Impacts of liver macrophages, gut microbiota, and bile acid metabolism on the differences in iHFC diet-induced MASH progression between TSNO and TSOD mice

BACKGROUND

Tsumura-Suzuki non-obese (TSNO) mice exhibit a severe form of metabolic dysfunction-associated steatohepatitis (MASH) with advanced liver fibrosis upon feeding a high-fat/cholesterol/cholate-based (iHFC) diet. Another ddY strain, Tsumura-Suzuki diabetes obese (TSOD) mice, are impaired in the progression of iHFC diet-induced MASH.

AIM

To elucidate the underlying mechanisms contributing to the differences in MASH progression between TSNO and TSOD mice.

METHODS

We analyzed differences in the immune system, gut microbiota, and bile acid metabolism in TSNO and TSOD mice fed with a normal diet (ND) or an iHFC diet.

RESULTS

TSOD mice had more anti-inflammatory macrophages in the liver than TSNO mice under ND feeding, and were impaired in the iHFC diet-induced accumulation of fibrosis-associated macrophages and formation of histological hepatic crown-like structures in the liver. The gut microbiota of TSOD mice also exhibited a distinct community composition with lower diversity and higher abundance of Akkermansia muciniphila compared with that in TSNO mice. Finally, TSOD mice had lower levels of bile acids linked to intestinal barrier disruption under iHFC feeding.

CONCLUSIONS

The dynamics of liver macrophage subsets, and the compositions of the gut microbiota and bile acids at steady state and post-onset of MASH, had major impacts on MASH development.

Skin surface material for detecting human papillomavirus infection of skin warts

Warts, caused by human papillomavirus (HPV) infection, have various clinical presentations, making them difficult to differentiate from clavus, callus, and sometimes, squamous cell carcinoma. Although skin biopsies are the gold standard, a less-invasive method of examining these lesions is desired. Ninety patients with warts and related diseases, such as clavus and callus, were recruited to explore new differentiation methods using the surface of the warts. DNA was extracted from three types of specimens in each case: surface swab, shaved hyperkeratotic scale, and post-shaved surface swab. Total DNA was successfully extracted from these three specimens and was sufficient for subsequent HPV DNA detection. We analyzed samples for the HPV type and HPV viral load using polymerase chain reaction (PCR). Fifty-five cases were PCR-positive, and HPV1a, 2a, 4, 27, 57, and 65 were detected. The amount of HPV1a DNA produced was significantly greater than that of other HPV types. Regarding the correlation between the clinical diagnosis and HPV detection, the positive agreement rate was 90.9%, the negative agreement rate was 40.0%, and the overall agreement rate was 71.1%. Ten of the 21 cases clinically diagnosed as plantar warts were PCR-negative, especially in elderly patients. This suggests that it is difficult to distinguish plantar warts from clavus and callus in clinical practice. Although the amount of HPV DNA in the removed keratinization scale was highest for all HPV types, HPV detection by swabbing before and after shaving is also useful for follow-up as well as for differential diagnosis.

Dynamics of Liver Macrophage Subsets in a Novel Mouse Model of Non-Alcoholic Steatohepatitis Using C57BL/6 Mice

Macrophages are critical for the development of non-alcoholic steatohepatitis (NASH). Our previous findings in TSNO mouse livers showed that an iHFC (high-fat/cholesterol/cholate) diet induced liver fibrosis similar to human NASH and led to the accumulation of distinct subsets of macrophage: CD11c+/Ly6C- and CD11c-/Ly6C+ cells. CD11c+/Ly6C- cells were associated with the promotion of advanced liver fibrosis in NASH. On the other hand, CD11c-/Ly6C+ cells exhibited an anti-inflammatory effect and were involved in tissue remodeling processes. This study aimed to elucidate whether an iHFC diet with reduced cholic acid (iHFC#2 diet) induces NASH in C57BL/6 mice and examine the macrophage subsets accumulating in the liver. Histological and quantitative real-time PCR analyses revealed that the iHFC#2 diet promoted inflammation and fibrosis indicative of NASH in the livers of C57BL/6 mice. Cell numbers of Kupffer cells decreased and recruited macrophages were accumulated in the livers of iHFC#2 diet-fed C57BL/6 mice. Notably, the iHFC#2 diet resulted in the accumulation of three macrophage subsets in the livers of C57BL/6 mice: CD11c+/Ly6C-, CD11c-/Ly6C+, and CD11c+/Ly6C+ cells. However, CD11c+/Ly6C+ cells were not distinct populations in the iHFC-fed TSNO mice. Thus, differences in cholic acid content and mouse strain affect the macrophage subsets that accumulate in the liver.

