CD44-positive Cancer Stem-like Cells as a Potential Source of Peritoneal Metastasis After Surgery

BACKGROUND/AIM

The role of CD44 in gastric cancer-derived peritoneal metastasis is currently unknown. It was previously shown that viable, tumorigenic cancer cells are spilled into the peritoneal cavity during surgery, providing a potential cause of peritoneal recurrence after surgery. The purpose of this study was to elucidate the mechanism of peritoneal metastasis of gastric cancer through the expression of CD44 and to propose a method for preventing peritoneal recurrence.

MATERIALS AND METHODS

Gastric cancer cell line MKN-45 was sorted into CD44+ and CD44- cells and then injected intraperitoneally into NOD/ShiJic-scidJcl mice. Differences in tumor-initiating capacity between the two groups were assessed using in vivo limiting dilution assays. Tumors harvested from both groups were examined for CD44 and ALDH1A1 expression using immunohistochemistry. The effects of CD44 blockade with anti-CD44 antibody on cell invasion and peritoneal metastasis formation in vivo were assessed.

RESULTS

CD44+ cells showed significantly higher efficiency in initiating peritoneal tumor than CD44- cells. Blockade of CD44 significantly reduced peritoneal dissemination of CD44+ cells in vivo, indicating that the CD44 function of intraperitoneally disseminated cancer cells helped promote the formation of peritoneal metastasis. The margin of established tumors showed clusters of cells co-expressing CD44 and ALDH1A1. Peritoneally administered CD44- cells resulted in peritoneal metastases consisting of CD44+ and CD44- cancer cells.

CONCLUSION

CD44 expressing cells are a potential source of peritoneal metastasis after surgery and could be a promising target for preventing peritoneal recurrence.

Impact of Preoperative Muscle Mass Maintenance and Perioperative Muscle Mass Loss Prevention After Pancreatectomy: Association Between Perioperative Muscle Mass and Postoperative Nutritional Status

OBJECTIVES

We investigated how preoperative sarcopenia and perioperative muscle mass changes affect postoperative nutritional parameters in patients undergoing pancreatectomy.

METHODS

This study included 164 patients undergoing pancreatectomy between January 2011 and October 2018. Skeletal muscle area was measured by computed tomography before and 6 months after surgery. Sarcopenia was defined as the lowest sex-specific quartile, and patients with muscle mass ratios less than -10% were classified into the high-reduction group. We examined the relationship between perioperative muscle mass and postoperative nutritional parameters 6 months after pancreatectomy.

RESULTS

There were no significant differences in nutritional parameters between the sarcopenia and nonsarcopenia groups at 6 months after surgery. In contrast, albumin (P < 0.001), cholinesterase (P < 0.001), and prognostic nutritional index (P < 0.001) were lower in the high-reduction group. According to each surgical procedure, albumin (P < 0.001), cholinesterase (P = 0.007), and prognostic nutritional index (P < 0.001) were lower in the high-reduction group of pancreaticoduodenectomy. In distal pancreatectomy cases, only cholinesterase (P = 0.005) was lower.

CONCLUSIONS

Postoperative nutritional parameters were correlated with muscle mass ratios but not with preoperative sarcopenia in patients undergoing pancreatectomy. Improvement and maintenance of perioperative muscle mass are important to maintain good nutritional parameters.

Pleural empyema caused by dropped gallstones after laparoscopic cholecystectomy for acute cholecystitis: a case report

BACKGROUND

Dropped gallstones during laparoscopic cholecystectomy (LC) sometimes induce postoperative infectious complications. However, pleural empyema rarely occurs as a complication of LC.

CASE PRESENTATION

We present the case of a 66-year-old woman with right pleural empyema. She previously underwent LC for acute gangrenous cholecystitis 11 months ago. The operative report revealed iatrogenic gallbladder perforation and stone spillage. The bacterial culture of the gallbladder bile was positive for Escherichia coli. Chest and abdominal computed tomography revealed right pleural effusion, perihepatic fluid collection, and multiple small radiopaque density masses. Although ultrasound-guided transthoracic drainage was performed, the drainage was incomplete, and systemic inflammatory reaction persisted. Consequently, thoracotomy and laparotomy with gallstone retrieval were performed, and the patient recovered completely. The patient has remained well without complications after 14 months of follow-up.

CONCLUSIONS

We report a rare case of pleural empyema caused by dropped gallstones after LC. This case emphasized the importance of completely retrieving the dropped gallstones to prevent late infectious complications after LC.

Aggressive Intervention of Pancrelipase After Pancreatectomy Prevents Deterioration of Postoperative Nutritional Status

OBJECTIVES

This study aimed to investigate the effect of early administration of delayed-release high-titer pancrelipase.

METHODS

The medical records of 120 patients who had undergone pancreatectomy with computed tomography (CT) before and 6 months after surgery were retrospectively reviewed. Delayed-release high-titer pancrelipase were administered daily starting on postoperative day 3, which was defined as the EP group. The postoperative nutritional status and CT attenuation values of the liver were compared between the EP and control groups.

RESULTS

Thirty-three patients (28%) were categorized into the EP group. With regard to the postoperative nutritional status 6 months after surgery, the body mass index, total lymphocyte count, and Onodera's prognostic nutritional index were higher, and controlling nutritional status score was lower in the EP group than that in the control group. The CT attenuation values of the liver were not significantly different. After propensity score matching analysis, body mass index (20.7 vs 19.2, P = 0.049) and Onodera's prognostic nutritional index (47.9 vs 44.2, P = 0.045) were significantly higher, and controlling nutritional status score was significantly lower in the EP group than that in the control group (1 vs 3, P = 0.046).

