Toyo Institute of Food Technology

Background: Emerging evidence highlights the gut microbiota as a key contributor to the pathophysiology of irritable bowel syndrome (IBS), acting through complex interactions with intestinal motility, immune function, epithelial barrier integrity, and the gut-brain axis. This narrative review summarizes current knowledge regarding the roles of the gut microbiota and their metabolites in IBS. Summary: We discuss alterations in the gut microbiota in IBS, with particular emphasis on changes in short-chain fatty acid production, bile acid metabolism, serotonin signaling, and gas handling. Special attention is given to microbial metabolites as mediators of visceral hypersensitivity, intestinal permeability, and neuromodulation within the microbiota-gut-brain axis. Major alterations in the gut microbiota of IBS are characterized by a reduction in Bacteroidetes, Bifidobacteria, and Faecalibacterium, accompanied by an increase in Firmicutes. We explain the importance of butyrate metabolism in colonic epithelial cells for maintaining the anaerobic environment of the gut. In addition, we review the impact of diet-microbiota interactions, including FODMAP restriction, resistant starch intake, and protein fermentation, on symptom generation and microbial stability. Key Message: Although accumulating evidence supports a link between gut dysbiosis and IBS, establishing causal relationships remains challenging due to disease heterogeneity and dietary influences. Future large-scale, well-phenotyped, multi-omics studies integrating microbiota, metabolomic, and host factors are required to elucidate underlying mechanisms and to guide personalized therapeutic strategies for IBS.

<p>This study aimed to evaluate the effectiveness of yerba mate extract, both in its free and microencapsulated forms, in Vienna sausages, focusing on preserving their physical properties, antioxidant capacity, and antimicrobial activity during storage at 5°C and 12°C. The results demonstrated that microencapsulating yerba mate extract significantly reduced weight loss during sausage cooking, maintained antioxidant activity, and inhibited lipid oxidation more effectively than the free extract. Furthermore, yerba mate extract exhibited notable antimicrobial properties against pathogenic microorganisms, enhancing the microbiological safety of meat products. The analysis revealed that storage temperature significantly influenced the characteristics of sausages treated with yerba mate extract. Sausages stored at 5°C retained higher antioxidant activity, exhibited lower levels of oxidative compounds (TBARs), and showed more effective inhibition of microbial growth compared to those stored at 12°C. Regarding sensory acceptability, sausages containing free yerba mate extract were more similar to the control sample than those with the microencapsulated extract. These findings highlight the promising potential of yerba mate extract, particularly in its microencapsulated form, as a functional ingredient in sausages, contributing to physical stability, antioxidant protection, and antimicrobial properties during storage.</p>

Fig (Ficus carica L.), a deciduous fruit tree that belongs to the Moraceae family, is cultivated worldwide as an important fruit crop for raw and processed foods. Quantitative real-time PCR (RT-qPCR) is a widely used method in F. carica to elucidate expression of genes related to various physiological responses. However, no studies have identified appropriate reference genes for RT-qPCR normalization in F. carica. In this study, 12 genes were selected from the F. carica genome as candidate reference genes for normalizing target gene expression. All candidate genes exhibited high amplification efficiency and specificity in the absence of primer dimers or extra PCR amplicons. The expression levels of the candidate genes were measured in three different plant tissues (fruit, leaf, and stem) under fungal pathogen infection using RT-qPCR. Their expression stabilities were evaluated using four computational algorithms: geNorm, Normfinder, delta-Ct, and BestKeeper. The RefFinder program was also used to calculate the geometric mean of the stability rankings obtained from these algorithms. The comprehensive ranking revealed that FcYLS8, FcPP2A, and FcAP2M were the most stable reference genes under biotic stress in the fruits, leaves, and stems, respectively. In contrast, traditional reference genes such as FcACT2, FcEF-1α, FcGAPDH, FcUBC21, and FcUBQ5 exhibited relatively low expression stability in all tested tissues. This study identified and validated stable reference genes for RT-qPCR normalization in F. carica, thus providing a valuable resource for accurate gene expression studies under biotic stress and highlighting the importance of validating reference genes to ensure reliable and reproducible RT-qPCR analysis.

