Neuroplasticity of the left dorsolateral prefrontal cortex in patients with treatment-resistant depression as indexed with paired associative stimulation: a TMS-EEG study

Major depressive disorder affects over 300 million people globally, with approximately 30% experiencing treatment-resistant depression (TRD). Given that impaired neuroplasticity underlies depression, the present study focused on neuroplasticity in the dorsolateral prefrontal cortex (DLPFC). Here, we aimed to investigate the differences in neuroplasticity between 60 individuals with TRD and 30 age- and sex-matched healthy controls (HCs). To induce neuroplasticity, participants underwent a paired associative stimulation (PAS) paradigm involving peripheral median nerve stimulation and transcranial magnetic stimulation (TMS) targeting the left DLPFC. Neuroplasticity was assessed by using measurements combining TMS with EEG before and after PAS. Both groups exhibited significant increases in the early component of TMS-evoked potentials (TEP) after PAS (P < 0.05, paired t-tests with the bootstrapping method). However, the HC group demonstrated a greater increase in TEPs than the TRD group (P = 0.045, paired t-tests). Additionally, event-related spectral perturbation analysis highlighted that the gamma power significantly increased after PAS in the HC group, whereas it was decreased in the TRD group (P < 0.05, paired t-tests with the bootstrapping method). This gamma power modulation revealed a significant group difference (P = 0.006, paired t-tests), indicating an inverse relationship for gamma power modulation. Our findings underscore the impaired neuroplasticity of the DLPFC in individuals with TRD.

Relationship between reaction time variability on go/no go tasks and neuropsychological functioning in younger and older adults

INTRODUCTION

Early detection of cognitive impairment in older adults is important for the prevention of dementia. Intra-individual variability in reaction time (IIV-RT) during go/no-go tasks can be used for the early detection of cognitive impairment in older adults living in the community. This study aimed to determine the relationship between IIV-RT and cognitive function during go/no-go tasks and the cutoff values for determining the risk of cognitive impairment in community-dwelling older adults.

METHODS

This study included 31 older adults without cognitive impairment, 15 community-dwelling older adults with cognitive impairment, and 34 healthy young adults. All participants performed a go/no-go task to assess the IIV-RT. Additionally, older adults underwent neuropsychological testing. Based on the results of the Japanese version of the Montreal Test of Cognitive Abilities (MoCA-J), older adults were divided into those with normal cognition and those with cognitive impairment.

RESULTS

There were significant differences in the IIV-RT among groups, including a higher IIV in the cognitively impaired group than in young adults and cognitively normal older adults. Moreover, the IIV-RT was correlated with the MoCA-J (r =  -0.531, p < 0.001), Trail Making Test Part A (r = 0.571, p < 0.001), and Verbal Fluency Test scores (r =  -0.442, p = 0.002). Receiver operating curve analysis showed that the area under the curve for IIV-RT was 0.935, and the cutoff value at which the IIV-RT identified cognitive impairment was 25.37%.

CONCLUSIONS

These findings indicate that the IIV-RT during go/no-go tasks is a useful early indicator of cognitive impairment in community-dwelling older adults.

Factors associated with COVID-19 booster vaccine hesitancy: a nationwide, cross-sectional survey in Japan

OBJECTIVES

COVID-19 vaccine hesitancy/fatigue is increasing as the pandemic enters the endemic phase. The present study aimed to explore current perceptions about COVID-19 booster vaccination among the Japanese public.

STUDY DESIGN

This was a cross-sectional study.

METHODS

This cross-sectional study used data from the Japan COVID-19 and Society Internet Survey conducted in September 2021 and September 2022. The public's perceptions of COVID-19 vaccination and factors associated with COVID-19 booster vaccine hesitancy were analyzed.

RESULTS

In total, 56,735 respondents were included. In the Japan COVID-19 and Society Internet Survey 2021, 75.1% of the participants (21,126/28,118) had completed the primary vaccination series. In the 2022 survey, 74.1% of the respondents (21,216/28,617) completed the primary series of vaccination with booster doses. The proportion of fear toward COVID-19 and obtaining information about COVID-19 has decreased from 2021 to 2022. Factors independently associated with booster vaccine hesitancy were young age (range: 18-29 years; adjusted odds ratio [aOR]: 6.56), history of COVID-19 (aOR: 1.82), distrust of the Japanese government's COVID-19 prevention measures (aOR: 1.55), lack of confidence in COVID-19 vaccine efficacy (aOR: 1.30), lack of confidence in COVID-19 vaccine safety (aOR: 1.62), low reliance on the COVID-19 vaccine (aOR: 1.92), and belief in COVID-19 conspiracy theories (aOR: 1.77).

CONCLUSIONS

Providing clear and trustworthy information is critically important, especially targeted and tailored messages for the young generation, to promoting COVID-19 booster vaccination. Policymakers should therefore develop consistent and transparent communication strategies and the ability to respond promptly and flexibly to mitigate the negative impact of COVID-19 on the public while preparing for the next pandemic.

