The postoperative platelet-to-lymphocyte ratio predicts the outcome of patients undergoing pancreaticoduodenectomy for pancreatic head cancer

PURPOSE

The preoperative platelet-to-lymphocyte ratio (PLR) has been reported as an important prognostic index for pancreatic ductal adenocarcinoma (PDAC); however, the significance of the postoperative (post-op) PLR for this disease has not been elucidated.

METHODS

We analyzed data on 118 patients who underwent pancreaticoduodenectomy for pancreatic head PDAC, collected from a prospectively maintained database. The post-op PLR was obtained by dividing the platelet count after surgery by the lymphocyte count on post-op day (POD) 14. The patients were divided into two groups according to a post-op PLR of < 310 or ≥ 310. Survival data were analyzed.

RESULTS

A high post-op PLR was identified as a significant prognostic index on univariate analysis for disease-free survival (DFS) and overall survival (OS). The post-op PLR remained significant, along with tumor differentiation and adjuvant chemotherapy, on multivariate analysis for OS (hazard ratio = 2.077, 95% confidence interval: 1.220-3.537; p = 0.007). The post-op PLR was a significant independent prognostic index for poor DFS, along with tumor differentiation and lymphatic invasion, on multivariate analysis (hazard ratio = 1.678, 95% confidence interval: 1.056-2.667; p = 0.028).

CONCLUSIONS

The post-op PLR in patients with pancreatic head PDAC was an independent predictor of DFS and OS after elective resection.

Superior mesenteric vein/portal vein contact in preoperative imaging indicates biological malignancy in anatomically resectable pancreatic cancer

BACKGROUND

Pancreatic cancer in contact with the superior mesenteric vein/portal vein is classified as resectable pancreatic cancer; however, the biological malignancy and treatment strategy have not been clarified.

METHODS

Data from 186 patients who underwent pancreatectomy for pancreatic cancer were evaluated using a prospectively maintained database. The patients were classified as having resectable tumors without superior mesenteric vein/portal vein contact and with superior mesenteric vein/portal vein contact of ≤180°. Disease-free survival, overall survival, and prognostic factors were analyzed.

RESULTS

In the univariate analysis, superior mesenteric vein/portal vein contact in resectable pancreatic cancer was a significant prognostic index for disease-free survival and overall survival. In the multivariate analysis for poor disease-free survival, the superior mesenteric vein/portal vein contact remained significant (hazard ratio = 2.13, 95% confidence interval: 1.29-3.51; p < 0.01). In the multivariate analysis, superior mesenteric vein/portal vein contact was a significant independent prognostic index for overall survival (hazard ratio = 2.17, 95% confidence interval: 1.27-3.70; p < 0.01), along with sex, tumor differentiation, nodal involvement, and adjuvant chemotherapy. Portal vein resection for superior mesenteric vein/portal vein contact did not improve the overall survival (p = 0.86).

CONCLUSIONS

Superior mesenteric vein/portal vein contact in resectable pancreatic cancer was found to be an independent predictor of disease-free survival and overall survival after elective resection. Thus, pancreatic cancer in contact with the superior mesenteric vein/portal vein may be considered as borderline resectable pancreatic cancer.

The Impact of Fibrinogen to Prognostic Nutritional Index Rate on Prognosis of Pancreatic Ductal Adenocarcinoma

INTRODUCTION

The aim of the present study was to evaluate the prognostic value of the ratio of serum fibrinogen to prognostic nutritional index (PNI; Fbg/PNI) in patients undergoing resection for pancreatic ductal adenocarcinoma.

METHODS

A total of 140 patients who had undergone resection for pancreatic cancer were included. Patients were divided into two groups according to a Fbg/PNI ≥8.8 or <8.8. Survival data were analyzed using the log-rank test for univariate analysis and Cox proportional hazards for multivariate analysis.

RESULTS

Fbg/PNI was a significant prognostic indicator in univariate analysis for overall survival (OS) and disease-free survival (DFS). Fbg/PNI retained significance in multivariate analysis for OS (hazard ratio, 1.81; 95% confidence interval, 1.19-2.77; P < .01) in addition to tumor differentiation and nodal involvement. Fbg/PNI was a significant independent prognostic indicator of poor DFS on multivariate analysis (hazard ratio, 1.54; 95% confidence interval, 1.05-2.26; P = .03).

CONCLUSION

Preoperative Fbg/PNI is a novel significant independent prognostic indicator for OS and DFS following resection of pancreatic cancer with curative intent.

Double cone-unit laparoscopic hepatic resection for tumors adjacent to the hepatic vein

BACKGROUND

In tumor adjacent to the hepatic vein, it is important to treat two tertiary Glissonean pedicles that straddle to the hepatic vein in order to remove the tumor with a negative margin. The anatomical resection of the smallest unit may be considered to be the resection of the double cone-unit (DCU) in small tumor adjacent to the vein.

PATIENTS AND METHODS

127 patients who had undergone laparoscopic hepatectomy at the Jikei Medical University Hospital from 2020 through 2021. In 5 cases, Laparoscopic DCU resection was performed. If the CT image shows a hepatic vein near the tumor and the tumor is relatively small, less than 50 mm in size, DCU resection should be considered. After approaching the target Glissonean pedicles, the Bulldog Clamps were used to testing clamp it. After clamping it, the ICG was injected from peripheral veins. A few minutes later, the tumor-bearing portal territory could be identified as negative regions of fluorescence in the near infrared imaging system. The target hepatic vein, which runs between the two territories, was dissected where it transitions from the first to the second territory.

RESULTS

The median operative time in these 5 patients was 279 min, and the median volume of blood loss was 290 g. The average tumor size was 33 mm and the average surgical margin was 4.5 mm.

CONCLUSION

In small tumor adjacent to the hepatic vein, the anatomical hepatectomy of the smallest unit may be the Double Cone-Unit resection.

Thrombectomized autologous portal Y-graft inflow construction can be an option in living-donor liver transplantation: a case report

BACKGROUND

In living-donor liver transplantation (LDLT), portal Y-graft interposition using the recipient's portal vein (PV) bifurcation has been used for right lobe grafts with double PV orifices. We herein report the use of thrombectomized autologous portal Y-graft interposition for a recipient with preoperative portal vein thrombosis (PVT) in a right lobe LDLT with double PV orifices.

