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1.
Conserv Biol ; 37(6): e14148, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37424356

RESUMO

Civilizations, including ancient ones, have shaped global ecosystems in many ways through coevolution of landscapes and humans. However, the cultural legacies of ancient and lost civilizations are rarely considered in the conservation of the Eurasian steppe biome. We used a data set containing more than 1000 records on localities, land cover, protection status, and cultural values related to ancient steppic burial mounds (kurgans); we evaluated how these iconic and widespread landmarks can contribute to grassland conservation in the Eurasian steppes, which is one of the most endangered biomes on Earth. Using Bayesian logistic generalized regressions and proportional odds logistic regressions, we examined the potential of mounds to preserve grasslands in landscapes with different levels of land-use transformation. We also compared the conservation potential of mounds inside and outside protected areas and assessed whether local cultural values support the maintenance of grasslands on them. Kurgans were of great importance in preserving grasslands in transformed landscapes outside protected areas, where they sometimes acted as habitat islands that contributed to habitat conservation and improved habitat connectivity. In addition to steep slopes hindering ploughing, when mounds had cultural value for local communities, the probability of grassland occurrence on kurgans almost doubled. Because the estimated number of steppic mounds is about 600,000 and similar historical features exist on all continents, our results may be applicable at a global level. Our results also suggested that an integrative socioecological approach in conservation might support the positive synergistic effects of conservation, landscape, and cultural values.


Contribución de los valores culturales para la conservación esteparia en los antiguos montículos funerarios de Eurasia Resumen Las civilizaciones modernas y antiguas han moldeado de muchas maneras los ecosistemas globales mediante la coevolución del paisaje y la humanidad. Sin embargo, pocas veces se considera el legado cultural de las civilizaciones perdidas o antiguas para la conservación del bioma de la estepa euroasiática. Usamos un conjunto de datos que contiene más de 1,000 registros de las localidades, cobertura del suelo, estado de protección y valores culturales relacionados con los antiguos montículos funerarios de esta estepa (kurgans). Después analizamos cómo estos símbolos icónicos y distribuidos extensamente pueden contribuir a la conservación de los pastizales en la estepa euroasiática, uno de los biomas en mayor peligro de extinción. Analizamos el potencial de conservación de los montículos en paisajes con diferentes niveles de transformación en el uso de suelo mediante regresiones logísticas generalizadas bayesianas y regresiones logísticas de probabilidades proporcionales. También comparamos el potencial de conservación de los montículos dentro y fuera de las áreas protegidas y evaluamos si los valores culturales locales conservan los pastizales dentro de estas mismas áreas. Los kurgans fueron de gran importancia para la conservación de los pastizales en los paisajes transformados ubicados fuera de las áreas protegidas, en donde llegaron a fungir como hábitats aislados que contribuyeron a la conservación y conectividad del hábitat. Además de que las pendientes pronunciadas impiden el arado, cuando los montículos contaban con valor cultural para las comunidades locales, la probabilidad de que el pastizal se ubicara sobre un kurgan casi se duplicó. Ya que se estima que el número de montículos esteparios ronda los 6,000 y que rasgos históricos similares existen en todos los continentes, nuestros resultados pueden aplicarse a nivel global. Nuestros resultados también sugieren que una estrategia socio-ecológica integradora para la conservación podría respaldar los efectos sinérgicos positivos de la conservación, el paisaje y los valores culturales.


Assuntos
Biodiversidade , Ecossistema , Humanos , Conservação dos Recursos Naturais/métodos , Teorema de Bayes , Pradaria
2.
J Environ Manage ; 295: 113053, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34175510

