ABSTRACT
This study investigated levels of eight polycyclic aromatic hydrocarbons (PAH8) compounds in both raw and processed marine products in South Korea. Katsuobushi exhibited the highest concentration of benzo[a]pyrene, at 14.22 µg/kg, exceeding the European Commission's regulation level of 5.0 µg/kg. The total PAH8 concentration in katsuobushi was 220.5 µg/kg. Among the product categories, shellfish had the highest detection rate (70%), followed by fish (19%) and crustacea (8%), with chrysene being the most prominent PAH8 congener in all marine products. Grilled fish predominantly contained pyrogenic PAHs from combustion byproducts, while shellfish primarily contained petrogenic ones from the aquatic environment. Grilling, smoking, and drying processes significantly contributed to the formation of PAH8 in these food products. Based on the results of a risk assessment using a margin of exposure approach through a total diet study, exposure to PAH8 from marine products is considered to pose low concern to the South Korean population. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01491-y.
ABSTRACT
Anthocyanins play critical roles in protecting plant tissues against diverse stresses. The complicated regulatory networks induced by various environmental factors modulate the homeostatic level of anthocyanins. Here, we show that anthocyanin accumulation is induced by brassinosteroids (BRs) in Arabidopsis (Arabidopsis thaliana) shoots and shed light on the underlying regulatory mechanism. We observed that anthocyanin levels are altered considerably in BR-related mutants, and BRs induce anthocyanin accumulation by up-regulating the expression of anthocyanin biosynthetic genes. Our genetic analysis indicated that BRASSINAZOLE RESISTANT 1 (BZR1) and PRODUCTION OF ANTHOCYANIN PIGMENT 1 (PAP1) are essential for BR-induced anthocyanin accumulation. The BR-responsive transcription factor BZR1 directly binds to the PAP1 promoter, regulating its expression. In addition, we found that intense anthocyanin accumulation caused by the pap1-D dominant mutation is significantly reduced in BR mutants, implying that BR activity is required for PAP1 function after PAP1 transcription. Moreover, we demonstrated that BZR1 physically interacts with PAP1 to cooperatively regulate the expression of PAP1 target genes, such as TRANSPARENT TESTA 8 (TT8), DIHYDROFLAVONOL 4-REDUCTASE (DFR), and LEUKOANTHOCYANIDIN DIOXYGENASE (LDOX). Our findings indicate that BZR1 functions as an integral component of the PAP1-containing transcription factor complex, contributing to increased anthocyanin biosynthesis. Notably, we also show that functional interaction of BZR1 with PAP1 is required for anthocyanin accumulation induced by low nitrogen stress. Taken together, our results demonstrate that BR-regulated BZR1 promotes anthocyanin biosynthesis through cooperative interaction with PAP1 of the MBW complex.
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Long-term changes in caregiver burden should be clarified considering that extended post-stroke disability can increase caregiver stress. We assessed long-term changes in caregiver burden severity and its predictors. This study was a retrospective analysis of the Korean Stroke Cohort for Functioning and Rehabilitation. Patients with an acute first-ever stroke were enrolled from August 2012 to May 2015. Data were collected at 6 months and 6 years after stroke onset. The caregiver burden was measured with a subjective caregiver burden questionnaire based on the Korean version of the Caregiver Burden Inventory. The caregivers' characteristics and patients' clinical and functional status were also examined at each follow-up. A high caregiver burden, which suggests a risk of burnout, was reported by 37.9% and 51.7% of caregivers at 6 months and 6 years post-stroke, respectively. Both the caregiver burden total score and proportion of caregivers at risk of burnout did not decrease between 6 months and 6 years. The patients' disability (OR = 11.60; 95% CI 1.58-85.08; p = 0.016), caregivers' self-rated stress (OR = 0.03; 95% CI 0.00-0.47; p = 0.013), and caregivers' quality of life (OR = 0.76; 95% CI 0.59-0.99; p = 0.042) were burden predictors at 6 months. At 6 years, only the patients' disability (OR = 5.88; 95% CI 2.19-15.82; p < 0.001) and caregivers' psychosocial stress (OR = 1.26; 95% CI 1.10-1.44; p = 0.001) showed significance. Nearly half of the caregivers were at risk of burnout, which lasted for 6 years after stroke onset. The patients' disability and caregivers' stress were burden predictors in both subacute and chronic phases of stroke. The findings suggest that consistent interventions, such as emotional support or counseling on stress relief strategies for caregivers of stroke survivors, may reduce caregiver burden. Further research is needed to establish specific strategies appropriate for Korean caregivers to alleviate their burden in caring for stroke patients.
