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1.
Biomater Adv ; 160: 213849, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599041

RESUMO

Spheroids derived from human mesenchymal stem cells (hMSCs) are of limited use for cartilage regeneration, as the viability of the cells progressively decreases during the period required for chondrogenic differentiation (21 days). In this work, spheroids based on hMSCs and a lactose-modified chitosan (CTL) were formed by seeding cells onto an air-dried coating of CTL. The polymer coating can inhibit cell adhesion and it is simultaneously incorporated into spheroid structure. CTL-spheroids were characterized from a morphological and biological perspective, and their properties were compared with those of spheroids obtained by seeding the cells onto a non-adherent surface (agar gel). Compared to the latter, smaller and more viable spheroids form in the presence of CTL as early as 4 days of culture. At this time point, analysis of stem cells differentiation in spheroids showed a remarkable increase in collagen type-2 (COL2A1) gene expression (~700-fold compared to day 0), whereas only a 2-fold increase was observed in the control spheroids at day 21. These results were confirmed by histological and transmission electron microscopy (TEM) analyses, which showed that in CTL-spheroids an early deposition of collagen with a banding structure already occurred at day 7. Overall, these results support the use of CTL-spheroids as a novel system for cartilage regeneration, characterized by increased cell viability and differentiation capacity within a short time-frame. This will pave the way for approaches aimed at increasing the success rate of procedures and reducing the time required for tissue regeneration.


Assuntos
Diferenciação Celular , Quitosana , Condrogênese , Lactose , Células-Tronco Mesenquimais , Esferoides Celulares , Quitosana/farmacologia , Quitosana/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Humanos , Diferenciação Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/citologia , Lactose/farmacologia , Lactose/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo II/metabolismo , Colágeno Tipo II/genética
2.
Nat Commun ; 11(1): 4994, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020485

RESUMO

Serogroup B meningococcus (MenB) is a leading cause of meningitis and sepsis across the world and vaccination is the most effective way to protect against this disease. 4CMenB is a multi-component vaccine against MenB, which is now licensed for use in subjects >2 months of age in several countries. In this study, we describe the development and use of an ad hoc protein microarray to study the immune response induced by the three major 4CMenB antigenic components (fHbp, NHBA and NadA) in individual sera from vaccinated infants, adolescents and adults. The resulting 4CMenB protein antigen fingerprinting allowed the identification of specific human antibody repertoire correlating with the bactericidal response elicited in each subject. This work represents an example of epitope mapping of the immune response induced by a multicomponent vaccine in different age groups with the identification of protective signatures. It shows the high flexibility of this microarray based methodology in terms of high-throughput information and minimal volume of biological samples needed.


Assuntos
Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Infecções Meningocócicas/imunologia , Vacinas Meningocócicas/imunologia , Neisseria meningitidis Sorogrupo B/imunologia , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Mapeamento de Epitopos , Humanos , Lactente , Infecções Meningocócicas/prevenção & controle , Biblioteca de Peptídeos , Análise Serial de Proteínas , Ensaios de Anticorpos Bactericidas Séricos , Adulto Jovem
3.
BMC Vet Res ; 15(1): 277, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375144

RESUMO

BACKGROUND: Little is known about the differences among adult and foetal equine mesenchymal stem cells (MSCs), and no data exist about their comparative ultrastructural morphology. The aim of this study was to describe and compare characteristics, immune properties, and ultrastructural morphology of equine adult (bone marrow: BM, and adipose tissue: AT) and foetal adnexa derived (umbilical cord blood: UCB, and Wharton's jelly: WJ) MSCs. RESULTS: No differences were observed in proliferation during the first 3 passages. While migration ability was similar among cells, foetal MSCs showed a higher adhesion ability, forming smaller spheroids after hanging drop culture (P < 0.05). All MSCs differentiated toward adipogenic, chondrogenic and osteogenic lineages, only tenogenic differentiation was less evident for WJ-MSCs. Data obtained by PCR confirmed MHC1 expression and lack of MHC2 expression in all four cell types. Foetal adnexa MSCs were positive for genes specific for anti-inflammatory and angiogenic factors (IL6, IL8, ILß1) and WJ-MSCs were the only positive for OCT4 pluripotency gene. At immunofluorescence all cells expressed typical mesenchymal markers (α-SMA, N-cadherin), except for BM-MSCs, which did not express N-cadherin. By transmission electron microscopy, it was observed that WJ-MSCs had a higher (P < 0.05) number of microvesicles compared to adult MSCs, and UCB-MSCs showed more microvesicles than BM-MSCs (P < 0.05). AT-MSCs had a lower number of mitochondria than WJ-MSCs (P < 0.05), and mitochondrial area was higher for WJ-MSCs compared to UCB and AT-MSCs (P < 0.05). CONCLUSIONS: Results demonstrate that MSCs from adult and foetal tissues have different characteristics, and foetal MSCs, particularly WJ derived ones, seem to have some charactestics that warrant further investigation into potential advantages for clinical application.


