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1.
Parasitol Res ; 119(4): 1401-1408, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32130486

RESUMO

Fatty acid-binding proteins (FABPs) are small intracellular proteins that reversibly bind fatty acids and other hydrophobic ligands. In cestodes, due to their inability to synthesise fatty acids de novo, FABPs have been proposed as essential proteins, and thus, as possible drug targets and/or carriers against these parasites. We performed data mining in Echinococcus multilocularis and Echinococcus granulosus genomes in order to test whether this family of proteins is more complex than previously reported. By exploring the genomes of E. multilocularis and E. granulosus, six genes coding for FABPs were found in each organism. In the case of E. granulosus, all of them have different coding sequences, whereas in E. multilocularis, two of the genes code for the same protein. Remarkably, one of the genes (in both cestodes) encodes a FABP with a C-terminal extension unusual for this family of proteins. The newly described genes present variations in their structure in comparison with previously described FABP genes in Echinococcus spp. The coding sequences for E. multilocularis were validated by cloning and sequencing. Moreover, differential expression patterns of FABPs were observed at different stages of the life cycle of E. multilocularis by exploring transcriptomic data from several sources. In summary, FABP family in cestodes is far more complex than previously thought and includes new members that seem to be only present in flatworms.


Assuntos
Echinococcus granulosus/genética , Echinococcus multilocularis/genética , Proteínas de Ligação a Ácido Graxo/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA de Protozoário/genética , Ácidos Graxos/metabolismo , Genoma de Protozoário/genética , Análise de Sequência , Análise de Sequência de DNA , Transcriptoma/genética
2.
Nature ; 496(7443): 57-63, 2013 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-23485966

RESUMO

Tapeworms (Cestoda) cause neglected diseases that can be fatal and are difficult to treat, owing to inefficient drugs. Here we present an analysis of tapeworm genome sequences using the human-infective species Echinococcus multilocularis, E. granulosus, Taenia solium and the laboratory model Hymenolepis microstoma as examples. The 115- to 141-megabase genomes offer insights into the evolution of parasitism. Synteny is maintained with distantly related blood flukes but we find extreme losses of genes and pathways that are ubiquitous in other animals, including 34 homeobox families and several determinants of stem cell fate. Tapeworms have specialized detoxification pathways, metabolism that is finely tuned to rely on nutrients scavenged from their hosts, and species-specific expansions of non-canonical heat shock proteins and families of known antigens. We identify new potential drug targets, including some on which existing pharmaceuticals may act. The genomes provide a rich resource to underpin the development of urgently needed treatments and control.


Assuntos
Adaptação Fisiológica/genética , Cestoides/genética , Genoma Helmíntico/genética , Parasitos/genética , Animais , Evolução Biológica , Cestoides/efeitos dos fármacos , Cestoides/fisiologia , Infecções por Cestoides/tratamento farmacológico , Infecções por Cestoides/metabolismo , Sequência Conservada/genética , Echinococcus granulosus/genética , Echinococcus multilocularis/efeitos dos fármacos , Echinococcus multilocularis/genética , Echinococcus multilocularis/metabolismo , Genes de Helmintos/genética , Genes Homeobox/genética , Proteínas de Choque Térmico HSP70/genética , Humanos , Hymenolepis/genética , Redes e Vias Metabólicas/genética , Terapia de Alvo Molecular , Parasitos/efeitos dos fármacos , Parasitos/fisiologia , Proteoma/genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Taenia solium/genética
3.
Scand J Clin Lab Invest ; 75(3): 213-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25594795

RESUMO

Osmotic gradient ektacytometry (measuring elongation index in the function of osmolality at a constant shear stress) is a sensitive method to analyze red blood cell (RBC) deformability and investigating the optimal osmolality range for the cells in normal or pathophysiological cellular and micro-environmental conditions. However, the methodological conditions are different, since the results are influenced by the applied shear stress (SS). In this study we investigated rat, dog, pig and human blood samples at SS of 1, 2, 3, 5, 10, 20 and 30 Pa. To describe the range being related to the cell deformability, we introduced new calculated parameters obtained from the raw data of the elongation index (EI)-osmolality (O) curves. Our results showed that: (1) Osmoscan data tested at 20 or 30 Pa do not differ significantly from each other; (2) Under SS of 20 Pa the EImax, the O (EImax), the EI min and the area under curve nearly linearly decrease in the function of SS with different slope in rat, dog, pig and human blood; (3) Measurements under 3 Pa SS become unstable; (4) The differences between minimal and maximal EI and the belonging osmolality values, and their ratios, as new calculated parameters (ΔEI, ΔO, ΔEI/ΔO, EImax/EImin and O (EImax)/Omin) can be suitable for further analysis of the osmoscan curves together with other hemorheological parameters describing RBC deformability; and (5) Decreased erythrocyte deformability (by rigidifying with glutaraldehyde) can be reflected well with the following, calculated osmoscan parameters: ΔO, rO, rEI/rO and ΔEI/ΔO.


