Establishment and characterization of a CD95 (Fas/Apo-1)-negative myeloma cell line

Although expression of CD95 (Fas/Apo-1) on myeloma cells has been reported, its significance is not clearly understood. We established a myeloma cell line, KHM-11ad (11ad), from a parental cell line, KHM-11, by collecting cells adhered to a plastic dish. KHM-11 cells have been reported to be positive for CD45 and CD95 (Fas/Apo1), and negative for a myelomonocytic antigen, CD13. Interestingly, CD95 was not detected in 11ad. Expression of CD45 was also significantly decreased in 11ad cells while expression of CD13 was detected in these cells. The growth rate of 11ad cells was 1.7 times lower than that of KHM-11 cells. Analysis of adhesion molecules showed that expression of VLA4 and CD44 was significantly suppressed in 11ad. The IC50 of melphalan (L-PAM) for 11ad cells was 50 times higher than that for KHM-11, indicating that 11ad is significantly refractory to L-PAM than KHM-11 cells. Induction of apoptosis by doxorubicin and cycloheximide was suppressed in 11ad cells compared with those in KHM-11 cells. Western blot analysis for Bcl-2 family of proteins showed that Bax was expressed at a 2.2 times lower level in 11ad cells than in KHM-11 cells while there was no difference in expression of Bcl-2, Bcl-Xs nor Bcl-XL. These results suggest that CD95-negative myeloma cells may have characteristics as follows: (1) slow proliferation; (2) low sensitivity to apoptosis; (3) low expression of VLA4, CD44 and Bax. Although these intraclonal variations were based on the findings of cell lines, these may reflect similar variations in vivo. The 11ad line may be a suitable model for analyzing intraclonal variation of myeloma cells.

Induction of endothelial nitric-oxide synthase in rat brain astrocytes by systemic lipopolysaccharide treatment

In the brain, three isoforms of nitric oxide (NO) synthase (NOS), namely neuronal NOS (nNOS, NOS1), inducible NOS (iNOS, NOS2), and endothelial NOS (eNOS, NOS3), have been implicated in biological roles such as neurotransmission, neurotoxicity, immune function, and blood vessel regulation, each isoform exhibiting in part overlapping roles. Previous studies showed that iNOS is induced in the brain by systemic treatment with lipopolysaccharide (LPS), a Gram-negative bacteria-derived stimulant of the innate immune system. Here we found that eNOS mRNA is induced in the rat brain by intraperitoneal injection of LPS of a smaller amount than that required for induction of iNOS mRNA. The induction of eNOS mRNA was followed by an increase in eNOS protein. Immunohistochemical analysis revealed that eNOS is located in astrocytes of both gray and white matters as well as in blood vessels. Induction of eNOS in response to a low dose of LPS, together with its localization in major components of the blood-brain barrier, suggests that brain eNOS is involved in early pathophysiologic response against systemic infection before iNOS is induced with progression of the infection.

Expression of citrulline-nitric oxide cycle in lipopolysaccharide and cytokine-stimulated rat astroglioma C6 cells

Nitric oxide (NO) is involved in many physiological and pathological processes in the brain. NO is synthesized from arginine by nitric oxide synthase (NOS), with citrulline generated as a by-product of the reaction. Thus, citrulline can by recycled to arginine by argininosuccinate synthetase (AS) and argininosuccinate lyase (AL) via the citrulline-NO cycle. Rat astroglioma C6 cells were treated with bacterial lipopolysaccharide (LPS), interferon-gamma (IFNgamma) and tumor necrosis factor-alpha, and the expression of the enzymes of the citrulline-NO cycle was investigated by RNA blot and immunoblot analyses. NO production from arginine and citrulline was also assessed. iNOS mRNA and protein were induced 6-12 h after stimulation with LPS and cytokines and decreased at 24 h. AS mRNA increased up to 12 h and decreased at 24 h. AS protein increased gradually up to 48 h. On the other hand, AL mRNA remained unchanged by stimulation. NO production from arginine was enhanced by the treatment with LPS and cytokines. NO production was also observed when arginine was replaced by citrulline. These results indicate that NO production is enhanced in LPS- and cytokine-stimulated C6 cells due to induction of iNOS and that the citrulline-arginine recycling is important for NO production.