RESUMO

The high nature conservation value of floodplain ecosystems is severely threatened by invasive alien species. Besides adversely affecting native biodiversity, these species also pose a major threat from a wider socio-ecological perspective (e.g. 'roughness' increases flood risk). Finding options to control dense shrub layers consisting of invasive alien species is therefore of high priority for multipurpose management. We studied cattle grazing impacts on the cover, composition and diversity of the herb and shrub layers in floodplain poplar plantations along the Tamis river, Serbia. Non-grazed, moderately grazed, intensively grazed and resting place stands were sampled in five locations in three sampling points. Non-grazed stands had substantially higher cover of invasive alien shrub species (on average 65%) than moderately and intensively grazed stands, and resting places (5.17, 0.02 and 0.00%, respectively), but without considerable differences between the grazing intensity categories. The number of invasive alien species in the shrub layer decreased considerably from non-grazed to intensively grazed stands. Species composition in the herb layer changed from non-grazed to intensively grazed stands, while resting places differed substantially from the other categories. Total species richness, richness of native generalist herbaceous grassland species, and the cover of palatable grasses were the highest in moderately and intensively grazed stands. Our results suggest that cattle grazing in floodplains is effective at controlling invasive alien shrub species. Furthermore, continuous moderate or intensive grazing would contribute to multifunctional management of invaded floodplains by enhancing local biodiversity, reducing flood risk, and providing additional grazing areas for the local community.


Assuntos
Ecossistema , Espécies Introduzidas , Animais , Biodiversidade , Bovinos , Inundações , Sérvia
3.
BMC Anesthesiol ; 17(1): 98, 2017 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-28738837

RESUMO

BACKGROUND: The aim of the present work was to assess cerebral hemodynamic changes in a porcine model of E.coli induced fulminant sepsis. METHODS: Nineteen healthy female Hungahib pigs, 10-12 weeks old, randomly assigned into two groups: Control (n = 9) or Septic Group (n = 10). In the Sepsis group Escherichia coli culture suspended in physiological saline was intravenously administrated in a continuously increasing manner according to the following protocol: 2 ml of bacterial culture suspended in physiological saline was injected in the first 30 min, then 4 ml of bacterial culture was administered within 30 min, followed by infusion of 32 ml bacterial culture for 2 h. Control animals received identical amount of saline infusion. Systemic hemodynamic parameters were assessed by PiCCo monitoring, and cerebral hemodynamics by transcranial Doppler sonography (transorbital approach) in both groups. RESULTS: In control animals, systemic hemodynamic variables and cerebral blood flow velocities and pulsatility indices were relatively stable during the entire procedure. In septic animals shock developed in 165 (IQR: 60-255) minutes after starting the injection of E.coli solution. Blood pressure values gradully decreased, whereas pulse rate increased. A decrease in cardiac index, an increased systemic vascular resistance, and an increased stroke volume variation were observed. Mean cerebral blood flow velocity in the middle cerebral artery did not change during the procedure, but pulsatility index significantly increased. CONCLUSIONS: There is vasoconstriction at the level of the cerebral arterioles in the early phase of experimental sepsis that overwhelmes autoregulatory response. These results may serve as additional pathophysiological information on the cerebral hemodynamic changes occurring during the septic process and may contribute to a better understanding of the pathomechanism of septic encephalopathy.


Assuntos
Circulação Cerebrovascular/fisiologia , Escherichia coli/patogenicidade , Sepse/microbiologia , Sepse/fisiopatologia , Animais , Feminino , Hemodinâmica , Distribuição Aleatória , Suínos , Ultrassonografia Doppler Transcraniana
4.
Biol Rev Camb Philos Soc ; 98(6): 2307-2319, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37646107

RESUMO

The prevailing paradigm about the Quaternary ecological and evolutionary history of Central European ecosystems is that they were repeatedly impoverished by regional extinctions of most species during the glacial periods, followed by massive recolonizations from southern and eastern refugia during interglacial periods. Recent literature partially contradicts this view and provides evidence to re-evaluate this Postglacial Recolonization Hypothesis and develop an alternative one. We examined the long-term history of the flora of the Carpathian (Pannonian) Basin by synthesising recent advances in ecological, phylogeographical, palaeoecological and palaeoclimatological research, and analysing the cold tolerance of the native flora of a test area (Hungary, the central part of the Carpathian Basin). We found that (1) many species have likely occurred there continuously since before the Last Glacial Maximum (LGM); (2) most of the present-day native flora (1404 species, about 80%) can occur in climates as cold as or colder than the LGM (mean annual temperature ≤+3.5°C); and (3) grasslands and forests can be species-rich under an LGM-like cold climate. These arguments support an alternative hypothesis, which we call the Flora Continuity Hypothesis. It states that long-term continuity of much of the flora in the Carpathian Basin is more plausible than regional extinctions during the LGM followed by massive postglacial recolonizations. The long-term continuity of the region's flora may have fundamental implications not only for understanding local biogeography and ecology (e.g. the temporal scale of processes), but also for conservation strategies focusing on protecting ancient species-rich ecosystems and local gene pools.


