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1.
Am J Transplant ; 17(7): 1802-1812, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28117941

RESUMO

Heart transplantation is the therapy of choice for end-stage heart failure. However, hemodynamic instability, which has been demonstrated in brain-dead donors (BDD), could also affect the posttransplant graft function. We tested the hypothesis that treatment of the BDD with the dopamine derivate n-octanoyl-dopamine (NOD) improves donor cardiac and graft function after transplantation. Donor rats were given a continuous intravenous infusion of either NOD (0.882 mg/kg/h, BDD+NOD, n = 6) or a physiological saline vehicle (BDD, n = 9) for 5 h after the induction of brain death by inflation of a subdural balloon catheter. Controls were sham-operated (n = 9). In BDD, decreased left-ventricular contractility (ejection fraction; maximum rate of rise of left-ventricular pressure; preload recruitable stroke work), relaxation (maximum rate of fall of left-ventricular pressure; Tau), and increased end-diastolic stiffness were significantly improved after the NOD treatment. Following the transplantation, the NOD-treatment of BDD improved impaired systolic function and ventricular relaxation. Additionally, after transplantation increased interleukin-6, tumor necrosis factor TNF-α, NF-kappaB-p65, and nuclear factor (NF)-kappaB-p105 gene expression, and increased caspase-3, TNF-α and NF-kappaB protein expression could be significantly downregulated by the NOD treatment compared to BDD. BDD postconditioning with NOD through downregulation of the pro-apoptotic factor caspase-3, pro-inflammatory cytokines, and NF-kappaB may protect the heart against the myocardial injuries associated with brain death and ischemia/reperfusion.


Assuntos
Morte Encefálica , Dopamina/análogos & derivados , Transplante de Coração/métodos , Precondicionamento Isquêmico , Traumatismo por Reperfusão/prevenção & controle , Doadores de Tecidos , Função Ventricular Esquerda/fisiologia , Animais , Caspase 3/metabolismo , Dopamina/farmacologia , Interleucina-6/metabolismo , Masculino , NF-kappa B/metabolismo , Ratos , Ratos Endogâmicos Lew , Fator de Necrose Tumoral alfa/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos
2.
Cryo Letters ; 32(2): 148-57, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21766144

RESUMO

Fourier transform infrared spectroscopy (FTIR) and cryomicroscopy were used to study the effects of dimethyl sulfoxide and ethylene glycol on cell pellets of human pulmonary microvascular endothelial cells during freezing from 4 degree C to -60 degree C at 1 degree C per min. FTIR analysis showed that membranes undergo a phase change in the presence of cryoprotective agents (CPAs) which was not observed in the absence of CPAs. Cryomicroscopy revealed the formation of intracellular ice and concomitant cell volume changes. Intracellular ice was detected in the majority of the cells both in the presence and absence of CPAs. Membrane phase changes were found to be most pronounced at intermediate concentrations of cryoprotective agents; for dimethyl sulfoxide at around 1 M and for ethylene glycol at around 1.5 M. At those concentrations cell survival after thawing exhibited a maximum. The results indicate that CPAs promote rather than prevent cell dehydration during freezing.


Assuntos
Membrana Celular/metabolismo , Criopreservação/métodos , Células Endoteliais/fisiologia , Membrana Celular/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Células Endoteliais/citologia , Etilenoglicol/farmacologia , Congelamento , Humanos , Gelo/análise , Pulmão/citologia , Pulmão/fisiologia , Microscopia , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Reproduction ; 127(5): 547-56, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15129010