The innate immune receptor RP105 promotes metabolic syndrome by altering gut microbiota composition and intestinal barrier function

Radioprotective 105 (RP105) plays a key role in the development of high-fat diet (HFD)-induced metabolic disorders; however, the underlying mechanisms remain to be understood. Here, we aimed to uncover whether RP105 affects metabolic syndrome through the modification of gut microbiota. We confirmed that body weight gain and fat accumulation by HFD feeding were suppressed in Rp105^-/- mice. Fecal microbiome transplantation from HFD-fed donor Rp105^-/- mice into HFD-fed recipient wild-type mice significantly improved various abnormalities associated with metabolic syndrome, including body weight gain, insulin resistance, hepatic steatosis, macrophage infiltration and inflammation in the adipose tissue. In addition, HFD-induced intestinal barrier dysfunction was attenuated by fecal microbiome transplantation from HFD-fed donor Rp105^-/- mice. A 16S rRNA sequence analysis indicated that RP105 modified gut microbiota composition and was involved in the maintenance of its diversity. Thus, RP105 promotes metabolic syndrome by altering gut microbiota composition and intestinal barrier function.

Impact of Vancomycin Treatment and Gut Microbiota on Bile Acid Metabolism and the Development of Non-Alcoholic Steatohepatitis in Mice

The potential roles of the gut microbiota in the pathogenesis of non-alcoholic fatty liver disease, including non-alcoholic steatohepatitis (NASH), have attracted increased interest. We have investigated the links between gut microbiota and NASH development in Tsumura-Suzuki non-obese mice fed a high-fat/cholesterol/cholate-based (iHFC) diet that exhibit advanced liver fibrosis using antibiotic treatments. The administration of vancomycin, which targets Gram-positive organisms, exacerbated the progression of liver damage, steatohepatitis, and fibrosis in iHFC-fed mice, but not in mice fed a normal diet. F4/80⁺-recruited macrophages were more abundant in the liver of vancomycin-treated iHFC-fed mice. The infiltration of CD11c⁺-recruited macrophages into the liver, forming hepatic crown-like structures, was enhanced by vancomycin treatment. The co-localization of this macrophage subset with collagen was greatly augmented in the liver of vancomycin-treated iHFC-fed mice. These changes were rarely seen with the administration of metronidazole, which targets anaerobic organisms, in iHFC-fed mice. Finally, the vancomycin treatment dramatically modulated the level and composition of bile acid in iHFC-fed mice. Thus, our data demonstrate that changes in inflammation and fibrosis in the liver by the iHFC diet can be modified by antibiotic-induced changes in gut microbiota and shed light on their roles in the pathogenesis of advanced liver fibrosis.

Roles of Macrophages in Advanced Liver Fibrosis, Identified Using a Newly Established Mouse Model of Diet-Induced Non-Alcoholic Steatohepatitis

Macrophages play critical roles in the pathogenesis of non-alcoholic steatohepatitis (NASH). However, it is unclear which macrophage subsets are critically involved in the development of inflammation and fibrosis in NASH. In TSNO mice fed a high-fat/cholesterol/cholate-based diet, which exhibit advanced liver fibrosis that mimics human NASH, we found that Kupffer cells (KCs) were less abundant and recruited macrophages were more abundant, forming hepatic crown-like structures (hCLS) in the liver. The recruited macrophages comprised two subsets: CD11c+/Ly6C- and CD11c-/Ly6C+ cells. CD11c+ cells were present in a mesh-like pattern around the lipid droplets, constituting the hCLS. In addition, CD11c+ cells colocalized with collagen fibers, suggesting that this subset of recruited macrophages might promote advanced liver fibrosis. In contrast, Ly6C+ cells were present in doughnut-like inflammatory lesions, with a lipid droplet in the center. Finally, RNA sequence analysis indicates that CD11c+/Ly6C- cells promote liver fibrosis and hepatic stellate cell (HSC) activation, whereas CD11c-/Ly6C+ cells are a macrophage subset that play an anti-inflammatory role and promote tissue repair in NASH. Taken together, our data revealed changes in liver macrophage subsets during the development of NASH and shed light on the roles of the recruited macrophages in the pathogenesis of advanced fibrosis in NASH.