Assuntos
Células-Tronco Adultas/fisiologia , Sangue Fetal/citologia , Cavalos , Células-Tronco Mesenquimais , Geleia de Wharton/citologia , Animais , Diferenciação Celular , Ensaios de Migração Celular , Proliferação de Células , Senescência Celular
4.
Leg Med (Tokyo) ; 39: 1-8, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31078972

RESUMO

The estimation of the post mortem interval (PMI) is still one of the most challenging variables to determine and the different approaches currently used in its estimation generally yield to large post mortem windows. In the present study we combined morphological and immunohistochemical analysis in order to reach a more detailed knowledge on tissue organization and degradation after death. Ultrastructural cellular changes and the extracellular matrix of gingival tissues, collected at different post mortem intervals, were observed by a Transmission Electron Microscopy (TEM), in combination with the immunohistochemical detection of extracellular matrix proteins (i.e. collagen type I and collagen type III) as potential post mortem biochemical markers. The final goal was to find a correlation between morphological modifications, biomarkers expression and the time of death. Samples of gingival tissues obtained from 10 cadavers at different post mortem intervals (short post mortem interval, 1-3 days; mid post mortem interval, 4-6 days; long post mortem interval, 7-9 days) were processed for light microscopy and TEM and they were also immunostained with anti-collagen type I and type III antibodies. Results showed gradual degradation of extracellular matrix in the suboral connective tissue in relation to the different time of death. Moreover PMI was related to an increase of nuclear chromatin condensation and cytoplasmic vacuolization both in epithelial and connective tissues. In conclusion, in addition to traditional forensic approaches to estimate PMI, the combined analyses of cellular morphology, ultrastructure and immunohistochemical expression of collagen proteins allow to better infer the PMI.


Assuntos
Colágeno/metabolismo , Medicina Legal/métodos , Gengiva/metabolismo , Gengiva/patologia , Mudanças Depois da Morte , Tempo , Biomarcadores/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Fatores de Tempo
5.
Compr Psychiatry ; 70: 25-31, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27624420

RESUMO

BACKGROUND: Family history of suicidal behavior and suicide are both risk factors for suicide. However, the effects of family history of suicide versus suicide attempts on patient suicidal behavior remain unclear. The aim of the present study was to understand if family history of suicide as compared to family history of suicide attempts or no family history of suicidal behavior evidences different associations with suicidal behavior among psychiatric patients. METHOD: Participants included 157 female patients between the ages of 18 and 65years admitted at the Dr. Braulio A. Moyano Neuropsychiatric Women's Hospital. RESULTS: Seventy-nine patients (50.3%) reported no family history of suicidal behavior (NFHSB), while 78 patients (49.7%) reported a family history of suicidal behavior. Specifically, 41 patients (26.1%) reported a family history of suicide attempt (FHSA) and 37 patients (23.6%) reported a family history of suicide (FHS). These groups showed significant differences between family history of psychopathology and number of previous suicide attempts. Patients with an FHSA were more likely to present with a greater number of previous suicide attempts as compared to patients with NFHSB and FHS. CONCLUSION: There is an association between the number of suicide attempts and family history of suicide attempts in female patients hospitalized for suicidal behavior.


