Cloning, sequencing, and disruption of the Bacillus subtilis psd gene coding for phosphatidylserine decarboxylase

The psd gene of Bacillus subtilis Marburg, encoding phosphatidylserine decarboxylase, has been cloned and sequenced. It encodes a polypeptide of 263 amino acid residues (deduced molecular weight of 29,689) and is located just downstream of pss, the structural gene for phosphatidylserine synthase that catalyzes the preceding reaction in phosphatidylethanolamine synthesis (M. Okada, H. Matsuzaki, I. Shibuya, and K. Matsumoto, J. Bacteriol. 176:7456-7461, 1994). Introduction of a plasmid containing the psd gene into temperature-sensitive Escherichia coli psd-2 mutant cells allowed growth at otherwise restrictive temperature. Phosphatidylserine was not detected in the psd-2 mutant cells harboring the plasmid; it accumulated in the mutant up to 29% of the total phospholipids without the plasmid. An enzyme activity that catalyzes decarboxylation of 14C-labeled phosphatidylserine to form phosphatidylethanolamine was detected in E. coli psd-2 cells harboring a Bacillus psd plasmid. E. coli cells harboring the psd plasmid, the expression of which was under the control of the T7phi10 promoter, produced proteins of 32 and 29 kDa upon induction. A pulse-labeling experiment suggested that the 32-kDa protein is the primary translation product and is processed into the 29-kDa protein. The psd gene, together with pss, was located by Southern hybridization to the 238- to 306-kb SfiI-NotI fragment of the chromosome. A B. subtilis strain harboring an interrupted psd allele, psd1::neo, was constructed. The null psd mutant contained no phosphatidylethanolamine and accumulated phosphatidylserine. It grew well without supplementation of divalent cations which are essential for the E. coli pssA null mutant lacking phosphatidylethanolamine. In both the B. subtilis null pss and psd mutants, glucosyldiacylglycerol content increased two- to fourfold. The results suggest that the lack of phosphatidylethanolamine in the B. subtilis membrane may be compensated for by the increases in the contents of glucosyldiacylglycerols by an unknown mechanism.

Differences on intraoperative ultrasonography between meningioma and neurilemmoma

We examined the differences on intraoperative ultrasonography between 17 cases of meningioma and 29 of neurilemmoma, the common intradural extramedullary tumors. In meningiomas, cysts were rarely seen (in 12.5%, P < 0.01%) and echogenicity was high (in 82.3%, P < 0.01%). In neurilemmoma, many cysts were seen (72.5%) and low echoes tended to be more common (72.4%, P < 0.01%). In the neurilemmomas with high or isoechogenicity, Antoni A types, histologically rich in collagen fibres, predominated.

Multivariate analysis of the prognostic factors of patients with unresectable synchronous liver metastases from colorectal cancer

PURPOSE

It frequently is observed that widely varying prognoses are given for patients with the same extent of liver metastases from colorectal cancer, even though the same treatment is performed on these patients. One of the reasons for this variance is that prognostic factors for these patients have not been defined. This study was designed to elucidate which clinicopathologic factors were the most important in the prognosis of 73 patients with unresectable synchronous liver metastasis from colorectal cancer.

METHODS

Univariate and multivariate analysis of 11 clinicopathologic factors were performed using the Cox proportional hazard model. Survival curves were generated using the Kaplan-Meier method.

RESULTS

Extent of liver metastases was the most significant variable in this survival analysis, although the extent of lymph node metastases of the primary lesion also was significant. However, the method of treatment was not a significant determinant in the survival for patients with unresectable liver metastases. Median survival of patients with H1, H2, and H3 was 13, 12, and 6 months, respectively, and there was a significant difference between survival curves for patients with H1 and patients with H3. Median survival of patients with n0, n1, and n2 was 13, 7, and 7 months respectively, and there was a significant difference between survival curves for patients with n0 and patients with n2. Median survival of 6 patients with H1 and n0 and of 17 patients with H3 and n2 was 28 and 4 months, respectively. There was a significant difference in survival curves between these two groups.