Assuntos
Ecossistema , Variação Genética , Filogenia , Europa (Continente) , Filogeografia
5.
Clin Hemorheol Microcirc ; 79(2): 245-255, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-28550242

RESUMO

BACKGROUND: Flap hypoperfusion or ischemia-reperfusion (I/R) may occur during preparation-transposition procedures and by postoperative thrombotic complications. Behind the microcirculatory disturbances micro-rheological alterations are also supposed. OBJECTIVE: We aimed to investigate the groin flap I/R with following-up micro-rheological parameters. METHODS: Anesthetized rats were subjected to Control or I/R groups. Groin flaps were prepared bilaterally, pedicled on the superficial epigastric vessels. In the Control group the flaps were re-sutured after one hour, while in I/R group microvascular clips were applied on the pedicles for 60 minutes, then the flaps were repositioned. Besides daily wound control, before the operation and on the 1st, 3rd, 5th, 7th and 14th postoperative days blood samples were collected for testing red blood cell (RBC) deformability (rotational ektacytometry) and aggregation (light-transmission aggregometry). RESULTS: RBC deformability significantly worsened by the 3rd-7th postoperative day in I/R group. RBC aggregation enhanced significantly by the 1st day, in I/R group it remained elevated on the 3rd day as well. In a complicated case with unilateral flap necrosis, RBC deformability and aggregation worsening was outlined from its group (base, 1st, 3rd day). CONCLUSION: Wound healing affected micro-rheological parameters in the early postoperative period. Flap I/R exacerbated the alterations. The parameters markedly worsened in case of flap necrosis.


Assuntos
Virilha , Traumatismo por Reperfusão , Animais , Modelos Animais de Doenças , Eritrócitos , Seguimentos , Isquemia , Microcirculação , Ratos , Reperfusão
6.
Acta Cir Bras ; 34(12): e201901203, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049184

RESUMO

PURPOSE: Composite flaps used in reconstructive surgery may intra- and postoperatively suffer from hypoperfusion and/or ischemia-reperfusion influencing wound healing. We aimed to follow-up the effect of ischemia on adipocutaneous flaps' wound healing and microcirculation. METHODS: In anesthetized rats groin flaps were formed bilaterally. In Control group the flaps were repositioned and sutured back. In Ischemia-Reperfusion (I/R) group before repositioning and suturing the flap pedicles were clamped for 60 minutes. Laser Doppler (LD) fluxmetry and temperature probes were applied on the cranial, central and caudal flap regions before/after preparation and ischemia, re-suturing, and on the 1st-3rd-5th-7th-14th postoperative days, before the final examinations and biopsies for histology. RESULTS: Flaps' skin temperature quickly recovered after repositioning. LD values were lower in the I/R group, reaching a significant level by the 3rd postoperative day, and remained lowered till the 14th day. The magnitude of alterations differed in the flap regions. Histologically normal wound healing process was seen, except for some I/R flaps, where hypertrophized mammary glands were found. CONCLUSIONS: Short-term ischemia could influence flap microcirculation and wound healing, and may result in hypertrophized mammary glands. Laser Doppler could be used to evaluate intra- and postoperative microcirculatory changes and may have significance in predicting complications.


Assuntos
Procedimentos Cirúrgicos Dermatológicos/efeitos adversos , Microcirculação/fisiologia , Retalho Miocutâneo/irrigação sanguínea , Traumatismo por Reperfusão/complicações , Pele/irrigação sanguínea , Cicatrização/fisiologia , Animais , Biópsia , Temperatura Corporal , Modelos Animais de Doenças , Fluxometria por Laser-Doppler , Masculino , Retalho Miocutâneo/patologia , Período Pós-Operatório , Ratos , Valores de Referência , Traumatismo por Reperfusão/patologia , Reprodutibilidade dos Testes , Pele/patologia , Fatores de Tempo , Resultado do Tratamento
7.
Eur J Med Res ; 24(1): 11, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30760331

