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1.
J Hum Evol ; 141: 102727, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32078931

RESUMEN

Paranthropus boisei was first described in 1959 based on fossils from the Olduvai Gorge and now includes many fossils from Ethiopia to Malawi. Knowledge about its postcranial anatomy has remained elusive because, until recently, no postcranial remains could be reliably attributed to this taxon. Here, we report the first associated hand and upper limb skeleton (KNM-ER 47000) of P. boisei from 1.51 to 1.53 Ma sediments at Ileret, Kenya. While the fossils show a combination of primitive and derived traits, the overall anatomy is characterized by primitive traits that resemble those found in Australopithecus, including an oblique scapular spine, relatively long and curved ulna, lack of third metacarpal styloid process, gracile thumb metacarpal, and curved manual phalanges. Very thick cortical bone throughout the upper limb shows that P. boisei had great upper limb strength, supporting hypotheses that this species spent time climbing trees, although probably to a lesser extent than earlier australopiths. Hand anatomy shows that P. boisei, like earlier australopiths, was capable of the manual dexterity needed to create and use stone tools, but lacked the robust thumb of Homo erectus, which arguably reflects adaptations to the intensification of precision grips and tool use. KNM-ER 47000 provides conclusive evidence that early Pleistocene hominins diverged in postcranial and craniodental anatomy, supporting hypotheses of competitive displacement among these contemporaneous hominins.


Asunto(s)
Fósiles/anatomía & histología , Hominidae/anatomía & histología , Extremidad Superior/anatomía & histología , Animales , Kenia
2.
J Hum Evol ; 112: 148-161, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28760580

RESUMEN

Placing the biological adaptations of Pleistocene hominins within a well-resolved ecological framework has been a longstanding goal of paleoanthropology. This effort, however, has been challenging due to the discontinuous nature of paleoecological data spanning many important periods in hominin evolution. Sediments from the Upper Burgi (1.98-1.87 Ma), KBS (1.87-1.56 Ma) and Okote (1.56-1.38 Ma) members of the Koobi Fora Formation at East Turkana in northern Kenya document an important time interval in the evolutionary history of the hominin genera Homo and Paranthropus. Although much attention has been paid to Upper Burgi and KBS member deposits, far less is known regarding the East Turkana paleoecosystem during Okote Member times. This study pairs spatially-resolved faunal abundance data with stable isotope geochemistry from mammalian enamel to investigate landscape-scale ecosystem variability during Okote Member times. We find that during this period 1) taxa within the East Turkana large mammal community were distributed heterogeneously across space, 2) the abundance of C3 and C4 vegetation varied between East Turkana subregions, and 3) the Karari subregion, an area with abundant evidence of hominin stone tool manufacture, had significantly more C3 vegetation than regions closer to the central axis of the Turkana Basin (i.e., Ileret and Koobi Fora). These findings indicate that the East Turkana paleoecosystem during the Okote Member was highly variable across space and provided a complex adaptive landscape for Pleistocene hominins.


Asunto(s)
Ecosistema , Fósiles , Mamíferos/clasificación , Plantas/clasificación , Animales , Biodiversidad , Evolución Biológica , Sedimentos Geológicos/análisis , Hominidae , Kenia
3.
Urology ; 45(1): 142-5, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7817469

RESUMEN

We describe the course of acute renal infarction, without a demonstrable cause, in an otherwise healthy young male. Renal function was not compromised, and the infarct failed to progress. Literature on relevant diagnostic and therapeutic modalities is reviewed.


Asunto(s)
Infarto/etiología , Riñón/irrigación sanguínea , Obstrucción de la Arteria Renal/complicaciones , Enfermedad Aguda , Adulto , Embolia/complicaciones , Embolia/diagnóstico , Embolia/terapia , Humanos , Masculino , Obstrucción de la Arteria Renal/diagnóstico , Obstrucción de la Arteria Renal/terapia
4.
Digestion ; 28(2): 132-7, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6653925

RESUMEN

A sulfotransferase activity which catalyzes the transfer of sulfate group from 3'-phosphoadenosine-5'-phosphosulfate to galactosylceramide and triglucosyl monoalkylmonoacylglycerol has been demonstrated in antral and fundic mucosa of normal human stomach. With both types of mucosa maximum activity for sulfation of galactosylceramide was obtained at pH 6.8, whereas the pH optimum for sulfation of triglucosyl monoalkylmonoacylglycerol was 7.8. The reactions were stimulated by the addition of Triton X-100, Mg2+ and F1-. The sulfotransferase activity of fundic mucosa for the synthesis of sulfated glyceroglucolipid was about two times higher than that of antral mucosa, while the enzyme activity for sulfation of glycosphingolipid was similar in both areas of the stomach.


Asunto(s)
Mucosa Gástrica/enzimología , Glucolípidos/metabolismo , Lípidos/biosíntesis , Adulto , Anciano , Fluoruros/farmacología , Galactosilceramidas/metabolismo , Fundus Gástrico/enzimología , Humanos , Concentración de Iones de Hidrógeno , Magnesio/farmacología , Persona de Mediana Edad , Octoxinol , Fosfoadenosina Fosfosulfato/metabolismo , Polietilenglicoles/farmacología , Antro Pilórico/enzimología
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