Assuntos
Eritrócitos/fisiologia , Hemorreologia , Animais , Animais não Endogâmicos , Forma Celular , Cães , Elasticidade , Feminino , Humanos , Masculino , Concentração Osmolar , Ratos , Resistência ao Cisalhamento , Sus scrofa
4.
Chemosphere ; 355: 141701, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38508463

RESUMO

The purpose of this study is investigation of electrocoagulation (EC) as a treatment of municipal wastewater, integrating life cycle impact assessment (LCIA) for assessing its environmental performance of investigated treatment. The study evaluated the effectiveness of EC in removing physico-chemical and microbial parameters using aluminum (Al) and iron (Fe) electrodes in monopolar and bipolar modes. Bipolar arrangement of Al(-)/Al/Al/Al(+) electrodes achieved the highest removals: 70% COD, 72% BOD5 followed by complete elimination of total phosphorous, turbidity and microbial parameters. This treatment was subject to investigation of the influence of reaction time (t = 10-60 min) on removals at higher current density (CD = 3.33 mA/cm2). In order to reduce energy consumption, the same reaction time range was used with a reduced CD = 2.33 mA/cm2. Following removal efficiencies obtained: 47-72% COD (higher CD) and 53-78% (lower CD); 69-75% BOD5 (higher CD) and 55-74% CD (lower CD); 12-21% NH4- (higher CD) and 7-22% NH4- (lower CD). Total P, NO3- and NO2- compounds showed the same removals regardless the CD. Decrease in current density did not influence removals of total suspended matter, turbidity, salinity as well as microbial parameters. The bipolar arrangement of Al(-)/Al/Al/Al(+) electrodes, assuming a lower CD = 2.33 mA/cm2 and t = 30 min, was assessed with the Recipe 2016Midpoint (H) and USEtox v.2 LCIA methods to explore the environmental justification of using EC for wastewater treatment. The LCIA results revealed that the EC process significantly reduces water eutrophication and toxicity for freshwater and marine ecosystems, but has higher impacts in global warming, fossil fuel consumption, human toxicity, acidification, and terrestrial ecotoxicity due to high energy consumption. This can be mainly explained by the assumption in the study that the EC precipitate is dispersed to agricultural soil without any pre-treatment and material recovery, along with relatively high energy consumption during the process.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Humanos , Eliminação de Resíduos Líquidos/métodos , Ecossistema , Eletrocoagulação/métodos , Ferro , Eletrodos , Alumínio , Resíduos Industriais/análise
5.
Magy Seb ; 66(3): 161-5, 2013 Jun.
Artigo em Húngaro | MEDLINE | ID: mdl-23782604

RESUMO

The hemorheological parameters, such as whole blood viscosity, plasma viscosity, hematocrit, fibrinogen concentration as well as the micro-rheological properties of red blood cells (red blood cell deformability and aggregation) play an important role in tissue perfusion. The alternating hemorheological parameters, which are also inter-related, have important effects in determining hemodynamical properties, as well. The altered hemorheological status has a direct effect on endothelial function by changing shear force profile on the endothelial wall, and impairment of red blood cell deformability and aggregation (presence of rigid red blood cell, and enhanced red blood cell aggregation) slows down microcirculation with disturbing capillary perfusion. In experimental surgery vascular clamping and release cause ischemia-reperfusion, which affect red blood cells in many ways: changes pH level, leads to free-radical release, changes osmolarity and lactate and NO concentrations as well as it causes mechanical trauma. Understanding of these pathophysiological processes and determining the extent of reversible-irreversible changes may help to delineate underlying causes in tissue perfusion and microcirculation better, and develop prophylactic and therapeutic possibilities. The challenges of experimental surgery also include the questions of comparability in different measurement methods, and understanding of interspecies-differences of experimental/laboratory animal models in order to increase the relevance of results in terms of applicability for the original, clinical question.


