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1.
Sci Rep ; 10(1): 21984, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33319781

RESUMEN

The Holocene period (last 11,700 years BP) has been marked by significant climate variability over decadal to millennial timescales. The underlying mechanisms are still being debated, despite ocean-atmosphere-land connections put forward in many paleo-studies. Among the main drivers, involving a cluster of spectral signatures and shaping the climate of north-western Europe, are solar activity, the North Atlantic Oscillation (NAO) varying atmospheric regimes and North Atlantic oceanic gyre dynamics. Over the last 2500 years BP, paleo-environmental signals have been strongly affected by anthropogenic activities through deforestation and land use for crops, grazing, habitations, or access to resources. Palynological proxies (especially pollen grains and marine or freshwater microalgae) help to highlight such anthropogenic imprints over natural variability. Palynological analyses conducted in a macro-estuarine sedimentary environment of north-western France over the last 2500 years BP reveal a huge and atypical 300 year-long arboreal increase between 1700 and 1400 years BP (around 250 and 550 years AD) that we refer to as the '1.7-1.4 ka Arboreal Pollen rise event' or '1.7-1.4 ka AP event'. Interestingly, the climatic 1700-1200 years BP interval coincides with evidence for the withdrawal of coastal societies in Brittany (NW France), in an unfavourable socio-economic context. We suggest that subpolar North Atlantic gyre strengthening and related increasing recurrence of storminess extremes may have affected long-term coastal anthropogenic trajectories resulting in a local collapse of coastal agrarian societies, partly forced by climatic degradation at the end of the Roman Period.

2.
Sci Rep ; 7: 43402, 2017 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-28262720

RESUMEN

Angiosperm mitochondrial genomes (mtDNA) exhibit variable quantities of alien sequences. Many of these sequences are acquired by intracellular gene transfer (IGT) from the plastid. In addition, frequent events of horizontal gene transfer (HGT) between mitochondria of different species also contribute to their expanded genomes. In contrast, alien sequences are rarely found in plastid genomes. Most of the plant-to-plant HGT events involve mitochondrion-to-mitochondrion transfers. Occasionally, foreign sequences in mtDNAs are plastid-derived (MTPT), raising questions about their origin, frequency, and mechanism of transfer. The rising number of complete mtDNAs allowed us to address these questions. We identified 15 new foreign MTPTs, increasing significantly the number of those previously reported. One out of five of the angiosperm species analyzed contained at least one foreign MTPT, suggesting a remarkable frequency of HGT among plants. By analyzing the flanking regions of the foreign MTPTs, we found strong evidence for mt-to-mt transfers in 65% of the cases. We hypothesize that plastid sequences were initially acquired by the native mtDNA via IGT and then transferred to a distantly-related plant via mitochondrial HGT, rather than directly from a foreign plastid to the mitochondrial genome. Finally, we describe three novel putative cases of mitochondrial-derived sequences among angiosperm plastomes.


Asunto(s)
Transferencia de Gen Horizontal , Genoma Mitocondrial , Genoma de Plastidios , Magnoliopsida/genética , Mitocondrias/genética , Plastidios/genética , Arecaceae/clasificación , Arecaceae/genética , Secuencia de Bases , ADN Mitocondrial , Evolución Molecular , Fagaceae/clasificación , Fagaceae/genética , Lamiaceae/clasificación , Lamiaceae/genética , Magnoliopsida/clasificación , Filogenia , Rosaceae/clasificación , Rosaceae/genética
4.
Braz J Biol ; 75(1): 157-64, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25945633

