A novel index combining fecal immunochemical test, DNA test, and age improves detection of advanced colorectal adenoma

Although the fecal immunochemical test for hemoglobin (FIT) is a widely used screening test for colorectal cancer, it is not sensitive enough to detect advanced colorectal adenoma. To address this issue, we performed this study to investigate whether combining the FIT and fecal DNA testing of methylated somatostatin (SST) could improve diagnostic performance for advanced colorectal adenoma. We collected feces from 79 healthy subjects with negative results on colonoscopy, 43 patients with non-advanced colorectal adenoma, 117 patients with advanced colorectal adenoma, and 126 patients with colorectal cancer. After fecal DNA was incubated with methylation-sensitive restriction enzymes, SST methylation levels were measured by droplet digital PCR. Using logistic multivariate analysis, we established a prediction formula for detecting colorectal neoplasia and named it the FAMS (FIT, age, methylated SST) index. The diagnostic performance of a single use of FIT for advanced colorectal adenoma showed a sensitivity of 29.1% (34/117) and specificity of 89.3% (109/122). In contrast, the FAMS index showed a sensitivity of 56.4% (66/117) at a similar specificity point of 91.0% (111/122). Furthermore, even at the higher specificity point of 94.3% (115/122), the sensitivity was still higher than that of FIT, reaching 42.7% (50/117). As the FAMS index showed better diagnostic performance for advanced colorectal adenoma than a single use of FIT, the FAMS index could be a promising tool for detecting advanced colorectal adenoma.

Incidence and risk factors for perineal hernia after robotic abdominoperineal resection: a single-center, retrospective cohort study

BACKGROUND

Perineal hernia (PH) is a late complication of abdominoperineal resection (APR) that may compromise a patient's quality of life. The frequency and risk factors for PH after robotic APR adopting recent rectal cancer treatment strategies remain unclear.

METHODS

Patients who underwent robotic APR for rectal cancer between December 2011 and June 2022 were retrospectively examined. From July 2020, pelvic reinforcement procedures, such as robotic closure of the pelvic peritoneum and levator ani muscles, were performed as prophylactic procedures for PH whenever feasible. PH was diagnosed in patients with or without symptoms using computed tomography 1 year after surgery. We examined the frequency of PH, compared characteristics between patients with PH (PH+) and without PH (PH-), and identified risk factors for PH.

RESULTS

We evaluated 142 patients, including 53 PH+ (37.3%) and 89 PH- (62.6%). PH+ had a significantly higher rate of preoperative chemoradiotherapy (26.4% versus 10.1%, p = 0.017) and a significantly lower rate of undergoing pelvic reinforcement procedures (1.9% versus 14.0%, p = 0.017). PH+ had a lower rate of lateral lymph node dissection (47.2% versus 61.8%, p = 0.115) and a shorter operative time (340 min versus 394 min, p = 0.110). According to multivariate analysis, the independent risk factors for PH were preoperative chemoradiotherapy, not undergoing lateral lymph node dissection, and not undergoing a pelvic reinforcement procedure.

CONCLUSIONS

PH after robotic APR for rectal cancer is not a rare complication under the recent treatment strategies for rectal cancer, and performing prophylactic procedures for PH should be considered.

Efficacy of laparoscopic surgery for loop colostomy: a propensity-score-matched analysis

PURPOSE

Colostomy is a common procedure for fecal diversion, but the optimal colostomy approach is unclear in terms of surgical outcomes and stoma-related complications. The purpose of this study was to examine the efficacy and feasibility of laparoscopic loop colostomy.

METHODS

This retrospective cohort study included patients who underwent loop colostomy at Shizuoka Cancer Center in Japan between April 2010 and March 2022. Patients were divided into two groups based on surgical approach: the laparoscopic (LAP) and open (OPEN) groups. Surgical outcomes and the incidences of stoma-related complications such as stomal prolapse (SP), parastomal hernia (PSH), and skin disorders (SD) were compared with and without propensity score matching.