Assuntos
Saúde da Família , Ideação Suicida , Tentativa de Suicídio/psicologia , Suicídio/psicologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
6.
Transplant Proc ; 47(7): 2113-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26361656

RESUMO

INTRODUCTION: Since 2013, the regional network of transplantation centers "LAZIO TRANSPLANT" have adopted a new, mixed system for the allocation of liver grafts. METHODS: The organs from donors aged <65 are assigned to patients with higher Model for End-stage Liver Disease (MELD) scores on a common regional waiting list, whereas those from donors aged >65 are allocated to patients with higher MELD scores on a specific local waiting list (LWL) at each center, on a rotational basis. RESULTS: The new mixed allocation model grants a more rational allocation of the "standard" organs to the patients with the actual worst MELD score in the entire region, avoiding the possibility that a patient in relatively better clinical condition might be transplanted before a more severely ill patient on another center's waiting list. Nonstandard organs, presenting slightly increased transplant risks, are still allocated on a rotational basis among the different transplant centers, ensuring them the possibility to select, on the basis of a global clinical risk evaluation, those patients in their LWL whose MELD score would not grant any possibility to compete for the "standard" organ allocation. CONCLUSIONS: The application of the new model had no negative impact on the overall number of transplants performed or on the global list-satisfaction percentages, but has slightly improved the cumulative mortality of the patients in the waiting list, granting to the clinically worst patients a prompt graft allocation, independent of the local center belonging.


Assuntos
Transplante de Fígado/estatística & dados numéricos , Alocação de Recursos/métodos , Obtenção de Tecidos e Órgãos/métodos , Idoso , Feminino , Humanos , Itália , Transplante de Fígado/normas , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Obtenção de Tecidos e Órgãos/normas , Listas de Espera
7.
Eur J Histochem ; 59(1): 2455, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25820558

RESUMO

Osteonecrosis of the jaw (ONJ) is a chronic complication affecting long-term bisphosphonate-treated subjects, recognized by non-healing exposed bone in the maxillofacial region. The pathophysiological mechanism underlying ONJ has not been fully elucidated. The aim of the present study was to investigate the role of RANK/RANKL/OPG signaling pathway and, in parallel, to evaluate angiogenic and matrix mineralization processes in jaw bone necrotic samples obtained from bisphosphonate-treated subjects with established ONJ. Necrotic bone samples and native bone samples were processed for Light and Field Emission in Lens Scanning Electron Microscope (FEISEM) analyses, for Real-Time RT-PCR to evaluate the gene expression of TNFRSF11A (RANK), TNFSF11 (RANKL), and TNFSF11B (OPG) and for immunohistochemical analyses of VEGF and BSP expression. Morphological analyses performed by Light microscope and FEISEM show empty osteocytic lacunae and alteration of lamellar organization with degradation of the mineralized bone matrix in necrotic bone samples. A significant increase in TNFRSF11A, TNFSF11, TRAF6 and NFAT2 gene expression, and a reduction of TNFSF11B gene transcription level compared is also showed in necrotic bone compared to control samples. No significant difference of VEGF expression is evidenced, while lower BSP expression in necrotic bone compared to healthy samples is found. Even if the pathogenesis of bisphosphonate-associated ONJ remains unknown, a link between oral pathogens and its development seems to exist. We suppose lipopolysaccharide produced by bacteria colonizing and infecting necrotic bone and the surrounding viable area could trigger RANK/RANKL/OPG signaling pathway and, in this context, osteoclasts activation could be considered as a protective strategy carried out by the host bone tissue to delimitate the necrotic area and to counteract infection.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/fisiopatologia , Ligante RANK/fisiologia , Transdução de Sinais , Adulto , Idoso , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Ligante RANK/genética
8.
J Ethnopharmacol ; 162: 261-9, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25560668

