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1.
J Hum Evol ; 40(5): 393-409, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11322801

RESUMO

A new genus and species of medium-sized fossil primate, Myanmarpithecus yarshensis, is described from the lastest middle Eocene sediments of Pondaung, central Myanmar (Burma). The specimens consist of right maxillary fragments with P(4)-M(3)and a left mandibular corpus with C-P(3)and M(2-3). To date, three purported anthropoids have been discovered from the Pondaung Formation: Pondaungia and Amphipithecus (Amphipithecidae) and Bahinia (Eosimiidae). Myanmarpithecus differs from these other Pondaung primates in having cingular hypocones on upper molars and in lacking paraconids on M(2-3). Although Myanmarpithecus resembles some utahiin omomyines in superficial aspects of the morphology of M(2-3)(i.e., mesiodistally compressed molar trigonid and enamel crenulation), the morphological analysis of upper molars and lower premolars indicates that it is neither an omomyoid nor an adapoid but is more derived than fossil prosimians (such as adapoids, omomyoids, and tarsiers) and more anthropoid-like. On the other hand, it is more primitive (prosimian-like) than early anthropoids from the late Eocene/early Oligocene of the Fayum, Egypt. Myanmarpithecus is likely to be an early, primitive anthropoid ("protoanthropoid").


Assuntos
Fósseis , Haplorrinos/classificação , Animais , Antropologia Física , Egito , Mandíbula/fisiologia , Microscopia Eletrônica de Varredura , Dente Molar/fisiologia , Mianmar , Paleontologia/métodos
2.
Am J Phys Anthropol ; 111(2): 263-81, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10640951

RESUMO

Branisella boliviana, from the Late Oligocene of Salla, Bolivia, is the oldest fossil platyrrhine monkey discovered. To date, several fossil specimens of Branisella have been obtained, but most of them are fragmentary dentitions, so the animals craniodental morphology is still obscure. During the 1996 field season a pair of upper and lower jaw fragments and another nearly complete mandible were recovered. These new fossil materials reveal the following morphological features in Branisella: 1) P(2) is much smaller than P(3,4), whereas P(2) is relatively small but probably sexually dimorphic; 2) the zygomatic arch protrudes smoothly posterolaterally from the maxillary bone, as in extant Callicebus; 3) the mandibular arcade is nearly V-shaped and the symphysial angle, which is formed by the horizontal plane and the anterior face of mandibular symphysis, is about 40 degrees, i.e., it neither leans as far anteriorly as in callitrichines nor does it stand as vertically as Cebus; 4) upper and lower molars wore down rapidly in life, suggesting a herbivorous diet and the possibility of terrestriality; and 5) dental eruptive sequence is the same as in extant Aotus. As a whole, the dentition of Branisella is very similar to that of Proteopithecus from the Late Eocene of Fayum, Egypt, except in the lower canine morphology, suggesting a close phyletic relationship between them. The origin and early diversification of platyrrhine monkeys might have occurred on the African continent before crossing the Atlantic Ocean.


Assuntos
Evolução Biológica , Cebidae/anatomia & histologia , Dentição , Filogenia , Animais , Biometria , Cebidae/genética , Dieta , Fósseis
3.
Biol Pharm Bull ; 22(11): 1202-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10598028

RESUMO

The photoproducts produced by irradiating 8-methoxypsoralen (8-MOP) in the presence of spermine (Spm) were fractionated using gel filtration chromatography (GFC) on a Sephadex G-25 column. As a result, two bands which were characterized by the effects on hyaluronidase activity were obtained. The first band strongly activated the hyaluronidase, but a second band did not exhibit any effect on the enzyme activity. The first and second bands contained photoproducts with molecular weights (MW)>2700 and MW<728, respectively, determined by the GFC method. The photoproducts, 8-MOP-Spm-P(GFC) obtained from the first band, but not the photoproducts with lower MW from the second band, showed enzyme activating action. 8-MOP-Spm-P(GFC) induced paw edema, which was stronger in the first phase than the second one in rats, differing from that induced by carrageenin. This photoproduct was a substance with lower cell toxicity because it did not cause hemolysis on red blood cells or the release of lactic dehydrogenase from mast cells in rats. The effects of various drugs on 8-MOP-Spm-P(GFC)-induced edema were investigated. As a result, edema formation was inhibited by drugs with an anti-histaminic action, such as alimemazine, dl-chlorpheniramine, promethazine, ketotifen and azelastine, and with anti-serotonin action such as cyproheptadine. On the other hand, tranilast did not show significant inhibition and indomethacin showed a tendency to increase its formation. These results suggested that 8-MOP-Spm-P(GFC) is a new inflammatory substance and is very useful as an agent to develop new anti-inflammatory drugs without cyclooxygenase inhibitory action.


