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1.
EMBO J ; 41(5): e109386, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35112724

RESUMEN

The mechanisms whereby neutrophils respond differentially to live and dead organisms are unknown. We show here that neutrophils produce 5- to 30-fold higher levels of the Cxcl2 chemokine in response to live bacteria, compared with killed bacteria or isolated bacterial components, despite producing similar levels of Cxcl1 or pro-inflammatory cytokines. Secretion of high levels of Cxcl2, which potently activates neutrophils by an autocrine mechanism, requires three signals. The first two signals are provided by two different sets of signal peptides released by live bacteria, which selectively activate formylated peptide receptor 1 (Fpr1) and Fpr2, respectively. Signal 3 originates from Toll-like receptor activation by microbial components present in both live and killed bacteria. Mechanistically, these signaling pathways converge at the level of the p38 MAP kinase, leading to activation of the AP-1 transcription factor and to Cxcl2 induction. Collectively, our data demonstrate that the simultaneous presence of agonists for Fpr1, Fpr2, and Toll-like receptors represents a unique signature associated with viable bacteria, which is sensed by neutrophils and induces Cxcl2-dependent autocrine cell activation.


Asunto(s)
Bacterias/metabolismo , Neutrófilos/metabolismo , Proteínas Proto-Oncogénicas c-fes/metabolismo , Receptores Toll-Like/metabolismo , Animales , Citocinas/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/fisiología
2.
Environ Res ; 247: 118275, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38246295

RESUMEN

The study investigated the dissipation ability of a vegetated free water surface (FWS) constructed wetland (CW) in treating pesticides-contaminated agricultural runoff/drainage water in a rural area belonging to Bologna province (Italy). The experiment simulated a 0.1% pesticide agricultural water runoff/drainage event from a 12.5-ha farm by dissolving acetamiprid, metalaxyl, S-metolachlor, and terbuthylazine in 1000 L of water and pumping it into the CW. Water and sediment samples from the CW were collected for 4 months at different time intervals to determine pesticide concentrations by multiresidue extraction and chromatography-mass spectrometry analyses. In parallel, no active compounds were detected in the CW sediments during the experimental period. Pesticides dissipation in the wetland water compartment was modeled according to best data practices by fitting the data to Single First Order (SFO), First Order Multi-Compartment (FOMC) and Double First Order in Parallel (DFOP) kinetic models. SFO (except for metalaxyl), FOMC and DFOP kinetic models adequately predicted the dissipation for the four investigated molecules, with the DFOP kinetic model that better fitted the observed data. The modeled distribution of each pesticide between biomass and water in the CW highly correlated with environmental indexes as Kow and bioconcentration factor. Computed DT50 by DFOP model were 2.169, 8.019, 1.551 and 2.047 days for acetamiprid, metalaxyl, S-metolachlor, and terbuthylazine, respectively. Although the exact degradation mechanisms of each pesticide require further study, the FWS CW was found to be effective in treating pesticides-contaminated agricultural runoff/drainage water within an acceptable time. Therefore, this technology proved to be a valuable tool for mitigating pesticides runoff occurring after intense rain events.


Asunto(s)
Acetamidas , Alanina/análogos & derivados , Neonicotinoides , Plaguicidas , Triazinas , Contaminantes Químicos del Agua , Humedales , Plaguicidas/análisis , Agricultura/métodos , Agua , Contaminantes Químicos del Agua/análisis
3.
J Environ Manage ; 359: 121109, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38723500

RESUMEN

The impact of climate change on water availability and quality has affected agricultural irrigation. The use of treated wastewater can alleviate water in agriculture. Nevertheless, it is imperative to ensure proper treatment of wastewater before reuse, in compliance with current regulations of this practice. In decentralized agricultural scenarios, the lack of adequate treatment facilities poses a challenge in providing treated wastewater for irrigation. Hence, there is a critical need to develop and implement innovative, feasible, and sustainable treatment solutions to secure the use of this alternative water source. This study proposes the integration of intensive treatment solutions and natural treatment systems, specifically, the combination of up-flow anaerobic sludge blanket reactor (UASB), anaerobic membrane bioreactor (AnMBR), constructed wetlands (CWs), and ultraviolet (UV) disinfection. For this purpose, a novel demo-scale plant was designed, constructed and implemented to test wastewater treatment and evaluate the capability of the proposed system to provide an effluent with a quality in compliance with the current European wastewater reuse regulatory framework. In addition, carbon-sequestration and energy analyses were conducted to assess the sustainability of the proposed treatment approach. This research confirmed that UASB rector can be employed for biogas production (2.5 L h-1) and energy recovery from organic matter degradation, but its effluent requires further treatment steps to be reused in agricultural irrigation. The AnMBR effluent complied with class A standards for E. coli, boasting a concentration of 0 CFU 100 mL-1, and nearly negligible TSS levels. However, further reduction of BOD5 (35 mg L-1) is required to reach water quality class A. CWs efficiently produced effluent with BOD5 below 10 mg L-1 and TSS close to 0 mg L-1, making it suitable for water reuse and meeting class A standards. Furthermore, CWs demonstrated significantly higher energy efficiency compared to intensive treatment systems. Nonetheless, the inclusion of a UV disinfection unit after CWs was required to attain water class B standards.


Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas Residuales , Humedales , Anaerobiosis , Eliminación de Residuos Líquidos/métodos , Agricultura , Carbono
4.
J Environ Manage ; 348: 119278, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37832301

RESUMEN

Climate change poses challenges to agricultural water resources, both in terms of quantity and quality. As an adaptation measure, the new European Regulation (EU) 2020/741 establishes different water quality classes for the use of reclaimed water in agricultural irrigation. Italy is also working on the definition of a new regulation on reclaimed water reuse for agricultural irrigation (in substitution of the current one) that will also include the specific requirements imposed by the European one. Nature-based Solutions (NBS) can be a cost-effective and environmentally friendly way to facilitate water reclamation and reuse. The present study reports the outcomes of a long-term monitoring campaign of two NBS (e.g., a constructed wetland (CW) and a lagoon system (LS)) comparing influent and effluent concentrations of different contaminants (e.g., E. coli, BOD5, TSS, TN and TP) with the threshold values imposed by the new regulations. The results showed that in both the case studies, E. coli (about 100 CFU 100 mL-1) and BOD5 (lower than 25 mg L-1) mean effluent concentration need to be further reduced in reclaimed water to be suitable for unlimited reuse. As a negative aspect, in both the monitored NBS, an increase in TSS mean concentration in the effluent was observed, up to 40 mg L-1 in the case of the LS, making reclaimed water unsuitable for agricultural reuse. The CW has proven to be more effective in nitrogen removal (the effluent mean concentration was 3.4 mg L-1), whereas the LS was better at phosphorus removal (with an effluent mean concentration of 0.4 mg L-1). Based on the results, recommendations were made to further improve the performance of both systems in order to have adequate water quality, even for class A. Furthermore, the capacity of reclaimed water to meet crop water and nutrient needs was analyzed, and total nitrogen removal rate coefficients were calculated for the design of future LSs.


Asunto(s)
Riego Agrícola , Purificación del Agua , Riego Agrícola/métodos , Humedales , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , Escherichia coli
5.
J Immunol ; 204(3): 660-670, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31852751

RESUMEN

The influx of neutrophils to infection sites is a fundamental step in host defenses against the frequent human pathogen group B Streptococcus (GBS) and other extracellular bacteria. Using a mouse model of GBS-induced peritonitis, we show in this study that the chemokines Cxcl1 and Cxcl2 play distinctive roles in enhancing the recruitment and the antibacterial activities of neutrophils in a manner that is linked to differences in the cellular sources of these mediators. Cell depletion experiments demonstrated that neutrophils make a significant contribution to the in vivo production of Cxcl2 but not Cxcl1. In vitro, neutrophils responded weakly to LPS but released high levels of Cxcl2 after stimulation with GBS or other bacteria. Neutrophil-derived Cxcl2 acted in an autocrinous manner to increase its own production and to enhance antibacterial activities, including the release of oxygen radicals. In both neutrophils and macrophages, the production of Cxcl1/2 largely required the presence of functional UNC93B1, a chaperone protein involved in signaling by endosomal TLRs. Moreover, the phenotype of UNC93B1-defective phagocytes could be recapitulated by the simultaneous absence of TLR7, 9, and 13 but not by the absence of individual TLRs. Collectively, our data show that neutrophils recognize Gram-positive and Gram-negative bacteria by means of multiple phagosomal TLRs, resulting in de novo synthesis of Cxcl2, amplification of neutrophil recruitment, and potentiation of their antibacterial activities. These data may be useful to devise alternative therapeutic strategies aimed at enhancing the recruitment and the functional activities of polymorphonuclear leukocytes during infections caused by antibiotic-resistant bacteria.