CASE PRESENTATION

The recipient was a 54-year-old male with end-stage liver disease due to alcoholic liver cirrhosis. There was PV thrombus in the recipient's PV. The living liver donor was his 53-year-old spouse, and a right lobe graft was planned for the transplantation. Since the donor's liver had a type III PV anomaly, autologous portal Y-graft interposition after thrombectomy was planned for PV reconstruction in the LDLT. The portal Y-graft was resected from the recipient and a thrombus extending from the main PV to the right PV branch was removed on the back table. The portal Y-graft was anastomosed to the anterior and posterior portal branches of the right lobe graft. Followed by venous reconstruction, the Y-graft was anastomosed to the recipient's main PV. The operation time was 545 min and the intraoperative blood loss was 1355 ml. The recipient was discharged on postoperative day 13 without any complications. The recipient remains well with the patency of the portal Y-graft one year after the liver transplantation.

CONCLUSION

We herein report the successful use of autologous portal Y-graft interposition after thrombectomy on the back table for a recipient with PVT in a right lobe LDLT.

Impact of C-reactive protein-albumin-lymphocyte (CALLY) index on prognosis after hepatectomy for colorectal liver metastasis

AIM

The C-reactive protein (CRP)-albumin-lymphocyte (CALLY) index is a novel inflammation-based biomarker. We aimed to investigate whether the CALLY can predict the prognosis in patients with colorectal liver metastases (CRLM) after hepatic resection.

METHODS

We included 183 patients with CRLM who underwent hepatectomy. The CALLY index was defined as (albumin × lymphocytes)/(CRP × 10⁴). We investigated the association of the CALLY index with overall survival by univariate and multivariate analyses.

RESULTS

In total, 101 (55%) patients had a low CALLY index (<4). In the univariate analysis, overall survival was significantly worse in patients with lymph node metastases (p = 0.02), extrahepatic lesions (p < 0.01), and a low CALLY index (p < 0.01). In the multivariate analysis, independent and significant predictors of overall survival were lymph node metastases (p = 0.04), extrahepatic lesions (p = 0.03), and a low CALLY index (p = 0.03). Patients with a low CALLY index had significantly more postoperative complications than those with a high CALLY index (29% vs. 11%, p < 0.01).

CONCLUSION

The CALLY index may be an independent and significant indicator of outcomes in patients who underwent liver resection for CRLM.

Significant impact of cachexia index on the outcomes after hepatic resection for colorectal liver metastases

Introduction

The purpose of this study was to investigate the relation between preoperative cachexia index (CXI) and long‐term outcomes in patients with colorectal liver metastases (CRLM) after hepatic resection.

Method

In all,118 patients who underwent hepatic resection for CRLM were analyzed retrospectively. The relationship between CXI and the long‐term outcomes in patients after hepatic resection was investigated. CXI was calculated based on preoperative skeletal muscle index, serum albumin level, and neutrophil–lymphocyte ratio.

Results

The multivariate analysis showed that extrahepatic lesion (hazard ratio [HR] 2.86, 95% confidence interval [CI] 1.48–5.53, P < .01) and high CXI (HR 0.44, 95% CI 0.20–0.98, P = .04) were independent and significant predictors of disease‐free survival. Moreover, extrahepatic lesion (HR 2.32, 95% CI 1.03–5.22, P = .04), high CXI (HR 0.17, 95% CI 0.05–0.57, P < .01), and curability R 1 or 2 (HR 3.29, 95% CI 1.23–8.78, P = .02) were independent and significant predictors of overall survival.

Conclusion

CXI is a useful prognostic factor for disease‐free survival and overall survival after hepatic resection in CRLM patients.

Living donor liver transplantation for idiopathic portal hypertension with focal nodular hyperplasia

The patient was a 61-year-old woman with a history of diabetes mellitus who had undergone ileocecal resection for ascending colon carcinoma 5 years earlier, followed by a postoperative adjuvant chemotherapy with XELOX (capecitabine + oxaliplatin). During follow-up, the liver gradually atrophied, and radiological imaging showed suspicious findings of 20 × 14 mm hepatocellular carcinoma (HCC) in the right lobe of the liver. The patient also underwent endoscopic variceal ligation for the esophageal varices. She was referred to our hospital for living donor liver transplantation (LDLT) due to decompensated liver cirrhosis with HCC. The patient did not have hepatitis B or C, and history of alcohol, suggesting that her liver cirrhosis was caused by a non-alcoholic steatohepatitis. The Child-Pugh score was 10 points (class C) and the Model for End-Stage Liver Disease (MELD) score was 8 points. The possibility of HCC could not be ruled out, and LDLT was performed. Postoperative pathological examination revealed idiopathic portal hypertension (IPH), and the mass lesion was diagnosed as focal nodular hyperplasia (FNH). The postoperative course was uneventful and the patient was discharged on postoperative day 14. This is the first case of liver transplantation for IPH with FNH.

Pancreatic intraepithelial neoplasia with carcinoma in situ with repeated distally localized pancreatitis: a case report

Background

Acute pancreatitis could be an early symptom of pancreatic cancer. However, repeated pancreatitis caused by pancreatic cancer is very rare.

Case presentation

A 69-year-old man was referred to our hospital with severe abdominal pain, and serial imaging studies showed acute distally localized pancreatitis with a pseudocyst. Although he had successful conservative medical treatment followed by discharge from the hospital, he was re-admitted with severe abdominal pain for recurrent distal pancreatitis with splenic artery aneurysm followed by its rupture. No pancreas mass was detected by imaging studies including endoscopic ultrasound and cytologic studies of the pancreas juice did not show any malignant cells, although slight dilatation of distal pancreas duct was observed only in the initial computed tomography. Because of the episodes of repeated distally localized pancreatitis caused by possible pancreatic ductal neoplasm, we planned and performed laparoscopy-assisted distal pancreatectomy after full-informed consent. Pathological examination revealed pancreatic intraepithelial neoplasia (PanIN) with carcinoma in situ in the distal main pancreas duct. The post-surgical course of the patient was uneventful and he was discharged 10 days after surgery from recurrent disease for over a year.

Conclusions

We encountered a case of repeated episodes of acute distally localized pancreatitis, for which distal pancreatectomy was performed, resulting in pathological diagnosis of PanIN with carcinoma in situ.

