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1.
Immunology ; 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38922694

RESUMO

Tuberculosis (TB) alone caused over a billion deaths in the last 200 years, making it one of the deadliest diseases to humankind. Understanding the immune mechanisms underlying protection or pathology in TB is key to uncover the much needed innovative approaches to tackle TB. The scavenger receptor cysteine-rich molecule CD5 antigen-like (CD5L) has been associated with TB, but whether and how CD5L shapes the immune response during the course of disease remains poorly understood. Here, we show an upregulation of CD5L in circulation and at the site of infection in C57BL/6 Mycobacterium tuberculosis-infected mice. To investigate the role of CD5L in TB, we studied the progression of M. tuberculosis aerosol infection in a recently described genetically engineered mouse model lacking CD5L. Despite the increase of CD5L during infection of wild-type mice, absence of CD5L did not impact bacterial burden, histopathology or survival of infected mice. Absence of CD5L associated with a modest increase in the numbers of CD4+ T cells and the expression of IFN-γ in the lungs of infected mice, with no major effect in overall immune cell dynamics. Collectively, this study confirms CD5L as a potential diagnostic biomarker to TB, showing no discernible impact on the outcome of the infection.

2.
Faraday Discuss ; 252(0): 468-479, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-38829129

RESUMO

Plastics are a cornerstone of the modern world, yet the durable material properties that we have come to depend upon have made them recalcitrant environmental pollutants. Biological solutions in the form of engineered enzymes offer low energy and sustainable approaches to recycle and upcycle plastic waste, uncoupling their production and end of life from fossil fuels and greenhouse gases. These enzymes however, encounter immense challenges acting on plastics: facing hydrophobic surfaces, molecular crowding, and high levels of substrate heterogeneity. There have been mixed reports about the benefits of fusing partner domains to polyethylene terephthalate (PET) degrading enzymes, with moderate improvements identified under specific conditions, but no clarity into the factors that underlie the mechanisms. Here, we use the SpyCatcher003:SpyTag003 technology, which demonstrates a profound 47 °C shift in Tm upon irreversible complex formation, to investigate the influence of the thermal stability of the fusion partner on a range of PETases selected for their optimal reaction temperatures. We find that the thermal stability of the fusion partner does not have a positive correlation on the activity of the enzymes or their evident kinetic and thermal stabilities. Instead, it appears that the fusion to less stable SpyCatcher003 tends to increase the measured activation energy of unfolding compared to the more stable complex and wildtype enzymes. Despite this, the fusions to SpyCatcher003 do not show significantly better catalytic activity on PET films, with or without SpyTag003, and were found to be sometimes disruptive. The approach we highlight here, in using a fusion partner with controllable melting temperature, allowed us to dissect the impact of the stability of a fusion partner on enzyme properties. Although fusion stability did not appear to be coupled with identifiable trends in enzymatic activities, careful analysis of the unfolding pathways, and solid and solution activities of a wider range of enzymes may yield a more detailed understanding.


Assuntos
Estabilidade Enzimática , Polietilenotereftalatos , Termodinâmica , Polietilenotereftalatos/química , Polietilenotereftalatos/metabolismo , Cinética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/genética
3.
Nat Commun ; 15(1): 4119, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750020

RESUMO

Sepsis results from systemic, dysregulated inflammatory responses to infection, culminating in multiple organ failure. Here, we demonstrate the utility of CD5L for treating experimental sepsis caused by cecal ligation and puncture (CLP). We show that CD5L's important features include its ability to enhance neutrophil recruitment and activation by increasing circulating levels of CXCL1, and to promote neutrophil phagocytosis. CD5L-deficient mice exhibit impaired neutrophil recruitment and compromised bacterial control, rendering them susceptible to attenuated CLP. CD5L-/- peritoneal cells from mice subjected to medium-grade CLP exhibit a heightened pro-inflammatory transcriptional profile, reflecting a loss of control of the immune response to the infection. Intravenous administration of recombinant CD5L (rCD5L) in immunocompetent C57BL/6 wild-type (WT) mice significantly ameliorates measures of disease in the setting of high-grade CLP-induced sepsis. Furthermore, rCD5L lowers endotoxin and damage-associated molecular pattern (DAMP) levels, and protects WT mice from LPS-induced endotoxic shock. These findings warrant the investigation of rCD5L as a possible treatment for sepsis in humans.