A Case Series of Intermittent Theta Burst Stimulation Treatment for Depressive Symptoms in Individuals with Autistic Spectrum Disorder: Real World TMS Study in the Tokyo Metropolitan Area

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social communication and the presence of restricted interests and repetitive behaviors. While the symptoms of ASD are present from early childhood, there has been an increase in the number of adults with ASD in recent years who visit healthcare professionals to seek the treatment of depression due to maladjustment resulting from the core symptoms and are eventually diagnosed with ASD. Currently, no treatment is available for the core symptoms of ASD, and pharmacotherapy and psychotherapy are often provided mainly for secondary disorders such as depression and anxiety. However, the effectiveness of these therapies is often limited in individuals with ASD compared to those with major depression. In this context, neuromodulation therapies such as transcranial magnetic stimulation (TMS) have gained increasing attention as potential treatments. In this case series, we retrospectively analyzed 18 cases with ASD from the TMS registry data who had failed to improve depressive symptoms with pharmacotherapy and were treated with intermittent theta burst stimulation (iTBS) therapy to the left dorsolateral prefrontal cortex (DLPFC). We also explored the relationship between treatment efficacy and clinical epidemiological profile. Our results indicated that, despite the limitations of an open-label preliminary case series, TMS therapy in the form of iTBS may have some beneficial therapeutic effects on depressive symptoms in individuals with ASD. The present findings warrant further validation through randomized, sham-controlled trials with larger sample sizes.

Investigation of Spatiotemporal Profiles of Single-Pulse TMS-Evoked Potentials with Active Stimulation Compared with a Novel Sham Condition

Identifying genuine cortical stimulation-elicited electroencephalography (EEG) is crucial for improving the validity and reliability of neurophysiology using transcranial magnetic stimulation (TMS) combined with EEG. In this study, we evaluated the spatiotemporal profiles of single-pulse TMS-elicited EEG response administered to the left dorsal prefrontal cortex (DLPFC) in 28 healthy participants, employing active and sham stimulation conditions. We hypothesized that the early component of TEP would be activated in active stimulation compared with sham stimulation. We specifically analyzed the (1) stimulus response, (2) frequency modulation, and (3) phase synchronization of TMS-EEG data at the sensor level and the source level. Compared with the sham condition, the active condition induced a significant increase in TMS-elicited EEG power in the 30-60 ms time interval in the stimulation area at the sensor level. Furthermore, in the source-based analysis, the active condition induced significant increases in TMS-elicited response in the 30-60 ms compared with the sham condition. Collectively, we found that the active condition could specifically activate the early component of TEP compared with the sham condition. Thus, the TMS-EEG method that was applied to the DLPFC could detect the genuine neurophysiological cortical responses by properly handling potential confounding factors such as indirect response noises.

Reduced signal propagation elicited by frontal transcranial magnetic stimulation is associated with oligodendrocyte abnormalities in treatment-resistant depression

BACKGROUND

The efficacy of repetitive transcranial magnetic stimulation (rTMS) to the left dorsolateral prefrontal cortex (dlPFC) has been established in patients with treatment-resistant depression (TRD), suggesting that alterations in signal propagation from the left dlPFC to other brain regions may be linked to the pathophysiology of TRD. Alterations at the cellular level, including dysfunction of oligodendrocytes, may contribute to these network abnormalities. The objectives of the present study were to compare signal propagation from the left dlPFC to other neural networks in patients with TRD and healthy controls. We used TMS combined with electroencephalography to explore links between cell-specific gene expression and signal propagation in TRD using a virtual-histology approach.

METHODS

We examined source-level estimated signal propagation from the left dlPFC to the 7 neural networks in 60 patients with TRD and 30 healthy controls. We also calculated correlations between the interregional profiles of altered signal propagation and gene expression for 9 neural cell types derived from the Allen Human Brain Atlas data set.

RESULTS

Signal propagation from the left dlPFC to the salience network was reduced in the θ and α bands in patients with TRD (p = 0.0055). Furthermore, this decreased signal propagation was correlated with cellspecific gene expression of oligodendrocytes (p < 0.000001).

LIMITATIONS

These results show only part of the pathophysiology of TRD, because stimulation was limited to the left dlPFC.

CONCLUSION

Reduced signal propagation from the left dlPFC to the salience network may represent a pathophysiological endophenotype of TRD; this finding may be associated with reduced expression of oligodendrocytes.

Accessory right hepatic artery and aberrant bile duct in the hepatocystic triangle: a rare case with clinical implications

Awareness of variations in the hepatic vasculature and biliary system is extremely important for avoiding iatrogenic injury in upper-abdominal surgery. The objective of this study is to describe a rare case of abnormal vascular and biliary structures in the hepatocystic triangle (HCT) (the modern Calot's triangle). During anatomical dissection of the celiac trunk (CT) in an old man, the authors observed the presence of a hepatosplenic trunk arising from the CT and bifurcating into common hepatic and splenic arteries. The common hepatic artery divided into hepatic artery proper and gastroduodenal artery. The presence of accessory right hepatic artery (ARHA) arising from the superior mesenteric artery was also notable. The aberrant artery ascended retropancreatically ventral to the splenic vein, then posterolaterally to the portal vein before termination into the right hepatic lobe in the HCT. Within this triangle, there was an aberrant bile duct originating in the right hepatic lobe and ending in the common hepatic duct. This accessory duct crossed the ARHA and an associated branch (the cystic artery). There is no known previous report on the co-existence of an AHAR and an aberrant bile duct within the HCT, in addition to the hepatosplenic trunk. The clinical implications of the current case are addressed in discussion.

