detrimental or useless functions, such as selfish alleles. As there is a link between several Escherichia coli features (e.g. virulence, lifestyle) and the phylogeny of this species, we hypothesized a similar association with TAs. Using PCR we studied the distribution of 15 chromosomal and plasmidic type II TA loci in 84 clinical E. coli isolates in relation to their main phylogenetic groups (A, B1, B2 and D). In addition, we performed in silico searching of these TA loci in 60 completely sequenced E. coli genomes deposited in GenBank. The highest number of TA loci per strain was observed in group A (mean 8.2, range 5-12) and the lowest in group B2 (mean 4.2, range 2-8). Moreover, significant differences in the prevalence of nine chromosomal TAs among E. coli phylogroups were noted. In conclusion, the presence of some chromosomal TAs in E. coli is phylogroup-related rather than a universal feature of the species. In addition, their limited collection in group B2 clearly distinguish it from the other E. coli phylogroups.


Assuntos
Escherichia coli/classificação , Escherichia coli/genética , Genoma Bacteriano , Óperon , Filogenia , Bases de Dados de Ácidos Nucleicos , Escherichia coli/isolamento & purificação , Ordem dos Genes , Genes Bacterianos , Genômica , Humanos , Locos de Características Quantitativas
9.
Ginekol Pol ; 86(10): 774-81, 2015 Oct.
Artigo em Polonês | MEDLINE | ID: mdl-26677588

RESUMO

OBJECTIVES: The aim of the study was to evaluate the usefulness of US in the diagnosis of posterior fossa abnormalities in neonates by posterolateral fontanelle as compared with the anterior fontanelle approach and MRI. MATERIAL AND METHODS: US studies were performed on 1337 neonates, including 512 preterm infants, through the anterior and posterolateral fontanelles. Abnormalities were detected in 134 patients. Among them, abnormalities in posterior fossa were visualized with the posterolateral approach in 14 neonates. MR images were obtained in that subgrqup. RESULTS: The lesions consisted of cerebellar hemorrhage and congenital cerebellar malformations. Foci of hemorrhage were visualized by US in preterm neonates (n = 5), only through the posterolateral approach and on MRI. Dandy-Walker malformations (n = 2) were detected by US with both approaches and confirmed on MRI. In pontocerebellar hypoplasia (n =2), US with both approaches, showed hypoplastic cerebellar hemispheres and fluid in the posterior fossa. MRI, additionally visualized pontine hypoplasia. Fluid collection in the posterior fossa and translocation of cerebellar hemispheres were observed in the other 6 neonates by US with both approaches. MRI revealed arachnoid cysts (n = 2), mega cisterna magna (n = 3) and Blake's pouch (n = 1). CONCLUSIONS: US using posterolateral fontanelle is the method of choice for the diagnosis of cerebellar hemorrhage. These lesions are not visualized through anterior fontanelle. US visualization of the abnormal structures in some cerebellar malformations has similar effectiveness for both approaches. MRI plays the crucial role in identification and differential diagnosis of these malformations.


Assuntos
Doenças Cerebelares/diagnóstico por imagem , Fontanelas Cranianas/diagnóstico por imagem , Fossa Craniana Posterior/anormalidades , Fossa Craniana Posterior/diagnóstico por imagem , Doenças do Recém-Nascido/diagnóstico por imagem , Doenças do Prematuro/diagnóstico por imagem , Ecoencefalografia/métodos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Triagem Neonatal/métodos
10.
Ginekol Pol ; 86(5): 366-71, 2015 May.
Artigo em Polonês | MEDLINE | ID: mdl-26117975

