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1.
Cancer Gene Ther ; 24(2): 45-47, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28106046

RESUMO

We previously described the development of a highly-invasive, triple-negative breast cancer (TNBC) variant using serial orthotopic implantation of MDA-MB-231 human breast cancer in nude mice. The isolated variant is highly invasive in the mammary gland and metastasized to lymph nodes in 10 of 12 mice compared with 2 of 12 of the parental cell line. OBP-401 is a telomerase-dependent cancer-specific, green fluorescent protein (GFP)-expressing adenovirus. OBP-401 was used to infect parental MDA-MB-231P cells and high-metastatic MDA-MB-231H and MDA-MB-231HLN isolated from a lymph node metastasis and MDA-MB-231HLM isolated from a lung metastasis. Time-course imaging showed that OBP-401 labeled MDA-MB-231HP, MDA-MB-231HLN, and MDA-MB-231HLM cells more brightly than MDA-MB-231 parental cells. OBP-401 killed MDA-MB-231H, MDA-MB-231HLN, and MDA-MB-231HLM cells more efficiently than MDA-MB-231P parental cells. These results indicate that OBP-401 could infect, label and then kill high-metastatic MDA-MB-231 more efficiently than low-metastatic MDA-MB-231.


Assuntos
Adenoviridae/genética , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Vírus Oncolíticos/genética , Telomerase/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Expressão Gênica , Genes Reporter , Humanos , Camundongos , Metástase Neoplásica , Neoplasias de Mama Triplo Negativas/terapia
2.
Am J Transplant ; 16(2): 625-33, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26517570

RESUMO

We investigated the impact of polymorphisms in host innate immunoregulatory genes on the development of infectious complications after liver transplantation (LT). The single-nucleotide polymorphisms (SNPs) of C1QA [276A/G], FCGR2A [131H/R], and FCGR3A [158F/V], genes encoding the Fc gamma receptor (FcγR), were analyzed in 89 living donor LT recipients in relation to the occurrences of postoperative infectious complications within 30 days after LT. Consistent with a lower affinity of the isoform encoded by FCGR3A [158F] to both IgG1 and IgG3, a significantly higher incidence of bloodstream infections (BSI) was observed in the FCGR3A [158F/V or F/F] than in the FCGR3A [158V/V] individuals. The combination of FCGR2A and FCGR3A SNPs further stratified the incidence of BSI, regardless of C1QA SNP. The predominant causative pathogen of BSI in the FCGR3A [158F/F or F/V] patients was gram-positive cocci (73.3%), of which one third was methicillin-resistant Staphylococcus aureus. No differences were observed in the incidence of fungal infections or in cytomegalovirus infections with respect to the three gene polymorphisms. Our findings indicate that FcγR SNPs are predisposing factors for BSI and can predict mortality after LT. This study provides a foundation for further prospective studies on a larger scale.


Assuntos
Doenças Transmissíveis/diagnóstico , Rejeição de Enxerto/diagnóstico , Hepatopatias/complicações , Transplante de Fígado/efeitos adversos , Polimorfismo de Nucleotídeo Único/genética , Receptores de IgG/genética , Adulto , Idoso , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/etiologia , Feminino , Seguimentos , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Hepatopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Cuidados Pré-Operatórios , Prognóstico , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
3.
Cancer Gene Ther ; 22(7): 344-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26088297

RESUMO

Precise fluorescence-guided surgery (FGS) for pancreatic cancer has the potential to greatly improve the outcome in this recalcitrant disease. To achieve this goal, we have used genetic reporters to color code cancer and stroma cells in a patient-derived orthotopic xenograft (PDOX) model. The telomerase-dependent green fluorescent protein (GFP)-containing adenovirus OBP-401 was used to label the cancer cells of a pancreatic cancer PDOX. The PDOX was previously grown in a red fluorescent protein (RFP) transgenic mouse that stably labeled the PDOX stroma cells bright red. The color-coded PDOX model enabled FGS to completely resect the pancreatic tumors including stroma. Dual-colored FGS significantly prevented local recurrence, which bright-light surgery or single-color FGS could not. FGS, with color-coded cancer and stroma cells has important potential for improving the outcome of recalcitrant-cancer surgery.


