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1.
Heliyon ; 10(8): e29356, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644898

RESUMO

Landfills play a key role as greenhouse gas (GHGs) emitters, and urgently need assessment and management plans development to swiftly reduce their climate impact. In this context, accurate emission measurements from landfills under different climate and management would reduce the uncertainty in emission accounting. In this study, more than one year of long-term high-frequency data of CO2 and CH4 fluxes were collected in two Italian landfills (Giugliano and Case Passerini) with contrasting management (gas recovery VS no management) using eddy covariance (EC), with the aim to i) investigate the relation between climate drivers and CO2 and CH4 fluxes at different time intervals and ii) to assess the overall GHG balances including the biogas extraction and energy recovery components. Results indicated a higher net atmospheric CO2 source (5.7 ± 5.3 g m2 d-1) at Giugliano compared to Case Passerini (2.4 ± 4.9 g m2 d-1) as well as one order of magnitude higher atmospheric CH4 fluxes (6.0 ± 5.7 g m2 d-1 and 0.7 ± 0.6 g m2 d-1 respectively). Statistical analysis highlighted that fluxes were mainly driven by thermal variables, followed by water availability, with their relative importance changing according to the time-interval considered. The rate of change in barometric pressure (dP/dt) influenced CH4 patterns and magnitude in the classes ranging from -1.25 to +1.25 Pa h-1, with reduction when dP/dt > 0 and increase when dP/dt < 0, whilst a clear pattern was not observed when all dP/dt classes were analyzed. When including management, the total atmospheric GHG balance computed for the two landfills of Giugliano and Case Passerini was 174 g m2 d-1 and 79 g m2 d-1 respectively, of which 168 g m2 d-1 and 20 g m2 d-1 constituted by CH4 fluxes.

2.
Sci Total Environ ; 842: 156843, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35750179

RESUMO

Urban afforestation is considered a promising nature-climate solution that may contribute to achieve climate neutrality by 2050, since it can increase C-storage and C-sequestration, whilst providing further multiple ecosystem services for citizens. However, the quantification of the CO2 sequestration capacity that may be provided by an urban forest as well as the capacity to impact the city-level C-balance and offset anthropogenic emissions is a complex issue. Methodological approaches, quantity and quality of information contained in urban tree database, and the level of detail of the planned urban forest can strongly influence the estimation of C-sequestration potential offered by urban forests. In this work, an integrated framework based on emission inventory, tree species/morphology and ecosystem modelling has been proposed for the city of Prato, Italy, a representative medium size European city to: i) evaluate the current C-sequestration capacity of urban trees; ii) upscale such capacity with different afforestation scenarios, iii) compare the sink capacity offered by ecosystems with current and projected anthropogenic emissions. Results indicated that the green areas within the Municipality of Prato can sequester 33.1 ktCO2 yr-1 under actual conditions and 51.0 ktCO2 yr-1 under the afforestation scenario which maximize the CO2 sequestration capacity, offsetting the 7.1 % and 11 % of the total emissions (465.8 ktCO2 yr-1), respectively. This study proves that, in the various afforestation scenarios tested, the contribution of urban afforestation to the municipality carbon balance is negligible and that carbon neutrality can only be reached by the substantial decarbonization of emission sectors.


Assuntos
Sequestro de Carbono , Carbono , Dióxido de Carbono , Ecossistema , Florestas , Árvores
3.
Transl Med UniSa ; 19: 42-48, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31360666

RESUMO

We developed and tested an innovative physical training method in older adults that embeds the gym program into everyday life in the most conservative way possible. Physical training was included in the activities of local parishes where older women from Southern Italy spend most of their free time and was delivered by trained physical therapists with the support of an ICT tool known as CoCo. 113 older women (aged 72.0 [69.0-75.0] years) noncompliant to conventional exercise programs participated to the study. 57 of them underwent the final anthropometric assessment and 50 the final physical tests. In study completers handgrip strength and physical performance evaluated with the chair-stand, the two minutes step and the chair-sit and -reach tests significantly improved. Quality of life as evaluated with the EuroQol-5dimension (EQ-5D) questionnaire improved as well. In conclusion, a training program designed to minimally impact on life habits of older people is effective in improving fitness in patients noncompliant to other to physical exercise programs.