RESUMO

Sperm cryopreservation and artificial insemination are important management tools for giant panda breeding and the preservation of extant genetic diversity. This study examined the influence of freeze-thawing on sperm function, specifically capacitation. Sperm from nine giant pandas were assessed before and after rapid (- 40 and - 100 degrees C/min) cryopreservation by incubation in HEPES-buffered Ham's F10 medium with and without the capacitation accelerators, 3-isobutyl-1-methylxanthine (IBMX) and dibutyryl cyclic AMP (dbcAMP). At 0, 3 and 6 h of exposure, aliquots were assessed for sperm motility traits and capacitation, defined as the proportion of sperm with intact acrosomes following exposure to solubilised zonae pellucidae (ursid or felid) or calcium ionophore subtracted from the proportion of sperm with intact acrosomes before exposure. Although mean+/-S.E.M. sperm motility post-thaw (56.1 +/- 3.9% at 0 h) was less (P < 0.05) than pre-freeze (71.7 +/- 6.0%), there was no difference (P > 0.05) in the proportion of acrosome-intact sperm (fresh, 93.0 +/- 1.7% versus cryopreserved-thawed, 81.7 +/- 4.7% at 0 h). Incidence of capacitation was greater (P < 0.05) in fresh sperm incubated with capacitation accelerators IBMX and dbcAMP (9 h: 50.9 +/- 1.1) compared with fresh sperm incubated without accelerators (9 h: 41.2 +/- 1.1%). Frozen-thawed sperm preincubated without accelerators underwent capacitation (49.6 +/- 1.1%) to a greater extent (P < 0.05) compared with these fresh counterparts. Thawed samples with (9 h: 45.9 +/- 1.4%) and without accelerators (9 h: 41.2 +/- 1.1%) did not differ (P > 0.05) during the 9-h incubation. We conclude that giant panda spermatozoa (1) undergo capacitation in vitro with or without chemical accelerators and (2) withstand a rapid cryopreservation protocol, including retaining normal acrosomal integrity and functional capacitation ability.


Assuntos
Acrossomo/fisiologia , Criopreservação/veterinária , Preservação do Sêmen/veterinária , Capacitação Espermática/fisiologia , Ursidae/fisiologia , 1-Metil-3-Isobutilxantina , Animais , Bucladesina , Cálcio/metabolismo , Células Cultivadas , Criopreservação/métodos , Meios de Cultura , Feminino , Ionóforos/farmacologia , Masculino , Preservação do Sêmen/métodos , Zona Pelúcida/metabolismo
4.
Theriogenology ; 56(3): 399-413, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11516120

RESUMO

Sperm capacitation was examined in the endangered Eld's deer (Cervus eldi thamin). Sperm motility and viability (percentage of sperm cells with intact membranes) were assessed in vitro over time after attempting to induce capacitation in TALP alone and TALP supplemented with calcium (10 mM CaCl2), dibutyryl cAMP (1 mM dbcAMP), or fetal calf serum (20% FCS). Sperm aliquots were evaluated at 0, 3, 6, 9, and 12 h for motility, viability, and ability to acrosome react after exposure to calcium ionophore (A23187, CI; 10 microM) or lysophosphatidylcholine (LC; 100 microg/mL). Fresh sperm aliquots in TALP + 10 mM CaCl2 exposed to CI had fewer (P < 0.05) intact acrosomes than the TALP control (TALP alone) or dbcAMP and FCS treatments after 9 h. Mean (+/- SEM) percentage of intact acrosomes of spermatozoa incubated in medium with increased CaCl2 declined (P < 0.05) from 80.2 +/- 2.6% (0 h) to 49.7 +/- 7.3% after prolonged incubation (9 h). The proportion of capacitated fresh spermatozoa was not influenced by LC treatment. Capacitation was not induced (P > 0.05) by any of the presumptive sperm capacitators after freeze-thawing. Likewise, neither CI nor LC induced the acrosome reaction (AR) in these spermatozoa, suggesting that the freeze-thawing process may have caused membrane damage. Results revealed that the supplementation of medium with CaCl2 evokes capacitation in some spermatozoa. However, Eld's deer spermatozoa appear remarkably resistant to conventional stimulators of capacitation and the AR.