CONCLUSIONS

The early administration of pancrelipase after pancreatectomy improved nutritional status after pancreatectomy.

Pathological complete response in a patient with metastatic pancreatic acinar cell carcinoma who received a chemotherapy regimen containing cisplatin and irinotecan

Pancreatic acinar cell carcinoma is a rare tumor of the pancreas, and patients with such tumors rarely have a pathological complete response to treatment. Herein, we present a case involving a 48-year-old woman with a pancreatic tail mass. The pancreatic mass was connected to splenic and portal vein thrombosis. Distal pancreatectomy and removal of portal vein tumor thrombosis were performed. Ten months after surgery, multiple liver metastases and local recurrence in the pancreatic bed were detected, and chemotherapy was administered through the administration of a regimen containing both cisplatin and irinotecan. After seven courses of the cisplatin-plus-irinotecan regimen had been administered, computed tomography revealed that the patient had a partial response to treatment. Radical resection of multiple liver metastases and the locally recurrent tumor was performed. Pathological examination did not reveal the presence of carcinoma in any of the resected specimens. Thus, this case involves a pathological complete response in a patient with metastatic pancreatic acinar cell carcinoma who received a regimen containing both cisplatin and irinotecan. Our findings reveal that the administration of the cisplatin-plus-irinotecan regimen may be an option for the management of such tumors.

Attenuation around the gallbladder on plain abdominal computed tomography as a predictor of surgical difficulty in laparoscopic cholecystectomy

PURPOSE

This study examined whether abdominal plain computed tomography (CT) can predict surgical difficulty in acute cholecystitis.

METHODS

We retrospectively analyzed 84 consecutive patients who underwent laparoscopic cholecystectomy for acute cholecystitis between January 2015 and December 2018. We distinguished three degrees of surgical difficulty based on the operative time and blood loss: difficult, both ≥120 minutes and ≥ 100 mL, respectively (n = 27); moderate, either ≥120 minutes or ≥ 100 mL, respectively (n = 30); and easy, both <120 minutes and < 100 mL, respectively (n = 27). We calculated the attenuation around the gallbladder on CT before surgery and compared the values among the three groups.

RESULTS

Mean age, albumin levels, C-reactive protein levels, and the CT attenuation around the gallbladder (P < .001) were significantly different between groups. The surgical difficulty was unrelated to the timing of surgery. The postoperative complications were more frequent in operations more than 72 hours after disease onset (P = .04) and with CT attenuation around the gallbladder of ≥1.4 (P = .036).

CONCLUSION

High attenuation around the gallbladder on plain CT predicted a high surgical difficulty of laparoscopic cholecystectomy. We recommend measuring the CT attenuation around the gallbladder in patients with acute cholecystitis.

Cancer-derived Exosomes Activate Immune Surveillance and Suppress Peritoneal Metastasis of Murine Colonic Cancer

BACKGROUND

Colonic cancer is associated with a low incidence of peritoneal metastasis compared with gastric cancer; however, the reason for this remains unclear. In this study, a model of peritoneal dissemination using the CT26 murine colon cancer cell line was used to analyze the physiological roles of cancer-derived exosomes.

MATERIALS AND METHODS

Exosomes were collected from the supernatant of CT26 cell culture by ultracentrifugation. The number of peritoneal disseminations in two mouse models of colonic cancer pre-administered exosomes or phosphate-buffered saline were compared.

RESULTS

Cancer-derived exosomes suppressed peritoneal dissemination compared to phosphate-buffered saline. After administration of exosomes, the number of intraperitoneal macrophages and the expression of inducible nitric oxide synthase increased. Furthermore, cancer-derived exosomes increased activated natural killer cells and interferon-γ expression.

CONCLUSION

Tumor-derived exosomes from colonic cancer may suppress peritoneal metastasis via an immunological mechanism.

Vimentin Expression in Tumor Microenvironment Predicts Survival in Pancreatic Ductal Adenocarcinoma: Heterogeneity in Fibroblast Population

BACKGROUND

The tumor microenvironment, including cancer-associated fibroblasts (CAFs), plays various clinical roles in cancer growth. CAFs are a heterogeneous population and express a variety of mesenchymal markers. However, the clinical roles for CAFs expressing different markers in pancreatic ductal adenocarcinoma (PDAC) remain unknown.

METHODS

We reviewed 67 resected PDAC patients who had not received preoperative therapy. Each primary tumor was analyzed for vimentin and α-smooth muscle actin (α-SMA) expression by immunohistochemical and dual immunofluorescence staining.

RESULTS

There was no correlation between the percentage of cells expressing vimentin and α-SMA in the tumor stroma (Pearson's correlation coefficient: r = 0.171). Higher vimentin expression (p = 0.018) was associated with significantly shorter overall survival in PDAC patients. Using dual immunofluorescence staining, vimentin-positive CAFs were divided into two subpopulations: co-expression of α-SMA, and no co-expression of α-SMA. In PDAC, the level of co-expression had no effect on survival using univariate analysis (median survival time, 33.3 months for low co-expression vs. 18.2 months for high co-expression; log-rank, p = 0.143). However, multivariate analysis clarified that CAFs expressing vimentin alone was an independent predictor of poor survival (p = 0.014; hazard ratio, 2.305; 95% confidence interval, 1.181-4.497).