Assuntos
Proteínas Reguladoras de Apoptose , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos , Receptores Depuradores , Sepse , Animais , Camundongos , Ceco/cirurgia , Quimiocina CXCL1/metabolismo , Quimiocina CXCL1/genética , Modelos Animais de Doenças , Ligadura , Lipopolissacarídeos , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Fagocitose , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Proteínas Recombinantes/uso terapêutico , Proteínas Recombinantes/administração & dosagem , Sepse/imunologia , Sepse/tratamento farmacológico , Choque Séptico/imunologia , Proteínas Reguladoras de Apoptose/uso terapêutico , Receptores Depuradores/uso terapêutico
5.
J Crohns Colitis ; 17(10): 1624-1630, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37101357

RESUMO

BACKGROUND: Accurate tools to distinguish Crohn's disease [CD] from cryptoglandular disease in patients with perianal fistulas without detectable luminal inflammation on ileocolonoscopy and abdominal enterography (isolated perianal fistulas [IPF]) are lacking. We assessed the ability of video capsule endoscopy [VCE] to detect luminal inflammation in patients with IPF. METHODS: We studied consecutive adults [>17 years] with IPF who were evaluated by VCE after a negative ileocolonoscopy and abdominal enterography between 2013 and 2022. We defined luminal CD by VCE as diffuse erythema, three or more aphthous ulcers, or a Lewis score greater than 135. We compared rates of intestinal inflammation in this cohort with age- and sex-matched controls without perianal fistulas, who underwent VCE for other indications. We excluded persons with pre-existing inflammatory bowel disease [IBD] and exposure to non-steroidal anti-inflammatory drugs or immunosuppressive treatments. RESULTS: A total of 45 patients with IPF underwent VCE without complications. Twelve patients [26%] met our definition of luminal CD. Luminal CD was more common in patients with IPF than in controls [26% vs 3%; p <0.01]. Among patients with IPF, male sex (OR [odds ratio], 9.2; 95% confidence interval [CI] [1.1-79.4]), smoking (OR, 4.5; 95% CI [0.9-21.2]), abscess (OR, 6.3; 95% CI [1.5-26.8]), rectal enhancement on magnetic resonance imaging [MRI] (OR, 9.0; 95% CI [0.8-99.3]), and positive antimicrobial serology (OR, 7.1; 95% CI, [0.7-70.0]) were more common in those with a positive VCE study. CONCLUSIONS: VCE detected small intestinal inflammation suggestive of luminal CD in approximately one-quarter of patients with IPF. Larger studies are required to validate these findings.


Assuntos
Endoscopia por Cápsula , Doença de Crohn , Fístula , Fístula Retal , Adulto , Humanos , Masculino , Doença de Crohn/complicações , Doença de Crohn/diagnóstico , Imageamento por Ressonância Magnética , Inflamação/complicações , Fístula/complicações , Fístula Retal/diagnóstico por imagem , Fístula Retal/etiologia
6.
ChemSusChem ; 16(8): e202202277, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-36811288

RESUMO

Enzyme-based depolymerization is a viable approach for recycling of poly(ethylene terephthalate) (PET). PETase from Ideonella sakaiensis (IsPETase) is capable of PET hydrolysis under mild conditions but suffers from concentration-dependent inhibition. In this study, this inhibition is found to be dependent on incubation time, the solution conditions, and PET surface area. Furthermore, this inhibition is evident in other mesophilic PET-degrading enzymes to varying degrees, independent of the level of PET depolymerization activity. The inhibition has no clear structural basis, but moderately thermostable IsPETase variants exhibit reduced inhibition, and the property is completely absent in the highly thermostable HotPETase, previously engineered by directed evolution, which simulations suggest results from reduced flexibility around the active site. This work highlights a limitation in applying natural mesophilic hydrolases for PET hydrolysis and reveals an unexpected positive outcome of engineering these enzymes for enhanced thermostability.