Professional dental care provision systems for persons with disabilities by prefecture in Japan

OBJECTIVE

The number of persons with disabilities has increased and aged. Although it is important to maintain good oral health to extend healthy life expectancy, it is difficult for such people. This study aimed to analyze regional disparities in dental care provision systems for disabled people and to propose measures for the establishment of an appropriate system.

BASIC RESEARCH DESIGN

To examine regional disparities in dental care provision systems for persons with disabilities, the number of practicing dentists and dental clinics per 100,000 population, dentists certified by the Japanese Society for Disability and Oral Health, and institutions with certified dentists per 100,000 disabled persons for each prefecture were calculated. The Gini coefficient of each was also calculated to visualize and analyze regional disparities.

RESULT

The Gini coefficients were 0.09 and 0.07 for practicing dentists and dental clinics and 0.32 and 0.28 for the certified dentists and institutions with the certified dentists, respectively. Dental institutions for the disabled abounded in the three metropolitan areas: Tokyo, Aichi, and Osaka, and their density tended to be lower in northern and southern Japan. In prefectures with few such institutions, there was no correlation between the number of institutions and prefectural residents' income, and some prefectures had similar incomes but had many institutions.

CONCLUSION

The distribution of dental care to the disabled is highly uneven in Japan, therefore, a system needs to be established to address this issue.

Advanced pathologic study for definite diagnosis of mitochondrial cardiomyopathy

 

Mitochondrial cardiomyopathy (MCM) is usually recognized as one of the phenotypes of systemic mitochondrial disease. However if there are no cardiac symptoms, it is difficult to make a definite diagnosis because of various cardiovascular phenotypes and no diagnostic criteria in pathological examination. To add myocardial pathology to the diagnostic criteria for mitochondrial respiratory chain disorders, which is the gold standard in the diagnosis of mitochondrial diseases, we performed quantitative analysis of mitochondria using electron microscopy and immunohistopathologic analysis with respiratory chain enzyme antibodies. Ten patients with hypertrophic or restrictive cardiomyopathy who had undergone endomyocardial biopsy were studied. Respiratory chain enzymatic assay and genetic study were performed and four patients were diagnosed with MCM. Using electron microscopy with quantitative analysis, volume density of mitochondria within cardiac muscle cells was significantly increased in the MCM group compared to the non-MCM group (p=0.013). Immunohistopathologic results were compatible with the result of the respiratory chain enzymatic assay. These advanced pathological tests can distinguish MCM from other cardiomyopathies.

Results of immunopathologic study

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Practical Research Project for Rare/Intractable Diseases from the Japan Agency for Medical Research and Development, AMED.

Hypergravity and microgravity exhibited reversal effects on the bone and muscle mass in mice

Spaceflight is known to induce severe systemic bone loss and muscle atrophy of astronauts due to the circumstances of microgravity. We examined the influence of artificially produced 2G hypergravity on mice for bone and muscle mass with newly developed centrifuge device. We also analyzed the effects of microgravity (mostly 0G) and artificial produced 1G in ISS (international space station) on mouse bone mass. Experiment on the ground, the bone mass of humerus, femur and tibia was measured using micro-computed tomography (μCT), and the all bone mass was significantly increased in 2G compared with 1G control. In tibial bone, the mRNA expression of bone formation related genes such as Osx and Bmp2 was elevated. The volume of triceps surae muscle was also increased in 2G compared with 1G control, and the mRNA expression of myogenic factors such as Myod and Myh1 was elevated by 2G. On the other hand, microgravity in ISS significantly induced the loss of bone mass on humerus and tibia, compared with artificial 1G induced by centrifugation. Here, we firstly report that bone and muscle mass are regulated by the gravity with loaded force in both of positive and negative on the ground and in the space.

X-Ray Spectrometer for EXAFS Using a Position Sensitive Detector

An active recording x-ray crystal spectrometer for extended x-ray absorption fine structure (EXAFS) has been built using a position sensitive detector of the self scanning photodiode array (SSPA) type. The SSPA detector has energy and position sensitivity for x-rays. The spectrometer was applied to the measurement for EXAFS of the several compounds in foil, powder and liquid states. The spectra can be obtained rapidly, and compare very well with other methods. We found that the SSPA detector is very useful for the measurement of EXAFS.