CONCLUSIONS

Vimentin-positive CAFs without co-expression of α-SMA were associated with poor survival in PDAC, and CAFs possessed molecular and functional heterogeneity in this disease.

USP15 inhibits HPV16 E6 degradation and catalytically inactive USP15 has reduced inhibitory activity

High-risk human papillomaviruses (HPVs) possess transforming activity leading to development of the cancer, including oropharyngeal, anal, penile, vulvar, vaginal, and cervical cancer. The stability of E6 is essential for its complete function as an oncoprotein. Using the yeast two-hybrid system, we identified ubiquitin-specific protease 15 (USP15) as an HPV16 E6-interacting protein. USP15 cleaves polyubiquitin chains of HPV16 E6 and/or ubiquitin precursors. Our results indicate that USP15 could increase the level of HPV16 E6 by inhibiting E6 degradation. USP15 inhibited the degradation of HPV16 E6 in dose-dependent manner. In contrast, catalytically inactive mutants of USP15 had a reduced inhibitory effect on E6 degradation. In particular, USP15 mutants of all three cysteine boxes and the NHL mutant of the KRF box had a drastically reduced inhibitory effect on HPV16 E6 degradation. In addition, HPV16 E6 mRNA was not induced by USP15; therefore, HPV16 E6 appears to be post-translationally regulated. These results suggest that USP15 has the ability to stabilize E6 as a deubiquitinating enzyme, and as an oncoprotein affects biological functions in infected human cells.

[A case of breast cancer with repeated cardiac dysfunction due to trastuzumab]

Here we present a case of breast cancer in which cardiac dysfunction had previously been observed on trastuzumab(TRS) administration; the condition then improved but reoccurred on readministration of TRS. A 52-year-old woman received preoperative chemotherapy for StageIIIC left breast cancer(fluorouracil, epirubicin and cyclophosphamide followed by docetaxel and TRS), and then underwent partial mastectomy and axillary lymph node dissection. For adjuvant therapy, she received endocrine therapy and TRS. Radiation therapy was administered to the left residual breast. The patient complained about palpitation in the 5th cycle of TRS, and left ventricle ejection fraction(LVEF)decreased to 45.3% from 64%. Therefore, we stopped TRS administration. Palpitation improved, and LVEF increased to 53% after 2 months. TRS was administered again; however, palpitation reoccurred and LVEF decreased to 44%. TRS administration was once again discontinued. However, according to the HERA trial report regarding patients with a history of anthracycline and radiation therapy, TRS administration could be resumed when LVEF is greater than 50%, but we should be more careful during readministration of TRS.

Tetrahedral magnetic order and the metal-insulator transition in the pyrochlore lattice of Cd2Os2O7

Cd2Os2O7 shows a peculiar metal-insulator transition at 227 K with magnetic ordering in a frustrated pyrochlore lattice, but its magnetic structure in the ordered state and the transition origin are yet uncovered. We observed a commensurate magnetic peak by resonant x-ray scattering in a high-quality single crystal. X-ray diffraction and Raman scattering experiments confirmed that the transition is not accompanied with any spatial symmetry breaking. We propose a noncollinear all-in-all-out spin arrangement on the tetrahedral network made of Os atoms. Based on this we suggest that the transition is not caused by the Slater mechanism as believed earlier but by an alternative mechanism related to the formation of the specific tetrahedral magnetic order on the pyrochlore lattice in the presence of strong spin-orbit interactions.

Effect of direct retainer and major connector designs on RPD and abutment tooth movement dynamics

Designs of removable partial dentures are suggested to affect the mobility of abutment teeth and removable partial denture (RPD) during oral functions. This study aimed to examine the effect of direct retainer and major connector designs on RPD dynamics under simulated loading. Six different Kennedy class II maxillary RPDs were fabricated on a maxillary model. These dentures involved 3 different direct retainers (wrought-wire clasp, RPA clasp, and conical crown telescopic retainer) and 2 different major connectors (Co-Cr major connector and heat-cured acrylic resin with a metal strengthener). Using an experimental model with simulated periodontal ligaments and mucosa that were fabricated using silicone impression material, three-dimensional displacements of the RPDs were measured under a simulated 30-N loading with a displacement transducer type M-3. Significant effects of "direct retainer design" on bucco-palatal displacements and "major connector" on mesio-distal displacements were revealed by 2 x 3 two-way analysis of variance of abutment teeth movements (P < 0.001 and P = 0.002, respectively). Additionally, analysis of variance of RPD displacements revealed significant effects of "direct retainer design" on corono-apical displacements and "major connector" on mesio-distal displacements (P = 0.001 and P = 0.028, respectively). Rigid direct retainers and rigid major connectors decrease the movements of both abutment tooth and RPD.