Assuntos
Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Pancreáticas/cirurgia , Cirurgia Assistida por Computador , Animais , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Camundongos Nus , Camundongos Transgênicos , Transplante de Neoplasias , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Proteína Vermelha Fluorescente
4.
Free Radic Res ; 49(3): 269-78, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25511472

RESUMO

Overexpression of cyclooxygenase 2 (COX-2) by stromal fibroblasts plays a critical role in the early stage of carcinogenesis. COX-2 expression is thought to be positively or negatively regulated by inflammatory chemical mediators or tumor suppressors. In this study, the contributions of inducible nitric oxide synthase (iNOS) and p53 to COX-2 expression were examined using mouse embryonic fibroblasts (MEFs) from wild-type, p53-deficient, iNOS-deficient, and p53/iNOS-deficient mice. These MEFs were treated with 1 µg/mL of lipopolysaccharide and 100 IU/mL of interferon gamma for up to 72 h. iNOS and COX-2 expression were analyzed by Western blotting. iNOS was induced earlier (16 h) in p53-deficient MEFs than in wild-type MEFs (48 h). Elevated expression of COX-2 was sustained for a longer duration in the p53-deficient MEFs. In contrast, COX-2 expression was reduced earlier in the iNOS-deficient MEFs. Addition of an exogenous NO donor (0.8 mM of S-nitroso-l-glutathione) to the iNOS-deficient MEFs augmented COX-2 expression. Co-culture with stimulated p53-deficient MEFs promoted cell proliferation of mouse rectal polyploid carcinoma CMT93 cells, but treatment with a COX-2-specific inhibitor counteracted this effect. These results suggest that loss of function of the p53 gene in stromal fibroblasts enhances COX-2 expression by enhancing iNOS expression and the resultant production of NO, contributing to the promotion of tumor growth.


Assuntos
Proliferação de Células , Ciclo-Oxigenase 2/metabolismo , Fibroblastos/metabolismo , Neoplasias Experimentais/metabolismo , Óxido Nítrico/metabolismo , Proteína Supressora de Tumor p53/genética , Animais , Proliferação de Células/genética , Deleção de Genes , Camundongos , Camundongos Knockout , Neoplasias Experimentais/genética , Óxido Nítrico Sintase Tipo II/genética , Transdução de Sinais , Células Estromais/metabolismo
5.
Gene Ther ; 20(1): 112-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22241176

RESUMO

Adenovirus serotype 5 (Ad5) is frequently used as an effective vector for induction of therapeutic transgenes in cancer gene therapy or of tumor cell lysis in oncolytic virotherapy. Ad5 can infect target cells through binding with the coxsackie and adenovirus receptor (CAR). Thus, the infectious ability of Ad5-based vectors depends on the CAR expression level in target cells. There are conventional methods to evaluate the CAR expression level in human target cells, including flow cytometry, western blotting and immunohistochemistry. Here, we show a simple system for detection and assessment of functional CAR expression in human tumor cells, using the green fluorescent protein (GFP)-expressing telomerase-specific replication-competent adenovirus OBP-401. OBP-401 infection induced detectable GFP expression in CAR-expressing tumor cells, but not in CAR-negative tumor cells, nor in CAR-positive normal fibroblasts, 24 h after infection. OBP-401-mediated GFP expression was significantly associated with CAR expression in tumor cells. OBP-401 infection detected tumor cells with low CAR expression more efficiently than conventional methods. OBP-401 also distinguished CAR-positive tumor tissues from CAR-negative tumor and normal tissues in biopsy samples. These results suggest that GFP-expressing telomerase-specific replication-competent adenovirus is a very potent diagnostic tool for assessment of functional CAR expression in tumor cells for Ad5-based antitumor therapy.


