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51.
In order to investigate the pathogenesis of mutilans-type rheumatoid arthritis (RA), we measured cytokine levels in the bone marrow serum of patients with RA. We studied 35 patients with non-mutilans RA, 19 with mutilans RA, and 20 patients with osteoarthritis (OA) undergoing joint surgery. At the time of surgery, iliac bone marrow and peripheral blood were sampled from all 74 patients and cytokine levels measured. The serum levels of five cytokines (IL-1β, IL-2, IL-3, IL-6 and GM-CSF) were measured by ELISA. Haematologic and inflammatory factors were also measured. Levels of IL-2, IL-6 and GM-CSF in bone marrow serum were significantly higher in all RA patients than in those with OA. Mean (tSD) IL-2 levels were significantly higher in patients with mutilans-type RA (309.8t686.3 pg/ml) than in patients with other types of RA (66.5t173.1 pg/ml; P<0.01). IL-2 was detected significantly more often in patients with mutilans-type RA than in patients with other types of RA (P<0.01). Inflammatory factors were higher in all RA groups than in OA patients. However, the haematologic and immunologic variables were no different between mutilans RA and other types of RA. No correlations were observed between IL-1β, IL-2, IL-3, IL-6 and GM-CSF levels and these laboratory variables. In patients with mutilans-type RA, IL-2 levels in the bone marrow serum were significantly higher than in patients with other types of RA or with OA. This elevation does not appear to be related to systemic inflammation, as there was no correlation with other inflammatory factors. Received: 9 October 2000 / Accepted: 16 July 2001  相似文献   
52.
Lilly Laboratories cell porcine kidney 1 (LLC-PK1) cells transfected with human P-glycoprotein (LLC-PK1-P-gp) are widely used in transport assays to identify drug candidates that function as substrates of this efflux transporter. Endogenous transporters expressed in LLC-PK1 cells may complicate the interpretation of findings from P-gp-mediated transport assays. We investigated the impact of porcine breast cancer resistance protein (Bcrp) in P-gp-mediated transport assays in LLC-PK1 cells. Porcine Bcrp mRNA was detected in both LLC-PK1 wildtype (WT) and LLC-PK1-P-gp cells by quantitative RT-PCR. To investigate the activity and impact of porcine Bcrp, we conducted transport assays using 6 typical BCRP substrates in LLC-PK1 cells. Efflux ratios (ER) of the 6 BCRP substrates in LLC-PK1 WT cells were >2, and were reduced in the presence of the BCRP inhibitor Ko143. The efflux activities of the 6 BCRP substrates were confirmed using MDCKII cells transfected with human BCRP. Net ERs of prazosin and fluvastatin, dual substrates of P-gp and BCRP, determined by dividing ERs in LLC-PK1-P-gp cells by those in LLC-PK1 WT cells, were <2, but increased to >2 in the presence of Ko143. These results indicated that endogenous Bcrp in LLC-PK1 cells was involved in the transport of BCRP substrates and may interfere with the identification of P-gp substrates.  相似文献   
53.

Background

Knowledge of MRI findings in pediatric cerebral infarction is limited.

Objective

To determine whether cortical necrosis and network injury appear in the acute phase in post-stroke children and to identify anatomical location of acute network injury and the ages at which these phenomena are seen.

Materials and methods

Images from 12 children (age range: 0–9 years; neonates [<1 month], n=5; infants [1 month–12 months], n=3; others [≥1 year], n=4) with acute middle cerebral artery (MCA) cortical infarction were retrospectively analyzed. Cortical necrosis was defined as hyperintense cortical lesions on T1-weighted imaging that lacked evidence of hemorrhage. Acute network injury was defined as hyperintense lesions on diffusion-weighted imaging that were not in the MCA territory and had fiber connections with the affected cerebral cortex. MRI was performed within the first week after disease onset.