Assuntos
Ácidos Ftálicos , Polietilenotereftalatos , Polietilenotereftalatos/química , Hidrolases , Ácidos Ftálicos/química , Etilenos
7.
Int. braz. j. urol ; 49(1): 89-96, Jan.-Feb. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1421709

RESUMO

ABSTRACT Introduction: Voiding diary (VD) is an important tool in the evaluation of children with voiding symptoms. Voiding frequency, maximal voided volume (MVV), average voided volume (AVV) and nocturnal volume (NV) can be extracted and are valuable in diagnosing and monitoring these disorders. Recently, ICCS has reduced the period of data recording on VD from 3 to 2 days. We hypothesized that one day voiding diary would be enough for guiding treatment. Materials and Methods: Children with overactive bladder (OAB) and primary monosymptomatic enuresis (PMNE) were oriented to fulfill a 3-day VD. Data obtained from VD were evaluated for the first day (1dVD), the first two days (2dVD), and all 3 days (3dVD) and compared according to the MVV, AVV, frequency, NV and expected bladder capacity (EBC). The Friedman, Student's t test and the Fisher's exact was used. ANOVA was used for multiple comparisons. We also used Pearson correlation test. Results: Ninety-eight children were included, 59 had PMNE and 30 OAB. Frequency, AVV and VN were similar regardless how many days the voiding episodes were recorded. Only MVV was higher by a mean of only 32 mL on 3dVD compared to 1dVD. A 1dVD has a sensitivity of 93,9% and a positive likelihood ratio of 2.2. As for the correlation of MVV and EBC it was observed that in 83% of children, MVV was lower than EBC. MVV corresponds to 67% and 69% of EBC in children with PMNE and OAB, respectively. Conclusion: We believe that 1dVD is sufficient to assess these children. It has a high sensitivity and good correlation to 3dVD in evaluating these children. Bladder capacity in this population, evaluated by maximum voided volume, was close to 68% of that obtained by the EBC.

8.
Front Immunol ; 12: 760770, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35003072

RESUMO

Since the pioneering discoveries, by the Nobel laureates Jules Hoffmann and Bruce Beutler, that Toll and Toll-like receptors can sense pathogenic microorganisms and initiate, in vertebrates and invertebrates, innate immune responses against microbial infections, many other families of pattern recognition receptors (PRRs) have been described. One of such receptor clusters is composed by, if not all, at least several members of the scavenger receptor cysteine-rich (SRCR) superfamily. Many SRCR proteins are plasma membrane receptors of immune cells; however, a small subset consists of secreted receptors that are therefore in circulation. We here describe the first characterization of biological and functional roles of the circulating human protein SSC4D, one of the least scrutinized members of the family. Within leukocyte populations, SSC4D was found to be expressed by monocytes/macrophages, neutrophils, and B cells, but its production was particularly evident in epithelial cells of several organs and tissues, namely, in the kidney, thyroid, lung, placenta, intestinal tract, and liver. Similar to other SRCR proteins, SSC4D shows the capacity of physically binding to different species of bacteria, and this opsonization can increase the phagocytic capacity of monocytes. Importantly, we have uncovered the capacity of SSC4D of binding to several protozoan parasites, a singular feature seldom described for PRRs in general and here demonstrated for the first time for an SRCR family member. Overall, our study is pioneer in assigning a PRR role to SSC4D.