Assuntos
Adenoviridae/genética , Telomerase/genética , Replicação Viral/genética , Linhagem Celular Tumoral , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/genética , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Humanos , Vírus Oncolíticos/genética , Telomerase/metabolismo , Transcrição Gênica , Transformação Genética
6.
Transplant Proc ; 44(5): 1446-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22664033

RESUMO

BACKGROUND: When the kidney from a living donor with a double inferior vena cava (IVC) is harvested for renal transplantation, the short length of the renal vein may eventually create a technical problem for graft implantation. Herein, we have reported a rare case of renal vein extension using an autologous renal vein in a living donor with a double IVC. CASE REPORT: A 70-year-old man with end-stage renal disease owing to autosomal-dominant polycystic kidney disease underwent a living donor kidney graft from his wife who had a double IVC. Because of the enlarged kidneys, the patient underwent a bilateral native nephrectomy with concomitant renal transplantation to create space in the pelvis. At nephrectomy, the recipient's renal vein was used to extend the donor renal vein. On the back table, the vein graft was sutured to the donor renal vein, permitting a 3.0-cm extension. RESULTS: The transplantation was performed safely without any complications; the recipient's renal function and blood flow were excellent after the operation. CONCLUSION: This case illustrated that an autologous renal vein graft is a preferable option to extend of short donor renal vein for recipients who require a simultaneous native nephrectomy.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Doadores Vivos , Veias Renais/transplante , Veia Cava Inferior/anormalidades , Idoso , Feminino , Humanos , Imunossupressores/uso terapêutico , Falência Renal Crônica/etiologia , Masculino , Pessoa de Meia-Idade , Nefrectomia , Flebografia/métodos , Rim Policístico Autossômico Dominante/complicações , Veias Renais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Transplante Autólogo , Resultado do Tratamento , Veia Cava Inferior/diagnóstico por imagem
7.
Transplant Proc ; 43(6): 2411-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21839279

RESUMO

A positive crossmatch remains one of the major barriers to successful kidney transplantation. Highly sensitized patients are at greater risk of hyperacute rejection and subsequent graft loss after transplantation. Although recent advances in desensitization therapy allow kidney transplantation in these patients, the success rate is quite low. Herein, we have reported a successful case of positive crossmatch living donor kidney transplantation using a desensitization protocol with an immune monitoring assay. A 42-year-old woman with end-stage renal disease due to IgA nephropathy had been on hemodialysis for 36 months. She showed positive T-cell and B-cell cytotoxic crossmatches with her husband owing to pretransplantation blood transfusions. We performed a preconditioning regimen comprising a single dose of rituximab (375 mg/m(2)) combined with double-filtration plasmapheresis (DFPP) followed by low doses of intravenous immunoglobulin (DFPP/IVIG treatment). Tacrolimus (target trough level, 5-10 ng/mL) and mycophenolate mofetil (1500 mg/body) were started 2 weeks before the DFPP/IVIG treatment. After 6 DFPP/IVIG sessions, the crossmatch became negative. An induction quadruple immunosuppression protocol included tacrolimus, mycophenolate mofetil, basiliximab, and methylprednisolone. After the transplantation, the patient's immune status was evaluated regularly by mixed lymphocyte reactions (MLR) using an intracellular carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeling technique (CFSE-MLR assay) and immunosuppressant therapy was adjusted accordingly. During the observation period, neither antibody-mediated rejection nor acute cellular rejection was encountered in this patient.


Assuntos
Dessensibilização Imunológica , Glomerulonefrite por IGA/imunologia , Rejeição de Enxerto/prevenção & controle , Antígenos HLA/imunologia , Histocompatibilidade , Imunidade Celular , Imunidade Humoral , Falência Renal Crônica/cirurgia , Transplante de Rim/imunologia , Adulto , Anticorpos Monoclonais Murinos/administração & dosagem , Dessensibilização Imunológica/métodos , Feminino , Glomerulonefrite por IGA/complicações , Rejeição de Enxerto/imunologia , Teste de Histocompatibilidade , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Imunossupressores/administração & dosagem , Falência Renal Crônica/imunologia , Cinética , Doadores Vivos , Teste de Cultura Mista de Linfócitos , Plasmaferese , Rituximab , Resultado do Tratamento
8.
Artigo em Inglês | MEDLINE | ID: mdl-17347002