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The decoction of the roots of Hemidesmus indicus is widely used in the Indian traditional medicine for many purposes and poly-herbal preparations containing Hemidesmus are often used by traditional medical practitioners for the treatment of cancer. In the context of anticancer pharmacology, anti-angiogenic therapy has become an effective strategy for inhibiting new vessel formation and contrast tumor growth. These considerations are supported by the evidence that most tumors originate in hypoxic conditions and limitation of oxygen diffusion stimulates the formation of tumor abnormal microvasculature. Aim of this study was to evaluate the in vitro anti-angiogenic potential of Hemidesmus indicus (0.31-0.93 mg/mL) on human umbilical vein endothelial cells and delineate the main molecular mechanisms involved in its anti-angiogenic activity both in normoxia and hypoxia. MATERIALS AND METHODS: The decoction of Hemidesmus indicus was subjected to an extensive HPLC phytochemical characterization. Its in vitro anti-angiogenic potential was investigated in normoxia and hypoxia. Cell proliferation, apoptosis induction, and inhibition of endothelial cell migration and invasion were analyzed by flow cytometry. The endothelial tube formation assay was evaluated in matrix gel. The capillary tube branch points formed were counted using a Motic AE21 microscope and a VisiCam videocamera. The regulation of key factors of the neovascularization process such as VEGF, HIF-1α and VEGFR-2 was explored at mRNA and protein level by real time PCR and flow cytometry, respectively. RESULTS: Treatment with Hemidesmus resulted in a significant inhibition of cell proliferation and tube formation in both normoxia and hypoxia. Hemidesmus differently regulated multiple molecular targets related to angiogenesis according to oxygen availability. In normoxia, the inhibition of VEGF was the main responsible for its anti-angiogenic effect; the angiogenesis inhibition induced in hypoxia was regulated by a more complex mechanism involving firstly HIF-1α inhibition, and then VEGF and VEGFR-2 down-regulation. Additionally, the inhibition of endothelial cell migration and invasion by Hemidesmus was more pronounced in normoxia than in hypoxia, possibly due to the physiological enhanced induction of invasion characteristic of hypoxia. CONCLUSIONS: Our results indicate that Hemidesmus might represent a promising therapeutic strategy for diseases in which the inhibition of angiogenesis could be beneficial, such as cancer. The antiangiogenic activity of Hemidesmus is based on multiple interactions with critical steps in the angiogenic cascade. VEGF expression stimulated by HIF-1α as well as endothelial cell migration and differentiation represent important targets of Hemidesmus action and might contribute to its cancer therapeutic efficacy that is presently emerging and offer a scientific basis for its use in traditional medicine.


Assuntos
Células Endoteliais/efeitos dos fármacos , Hemidesmus/química , Neovascularização Fisiológica/efeitos dos fármacos , Oxigênio , Extratos Vegetais/farmacologia , Células Endoteliais/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Extratos Vegetais/química
9.
Infect Immun ; 82(11): 4508-17, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25114117

RESUMO

Previous studies have indicated that group B streptococcus (GBS), a frequent human pathogen, potently induces the release of interleukin-1ß (IL-1ß), an important mediator of inflammatory responses. Since little is known about the role of this cytokine in GBS disease, we analyzed the outcome of infection in IL-1ß-deficient mice. These animals were markedly sensitive to GBS infection, with most of them dying under challenge conditions that caused no deaths in wild-type control mice. Lethality was due to the inability of the IL-1ß-deficient mice to control local GBS replication and dissemination to target organs, such as the brain and the kidneys. Moreover, in a model of inflammation induced by the intraperitoneal injection of killed GBS, a lack of IL-1ß was associated with selective impairment in the production of the neutrophil chemokines CXCL1 and CXCL2 and in neutrophil recruitment to the peritoneal cavity. Decreased blood neutrophil counts and impaired neutrophil recruitment to the brain and kidneys were also observed during GBS infection in IL-1ß-deficient mice concomitantly with a reduction in CXCL1 and CXCL2 tissue levels. Notably, the hypersusceptibility to GBS infection observed in the immune-deficient animals was recapitulated by neutrophil depletion with anti-Gr1 antibodies. Collectively, our data identify a cytokine circuit that involves IL-1ß-induced production of CXCL1 and CXCL2 and leads the recruitment of neutrophils to GBS infection sites. Moreover, our data point to an essential role of these cells in controlling the progression and outcome of GBS disease.