RESUMO

INTRODUCTION: Complete heart block (third-degree atrioventricular block) is a defect of the conduction system of the heart, in which the impulse generated in the sinoatrial node does not propagate to the ventricles, and thus the latter contract independently of the atria. A third-degree atrioventricular block can be either congenital or acquired. In 60-70% of the cases, the congenital heart block results from destruction of the conduction system of the fetal heart by anti-Ro/SSA and anti-La/SSB antibodies present in maternal serum. The antibodies are synthesized in the course of autoimmune maternal conditions, most often systemic lupus erythematosus or rarer rheumatoid arthritis, dermatomyositis or Sjögren's syndrome. The complete block can occur as an isolated defect or be associated with structural anomalies of the fetal heart. MATERIAL AND METHODS: A total of five patients whose fetuses were diagnosed with the third-degree atrioventricular block have been hospitalized at the Department of Obstetrics, Medical University of Gdansk between 2012 and 2014. RESULTS: We present the data of the five patients, hospitalized at the Department of Obstetrics, Medical University of Gdansk, whose fetuses were diagnosed prenatally with the complete heart block. The cases differ in terms of etiology clinical outcome, and postnatal treatment. All data are presented in Table I. CONCLUSIONS: We emphasize the role of appropriate pregnancy management and careful monitoring of the fetal condition. From obstetrical perspective, it is important to monitor the condition of fetuses with the third-degree atrioventricular block ultrasonographically and echocardiographically; in turn, cardiotocography is less useful in this setting. Therefore, a non-reactive cardiotocographic tracing should not constitute an indication for a preterm delivery. An affected fetus should be delivered in a tertiary center for perinatal care that cooperates with a pediatric cardiology center. An efficient program for cardologic prenatal care and close cooperation between obstetricians, neonatologists, pediatric cardiologists, and cardiac surgeons constitute the key to a successful outcome.


Assuntos
Bloqueio Atrioventricular/congênito , Bloqueio Atrioventricular/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Terapias Fetais/métodos , Ultrassonografia Pré-Natal/métodos , Bloqueio Atrioventricular/tratamento farmacológico , Dexametasona/administração & dosagem , Ecocardiografia , Feminino , Doenças Fetais/tratamento farmacológico , Glucocorticoides/administração & dosagem , Humanos , Recém-Nascido , Polônia , Gravidez , Resultado da Gravidez , Resultado do Tratamento
11.
Dev Period Med ; 19(3 Pt 1): 277-82, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26958690

RESUMO

INTRODUCTION: Bleeding to the subgaleal space is a rare and often serious complication of childbirth. Delivery with the use of vacuum or forceps is considered as the main risk factor of subgaleal hemorrhage. Reports of other possible causes (including fetal ones) appear rarely. OBJECTIVES: The aim of this study is to present and analyze two unusual cases of bleeding to subgaleal space in neonates delivered through caesarean section, in whom two different concomitant hematologic problems were diagnosed. The authors demonstrate also the mechanisms leading to the formation of subgaleal hematoma as well as discuss the impact of the final diagnosis on the course of the perinatal period and the need to modify medical practice in a variety of clinical situations in both newborns and their mothers. MATERIAL AND METHODS: Authors present two consecutive cases of severe subgaleal hemorrhage. RESULTS: In the first newborn hemophilia was finally diagnosed. The second neonate was diagnosed with neonatal alloimmune thrombocytopenia. CONCLUSIONS: Subgaleal hemorrhage is a rare complication of delivery. In severe cases, other possible risks should be considered apart from the traumatic delivery only. An early identification of potential hematological risk factors can influence the effectiveness of the treatment and help to modify the follow-up of both the infant and its mother.


Assuntos
Transtornos Herdados da Coagulação Sanguínea/diagnóstico , Transtornos Herdados da Coagulação Sanguínea/fisiopatologia , Traumatismos Craniocerebrais/etiologia , Hematoma/etiologia , Hemorragia/etiologia , Trombocitopenia Neonatal Aloimune/diagnóstico , Trombocitopenia Neonatal Aloimune/fisiopatologia , Transtornos Herdados da Coagulação Sanguínea/terapia , Cesárea , Feminino , Humanos , Recém-Nascido , Masculino , Trombocitopenia Neonatal Aloimune/terapia
12.
Postepy Hig Med Dosw (Online) ; 68: 23-8, 2014 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-24491892