RESUMO

The embryonic modal value of heart rate (MHR) differs between broiler and White Leghorn chickens, but the initial development of cholinergic chronotropic control of embryonic heart rate (HR) does not. Thus, we hypothesized that hatchling MHR should also differ between broiler and White Leghorn strains, while the development of a physiological regulation, such as the endothermic HR response, should not be different between hatchlings of the two strains. To test this, we measured the response of HR and cloaca temperature (Tb) to alteration of ambient temperature (Ta); i.e., 35 degrees C-25 degrees C-35 degrees C, in four groups of hatchlings on Days 0 and 1 post-hatch. Fertile eggs of both strains with similar mass were incubated simultaneously in the same incubator. Eggs of broiler chickens hatched approximately 7 h earlier than White Leghorn chicken eggs. Chick mass at hatching was identical in both strains, but diverged during 2 days after hatching. Tb measured at the initial Ta of 35 degrees C was identical in both strains. MHR at the same Ta was approximately 30 bpm lower in broiler chicks than in White Leghorn chicks, but the difference was reversed to that observed in the embryos. The endothermic HR response was advanced by approximately 1 day in broiler chicks compared with White Leghorn chicks. As a result, eggs of similar mass in both strains produced chicks with similar mass and Tb at hatching, but during 2 days of post-hatch life their masses diverged and regulation of the endothermic HR response developed earlier in broiler than in White Leghorn hatchlings. This physiological heterochrony between strains is most likely due to genetic selection for fast growth in broiler chickens.


Assuntos
Animais Recém-Nascidos/fisiologia , Galinhas/fisiologia , Frequência Cardíaca/fisiologia , Animais , Temperatura Corporal , Peso Corporal , Cloaca , Tamanho do Órgão
9.
Respir Physiol Neurobiol ; 155(3): 286-92, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16843738

RESUMO

During hatching, there is a maturation of the mechanisms controlling the respiratory physiology involved in endotherm in precocial avian species. Here we examined the timing of the development of an endothermic response of oxygen uptake (MO2) to an alteration of ambient temperature (T(a)) in a model precocial species, the preterm and hatching emu (Dromaius novaehollandiae). Late stage pre-pipped and pipped embryos and hatchlings were measured for responses of MO2 and shell or skin temperature (T(s)) to altered T(a) (DeltaT(a)). MO2 remained unchanged in pre-pipped and internally pipped (IP) embryos at the end of 1.5h exposure to DeltaT(a) of +/-10 degrees C. Externally pipped (EP) embryos responded to a cooling and a warming exposure with marked increase and decrease in MO2, as hatchlings responded to DeltaT(a) with an endothermic change in MO2. The demonstration of the endothermic inverse metabolic response first appearing in EP embryos suggests that pre-EP embryos may also possess the ability to produce the endothermic inverse metabolic response, but they are restricted by the eggshell gas conductance. Late pre-pipped and IP embryos were measured again for responses of [Formula: see text] to DeltaT(a) in air and then in a 40% O(2) environment. The metabolic response of pre-pipped embryos at 90% of incubation was partially altered by switching from air to hyperoxia. IP embryos responded to DeltaT(a) in 40% O(2) with apparent inverse changes in MO2. The late stage emu embryo possesses the ability to produce an endothermic metabolic response at an earlier stage of development than in chickens, but this response is limited by the eggshell gas conductance.


Assuntos
Animais Recém-Nascidos/metabolismo , Animais Recém-Nascidos/fisiologia , Regulação da Temperatura Corporal/fisiologia , Dromaiidae/embriologia , Embrião não Mamífero/metabolismo , Embrião não Mamífero/fisiologia , Sistema Respiratório/embriologia , Animais , Casca de Ovo/fisiologia , Hiperóxia/metabolismo , Consumo de Oxigênio/fisiologia , Temperatura Cutânea/fisiologia , Temperatura
10.
Br J Cancer ; 94(6): 854-62, 2006 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-16508635