Xeroderma pigmentosum complementation group G patient with a novel homozygous missense mutation and no neurological abnormalities

We describe an unusual xeroderma pigmentosum (XP) patient with a mutation in XP complementation group G, representing only the third reported Japanese XP-G patient. A 40-year-old men (XP3HM), born from consanguineous parents experienced sun sensitivity and pigmentary changes of sun-exposed skin since childhood. He developed a squamous cell carcinoma on his lower lip at the age of 40. He has neither neurological abnormalities nor Cockayne syndrome. The primary fibroblasts of the patient were hypersensitive to killing by UV (D(0) = 0.6 J/m(2)) and the post-UV unscheduled DNA synthesis was 8% of normal. Host cell reactivation complementation analysis implicated XP complementation group G. We identified a novel homozygous mutation (c.194T>C) in a conserved portion of the XPG(ERCC5) gene, resulting in a predicted amino acid change; p.L65P. We confirmed that this genetic change reduced DNA repair thus linking this mutation to increased skin cancer.

Beamline AR-NW12A: high-throughput beamline for macromolecular crystallography at the Photon Factory

AR-NW12A is an in-vacuum undulator beamline optimized for high-throughput macromolecular crystallography experiments as one of the five macromolecular crystallography (MX) beamlines at the Photon Factory. This report provides details of the beamline design, covering its optical specifications, hardware set-up, control software, and the latest developments for MX experiments. The experimental environment presents state-of-the-art instrumentation for high-throughput projects with a high-precision goniometer with an adaptable goniometer head, and a UV-light sample visualization system. Combined with an efficient automounting robot modified from the SSRL SAM system, a remote control system enables fully automated and remote-access X-ray diffraction experiments.

Lupus pernio with multiple bone cysts in the fingers

A 32-year-old Japanese man presented with a 3-year history of purple reddish, and painful swelling of his fingers along with indurated erythema on his nose and ears. He was diagnosed as having sarcoidosis 8 years prior because of uveitis and bilateral hilar lymphadenopathy. X-rays of the hands revealed multiple cystic lesions in the phalanges. Histological examination of the ear revealed epithelioid cell granulomas in the dermis. Oral prednisolone 20 mg/day improved his finger swelling and pain; however, his finger deformities and erythema remain unchanged. Bone involvement is sometimes seen in sarcoidosis and the hands are the most frequently affected areas. The frequency of bone involvement is higher in lupus pernio in comparison with other types of skin sarcoidosis. Systemic corticosteroids could be the first choice of treatment to relieve the symptoms.

Simulation Study on Geometric and Electronic Structure of Photovoltaic Molecules

We investigate the geometric and electronic structure of porphyrin-fullerene based supramolecular system in which have an extremely long-lived charge-separated state have been achieved, using first principle calculations. The results suggest that the LUMO state of this supramolecule is localized on the fullerene and HOMO state is localized on the porphyrin moiety.

X-ray phase imaging of biological soft tissue using a direct-sensing x-ray HARP tube camera

A HDTV camera having a direct-sensing x-ray high-gain avalanche rushing amorphous photoconductor (HARP) tube was used, for the first time, to acquire x-ray phase maps. The tube can achieve a high sensitivity as a result of the avalanche multiplication process in the HARP target. A beryllium plate, rather than a glass plate, was used as the face plate of the tube to minimize the loss of x-rays due to absorption, and a 15 microm thick HARP target was directly formed on it. In the experiment, the x-ray phase shifts produced by a rat liver were measured using synchrotron x-rays (lambda = 0.0766 nm) and a triple Laue-case (LLL) x-ray interferometer. Interference patterns produced by the sample were observed with the direct-sensing x-ray HARP tube camera. A voltage of 1300 V was applied to the HARP target to give an output signal gain of two. The camera was operated in 1125 scanning-line mode, and real-time images were stored on a workstation at a rate of 30 images/s with an image format of 960 (H) x 1100 (V) pixels. A phase-map image of the sample was successfully obtained using the fringe scanning method and phase unwrapping. The observed phase shifts ranged from 50 degrees to 200 degrees . Trees of blood vessels in the rat liver were clearly depicted without using a contrast agent. The spatial resolution of the x-ray camera was estimated to be better than 35 microm in the vertical direction and 100 microm in the horizontal direction.

