Adenosquamous carcinoma of the pancreas

A 58-year-old Japanese man was admitted complaining of abdominal pain. An abdominal computed tomography examination demonstrated a tumor in the head of the pancreas and multiple calcifications. A laparotomy was performed and the tumor was removed by Whipple's operation. Histologically, the neoplasm that invaded the duodenal wall and the papilla of Vater was composed of nests of malignant squamous cells with intercellular bridges and showed the formation of keratinized pearls with a small area of concurrently neoplastic glandular and squamous elements. On the basis of these features, the diagnosis of adenosquamous carcinoma of the pancreas was made. The patient died 18 months after the operation. The neoplastic behavior of this rare primary pancreatic carcinoma is similar to that of duct cell carcinoma as well as pure squamous cell carcinoma of the pancreas. As the pancreas can be the target of metastases of squamous carcinomas from other organs it is wise to be aware of this rare entity.

Cyclin I: a new cyclin encoded by a gene isolated from human brain

A new member of the cyclin family has been isolated from an equalized cDNA library derived from human forebrain cortex. This putative cyclin, designated cyclin I, contains a typical cyclin box near the N-terminus and a PEST sequence near the C-terminus. Cyclin I shows the highest sequence similarity in the cyclin box to cyclins G and E, while the similarity between cyclins I and G also extends toward the C-terminus from the cyclin box. Cyclin I mRNA was expressed at high levels in postmitotic tissues, including skeletal muscle, heart, and brain, and was expressed constantly during cell cycle progression. The expression of cyclin I mRNA does not correlate directly to the cell cycle, and therefore cyclin I may be a novel cyclin member that functions independently of the cell cycle control.

Protocadherin Pcdh2 shows properties similar to, but distinct from, those of classical cadherins

Cell adhesion and several other properties of a recently identified cadherin-related protein, protocadherin Pcdh2, were characterized. A chimeric Pcdh2 in which the original cytoplasmic domain was replaced with the cytoplasmic domain of E-cadherin was expressed in mouse L cells. The expressed protein had a molecular mass of about 150 kDa and was localized predominantly at the cell periphery, as was the wild-type Pcdh2. In a conventional cell aggregation assay, the transfectants showed cell aggregation activity comparable to that of classical cadherins. This activity was Ca(2+)-dependent and was inhibited by the addition of anti-Pcdh2 antibody, indicating that the chimeric Pcdh2, and probably the wild-type Pcdh2, has Ca(2+)-dependent cell aggregation activity. Mixed cell aggregation assay using L cells and different types of transfectants showed that the activity of Pcdh2 was homophilic and molecular type specific and that Pcdh2 was transfectants did not aggregate with other types of transfectants or with L cells. In immunoprecipitation, the chimeric Pcdh2 co-precipitated with a 105 kDa and a 95 kDa protein, whereas wild-type Pcdh2 co-precipitated with no major protein. Pcdh2 was easily solubilized with non-ionic detergent, in contrast to the case of classical cadherins. On immunofluorescence microscopy, the somas of Purkinje cells were diffusely stained with anti-human Pcdh2 antibody. Mouse Pcdh1 and Pcdh2 were mapped to a small segment of chromosome 18, suggesting that various protocadherins form a gene cluster at this region. The present results suggest that Pcdh2, and possibly other protocadherins as well as protocadherin-related proteins such as Drosophila fat, mediate Ca(2+)-dependent and specific homophilic cell-cell interaction in vivo and play an important role in cell adhesion, cell recognition, and/or some other basic cell processes.

Endothelin-1 and big endothelin-1 increase in human endometrium during menstruation

OBJECTIVES

Although the physiologic and pathologic roles of endothelin-1 in reproduction have been investigated, little is known about human uterine tissue levels. We studied the levels of immunoreactive endothelin-1 and immunoreactive big endothelin-1 in human endometrium and myometrium during each menstrual phase.

STUDY DESIGN

Materials were obtained at hysterectomy (endometrium, n = 33; myometrium, n = 27). We measured immunoreactive endothelin-1 and immunoreactive big endothelin-1 by radioimmunoassay and performed an immunohistochemical study of the tissue. Data were analyzed by the Mann-Whitney U test.