Assuntos
Hemorreologia , Animais , Viscosidade Sanguínea , Endotélio Vascular/fisiopatologia , Agregação Eritrocítica , Deformação Eritrocítica , Fibrinogênio/metabolismo , Hematócrito , Microcirculação , Modelos Animais , Traumatismo por Reperfusão/etiologia , Especificidade da Espécie , Procedimentos Cirúrgicos Vasculares
6.
Geburtshilfe Frauenheilkd ; 83(9): 1127-1137, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37942358

RESUMO

Introduction: While premenopausal patients with HR+ HER2- early breast cancer are treated with tamoxifen +/- ovarian suppression with a GnRH analog or an aromatase inhibitor (AI) + GnRH, the majority of postmenopausal women receive an AI due to its higher efficacy compared to tamoxifen. As the introduction of CDK4/6 inhibitors into the treatment of early-stage breast cancer with a higher risk of recurrence will probably result in a shift in the endocrine treatment landscape, the question is what treatment did potential candidates for CDK4/6 inhibitors in Germany receive before CDK4/6 inhibitors were available. Patients and Methods: As part of a retrospective multicenter analysis, anonymized data were collected of patients with HR+ HER2- early-stage breast cancer who received endocrine therapy in the period between 10/2021 and 03/2022. Potential candidates for CDK4/6 inhibitor treatment were classified into different risk cohorts using the inclusion criteria of the NATALEE and monarchE trials. Results: The data of 238 patients from 29 different centers were analyzed. While 20.6% of patients met the monarchE criteria, the subgroup which met the NATALEE inclusion criteria consisted of 46.2% of patients. 53.8% of patients did not meet the inclusion criteria for either the NATALEE or the monarchE trial. More than half of the patients did not receive chemotherapy. 28.6% of patients in the whole cohort were premenopausal. 67.6% of premenopausal women received neo-/adjuvant chemotherapy. 61.8% of premenopausal patients received tamoxifen as adjuvant endocrine therapy, 19.1% received an AI + GnRH and 10.3% were treated with tamoxifen + GnRH. Conclusion: Despite the high percentage of premenopausal patients who received aggressive treatment in the form of chemotherapy, only one third of premenopausal patients received GnRH in addition to their standard endocrine therapy. Studies carried out at a later point in time and registry studies will be necessary to see how the endocrine therapy landscape in Germany has changed following the introduction of CDK4/6 inhibitors.

7.
J Cell Biochem ; 112(6): 1630-42, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21328613

RESUMO

As the primary mediators of lipophilic and steroid hormone signalling, the family of nuclear receptors (NRs) plays a central role in the regulation of metazoan development. Lipophilic hormones are also thought to be important players in the molecular interaction between larval cestodes and their hosts but no member of the NR family has yet been characterised in this group of parasites. In this work, we provide for the first time evidence for the presence of NRs in cestodes of the genus Echinococcus. By bioinformatic analyses, we identified a set of 17 NRs in the genomes of E. multilocularis and E. granulosus which broadly overlapped with the set of NRs that is expressed by schistosomes, but also contained several members that are unique to cestodes. One of these receptors, EmNHR1, displayed structural homologies to the DAF-12/HR-96 subfamily of NRs that regulates cholesterol homeostasis and longevity in metazoans. By RT-PCR analyses, we demonstrate that the EmNHR1 encoding gene is expressed in all Echinococcus larval stages that are involved in the infection of the intermediate host. By yeast two-hybrid analyses, we further demonstrate cross-communication between EmNHR1 and TGF-ß signalling pathways in Echinococcus and that mammalian serum contains a ligand that induces homodimerisation of the EmNHR1 ligand-binding domain. EmNHR1 could thus play an important role in hormonal host-parasite cross-communication mechanisms during an infection. On the basis of our results, further investigations into the role of NR signalling in cestode development and host-parasite interaction will be greatly facilitated.