4.
Sci Rep ; 8(1): 13821, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30217983

RESUMO

A minute fraction of atmospheric particles exert a disproportionate effect on the phase of mixed-phase clouds by acting as ice-nucleating particles (INPs). To understand the effects of these particles on weather and climate, both now and into the future, we must first develop a quantitative understanding of the major INP sources worldwide. Previous work has demonstrated that aerosols such as desert dusts are globally important INPs, but the role of biogenic INPs is unclear, with conflicting evidence for their importance. Here, we show that at a temperate site all INPs active above -18 °C at concentrations >0.1 L-1 are destroyed on heating, consistent with these INPs being of biological origin. Furthermore, we show that a global model of desert dust INPs dramatically underestimates the measured INP concentrations, but is consistent with the thermally-stable component. Notably, the heat sensitive INPs are active at temperatures where shallow cloud layers in Northern Europe are frequently observed to glaciate. Hence, we suggest that biogenic material is important for primary ice production in this region. The prevalence of heat sensitive, most likely biogenic, INPs in this region highlights that, as a community, we need to quantify the sources and transport of these particles as well as determine their atmospheric abundance across the globe and at cloud altitudes.

5.
Sci Rep ; 8(1): 7340, 2018 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-29743608

RESUMO

Members of the hominins - namely the so-called 'australopiths' and the species of the genus Homo - are known to possess short and deep mandibles and relatively small incisors and canines. It is commonly assumed that this suite of traits evolved in early members of the clade in response to changing environmental conditions and increased consumption of though food items. With the emergence of Homo, the functional meaning of mandible shape variation is thought to have been weakened by technological advancements and (later) by the control over fire. In contrast to this expectation, we found that mandible shape evolution in hominins is exceptionally rapid as compared to any other primate clade, and that the direction and rate of shape change (from the ape ancestor) are no different between the australopiths and Homo. We deem several factors including the loss of honing complex, canine reduction, and the acquisition of different diets may have concurred in producing such surprisingly high evolutionary rates. This study reveals the evolution of mandibular shape in hominins has strong morpho-functional and ecological significance attached.


Assuntos
Hominidae/anatomia & histologia , Hominidae/fisiologia , Mandíbula/anatomia & histologia , Animais , Evolução Biológica , Fósseis , Humanos , Mandíbula/patologia
6.
Heredity (Edinb) ; 118(2): 154-159, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27649620

RESUMO

Southern Italy has a long history of human occupation and passage of different cultures since the Early Holocene. Repeated, ancient introductions of pigs in several geographic areas in Europe make it difficult to understand pig translocation and domestication in Italy. The archeozoological record may provide fundamental information on this, hence shedding light on peopling and on trading among different ancient cultures in the Mediterranean. Yet, because of the scanty nature of the fossil record, ancient remains from human-associated animals are somewhat rare. Fortunately, ancient DNA analysis as applied to domestic species proved to be a powerful tool in revealing human migrations. Herein, we analyzed 80-bp fragment of mitochondrial DNA control region from 27 Sus scrofa ancient samples retrieved from Southern Italian and Sardinian archeological sites, spanning in age from the Mesolithic to the Roman period. Our results surprisingly indicate the presence of the Near Eastern haplotype Y1 on both Italy's major islands (Sardinia and Sicily) during the Bronze Age, suggesting the seaborne transportation of domestic pigs by humans at least during 1600-1300 BC. The presence of the Italian E2 clade in domestic contexts shows that the indigenous wild boar was effectively domesticated or incorporated into domestic stocks in Southern Italy during the Bronze Age, although the E2 haplotype has never been found in modern domestic breeds. Pigs belonging to the endemic E2 clade were thus traded between the Peninsula and Sardinia by the end of the second millennium BC and this genetic signature is still detected in Sardinian feral pigs.


Assuntos
Distribuição Animal , DNA Antigo , Sus scrofa/genética , Animais , Animais Domésticos/genética , Comércio , DNA Mitocondrial/genética , Domesticação , Haplótipos , Migração Humana , Itália , Análise de Sequência de DNA , Sicília , Meios de Transporte
7.
Sci Rep ; 6: 30965, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27507121

RESUMO

Animal clades tend to follow a predictable path of waxing and waning during their existence, regardless of their total species richness or geographic coverage. Clades begin small and undifferentiated, then expand to a peak in diversity and range, only to shift into a rarely broken decline towards extinction. While this trajectory is now well documented and broadly recognised, the reasons underlying it remain obscure. In particular, it is unknown why clade extinction is universal and occurs with such surprising regularity. Current explanations for paleontological extinctions call on the growing costs of biological interactions, geological accidents, evolutionary traps, and mass extinctions. While these are effective causes of extinction, they mainly apply to species, not clades. Although mass extinctions is the undeniable cause for the demise of a sizeable number of major taxa, we show here that clades escaping them go extinct because of the widespread tendency of evolution to produce increasingly specialised, sympatric, and geographically restricted species over time.