Expression of inducible nitric oxide synthase and enzymes of arginine metabolism in Fusarium kyushuense-exposed mouse lung

Expression of inducible nitric oxide (NO) synthase (iNOS) and related enzymes of arginine metabolism in the mouse lung exposed to filamentous fungus Fusarium kyushuense was studied by RNA blot, immunoblot, and histological analyses. When mice were exposed intranasally to the fungi only once, no induction of iNOS mRNA was observed. However, when the animals were infected again 6 days after the first exposure, iNOS mRNA was induced, reached a maximum 12-24 h after the exposure, and decreased to an undetectable level at 48 h. mRNAs for cationic amino acid transporter-2 (CAT2) and argininosuccinate synthetase were induced gradually, reached a maximum at 24 h, and decreased at 48 h. Arginase II mRNA increased at 24 h and decreased markedly at 48 h. On the other hand, arginase I mRNA started to increase at 24 h and reached to a much higher level at 48 h. Ornithine decarboxylase and ornithine aminotransferase mRNAs were also induced. Immunoblot analysis showed that iNOS, argininosuccinate synthetase, and arginase I and II proteins were induced with similar kinetics as those of their respective mRNAs. In histological examination, fungal elements were observed in the bronchoalveolar lumen at 3-6 h, decreased at 12 h, and almost disappeared at 48 h. Small granuloma appeared 3 h after the infection and their size increased with time. These results suggest that NO is produced in the mouse lung in response to F. kyushuense exposure and that the NO production is regulated by CAT2, the citrulline-NO cycle, and arginase isoforms. Enhanced synthesis of polyamines and proline (and thus collagen) is also suggested.

Regulation of the genes for arginase isoforms and related enzymes in mouse macrophages by lipopolysaccharide

Arginase exists in two isoforms, the hepatic (arginase I) and extrahepatic types (arginase II). Arginase I is markedly induced in rat peritoneal macrophages and rat tissues in vivo by bacterial lipopolysaccharide (LPS). In contrast, both arginase I and arginase II are induced in LPS-activated mouse peritoneal macrophages. In the present study, expression of arginase isoforms and related enzymes was studied in mouse tissues in vivo and in peritoneal macrophages with RNA blot and immunoblot analyses and enzyme assay. When mice were injected intraperitoneally with LPS, inducible nitric oxide synthase (iNOS) and arginase II were induced early in the lung and spleen. mRNAs for argininosuccinate synthase (AS) and ornithine decarboxylase (ODC) were also induced early. In comparison, arginase I was induced later in the lung. Early induction of iNOS, arginase II, AS, ODC, and cationic amino acid transporter 2 and late induction of arginase I were observed in LPS-activated peritoneal macrophages. These results indicate that the genes for the two arginase isoforms are regulated differentially. Possible roles of the arginase isoforms in the regulation of nitric oxide production and in polyamine synthesis are discussed.

Detection of inducible nitric oxide synthase (iNOS) mRNA by RT-PCR in ATL patients and HTLV-I infected cell lines: clinical features and apoptosis by NOS inhibitor

Various tumors have been reported to express an inducible form of nitric oxide synthase (iNOS), and nitric oxide (NO) may affect the clinicopathological features of these tumors. Previously, Burkitt's lymphoma and Epstein-Barr virus (EBV)-infected cells were shown to express iNOS constitutively at a low level. We analyzed iNOS expression by the reverse transcriptase-polymerase reaction method (RT-PCR) in eight HTLV-I-infected cell lines (five were ATL-derived lines and there were in vitro transformed lines), nine ATL patients (three were chronic, two were acute, and four were lymphoma type), and an HTLV-I-negative T cell line (CEM). In four ATL derived and in all three in vitro transformed cell lines, iNOS was expressed constitutively, but it was not expressed in CEM cells. Four out of nine ATL patients also showed iNOS expression. The expression of iNOS was found in all subtypes of ATL. Three of four iNOS-positive patients had infiltration of ATL cells to organs such as skin, lung, or liver. In NOS inhibitor (NG-monomethyl-L-arginine: L-NMMA)-containing medium, an iNOS-positive ATL cell line (K3T) showed growth inhibition and DNA ladder. Although only a limited number of patients was analyzed, our results suggest that NO may be involved in the invasive character of ATL cells. The NOS inhibitor can induce apoptosis in an ATL cell line, as it does in EBV-infected cell lines.