Beta-Cryptoxanthin Inhibits Lipopolysaccharide-Induced Osteoclast Differentiation and Bone Resorption via the Suppression of Inhibitor of NF-κB Kinase Activity

Beta-cryptoxanthin (β-cry) is a typical carotenoid found abundantly in fruit and vegetables such as the Japanese mandarin orange, persimmon, papaya, paprika, and carrot, and exerts various biological activities (e.g., antioxidant effects). We previously reported that β-cry suppressed lipopolysaccharide (LPS)-induced osteoclast differentiation via the inhibition of prostaglandin (PG) E₂ production in gingival fibroblasts and restored the alveolar bone loss in a mouse model for periodontitis in vivo. In this study, we investigated the molecular mechanism underlying the inhibitory effects of β-cry on osteoclast differentiation. In mouse calvarial organ cultures, LPS-induced bone resorption was suppressed by β-cry. In osteoblasts, β-cry inhibited PGE₂ production via the downregulation of the LPS-induced mRNA expression of cyclooxygenase (COX)-2 and membrane-bound PGE synthase (mPGES)-1, which are PGE synthesis-related enzymes, leading to the suppression of receptor activator of NF-κB ligand (RANKL) mRNA transcriptional activation. In an in vitro assay, β-cry directly suppressed the activity of the inhibitor of NF-κB kinase (IKK) β, and adding ATP canceled this IKKβ inhibition. Molecular docking simulation further suggested that β-cry binds to the ATP-binding pocket of IKKβ. In Raw264.7 cells, β-cry suppressed RANKL-mediated osteoclastogenesis. The molecular mechanism underlying the involvement of β-cry in LPS-induced bone resorption may involve the ATP-competing inhibition of IKK activity, resulting in the suppression of NF-κB signaling.

Spontaneous endometriosis in cynomolgus monkeys as a clinically relevant experimental model

STUDY QUESTION

Does spontaneous endometriosis in cynomolgus monkeys have the characteristics required of a good experimental model?

SUMMARY ANSWER

Spontaneous endometriosis in cynomolgus monkeys exhibited similar clinicopathological characteristics to the human disease and was useful as an experimental model.

WHAT IS KNOWN ALREADY

The prevalence of endometriosis in autopsied cynomolgus monkeys (Macaca fascicularis) in a breeding colony was reported to be 28.7% in 1993. The histopathological findings we reported recently showed that components of spontaneous endometriosis were not only endometriotic epithelium and stromal cells (CD10-positive) with hemorrhage and inflammation, but also smooth muscle metaplasia and nerve fibers.

STUDY DESIGN, SIZE, DURATION

During routine medical examinations at a research facility from 2008 to 2012, 614 female cynomolgus monkeys of reproductive age (6-25 years) were screened for endometriosis by the presence of regular menstrual bleeding, serum CA125 levels and palpation of the abdomen. In total, 29 monkeys were selected as subjects for the following study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Of the 29 monkeys selected, 15 were diagnosed with endometriosis by laparoscopy and/or open surgery. The monkeys were monitored by observing their general condition, and eight of these were monitored using laparoscopy and MRI. In addition, to investigate appropriate screening parameters and endometriosis-associated biological parameters in monkeys, we retrospectively examined general laboratory parameters that correlate to the menstrual cycle and disease status.

MAIN RESULTS AND THE ROLE OF CHANCE

The combination of CA125 serum levels (this was a useful marker for chocolate cysts), palpation of the abdomen, and fecal abnormalities was the most efficient screening method for diagnosing monkeys with endometriosis. Each animal could be diagnosed and assigned a disease stage by laparoscopy. While monitoring the disease stage by laparoscopy and/or MRI, disease status in individual monkeys was mainly stable or was progressive for 2-7 months. The detection rate by screening was low (15/614) but age-specific analysis suggests that screening would be more efficient if a colony for an endometriosis model is maintained with 11-20-year olds. As an endometriosis-associated biological parameter, the decrease in food consumption that coincided with menstruation was selected and correlated well (R2 value = 0.8239) with disease status (according to a modified adhesion revised American Fertility Society score).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Peritoneal fluid was not analyzed because a smaller amount is produced in cynomolgus monkeys than in baboons. Although clinical endometriosis-associated pain is evaluated in women using a visual analog scale, pain could not be directly evaluated in this non-human primate model.

WIDER IMPLICATIONS OF THE FINDINGS

Although cynomolgus monkeys are relatively small (2-5 kg) primates, laparoscopy and MRI make it possible to evaluate spontaneous endometriosis in these monkeys and to monitor its development over time. Spontaneous endometriosis in cynomolgus monkeys is a useful model for evaluating disease progress and drug efficacy because they have similar lesions to those in humans, and conventional laboratory methods and parameters for assessment are well established.

STUDY FUNDING/COMPETING INTEREST(S)

No external funds were used for this study. A.N.-K., K.T., H.T., A.K. and M.S. are full-time employees of Chugai Pharmaceutical Co., Ltd. R.K. received a consultancy fee from Chugai Pharmaceutical Co., Ltd. and lecture fees from Chugai Pharmaceuticals, Japan Vaccine Co. Ltd., Merck & Co., Mochida Co. Ltd., Roche Diagnostics, and BD, unrelated to the submitted work. S.N., S.O. and T.S. have nothing to declare.