RESULTS

Of the 388 eligible patients, 180 (46%) were in the LAP group and 208 (54%) were in the OPEN group. The male-to-female ratio was 5.5:4.5 in the Lap group and was 5.3:4.7 in the OPEN group, respectively. The median age was 68 years (range, 31-88 years) in the LAP group and 65 years (range, 23-93 years) in the OPEN group, respectively. The LAP group, compared with the OPEN group, had a shorter operative time and lower incidences of surgical site infection (3.9% versus 16.3%, respectively; p < 0.01) and SD (11.7% versus 24.5%, respectively; p < 0.01). There was no significant difference between the LAP and OPEN groups in the incidence of SP (17.3% versus 17.3%, respectively) or PSH (8.9% versus 6.7%, respectively). After propensity score matching, the incidences of surgical site infection and SD were significantly lower in the LAP group than in the OPEN group, while there were no significant differences in the operative time or the incidences of SP and PSH.

CONCLUSION

Our results suggest that laparoscopic surgery could be beneficial and feasible in loop colostomy.

Health care transition for cerebral palsy with intellectual disabilities: A systematic review

OBJECTIVE

Today, most individuals with cerebral palsy are adults who need a paediatric-to-adult health care transition. However, many remain in paediatric care for treatment of adult-onset health issues. Therefore, a systematic review based on the 'Triple Aim' framework was performed to determine the status of paediatric-to-adult health care transition for people with cerebral palsy. A comprehensive evaluation of transitional care was proposed for using this framework. It consists of 'experience of care', meaning satisfaction with the care, 'population health', meaning the well-being of patients, and 'cost', meaning cost-effectiveness.

METHOD

Electronic database (PubMed) searches were performed. The inclusion criteria were original articles published between 1990 and 2020. The search terms used in this study were ('cerebral palsy' AND 'transition to adult health care') OR ('cerebral palsy' AND 'transition'). The study type had to be epidemiological, case report, case-control, and cross-sectional, but not qualitative. The outcomes of the studies were categorised into 'care experience', 'population health', and 'cost', according to the Triple Aim framework.

RESULTS

Thirteen articles met the abovementioned inclusion criteria. Few studies have examined the effect of the intervention of transition for young adults with cerebral palsy. Participants in some studies had no intellectual disability. Young adults were dissatisfied with the 'care experience', 'population health', and 'cost' and had unmet health needs and inadequate social participation.

INTERPRETATION

Further transition intervention studies with a comprehensive assessment and proactive involvement of individuals are warranted. The presence of an intellectual disability should be considered.

Comparison of two primer-probe sets of Fusobacterium nucleatum using droplet digital polymerase chain reaction for the detection of colorectal neoplasia from faecal samples

BACKGROUND

Although faecal DNA testing of Fusobacterium nucleatum (Fn) is expected to be useful for colorectal neoplasia detection, there is no standardized quantification method of Fn. We performed this study to establish a possible standardized method.

METHODS

In this study, 322 participants including 71 subjects without colorectal neoplasia (control group), 31 patients with non-advanced colorectal adenoma, 93 patients with advanced colorectal adenoma, and 127 patients with colorectal cancer were enrolled. Faecal Fn were quantified by droplet digital PCR (ddPCR) using two PCR primer-probe sets reported previously that are tentatively named Fn1 and Fn2. Fn1 has been used in ddPCR by us and Fn2 has been widely used in quantitative real-time PCR.

RESULTS

The Fn copy number using Fn1 was five times higher than that using Fn2, with a linear relationship shown between them. Receiver operating characteristic curve analysis showed the area under the curve (AUC) to be almost the same between Fn1 and Fn2 in discriminating between the control group and the colorectal cancer group (AUC = 0.81 and 0.81, respectively), and between the control/non-advanced colorectal adenoma group and the advanced colorectal adenoma/colorectal cancer group (AUC = 0.74 and 0.74, respectively).

CONCLUSIONS

As the diagnostic performance was quite similar between Fn1 and Fn2, ddPCR-based Fn testing using Fn1 and Fn2 could be a possible standardized method for a colorectal neoplasia screening test, considering that Fn levels quantified by Fn1 are about five times higher than those by Fn2.

Detailed Arterial Anatomy and Its Anastomoses of the Sphenoid Ridge and Olfactory Groove Meningiomas with Special Reference to the Recurrent Branches from the Ophthalmic Artery

BACKGROUND AND PURPOSE

Detailed arterial anatomy of the sphenoid ridge and olfactory groove meningiomas is complicated due to the fine angioarchitecture and anastomoses between each feeder. Herein, we present details of the arterial anatomy and the relationships of feeders in these lesions.