Novel combined fibrosis-based index predicts the long-term outcomes of hepatocellular carcinoma after hepatic resection

AIM

Liver fibrosis influences liver regeneration and surgical outcomes. The fibrosis-4 (FIB-4) index is strongly associated with liver fibrosis and cirrhosis. This study aimed to examine the prognostic significance of the combination of FIB-4 index and Protein Induced by Vitamin K Absence or Antagonist-II (PIVKA-II) (PIVKA-II-FIB-4 index score) in patients who underwent curative resection for hepatocellular carcinoma (HCC).

METHODS

We included 284 patients who underwent elective hepatic resection for HCC between January 2000 and December 2018. We retrospectively investigated how FIB-4 index is related to disease-free survival and overall survival.

RESULTS

According to a receiver operating characteristic (ROC) analysis, the optimal cutoff value of the FIB-4 index was 3.44. In a multivariate analysis, high PIVKA-II and FIB-4 index values were independent predictors of both disease-free survival (P = 0.013 and P = 0.005, respectively) and overall survival (P = 0.048 and P < 0.001, respectively). We classified the PIVKA-II and FIB-4 index levels into two groups (high vs. low) and calculated a new score (PIVKA-II-FIB-4 index score; 0-2) by the sum of each measurement (high, 1; low, 0). The 5 year overall survival rates of patients with PIVKA-II-FIB-4 index scores of 0, 1, and 2 were 84.9, 74.4, and 47.1%, respectively (P < 0.001).

CONCLUSION

The combination of the preoperative PIVKA-II and FIB-4 index may be a prognostic factor of HCC after hepatic resection, suggesting that the combined score is useful in assessing the liver fibrosis status in cancer cases.

Safer Vitrification of Mouse and Human Embryos Using the Novel Cryoroom Vitrification System for Assisted Reproductive Technology

BACKGROUND

Vitrification is widely used for assisted reproductive technology (ART). Most vitrification devices require the skillful placement of embryos into the carrier and aspiration of excessive vitrification solution.

OBJECTIVE

To evaluate the efficacy and safety of the Cryoroom as a vitrification device.

MATERIALS AND METHODS

Mouse and human embryos were vitrified with Cryoroom or Cryotop, and the developmental potency was assessed in vitro. Mouse monozygotic twin blastocysts were vitrified with Cryoroom or Cryotop for microarray analysis.

RESULTS AND DISCUSSION

In mouse and human embryos, there were no differences between the survival and developmental progress in each device. In silico, the Cryoroom device showed no changes, particularly in DNA methylation after vitrification compared with the Cryotop. These results showed that the form and function of the device may affect the gene expression levels in vitrified embryos.

CONCLUSION

The Cryoroom represents a safe and potentially revolutionary vitrification device for ART.

Iron dependent degradation of an isothiazolone biocide (5-chloro-2-methyl-4-isothiazolin-3-one)

An isothiazolone biocide, 5-chloro-2-methyl-4-isothiazolin-3-one (CMI), was degraded in the presence of iron. According to the Fe-dependent degradation of CMI, stoichiometric production of chloride was observed. Copper and stainless steel did not enhance the physico-chemical degradation of CMI, whilst phosphate inhibited the Fe-dependent degradation. Neither aerobic nor anaerobic conditions influenced the Fe-dependent CMI degradation. Furthermore, FeO(OH)-powder and Fe(3)O(4)-powder did not lead to the physico-chemical degradation of CMI. Rapid disappearance of CMI was observed in an operating cooling water plant. CMI added to the cooling tower declined from 1.4 mg l(-1) to < 0.1 mg l(-1) in 2 d. This finding is important in optimising the use of CMI and combating resistance if encountered.

The survival response of Escherichia coli K12 in a natural environment

To verify the hypothesis of cryptic growth and viable but nonculturable (VBNC) state, survival responses of Escherichia coli cells were examined under oligotrophic microcosm conditions for an extended period. In the case of filtered distilled water at 4 degrees C, E. coli cells definitely entered the VBNC state within 56 days. However, culturability and viability increased while the total number of cells declined after 110 days. This phenomenon can be explained by considering three possible states. The first is the existence of the VBNC state, the second is cryptic growth, and the third is the death of E. coli cells. In the case of artificial seawater at 4 degrees C, VBNC E. coli cells confirmed the existence of two log units of elongated VBNC cells. Moreover, elongated VBNC cells showed the most significant change among all the other transformed cells. Also, E. coli cells in microcosms at 28 degrees C indicated the entrance to the classical starvation survival state. In resuscitation tests, 1% diluted Luria-Bertani agar medium showed the highest level of resuscitation among amended agar media. To evaluate the survival ability of E. coli cells in the activated sludge samples, we used an E. colistrain XL-1 blue containing plasmids pQ2 including GFPcDNA (XL/GFP). In supernatant of activated sludge (SUP) at 28 degrees C, XL/GFP cells entered the VBNC state after 10 days, whereas existence of VBNC cells was not detectable in resuspended activated sludge (ACT) at 28 degrees C.

Antibacterial activity of Bacillus amyloliquefaciens phage endolysin without holin conjugation

To characterize the enzymatic activity and antibacterial activity of endolysin encoded by a Bacillus amyloliquefaciens phage, the open reading frame encoding endolysin was amplified by PCR and cloned into the expression plasmid pET21d(+). The resultant plasmid was used to transform Escherichia coli JM109(DE3). Production of endolysin in the cytosol facilitated cell lysis without coproduction of holin, which is considered to degrade or alter the cytoplasmic membrane. The phage endolysin was overexpressed and purified. Although the specific activity of the purified phage endolysin towards lyophilized Micrococcus luteus cells was 1/11 of the activity of chicken egg white lysozymes, the endolysin showed stronger antibacterial activity towards E. coli W3110, E. coli JM109(DE3) and Pseudomonas aeruginosa PAO1 than chicken egg white lysozymes. The antibacterial activity of the endolysin towards these three bacterial strains was marked when EDTA was added to the endolysin solution.

Characterization of oxygen-dependent lysis of Escherichia coli cells infected by bacteriophage T4

Infection of Escherichia coli cells by T4 phage at a multiplicity of infection (MOI) of 0.01 caused inhibition of cell lysis for up to 4 h. Such cells grown under aerobic condition were lysed by external stimuli such as cold shock, osmotic shock or addition of toxic substances, e.g., carbonyl cyanide m-chlorophenylhydrazone (CCCP). However, the effects of these external stimuli were reduced by transferring the cells to static incubation, by which dissolved oxygen was consumed by the cells within 10 min. The cells became insensitive to such external stimuli when the culture was deoxygenated with nitrogen gas. Following infection with a lysozyme amber mutant, eL1a, the cell membrane permeability was found to be increased either by cold shock or osmotic shock treatment of cells grown under aerobic conditions, but not in cells transferred to the static incubation. Oxygen limitation was suggested to enhance membrane stability in relation to cell lysis following the cold or osmotic shock treatment.