In recent years, surgical procedures for benign prostatic hyperplasia (BPH) have evolved to include enucleation and vaporization techniques, and minimally invasive surgical therapies (MIST) have become increasingly common. However, a 2022 survey examining the implementation status of various BPH surgical procedures in Japan reported that transurethral resection of the prostate (TURP) remained the most commonly performed procedure, accounting for 45%, followed by holmium laser enucleation of the prostate (HoLEP) at 24.3%, transurethral enucleation with bipolar (TUEB) at 12.2%, and photoselective vaporization of the prostate (PVP)/contact laser vaporization (CVP) at 8.3% [1]. Among perioperative complications, postoperative infection is a major concern that can significantly impair patients' quality of life. The administration of prophylactic antibiotics plays an important role in preventing perioperative infections; however, inappropriate long-term use not only increases the risk of adverse drug events but also promotes the development of drug-resistant bacteria. Therefore, the selection of appropriate agents and optimal administration methods is of paramount importance. According to the aforementioned survey, the duration of prophylactic antibiotic administration for TURP varied among institutions: a single dose in 38.3%, within 24 h in 20.4%, within 48 h in 27.2%, and within 72 h in 12.3%. The Japanese guidelines recommend a single-dose regimen for antibiotic prophylaxis in TURP [2]. Although adherence to these guidelines has been improving, some facilities continue to use prolonged regimens. These results indicate that compliance with the guidelines remains suboptimal, and further efforts are required to promote the appropriate use of antibiotics. A systematic review of 39 randomized controlled trials reported that prophylactic antibiotics reduced the incidence of sepsis from 3.4% to 1.4% (a 51% relative risk reduction) and decreased the rates of postoperative fever and bacteriuria by 36% and 63%, respectively [3]. These findings support the necessity of prophylactic antibiotic use in TURP. Thre present study, which demonstrated through systematic review and network meta-analysis that a single-dose regimen is sufficient, provides highly valuable evidence for clinical practice [4]. On the other hand, few studies have evaluated the effectiveness of prophylactic antibiotics in BPH surgeries other than TURP. To determine the optimal duration of antibiotic administration for patients undergoing transurethral enucleation of the prostate, a multicenter prospective RCT was conducted by the Japanese Research Group for Urinary Tract Infection (JRGU). The incidence of postoperative genitourinary tract infections did not differ significantly between patients who received a single dose of cefazolin and those who received a 3-day regimen, indicating that a single dose is sufficient for prophylaxis in patients without preoperative pyuria or bacteriuria [5]. In the future, further reports, systematic reviews, and meta-analyses are expected to clarify the necessity and optimal duration of prophylactic antibiotic administration in surgical procedures such as enucleation (e.g., HoLEP, TUEB), vaporization (e.g., PVP, CVP), and minimally invasive therapies (e.g., water vapor energy therapy [WAVE], prostatic urethral lift [PUL]), which have become increasingly popular in recent years. Moreover, the optimal duration of prophylactic antibiotic administration in high-risk cases, such as those with preoperative bacteriuria, remains uncertain and should be established through future studies. Yoshikazu Togo: writing – original draft, review, and editing. The author declares no conflicts of interest. Alessandro V. Oliveira et al. Antibiotic Prophylaxis in Men Undergoing Transurethral Resection of Prostate: A Systematic Review and Network Meta-Analysis. Doi: https://doi.org/10.1111/iju.70276.

