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1.
Clin Hemorheol Microcirc ; 83(3): 207-215, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36565106

RESUMO

BACKGROUND: Venous malformations tend to retain their slow-flow behavior, even in progressive disease or regression following therapy. OBJECTIVE: The aim of this study is to analyze the development of acquired hemodynamic relevant arterio-venous fistulae in patients with slow-flow malformations. METHODS: This study is a retrospective analysis based on a consecutive local registry at a tertiary care Interdisciplinary Center for Vascular Anomalies. Patients with venous malformations and development of secondary arterio-venous fistulae were included. Indications for therapy of the vascular malformation were based on patients' symptoms and complications. The following endpoints were of clinical interest and were assessed: origin of development of arteriovenous fistula, development of secondary comorbidities as a result of the vascular malformation. For analysis we focused on descriptive statistics. RESULTS: Out of 1213 consecutive patients with vascular malformations, in 6 patients perfusion changed from slow flow to arterio-venous fast-flow patterns. Four patients developed the fistula after local trauma in the area of the malformation, the other 2 patients developed the fistula due to progression of the disease and recurrent thrombophlebitis. These 2 patients had no trauma or interventions at the time of arterio-venous fistula development. CONCLUSIONS: Acquired arterio-venous fast-flow fistula in patients with slow flow vascular malformation is very rare and might be a result of local trauma or the progression of the disease with recurrent thrombophlebitis. Specific evidence-based treatment options for these patients do not exist.


Assuntos
Fístula Arteriovenosa , Tromboflebite , Malformações Vasculares , Humanos , Estudos Retrospectivos , Malformações Vasculares/complicações , Fístula Arteriovenosa/complicações , Tromboflebite/complicações
2.
Clin Exp Dermatol ; 47(1): 43-49, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34236712

RESUMO

BACKGROUND: Vascular malformations of the genitalia often go undetected in clinical examination. These vascular malformations can cause a variety of clinical symptoms such as swelling, pain and bleeding. AIM: To characterize the distribution patterns of genital vascular malformations using magnetic resonance imaging (MRI) and to correlate these patterns with clinical findings in order to guide diagnostic decisions. METHODS: A retrospective analysis of MRIs of the pelvis and legs in 370 patients with vascular malformation was performed to determine the involvement of the internal and external genitalia. RESULTS: In 71 patients (19%), genital involvement could be identified by MRI. Of these, 11.3% (8 of 71) presented with internal involvement, 36.6% (26 of 71) with external involvement and 52.1% (37 of 71) with both internal and external involvement. Over half (57.1%) of the 49 patients with visible external genital signs detected during a clinical examination had additional internal genital involvement. CONCLUSIONS: Genital involvement is a common finding in patients with vascular malformation of the legs and/or pelvis. Based on our data, we recommend MRI of the legs and pelvic region in patients with externally visible signs of a vascular malformation of the external genitalia in order to exclude additional internal involvement.


Assuntos
Genitália/irrigação sanguínea , Imageamento por Ressonância Magnética , Malformações Vasculares/diagnóstico por imagem , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Malformações Vasculares/patologia , Adulto Jovem
3.
Conserv Physiol ; 7(1): coz011, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31110763

RESUMO

A strength of physiological ecology is its incorporation of aspects of both species' ecology and physiology; this holistic approach is needed to address current and future anthropogenic stressors affecting elasmobranch fishes that range from overexploitation to the effects of climate change. For example, physiology is one of several key determinants of an organism's ecological niche (along with evolutionary constraints and ecological interactions). The fundamental role of physiology in niche determination led to the development of the field of physiological ecology. This approach considers physiological mechanisms in the context of the environment to understand mechanistic variations that beget ecological trends. Physiological ecology, as an integrative discipline, has recently experienced a resurgence with respect to conservation applications, largely in conjunction with technological advances that extended physiological work from the lab into the natural world. This is of critical importance for species such as elasmobranchs (sharks, skates and rays), which are an especially understudied and threatened group of vertebrates. In 2017, at the American Elasmobranch Society meeting in Austin, Texas, the symposium entitled `Applications of Physiological Ecology in Elasmobranch Research' provided a platform for researchers to showcase work in which ecological questions were examined through a physiological lens. Here, we highlight the research presented at this symposium, which emphasized the strength of linking physiological tools with ecological questions. We also demonstrate the applicability of using physiological ecology research as a method to approach conservation issues, and advocate for a more available framework whereby results are more easily accessible for their implementation into management practices.