Assuntos
Cervos/fisiologia , Capacitação Espermática/fisiologia , Espermatozoides/fisiologia , Reação Acrossômica/efeitos dos fármacos , Reação Acrossômica/fisiologia , Animais , Bucladesina/farmacologia , Calcimicina/farmacologia , Cloreto de Cálcio/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Conservação dos Recursos Naturais , Criopreservação/veterinária , Sangue Fetal/fisiologia , Ionóforos/farmacologia , Lisofosfatidilcolinas/farmacologia , Masculino , Preservação do Sêmen/veterinária , Capacitação Espermática/efeitos dos fármacos , Motilidade dos Espermatozoides/fisiologia
5.
J Reprod Fertil ; 115(1): 79-86, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10341725

RESUMO

The tammar wallaby, Macropus eugenii, has a ruminant-like digestive system which may make a significant concentration of amino acids and fatty acids available to the blastocyst via uterine fluids. Fluorescent and radioisotope analyses were performed to determine the rate of glutamine and palmitate use by blastocysts recovered on day 0, 3, 4, 5 and 10 after reactivation induced by removal of pouch young (RPY). Between day 0 and 4 glutamine uptake increased from 15.6 +/- 6.6 to 36.1 +/- 2.7 pmol per embryo h-1 (P < 0.01) and ammonium production increased from 8.2 +/- 4.3 to 26.6 +/- 3.0 pmol per embryo h-1 (P < 0.01). Glutamine oxidation did not increase until day 10 after RPY (P < 0.01), but the percentage of glutamine oxidized increased from 4.5 +/- 3.1% during diapause to 31.2 +/- 12.6% (P < 0.01) by day 5 after RPY and increased further to 51.0 +/- 15.8% (P < 0.01) by day 10 after RPY. Palmitate oxidation also increased from 0.3 +/- 0.1 by day 0 blastocysts to 3.8 +/- 1.7 pmol per embryo h-1 (P < 0.01) by day 4 blastocysts. This increase provides a greater potential for ATP production, possibly to supply increased demand due to the coincident resumption of mitoses. The ATP:ADP ratio within blastocysts had reduced by the time of the first measurement at day 3 (0.5 +/- 0.2 pmol per embryo h-1; P < 0.01) compared with day 0 blastocysts (1.4 +/- 0.3 pmol per embryo h-1). It is likely that metabolism of amino acids and fatty acids contributes to the energy supply during reactivation of tammar wallaby blastocysts after embryonic diapause.


Assuntos
Blastocisto/metabolismo , Implantação Tardia do Embrião/fisiologia , Glutamina/metabolismo , Macropodidae/metabolismo , Palmitatos/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Análise de Variância , Animais , Blastocisto/citologia , Endométrio/metabolismo , Feminino , Índice Mitótico , Gravidez , Fatores de Tempo
6.
Zentralbl Chir ; 124 Suppl 4: 23-7, 1999.
Artigo em Alemão | MEDLINE | ID: mdl-10670112

RESUMO

Postoperative infections are a dreaded complication in pulmonal surgery. Besides the optimal preparation of the patients and careful operative technique, perioperative antibiotic prophylaxis represents an important factor in avoiding infectious consequences. Owing particularly to the high proportion of patients with malignant, consumptious illnesses in thorax surgery, immune deficiencies must be reckoned with in this group of patients. The spectrum of germs to be expected within the framework of pulmonal surgery determines to some extent which antibiotic shall be used. We have investigated the efficacy of a standardized antibiotic prophylaxis using cefotaxime (Claforan) in 200 pulmonal patients. Pleural empyema is a rare, but nonetheless important infectious illness, as a consequence of pulmonal operations, or also following pneumonia. Whilst the early stages of an empyema can often be successfully treated using only drainage treatment, chronic empyema usually requires a thoracotomy with empyema dissection and excortication, as well as subsequent irrigation-suction drainage treatment. In spite of specific surgical sanitation and irrigation-suction drainage treatment, therapy is often complicated by persistent germs in the thoracic cavity. Instillation therapy with taurolidine can lead to faster healing of the infection in such cases. Purulent mediastinitis is an extremely rare illness, but dreaded owing to its high mortality. The causes of the illness lie in injuries of the trachea, of the bronchial tubes, and of the oesophagus. With the introduction of medial sternotomy as operative entry, mediastinitis as a postoperative complication has increased noticeably in frequency. Mediastinitis occurs as a descending infection as a consequence of odontogenic affections. Owing to frequently late diagnosis, infection is usually advanced, so that simple drainage treatment of the mediastinum no longer suffices in many cases. We introduce our concept of treatment using our own patient collective.