Abstract Background Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome rather than a single entity. Left ventricular (LV) remodeling patterns may be associated with this heterogeneity. Population-based studies have shown that LV volume decreases with aging, a key factor for HFpEF development. HFpEF associated with small LV may represent a distinctive phenotype characterized by older age and unique clinical features. Purpose This study aims to investigate the characteristics and clinical outcomes of HFpEF wih small LV. Methods We analyzed 1,140 patients from PURSUIT-HFpEF registry, a multicenter prospective observational registry of acute decompensated HFpEF patients. Clinical data were collected during the compensated phase, after stabilization following acute decompensated HF treatment. The study population was divided into groups with small, normal, and large LV based on LV end-diastolic dimension per the American Society of Echocardiography references. We examined the impact of LV size on all-cause mortality. Results Of 1,140 patients, 161 (14.1%) patients were identified with small LV, and 71 (6.2%) patients were identified with large LV. Patients with small LV were older and had higher heart rates, lower systolic blood pressure, lower body mass index, higher hemoglobin levels, higher estimated glomerular filtration rate, and elevated NT pro-BNP levels. The Kaplan-Meier analysis revealed that LV size was significantly associated with mortality (Log-rank p< 0.001). After adjusting for covariates, small LV remained independently associated with mortality compared with the normal LV group (adjusted hazard ratio: 0.64 [95% confidence interval: 0.49-0.83], p<0.001). Conclusions HFpEF with small LV represents a distinct phenotype characterized by older age, elevated NT-proBNP, fewer comorbidities, and higher mortality. These findings highlight the need for tailored management strategies for this subgroup.

A 74-year-old male patient presented with painless enlargement of the right scrotum that had persisted for three months. His past medical history included a gastrojejunostomy for metastatic gastric cancer and laparoscopic right inguinal hernia repair. Tumor markers were negative. However, an ultrasound examination revealed a mosaic-patterned mass measuring 4 cm in diameter within the scrotum, while an enhanced mass within the right scrotum was shown by contrast-enhanced computed tomography, raising suspicion of a malignant tumor. Consequently, a right high orchiectomy procedure was performed. Following surgery, histopathological examination results showed nodules composed of proliferating fibroblasts and collagen fibers surrounding the affected testis, which included bundles of smooth muscle and bony fragments within. Mild chronic inflammatory cell infiltration, including lymphocytes, plasma cells, and eosinophils, was also noted extending from the perivascular region to the stroma. As a result, a diagnosis of paratesticular fibrous pseudotumor was determined. Findings obtained in the present case revealed a rare condition and indicate that paratesticular fibrous pseudotumor should be considered as a differential diagnosis when a testicular tumor condition is suspected.

Scrotal skin temperature (SST) reflects intratesticular temperature, the elevation of which has adverse effects on bilateral spermatogenesis. The present study evaluated the effects of bilateral heat stress on the semen quality of two patients with a left-sided varicocele using chronological SST measurements. Scrotal skin temperature in two patients with a left-sided varicocele was determined using a thermal imaging camera (FLIR C2, FLIR Systems, Wilsonville, OR, USA). Case 1 was a single man seeking preconception care and diagnosed with a painful Grade 2 varicocele. The value for left side SST-right side SST (ΔSST) decreased from 3.2°C to -1.2°C along with the exacerbation of the varicocele from Grade 2 to 3. A varicocelectomy was performed because of the worsening of semen quality. Case 2 was an infertile man with a painful Grade 1 varicocele. The initial ΔSST of 2.4°C was temporarily reduced to 0.6°C, followed by recovery to 2.6°C along with a clear improvement in spermatogram results. To the best of our knowledge, the present chronological findings are the first to show that bilateral elevation of intratesticular temperature in a patient with a left-sided varicocele is substantially related to the deterioration of spermatogenesis.

This study investigated the effects of retort sterilization and oxygen on meat coloration during storage of beef meatballs. Beef meatballs were prepared and retort-sterilized under different oxygen concentrations, and color changes were observed after 12 weeks of storage. In the beef meatballs processed in 21 % oxygen, the center cross-section became remarkably pinked with significantly increased a* value, resembling the undesirable persistent pinking in beef. In addition, the outer cross-section turned brown. The oxidation-reduction potential value of the pink cross-section was significantly lower than that of the brown cross-section, although the pH did not change. In addition, oxygen consumption appeared to occur after retort sterilization of the meatballs, and an assay of thiol group concentration, carboxyl compounds, and iron ion valence indicated the oxidation of salt-soluble proteins in browned meatballs. These findings suggest that the observed pinking phenomenon resulted from alterations in the oxidation-reduction state of the meat during storage.