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181.
A case of plasma cell leukaemia of non-producer type is described. The patient presented with typical clinical features of plasma cell myeloma, including multiple osteolytic lesions, hypercalcaemia, renal failure and reduced polyclonal immunoglobulins, except that M-component was not detected in either the serum or urine. Morphological examinations showed a plasmacytoid appearance of the neoplastic cells, while immunological studies failed to detect cytoplasmic immunoglobulin or secretory capacity. The surface phenotype of CD38+, PCA-1+, DR-, CD20-, CD24-, CD9-, CD10- and surface immunoglobulin- was compatible with mature plasma cells. Chromosomal analysis showed the 14q+ marker due to translocation (6;14) and deletion of the short arm of chromosome 1. Analysis of immunoglobulin genes revealed the presence of heavy chain gene rearrangement, but the light chain genes, both kappa and lambda, remained in germline configuration. Such defective immunoglobulin gene rearrangement may be responsible for the failure of immunoglobulin biosynthesis and secretion by the neoplastic plasma cells. Furthermore, it is suggested that the morphological and phenotypic development of B cells may not necessarily depend on immunoglobulin light chain gene rearrangement, and that the oncogenic event in myeloma may occur at an earlier stage of B cell differentiation.  相似文献   
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Behaviors comparable to human child maltreatment are observed widely among mammals, in which parental care is mandatory for offspring survival. This article first reviews the recent findings on the neurobiological mechanisms for nurturing (infant caregiving) behaviors in mammals. Then the major causes of attack/desertion toward infants (conspecific young) in nonhuman mammals are classified into five categories. Three of the categories are ‘adaptive’ in terms of reproductive fitness: (i) attack/desertion toward non‐offspring; (ii) attack/desertion toward biological offspring with low reproductive value; and (iii) attack/desertion toward biological offspring under unfavorable environments. The other two are nonadaptive failures of nurturing motivation, induced by: (iv) caregivers’ inexperience; or (v) dysfunction in caregivers’ brain mechanisms required for nurturing behavior. The proposed framework covering both adaptive and nonadaptive factors comprehensively classifies the varieties of mammalian infant maltreatment cases and will support the future development of tailored preventive measures for each human case. Also included are remarks that are relevant to interpretation of available animal data to humans: (1) any kind of child abuse/neglect is not justified in modern human societies, even if it is widely observed and regarded as adaptive in nonhuman animals from the viewpoint of evolutionary biology; (2) group‐level characteristics cannot be generalized to individuals; and (3) risk factors are neither deterministic nor irreversible.  相似文献   
184.
Purpose: The Basidiomycete fungus Agaricus blazei Murill has traditionally been used as a health food for the prevention of cancer. Methods: We examined whether beta-(1–6)-D-glucan extracted from A. blazei is a potential anticancer agent in an in vitro and in vivo animal model. Results: Here we show that (1) beta-glucan had cytotoxic effect against human ovarian cancer HRA cells, but not against murine Lewis lung cancer 3LL cells, in vitro; (2) beta-glucan promotes p38 MAPK activity for suppressing HRA cell proliferation and amplifying the apoptosis cascade; (3) beta-glucan stimulates translocation of the proapoptotic protein, Bax, from the cytosol to mitochondria, cytochrome c release, and subsequent caspase-9 activation; (4) treatment with SB203580, a p38 MAPK-specific inhibitor, suppresses beta-glucan-induced effects, indicating that activation of p38 MAPK is involved in the suppression of cell proliferation and mitochondrial activation-mediated cell death pathway; (5) in mice, oral supplementation with beta-glucan reduces pulmonary metastasis of 3LL cells and peritoneal disseminated metastasis of HRA cells and inhibits the growth of these metastatic tumors in lung or peritoneal cavity, in part, by suppressing uPA expression; and (6) in an in vivo experimental metastasis assay, however, the oral supplementation with beta-glucan after i.v. tumor cell inoculation did not reduce the number of lung tumor colonies. Conclusion: Treatment with beta-glucan may be beneficial for cancer patients with or at risk for metastasis. The beta-glucan-dependent signaling pathways are critical for our understanding of anticancer events and development of cancer therapeutic agents.  相似文献   
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Hepatic amyloid light‐chain (AL) amyloidosis is characterized by abnormal deposition of amyloid fibrils in the liver. As this precursor protein is produced by a proliferative plasma cell clone in the bone marrow, liver transplantation (LT) does not affect the disease's progression. Here, we describe the successful treatment using bortezomib‐ and dexamethasone‐based chemotherapy, following LT, of hepatic AL amyloidosis in a 65‐year‐old woman with progressive liver failure. The patient presented with progressive hepatic dysfunction accompanied by hepatorenal syndrome requiring hemodialysis, and living donor LT was successfully performed. Histology revealed amyloid deposits in the liver and stomach, and serum immunofixation revealed AL amyloidosis (κ‐type). The patient began chemotherapy on day 45 after the LT, and remission was achieved after one course. She was subsequently discharged 83 days after the LT, with normal liver and renal function, and no clinical evidence of recurrent disease was observed at the latest follow up (22 months post‐LT).  相似文献   
187.