Assuntos
Antibacterianos/uso terapêutico , Cefotaxima/uso terapêutico , Cefalosporinas/uso terapêutico , Pneumopatias/cirurgia , Pneumonectomia/efeitos adversos , Infecção da Ferida Cirúrgica/prevenção & controle , Cefalosporinas/farmacologia , Humanos , Complicações Pós-Operatórias , Infecção da Ferida Cirúrgica/tratamento farmacológico
7.
Biol Reprod ; 58(6): 1425-31, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9623601

RESUMO

Metabolic reactivation of the tammar blastocyst appears to be characterized by a change in the pathway of glucose metabolism rather than an absolute increase in substrate uptake. The switch in type of metabolism used was examined to gain information on the timing and physiology of blastocyst reactivation. Fluorescent and radioisotope techniques were used sequentially to determine the activity of pathways of glucose metabolism by individual wallaby blastocysts during diapause and 3, 4, 5, 6, 7, 8, and 10 days after removal of pouch young (RPY). Maternal endometrial and luteal cell metabolism and circulating hormone levels were measured and correlated with blastocyst activity. Observed differences between rates of blastocyst reactivation could be explained by variation in the maternal response between animals. While blastocysts recovered 4 days after RPY oxidized more glucose compared with Day 0 blastocysts (p < 0.05), rates of glycolysis did not change until Day 10. Blastocysts recovered between 4 and 10 days after RPY oxidized a significantly greater percentage of the glucose taken up (p < 0.01). The reduced ATP:ADP ratio within blastocysts recovered 3 days after RPY (p < 0.05) indicates that conditions are suitable for blastocysts to undergo a metabolic switch from glycolytic to oxidative metabolism of glucose on Day 4 after RPY. The increased oxidation results in greater ATP production, which plausibly fuels the increased energy requirements of wallaby blastocysts during the early stages of reactivation.


Assuntos
Blastocisto/fisiologia , Glucose/metabolismo , Macropodidae/embriologia , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Corpo Lúteo/metabolismo , Endométrio/metabolismo , Feminino , Oxirredução , Gravidez , Progesterona/sangue , Fatores de Tempo
8.
J Exp Zool ; 276(2): 132-7, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8900076

RESUMO

The mouse, Mus musculus, can maintain blastocysts in embryonic diapause in the uterus while suckling young. This study used microfluorimetry to simultaneously examine glucose and pyruvate uptake by quiescent blastocysts, and at four hourly intervals after administration of the reactivating stimulus, oestradiol-17 beta. Following the non-invasive analysis of energy metabolism, blastocysts were incubated in colcemid (0.2 mg/ml), and mitotic activity determined. Mitoses and cell numbers in reactivated embryos increased significantly within 8 and 12 hours, respectively, after oestradiol-17 beta administration, compared to those of diapause (control) blastocysts (0.5 +/- 0.1 vs. 0.22 +/- 0.03 mitoses/embryo; P < 0.05, and 141.8 +/- 1.5 vs. 133.8 +/- 2.4 cells/ embryo; P < 0.05). Similarly, pyruvate uptake by reactivating blastocysts (9.3 +/- 1.1) was significantly higher than controls (5.8 +/- 0.8 pmol/embryo/hour; P < 0.05), within 4 hours of oestradiol-17 beta, but by 16 hours after oestradiol-17 beta administration, pyruvate uptake by reactivating blastocysts was no longer significantly different from the delayed controls. In contrast, significant differences in glucose uptake between the reactivated and control groups were not evident until 16 hours after oestradiol-17 beta (reactivating, 14.9 +/- 1.5; control, 10.6 +/- 1.7 pmol/embryo/hour; P < 0.05). These results demonstrate that pyruvate rather than glucose could supply the additional energy required during the first 12 hours of reactivation in the mouse, but from 16 hours after injection of the reactivating stimulus oestradiol-17 beta, glucose is the predominant energy source.


Assuntos
Blastocisto/metabolismo , Glucose/metabolismo , Animais , Blastocisto/citologia , Contagem de Células/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Implantação do Embrião/efeitos dos fármacos , Implantação do Embrião/fisiologia , Estradiol/farmacologia , Feminino , Masculino , Camundongos , Microscopia de Fluorescência , Gravidez , Ácido Pirúvico/metabolismo
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