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1.
Sci Rep ; 13(1): 177, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604573

RESUMO

Here, we present the results related to a new unique terrestrial ecosystem found in an englacial hypersaline brine found in Northern Victoria Land (Antarctica). Both the geochemistry and microbial (prokaryotic and fungal) diversity revealed an unicity with respect to all the other known Antarctic brines and suggested a probable ancient origin mainly due a progressive cryoconcentration of seawater. The prokaryotic community presented some peculiarities, such as the occurrence of sequences of Patescibacteria (which can thrive in nutrient-limited water environments) or few Spirochaeta, and the presence of archaeal sequences of Methanomicrobia closely related to Methanoculleus, a methanogen commonly detected in marine and estuarine environments. The high percentage (35%) of unassigned fungal taxa suggested the presence of a high degree of undiscovered diversity within a structured fungal community (including both yeast and filamentous life forms) and reinforce the hypothesis of a high degree of biological uniqueness of the habitat under study.


Assuntos
Ecossistema , Euryarchaeota , Regiões Antárticas , Sais , Bactérias
2.
Science ; 371(6533): 1038-1041, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674491

RESUMO

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

3.
Nature ; 563(7731): 365-368, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30429552

RESUMO

Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3 and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4-6, astrometry7,8 and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future.

4.
Mar Environ Res ; 112(Pt B): 20-32, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26231593

RESUMO

As a part of a wider project on fisheries ecology, several biological and environmental parameters were monitored during two oceanographic cruises (BANSIC 2012 and NOVESAR 2013) in the Sicily Channel, which connects the Western and Eastern Mediterranean basins. The prokaryotic abundances and biomass as well as hydrolysis rates on organic matter were investigated in the euphotic layer of a retention area for fish larval stages including anchovy (Engraulis encrasicolus, Linnaeus, 1758) with the aim to investigate the different biogeochemical signatures in two seasonal conditions. The environmental parameters, particulate organic carbon and nitrogen together with heterotrophic production were also measured. Results showed significant increases for most of the studied parameters with increasing temperature during summer. This had effects on the Carbon cycle and recycling of nutrients; in fact total prokaryotic abundance and biomass, as well as carbon hydrolyzed by two enzymes (Leucine aminopeptidase and ß-glucosidase), increased significantly during summer. Conversely Alkaline phosphatase activity, Chlorophyll concentration and Oxygen increased during winter. The same environmental parameters affected also the presence of fish eggs. Moreover high percentages of free enzymes (i.e., enzymes not associated with cells) were measured, accounting for percentages variable from 12 to 95 % of the total enzymatic activity, with values generally higher in summer than in winter. In this oligotrophic environment, the prokaryotic biomass was supported by the C hydrolyzed by enzymatic activities. The ratio between the hydrolyzed C and prokaryotic biomass was higher in winter than in summer, indicating that alkaline phosphatase activity contribute to an efficient incorporation of C into biomass in winter.


Assuntos
Archaea/fisiologia , Fenômenos Fisiológicos Bacterianos , Biomassa , Água do Mar/química , Itália , Mar Mediterrâneo , Estações do Ano
5.
Microb Ecol ; 67(1): 45-56, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24158689

RESUMO

This study examines the effects of temporal changes on microbial parameters in a brackish aquatic ecosystem. To this aim, the abundances of prokaryotes and vibrios together with the rates of enzymatic hydrolysis of proteins by leucine aminopeptidase (LAP), polysaccharides by ß-glucosidase (GLU) and organic phosphates by alkaline phosphatase (AP), heterotrophic prokaryotic production (HPP), respiration (R), were seasonally investigated, during a 2-year period in the coastal area of Cape Peloro (Messina, Italy), constituted by two brackish lakes (Faro and Ganzirri). In addition, physical and chemical parameters (temperature, salinity, nutrients) and particulate organic carbon and nitrogen (POC, PN) were measured. The influence of multiple factors on prokaryotic abundances and activities was analysed. The results showed that Cape Peloro area is characterised by high seasonal variability of the microbial parameters that is higher than the spatial one. Combined changes in particulate matter and temperature (T), could explain the variability in vibrios abundance, GLU and R activities in both lakes, indicating a direct stimulation of the warm season on the heterotrophic prokaryotic metabolism. Positive correlations between T (from 13.3 to 29.6 °C) and HPP, LAP, AP, POC, PN are also observed in Ganzirri Lake. Moreover, the trophic status index and most of the microbial parameters show significant seasonal differences. This study demonstrates that vibrios abundance and microbial activities are responsive to the spatial and seasonal changes of examined area. The combined effects of temperature and trophic conditions on the microbial parameters lead us to suggest their use as potential indicators of the prokaryotic response to climate changes in temperate brackish areas.