RESUMO

INTRODUCTION: The aim of the paper was to determine the antibacterial activity of four glass ionomer cements against bacteria of the genera Streptococcus and Lactobacillus. MATERIAL AND METHODS: Four capsulated glass ionomer cements were applied in the study: Fuji Triage (GC), Fuji IX (GC), Ketac Molar (3M Espe) and Ketac Silver (3M Espe). Four standard bacterial strains were used to assess the antibacterial activity of the studied cements: Streptococcus mutans, S. sanguis, S. salivarius and Lactobacillus casei. The antibacterial activity was determined by the agar diffusion method. The bacterial suspension was spread with a cotton swab on TSA plates. For each material six wells (7 mm diameter, 5 mm deep) were made with a cork borer. Each well was then filled with freshly prepared cements. The results were obtained by measuring the bacterial growth inhibition zone after 1, 2, 3 and 7 days. RESULTS: Fuji Triage cement inhibited the growth of all bacterial strains. Fuji IX cement demonstrated the most potent antibacterial activity against S. sanguis. Ketac Molar showed antibacterial activity against S. sanguis and S. salivarius, whereas Ketac Silver was efficient against S. mutans as well. Neither of the Ketac cements inhibited growth of the standard L. casei strain. DISCUSSION: Antibacterial activity of glass ionomer cements has attracted the interest of scientists in recent years. Most authors, including us, carried out experiments using the agar diffusion method and demonstrated antibacterial activity of glass ionomer cements. Different antibacterial activity of glass ionomer cements, observed in our study and studies of other authors, depended on the evaluated cement, bacterial strain and period of evaluation.


Assuntos
Antibacterianos/farmacologia , Cimentos de Ionômeros de Vidro/farmacologia , Lactobacillus/efeitos dos fármacos , Streptococcus/efeitos dos fármacos , Humanos
13.
Ginekol Pol ; 85(4): 283-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24834706

RESUMO

OBJECTIVES: To evaluate changes in myocardial contractility that occur after selective laser photocoagulation of communicating vessels (SLPCV) in fetuses from pregnancies complicated with twin-to-twin transfusion syndrome (TTTS). METHODS: The study included 51 pregnant women between 16 and 26 weeks of gestation who underwent SLPCV due to TTTS. Ultrasonography was performed before SLPCV and on postoperative day 1, 3(4) and 7. Fetal heart contractility in both fetuses was evaluated by determining the shortening fractions of the left and right ventricles (FS LV and FS RV), and the myocardial performance index (Tei-Index). RESULTS: There was a significant increase in postoperative FS LV and FS RV in recipients (from 35.7% to 44%, P = 0.037 and from 27.6% to 32.9%, P = 0.021, respectively). Pre-operative Tei-Index values for both the left (0.55) and right ventricle (0.6) were above normal. The mean postoperative Tei-Index for the left ventricle decreased significantly to 0.49 (P = 0.011), while no significant change was observed in the right ventricle (0.57). No significant differences between pre- and postoperative FS and Tei-Index values were noted in the donors. CONCLUSIONS: SLPCV is reflected by a significantly increased myocardial contractility in recipients.


Assuntos
Transfusão Feto-Fetal/cirurgia , Fotocoagulação a Laser/métodos , Contração Miocárdica/fisiologia , Gravidez de Gêmeos , Ultrassonografia Pré-Natal , Feminino , Morte Fetal/prevenção & controle , Coração Fetal/diagnóstico por imagem , Transfusão Feto-Fetal/diagnóstico por imagem , Idade Gestacional , Humanos , Gravidez , Segundo Trimestre da Gravidez , Função Ventricular Esquerda/fisiologia , Função Ventricular Direita/fisiologia
14.
Przegl Epidemiol ; 68(3): 435-41, 543-7, 2014.
Artigo em Inglês, Polonês | MEDLINE | ID: mdl-25391007

