The hypothesis that greater safety from cavitation by airseeding through inter-vessel pits comes at the cost of less porous pit membranes with greater flow resistance was tested . Sixteen vessel-bearing species were compared: 11 from the Rosaceae, four from other angiosperm families, and one fern. Unexpectedly, there was no relationship between pit resistance (and hence the prevailing membrane porosity) and cavitation pressure. There was, however, an inverse relationship between pit area per vessel and vulnerability to cavitation ( r 2 = = = = 0.75). This suggests that cavitation is caused by the rare largest membrane pore per vessel, the average size of which increases with total pit area per vessel. If safety from cavitation constrains pit membrane surface area, it also limits vessel surface area and the minimum vessel resistivity. This trade-off was consistent with an approximately three-fold increase in vessel resistivity with cavitation pressure dropping from ----0.8 to ----6.6 MPa. The trade-off was compensated for by a reduction in the percentage of vessel wall pitted: from 10-16% in vulnerable species to 2-4% in resistant species. Across species, endwall pitting accounted for 53 ± ± ± ± 3% of the total xylem resistivity. This corresponded to vessels achieving on average 94 ± ± ± ± 2% of their maximum possible conductivity if vessel surface area is constrained.
We performed whole transcriptome analysis of osteosarcoma bone samples. Initially, we sequenced total RNA from 36 fresh-frozen samples (18 tumoral bone samples and 18 non-tumoral paired samples) matching in pairs for each osteosarcoma patient. We also performed independent gene expression analysis of formalin-fixed paraffin-embedded samples to verify the RNAseq results. Formalin-fixed paraffin-embedded samples allowed us to analyze the effect of chemotherapy. Data were analyzed with DESeq2, edgeR and Reactome packages of R. We found 5365 genes expressed differentially between the normal bone and osteosarcoma tissues with an FDR below 0.05, of which 3399 genes were upregulated and 1966 were downregulated. Among those genes, BTNL9, MMP14, ABCA10, ACACB, COL11A1, and PKM2 were expressed differentially with the highest significance between tumor and normal bone. Functional annotation with the reactome identified significant changes in the pathways related to the extracellular matrix degradation and collagen biosynthesis. It was suggested that chemotherapy may induce the modification of ECM with important collagen biosynthesis. Taken together, our results indicate that changes in the degradation of extracellular matrix seem to be an important mechanism of osteosarcoma and efficient chemotherapy induces the genes related to bone formation. Impact statement Osteosarcoma is a rare disease but it is of interest to many scientists all over the world because the current standard treatment still has poor results. We sequenced total RNA from 36 fresh-frozen paired samples (18 tumoral bone samples and 18 non-tumoral paired samples) from osteosarcoma patients. We found that differences in the gene expressions between the normal and affected bones reflected the changes in the regulation of the degradation of collagen and extracellular matrix. We believe that these findings contribute to the understanding of OS and suggest ideas for further studies.
Osteosarcoma (OS) is a rare malignant bone tumor. It affects mostly young persons and has poor outcome with the present treatment. No improvement was observed since the introduction of chemotherapy. The better understanding of osteosarcoma development could indicate better management strategy. Repetitive DNA elements were found to play a role in cancer mechanism especially in epithelial tumors but not yet analyzed in osteosarcoma. We conducted the study to analyse the expression profile of repetitive elements (RE) in osteosarcoma.Methods: Fresh bone paired (tumor and normal bone) samples were obtained from excised parts of tumors of 18 patients with osteosarcoma. We performed sequencing of RNA extracted from 36 samples (18 tumor tissues and 18 normal bone for controls), mapped raw reads to the human genome and identified the REs. EdgeR package was used to analyse the difference in expression of REs between osteosarcoma and normal bone.Results: 82 REs were found differentially expressed (FDR < 0.05) between osteosarcoma and normal bone. Out of all significantly changed REs, 35 were upregulated and 47 were downregulated. HERVs (THE1C-int, LTR5, MER57F and MER87B) and satellite elements (HSATII, ALR-alpha) were the most significantly differential expressed elements between osteosarcoma and normal tissues. These results suggest significant impact of REs in the osteosarcoma. The role of REs should be further studied to understand the mechanism they have in the genesis of osteosarcoma.
T reaTmenT management strategies for pituitary macroadenomas depend on numerous factors that guide the determination of medical management, surgical approach, and/or adjuvant therapeutic options. Maximal resection and adequate decompression of the neurological structures is the paradigm of care for symptomatic pituitary macroadenomas, with the exception of medically responsive prolactinomas.Since its inception by Schloffer in 1907 and then refinement and popularization by Hirsch, Guiot, and Hardy, the transsphenoidal approach has become the preferred route to the sella because of its relative safety profile. 9,14,16,17 The transcranial route still plays an important role in providing access to the sella in 1% to 4% of pituitary macroadenomas where direct visualization and accessibility via the transsphenoidal approach are limited. 38A transcranial approach should be considered in the surgical management of pituitary adenomas that display constriction at the diaphragma sellae, parasellar extension or inaccessible suprasellar extension off the midline, tumors of fibrous consistency with large suprasellar extension, and in patients with an active sinus infection or a coexisting adjacent aneurysm. Other cases that should be approached transcranially include those patients with ectatic intrasellar carotid arteries, 40 retrosellar extension, brain invasion with edema, involvement or vasospasm of the arteries of the circle of Willis, or encasement of the optic apparatus or invasion of the optic foramina. obJective Oculomotor cistern extension of pituitary adenomas is an overlooked feature within the literature. In this study, 7 cases of pituitary macroadenoma with oculomotor cistern extension and tracking are highlighted, and the implications of surgical and medical management are discussed. methods The records of patients diagnosed with pituitary macroadenomas who underwent resection and in whom preoperative pituitary protocol MRI scans were available for review were retrospectively reviewed. The patient and tumor characteristics were reviewed along with the operative outcomes and complications. results Seven patients (4.1%) with oculomotor cistern extension and tracking were identified in a cohort of 170 patients with pituitary macroadenoma. The most common presenting symptoms were visual deficit (6 patients; 86%), apoplexy (3 patients; 43%), and oculomotor nerve palsy (3 patients; 43%). Lone oculomotor nerve palsy was seen in 2 patients without apoplexy and 1 patient with an apoplectic event. Gross-total resection was achieved via a microscopic endonasal transsphenoidal approach with or without endoscopic aid to the sella in 14%, near-total resection in 29%, and subtotal resection in 57% of patients in the data set. coNclusioNs Pituitary adenoma extension along the oculomotor cistern is uncommon; however, preoperatively recognizing such extension should play an important role in the surgeon's operative considerations and postoperative clinical management because this extension can limit gross-total resection using t...
Postoperative hepatic lymphorrhea is extremely rare and there is no standard treatment for this condition. We report the cases of 3 men, 32-, 56-, and 37-year-old, with postoperative hepatic lymphorrhea, which was refractory to conservative treatment. Transhepatic lymphangiography allowed locating the lymphatic leak and treating it with hepatic lymphatic vessels injection of foam sclerotic agent. This technique seems efficient and safe.
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