Blockade of secondary lymphoid tissue chemokine exacerbates Propionibacterium acnes-induced acute lung inflammation

Chemokine-chemokine receptor interaction plays an essential role in leukocyte/dendritic cell (DC) trafficking in inflammation and immune responses. We investigated the pathophysiological roles of secondary lymphoid tissue chemokine (SLC; CCL21) and macrophage inflammatory protein-2 (MIP-2) in the development of acute pulmonary inflammation induced by an intratracheal injection of Propionibacterium acnes in mice. Immunohistochemical studies revealed that SLC was constitutively expressed in the peribronchial areas and perivascular lymphatics in normal mice. MIP-2-positive cells were observed in alveolar spaces in mice challenged with P. acnes. Both neutralization Abs against MIP-2 and CXC chemokine receptor 2 alleviated the P. acnes-induced pulmonary inflammation when injected before P. acnes Ag challenge. On the other hand, polyclonal anti-SLC Abs (pAbs) exacerbated the pulmonary inflammation. The numbers of mature DCs (MHC class II +, CD11c+, and CD86+) as well as macrophages and neutrophils in the P. acnes Ag-challenged lungs were increased, whereas the number of CD4+ T cells, including memory T cells, was decreased. The numbers of mature and proliferating CD4+ T cells (bromodeoxyuridine(+)CD4+) in regional lymph nodes were decreased in mice injected with anti-SLC pAbs compared with those in mice treated with control Abs. An in vitro proliferation assay confirmed the impairment of the Ag-specific T cell response in regional lymph nodes of mice treated with anti-SLC pAbs. These results indicate for the first time a regulatory role for SLC-recruited mature DCs in bridging an acute inflammatory response (innate immunity) and acquired immunity in the lung.

Acid hydrolase activity of cultured bovine oligodendrocytes

We measured the activity of several acid hydrolases of cultured oligodendrocytes prepared from adult bovine brain white matter to clarify the biochemical basis of bovine oligodendrocytes in vitro. Lysosomal enzyme activities were assayed by using 4-methylumbelliferyl glycosides as substrates. Lysosomal enzyme activities became higher at 8-11 days in vitro (DIV) than 4 DIV. The enrichment in acid hydrolase specific activities in oligodendrocytes may be associated with lysosomal origin of myelin-like membranes.

Long-term follow-up of sustained responders to interferon therapy, in patients with chronic hepatitis C

Interferon (IFN) therapy has been proven to induce the normalization of serum alanine aminotransferase (ALT) levels and to eradicate the hepatitis C virus (HCV) in some patients with chronic hepatitis C, and these patients are usually defined as 'sustained responders'. However, there have been some reports of hepatocellular carcinoma (HCC) in these patients, and the development of HCC remains life-threatening in patients who clear HCV. We analysed the long-term prognoses of patients with chronic hepatitis C in whom HCV was eradicated with IFN. We investigated 392 sustained responders to IFN therapy, from 1,277 patients with chronic HCV infection who received IFN treatment at one of our institutions between April 1989 and March 1999. We analysed the medical records and looked for the development of HCC. About 30% of the sustained responders had been lost to follow-up 3 years after the end of IFN therapy, and the follow-up rate of sustained responders was significantly lower than that of non-sustained responders (P < 0.0001). HCC were found in eight patients: in seven patients HCC developed within 5 years after completion of IFN therapy; but in one patient, a single HCC less than 3 cm in diameter was detected between 7 and 8 years after completion of IFN. Of the five patients who had regular medical follow-up, the HCC was solitary, and the patients survived without any evidence of recurrence. Of the three patients who had not been followed-up, two died from HCC and HCC recurred in the third. These results suggest that HCC can develop in sustained responders and that sustained responders should be followed-up closely after completion of IFN so that HCC may be detected at an early stage. The optimal duration of the follow-up period of the sustained responders remains unclear. Additional prospective studies are required in order to establish an appropriate follow-up protocol for sustained responders to IFN.

Unglycosylated Trk protein does not co-localize nor associate with ganglioside GM1 in stable clone of PC12 cells overexpressing Trk (PCtrk cells)

Our previous studies have shown that acidic glycosphingolipid, ganglioside GM1 (GM1), is an endogenous regulator of high affinity nerve growth factor receptor, Trk, which is an essential factor for the normal development and differentiation of neuronal cells by forming a complex with Trk. GM1 is also known to be a major constituent of caveola or glycosphingolipid-enriched microdomain (GEM) of the plasma membrane. In order to study the effect of the glycosylation of Trk on the formation of GM1-Trk complex and subcellular distribution of this protein, we generated PC12 cells stably overexpressing Trk (PCtrk). Pretreatment of this stable clones with tunicamycin, a potent inhibitor of N-glycosylation, caused the appearance of unglycosylated Trk core protein. These unglycosylated Trk can hardly respond to its ligand, NGF. Sucrose density gradient analysis revealed that unglycosylated Trk core protein was recovered in high density fractions, whereas most of GM1 is present in low density fractions corresponding to caveola or GEM fractions. Moreover, these unglycosylated Trk proteins lose their ability to form a complex with GM1, although GM1 is present in the same high density fractions. These data strongly suggest that spatial segregation of GM1 from the Trk protein by the inhibition of the glycosylation of Trk might be an important molecular mechanism for the unresponsiveness to NGF. Moreover, the binding site of GM1 in the Trk protein might act as an important determinant for the normal trafficking of the Trk protein within the cells.

Pivotal role of CCR1-positive leukocytes in bleomycin-induced lung fibrosis in mice

We have investigated the involvement of chemokine receptor CCR1-positive cells in bleomycin-induced lung injury, a model of pulmonary fibrosis. After bleomycin challenge in C57BL/6J mice, the expression of CCR1 mRNA increased and peaked at day 7, which paralleled to the expression of its ligands, macrophage-inflammatory protein-1 alpha and RANTES. Immunohistochemical study showed that CCR1-positive cells accumulated in the interstitial inflammatory site. Furthermore, the treatment of anti-CCR1 Ab significantly reduced the accumulation of inflammatory cells and collagen deposition, resulting in dramatic improvement of survival. These results suggest that CCR1-positive cells play significant roles in the pathogenesis of pulmonary fibrosis subsequent to bleomycin-induced lung injury, and that CCR1 could be a novel molecular target for intervention therapy against pulmonary fibrosis.