MATERIALS AND METHODS

This study included 20 patients admitted to our department between April 2015 and March 2020. Conditions of subjects consisted of 16 sphenoid ridge meningiomas and 4 olfactory groove meningiomas. We mainly analyzed arterial anatomy using 3D rotational angiography and slab MIP images of these lesions. We also analyzed the anastomoses of each feeder.

RESULTS

We found that 19 (95%), 15 (75%), and 15 (75%) lesions had feeders from the ophthalmic, internal carotid, and external carotid arteries, respectively. As feeders from the ophthalmic artery, recurrent meningeal arteries were involved in 18 lesions (90%). Fifteen lesions (75%) had anastomoses between each feeder.

CONCLUSIONS

Most of the meningiomas in the sphenoid ridge and olfactory groove had feeders from the ophthalmic and internal carotid arteries. There were various anastomoses between each feeder. This is the first report to demonstrate the detailed arterial anatomy and frequency of recurrent branches from the ophthalmic artery and their anastomoses using detailed imaging techniques.

Which is more important in the management of splenic flexure colon cancer: strict central lymph node dissection or adequate bowel resection margin?

BACKGROUND

What qualifies as optimal lymph node (LN) dissection in the surgical management of splenic flexure colon cancer (SFCC) still remains controversial because few studies have evaluated the distribution of LN metastasis of SFCC. The aim of this study was to clarify detailed distribution of LN metastasis and long-term outcomes of SFCC.

METHODS

This retrospective study enrolled patients who had curative colectomy for primary transverse or descending colon cancer of pathological stage I, II, or III at a single high-volume cancer center between April 2002 and December 2018. The 538 eligible patients were divided into three groups: patients with SFCC (SFCC group, n = 168), patients with proximal transverse colon cancer (PTCC group, n = 290), and patients with distal descending colon cancer (DDCC group, n = 80). LNs were classified into horizontal (pericolic) and vertical (intermediate and main) nodes. Intermediate and main LN station numbers were defined according to the Japanese Society for Cancer of the Colon and Rectum classification. Distributions of LN metastasis and long-term outcomes were compared.

RESULTS

In the SFCC group, the mean age was 67.3 ± 10.5 years and 110 patients (65.5%) were male. The proportion of patients with LN metastasis in the intermediate or main region was significantly lower in the SFCC group (8%) than in the PTCC (37%) (p < 0.01) or DDCC group (29%) (p < 0.01) in pathological stage III patients. In the SFCC group, the incidence of pericolic LN metastasis on the oral side of tumor (43%) was significantly higher than in the PTCC group (21%) (p < 0.01) and was similar to that in the DDCC group (42%) (p = 0.51), while in the SFCC group, the incidence of pericolic LN metastasis on the anal side of tumor (17%) was lower than in the PTCC group (31%) and was also similar to that in the DDCC group (21%). There were no significant differences in disease-specific survival rates among all groups.

CONCLUSIONS

LN metastasis occurred mainly in the pericolic region, especially on the oral side of the tumor in SFCC. It may, therefore, be important to have an adequate bowel resection margin, especially on the oral side, for SFCC.

Objective Assessment of the Utility of Chromoendoscopy with a Support Vector Machine

Purpose

The utility of chromoendoscopy for early gastric cancer (GC) was determined by machine learning using data of color differences.

Methods

Eighteen histopathologically confirmed early GC lesions were examined. We prepared images from white light endoscopy (WL), indigo carmine (Indigo), and acetic acid-indigo carmine chromoendoscopy (AIM). A border between cancerous and non-cancerous areas on endoscopic images was established from post-treatment pathological findings, and 2000 pixels with equivalent luminance values were randomly extracted from each image of cancerous and non-cancerous areas. Each pixel was represented as a three-dimensional vector with RGB values and defined as a sample. We evaluated the Mahalanobis distance using RGB values, indicative of color differences between cancerous and non-cancerous areas. We then conducted diagnosis test using a support vector machine (SVM) for each image. SVM was trained using the 100 training samples per class and determined which area each of 1900 test samples per class came from.

