RESUMO
Previously, Olduvai Bed I excavations revealed Oldowan assemblages <1.85 Ma, mainly in the eastern gorge. New western gorge excavations locate a much older â¼2.0 Ma assemblage between the Coarse Feldspar Crystal Tuff (â¼2.015 Ma) and Tuff IA (â¼1.98 Ma) of Lower Bed I, predating the oldest eastern gorge DK assemblage below Tuff IB by â¼150 kyr. We characterize this newly discovered fossil and artifact assemblage, adding information on landscape and hominin resource use during the â¼2.3-2.0 Ma period, scarce in Oldowan sites. Assemblage lithics and bones, lithofacies boundaries, and phytolith samples were surveyed and mapped. Sedimentological facies analysis, tephrostratigraphic and sequence stratigraphic principles were applied to reconstruct paleoenvironments and sedimentary processes of sandy claystone (lake), sandstone (fluvial), and sandy diamictite (debris flow) as principal lithofacies. Artifacts, sized, weighed, categorized, were examined for petrography, retouch, and flake scar size. Taxonomic classifications and taphonomic descriptions of faunal remains were made, and phytoliths were categorized based on reference collections. Lithics are dominantly quartzite, mainly debitage and less frequently simple cores, retouched pieces, and percussors. Well-rounded spheroids and retouched flakes are rare. Identifiable taxa, Ceratotherium cf. simum (white rhinoceros) and Equus cf. oldowayensis (extinct zebra), accord with nearby open savanna grasslands, inferred from C3 grass, mixed and/or alternating with C4 grass-dominated phytolith assemblages. Palms, sedges, and dicots were also identified from phytoliths. Diatoms and sponge spicules imply nearby freshwater. The assemblage accumulated at the toe of a Ngorongoro Volcano-sourced fan-delta apron of stacked debris flows, fluvials, and tuffs, preserving fossil tree stumps and wooded grassland phytoliths farther upfan. It formed after the climax of Ngorongoro volcanic activity during a Paleolake Olduvai lowstand and was then buried and preserved by lacustrine clays, marking the first of two lake transgressions, signifying wetter climates. Orbital precessional lake cycles were superposed upon multimillennial (â¼4.9 kyr) lake fluctuations.
Assuntos
Evolução Cultural , Meio Ambiente , Hominidae , Tecnologia , Animais , Arqueologia , Paleontologia , TanzâniaRESUMO
We herein report a relatively rare case of a woman in her 30s with an incidental lung finding. She subsequently underwent resection for what was considered to be a solitary fibrous tumour of the pleura (SFTP). SFTPs are rare, slow-growing neoplasms from mesenchymal origin. These tumours are histologically characterised by proliferation of bland-looking spindled cells, arranged in a patternless pattern, with hypocellular and hypercellular areas set in a hyalinised stroma. Complete en bloc surgical excision (with margin negativity) is the treatment of choice for both benign and malignant SFTPs. Due to the possibility of local recurrence with benign and malignant SFTPs, clinical and radiological follow-up is recommended.
Assuntos
Tumor Fibroso Solitário Pleural , Feminino , Humanos , Achados Incidentais , Tumor Fibroso Solitário Pleural/diagnóstico por imagem , Tumor Fibroso Solitário Pleural/cirurgia , Tomografia Computadorizada por Raios XRESUMO
We present the case of a 33-year-old pregnant woman with an abnormal liver profile secondary to liver metastases from colon cancer. The patient presented in her third trimester with non-specific symptoms. Blood tests revealed a cholestatic liver picture, initially attributed to prurigo gravidarum. However, following a normal vaginal delivery, her symptoms persisted and the liver profile failed to return to baseline. This led to further investigations including a CT scan of the abdomen-revealing a transverse colonic tumour with extensive liver involvement. Biopsy of the liver confirmed an adenocarcinoma of colonic origin, and subsequently the patient underwent a right hemicolectomy followed by systemic chemotherapy.
Assuntos
Adenocarcinoma , Neoplasias do Colo , Abdome/patologia , Adenocarcinoma/diagnóstico , Adulto , Colectomia , Neoplasias do Colo/patologia , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , GravidezRESUMO
We present a unique case of a 41-year-old man with an anterior mediastinal mass and a pulmonary nodule, found incidentally on a thoracic CT. Further evaluation with an MRI revealed a thymic cyst which was multiloculated with several septations. Biopsy of the pulmonary nodule was performed and histology was consistent with a solitary fibrous tumour (SFT), on the benign spectrum. Both lesions were successfully resected simultaneously via a median sternotomy approach. Final full histological diagnoses confirmed a multiloculated thymic cyst and a completely excised SFT.