ABSTRACT
Objective: This study was performed to demonstrate the clinical application of duodenum-preserving pancreatic head resection (DPPHR) as a surgical treatment for pancreatic neuroendocrine tumors (PNETs) in terms of both curability and maintenance of postoperative quality of life. Methods: Seven patients diagnosed with PNETs underwent DPPHR from January 2011 to December 2021 at our institution. We investigated the clinical relevance of DPPHR based on the patients' clinicopathological findings. Results: The median operative time was 492 min, and the median blood loss was 302 g. Postoperative complications were evaluated according to the Clavien-Dindo classification, and postoperative intra-abdominal bleeding was observed in one patient. Pathological examination revealed a World Health Organization classification of G1 in six patients and G2 in one patient. Microvascular invasion was observed in two patients (29%); however, no patients developed lymph node metastasis or recurrence during the follow-up period. A daughter lesion was observed near the primary tumor in one patient. All patients achieved curative resection, and no tumor specimens showed positive margins. Conclusions: DPPHR facilitates anatomical resection of the pancreatic head in patients with PNETs as well as detailed pathological evaluation of the resected specimen. Therefore, this surgical procedure is an acceptable alternative to pancreaticoduodenectomy or enucleation for patients with PNETs.
ABSTRACT
BACKGROUND: Despite advances in the treatment of cancer, pancreatic ductal adenocarcinoma (PDAC) remains highly lethal due to the lack of effective therapies. Our previous study showed that Luteolin (Lut), a flavonoid, suppressed pancreatocarcinogenesis and reduced the expression of dihydropyrimidine dehydrogenase (DPYD), an enzyme that degrades pyrimidines such as 5-fluorouracil (5-FU), in PDACs. In this study, we investigated the role of DPYD and evaluated the therapeutic potential of combining 5-FU with Lut in PDACs. METHODS AND RESULTS: PDAC cells overexpressing DPYD showed increased proliferation, and invasiveness, adding to the resistance to 5-FU. The xenograft tumors of DPYD-overexpressing PDAC cells also exhibit enhanced growth and invasion compared to the control xenograft tumors. RNA-seq analysis of the DPYD-overexpressing PDAC xenograft tumors revealed an upregulation of genes associated with metallopeptidase activity-MMP9 and MEP1A. Furthermore, the overexpression of MEP1A in PDAC was associated with invasion. Next, we investigated the combined effects of Lut, a DPYD suppressor, and 5-FU on DPYD-overexpressing xenograft tumors and PDAC of Pdx1-Cre; LSL-KrasG12D/+; Trp53flox/flox(KPPC) mice. Neither single administration of 5-FU nor Lut showed significant inhibitory effects; however, the combined administration of 5-FU and Lut exhibited a significant tumor-suppressive effect in both the xenograft tumors and KPPC models. CONCLUSION: We have elucidated that DPYD expression contributes to proliferation, invasiveness, and 5-FU resistance, in PDACs. The combination therapy of Lut and 5-FU holds the potential for enhanced efficacy against PDACs.
Subject(s)
Carcinoma, Pancreatic Ductal , Cell Proliferation , Dihydrouracil Dehydrogenase (NADP) , Fluorouracil , Luteolin , Pancreatic Neoplasms , Xenograft Model Antitumor Assays , Fluorouracil/pharmacology , Fluorouracil/therapeutic use , Animals , Humans , Dihydrouracil Dehydrogenase (NADP)/genetics , Dihydrouracil Dehydrogenase (NADP)/metabolism , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/metabolism , Mice , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/metabolism , Luteolin/pharmacology , Luteolin/therapeutic use , Cell Proliferation/drug effects , Cell Line, Tumor , Drug Resistance, Neoplasm , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Gene Expression Regulation, Neoplastic/drug effects , Mice, Nude , Neoplasm InvasivenessABSTRACT
Background: Outcomes in patients with relatively high His-bundle (HB) capture thresholds at implantation are unknown. This study aimed to compare changes in the HB capture threshold and prognosis between patients with a relatively high threshold and those with a low threshold. Methods and Results: Forty-nine patients who underwent permanent HB pacing (HBP) were divided into two groups: low (<1.25 V at 1.0 ms; n=35) and high (1.25-2.49 V; n=14) baseline HB capture threshold groups. The HB capture threshold was evaluated at implantation, and after 1 week, 1, 3, and 6 months, and every 6 months thereafter. HB capture threshold rise was defined as threshold rise ≥1.0 V at 1.0 ms compared with implantation measures. We compared outcomes between the groups. During a mean follow-up period of 34.6 months, the high-threshold group showed a trend toward a higher incidence of HB capture threshold of ≥2.5 V (50% vs. 14%; P=0.023), HBP abandonment (29% vs. 8.6%; P=0.091), lead revision (21% vs. 2.9%; P=0.065), and clinical events (all-cause death, heart failure hospitalization, and new-onset or progression of atrial fibrillation; 50% vs. 23%; P=0.089) than the low-threshold group. A baseline HB capture threshold of ≥1.25V was an independent predictor of clinical events. Conclusions: A relatively high HB capture threshold is associated with increased risk of HBP abandonment, lead revision, and poor clinical outcomes.