Alteration of ganglioside composition by stable transfection with antisense vectors against GD3-synthase gene expression

Gangliosides are ubiquitous components of mammalian cells. Their expression is frequently altered in many tumor types. We previously showed that alteration of the ganglioside composition often resulted in changes in cellular morphology and differentiation of cultured cells. In this study, we targeted sialyltransferase gene expression by the antisense knockdown experiment, and the results showed that inhibition of the expression of gangliosides GD3 and O-acetylated GD3 (OAc-GD3) in the neuroblastoma F-11 cells greatly reduced the tumor growth in nude mice. The sense and antisense vectors containing either a 5' end fragment or the entire sequence of the cDNA coding for GD3-synthase were prepared and used in separate experiments to transfect the F-11 cells which express high levels of gangliosides GD3 and OAc-GD3. Single clones were isolated and expanded. Both the activity of the GD3-synthase and the concentrations of GD3 and OAc-GD3 in the antisense-transfected cells were dramatically decreased as a result of transfection with the antisense expression vectors. Further characterization of the antisense-transfected cells showed reduced rates of cell growth and neurite formation and changes in cellular morphology. When the cells were inoculated in athymic nude mice, the tumor growth rate was remarkably suppressed although the tumor incidence was not affected by the altered ganglioside composition. These results indicate that the tumor-associated ganglioside(s) is(are) involved in regulation of tumor growth, probably through the stimulation of angiogenesis of the tumor.

Glucosylceramide synthase inhibitor inhibits the action of nerve growth factor in PC12 cells

Previous studies have shown that the ceramide analogue, D-threo-1-phenyl-2-decanoylamin-3-morpholino-propanol (D-PDMP), inhibits glucosylceramide synthase and thus leads to extensive depletion of glycosphingolipids derived from glucosyl ceramide. Our previous studies have shown that cholera toxin B subunit, which specifically binds to the cell surface ganglioside GM1, and GM1 itself can enhance the action of nerve growth factor (NGF) in responsive cells by enhancing the NGF-induced autophosphorylation of the high affinity NGF receptor, Trk. Using D-PDMP, we examined the effects of the inhibition of the biosynthesis of glycosphingolipids on intracellular NGF signaling pathway. D-PDMP was found to inhibit NGF-induced neurite outgrowth of PC12 cells. Moreover, D-PDMP clearly inhibited NGF-induced autophosphorylation of Trk and prevented the activation of phosphatidylinositol 3-kinase and mitogen-activated protein kinase, downstream targets of Trk-initiated intracellular protein kinase cascades. These effects of D-PDMP were abolished by the addition of GM1 but not by the addition of other ganglioside subspecies to the culture medium. Furthermore, the effect of D-PDMP seemed to be specific for the Trk receptor, because intracellular signaling pathway of epidermal growth factor was not affected by D-PDMP. Dimethylsphingosine and the cell-permeable analogue, C2-ceramide, did not show such a strong inhibitory effect on neurite outgrowth or on the autophosphorylation of Trk. The present results and our previous observations clearly demonstrate that Trk requires endogenous gangliosides, especially GM1, for its normal function in mediating the neurotrophic activity of NGF at least in PC12 cells.

Sulfoglucuronosyl glycolipids as putative antigens for autoimmune inner ear disease

Autoimmune inner ear disease is diagnosed based on clinical history of fluctuating but progressive sensorineural hearing loss (SNHL) with or without vestibular symptoms occurring over weeks to months. An initial response to steroids or immunosuppressive drugs usually reverses the hearing loss. In search of specific diagnostic and therapeutic markers for autoimmune inner ear diseases, we investigated serum anti-glycolipid antibody activities in these patients by two different methods, HPTLC-immunoblotting and ELISA. We found that 37 out of 74 patients of clinically diagnosed autoimmune inner ear disease (30 of sensorineural hearing loss (SNHL) (group I), 14 of vestibular symptoms only (group II), 30 of Menieres symptoms (with both hearing loss and vestibular symptoms) (group III)) showed positive anti-sulfoglucuronosyl lactosaminyl paragloboside (SGLPG) antibody titers (p < 0.001). On the other hand, anti-sulfoglucuronosyl paragloboside (SGPG) titers were not elevated in these conditions. In contrast, only 3 out of 56 pathological control and 2 out of 28 healthy volunteers had measurable anti-SGLPG antibody titers. We further analyzed the localization of SGLPG in the auditory pathway and found that the antigens existed exclusively in inner ear and the eighth nerve, but not in pons, cerebellum, nor cerebrum. We conclude that the anti-SGLPG antibody represents a novel diagnostic marker for autoimmune inner ear disease and may participate in the pathogenesis of this disease.

[Color Doppler signal enhancement with SH/TH-508 in pancreatic tumors]

In this report, we showed the efficacy of a new contrast agent (SH/TA-508, Schering AG, Germany) for color Doppler imaging of the pancreatic tumors. In pancreatic ductal cancer, no enhancement of the lesion was observed, but vascular invasion by cancer became to be easily evaluated. On the other hand, hypervascular tumors such as islet cell tumor and cystadenocarcinoma, were increased in color Doppler signals of vessels by SH/TA-508. We concluded that SH/TA-508 was useful for evaluating the vascular invasion by pancreatic cancer as well as vascularity of hypervascular mass and solid component of cystic neoplasma.