Assuntos
Echinococcus multilocularis/metabolismo , Proteínas de Helminto/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Biologia Computacional , Echinococcus multilocularis/genética , Echinococcus multilocularis/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Helminto/genética , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Ligação Proteica , Receptores Citoplasmáticos e Nucleares/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Clin Hemorheol Microcirc ; 79(4): 557-565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34420941

RESUMO

BACKGROUND: Ischemia-reperfusion (I/R) may worsen blood rheology that has been demonstrated by clinical and experimental data. It is also known that anti-inflammatory agents and preconditioning methods may reduce I/R injury. OBJECTIVE: We aimed to analyze hemorheological alterations in elective knee operations and the effects of intraoperative nonsteroidal anti-inflammatory drug (NSAID) administration and application of ischemic preconditioning. METHODS: Hemorheological variables of 17 patients with total knee replacement or anterior crucial ligament replacement were analyzed. The ischemic (tourniquet) time was 92±15 minutes. Seven patients did not receive NSAID (Control group), 5 patients got i.v. sodium-diclophenac 10 minutes before and 6 hours after reperfusion. Five patients had ischemic preconditioning (3×15 minutes). Blood samples were collected before the ischemia, 10 minutes after reperfusion, on the 1st and 2nd p.o. day. RESULTS: Whole blood viscosity didn't show notable inter-group differences, except for a slight decrease in the preconditioning group. RBC deformability decreased, erythrocyte aggregation enhanced by the 1st and 2nd p.o. days in Control group. In NSAID and preconditioning groups the changes were moderate, aggregation values significantly lowered compared to the Control group. CONCLUSION: Intraoperatively administered diclophenac or ischemic preconditioning could moderate the deterioration in micro-rheological parameters caused by I/R in patients.


Assuntos
Precondicionamento Isquêmico , Traumatismo por Reperfusão , Diclofenaco , Humanos , Extremidade Inferior , Dados Preliminares , Traumatismo por Reperfusão/prevenção & controle , Reologia
9.
Diagn Microbiol Infect Dis ; 101(1): 115420, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34091111

RESUMO

Between 2014 and 2017, 6,662 Enterobacterales and 1,953 P. aeruginosa isolates were collected by 19 centers in four central European countries and Israel. A further 2,585 Enterobacterales and 707 P. aeruginosa isolates were collected in 2018 by 28 centers in seven European countries and Israel as part of the Antimicrobial Testing Leadership and Surveillance (ATLAS) study. A central laboratory performed antimicrobial susceptibility testing using broth microdilution panels according to Clinical Laboratory Standards Institute (CLSI) guidelines. Susceptibility rates among Enterobacterales were highest to ceftazidime-avibactam (≥98.5%), colistin (≥97.3%), and meropenem (≥95.8%). Ceftazidime-resistant and multidrug-resistant (MDR) Enterobacterales subsets were highly susceptible to ceftazidime-avibactam (≥94.9%) and colistin (≥94.7%). Susceptibility rates to colistin among all P. aeruginosa were ≥97.4% and were ≥96.3% among ceftazidime-resistant and MDR subsets. Susceptibility rates to ceftazidime-avibactam were 91.9% (2014-2017), 86.3% (2018) and, in common with comparator agents, were lower among ceftazidime-resistant (≥51.7%) and MDR isolates (≥57.1%).


Assuntos
Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Ceftazidima/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Combinação de Medicamentos , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Europa (Continente) , Humanos , Israel , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Inibidores de beta-Lactamases/farmacologia
10.
Microsurgery ; 30(4): 321-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19790184

RESUMO

The aim of this study was to investigate intestinal ischemia-reperfusion and its local and systemic hemorheological relations in the rat. Ten anaesthetized female CD outbred rats were equally divided into 2 experimental groups. (1) Ischemia-reperfusion (I/R): the superior mesenterial artery was clipped for 30 minutes. After removing the clip, 60 minutes of the reperfusion was observed before extermination. Blood samples were taken from the caudal caval vein and from the portal vein before ischemia, 1 minute before and after clip removal, and at the 15th, 30th, and 60th minutes of the reperfusion. (2) Sham operation: median laparotomy and blood sampling were done according to the timing as in I/R group. Hematological parameters, red blood cell aggregation, and deformability were determined. Leukocyte count and mean volume of erythrocytes increased slightly but continuously in portal venous samples during the reperfusion period. Red blood cell aggregation values were higher in portal blood by the end of ischemia, and then became elevated further comparing to the caval venous blood. Both in caval and portal venous samples of I/R group red blood cell deformability significantly worsened during the experimental period compared to its base and Sham group. In portal blood red blood cell deformability was impaired more than in caval vein samples. Histology showed denuded villi, dilated capillaries, and the inflammatory cells were increased after a 30 minutes ischemia. In conclusion, intestinal ischemia-reperfusion causes changes in erythrocyte deformability and aggregation, showing local versus systemic differences in venous blood during the first hour of reperfusion.