Asunto(s)
Infecciones Bacterianas/inmunología , Quimiocina CXCL2/metabolismo , Endosomas/metabolismo , Neutrófilos/inmunología , Peritonitis/inmunología , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunidad Innata , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Infiltración Neutrófila , Receptores Toll-Like/metabolismo
6.
Nat Immunol ; 10(6): 587-94, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19430477

RESUMEN

Little is known of how and where bacterial recognition triggers the induction of type I interferon. Whether the type of recognition receptor used in these responses is determined by the subcellular location of bacteria is not understood. Here we show that phagosomal bacteria such as group B streptococcus, but not cytosolic bacteria, potently induced interferon in conventional dendritic cells by a mechanism that required Toll-like receptor 7, the adaptor MyD88 and the transcription factor IRF1, all of which localized together with bacterial products in degradative vacuoles bearing lysosomal markers. Thus, this cell type-specific recognition pathway links lysosomal recognition of bacterial RNA with a robust, host-protective interferon response.


Asunto(s)
Células Dendríticas/metabolismo , Lisosomas/metabolismo , Glicoproteínas de Membrana/metabolismo , Streptococcus agalactiae/inmunología , Receptor Toll-Like 7/metabolismo , Animales , Animales Recién Nacidos/inmunología , Animales Recién Nacidos/microbiología , Células Dendríticas/inmunología , Femenino , Factor 1 Regulador del Interferón/inmunología , Factor 1 Regulador del Interferón/metabolismo , Interferón beta/biosíntesis , Lisosomas/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Glicoproteínas de Membrana/inmunología , Ratones , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/inmunología , Factor 88 de Diferenciación Mieloide/metabolismo , Fagocitosis , Fagosomas/inmunología , Fagosomas/metabolismo , ARN Bacteriano/metabolismo , Transducción de Señal , Infecciones Estreptocócicas/inmunología , Receptor Toll-Like 7/inmunología
7.
J Card Surg ; 36(7): 2539-2540, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33738815

RESUMEN

An 82-year-old woman with precordial pain at rest was admitted to the Emergency Department for possible cardiac heart disease; electrocardiogram excluded ischemia and high-sensitive troponin was normal. Echocardiogram revealed a hyperechoic mass adjacent to the mitral annulus. Electrocardiography-gated computed tomography (CT) angiography exam confirmed the presence of the mass protruding into the atrioventricular groove, adjacent to the posterior mitral. On the precontrast images the lesion was hyperdense with some scattered central calcific spots. CT findings are typical of a giant caseous calcification of the mitral annulus and excluded the diagnoses of pseudoaneurysm (it does not show any communication with the left ventricular cavity), neoplasm/abscess (complete caseous/calcified content) or infected/abscessified mitral calcification (absence of internal hypodense core). This is a benign condition that can be easily misdiagnosed as ventricular aneurysm or pseudoaneurysm on the contrast-enhanced images, when the caseous content is isodense to the iodinated blood pool.


Asunto(s)
Aneurisma Falso , Calcinosis , Enfermedades de las Válvulas Cardíacas , Anciano de 80 o más Años , Aneurisma Falso/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Ecocardiografía , Femenino , Humanos , Válvula Mitral/diagnóstico por imagen
8.
New Microbiol ; 44(4): 227-233, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34942012

RESUMEN

The aim of this study was to determine the prevalence of extended-spectrum ß-lactamases (ESBLs)- and carbapenemase-producing fermentative Gram-negative bacteria (FGNB) in a University Hospital in Southern Italy. These bacteria have the potential to disseminate bacterial resistance in healthcare settings and cause untreatable and prolonged infections associated with high rates of mortality. A retrospective observational study was carried out in a University Hospital in Sicily from January to December 2019. A total of 1046 FGNB were recovered from different clinical samples among which 40%, 15% and 37% were, respectively, MDR, carbapenemase and ESBL producers. Antibiotic resistance profile of FGNB against the first-line drugs was remarkably high. K. pneumoniae (57%) followed by E. coli (27%) were found here as the major sources of ESBL producers. The highest proportion of ESBL producers was from ICU ward (72%), and were isolated from urine samples (63.6%) followed by blood samples (54%). Carbapenemase production among the FGNB in our study was about 0.9%, which is more than twice than the prevalence rate reported by the European Antimicrobial Resistance Surveillance Network (ECDC) (0.4%). To our knowledge, this is the first report on the prevalence of ESBL and carbapenemase-producing FGNB in this region. Our data clearly indicate the importance of implementing antibiotic stewardship strategies in our region to reduce the unnecessary use of antibiotics.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Escherichia coli , Antibacterianos/farmacología , Proteínas Bacterianas , Bacterias Gramnegativas , Hospitales , Humanos , Pruebas de Sensibilidad Microbiana , Sicilia , beta-Lactamasas
9.
Med Mycol ; 58(8): 1138-1148, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-32246714

