Excessive dorsiflexion (dorsal tilting) of the lunate on a lateral wrist radiograph can be an important sign of carpal injury. Lunate dorsiflexion is a well-recognized sign of an intercarpal ligamentous injury pattern known as dorsal intercalated segment instability (DISI). It is less well recognized that excessive dorsal tilting of the lunate (DISI configuration) can also be produced by displacement of a scaphoid waist fracture. Since the management and prognosis of displaced scaphoid fractures may be quite different from those for nondisplaced fractures, radiologists can make an important contribution by recognizing dorsal tilting of the lunate and appreciating that it may be an important, indirect sign of scaphoid fracture displacement, which may not be directly visualized with standard wrist radiography. In this setting, computed tomography or complex motion tomography may be helpful for further evaluation of the scaphoid fracture. 相似文献
A possible role of nitric oxide (NO) in adult neurogenesis has been suggested based on anatomical findings showing that subventricular zone (SVZ) neuroblasts are located close to NO-producing cells, and on the known antiproliferative actions of NO in many cell types.Experiments have been performed in rodents with systemic and intracerebroventricular administrations of the NO synthase (NOS) inhibitor L-NAME. NOS inhibition leads to significant increases in the number of proliferating cells in the SVZ and olfactory bulb (OB). NO exerts its cytostatic action preferentially on the cell population expressing nestin but not βIII-tubulin, which may correspond to the type C cells described in the SVZ. The negative effect of NO on SVZ cell proliferation has also been confirmed in SVZ primary cultures.An inhibition of the tyrosine kinase activity of the epidermal growth factor receptor (EGFR) is described as one of the molecular mechanisms responsible for the antiproliferative effect of NO in SVZ cells. Biochemical data supporting this conclusion has been obtained using the neuroblastoma cell line NB69, which endogenously expresses the EGFR. In these cells, the antimitotic action of NO occurs upon inhibition of the EGFR tyrosine phosphorylation, probably by a direct S-nitrosylation of the receptor.The latest published reports on NO and neurogenesis indicate that NO physiologically participates in the control of adult neurogenesis by modulating the proliferation and fate of the SVZ progenitor cells. These effects might be partially due to a direct inhibition of the EGFR by S-nitrosylation. 相似文献
Structural rearrangements involving the short arm of chromosome 12 occur in 10% of cases of childhood acute lymphoid leukemia. The translocation t(12;17)(p13;q21), an uncommon 12p abnormality, was identified in five of 2620 cases (0.2%) successfully karyotyped by the Pediatric Oncology Group or St Jude Children's Research Hospital. All five cases were classified as early pre-B; however, CD10 (common acute lymphoblastic leukemia antigen) was expressed at lower levels than other markers of B-cell lineage. Two cases also expressed the myeloid-associated antigen CD33. Leukemic cells were pseudodiploid in four cases, with an extra chromosome 21 in the fifth case. All of these patients achieved complete remission. Two relapsed during subsequent therapy, and three remain in continuous remission for greater than or equal to 20 months. 相似文献
Chagas' disease patients (CDP) develop both humoral and cellular immune
responses against the major cysteine proteinase (cruzipain) from
Trypanosoma cruzi. Here we demonstrate that complexes formed by cruzipain
and alpha 2-macroglobulin (alpha 2M) are efficiently internalized by human
monocytes, and that this process results in enhanced presentation of
cruzipain peptides to CD4+ T cells from CDP. Purified or serum alpha 2M
binds to polymorphic cruzipains, but only a fraction of the proteinases
become covalently linked. Once bound to alpha 2M, fluorescein-labeled
cruzipain (FITC-cruzipain) or [125I]cruzipain were more efficiently
internalized by normal peripheral blood mononuclear cells (PBMC) or
monocytes; this effect was abolished by (I) pre-treating the cells with
receptor-associated protein (rRAP), a known antagonist the of alpha 2M
receptor (alpha 2MR/LRP), and (II) inactivating [125I]cruzipain's active
site prior to the reaction with alpha 2M, indicating that the exposure of
receptor binding sites on alpha 2M complexes required bait region cleavage.
We then sought to determine if the alpha 2MR/LRP-dependent uptake of alpha
2M:cruzipain by monocytes resulted in increased CD4+ T cell responses of
PBMC-CDP (n = 13). These effects were only revealed after depletion of
CD19+ B lymphocytes from PBMC-CDP; the threshold of T cell stimulation was
far lower in cultures stimulated with alpha 2M:cruzipain, as compared to
antigen alone. Myocardial specimens from CDP with chronic myocardiopathy
(three necropsies) were analyzed by immunohistochemistry with mAb
anti-cruzipain or anti-alpha 2MR/LRP (CD81+). Extracellular depots of
cruzipain were localized amidst inflammatory mononuclear infiltrates, part
of which contained CD91+ macrophage-like cells. Ongoing studies should
clarify if T. cruzi cysteinyl proteinases play a role in the pathogenesis
of Chagas' heart disease.
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Collapsing pes plano valgus deformity and pes cavus deformity have been identified and treated for many years. Recently, a combination of these deformities has been recognized occurring simultaneously. This multiplanar deformity is known as the cavo-valgus foot. Treatment of this foot type requires a firm understanding of planal dominance. The authors present a case report on this subject. 相似文献
Six patients with extremity osteosarcoma initially underwent successful treatment of the primary tumor with four to seven courses of intraarterial cis-diamminedichloroplatin-II (IA-CDP; 100 to 150 mg/m2/course). The primary tumors in two patients were then extirpated by limb salvage. However, a local soft tissue recurrence occurred in both patients several months later. The other four patients refused surgical intervention and later also developed local bony recurrences. Reinstatement of three to five courses of IA-CDP in all six patients induced a complete response in five. The local recurrences (bony and soft tissue) in all six patients were excised. This included limb-salvage procedures in three patients. Additional postoperative chemotherapy was administered. Four patients remain alive and continuously free of disease 3.5+ to 4.5+ years after retreatment with IA-CDP. 相似文献
Polymethoxylated flavones (PMFs) have been recognized to inhibit colorectal cancer proliferation through various mechanisms, however most of these studies have been performed on cells grown as monolayers that present limitations in mimicking the 3D tumor architecture and microenvironment. The main aim of this study was to investigate the anticancer potential of an orange peel extract (OPE) enriched in PMFs in a 3D cell model of colorectal cancer. The OPE was developed by supercritical fluid extraction and the anticancer effect was evaluated in HT29 spheroids cultures in a stirred-tank based system.
Results showed that OPE inhibited cell proliferation, induced cell cycle arrest (G2/M phase), promoted apoptosis, and reduced ALDH+ population on HT29 spheroids. The antiproliferative activity was significantly lower than that obtained for 2D model (EC50 value of 0.43 ± 0.02 mg/mL) and this effect was dependent on diameter and cell composition/phenotype of spheroids derived from different culture days (day 3 – 0.53 ± 0.05 mg/mL; day 5 – 0.55 ± 0.03 mg/mL; day 7 – 1.24 ± 0.15 mg/mL). HT29 spheroids collected at day 7 presented typical characteristics of in vivo solid tumors including a necrotic/apoptotic core, hypoxia regions, presence of cancer stem cells, and a less differentiated invasive front. Nobiletin, sinesentin, and tangeretin were identified as the main compounds responsible for the anticancer activity. 相似文献