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71.
Hypochondroplasia (HCH) is the mildest phenotype among fibroblast growth factor receptor 3 (FGFR3)-associated skeletal dysplasias. Affected individuals usually presents with mild short stature in preschool age. It was uncommon that a diagnosis of HCH is made in young affected children. Recently, however, prenatal ultrasound (US) has increased likelihood of detecting in utero mild short limbs. There have been a few reports on the early diagnosis of HCH in the neonatal period preceded by a suspicion of skeletal dysplasia on fetal US. However, the proper diagnosis of HCH is hampered by absence of the radiological criteria relevant to age, particularly those in the neonatal period. We report on the clinical and radiological findings in two HCH children with a FGFR3 mutation. In both children, fetal US showed short femora and relatively increased biparietal diameter (BPD). However, postnatal assessment failed to make a specific diagnosis in the neonatal period. The correct diagnosis of HCH was accomplished by reassessment after exacerbation of postnatal short stature. In retrospective radiological review, the radiological findings relevant to HCH were discernible more easily in the neonatal period than at age of 3 years.  相似文献   
72.
AIM: To determine whether absorbable sutures or non-absorbable sutures are better in preventing surgical site infection (SSI), in this paper we discuss the results of a randomized clinical trial which examined the type of sutures used during hepatectomy. METHODS: All hepatic resections performed from January 2007 to November 2008 at the Department of Surgery at Iizuka Hospital in Japan were included in this study. There were 125 patients randomly assigned to an absorbable sutures (Vicryl) group or non-absor...  相似文献   
73.
A 73-year-old man with fever, lumbago and hemosputum showed ground-glass opacity around multiple lung nodules on chest computed tomography. Examination of the man revealed anemia. Specimens obtained by video-assisted thoracic surgery revealed angiosarcoma, but the primary site of angiosarcoma could not be detected before autopsy. Angiosarcoma is a rare malignant neoplasm with rapid proliferation and they can arise at any region of the body. It can originate in the skin, soft tissue, liver or heart. Their multicentric and local recurrence easily leads us to misdiagnosis, and we have struggled to reach diagnosis and its origin. Angiosarcoma should be included in the different diagnosis of diffuse pulmonary hemorrhage with multiple lung nodules.  相似文献   
74.
OBJECTIVES: Gastric intestinal metaplasia (GIM) associated with H. pylori (HP) has been considered a premalignant lesion. However, GIM phenotype associated with HP infection and gastric cancer is unclear. The expression of COX-2 in relation to GIM phenotype is also unknown. METHODS: We evaluated cellular phenotype and COX-2 expression in the GIM from HP-positive and -negative patients from Japan in the absence of gastric cancer (n = 31) by using a colon epithelium specific monoclonal antibody (mAb Das-1) and anti-COX-2 antibody. COX-2 expression was also examined in patients with gastric cancer (n = 34), both in the cancer and in the GIM areas away from the cancer field. RESULTS: Sixty-eight percent of HP-positive GIM reacted with mAb Das-1, whereas the reactivity in the HP-negative GIM was only 25% (P < 0.001). The COX-2 expression was present in 32% of HP-positive GIM and in only 9% of HP-negative GIM (P < 0.001). In the cancer group, COX-2 expression was localized both in the cancer area (94%) and in the GIM (82%) away from the cancer. Each of the COX-2-positive tissue was also positive to mAb Das-1. CONCLUSION: HP infection is highly associated with the development of colonic-phenotype of GIM, and about half of them expressed COX-2. COX-2 expression was frequent in both gastric cancer and the GIM adjacent to the cancer. The results suggest that the presence of mAb Das-1 and COX-2 reactivity in the GIM identify the subgroup of patients who may be at risk for gastric cancer and may need close surveillance.  相似文献   
75.
BACKGROUND: Diacylglycerol (DAG) suppresses the postprandial increase in serum triglycerides, and has antiobesity effects. On the other hand, plant sterol esters (PSE) lower serum cholesterol levels in hypercholesterolemia. Thus, DAG-containing PSE (PSE/DAG) would be expected to maintain an appropriate serum cholesterol level and decrease the risk of arteriosclerotic disorders. Several recent studies, however, report negative effects of PSE on serum fat-soluble (pro)vitamin levels. The objective of this study was to investigate the effect of PSE/DAG on serum retinol, beta-carotene, and alpha-tocopherol levels using a threefold excess of the effective dose obtained in our previous study. METHODS: A randomized placebo-controlled double-blind parallel study was performed in healthy and mildly hypercholesterolemic subjects, in which the subjects ingested 1.2 g PSE/30 g DAG for 2 weeks in the form of mayonnaise-type products. Triacylglycerol (TAG) mayonnaise was used as a control. RESULT: There were no subjective adverse effects or changes in serum retinol, alpha-tocopherol, and beta-carotene levels, abdominal symptoms, hematologic values, or blood biochemical values. CONCLUSION: Ingestion of a threefold excess of PSE/DAG for 2 weeks had no adverse effects compared to ingestion of conventional TAG mayonnaise.  相似文献   