ABSTRACT
Biliary tract cancers (BTCs) are a group of deadly malignancies encompassing intrahepatic and extrahepatic cholangiocarcinoma, gallbladder carcinoma, and ampullary carcinoma. Here, we present the integrative analysis of 63 BTC cell lines via multi-omics clustering and genome- scale CRISPR screens, providing a platform to illuminate BTC biology and inform therapeutic development. We identify dependencies broadly enriched in BTC compared to other cancers as well as dependencies selective to the anatomic subtypes. Notably, cholangiocarcinoma cell lines are stratified into distinct lineage subtypes based on biliary or dual biliary/hepatocyte marker signatures, associated with dependency on specific lineage survival factors. Transcriptional analysis of patient specimens demonstrates the prognostic significance of these lineage subtypes. Additionally, we delineate strategies to enhance targeted therapies or to overcome resistance in cell lines with key driver gene mutations. Furthermore, clustering based on dependencies and proteomics data elucidates unexpected functional relationships, including a BTC subgroup with partial squamous differentiation. Thus, this cell line atlas reveals potential therapeutic targets in molecularly defined BTCs, unveils biologically distinct disease subtypes, and offers a vital resource for BTC research.
ABSTRACT
Isocitrate dehydrogenase 1 (IDH1) is the most commonly mutated metabolic gene across human cancers. Mutant IDH1 (mIDH1) generates the oncometabolite (R)-2-hydroxyglutarate, disrupting enzymes involved in epigenetics and other processes. A hallmark of IDH1-mutant solid tumors is T cell exclusion, whereas mIDH1 inhibition in preclinical models restores antitumor immunity. Here, we define a cell-autonomous mechanism of mIDH1-driven immune evasion. IDH1-mutant solid tumors show selective hypermethylation and silencing of the cytoplasmic double-stranded DNA (dsDNA) sensor CGAS, compromising innate immune signaling. mIDH1 inhibition restores DNA demethylation, derepressing CGAS and transposable element (TE) subclasses. dsDNA produced by TE-reverse transcriptase (TE-RT) activates cGAS, triggering viral mimicry and stimulating antitumor immunity. In summary, we demonstrate that mIDH1 epigenetically suppresses innate immunity and link endogenous RT activity to the mechanism of action of a US Food and Drug Administration-approved oncology drug.