Bacillus amyloliquefaciens phage endolysin can enhance permeability of Pseudomonas aeruginosa outer membrane and induce cell lysis

To determine the function of the C-terminal region of Bacillus amyloliquefaciens phage endolysin on Pseudomonas aeruginosa lysis, the permeabilization of the outer membrane of P. aeruginosa was analyzed. Glu-15 to His (E15H) and Thr-32 to Glu (T32E) substitutions were introduced into the Bacillus phage endolysin. Neither E15H nor T32E substitution induced enzymatic and antibacterial activities. These two, Glu-15 and Thr-32, were considered to be the active center of the enzyme. The addition of purified E15H and T32E proteins to P. aeruginosa cells induced the release of periplasmic beta-lactamase from the cells, indicating that both proteins enhance permeabilization of the outer membrane. However, the addition of E15H and T32E proteins to P. aeruginosa cells did not induce the release of cytoplasmic ATP from the cells. These results indicate that the antibacterial activity of the endolysin requires both the C-terminal enhancement of the permeabilization of the P. aeruginosa outer membrane and N-terminal enzymatic activity.

Association of genetic polymorphisms in CYP19 and CYP1A1 with the oestrogen receptor-positive breast cancer risk

Since tamoxifen has been shown to reduce the risk of oestrogen receptor (ER)-positive, but not ER-negative, breast cancers in a chemoprevention trial (P-1), it is important to develop assays to assess risk factors for ER-positive breast cancer in order to appropriately select candidates for chemoprevention with tamoxifen. Thus, the significance of genetic polymorphisms of genes involved in oestrogen biosynthesis (CYP19) and metabolism (CYP1A1) as a risk factor for ER-positive breast cancers was evaluated. A case-control study was conducted with 257 breast cancer patients and 191 healthy female controls. Two polymorphisms, CYP19 (TTTA repeats) in intron 4 and CYP1A1 6235C/T in the 3' non-coding region, and their association with the breast cancer risk after adjustment for the other epidemiological risk factors were examined. CYP19 (TTTA)7(-3bp) allele carriers showed a significantly (P<0.05) increased risk of ER-positive breast cancers (Odds Ratio (OR)=1.72, 95% Confidence Interval (CI) 1.10-2.69), but not ER-negative breast cancers. CYP1A1 6235C allele carriers showed a non-significant (P=0.06) trend towards a decreased risk of ER-positive breast cancers (OR=0.65, 95% CI 0.42-1.02), but not ER-negative breast cancers. The combination of these two polymorphisms was found to be more useful in the assessment of the ER-positive breast cancer risk (OR=3.00, 95% CI=1.56-5.74) than the CYP19 (TTTA)7(-3bp) polymorphism alone. The combination of CYP19 (TTTA)7(-3bp) and CYP1A1 6235C/T polymorphisms is associated with an ER-positive, but not ER-negative, breast cancer risk, and, thus, would be useful in the selection of candidates for chemoprevention with tamoxifen.

Toward rational control of Escherichia coli O157:H7 by a phage cocktail

Twenty six phages infected with Escherichia coli O157:H7 were screened from various sources. Among them, nine caused visible lysis of E. coli O157:H7 cells in LB liquid medium. However, prolonged incubation of E. coli cells and phage allowed the emergence of phage-resistant cells. The susceptibility of the phage-resistant cells to the nine phages was diverse. A rational procedure for selecting an effective cocktail of phage for controlling bacteria was investigated based on the mechanism of phage-resistant cell conversion. Deletion of OmpC from the E. coli cells facilitated the emergence of cells resistant to SP21 phage. After 8 h of incubation, SP21-resistant cells appeared. By contrast, alteration of the lipopolysaccharide (LPS) profile facilitated cell resistance to SP22 phage, which was observed following a 6-h incubation. When a cocktail of phages SP21 and SP22 was used to infect E. coli O157:H7 cells, 30 h was required for the emergence of cells (R-C) resistant to both phages. The R-C cells carried almost the same outer membrane and LPS components as the wild-type cells. However, the reduced binding ability of both phages to R-C cells suggested disturbance of phage adsorption to the R-C surface. Even though R-C cells resistant to both phages appeared, this work shows that rational selection of phages has the potential to at least delay the emergence of phage resistance.

Successful treatment of refractory T-cell acute lymphoblastic leukemia by unmanipulated stem cell transplantation from an HLA 3-loci mismatched (haploidentical) sibling

We describe a patient with refractory T-cell acute lymphoblastic leukemia who successfully underwent unmanipulated stem cell transplantation from an HLA 3-loci mismatched (haploidentical) sibling. In order to avoid severe graft-versus-host disease (GVHD), we used intensified GVHD prophylaxis consisting of tacrolimus, a short course of methotrexate, methylprednisolone, and mycophenolate mofetil. Hematopoietic reconstitution was rapid, with neutrophil count >5 x 10(8)/l on day +16, and platelet count >2 x 10(10)/l on day +25. There was no evidence of clinical acute GVHD. Bacterial, fungal, and viral infections were well controlled with antibiotics. The patient is still in complete remission past day +400. We suggest that unmanipulated HLA-mismatched transplantation with intensified GVHD prophylaxis is an alternative option for patients who do not have an HLA-identical donor.

Effect of dispersing oil phase on the biodegradability of a solid alkane dissolved in non-biodegradable oil

Acinetobacter sp. CR was grown on a model oil, which consisted of an inert oil matrix of pristane with n-heneicosane dissolved in it as the sole carbon source, in a stirred-tank bioreactor. This bacterium takes up substrates from the oil phase by direct contact with the oil phase. A previously established mathematical model was applied to reveal the effect of agitation conditions on the growth and n-alkane degradation kinetics of the bacterium. Higher impeller speed resulted in both lower microbial growth and lower n-alkane degradation rate of the bacterium, although it increased the specific surface area of the oil, which was measured by a previously developed device. This result was due to the decreased number of cells adhering to the oil surface, i.e., intense agitation inhibited the adhesion of cells to the oil surface. The addition of a surfactant below a critical micelle concentration (CMC) inhibited the degradation of n-heneicosane dissolved in pristane, although the biodegradability of the substrate recovered gradually with the increase in the dose of surfactant over CMC. The results suggest that efforts to increase the specific surface area of the oil phase have the undesirable result of inhibiting oil degradation when the dominant microbial degraders take up substrates in oil by direct contact with the oil.