Assuntos
Quimiocina CXCL1/metabolismo , Quimiocina CXCL2/metabolismo , Interleucina-1beta/metabolismo , Neutrófilos/fisiologia , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/imunologia , Animais , Quimiocina CXCL1/genética , Quimiocina CXCL2/genética , Feminino , Humanos , Interleucina-1beta/genética , Camundongos , Camundongos Knockout , Peritonite/imunologia , Peritonite/microbiologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Infecções Estreptocócicas/imunologia
10.
J Wound Care ; 22(10 Suppl): S23-6, 2013 10.
Artigo em Inglês | MEDLINE | ID: mdl-24142138

RESUMO

Amniocentesis is one of the most important prenatal diagnostic procedures available to assess congenital abnormalities. It is performed worldwide due to its simplicity of execution and lack of risk. The most frequent known accidents in amniocentesis are abortion, oligohydramnios, amniositis and placental abruption, while direct fetal injuries produced by contact with the needle are rarely seen. The injuries produced are extremely variable in severity, but the most frequent is skin wounds, which usually heal as small, round depressed scars. The cases we describe concern the occurrence of iatrogenic cutaneous wound lesions to a fetus during amniocentesis. The medical-legal analysis of the cases required dermatological expertise in order to exclude a different pathogenesis for the skin injuries to the child and were assigned by the court, in order to assess the administrative compensation due to the parents of the child as a result of medical malpractice.


Assuntos
Amniocentese/efeitos adversos , Lesões Pré-Natais/etiologia , Pele/lesões , Adulto , Feminino , Humanos , Gravidez , Punções/efeitos adversos
11.
Eur J Histochem ; 57(3): e23, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-24085272

RESUMO

In this study, starting from human dental pulp cells cultured in vitro, we simulated reparative dentinogenesis using a medium supplemented with different odontogenic inductors. The differentiation of dental pulp cells in odontoblast-like cells was evaluated by means of staining, and ultramorphological, biochemical and biomolecular methods. Alizarin red staining showed mineral deposition while transmission electron microscopy revealed a synthesis of extracellular matrix fibers during the differentiation process. Biochemical assays demonstrated that the differentiated phenotype expressed odontoblast markers, such as Dentin Matrix Protein 1 (DMP1) and Dentin Sialoprotein (DSP), as well as type I collagen. Quantitative data regarding the mRNA expression of DMP1, DSP and type I collagen were obtained by Real Time PCR. Immunofluorescence data demonstrated the various localizations of DSP and DMP1 during odontoblast differentiation. Based on our results, we obtained odontoblast-like cells which simulated the reparative dentin processes in order to better investigate the mechanism of odontoblast differentiation, and dentin extracellular matrix deposition and mineralization.


Assuntos
Técnicas de Cultura de Células , Polpa Dentária/citologia , Dentina/química , Odontoblastos/citologia , Antraquinonas/química , Western Blotting , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Dentina/citologia , Eletroforese em Gel de Poliacrilamida , Proteínas da Matriz Extracelular/metabolismo , Humanos , Microscopia Eletrônica de Transmissão , Odontoblastos/metabolismo , Fosfoproteínas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Sialoglicoproteínas/metabolismo , Coloração e Rotulagem
12.
Biomed Mater ; 8(3): 035011, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23619339

RESUMO

A porous scaffold was developed to support normal tissue regeneration in the presence of residual tumor disease. It was prepared by gelatin crosslinked with dehydroascorbic acid (DHA). A physicochemical characterization of the scaffold was carried out. SEM and mercury porosimetry revealed a high porosity and interconnection of pores in the scaffold. Enzymatic degradation provided 56% weight loss in ten days. The scaffold was also evaluated in vitro for its ability to support the growth of normal cells while hindering tumor cell development. For this purpose, primary human fibroblasts and osteosarcoma tumor cells (MG-63) were seeded on the scaffold. Fibroblasts attached the scaffold and proliferated, while the tumor cells, after an initial attachment and growth, failed to proliferate and progressively underwent cell death. This was attributed to the progressive release of DHA during the scaffold degradation and its cytotoxic activity towards tumor cells.


Assuntos
Antineoplásicos/química , Ácido Desidroascórbico/química , Gelatina/química , Alicerces Teciduais/química , Antineoplásicos/administração & dosagem , Materiais Biocompatíveis/química , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Reagentes de Ligações Cruzadas , Ácido Desidroascórbico/administração & dosagem , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/patologia , Neoplasia Residual/cirurgia , Regeneração , Engenharia Tecidual
13.
Eur J Histochem ; 57(4): e32, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24441185