Clinical pilot studies on pre-operative hyperthermic tumour ablation for advanced breast carcinoma using an 8 MHz radiofrequency heating device

The multimodality treatment approach for advanced breast cancer provides survival advantages with decreased locoregional and distant recurrences, but these intensive anti-tumour treatments cause severe myelosuppression. Thus, in this study, the usefulness of pre-operative anti-tumour treatment without myelosuppression was investigated. Nine patients with advanced breast carcinoma underwent pre-operative hyperthermic tumour ablation (HTA) using an 8 MHz radiofrequency (RF) heating device (Thermotron RF-8) combined with a grounded needle electrode. The patients had a mean age of 58.3+/-13.9 years and included four patients with stage IIIA, two with stage IIIB and three with stage IV cancer. The target temperature was over 50 degrees C. They tolerated pre-operative HTA therapy well with no early or late complications. The initial mean tumour size was 122.1+/-71.5 cm3 and the post-HTA tumour size was 82.2+/-63.4 cm3; the reduction rate was significant (p = 0.000 293). After the pre-operative HTA, all patients underwent surgery with Level III nodal extirpation. Post-operatively, no locoregional recurrence was observed. Microscopic examination of the primary focus showed complete coagulation necrosis expanding for a diameter of 3.5-5.0 cm. Taken together, the pre-operative HTA was a safe, well-tolerated and effective treatment, achieving tumour reduction as well as complete coagulation necrosis that resulted in a large volume of destruction in breast cancer tissue.

Systematic analysis of supersaturation and lysozyme crystal quality

A systematic study of the correlation between supersaturation and protein crystal quality was carried out employing atomic force microscopy (AFM) and X-ray crystallography with synchrotron radiation (SR). The surface morphology and growth rates of hen egg-white (HEW) lysozyme crystals soaked in various supersaturated solutions were first investigated by AFM. The results showed that the formation of two-dimensional islands increased as a function of supersaturation. The growth rate (molecule intake speed) also increased as a function of supersaturation. In order to examine the correlation between the surface morphology, growth rate and the crystal quality, X-ray diffraction experiments were performed. It was confirmed that crystals grown at lower supersaturations diffracted better with higher signal-to-noise ratios, including better agreement between symmetry-related reflections. The results strongly suggested that the molecular misorientation at high supersaturation affected the crystal quality.

Regulation of mammalian phospholipase D2: interaction with and stimulation by G(M2) activator

We have previously reported that a heat-stable activator for ganglioside metabolism, G(M2) activator, potently stimulates ADP-ribosylation factor (ARF)-dependent phospholipase D (PLD) activity (presumably PLD1) in an in vitro system [Nakamura, Akisue, Jinnai, Hitomi, Sarkar, Miwa, Okada, Yoshida, Kuroda, Kikkawa and Nishizuka (1998) Proc. Natl. Acad. Sci. U.S.A. 95, 12249-12253]. However, little is known about the regulation of PLD2. In the present studies we have investigated the regulation of PLD2 by G(M2) activator and various other regulators including ARF. PLD2 was potently stimulated in vitro by G(M2) activator in a time- and dose-dependent manner. Neither ARF nor protein kinase C caused any significant changes in PLD2 activity. Importantly, PLD2 responsiveness to ARF was greatly enhanced by G(M2) activator, suggesting a possible role for G(M2) activator as a coupling factor. G(M2) activator was also demonstrated to physically associate with PLD2 in a stoichiometric manner. Further, PMA stimulation of COS-7 cells overexpressing both G(M2) activator and PLD2 resulted in a marked increase in the association of the two molecules. Interestingly, ARF association with PLD2 was greatly increased by G(M2) activator. Moreover, G(M2) activator enhanced PMA-induced PLD activity in a synergistic manner with ARF in streptolysin-O-permeabilized, cytosol-depleted HL-60 cells, suggesting that G(M2) activator may regulate PLD in a concerted manner with other factors, including ARF, inside the cells.