RESUMEN

Members of the C. neoformans/C. gattiii species complex are an important cause of serious humans infections, including meningoencephalitis. We describe here a 45 kDa extracellular cellulase purified from culture supernatants of C. neoformans var. neoformans. The N-terminal sequence obtained from the purified protein was used to isolate a clone containing the full-length coding sequence from a C. neoformans var. neoformans (strain B-3501A) cDNA library. Bioinformatics analysis indicated that this gene is present, with variable homology, in all sequenced genomes of the C. neoformans/C. gattii species complex. The cDNA clone was used to produce a recombinant 45 kDa protein in E. coli that displayed the ability to convert carboxymethyl cellulose and was therefore designated as NG-Case (standing for Neoformans Gattii Cellulase). To explore its potential use as a vaccine candidate, the recombinant protein was used to immunize mice and was found capable of inducing T helper type 1 responses and delayed-type hypersensitivity reactions, but not immune protection against a highly virulent C. neoformans var grubii strain. These data may be useful to better understand the mechanisms underlying the ability C. neoformans/C. gattii to colonize plant habitats and to interact with the human host during infection.


Asunto(s)
Celulasa/inmunología , Cryptococcus/enzimología , Proteínas Fúngicas/inmunología , Animales , Carboximetilcelulosa de Sodio/metabolismo , Celulasa/química , Celulasa/genética , Celulasa/metabolismo , Criptococosis/inmunología , Criptococosis/microbiología , Cryptococcus/genética , Cryptococcus/inmunología , Cryptococcus/metabolismo , Cryptococcus neoformans/enzimología , Cryptococcus neoformans/genética , Cryptococcus neoformans/inmunología , Cryptococcus neoformans/metabolismo , Medios de Cultivo Condicionados , Citocinas/inmunología , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Inmunización , Ratones , Peso Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Células TH1/inmunología
10.
Int J Mol Sci ; 21(24)2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33317145

RESUMEN

Neuroinflammation and autoimmune mechanisms have a key part in the pathogenesis of Parkinson's disease (PD). Therefore, we evaluated the role of Toll-like receptors (TLRs) as a link between inflammation and autoimmunity in PD. An in vivo model of PD was performed by administration of 1-metil 4-fenil 1,2,3,6-tetraidro-piridina (MPTP) at the dose of 20 mg/kg every 2 h for a total administration of 80/kg, both in single Knock Out (KO) mice for TLR7, TLR 8, and TLR9 and in double KO mice for TLR 7/8-/-. All animals were compared with WT animals used as a control group. All animals were sacrificed after 7 days form the first administration of MPTP. The genetic absence of TLR 7 and 8 modified the PD pathway, increasing the immunoreactivity for TH and DAT compared to PD groups and decreasing microglia and astrocytes activation. Moreover, the deletion of TLR7 and TLR8 significantly reduced T-cell infiltration in the substantia nigra and lymph nodes, suggesting a reduction of T-cell activation. Therefore, our result highlights a possibility that an immunotherapy approach, by using a dual antagonist of TLR 7 and 8, could be considered as a possible target to develop new therapies for Parkinson diseases.