RESULTS

We detected larger amounts of immunoreactive endothelin-1 and immunoreactive big endothelin-1 in the endometrium than in the myometrium throughout the menstrual, proliferative, and secretory phases. Endometrial immunoreactive endothelin-1 and immunoreactive endothelin-1 were significantly increased in the menstrual phase (endothelin-1 68.8 +/- 23.3 pg/mg protein, n = 5, p < 0.005; big endothelin-1 45.2 +/- 5.7 pg/mg protein, n = 5, p < 0.003) compared with the other phases (endothelin-1 30.7 +/- 9.5 and 30.5 +/- 14.0 pg/mg protein; big endothelin-1 19.9 +/- 6.7 and 24.1 +/- 7.4 pg/mg protein). Immunohistochemistry demonstrated that the endometrial stromal cells were positive for antiendothelin monoclonal antibody only in the premenstrual and menstrual phases.

CONCLUSION

Levels of immunoreactive endothelin-1 and immunoreactive big endothelin-1 are different in each type of uterine tissue and in each phase of the menstrual cycle. These changes may indicate some role of endothelin-1 in menstruation.

SCG10, a neuron-specific growth-associated protein in Alzheimer's disease

Neuronal growth-associated proteins (nGAPs) are markers of neuronal process outgrowth and are associated with both degenerative and sprouting responses in Alzheimer's disease (AD) brain. To study possible involvement of SCG10, an nGAP, in AD, we cloned human SCG10 cDNA and analyzed SCG-10 at mRNA and protein levels in control and AD brains. The deduced amino acid sequence of human SCG10 was 69% identical to stathmin, another nGAP. By in situ hybridization, both SCG10 and stathmin mRNAs were detected in selected neuronal populations in aged human brains. Quantitative analysis by RNase protection revealed that levels of neither SCG10 nor stathmin mRNAs were significantly altered in AD. Using an SCG10-specific antibody, Western blot analysis did not reveal any quantitative changes of SCG10 in AD. However, when the concentration of SCG10 protein was plotted against the number of tangles, a positive correlation was found. SCG10 levels did not correlate with plaque numbers. Furthermore, immunohistochemical study revealed that neuronal SCG10 protein accumulated in the cell bodies in AD-affected regions. Thus, SCG10 compartmentalization and metabolism may be altered in AD possibly due to mechanisms related to tangle formation in this disease.

Human T-cell leukemia virus type I tax transactivates the interleukin-6 gene in human rheumatoid synovial cells

OBJECTIVE

To determine the effect of the human T cell leukemia virus type I (HTLV-I) tax gene on interleukin-6 (IL-6) production and gene transcription in synovial cells, we established the synovial cell line, E-11, from a patient with rheumatoid arthritis.

METHODS

E-11 cells were transfected with tax expression vector using the calcium phosphate coprecipitation method. IL-6 production and gene expression were investigated by ELISA and Northern blot analysis, respectively. To clarify how tax induces IL-6 gene expression, we used deletion analysis and chloramphenicol acetyltransferase (CAT) assay, and electrophoretic mobility shift assay (EMSA).

RESULTS

Transfection of the tax gene induced markedly high levels of IL-6 mRNA. Furthermore, the tax gene strongly transactivated IL-6 gene promoter activity assayed by CAT assay. By using deletion and site specific mutations, we have identified a nuclear factor (NF)-kappa B sequence (positions -73 to -63) which is essential for tax transaction. EMSA demonstrated the induction of specific binding of nuclear extracts to the NF-kappa B sequence by HTLV-I tax.

CONCLUSION

The HTLV-1 tax gene may transactivate IL-6 gene in the synovial cells through NF-kappa B and may contribute in the pathophysiology of HTLV-I associated arthritis.

