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51.
Tremendous progress in recent computer-controlled systems for fluorescence and laser-confocal microscopy has provided us with powerful tools to visualize and analyze molecular events in the cells. Various fluorescent staining and labeling techniques have also been developed to be used with these powerful instruments. Fluorescent proteins such as green fluorescent protein (GFP) allow us to directly label particular proteins of interest in living cells. This technique has been extended over a large area of cell biology, and a variety of fluorescent protein-derived techniques have been developed to visualize the functions and conditions of the molecules within living cells. In this review, we summarize the techniques for fluorescent staining and labeling for recent fluorescence microscopy.  相似文献   
52.
Rutaecarpine is a major alkaloid isolated from Evodia rutaecarpa. Here, we investigated the effects of rutaecarpine on osteoclast differentiation induced by macrophage colony stimulating factor (M‐CSF) and receptor activator of nuclear factor κ‐B ligand (RANKL) in bone marrow‐derived macrophages (BMMs). Treatment with rutaecarpine significantly inhibited osteoclastogenesis and prevented bone resorption of BMM‐derived osteoclasts. Mechanistically, rutaecarpine decreased the protein level of nuclear factor of activated T cells cytoplasmic‐1 (NFATc1) and the phosphorylation of other signalling pathways during the osteoclast differentiation. Thus, rutaecarpine may be useful as a therapeutic agent for the treatment of bone diseases.  相似文献   
53.
Forward dislocation of the temporomandibular joint commonly can be easily diagnosed and successfully reduced by manual repositioning. In this report, we discuss a rare case of prolonged temporomandibular dislocation that had persisted for more than 20 years because the otolaryngologist and dentist had missed the dislocation. This patient underwent open reduction and mandibular joint plasty with preoperative orthodontic therapy. It is possible that strong pain and mouth-closing disability may gradually remit and only deviated mandibular prognathism like malocclusion may persist. Therefore, abnormal occlusion warrants careful attention to temporomandibular joint dislocation.  相似文献   
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We report a case of lung infection due to Mycobacterium abscessus (M. abscessus), complicated with primary macroamylasemia. A 76-year-old man was admitted to our hospital in August 2002 because of bloody sputum and an abnormal shadow found on chest radiography. The patient had had pulmonary tuberculosis from 1998 to 2000. He was found to be antacid bacillus-positive (Gaffky 5) on examination of the sputum in August 2002, but after hospitalization was negative for tuberculosis bacillus on sputum examination by the PCR method. We had suspected the presence of non-tuberculous mycobacterial disease since the patient's admission, and had started a regime of three drugs: clarithromycin, rifampicin, and ethambutol. The bacteria were identified as M. abscessus in a later sputum culture examination. It was noticed that the blood amylase level was high, and the disease was diagnosed as primary macroamylasemia. Such a case of lung infection due to M. abscessus complicated with macroamylasemia has rarely been reported in Japan.  相似文献   
57.
Inflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha) have been implicated in atherogenesis. However, the precise role of TNF-alpha in atherogenesis is still unclear. To examine the effect of TNF-alpha on atherogenesis, we generated compound-deficient mice in apolipoprotein E (apoE) and TNF-alpha (apoE-/-/TNF-alpha-/-) and compared them with apoE-/- mice. Although serum total cholesterol levels were markedly elevated in both apoE-/-/TNF-alpha-/- and apoE-/- mice compared to wild-type mice, no differences were observed between apoE-/-/TNF-alpha-/- and apoE-/- mice. The atherosclerotic plaque area in the aortic luminal surface of apoE-/-/TNF-alpha-/- mice (n=8, 3.1+/-0.4%) was significantly smaller than that of apoE-/- mice (n=7, 4.7+/-0.4%, p<0.001) despite the lack of difference in serum cholesterol levels. The atherosclerotic lesion size in the aortic sinus of apoE-/-/TNF-alpha-/- mice (n=10, 5.1+/-0.3 x 10(5)microm(2)) was also significantly smaller than that of apoE-/- mice (n=11, 7.0+/-0.3 x 10(5)microm(2), p<0.0001). RT-PCR analysis indicated that the expression levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) were significantly higher in apoE-/- than apoE-/-/TNF-alpha-/- mice. Macrophages from apoE(-/-) mice showed higher uptake level of oxidized LDL and increased expression level of scavenger receptor class A (SRA) compared to those from apoE-/-/TNF-alpha-/- mice. These results indicate that TNF-alpha plays an atherogenic role by upregulating the expressions of ICAM-1, VCAM-1 and MCP-1 in the vascular wall, and by inducing SRA expression and oxidized LDL uptake in macrophages.  相似文献   
58.
Background