Asunto(s)
Intoxicación por MPTP/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 8/metabolismo , Animales , Astrocitos/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Ratones , Ratones Endogámicos C57BL , Microglía/metabolismo , Sustancia Negra/metabolismo , Linfocitos T/metabolismo , Receptor Toll-Like 7/genética , Receptor Toll-Like 8/genética
11.
Mol Microbiol ; 110(1): 82-94, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30030946

RESUMEN

Binding of microbial pathogens to host vitronectin (Vtn) is a common theme in the pathogenesis of invasive infections. In this study, we characterized the role of Vtn in the invasion of mucosal epithelial cells by Streptococcus agalactiae (i.e. group B streptococcus or GBS), a frequent human pathogen. Moreover, we identified PbsP, a previously described plasminogen-binding protein of GBS, as a dual adhesin that can also interact with human Vtn through its streptococcal surface repeat (SSURE) domains. Deletion of the pbsP gene decreases both bacterial adhesion to Vtn-coated inert surfaces and the ability of GBS to interact with epithelial cells. Bacterial adherence to and invasion of epithelial cells were either inhibited or enhanced by cell pretreatment with, respectively, anti-Vtn antibodies or Vtn, confirming the role of Vtn as a GBS ligand on host cells. Finally, antibodies directed against the integrin αv subunit inhibited Vtn-dependent cell invasion by GBS. Collectively, these results indicate that Vtn acts as a bridge between the SSURE domains of PbsP on the GBS surface and host integrins to promote bacterial invasion of epithelial cells. Therefore, inhibition of interactions between PbsP and extracellular matrix components could represent a viable strategy to prevent colonization and invasive disease by GBS.


Asunto(s)
Proteínas Bacterianas/metabolismo , Integrina alfaV/metabolismo , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/metabolismo , Streptococcus agalactiae/patogenicidad , Vitronectina/metabolismo , Células A549 , Adhesión Bacteriana/genética , Proteínas Bacterianas/genética , Células CACO-2 , Pared Celular/metabolismo , Células Epiteliales/microbiología , Humanos , Integrina alfaV/genética , Dominios Proteicos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Streptococcus agalactiae/genética , Vitronectina/genética
12.
PLoS Genet ; 11(4): e1005149, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25875445

RESUMEN

Mutations in SPAST, encoding spastin, are the most common cause of autosomal dominant hereditary spastic paraplegia (HSP). HSP is characterized by weakness and spasticity of the lower limbs, owing to progressive retrograde degeneration of the long corticospinal axons. Spastin is a conserved microtubule (MT)-severing protein, involved in processes requiring rearrangement of the cytoskeleton in concert to membrane remodeling, such as neurite branching, axonal growth, midbody abscission, and endosome tubulation. Two isoforms of spastin are synthesized from alternative initiation codons (M1 and M87). We now show that spastin-M1 can sort from the endoplasmic reticulum (ER) to pre- and mature lipid droplets (LDs). A hydrophobic motif comprised of amino acids 57 through 86 of spastin was sufficient to direct a reporter protein to LDs, while mutation of arginine 65 to glycine abolished LD targeting. Increased levels of spastin-M1 expression reduced the number but increased the size of LDs. Expression of a mutant unable to bind and sever MTs caused clustering of LDs. Consistent with these findings, ubiquitous overexpression of Dspastin in Drosophila led to bigger and less numerous LDs in the fat bodies and increased triacylglycerol levels. In contrast, Dspastin overexpression increased LD number when expressed specifically in skeletal muscles or nerves. Downregulation of Dspastin and expression of a dominant-negative variant decreased LD number in Drosophila nerves, skeletal muscle and fat bodies, and reduced triacylglycerol levels in the larvae. Moreover, we found reduced amount of fat stores in intestinal cells of worms in which the spas-1 homologue was either depleted by RNA interference or deleted. Taken together, our data uncovers an evolutionarily conserved role of spastin as a positive regulator of LD metabolism and open up the possibility that dysfunction of LDs in axons may contribute to the pathogenesis of HSP.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Proteínas de Drosophila/metabolismo , Gotas Lipídicas/metabolismo , Metabolismo de los Lípidos , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/genética , Secuencias de Aminoácidos , Animales , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Retículo Endoplásmico/metabolismo , Mucosa Intestinal/metabolismo , Músculo Esquelético/metabolismo , Neuronas/metabolismo , Transporte de Proteínas , Triglicéridos/metabolismo
13.
Mol Microbiol ; 101(1): 27-41, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26888569

RESUMEN

Streptococcus agalactiae (Group B Streptococcus or GBS) is a leading cause of invasive infections in neonates whose virulence is dependent on its ability to interact with cells and host components. We here characterized a surface protein with a critical function in GBS pathophysiology. This adhesin, designated PbsP, possesses two Streptococcal Surface Repeat domains, a methionine and lysine-rich region, and a LPXTG cell wall-anchoring motif. PbsP mediates plasminogen (Plg) binding both in vitro and in vivo and we showed that cell surface-bound Plg can be activated into plasmin by tissue plasminogen activator to increase the bacterial extracellular proteolytic activity. Absence of PbsP results in a decreased bacterial transmigration across brain endothelial cells and impaired virulence in a murine model of infection. PbsP is conserved among the main GBS lineages and is a major plasminogen adhesin in non-CC17 GBS strains. Importantly, immunization of mice with recombinant PbsP confers protective immunity. Our results indicate that GBS have evolved different strategies to recruit Plg which indicates that the ability to acquire cell surface proteolytic activity is essential for the invasiveness of this bacterium.