Subject(s)
Caregiver Burden , Caregivers , Quality of Life , Stroke , Humans , Male , Female , Middle Aged , Stroke/psychology , Stroke/complications , Retrospective Studies , Caregivers/psychology , Caregivers/statistics & numerical data , Aged , Surveys and Questionnaires , Republic of Korea , Quality of Life/psychology , Caregiver Burden/psychology , Survivors/psychology , Survivors/statistics & numerical data , Adult , Stress, Psychological/psychology , Stress, Psychological/complications , Stress, Psychological/etiology , Stroke Rehabilitation/psychology , Stroke Rehabilitation/statistics & numerical dataABSTRACT
OBJECTIVE: The objective of this prospective study was to assess longitudinal variations in health-related quality of life (HR-QOL) in patients diagnosed with differentiated thyroid cancer (DTC) before and after thyroidectomy. METHODS: A cohort of 185 DTC patients who underwent thyroidectomy between January 2013 and December 2017 and who completed all necessary questionnaires was evaluated. Their HR-QOL was gauged using the University of Washington Quality of Life questionnaire (UW-QOL) and the City of Hope Quality of Life-Thyroid Version questionnaire (QOL-TV) both prior to surgery and at 3 months, 6 months, 1 year, 2 years, 3 years, and 5 years postoperatively. RESULTS: Out of 185 patients, 150 (81.1%) were female, with an average age of 48.7 ± 12.9 years. For both UW-QOL and QOL-TV, the total composite QOL scores notably declined from preoperative levels to 3 months postoperatively, then gradually improved over 5 years, ultimately exceeding preoperative scores. Factors such as total thyroidectomy, radioactive iodine (RAI) ablation, and postoperative hypoparathyroidism were associated with lower physical composite QOL scores. Patients who underwent remote-access thyroidectomy expressed significantly higher satisfaction with appearance compared with those who had conventional thyroidectomy. Mood and anxiety were major clinical concerns both before and after surgery, showing considerable improvement postoperatively. CONCLUSION: For DTC patients, HR-QOL experienced a significant drop 3 months postsurgery, subsequently showing gradual improvement, surpassing preoperative QOL by 5 years. Factors contributing to improved physical QOL included the utilization of remote-access thyroidectomy, less extensive thyroidectomy, and the absence of RAI ablation and hypoparathyroidism.
Subject(s)
Quality of Life , Thyroid Neoplasms , Thyroidectomy , Humans , Female , Thyroid Neoplasms/surgery , Thyroid Neoplasms/psychology , Middle Aged , Male , Adult , Longitudinal Studies , Prospective Studies , Surveys and Questionnaires , Postoperative Period , Postoperative Complications/epidemiology , Postoperative Complications/psychology , Postoperative Complications/etiology , Follow-Up StudiesABSTRACT
Avian brood parasites and their hosts display varied egg-puncture behaviors, exerting asymmetric co-evolutionary selection pressures on eggshells' breaking strength. We investigated eggshell structural and textural characteristics that may improve its mechanical performance. Parasitic eggshell calcified layers showed complex ultra- and microstructural patterns. However, stronger parasitic eggshells are not due to lower textural severity (characterized by lower preferred crystallographic orientation, larger local grain misorientation and smaller Kearns factor), but rather to grain boundary (GB) microstructure characteristics within the eggshell outermost layer (palisade layer, PL). Accordingly, the thicker the PL and the more complex the GB pathways are, the tougher the parasitic eggshells will be. These characteristics, which we can identify as a "GB Engineering" driven co-evolutionary process, further improve eggshell breaking strength in those parasitic species that suffer relatively high frequencies of egg-puncturing by congeneric or hosts. Overall, plain textural patterns are not suitable predictors for comparing mechanical performance of bioceramic materials.
