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Neuromyelitis optica (NMO) is an autoimmune disease targeting aquaporin 4 (AQP4), localized mainly at the astrocytic foot processes. Loss of AQP4 and glial fibrillary acidic protein (GFAP) was reported, but the pathological significance of astrocytopathy is still controversial. Here we show that active lesions in NMO display a wide spectrum of pathology even within a single tissue block of an individual patient. We have distinguished six different lesion types. The first reflects complement deposition at the surface of astrocytes, associated with granulocyte infiltration and astrocyte necrosis and followed by demyelination, global tissue destruction and the formation of cystic, necrotic lesions (lesion type 2). Such destructive lesions lead to Wallerian degeneration in lesion-related tracts (lesion type 3). Around active NMO lesions AQP4 may selectively be lost in the absence of aquaporin 1 (AQP1) loss or other structural damage (lesion type 4). Another pattern is characterized by clasmatodendrosis of astrocytes, defined by cytoplasmic swelling and vacuolation, beading and dissolution of their processes and nuclear alterations resembling apoptosis, which was associated with internalization of AQP4 and AQP1 and astrocyte apoptosis in the absence of complement activation. Such lesions give rise to extensive astrocyte loss, which may occur in part in the absence of any other tissue injury, such as demyelination or axonal degeneration (lesion type 5). Finally, lesions with a variable degree of astrocyte clasmatodendrosis are found, which show plaque-like primary demyelination that is associated with oligodendrocyte apoptosis, but with preservation of axons (lesion type 6). In active multiple sclerosis (MS) lesions astrocytes reveal changes of reactive protoplasmatic or fibrillary gliosis. Only in a subset of lesions, in patients with aggressive disease, loss of AQP4 is observed in the initial stage of their formation, which is associated with retraction of astrocyte processes in the absence of complement deposition, granulocyte infiltration or loss of AQP1 or astrocytes. Our data underline the primary assault of astrocytes in NMO lesions, but also indicate that different mechanisms of tissue injury operate in parallel in the same patient and even within the same lesion.  相似文献   
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European Journal of Orthopaedic Surgery & Traumatology - Combined anteversion (CA) technique (stem-first procedure) is generally accepted as the optimal technique to attain an appropriate CA...  相似文献   
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We report a rare case of disseminated carcinomatosis of the bone marrow from rectal cancer with disseminated intravascular coagulation (DIC). A 65-year-old man was admitted with melena and low back pain at rest. X-ray examination showed rectal cancer with multiple bone metastases. Laboratory examination showed severe anemia and DIC. Histologic examination showed disseminated carcinomatosis of the bone marrow. The DIC was considered to be caused by disseminated carcinomatosis of the bone marrow from rectal cancer, and we immediately started treatment with anti-DIC therapy and anticancer chemotherapy with the modified FOLFOX6 regimen (mFOLFOX6). After some response to therapy, the patient''s general condition deteriorated, and he died 128 days after admission. This is the first English report showing disseminated carcinomatosis of the bone marrow from colorectal cancer treated with mFOLFOX6.Key words: Bone marrow neoplasms, Rectal neoplasms, Disseminated intravascular coagulationBone metastases diffusely invading the bone marrow with disseminated intravascular coagulation (DIC) and microangiopathic hemolytic anemia (MHA) tend to accompany solid tumors; this condition is called disseminated carcinomatosis of the bone marrow,1 and it is associated with an extremely poor prognosis. Among solid tumors, DIC is most commonly associated with breast cancer, prostate cancer, and lung cancer2,3; carcinomatosis arising from colorectal cancer is rare.Herein we report on a patient with disseminated carcinomatosis of the bone marrow with rectal cancer who developed acute DIC and was treated with a modified FOLFOX6 regimen (mFOLFOX6). We also review 11 similar previously reported cases.410  相似文献   
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Although it is well known that the maternal prepregnancy BMI is a strong contributor to fetal growth, our results showed that a low postload glucose level, although within normal range, independent of maternal BMI was strongly associated with an increased risk of low birth weight births among Japanese mothers.  相似文献   
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Therapeutic angiogenesis is a promising approach to treat ischemic skin flaps. We delivered basic fibroblast growth factor (bFGF) to the recipient bed of a rat dorsal skin flap by a drug delivery system with acidic gelatin hydrogel microspheres (AGHMs), and assessed augmentation of neovascularization and flap viability. An axial skin flap was elevated on the back of male Sprague–Dawley rats, and bFGF solution or bFGF-impregnated AGHMs were injected into the recipient bed. The dose of bFGF in the bFGF solution was set to 15 (Sol-15 group), 50 (Sol-50 group), or 150 μg (Sol-150 group). Correspondingly, 2 mg AGHMs were impregnated with 15 (AGHM-15 group), 50 (AGHM-50 group), or 150 μg (AGHM-150 group) bFGF. Other groups of animals received phosphate-buffered saline (Sol-Cont group) or phosphate-buffered saline-impregnated AGHMs (AGHM-Cont group) as controls. Seven days later, analyses of the area of necrosis, microangiographic findings, and histological findings in the flap were carried out. The area of necrosis in the AGHM-150 group was significantly smaller than that in the other groups. Microangiographic and histological analyses showed that neovascularization of the ischemic skin flap significantly increased in the AGHM-150 group as compared with the Sol-150 group and the AGHM-Cont group. These findings suggest that continuous delivery of bFGF to the recipient bed by bFGF-impregnated AGHMs enhances the viability of an ischemic skin flap.  相似文献   
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