RESUMEN

The choice of sampling gears to assess benthic macroinvertebrate communities depends on environmental characteristics, study objectives, and cost effectiveness. Because of the high foraging capacity and diverse habitats and behaviors of benthophagous fishes, their stomach contents may offer a useful sampling tool in studies of benthic macroinvertebrates, especially in large, deep, fast rivers that are difficult to sample with traditional sediment sampling gear. Our objective was to compare the benthic macroinvertebrate communities sampled from sediments with those sampled from fish stomachs. We collected benthic macroinvertebrates and fish from three different habitat types (backwater, beach, riffle) in the wet season, drying season, and dry season along a single reach of the Grande River (Paraná River Basin, southeast Brazil). We sampled sediments through use of a Petersen dredge (total of 216 grabs) and used gill nets to sample fish (total of 36 samples). We analyzed the stomach contents of three commonly occurring benthophagous fish species (Eigenmannia virescens, Iheringichthys labrosus, Leporinus amblyrhynchus). Chironomids dominated in both sampling methods. Macroinvertebrate taxonomic composition and abundances from fish stomachs differed from those from sediment samples, but less so from riffles than from backwater and beach habitats. Macroinvertebrate taxa from E. virescens stomachs were more strongly correlated with sediment samples from all three habitats than were those from the other two species. The species accumulation curves and higher mean dispersion values, compared with with sediment samples suggest that E. virescens is more efficient than sediment samples and the other fish studied at collecting benthic taxa. We conclude that by analyzing the stomach contents of benthophagous fishes it is possible to assess important characteristics of benthic communities (dispersion, taxonomic composition and diversity). This is especially true for studies that only sample fish assemblages to evaluate aquatic ecosystem impacts. Therefore, this approach can be useful to amplify assessments of human impacts, and to incorporate additional bioindicators.


Asunto(s)
Ecosistema , Monitoreo del Ambiente/métodos , Peces , Contenido Digestivo , Invertebrados/clasificación , Animales , Brasil , Ríos , Estaciones del Año
5.
Intensive Care Med ; 26(1): 31-7, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10663277

RESUMEN

OBJECTIVE: To ascertain if, after an episode of hypotension, unnoticed myocardial necrosis could occur in critical care patients with acute non-cardiac illness and to search for signs of cardiac necrosis. DESIGN: A prospective observational study. SETTING: General intensive care unit (ICU) at a tertiary level hospital. PATIENTS: Thirty-one patients in two groups. Group 1 included 19 patients with severe sepsis/septic shock (ACCP/SCCM Consensus Conference). Group 2 included 12 patients with hypovolemic shock. INTERVENTIONS: Biochemical markers of myocardial necrosis (cardiac troponin I (cTnI), creatine kinase (CK), creatine kinase MB mass (CKMB) and myoglobin) were measured at 12 h (T1), 24 h (T2) and 48 h (T3) after enrollment. A standard 12-lead ECG was recorded upon enrollment (T0) and at T2. Anomalous Q-waves or ST segment depression or elevation was considered diagnostic for acute myocardial infarction (AMI). A hypotensive episode (arterial systolic pressure < 90 mmHg at heart rate > 100 bpm) was considered moderate if it lasted 30-60 min or severe if longer than 60 min. MEASUREMENTS AND RESULTS: At T0 none of the patients had AMI on ECG. At T2 a non-Q AMI developed in five patients. Increased levels of troponin I, myoglobin, CK and CKMB were found in 74.2 %, 96.8 %, 74.2 % and 67.7 % of the patients, respectively. Cardiac troponin I increased in 11 out of 19 septic patients and in all hypovolemic patients. There was a significant difference between the groups (p < 0.05). All biochemical markers increased in relationship to the degree of hypotension with cTnI again showing a significant difference. The longer the hypotensive episode was, the greater was the increase (moderate hypotension: median 1.16; quartiles 0.55-3.44 ng/ml, severe hypotension: median 8.53; quartiles 1.1-20.7 ng/ml; p < 0.05). Abnormal levels of cTnI were more frequent in non-survivors than in survivors (p < 0.05). CONCLUSIONS: Hypotension may cause cardiac damage in critically ill patients with acute non-cardiac diseases as shown by abnormal levels of cTnI. It is likely that a high number of these myocardial necroses may go unnoticed on the ECG.