ABSTRACT
Despite advances in precision oncology, cancer remains a global public health issue. In this report, proof-of-principle evidence is presented that a cell-penetrable peptide (ACP52C) dissociates transcription factor CP2c complexes and induces apoptosis in most CP2c oncogene-addicted cancer cells through transcription activity-independent mechanisms. CP2cs dissociated from complexes directly interact with and degrade YY1, leading to apoptosis via the MDM2-p53 pathway. The liberated CP2cs also inhibit TDP2, causing intrinsic genome-wide DNA strand breaks and subsequent catastrophic DNA damage responses. These two mechanisms are independent of cancer driver mutations but are hindered by high MDM2 p60 expression. However, resistance to ACP52C mediated by MDM2 p60 can be sensitized by CASP2 inhibition. Additionally, derivatives of ACP52C conjugated with fatty acid alone or with a CASP2 inhibiting peptide show improved pharmacokinetics and reduced cancer burden, even in ACP52C-resistant cancers. This study enhances the understanding of ACP52C-induced cancer-specific apoptosis induction and supports the use of ACP52C in anticancer drug development.
Subject(s)
DNA-Binding Proteins , Neoplasms , Humans , DNA-Binding Proteins/genetics , Neoplasms/genetics , Synthetic Lethal Mutations , Precision Medicine , Transcription Factors/genetics , Peptides , Phosphoric Diester Hydrolases/geneticsABSTRACT
PURPOSE: The purpose of this study was to investigate perceptions of fatherhood among fathers of high-risk neonates and their confidence regarding neonatal care. METHODS: A study was conducted of 100 fathers whose neonates had been admitted to a neonatal intensive care unit (NICU) for at least 48 hours. Perceptions of fatherhood, neonatal characteristics, and fathers' confidence regarding neonatal care were measured using a self-reported questionnaire. The survey took approximately 10 minutes to complete and was completed anonymously. The factors that affected fathers' confidence regarding neonatal care were analyzed using multiple regression. RESULTS: The scores for positive and negative perceptions of fatherhood were relatively high at 4.27 and 3.42 out of 5 points, respectively. A positive perception of fatherhood was found to influence fathers' confidence regarding neonatal care. CONCLUSION: NICU nurses should encourage fathers to effectively perform their parenting roles by implementing educational programs and interventions to promote positive perceptions of fatherhood and fathers' confidence regarding neonatal care after discharge.
ABSTRACT
Non-operative treatment is the mainstay of colonic diverticulitis, but some patients require surgery due to non-operative treatment failure. This study aims to identify risk factors for the failure of non-operative treatment of colonic diverticulitis. From January 2011 to December 2020, we retrospectively reviewed 2362 patients with non-operative treatment for first-attack acute diverticulitis. Patients were categorized into non-operative treatment success or failure groups. Clinical characteristics and serum inflammatory markers were analyzed by multivariable logistic regression to determine risk factors for non-operative treatment failure of colonic diverticulitis. Overall, 2.2% (n = 50) of patients underwent delayed surgery within 30 days (median 4.0 [3.0; 8.0]) due to non-operative treatment failure. Multivariable logistic regression identified that platelet to lymphocyte ratio (odds ratio [OR], 4.2; 95% confidence interval [CI], 0.05-0.13; p < 0.001), diabetes mellitus (OR, 2.2; 95% CI, 0.01-0.09; p = 0.025), left-sided colonic diverticulitis (OR, 4.1; 95% CI, 0.04-0.13; p < 0.001), and modified Hinchey classification (OR, 6.2; 95% CI, 0.09-0.17; p < 0.001) were risk factors for non-operative treatment failure. Platelet to lymphocyte ratio (PLR) is a potential risk factor for the non-operative treatment failure of acute first-attack colonic diverticulitis. Therefore, patients with higher PLR during non-operative treatment should be monitored with special caution.
Subject(s)
Diverticulitis, Colonic , Diverticulitis , Humans , Diverticulitis, Colonic/surgery , Retrospective Studies , Risk Factors , LymphocytesABSTRACT
New l-proline-derived bifunctional secondary amine organocatalysts were synthesized for enantioselective Michael reactions in water as a solvent. Application of these catalysts in Michael additions provided high yield (up to 97%) with high stereoselectivity (dr up to 99:1 and ee up to 99%). The effect of phenyl group at (R)-C6 in the catalyst was investigated and played a key role in successful catalysis by density functional theory computational calculations. The synthetic utility of this reaction was demonstrated by the formal synthesis of Sch 50971, which is a novel histamine H3 receptor agonist.