Assuntos
Infecções Bacterianas/imunologia , Infecções por Protozoários/imunologia , Receptores de Reconhecimento de Padrão/imunologia , Receptores Depuradores Classe B/imunologia , Animais , Bactérias , Linhagem Celular , Células Epiteliais/imunologia , Humanos , Leishmania , Leucócitos/imunologia , Neospora , Fagocitose , Plasmodium berghei , Receptores de Reconhecimento de Padrão/química , Receptores de Reconhecimento de Padrão/genética , Proteínas Recombinantes/imunologia , Receptores Depuradores Classe B/química , Receptores Depuradores Classe B/genética , Trypanosoma brucei brucei
9.
Immunology ; 157(4): 296-303, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31162836

RESUMO

The characterization of the architecture, structure and extracellular interactions of the CD6 glycoprotein, a transmembrane receptor expressed in medullary thymocytes and all mature T-cell populations, has been enhanced by the existence of monoclonal antibodies (mAbs) that specifically recognize the various scavenger receptor cysteine-rich (SRCR) domains of the ectodomain. Using engineered isoforms of CD6 including or excluding each of the three SRCR domains, either expressed at the membranes of cells or in soluble forms, we provide conclusive and definitive evidence that domain 2 of CD6, previously not identifiable, can be recognized by the CD6 mAbs OX125 and OX126, and that OX124 targets domain 3 and can block the interaction at the cell surface of CD6 with its major ligand CD166. Alternative splicing-dependent CD6 isoforms can now be confidently identified. We confirm that following T-cell activation there is a partial replacement of full-length CD6 by the CD6Δd3 isoform, which lacks the CD166-binding domain, and we find no evidence for the expression of other CD6 isoforms at the mRNA or protein levels.


Assuntos
Processamento Alternativo/imunologia , Anticorpos Monoclonais Murinos/química , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Ativação Linfocitária , Linfócitos T/imunologia , Anticorpos Monoclonais Murinos/imunologia , Humanos , Células Jurkat , Domínios Proteicos , Isoformas de Proteínas/imunologia , Linfócitos T/citologia
10.
Ecancermedicalscience ; 12: 887, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30792804

RESUMO

INTRODUCTION AND AIMS: Splenic marginal zone lymphoma, an uncommon subtype of non-Hodgkin lymphoma (NHL), is usually present with symptomatic splenomegaly. Although splenectomy has long been considered the first-line therapy in symptomatic or cytopenic patients, it can lead to significant morbidity and mortality. Splenic irradiation is an option for patients who have a poor response to systemic therapy and/or are not surgical candidates. In this paper, we present a case report of a patient who received splenic radiotherapy for symptomatic splenomegaly. METHODS: An 85-year-old Caucasian man with a 4 year history of low-grade NHL presented with progressive pancytopenia, significant weight loss and symptomatic splenomegaly (abdominal discomfort, sense of fullness and limitation of mobility due to spleen size). The patient refused splenectomy and, in December 2017, was referred to palliative splenic radiotherapy. He was initially treated with five fractions of one Grey (Gy) in order to evaluate clinical and haematology response. After that, 1.5 Gy daily, 5 days a week for 3 weeks. 3D conformal radiotherapy, multiple fields and mixed energy (6 and 15 Mv) were used. RESULTS: Radiotherapy allowed significant splenic reduction to almost half the size, resolving abdominal discomfort and improving quality of life. There was no decline of haemoglobin, leukocytes and platelet counts; in fact, there was a marginal increase. CONCLUSION: Palliative splenic irradiation was well tolerated confirming that it is a safe treatment option for palliation of symptomatic splenomegaly. Thereby, splenic irradiation should be strongly considered in the management of symptomatic splenomegaly, for selected patients who are refractory to or unsuitable for other options or when the patient refuses other treatments.