Results

Cortical necrosis was only found in three neonates. Acute network injury was seen in the corticospinal tract (CST), thalamus and corpus callosum. Acute network injury along the CST was found in five neonates and one 7-month-old infant. Acute network injury was evident in the thalamus of four neonates and two infants (ages 4 and 7 months) and in the corpus callosum of five neonates and two infants (ages 4 and 7 months). The entire thalamus was involved in three children when infarction of MCA was complete.

Conclusion

In acute MCA cortical infarction, MRI findings indicating cortical necrosis or acute network injury was frequently found in neonates and early infants. Response to injury in a developing brain may be faster than that in a mature one.  相似文献   
54.
Rationale:McCune–Albright syndrome (MAS) is a rare disorder characterized by clinical findings, which includes fibrous dysplasia (FD). FD is a benign tumor that leads to increased rates of bone fracture. In some MAS cases with FD, facial deformities, severe pain, and orbital neuropathies are complicated. Aneurysmal bone cyst (ABC) is a benign bone tumor and rare complication of FD.Patient concerns:A 9-year-old boy was admitted to our hospital because of acute visual disturbance.Diagnosis and interventions:The patient was clinically diagnosed as ABC complicated with MAS, and he underwent surgery.Outcomes:After the surgery, his sight became normal. Recurrence of ABC and visual disturbance was not observed in 3 years. Genetic analysis of a tissue sample from the ABC lesion by next-generation sequencing revealed a somatic activating GNAS mutation.Lessons:To the best of our knowledge, this is the first case report of MAS causing optic neuropathy complicated with ABC. ABC complicated with MAS is extremely rare, but it should be considered as a possible diagnosis in patients with acute visual loss and facial swelling. In addition, our case had OAS, which is an uncommon syndrome and a rare complication in ABC with MAS, and rapid decompression of the ABC was effective in improving the patient''s eyesight.  相似文献   
55.
This study aimed at evaluating the usefulness of topoisomerase II alpha (TOP2A) for predicting the effect of anthracycline-based neoadjuvant chemotherapy in breast cancer. The TOP2A status was examined using fluorescent in situ hybridization (FISH) in 14 pre-chemotherapeutic breast cancer tissues, and was also assessed by immunohistochemistry (IHC) in 14 pairs of pre- and post-chemotherapeutic breast cancer specimens. TOP2A gene aberration by IHC tended to show a correlation with pathological responses but this was not statistically significant (p=0.060). On the other hand, the low TOP2A/CEP17 ratio correlated with good pathological responses (p=0.012). TOP2A overexpression was not significantly associated with response (p=0.580). Our results thus suggest that the TOP2A/CEP17 ratio may be a useful predictor of the effects of anthracycline-based neoadjuvant chemotherapy in breast cancer.  相似文献   
56.
Porcine endocrine cells were isolated from pancreas of 6-month-old pigs by two-step enzymatic digestion procedures. They were separated by the density gradient (isopycnic) centrifugation method using Histopaque-1077. Isolated cells were cultured and divided into two groups: suspension cells and adhesion cells. Suspension cells maintained their cell numbers on and after 7 days in culture. Approximately 1 x 10(7) cells were obtained from single pancreas of a 6-month-old pig. The cultured suspension cells took up dithizone (DTZ) staining 14 days after isolation in culture and indicated the presence of beta-cells. In in vitro study, the suspension cells were capable of secreting insulin into the culture medium. The suspension cells were tested for insulin and glucagon staining by Western blot analysis. These results indicated the maintenance of endocrine cell function after isolation. However, cultured adhesion cells failed to maintain their function during culture. In in vivo study, the suspension cells were transplanted into diabetes-induced nude mice. Reduction in blood glucose level was obtained after transplantation. Intraperitoneal glucose tolerance test (IPGTT) results showed a normal pattern of blood glucose clearance. After 1 week, the transplanted endocrine cells were detected with anti-insulin antibody by immunostaining and it showed the presence of viable beta-cells under the renal capsule of nude mice. Collectively, our results suggest that isolated and cultured suspension porcine endocrine cells maintained their endocrine function. These endocrine cells can be used as isolated islets for further study, including transplantation experiments.  相似文献   
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