Analysis of 1,992 patients with anorectal malformations over the past two decades in Japan. Steering Committee of Japanese Study Group of Anorectal Anomalies

BACKGROUND/PURPOSE

This report describes the results of a group study of the Japanese Study Group of Anorectal Anomolies (JSGA) to determine the relative incidence of specific types of anorectal anomaly in Japan, and includes discussion of rectourethral fistula regarding the relationship between the levels of the fistula and blind end of the rectum, low type deformity, rare types, and associated anomalies.

METHODS

A total of 1,992 patients (1,183 boys and 809 girls) registered from 1976 to 1995 were analyzed.

RESULTS

High-type deformities accounted for 26.0% of cases, intermediate 10.7%, low 57.2%, miscellaneous 4.5% and unclassified 1.8%. The most frequent deformity was male anocutaneous fistula (n = 364), followed by male rectourethral fistula (n = 333), and female anovestibular fistula (n = 241). There were 42 rectovesical fistulas in boys and 93 rectocloacal fistulas in girls. Covered anus complete occurred at the same frequency (10.1% of low deformities) as covered anal stenosis. In rectourethral fistula, the blind end of the rectum lay at or above the level of the P-C line in 40.3% of cases, at or above the M line in 39.6% and at the vicinity of the I line in 20.2%, respectively. There was no parallel relationship between the site of the fistula opening and the level of the rectal pouch. The overall incidence of patients having one or more associated anomalies was 45.2%: 70.6% in high deformity, 60.7% in intermediate, and 31.3% in low. The rate of association of Down's syndrome with deformities without fistula (40.3%) was significantly higher than with deformities with fistula (0.3%).

CONCLUSIONS

Rectovesical fistula and covered anus complete were not infrequent deformities in this series. We consider that at least 20% of rectourethral fistula should be categorized as intermediate or low deformity from the viewpoint of the position of the rectal pouch. A significant preponderance of Down's syndrome in the deformities without fistula suggests that further investigation of associated anomalies in comparision with other congenital diseases may provide insights into the pathogenesis of anorectal malformation in the field of molecular genetics.

Expression of arginase II and related enzymes in the rat small intestine and kidney

Arginase, which catalyzes the conversion of arginine to urea and ornithine, and consists of a liver-type (arginase I) and a non-hepatic type (arginase II). Arginine is also used for the synthesis of nitric oxide and creatine phosphate, while ornithine is used for the synthesis of polyamines and proline, and thus collagen. Arginase II mRNA and protein are abundant in the intestine (most abundant in the jejunum and less abundant in the ileum, duodenum, and colon) and kidney of the rat. In the kidney, the levels of arginase II mRNA do not change appreciably from 0 to 8 weeks of age. In contrast, arginase II mRNA and protein in the small intestine are not detectable at birth, appear at 3 weeks of age, the weaning period, and their levels increase up to 8 weeks. On the other hand, mRNAs for ornithine aminotransferase (OAT), ornithine decarboxylase, and ornithine carbamoyltransferase (OCT) are present at birth and their levels do not change much during development. Arginase II is elevated in response to a combination of bacterial lipopolysaccharide, dibutyryl cAMP, and dexamethasone in the kidney, but is not affected by these treatments in the small intestine. Immunohistochemical analysis of arginase II, OAT, and OCT in the jejunum revealed their co-localization in absorptive epithelial cells. These results show that the arginase II gene is regulated differentially in the small intestine and kidney, and suggest different roles of the enzyme in these two tissues. The co-localization of arginase II and the three ornithine-utilizing enzymes in the small intestine suggests that the enzyme is involved in the synthesis of proline, polyamines, and/or citrulline in this tissue.