RESUMO

BACKGROUND: The aim of the present work was to assess systemic hemodynamic changes using PiCCo monitoring in a porcine model of E. coli-induced fulminant sepsis. METHODS: Thirty-one healthy female Hungahib pigs were randomly assigned into control (n = 15) or septic groups (n = 16). In the sepsis group Escherichia coli culture was intravenously administrated in a continuously increasing manner according to the following protocol: 2 ml of bacterial culture suspended in physiological saline was injected in the first 30 min, then 4 ml of bacterial culture was administered within 30 min, followed by infusion of 32 ml bacterial culture for 2 h. Control animals received identical amount of saline infusion. Systemic hemodynamic parameters were assessed by PiCCo monitoring in both groups. RESULTS: Resting hemodynamic parameters were identical in the two groups. In control animals, systemic hemodynamic variables were relatively stable during the entire procedure. In septic animals shock developed in 165 (IQR: 60-255) min after starting the injection of E. coli solution. Blood pressure values gradually decreased, whereas pulse rate increased. A decrease in cardiac index, an increased systemic vascular resistance, and a decreased stroke volume variation were observed. CONCLUSIONS: These results may serve as additional pathophysiological information of hemodynamic changes occurring during hypodynamic sepsis and may contribute to a better understanding of the pathomechanism of septic multiple organ failure.


Assuntos
Escherichia coli/fisiologia , Hemodinâmica/fisiologia , Sepse/microbiologia , Sepse/fisiopatologia , Animais , Pressão Sanguínea , Modelos Animais de Doenças , Feminino , Coração/fisiopatologia , Frequência Cardíaca , Injeções Intravenosas , Volume Sistólico , Suspensões , Suínos , Resistência Vascular
8.
Clin Hemorheol Microcirc ; 61(3): 479-96, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25536919

RESUMO

The pathophysiology of hemorheological and microcirculatory disturbances in septic process -mostly during the early hours- still not clarified in all the details, yet. In anesthetized pigs living E. coli (ATCC 25922 strain) was administered intravenously with an increasing concentration and the animals were observed for 8 hours. Before the intervention and in every 2 hours arterial (cannulated femoral artery) and venous (cannulated external jugular vein) blood samples were collected for hemorheological laboratory tests: blood and plasma viscosity, ESR, leukocyte anti-sedimentation rate, erythrocyte deformability (together with osmoscan parameters) and erythrocyte aggregation (using light-transmission and laser back-scattering methods) Control animals were stable over the 8-hour anesthesia, while septic animals died by the 6th hours in a fulminant sepsis. Over the experimental period, the tendency of impairment in erythrocyte deformability (together with osmotic gradient ektacytometry parameters) and the controversial decreasing of erythrocyte aggregation values (declining all aggregation index values, elongating t1/2) were well detected in this porcine model during the early hours (4- 6) of fulminant sepsis. The in vitro effect of these bacteria on erythrocytes' micro-rheological parameter was similar: decreasing red blood cell deformability and lowering aggregation. Further studies are needed to clarify the early micro-rheological changes of bacteremia and the developing sepsis.


Assuntos
Inflamação/sangue , Animais , Cateterismo , Agregação Eritrocítica , Deformação Eritrocítica , Índices de Eritrócitos , Escherichia coli , Microcirculação , Reologia , Sepse , Suínos
9.
Acta Cir Bras ; 30(7): 470-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26270138

RESUMO

PURPOSE: In the pathophysiology of sepsis tissue perfusion dysfunction is a crucial driving force. Thus the early recognition is highly important. Concerning the early hours of bacteremia, and the systemic inflammatory response reaction leading to sepsis we aimed to investigate the micro- and macrocirculatory changes. METHODS: In 20 juvenile Hungahib pigs were anesthetized and the femoral artery and external jugular vein were prepared unilaterally and cannulated. For assisted ventilation tracheostomy was performed. In Sepsis group (n=11) live E. coli was intravenously administered (increasing concentration, 9.5x10∧6 in 3h). In Control group (n=9) bacteria-free saline was administered at the same volume. Modified shock index (MSI), core and skin temperature, and skin microcirculation (laser Doppler) were measured before inducing bacteremia then hourly for 4h. RESULTS: In Control group parameters were stable, while six animals in the Sepsis group died before the 4th hour. Core and skin temperature did not show significant alterations. In Sepsis group microcirculation showed a large impairment already by the 1st hour, while in MSI only by the 3rd hour. CONCLUSION: During bacteremia and the early phase of sepsis microcirculatory impairment can be detected soon, even hours before the deterioration in hemodynamic parameters in this porcine model.


