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41.
42.
Polycythemia vera (PV) is known to occasionally transform into acute leukemia. Administration of alkylating agents seems to be associated with an increased risk of leukemic transformation of PV. Hypercalcemia is a serious complication of malignancies, but it is uncommon in acute leukemia. In the majority of malignancies with hypercalcemia, elevated parathyroid hormone-related protein (PTHrP) is thought to be the main cause of hypercalcemia. We report a rare case of megakaryoblastic transformation of PV with hypercalcemia. A 62-year-old man was diagnosed as having PV in 1983, and he had received ranimustine and busulfan. He developed acute megakaryoblastic leukemia 17 years after the initial diagnosis of PV. Serum calcium was elevated, the serum level of intact parathyroid hormone (PTH) was suppressed, and the level of intact PTHrP was slightly elevated. He had no lytic bone lesions; however, uncoupling of bone turnover due to an increase in bone resorption and a decrease in bone formation was detected by using biochemical markers. Since the level of PTHrP was slightly elevated from the normal value, we speculated that PTHrP produced in the local field by leukemic cells might have been more abundant than circulating PTHrP. Pamidronate and adrenocortical hormone were effective in reducing the serum calcium level. However, the patient died shortly after the start of induction chemotherapy. The prognosis of cases of PV that has transformed into acute leukemia is generally poor because the majority of such cases are refractory to chemotherapy.  相似文献   
43.
In order to investigate the possible involvement of airway mast cells in bronchial hyperresponsiveness (BHR), we examined whether a patient with systemic mastocytosis would demonstrate BHR against ultrasonically nebulized distilled water (UNDW) and histamine inhalation challenge. A 56-year-old man with systemic mastocytosis underwent both UNDW and histamine inhalation challenge. We also evaluated the effect of beclomethasone dipropionate inhalation (BDI) treatment on the histamine inhalation challenge. The results showed that UNDW inhalation caused no changes in forced expiratory volume in 1 s (FEV1) for this patient. The provocative dose causing a 20% fall (PC20) in FEV1 in the histamine inhalation challenge was 625 microg/mL. After BDI treatment for 8 weeks, the histamine PC20 was still 625 microg/mL. These data suggest that UNDW-induced bronchoconstriction may be independent of airway mast cells and that the mechanism of histamine-induced bronchoconstriction in systemic mastocytosis may be independent of airway inflammation, which is often present in asthmatics.  相似文献   
44.
OBJECTIVE: We assessed the association between infection with CagA-positive and -negative Helicobacter pylori and the risk of gastric cancer in young adults. METHODS: CagA IgG antibodies were measured in sera of subjects participating in a case-control study in Japan. The study subjects were 103 gastric cancer patients <40 yr of age, 100 inpatients with benign diseases, and 101 screenees younger than age 43 yr. RESULTS: Compared with the H. pylori-negative/CagA-negative (H. pylori-/CagA-) group, both the H. pylori-positive/CagA-negative (H. pylori+/CagA-) group and the H. pylori-positive/CagA-positive (H. pylori+/CagA+) groups showed elevated odds ratios for intestinal-type, diffuse-type, early, advanced, proximal, and distal gastric cancers. All the relationships were significant except for the H. pylori+/CagA- group in relation to proximal cancer. The overall odds ratios (95% confidence intervals) for gastric cancer in the H. pylori+/CagA- and the H. pylori+/CagA+ groups were 15.0 (6.4, 35.2) and 14.6 (6.7, 31.9), respectively. Between these two groups, no significant difference was observed in risks for intestinal-type, diffuse-type, early, advanced, proximal, or distal gastric cancer. CONCLUSIONS: In those <40 yr of age, it is concluded that both CagA-positive and CagA-negative H. pylori infections are related to risks of intestinal-type, diffuse-type, early, advanced, and distal gastric cancers.  相似文献   
45.