Expression of PRAD1/cyclin D1 in plasma cell malignancy: incidence and prognostic aspects

We analysed PRAD1/cyclin D1 expression in 20 patients with plasma cell malignancy by Northern analysis. 6/17 multiple myeloma patients and 3/3 plasma cell leukaemia patients showed PRAD1/cyclin D1 expression. This incidence appeared to be higher than the expected incidence based on previous studies. Southern analysis did not show rearrangement of the bcl-1 region. Although there was no statistical difference, the PRAD1/cyclin D1 negative group showed a 1-year survival of 81.8%, 3-year survival of 45.5% and 5-year survival of 22.7%, and those for the PRAD1/cyclin D1 positive group were 63.5%, 16.9% and 16.9%, respectively. Further study is required to determine whether PRAD1/cyclin D1 expression is a prognostic factor.

Establishment of a monoclonal antibody to human myeloma cell: relation to chemotherapy and extramedullar infiltration

Resistance of myeloma cells to melphalan (L-PAM) is a serious problem. To investigate mechanisms of drug resistance, we generated a monoclonal antibody, clone O3, to melphalan-resistant myeloma cells, KHM-11R. Western blot analysis showed that molecular weight of O3 antigen was approximately 90 kDa. Expression of O3 antigen was approximately two times higher in KHM-11R than in parental melphalan sensitive cell line, KHM-11. O3 was preferentially expressed in plasma cell, B-cell, and monocytic cell lines, but not in T-cell lines. Analysis of bone marrow samples from myeloma patients revealed that 13 of 23 samples expressed O3 antigen at various levels, and that O3 antigen expression in patients correlate with preceding chemotherapy, advanced clinical stage and extramedullar invasion of myeloma cells. Furthermore, patients expressing O3 antigen at the time of diagnosis tended to have poor prognosis. The investigation of O3 antigen in myeloma cells will be useful to reveal the pathophysiology of extramedullar invasion and the mechanism of cell killing by melphalan.

Expression of Bcl-2 family of proteins in fresh myeloma cells

Members of the Bcl-2 family of proteins, Bcl-2, Bcl-X(L), Bcl-Xs and Bax, are considered to play important roles in the regulation of apoptosis and drug resistance. To understand the significance of these proteins in fresh human myeloma cells, expression of Bcl-2 family of proteins was analyzed by Western blotting in 17 cases with multiple myeloma (MM) and three cases with plasma cell leukemia (PCL). Bcl-2 and Bcl-X(L) were found in 12 and nine samples, respectively. All PCL cases showed co-expression of Bcl-2 and Bcl-X(L). Analysis of MM cases showed that Bcl-2 was preferentially expressed in samples from cases with early clinical stage while Bcl-X(L) tended to be expressed in samples from cases at advanced clinical stage. Bcl-X(L) was significantly expressed in tumor cells from cases with extramedullar lesions. There was no correlation between the expression levels of Bcl-2 or Bcl-X(L) and preceding chemotherapy. Expression of Bax was found in only one patient who had pleural effusion caused by invasion of myeloma cells and a high serum LDH level. Survival analysis revealed that there was no statistical significance in expression of Bcl-2 or Bcl-X(L) although Bcl-X(L) tended to be expressed in cases with poor prognosis. These findings indicate that expression of Bcl-2 family of proteins is heterogeneously regulated in fresh myeloma cells. Expression of Bcl-X(L) and Bcl-2 may correlate with extramedullar invasion and early stage of the disease, respectively. Absence of Bax in myeloma cells may contribute to low sensitivity of myeloma cells to anti-cancer agents since Bax is reported to mediate cytotoxicity of some anti-cancer drugs.

Immunohistochemical localization of arginase II and other enzymes of arginine metabolism in rat kidney and liver