Assuntos
Hemorreologia/fisiologia , Intestinos/irrigação sanguínea , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Análise de Variância , Animais , Biópsia por Agulha , Modelos Animais de Doenças , Agregação Eritrocítica , Feminino , Imuno-Histoquímica , Intestinos/patologia , Contagem de Leucócitos , Microcirculação/fisiologia , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344 , Fluxo Sanguíneo Regional , Traumatismo por Reperfusão/sangue , Medição de Risco , Estatísticas não Paramétricas
11.
Microsurgery ; 30(8): 649-56, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20853334

RESUMO

Artificial femoral arterio-venous (AV) shunts are widely used in rodent models for studying shunt maturation and to optimize various surgical techniques. However, little is known about complex circulatory, microcirculatory, and hemorheological effects of end-to-side saphenous AV shunts. We aimed to study these parameters in mature AV shunts. Studying these questions in CD rats, end-to-side anastomoses were made between the left saphenous artery and vein. On the right-side the nonoperated saphenous vessels served as own control. Furthermore healthy control animals were also investigated. On the 8th to 12th postoperative week microcirculatory and blood flow measurements were performed and blood samples were taken both from the shunt's arterial and venous limbs and from the nonoperated side vessels. Hematological parameters, erythrocyte aggregation, and deformability were determined. The entire shunt and the control vessels were removed for histological examinations. The skin microcirculation on shunt side slightly increased on thigh and decreased on paws versus the nonoperated side. Blood flow measurements made directly on the vessels showed that arterial to venous blood flow rate ratio was 1.59 ± 0.29 on nonoperated side and 1.2 ± 0.13 on the shunt side, and 1.49 ± 0.05 in control animals. Erythrocyte aggregation and deformability worsened on the shunt side. Histologically increased number of smooth muscle elements and connective tissue were found in venous limb of the shunts. The artificial AV shunt between the saphenous artery and vein seems to be a suitable model for further functional-morphological and hemorheological examinations of hemodialysis in various states and diseases.


Assuntos
Derivação Arteriovenosa Cirúrgica , Animais , Animais não Endogâmicos , Agregação Eritrocítica , Deformação Eritrocítica , Hemorreologia , Membro Posterior/irrigação sanguínea , Microcirculação , Microcirurgia , Ratos , Fluxo Sanguíneo Regional , Veia Safena , Pele/irrigação sanguínea
13.
Clin Hemorheol Microcirc ; 66(1): 83-96, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28128749

RESUMO

BACKGROUND: Partial or subtotal spleen resection or spleen autotransplantation can partly preserve/restore the splenic filtration function, as previous studies demonstrated. OBJECTIVE: For better evaluation and follow-up of the various spleen-preserving operative techniques' effectiveness versus splenectomy, a composite methodological approach was applied in a canine experimental model. METHODS: Beagle dogs were subjected to control (n = 6), splenectomy (SE, n = 4), partial and subtotal spleen resection (n = 4/each) or spleen autotransplantation groups (AU, Furka's spleen-chip method, n = 8). The follow-up period was 18 postoperative (p.o.) months. Erythrocyte deformability was determined in parallel by bulk filtrometry (Carat FT-1 filtrometer), slit-flow ektacytometry (RheoScan D-200) and rotational ektacytometry (LoRRca MaxSis Osmoscan). RESULTS: By filtrometry, relative cell transit time increased in the SE group (mostly in animal Nr. SE-3), showing the highest values on the 3rd, 9th and in 18th p.o. months. Elongation index values decreased in this group (both by slit-flow and rotational ektacytometers). In general, AU and two resection groups' values were lower versus control and higher than in SE. CONCLUSIONS: Forasmuch in the circulation both elongation by shear stress and filtration occur, these various erythrocyte deformability testing methods together may describe better the alterations. Considering the possible complications related to functional asplenic-hyposplenic conditions, individual analysis of cases is highly important.