Differential cellular targets of Epstein-Barr virus (EBV) infection between acute EBV-associated hemophagocytic lymphohistiocytosis and chronic active EBV infection

Unusual Epstein-Barr virus (EBV) infection into T or natural killer cells plays a pivotal role in the pathogenesis of acute EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and chronic active EBV infection (CAEBV). The precise frequency and localization of EBV genome in lymphocyte subpopulations especially within T-cell subpopulations are unclear in these EBV-related disorders. This study analyzed the frequency of EBV-infected cells in circulating lymphocyte subpopulations from 4 patients with acute EBV-HLH and 4 with CAEBV. EBV- encoded small RNA-1 in situ hybridization examination of peripheral blood lymphocytes showed a significantly higher frequency of EBV-infected cells of 1.0% to 13.4% in EBV-HLH and 1.6% to 25.6% in CAEBV, respectively. The patterns of EBV infection in lymphocyte subpopulations were quite different between acute EBV-HLH and CAEBV. EBV infection was predominant in CD8(+) T cells in all EBV-HLH patients, whereas the dominant EBV-infected cell populations were non-CD8(+) lymphocyte subpopulations in CAEBV patients. Phenotypical analysis revealed that EBV-infected cell populations from both EBV-HLH and CAEBV were activated. There was no predominance of any EBV substrain of latent membrane protein-1, EBV-associated nuclear antigen (EBNA)-1, and EBNA-2 genes between the 2 abnormal EBV-associated disorders, and self-limited acute infectious mononucleosis. These results showing differential virus-cell interactions between acute EBV-HLH and CAEBV indicated different pathogenic mechanisms against EBV infection between the 2 EBV-associated diseases, which accounts for the difference in clinical manifestations between the 2 diseases.

Crystallization and preliminary X-ray analysis of catalase-peroxidase from the halophilic archaeon Haloarcula marismortui

Catalase-peroxidases are bifunctional enzymes found in many microorganisms. Crystals of catalase-peroxidase from the halophilic archaeon Haloarcula marismortui were obtained using the hanging-drop vapour-diffusion method. The rhombic plate-shaped crystals were grown from purified protein solution using (NH(4))(2)SO(4) as precipitant at 293 K. The crystal belongs to the monoclinic system, space group C2, and diffracted beyond 2.0 A resolution.

Follicle-stimulating hormone promotes the growth of human epithelial ovarian cancer cells through the protein kinase C-mediated system

We have previously described that follicle-stimulating hormone (FSH) stimulated the growth of human epithelial ovarian cancer tissues and cells. In order to determine the signaling pathway on FSH action in ovarian cancer, we used an epithelial ovarian cancer cell line (HRA line) which constitutively FSH receptors (FSHRs). FSH significantly increased cell proliferation (230.1 +/- 20.5%, P < 0.05) and (3)H-thymidine uptake (443.5 +/- 35.1%, P < 0.01). 1-(5-Isoquinolinesulfonyl)-2-methyipiperazine (H7, 1 5 nM), staurosponine (STR, 5 nM) and calphostin C (5 nM), specific protein kinase C (PKC) inhibitors, significantly suppressed the FSH-stimulated cell growth (120.2-140.2%, P < 0.05) and (3)H-thymidine uptake (140.5-173.9%, P < 0.05), whereas N-(2-guanidinoethyl)-5-isoquinoline-sulfon-amide (HA1004, l5 nM), which is a derivant of H7 and inhibits most of protein kinases except PKC, showed no effect on the FSH-stimulated cell growth and (3)H-thymidine uptake. A pretreatment with 12-0-tetradecanoylphorbol-13 acetate (TPA, 100 ng/ml) or STR (20 nM) significantly suppressed the subsequent FSH-stimulated cell growth (TPA; 152.3 +/-10.3%, STR; 160.4 +/- 15.9%, P < 0.05) and (3)H-thymidine uptake (TPA; 250.4 +/-18.3%, STR; 208.7 +/- 15.9%, P < 0.05). STR abolished the suppression of TPA preincubation on the subsequent FSH-stimulated cell growth and (3)H-thymidine uptake. HRA cells constitutively expressed PKCalpha but not PKCbeta nor PKCgamma. The levels of either expression of PKCalpha protein and mRNA were significantly amplified by FSH. These data suggest that stimulation of PKCalpha transcription is involved in the FSH-stimulated cell growth and DNA synthesis in epithelial ovarian cancer cells.