Subject(s)
Aldehydes , Proline , Alkenes , Water , Stereoisomerism , Molecular Structure , Ketones , Catalysis , AminesABSTRACT
Background: Hypoxic brain injury is a condition caused by restricted oxygen supply to the brain. Several studies have reported cognitive decline, particularly in spatial memory, after exposure to intermittent hypoxia (IH). However, the effect and mechanism of action of IH exposure on cognition have not been evaluated by analyzing gene expression after transcranial direct current stimulation (tDCS). Hence, the purpose of this study was to investigate the effects of tDCS on gene regulation and cognition in a rat model of IH-induced brain injury. Methods: Twenty-four 10-week-old male Sprague−Dawley rats were divided into two groups: IH exposed rats with no stimulation and IH-exposed rats that received tDCS. All rats were exposed to a hypoxic chamber containing 10% oxygen for twelve hours a day for five days. The stimulation group received tDCS at an intensity of 200 µA over the frontal bregma areas for 30 min each day for a week. As a behavior test, the escape latency on the Morris water maze (MWM) test was measured to assess spatial memory before and after stimulation. After seven days of stimulation, gene microarray analysis was conducted with a KEGG mapper tool. Results: Although there were no significant differences between the groups before and after stimulation, there was a significant effect of time and a significant time × group interaction on escape latency. In the microarray analysis, significant fold changes in 12 genes related to neurogenesis were found in the stimulation group after tDCS (p < 0.05, fold change > 2 times, the average of the normalized read count (RC) > 6 times). The highly upregulated genes in the stimulation group after tDCS were SOS, Raf, PI3K, Rac1, IRAK, and Bax. The highly downregulated genes in the stimulation group after tDCS were CHK, Crk, Rap1, p38, Ras, and NF-kB. Conclusion: In this study, we confirmed that SOS, Raf, PI3K, Rac1, IRAK, and Bax were upregulated and that CHK, Crk, Rap1, p38, Ras, and NF-kB were downregulated in a rat model of IH-induced brain injury after application of tDCS.
Subject(s)
Brain Injuries , Transcranial Direct Current Stimulation , Rats , Animals , Male , Rats, Sprague-Dawley , bcl-2-Associated X Protein , NF-kappa B , Hypoxia/genetics , Cognition , Oxygen , Phosphatidylinositol 3-KinasesABSTRACT
BACKGROUND: High-intensity repetitive task-specific practice might be the most effective strategy to promote motor recovery after stroke, and electromechanical-assisted gait training represents one of the treatment options. However, there is still difficulty in clarifying the difference between conventional gait training and electromechanically assisted gait training. METHODS: The study is a multicenter, randomized, parallel-group clinical trial for stroke patients. Three clinical research centers in Korea (Dongguk University Ilsan Hospital, Chungnam National University Hospital, and Seoul National University Bundang Hospital) will participate in the clinical trial and 144 stroke patients will be registered. Enrolled patients are assigned to two groups, an experimental group and a control group, according to a randomization table. In addition, patients are treated for half an hour (one session) five times a week for 4 weeks. Both groups carry out basic rehabilitation (central nervous system development therapy and strength exercise) and the experimental group executes robotic walking rehabilitation treatment, and the control group executes conventional gait rehabilitation treatment. The primary endpoint variable is the Functional Ambulation Category (FAC) that determines the degree of independent walking and is measured before, after, and after 4 weeks of treatment. Secondary endpoint variables are 11 variables that take into account motor function and range, measured at the same time as the primary endpoint variable. DISCUSSION: There are still insufficient data on the effectiveness of electromechanical-assisted gait training for stroke patients and large-scale research is lacking. Thus, the research described here is a large-scale study of stroke patients that can supplement the limitations mentioned in other previous studies. In addition, the clinical studies described here include physical epidemiological analysis parameters that can determine walking ability. The results of this study can lead to prove the generalizable effectiveness and safety of electromechanical-assisted gait training with EXOWALK®. TRIAL REGISTRATION: Clinical Research Information Service (CRIS), Republic of Korea KCT0003411, Registered on 30 October 2018.