CONCLUSION

Longevity of patients with unresectable synchronous liver metastases from colorectal cancer is affected adversely by the presence of nodal metastases and extent of liver metastases. This should be considered in the planning treatment.

High phosphorus diet rapidly induces nephrocalcinosis and proximal tubular injury in rats

The development of nephrocalcinosis and the time course of changes in kidney function, especially proximal tubular function, were studied in young male rats fed a high-phosphorus diet. The animals were fed a purified diet with a phosphorus content of either 0.5% (normal phosphorus diet) or 1.5% (high-phosphorus diet). In the group fed the high-phosphorus diet, nephrocalcinosis was found in 4 of 42 rats after 1 d of feeding and in all rats of this group at 3 d. The degree of nephrocalcinosis gradually increased with time. Upon histological observation by electron microscopy, vacuoles, lysosomes and swelling of microvilli in the proximal tubules were observed in rats fed the high-phosphorus diet after 1 d of feeding. Giant lysosomes with deposition of calcium and deposition of hydroxyapatite in mitochondria were observed in the proximal tubules of rats fed the high-phosphorus diet at 3 d. Albumin concentration in the urine of these rats was significantly increased at 3 d. The activity of N-acetyl-beta-D-glucosaminidase in the urine was also significantly increased after 1 d of feeding the high-phosphorus diet, and then reached a plateau. The beta 2-microglobulin concentration in the urine of rats fed the high-phosphorus diet was significantly increased at 14 d, and increased more toward 21 d. We concluded that nephrocalcinosis and injury to the proximal tubules are rapidly induced in rats fed a high-phosphorus diet.

Activation of protein kinase C by tyrosine phosphorylation in response to H2O2

Protein kinase C (PKC) isoforms, alpha, betaI, and gamma of cPKC subgroup, delta and epsilon of nPKC subgroup, and zeta of aPKC subgroup, were tyrosine phosphorylated in COS-7 cells in response to H2O2. These isoforms isolated from the H2O2-treated cells showed enhanced enzyme activity to various extents. The enzymes, PKC alpha and delta, recovered from the cells were independent of lipid cofactors for their catalytic activity. Analysis of mutated molecules of PKC delta showed that tyrosine residues, which are conserved in the catalytic domain of the PKC family, are critical for PKC activation induced by H2O2. These results suggest that PKC isoforms can be activated through tyrosine phosphorylation in a manner unrelated to receptor-coupled hydrolysis of inositol phospholipids.

[Evaluation of CTA for arterial infusion chemotherapy for liver metastasis from colorectal cancer]

To compare between the arterial blood supply of metastatic liver tumor and effects of intrahepatic arterial infusion chemotherapy (IHAC), we examined 8 patients with 27 liver metastasis from colorectal cancer. They were treated with ADM/lipiodol/5-FU/LV (19 nodules) or 5-FU/LV (8 nodules). To evaluate the arterial blood supply, CT arteriography (CTA) was performed, which classified tumors into 3 grades. Grade (Gr) 0; almost no enhancement, Gr1: less than one-third of tumor, Gr 2; less than two-thirds; Gr 3 over two-thirds (no case). As a result, 3 of NCs and 3 of PDs were Gr 0, 7 of MRs, 3 of NCs and 2 of PDs were Gr 1, and CR, PR and 7 of MRs were Gr 2. These results suggest that the arterial blood supply is necessary for a better response of IHAC and CTA is effective to forecast the response to IHAC.