Horizontal transfer of the photosynthesis gene cluster and operon rearrangement in purple bacteria

A 37-kb photosynthesis gene cluster was sequenced in a photosynthetic bacterium belonging to the beta subclass of purple bacteria (Proteobacteria), Rubrivivax gelatinosus. The cluster contained 12 bacteriochlorophyll biosynthesis genes (bch), 7 carotenoid biosynthesis genes (crt), structural genes for photosynthetic apparatuses (puf and puh), and some other related genes. The gene arrangement was markedly different from those of other purple photosynthetic bacteria, while two superoperonal structures, crtEF-bchCXYZ-puf and bchFNBHLM-lhaA-puhA, were conserved. Molecular phylogenetic analyses of these photosynthesis genes showed that the photosynthesis gene cluster of Rvi. gelatinosus was originated from those of the species belonging to the alpha subclass of purple bacteria. It was concluded that a horizontal transfer of the photosynthesis gene cluster from an ancestral species belonging to the alpha subclass to that of the beta subclass of purple bacteria had occurred and was followed by rearrangements of the operons in this cluster.

Laparoscopic wedge resection of gastric submucosal tumors

Minimally invasive surgery has revolutionized the treatment of gastrointestinal tumors. Submucosal tumors (SMTs) of the stomach can be resected using laparoscopic techniques. Between 1993 and 1997, laparoscopic wedge resection was performed in 34 patients with an SMT of the stomach. The tumors ranged from 8 to 60 mm in diameter. All surgical margins were clear. The average operative time was 131 minutes. Most of the patients began eating on the first postoperative day and were discharged within 5 to 7 days. Histopathologic examination of the tumors showed gastrointestinal stromal tumor (n = 14), ectopic pancreas (n = 7), leiomyosarcoma (n = 4), schwannoma (n = 3), carcinoid (n = 2), leiomyoma (n = 2), an inflammatory lesion caused by parasites (n = 1), and cyst (n = 1). No recurrences were observed over the 5-year follow-up period. A solid SMT of the stomach larger than 20 mm in diameter can be treated using laparoscopic wedge resection.

Enhancement in the perfection of orthorhombic lysozyme crystals grown in a high magnetic field (10 T)

Orthorhombic crystals of hen egg-white (HEW) lysozyme were grown in a homogeneous and static magnetic field of 10 T. All crystals grown at 10 T were oriented such that their crystallographic c axes were parallel to the magnetic field direction and showed a narrower average full-width at half-maximum (FWHM) of the rocking curve than those grown at 0 T. Rocking-width measurements were made at the BL-10A station at the Photon Factory, Tsukuba, Japan, using a high-resolution vertical-type four-circle diffractometer. Crystal perfection was evaluated using the FWHM of the rocking curve; the effects of the magnetic field on the quality of the crystals were examined by comparison of the FWHM of seven crystals grown at 10 and 0 T. The FWHMs of the reflections along the a, b and c axes decreased by 23.5, 35.3 and 27.8%, respectively, and those of other general reflections decreased by 17.4-42.2% in the crystals grown at high magnetic field. These results clearly showed that a magnetic field of 10 T improved the crystal perfection of the orthorhombic lysozyme crystals. As a result, the maximum resolution of X-ray diffraction increased from 1.3 A at 0 T to 1.13 A at 10 T. The magnetic field also affected the dimensions of the unit cell, increments being 0.2% for the a and c axes and 0.1% for the b axis, respectively. These facts suggest that the application of a high magnetic field during crystallization might result in remarkable enhancements in the diffraction power of protein crystals having magnetic anisotropy.

Head movements and neck muscle activities associated with the jaw movement during mastication in the rabbit authors

Rhythmical head movements and neck muscle activities associated with the masticatory jaw movement were investigated in rabbits. In natural mastication, head movements and neck muscle activities showed a rhythmical feature synchronized with jaw movement. During cortically induced rhythmical jaw movements, some neck muscle showed rhythmical activity induced by biting a wooden stick. Neck muscles may contribute to the rhythmical head movement after loading the tooth with food.

Matrix metalloproteinase expression in cultured human gastric wall fibroblasts--interactions with Helicobacter pylori isolated from patients with ulcers

BACKGROUND

Matrix metalloproteinases (MMPs), enzymes capable of degrading collagens and other extracellular matrix components, have been implicated in gastric ulcer formation. However, the effect on MMP expression of Helicobacter pylori, also implicated in these lesions, has not been studied to our knowledge.

AIM

To seek links between H. pylori and MMP expression likely to affect gastric ulcer formation. After fibroblasts from human gastric wall were cocultured with H. pylori. concentrations of MMP-1 and -2 in the medium were determined by enzyme-linked immunosorbent assays.