Arginine is a precursor for the synthesis of urea, polyamines, creatine phosphate, nitric oxide and proteins. It is synthesized from ornithine by argininosuccinate synthetase and argininosuccinate lyase and is degraded by arginase, which consists of a liver-type (arginase I) and a non-hepatic type (arginase II). Recently, cDNAs for human and rat arginase II have been isolated. In this study, immunocytochemical analysis showed that human arginase II expressed in COS-7 cells was localized in the mitochondria. Arginase II mRNA was abundant in the rat small intestine and kidney. In the kidney, argininosuccinate synthetase and lyase were immunostained in the cortex, intensely in proximal tubules and much less intensely in distal tubules. In contrast, arginase II was stained intensely in the outer stripes of the outer medulla, presumably in the proximal straight tubules, and in a subpopulation of the proximal tubules in the cortex. Immunostaining of serial sections of the kidney showed that argininosuccinate synthetase and arginase II were colocalized in a subpopulation of proximal tubules in the cortex, whereas only the synthetase, but not arginase II, was present in another subpopulation of proximal tubules. In the liver, all the enzymes of the urea cycle, i.e. carbamylphosphate synthetase I, ornithine transcarbamylase, argininosuccinate synthetase and lyase and arginase I, showed similar zonation patterns with staining more intense in periportal hepatocytes than in pericentral hepatocytes, although zonation of ornithine transcarbamylase was much less prominent. The implications of these results are discussed.

Dictyostelium TRFA homologous to yeast Ssn6 is required for normal growth and early development

The TPR (tetratricopeptide repeat) family became widespread during evolution, having been found from bacteria to mammals. By means of restriction enzyme-mediated integration, we have identified a Dictyostelium gene (trfA) highly homologous to a Saccharomyces cerevisiae gene encoding a TPR protein, Ssn6 (Cyc8), which functions as a global transcriptional repressor for diverse genes. The deduced amino acid sequence of the Dictyostelium gene product, TRFA, contains 10 consecutive TPR units as well as Gln repeats, Asn repeats, and a region rich in Glu, Lys, Ser, and Thr. The sequences of some of the 10 TPR units in TRFA are more than 70% identical to the corresponding units in Ssn6. The trfA- cells produced smooth plaques on a bacterial lawn and failed to aggregate normally when starved on a plain agar plate. Individual trfA- cells also failed to correctly respond to cAMP, although the adenylyl cyclase of trfA- cells was expressed upon starvation and activated by stimulation with cAMP as in the wild-type cells. When cultured in a rich medium in suspension, they grew more slowly and stopped growing at a lower density than the wild-type cells. Furthermore, they divided into cells of various sizes and tended to be much smaller than the wild-type cells. These pleiotropic defects of the trfA- cells suggest the possibility that Dictyostelium TRFA may regulate the transcription of diverse genes required for normal growth and early development.

Evaluation of hair root analysis for acute phencyclidine poisoning and behavior of phencyclidine metabolites in rat hair root

We evaluated the usefulness of hair root analysis to diagnose acute phencyclidine (PCP) poisoning. Male rats were i.p. administered acute poisonous doses (80, 100 and 120 mg/kg) of PCP hydrochloride and the hair roots were plucked out with hair nippers at certain times after administration. The hair root samples were extracted with methanol/HCl. After evaporation of the solvent, the residue was derivatized with N,O-bis(trimethylsilyl) acetamide and analyzed with GC/MS. PCP was detected at high concentrations (up to 181.7 ng/mg) from all samples. The peak concentrations at every dose were observed at 6 h. The concentrations of PCP in the rat hair roots increased dose-dependently in the range of the doses. 1-(1-Phenylcyclohexyl)-4-hydroxypiperidine (PCHP) and trans-1-phenyl-1(4'-hydroxypiperidino)-4-cyclohexanol (t-PCPdiol) were also detected from 5 and 15 min to 48 h after administration, respectively. It is concluded that hair root is a useful specimen for the diagnosis of acute PCP poisoning because PCP, PCHP and t-PCPdiol are detected very soon after administration and a large amount of them is retained in hair root for a long time. PCHP was found from the early stage in hair roots and its concentration was higher than that of t-PCPdiol for 6 h. However, the concentration of t-PCPdiol became higher than that of PCHP after 6 h. These phenomena could be explained by the time lag of production of the primary (PCHP) and the secondary metabolite (PCPdiol).