Assuntos
Ecossistema , Processos Heterotróficos , Estações do Ano , Vibrio/crescimento & desenvolvimento , Microbiologia da Água , Fosfatase Alcalina/metabolismo , Carbono/química , Itália , Lagos/microbiologia , Leucil Aminopeptidase/metabolismo , Nitrogênio/química , Salinidade , Temperatura , beta-Glucosidase/metabolismo
6.
Z Gerontol Geriatr ; 42(4): 328-35, 2009 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-19618229

RESUMO

OBJECTIVES: Patients with dysphagia whose food intake is inadequate and who may compromise their airways need to receive nasogastric (NG) or gastrostomic (PEG) feeding. There are controversial discussions about the best time for intervention and the best method. Each approach has its advantages and disadvantages. Further research is required to assess the optimum method of treating patients with dysphagia. A retrospective study was undertaken to investigate the influence of functional dysphagia therapy with or without PEG feeding. METHODS: A total of 164 patients with dysphagia were investigated in a center for geriatric medicine (EGZB) within one year. Patients were divided into two groups: those with PEG (group 1, n=59) and those without (group 2, n=105). Both groups received functional training (training of oral motor skills and sensation, compensatory swallowing techniques) by speech-language therapists.Geriatric basic assessment was used. Speech-language therapists also evaluated language, speech and swallowing disorders pre- and post-training. Diet modification for oral intake altering viscosity and texture of foods and liquids was used. Additional data on the time between being admitted to hospital and receiving a PEG tube, the hospitalization period, the number of complications and mortality were collected. RESULTS: Both groups benefited from functional dysphagia therapy. The patients of group 2 showed a significant improvement in functional oral intake post-treatment. In most of the cases, diet modification improved from pasty consistency to firm meals. Swallowing abilities were much better than those of the more severely disabled patients of group 1. Group 1 still needed PEG feeding post-treatment but could also take in some food orally. However even the patients of group 1 showed a significant increase in functional oral intake.Group 2 also showed significantly stronger improvements in communication abilities and speech intelligibility after training compared to the severely disabled patients of group 1.In terms of the clinical outcome of group 1 it was demonstrated that the sooner a PEG was placed, the more significantly functional oral intake improved. The results of a multiple regression analysis showed a small but nevertheless significant association between an early supply of PEG and improvement of functional oral intake which had been achieved by functional dysphagia therapy.Significantly more complications and significantly higher mortality occurred in group 1 (PEG feeding) compared to group 2 (exclusively oral feeding). CONCLUSION: The treatment of dysphagia in the elderly requires a multi-professional setting, differentiated assessment and functional training of oral motor skills and sensation and swallowing techniques. Compared to patients with severe dysphagia, however, patients with mild to moderate dysphagia benefit most from functional training. The results reveal the importance of precise and early diagnosis of swallowing disorders in order to introduce PEG supply early in cases of persistent dysphagia.