Assuntos
Extinção Biológica , Especiação Genética , Modelos Biológicos , Animais , Biodiversidade , Evolução Biológica , Bases de Dados Factuais , Fósseis , Cadeias de Markov , Paleontologia , Simpatria
8.
J Hum Evol ; 95: 1-12, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27260171

RESUMO

The dispersal of Homo erectus out of Africa at some 1.9 million years ago is one of the most important, crucial, and yet controversial events in human evolution. Current opinions about this episode expose the contrast between those who see H. erectus as a highly social, cooperative species seeking out new ecological opportunities to exploit, and those preferring a passive, climate driven explanation for such an event. By using geostatistics techniques and probabilistic models, we characterised the ecological context of H. erectus dispersal, from its East African origin to the colonization of Eurasia, taking into account both the presence of other large mammals and the physical characteristics of the landscape as potential factors. Our model indicated that H. erectus followed almost passively the large herbivore fauna during its dispersal. In Africa, the dispersal was statistically associated with the presence of large freshwater bodies (Rift Valley Lakes). In Eurasia, the presence of H. erectus was associated with the occurrence of geological outcrops likely yielding unconsolidated flint. During the early phase of dispersal, our model indicated that H. erectus actively avoided areas densely populated by large carnivores. This pattern weakened as H. erectus dispersed over Europe, possibly because of the decreasing presence of carnivores there plus the later acquisition of Acheulean technology. During this later phase, H. erectus was associated with limestone and shaley marl, and seems to have been selecting for high-elevation sites. While our results do not directly contradict the idea that H. erectus may have been an active hunter, they clearly point to the fact that predator avoidance may have conditioned its long-distance diffusion as it moved outside Africa. The modelled dispersal route suggests that H. erectus remained preferentially associated with low/middle latitude (i.e., comparatively warm) sites throughout its colonization history.


Assuntos
Distribuição Animal , Evolução Biológica , Hominidae/fisiologia , África , Animais , Migração Humana , Modelos Biológicos
9.
Transl Med UniSa ; 13: 19-28, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27042429

RESUMO

The aim of this paper is to give an insight on how physical activity can be defined, parameterized and measured in older adults and on different options to deal with citizen physical activity promotion at European level. Three relevant aspects are highlighted: When talking about physical activity, two different aspects are often unfairly mixed up: "physical activity" and "physical capacity". Physical activity, is referred to as the level of physical activity someone is actually performing in daily life.Physical capacity is referred to as the maximum physical activity a person can perform.Both physical activity and physical capacity can be expressed in different dimensions such as time, frequency, or type of activity with the consequence that there are many tools and techniques available. In order to support people to choose an appropriate instrument in their everyday practice a list of 9 criteria that are considered important is defined.Older adults score differently across the various physical dimensions, so strategies to promote physical activity should consider individual differences, in order to adapt for these variations.

10.
Proc Biol Sci ; 280(1750): 20122244, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23173207

RESUMO

A classic question in evolutionary biology concerns the tempo and mode of lineage evolution. Considered variously in relation to resource utilization, intrinsic constraints or hierarchic level, the question of how evolutionary change occurs in general has continued to draw the attention of the field for over a century and a half. Here we use the largest species-level phylogeny of Coenozoic fossil mammals (1031 species) ever assembled and their body size estimates, to show that body size and taxonomic diversification rates declined from the origin of placentals towards the present, and very probably correlate to each other. These findings suggest that morphological and taxic diversifications of mammals occurred hierarchically, with major shifts in body size coinciding with the birth of large clades, followed by taxonomic diversification within these newly formed clades. As the clades expanded, rates of taxonomic diversification proceeded independently of phenotypic evolution. Such a dynamic is consistent with the idea, central to the Modern Synthesis, that mammals radiated adaptively, with the filling of adaptive zones following the radiation.