Web survey-based selection of controls for epidemiological analyses of a multi-prefectural outbreak of enterohaemorrhagic Escherichia coli O157 in Japan associated with consumption of self-grilled beef hanging tender

An outbreak of enterohaemorrhagic Escherichia coli O157 occurred in multiple prefectures of Japan in November 2009. We conducted two case-control studies with trace-back and trace-forward investigations to determine the source. The case definition was met by 21 individuals; 14 (66.7%) were hospitalised, but no haemolytic uraemic syndrome, acute encephalopathy or deaths occurred. Median age was 23 (range 12-48) years and 14 cases were male (66.7%). No significant associations with food were found in a case-control study by local public health centres, but our matched case-control study using Internet surveys found that beef hanging tender (or hanger steak), derived from the diaphragm of the cattle, was significantly associated with illness (odds ratio = 15.77; 95% confidence interval, 2.00-124.11). Pulsed-field gel electrophoresis analysis of isolates from patients and the suspected food showed five different patterns: two in faecal and food samples, and another three in patient faecal samples only, although there were epidemiological links to the meat consumed at the restaurants. Trace-back investigation implicated a common food processing company from outside Japan. Examination of the logistics of the meat processing company suggested that contamination did not occur in Japan. We concluded that the source of the outbreak was imported hanging tender. This investigation revealed that Internet surveys could be useful for outbreak investigations.

Venous superdrained gastric tube pull-up procedure for hypopharyngeal and cervical esophageal reconstruction reduces postoperative anastomotic leakage and stricture

Gastric pull-up is a common procedure to reconstruct the continuity of the upper digestive tract after esophageal resection. However, this technique sometimes causes postoperative anastomotic leakage or stricture, resulting from insufficient blood flow at the distal end. To overcome this problem, additional microvascular venous anastomoses were performed. The purpose of this study was to compare the outcomes of post-surgical anastomotic leakage and stricture in patients with and without additional microvascular venous superdrainage after cervical esophageal and hypopharyngeal resection and gastric tube reconstruction. A total of 29 consecutive patients with esophageal or hypopharyngeal cancer who underwent total esophagectomy and hypopharyngectomy with gastric tube reconstruction in the National Organization Nagasaki Medical Center between April 2014 and May 2016 were analyzed in this study. Of these patients, 20 underwent additional venous anastomoses (superdrainage group), and 9 did not undergo additional procedures (standard group). We compared the frequency of post-surgical stricture and leakage in the two groups retrospectively. Three of nine patients (33.3%) developed postoperative leakage in the standard group, and 1 of 20 (5.0%) did so in the superdrainage group. Six of nine patients (66.7%) showed postoperative anastomotic stricture in the standard group, but none did so in the superdrainage group. Patients who did not undergo additional venous superdrainage were significantly more likely to develop postsurgical leakage (P < 0.05, Chi-square test) and anastomotic stricture (P < 0.001, Chi-square test). Our study revealed that only additional venous anastomoses could reduce the incidence of postoperative anastomotic leakage and stricture. This procedure is of merit to perform after total esophagectomy and hypopharyngectomy with gastric tube reconstruction.

Endovascular Stenting for Pseudoaneurysms of the Cervical Carotid Artery

The authors report two cases of pseudoaneurysm of the cervical carotid artery treated with endovascular stenting. One patient presented with cerebral ischemia due to traumatic carotid dissection and underwent stent placement 3 weeks after injury when the wide-necked pseudoaneurysm was seen to enlarge at the dissecting portion.

The aneurysm thrombosed while the carotid artery remained patent without ischemic complications for 2 years. The other patient developed repeated massive bleeding from an exposed pseudoaneurysm at the right carotid-subclavian junction resulting from radiotherapy for thyroid cancer with subsequent skin infection.

Since skin grafting failed and two attempts at coil embolization resulted in compaction with recurrent enlargement of the aneurysm, endovascular stenting was performed with endosaccular coil packing between the stent struts. Hemostasis was achieved for 2 months. Both cases illustrate successes of the stent in highly difficult situations.

Sudden infant death due to Lactococcal infective endocarditis

Infective endocarditis (IE) of infants is rare, most of which occur associated with congenital heart disease or its cardiac surgery. We experienced a case of sudden death of a four-month-old male infant without congenital heart disease. It was elucidated by postmortem examination that the dead had suffered severe IE, which led him to death. In the microbiological genetic analysis using histological section, the pathogen causing inflammation in the present case was identified as Lactococcus lactis subspecies, although Staphylococci have been reported to be common and important one. Previously reported infectious diseases by Lactococcus lactis subspecies were all adult cases and this is the first report of an infantile death due to Lactococcal IE according to our knowledge. Any fatal disease may be included in sudden death cases targeted for forensic autopsy, even if it is rare. It is expected for forensic pathologists that they note such case and share each experience among themselves and other medical fields to develop a strategy for prevention.

Monitoring gastric cancer progression with circulating tumour DNA

Background:

Circulating tumour DNA (ctDNA) is an emerging candidate biomarker for malignancies and may be useful for monitoring the disease status of gastric cancer.

Methods:

We performed targeted deep sequencing of plasma cell-free DNA (cfDNA) by massively parallel sequencing in patients with tumours harbouring TP53 mutations. The quantitative values of TP53-ctDNA during the clinical course were compared with the tumour status.