76.
BACKGROUND: Staphylococcus aureus-producing superantigens (SAgs), such as staphylococcal enterotoxin B (SEB) or toxic shock syndrome toxin-1 (TSST-1), are frequently observed in atopic dermatitis (AD). However, little has been done to establish the association of immune responses to SAgs and the therapeutic response to immunosuppressive drugs in AD. Therefore, we investigated the prevalence and role of SAgs in the pathophysiology and immunosuppressive drug sensitivity in AD patients. METHODS: We classified 29 patients into two groups on the basis of their clinical AD scores: a low-score group (n = 14) corresponding to mild to moderate patients and a high-score group (n = 15) corresponding to severe patients. We estimated the plasma anti-SEB or TSST-1 IgE of these patients and healthy subjects by ELISA. We also estimated individual drug sensitivity by determining drug concentrations that would give 50% inhibition (IC(50)) of peripheral-blood mononuclear cell (PBMC) proliferation in vitro. RESULTS: The levels of plasma anti-SEB or TSST-1 IgE in the severe patients were significantly higher than those in the mild to moderate patients (p < 0.05 and p < 0.01, respectively). When stimulated with concanavalin A in vitro, PBMCs in the severe patients exhibited low sensitivity to the suppressive efficacy of tacrolimus (FK506) as compared to the mild to moderate patients (p < 0.01). Furthermore, there was a significant correlation between the IC(50)s of FK506 and plasma anti-TSST-1 IgE levels (p < 0.01). CONCLUSIONS: We showed that PBMCs in severe AD patients exhibited lower sensitivity to FK506, and had higher plasma levels of anti-TSST-1 IgE as compared to the mild AD patients. SAgs appear to be one of the causes of decreased PBMC sensitivity to FK506, and therefore an alternative treatment would be useful based on the individual drug sensitivity data and anti-TSST-1 IgE levels.  相似文献   
77.
BACKGROUND: It is important to confirm preoperative tracheobronchial invasion to enable the selection of the most appropriate treatment. OBJECTIVE: This study was performed to compare the usefulness of computed tomography (CT), magnetic resonance image (MRI) and bronchoscopy by endobronchial ultrasonography (EBUS) for the assessment of invasion of thyroid or esophageal cancer in cases with suspected tracheobronchial invasion. METHODS: In cases with suspected contact between the tumor and tracheobronchial wall, CT, MRI and EBUS indicated deformity of the tracheobronchial wall due to the adjacent mass. The final diagnosis was based on surgical and histological results, and/or clinical follow-up. RESULTS: Fifty-four patients were included in this study. Based on the findings of CT, MRI and EBUS, invasion was suspected in 29, 28 and 25 patients, respectively. Seventeen patients did not undergo surgery based on the results of CT, MRI and bronchoscopy with EBUS. Final diagnosis was intact trachea or bronchial adventitia in 26 patients and invasion in 28 patients. The sensitivity and specificity of CT, MRI and EBUS for invasion were 59 and 56, 75 and 73, and 92 and 83%, respectively. The accuracy of EBUS was significantly greater than that of CT in the present study (p = 0.0011). The accuracy of EBUS was significantly different from that of CT and MRI in the surgically treated patients (p = 0.005 and p = 0.032, respectively). CONCLUSION: EBUS is the most useful technique for determining the depth and extent of tumor invasion into the airway wall. The combination of MRI and EBUS will contribute to surgical planning in patients with esophageal and thyroid cancer.  相似文献   
78.
Structural differences between dynein and kinesin suggest a unique molecular mechanism of dynein motility. Measuring the mechanical properties of a single molecule of dynein is crucial for revealing the mechanisms underlying its movement. We measured the step size and force produced by single molecules of active cytoplasmic dynein by using an optical trap and fluorescence imaging with a high temporal resolution. The velocity of dynein movement, 800 nm/s, is consistent with that reported in cells. The maximum force of 7-8 pN was independent of the ATP concentration and similar to that of kinesin. Dynein exhibited forward and occasional backwards steps of approximately 8 nm, independent of load. It is suggested that the large dynein heads take 16-nm steps by using an overlapping hand-over-hand mechanism.  相似文献   
79.