Assuntos
Evolução Biológica , Tamanho Corporal , Fósseis , Mamíferos/anatomia & histologia , Paleontologia/métodos , Animais , Mamíferos/genética , Fenótipo , Filogenia , Análise de Regressão
11.
Am Nat ; 179(3): 328-37, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22322221

RESUMO

Cope's rule is the trend toward increasing body size in a lineage over geological time. The rule has been explained either as passive diffusion away from a small initial body size or as an active trend upheld by the ecological and evolutionary advantages that large body size confers. An explicit and phylogenetically informed analysis of body size evolution in Cenozoic mammals shows that body size increases significantly in most inclusive clades. This increase occurs through temporal substitution of incumbent species by larger-sized close relatives within the clades. These late-appearing species have smaller spatial and temporal ranges and are rarer than the incumbents they replace, traits that are typical of ecological specialists. Cope's rule, accordingly, appears to derive mainly from increasing ecological specialization and clade-level niche expansion rather than from active selection for larger size. However, overlain on a net trend toward average size increase, significant pulses in origination of large-sized species are concentrated in periods of global cooling. These pulses plausibly record direct selection for larger body size according to Bergmann's rule, which thus appears to be independent of but concomitant with Cope's.


Assuntos
Adaptação Biológica/fisiologia , Evolução Biológica , Tamanho Corporal/fisiologia , Fósseis , Mamíferos/fisiologia , Modelos Biológicos , Animais , Clima , Especiação Genética , Mamíferos/genética , Filogenia , Especificidade da Espécie
12.
Biol Lett ; 8(1): 64-6, 2012 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-21849310

RESUMO

Species response to environmental change may vary from adaptation to the new conditions, to dispersal towards territories with better ecological settings (known as habitat tracking), and to extinction. A phylogenetically explicit analysis of habitat tracking in Caenozoic large mammals shows that species moving over longer distances during their existence survived longer. By partitioning the fossil record into equal time intervals, we showed that the longest distance was preferentially covered just before extinction. This supports the idea that habitat tracking is a key reaction to environmental change, and confirms that tracking causally prolongs species survival. Species covering longer distances also have morphologically less variable cheek teeth. Given the tight relationship between cheek teeth form and habitat selection in large mammals, this supports the well-known, yet little tested, idea that habitat tracking bolsters morphological stasis.


Assuntos
Adaptação Biológica/fisiologia , Migração Animal , Ecossistema , Meio Ambiente , Extinção Biológica , Fósseis , Mamíferos/fisiologia , Filogenia , Animais , Comportamento de Retorno ao Território Vital/fisiologia , Mamíferos/anatomia & histologia , Mamíferos/genética , Especificidade da Espécie , Dente/anatomia & histologia
13.
Proc Biol Sci ; 278(1724): 3474-81, 2011 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21471111

RESUMO

The acquisition of hypsodont molars is often regarded as a key innovation in the history of ruminant ungulates. Hypsodont ruminants diversified rapidly during the later Neogene, circa 15-2 Myr ago, and came to dominate the ruminant fossil record in terms of species diversity. Here we show that hypsodont clades had higher speciation and diversification rates than other clades. Hypsodont species had, on average, shorter stratigraphic durations, smaller range size and lower occupancy than non-hypsodont species. Within hypsodont clades, some species were very common and acquired large geographical ranges, whereas others were quite rare and geographically limited. We argue that hypsodont clades diversified in an adaptive radiation-like fashion, with species often splitting cladogenetically while still in the expansive phase of their occupancy history.


Assuntos
Evolução Biológica , Ruminantes/genética , Dente/anatomia & histologia , Animais , Ásia , Europa (Continente) , Extinção Biológica , Fósseis , Especiação Genética , Análise dos Mínimos Quadrados , Modelos Lineares , Filogenia , Ruminantes/anatomia & histologia , Ruminantes/classificação
14.
Regul Pept ; 148(1-3): 26-32, 2008 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-18410972

RESUMO

Brain Natriuretic Peptide (BNP), besides retaining vasodilatory, diuretic and natriuretic properties, is a vasoactive hormone that it is also involved in several cardiac diseases as well as severe sepsis and septic shock. All these conditions are characterized by an ongoing inflammatory response consisting in a complex interaction of pleiotropic mediators derived from plasma or cells, including monocytes and macrophages. However, the relationship between this hormone and inflammation remains to be elucidated. Therefore, the aim of the present study was to evaluate a possible BNP immunomodulatory activity on macrophages. Our results demonstrate that BNP regulates the production of major inflammatory molecules, such as reactive oxygen- and nitrogen species (ROS and RNS), leukotriene B(4) (LTB(4)), prostaglandin E(2) (PGE(2)); modulates the cytokines (TNF-alpha, IL-12 and IL-10) profile, and affects cell motility. These results furnish novel and brand-new proofs on BNP ability of modulating the production of inflammatory mediators in macrophages whose role has broad implications in inflammatory states where increased BNP levels have been reported.