4.
Radiologe ; 58(Suppl 1): 29-33, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29796772

RESUMO

BACKGROUND: Abdominal lymphatic malformations (LM) are relatively rare findings in the differential diagnosis of focal abdominal lesions; however, they represent a challenge especially in younger patients. The aim of this review article is to provide up-to-date information about the different kinds of LM manifestations. In addition, related syndromes and typical imaging features to facilitate the diagnosis are discussed. RESULTS: The clinical presentation of abdominal LM is unspecific, whereby most are asymptomatic and comprise incidental findings of thin-walled cystic masses anywhere in the abdomen. The fluid in the cystic masses may be proteinaceous, contain blood, or be infected. Radiological imaging features overlap with other cystic diseases; hallmark in LM is a lack of a solid component and exclusive enhancement of the walls and septa. CONCLUSION: In cystic abdominal masses in early childhood or young adults, abdominal LM must be taken into account by the radiologist. Newly defined entities in this spectrum of diseases are central conducting lymphatic anomaly (CCLA) and generalized lymphatic anomaly (GLA).


Assuntos
Abdome/fisiopatologia , Cistos , Anormalidades Linfáticas , Pré-Escolar , Diagnóstico Diferencial , Humanos , Ultrassonografia/métodos , Adulto Jovem
5.
Radiologe ; 58(1): 19-24, 2018 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-29242954

RESUMO

BACKGROUND: Abdominal lymphatic malformations (LM) are relatively rare findings in the differential diagnosis of focal abdominal lesions; however, they represent a challenge especially in younger patients. The aim of this review article is to provide up-to-date information about the different kinds of LM manifestations. In addition, related syndromes and typical imaging features to facilitate the diagnosis are discussed. RESULTS: The clinical presentation of abdominal LM is unspecific, whereby most are asymptomatic and comprise incidental findings of thin-walled cystic masses anywhere in the abdomen. The fluid in the cystic masses may be proteinaceous, contain blood, or be infected. Radiological imaging features overlap with other cystic diseases; hallmark in LM is a lack of a solid component and exclusive enhancement of the walls and septae. CONCLUSION: In cystic abdominal masses in early childhood or young adults, abdominal LM must be taken into account by the radiologist. Newly defined entities in this spectrum of diseases are central conducting lymphatic anomaly (CCLA) and generalized lymphatic anomaly (GLA).


Assuntos
Abdome , Doenças Linfáticas , Diagnóstico Diferencial , Humanos , Radiografia
6.
Conserv Physiol ; 3(1): cov002, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27293687

RESUMO

Accurate measurements of blood gases and acid-base status require an array of sophisticated laboratory equipment that is typically not available during field research; such is the case for many studies on the stress physiology, ecology and conservation of elasmobranch fish species. Consequently, researchers have adopted portable clinical analysers that were developed for the analysis of human blood characteristics, but often without thoroughly validating these systems for their use on fish. The aim of our study was to test the suitability of the i-STAT system, the most commonly used portable clinical analyser in studies on fish, for analysing blood gases and acid-base status in elasmobranchs, over a broad range of conditions and using the sandbar shark (Carcharhinus plumbeus) as a model organism. Our results indicate that the i-STAT system can generate useful measurements of whole blood pH, and the use of appropriate correction factors may increase the accuracy of results. The i-STAT system was, however, unable to generate reliable results for measurements of partial pressure of oxygen (PO2) and the derived parameter of haemoglobin O2 saturation. This is probably due to the effect of a closed-system temperature change on PO2 within the i-STAT cartridge and the fact that the temperature correction algorithms used by i-STAT assume a human temperature dependency of haemoglobin-O2 binding; in many ectotherms, this assumption will lead to equivocal i-STAT PO2 results. The in vivo partial pressure of CO2 (PCO2) in resting sandbar sharks is probably below the detection limit for PCO2 in the i-STAT system, and the measurement of higher PCO2 tensions was associated with a large measurement error. In agreement with previous work, our results indicate that the i-STAT system can generate useful data on whole blood pH in fishes, but not blood gases.