[Coxsackie virus B4 encephalitis in a young female who developed mental symptoms, and consciousness disturbance, and completely recovered]

An 18-year-old female had common cold and insomnia in early March 1987. Later, abnormal speech and behavior, emotional incontinence, anorexia and consciousness disturbance appeared. On March 19, she was admitted to our hospital in semi-comatose state. Myoclonus-like movement on hands was observed, and epileptic attacks with tonic and clonic convulsions occasionally occurred. There were no neurological findings that suspected cerebral focal lesions. The respiration was assisted through tracheal intubation. Laboratory examinations showed inflammatory reactions (CRP+2, WBC 10,600) and transient high levels serum CK (6,215 IU). As she had bradycardia (30-40/min) with complete AV block on ECG, the pacemaker was implanted. The complication of myocarditis was suspected. EEG showed bilateral slow waves (3-6Hz), dominantly in frontal areas. Brain CT and CSF examinations were normal. After the combined administration of ara-A, dexamethasone and anti-convulsant, the consciousness level was recovered within a month. The serum antibody against coxsackie virus B4 alone was significantly increased. We concluded that coxsackie virus B4 caused acute encephalitis with mental symptoms and myocarditis with AV block. Recently, cytomegalovirus was reported to be the causative virus in a young female with non-HSV encephalitis who showed mental symptoms with good prognosis, but coxsackie virus B4 should also be considered as one of the causative viruses.

GM1 gangliosidosis type 3 with severe jaw-closing impairment

The patient had adult GM1 gangliosidosis (type 3) with severe impairment of mastication caused by dystonia of anterior digastric muscles (jaw-opener) on clenching. This is the first report on jaw dystonia severe enough to cause the masticatory impairment in adult GM1 gangliosidosis. The discordance of closing and opening muscles during mastication might be caused by a basal ganglia lesion in this disease.

Unusual gangliosidosis in emu (Dromaius novaehollandiae)

A previous study has demonstrated an unusual gangliosidosis in emu that is characterized by the accumulation of gangliosides in the brain tissues with GM3 and GM1 predominating. To provide insight into this unique disorder of emu gangliosidosis, the current study focused on analysis of neutral glycosphingolipids and gangliosides from brain and liver tissues of affected birds and healthy controls. We found not only that the total lipid-bound sialic acid content was increased three- and fourfold in the affected brain and liver, respectively, but also that the ganglioside pattern was rather complex as compared with the control. The absolute ganglioside sialic acid content was significantly increased in the diseased tissues, with the highest elevation levels of GM3 (14-fold) and GM1 (ninefold) in the affected brain. Relative increases in content of these monosialogangliosides were also significant. GM2 was only detected in the affected brain, but not in normal controls. The neutral glycosphingolipid fraction showed accumulation of many oligosylceramides, with six- and 5.5-fold increases in lactosylceramide levels for brain and liver, respectively. The level of myelin-associated galactosylceramide (GalCer) in the brain was decreased to only 41% of that in the healthy control, whereas no difference was found in liver tissues from both groups. Besides GalCer, the brain content of sulfatide (cerebroside-sulfate esters), another myelin-associated glycolipid, decreased to only 16% of the control. The loss of myelin-associated GalCer and sulfatide strongly suggests demyelination in the affected emu brain. Our overall data are consistent with the presence of a unique form of sphingolipidosis in the affected emus, perhaps with secondary demyelination, and suggest a metabolic disorder related to total sphingolipid activator deficiency.

Intrahepatic expression of pro-inflammatory cytokine mRNAs and interferon efficacy in chronic hepatitis C

To investigate the relationship between intrahepatic cytokine expression and interferon (IFN) response in chronic hepatitis C [CH(C)], interleukin (IL)-1 beta, -2, -4, -6, -8, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha and TNF-beta mRNAs were investigated semiquantitatively by reverse transcription polymerase chain reaction using serial liver biopsies taken before and after IFN-alpha treatment from 24 patients with CH(C), including 12 responders and 12 non-responders. Before IFN treatment, IL-2, TNF-beta, IFN-gamma and IL-8 mRNA were associated with severe hepatitis activity whereas IL-4 mRNA was associated with weak hepatitis activity, regardless of IFN response. IL-2, TNF-beta and IFN-gamma mRNAs were significantly greater in IFN non-responders. After IFN treatment a complete response to IFN was significantly associated with the disappearance of these pro-inflammatory cytokines, whereas non-responders retained the expression of cytokine mRNA as before IFN treatment. Our results indicated that IFN-alpha treatment may modulate the intrahepatic cytokine network, and this may be one mechanism of IFN-alpha that reduces hepatitis activity, aside from an anti-viral effect. A difference in cytokine network may be involved in IFN response in CH(C).

Expression of interferon-alpha receptor mRNA in the liver in chronic liver diseases associated with hepatitis C virus: relation to effectiveness of interferon therapy

To investigate whether interferon-alpha receptor (IFN-alpha Rc) expression was related to the effectiveness of interferon therapy in hepatitis C virus (HCV)-associated chronic liver disease (CLD). IFN-alpha Rc mRNA was investigated by reverse transcription polymerase chain reaction (RT-PCR) in liver biopsies and peripheral blood mononuclear cells (PBMCs) from 40 patients with HCV-associated CLD who subsequently received IFN-alpha therapy. IFN-alpha Rc mRNA in the liver was detected in 18 of 20 (90%) responders to IFN and in 5 of 20 (25%) non-responders (P < 0.01). In PBMCs, IFN-alpha Rc mRNA was detected in all patients regardless of response to IFN. Increased histological hepatitis activity and liver fibrosis were significantly related to the absence of IFN-alpha Rc mRNA. The HCV-RNA genotype showed no significant relationship to IFN-alpha Rc mRNA expression. Our results suggest that IFN-alpha Rc mRNA expression in the liver, but not in PBMCs, is closely associated with the effectiveness of IFN-alpha therapy in HCV-associated CLD.