Subject(s)
Stroke Rehabilitation , Stroke , Exercise Therapy/methods , Gait/physiology , Humans , Multicenter Studies as Topic , Randomized Controlled Trials as Topic , Recovery of Function , Stroke/complications , Stroke/diagnosis , Stroke/therapy , Stroke Rehabilitation/methods , Treatment Outcome , Walking/physiologyABSTRACT
The lowering blood pressure effect of vitamin C (VC) has been evaluated in various models. As VC has a fast degradation rate in the body after consumption, a study of the frequency-dependent manner of VC is essential for the sustained antihypertension effect of VC. In this study, we investigated the frequency and dose dependency of vitamin C (VC) on blood pressure reduction in spontaneously hypertensive rats (SHRs). Wistar-Kyoto rats (WKYs) and SHRs were orally administered tap water or VC (250, 500, 1000, and 2000 mg/60 kg/day). Blood pressures were measured using the tail-cuff method, and thoracic aortas, liver, and blood were harvested from sacrificed rats after 8 weeks to measure angiotensinogen, angiotensin-converting enzyme (ACE) I, endothelial nitric oxide synthase (eNOS), and total nitric oxide (NOx) concentration. VC decreased blood pressure from the fourth week with no significant differences between doses. The twice-a-day administration of VC decreased blood pressure from the second week, and the blood pressure in these groups was close to that of the WKY group in the eighth week. Treatment with once a day VC decreased ACE I production which was further significantly reduced in twice a day groups. Angiotensinogen and eNOS production were increased upon VC treatment but were not significant among groups. The NOx content was decreased by VC treatment. These results suggest that VC lowers blood pressure in SHRs by directly targeting ACE I production in a frequency-dependent manner and may improve endothelial function depending on the frequency of administration.
ABSTRACT
Vancomycin and ß-lactams are clinically important antibiotics that inhibit the formation of peptidoglycan cross-links, but their binding targets are different. The binding target of vancomycin is d-alanine-d-alanine (d-Ala-d-Ala), whereas that of ß-lactam is penicillin-binding proteins (PBPs). In this study, we revealed the divergent effects of peptidoglycan (PG) carboxypeptidase DacA on vancomycin and ß-lactam resistance in Escherichia coli and Bacillus subtilis. The deletion of DacA induced sensitivity to most ß-lactams, whereas it induced strong resistance toward vancomycin. Notably, both phenotypes did not have a strong association with ld-transpeptidases, which are necessary for the formation of PG 3-3 cross-links and covalent bonds between PG and an Lpp outer membrane (OM) lipoprotein. Vancomycin resistance was induced by an increased amount of decoy d-Ala-d-Ala residues within PG, whereas ß-lactam sensitivity was associated with physical interactions between DacA and PBPs. The presence of an OM permeability barrier strongly strengthened vancomycin resistance, but it significantly weakened ß-lactam sensitivity. Collectively, our results revealed two distinct functions of DacA, which involved inverse modulation of bacterial resistance to clinically important antibiotics, ß-lactams and vancomycin, and presented evidence for a link between DacA and PBPs. IMPORTANCE Bacterial PG hydrolases play important roles in various aspects of bacterial physiology, including cytokinesis, PG synthesis, quality control of PG, PG recycling, and stress adaptation. Of all the PG hydrolases, the role of PG carboxypeptidases is poorly understood, especially regarding their impacts on antibiotic resistance. We have revealed two distinct functions of PG carboxypeptidase DacA with respect to antibiotic resistance. The deletion of DacA led to sensitivity to most ß-lactams, while it caused strong resistance to vancomycin. Our study provides novel insights into the roles of PG carboxypeptidases in the regulation of antibiotic resistance and a potential clue for the development of a drug to improve the clinical efficacy of ß-lactam antibiotics.