RESUMO

OBJECTIVES: The goal of this study was to evaluate the quantity and pattern of outpatient antibiotic use in Poland between 2004 and 2008 and to determine the trends in prescribing practice. To investigate the oral and parenteral outpatient antibiotic use in Poland. MATERIAL AND METHODS: Data concerning outpatient use of systemic antibiotics between 2004 and 2008 were obtained from Polish National Health Fund databases expressed as the number of defined daily doses (DDD) per 1000 inhabitants per day (DID) according to the international Anatomical Therapeutic Chemical ATC classification system of the World Health Organization (WHO, version 2009). RESULTS: Total outpatient antibiotic use in Poland varied from the lowest 17.88DID in 2004 to the highest 21.39DID in 2007. Penicillins (J01C) represented the most frequently prescribed antibiotics constituting more than 50% of the total outpatient antibiotic use. The other most popular groups of antibiotics were tetracyclines (J01A), macrolides (J01F). On the fourth and fifth position were cephalosporins (J01D) and quinolones (J01M), respectively. The parenteral antibiotic use did not exceed 1% of the total outpatient antibiotics prescribed with cefuroxime being the most frequently prescribed drug. CONCLUSIONS: Total outpatient use of antibiotics in Poland in 2004-2008 was comparable to the median European level. The consumption of all antibiotics slightly increased from 2004 to 2007, and decreased in 2008. The most often prescribed antibiotics were penicillins, mainly amoxicillin and amoxicillin with enzyme inhibitor. During the study period the use of the older (narrow-spectrum) antibiotics decreased in favour of the newer (broad-spectrum) antibiotics. The results suggest the discrepancy between national recommendations and choice of antibiotics by physicians.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Pacientes Ambulatoriais/estatística & dados numéricos , Medicamentos sob Prescrição/uso terapêutico , Atenção Primária à Saúde/estatística & dados numéricos , Anti-Infecciosos/uso terapêutico , Cefalosporinas/uso terapêutico , Bases de Dados Factuais , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Macrolídeos/uso terapêutico , Masculino , Penicilinas/uso terapêutico , Polônia/epidemiologia , Estudos Retrospectivos , Tetraciclinas/uso terapêutico
15.
Int J Biol Macromol ; 274(Pt 2): 133415, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38925181

RESUMO

Highly stable, colloidal iron oxide nanoparticles with an oxyhydroxide-like surface were used as bacteria-capturing nano-baits. Peptidoglycan isolated from Listeria spp was used as bacteria polysaccharide model, and the nanoparticle binding was characterized showing a Langmuir isotherm constant, KL, equal to 50 ± 3 mL mg-1. The chemical affinity was further supported by dynamic light scattering, transmission electron microscopy, and infrared and UV-Vis data, pointing at the occurrence of extended, coordinative multiple point bindings. The interaction with Gram (+) (Listeria spp) and Gram (-) (Aeromonas veronii) bacteria was shown to be effective and devoid of any toxic effect. Moreover, a real sample, containing a population of several oligotrophic bacteria strains, was incubated with 1 g L-1 of nanoparticle suspension, in the absence of agitation, showing a 100 % capture efficiency, according to plate count. A nanoparticle regeneration method was developed, despite the known irreversibility of such bacterial-nanosurface binding, restoring the bacteria capture capability. This nanomaterial represents a competitive option to eliminate microbiological contamination in water as an alternative strategy to antibiotics, aimed at reducing microbial resistance dissemination. Finally, beyond their excellent features in terms of colloidal stability, binding performances, and biocompatibility this nanoparticle synthesis is cost effective, scalable, and environmentally sustainable.

16.
Cell Rep ; 43(2): 113707, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38306270

RESUMO

Diffuse intrinsic pontine gliomas (DIPGs) are deadly pediatric brain tumors, non-resectable due to brainstem localization and diffusive growth. Over 80% of DIPGs harbor a mutation in histone 3 (H3.3 or H3.1) resulting in a lysine-to-methionine substitution (H3K27M). Patients with DIPG have a dismal prognosis with no effective therapy. We show that histone deacetylase (HDAC) inhibitors lead to a significant reduction in the H3.3K27M protein (up to 80%) in multiple glioma cell lines. We discover that the SB939-mediated H3.3K27M loss is partially blocked by a lysosomal inhibitor, chloroquine. The H3.3K27M loss is facilitated by co-occurrence of H2A.Z, as evidenced by the knockdown of H2A.Z isoforms. Chromatin immunoprecipitation sequencing (ChIP-seq) analysis confirms the occupancy of H3.3K27M and H2A.Z at the same SB939-inducible genes. We discover a mechanism showing that HDAC inhibition in DIPG leads to pharmacological modulation of the oncogenic H3.3K27M protein levels. These findings show the possibility of directly targeting the H3.3K27M oncohistone.