RESUMO

Weakly tumorigenic and nonmetastatic QR-32 cells derived from a fibrosarcoma in C57BL6 mouse are converted to malignant cells once they have grown after being coimplanted with a gelatine sponge which induces inflammation. We administered a newly developed peroral superoxide dismutase (SOD), oxykine, and as control vehicle, gliadin and saline, starting 2 days before the coimplantation and continued daily throughout the experiment. In the oxykine group, tumour incidence was lower (41%) than in the gliadin or saline group (83 and 79%, respectively). The inhibitory effect of oxykine was lost when an individual component of oxykine was administered, that is, SOD alone and gliadin alone. The effect was also abolished when administered by intraperitoneal route. When perfused in situ with nitroblue tetrazolium, an indicator of superoxide formation, the tumour masses from gliadin and saline groups displayed intense formazan deposition, whereas, those from oxykine group had less deposition. Enzymatic activity of SOD was also increased in oxykine group. Arising tumour cells in gliadin and saline groups acquired metastatic phenotype, but those in oxykine group showed reduced metastatic ability. These results suggested that the orally active SOD derivative prevented tumour progression promoted by inflammation, which is thought to be through scavenging inflammatory cell-derived superoxide anion.


Assuntos
Fibrossarcoma/imunologia , Fibrossarcoma/patologia , Inflamação , Metástase Neoplásica/imunologia , Superóxido Dismutase/metabolismo , Administração Oral , Animais , Progressão da Doença , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Superóxido Dismutase/administração & dosagem
11.
Artigo em Inglês | MEDLINE | ID: mdl-14720592

RESUMO

In chick (Gallus gallus domesticus) embryos, instantaneous heart rate begins to fluctuate with the appearance of rapid, transient decelerations at around the end of the second week of incubation. Previously, it was shown that instantaneous heart rate decelerations were eliminated by administration of atropine and concurrently heart rate baseline was elevated in late embryos. Because the previous study lacked statistical treatment and there has been recent controversy over the development of tonic vagal control of the heart, we reexamine the hypothesis that transient decelerations of instantaneous heart rate are mediated by vagus nerve and the vagal tone begins to appear at around the end of the second week of incubation. Atropine administration tests were conducted for sixty-seven 11- to 14-day-old and 18-day-old embryos in total. Heart rate decelerations appeared sporadically in three out of ten 12-day-old embryos, but the difference of mode heart rate before and after administration of atropine was not significant. Seven out of nine 13-day-old embryos and all nine 14-day-old embryos showed heart rate decelerations and the difference of mode heart rate before and after atropine administration was significant. In late (18-day-old) embryos, magnitude and frequency of instantaneous heart rate decelerations further increased with additional appearance of transient, irregular accelerations. Administration of varying doses of atropine completely eliminated the heart rate decelerations and elevated the heart rate baseline more markedly than in young embryos, indicating the maturation of vagal tone late in incubation.


Assuntos
Embrião de Galinha/inervação , Embrião de Galinha/fisiologia , Galinhas/fisiologia , Frequência Cardíaca/fisiologia , Animais , Atropina/farmacologia , Cateterismo Cardíaco , Eletrocardiografia , Coração/efeitos dos fármacos , Coração/fisiologia , Fatores de Tempo
12.
Am J Physiol Regul Integr Comp Physiol ; 286(1): R129-37, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14525724

RESUMO

On the basis of evidence showing that instantaneous heart rate (IHR) of chick hatchlings responds to exposure to altered ambient temperature (Ta; Tazawa H, Moriya K, Tamura A, and Akiyama R. Comp Biochem Physiol A 131A: 797-803, 2002), we elucidate here the developmental timeline for the homeothermic response of HR in newly hatched chicks (days 0-7) maintained at room temperature ( approximately 24-27 degrees C). Hatchlings were exposed to Ta of 25, 35, and 25 degrees C for 1-h periods, respectively, and IHR was measured together with skin temperature (Ts) during this warming and cooling bout. Early 0-day-old (0 day) chicks responded to warming and cooling exposures with various changes in HR baseline. In newly hatched chicks (0-7 h old), HR baseline was elevated during warming (Delta126 beats/min, n = 13) and declined during cooling (-Delta94 beats/min). With progress of development on day 0, the elevation of HR baseline during warming decreased and advanced 0-day chicks tended to decrease HR baseline during warming rather than increase HR. The more developed 1- to 7-day-old chicks exhibited the expected homeothermic decrease in HR during warming. The diurnal variations of HR responses during warming and cooling on the first day of post-egg life indicate that pronounced development of thermoregulatory competence occurs during the day of hatching (day 0). The response of IHR fluctuations to altered Ta was observed in the form of low- and high-frequency oscillations. High-frequency oscillations corresponding to respiratory sinus arrhythmia developed as the hatchlings aged. There was a significant increase in the number of chicks exhibiting both low- and high-frequency oscillations that depended on age and the development of thermoregulatory competence of hatchlings.