Subject(s)
Immune Evasion , Immunity, Innate , Isocitrate Dehydrogenase , Neoplasms , Animals , Humans , Mice , Cell Line, Tumor , DNA/metabolism , DNA Demethylation , DNA Methylation , DNA Transposable Elements , Epigenesis, Genetic , Glutarates/metabolism , Immunity, Innate/genetics , Isocitrate Dehydrogenase/genetics , Isocitrate Dehydrogenase/metabolism , Mutation , Neoplasms/immunology , Neoplasms/genetics , Nucleotidyltransferases/genetics , Tumor Escape , Immune Evasion/geneticsABSTRACT
Nonalcoholic fatty liver disease (NAFLD) is fatty liver mainly related to metabolic syndrome. NAFLD with inflammation and hepatocellular damage is defined as nonalcoholic steatohepatitis (NASH), which can progress to cirrhosis and hepatocellular carcinoma. We have previously reported that a hexane insoluble fraction from an anthocyanin-rich purple rice ethanolic extract (PRE-HIF) can suppress prostate carcinogenesis. However, the extract's effect on NASH has not yet been established. In the present study, we investigated the chemopreventive effect of a PRE-HIF on NASH and liver fibrosis using a connexin 32 (Cx32) dominant negative transgenic (Cx32ΔTg) rat NASH model. Seven-week-old male Cx32ΔTg rats were fed a control diet, a high-fat diet (HFD), or an HFD with 1% PRE-HIF and intraperitoneal administration of dimethylnitrosamine for 17 weeks. Histological findings of NASH such as fat deposition, lobular inflammation, hepatocyte ballooning injury, and bridging fibrosis were observed in the HFD group but not in the control group, and all histological parameters were significantly improved by PRE-HIF treatment. Corresponding to the histological changes, increased expression of inflammatory cytokine mRNAs (TNF-α, IL-6, IL-18, IFN-γ, IL-1ß, TGF-ß1, TIMP1, TIMP2, COL1A1), along with and activation of nuclear factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK) signaling were observed in the HFD group, which was significantly decreased by PRE-HIF. The number and area of hepatic precancerous glutathione S-transferase placental form-positive foci tended to be decreased by PRE-HIF. These results indicate that intake of purple rice as a dietary supplement may reduce steatohepatitis, liver injury, and fibrosis in NASH by inactivation of NF-κB or JNK.
Subject(s)
Liver Cirrhosis , NF-kappa B , Non-alcoholic Fatty Liver Disease , Oryza , Plant Extracts , Animals , Male , NF-kappa B/metabolism , NF-kappa B/genetics , Plant Extracts/pharmacology , Rats , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/metabolism , Liver Cirrhosis/drug therapy , Liver Cirrhosis/metabolism , Oryza/chemistry , Humans , Liver/drug effects , Liver/metabolism , Liver/pathology , MAP Kinase Signaling System/drug effects , Diet, High-Fat/adverse effects , Disease Models, Animal , Signal Transduction/drug effects , Cytokines/metabolism , Cytokines/geneticsABSTRACT
Pancreatic islet transplantation is one of the clinical options for certain types of diabetes. However, difficulty in maintaining islets prior to transplantation limits the clinical expansion of islet transplantations. Our study introduces a dynamic culture platform developed specifically for primary human islets by mimicking the physiological microenvironment, including tissue fluidics and extracellular matrix support. We engineered the dynamic culture system by incorporating our distinctive microwell-patterned porous collagen scaffolds for loading isolated human islets, enabling vertical medium flow through the scaffolds. The dynamic culture system featured four 12 mm diameter islet culture chambers, each capable of accommodating 500 islet equivalents (IEQ) per chamber. This configuration calculates > five-fold higher seeding density than the conventional islet culture in flasks prior to the clinical transplantations (442 vs 86 IEQ/cm2). We tested our culture platform with three separate batches of human islets isolated from deceased donors for an extended period of 2 weeks, exceeding the limits of conventional culture methods for preserving islet quality. Static cultures served as controls. The computational simulation revealed that the dynamic culture reduced the islet volume exposed to the lethal hypoxia (< 10 mmHg) to ~1/3 of the static culture. Dynamic culture ameliorated the morphological islet degradation in long-term culture and maintained islet viability, with reduced expressions of hypoxia markers. Furthermore, dynamic culture maintained the islet metabolism and insulin-secreting function over static culture in a long-term culture. Collectively, the physiological microenvironment-mimetic culture platform supported the viability and quality of isolated human islets at high-seeding density. Such a platform has a high potential for broad applications in cell therapies and tissue engineering, including extended islet culture prior to clinical islet transplantations and extended culture of stem cell-derived islets for maturation.