Background and aims

In two Japanese infants with neonatal cholestasis, 3-oxo-Δ4-steroid 5β-reductase deficiency was diagnosed based on mutations of the SRD5B1 gene. Unusual bile acids such as elevated 3-oxo-Δ4 bile acids were detected in their serum and urine by gas chromatography–mass spectrometry. We studied effects of oral chenodeoxycholic acid treatment.

Patients and methods

SRD5B1 gene analysis used peripheral lymphocyte genomic DNA. Diagnosis and treatment of these two patients were investigated retrospectively and prospectively investigated.

Results

With respect to SRD5B1, one patient was heterozygous (R266Q, a novel mutation) while the other was a compound heterozygote (G223E/R261C). Chenodeoxycholic acid treatment was effective in improving liver function and decreasing unusual bile acids such as 7α-hydroxy- and 7α,12α-dihydroxy-3-oxo-4-cholen-24-oic acids in serum and urine.

Conclusion

Primary bile acid treatment using chenodeoxycholic acid was effective for these patients treated in early infancy before the late stage of chronic cholestatic liver dysfunction.  相似文献   
80.
Silver-Russell syndrome (SRS) is characterized by growth failure and dysmorphic features and is frequently caused by hypomethylation (epimutation) of the H19-DMR. Although molecular and clinical studies have extensively been performed for SRS patients themselves, such studies have not been carried out for placentas. We identified 20 epimutation-positive and 40 epimutation-negative Japanese SRS patients and obtained placental weight data from 12 epimutation-positive and ten epimutation-negative patients and paraffin-embedded placental tissues for molecular and histological examinations from three epimutation-positive and two epimutation-negative patients. Methylation patterns were comparable between leukocytes and placentas in both epimutation-positive and epimutation-negative patients. Epimutations resulted in virtually no IGF2 expression and biallelic slight H19 expression in the leukocytes and obviously reduced IGF2 expression of paternal origin and nearly normal H19 expression of maternal origin in the placentas. Epimutation-positive patients had characteristic body phenotype and small placentas with hypoplastic chorionic villi, and epimutation-negative patients had somewhat small placentas with hypoplastic chorionic villi or massive infarction. Furthermore, significant correlations were identified between the H19-DMR methylation index and the body and placental sizes and between the placental weight and the body size in the epimutation-positive patients, whereas such correlations were not detected for the head circumference. These results suggest (1) characteristic phenotype and reduced IGF2 expression in the epimutation-positive placentas; (2) similarities and differences in the epigenetic control of the IGF2–H19 domain between leukocytes and placentas; (3) a positive role of the IGF2 expression level, as reflected by the methylation index, in the determination of body and placental growth in epimutation-positive patients, except for the brain where IGF2 is expressed biallelically; (4) involvement of placental dysfunction in prenatal growth failure; and (5) relevance of both (epi)genetic factor(s) and environmental factor(s) to SRS in epimutation-negative patients. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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