Results

The means of the Mahalanobis distances for WL, Indigo, and AIM were 1.52, 1.32, and 2.53, respectively and there were no significant differences in the three modalities. Diagnosability per endoscopy technique was assessed using the F1 measure. The means of F1 measures for WL, Indigo, and AIM were 0.636, 0.618, and 0.687, respectively. AIM images were better than WL and Indigo images for the diagnosis of GC.

Conclusion

Objective assessment by SVM found AIM to be suitable for diagnosis of early GC based on color differences.

Fusobacterium nucleatum as a prognostic marker of colorectal cancer in a Japanese population

BACKGROUND

Accumulating evidence shows an overabundance of Fusobacterium nucleatum in colorectal tumor tissues. However, the correlation between the absolute copy number of F. nucleatum in colorectal cancer tissues and colorectal cancer progression is unclear from previous reports. Therefore, we performed a study to compare the abundance of F. nucleatum in colorectal tissues with clinicopathologic and molecular features of colorectal cancer.

METHODS

We collected 100 colorectal cancer tissues and 72 matched normal-appearing mucosal tissues. Absolute copy numbers of F. nucleatum were measured by droplet digital PCR.

RESULTS

The detection rates of F. nucleatum were 63.9% (46/72) in normal-appearing mucosal tissues and 75.0% (75/100) in CRC tissue samples. The median copy number of F. nucleatum was 0.4/ng DNA in the normal-appearing colorectal mucosa in patients with colorectal cancer and 1.9/ng DNA in the colorectal cancer tissues (P = 0.0031). F. nucleatum copy numbers in stage IV colorectal cancer tissues were significantly higher than those in the normal-appearing mucosa in patients with colorectal cancer (P = 0.0016). The abundance of F. nucleatum in colorectal cancer tissues correlated with tumor size and KRAS mutation and was significantly associated with shorter overall survival times; this trend was notable in the patients with stage IV colorectal cancer. Focusing on normal-appearing mucosa in the patients with colorectal cancer, the F. nucleatum copy number was significantly higher in the patients with stage IV rather than stages I-III.

CONCLUSION

These results suggest that determining F. nucleatum levels may help predict clinical outcomes in colorectal cancer patients. Further confirmatory studies using independent datasets are required to confirm our findings.

Robotic-assisted multivisceral resection for rectal cancer: short-term outcomes at a single center

BACKGROUND

The safety and feasibility of robotic-assisted multivisceral resection for locally advanced rectal cancer remain unclear. The aim of this study was to assess the short-term outcomes of this procedure at our institution.

METHODS

From December 2011 to December 2016, patients who underwent robotic-assisted multivisceral resection for rectal cancer were investigated. Patient demographics, treatment characteristics, perioperative outcomes, and pathological results were evaluated retrospectively.

RESULTS

There were 31 patients; 17 men (54.8%) and 14 women (45.2%), with a median age of 65 years (range 40-82 years). Twenty-one patients (67.7%) had a cT4 tumor, 9 patients (29.0%) had a pT4b tumor, and all patients except one (96.8%) underwent complete resection of the primary tumor with negative resection margins. Eleven patients (35.5%) received neoadjuvant chemoradiation. The most commonly resected organ was the vaginal wall (n = 12, 38.7%), followed by the prostate (n = 10, 32.3%). Lateral lymph node dissection was performed in 20 patients (64.5%). The median operative time was 394 min (range 189-549 min), and the median blood loss was 41 mL (range 0-502 mL). None of the patients received intraoperative blood transfusions or required conversion to open. Overall, postoperative complications occurred in 11 patients (35.5%). The most frequent complication was urinary retention (n = 5, 16.1%), and none of the patients developed serious complications classified as Clavien-Dindo grades III-V.

CONCLUSIONS

Robotic-assisted multivisceral resection for rectal cancer is safe and technically feasible.

Highly sensitive fluorescence detection of metastatic lymph nodes of gastric cancer with photo-oxidation of protoporphyrin IX

BACKGROUND

The establishment of a precise and rapid method to detect metastatic lymph nodes (LNs) is essential to perform less invasive surgery with reduced gastrectomy along with reduced lymph node dissection. We herein describe a novel imaging strategy to detect 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence in excised LNs specifically with reduced effects of tissue autofluorescence based on photo-oxidation of PpIX. We applied the method in a clinical setting, and evaluated its feasibility.

