Clinicopathologic features and incidence of invasive lobular carcinoma in Japanese women

Intending to clarify the true Incidence of Invasive lobular carcinoma of the breast In Japanese women as well as the frequency of unilateral multlcentriclty, 362 cases of clinically defined monocentrlc breast cancer without pre-operative biopsy (previously fine needle aspiration or needle biopsy were routinely carried out for every case) were examined by whole mammary gland serial sectioning. On the basis of pathology and the World Health Organization classification of breast tumors, each case was assigned to one of two main histologlc types: Invasive lobular carcinoma (ILC) or Invasive ductal carcinoma (IDC). Invasive lobular carcinoma was further separated into classic and variant types by employing previously published criteria. Twenty-one cases of ILC (5.8%) were diagnosed, which Is more than In most previous Japanese studies. Unilateral multicentric breast carcinoma was detected In 9.5% of ILC and 16.1% of IDC (the difference was found not significant). Microscopically, ILC tumors were found to be, on average, larger than IDC. Patients with classic type ILC tended to be younger than those with variant type or IDC. Estrogen receptor expression was found more frequently In variant type ILC than in classic type. These results suggest that the incidence of invasive lobular carcinoma of the breast In Japanese women is low and that unilateral multicentricity Is not significantly higher in ILC than in IDC.     

Mutation analysis of HNF-4 binding sites in the human glucose-6-phosphatase promoter

HNF-4, a member of the nuclear receptor superfamily, binds to HNF-4 response elements (HRE), consisting of a direct repeat of the hexameric half-sites spaced by 1 nt (direct repeat 1) and activates a number of genes, which play central roles in fatty acids and glucose metabolism. Glucose-6-phosphatase (G6Pase) catalyzes the terminal step in the gluconeogenic and glycogenolytic pathways. A previous study has shown that HNF-4 binds to two DR1s in the regions A (located between -266 and -234) and B (located between -306 and -274) on the human G6Pase promoter. We found that the region B contains the one more DR1 element, composed of the two half-sites, designated half-sites a and b, the latter of which overlaps with the previously identified DR1 consisting of two half-sites, designated half-sites b and c. In this study, electrophoretic mobility shift assay (EMSA) using point mutations in each half-site a, b, or c indicated that HNF-4 binds to the combination of half-sites a and b, but not to half-sites b and c. Furthermore, mutational analysis demonstrated that, in the context of the human G6Pase promoter, the half-sites a and b, but not the half-sites b and c, are required for the stimulatory effect of HNF-4. These results suggested that the DR1 element containing the half-sites a and b is a functional HRE that mediates the induction of hG6Pase promoter activity by HNF-4.     

The course ofAngiostrongylus cantonensis infection in athymic nude and neonatally thymectomized mice

BALB/c athymic nude and thymus-reconstituted nude mice and neonatally thymectomized BALB/c mice were infected with stage 3 larvae ofAngiostrongylus cantonensis and the worm burdens of the mice were determined at various times after infection. When the nude and thymectomized mice were exposed to the parasite, some worms were found to migrate from the brain to lungs but died there without reaching maturity. This pulmonary arterial migration of the worms in the nude mice did not occur following thymic reconstitution. These data suggest that the inability of murine intracranial worms to migrate to the lungs is at least in part due to thymus-dependent mechanisms, and also that the failure of worm maturation in mouse lungs might be due to thymus-independent immune mechanisms and/or nonimmunological mechanisms.     

Human thymus-lymphoid tissue antigen and its presence in leukaemia and lymphoma

An antiserum was prepared by immunizing rabbits with human leukaemic tissue homogenate. Prior to immunization, the rabbits had been made tolerant to normal peripheral leucocytes by repeated injections during the neonatal period to suppress the appearance of antibodies against normal tissue components. When the antiserum was tested by gel diffusion precipitation test, it gave one precipitin line against malignant tissue extracts from most leukaemia and lymphoma cases tested, and against normal thymuses and some spleens and lymph nodes as well. It did not react with tissue extracts prepared from normal non-lymphoid tissus. The antigen responsible for the reaction appeared in foetal thymus at 3 months of gestation and persisted throughout life. It appeared in embryonic spleen after 6 months of gestation and in lymph nodes even later, although in spleen and lymph nodes it was not as invariably demonstrated as in the thymus. Neoplasms of other than lymphoid origin were predominantly negative for the antigen; occasional exceptions were probably due to large amounts of infiltrating lymphoid tissue. Antigen localization was studied by the fluorescent antibody method. The cytoplasm of almost all thymocytes, about 30% spleen cells and 20–40% peripheral lymphocytes was stained. Bone marrow, brain, thyroid, liver and kidney cells were negative. The antigen was partially purified from the soluble fraction of thymus homogenate by ion exchange column chromatography and preparative electrophoresis. Its possible use as a marker for thymus derived normal and neoplastic cells has been discussed.     