11.
Front Immunol ; 7: 416, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27790215

RESUMO

The scavenger receptor cysteine-rich (SRCR) family comprises a group of membrane-attached or secreted proteins that contain one or more modules/domains structurally similar to the membrane distal domain of type I macrophage scavenger receptor. Although no all-inclusive biological function has been ascribed to the SRCR family, some of these receptors have been shown to recognize pathogen-associated molecular patterns (PAMP) of bacteria, fungi, or other microbes. SSc5D is a recently described soluble SRCR receptor produced by monocytes/macrophages and T lymphocytes, consisting of an N-terminal portion, which contains five SRCR modules, and a large C-terminal mucin-like domain. Toward establishing a global common role for SRCR domains, we interrogated whether the set of five SRCR domains of SSc5D displayed pattern recognition receptor (PRR) properties. For that purpose, we have expressed in a mammalian expression system the N-terminal SRCR-containing moiety of SSc5D (N-SSc5D), thus excluding the mucin-like domain likely by nature to bind microorganisms, and tested the capacity of the SRCR functional groups to physically interact with bacteria. Using conventional protein-bacteria binding assays, we showed that N-SSc5D had a superior capacity to bind to Escherichia coli strains RS218 and IHE3034 compared with that of the extracellular domains of the SRCR proteins CD5 and CD6 (sCD5 and sCD6, respectively), and similar E. coli-binding properties as Spα, a proven PRR of the SRCR family. We have further designed a more sensitive, real-time, and label-free surface plasmon resonance (SPR)-based assay and examined the capacity of N-SSc5D, Spα, sCD5, and sCD6 to bind to different bacteria. We demonstrated that N-SSc5D compares with Spα in the capacity to bind to E. coli and Listeria monocytogenes, and further that it can distinguish between pathogenic E. coli RS218 and IHE3034 strains and the non-pathogenic laboratory E. coli strain BL21(DE3). Our work thus advocates the utility of SPR-based assays as sensitive tools for the rapid screening of interactions between immune-related receptors and PAMP-bearing microbes. The analysis of our results suggests that SRCR domains of different members of the family have a differential capacity to interact with bacteria, and further that the same receptor can discriminate between different bacteria strains and species.

12.
J Pain Palliat Care Pharmacother ; 30(3): 201-5, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27491473

RESUMO

In palliative care, drugs are considered futile if they do not have a short-term benefit in symptom control or quality of life. The authors examined pharmacotherapy prescribed for patients referred to palliative care to identify futile drugs. This was a retrospective analysis of patients referred over 6 months, focusing on the prescription of gastric protectants, antidiabetic agents, bisphosphonates, anticoagulants, antidementia drugs, statins, and antihypertensive agents. The sample consisted of 448 patients. Gastric protectants were prescribed futilely in 50% of cases (125/248), statins in 97% (69/71), antihypertensive agents in 27% (42/155), antidiabetic drugs in 1% (1/70), bisphosphonates in 27% (4/15), and antidementia drugs in 100% (9/9). This study reveals that many patients with advanced cancer continue to be treated with inappropriate drugs and points to the need for medical training in palliative care, drawing attention to the need for therapeutic review at each medical visit.


Assuntos
Desprescrições , Futilidade Médica , Neoplasias/terapia , Cuidados Paliativos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Prescrição Inadequada/prevenção & controle , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Qualidade de Vida , Estudos Retrospectivos
13.
Eur J Immunol ; 46(6): 1490-503, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27005442

RESUMO

T lymphocytes stimulated through their antigen receptor (TCR) preferentially express mRNA isoforms with shorter 3´ untranslated regions (3´-UTRs) derived from alternative pre-mRNA cleavage and polyadenylation (APA). However, the physiological relevance of APA programs remains poorly understood. CD5 is a T-cell surface glycoprotein that negatively regulates TCR signaling from the onset of T-cell activation. CD5 plays a pivotal role in mediating outcomes of cell survival or apoptosis, and may prevent both autoimmunity and cancer. In human primary T lymphocytes and Jurkat cells we found three distinct mRNA isoforms encoding CD5, each derived from distinct poly(A) signals (PASs). Upon T-cell activation, there is an overall increase in CD5 mRNAs with a specific increase in the relative expression of the shorter isoforms. 3´-UTRs derived from these shorter isoforms confer higher reporter expression in activated T cells relative to the longer isoform. We further show that polypyrimidine tract binding protein (PTB/PTBP1) directly binds to the proximal PAS and PTB siRNA depletion causes a decrease in mRNA derived from this PAS, suggesting an effect on stability or poly(A) site selection to circumvent targeting of the longer CD5 mRNA isoform by miR-204. These mechanisms fine-tune CD5 expression levels and thus ultimately T-cell responses.