Construction of self-disruptive Bacillus megaterium in response to substrate exhaustion for polyhydroxybutyrate production

In order to establish a novel recovery system for polyhydroxyalkanoates, a self-disruptive strain of Bacillus megaterium that responds to substrate exhaustion was constructed. A gene cassette carrying the lysis system of Bacillus amyloliquefaciens phage - holin and endolysin - was inserted into the Escherichia coli- Bacillus subtilis shuttle vector pX under the control of a xylose-inducible expression system, xylR-xylA '. In this system, the expression of a target gene is induced by xylose but inhibited by glucose, which acts as an anti-inducer. B. megaterium was transformed with pX conveying the phage lysis system, which was integrated into the amyE locus of chromosomal DNA of B. megaterium by homologous recombination. The lysis system caused self-disruption of the transformant cells effectively even when expression of the lysis genes was induced during stationary phase. For the production of polyhydroxybutyrate (PHB), the transformant was grown in a medium containing glucose as a substrate in the presence of xylose. When the glucose concentration approached zero, self-disruption was spontaneously induced, releasing intracellularly accumulated PHB into the culture broth. This system realizes timely cell disruption immediately after the PHB content in the cell reaches a maximum level.

Fungal contribution to in situ biodegradation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) film in soil

The contribution of fungi to the microbial degradation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) films in soil was studied. Various traces, cavities, and grooves observed on the dented surface of PHBV films demonstrated that the degradation was a concerted effect of a microbial consortium colonizing the film surface, including fungi, bacteria, and actinomycetes. The succession of microbial consortia in the soil around the PHBV films during the degradation showed a distinctive increase in the fungal population, resulting in its dominance. Comparison of the degradation ability of microbial strains isolated from soil where PHBV films were degraded, revealed that fungi showed the highest contribution to PHBV degradation, growing very rapidly along the film surface with their high degradation ability and then expanding their hyphae in a three-dimensional manner.

Fate of coliphage in waste water treatment process and detection of phages carrying the Shiga toxin type 2 gene

Abundances of phages specific to Escherichia coli in the wastewater treatment process were analyzed. Relatively abundant coliphages were detected in sewage influent. Phages in the influent were found both suspended in liquid phase and attached on the solid particles. Phage concentration was not reduced in the settling tank without chemical agglutination. Anaerobic followed by aerobic treatment of the sewage reduced concentration of suspended phages. Almost no phage was detected as a suspended form in the aerobic tank. Most of the phages were detected as attaching form and were excluded by aggregation with sludge. Using an experimental approach based on the detection of Shiga toxin 2 (Stx 2) gene by a phage enrichment culture followed by nested PCR, bacteriophages carrying Stx 2 gene were detected in the influent, settling tank, and anaerobic tank. It was revealed that the presence of phages carrying Stx 2 gene is common in sewage and these phages are effectively eliminated through sewage treatment process.

Pancreatic mass due to chronic pancreatitis: correlation of CT and MR imaging features with pathologic findings

OBJECTIVE

The purpose of this study was to identify helical CT and MR imaging features of pancreatic masses (focal enlargement) due to chronic pancreatitis and their correlation with pathologic findings.

CONCLUSION

When histologic fibrosis is uniformly present through the pancreas in patients with chronic pancreatitis, there is no demarcation of masses due to chronic pancreatitis. When there is a greater degree of histologic fibrosis in the masslike part of the pancreas, the mass is often demarcated from the remaining pancreas, and the enhancement pattern on two-phase helical CT and dynamic gadolinium-enhanced MR imaging mimics that of pancreatic adenocarcinoma.

Functional analysis of antibacterial activity of Bacillus amyloliquefaciens phage endolysin against Gram-negative bacteria

To analyze the antibacterial activity of Bacillus amyloliquefaciens phage endolysin, nine deletion derivatives of the endolysin were constructed. Each deletion mutant was overexpressed, purified and characterized. The catalytic domain was located on the N-terminal region and the C-terminus had an affinity with the bacterial envelope. The enzymatic activity remained in spite of the deletion of the C-terminal 116-amino acid region; however, the antibacterial activity was lost. These results indicate that antibacterial action requires both the C-terminal cell-binding and the N-terminal enzymatic activities.

Programmed Escherichia coli cell lysis by expression of cloned T4 phage lysis genes

Self-disruptive Escherichia coli that produces foreign target protein was developed. E. coli was co-transformed with two vector plasmids, a target gene expression vector and a lysis gene expression vector. The lytic protein was produced after the expression of the target gene, resulting in simplification of the cell disruption process. In this study, the expression of cloned T4 phage gene e or t was used for the disruption of E. coli that produced beta-glucuronidase (GUS) as a model target protein. The expression of gene e did not lead to prompt cell disruption but weakened the cell wall. Resuspension with deionized water facilitated cell lysis, and GUS activity was observed in the resuspended liquid. Expression of gene e at mid logarithmic growth phase was the optimal induction period for GUS production and release. On the other hand, the expression of gene t induced immediate cell lysis, and intracellular GUS was released to the culture medium. Maximum GUS production was obtained when gene t was induced at late logarithmic growth phase.

Laparoscopic adrenalectomy: lateral transabdominal approach vs posterior retroperitoneal approach

Laparoscopic adrenalectomy has been used to remove a wide variety of adrenal neoplasms. Although several laparoscopic approaches to the adrenal gland have been described, the lateral transabdominal approach has several advantages when compared with other approaches for laparoscopic adrenalectomy. From October 1995 to July 1999, we performed laparoscopic adrenalectomies on 16 patients, including eight posterior retroperitoneal approaches and eight lateral transabdominal approaches. Sixteen patients, ranging in age from 23 to 69 years, were treated for the following conditions: non-functioning adenoma, four patients; aldosteronoma, seven patients; pheochromocytoma, three patients; Cushing's adenoma, two patients. The average tumor size was 2.5 +/- 0.5 cm (1.8-3.0 cm, median 2.4 cm) in the lateral transabdominal approach, 1.2 +/- 0.8 cm (0.8-3.2 cm, median 1.75 cm) in the posterior retroperitoneal approach. Average operative time of lateral transabdominal approach was significantly shorter than that of the posterior retroperitoneal approaches (mean 129 min vs 269 min, P = 0.0005). Conversion to laparotomy was required in one patient in the posterior approach. Postoperative complication occurred in one pneumothorax in the lateral transabdominal approach and two subcutaneous emphysemas in the posterior retroperitoneal approach. There was no statistical difference in blood loss during the operation in the two groups. There was no mortality in either group. The lateral transabdominal approach is a safe and efficient technique for the removal of the adrenal neoplasms. Compared with other approaches, this technique has a wider working space and also good exposure for removing the adrenal gland.