Patients with aneurysmal subarachnoid hemorrhage (SAH) typically develop appetite loss. However, the mechanisms regulating appetite are not understood. Ghrelin and leptin, both of which signal nutritional status and energy storage levels to the hypothalamus, are essential elements of the appetite system. Thus, the goal of this study was to investigate the relationship between appetite and ghrelin and leptin concentrations in patients with SAH.

Methods

Blood plasma or serum profiles and appetite status were measured in 19 patients with SAH who underwent aneurysmal clipping within 48 hours of SAH onset. Appetite status was measured using dietary oral calorie intake. All outcome variables were measured at an early (day 3) and late (day 8) time point after SAH onset (day 0).

Results

Of the 19 patients studied, 6 (31.6%) showed lower dietary oral calorie intake at the late time point than at the early time point. In these patients with appetite loss, plasma hemoglobin (P < 0.02), albumin (P < 0.01), glucose (P < 0.01), plasma insulin (P < 0.04), and serum ghrelin (P < 0.03) concentrations were lower at the late time point than at the early time point. Serum leptin was higher at the late time point than at the early time point (P < 0.02).

Conclusion

In SAH patients, appetite loss may be induced by lower serum ghrelin and higher serum leptin concentrations resulting from high plasma glucose and insulin levels due to a catecholamine surge following SAH.  相似文献   

59.
Cryptococcal meningitis is rarely complicated by immune‐mediated leukoencephalopathy, but the precise pathomechanism is uncertain. A 72‐year‐old Japanese man treated with prednisolone for Sweet disease developed a subacute progression of meningitis, which was considered as neuro‐Sweet disease. A treatment by methylprednisolone rapidly improved CSF findings with a remarkable decrease in lymphocyte numbers in the blood, but the patient's consciousness still worsened after the cessation of the treatment. The patient developed cryptococcal meningitis and MRI showed abnormal intensities predominantly in the cerebral deep white matter along with the recovery of lymphocyte numbers in the blood, which resulted in death. A postmortem examination of the brain revealed degenerative lesions, especially at the cerebral white matter and cortex adjacent to the leptomeninges abundantly infiltrated by Cryptococcus neoformans. In the affected cerebral deep white matter, perivascular infiltration of lymphocytes was prominent in coexistence with reactive astrocytes and vascular proliferation, but these findings were not observed in the subcortical and cortical lesions. Cryptococcus neoformans was not present within the brain parenchyma. This is the first report of a case suggesting that cryptococcal meningitis can accompany lymphocytic inflammation predominantly in cerebral deep white matter as a possible manifestation of immune reconstitution inflammatory syndrome.  相似文献   
60.

Purpose

Although distraction osteogenesis has been widely accepted to treat craniosynostosis, it occasionally results in wound complications. Positing that they are attributable to the tense pericranium under the scalp, we developed a simple technique to relax the pericranial flap.

Methods

In 12- to 15-month-old infants (mean 13 months), we placed a coronal skin incision and dissected the scalp at the subgaleal layer. Then, we peeled the intact pericranium away from the skull along the planned osteotomy to obtain flaps with pedicles on the caudal part. After osteotomy and setting of the distraction device, the pericranial flaps freed from the scalp flap were repositioned to fit the osteotomy line, dura, and distraction device. The galea and skin were approximated layer by layer.

Results

The shape of the skull was successfully corrected, and the bone defect created by expansion was filled by osteogenesis in all patients. During a mean follow-up period of 42.2 months, we encountered no wound complications.

Conclusions

The replaced relaxed pericranium closely adhered to the osteotomy, and the distraction device facilitated vascular growth and bone restoration. Bone resorption was prevented and skin expansion promoted. In patients with iatrogenic dural injury, the pericranium over the injured dura serves as a barrier to prevent cerebrospinal fluid leakage.  相似文献   
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