Hepatitis B virus(HBV) persistently infects approximately 350 million people, and approximately 600000 liverrelated deaths are observed per year worldwide. HBV infection is also one of the major risk factors for hepatocellular carcinoma(HCC). The persistence of serum hepatitis B e antigen(HBe Ag) and high level of serum HBV DNA are thought to reflect a high HBV replication status in hepatocytes, causing cirrhosis, HCC and liver-related deaths. It has been reported that antiviral therapy, such as peginterferon and nucleos(t)ide analogues(NUCs), could suppress liver-related death by inhibiting the HBV DNA levels and inducing seroconversion from HBe Ag to antibody to HBe antigen. Currently, peginterferon is widely used, but there are also several disadvantages in the use of peginterferon, such as various adverse events, the administration route and duration. It is difficult to predict the effects of treatment and interferon is contraindicated for the patients with advanced fibrosis of the liver and cirrhosis. With respect to NUCs, entecavir and tenofovir disoproxil fumarate are current the first-choice drugs. NUCs can be administered orally, and their anti-viral effects are stronger than that of peginterferon. However, because cessation of NUC administration leads to high levels of viral replication and causes severe hepatitis, they must be administered for a long time. On the other hand, the use of both interferon and NUCs cannot eliminate covalently closed circular DNA of HBV. In this review, we evaluate the natural course of chronic HBV infection and then provide an outline of these representative drugs, such as peginterferon, entecavir and tenofovir disoproxil fumarate.  相似文献   
188.
BACKGROUND: Major and minor depressive episodes in cancer patients are frequent and are frequently seen as the first depressive episode in a patient's life. However, the neurological basis of these depressive episodes remains largely unknown. METHODS: Subjects were 51 breast cancer survivors (BCS) who had no history of any depressive episode before the cancer diagnosis (11 BCS with a history of a first minor depressive episode after cancer diagnosis, 11 BCS with a history of a first major depressive episode after cancer diagnosis, and 29 BCS with no history of any depressive episode after cancer diagnosis). We analyzed the prefrontal cortex (PFC) and amygdala volumes in a 1.5-Tesla Magnetic Resonance Imaging scanner. We characterized the structural correlates of depression using two complementary approaches. The first was voxel-based morphometry (VBM) that allowed us to scan the entire brain for reactive gray matter deficit. The second was classical volumetry focusing on the amygdala. RESULTS: Voxel-based morphometry revealed no brain region, including PFC, for which volume was significantly different among the three groups. There were trend-level differences in the left amygdala volume in the manual tracing method among the three groups. The left amygdala volumes in the subjects with a first minor and/or major depressive episode were significantly smaller than in those with no history of any depressive episode. CONCLUSIONS: It might be suggested that amygdala volume was associated with a first minor and/or major depressive episode after cancer diagnosis.  相似文献   
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OBJECTIVE: To demonstrate that individualized optimal fetal growth norms, accounting for physiologic and pathologic determinants of fetal growth, better identify normal and abnormal outcomes of pregnancy than existing methods. METHODS: In a prospective cohort of 38,033 singleton pregnancies, we identified 9,818 women with a completely normal outcome of pregnancy and characterized the physiologic factors affecting birth weight using multivariable regression. We used those physiologic factors to individually predict optimal growth trajectory and its variation, growth potential, for each fetus in the entire cohort. By comparing actual birth weight with growth potential, population, ultrasound, and customized norms, we calculated for each fetus achieved percentiles, by each norm. We then compared proportions of pregnancies classified as normally grown, between 10th and 90th percentile, or aberrantly grown, outside this interval, by growth potential and traditional norms, in 14,229 complicated pregnancies, 1,518 pregnancies with diabetes or hypertensive disorders, and 1,347 pregnancies with neonatal complications. RESULTS: Nineteen physiologic factors, associated with maternal characteristics and early placental function, were identified. Growth potential norms correctly classified significantly more pregnancies than population, ultrasound, or customized norms in complicated pregnancies (26.4% compared with 18.3%, 18.7%, 22.8%, respectively, all P<.05), pregnancies with diabetes or hypertensive disorders (37.3% compared with 23.0%, 28.0%, 34.0%, respectively, all P<.05) and neonatal complications (33.3% compared with 19.7%, 24.9%, 29.8%, respectively, all P<.05). CONCLUSION: Growth potential norms based on the physiologic determinants of birth weight are a better discriminator of aberrations of fetal growth than traditional norms. LEVEL OF EVIDENCE: II.  相似文献   
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