Subject(s)
Collagen , Islets of Langerhans , Tissue Scaffolds , Humans , Islets of Langerhans/cytology , Islets of Langerhans/metabolism , Tissue Scaffolds/chemistry , Porosity , Cell Culture Techniques/methods , Cell Culture Techniques/instrumentation , Islets of Langerhans Transplantation/methodsABSTRACT
Evaluating the quality of isolated human islets before transplantation is crucial for predicting the success in treating Type 1 diabetes. The current gold standard involves time-intensive in vivo transplantation into diabetic immunodeficient mice. Given the susceptibility of isolated islets to hypoxia, we hypothesized that hypoxia present in islets before transplantation could indicate compromised islet quality, potentially leading to unfavorable outcomes. To test this hypothesis, we analyzed expression of 39 hypoxia-related genes in human islets from 85 deceased donors. We correlated gene expression profiles with transplantation outcomes in 327 diabetic mice, each receiving 1200 islet equivalents grafted into the kidney capsule. Transplantation outcome was post-transplant glycemic control based on area under the curve of blood glucose over 4 weeks. In linear regression analysis, DDIT4 (R = 0.4971, P < 0.0001), SLC2A8 (R = 0.3531, P = 0.0009) and HK1 (R = 0.3444, P = 0.0012) had the highest correlation with transplantation outcome. A multiple regression model of 11 genes increased the correlation (R = 0.6117, P < 0.0001). We conclude that assessing pre-transplant hypoxia in human islets via gene expression analysis is a rapid, viable alternative to conventional in vivo assessments. This approach also underscores the importance of mitigating pre-transplant hypoxia in isolated islets to improve the success rate of islet transplantation.
Subject(s)
Diabetes Mellitus, Experimental , Islets of Langerhans Transplantation , Islets of Langerhans , Humans , Animals , Islets of Langerhans Transplantation/methods , Mice , Islets of Langerhans/metabolism , Diabetes Mellitus, Experimental/therapy , Male , Diabetes Mellitus, Type 1/metabolism , Hypoxia/metabolism , Female , Cell Hypoxia , Middle Aged , Blood Glucose/metabolismABSTRACT
BACKGROUND: The incidence of alcoholic liver cirrhosis (ALC) is increasing. However, few reports have focused on ALC-derived esophageal varices (EV). We retrospectively examined differences in overall survival (OS) and EV recurrence rate in patients after endoscopic injection sclerotherapy (EIS) for ALC and hepatic B/C virus liver cirrhosis (B/C-LC). METHODS: We analyzed data from 215 patients (B/C-LC, 147; ALC, 68) who underwent EIS. The primary endpoints were OS and EV recurrence in patients with unsuccessful abstinence ALC and those with uncontrolled B/C-LC, before and after propensity score matching (PSM) to unify the patients' background. The secondary endpoints were predictors associated with these factors, as determined by multivariate analysis. RESULTS: The observation period was 1,430 ± 1,363 days. In the analysis of all patients, OS was significantly higher in the ALC group than in the B/C-LC group (p = 0.039); however, there was no difference in EV recurrence rate (p = 0.502). Ascites and history of hepatocellular carcinoma (HCC) (p = 0.019 and p < 0.001, respectively) predicted OS, whereas age and EV size predicted recurrence (p = 0.011 and 0.024, respectively). In total, 96 patients without an HCC history were matched by PSM, and there was no significant difference in OS or EV recurrence rate (p = 0.508 and 0.246, respectively). CONCLUSION: When limited to patients without a history of HCC, OS and the EV recurrence rate were comparable in patients with ALC who continued to consume alcohol and those with B/C-LC without viral control.
Subject(s)
Esophageal and Gastric Varices , Liver Cirrhosis, Alcoholic , Liver Cirrhosis , Recurrence , Sclerotherapy , Humans , Esophageal and Gastric Varices/etiology , Esophageal and Gastric Varices/therapy , Male , Female , Middle Aged , Retrospective Studies , Sclerotherapy/methods , Liver Cirrhosis, Alcoholic/complications , Liver Cirrhosis/complications , Treatment Outcome , Aged , Carcinoma, Hepatocellular/therapy , Liver Neoplasms/therapy , Adult , Propensity ScoreABSTRACT
The impact of training volume on protein requirements in endurance trained males was investigated with indicator amino acid oxidation (IAAO) methodology on a recovery day (REST) or after a 10 or 20 km run while consuming a single suboptimal protein intake (0.93 g/kg/day). Phenylalanine excretion (F13CO2; inverse proxy for whole body protein synthesis) was greatest and phenylalanine net balance was lowest on REST compared to post-exercise recovery with no difference between training volumes. Single point F13CO2 was indistinguishable from past IAAO studies using multiple protein intakes. Our results suggest that protein requirements may be greatest on recovery days but are not influenced by moderate training volumes in endurance athletes.