[Arterial infusion chemotherapy in pelvic space for advanced rectal cancer]

Three rectal cancer patients were treated with arterial infusion chemotherapy through the internal iliac artery. Two patients with pelvic recurrences unresectable after APRA were treated with intensive chemotherapy and the other patient with neoadjuvant chemotherapy. In all cases, 5-FU (500 mg/ body/day) was administered continuously for 5 days or 14 days. We attempted three methods for this procedure which were a bilateral catheterization to the internal iliac artery, a single catheterization with an embolization to the other internal iliac artery and a single catheterization without the embolization. As the result of this treatment, in the resected specimen with neoadjuvant case, histological necrosis was found in 50% in the main tumor and the metastatic lymph nodes. One patient with pelvic recurrence showed a partial response in CT imaging, but died one year later of the recurrence around the external iliac artery. The other patient with pelvic recurrence treated with the bilateral catheterization had no efficacy on CT imaging, but his CEA level has decreased at present. It was concluded that arterial infusion chemotherapy was effective for advanced rectal cancer and the pelvic recurrences. However, the efficacy of this treatment is limited to the area to which the drugs are delivered. Thus, it is important that the method and the location of the catheterization are determined adequately for each case.

[Continuous hepatic arterial infusion of fluorouracil with leucovorin for liver metastases from colorectal cancer]

Sixteen patients with liver metastases from colorectal cancer were treated by continuous intraarterial chemotherapy of 5-FU and leucovorin. The regimen was that 500 mg/body of 5-FU with 30 mg/ body of leucovorin was administered continuously for 5 days followed by no medication for 16 days. The effect of this therapy was evaluated, and the relationship between this therapy and p53 overexpression was also studied. A complete response was obtained in 3 patients and a partial response in 3 patients; the overall response rate was 38%. The response rate was 56% in patients of more than 6 courses, 57% in patients with positive p53, and 20% in patients with negative p53. The three-year survival rate was 31%, and median survival was 18 months. Duodenal ulcer occurred in 2 patients due to extravascular dislocation of catheter. A high response rate and favorable prognosis were obtained by this therapy. Maintenance of catheter and a short administration period are current issues.

Rigix plate system for anterior fixation of thoracolumbar vertebrae

Only a few plate systems are available for anterior fixation of thoracolumbar vertebrae because of the difficulty in fastening a screw and a plate together. If the fixation is inadequate, the screws will become loose. The Rigix plate system consists of screws made of titanium alloy and a plate made of pure titanium. All screws used for internal fixation are screwed into the plate. This system permits the use of anchor screws, which facilitate exertion of force to compress the vertebral bodies together or to distract them from each other. In this study, Rigix plates were used in 24 patients (20 with burst fractures and 4 with metastatic tumors). In the 20 patients with fracture, internal fixation with a graft and a Rigix plate was performed after anterior decompression. In the four patients with malignant tumors, total spondylectomy was performed anteriorly and posteriorly, followed by implantation of a vertebral prosthesis, and then internal fixation with a Rigix plate combined posterior instrumentation with Diapson (Stryker Co., Tokyo, Japan) pedicular screws. Bone union was achieved in all patients. Neither breakage of instruments nor loosening of connections occurred in any case. In patients treated for bone metastases, the reconstructed spinal structure was able to be maintained for a long period. Of the screws used, five (5%) were not able to remain fixed as intended because they were inserted at inappropriate angles into the plate, but the fixation itself was excellent. Because of the low profile, ease of manipulation (mean instrumentation time was 25 min), and compatibility with magnetic resonance imaging, the Rigix plate is useful for anterior fixation of thoracolumbar vertebrae.

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.

[A case of retinochoroidal optic neuropathy]

The patient was a 59-year-old male with impaired left vision. Before he was referred to this hospital, he was diagnosed as having optic nerve injury due to the trauma of a severe bruise on his left eye caused by a traffic accident, and relative afferent pupillary defect (RAPD) was negative. On his first examination in this department, RAPD was negative and funduscopy of the left eye demonstrated hyperemia of the optic disc and mild opacification at the posterior pole. Fluorescein fundus angiography showed circular hyperfluorescence around the optic disc and transverse linear hyperfluorescence appearing above and below the macula. From these findings a diagnosis of choloidal rupture was made. The form of choloidal rupture suggested an early stage of evulsion of the optic nerve. The impairment of visual acuity seemed to be caused by choloidal circulatory disturbance. The patient was therefore, had traumatic retinocholoidal optic neuropathy complicated by the rupture of the choloidal around the optic disc, disturbance of the optic disc, and opacification of the retinochoroid.