The treatment of patients with aggressive subclasses of myelodysplastic syndrome (MDS) remains a challenge. In an effort to improve the survival of patients with refractory anemia with excess blasts (RAEB), RAEB in transformation (RAEB-t), or acute myelogenous leukemia transformed from MDS (MDS-AML), we conducted a small trial in which 28 such patients were treated with low-dose cytosine arabinoside (LDAraC) followed by administration of macrophage colony-stimulating factor (M-CSF). The overall rate of response to the treatment was 61%, including 39% with a complete response, which is higher than rates obtained in previous studies in which LDAraC alone was administered to patients with MDS. Median survival was 23.5 months in cases of RAEB, 16.7 months in cases of RAEB-t, and 19.7 months in cases of MDS-AML. The overall survival of the study group appeared to be prolonged in comparison with a historical control group of patients treated with LDAraC alone. It is suggested that M-CSF added to the administration of LDAraC plays an active role in the therapy. No therapy-related death occurred. Some unique actions of M-CSF were suggested in this trial. It is concluded that therapy with LDAraC + M-CSF is a useful treatment option for patients with aggressive subclasses of MDS and MDS-AML to provide better response and survival.  相似文献   
46.
A case of tuberculous pericarditis successfully managed with medical treatment alone was reported. A 78-year-old male was admitted because of cough, dyspnea and fever. Chest X-P and echocardiogram revealed massive pericardial effusion. His clinical symptoms and signs suggested cardiac tamponade. Mycobacterium tuberculosis was detected from pericardial fluid. ADA activity in pericardial fluid was high. Thoracic CT scan showed tracheobronchial, pretracheal, paratracheal and superior mediastinal lymph-node swelling. The diagnosis of tuberculous pericarditis was confirmed. Anti-tuberculous therapy consisting of INH, RFP, EB in combination with prednisolone was started. One month later pericardial effusion was controlled and six months later he was in good clinical condition without surgical treatment.  相似文献   
47.
48.
A heterogeneous spectrum of clinical manifestations caused by mutations in ATP1A3 have been previously described. Here we report two cases of infantile‐onset cerebellar ataxia, due to two different ATP1A3 variants. Both patients showed slowly progressive cerebellar ataxia without paroxysmal or episodic symptoms. Brain magnetic resonance imaging revealed mild cerebellar cortical atrophy in both patients. Whole exome sequencing revealed a de novo heterozygous variant in ATP1A3 in both patients. One patient had the c.460A>G (p.Met154Val) variant, while the other carried the c.1050C>A (p.Asp350Lys) variant. This phenotype was characterized by a slowly progressive cerebellar ataxia since the infantile period, which has not been previously described in association with ATP1A3 variants or in ATP1A3‐related clinical conditions. Our report contributes to extend the phenotypic spectrum of ATP1A3 mutations, showing paediatric slowly progressive cerebellar ataxia with mild cerebellar atrophy alone as an additional clinical presentation of ATP1A3‐related neurological disorders.  相似文献   
49.
50.
Monoclonal antibodies (mAbs) are widely utilized as therapeutic drugs for various diseases, such as cancer, autoimmune diseases, and infectious diseases. Using the avian-derived B cell line DT40, we previously developed an antibody display technology, namely, the ADLib system, which rapidly generates antigen-specific mAbs. Here, we report the development of a human version of the ADLib system and showcase the streamlined generation and optimization of functional human mAbs. Tailored libraries were first constructed by replacing endogenous immunoglobulin genes with designed human counterparts. From these libraries, clones producing full-length human IgGs against distinct antigens can be isolated, as exemplified by the selection of antagonistic mAbs. Taking advantage of avian biology, effective affinity maturation was achieved in a straightforward manner by seamless diversification of the parental clones into secondary libraries followed by single-cell sorting, quickly affording mAbs with improved affinities and functionalities. Collectively, we demonstrate that the human ADLib system could serve as an integrative platform with unique diversity for rapid de novo generation and optimization of therapeutic or diagnostic antibody leads. Furthermore, our results suggest that libraries can be constructed by introducing exogenous genes into DT40 cells, indicating that the ADLib system has the potential to be applied for the rapid and effective directed evolution and optimization of proteins in various fields beyond biomedicine.  相似文献   
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