Assuntos
Deformação Eritrocítica/fisiologia , Baço/cirurgia , Esplenectomia/métodos , Transplante Autólogo/métodos , Animais , Modelos Animais de Doenças , Cães , Seguimentos , Humanos , Período Pós-Operatório , Baço/patologia
14.
Clin Hemorheol Microcirc ; 62(3): 215-27, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26444597

RESUMO

Laboratory investigations often require centrifugation of blood samples for various erythrocyte tests. Although there is a lack of data about the effect of centrifugation at various g force levels on erythrocyte rheological properties. We aimed to investigate the effect of a 10-minute centrifugation at 500, 1000 or 1500 g at 15°C of rat, dog, pig and human venous (K3-EDTA, 1.5 mg/ml) blood samples. Hematological parameters, erythrocyte deformability, cell membrane stability, osmotic gradient ektacytometry (osmoscan) and erythrocyte aggregation were determined. Hematological and erythrocyte deformability parameters showed interspecies differences, centrifugation caused no significant alterations. Cell membrane stability for human erythrocytes centrifuged at higher g level showed less decrease in deformability. Osmoscan O min parameter showed slight elevation in dog centrifuged aliquots. Erythrocyte aggregation parameters changed unexpectedly. Rat and dog erythrocyte aggregation indices significantly dropped in centrifuged aliquots. Pig erythrocyte aggregation indices increased significantly after centrifugation. Human erythrocyte aggregation was the most stable one among the investigated species. The used centrifugation protocols caused the largest alterations in erythrocyte aggregation in a controversial way among the investigated species. On the other hand, erythrocyte deformability parameters were stable, cell membrane stability and osmoscan data show minor shifts.


Assuntos
Centrifugação , Agregação Eritrocítica , Deformação Eritrocítica , Índices de Eritrócitos , Eritrócitos/citologia , Hemorreologia , Adulto , Animais , Cães , Membrana Eritrocítica/metabolismo , Feminino , Gravitação , Testes Hematológicos/métodos , Humanos , Masculino , Osmose , Ratos , Especificidade da Espécie , Suínos
15.
Clin Hemorheol Microcirc ; 63(4): 381-398, 2016 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26890103

RESUMO

We hypothesized that the results of red blood cell mechanical stability test show interspecies differences. The comparative investigations were performed on blood samples obtained from rats, beagle dogs, pigs and healthy volunteers. Mechanical stress was applied in nine combinations: 30, 60 or 100 Pa shear stress for 100, 200 or 300 seconds. Generally, rat erythrocytes showed the highest capability of resistance. With the applied combinations of mechanical stress pig erythrocytes were the most sensitive. On human erythrocytes 60 Pa for 200 s was the minimum combination to result significant deformability deterioration. By increasing the magnitude and duration of the applied mechanical stress we experienced escalating deformability impairment in all species. 100 Pa shear stress for 300 seconds on human erythrocytes showed the largest deformability impairment. The mechanical stability test results were also dependent on osmolality. At hypoosmolar range (200 mOsmol/kg) the mechanical stress improved EI data mostly in rat and porcine blood. At higher osmolality (500 mOsmol/kg), the test did not show detectable difference, while in 250-300 mOsmol/kg range the differences were well observable. In summary, erythrocytes' capability of resistance against mechanical stress shows interspecies differences depending on the magnitude and duration of the applied stress, and on the osmolality.


Assuntos
Deformação Eritrocítica/fisiologia , Adulto , Animais , Cães , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Concentração Osmolar , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Suínos
16.
Asian J Androl ; 18(3): 462-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26178399