Subject(s)
Dietary Proteins , Physical Endurance , Rest , Humans , Male , Adult , Physical Endurance/physiology , Rest/physiology , Dietary Proteins/administration & dosage , Phenylalanine/blood , Nutritional Requirements , Running/physiology , Oxidation-Reduction , Young Adult , Endurance Training/methods , Amino AcidsABSTRACT
BACKGROUND: The TactiFlex SE catheter (TFSE, Abbott) with a contact force (CF) sensor and a laser-cut irrigated-tip has recently become available but lacks a lesion quality marker. This study aimed to explore distinctions in lesion characteristics between the TFSE and the ThermoCool SmartTouch SurroundFlow catheter (STSF, Biosense Webster), which utilizes a porous irrigated tip, and to assess the most effective application settings for the TFSE. METHODS: Lesions were generated using varying settings of radiofrequency power (30-50 W), CF (10-20 g), application duration (10-40 s), and catheter orientation (perpendicular or parallel) in an ex vivo porcine model. Comparative analysis between the TFSE and STSF was conducted for lesion characteristics and incidence of steam pops using predictive models in regression analyses. RESULTS: Among 720 applications, the TFSE exhibited a significantly lower incidence of steam pops compared to the STSF (0.6% vs. 36.8%, P < 0.001). Moreover, coefficients of determination (R2) for the TFSE were higher than those for the STSF concerning lesion depth (0.710 vs. 0.541) and volume (0.723 vs. 0.618). The lesion size generated with the TFSE was notably smaller than that with the STSF under identical application settings. Additionally, to achieve a lesion depth ≥ 4.0 mm, the TFSE required an application duration 8-12 s longer than the STSF under similar settings. CONCLUSIONS: The TFSE demonstrated a lower incidence of steam pops and superior predictability in lesion size compared to the STSF. However, the TFSE necessitated a longer application duration than the STSF to achieve an adequate lesion size.
ABSTRACT
BACKGROUND: This study aimed to investigate the effect of the use of new lithotomy stirrups-2 on the pressure dispersal on lower limbs, which may lead to the prevention of well-leg compartment syndrome (WLCS) and deep venous thrombosis (DVT), which are the most commonly associated adverse events with laparoscopic and robot-assisted rectal surgery. METHODS: A total of 30 healthy participants were included in this study. The pressure (mmHg) applied on various lower limb muscles when using conventional lithotomy stirrups-1 and new type stirrups-2 was recorded in various lithotomy positions; 1) neutral position, 2) Trendelenburg position (15°) with a 0° right inferior tilt, and 3) Trendelenburg position (15°) with a 10° right inferior tilt. Using a special sensor pad named Palm Q®, and the average values were compared between two types of stirrups. RESULTS: The use of new lithotomy stirrups-2 significantly reduced the pressure applied on the lower limb muscles in various lithotomy positions compared with the use of lithotomy stirrups-1. The most pressured lower limb muscle when using both lithotomy stirrups was the central soleus muscle, which is the most common site for the development of WLCS and DVT. In addition, when using the conventional lithotomy stirrups-1, the pressure was predominantly applied to the proximal soleus muscle; however, when using lithotomy stirrups-2, the pressure was shifted to the more distal soleus muscle. CONCLUSION: These results suggest that the new lithotomy stirrups-2 is useful in reducing the pressure load on leg muscles, especially on the proximal to central soleus, and may reduce the incidence of WLCS and DVT after rectal surgery performed in the lithotomy position. Further clinical studies are needed to determine whether the use of lithotomy stirrups-2 prevents these complications in various clinical settings.