Assuntos
Envelhecimento/fisiologia , Animais Recém-Nascidos/fisiologia , Regulação da Temperatura Corporal/fisiologia , Galinhas/fisiologia , Frequência Cardíaca/fisiologia , Temperatura , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Galinhas/crescimento & desenvolvimento , Temperatura Baixa , Temperatura Alta , Oscilometria
13.
Artigo em Inglês | MEDLINE | ID: mdl-14511748

RESUMO

During the final stages of embryonic development in chickens, diffusive gas exchange through the chorioallantoic membrane (CAM) is progressively replaced by pulmonary respiration that begins with internal pipping (IP) of the CAM. Late chick embryos going through the transition from CAM respiration to pulmonary respiration were exposed to hyperoxic (100% O(2)) and hypoxic (10% O(2)/N(2)) environments for 2-h and the responses of baseline heart rate (HR), and HR fluctuation patterns were investigated. 16- and 18-day-old (referred to as 18-d) embryos and 20-d externally pipped (EP) embryos were examined as pre-pipped embryos and pipped embryos, respectively. 19-d embryos were divided into two groups: embryos that had not yet internally pipped (Pre-IP embryos) and embryos that had internally pipped (IP embryos). IP was identified by detecting the breathing signal with a condenser microphone attached hermetically on the eggshell (i.e. acoustorespirogram) on day 19 of incubation. In the hyperoxic environment, HR baseline of pre-pipped embryos remained unchanged and that of pipped embryos was depressed. In the hypoxic environment, HR baseline of 16-d pre-pipped embryos was depressed and that of pipped (IP and EP) embryos elevated. These different responses in pipped embryos might be partially attributed to increased cholinergic input from the vagus nerve in hyperoxia and increased adrenergic response in hypoxia. While hyperoxia did not induce marked modification of instantaneous heart rate (IHR) fluctuation patterns, hypoxia tended to augment transient decelerations of IHR in late pre-pipped embryos and markedly depressed HR fluctuations in pipped embryos.


Assuntos
Alantoide/metabolismo , Embrião de Galinha , Córion/metabolismo , Gases/metabolismo , Frequência Cardíaca , Hiperóxia/fisiopatologia , Hipóxia/fisiopatologia , Animais , Difusão
14.
Artigo em Inglês | MEDLINE | ID: mdl-12814791

RESUMO

Among fluctuations of instantaneous heart rate (IHR) in newly hatched chicks, heart rate (HR) oscillation with a mean frequency of 0.7 Hz has been designated as Type II HR variability characterized by low frequency (LF) oscillation [Comp. Biochem. Physiol. Part A 124 (1999) 461]. In response to exposure to lowered ambient temperature (Ta), chick hatchlings raised their HR baseline accompanied with the production or augmentation of Type II HR oscillation, indicating that LF oscillation is a phenomenon relating to thermoregulation [J. Therm. Biol. 26 (2001) 281]. In emu hatchlings that are precocial like chickens, Type II HR oscillation also occurred, but less frequently in comparison with chick hatchlings [Comp. Biochem. Physiol. Part A 131 (2002) 787]. This present experiment was conducted to elucidate how IHR of emu hatchlings responds to changes in Ta. Six hatchlings were measured for IHR and skin temperature (Ts) during a 3-h period when they were exposed to controlled Ta (ca. 35 degrees C), lowered Ta (ca. 15-30 degrees C) and again the controlled Ta for individual 1-h periods. In response to all the cooling and re-warming procedures, HR baseline changed depending upon the intensity of the Ta differences; i.e. large differences of Ta produced large changes in HR. HR fluctuations tended to augment during cooling with a few exceptions, but LF oscillation was not produced. Thus, LF oscillation, which was scarce even at the controlled Ta, could not be used as a thermoregulatory indicator in emus.