Potential tumor suppressive pathway involving DUSP6/MKP-3 in pancreatic cancer

We previously found frequent loss of heterozygosity at 12q21 and 12q22-q23.1 in primary pancreatic cancers, and the DUSP6/MKP-3 gene residing in this region at 12q22 lost its expression in the great majority of pancreatic cancer cell lines. The DUSP6/MKP-3 protein is a dual-specificity phosphatase that dephosphorylates the active form of ERK, making a feedback loop to control ERK activity. Gain-of-function mutations of KRAS2 occur in the great majority of pancreatic cancer cells, and loss of expression of DUSP6/MKP-3 may synergistically promote constitutive activation of ERK and uncontrolled cell growth. To study loss of the feedback pathway and its impact on pancreatic cancer cell growth, we first investigated the expression of DUSP6/MKP-3 in primary pancreatic cancer tissues immunohistochemically; we found up-regulation in mildly as well as severely dysplastic/in situ carcinoma cells and down-regulation in invasive carcinoma, especially in the poorly differentiated type. Adenovirus-mediated reintroduction of DUSP6/MKP-3 into cultured pancreatic cancer cells induced strong expression of recombinant DUSP6/MKP-3 and reduction of phosphorylated ERK in a dose-dependent manner based on the multiplicity of infection and resulted in suppression of cell growth. Moreover, analyses by flow cytometry and immunocytochemistry revealed that the exogenous expression of DUSP6/MKP-3 induced apoptosis. These results show that DUSP6 exerts apparent tumor-suppressive effects in vitro and suggest that DUSP6 is a strong candidate tumor suppressor gene at 12q22 locus.     

Effect of increased task procedures on correlation dimensions of the electroencephalogram

Changes in correlation dimensions of the electroencephalogram (EEG) were examined in three different tasks. These three tasks differed from each other with respect to the number of procedures. In the present experiment, left-hand movement and mental arithmetic were controlled, respectively, during an auditory linguistic task. Subjects were 13 healthy right-handed males. EEG signals from eight electrode sites were analyzed and the correlation dimensions were obtained. In addition, the relative power was obtained for the alpha band. An increase in the number of procedures yielded high dimensionality on the occipital EEG. In contrast, left-hand movement had no significant effect on EEG dimensions over the motor area. The relative power of the alpha band was seen to decrease in all channels as the number of procedures increased. The fact that changes in EEG dimensions did not necessarily exhibit a simple correspondence to changes in alpha wave activity was also discussed.     

Prevalence and characterization of leukotoxin-producing Staphylococcus intermedius in Isolates from dogs and pigeons

Staphylococcus intermedius isolates from dogs (n = 44) and pigeons (n = 62) were categorized into 12 types by intergenic ribosomal DNA spacer polymorphism analysis. All isolates from pigeons were lukS positive and all isolates from dogs were lukS and lukF positive by dot blot analysis. The mean leukotoxicity titer for dog isolates was at least 129-fold higher than that for pigeon isolates.     

Developmental changes in concentrations and distributions of neurotrophins in the monkey cerebellar cortex

Neurotrophins are involved in the survival, differentiation, migration and neurite outgrowth of various neuronal populations. Neurotrophins and their receptors are widely expressed in the developing cerebellum of various experimental animals. To gain some insight into the possible roles played by these molecules in monkey cerebellum, we examined the protein levels of BDNF, NT-4/5 and NT-3 and distributions of those neurotrophins and TrkC, a high affinity receptor for NT-3, in the cerebellum of developing macaque monkeys using ELISAs and immunohistochemical methods. We found that the level of BDNF increased during development, while the level of NT-3 was higher during embryonic stages and decreased toward adulthood. The level of NT-4/5 increased from embryonic stages to infant stages and gradually declined with age. Among the three neurotrophins, BDNF immunoreactivity was found in all kinds of cerebellar neurons, including all inhibitory interneurons, throughout the postnatal periods examined, indicating that BDNF may be an essential factor for the maintenance of cerebellar neural functions. The Bergmann glial fibers and the internal part of the external granule cell layer were strongly NT-3 immunopositive at the early postnatal stages, and more weakly immunoreactive toward adulthood. In addition, we found that the premigratory precursors of the granule cells were TrkC immunopositive at early postnatal stages. These findings suggest that NT-3 in Bergmann glial fibers may be involved in the migration of the premigratory granule cells.     

Severe Neutropenia in Japanese Patients with X-Linked Agammaglobulinemia

X-linked agammaglobulinemia (XLA) is clinically characterized by recurrent bacterial infections during early infancy. Although it is not a phagocytic disorder, XLA is sometimes associated with neutropenia. We conducted a nation-wide survey to determine the frequency of neutropenia among Japanese XLA patients. Responses were received from 87 (86%) of 101 patients in which BTK mutations were previously identified, and of these, 16 (18%) had neutropenia. All episodes of neutropenia occurred before initiation of intravenous immunoglobulin (IVIG) replacement therapy. Two XLA patients died of multiple organ failure caused by severe neutropenia and Pseudomonas sepsis before initiation of IVIG replacement therapy. These results suggest that, in some cases, severe bacterial infections in XLA patients might be caused not only by antibody deficiencies but also by neutropenia.     

Clinical heterogeneity of neonatal intrahepatic cholestasis caused by citrin deficiency: case reports from 16 patients

A deficiency of citrin, which is encoded by the SLC25A13 gene, causes both adult-onset type II citrullinemia (CTLN2) and neonatal intrahepatic cholestasis (NICCD). We analyzed 16 patients with NICCD to clarify the clinical features of the disease. Severe intrahepatic cholestasis with fatty liver was the most common symptom, but the accompanying clinical features were variable, namely; suspected cases of neonatal hepatitis or biliary atresia, positive results from newborn screening, tyrosinemia, failure to thrive, hemolytic anemia, bleeding tendencies and ketotic hypoglycemia. Laboratory data showed elevated serum bile acid levels, hypoproteinemia, low levels of vitamin K-dependent coagulation factors, and hypergalactosemia. Hypercitrullinemia was detected in 11 out of 15 patients examined. Most of the patients were given a lactose-free and/or medium chain triglycerides-enriched formula and lipid-soluble vitamins. The prognosis of the 16 patients is going fairy well at present, but we should observe these patients carefully to see if they manifest any symptom of CTLN2 in the future.