Hepatitis B virus with X gene mutation is associated with the majority of serologically "silent" non-b, non-c chronic hepatitis

Hepatitis B virus (HBV) with X gene mutations has been a putative pathogen of chronic hepatitis without serological markers of known hepatitis viruses. The aim of this study was to reconfirm whether the HBV with the X gene mutation is associated with these serologically "silent" non-B, non-C (NBNC) chronic hepatitis, alcoholic liver disease (ALD) and autoimmune hepatitis (AIH). HBV DNA was amplified from serum and sequenced in 30 patients with NBNC chronic hepatitis in comparison with 20 patients with ALD and 5 patients with AIH. HBV DNA was identified in 21 patients (70%) in NBNC chronic hepatitis by nested polymerase chain reaction while only one patient (5%) in ALD and none in AIH showed HBV DNA. Eighteen (85.7%) of the 21 identified HBV DNAs had an identical 8-nucleotide deletion mutation at the distal part of the X region. This mutation affected the core promoter and the enhancer II sequence of HBV DNA and created a translational stop codon which truncated the X protein by 20 amino acids from the C-terminal end. All the HBV DNAs had a precore mutation at the 83rd nucleotide resulting in disruption of HBe antigen synthesis. These results indicate that HBV mutants are closely associated with the majority of serologically "silent" NBNC chronic hepatitis cases and the population of such mutant HBV DNAs is not uniform.

Gene expression of perforin and granzyme A in the liver in chronic hepatitis C: comparison with peripheral blood mononuclear cells

Perforin and granzyme A are the major effectors of cytotoxic T cells in cell-mediated cytotoxicity. However, there has been no report on these effectors in chronic viral hepatitis. In the present study, the expression of perforin and granzyme A mRNA was investigated by the reverse transcription polymerase chain reaction method using liver biopsy specimens and peripheral mononuclear cells (PBMC) from 21 patients with chronic hepatitis C and 5 control cases. Perforin mRNA was detected only in the liver of chronic hepatitis patients but not in the control livers. Conversely, perforin mRNA was not expressed in PBMC of the patients with chronic hepatitis (P < 0.01). Granzyme A mRNA was detected both in the liver and PBMC of all the cases including control cases. These results indicated that the perforin is an important effector molecule in the hepatocyte lysis in chronic viral hepatitis C.

Ganglioside GM1 binds to the Trk protein and regulates receptor function

Several lines of evidence have suggested that ganglioside GM1 stimulates neuronal sprouting and enhances the action of nerve growth factor (NGF), but its precise mechanism is yet to be elucidated. We report here that GM1 directly and tightly associates with Trk, the high-affinity tyrosine kinase-type receptor for NGF, and strongly enhances neurite outgrowth and neurofilament expression in rat PC12 cells elicited by a low dose of NGF that alone is insufficient to induce neuronal differentiation. The potentiation of NGF activity by GM1 appears to involve tyrosine-autophosphorylation of Trk, which contains intrinsic tyrosine kinase activity that has been localized to the cytoplasmic domain. In the presence of GM1 in culture medium, there is a > 3-fold increase in NGF-induced autophosphorylation of Trk as compared with NGF alone. We also found that GM1 could directly enhance NGF-activated autophosphorylation of immunoprecipitated Trk in vitro. Monosialoganglioside GM1, but not polysialogangliosides, is tightly associated with immunoprecipitated Trk. Furthermore, such tight association of GM1 with Trk appears to be specific, since a similar association was not observed with other growth factor receptors, such as low-affinity NGF receptor (p75NGR) and epidermal growth factor receptor (EGFR). Thus, these results strongly suggest that GM1 functions as a specific endogenous activator of NGF receptor function, and these enhanced effects appear to be due, at least in part, to tight association of GM1 with Trk.

1-Methyl-4-phenylpyridinum kills differentiated PC12 cells with a concomitant change in protein phosphorylation

1-Methyl-4-phenylpyridinum (MPP+), a selective neurotoxin, destroys the dopaminergic nigrostriatal pathway and results in a parkinsonian syndrome. Exposure of differentiated PC12 cells with nerve growth factor for 5 days to MPP+ (100 microM) for 4 h induced DNA fragmentation which is typical for the programmed cell death. MPP+ treatment (100 microM) concomitantly stimulates S6 kinase activity and resultant phosphorylation of S6 protein of 40S ribosomal subunits in the cells. Cycloheximide treatment prevents the MPP(+)-induced DNA fragmentation and enhancement of the phosphorylation of S6 protein. The present data demonstrate that neurotoxin, MPP+, kills differentiated PC12 cells by the apparent involvement of apoptotic process. Furthermore, the data strongly suggest that a change in protein phosphorylation might be involved in the signal transduction of MPP+ neurotoxicity and/or the protection from its toxicity.