Subject(s)
Compartment Syndromes , Digestive System Surgical Procedures , Rectal Neoplasms , Humans , Lower Extremity/surgery , Leg , Compartment Syndromes/etiology , Compartment Syndromes/prevention & control , Rectal Neoplasms/surgery , Rectal Neoplasms/complications , Digestive System Surgical Procedures/adverse effects , Postoperative Complications/etiology , Postoperative Complications/prevention & controlABSTRACT
Defining the oxygen level that induces cell death within 3-D tissues is vital for understanding tissue hypoxia; however, obtaining accurate measurements has been technically challenging. In this study, we introduce a noninvasive, high-throughput methodology to quantify critical survival partial oxygen pressure (pO2) with high spatial resolution within spheroids by using a combination of controlled hypoxic conditions, semiautomated live/dead cell imaging, and computational oxygen modeling. The oxygen-permeable, micropyramid patterned culture plates created a precisely controlled oxygen condition around the individual spheroid. Live/dead cell imaging provided the geometric information of the live/dead boundary within spheroids. Finally, computational oxygen modeling calculated the pO2 at the live/dead boundary within spheroids. As proof of concept, we determined the critical survival pO2 in two types of spheroids: isolated primary pancreatic islets and tumor-derived pseudoislets (2.43 ± 0.08 vs. 0.84 ± 0.04 mmHg), indicating higher hypoxia tolerance in pseudoislets due to their tumorigenic origin. We also applied this method for evaluating graft survival in cell transplantations for diabetes therapy, where hypoxia is a critical barrier to successful transplantation outcomes; thus, designing oxygenation strategies is required. Based on the elucidated critical survival pO2, 100% viability could be maintained in a typically sized primary islet under the tissue pO2 above 14.5 mmHg. This work presents a valuable tool that is potentially instrumental for fundamental hypoxia research. It offers insights into physiological responses to hypoxia among different cell types and may refine translational research in cell therapies.NEW & NOTEWORTHY Our study introduces an innovative combinatory approach for noninvasively determining the critical survival oxygen level of cells within small cell spheroids, which replicates a 3-D tissue environment, by seamlessly integrating three pivotal techniques: cell death induction under controlled oxygen conditions, semiautomated imaging that precisely identifies live/dead cells, and computational modeling of oxygen distribution. Notably, our method ensures high-throughput analysis applicable to various cell types, offering a versatile solution for researchers in diverse fields.
Subject(s)
Islets of Langerhans , Oxygen , Humans , Oxygen/metabolism , Hypoxia/metabolism , Islets of Langerhans/metabolism , Spheroids, Cellular/metabolism , Cell Hypoxia , Cell SurvivalABSTRACT
This short-term survey examined the effect of body part pain on subjective and objective handball performance in Japanese male national handball athletes. Fourteen athletes participated in this study. Assessments of pain in 10 body parts and subjective performance (concentration and satisfaction with body movement) were performed using a visual analog scale from 0 to 10 over four consecutive training days. Monitoring of heart rate and body acceleration during training was also performed to quantify the objective performance. Path analysis and linear mixed modeling were employed to assess the relationship between body pain scores and subjective/objective handball performance. Over the four days of the study period, the body part in which most athletes reported pain was the dominant shoulder (6 of 14 athletes), followed by the dominant knee, the dominant elbow, the dominant ankle joint, and the non-dominant ankle joint (3 of 14 athletes). The path analysis revealed that pain in the dominant elbow negatively correlated with concentration (standardized path coefficient = -0.644, p = 0.00), which was associated with satisfaction with body movement (standardized path coefficient = 0.704, p = 0.00). No significant effect of body pain on objective performance (heart rate and body acceleration) was found among the athletes in this study. The results suggested that the elite athletes were practicing with pain. Even if pain does not physically affect athletes' objective performance, pain in the upper extremities, associated with the primary handball movement of throwing, may reduce the quality of practice by lowering athletes' subjective performance.