Subject(s)
Peptidoglycan , beta-Lactams , Alanine/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , Carboxypeptidases/genetics , Escherichia coli/genetics , Escherichia coli/metabolism , Peptidoglycan/metabolism , Vancomycin/metabolism , Vancomycin/pharmacology , Vancomycin Resistance , beta-Lactams/metabolism , beta-Lactams/pharmacologyABSTRACT
Electromechanical-assisted gait training may be an effective intervention to promote motor recovery after brain injury. However, many studies still have difficulties in clarifying the difference between electromechanical-assisted gait training and conventional gait training. To evaluate the effectiveness of electromechanical-assisted gait training compared to that of conventional gait training on clinical walking function and gait symmetry of stroke patients. We randomly assigned patients with stroke (n = 144) to a control group (physical therapist-assisted gait training) and an experimental group (electromechanical gait training). Both types of gait training were done for 30 min each day, 5 days a week for 4 weeks. The primary endpoint was the change in functional ambulatory category (FAC). Secondary endpoints were clinical walking functions and gait symmetries of swing time and step length. All outcomes were measured at baseline (pre-intervention) and at 4 weeks after the baseline (post-intervention). FAC showed significant improvement after the intervention, as did clinical walking functions, in both groups. The step-length asymmetry improved in the control group, but that in the experimental group and the swing-time asymmetry in both groups did not show significant improvement. In the subgroup analysis of stroke duration of 90 days, FAC and clinical walking functions showed more significant improvement in the subacute group than in the chronic group. However, gait symmetries did not show any significant changes in either the subacute or the chronic group. Electromechanically assisted gait training by EXOWALK was as effective as conventional gait training with a physiotherapist. Although clinical walking function in the subacute group improved more than in the chronic group, gait asymmetry did not improve for either group after gait training.Trial registration: KCT0003411 Clinical Research Information Service (CRIS), Republic of Korea.
Subject(s)
Brain Injuries , Stroke Rehabilitation , Stroke , Brain Injuries/complications , Gait , Humans , WalkingABSTRACT
Metformin is associated with good tumor response in preoperative concurrent chemoradiotherapy (CCRT) for rectal cancer. This study aims to demonstrate that the timing of metformin is related to the tumor response on preoperative CCRT for rectal cancer. From January 2010 to December 2017, 232 patients who underwent curative resection after preoperative CCRT were reviewed. Patients were divided into groups with or without diabetes or metformin. The timing of metformin administration was divided based on before and from initiation of CCRT. Multivariate logistic regression analysis was used to identify predictors for tumor response. Tumor downstaging (p = 0.02) and good response rates of tumor regression grade (TRG) (p = 0.008) were significantly higher in the group administered metformin before CCRT than other groups. In the multivariate analysis, metformin administration before CCRT was a significant factor in predicting tumor downstaging [odds ratio (OR) 10.31, 95% confidence interval (CI) 1.76-102.08, p = 0.02] and good TRG (OR 12.55, 95% CI 2.38-80.24, p = 0.004). In patients with rectal cancer who underwent preoperative CCRT, neoadjuvant therapy of metformin before CCRT was significantly associated with good tumor response.
Subject(s)
Diabetes Mellitus , Metformin , Rectal Neoplasms , Chemoradiotherapy , Diabetes Mellitus/pathology , Humans , Metformin/therapeutic use , Neoadjuvant Therapy , Neoplasm Staging , Rectal Neoplasms/pathology , Retrospective Studies , Treatment OutcomeABSTRACT
Transcranial alternating current stimulation (tACS) is a neuromodulation procedure that is currently studied for the purpose of improving cognitive function in various diseases. A few studies have shown positive effects of tACS in Alzheimer's disease (AD). However, the mechanism underlying tACS has not been established. The purpose of this study was to investigate the mechanism of tACS in five familial AD mutation (5xFAD) mouse models. We prepared twenty 4-month-old mice and divided them into four groups: wild-type mice without stimulation (WT-NT group), wild-type mice with tACS (WT-T group), 5xFAD mice without stimulation (AD-NT group), and 5xFAD mice with tACS (AD-T group). The protocol implemented was as follows: gamma frequency 200 µA over the bilateral frontal lobe for 20 min over 2 weeks. The following tests were conducted: excitatory postsynaptic potential (EPSP) recording, Western blot analysis (cyclic AMP response element-binding (CREB) proteins, phosphorylated CREB proteins, brain-derived neurotrophic factor, and parvalbumin) to examine the synaptic plasticity. The EPSP was remarkably increased in the AD-T group compared with in the AD-NT group. In the Western blot analysis, the differences among the groups were not significant. Hence, tACS can affect the long-lasting enhancement of synaptic transmission in mice models of AD.