Assuntos
Mediadores da Inflamação/metabolismo , Macrófagos/efeitos dos fármacos , Peptídeo Natriurético Encefálico/farmacologia , Ácido Araquidônico/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Dinoprostona/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Leucotrieno B4/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
15.
Inflammation ; 30(5): 167-77, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17594136

RESUMO

Excessive leukocyte proliferation and proinflammatory mediators release represent common phenomena in several chronic inflammatory diseases. Multiple evidences identify lysophosphatidic acid (LPA), a small lipid endowed with pleiotropic activities, as an important modulator of both proliferation and activation of different cell types involved in several inflammation-associated pathologies. However, its possible role on monocyte proinflammatory activation is not fully understood yet. Aim of the present study was to investigate LPA effects on THP-1 cells in terms of proliferation, reactive oxygen intermediates (ROI) production and release of arachidonic acid-derived inflammatory mediators. Actually, LPA significantly increased both DNA synthesis and ROI production as well as prostaglandin E(2) release and the upregulation of LPA(3) receptor expression. These findings identified LPA as both a growth factor and a triggering mediator of proinflammatory response in THP-1 cells.


Assuntos
Ácido Araquidônico/metabolismo , Proliferação de Células , Mediadores da Inflamação/metabolismo , Lisofosfolipídeos/metabolismo , Monócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Replicação do DNA , Dinoprostona/metabolismo , Ativação Enzimática , Humanos , Inflamação/metabolismo , Isoxazóis/farmacologia , Leucotrieno B4/metabolismo , Monócitos/efeitos dos fármacos , NADPH Oxidases/metabolismo , Propionatos/farmacologia , RNA Mensageiro/metabolismo , Receptores de Ácidos Lisofosfatídicos/antagonistas & inibidores , Receptores de Ácidos Lisofosfatídicos/genética , Receptores de Ácidos Lisofosfatídicos/metabolismo , Fatores de Tempo , Regulação para Cima
16.
Inflammation ; 29(4-6): 129-40, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17089191

RESUMO

Excessive leukocyte proliferation and proinflammatory mediators release represent common phenomena in several chronic inflammatory diseases. Multiple evidences identify lysophosphatidic acid (LPA), a small lipid endowed with pleiotropic activities, as an important modulator of both proliferation and activation of different cell types involved in several inflammation-associated pathologies. However, its possible role on monocyte proinflammatory activation is not fully understood yet. Aim of the present study was to investigate LPA effects on THP-1 cells in terms of proliferation, reactive oxygen intermediates (ROI) production and release of arachidonic acid-derived inflammatory mediators. Actually, LPA significantly increased both DNA synthesis and ROI production as well as prostaglandin E(2) release and the upregulation of LPA(3) receptor expression. These findings identified LPA as both a growth factor and a triggering mediator of proinflammatory response in THP-1 cells.


Assuntos
Lisofosfolipídeos/farmacologia , Monócitos/citologia , Monócitos/metabolismo , Ácido Araquidônico/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Dinoprostona/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Isoxazóis/farmacologia , Leucotrieno B4/metabolismo , Lisofosfolipídeos/administração & dosagem , Monócitos/efeitos dos fármacos , NADPH Oxidases/metabolismo , Propionatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de Superfície Celular/metabolismo
17.
J Lipid Res ; 42(1): 96-105, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11160370