A novel Dictyostelium discoideum gene required for cAMP-dependent cell aggregation

Using a method of random insertional mutagenesis called REMI (restriction enzyme-mediated integration), we isolated two mutant strains of Dictyostelium discoideum with a defect in cAMP-dependent cell aggregation. On bacterial lawns, both of the cells formed large and smooth plaques. When starved in a non-nutrient medium, they became elongated and extended pseudopods very frequently like starved wild type cells. However, they never formed streams toward an aggregation center. Genomic DNA fragments flanking the sites of insertion of the REMI tag were rescued from the mutant cells. The fragments contained one common open reading frame encoding a protein of 1148 amino acid residues. The protein's sequence is homologous to those of two hypothetical proteins of S. cerevisiae and S. pombe.

Multiple myeloma associated with serum amino acid disturbance and high output cardiac failure

We experienced a plasma cell leukemia (PCL) patient complicated with high output cardiac failure (HOCF), proved as his elevated cardiac index and pulmonary artery wedge pressure and decreased systemic vascular resistance index in a hemodynamic study. We found no possible causes of HOCF. Interestingly, HOCF was improved as PCL responded to intensive chemotherapy. On the other hand, he showed consciousness disturbance, and had frequent attacks of generalized seizure. His electroencephalogram showed slow waves, and a spike and wave complex. Hyperammonemia and abnormal amino acid distribution were also found. This abnormal serum amino acid distribution, especially elevated glycine level, was different from that seen in chronic liver failure, and he had no hepatic disease. After intensive chemotherapy, the serum ammonia level and glycine level decreased. In this patient, PCL seemed to be responsible for HOCF, hyperammonemia, and abnormal amino acid distribution. We experienced two more cases of multiple myeloma (MM) with HOCF, hyperammonemia, abnormal serum amino acid distribution, and consciousness disturbance of unknown origin. Those two cases showed slow waves in the electroencephalogram. Improvement was seen in their HOCF, hyperammonemia, and abnormal amino acid levels after chemotherapy. The possibility of MM as a cause of HOCF is discussed.

Regulation of the urea cycle enzyme genes in nitric oxide synthesis

Nitric oxide (NO) is synthesized from arginine by nitric-oxide synthase (NOS), and citrulline that is generated can be recycled to arginine by argininosuccinate synthase (AS) and argininosuccinate lyase (AL). Rats were injected with bacterial lipopolysaccharide (LPS) and expression of the inducible isoform of NOS (iNOS), AS and AL was analysed. In RNA blot analysis, iNOS mRNA was induced by LPS in the lung, heart, liver and spleen, and less strongly in the skeletal muscle and testis. AS and AL mRNAs were induced in the lung and spleen. Kinetic studies showed that iNOS mRNA increased rapidly in both spleen and lung, reached a maximum 2-5 h after the treatment, and decreased thereafter. On the other hand, AS mRNA increased more slowly and reached a maximum in 6-12 h (by about 10-fold in the spleen and 2-fold in the lung). AL mRNA in the spleen and lung increased slowly and remained high up to 24 h. In immunohistochemical analysis, macrophages in the spleen that were negative for iNOS and AS before LPS treatment were strongly positive for both iNOS and AS after this treatment. As iNOS, AS and AL were co-induced in rat tissues and cells, citrulline-arginine recycling seems to be important in NO synthesis under the conditions of stimulation. Arginine is a common substrate of NOS and arginase. Rat peritoneal macrophages were cultured in the presence of LPS and expression of iNOS and livertype arginase (arginase I) was analysed. mRNAs for iNOS and arginase I were induced by LPS in a dose-dependent manner. iNOS mRNA appeared 2 h after LPS treatment and increased up to a near-maximum at 8-12 h. On the other hand, arginase I mRNA began to increase after 4 h with a lag time and reached a maximum at 12 h. Immunoblot analysis showed that iNOS and arginase I proteins were also induced. Induction of iNOS and arginase I mRNAs were also observed in LPS-injected rats in vivo. Thus, arginase I appears to have an important role in downregulating NO synthesis in murine macrophages by decreasing the availability of arginine. A cDNA for human arginase II, an arginase isozyme, was isolated. A polypeptide of 354 amino acid residues including the putative NH2-terminal presequence for mitochondrial import was predicted. It was 59% identical with arginase I. mRNA for human arginase II was present in the kidney and other tissues but was not detected in the liver. Arginase II mRNA was co-induced with iNOS mRNA in murine macrophage-like RAW 264.7 cells by LPS. This induction was enhanced by dexamethasone and dibutyrul cAMP, and was prevented by interferon-gamma. These results indicate that NO synthesis is regulated by arginine-synthesizing and -degrading enzymes in a complicated manner.