Activation of protein kinase B (Akt/RAC-protein kinase) by cellular stress and its association with heat shock protein Hsp27

Protein kinase B (PKB, also named as Akt or RAC-protein kinase), that is activated by cellular stress such as heat shock and hyperosmotic treatment, was revealed to be activated by oxidative stress and by chemical stressors of CdCl2 and NaAsO2 by measuring the activity of the enzyme immunoprecipitated from the transfected COS-7 cells. Upon stress treatment, a 30-kDa phosphoprotein was co-immunoprecipitated with PKB from the cells metabolic labeled with [32P]orthophosphate. The phosphoprotein was identified as Hsp27, a small heat shock protein, by immunoblot analysis and co-immunoprecipitation. The association of Hsp27 was specific to PKB as the heat shock protein was not co-immunoprecipitated with other protein kinases such as protein kinase C and PKN. When the cells were treated with H2O2, PKB was activated gradually and the association of Hsp27 with PKB increased concurrently with the enhancement of PKB activity. In heat-shocked cells, activation of PKB and the association of Hsp27 were detected immediately after the treatment, and the association of the heat shock protein decreased while PKB kept stimulated activity when the cells were further incubated at 37 degrees C. These results suggest that Hsp27 is involved in the activation process of PKB in the signal transduction pathway of various forms of stress.

Anti-endothelial cell antibodies in the sera of patients with mixed connective tissue disease--the clinical significance

To determine the clinical significance of anti-endothelial cell antibodies in mixed connective tissue disease (MCTD), we measured the titers of antibodies to both untreated and cytokine-treated endothelial cells (EC) in the sera of the MCTD patients by means of an enzyme linked immunosorbent assay. The mean titer of antibodies to untreated EC (aEC) in the sera of the MCTD patients was significantly higher than that for the healthy subjects. The mean titer of antibody to EC treated with IFN gamma, IL1 (aIL1-EC) or TNF alpha (aTNF-EC) was significantly higher than that of aEC in the sera of the MCTD patients with proteinuria, and the mean titer of aTNF-EC was significantly higher than that of aEC in the sea of the MCTD patients with pulmonary fibrosis. Furthermore, the mean titers of aIL1-EC and aTNF-EC in the sera of the MCTD patients with pulmonary fibrosis were significantly higher than those of aIL1-EC and aTNF-EC in the sera of the MCTD patients without pulmonary fibrosis. These results suggest that antibodies to cytokine-treated EC may play a more important role in the manifestation of renal or pulmonary lesions in MCTD patients than aEC.

Unbalanced membrane phospholipid compositions affect transcriptional expression of certain regulatory genes in Escherichia coli

The amount of porin protein OmpF in the outer membrane of Escherichia coli was reduced to one-third by the pgsA3 mutation that diminishes the amount of phosphatidylglycerol and cardiolipin in the membrane, whereas a cls (cardiolipin synthase) null mutation had no effect. Osmoregulation of OmpF was functional in the pgsA3 mutant. As assessed by the beta-galactosidase activities of lacZ fusions, the ompF expression was not reduced at the transcriptional level but was reduced about threefold at the posttranscriptional level by pgsA3. This reduction was mostly restored by a micF null mutation, and the micF RNA that inhibits the ompF mRNA translation was present 1.3 to 1.4 times more in the pgsA3 mutant, as assayed by RNase protection and Northern blot analyses. Elevation of the level of micF RNA was not restricted to acidic-phospholipid deficiency: OmpF was hardly detected and micF RNA was present 2.7 to 2.8 times more in a pssA null mutant that lacked phosphatidylethanolamine. Other common phenotypes of pgsA3 and pssA null mutants, reduced rates of cell growth and phospholipid synthesis, were not the cause of micF activation. Salicylate, which activates micF expression and inhibits cell motility, did not repress the flagellar master operon. These results imply that an unbalanced phospholipid composition, rather than a decrease or increase in the amount of specific phospholipid species, induces a phospholipid-specific stress signal to which certain regulatory genes respond positively or negatively according to their intrinsic mechanisms.