Asunto(s)
Adhesinas Bacterianas/metabolismo , Plasminógeno/metabolismo , Streptococcus agalactiae/metabolismo , Secuencia de Aminoácidos , Animales , Adhesión Bacteriana/fisiología , Pared Celular/metabolismo , Células Endoteliales/metabolismo , Fibrinolisina/metabolismo , Humanos , Ratones , Unión Proteica , Infecciones Estreptocócicas/microbiología , Streptococcus/metabolismo , Streptococcus agalactiae/genética , Streptococcus agalactiae/patogenicidad , Virulencia
14.
J Gen Virol ; 98(6): 1372-1376, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28613147

RESUMEN

Merkel cell polyomavirus (MCPyV) has been identified in samples of Merkel cell carcinoma (MCC), an aggressive skin cancer. Seroepidemiologic studies indicated a high frequency of MCPyV infection in humans, suggesting respiratory and faecal-oral routes, or transmission by skin contact. Since MCC is more frequent in immunocompromised patients, a reactivation of MCPyV latently infecting target cells has been proposed. However, neither definite ways of transmission nor specific target organs have been identified with certainty. Ten autopsies with an extensive organ sampling for a total of 121 specimens (tissue and blood samples) were collected. All tissue specimens were fixed in formalin and embedded in paraffin. Real-time PCR was performed to quantify the copy number of the large T antigen (LT) gene and the capsid VP1 gene of MCPyV. MCPyV LT and/or VP genes were detected in all of the collected specimens. A high prevalence of MCPyV was found in the blood (six cases) and lung (five cases); the brain was positive in three cases. The highest viral copy number was detected in blood from two autopsies (21 610 570.09 copies per 105 cells and 380 413.25 copies per 105 cells), whereas the viral copy number in the other organs was low. Our data confirm the high frequency of MCPyV infection in the general population, which seems to indicate that the respiratory tract is a possible route for viral transmission and viral persistence in the brain. The frequent detection of MCPyV DNA in blood suggests that circulating leukocytes could be one of the reservoirs of MCPyV, whereas the high viral copy number also seems to indicate the possibility of viral reactivation in immunocompetent adults.


Asunto(s)
Autopsia , ADN Viral/aislamiento & purificación , Poliomavirus de Células de Merkel/aislamiento & purificación , Infecciones por Polyomavirus/virología , Infecciones Tumorales por Virus/virología , Humanos , Poliomavirus de Células de Merkel/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Carga Viral
15.
Am J Phys Anthropol ; 163(3): 446-461, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28345756

RESUMEN

OBJECTIVES: Early evidence for the treatment of dental pathology is found primarily among food-producing societies associated with high levels of oral pathology. However, some Late Pleistocene hunter-gatherers show extensive oral pathology, suggesting that experimentation with therapeutic dental interventions may have greater antiquity. Here, we report the second earliest probable evidence for dentistry in a Late Upper Paleolithic hunter-gatherer recovered from Riparo Fredian (Tuscany, Italy). MATERIALS AND METHODS: The Fredian 5 human consists of an associated maxillary anterior dentition with antemortem exposure of both upper first incisor (I1 ) pulp chambers. The pulp chambers present probable antemortem modifications that warrant in-depth analyses and direct dating. Scanning electron microscopy, microCT and residue analyses were used to investigate the purported modifications of external and internal surfaces of each I1 . RESULTS: The direct date places Fredian 5 between 13,000 and 12,740 calendar years ago. Both pulp chambers were circumferentially enlarged prior to the death of this individual. Occlusal dentine flaking on the margin of the cavities and striations on their internal aspects suggest anthropic manipulation. Residue analyses revealed a conglomerate of bitumen, vegetal fibers, and probable hairs adherent to the internal walls of the cavities. DISCUSSION: The results are consistent with tool-assisted manipulation to remove necrotic or infected pulp in vivo and the subsequent use of a composite, organic filling. Fredian 5 confirms the practice of dentistry-specifically, a pathology-induced intervention-among Late Pleistocene hunter-gatherers. As such, it appears that fundamental perceptions of biomedical knowledge and practice were in place long before the socioeconomic changes associated with the transition to food production in the Neolithic.