Mutations of the p53 gene in myelodysplastic syndrome and overt leukemia

We analysed p53 mutations in 24 patients with myelodysplastic syndrome (MDS) and overt acute myeloid leukaemia after a period of MDS, using polymerase chain reaction-single strand conformation polymorphism analysis. In exons 5 to 8, mobility shifts were detected in five of the 24 patients. Sequence analysis was subsequently performed, and four missense mutations (16.7%) and one silent nucleotide substitution were identified. Patients harbouring mutations were characterized as having advanced disease. Loss of the wild type allele was observed in three of the four patients with missense mutations. No mobility shifts of the N-ras or FMS gene were detected in these four patients. We next analysed the correlation of the p53 mutations with the progression of MDS in three patients. The mutation was accompanied by the progression in two of the three patients. These findings suggest that mutations of the p53 gene are associated with progression in some cases of MDS, while being compatible with stable disease or clonal evolution in others.

Cloning, expression, and chromosomal localization of a novel cadherin-related protein, protocadherin-3

To study the diversity of the protocadherin family, the cDNA clones for a novel protocadherin were isolated by screening rat brain cDNA libraries with a cDNA fragment obtained by PCR, and some of the properties were then characterized. The overall structure of the protein defined by the clone is similar to that of previously identified protocadherins; however, the cytoplasmic domain is distinct from those of previously cloned protocadherins or any other protein sequences in the data bank. We named this protocad herin-3 (Pcdh3) since this is the third protocadherin of which the entire coding sequence has been determined. Most of the deduced amino acid sequences of other cDNA clones obtained by the screening show high homology with but are distinct from that of Pcdh3, indicating that most of these sequences correspond to homologous but different protocadherins. These results demonstrate that Pcdh3 and the protocadherins defined by these clones constitute a protocadherin subfamily. Chromosome mapping indicates that mouse Pcdh3 is located in a specific region of mouse chromosome 18, close to the location of previously cloned protocadherins, suggesting that various protocadherins form a cluster in this region. In situ hybridization results showed that Pcdh3 and its related proteins were expressed at various areas in brain. The expressed Pcdh3 protein from the cDNA in mouse L cells was about 100 kDa in molecular weight and was localized at cell-cell contact sites. In contrast to the classical cadherins, however, the expressed Pcdh3 was sensitive to trypsin even in the presence of Ca2+, and the transfectants did not show strong Ca(2+)-dependent cell aggregation activity. These results indicate the structural and possibly functional diversity of the protocadherin family and suggest a distinctive biological role for Pcdh3.

CD34-positive blastoma in a patient with idiopathic myelofibrosis

We report CD34-positive "blastoma" which developed in a patient with idiopathic myelofibrosis (IMF). A 48-year-old woman was diagnosed as having essential thrombocythemia, then the disease had transformed into IMF 41 months later. Finally, a subcutaneous tumor, composed of blastic cells positive for CD34 but negative for lineage-specific antigens, developed without any evidence of systemic leukemia transformation.

Role of ATP-sensitive K+ channels in anoxia-sensitive negative potential of endolymph

To investigate the possible role of the ATP-sensitive K+ channels (KATP channels) in the generation of the anoxia-sensitive negative potential (ASNP), the effects of the treatment with glybenclamide and diazoxide on the endocochlear potential (EP) and K+ activity (AK) in the scala media were examined with double-barrelled K(+)-selective microelectrodes. The experiments were carried out in guinea pig cochleae, using glybenclamide as a KATP channel blocker and diazoxide as a KATP channel opener. Perilymphatic perfusion of glybenclamide decreased the amplitude of the ASNP and shortened its duration, whereas perfusion of diazoxide increased ASNP amplitude and prolonged its duration. Glybenclamide enhanced the decrease of endolymphatic AK by anoxia, whereas diazoxide suppressed this AK decrease. The results suggest that KATP channels may be involved in the generation of the ASNP.

