Evaluation of viral infection as an etiology of ME/CFS: a systematic review and meta-analysis.

BACKGROUND: Myalgic encephalitis/chronic fatigue syndrome (ME/CFS) is a long-term disabling illness without a medically explained cause. Recently during COVID-19 pandemic, many studies have confirmed the symptoms similar to ME/CFS in the recovered individuals. To investigate the virus-related etiopathogenesis of ME/CFS, we conducted a systematic assessment of viral infection frequency in ME/CFS patients. METHODS: We conducted a comprehensive search of PubMed and the Cochrane Library from their inception through December 31, 2022, using selection criteria of viral infection prevalence in ME/CFS patients and controls. Subsequently, we performed a meta-analysis to assess the extent of viral infections' contribution to ME/CFS by comparing the odds ratio between ME/CFS patients and controls (healthy and/or diseased). RESULTS: Finally, 64 studies met our eligibility criteria regarding 18 species of viruses, including a total of 4971 ME/CFS patients and 9221 control subjects. The participants included healthy subjects and individuals with one of 10 diseases, such as multiple sclerosis or fibromyalgia. Two DNA viruses (human herpes virus (HHV)-7 and parvovirus B19, including their co-infection) and 3 RNA viruses (borna disease virus (BDV), enterovirus and coxsackie B virus) showed odds ratios greater than 2.0 compared with healthy and/or diseased subjects. Specifically, BDV exceeded the cutoff with an odds ratio of ≥ 3.47 (indicating a "moderate association" by Cohen's d test) compared to both healthy and diseased controls. CONCLUSION: This study comprehensively evaluated the risk of viral infections associated with ME/CFS, and identified BDV. These results provide valuable reference data for future studies investigating the role of viruses in the causation of ME/CFS.

Comparison of assessment scores for fatigue between multidimensional fatigue inventory (MFI-K) and modified chalder fatigue scale (mKCFQ).

BACKGROUND: Because of the absence of biological parameters for fatigue, appropriate instruments for assessing the degree of fatigue are important in the diagnosis and management of people complaining of fatigue-like symptoms. This study statistically analyzed the fatigue scores from two typical questionnaire-based instruments: the Korean version of the Multidimensional Fatigue Inventory (MFI-K) and the modified Chalder Fatigue Scale (mKCFQ). METHODS: Seventy participants (males n = 40, females n = 30, median age 48 years old, range of 25-67) were grouped into three groups ('mild' = 20, 'moderate' = 42, and 'severe' = 8) according to self-reported fatigue levels using a 7-point Likert scale. The similarities and differences between two instrument-derived scores were analyzed using correlations (r) and multidimensional scaling (MDS). RESULTS: The total scores of the two assessments were significantly correlated (r = 75%, p < 0.001), as were the subscores ('Total Physical fatigue': r = 76%, p < 0.001, 'Total Mental fatigue': r = 56%, p < 0.001). Relative overestimation of the MFI-K (45.8 ± 11.3) compared to the mKCFQ (36.1 ± 16.2) was observed, which was especially prominent in the 'mild' group. The scores of the three groups were more easily distinguished by the mKCFQ than by the MFI-K. In terms of the five dimension scores, we found a higher correlation of the two assessments for 'general fatigue' (r = 79%, p < 0.001) and 'physical fatigue' (r = 66%, p < 0.001) than for the reductions in 'motivation' (r = 41%, p < 0.01) and 'activity' (r = 26%, p > 0.05). CONCLUSIONS: Our results may indicate the usefulness of the two instruments, especially for the physical symptoms of fatigue ('general' and 'physical' fatigue). Furthermore, the MFI-K may be useful for conditions of moderate-to-severe fatigue, such as chronic fatigue syndrome, but the mKCFQ may be useful for all spectra of fatigue, including in subhealthy people.

Nationwide epidemiological characteristics of chronic fatigue syndrome in South Korea.

BACKGROUND: Chronic fatigue syndrome (CFS) is a long-term disabling illness accompanied by medically unexplained fatigue. This study aimed to explore the epidemiological characteristics of CFS in South Korea. METHODS: Using the nationwide medical records provided by the Korean Health Insurance Review & Assessment Service (HIRA), we analyzed the entire dataset for CFS patients diagnosed by physicians in South Korea from January 2010 to December 2020. RESULTS: The annual mean incidence of CFS was estimated to be 44.71 ± 6.10 cases per 100,000 individuals [95% CI: 40.57, 48.76], and the prevalence rate was 57.70 ± 12.20 cases per 100,000 individuals [95% CI: 49.40, 65.79]. These two rates increased by 1.53- and 1.94-fold from 2010 to 2020, respectively, and showed an increasing trend with aging and an approximately 1.5-fold female predominance. CONCLUSIONS: This study is the first to report the nationwide epidemiological features of CFS, which reflects the clinical reality of CFS diagnosis and care in South Korea. This study will be a valuable reference for studies of CFS in the future.