Asunto(s)
Caries Dental/terapia , Restauración Dental Permanente/historia , Caries Dental/historia , Caries Dental/patología , Historia de la Odontología , Historia Antigua , Humanos , Incisivo/patología , Italia , Paleopatología
16.
G Ital Med Lav Ergon ; 38(4): 261-264, 2017 01.
Artículo en Italiano | MEDLINE | ID: mdl-29916607

RESUMEN

OBJECTIVES: The principal purpose of this epidemiological cross-sectional study was to evaluate the frequency of foot problems associated with the wearing of safety footwear (SFW). METHODS: We examined 509 workers from 12 separate metal-working factories, representing all workers employed in these factories. All subjects wore SFW on a daily basis. The study was based on an interviewer-administered questionnaire and a clinical examination of the feet, with particular attention to skin lesions. RESULTS: 81% of the workers had at least one foot problem. The most frequently reported shoe concern was the hot/wet conditions inside the SFW (42%), followed by weight (27.5%), fit (22.9%) with narrowness (19%) and poor sole flexibility (16.3%). CONCLUSIONS: Preventive measures should be implemented to reduce the risk associated with SFW. To achieve this goal, it is necessary on one hand to improve the comfort of SFW from a physiological and ergonomic point of view and, on the other hand, to make an appropriate choice of this personal protective device from the various brands and models available on the market.


Asunto(s)
Enfermedades del Pie/epidemiología , Enfermedades del Pie/etiología , Metalurgia/estadística & datos numéricos , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/etiología , Zapatos/efectos adversos , Piel/lesiones , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
17.
J Environ Manage ; 167: 196-205, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26686072

RESUMEN

Aquifer contamination with diesel fuel is a worldwide environmental problem, and related available remediation technologies may not be adequately efficient, especially for the simultaneous treatment of both solid and water phases. In this paper, a lab-scale 2.45 GHz microwave (MW) treatment of an artificially diesel-contaminated aquifer was applied to investigate the effects of operating power (160, 350 and 500 W) and time on temperature profiles and contaminant removal from both solid and water phases. Results suggest that in diesel-contaminated aquifer MW remediation, power significantly influences the final reachable temperature and, consequently, contaminant removal kinetics. A maximum temperature of about 120 °C was reached at 500 W. Observed temperature values depended on the simultaneous irradiation of both aquifer grains and groundwater. In this case, solid phase heating is limited by the maximum temperature that interstitial water can reach before evaporation. A minimal residual diesel concentration of about 100 mg kg(-1) or 100 mg L(-1) was achieved by applying a power of 500 W for a time of 60 min for the solid or water phase, respectively. Measured residual TPH fractions showed that MW heating resulted in preferential effects of the removal of different TPH molecular weight fractions and that the evaporation-stripping phenomena plays a major role in final contaminant removal processes. The power low kinetic equation shows an excellent fit (r(2) > 0.993) with the solid phase residual concentration observed for all the powers investigated. A maximum diesel removal of 88 or 80% was observed for the MW treatment of the solid or water phase, respectively, highlighting the possibility to successfully and simultaneously remediate both the aquifer phases. Consequently, MW, compared to other biological or chemical-physical treatments, appears to be a better choice for the fast remediation of diesel-contaminated aquifers.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Gasolina , Microondas , Contaminantes Químicos del Agua , Agua Subterránea/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación
18.
J Biol Chem ; 289(30): 21003-21015, 2014 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-24904056