Assuntos
Neoplasias Encefálicas , Glioma Pontino Intrínseco Difuso , Glioma , Humanos , Criança , Histonas , Proteínas Mutantes , Glioma/genética , Neoplasias Encefálicas/genética , Inibidores de Histona Desacetilases/farmacologia
17.
J Antimicrob Chemother ; 68(3): 610-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23134677

RESUMO

OBJECTIVES: We aim to develop antibacterial peptide mimics resistant to protease degradation, with broad-spectrum activity at sites of infection. METHODS: The bactericidal activities of LL-37, ceragenins CSA-13, CSA-90 and CSA-92 and the spermine-conjugated dexamethasone derivative D2S were evaluated using MIC and MBC measurements. Gingival fibroblast counting, interleukin-8 (IL-8) and lactate dehydrogenase (LDH) release from keratinocytes (HaCat) were used to determine effects on cell growth, pro-inflammatory response and toxicity. RESULTS: All tested cationic lipids showed stronger bactericidal activity than LL-37. Incubation of Staphylococcus aureus with half the MIC of LL-37 led to the appearance of bacteria resistant to its bactericidal effects, but identical incubations with CSA-13 or D2S did not produce resistant bacteria. Cathelicidin LL-37 significantly increased the total number of gingival fibroblasts, but ceragenins and D2S did not alter gingival fibroblast growth. Cationic lipids showed no toxicity to HaCat cells at concentrations resulting in bacterial killing. CONCLUSIONS: These data suggest that cationic lipids such as ceragenins warrant further testing as potential novel antibacterial agents.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Boca/microbiologia , Infecções Respiratórias/microbiologia , Adolescente , Bactérias/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos
18.
J Immunol ; 187(12): 6402-9, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22095714

RESUMO

In addition to its antibacterial activity, the cathelicidin-derived LL-37 peptide induces multiple immunomodulatory effects on host cells. Atomic force microscopy, F-actin staining with phalloidin, passage of FITC-conjugated dextran through a monolayer of lung epithelial cells, and assessment of bacterial outgrowth from cells subjected to Pseudomonas aeruginosa infection were used to determine LL-37's effect on epithelial cell mechanical properties, permeability, and bacteria uptake. A concentration-dependent increase in stiffness and F-actin content in the cortical region of A549 cells and primary human lung epithelial cells was observed after treatment with LL-37 (0.5-5 µM), sphingosine 1-phosphate (1 µM), or LPS (1 µg/ml) or infection with PAO1 bacteria. Other cationic peptides, such as RK-31, KR-20, or WLBU2, and the antibacterial cationic steroid CSA-13 did not reproduce the effect of LL-37. A549 cell pretreatment with WRW4, an antagonist of the transmembrane formyl peptide receptor-like 1 protein attenuated LL-37's ability to increase cell stiffness. The LL-37-mediated increase in cell stiffness was accompanied by a decrease in permeability and P. aeruginosa uptake by a confluent monolayer of polarized normal human bronchial epithelial cells. These results suggested that the antibacterial effect of LL-37 involves an LL-37-dependent increase in cell stiffness that prevents epithelial invasion by bacteria.


Assuntos
Peptídeos Catiônicos Antimicrobianos/fisiologia , Catelicidinas/fisiologia , Permeabilidade da Membrana Celular/imunologia , Inibição de Migração Celular/imunologia , Pulmão/imunologia , Pseudomonas aeruginosa/patogenicidade , Mucosa Respiratória/imunologia , Mucosa Respiratória/microbiologia , Sequência de Aminoácidos , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular/efeitos dos fármacos , Inibição de Migração Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Pulmão/citologia , Pulmão/efeitos dos fármacos , Dados de Sequência Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Mucosa Respiratória/efeitos dos fármacos
19.
Biomedicines ; 11(4)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37189653