ABSTRACT
This investigation examined the clinical implications of mild vertebral fractures in older community-dwelling residents. Focusing on the locomotion health of older individuals, the earlier reported Obuse study enrolled 415 randomly sampled Japanese residents aged between 50 and 89 years, 411 of whom underwent X-ray evaluations for pre-existing vertebral fractures. A blinded assessment of vertebral fractures based on Genant's criteria was conducted on the T5-L5 spine for rating on a severity scale. Grade 1 mild fractures were not linked to age in males, but increased with aging in females. Female participants had fewer Grade 1 and 2 fractures (P = 0.003 and 0.035, respectively) but more Grade 3 fractures (P = 0.013) than did males independently of age (Grade 1, 2, and 3: 25%, 16%, and 9% in females and 40%, 22%, and 6% in males, respectively). Weak negative correlations were observed between the number of fractures and bone mineral density in females for all fracture grades (Spearman's rho: 0.23 to 0.36, P < 0.05). Our study showed that Grade 1 mild vertebral fractures in males lacked pathological significance, while in females they potentially indicated fragility fractures and were related to poor lumbopelvic alignment.
Subject(s)
Independent Living , Spinal Fractures , Humans , Male , Female , Middle Aged , Aged , Aged, 80 and over , Risk Factors , Spinal Fractures/diagnostic imaging , Spinal Fractures/epidemiology , Spine , Bone DensityABSTRACT
White-rot fungi, such as Phanerochaete chrysosporium, are the most efficient degraders of lignin, a major component of plant biomass. Enzymes produced by these fungi, such as lignin peroxidases and manganese peroxidases, break down lignin polymers into various aromatic compounds based on guaiacyl, syringyl, and hydroxyphenyl units. These intermediates are further degraded, and the aromatic ring is cleaved by 1,2,4-trihydroxybenzene dioxygenases. This study aimed to characterize homogentisate dioxygenase (HGD)-like proteins from P. chrysosporium that are strongly induced by the G-unit fragment of vanillin. We overexpressed two homologous recombinant HGDs, PcHGD1 and PcHGD2, in Escherichia coli. Both PcHGD1 and PcHGD2 catalyzed the ring cleavage in methoxyhydroquinone (MHQ) and dimethoxyhydroquinone (DMHQ). The two enzymes had the highest catalytic efficiency (kcat/Km) for MHQ, and therefore, we named PcHGD1 and PcHGD2 as MHQ dioxygenases 1 and 2 (PcMHQD1 and PcMHQD2), respectively, from P. chrysosporium. This is the first study to identify and characterize MHQ and DMHQ dioxygenase activities in members of the HGD superfamily. These findings highlight the unique and broad substrate spectra of PcHGDs, rendering them attractive candidates for biotechnological applications.IMPORTANCEThis study aimed to elucidate the properties of enzymes responsible for degrading lignin, a dominant natural polymer in terrestrial lignocellulosic biomass. We focused on two homogentisate dioxygenase (HGD) homologs from the white-rot fungus, P. chrysosporium, and investigated their roles in the degradation of lignin-derived aromatic compounds. In the P. chrysosporium genome database, PcMHQD1 and PcMHQD2 were annotated as HGDs that could cleave the aromatic rings of methoxyhydroquinone (MHQ) and dimethoxyhydroquinone (DMHQ) with a preference for MHQ. These findings suggest that MHQD1 and/or MHQD2 play important roles in the degradation of lignin-derived aromatic compounds by P. chrysosporium. The preference of PcMHQDs for MHQ and DMHQ not only highlights their potential for biotechnological applications but also underscores their critical role in understanding lignin degradation by a representative of white-rot fungus, P. chrysosporium.