METHODS

To reduce the unfavorable effect of autofluorescence, we focused on photo-oxidation of PpIX: Following light irradiation, PpIX changes into another substance, photo-protoporphyrin, via an oxidative process, which has a different spectral peak, at 675 nm, whereas PpIX has its spectral peak at 635 nm. Based on the unique spectral alteration, fluorescence spectral imaging before and after light irradiation and subsequent originally-developed image processing was performed. Following in vitro study, we applied this method to a total of 662 excised LNs obtained from 30 gastric cancer patients administered 5-ALA preoperatively.

RESULTS

Specific visualization of PpIX was achieved in in vitro study. The method allowed highly sensitive detection of metastatic LNs, with sensitivity of 91.9% and specificity of 90.8% in the in vivo clinical trial. Receiver operating characteristic analysis indicated high diagnostic accuracy, with the area under the curve of 0.926.

CONCLUSIONS

We established a highly sensitive and specific 5-ALA-induced fluorescence imaging method applicable in clinical settings. The novel method has a potential to become a useful tool for intraoperative rapid diagnosis of LN metastasis.

[Case with gradually enlarging lymphoepithelial cyst of the pancreas that necessitated enucleation]

A 54-year-old man exhibited a pancreatic mass on abdominal ultrasonography. Diagnostic imaging with endoscopic ultrasonography, computed tomography, and magnetic resonance imaging revealed that the mass comprised various internal structures and was not connected to the pancreatic duct. Over a period of 4 years and 2 months, the mass increased from 22mm to 32mm in diameter. Laparoscopic enucleation was performed, and a histopathological diagnosis of a lymphoepithelial cyst (LEC) of the pancreas was obtained. LEC is rare and seldom reported in the literature. Although it is considered to be benign, most case reports indicate that they tend to increase in size. This indicates that LEC should be carefully monitored if surgery is not performed after diagnosis.

[Is the incidence of postoperative pulmonary thromboembolism in Japan lower than that in the western countries?]

BACKGROUND

The Japanese Society of Anesthesiologists (JSA) has investigated the incidence of postoperative pulmonary thromboembolism (PTE) for several years.

METHODS

According to the JSA project, we surveyed the annual incidence of postoperative PTE in Kanazawa Medical University Hospital in 2008.

RESULTS

PTE was diagnosed radiographically in 6 out of 2339 patients, who were > or =15 years of age and had undergone surgical procedures under general anesthesia. The incidence was 0.257% and approximately tenfold that reported by the JSA. All the patients were subjected to lower extremity surgery. Two patients went into shock after they had first walked postoperatively. Symptoms of the other four patients were nonspecific but surgeons in charge suspected PTE.

CONCLUSIONS

Our data suggest that the actual incidence of postoperative PTE in Japan may be far greater than that reported by the JSA.

Helicobacter pylori typing as a tool for tracking human migration

Helicobacter pylori strains from different geographic areas exhibit clear phylogeographical differentiation; therefore, the genotypes of H. pylori strains can serve as markers for the migration of human populations. Currently, the genotypes of two virulence factors of H. pylori, cagA and vacA, and multilocus sequence typing (MLST) are widely used markers for genomic diversity within H. pylori populations. There are two types of cagA: the East Asian type and the Western type. In addition, the right end of the cag pathogenicity island is divided into five subtypes and there are distinct mosaic structures at the signal region and the middle region of vacA. Using combinations of the cagA, cag right end junction, and vacA genotypes, five major groups (East Asia type, South/Central Asia type, Iberian/Africa type and Europe type) have been defined according to geographical associations. MLST has revealed seven modern population types and six ancestral population types of H. pylori, and is a useful tool for mapping human migration patterns. Serial studies of large numbers of H. pylori strains, including strains isolated from aboriginal populations, show that MLST analysis provides more detailed information on human migration than does the analysis of human genetics. H. pylori infection is rapidly declining as a result of improvements in personal hygiene and quality of life. The molecular epidemiology of H. pylori infection has much to tell us and should be studied before it disappears entirely.