7.
Sci Rep ; 4: 5431, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24961164

RESUMO

IL-17 has emerged as a key player in the immune system, exhibiting roles in protection from infectious diseases and promoting inflammation in autoimmunity. Initially thought to be CD4 T-cell-derived, the sources of IL-17 are now known to be varied and belong to both the innate and adaptive arms of the immune system. Mechanisms for inducing IL-17 production in lymphoid cells are thought to rely on appropriate antigenic stimulation in the context of TGF-ß1, IL-6 and/or IL-1ß. Using culture protocols adapted from human studies, we have effectively induced both bovine CD4(+) and WC1(+) γδ T-cells to produce IL-17 termed Th17 and γδ17 cells, respectively. The negative regulatory effect of IFN-γ on mouse and human IL-17 production can be extended to the bovine model, as addition of IFN-γ decreases IL-17 production in both cell types. Furthermore we show that infection with the protozoan Neospora caninum will induce fibroblasts to secrete pro-IL-17 factors thereby inducing a γδ17 phenotype that preferentially kills infected target cells. Our study identifies two T-cell sources of IL-17, and is the first to demonstrate a protective effect of IL-17(+) T-cells in ruminants. Our findings offer further opportunities for future adjuvants or vaccines which could benefit from inducing these responses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Interleucina-17/imunologia , Glicoproteínas de Membrana/imunologia , Neospora/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Células Th17/imunologia , Animais , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/parasitologia , Bovinos , Células Cultivadas , Chlorocebus aethiops , Técnicas de Cocultura , Citotoxicidade Imunológica/imunologia , Fibroblastos/imunologia , Fibroblastos/metabolismo , Fibroblastos/parasitologia , Interações Hospedeiro-Parasita/imunologia , Interferon gama/imunologia , Interferon gama/farmacologia , Interleucina-17/metabolismo , Interleucina-6/imunologia , Interleucina-6/farmacologia , Glicoproteínas de Membrana/metabolismo , Neospora/fisiologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Células Th17/efeitos dos fármacos , Células Th17/metabolismo , Fatores de Tempo , Fator de Crescimento Transformador beta1/imunologia , Fator de Crescimento Transformador beta1/farmacologia , Células Vero
8.
Pathologe ; 35(2): 173-6, 2014 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-24619528

RESUMO

This article presents the case of a 43-year-old male patient with recurrent painful swelling of the right submandibular gland. Submandibulectomy was performed. Histological investigations showed an intense granulomatous inflammation with severe destruction of the parenchyma. The inflammatory infiltrate consisted of abscesses with neutrophilic and eosinophilic granulocytes and ill-defined granulomas with multinucleated giant cells. Some of the blood vessels showed evidence of vasculitis. After further clinical and serological investigations with highly elevated levels of cytoplasmic antineutrophil cytoplasmic antibodies (c-ANCA) and antiproteinase-3 antibodies, a rare limited disease of granulomatous polyangiitis (Wegener granulomatosis) was finally diagnosed. Such a manifestation of the disease is exceedingly rare; therefore, only single case reports have so far been described. The certain establishment of the diagnosis seems to be challenging because of the lack of involvement of the respiratory tract and the kidneys. In this case a histological assessment and clinical findings are mandatory for the correct diagnosis.