Aggregate formation of rCHO cells and its maintenance in repeated batch culture in the absence of cell adhesion materials

Aggregate formation of recombinant Chinese hamster ovary (rCHO) cells capable of producing granulocyte colony-stimulating factor (G-CSF), using medium lacking cell adhesion materials in a repeated batch culture, was examined together with cell growth, cell viability and G-CSF production. The rCHO culture was conducted in a rotary shaker and the medium was changed every five days. The formation of stable cell aggregates with high reproducibility was observed after the first medium change. The size of the cell aggregates (consisting of several 10s to 40,000 cells) formed during the repeated batch culture ranged from 30 to 600 microm. The cell density of the aggregates reached as high as 2 x 10(6) cells/ml and the viability was maintained at more than 80% for 19 d. Changing the medium to avoid glucose exhaustion effectively maintained the cell density, cell viability and G-CSF productivity at high levels.

Stimulating accumulation of nitrifying bacteria in porous carrier by addition of inorganic carbon in a continuous-flow fluidized bed wastewater treatment reactor

Porous polyurethane carrier particles have been successfully applied for microbial immobilization to simultaneously remove carbonaceous and nitrogenous substances from wastewater by a fill-and-draw operation. This reactor system was extended to a continuous-flow operation mode, by which inorganic carbon (IC) was supplemented in order to stimulate the growth of autotrophic nitrifying bacteria. By addition of sodium bicarbonate, the ammonia oxidation reaction proceeded remarkably in the porous particle fluidized bed reactor, while a small increase in the nitrification was observed in a reactor with suspended microbes. Dissolved oxygen profile was obtained using an oxygen microelectrode to measure the microbial consumption of oxygen in the porous carrier. The size of ammonia-oxidizing bacterial populations in the carrier was proportional to the volume of the aerobic region of the carrier. The aerobic region decreased with the increase in sodium bicarbonate concentration, which improved the ammonia-oxidizing activity of retained nitrifiers in the carrier. The maximum ammonia oxidation rate was up to 55.6 gN/m3/h within the aerobic region of the carrier under the following feed conditions: 100 mg/l of total organic compound, 55 mg/l of ammonium concentration and 48 mg/l of inorganic carbon.

Sjögren's syndrome complicated with autoimmune hepatitis and antiphospholipid antibody syndrome

A 56-year-old Japanese female simultaneously developed thrombocytopenia, sicca symptoms, and an elevation of transaminase. Antiphospholipid antibodies were detected in her serum. The presence of anti-SS-A antibodies in the serum and sialectasis, disclosed by sialography, suggested the presence of primary Sjogren's syndrome (SjS). The laboratory data and the biopsy of the liver showed compatible findings with autoimmune hepatitis (AIH). Thrombocytopenia and liver dysfunction satisfactorily responded to corticosteroid. To our knowledge, this is the first reported case of SjS with AIH and antiphospholipid antibody syndrome (APAS). Analysis of serum cytokine levels showed a predominance of Th0-Th1 response, which is not compatible with AIH, in this complicated autoimmune state.

Evidence for a novel Chlorella virus-encoded alginate lyase

To clone the genes encoding lysis protein from a Chlorella virus, water samples were collected from 13 aquatic environments located in the Kanto area of Japan. Eight water samples contained plaque-forming viruses on Chlorella sp. NC64A, but no virus was detected in the other five samples. A novel Chlorella virus, CVN1, was isolated from the Inba-numa marsh sample. CVN1 genomic DNA was partially digested and shotgun cloned into pUC118 to identify the genomic region responsible for the lytic phenotype on Chlorella sp. NC64A. A DNA fragment which encoded two ORFs, ORF1 and ORF2, was obtained by antialgal assay. The ORF2 gene product, CL2, consisted of 333 amino acids showing antialgal activity not only on the original host of Chlorella sp. NC64A, but also on the heterogeneous hosts of Chlorella vulgaris C-27 and C. vulgaris C-207. CL2 showed a weak homology (19.8% amino acid identity) to mannuronate lyase SP2 from Turbo cornutus. CL2 in Escherichia coli cells was purified using a nickel chelate column. Lyase activity of purified CL2 on alginic acid was observed in an enzyme assay. The specific activity of purified CL2 was 2.1x10(-2) U mg(-1), the optimum pH for enzymatic activity was 10.5, and Ca(2+) was required for enzyme activity. This is the first report of a Chlorella virus protein with lyase activity.

Ovarian carcinoma with fistula formation to the sigmoid colon and ileum: report of a case

We describe herein an extremely rare case of clear cell type ovarian carcinoma resulting in fistula formation into the colon and intestine. The patient was a 61-year-old woman in whom a large tumor with extravasation from the sigmoid colon was found by barium enema examination. The tumor was preoperatively diagnosed as left ovarian cancer by angiography which showed the tumor feeder arising from the left ovarian and uterine arteries.

Structural analysis of a biofilm which enhances carbon steel corrosion in nutritionally poor aquatic environments

Carbon steel coupons were exposed to nutritionally-poor synthetic wastewater inoculated with activated sludge from a municipal waste water plant. Biofilm formation was observed after one day incubation, and the thickness of the film increased proportionally with the incubation period. Mass loss of the coupons was also proportional to the incubation time, and reached 70.4 (mg/cm2) after incubation for 140 d. The observed mass loss was 5 times as much as that under sterile conditions. To characterize the microbiologically influenced corrosion (MIC) of carbon steel, structural analysis of the biofilm was performed. Rapid decrease in the dissolved oxygen (DO) concentration in the zone near the surface of the biofilm was observed by a microelectrode mounted on a micromanipulator. Heterogeneous distribution of the DO concentration on the surface of the steel plate was observed after multiple analyses. The heterogeneous structure of the biofilm composed of viable cells, inanimate objects, voids and pores was elucidated by confocal scanning laser microscopy. Concentrations of both aerobic bacteria and sulphur-reducing bacteria in the biofilm decreased with the incubation time, indicating that the increase in the biofilm thickness reflected an increase in the density of dead microbial cells or in extracellular polymer accumulation by the microbes. The average roughness of the metal surface observed after 112 d of incubation was +/-7.14 microm, which was 14.1% of the average thickness of the coupons. These observations indicated that uneven distribution of the DO profile and the cell concentration were critical for MIC of the carbon steel.