Results:

Three out of ten patients with TP53 mutations in primary tumours showed detectable TP53 mutation levels in preoperative cfDNA. Although the cfDNA concentrations were not always reflective of the disease course, the ctDNA fraction correlated with the disease status.

Conclusions:

ctDNA may serve as a useful biomarker to monitor gastric cancer progression and residual disease.

Simultaneous immunostaining with anti-S100P and anti-SV40 antibodies revealed the origin of BK virus-infected decoy cells in voided urine samples

BACKGROUND

Methods for determining the origin of BK virus (BKV)-infected cells (decoy cells) in clinical urine samples have not been established although they could enhance the diagnosis of BKV infection in immunocompromised patients.

METHODS

We performed simultaneous immunostaining with anti-S100P (a urothelial marker) and anti-SV40 antibodies in 66 clinical urine samples exhibiting SV40 positivity and a decoy-cell appearance on Papanicolaou staining. The clinical voided urine samples included seven cases of renal transplantation, 47 cases of cancer therapy and 12 cases of non-neoplastic disease. SurePath(™) liquid-based cytology was used for the urine samples.

RESULTS

BKV-infected cells were categorized as SV40(+)/S100P(+) and SV40 (+)/S100p(-). SV40(+)/S100P(-) cells were found in 55 cases (83.4%); nine cases (13.6%) carried both SV40(+)/S100P(-) and SV40(+)/S100P(+) cells. The former were identified as BKV infection in renal tubules and the latter in both the renal tubules and urothelial epithelia. The remaining two cases (3.0%) had only SV40(+)/S100P(+) cells of urothelial origin.

CONCLUSION

Simultaneous immunostaining with anti-S100P and anti-SV40 is a useful method for determining the origin of BKV-infected cells in clinical urine samples from immunocompromised patients such as renal transplantation recipients.

Effect of glucagon-like peptide-1 and ghrelin on liver metabolites in steers

Glucagon-like peptide 1 (GLP-1) and ghrelin have opposite regulatory effects on glucose metabolism in non-ruminants. However, mechanisms by which GLP-1 and ghrelin regulate nutrient partitioning, particularly in the liver, have been much less demonstrated in ruminants. A novel metabolomic method based on capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS) combined with multivariate statistical analysis was applied to address the GLP-1 and ghrelin-induced metabolic changes in the liver of steers. Three Holstein steers (400 ± 5.0 kg LW) fed a maintenance diet according to Japanese feeding standards were randomly assigned to three treatments (GLP-1, ghrelin and saline) in a 3 × 3 Latin square design with one week apart. Liver biopsies were taken 30 min after a single injection (1.0 μg/kg LW) of GLP-1 or ghrelin, and analysed for metabolites by Agilent CE-TOFMS system. Also, blood samples were collected for plasma hormones analysis. Results indicated that 20 and 10 liver metabolites were altered (P < 0.05) by GLP-1 and ghrelin, respectively. Pathway analysis showed that GLP-1 is involved in biochemical pathways related to glycolysis/gluconeogenesis, lipogenesis and lipid export from the liver, oxidative stress defence and protein turnover. Ghrelin was shown to be involved in pathways related to glycolysis, protein anabolism and phospholipid biosynthesis. However, plasma concentrations of insulin, growth hormone and glucagon did not differ between treatments. These results imply that GLP-1 and ghrelin are involved in multibiochemical pathways that go beyond simply regulating glucose metabolism. In addition, the effects of GLP-1 and ghrelin may potentially be independent of insulin and growth hormone, respectively.

Acute decrease in the stiffness of resting muscle belly due to static stretching

The purpose of the study was to examine the acute effect of static stretching exercise on the resting stiffness of gastrocnemius muscle belly. Ten healthy young adults performed standing wall stretching in dorsiflexion for 1 min at a time and repeated five times. Before and after stretching, the shear modulus was measured in medial and lateral heads of the resting gastrocnemius muscle with ultrasound shear-wave elastography. After the stretching, dorsiflexion range of motion (ROM) of the ankle joint increased (P < 0.01) by 3.9° and returned in 20 min. Immediately after stretching, shear modulus decreased (P < 0.01) by 14%, compared with before stretching across muscle heads. The decrease in shear modulus returned in 20 min after stretching. In the comparison group of 10 additional subjects, the standing intervention without stretching had no influence on these measures. There was a negative correlation between dorsiflexion ROM and shear modulus in either head before and after stretching. The results demonstrate the transient decreases in the stiffness of the resting gastrocnemius muscle belly and indicate that joint flexibility is greater in individuals with lower resting stiffness of the muscle belly.

Ingestion of medium chain fatty acids by lactating dairy cows increases concentrations of plasma ghrelin

The purpose of this study was to elucidate the effects of medium-chain fatty acids (MCFAs) on plasma ghrelin concentration in lactating dairy cows. Five early-lactating Holstein cows were randomly assigned to 2 dietary treatments in a crossover design with 2-wk periods. Treatments consisted of diets supplemented or not (control) with calcium salts of MCFAs (MCFA-Ca; 1.5% dry matter). Plasma hormone and metabolite concentrations in blood samples taken from the jugular vein were measured on the morning of feeding on day 14 of each period. Dry matter intake, milk protein, and lactose content of cows fed the MCFA-Ca diet were decreased compared with controls, but with no change in milk yield. Plasma ghrelin concentrations were higher in cows fed the MCFA-Ca diet; however, no significant effect was found on glucagon-like peptide-1 concentrations in plasma. Plasma insulin concentrations decreased, but plasma glucagon concentrations remained unchanged in cows fed the MCFA-Ca diet. The concentrations of nonesterified FAs, total cholesterol, and β-hydroxybutyrate in plasma increased in these cows. In conclusion, dietary MCFAs increase the plasma ghrelin concentrations in lactating dairy cows.

