RESUMO
Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau, China relies on discovering new plant fossils. The Qaidam Basin has long been regarded as an ideal 'field laboratory' to investigate the paleoclimate and paleobiological evolution of the northern Tibetan Plateau. However, fossil angiosperms from the Qaidam Basin are rare, and our knowledge of its paleovegetation is poor. Here, we report fossil leaves and fruits of Betulaceae found from the Oligocene Shangganchaigou Formation of northwestern Qaidam Basin (Huatugou area). Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus grandis. These findings, together with other reported fossil plants from the same locality, reveal a close floristic linkage between the Qaidam Basin and Europe during the Oligocene. The northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late Paleogene. This floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies, which transported moisture and provided favorable climatic conditions. Indeed, fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest, which differs from the region's modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.
RESUMO
BACKGROUND: Mammary-type myofibroblastoma (MTMF) is a rare benign extramammary soft tissue tumor with myofibroblastic differentiation. Although 160 cases of MTMF have been reported in the literature since 2001, no cases of infarction or atypical mitosis have been reported so far. Herein, we report an unusual case of MTMF in the pelvic cavity, which mimicked some malignant features, including infarction, atypical mitosis, infiltrative growth, and prominent cytologic atypia, making it difficult to ascertain whether the tumor was benign. CASE SUMMARY: A 49-year-old man complained of pain and discomfort in the right buttock for more than 4 mo and did not receive any treatment. Nuclear magnetic resonance imaging (MRI) showed a 13-cm-sized mass in his right pelvic cavity. Histologically significant differences were atypical mitosis figures and multiple necrotic foci in the tumor. In addition, smooth muscle and skeletal muscle were invaded within and at the edge of the tumor. These morphologic features are often reminiscent of malignant tumors and therefore pose a diagnostic challenge to pathologists. The tumor cells were strongly positive for both cluster of differentiation 34 and desmin, and the loss of retinoblastoma 1 shown by immunohistochemical and fluorescence in situ hybridization results confirmed the pathological diagnosis of MTMF. Currently, the patient is alive and in good condition without tumor recurrence or metastasis after 2.5 years of follow-up by telephone and MRI. CONCLUSION: The two pseudo-malignant characteristics of infarction and atypical mitosis broaden the morphological lineage of MTMF, a rare mesenchymal tumor.
RESUMO
OBJECTIVE: To study the expression of gastrin(GAS) and gastrin releasing peptide(GRP) in patients with gastric cancer and investigate the clinical significance. METHODS: The expression of GAS and GRP in sixty patients with gastric cancer was detected by using tissue chip technique and immunohistochemical methods. RESULTS: The positive rates of GAS and GRP were 30.0% and 11.7% respectively in 60 cases with gastric cancer. The positive rates of GAS and GRP were higher in moderately and poorly differentiated cancers than those in well differentiated cancer (P< 0.05). The positive rates of GAS and GRP were significantly higher in mucinous adenocarcinoma and signet-ring cell carcinoma than those in other types of gastric cancer (P< 0.05). The positive expression of GAS and GRP in gastric cancer was correlated with lymph node metastasis (P< 0.05). CONCLUSION: Tissue chip technique is a feasible,rapid,economic and accurate approach for screening clinical tissue specimens on a large scale.