Assuntos
Antígenos CD5/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , MicroRNAs/genética , Poliadenilação , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Regiões 3' não Traduzidas , Sequência de Bases , Antígenos CD5/metabolismo , Regulação da Expressão Gênica , Humanos , Células Jurkat , Modelos Biológicos , Poli A , Interferência de RNA , Isoformas de RNA , RNA Mensageiro/genética
14.
PLoS One ; 10(9): e0138103, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26407005

RESUMO

Streptococcus agalactiae (or Group B Streptococcus, GBS) is a commensal bacterium present in the intestinal and urinary tracts of approximately 30% of humans. We and others previously showed that the PI-2a pilus polymers, made of the backbone pilin PilB, the tip adhesin PilA and the cell wall anchor protein PilC, promote adhesion to host epithelia and biofilm formation. Affinity-purified PI-2a pili from GBS strain NEM316 were recognized by N-acetylneuraminic acid (NeuNAc, also known as sialic acid) specific lectins such as Elderberry Bark Lectin (EBL) suggesting that pili are sialylated. Glycan profiling with twenty different lectins combined with monosaccharide composition by HPLC suggested that affinity-purified PI-2a pili are modified by N-glycosylation and decorated with sialic acid attached to terminal galactose. Analysis of various relevant mutants in the PI-2a pilus operon by flow-cytometry and electron microscopy analyses pointed to PilA as the pilus subunit modified by glycosylation. Double labeling using PilB antibody and EBL lectin, which specifically recognizes N-acetylneuraminic acid attached to galactose in α-2, 6, revealed a characteristic binding of EBL at the tip of the pilus structures, highly reminiscent of PilA localization. Expression of a secreted form of PilA using an inducible promoter showed that this recombinant PilA binds specifically to EBL lectin when produced in the native GBS context. In silico search for potentially glycosylated asparagine residues in PilA sequence pointed to N427 and N597, which appear conserved and exposed in the close homolog RrgA from S. pneumoniae, as likely candidates. Conversion of these two asparagyl residues to glutamyl resulted in a higher instability of PilA. Our results provide the first evidence that the tip PilA adhesin can be glycosylated, and suggest that this modification is critical for PilA stability and may potentially influence interactions with the host.


Assuntos
Adesinas Bacterianas/metabolismo , Proteínas de Fímbrias/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Processamento de Proteína Pós-Traducional , Streptococcus agalactiae , Adesinas Bacterianas/química , Adesinas Bacterianas/genética , Asparagina/química , Asparagina/genética , Asparagina/metabolismo , Aderência Bacteriana/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Fímbrias/química , Proteínas de Fímbrias/genética , Fímbrias Bacterianas/metabolismo , Fímbrias Bacterianas/ultraestrutura , Glucosiltransferases/metabolismo , Modelos Moleculares , Organismos Geneticamente Modificados , Lectinas de Plantas/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Inativadoras de Ribossomos/metabolismo , Streptococcus agalactiae/genética , Streptococcus agalactiae/metabolismo
15.
PLoS One ; 7(1): e29963, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22291899