Interleukin 33 is induced by tumor necrosis factor alpha and interferon gamma in keratinocytes and contributes to allergic contact dermatitis

BACKGROUND

Interleukin (IL) 33, a novel member of the IL-1 family, is produced mainly by epithelial cells and endothelial cells in response to various types of stress, including necrosis. The effects of IL-33 on the immune cells involved in allergic contact dermatitis have recently been revealed in vitro. However, in vivo, the induction mechanism and function of IL-33 are not fully understood.

OBJECTIVES

Our objectives were to investigate induction of IL-33 in keratinocytes and to evaluate the functions of IL-33 and its inducers in a murine model of allergic contact dermatitis.

MATERIAL AND METHODS

KERTr cells, a human keratinocyte cell line, were cultured with various cytokines, including tumor necrosis factor (TNF) alpha and interferon (IFN) gamma. IL-33 expression was detected using quantitative reverse transcriptase polymerase chain reaction, immunocytochemistry, and Western blotting. The functions of IL-33, TNF-a, and IFN-y in allergic contact dermatitis were evaluated using a murine model.

RESULTS

TNF-alpha and IFN-gamma induced expression of IL-33 mRNA and protein in KERTr cells. Blockade of IL-33 attenuated swelling in the ears of the experimental mice. Similar effects were noted for blockade of TNF-alpha and IFN-gamma in these mice.

CONCLUSIONS

TNF-alpha and IFN-gamma induce expression of IL-33, and IL-33 produced by keratinocytes contributes to allergic contact dermatitis. Blockade of IL-33, TNF-alpha, and IFN-gamma could represent novel and potent strategies to treat allergic contact dermatitis.

Plasma concentrations and effects of glucagon-like peptide-1 (7-36) amide in calves before and after weaning

Glucagon-like peptide-1 (7-36) amide (GLP-1), secreted by the small intestine, has insulinotropic and glucose-lowering action. Basal plasma GLP-1 concentrations were measured in calves around the weaning period, the effect of short-chain fatty acids (SCFA) on plasma GLP-1 concentrations was examined, and the effects of GLP-1 administration on plasma insulin, glucagon, and glucose concentrations were measured. Thirteen Holstein bull calves were fed whole milk and solid feed and weaned at 7 wk of age. Preprandial plasma samples were obtained from 5 calves once a week from week 0 to 13 to measure basal concentrations of plasma GLP-1 and insulin (experiment 1). Four calves were intravenously administered with a mixed solution of SCFA (2.4 mmol/kg body weight [BW]) in week 2 and 11 to measure plasma GLP-1 concentrations (experiment 2). Another 4 calves were intravenously injected with GLP-1 (1.0 μg/kg BW) to elucidate the response of plasma insulin, glucagon, and glucose concentrations in week 1, 2, 4, 6, 7, 9, 11, and 13 (experiment 3). In experiment 1, age and weaning did not affect preprandial basal concentrations of plasma GLP-1 throughout the experimental period. Preprandial insulin concentrations increased after weaning (P < 0.05), and GLP-1 and insulin were more strongly correlated postweaning than preweaning. In experiment 2, intravenous treatment with SCFA increased plasma GLP-1 concentrations in both week 2 and 11 (P < 0.05.) In experiment 3, intravenous GLP-1 treatment decreased plasma glucose concentrations throughout the experiment (P < 0.05), but increased plasma insulin concentrations only after weaning (P < 0.05). Treatment with GLP-1 did not affect plasma glucagon concentrations, regardless of age. These results indicate that preprandial basal concentrations of plasma GLP-1 in calves are not changed by weaning, but SCFA stimulate GLP-1 secretion. The insulinotropic action of GLP-1 is detected only after weaning, but the glucose-lowering action of GLP-1 is not affected by weaning.

Expression of pancreatic trypsinogen in human extrapancreatic gastrointestinal carcinomas

Pancreatic trypsinogen expression in 149 surgically resected extrapancreatic gastrointestinal neoplasms was evaluated immunohistochemically. Immunohistochemistry was performed using a monoclonal antibody against human pancreatic trypsinogen. Pancreatic trypsinogen expression was detected in 28 of 55 gastric carcinomas (50.9%), 22 of 44 colorectal cancers (50%), 12 of 20 gallbladder cancers (60%), nine of 10 extrahepatic bile duct cancers (90%), and none of 20 hepatocellular carcinomas. The intensity of immunoreactivity in the tumor area varied from specimen to specimen, and from area to area within the same specimen. In most cases, however, immunoreactivity was more pronounced at the infiltrative margin of the tumor. Additionally, the highly differentiated carcinoma cells tended to display a focal, fine granular immunoreactive pattern, usually present in the supranuclear cytoplasm, while the poorly differentiated carcinoma cells displayed a fine granular pattern, usually present over the entire cytoplasm. These findings suggest that some extrapancreatic gastrointestinal neoplasms express pancreatic trypsinogen immunoreactive peptides, raising the possibility that secreted pancreatic trypsinogen plays a role in carcinoma invasion and metastasis, as has been shown for other classes of proteases.