Assuntos
Sialadenite/diagnóstico , Sialadenite/patologia , Doenças da Glândula Submandibular/diagnóstico , Adulto , Anticorpos Anticitoplasma de Neutrófilos/sangue , Autoanticorpos/sangue , Diagnóstico Diferencial , Granuloma/patologia , Granuloma/cirurgia , Humanos , Masculino , Mieloblastina/imunologia , Necrose , Sialadenite/cirurgia , Glândula Submandibular/patologia , Glândula Submandibular/cirurgia , Doenças da Glândula Submandibular/patologia , Doenças da Glândula Submandibular/cirurgia , Tomografia Computadorizada por Raios X
9.
J Fish Biol ; 81(3): 1043-58, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22880736

RESUMO

To quantify the tolerance of summer flounder Paralichthys dentatus to episodic hypoxia, resting metabolic rate, oxygen extraction, gill ventilation and heart rate were measured during acute progressive hypoxia at the fish's acclimation temperature (22° C) and after an acute temperature increase (to 30° C). Mean ±s.e. critical oxygen levels (i.e. the oxygen levels below which fish could not maintain aerobic metabolism) increased significantly from 27 ± 2% saturation (2·0 ± 0·1 mg O(2) l(-1)) at 22° C to 39 ± 2% saturation (2·4 ± 0·1 mg O(2) l(-1)) at 30° C. Gill ventilation and oxygen extraction changed immediately with the onset of hypoxia at both temperatures. The fractional increase in gill ventilation (from normoxia to the lowest oxygen level tested) was much larger at 22° C (6·4-fold) than at 30° C (2·7-fold). In contrast, the fractional decrease in oxygen extraction (from normoxia to the lowest oxygen levels tested) was similar at 22° C (1·7-fold) and 30° C (1·5-fold), and clearly smaller than the fractional changes in gill ventilation. In contrast to the almost immediate effects of hypoxia on respiration, bradycardia was not observed until 20 and 30% oxygen saturation at 22 and 30° C, respectively. Bradycardia was, therefore, not observed until below critical oxygen levels. The critical oxygen levels at both temperatures were near or immediately below the accepted 2·3 mg O(2) l(-1) hypoxia threshold for survival, but the increase in the critical oxygen level at 30° C suggests a lower tolerance to hypoxia after an acute increase in temperature.


Assuntos
Doenças dos Peixes/fisiopatologia , Hipóxia/veterinária , Temperatura , Análise de Variância , Animais , Linguado/fisiologia , Brânquias/metabolismo , Frequência Cardíaca/fisiologia , Hipóxia/fisiopatologia , Oxigênio/metabolismo , Consumo de Oxigênio
10.
J Fish Biol ; 79(1): 235-55, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21722122

RESUMO

The resting metabolic rates (R(R)) of western North Atlantic Ocean sciaenids, such as Atlantic croaker Micropogonias undulatus, spot Leiostomus xanthurus and kingfishes Menticirrhus spp., as well as the active metabolic rates (R(A)) of M. undulatus and L. xanthurus were investigated to facilitate inter and intraspecific comparisons of their energetic ecology. The R(R) of M. undulatus and L. xanthurus were typical for fishes with similar lifestyles. The R(R) of Menticirrhus spp. were elevated relative to those of M. undulatus and L. xanthurus, but below those of high-energy-demand species such as tunas Thunnus spp. and dolphinfish Coryphaena hippurus. Repeated-measures non-linear mixed-effects models were applied to account for within-individual autocorrelation and corrected for non-constant variance typical of noisy R(A) data sets. Repeated-measures models incorporating autoregressive first-order [AR(1)] and autoregressive moving average (ARMA) covariances provided significantly superior fits, more precise parameter estimates (i.e. reduced s.e.) and y-intercept estimates that more closely approximated measured R(R) for M. undulatus and L. xanthurus than standard least-squares regression procedures.


Assuntos
Metabolismo Basal , Perciformes/metabolismo , Animais , Oceano Atlântico , Modelos Estatísticos , Oxigênio/metabolismo
11.
J Fish Biol ; 78(2): 651-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21284642

RESUMO

Monophasic action potentials (MAPs) were recorded from the spongy and compact layers of the yellowfin tuna Thunnus albacares ventricle as stimulation frequency was increased. MAP duration decreased with increase in stimulation frequency in both the spongy and compact myocardial layers, but no significant difference in MAP duration was observed between the layers.