Hematopoietic stem cell-based gene therapy for acquired immunodeficiency syndrome: efficient transduction and expression of RevM10 in myeloid cells in vivo and in vitro

Gene delivery via the hematopoietic stem cell (HSC) offers an attractive means to introduce antiviral genes into both T cells and macrophages for acquired immunodeficiency syndrome (AIDS) gene therapy. An amphotropic retroviral vector encoding a bicistronic gene coexpressing RevM10 and the murine CD8alpha' chain (lyt2) was developed to transduce HSC/progenitor cells. After transduction of CD34+ cells isolated from human umbilical cord blood, the lyt2 molecule detected by flow cytometry was used to monitor the level of gene transduction and expression and to enrich RevM10-expressing cells by cell sorting without drug selection. Using this quantitative method, high levels of gene transduction and expression (around 20%) were achieved by high-speed centrifugation of CD34+ cells with the retroviral supernatant (spinoculation). After reconstitution of human bone marrow implanted in SCID mice (SCID-hu bone) with the transduced HSC/progenitor cells, a significant number of donor-derived CD14+ bone marrow cells were found to express the RevM10/lyt2 gene. Finally, replication of a macrophage-tropic human immunodeficiency virus-type 1 (HIV-1) isolate was greatly inhibited in the lyt2+/CD14+ cells differentiated from transduced CD34+ cells after the enrichment of lyt2+ population. Thus, the RevM10 gene did not appear to inhibit the differentiation of HSC/progneitor cells into monocytes/macrophages. The level of retrovirus-mediated RevM10 expression in monocytes/macrophages derived from transduced HSCs is sufficient to suppress HIV-1 replication.

Comparison of free and reversed pedicled posterior interosseous cutaneous flaps

The posterior interosseous cutaneous flap is characterized by its thinness and the adjustable length of its vascular pedicle. This flap can be used both as a free and reversed vascular pedicled flap. We applied the free flap mostly for reconstruction of the digits, and the reversed vascular pedicled flap for soft-tissue defects of the proximal hand. Of 17 free flaps, 16 survived completely, and 1 developed partial necrosis. Eleven flaps were elevated as reversed vascular pedicled flaps, three of which were combined with the lateral arm flap to cover large defects. In these three combined flaps, the posterior radial collateral artery was anastomosed to an artery in the recipient site to enhance circulation; all three flaps survived completely. Operative time was 30 to 40 minutes shorter for the reversed vascular pedicled flaps. Two of the remaining eight reversed vascular pedicled flaps developed partial necrosis. The flap success rate was thus higher in the free flaps than in the reversed vascular pedicled flaps.

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.

High transdominant RevM10 protein levels are required to inhibit HIV-1 replication in cell lines and primary T cells: implication for gene therapy of AIDS