RESUMO

Glyceraldehyde 3-phosphate dehydrogenases (GAPDH) are cytoplasmic glycolytic enzymes that, despite lacking identifiable secretion signals, have been detected at the surface of several prokaryotic and eukaryotic organisms where they exhibit non-glycolytic functions including adhesion to host components. Group B Streptococcus (GBS) is a human commensal bacterium that has the capacity to cause life-threatening meningitis and septicemia in newborns. Electron microscopy and fluorescence-activated cell sorter (FACS) analysis demonstrated the surface localization of GAPDH in GBS. By addressing the question of GAPDH export to the cell surface of GBS strain NEM316 and isogenic mutant derivatives of our collection, we found that impaired GAPDH presence in the surface and supernatant of GBS was associated with a lower level of bacterial lysis. We also found that following GBS lysis, GAPDH can associate to the surface of many living bacteria. Finally, we provide evidence for a novel function of the secreted GAPDH as an inducer of apoptosis of murine macrophages.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/farmacologia , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/farmacologia , Macrófagos/efeitos dos fármacos , Streptococcaceae/enzimologia , Animais , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Antígenos de Superfície/fisiologia , Apoptose/fisiologia , Aderência Bacteriana/fisiologia , Proteínas de Bactérias/análise , Proteínas de Bactérias/fisiologia , Extratos Celulares/química , Extratos Celulares/metabolismo , Células Cultivadas , Feminino , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Fímbrias Bacterianas/fisiologia , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/análise , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/fisiologia , Macrófagos/patologia , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Organismos Geneticamente Modificados , Ligação Proteica , Streptococcaceae/classificação , Streptococcaceae/crescimento & desenvolvimento , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/metabolismo , Infecções Estreptocócicas/patologia
16.
RBM rev. bras. med ; 60(5): 292-298, maio 2003. tab
Artigo em Português | LILACS | ID: lil-353672

RESUMO

As dermatoses inflamatórias representam uma das mais importantes afecçöes presentes na prática clínica ambulatorial diária. Nesta revisäo estaremos abordando os fenômenos envolvidos no mecanismo inflamatório, com especial atençäo a citocinas, e a participaçäo da pele como palco dessas transformaçöes fisiopatológicas. Juntamente a isto, estaremos abordando o importante papel dos corticosteróides na resoluçäo do processo inflamatório, com especial atençäo ao furoato de mometasona, devido à sua superior capacidade inibitória da gênese e liberaçäo de citocinas nas dermatoses córticosensíveis.(au)


Assuntos
Corticosteroides , Citocinas , Dermatopatias
17.
Rev. Col. Bras. Cir ; 26(2): 79-83, mar.-abr. 1999. tab
Artigo em Português | LILACS | ID: lil-271040

RESUMO

Foram analisadas retrospectivamente 26 pacientes gestantes traumatizadas, num período de nove anos. A média de idade foi 23,7 anos (16-42). A idade gestacional variou de dez a quarenta semanas (média 21,5 semanas), a maioria (46,1 por cento) no segundo trimestre. O mecanismo predominante (65,3 por cento) foi o trauma abdominal fechado por acidente automobilístico (atropelamento ou colisão). Na admissão, oito (30,7 por cento) pacientes apresentavam alterações hemodinâmicas. Seis doentes (23,0 por cento) apresentavam sangramento vaginal e, destas, quatro estavam hemodinamicamente normais. Analisamos a mortalidade materna, a mortalidade fetal e suas causas. Comparamos também a mediana dos valores do RTS e TRISS entre os grupos: sobrevida materno-fetal, sobrevida materna e óbito materno-fetal. Todas as gestantes admitidas com sangramento vaginal apresentaram óbito fetal. A mortalidade materna foi de 11,5 por cento, por choque hemorrágico. A mortalidade fetal foi de 30,7 por cento, sendo que 37,5 por cento destes óbitos foram provocados pela morte materna. A principal causa de mortalidade fetal foi o descolamento de placenta (50,0 por cento). Os índices de trauma, RTS e TRISS, foram significativamente menor (p=0,0025 e p<0,0001) no grupo óbito materno-fetal, porém esses índices não apresentaram valor prognóstico na mortalidade fetal


Assuntos
Mortalidade Fetal , Mortalidade Materna , Gravidez , Ferimentos e Lesões , Traumatismos Abdominais , Acidentes por Quedas
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