Hyperdiploid myeloma cell as an indicator of poor prognosis and drug refractoriness

Although almost 40% of patients with multiple myeloma respond to initial chemotherapy, myeloma with no response to initial chemotherapy remains a serious problem. To understand the characteristics of drug-refractoriness of myeloma, fresh tumor cells from 13 untreated myeloma patients were fixed and stained with anti-human immunoglobulins and propidium iodide for subsequent flow cytometric analysis of DNA content. More than 10% of myeloma cells were hyperdiploid in eight cases (hyperdiploid + cases) while less than 10% of myeloma cells were hyperdiploid in five cases (hyperdiploid - cases). The proportion of hyperdiploid cells among all myeloma cells was highly correlated with incidence of myeloma cells with morphologically abnormal nuclei such as those with multiple-nuclei or convoluted nuclei (P = 0.001). Among the eight hyperdiploid + cases, two (2/8) showed good response to subsequent chemotherapy while four of five hyperdiploid - cases (4/5) responded well. Cases with poor response had more hyperdiploid myeloma cells (average 25.7% of all myeloma cells) than sensitive cases (average 6.8%), suggesting a contribution of hyperdiploid myeloma cells to primary drug resistance (P = 0.065). The 3 year survival rate of hyperdiploid+cases was 0% while that of the control group was 41.9%. These results suggest that myeloma cells with abnormal nuclear morphology may show hyperdiploidy and poor response to chemotherapy.

Acetylcholinesterase (ACE) staining shows the abnormal innervation of a pulled-through rectum in a case of repaired anorectal malformation

Abnormal innervation of the anorectum was noted in relation to anal incontinence in a case of repaired high-type anorectal malformation (ARM). A ten-year-old boy presented with anal incontinence after reconstructive surgery of ARM with a recto-urethral fistula. An anorectal manometrical examination revealed both an adequate tonus of the anal sphincter muscles and the absence of rectoanal reflex relaxation. And a barium enema showed a narrow region in the rectosigmoid colon, which was similar to that of Hirschsprung's disease (HD). Furthermore, an acetylcholinesterase (ACE) histochemical study of the rectal suction biopsies revealed an increased number of ACE-positive nerve fibers in the lamina propria mucosae and muscularis mucosae of the pulled-through colon. At the same time, however, some ganglia cells were also observed in the submucosa of the affected rectosigmoid colon and these cells could not be found in HD. Although the mechanism by which the abnormally innervated parasympathetic nerve fibers arose in the pulled-through colon remains unclear, this neuronal abnormality is considered to be the cause of anal incontinence in this case.

Coinduction of nitric-oxide synthase and arginase I in cultured rat peritoneal macrophages and rat tissues in vivo by lipopolysaccharide

Nitric oxide is synthesized by nitric-oxide synthase from arginine, a common substrate of arginase. Rat peritoneal macrophages were cultured in the presence of bacterial lipopolysaccharide (LPS), and expression of the inducible isoform of nitric-oxide synthase (iNOS) and liver-type arginase (arginase I) was analyzed. mRNAs for iNOS and arginase I were induced by LPS in a dose-dependent manner. iNOS mRNA appeared 2 h after LPS treatment and increased to a near maximum at 8-12 h. On the other hand, arginase I mRNA that was undetectable prior to the treatment began to increase after 4 h with a lag time and reached a maximum at 12 h. Immunoblot analysis showed that iNOS and arginase I proteins were also induced. mRNA for arginase II, an arginase isozyme, was not detected in the LPS-activated peritoneal cells. mRNA for CCAAT/enhancer-binding protein beta (C/EBPbeta), a transactivator of the arginase I gene, was also induced, and the induction was more rapid than that of arginase I mRNA. Changes in iNOS and arginase I mRNAs were also examined in LPS-injected rats in vivo. iNOS mRNA increased rapidly in the lung and spleen, reached a maximum 2-6 h after the LPS treatment, and decreased thereafter. Arginase I mRNA was induced markedly and more slowly in both tissues, reaching a maximum in 12 h. Thus, arginase I appears to have an important role in down-regulating nitric oxide synthesis in murine macrophages by decreasing the availability of arginine, and the induction of arginase I is mediated by C/EBPbeta.