Expression of antiviral genes in CD4+ T cells has been proposed as a strategy for gene therapy of AIDS. Over the past years, we and others have developed retroviral vectors encoding the RevM10 protein, a dominant-negative mutant of the HIV-1 Rev trans-activator protein. We could demonstrate gene transfer and inhibition of HIV-1 replication in cultured T cell lines and primary T cells. However, little is known about the levels of the antiviral protein required to achieve a therapeutic effect, particularly in primary cells. In this report, we compare different vector designs with regard to expression of the antiviral gene to develop an optimal vector for clinical applications. Our results demonstrate that intracellular steady-state RevM10 protein levels expressed from the Moloney murine leukemia virus (MoMLV), myeloproliferative sarcoma virus (MPSV) or mouse embryonic stem cell virus (MESV) promoters located in the long terminal repeat (LTR) were uniformly higher than from internal promoters (eg CMV, PGK). Analysis of selected vectors in acutely and chronically HIV-infected cell lines suggested that threshold levels of RevM10 expression are required to achieve inhibition of HIV replication. LTR-driven RevM10 expression also yielded high steady-state protein levels in activated primary T cells resulting in inhibition of HIV replication, and there was no apparent difference between the MoMLV, MPSV and MESV-LTR vectors. However, RevM10 expression was down-regulated in resting primary cells and consequently anti-HIV efficacy was significantly reduced. Taken together, the data suggest that relatively high steady-state levels of RevM10 protein are required to achieve inhibition of HIV replication and that the MPSV- and MESV-derived retroviral vectors show no advantage over the MoMLV-based vectors for expression of anti-HIV genes in human T cells.

Fas/Apo-1 (CD95)-mediated and CD95-independent apoptosis of malignant plasma cells

CD95 (Fas/Apo-1) mediates apoptosis in cells of various types. Expression of CD95 and its function were investigated in myeloma cells and most plasma cell lines have been found to be CD95-positive. Anti-CD95 antibody induced apoptosis in these cell lines in a manner dependent on intensity of CD95 expression. Bel-2 expression levels in these cell lines were not correlated with sensitivity to CD95-induced apoptosis. Myeloma cells from approximately 70% of cases analyzed expressed CD95, suggesting a high frequency of CD95 expression of myeloma cells. The incidence of CD95 expression in samples from extramedullary lesions were higher than those of bone marrow myeloma cells. Anti-CD95 antibody did not induce apoptosis in some freshly isolated myeloma cells despite the expression of CD95 induced apoptosis in myeloma cell lines in a manner dependent on intensity of CD95 expression. In fresh samples, intensity of CD95 expression was not correlated with apoptosis evoked by anti-CD95 antibody. Interestingly, isolated myeloma cells with an high-level expression of CD95 showed spontaneous apoptosis during in vitro incubation. This was observed in samples from cases with high serum levels of lactate dehydrogenase (LDH), suggesting that the LDH was derived from cells undergoing spontaneous apoptosis in vivo. Taken together, CD95 is expressed in most myeloma cell lines and in many freshly isolated myeloma cells. However, some of the latter escape from CD95-dependent apoptosis despite the expression of CD95. Moreover, some myeloma cells from cases with aggressive disease may undergo apoptosis in a CD95-independent manner. In this review, the significance of CD95 and apoptosis of myeloma cells are discussed.

Isolation of the active form of RAC-protein kinase (PKB/Akt) from transfected COS-7 cells treated with heat shock stress and effects of phosphatidylinositol 3,4,5-trisphosphate and phosphatidylinositol 4,5-bisphosphate on its enzyme activity

RAC-protein kinase (PKB/Akt) has been shown to be activated by growth factor stimulation as a downstream target of phosphatidylinositol 3-kinase and also by heat shock through a pathway independent of phosphatidylinositol 3-kinase. RAC-protein kinase was purified by antibody affinity chromatography from COS-7 cells transfected with the epitope-tagged expression plasmid. The protein kinase activity of RAC-protein kinase purified from heat-treated cells was 9-fold higher than the enzyme isolated from untreated control cells. Phosphatidylinositol 3,4,5-trisphosphate did not enhance the activity of RAC-protein kinase purified from either heat-treated cells or control cells, whereas phosphatidylinositol 4,5-bisphosphate suppressed the enzyme isolated from heat-treated cells. These results indicate that RAC-protein kinase may interact with phosphoinositides, however, it could not be activated by simple association with the product of phosphatidylinositol 3-kinase reaction.