The association of vacA genotype and Helicobacter pylori-related disease in Latin American and African populations

In the populations of Western countries, particular genotypes of the vacuolating cytotoxin gene, vacA (vacA s, signal region variants; vacA m, middle region variants) of Helicobacter pylori are believed to be risk factors for the development of peptic ulcers and gastric cancer. However, it was unclear whether these vacA gene variants are associated with the development of gastrointestinal diseases in developing nations. The relationship between vacA genotypes and H. pylori-related disease development in Latin American and African populations was investigated using meta-analysis of 2612 patients from Latin America (2285 strains) and 520 patients from Africa (434 strains). The frequencies of vacA s and m genotypes differed between strains from Latin America (77.2% for s1 and 68.1% for m1) and Africa (83.9% for s1 and 56.7% for m1). Latin American strains with s1 and m1 genotypes increased the risk of gastric cancer (OR 4.17, 95% CI 2.49-6.98 for s1, and 3.59, 2.27-5.68 for m1) and peptic ulcers (e.g. 1.73, 1.37-2.20 for s1). African strains with the s1 or m1 genotypes also increased the risk of peptic ulcers (8.69, 1.16-64.75 for s1) and gastric cancer (10.18, 2.36-43.84 for m1). The cagA-positive genotype frequently coincided with s1 and m1 genotypes in both populations. Overall, the vacA s and m genotypes were related to gastric cancer and peptic ulcer development and might be useful markers of risk factors for gastrointestinal disease, especially in Latin America. Further studies will be required to evaluate the effects of vacA genotypes in African populations because of the small sample number currently available.

Neuroprotection by propargylamines in Parkinson's disease: intracellular mechanism underlying the anti-apoptotic function and search for clinical markers

In Parkinson's and other neurodegenerative diseases, a therapeutic strategy has been proposed to halt progressive cell death. Propargylamine derivatives, rasagiline and (-)deprenyl (selegiline), have been confirmed to protect neurons against cell death induced by various insults in cellular and animal models of neurodegenerative disorders. In this paper, the mechanism and the markers of the neuroprotection are reviewed. Propargylamines prevent the mitochondrial permeabilization, membrane potential decline, cytochrome c release, caspase activation and nuclear translocation of glyceraldehyde 3-phosphate dehydrogenase. At the same time, rasagiline induces anti-apoptotic pro-survival proteins, Bcl-2 and glial cell-line derived neurotrophic factor, which is mediated by activated ERK-NF-kappaB signal pathway. DNA array studies indicate that rasagiline increases the expression of the genes coding mitochondrial energy synthesis, inhibitors of apoptosis, transcription factors, kinases and ubiquitin-proteasome system, sequentially in a time-dependent way. Products of cell survival-related gene induced by propargylamines may be applied as markers of neuroprotection in clinical samples.

Involvement of type A monoamine oxidase in neurodegeneration: regulation of mitochondrial signaling leading to cell death or neuroprotection

In neurodegenerative diseases, including Parkinson's and Alzheimer's diseases, apoptosis is a common type of cell death, and mitochondria emerge as the major organelle to initiate death cascade. Monoamine oxidase (MAO) in the mitochondrial outer membrane produces hydrogen peroxide by oxidation of monoamine substrates, and induces oxidative stress resulting in neuronal degeneration. On the other hand, a series of inhibitors of type B MAO (MAO-B) protect neurons from cell death. These results suggest that MAO may be involved in the cell death process initiated in mitochondria. However, the direct involvement of MAO in the apoptotic signaling has been scarcely reported. In this paper, we present our recent results on the role of MAO in activating and regulating cell death processing in mitochondria. Type A MAO (MAO-A) was found to bind an endogenous dopaminergic neurotoxin, N-methyl(R)salsolinol, and induce apoptosis in dopaminergic SH-SY5Y cells containing only MAO-A. To examine the intervention of MAO-B in apoptotic process, human MAO-B cDNA was transfected to SH-SY5Y cells, but the sensitivity to N-methyl(R)salsolinol was not affected, even though the activity and protein of MAO-B were expressed markedly. MAO-B oxidized dopamine with production of hydrogen peroxide, whereas in control cells expressing only MAO-A, dopamine autoxidation produced superoxide and dopamine-quinone, and induced mitochondrial permeability transition and apoptosis. Rasagiline and other MAO-B inhibitors prevent the activation of apoptotic cascade and induce prosurvival genes, such as bcl-2 and glial cell line-derived neurotrophic factor, in MAO-A-containing cells. These results demonstrate a novel function of MAO-A in the induction and regulation of apoptosis. Future studies will clarify more detailed mechanism behind regulation of mitochondrial death signaling by MAO-A, and bring out new strategies to cure or ameliorate the decline of neurons in neurodegenerative disorders.