Assuntos
Transtornos de Deglutição/enfermagem , Transtornos de Deglutição/reabilitação , Nutrição Enteral/métodos , Gastrostomia/métodos , Intubação Gastrointestinal/métodos , Recuperação de Função Fisiológica , Idoso , Feminino , Humanos , Masculino , Resultado do Tratamento
7.
Tissue Antigens ; 66(1): 64-6, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15982263

RESUMO

We report here the identification and characterization of a novel human leucocyte antigen (HLA)-DPB1 allele that was subsequently named HLA-DPB1*0302 by the WHO Nomenclature Committee. HLA-DPB1*0302 was identified in a single Sicilian individual by a combination of sequence-specific primers, reverse line sequence-specific oligonucleotide probing and DNA sequencing-based typing. The DPB1*0302 allele is most similar to the DPB1*3101 allele, differing by a single mismatch at nucleotide position 301 (T to G).


Assuntos
Alelos , Antígenos HLA-DP/genética , Sequência de Bases , Primers do DNA/química , Éxons , Cadeias beta de HLA-DP , Humanos , Dados de Sequência Molecular , Oligonucleotídeos/genética , Homologia de Sequência do Ácido Nucleico , Sicília
8.
New Microbiol ; 24(3): 265-71, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11497084

RESUMO

Respiratory rates in two areas of the North Adriatic Sea were studied in the context of a PRISMA II Project, with the aim of quantifying the oxidative processes occurring in the frontal system caused by strong riverine discharge. In the northern area, higher respiratory rates and seasonal variations occurred with respect to the southern area. On average, respiratory activity sustained the oxidation of 66.9 nM C h(-1) inside the front and 24.4 nM C h(-1) outside the front. In conclusion, organic matter oxidation inside the front resulted 2.7 times higher than outside the front. Oxidative metabolism in the Northern Adriatic Sea appears mainly governed by river inputs.


Assuntos
Consumo de Oxigênio , Plâncton/metabolismo , Análise de Variância , Animais , Dióxido de Carbono/metabolismo , Transporte de Elétrons , Água Doce , Mar Mediterrâneo , Estações do Ano , Água do Mar/química , Água do Mar/parasitologia
9.
Leukemia ; 15(6): 976-80, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11417486

RESUMO

An increase of angiogenesis has been shown in idiopathic myelofibrosis with myeloid metaplasia (MMM) by microvessel density count method but evaluation of circulating angiogenic factors is still incomplete. In 31 patients affected by MMM and in 12 healthy subjects we evaluated the serum levels of VEGF (vascular endothelial growth factor) and correlated VEGF with clinical and laboratory features of disease. We found that MMM patients had circulating VEGF concentrations much higher than controls (Median 1208 ng/ml vs 138 ng/ml, P < 0.0001). No correlation was found between VEGF and Hb, WBC, PLT, LDH, creatinine, bone marrow cellularity, fibrosis, splenomegaly, hepatomegaly, and therapy. However, in the subgroup of patients with a normal or low VEGF concentration, a direct correlation between VEGF and platelet count (r = 0.90, P = 0.002) was detected. Moreover, patients with a platelet count < 300 x 10(9)/l had VEGF serum levels lower than patients with a higher PLT count (median VEGF 864 vs 1557 pg/ml, P = 0.001). In six patients and in eight controls we also had the opportunity to measure VEGF in the plasma and we calculated that VEGF concentration was much higher in platelet-rich than in platelet-poor plasma and that platetets of MMM patients contained four times more VEGF than those of healthy controls. These results indicate that VEGF is overproduced in MMM, thus confirming an increased angiogenic activity. Platelets are probably a major source of VEGF in MMM but not the only one.


Assuntos
Fatores de Crescimento Endotelial/sangue , Linfocinas/sangue , Mielofibrose Primária/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Medula Óssea/patologia , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/sangue , Neovascularização Patológica/etiologia , Plasma/química , Contagem de Plaquetas , Mielofibrose Primária/complicações , Baço/patologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
10.
Haematologica ; 85(8): 800-5, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10942925