Correlation between expression of urokinase-type plasminogen activator receptor and metastasis in gastric carcinoma

To clarify the interrelationship between urokinase-type plasminogen activator receptor (uPAR) and the progression of gastric cancer, uPAR expression in gastric cancer was studied by the reverse transcription (RT)-PCR and immunohistochemistry. uPAR mRNA was expressed in 44 of 46 primary gastric cancers and uPAR immunoreactivity was found in 21 (14%) of 155 tumors. uPAR immunoreactivity was also observed in the fibroblast-like cells and the inflammatory cells including macrophages. The intensity of uPAR immunoreactivity of these cells was weaker than that of cancer cells. uPAR expression detected by RT-PCR may be from cancer cells and/or non-cancerous stromal cells. uPAR immunoreactivity in cancer cells was closely associated with histologic type, nodal status, and macroscopic type. The uPAR positive tumors were closely associated with the macroscopically infiltrating type, undifferentiated type and stage IV disease. Poorly differentiated carcinomas with rich intestitial fibrosis (scirrhous carcinoma) expressed uPAR with a significantly higher incidence than the other histologic types of carcinoma. Growth of scirrhous carcinoma may be a result of a concerted action of the players in the plasminogen activator system, consisting of cancer cells and stromal elements. Furthermore, there was an intimate relationship between the grade of lymph node metastasis and uPAR tissue status. Patients with a uPAR positive tumor had a significantly poorer prognosis than those with uPAR negative tumor. These results indicate that the immunohistochemical diagnosis of uPAR tissue status on the primary tumor of gastric cancer may be a good predictor for the prognosis of patients with gastric cancer.

Potential involvement of collagen-binding proteins of Streptococcus mutans in infective endocarditis

OBJECTIVE

Streptococcus mutans, a major pathogen of dental caries, is considered to be one of the causative agents of infective endocarditis (IE). Two types of cell surface collagen-binding proteins, Cnm and Cbm, have been identified in the organism. The aim of the present study was to analyze these proteins as possible etiologic factors for IE.

MATERIALS AND METHODS

The binding activities of S. mutans strains to collagen types I, III, and IV were analyzed relative to the presence of Cnm and Cbm, as were their adhesion and invasion properties with human umbilical vein endothelial cells (HUVEC). In addition, distributions of the genes encoding Cnm and Cbm in S. mutans-positive heart valve specimens extirpated from IE and non-IE patients were analyzed by PCR.

RESULTS

Most of the Cbm-positive strains showed higher levels of binding to type I collagen as well as higher rates of adhesion and invasion with HUVEC as compared to the Cnm-positive strains. Furthermore, the gene encoding Cbm was detected significantly more frequently in heart valve specimens from IE patients than from non-IE patients.

CONCLUSIONS

These results suggest that the collagen-binding protein Cbm of S. mutans may be one of the potential important factor associated with the pathogenesis of IE.

Effect of portal haemodynamics on liver graft and intestinal mucosa after small-for-size liver transplantation in swine

BACKGROUND

After small-for-size graft (SFSG) transplantation, elevated portal venous pressure (PVP) may lead to postoperative liver damage. Herein we evaluated the impact of portocaval shunt (PCS) to control PVP on liver grafts and intestine following SFSG transplantation.

METHODS

Nineteen SFSG transplantations were performed with 30% of native liver in swine. Swine were divided into 3 groups: a high-flow shunt group (HS: n = 7), in which portal venous flow (PVF) was reduced with a 10-mm diameter PCS; a low-flow shunt group (LS: n = 6), in which PVF was reduced with a 5-mm diameter PCS, and a no-shunt group (NS: n = 6), in which no PCS was placed.

RESULTS

Seven-day survivals were 83.3% in NS, 100% in LS and 0% in HS (p = 0.0088). PVP was significantly higher in the NS group (p = 0.0001; mean ± SEM NS/LS/HS: 20.5 ± 0.7/14.0 ± 1.2/11.6 ± 0.5 mm Hg). The LS group exhibited the highest compliance (PVF/PVP; NS/LS/HS 42.7 ± 10.9/44.6 ± 4.9/37.7 ± 8.3 ml/min/mm Hg; p = 0.009), the lowest aspartate aminotransferase (NS/LS/HS 562 ± 18/370 ± 55/720 ± 130 IU/l; p = 0.0493), and suppressed deleterious alternations of the hepatic parenchyma and intestinal mucosa.

CONCLUSIONS

Portal hypertension after SFSG transplantation impaired liver and intestinal mucosa; however, inadequate portal flow impaired not only the liver, but also survival.