Helicobacter pylori outer membrane proteins and gastroduodenal disease

BACKGROUND AND AIMS

A number of Helicobacter pylori outer membrane proteins (OMPs) undergo phase variations. This study examined the relation between OMP phase variations and clinical outcome.

METHODS

Expression of H pylori BabA, BabB, SabA, and OipA proteins was determined by immunoblot. Multiple regression analysis was performed to determine the relation among OMP expression, clinical outcome, and mucosal histology.

RESULTS

H pylori were cultured from 200 patients (80 with gastritis, 80 with duodenal ulcer (DU), and 40 with gastric cancer). The most reliable results were obtained using cultures from single colonies of low passage number. Stability of expression with passage varied with OipA > BabA > BabB > SabA. OipA positive status was significantly associated with the presence of DU and gastric cancer, high H pylori density, and severe neutrophil infiltration. SabA positive status was associated with gastric cancer, intestinal metaplasia, and corpus atrophy, and negatively associated with DU and neutrophil infiltration. The Sydney system underestimated the prevalence of intestinal metaplasia/atrophy compared with systems using proximal and distal corpus biopsies. SabA expression dramatically decreased following exposure of H pylori to pH 5.0 for two hours.

CONCLUSIONS

SabA expression frequently switched on or off, suggesting that SabA expression can rapidly respond to changing conditions in the stomach or in different regions of the stomach. SabA positive status was inversely related to the ability of the stomach to secrete acid, suggesting that its expression may be regulated by changes in acid secretion and/or in antigens expressed by the atrophic mucosa.

Nuclear factor {kappa}B inactivation in the rat liver ameliorates short term total warm ischaemia/reperfusion injury

BACKGROUND

In hepatic ischaemia/reperfusion injury, activated liver macrophages (Kupffer cells) are dominantly regulated by a transcription factor, nuclear factor kappaB (NFkappaB), with respect to expression of inflammatory cytokines, acute phase response proteins, and cell adhesion molecules.

AIMS

We assessed whether inactivation of NFkappaB in the liver could attenuate total hepatic warm ischaemia/reperfusion injury.

METHODS

We studied rats with hepatic overexpression of inhibitor kappaBalpha super-repressor (IkappaBalpha SR) caused by a transgene introduced using an adenoviral vector. Hepatic ischaemia/reperfusion injury was induced under warm conditions by total occlusion of hepatoduodenal ligament structures for 20 minutes, followed by reperfusion. Controls included uninfected and control virus (AdLacZ) infected rats.

RESULTS

IkappaBalpha SR was overexpressed in Kupffer cells as well as in hepatocytes, blocking nuclear translocation of NFkappaB (p65) into the nucleus after reperfusion. Gene transfection with IkappaBalpha SR, but not with LacZ, markedly attenuated ischaemia/reperfusion injury, suppressing inducible nitric oxide synthase and nitrotyrosine expression in the liver. Moreover, no remarkable hepatocyte apoptosis was detected under IkappaBalpha SR overexpression.

CONCLUSIONS

Adenoviral transfer of the IkappaBalpha SR gene in the liver ameliorates short term warm ischaemia/reperfusion injury, possibly through attenuation of hepatic macrophage activation.

Roles of virD4 and cagG genes in the cag pathogenicity island of Helicobacter pylori using a Mongolian gerbil model

BACKGROUND AND AIMS

The roles of the virD4 and the cagG genes in the cag pathogenicity island of Helicobacter pylori for gastroduodenal pathogenesis are unclear and their roles in vivo have not been examined.

METHODS

Seven week old male Mongolian gerbils were inoculated with the wild type H pylori TN2GF4, its isogenic virD4, or cagG mutants. Animals were sacrificed at 4, 12, and 24 weeks after inoculation. Gastric inflammation and H pylori density were evaluated by histology, inflammatory response (as measured by interleukin (IL)-1beta mRNA levels), proliferative activity (as assessed by 5'-bromo-2'deoxyuridine labelling indices), and host systemic reaction (as measured by anti-H pylori IgG antibody).