RESULTS

Whereas MMP-1 was not detected in media from fibroblasts or H. pylori culture alone, MMP-1 was detected in cocultures (P<0.01). Similar amounts of MMP-2 were detected in medium from fibroblasts cultured alone and with H. pylori. No MMP-2 production by H. pylori cultured alone was detected.

CONCLUSIONS

MMP-1 appears to be important in gastric ulcer pathogenesis, and MMP-1 induction by H. pylori may impede gastric ulcer healing.

Activation of matrix metalloproteinase-2 in head and neck squamous cell carcinoma: studies of clinical samples and in vitro cell lines co-cultured with fibroblasts

We undertook this present study to investigate the activation of matrix metalloproteinase-2 (MMP-2) in human head and neck squamous cell carcinomas (HNSCC) tissues and cell lines. Gelatinolytic activities of active MMP-2 were significantly higher in carcinoma samples than in normal portions. Furthermore, the activation ratio of proMMP-2 significantly correlated with cervical lymph node metastasis. In vitro studies revealed an HNSCC cell line, HEp-2, to produce neither the pro form nor the active form of MMP-2, but human fibroblasts were found to produce proMMP-2. However, coculture of HEp-2 cells with fibroblasts resulted in the production of not only proMMP-2 but also activeMMP-2 in the culture medium. Northern blot analysis revealed a stronger expression of membrane-type 1 matrix metalloproteinase (MT1-MMP),which is a specific activator of MMP-2, mRNA in HEp-2 cells than in fibroblasts. These results suggest the activation of proMMP-2 as an important event in the process of HNSCC metastasis. They also suggest MMP-2 is secreted in its pro form by stromal fibroblasts surrounding the cancer cells and activated by MT1-MMP localized on the cancer cells.

Laparoscopic wedge resection of gastric submucosal tumors

Minimally invasive surgery has revolutionized the treatment of gastrointestinal tumors. Submucosal tumors (SMTs) of the stomach can be resected using laparoscopic techniques. Between 1993 and 1997, laparoscopic wedge resection was performed in 34 patients with an SMT of the stomach. The tumors ranged from 8 to 60 mm in diameter. All surgical margins were clear. The average operative time was 131 minutes. Most of the patients began eating on the first postoperative day and were discharged within 5 to 7 days. Histopathologic examination of the tumors showed gastrointestinal stromal tumor (n = 14), ectopic pancreas (n = 7), leiomyosarcoma (n = 4), schwannoma (n = 3), carcinoid (n = 2), leiomyoma (n = 2), an inflammatory lesion caused by parasites (n = 1), and cyst (n = 1). No recurrences were observed over the 5-year follow-up period. A solid SMT of the stomach larger than 20 mm in diameter can be treated using laparoscopic wedge resection.

Predictive value of Ki-67, p53 protein, and DNA content in the diagnosis of gastric carcinoma

BACKGROUND

The ability to make a precise preoperative diagnosis is a valuable and effective method in improving the prognosis of patients with gastric carcinoma. The authors examined retrospectively whether preoperative histopathologic analysis with p53 protein, Ki-67 labeling index, and DNA ploidy along with preoperative radiographic and endoscopic findings led to a precise preoperative diagnosis of patients with gastric carcinoma.

METHODS

Histopathologic analysis of p53 protein, Ki-67 labeling index, and DNA content was performed on formalin fixed, paraffin embedded tissue. Tissue sections from endoscopic and surgically resected specimens were stained immunohistochemically for p53 protein and Ki-67 labeling index, and the cell nuclear DNA content of the surgically resected primary lesion was measured using a microspectrophotometer. These analyses were performed on 16 patients with early gastric carcinoma (EGC) who were diagnosed with advanced gastric carcinoma (AGC) based on the preoperative imaging findings and on 15 patients with AGC who were diagnosed preoperatively with EGC.

RESULTS

Overexpression of p53 in the AGC group was significantly more frequent compared with that in the EGC group (P = 0.0386). With regard to the correlation between lymph node metastases and p53 overexpression, there was no apparent relation in either the AGC group (P = 0.648) or the EGC group (P = 0.726). The AGC group had significantly higher Ki-67 labeling indices compared with the EGC group (P = 0.0195). There was complete concordance between endoscopic and surgically resected specimens with regard to the p53 and Ki-67 labeling index findings. DNA ploidy in the primary tumor did not differ between the AGC and EGC groups. The survival rates for the EGC group were significantly superior to those for the AGC group (P = 0.0312).