[The effects of Ara-A on viral markers in duck hepatitis B virus carrier ducks]

Duck hepatitis B virus (DHBV) carrier ducks of one week old were injected with Ara-A (adenine arabinoside) of different dose including 2.5 (11 ducks), 5.0 (11), 10.0 (10) and 20.0 (10) mg/kg for 14 days. This antiviral effect showed dose-dependence up to 5.0 mg/kg and this dose seemed effective to obtain significant antiviral effect. Viral DNA and DNA polymerase activity were reduced significantly from the 1st week after starting the administration of Ara-A. This antiviral effect was maintained even at the 1st week after discontinuation of the drug. These findings were quite similar to those observed in HBV carriers. With the increasing necessity of Ara-A treatment in patients who will not respond to interferon therapy, DHBV seemed a suitable model for the investigation of the dose and antiviral effect of Ara-A treatment in humans.

Inflammation of the liver causes mutations in duck hepatitis B virus genome

To investigate whether hepatitis causes mutation in the viral genome, DNA sequences in the pre-core region of duck hepatitis B virus (DHBV) DNA were analyzed in both ducks with hepatitis and without hepatitis. Five DHBV carrier ducks were injected with DHBV particle proteins purified from duck serum with Freund's complete adjuvant (FCA) intrahepatically from 14 day posthatch for 9 weeks (immunized group). Serum was drawn at the end of the 1st and 4th week after the 1st injection of DHBV particle protein and ducks were killed at the end of the 9th week to obtain the liver. Another five ducks without treatment were used as controls. All ducks of the immunized group showed moderate to severe hepatitis at the 9th week. All ducks in the immunized group showed one mutation except one duck that showed two mutations only at the 9th week. Mutations were observed in the 5th, 13th, 21st, 22nd, and 28th codon of the pre-core region. All of them were point mutation at the 3rd base in the triplets. The frequency of mutation was different in each duck from 20% to 60% but not 100%. There was no mutations in ducks in control group. These results suggest that hepatitis causes mutation in the pre-core lesion genome of duck hepatitis B virus.

The effect of the B subunit of cholera toxin on the action of nerve growth factor on PC12 cells

Exogenous gangliosides, especially ganglioside GM1 (GM1), seem to potentiate the action of nerve growth factor (NGF). We have examined the possible regulation of the NGF signaling pathway in PC12 cells by the B subunit of cholera toxin (CTB), which binds to endogenous GM1 specifically and with a high affinity. CTB treatment (1 micrograms/ml) enhanced NGF-induced neurite outgrowth from PC12 cells, NGF-induced activation of ribosomal protein S6 kinase, and NGF-induced stimulation of trk phosphorylation. CTB plus NGF also caused a greater inhibition of [3H]thymidine incorporation into DNA than did NGF alone. These enhancing effects of CTB were blocked by the presence of cytochalasin B in the culture medium but were not affected by the presence of colchicine or by the depletion of Ca2+ in the medium. 125I-NGF binding experiments revealed that CTB treatment did not affect the specific binding of NGF to the cells. These results strongly suggest that the binding of cell surface GM1 by CTB modulates the pathway of intracellular signaling initiated by NGF and that the association of CTB with a cytoskeletal component is essential for these effects.

Genetic disease patterns in Japan: a review

Comprehensive genetic studies in which the genetic structure of a population is considered against the background of ecological factors, including environmental and social variables, often supply valuable information for the solution of a number of problems in human biology, including reproductive compensation and inbreeding depression. In the first section of this paper we consider the incidence of genetic diseases in Japan in reference to other populations. Some of the genetic disorders found elsewhere do not occur or are of lower frequencies in Japan. On the other hand, a number of genetic diseases occur at higher than usual frequencies, leading to an incidence of genetic disease of the order of about 1 per 100 in newborn Japanese. We next review the studies of consanguinity in Japan and report evidence of very high levels, ranging from 8.6% to 58.0%, for villages during the early part of the twentieth century. The rates are declining rapidly for the country but, because of traditional social values, inbreeding rates remain significant in many small villages. In the final section we consider the probable trends in the frequency of inbreeding on a worldwide basis and point out that frequencies of certain genetic diseases are likely to remain high and even increase in some societies because of various socially prescribed mating patterns.

Clinical significance of immunoglobulin A antibody to hepatitis B core antigen of polymeric and monomeric forms in chronic type B liver disease with acute exacerbation

Serum immunoglobulin A (IgA) hepatitis B core antibody (anti-HBc) was measured by a solid-phase enzyme immunoassay using monoclonal antibodies in sera from chronic carriers of hepatitis B surface antigen (HBsAg). To reinforce the clinical significance of IgA anti-HBc, levels of IgA subclasses and molecular characterization of IgA anti-HBc in sera of 13 patients in the acute exacerbation phase and the remission phase were compared. IgA anti-HBc was significantly higher in sera in the acute exacerbation phase than in the remission phase (p less than 0.025); in particular, more significant changes were observed in IgA2 anti-HBc (p less than 0.0025) and in secretory IgA anti-HBc (p less than 0.001). Analysis of molecular size distribution of IgA anti-HBc by high performance liquid chromatography showed that the elevation of polymeric IgA anti-HBc was significantly greater than that of monomeric IgA anti-HBc in the acute exacerbation phase (p less than 0.05), although there was an increase in both monomeric and polymeric IgA anti-HBc. Thus, the elevation of polymeric IgA anti-HBc suggests that the focal immune response against HBcAg in the liver and secretory IgA anti-HBc is an important marker of acute exacerbation in patients with HBsAg-positive chronic liver disease.