Different effect of hippocampal granule cell destruction on amygdaloid kindling in Sprague-Dawley and Wistar rats

The hippocampal granule cells receive major inputs via the perforant path from other limbic structures such as the amygdala (AM). In this study, we examined Sprague-Dawley (SD) and Wistar rats, the effect of bilateral destructions of the hippocampal granule cells on the process of AM kindling and kindled AM seizures after completion of kindling. The granule cells were selectively and completely destroyed bilaterally by intra-hippocampal injections of colchicine. The left AM was used as the primary kindling site and the right AM as the secondary site. In SD rats, prior destruction of the granule cells caused a marked delay in the seizure development of both the primary AM kindling and subsequent secondary AM kindling. However, once AM kindling was established in SD rats, the destruction of granule cells was totally ineffective in preventing kindled seizures. In Wistar rats, unlike SD rats, prior destruction of the granule cells failed to change the rate of kindling at the primary and secondary sites. However, Wistar rats showed a transient and marked regression of kindled seizures when the granule cells were destroyed after the completion of AM kindling. In both strains, granule cell destruction had no effect on the re-establishment of kindled seizures at the time of primary-site re-test. These findings suggest that hippocampal granule cells of SD and Wistar rats play different roles in AM kindling.

Effect of intravenously applied canrenoate on ampullar endolymphatic potential

The effect of canrenoate, an aldosterone antagonist, on the ampullar endolymphatic potential (AEP) was examined to assess a possible role for aldosterone in the ampulla. Intravenous administration of canrenoate increased the AEP amplitude in a dose-dependent manner, with a significant reduction of the AEP negative component induced by anoxia. Pretreatment with aldosterone attenuated the AEP change produced by canrenoate. The results suggest that aldosterone may be involved in the modulation of ampullar function.

Anaplastic large cell lymphomas expressing the novel chimeric protein p80NPM/ALK: a distinct clinicopathologic entity

Anaplastic large cell lymphoma (ALCL) is a subtype of non-Hodgkin's lymphoma characterized by the CD30+ large neoplastic cells and sometimes carries a t(2;5)(p23;q35). Recently, we found a novel hyperphosphorylated 80-kD protein tyrosine kinase, p80, in ALCLs with t(2;5). Subsequent cDNA cloning showed p80 to be a fusion protein of two genes, the novel tyrosine kinase gene and the nucleophosmin gene, in accordance with the sequence of the NPM/ALK gene (Morris et al, Science 263:1281, 1994). Meanwhile, the clinicopathologic features of p80-carrying ALCLs have remained unclear. Paraffin sections of 105 cases of ALCL were immunostained using anti-p80 antibody, and 30 of them were shown to express p80. Clinicopathologic comparison between p80-positive and -negative ALCLs showed that p80-positive cases occurred in a far younger patient age group (16.2 +/- 12.9 years; p80-negative cases, 51.0 +/- 22.3 years; P < .0001) and the patients showed a far better 5-year survival rate (79.8%; p80-negative group, 32.9%; P < .01). These data showed that p80-positive ALCL is a distinct entity both clinically and pathogenetically and should be differentiated from p80-negative ALCL.

Production of interleukin 8 in adult T-cell leukemia cells: possible transactivation of the interleukin 8 gene by human T-cell leukemia virus type I tax

Interleukin 8 (IL-8) mRNA was detected in peripheral leukemic cells obtained from adult T-cell leukemia patients, as well as in cultured human T-cell leukemia virus type I (HTLV-I)-infected T-cell lines (HUT-102, MT-1, SALT-3, and SKT-1B). With the use of ELISA, IL-8 protein was also detected in the culture medium of these cells and in the extracellular fluids of patients. Furthermore, we demonstrated that the HTLV-I-derived transactivator protein, tax, could stimulate endogenous IL-8 gene expression in an uninfected T-cell line (Jurkat) and in a rheumatoid synovial cell line (E-11). Induction of IL-8 by tax at protein level was also demonstrated in transfected cells. We found that the IL-8 NF-kappa B-binding site specifically formed a complex with NF-kappa B-containing nuclear extracts from HTLV-I-infected T-cell lines and freshly isolated leukemic cells from adult T-cell leukemia patients. Finally, transfection of HTLV-I tax into Jurkat cells resulted in induction of specific binding of nuclear extracts to the NF-kappa B sequence. These results suggest that the HTLV-I tax gene may transactivate the IL-8 gene through the kappa B site in HTLV-I-infected cells and that constitutive expression of the IL-8 gene may play a role in HTLV-I-associated pathogenesis.