Assuntos
Edema/induzido quimicamente , Edema/tratamento farmacológico , Metoxaleno/toxicidade , Espermina/toxicidade , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Hemólise/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos/farmacologia , Hialuronoglucosaminidase/química , Concentração de Íons de Hidrogênio , L-Lactato Desidrogenase/metabolismo , Masculino , Metoxaleno/química , Peso Molecular , Ratos , Ratos Sprague-Dawley , Espermina/química
4.
Biol Pharm Bull ; 16(6): 576-8, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7689893

RESUMO

To confirm the inflammatory activity of polymeric photoproducts (CPZ-polymers) of chlorpromazine (CPZ), which were obtained by gel filtration of a UV-pre-irradiated CPZ aqueous solution, the histamine release from rat peritoneal exudate cells was studied and the paw-inflammation in mice induced by these CPZ-polymers was examined. CPZ-polymers induced a dose-dependent histamine release at concentrations of 1, 3 and 10 mg/ml. This effect was approximately one-tenth of that of compound 48/80. Furthermore, CPZ-polymers markedly induced lasting paw-edema in a dose-dependent manner, the swellings remaining for at least 96 h. When intraperitoneally injected into mice, CPZ-polymers induced a significant elevation of histamine release in the peritoneal cavity 0.5 h after the injection, compared with a control group. The histamine levels in the cavities returned to normal within the next 0.5 h, and remained normal for at least 23 h, indicating that histamine release may be caused only in the early stages of CPZ-polymer-induced inflammation. The inflammatory activity of the CPZ-polymers suggests that they are inflammatory substances formed from CPZ by UV-irradiation.


Assuntos
Clorpromazina/toxicidade , Inflamação/induzido quimicamente , Animais , Clorpromazina/análogos & derivados , Clorpromazina/efeitos da radiação , Edema/induzido quimicamente , Liberação de Histamina/efeitos dos fármacos , Técnicas In Vitro , Inflamação/patologia , L-Lactato Desidrogenase/metabolismo , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Fotoquímica , Ratos , Ratos Sprague-Dawley , Raios Ultravioleta
5.
Okajimas Folia Anat Jpn ; 68(6): 377-91, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1603527

RESUMO

Two cases of Adachi-Williams-Nakagawa type N (Krause's type II-2-B) right-sided arch of the aorta were observed gross anatomically. We discovered the first in a 67-year-old female corpse during dissection practice. The second was found in an old male patient through radiography. After his death at 87 years, angiography revealed the anomaly to be of type N. Case 2 (and case 1 after the discovery of the anomaly) were dissected outside of regular dissection practice. Neither belonged to the "circumflexus" type and in each case the ligamentum arteriosum was located on the left, forming a vascular ring. However, only case 1 exhibited marked constriction of the esophagus, explaining the dysphagia that she had suffered. This deviation was evidently caused by projection of the aortic diverticulum of case 1 in front of the vertebral column (since the origin of the descending aorta was located at a more antero-medial position in case 1 than in case 2) and narrowness of the vascular ring of case 1. On both sides in both cases, the second posterior intercostal arteries were branches of the thoracic aorta. This indicated that the high position of the arch of the aorta in both cases (the uppermost point was at the level between Th1 and Th2) is an anomaly, being not limited only to the arch of the aorta. All bronchial arteries originated from the thoracic aorta. These have not been described in association with examples of right-sided arch of the aorta, and were therefore compared against a mirror image of the normal aorta described by Kasai. However, some discrepancies were still noted. Among the veins, the left brachiocephalic vein of case 2 was partially occluded, forming collateral circulation behind the ascending aorta. In both cases, the thoracic duct ascended on the left of the thoracic aorta, passed behind and then above the left subclavian artery, and joined the left angulus venosus. In addition, the azygos vein, recurrent laryngeal nerve, and cardiac nerves are described.


Assuntos
Aorta Torácica/anormalidades , Artéria Subclávia/anormalidades , Idoso , Aorta Torácica/patologia , Veias Braquiocefálicas/anormalidades , Artérias Brônquicas/anormalidades , Feminino , Coração/inervação , Humanos , Masculino , Artéria Subclávia/patologia , Ducto Torácico/anormalidades
6.
Photodermatol Photoimmunol Photomed ; 8(6): 229-31, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1823146

RESUMO

Ultraviolet radiation of 8-methoxypsoralen (8-MOP) in the presence of various polyamines resulted in stable photoproducts that were very soluble in water and showed hyaluronidase-activating properties. Among them, the photoproducts obtained from the reaction systems of 8-MOP-spermine and 8-MOP-spermidine markedly activated hyaluronidase. The enzyme activity was not affected by 8-MOP alone and the photoproduct of 8-MOP (8-MOP-P). From these facts, it was suggested that the photoproducts with hyaluronidase-activating properties might play an important role in the onset of 8-MOP-induced photosensitivity.


Assuntos
Hialuronoglucosaminidase/química , Metoxaleno/efeitos da radiação , Poliaminas/efeitos da radiação , Animais , Bovinos , Cromatografia em Camada Fina , Ativação Enzimática/efeitos dos fármacos , Metoxaleno/farmacologia , Poliaminas/farmacologia , Raios Ultravioleta
7.
Photodermatol ; 4(5): 240-5, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3697347

RESUMO

A pre-irradiated chlorpromazine (CPZ) in pH 7.2 and aqueous solutions activated hyaluronidase, and it showed the enzyme-activating action even after 7 days of irradiation. This indicates that the stable photoproducts of CPZ activated the enzyme. But promazine and CPZ-5-sulfoxide, which are photoproducts of CPZ, did not activate the enzyme in the presence and absence of UVA. The dimer and higher molecular weight (MW) products of CPZ that were obtained by treating the pre-irradiated CPZ solution with gel permeation chromatography showed the hyaluronidase by activating action without UVA. In addition, photoactivation of hyaluronidase by CPZ was inhibited by radical quenchers. This suggested that the photoproducts with enzyme-activating action were produced via some radicals. On the basis of these findings, a possible mechanism for photoactivation of hyaluronidase by CPZ was proposed.


Assuntos
Clorpromazina/farmacologia , Hialuronoglucosaminidase/metabolismo , Luz , Radiossensibilizantes/farmacologia , Animais , Fenômenos Biomecânicos , Bovinos , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/efeitos da radiação
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