Assuntos
Potenciais de Ação , Ventrículos do Coração , Miocárdio , Atum/fisiologia , Animais , Estimulação Elétrica , Eletrodos
12.
Aquat Toxicol ; 71(1): 1-12, 2005 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-15642627

RESUMO

Cytochrome P4501A (CYP1A) monoxygenase, vitellogenin (Vtg) and Zona radiata proteins (Zrp) are frequently used as biomarkers of fish exposure to organic contaminants. In this work, swordfish liver sections obtained from the Mediterranean Sea, the South African coasts (South Atlantic and South Western Indian Oceans) and the Central North Pacific Ocean were immunostained with antisera against CYP1A, Zrp, and Vtg. CYP1A induction was found in hepatocytes, epithelium of the biliary ductus and the endothelium of large blood vessels of fish from the Mediterranean Sea and South African waters, but not from the Pacific Ocean. Zrp and Vtg were immunolocalized in hepatocytes of male swordfish from the Mediterranean Sea and from South African waters. Plasma Dot-Blot analysis, performed in Mediterranean and Pacific specimens, revealed the presence of Zrp and Vtg in males from Mediterranean but not from Pacific. These results confirm previous findings about the potential exposure of Mediterranean swordfish to endocrine, disrupting chemicals and raise questions concerning the possible presence of xenobiotic contaminants off the Southern coasts of South Africa in both the South Atlantic and South Western Indian Oceans.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Proteínas do Ovo/metabolismo , Fígado/metabolismo , Perciformes/metabolismo , Vitelogeninas/metabolismo , Animais , Biomarcadores/sangue , Western Blotting , Feminino , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Imuno-Histoquímica , Fígado/enzimologia , Masculino , Oceanos e Mares , Poluentes Químicos da Água/intoxicação
13.
Clin Neuropsychol ; 17(3): 383-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14704888

RESUMO

There is an emergent need for base rate data on symptom validity tests (SVTs) in clinical populations that are likely to seek disability benefits. The inclusion of HIV under the Americans with Disabilities Act has prompted many persons with HIV-1 infection to apply for disability, which raises the concern that a subset of these individuals might feign cognitive deficits to obtain benefits. This brief report provides base rate data on one SVT, the Hiscock Digit Memory Test (HDMT), in a sample of 82 non-compensation-seeking, neuropsychologically impaired participants who met diagnostic criteria for an HIV-associated neurocognitive disorder. Approximately 98% of individuals with HIV-associated neurocognitive disorders performed above an established HDMT cutoff for suboptimal effort (i.e., HDMT> or =90% accuracy), whilst 95% of the sample obtained perfect scores. Clinicians can therefore be confident that, in the absence of severe dementia or amnesia, HDMT scores below standard cutoffs are unlikely to be solely attributable to HIV-associated cognitive impairment.


Assuntos
Transtornos Cognitivos/etiologia , Infecções por HIV/complicações , Memória , Testes Neuropsicológicos , Adulto , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
14.
J Acoust Soc Am ; 109(4): 1717-22, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11325139

RESUMO

Devices known as jawphones have previously been used to measure interaural time and intensity discrimination in dolphins. This study introduces their use for measuring hearing sensitivity in dolphins. Auditory thresholds were measured behaviorally against natural background noise for two bottlenose dolphins (Tursiops truncatus); a 14-year-old female and a 33-year-old male. Stimuli were delivered to each ear independently by placing jawphones directly over the pan bone of the dolphin's lower jaw, the assumed site of best reception. The shape of the female dolphin's auditory functions, including comparison measurements made in the free field, favorably matches that of the accepted standard audiogram for the species. Thresholds previously measured for the male dolphin at 26 years of age indicated a sensitivity difference between the ears of 2-3 dB between 4-10 kHz, which was considered unremarkable at the time. Thresholds for the male dolphin reported in this study suggest a high-frequency loss compared to the standard audiogram. Both of the male's ears have lost sensitivity to frequencies above 55 kHz and the right ear is 16-33 dB less sensitive than the left ear over the 10-40 kHz range, suggesting that males of the species may lose sensitivity as a function of age. The results of this study support the use of jawphones for the measurement of dolphin auditory sensitivity.