RESULTS

Degree of gastric inflammation, proliferative activity, and mucosal IL-1beta mRNA levels remained low throughout the first 12 weeks in gerbils infected with the virD4 mutants. Degree of gastric inflammation and proliferative activity increased at 24 weeks with the virD4 mutants reaching levels comparative with those seen at four weeks with the wild-type strains. Mucosal IL-1beta mRNA levels were also increased at 24 weeks with the virD4 mutants and levels at 24 weeks were similar between the wild-type and virD4 mutants. In contrast, gerbils infected with the cagG mutants had reduced ability to colonise gerbils, and no or little gastric inflammation or proliferative activity was observed.

CONCLUSIONS

Loss of the virD4 gene temporally retarded but did not abrogate gastric inflammation. Loss of the cagG gene abolished gastric inflammation partially via reduced ability to colonise gerbils. Unknown factors related to the type IV secretion system other than CagA may influence gastric inflammation.

Replica multichannel polymer chips with a network of sacrificial channels sealed by adhesive printing method

Replica microchips for capillary array electrophoresis containing 10 separation channels (50 microm width, 50 microm depth and 100 microm pitch) and a network of sacrificial channels (100 microm width and 50 microm depth) were successfully fabricated on a poly(methyl methacrylate) (PMMA) substrate by injection molding. The strategy involved development of moving mask deep X-ray lithography to fabricate an array of channels with inclined channel sidewalls. A slight inclination of channel sidewalls, which can not be fabricated by conventional deep X-ray lithography, is highly required to ensure the release of replicated polymer chips from a mold. Moreover, the sealing of molded PMMA multichannel chips with a PMMA cover film was achieved by a novel bonding technique involving adhesive printing and a network of sacrificial channels. An adhesive printing process enables us to precisely control the thickness of an adhesive layer, and a network of sacrificial channels makes it possible to remove air bubbles and an excess adhesive, which are crucial to achieving perfect sealing of replica PMMA chips with well-defined channel and injection structures. A CCD camera equipped with an image intensifier was used to simultaneously monitor electrophoretic separations in ten micro-channels with laser-induced fluorescence detection. High-speed and high-throughput separations of a 100 bp DNA ladder and phi X174 Hae III DNA restriction fragments have been demonstrated using a 10-channel PMMA chip. The current work establishes the feasibility of mass production of PMMA multichannel chips at a cost-effective basis.

Challenge model for Helicobacter pylori infection in human volunteers

BACKGROUND

A reliable challenge model is needed to evaluate Helicobacter pylori vaccine candidates.

METHODS

A cag pathogenicity island negative, OipA positive, multiple antibiotic susceptible strain of H pylori obtained from an individual with mild gastritis (Baylor strain 100) was used to challenge volunteers. Volunteers received 40 mg of famotidine at bedtime and 10(4)-10(10) cfu of H pylori in beef broth the next morning. Infection was confirmed by (13)C urea breath test ((13)C-UBT), culture, and histology. Eradication therapy was given four or 12 weeks post challenge and eradication was confirmed by at least two separate UBTs, as well as culture and histology.

RESULTS

Twenty subjects (nine women and 11 men; aged 23-33 years) received a H pylori challenge. Eighteen (90%) became infected. Mild to moderate dyspeptic symptoms occurred, peaked between days 9 and 12, and resolved. Vomitus from one subject contained >10(3) viable/ml H pylori. By two weeks post challenge gastric histology showed typical chronic H pylori gastritis with intense acute and chronic inflammation. The density of H pylori (as assessed by cfu/biopsy) was similarly independent of the challenge dose. A minimal infectious dose was not found. Gastric mucosal interleukin 8 levels increased more than 20-fold by two weeks after the challenge.

CONCLUSION

Challenge reliably resulted in H pylori infection. Infection was associated with typical H pylori gastritis with intense polymorphonuclear cell infiltration and interleukin 8 induction in gastric mucosa, despite absence of the cag pathogenicity island. Experimental H pylori infection is one of the viable approaches to evaluate vaccine candidates.