RESUMO

Dentin matrix protein 1 (DMP1) and dentin sialophosphoprotein (DSPP) are extracellular matrix proteins produced by odontoblasts involved in the dentin mineralization. The aim this study was to compare the distribution of DMP1 and DSPP in human sound dentin vs human sclerotic dentin. Sixteen sound and sixteen carious human molars were selected, fixed in paraformaldehyde and processed for immunohistochemical detection of DMP1 and DSPP by means of light microscopy, transmission electron microscopy (TEM) and high-resolution field emission in-lens scanning electron microscopy (FEI-SEM). Specimens were submitted to a pre-embedding or a post-embedding immunolabeling technique using primary antibodies anti DMP1 and anti-DSPP and gold-conjugated secondary antibodies. Other samples were processed for the detection of DMP1 and DSPP levels. Dentin from these samples was mechanically fractured to powder, then a protein extraction and a protein level detection assay were performed. DMP1 and DSPP were more abundant in carious than in sound samples. Immunohistochemical analyses in sclerotic dentin disclosed a high expression of DMP1 and DSPP inside the tubules, suggesting an active biomineralization of dentin by odontoblasts. Furthermore, the detection of small amounts of these proteins inside the tubules far from the carious lesion, as shown in the present study, is consistent with the hypothesis of a preventive defense of all dentin after a noxious stimulus has undermined the tooth.


Assuntos
Cárie Dentária/metabolismo , Proteínas da Matriz Extracelular/biossíntese , Fosfoproteínas/biossíntese , Sialoglicoproteínas/biossíntese , Colorimetria , Cárie Dentária/patologia , Humanos , Imuno-Histoquímica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Odontoblastos
14.
Eur Rev Med Pharmacol Sci ; 16(11): 1506-12, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23111962

RESUMO

BACKGROUND: Infections caused by extracellular Gram positive bacteria are still a major health problems. Better understanding of the mechanisms underlying immune responses to these organisms is key to develop pharmacological agents, including vaccines, to control these infections. OBJECTIVE AND PERSPECTIVES: The objective of this review is to highlight the importance of nucleic acid-sensing, intracellular Toll-like receptors in innate immune recognition and in host defenses against extracellular bacteria. CONCLUSIONS: Toll-like receptors 7 and 9 have a major role in inducing host-protective type I interferon responses in conventional dendritic cells in response to streptococci and other extracellular gram positive bacteria. Moreover an as yet unidentified MyD88-dependent receptor is likely responsible for proinflammatory cytokine induction in response to these pathogens.


Assuntos
Bactérias Gram-Positivas/imunologia , Receptores Toll-Like/imunologia , Animais , Endossomos/imunologia , Transdução de Sinais
15.
Int J Gynecol Cancer ; 18(4): 615-20, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18754135

RESUMO

The aim of this paper was to assess hypersensitivity reactions in 69 patients who received carboplatin (CBDCA) retreatment for recurrent ovarian cancer. Hypersensitivity reactions developed in 15 (21.7%) patients and occurred during the second cycle of retreatment in 13 (86.7%) of them. Reactions consisted of skin rash, flushing, itching, or abdominal cramping in eight (53.3%) and severe respiratory or cardiovascular events in seven patients (46.7%). One patient had a chest pain, without any other symptoms suggestive of hypersensitivity, followed by cardiac arrest unresponsive to standard resuscitative measures. All the other cases promptly recovered from symptoms. Logistic regression analysis showed that allergy history and CBDCA retreatment interval (interval time between the last cycle of first-line chemotherapy and CBDCA retreatment) were independent predictive variables for the risk of hypersensitivity, whereas patient age, first-line chemotherapy, total CBDCA dose given during first-line treatment, recurrence treated with CBDCA (first versus other), and CBDCA regimen at recurrence had no predictive value. Hypersensitivity reaction rate was higher in patients with CBDCA retreatment interval longer than 23.4 months compared to those with a shorter interval (36.3% versus 8.3%, P = 0.0132). Nine patients were subsequently treated with cisplatin, and two (22.2%) still developed allergic reactions. In conclusion, hypersensitivity reactions to CBDCA retreatment can occur in approximately one fifth of the cases, and a CBDCA retreatment interval longer than 2 years appears to be the strongest predictive variable for the development of allergic reactions.