Asunto(s)
Creatina Quinasa/metabolismo , Hipotensión/complicaciones , Unidades de Cuidados Intensivos , Miocardio/patología , Sepsis/complicaciones , Choque/complicaciones , Troponina I/metabolismo , Anciano , Electrocardiografía , Mortalidad Hospitalaria , Humanos , Isoenzimas , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Mioglobina/metabolismo , Necrosis , Estudios Prospectivos , Sepsis/fisiopatología , Choque/fisiopatología
6.
J Chromatogr A ; 921(2): 147-60, 2001 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-11471798

RESUMEN

In this paper, the use of penicillin G acylase (PGA) as a biocatalyst and as a chiral selector is described. Penicillin G-acylase is an interesting enzyme used in the manufacture of semisynthetic antibiotics and, in particular, in the production of 6-APA by hydrolysis of penicillin G. Five PGA-based HPLC columns have been prepared by using two different silica supports by employing two immobilization methods, namely "in situ" and "in batch". The effects of the immobilization techniques and of different silica pore size on the catalytic properties of the enzyme as well as the applicability of the PGA-bonded stationary phases as chiral selectors for a number of chiral drugs have been investigated. The HPLC columns based on immobilized PGA combine the hydrolytic activity and the chiral recognition properties of PGA, therefore they have been used for the development of a combined reaction-separation system for chiral and achiral substrates.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Enzimas Inmovilizadas/metabolismo , Penicilina Amidasa/metabolismo , Catálisis , Concentración de Iones de Hidrógeno , Hidrólisis , Estereoisomerismo , Especificidad por Sustrato
7.
Environ Pollut ; 48(1): 25-36, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-15092696

RESUMEN

All the eggs, collected in Italy in 1982 and 1983, of two species of passerine birds, three gulls, four terns and the night heron, contained DDE and, with lower frequencies, other organochlorine contaminants. Organochlorines were more concentrated in the species of higher trophic level. DDE contamination showed a decreasing trend from 1978 to 1985 in one passerine, two terns and in the heron. After 1980-1982, the level of contamination was below the critical threshold beyond which reproduction is affected, eggshell thickness was only slightly or not reduced; therefore, the current impact of organochlorines on these birds is probably negligible. Detrimental effects may have occurred during the 1970s, when some of the eggs were contaminated beyond the critical threshold.

8.
G Ital Med Lav Ergon ; 22(1): 52-61; discussion 62-3, 2000.
Artículo en Italiano | MEDLINE | ID: mdl-10771760

RESUMEN

Numerous occupational intoxications (acute, chronic and their sequelae) may affect the central nervous system and result in a wide variety of neuropsychiatric effects, ranging from subtle behavioural disturbances to overt psychosis. Chemicals causing such manifestations include many metals and organometals (Hg, Mn, Pb, Al, Sn), pesticides (organophosphates), compounds utilised in the industrial setting as solvents or intermediates (carbon disulfide, hydrocarbons and their halogenated derivatives), and combustion products (carbon monoxide). Some types of toxic insults may not be reflected in any clinical manifestation. However, this type of damage may render the brain more vulnerable to additional insult or accelerate physiological loss of neurones with ageing. Thus, occupational exposures to chemicals (Al, Pb, organic solvents) might be involved in the causation of neurodegenerative diseases--such as Alzheimer's disease--which are usually labelled as "idiopathic". A careful occupational anamnesis is crucial to diagnose work-related psychiatric manifestations and--consequently--to interrupt the toxic exposure, to start therapy, and to promote insurance compensation.


Asunto(s)
Trastornos Mentales/etiología , Enfermedades Profesionales/inducido químicamente , Aluminio/envenenamiento , Disulfuro de Carbono/envenenamiento , Intoxicación por Monóxido de Carbono , Humanos , Insecticidas/envenenamiento , Intoxicación por Plomo , Intoxicación por Manganeso , Intoxicación por Mercurio , Enfermedades Profesionales/complicaciones , Compuestos Organofosforados , Estaño/envenenamiento
9.
G Ital Med Lav Ergon ; 19(2): 42-9, 1997.
Artículo en Italiano | MEDLINE | ID: mdl-9432312