Molecular cloning of cDNA for nonhepatic mitochondrial arginase (arginase II) and comparison of its induction with nitric oxide synthase in a murine macrophage-like cell line

Arginase exists in two isoforms. Liver-type arginase (arginase I) is expressed almost exclusively in the liver and catalyzes the last step of urea synthesis, whereas the nonhepatic type (arginase II) is expressed in extrahepatic tissues. Arginase II has been proposed to play a role in down-regulation of nitric oxide synthesis. A cDNA for human arginase II was isolated. A polypeptide of 354 amino acid residues including the putative NH2-terminal presequence for mitochondrial import was predicted. It was 59% identical with arginase I. The arginase II precursor synthesized in vitro was imported into isolated mitochondria and proteolytically processed. mRNA for human arginase II was present in the kidney and other tissues, but was not detected in the liver. Arginase II mRNA was coinduced with nitric oxide synthase mRNA in murine macrophage-like RAW 264.7 cells by lipopolysaccharide. This induction was enhanced by dexamethasone and dibutyryl cAMP, and was prevented by interferon-gamma. Possible roles of arginase II in NO synthesis are discussed.

Interspecies reactivities of anti-human macrophage monoclonal antibodies to various animal species

We examined interspecies reactivities of eight anti-human monocyte/macrophage monoclonal antibodies (MAbs), Am-3K, PM-2K, X4, X14, Ber-MAC3, GHI/61, EBM/11, and KP1, with various animal tissues including rats, guinea pigs, rabbits, cats, dogs, goats, pigs, bovines, horses, and monkeys. All MAbs recognized monkey macrophages. Pig macrophages were detected by most MAbs except for EBM/11 and KP1. Of the eight antibodies, AM-3K showed the widest interspecies reactivity. It reacted with macrophages of all animal species examined, except for rats. Western blot analysis revealed a similarity in the antigens recognized by AM-3K among guinea pigs, rabbits, and humans. Other anti-human MAbs demonstrated distinct reactive patterns against macrophages in animals. The immunostaining patterns of all of these MAbs in animal tissues were similar to those found in humans, although some MAbs, such as AM-3K, EBM/11, and X4, displayed more restricted reactivity in animals than in humans. These results indicate that some anti-human monocyte/macrophage MAbs are also available for immunohistochemical detection of monocyte/macrophages in animal tissues. Among them, AM-3K is considered to be the most useful MAb for identifying macrophages in various tissues of animals.

Management of traumatic pancreatic pseudocysts in children

Eight children with pancreatic injuries after blunt abdominal trauma are presented. One patient with pancreatitis without complications was treated successfully with medication; seven (87.5%) developed pseudocysts, which resolved spontaneously with conservative treatment in four cases (57.1%). Non-resolving pseudocysts in 3 patients finally required surgical intervention. Pseudocysts that resolve spontaneously and those that require surgical intervention can be distinguished. The two groups showed different time sequences in both serum amylase values and pseudocyst size. Analyses of these clinical data revealed three factors with significant predictive value. On the basis of these findings, a new management strategy for traumatic pancreatic pseudocysts in children is proposed. The cyst is likely to resolve spontaneously in cases showing any two or more of the following factors: (1) cyst presentation after day 6; (2) maximum serum amylase below 1,600 IU/l; and (3) serum amylase below 600 IU/l on day 20. However, early surgical intervention is required in the presence of two or more of the following: (1) cyst presentation before day 4; (2) maximum serum amylase above 1,900 IU/l; or (3) serum amylase above 1,200 IU/l on day 20.

Urachal remnants

Although urachal remnants rarely are observed clinically, they often give rise to a number of problems such as fatal infection and late malignant changes. Therefore, a total assessment of the disease with a particular focus on embryology, anatomy, and clinical symptoms, as well as the most advisable treatment, is called for. The authors report on 33 previously experienced cases and discuss the problems involved in both the diagnosis and treatment of these anomalies.