Assuntos
Carboplatina/efeitos adversos , Carboplatina/uso terapêutico , Carcinoma/tratamento farmacológico , Hipersensibilidade a Drogas/epidemiologia , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carcinoma/cirurgia , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/complicações , Neoplasias Ovarianas/cirurgia , Estudos Retrospectivos , Terapia de Salvação , Fatores de Tempo
16.
Cell Biol Toxicol ; 23(5): 313-22, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17486417

RESUMO

The cytotoxicity of dental composites has been attributed to the release of residual monomers from polymerized adhesive systems due to degradation processes or the incomplete polymerization of materials. 2-Hydroxyethyl methacrylate (HEMA) is one of the major components released from dental adhesives. Cytotoxic effects due to high concentrations of HEMA have already been investigated, but the influence of minor toxic concentrations on specific proteins such as type I collagen has not been studied in depth. The objective of this project was to study the effect of minor toxic concentrations of HEMA on human gingival fibroblasts (HGFs), investigating modification in cell morphology, cell viability, and the influence on type I collagen protein. Primary lines of human gingival fibroblasts were exposed to 3 mmol/L HEMA for different periods of time (24 h, 72 h, 96 h). The cell vitality was determined by MTT assay, and high-resolution scanning electron microscopy analysis was performed to evaluate differences in cell morphology before and after treatment. The presence and localization of type I collagen was determined by immunofluorescence in HGFs treated with HEMA for the same period of time. The vitality of the cells decreased after 72 h of exposure. The HGFs grown in monolayer and observed by field emission in-lens scanning electron microscopy demonstrated a preserved surface morphology after 24 h of treatment, while they showed an altered morphology after 96 h of treatment. Immunofluorescence demonstrated a reduction of type I collagen due to HEMA exposure after 96 h. From these results, we conclude that low concentrations of HEMA can significantly alter the morphology of human gingival fibroblasts and interfere with the presence of type I collagen protein.


Assuntos
Colágeno Tipo I/metabolismo , Resinas Compostas/toxicidade , Fibroblastos/citologia , Gengiva/citologia , Metacrilatos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cimentos Dentários/toxicidade , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Gengiva/efeitos dos fármacos , Gengiva/metabolismo , Humanos
17.
Micron ; 37(2): 146-53, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16361104

RESUMO

The purpose of this study was to analyze the inner structure of chromosomes in cells arrested, fixed and cryosectioned in metaphase. The chromosomes in metaphase maps prepared using standard cytogenetic protocols, are usually covered by cellular debris, which obscures the structural details on the surface and limits analysis by techniques when using nanometric resolution. By using cryosectioning, the debris is removed and it is possible to analyze the internal structure of the chromosomes. We described the ultrastructure of chromosome sections fixed with either acetic acid, methanol or glutaraldehyde, evaluating the effect and the influence of the fixative on the morphology. Furthermore, we subjected those cells previously fixed with glutaraldehyde to osmic maceration in order to better visualize the intracellular structure. All samples were examined with a Field Emission In Lens Scanning Electron Microscope (FEISEM), which allows high-resolution analysis of biological samples without any metal coating. The results showed a package morphology in samples fixed with glutaraldehyde, mainly due to the high capacity of the fixative to strongly crosslink the proteins. In contrast, the fibrillar structure seen in cryosections fixed with acetic acid/methanol is due to the propensity of the fixatives to extract and remove proteins. We propose that in situ chromosomes fixed with glutaraldehyde and then osmicated are a good model for studying the inner structure of chromosomes by using high resolution scanning electron microscopy.


Assuntos
Cromossomos Humanos/ultraestrutura , Microscopia Eletrônica de Varredura/métodos , Fixação de Tecidos/métodos , Crioultramicrotomia , Células HeLa , Humanos , Metáfase
18.
J Biomed Mater Res A ; 67(1): 11-7, 2003 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-14517856

RESUMO

Immunocytochemical analysis is a fundamental and selective technique for identifying different molecular components of human dental structure. The hypothesis tested here is that the application of different etching solutions on dentin does not hinder collagen fibrils and proteoglycans from maintaining their immunochemical antigenicity. Human dentin disks were treated with 0.5M of EDTA, citric acid, maleic acid, or phosphoric acid (for 15 or 30 s). A double-immunolabeling technique was performed to identify, simultaneously, collagen fibrils and chondroitin sulfate. The use of different acids resulted in different degrees of labeling. Maleic and citric acids revealed a diffuse and intense labeling for both collagen fibrils and proteoglycans. The use of phosphoric acid on dentin showed a massive coagulation of the proteoglycans (15 s) or very low labeling (30 s). These data clarify that the use of acids on dentin components is able to modify their antigenicity. Moreover, the double-labeling immunocytochemical technique allows understanding of the spatial relationships between the collagen fibrils and proteoglycans of the dentin matrix.