RESUMO

Evidence is given that the heart of the cardiomyopathic UM-X7.1 hamster has a lipid composition different from that of the same tissue isolated from animals of the Syrian hamster parent strain. Also, noncardiac tissues from cardiomyopathic and healthy hamsters exhibit significant compositional differences. On the basis of these preliminary observations, a comparative study of the hepatic biosynthesis of lipids in cardiomyopathic and healthy Syrian hamsters was undertaken. The results obtained indicate that the cardiomyopathic hamster is characterized by a generalized disturbance of lipid metabolism. In particular, the fatty acid synthase and stearoyl-CoA desaturase activities were significantly lower in the liver of UM-X7.1 hamsters than in age-matched healthy controls fed the same diet. Northern blot analysis of the mRNAs encoding the two enzymatic proteins and the "lipogenic" S14 nuclear protein indicated that the transcription of the respective genes was impaired in UM-X7.1.Short-term dietary manipulations modulated the expression of the above-mentioned genes both in cardiomyopathic and healthy animals. However, dietary carbohydrates were less effective in inducing the expression of lipogenic enzymes in UM-X7.1 liver than healthy controls. The main determinant of the metabolic defect pointed out in the present work appears to be represented by the low insulin level detectable in the plasma of the cardiomyopathic hamster.-Vecchini, A., L. Binaglia, M. Bibeau, M. Minieri, F. Carotenuto, and P. Di Nardo. Insulin deficiency and reduced expression of lipogenic enzymes in cardiomyopathic hamster. J. Lipid Res. 2001. 42: 96;-105.


Assuntos
Cardiomiopatias/enzimologia , Ácido Graxo Sintases/genética , Insulina/deficiência , Fosfolipídeos/biossíntese , Estearoil-CoA Dessaturase/genética , Fatores Etários , Animais , Cardiomiopatias/dietoterapia , Cardiomiopatias/metabolismo , Cricetinae , Dieta com Restrição de Gorduras , Carboidratos da Dieta/uso terapêutico , Ácido Graxo Sintases/metabolismo , Expressão Gênica , Ventrículos do Coração/química , Insulina/sangue , Fígado/química , Fígado/enzimologia , Mesocricetus , Modelos Animais , Proteínas Nucleares , Fosfolipídeos/análise , Fosfolipídeos/farmacocinética , Proteínas/genética , RNA Mensageiro/análise , Traçadores Radioativos , Estearoil-CoA Dessaturase/metabolismo , Fatores de Transcrição
19.
Hepatogastroenterology ; 38(2): 149-53, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1855773

RESUMO

In this study we have investigated various morphofunctional features of gallbladder mucosa in patients with uncomplicated cholelithiasis. The histological changes, endocrine cell types and their distribution, and mucin-producing cells were characterized by immunocytochemistry and mucin histochemistry; moreover, we attempted to correlate these findings to the number and size of gallbladder stones and the type of bacteria present in the bile. Our results indicate that, despite similar clinical parameters, a wide range of histological changes can occur in the gallbladder mucosa of these patients. Moreover, the presence of certain endocrine and mucin-producing cell types in so-called "pyloric metaplasia" led us to hypothesize that this finding may be a trivial event in the gallbladder epithelium.


Assuntos
Colelitíase/patologia , Vesícula Biliar/patologia , Mucinas/biossíntese , Epitélio/patologia , Feminino , Vesícula Biliar/metabolismo , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Mucosa/patologia , Muco/metabolismo
20.
G Chir ; 11(10): 561-4, 1990 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-2288845

RESUMO

To assess the potential structural changes of the biliary tree and liver in patients with extrahepatic biliary obstruction, the resected specimens of 20 patients operated for benign biliary stricture were evaluated by means of immunocytochemical and histological methods. Furthermore, liver biopsies were taken for the same purposes. The results showed that in the dilated segment of the hepatic duct proximal to the stricture, innervation was greatly reduced or completely absent with associated advanced morphological and histological changes and high intrabiliary pressure levels. Similar findings were observed in the liver biopsies, too. These biopsies showed advanced morphological and histological changes associated with reduced innervation. By contrast, the nondilated segment of the hepatic duct, distal to the obstruction, showed normal innervation, normal morphology and histology and normal levels of intrabiliary pressure. The present study provides evidence that in cases of extrahepatic biliary obstruction, there are advanced pathological changes in the biliary tree associated with innervation impairment. These structural changes are associated with functional changes in both the liver and the biliary tree. Such functional changes represent a threat to the patient, particularly if major surgery is required. Increased biliary pressure appears to be a major cause of the development of these changes. Biliary drainage, either surgical or endoscopic, is indicated as the only alternative to reduce intrabiliary pressure and to contribute to a reversal of these structural and functional changes.


Assuntos
Bile/fisiologia , Colelitíase/fisiopatologia , Colestase Extra-Hepática/fisiopatologia , Ducto Hepático Comum/fisiopatologia , Biópsia , Colelitíase/patologia , Colestase Extra-Hepática/patologia , Ducto Hepático Comum/inervação , Ducto Hepático Comum/patologia , Humanos , Pressão
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