Assuntos
Temperatura Baixa , Dromaiidae/fisiologia , Frequência Cardíaca , Animais
15.
Br Poult Sci ; 44(5): 761-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14965099

RESUMO

1. Among three types of fluctuations of instantaneous heart rate (IHR) found previously in newly hatched chicks, a high frequency oscillation with a mean frequency of about 0.7 Hz (Type I) appeared to be concurrent with breathing (Moriya et al., Comparative Biochemistry and Physiology, 124A: 461-468, 1999). 2. In order to confirm that Type I HR fluctuation is respiratory sinus arrhythmia (RSA), breathing activity was measured by a condenser microphone, simultaneously with IHR. 3. The microphone detected pressure changes caused by breathing (acoustorespirogram, ARG) and also unexpectedly movement, probably twitch, of hatchlings. 4. Simultaneous measurements of IHR and ARG demonstrated that oscillatory frequency of Type I HR fluctuation coincided with breathing frequency and IHR increased with inspiration, confirming that Type I HR oscillation is RSA. 5. In addition, large transient HR accelerations (Type III HR fluctuation) simultaneously occurred with movement or twitch of the hatchlings, suggesting that Type III HR fluctuation and movement of hatchlings have the same origin, probably sympathetic nerve function.


Assuntos
Envelhecimento/fisiologia , Galinhas/crescimento & desenvolvimento , Frequência Cardíaca/fisiologia , Mecânica Respiratória/fisiologia , Animais , Embrião de Galinha/fisiologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-11897188

RESUMO

Emu eggs weigh approximately 600 g and have an incubation duration (ID) of approximately 50 days. The egg mass is approximately 10-fold heavier than the chicken egg and the ID is approximately 2.5-fold longer. Daily changes in mean heart rate (MHR) of emu embryos were previously determined, but further measurement was needed to investigate the species-specific behavior of cardiac rhythm for comparison with other species. In the present study, we continuously measured the electrocardiogram of emu embryos while maintaining adequate gas exchange through the eggshell and determined instantaneous heart rate (IHR) during the last 2-7 days of incubation until hatching or death. The MHR over 1-min intervals was calculated from IHR data in order to present continuous developmental patterns of heart rate (HR) in a single graph and 24-h recordings of HR in a single panel, showing the HR trend over a prolonged period. However, neither circadian nor ultradian rhythms of HR were shown in these figures or by power spectrum analysis. The IHR distinctively fluctuated and the fluctuations were mainly comprised of three patterns of irregular HR accelerations in embryos that hatched. Respiratory sinus arrhythmia also occurred in perinatal embryos. During the final stages of the perinatal period, short-term, repeated, large accelerations of IHR appeared, which signaled imminent hatching and has been reported for chick embryos. IHR fluctuations in embryos that failed to hatch tended to become inactive towards death.


Assuntos
Dromaiidae/embriologia , Embrião não Mamífero/fisiologia , Frequência Cardíaca , Animais , Desenvolvimento Embrionário
17.
Artigo em Inglês | MEDLINE | ID: mdl-11897189

RESUMO

Six emu hatchlings were non-invasively measured for electrocardiogram (ECG) from their chest wall using flexible electrodes, and the instantaneous heart rate (IHR) was determined from ECG throughout the first week of post-hatching life. Although the baseline heart rate (HR) was low, approximately 100-200 beats per min (bpm), compared with chick hatchlings, the IHR fluctuated markedly. The fluctuation of IHR comprised HR variability and irregularities that were designated as types I, II and III in chick hatchlings and additional large accelerations distinctive of emu hatchlings. Type I was HR oscillation with a mean frequency of 0.37 Hz (range 0.2-0.7 Hz), i.e. respiratory sinus arrhythmia (RSA). From RSA, breathing frequency in emu hatchlings was estimated to be approximately half of that in chickens. Type II HR oscillation was also found in the emu; the frequency ranged from approximately 0.04 to 0.1 with a mean of 0.06 Hz, and the magnitude tended to be large compared with that of chickens. In addition to type III HRI, which was designated in chickens, large, irregular HR accelerations were characteristic of emu hatchlings. From IHR data, developmental patterns of mean heart rate (MHR) were constructed and plotted on a single graph to inspect the diurnal rhythm of MHR by visual inspection and power spectrum analysis. A circadian rhythm was not clear in the emu hatchlings, in contrast to chick hatchlings, which showed a dominant diurnal rhythm.