Subject(s)
Dioxygenases , Phanerochaete , Lignin/metabolism , Dioxygenases/genetics , Dioxygenases/metabolism , Phanerochaete/genetics , Homogentisate 1,2-Dioxygenase/metabolism , Proteins/metabolism , Peroxidases/genetics , Peroxidases/metabolismABSTRACT
A comprehensive analysis to survey heme-binding proteins produced by the white-rot fungus Phanerochaete chrysosporium was achieved using a biotinylated heme-streptavidin beads system. Mitochondrial citrate synthase (PcCS), glyceraldehyde 3-phosphate dehydrogenase (PcGAPDH), and 2-Cys thioredoxin peroxidase (mammalian HBP23 homolog) were identified as putative heme-binding proteins. Among these, PcCS and PcGAPDH were further characterized using heterologously expressed recombinant proteins. Difference spectra of PcCS titrated with hemin exhibited an increase in the Soret absorbance at 414 nm, suggesting that the axial ligand of the heme is a His residue. The activity of PcCS was strongly inhibited by hemin with Ki oxaloacetate of 8.7 µM and Ki acetyl-CoA of 5.8 µM. Since the final step of heme biosynthesis occurred at the mitochondrial inner membrane, the inhibition of PcCS by heme is thought to be a physiological event. The inhibitory mode of the heme was similar to that of CoA analogues, suggesting that heme binds to PcCS at His347 at the AcCoA-CoA binding site, which was supported by the homology model of PcCS. PcGAPDH was also inhibited by heme, with a lower concentration than that for PcCS. This might be caused by the different location of these enzymes. From the integration of these phenomena, it was concluded that metabolic regulations by heme in the central metabolic and heme synthetic pathways occurred in the mitochondria and cytosol. This novel pathway crosstalk between the central metabolic and heme biosynthetic pathways, via a heme molecule, is important in regulating the metabolic balance (heme synthesis, ATP synthesis, flux balance of the tricarboxylic acid (TCA) cycle and cellular redox balance (NADPH production) during fungal aromatic degradation. KEY POINTS: ⢠A comprehensive survey of heme-binding proteins in P. chrysosporium was achieved. ⢠Several heme-binding proteins including CS and GAPDH were identified. ⢠A novel metabolic regulation by heme in the central metabolic pathways was found.
Subject(s)
Biosynthetic Pathways , Phanerochaete , Animals , Heme , Phanerochaete/genetics , Hemin , Heme-Binding Proteins , MammalsABSTRACT
The frequency of metastasis to the pancreas is limited, and the frequency of metastasis of a squamous cell carcinoma of the esophagus is limited even further. The curative resection of this type of metastatic lesion has been reported for some patients; however, the survival benefit that can be attributed to these procedures has not yet been clearly determined. The patient examined in the present study was a 54-year-old man who was diagnosed with a lower thoracic esophageal cancer. Computed tomography revealed a 2-cm tumor at the tail of the pancreas. Since no other obvious distal metastases were observed, the patient underwent simultaneous surgical procedures, excising the esophageal squamous cell carcinoma and the pancreatic metastasis. A histopathological examination confirmed squamous cell carcinoma in both specimens. The patient has been free of disease for 9 months since the resection. A literature review of all relevant cases to date also demonstrated that the primary tumor site in all cases of patients with esophageal cancer presenting with metastasis to the pancreas was the lower thoracic esophagus. Complete simultaneous resections of esophageal squamous cell carcinoma and a solitary metastasis to the pancreas is beneficial and may produce favorable outcomes. However, due to the reduced number of corresponding reports, further studies are required for the confirmation of the benefits of surgery.
ABSTRACT
In this review article, we focus on recent papers on organ-preserving pancreatectomy procedures published since 2010. When comparing central pancreatectomy (CP) and distal pancreatectomy (DP), most studies have concluded that the CP group exhibited significantly lower incidence of new-onset diabetes or diabetes exacerbation than the DP group postoperatively. However, because of increased incidence of morbidities such as pancreatic fistula, the surgeon faces a considerable trade-off between increased short-term morbidity and long-term preservation of endocrine function. When the outcomes of two types of spleen-preserving DP (Kimura and Warshaw procedures) are compared, most studies mentioned the low incidence of postoperative gastric varices and splenic infarction with the Kimura procedure. Although there are several reports regarding the effect of spleen preservation on prevention of postoperative infections, no report on the contribution of spleen preservation to the prevention of overwhelming post-splenectomy infection is seen. The advantages of duodenum-preserving pancreatic head resection (DPPHR) concerning endocrine and exocrine functions continue to be subjects of discussion, mainly due to the limited number of institutions that have adopted this approach; however, DPPHR should be presented as an option for patients due to its low incidence of postoperative cholangitis. Organ-preserving pancreatectomy requires meticulous surgical techniques, and postoperative complications may increase with this surgery compared with standard pancreatectomy, which may be influenced by the surgeon's skill and the surgical facility where the procedure is performed. Nonetheless, this technique has significant long-term advantages in terms of endocrine and exocrine functions and its wider adoption in the future is expected.