RESUMEN

Health management of major chemical incidents requires a close collaboration between rescuers (on the disaster site and in the emergency department) and the poison center. The study tested telematic technologies allowing telepresence and teleconsulting, a real time and continuous connection among health care personnel and toxicologists involved in the management of the emergency. The link between the poison center (PC) and the emergency department in the local hospital is provided by a ISDN operating video conferencing system, while the data transmission from the site of the accident to the PC is achieved with a personal computer and GSM cellular data transmission. Toxicological databases and risk assessment software are integrated in the system, to support information sharing. To test such instruments in operative nearly realistic conditions, the main phase of the study has implemented simulated chemical disasters in different locations in Italy. Instruments for telepresence and teleconsulting have been effectively utilized to evaluate from a remote location the scenario and the severity of the accident, by inspecting either specific details or the whole scene, to enable PC guiding the triage of the victims before and after hospitalization, to utilize and share data, such as intervention protocols or patient records, and to document all the activities. In summary, this experience shows that the telematic link allows the toxicologists of the poison center to rapidly understand the situation, and to correctly learn about the conditions of patients with the help of images. The results of this study indicate the valuable benefits of telematic instruments for the health care in case of major chemical disasters occurring in a remote geographical location or in an area which lacks local toxicological experts, where specialized expertise can be achieved by the use of telematic technologies.


Asunto(s)
Centros de Control de Intoxicaciones/organización & administración , Telemedicina/instrumentación , Servicio de Urgencia en Hospital/organización & administración , Humanos , Capacitación en Servicio/organización & administración , Italia , Consulta Remota/instrumentación , Consulta Remota/organización & administración , Telemedicina/organización & administración , Recursos Humanos
10.
Boll Chim Farm ; 128(7-8): 229-31, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2611008

RESUMEN

A simple and rapid high performance liquid chromatographic method was developed for separation and identification of K-hetacillin and Na-dicloxacillin in oily suspensions for veterinary practice. The method is precise, accurate and applicable to the analysis of commercial dosage form.


Asunto(s)
Dicloxacilina/análisis , Penicilinas/análisis , Cromatografía Líquida de Alta Presión , Suspensiones
11.
Breast ; 22(4): 419-24, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23643803

RESUMEN

PURPOSE: We investigated in a single institution series of 124 women with operable breast cancer whether tumor clinicopathological features could predict the 70-gene signature (Mammaprint, MP) results, and whether MP results could help to make decisions for the use of chemotherapy (CT) in patients (pts) with ER positive breast cancer beyond recommendations of international guidelines. RESULTS: Among the 68 ER/PgR positive, HER2 negative tumors, Ki-67 ≥ 20% was the only significant predictor of a high risk-MP among standard clinicopathological features. In candidates for endocrine therapy with undetermined benefit from CT according to international guidelines, MP results would have led to different treatment decisions in 13/46 (28%) and in 20/68 (29%) pts according to NCCN and St. Gallen recommendations, respectively. CONCLUSIONS: Ki-67 independently predicted high risk-MP in ER/PgR positive, HER2 negative tumors. MP results would have led to discordant treatment recommendations in about 30% of cases, generally increasing indication rate for CT. The results of large randomized trials are warranted in order to understand whether we should rely on multigene assays rather than on standard clinicopathological features for treatment decisions.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Antígeno Ki-67/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Anciano , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante/métodos , Estudios de Cohortes , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Receptor ErbB-2/metabolismo , Resultado del Tratamiento
12.
Ecancermedicalscience ; 6: 275, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23130087

RESUMEN

We report the case of a 34-year-old woman affected by breast cancer that had metastasized to the bone. She had been treated with oral cyclophosphamide and methotrexate (metronomic chemotherapy) and achieved 3.5 years of clinical remission. To our knowledge, this is the first description of such a prolonged response to therapy. This case report adds weight to known data on metronomic treatment and supports further investigation of this therapy.