Assuntos
Percepção Auditiva/fisiologia , Golfinhos/fisiologia , Auxiliares de Audição , Transtornos da Audição/diagnóstico , Arcada Osseodentária , Animais , Audiometria/métodos , Feminino , Masculino , Ruído , Sensibilidade e Especificidade
16.
J Comp Physiol B ; 168(6): 405-18, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9747521

RESUMO

In fishes, catecholamines increase red blood cell intracellular pH through stimulation of a sodium/proton (Na+/H+) antiporter. This response can counteract potential reductions in blood O2 carrying capacity (due to Bohr and Root effects) when plasma pH and intracellular pH decrease during hypoxia, hypercapnia, or following exhaustive exercise. Tuna physiology and behavior dictate exceptionally high rates of O2 delivery to the tissues often under adverse conditions, but especially during recovery from exhaustive exercise when plasma pH may be reduced by as much as 0.4 pH units. We hypothesize that blood O2 transport during periods of metabolic acidosis could be especially critical in tunas and the response of rbc to catecholamines elevated to an extreme. We therefore investigated the in vitro response of red blood cells from yellowfin tuna (Thunnus albacares) and skipjack tuna (Katsuwonus pelamis) to catecholamines. Tuna red blood cells had a typical response to catecholamines, indicated by a rapid decrease in plasma pH. Amiloride reduced the response, whereas 4,4'diisothiocyanatostilbene-2,2'-disulphonic acid enhanced both the decrease in plasma pH and the increase in intracellular pH. Changes in plasma [Na+], [Cl-], and [K+] were consistent with the hypothesis that tuna red blood cells have a Na+/H+ antiporter similar to that described for other teleost red blood cells. Red blood cells from both tuna species were more responsive to noradrenaline than adrenaline. At identical catecholamine concentrations, the decrease in plasma pH was greater in skipjack tuna blood, the more active of the two tuna species. Based on changes in plasma pH, the response of red blood cells to catecholamines from both tuna species was less than that of rainbow trout (Oncorhynchus mykiss) red blood cells, but greater than that of cod (Gadus morhua) red blood cells. Noradrenaline had no measurable influence on the O2 affinity of skipjack tuna blood and only slightly increased the O2 affinity of yellowfin tuna blood. Our results, therefore, do not support our original hypothesis. The catecholamine response of red blood cells from high-energy-demand teleosts (i.e., tunas) is not enhanced compared to other teleosts. There are data on changes in cardio-respiratory function in tunas caused by acute hypoxia and modest increases in activity, but there are no data on the changes in cardio-respiratory function in tunas accompanying the large increases in metabolic rate seen during recovery from exhaustive exercise. However, we conclude that during those instances where high rates of O2 delivery to the tissues are needed, tunas' ability to increase cardiac output, ventilation volume, blood O2 carrying capacity, and effective respiratory (i.e., gill) surface area are probably more important than are the responses of red blood cells to catecholamines. We also use our data to investigate the extent of the Haldane effect and its relationship to blood O2 and CO2 transport in yellowfin tuna. Yellowfin tuna blood shows a large Haldane effect; intracellular pH increases 0.20 units during oxygenation. The largest change in intracellular pH occurs between 40-100% O2 saturation, indicating that yellowfin tuna, like other teleosts, fully exploit the Haldane effect over the normal physiological range of blood O2 saturation.


Assuntos
Catecolaminas/farmacologia , Eritrócitos/efeitos dos fármacos , Atum/sangue , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Agonistas alfa-Adrenérgicos/farmacologia , Amilorida/farmacologia , Animais , Transporte Biológico , Dióxido de Carbono/metabolismo , Diuréticos/farmacologia , Relação Dose-Resposta a Droga , Epinefrina/farmacologia , Eritrócitos/metabolismo , Concentração de Íons de Hidrogênio , Norepinefrina/farmacologia , Oxigênio/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Especificidade da Espécie
17.
J Exp Biol ; 201 (Pt 12): 647-54, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9450974