RESUMO

BACKGROUND AND OBJECTIVES: To study the role of some soluble factors in the process of angiogenesis that accompanies multiple myeloma (MM). DESIGN AND METHODS: The concentrations of three well-known angiogenic peptides, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and hepatocyte growth factor (HGF) were evaluated by an ELISA method. All of these factors were measured in the plasma obtained from peripheral blood (PB) and bone marrow (BM) aspirates of 34 patients affected by plasma cell disorders. This series included one patient with a solitary extramedullary plasmacytoma, 17 patients with MM at diagnosis, and 16 with previously treated MM. RESULTS: In all the patients, the concentration of each angiogenic factor was higher in bone marrow than in peripheral blood. Mean values of the three angiogenic factors in BM or in PB were lower in stage I than stage II-III. One patient with extramedullary solitary myeloma had high levels of VEGF and bFGF but this increase was not found in the other 6 patients with extramedullary disease when compared with patients without extramedullary disease. VEGF and bFGF did not correlate with each other while HGF showed a weak correlation with VEGF and a stronger one with bFGF. Moreover, VEGF correlated with features of disease activity, such as C-reactive protein, and 2-microglobulin, while both bFGF and HGF showed an inverse correlation with albumin level. No correlation was found between VEGF, bFGF and HGF levels and age, M protein level, osteolytic lesions, or percentage of BM plasma cells. Since angiogenic factors may be released by normal cells in response to hypoxia, we also evaluated erythropoietin (EPO) levels (which correlate with the hypoxic stimulus) both in PB and BM plasma of these patients but none of the measured angiogenic factors correlated with EPO levels. Interpretation and Conclusions. Several soluble factors may play a role in the angiogenic activity described in MM but their contribution to the progression of disease may be different. The finding of higher levels of these factors in BM than in PB might indicate that the bone marrow environment is their major source. Concentrations of angiogenic factors parallel the activity of disease and are independent of the hypoxic stimulus.


Assuntos
Medula Óssea/química , Fatores de Crescimento Endotelial/análise , Fator 2 de Crescimento de Fibroblastos/análise , Fator de Crescimento de Hepatócito/análise , Linfocinas/análise , Mieloma Múltiplo/fisiopatologia , Proteínas de Neoplasias/análise , Neovascularização Patológica/metabolismo , Corticosteroides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores , Medula Óssea/patologia , Contagem de Células , Fatores de Crescimento Endotelial/sangue , Ensaio de Imunoadsorção Enzimática , Eritropoetina/análise , Feminino , Fator 2 de Crescimento de Fibroblastos/sangue , Fator de Crescimento de Hepatócito/sangue , Humanos , Interferon-alfa/uso terapêutico , Linfocinas/sangue , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Proteínas de Neoplasias/sangue , Estadiamento de Neoplasias , Células-Tronco Neoplásicas/patologia , Plasmócitos/patologia , Plasmocitoma/metabolismo , Plasmocitoma/fisiopatologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
12.
Am J Hum Genet ; 64(4): 949-62, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10090880

RESUMO

Familial Mediterranean fever (FMF) is a recessive disorder characterized by episodes of fever with serositis or synovitis. The FMF gene (MEFV) was cloned recently, and four missense mutations were identified. Here we present data from non-Ashkenazi Jewish and Arab patients in whom we had not originally found mutations and from a new, more ethnically diverse panel. Among 90 symptomatic mutation-positive individuals, 11 mutations accounted for 79% of carrier chromosomes. Of the two mutations that are novel, one alters the same residue (680) as a previously known mutation, and the other (P369S) is located in exon 3. Consistent with another recent report, the E148Q mutation was observed in patients of several ethnicities and on multiple microsatellite haplotypes, but haplotype data indicate an ancestral relationships between non-Jewish Italian and Ashkenazi Jewish patients with FMF and other affected populations. Among approximately 200 anonymous Ashkenazi Jewish DNA samples, the MEFV carrier frequency was 21%, with E148Q the most common mutation. Several lines of evidence indicate reduced penetrance among Ashkenazi Jews, especially for E148Q, P369S, and K695R. Nevertheless, E148Q helps account for recessive inheritance in an Ashkenazi family previously reported as an unusual case of dominantly inherited FMF. The presence of three frequent MEFV mutations in multiple Mediterranean populations strongly suggests a heterozygote advantage in this geographic region.