18.
Arch Environ Contam Toxicol ; 51(4): 690-702, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16998633

RESUMEN

The epidermis of vertebrates is the body's principal barrier against environment and its possible contaminants. The presence of keratins, as well as specific detoxifying molecules or enzyme activities, in the various epidermis layers is believed to be involved in providing protection from harmful environmental influences. Anuran integument is poorly hornified and thus permeable to some endogenous and exogenous compounds and thus serves as a good bioindicator of overall environmental conditions. In the present investigation, we studied the epidermis of Rana kl. esculenta adult specimens collected at two different rice fields, relatively unpolluted and heavily polluted, respectively. Environmental pollution was assayed by chemical analysis performed on both sediments and animals. We evaluated the structural aspects of the epidermis at both light and electron microscopy levels and the pattern of keratinization by immunohistochemistry. Furthermore, we studied the activities of some enzymes (acid and alkaline phosphatase, nitric oxide synthase-related nicotinamide adenine dinucleotide phosphate dehydrogenase, glucose-6-phosphate dehydrogenase, catalase, nonspecific esterases, and succinic dehydrogenase) involved mainly in membrane transport, xenobiotics, and oxidative metabolism. Compared with controls, in polluted animals we found the following results: (1) an increase in pollutant levels (i.e., cadmium, mercury, and lead); (2) less keratinized superficial cells in the epidermis; and (3) changes in most enzyme activities in keratinocytes and mitochondria-rich cells (particularly glucose-6-phosphate dehydrogenase and esterases, both important to counteract oxidative and toxic stress). Taken as a whole, the present data indicate the morphofunctional plasticity of the frog epidermis in response to environmental contamination.


Asunto(s)
Epidermis/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Monitoreo del Ambiente , Epidermis/metabolismo , Epidermis/patología , Epidermis/ultraestructura , Femenino , Sedimentos Geológicos , Glucosafosfato Deshidrogenasa/metabolismo , Inmunohistoquímica , Queratinas/análisis , Masculino , Mitocondrias/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Rana esculenta , Especies Reactivas de Oxígeno
19.
Environ Monit Assess ; 118(1-3): 355-68, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16897550

RESUMEN

The rapidly developing Asian countries may face threatening environmental contamination, that however remains largely unassessed. We studied persistent trace elements in three wetlands, Poyang Lake, relatively unpolluted, and Tai Lake, and Pearl River Delta, selected as hotspots of pollution in Central China. We adopted as indicator the Little Egret, a widespread colonial waterbird, and during 1999 and 2000 we collected and analysed the same samples as for a parallel study we conducted in Pakistan, e.g. eggs, body feathers of chicks, prey spontaneously regurgitated by the chicks, and sediments at the areas most used by foraging egrets. The levels of trace-metals at our three study areas were similar, or within the range, of those found in the few other studies for East Asia, with few exceptions. The concentrations of the various elements were below the threshold that may affect the survival or reproduction of the birds, and even the highest concentrations relative to background, i.e. Se in eggs, and Hg in feathers at Pearl Delta, do not pose toxic hazards. In sediments, the levels of trace elements were lower than the critical levels assumed for contaminated soil, except for alarming high levels of As at Poyang. These results do not confirm our expectation, that Poyang was relatively uncontaminated, while Tai and Pearl were polluted. Although trace metal concentration differed significantly among the three study areas, these differences were minor and were not consistent among elements and samples. The bioaccumulation ratios from sediments through prey, feather and egg, were consistent with our previous findings for Pakistan. Only Hg exhibited high bioaccumulation, while Se and Zn had low accumulation, and the other elements no accumulation. This reasserts that feathers of predators such as egrets, may be more sensitive indicators of environmental contamination for the elements subject to bioaccumulation, whereas the sediments or the organisms low in the food chain are better indicators for the other elements.


Asunto(s)
Arsénico/análisis , Aves/metabolismo , Sedimentos Geológicos/análisis , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Animales , Arsénico/metabolismo , China , Dieta , Monitoreo del Ambiente , Plumas/metabolismo , Metales Pesados/metabolismo , Óvulo/metabolismo , Contaminantes Químicos del Agua/metabolismo , Humedales
20.
Farmaco Sci ; 33(11): 849-54, 1978 Nov.
Artículo en Italiano | MEDLINE | ID: mdl-744240

RESUMEN

A new series of N,N-di,sec.butylalkylbenzamides was studied and it was found that some compounds showed particularly interesting selective phytotoxicity comparable with that shown by analogous halogen derivatives.


Asunto(s)
Benzamidas/síntesis química , Herbicidas/síntesis química , Benzamidas/farmacología , Factores de Tiempo
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