RESUMO

We measured red cell space with 51Cr-labeled red blood cells, and dextran space with 500 kDa fluorescein-isothiocyanate-labeled dextran (FITC-dextran), in two groups of yellowfin tuna (Thunnus albacares). Red cell space was 13.8+/-0.7 ml kg-1 (mean +/- s.e.m.) Assuming a whole-body hematocrit equal to the hematocrit measured at the ventral aortic sampling site and no significant sequestering of 51Cr-labeled red blood cells by the spleen, blood volume was 46. 7+/-2.2 ml kg-1. This is within the range reported for most other teleosts (30-70 ml kg-1), but well below that previously reported for albacore (Thunnus alalunga, 82-197 ml kg-1). Plasma volume within the primary circulatory system (calculated from the 51Cr-labeled red blood cell data) was 32.9+/-2.3 ml kg-1. Dextran space was 37.0+/-3.7 ml kg-1. Because 500 kDa FITC-dextran appeared to remain within the vascular space, these data imply that the volume of the secondary circulatory system of yellowfin tuna is small, and its exact volume is not measurable by our methods. Although blood volume is not exceptional, circulation time (blood volume/cardiac output) is clearly shorter in yellowfin tuna than in other active teleosts. In a 1 kg yellowfin tuna, circulation time is approximately 0.4 min (47 ml kg-1/115 ml min-1 kg-1) compared with 1. 3 min (46 ml kg-1/35 ml min-1 kg-1) in yellowtail (Seriola quinqueradiata) and 1.9 min (35 ml kg-1/18 ml min-1 kg-1) in rainbow trout (Oncorhynchus mykiss). In air-breathing vertebrates, high metabolic rates are necessarily correlated with short circulation times. Our data are the first to imply that a similar relationship occurs in fishes.

19.
Comp Biochem Physiol A Physiol ; 113(1): 25-31, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8729736

RESUMO

We summarize our morphometric data on fiber vascularization and aerobic capacity in red muscle of tuna (Katsuwonus pelamis), compared to intensely aerobic flight muscles of hummingbird (Selasphorus rufus, BW 3-4 g) and bat (Eptesius fuscus, BW 15-16 g, Pipistrellus hesperus, BW 3-5 g). Three characteristic features of high flux paths for oxygen: (a) small fiber size, (b) dense capillary network and (c) high mitochondrial volume density were found in tuna, but they were not as pronounced as in hummingbird and bat flight muscles. A particular arrangement of capillary manifolds, also seen in flight muscle of birds but not in bats, was found in tuna, forming dense envelopes of capillary branches around portions of muscle fibers. However, all indexes of fiber capillarization were relatively low in tuna red muscle for its mitochondrial volume, compared with other intensely aerobic muscles. Capillary length per unit volume of mitochondria, and capillary surface per mitochondrial inner (and outer) membrane surface area, were about one half of those in hummingbird or bat flight muscles. Consistent differences exist in the size of the capillary network for the size of the mitochondrial compartment in highly aerobic red muscle of tuna compared with bird and mammal.


Assuntos
Aves/metabolismo , Mamíferos/metabolismo , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Oxigênio/farmacocinética , Atum/metabolismo , Aerobiose , Animais , Aves/anatomia & histologia , Capilares/anatomia & histologia , Mamíferos/anatomia & histologia , Mitocôndrias Musculares/metabolismo , Atum/anatomia & histologia
20.
Endosc Surg Allied Technol ; 3(4): 199-203, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8846037

RESUMO

Current medical practice deals with a variety of multimodal information (X-ray film, ultrasound, CT, MR, ECG and EEG, laboratory results, medical records, etc.) Diagnosis and treatment demand an integrated view of this information including the patient's record and history. This paper describes multimodal imaging approaches to such a system with regard to (i) user interface, (ii) data management (including access control), (iii) registration and modality matching based on reference models, and (iv) interface to the modalities.


Assuntos
Diagnóstico por Imagem , Sistemas de Informação Hospitalar , Apresentação de Dados , Sistemas de Gerenciamento de Base de Dados , Endoscopia , Humanos , Sistemas Computadorizados de Registros Médicos , Integração de Sistemas , Interface Usuário-Computador
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