Cloning and expression of a gene encoding the lytic functions of Bacillus amyloliquefaciens phage: Evidence of an auxiliary lysis system

A bacteriophage specific to Bacillus amyloliquefaciens, a gram-positive bacterium, was isolated from a local sewage treatment center. Using a lysis assay, a gene, lys1521, was isolated and its nucleotide sequence revealed one open reading frame of 375 bp. Homology studies showed amino acid alignment similarity with gene 5A of Bacillus subtilis phages PZA and phi29. Overexpression of the cloned gene yielded a 13 kDa protein corresponding to the predicted gene product. Despite the fact that no significant homology with known cell wall lytic enzymes was apparent, the lytic profile obtained in an in vivo expression assay showed that lys1521 had cell wall hydrolysis activity. This is a significant revelation since the function of the homologous gene 5A product of phage phi29 has been suggested to be required for the in vivo elongation of phage DNA replication. The lys1521 gene could be evidence of the presence in gram-positive bacteriophages of a third lysis gene in addition to the well characterized two-step lysis system.

Enhanced microbial adaptation to p-Nitrophenol using activated sludge retained in porous carrier particles and simultaneous removal of nitrite released from degradation of p-Nitrophenol

In order to examine the microbial degradation of p-nitrophenol (PNP) by a mixed culture system and simultaneous removal of nitrite released via the degradation, an activated sludge retained in porous carrier particles and a suspension culture as a control were acclimated to artificial sewage containing PNP as the sole carbon source. The adaptation of microbes retained in porous carrier particles to PNP was faster than that of suspended microbes by more than 20 d. After microbial adaptation to PNP, it was degraded completely without significant accumulation of intermediate metabolites. The PNP degradation activity of the retained microbes was more than 2 times higher than that of the suspended microbes. By increasing the retained microbial concentration, nitrite released from the degraded PNP was removed by denitrification. This research demonstrates that using microbes retained in porous carrier particles is not only effective for reduction of acclimation time but also enables simultaneous removal of the nitrogen compounds resulting from the degradation of nitroaromatics.

Antitumor effect of medium-chain triglyceride and its influence on the self-defense system of the body

Medium-chain triglyceride (MCT), long-chain triglyceride (LCT), and their mixture were compared in reference to both cytotoxic effect against human tumor cells and influence on the immune system. MCT showed more potent cytotoxicity than LCT. Continuous contact with MCT also inhibited the cytotoxic effect of lymphokine-activated killer (LAK) cells much more strongly than LCT. However, there is a discrepancy between the concentration of MCT, or the mixture, that could suppress the growth of tumor cells and the concentration that inhibited the cytotoxicity of LAK cells. Moreover, no damage was observed in PBL or LAK cells or in their cytotoxicity when the cells were incubated with TG for 2 h a day. Thus, short-term contact with TG could inhibit tumor growth while immune system was maintained within normal range. Clinically fine control of the concentration of injected triglycerides, especially MCT, can be expected to provide potent antitumor effect and maintenance of normal immune system.

The expression of urokinase type plasminogen activator is a novel prognostic factor in dukes B and C colorectal cancer

Urokinase type plasminogen activator (u-PA) secreted by cancer cells is considered to play a key role in promoting invasion and metastasis of cancer cells. This study was designed to evaluate the expression and prognostic value of u-PA in Dukes B and C colorectal cancer. u-PA expression was investigated in 57 Dukes B or C colorectal cancers using a monoclonal antibody against u-PA. u-PA expression was mainly observed on the cytoplasm of cancer cells, and was associated with relapse, especially hematogenous metastasis (p=0.025, the chi2 test). Patients with high u-PA expression had a lower rate of DFS (9/22 events) compared to those with low u-PA expression (6/35 events) (p=0.061, log-rank test). This study demonstrated that u-PA expression might be a novel prognostic factor in Dukes B and C colorectal cancer.

Immunohistochemical Detection of P-glycoprotein in Breast Cancer and Its Significance as a Prognostic Factor

Overexpression of P-glycoprotein (Pgp) in tumors is one of the major mechanisms which mediates the multidrug resistance (MDR) phenotype. To evaluate the prognostic significance of Pgp in breast cancer, Pgp expression was examined in paraffin-embedded tissue sections of 94 breast cancer specimens by immunohistochemistry. Tissue specimens were obtained by mastectomy without preoperative chemotherapy. UIC2 monoclonal antibody which recognizes an extracellular epitope of human Pgp was employed. Of the 94 breast cancer specimens, 35(37.2%)were positive for Pgp expression. Pgp expression had no correlation with menopausal or hormone receptor status, axillary Iymph node involvement or tumor size. However, a significant correlation was observed between Pgp expression and disease relapse (p=0.0322). Pgp-positive patients showed a significantly shorter disease-free survival period than Pgp-negative patients by the Kaplan-Meier method (p=0.0433). These results suggest that immunohistochemical detection of Pgp in breast cancer tissue may have prognostic value after radical operation.

Thrombomodulin is a new biological and prognostic marker for breast cancer: an immunohistochemical study

BACKGROUND

Thrombomodulin (TM) is a natural anticoagulant which inhibits thrombin. Recent studies have reported that TM is correlated with vascular diseases and a few cancers. The aim of this study was to evaluate the role and the prognostic value of TM in breast cancer.

PATIENTS AND METHODS

TM expression in samples from 60 invasive breast cancer patients was examined immunohistochemically with a polyclonal antibody against TM.

RESULTS

TM staining was observed mainly on both the cytoplasm and cell surface in cancer cells and on endothelial cells around or in cancer tissue. TM expression in cancer cells was not correlated with the clinicopathological features. However, low TM expression was significantly correlated with a high relapse rate (p = 0.047 by the chi 2 test and 0.05 by the Kaplan-Meier method).