Assuntos
Bacteriemia/fisiopatologia , Hemodinâmica/fisiologia , Microcirculação/fisiologia , Temperatura Cutânea/fisiologia , Pele/irrigação sanguínea , Animais , Modelos Animais de Doenças , Infecções por Escherichia coli/fisiopatologia , Feminino , Fluxometria por Laser-Doppler , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Choque Séptico/fisiopatologia , Suínos , Fatores de Tempo
10.
Acta cir. bras ; 34(12): e201901203, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1054686

RESUMO

Abstract Purpose Composite flaps used in reconstructive surgery may intra- and postoperatively suffer from hypoperfusion and/or ischemia-reperfusion influencing wound healing. We aimed to follow-up the effect of ischemia on adipocutaneous flaps' wound healing and microcirculation. Methods In anesthetized rats groin flaps were formed bilaterally. In Control group the flaps were repositioned and sutured back. In Ischemia-Reperfusion (I/R) group before repositioning and suturing the flap pedicles were clamped for 60 minutes. Laser Doppler (LD) fluxmetry and temperature probes were applied on the cranial, central and caudal flap regions before/after preparation and ischemia, re-suturing, and on the 1st-3rd-5th-7th-14th postoperative days, before the final examinations and biopsies for histology. Results Flaps' skin temperature quickly recovered after repositioning. LD values were lower in the I/R group, reaching a significant level by the 3rd postoperative day, and remained lowered till the 14th day. The magnitude of alterations differed in the flap regions. Histologically normal wound healing process was seen, except for some I/R flaps, where hypertrophized mammary glands were found. Conclusions Short-term ischemia could influence flap microcirculation and wound healing, and may result in hypertrophized mammary glands. Laser Doppler could be used to evaluate intra- and postoperative microcirculatory changes and may have significance in predicting complications.


Assuntos
Animais , Masculino , Ratos , Pele/irrigação sanguínea , Cicatrização/fisiologia , Traumatismo por Reperfusão/complicações , Procedimentos Cirúrgicos Dermatológicos/efeitos adversos , Retalho Miocutâneo/irrigação sanguínea , Microcirculação/fisiologia , Período Pós-Operatório , Valores de Referência , Pele/patologia , Fatores de Tempo , Biópsia , Temperatura Corporal , Traumatismo por Reperfusão/patologia , Reprodutibilidade dos Testes , Resultado do Tratamento , Fluxometria por Laser-Doppler , Modelos Animais de Doenças , Retalho Miocutâneo/patologia
11.
Acta cir. bras ; 30(7): 470-477, 07/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-754986

RESUMO

PURPOSE: In the pathophysiology of sepsis tissue perfusion dysfunction is a crucial driving force. Thus the early recognition is highly important. Concerning the early hours of bacteremia, and the systemic inflammatory response reaction leading to sepsis we aimed to investigate the micro- and macrocirculatory changes. METHODS: In 20 juvenile Hungahib pigs were anesthetized and the femoral artery and external jugular vein were prepared unilaterally and cannulated. For assisted ventilation tracheostomy was performed. In Sepsis group (n=11) live E. coli was intravenously administered (increasing concentration, 9.5x10∧6 in 3h). In Control group (n=9) bacteria-free saline was administered at the same volume. Modified shock index (MSI), core and skin temperature, and skin microcirculation (laser Doppler) were measured before inducing bacteremia then hourly for 4h. RESULTS: In Control group parameters were stable, while six animals in the Sepsis group died before the 4th hour. Core and skin temperature did not show significant alterations. In Sepsis group microcirculation showed a large impairment already by the 1st hour, while in MSI only by the 3rd hour. CONCLUSION: During bacteremia and the early phase of sepsis microcirculatory impairment can be detected soon, even hours before the deterioration in hemodynamic parameters in this porcine model. .


Assuntos
Animais , Feminino , Bacteriemia/fisiopatologia , Hemodinâmica/fisiologia , Microcirculação/fisiologia , Temperatura Cutânea/fisiologia , Pele/irrigação sanguínea , Modelos Animais de Doenças , Infecções por Escherichia coli/fisiopatologia , Fluxometria por Laser-Doppler , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Suínos , Choque Séptico/fisiopatologia , Fatores de Tempo
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