A new device for the treatment of coloproctostomic stricture after double stapling anastomoses

OBJECTIVE

A new device of staple cutter was developed to evaluate the clinical effect for the treatment of rectal stricture after the double stapling anastomosis.

SUMMARY BACKGROUND DATA

The double stapling technique has become an established reconstruction method for patients with low anterior resection. The major complication of anastomotic stricture associated with circular stapling has been reported to be harmful and distressing. Because underlying mechanisms of stricture are not well understood, no prophylactic means have been developed and this results in postoperative dilation still being the only treatment available. Although various dilation methods are used for the treatment of stricture, none is fully satisfactory.

METHODS

Low anterior resection was performed in 30 patients with rectal carcinoma using a double stapling technique. First, the incidence of the anastomotic stricture and the clinical factors that contribute to the stricture formation were studied. Second, the clinical effects and advantages of the treatment of coloproctostomic stricture using the newly developed device (staple cutter) were evaluated.

RESULTS

Nine (30%) of 30 patients had anastomotic stricture with the symptom of distressing frequent bowel movement. There was no significant relation between the clinical factors and the stricture when compared with that of nonstricture patients. Excellent dilation was performed in all of the nine strictures using the staple cutter, and the symptom of stricture disappeared dramatically in eight patients (89%) within 1 week. The recurrence of stricture occurred in two patients; however, it has not been observed after one further use of this treatment. The staple cutter is safe and easy to use even at the bedside, and except for a conventional anoscope, no special equipment, including fluoroscope, was needed.

CONCLUSIONS

From the significant effects and advantages, the procedure using staple cutter is recommended highly for the treatment of circular stapling anastomotic stricture of the rectum.

Repair of defects in spondylolysis by segmental pedicular screw hook fixation. A preliminary report

STUDY DESIGN

Clinical testing of segmental pedicular screw hook fixation repairing defects in lumbar spondylolysis.

OBJECTIVES

The authors tested segmental pedicular screw hook fixation using ISOLA implants (AcroMed Corp., Cleveland, OH) to maintain direct repair of the defect in pars interarticularis while fusion occurs. The device should not break while fusion takes place with out a postoperative body cast.

SUMMARY OF BACKGROUND DATA

Previous techniques of direct repair of defects in lumbar spondylolysis have not been successful universally, and wire breakage has occurred despite the use of a postoperative body cast.

METHODS

This technique stabilizes bone grafted to the detect by a pedicular screw, a hook, and a rod used in combination. Six patients with lumbar spondylolysis were treated by means of this technique.

RESULTS

Postoperatively, all patients with low back pain or radicular pain experienced significant relief. Radiographs, including lateral flexion-extension radiographs and tomograms, showed five patients to have a bilateral union and one a unilateral union, and none of the instrumentation failed.

CONCLUSION

This technique is considered useful for direct repair of the defects found in lumbar spondylolysis.

[The effect of intraportal chemotherapy in terms of administered dose of 5-FU]

Forty-six patients with colorectal cancer were studied for the effects of intraportal chemotherapy in terms of the administered dose of 5-FU. No liver metastases occurred in patients with a total dose of more than 4 g of 5-FU. The five-year survival rate for patients with a total dose of more than 4 g of 5-FU was 98%, which was better than that for control (72%). In patients administered 500 approximately 600 mg/body/day of 5-FU, the concentration of 5-FU in the peripheral blood was 0.022 approximately 0.027 microgram/ml. Liver dysfunction occurred in 22%, 33%, and 80% of patients administered less than 4 g, 4 approximately 4.9 g, or more than 5 g of 5-FU, respectively, but almost all of them were grade 1. These results suggest that intraportal chemotherapy administered with a total of more than 4 g of 5-FU was effective for prevention of liver metastases after resection of colorectal cancer.