ABSTRACT
Heme, a porphyrin ring complexed with iron, is a metalloprosthetic group of numerous proteins involved in diverse metabolic and respiratory processes across all domains of life, and is thus considered essential for respiring organisms. Several microbial groups are known to lack the de novo heme biosynthetic pathway and therefore require exogenous heme from the environment. These heme auxotroph groups are largely limited to pathogens, symbionts, or microorganisms living in nutrient-replete conditions, whereas the complete absence of heme biosynthesis is extremely rare in free-living organisms. Here, we show that the acI lineage, a predominant and ubiquitous free-living bacterial group in freshwater habitats, is auxotrophic for heme, based on the experimental or genomic evidence. We found that two recently cultivated acI isolates require exogenous heme for their growth. One of the cultured acI isolates also exhibited auxotrophy for riboflavin. According to whole-genome analyses, all (n = 20) isolated acI strains lacked essential enzymes necessary for heme biosynthesis, indicating that heme auxotrophy is a conserved trait in this lineage. Analyses of >24,000 representative genomes for species clusters of the Genome Taxonomy Database revealed that heme auxotrophy is widespread across abundant but not-yet-cultivated microbial groups, including Patescibacteria, Marinisomatota (SAR406), Actinomarinales (OM1), and Marine groups IIb and III of Euryarchaeota Our findings indicate that heme auxotrophy is a more common phenomenon than previously thought, and may lead to use of heme as a growth factor to increase the cultured microbial diversity.
Subject(s)
Fresh Water/microbiology , Heme/metabolism , Archaea/genetics , Archaea/metabolism , Bacteria/genetics , Bacteria/metabolism , Biodiversity , Biosynthetic Pathways , Ecosystem , Genome, Bacterial , RiboflavinABSTRACT
The role of matrix metalloproteinase-2 (MMP-2) in tumor cell migration has been widely studied, however, the characteristics and effects of MMP-2 in clinical sample of metastatic colorectal cancer (CRC) remain poorly understood. Here, in order to unveil the perturbed proteomic signal during MMP-2 induced cancer progression, we analyzed plasma proteome of CRC patients according to disease progression, HCT116 cancer secretome upon MMP-2 knockdown, and publicly available CRC tissue proteome data. Collectively, the integrative analysis of multi-layered proteomes revealed that a protein cluster containing EMT (Epithelial-to-Mesenchymal Transition)-associated proteins such as CD9-integrin as well as MMP-2. The proteins of the cluster were regulated by MMP-2 perturbation and exhibited significantly increased expressions in tissue and plasma as disease progressed from TNM (Tumor, Node, and Metastasis) stage I to II. Furthermore, we also identified a plausible association between MMP-2 up-regulation and activation of focal adhesion kinase signaling in the proteogenomic analysis of CRC patient tissues. Based on these comparative and integrative analyses, we suggest that the high invasiveness in the metastatic CRC resulted from increased secretion of MMP-2 and CD9-integrin complex mediated by FAK signaling activation.
Subject(s)
Colorectal Neoplasms/metabolism , Focal Adhesion Kinase 1/metabolism , Matrix Metalloproteinase 2/metabolism , Cells, Cultured , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Epithelial-Mesenchymal Transition , Focal Adhesion Kinase 1/genetics , HCT116 Cells , Humans , Matrix Metalloproteinase 2/genetics , Neoplasm Metastasis , Proteome/genetics , Proteome/metabolism , Signal Transduction , Tetraspanin 29/genetics , Tetraspanin 29/metabolismABSTRACT
BACKGROUND: To compare the number of lymph nodes (LNs) detected when using Carnoy's solution (CS) versus 10% neutral buffered formalin (NBF) to fix specimens after radical gastrectomy for gastric cancer. PATIENTS AND METHODS: LNs were routinely detected using NBF until 2020, since then, for the fixation procedure, residual fat was fixed in CS for 24 hours and dissected again for the detection of further LNs. Of 143 specimens, 117 were included in the NBF group and 26 in the CS group. RESULTS: The mean numbers of LNs examined were 27.85±14.89 and 36.30±12.41 in the NBF and CS groups, respectively (p=0.008). The mean number of additional LNs detected using CS was 8.07±2.91, of which 0.38±1.02 were metastatic. Additional LNs were found in all patients of the CS group, and all were ≤3 mm. Of the 26 patients in the CS group, metastatic LNs were detected in four, disease in two of whom was up-staged. CONCLUSION: CS is an appropriate alternative to NBF for the fixation of gastric cancer specimens, and more LNs were detected in the resected specimens fixed when using CS compared with NBF.