RESUMEN

Streptococcus agalactiae (group B Streptococcus or GBS) is a common cause of invasive infections in newborn infants and adults. The ability of GBS to bind human fibrinogen is of crucial importance in promoting colonization and invasion of host barriers. We characterized here a novel fibrinogen-binding protein of GBS, designated FbsC (Gbs0791), which is encoded by the prototype GBS strain NEM316. FbsC, which bears two bacterial immunoglobulin-like tandem repeat domains and a C-terminal cell wall-anchoring motif (LPXTG), was found to be covalently linked to the cell wall by the housekeeping sortase A. Studies using recombinant FbsC indicated that it binds fibrinogen in a dose-dependent and saturable manner, and with moderate affinity. Expression of FbsC was detected in all clinical GBS isolates, except those belonging to the hypervirulent lineage ST17. Deletion of fbsC decreases NEM316 abilities to adhere to and invade human epithelial and endothelial cells, and to form biofilm in vitro. Notably, bacterial adhesion to fibrinogen and fibrinogen binding to bacterial cells were abolished following fbsC deletion in NEM316. Moreover, the virulence of the fbsC deletion mutant and its ability to colonize the brain were impaired in murine models of infection. Finally, immunization with recombinant FbsC significantly protected mice from lethal GBS challenge. In conclusion, FbsC is a novel fibrinogen-binding protein expressed by most GBS isolates that functions as a virulence factor by promoting invasion of epithelial and endothelial barriers. In addition, the protein has significant immunoprotective activity and may be a useful component of an anti-GBS vaccine.


Asunto(s)
Proteínas Bacterianas/inmunología , Fibrinógeno/inmunología , Interacciones Huésped-Patógeno/inmunología , Infecciones Estreptocócicas/inmunología , Streptococcus agalactiae/fisiología , Factores de Virulencia/inmunología , Animales , Adhesión Bacteriana/genética , Adhesión Bacteriana/inmunología , Proteínas Bacterianas/genética , Células CACO-2 , Modelos Animales de Enfermedad , Células Endoteliales/inmunología , Células Endoteliales/microbiología , Células Endoteliales/patología , Células Epiteliales/inmunología , Células Epiteliales/microbiología , Células Epiteliales/patología , Fibrinógeno/genética , Humanos , Ratones , Unión Proteica/genética , Unión Proteica/inmunología , Infecciones Estreptocócicas/genética , Vacunas Estreptocócicas/genética , Vacunas Estreptocócicas/inmunología , Factores de Virulencia/genética
19.
J Immunol ; 191(4): 1873-82, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23863905

RESUMEN

Newborns and infants present a higher susceptibility to infection than adults, a vulnerability associated with deficiencies in both the innate and adaptive immune systems. Innate immune receptors are sensors involved in the recognition and elimination of microbes that play a pivotal role at the interface between innate and adaptive immunity. Pentraxin 3 (PTX3), the prototypic long pentraxin, is a soluble pattern recognition receptor involved in the initiation of protective responses against selected pathogens. Because neonates are generally resistant to these pathogens, we suspected that PTX3 may be provided by a maternal source during the early life times. We observed that human colostrum contains high levels of PTX3, and that mammary epithelial cell and CD11b(+) milk cells constitutively produce PTX3. Interestingly, PTX3 given orally to neonate mice was rapidly distributed in different organs, and PTX3 ingested during lactation was detected in neonates. Finally, we observed that orally administered PTX3 provided protection against Pseudomonas aeruginosa lung infection in neonate mice. Therefore, breastfeeding constitutes, during the early life times, an important source of PTX3, which actively participates in the protection of neonates against infections. In addition, these results suggest that PTX3 might represent a therapeutic tool for treating neonatal infections and support the view that breastfeeding has beneficial effects on the neonates' health.


Asunto(s)
Lactancia Materna , Proteína C-Reactiva/fisiología , Calostro/química , Recién Nacido/inmunología , Leche Humana/química , Neumonía Bacteriana/prevención & control , Infecciones por Pseudomonas/prevención & control , Componente Amiloide P Sérico/fisiología , Administración Oral , Adulto , Animales , Animales Recién Nacidos , Mama/citología , Proteína C-Reactiva/administración & dosificación , Proteína C-Reactiva/análisis , Proteína C-Reactiva/biosíntesis , Proteína C-Reactiva/farmacocinética , Antígeno CD11b/análisis , Línea Celular , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Endotoxinas/farmacología , Endotoxinas/toxicidad , Células Epiteliales/metabolismo , Femenino , Humanos , Lactancia , Activación de Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Leche Humana/citología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Proteínas del Tejido Nervioso/biosíntesis , Componente Amiloide P Sérico/administración & dosificación , Componente Amiloide P Sérico/análisis , Componente Amiloide P Sérico/farmacocinética , Organismos Libres de Patógenos Específicos , Distribución Tisular
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