Assuntos
Febre Familiar do Mediterrâneo/genética , Haplótipos/genética , Heterozigoto , Judeus/genética , Mutação/genética , Penetrância , Substituição de Aminoácidos/genética , Árabes/genética , Armênia/etnologia , Sequência de Bases , Cromossomos Humanos/genética , Proteínas do Citoesqueleto , Éxons/genética , Febre Familiar do Mediterrâneo/epidemiologia , Feminino , Frequência do Gene , Genes Recessivos/genética , Humanos , Israel , Itália , Masculino , Repetições de Microssatélites/genética , Dados de Sequência Molecular , Linhagem , Proteínas/genética , Pirina , Turquia/etnologia
13.
New Microbiol ; 19(3): 243-9, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8841040

RESUMO

Microplankton respiration in the euphotic zone in the Central Mediterranean Sea was calculated by ETS activity measurements. Distribution of ETSa in the studied area appeared homogeneous and comparable with previous data measured in the Mediterranean Sea. A typical ETSa value for euphotic Mediterranean waters of 0.14 meq O2 h-1 m-3 was calculated. The investigated area supports a metabolic CO2 production of 70 g C m-2 y-1. When compared with regional productivity, the respiration budget in the euphotic zone accounted for 22% of carbon fixed. ETSa appeared a useful assay for the study of evolutive history of the water masses in the Mediterranean Sea.


Assuntos
Plâncton/metabolismo , Água do Mar , Animais , Dióxido de Carbono/metabolismo , Transporte de Elétrons , Mar Mediterrâneo , Consumo de Oxigênio
14.
J Appl Bacteriol ; 80(6): 611-6, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8698662

RESUMO

The autotrophic ammonium-oxidizing bacterium Nitrosococcus oceanus was studied in the brackish lake of Ganzirri by cultural and immunofluorescent methods. The preparation of the specific antiserum in rabbits is reported. The polyclonal antiserum for Nitrosococcus oceanus cross-reacted with other ammonia oxidizing strains, but not with other marine bacteria. Temporal changes were determined by taking monthly water samples from a station 6 m deep and the distribution in sediments was investigated in four stations. Isolation of a strain of Nitrosococcus sp. was obtained from a sediment sample collected in December. The abundance of Nitrosococcus spp. bacteria correlated positively with particulate organic carbon (POC), particulate organic nitrogen (PON), temperature and total bacteria, whereas there was a negative relationship with oxygen tension. No correlation was found between immunofluorescent and MPN counts of Nitrosococcus spp. bacteria.


Assuntos
Bradyrhizobiaceae/isolamento & purificação , Microbiologia da Água , Animais , Anticorpos Antibacterianos/imunologia , Especificidade de Anticorpos , Antígenos de Bactérias/análise , Bradyrhizobiaceae/imunologia , Contagem de Colônia Microbiana , Feminino , Imunofluorescência , Coelhos , Água do Mar
15.
J Am Soc Mass Spectrom ; 7(11): 1151-60, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24203078

RESUMO

The primary gas-phase reactions between methanol, ethanol, propan-1-ol, propan-2-ol, and 2-methyipropan-2-ol and the isovalent rare earth metal ions Sc(+), Y(+), and Lu(+) generated by laser desorption-ionization of metal targets have been investigated by using a Fourier transform ion cyclotron resonance mass spectrometer. The three metal ions react exothermically with all the alcohols. The overall reactivity is controlled by the high oxophilicity of these metals, and the primary metallated ions obtained are principally oxygenated species. However, the number and the nature of these primary products depends on the electronic configuration of the metal ions as well as on the class and the principal chain length of alcohols. The order of reactivity is Y(+) > Sc(+) > Lu(+). The Y(+) and Sc(+) ions principally react via C-O and O-H insertions, whereas Lu+ reacts by direct abstraction or via various five-center electrocyclic mechanisms as a function of the class and the alcohol chain length.

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