RESUMO

Efforts to find therapeutic methods that support spinal cord functional regeneration continue to be desirable. Natural recovery is limited, so high hopes are being placed on neuromodulation methods which promote neuroplasticity, such as repetitive transcranial magnetic stimulation (rTMS) and electrical stimulation used as treatment options for managing incomplete spinal cord injury (iSCI) apart from kinesiotherapy. However, there is still no agreement on the methodology and algorithms for treatment with these methods. The search for effective therapy is also hampered by the use of different, often subjective in nature, evaluation methods and difficulties in assessing the actual results of the therapy versus the phenomenon of spontaneous spinal cord regeneration. In this study, an analysis was performed on the database of five trials, and the cumulative data are presented. Participants (iSCI patients) were divided into five groups on the basis of the treatment they had received: rTMS and kinesiotherapy (N = 36), peripheral electrotherapy and kinesiotherapy (N = 65), kinesiotherapy alone (N = 55), rTMS only (N = 34), and peripheral electrotherapy mainly (N = 53). We present changes in amplitudes and frequencies of the motor units' action potentials recorded by surface electromyography (sEMG) from the tibialis anterior-the index muscle for the lower extremity and the percentage of improvement in sEMG results before and after the applied therapies. The increase in values in sEMG parameters represents the better ability of motor units to recruit and, thus, improvement of neural efferent transmission. Our results indicate that peripheral electrotherapy provides a higher percentage of neurophysiological improvement than rTMS; however, the use of any of these additional stimulation methods (rTMS or peripheral electrotherapy) provided better results than the use of kinesiotherapy alone. The best improvement of tibialis anterior motor units' activity in iSCI patients provided the application of electrotherapy conjoined with kinesiotherapy and rTMS conjoined with kinesiotherapy. We also undertook a review of the current literature to identify and summarise available works which address the use of rTMS or peripheral electrotherapy as neuromodulation treatment options in patients after iSCI. Our goal is to encourage other clinicians to implement both types of stimulation into the neurorehabilitation program for subjects after iSCI and evaluate their effectiveness with neurophysiological tests such as sEMG so further results and algorithms can be compared across studies. Facilitating the motor rehabilitation process by combining two rehabilitation procedures together was confirmed.

20.
Biomedicines ; 11(10)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37892975

RESUMO

This study aimed to investigate the relationships between the different levels and degrees of incomplete spinal cord injury (iSCI) evaluated with magnetic resonance imaging (MRI) and the results of non-invasive electromyography (mcsEMG), motor-evoked potentials (MEP), and electroneurography (ENG). With a focus on patients with injuries at four different levels, C3-C5, C6-Th1, Th3-Th6, and Th7-L1, this research delved into the intricate interplay of spinal circuits and functional recovery. The study uses MEP, EMG, and ENG assessments to unveil the correlations between the MEP amplitudes and the MRI injury scores. We analysed data from 85 iSCI patients (American Spinal Injury Association-ASIA scale; ASIA C = 24, and D = 61). We compared the MRI and diagnostic neurophysiological test results performed within 1-2 months after the injury. A control group of 80 healthy volunteers was examined to establish reference values for the clinical and neurophysiological recordings. To assess the structural integrity of spinal white and grey matter on the transverse plane reconstructed from the sagittal readings, a scoring system ranging from 0 to 4 was established. The spinal cord was divided into two halves (left and right) according to the midline, and each half was further divided into two quadrants. Each quadrant was assessed separately. MEP and EMG were used to assess conduction in the corticospinal tract and the contraction properties of motor units in key muscles: abductor pollicis brevis (APB), rectus abdominis (RA), rectus femoris (RF), and extensor digitorum brevis muscles (EXT). We also used electroneurography (ENG) to assess peripheral nerve conduction and to find out whether the changes in this system significantly affect patients' scores and their neurophysiological status. The study revealed consistent positive correlations in iSCI patients between the bilateral decrease of the spinal half injury MRI scores and a decrease of the transcranially-evoked MEP amplitudes, highlighting the complex relationship between neural pathways and functional outcomes. Positive correlations are notably pronounced in the C3-C5, C6-Th1, and Th3-Th6 subgroups (mostly rs 0.5 and above with p < 0.05), while Th7-L1 presents distinct patterns (rs less than 0.5 and p being statistically insignificant) potentially influenced by unique structural compensation mechanisms. We also revealed statistically significant relationships between the decrease of the cumulative mcsEMG and MEP amplitudes and the cumulative ENG scores. These insights shed light on the multifaceted interactions between spinal cord injury levels, structural damage, neurophysiological measures, and motor function outcomes. Further research is warranted to unravel the intricate mechanisms driving these correlations and their implications for enhancing functional recovery and the rehabilitation algorithms in patients with iSCI.

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