Assuntos
Dentina/imunologia , Imuno-Histoquímica/métodos , Animais , Anticorpos/imunologia , Colágeno/imunologia , Dentina/ultraestrutura , Ácido Edético , Ouro , Humanos , Microscopia Eletrônica de Varredura , Proteoglicanas/imunologia
19.
Diabetes Res Clin Pract ; 62(2): 131-7, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14581150

RESUMO

In order to evaluate the prevalence of gestational diabetes mellitus (GDM) and the presence of risk factors for GDM, we conducted a retrospective study of a cohort of Italian women. In addition, we compared universal versus selective screening to validate the ADA's recommendations in our population. From June 1st, 1995 to December 31st, 2001, universal screening for GDM was performed in 3950 women. The glucose challenge test (GCT) was positive (GCT+) in 1389 cases (35.2%). The 1-h glucose level after GCT enabled us to diagnose GDM directly in 24 pregnant women. Oral glucose tolerance test (OGTT) was performed in 1221 GCT+ women (144 cases with GCT+ dropped out) and GDM was diagnosed in 284 (23.2%) of them. OGTT was also performed in 391 randomly chosen, women from the GCT negative (GCT-) group. In this last group 25 (6.3%) women had GDM. Thus, the total number of subjects with GDM was 333 out of 3806 with a prevalence of 8.74% in the entire cohort. Assuming that the rate of GDM observed in the random sample of GCT- women is applicable to the whole group of 2561 GCT- women, then 161 GCT- patients could also have GDM. This will further increase the estimated prevalence for the whole cohort up to 12.3% (i.e. 469 out of 3806 pregnant women). There were 236 (5.6%) women with a low risk for GDM (normal weight, age less than 25 years and without a family history of diabetes). In this group we found 34 cases and five cases with positive screening test and GDM, respectively. Thus, if we excluded low risk women from the screening test, as suggested by ADA recommendations, only five women with GDM would have been missed. However, about 95% of our population were at medium or high risk for GDM and, therefore, would have been screened. The rate of GDM was significantly higher in women with a positive history of diabetes, increasing age, previous pregnancies, pre-pregnancy overweight and short stature. After logistic regression analysis, GDM diagnosis was significantly correlated with age (P<0.0001), pre-pregnancy BMI (P<0.0001), weight gain (P<0.0001) and family history of diabetes (P<0.01).


Assuntos
Diabetes Gestacional/epidemiologia , Adulto , Estatura , Peso Corporal , Diabetes Gestacional/sangue , Feminino , Teste de Tolerância a Glucose , Humanos , Itália/epidemiologia , Programas de Rastreamento/métodos , Paridade , Gravidez , Prevalência , Fatores de Risco , Sociedades Médicas
20.
Acta Diabetol ; 39(2): 69-73, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12120916

RESUMO

This study retrospectively evaluated two groups of pregnant women. Group A women (n=1,338) were universally screened for gestational diabetes mellitus (GDM) and GDM patients were intensively treated. In Group B (n=4,035), screening was performed only in women at high risk for GDM and treatment was conventional. This study confirms the validity of a cost-effective screening program for the diagnosis of GDM and that selective screening may be an option only in a situation where healthcare resources are very scarce and/or universal screening of any kind is not feasible. Once the diagnosis of GDM has been made, metabolic management with an intensive approach is important to reduce maternal and fetal morbidity. Diagnosis of GDM and intensive treatment represent a cost for the public health system, but permit a significant monetary savings in terms of costs linked to maternal and neonatal morbidity.


Assuntos
Diabetes Gestacional/diagnóstico , Diabetes Gestacional/tratamento farmacológico , Custos de Cuidados de Saúde , Programas de Rastreamento/economia , Adulto , Análise Custo-Benefício , Diabetes Gestacional/metabolismo , Feminino , Humanos , Itália , Gravidez , Estudos Retrospectivos
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