RESUMO

Testicular torsion may lead to serious ischemia, and the viability depends on the duration of torsion and the effect of ischemia-reperfusion. Testicular decompression and tunica vaginalis flap application technique were introduced in 2008 by Kutikov et al. We aimed to examine the impact of this method on the testicular microcirculation and hemorheological parameters in a rat model. Six adult rats underwent bilateral scrotal exploration. Intravaginal torsion of the testis was created by 720° rotation on both sides for 2 h. After detorsion, the right testes underwent tunica albuginea incision and tunica vaginalis flap application. Testicular microcirculation was monitored and hematological parameters, erythrocyte deformability, and aggregation were determined. Measurements were performed before and after torsion, directly after detorsion, on the 1 st -2 nd and 8 th postoperative day. After the last sampling, testicles were removed to determine their volume for histological examinations. The microcirculatory parameters demonstrated slight differences between testicles. Apical zone of the left (nondecompressed) testicles had elevated compared to the middle zone (P < 0.05). On the 2 nd and 8 th day, the microcirculation of the testes normalized but not equally. The erythrocyte aggregation and deformability decreased by the 8 th day. Both testicles underwent atrophy and epithelial necrosis, but the volume of the decompressed ones was lower (1.07 ± 0.08 vs 1.25 ± 0.31). Histologically, there was no significant difference in epithelial damage score between decompressed and nondecompressed testes. In conclusion, 2-h ischemia led to alteration in testicular microcirculation, reduction in volume, changes in hemorheological parameters and serious epithelial necrosis both in decompressed and nondecompressed testicles without remarkable differences.


Assuntos
Isquemia/patologia , Microcirculação , Torção do Cordão Espermático/patologia , Testículo/patologia , Animais , Atrofia , Descompressão Cirúrgica , Índices de Eritrócitos , Masculino , Necrose , Tamanho do Órgão , Ratos , Torção do Cordão Espermático/cirurgia , Retalhos Cirúrgicos , Testículo/irrigação sanguínea
17.
Magy Seb ; 58(2): 144-7, 2005 Apr.
Artigo em Húngaro | MEDLINE | ID: mdl-16018285

RESUMO

Rheological properties of the blood are determined by several factors and if they change it may be diagnostic for many diseases. It is well-known that during ischemia and reperfusion different free-radical liberating pathways are inducted besides the local physical and metabolical changes. These processes may harm red blood cells by increasing their rigidity and impairing their deformability. In ischemia-reperfusion models measurements of erythrocyte deformability is important. Characteristic alterations were observed in both rat and dog hind limb ischemia-reperfusion with vascular clamping on femoral vessels for 1 or 3 hours. Erythrocyte deformability was significantly impaired on the postoperative 1st-3rd days. The acute limb ischemia-reperfusion experimental models seem suitable for further in vivo rheological studies.


Assuntos
Deformação Eritrocítica , Extremidades/irrigação sanguínea , Hemorreologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Modelos Animais de Doenças , Cães , Ratos , Fatores de Tempo
18.
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
19.
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
20.
Acta Cir Bras ; 30(8): 551-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26352335

RESUMO

PURPOSE: To examine how the ischemia-reperfusion injury of latissimus dorsi-cutaneous maximus (LDCM) musculocutaneous flap affects the microcirculatory (flap's skin surface) and hemorheological parameters, and whether an intraoperative deterioration would predictively suggest flap failure in the postoperative period. METHODS: Ten healthy male rats were subjected to the study. In Group I the left flap was sutured back after 2-hour, while the contralateral side was right after its elevation. In Group II the same technique was applied, but the pedicle of the left flap was atraumatically clamped for 2-hour. The contralateral side was left intact. On the flap skin surface laser Doppler tissue flowmetry measurements were done before and after and during the protocols applied in the groups. Microcirculatory and hemorheological examinations were done postoperatively. RESULTS: The microcirculatory parameters significantly decreased during immobilization and ischemia. Afterwards, all the regions showed normalization. In the retrospective analysis there was a prominent difference between the microcirculatory parameters of necrotic and survived flap during the early postoperative days (1-3) in Group II. Erythrocyte aggregation and deformability showed only slight differences. CONCLUSIONS: Two-hour ischemia and reperfusion caused deterioration in latissimus dorsi-cutaneous maximus flap microcirculation. Predicting the possible postoperative complication, the intraoperative laser Doppler measurement can be informative.


Assuntos
Hemorreologia/fisiologia , Microcirculação/fisiologia , Retalho Miocutâneo/irrigação sanguínea , Traumatismo por Reperfusão/fisiopatologia , Pele/irrigação sanguínea , Músculos Superficiais do Dorso/irrigação sanguínea , Animais , Procedimentos Cirúrgicos Dermatológicos , Modelos Animais de Doenças , Período Intraoperatório , Fluxometria por Laser-Doppler , Masculino , Retalho Miocutâneo/patologia , Período Pós-Operatório , Distribuição Aleatória , Ratos , Pele/patologia , Transplante de Pele/métodos , Músculos Superficiais do Dorso/patologia , Fatores de Tempo
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