Interleukin-4 inhibits the production of interleukin-1 by adult T-cell leukemia cells

Freshly isolated leukemic cells from patients with adult T-cell leukemia (ATL) produce high levels of interleukin-1 (IL-1), which is believed to play an important role in neutrophilia, elevation of C-reactive protein, osteolytic bone lesions, hypercalcemia, and fever in ATL. However, relatively little is known regarding the regulatory mechanism of IL-1 production in ATL. Interleukin-4 (IL-4) affects the monocytes- and neoplastic cells-mediated cytokine production. In this study, we investigated the effect of IL-4 on IL-1 alpha and IL-1 beta production by ATL cells in vitro. IL-4 was found to markedly inhibit the release of IL-1 alpha and IL-1 beta into the conditioned medium in a dose-dependent manner. Northern blot analysis of steady-state IL-1 mRNA demonstrated that IL-4 treatment of ATL cells resulted in a reduction of IL-1 mRNA. These results support the notion that ATL cells spontaneously produce IL-1 alpha and IL-1 beta; however, such production can be inhibited by the immunomodulating agent, IL-4. IL-4 may play an important regulatory role in the production of IL-1 in ATL.

Plasma adsorption to charcoal and ion-exchange resin for treating postoperative hepatic failure

Postoperative hepatic failure was treated by plasma adsorption (PA) to charcoal and ion-exchange resin in five patients suffering from pancreatic or biliary carcinoma that was not accompanied by liver cirrhosis. Four of these patients recovered completely from the hepatic failure, while the fifth patient recovered sufficiently to be taken off the treatment for three weeks. Reactions in platelet counts and circulatory system during and after the PA treatment were minimal in all these patients. PA proved to be an effective liver support system for treating non-cirrhotic patients with postoperative hepatic failure.

Reduced expression of the molecular markers of dopaminergic neuronal atrophy in the aging rat brain

Expression of mRNAs encoding the dopamine transporter (DAT) and tyrosine hydroxylase (TH) in dopaminergic neurons of the substantia nigra (SN) was examined in young and aged Fischer 344 rats by in situ hybridization. Quantitative analysis revealed a statistically significant decline in both DAT and TH mRNA expression in 24-month-old rats in comparison to 6-month-old rats. In addition, it was noted that DAT mRNA expression tended to decrease by 18 months, while TH mRNA reduction did not occur until 24 months. The age-related loss of DAT and TH mRNA expressions was accompanied by diminished expression of mRNA for a neuronal growth-associated protein GAP-43, but not for SCG10 or alpha 1-tubulin. The loss of GAP-43 mRNA became evident when both DAT and TH gene expression declined with advanced age. Our findings indicate that DAT may be a marker of atrophy in dopamine neurons during normal aging.

Clinical evaluation of catheter-related fungemia and bacteremia

Forty-four patients with catheter-related infection admitted to Hokusho Central Hospital between 1985 and 1991 were studied retrospectively. The rate of catheter-related fungemia or bacteremia to all corresponding cases of fungemia and bacteremia increased from 7.7% in 1985 to 28.8% in 1991. The isolated pathogens were Candida parapsilosis (8 strains), Candida tropicalis (6 strains), methicillin-resistant Staphylococcus aureus (MRSA) (6 strains), methicillin-sensitive S. aureus (MSSA) (5 strains) and Streptococcus epidermidis (3 strains). Bacteremia occurred after catheterization of the femoral vein for a mean duration of 37 days. The period was significantly shorter than that after catheterization of the subclavian vein (56 days). The major isolates from the subclavian vein were Candida spp. (14/17, 82.4%), followed by MRSA (1/17, 5.9%) and MSSA (1/17, 5.9%), while isolates from the femoral vein were Candida spp. (6/16, 37.5%), MRSA (5/16, 31.3%) and MSSA (3/16, 20.8%). Catheter removal alone did not improve the clinical condition, particularly in MRSA bacteremia; the combination of antimicrobial therapy and removal of the catheter was necessary for a better prognosis.