CONCLUSIONS

TM might play an active role in cancer invasion and metastasis, and serve as a new prognostic factor in invasive breast cancer.

Urokinase type plasminogen activator receptor is a novel prognostic factor in breast cancer

BACKGROUND

There have been many reports that the u-PA system plays an important role in cancer invasion and metastasis. The binding of u-PA to its specific cell-surface receptor, u-PAR, is necessary for the activation of u-PA system. The aim of this study is to evaluate the role and the prognostic value of u-PAR in cancer invasion and metastasis.

PATIENTS AND METHODS

u-PAR expression in 104 breast cancers was investigated immunohistochemically using a monoclonal antibody against u-PAR.

RESULTS

u-PAR expression was mainly observed both on cancer cells and stromal cells. Patients with high u-PAR expression in cancer cells or stromal cells had a high relapse rate compared with patients with low u-PAR expression by the Kaplan-Meier method (p = 0.035 and 0.011, respectively). In uni- and multivariate analysis, u-PAR expression in stromal cells was significantly correlated with relapse (p = 0.017 and 0.043, respectively).

CONCLUSIONS

This study has shown that not only cancer cells but also stromal cells have an important roles in breast cancer invasion and metastasis, and that u-PAR expression in cancer cells and stromal cells might be a novel prognostic factor in breast cancer.

The N-terminal region of hepatitis C virus-encoded NS5A is important for NS4A-dependent phosphorylation

We previously showed that two proteins, a 56-kDa protein (p56) and a 58-kDa protein (p58), are produced from the hepatitis C virus (HCV) nonstructural 5A region (NS5A) and that the production of p58 is enhanced by the presence of NS4A (T. Kaneko, Y. Tanji, S. Satoh, M. Hijikata, S. Asabe, K. Kimura, and K. Shimotohno, Biochem. Biophys. Res. Commun. 205:320-326, 1994). Both proteins have phosphorylated serine residues, some of which are located in the C-terminal region. In p58, phosphorylation of serine residues in the central region of HCV NS5A is important for production of p58 in an NS4A-dependent manner. To clarify the mechanism of NS5A phosphorylation, in particular phosphorylation in the central region, phosphorylation of deleted and mutated forms of NS5A was analyzed using a transient protein production system in cultured cells in the presence or absence of NS4A. Association of the NS5A region from amino acids 2135 to 2139 with NS4A was important for NS4A-dependent phosphorylation of NS5A.

Possible involvement of calpain in the growth of estrogen receptor positive breast cancer cells

Calpain (Ca2(+)-activated neutral protease, EC 3.4.22.17) has been reported to hydrolyze the estrogen receptor (ER). However, there has been no report available regarding the role of calpain in the growth of breast cancer cells. To investigate the role of calpain in the growth of various breast cancer cell lines, we employed a synthetic peptide, calpeptin, which is a cell permeable specific inhibitor of calpain. Calpeptin inhibited the cell growth of ER positive breast cancer cells, such as MCF-7, T-47D, and ZR-75-1 in a dose dependent manner in the presence of E2. However, the growth of ER negative breast cancer cells, MDA-MB-231, was not inhibited by calpeptin. It is suggested that calpain plays an important role in the growth of ER positive breast cancer cells.

Phosphorylation of hepatitis C virus-encoded nonstructural protein NS5A

Two proteins, a 56-kDa protein (p56) and a 58-kDa protein (p58), are produced from the hepatitis C virus (HCV) nonstructural region 5A (NS5A). Recently, we found that both proteins are phosphorylated at serine residues and that p58 is a hyperphosphorylated form of p56. Furthermore, hyper-phosphorylation depends on the production of an intact form of the HCV NS4A protein. To clarify the nature of NS5A phosphorylation, pulse-chase analysis was performed with a transient protein production system in cultured cells. The study indicated that basal and hyperphosphorylation of NS5A occurred after proteolytic production of NS5A was complete. In an attempt to identify the location of the hyperphosphorylation sites in p58, proteins with sequential deletions from the C-terminal region of NS5A and with mutations of possible phosphorylated serine residues to a neutral amino acid, alanine, were constructed. The deleted or mutated proteins were then tested for hyperphosphorylation in the presence of the NS4A product. Here, we report that serine residues 2197, 2201, and/or 2204 are important for hyper-phosphorylation. Important sites for basal phosphorylation were identified in the region from residues 2200 to 2250 and in the C-terminal region of the NS5A product. A subcellular localization study showed that most of the NS5A products were localized in the nuclear periplasmic membrane fraction.

The N-terminal region of hepatitis C virus nonstructural protein 3 (NS3) is essential for stable complex formation with NS4A

Hepatitis C virus proteins are produced by proteolytic processing of the viral precursor polyprotein that is encoded in the largest open reading frame of the viral genome. Processing of the nonstructural viral polyprotein requires the viral serine-type proteinase present in nonstructural protein 3 (NS3). The cleavage of the junction between NS4B and NS5A is mediated by NS3 only when NS4A is present. NS4A is thought to be a cofactor that enhances the cleavage efficiency of NS3 in hepatitis C virus protein-producing cells. Stable NS3-NS4A complex formation required the N-terminal 22 amino acid residues of NS3. This interaction contributed to stabilization of the NS3 product as well as increased the efficiency of cleavage at the NS4B/5A site. The N-terminal 22 amino acid residues fused to Escherichia coli dihydrofolate reductase also formed a stable complex with NS4A. NS3 derivatives which lacked the N-terminal 22 amino acid residues showed drastically reduced cleavage activity at the NS4B/5A site even in the presence of NS4A. These data suggested that the interaction with NS4A through the 22 amino acid residues of NS3 is primarily important for the NS4A-dependent processing of the NS4B/5A site by NS3.

Bacterial expression and analysis of cleavage activity of HCV serine proteinase using recombinant and synthetic substrate

HCV encoding serine proteinase was expressed in E. coli as a fused form with maltose binding protein (MBP) and a six histidine tag. The enzyme was partially purified by using affinity chromatography for these fused peptides. Proteolytic cleavage activity of the partially purified enzyme was detected by means of an assay using both a recombinant protein and a synthetic peptide substrate which had an amino acid sequence corresponding to the most efficient cleavage site in vivo, the NS5A-NS5B junction. The cleavage occurred at the same site that was reported before.