CONCLUSIONS

The findings of the current study suggest that in routine clinical practice, the combination of preoperative imaging findings in addition to Ki-67 labeling indexes, and p53 protein analyses may be useful for the accurate diagnosis of EGC; however, DNA ploidy did not appear to reflect the growth potential of gastric carcinoma.

Predictive value of Ki-67, p53 protein, and DNA content in the diagnosis of gastric carcinoma

BACKGROUND

The ability to make a precise preoperative diagnosis is a valuable and effective method in improving the prognosis of patients with gastric carcinoma. The authors examined retrospectively whether preoperative histopathologic analysis with p53 protein, Ki-67 labeling index, and DNA ploidy along with preoperative radiographic and endoscopic findings led to a precise preoperative diagnosis of patients with gastric carcinoma.

METHODS

Histopathologic analysis of p53 protein, Ki-67 labeling index, and DNA content was performed on formalin fixed, paraffin embedded tissue. Tissue sections from endoscopic and surgically resected specimens were stained immunohistochemically for p53 protein and Ki-67 labeling index, and the cell nuclear DNA content of the surgically resected primary lesion was measured using a microspectrophotometer. These analyses were performed on 16 patients with early gastric carcinoma (EGC) who were diagnosed with advanced gastric carcinoma (AGC) based on the preoperative imaging findings and on 15 patients with AGC who were diagnosed preoperatively with EGC.

RESULTS

Overexpression of p53 in the AGC group was significantly more frequent compared with that in the EGC group (P = 0.0386). With regard to the correlation between lymph node metastases and p53 overexpression, there was no apparent relation in either the AGC group (P = 0.648) or the EGC group (P = 0.726). The AGC group had significantly higher Ki-67 labeling indices compared with the EGC group (P = 0.0195). There was complete concordance between endoscopic and surgically resected specimens with regard to the p53 and Ki-67 labeling index findings. DNA ploidy in the primary tumor did not differ between the AGC and EGC groups. The survival rates for the EGC group were significantly superior to those for the AGC group (P = 0.0312).

CONCLUSIONS

The findings of the current study suggest that in routine clinical practice, the combination of preoperative imaging findings in addition to Ki-67 labeling indexes, and p53 protein analyses may be useful for the accurate diagnosis of EGC; however, DNA ploidy did not appear to reflect the growth potential of gastric carcinoma.

Predictive value of Ki-67, p53 protein, and DNA content in the diagnosis of gastric carcinoma

BACKGROUND

The ability to make a precise preoperative diagnosis is a valuable and effective method in improving the prognosis of patients with gastric carcinoma. The authors examined retrospectively whether preoperative histopathologic analysis with p53 protein, Ki-67 labeling index, and DNA ploidy along with preoperative radiographic and endoscopic findings led to a precise preoperative diagnosis of patients with gastric carcinoma.

METHODS

Histopathologic analysis of p53 protein, Ki-67 labeling index, and DNA content was performed on formalin fixed, paraffin embedded tissue. Tissue sections from endoscopic and surgically resected specimens were stained immunohistochemically for p53 protein and Ki-67 labeling index, and the cell nuclear DNA content of the surgically resected primary lesion was measured using a microspectrophotometer. These analyses were performed on 16 patients with early gastric carcinoma (EGC) who were diagnosed with advanced gastric carcinoma (AGC) based on the preoperative imaging findings and on 15 patients with AGC who were diagnosed preoperatively with EGC.

RESULTS

Overexpression of p53 in the AGC group was significantly more frequent compared with that in the EGC group (P = 0.0386). With regard to the correlation between lymph node metastases and p53 overexpression, there was no apparent relation in either the AGC group (P = 0.648) or the EGC group (P = 0.726). The AGC group had significantly higher Ki-67 labeling indices compared with the EGC group (P = 0.0195). There was complete concordance between endoscopic and surgically resected specimens with regard to the p53 and Ki-67 labeling index findings. DNA ploidy in the primary tumor did not differ between the AGC and EGC groups. The survival rates for the EGC group were significantly superior to those for the AGC group (P = 0.0312).

CONCLUSIONS

The findings of the current study suggest that in routine clinical practice, the combination of preoperative imaging findings in addition to Ki-67 labeling indexes, and p53 protein analyses may be useful for the accurate diagnosis of EGC; however, DNA ploidy did not appear to reflect the growth potential of gastric carcinoma.