Assuntos
Animais Recém-Nascidos/fisiologia , Dromaiidae/fisiologia , Frequência Cardíaca , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Dromaiidae/crescimento & desenvolvimento
18.
Artigo em Inglês | MEDLINE | ID: mdl-11897192

RESUMO

In chick embryos, gas exchange takes place via the chorioallantoic membrane (CAM) and the lungs at approximately 1 day prior to hatching. The present study was designed to elucidate the development of respiratory rhythms in the chick embryo during the whole pipping (perinatal) period with a condenser-microphone measuring system. The microphone was hermetically attached on the eggshell over the air cell on day 18 of incubation. It first detected a cardiogenic signal (i.e. acoustocardiogram), and then beak clapping and breathing signals (acoustorespirogram, ARG). The first signals of lung ventilation appeared intermittently and irregularly approximately once per 5 s among the clapping signals after the embryo penetrated its beak into the air cell (internal pipping, IP). The respiratory rhythm then developed irregularly, with a subsequent more regular rate. The envelope pattern of breathing from the onset of IP through external pipping (EP) to hatching was constructed by a specially devised procedure, which eliminated external and internal noises. The envelope patterns indicated that the IP, EP and whole perinatal periods of 10 embryos were 14.1+/-6.4 (S.D.), 13.6+/-4.0 and 27.6+/-5.4 h, respectively. In addition, they also indicated the period of embryonic hatching activity (i.e. climax) which was 48+/-19 min. The development of respiratory rhythm was also shown by the instantaneous respiratory rate (IRR) which was designated as an inverse value of two adjacent ARG waves.


Assuntos
Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário , Respiração , Animais , Embrião de Galinha
19.
Cytogenet Genome Res ; 98(1): 108A, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12601245

RESUMO

Southern hybridization analysis of the MASP1 gene using an intron-specific probe detected a single band. An exon-specific probe detected several bands. PCR of genomic DNA using several exon-specific primer sets of MASP1 produced short and long products. Sequence of the shorter products corresponded to the processed pseudogene of MASP1. By fluorescence in situ hybridization, this pseudogene (MASP1P1) was mapped to 1p34.


Assuntos
Cromossomos Humanos Par 1 , Cromossomos Humanos Par 3 , Pseudogenes , Serina Endopeptidases/genética , Sequência de Aminoácidos , Sequência de Bases , Southern Blotting , Mapeamento Cromossômico , Clonagem Molecular , Primers do DNA , DNA Complementar/genética , Humanos , Hibridização in Situ Fluorescente , Serina Proteases Associadas a Proteína de Ligação a Manose , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Serina Endopeptidases/química
20.
Med Eng Phys ; 23(2): 111-5, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11413063

RESUMO

This paper presents the application of a neural network to predict human heart rate. Electrocardiograms were measured from 5 healthy adult human subjects and 5 data sets were constructed calculating instantaneous heart rate from the measured signal. The nonlinear radial basis function neural network was applied to have a one step ahead prediction of the 1000 point heart rate. The results of the prediction are compared to that obtained by a linear autoregressive model. The results show that the neural network performs better than the autoregressive model in predicting heart rate for 2 data sets while for the other 3 data sets the performance of the two models is statistically similar. This indicates that the heart rate may be controlled nonlinearly by the autonomic nervous system.


Assuntos
Frequência Cardíaca/fisiologia , Modelos Cardiovasculares , Redes Neurais de Computação , Adulto , Sistema Nervoso Autônomo/fisiologia , Engenharia Biomédica , Eletrocardiografia/estatística & dados numéricos , Humanos , Modelos Lineares , Dinâmica não Linear
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