Review of case definitions for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

BACKGROUND: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating disease with unknown causes. From the perspectives on the etiology and pathophysiology, ME/CFS has been labeled differently, which influenced changes in case definitions and terminologies. This review sought to feature aspects of the history, developments, and differential symptoms in the case definitions. METHODS: A search was conducted through PubMed published to February 2020 using the following search keywords: case definition AND chronic fatigue syndrome [MeSH Terms]. All reference lists of the included studies were checked. Of the included studies, the number of citations and the visibility in the literatures of the definitions were considered for comparisons of the criteria. RESULTS: Since the first 'ME' case definition was developed in 1986, 25 case definitions/diagnostic criteria were created based on three conceptual factors (etiology, pathophysiology, and exclusionary disorders). These factors can be categorized into four categories (ME, ME/CFS, CFS, and SEID) and broadly characterized according to primary disorder (ME-viral, CFS-unknown, ME/CFS-inflammatory, SEID-multisystemic), compulsory symptoms (ME and ME/CFS-neuroinflammatory, CFS and SEID-fatigue and/or malaise), and required conditions (ME-infective agent, ME/CFS, CFS, SEID-symptoms associated with fatigue, e.g., duration of illness). ME and ME/CFS widely cover all symptom categories, while CFS mainly covers neurologic and neurocognitive symptoms. Fatigue, cognitive impairment, PEM, sleep disorder, and orthostatic intolerance were the overlapping symptoms of the 4 categories, which were included as SEID criteria. CONCLUSIONS: This study comprehensively described the journey of the development of case definitions and compared the symptom criteria. This review provides broader insights and explanations to understand the complexity of ME/CFS for clinicians and researchers.

Systematic review and meta-analysis of the prevalence of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME).

BACKGROUND: Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) has been emerging as a significant health issue worldwide. This study aimed to systemically assess the prevalence of CFS/ME in various aspects of analyses for precise assessment. METHODS: We systematically searched prevalence of CFS/ME from public databases from 1980 to December 2018. Data were extracted according to 7 categories for analysis: study participants, gender and age of the participants, case definition, diagnostic method, publication year, and country of the study conducted. Prevalence data were collected and counted individually for studies adopted various case definitions. We analyzed and estimated prevalence rates in various angles: average prevalence, pooled prevalence and meta-analysis of all studies. RESULTS: A total of 1291 articles were initially identified, and 45 articles (46 studies, 56 prevalence data) were selected for this study. Total 1085,976 participants were enrolled from community-based survey (540,901) and primary care sites (545,075). The total average prevalence was 1.40 ± 1.57%, pooled prevalence 0.39%, and meta-analysis 0.68% [95% CI 0.48-0.97]. The prevalence rates were varied by enrolled participants (gender, study participants, and population group), case definitions and diagnostic methods. For example, in the meta-analysis; women (1.36% [95% CI 0.48-0.97]) vs. men (0.86% [95% CI 0.48-0.97]), community-based samples (0.76% [95% CI 0.53-1.10]) vs. primary care sites (0.63% [95% CI 0.37-1.10]), adults ≥ 18 years (0.65% [95% CI 0.43-0.99]) vs. children and adolescents < 18 years (0.55% [95% CI 0.22-1.35]), CDC-1994 (0.89% [95% CI 0.60-1.33]) vs. Holmes (0.17% [95% CI 0.06-0.49]), and interviews (1.14% [95% CI 0.76-1.72]) vs. physician diagnosis (0.09% [95% CI 0.05-0.13]), respectively. CONCLUSIONS: This study comprehensively estimated the prevalence of CFS/ME; 0.89% according to the most commonly used case definition CDC-1994, with women approximately 1.5 to 2 folds higher than men in all categories. However, we observed the prevalence rates are widely varied particularly by case definitions and diagnostic methods. An objective diagnostic tool is urgently required for rigorous assessment of the prevalence of CFS/ME.

Ciprofloxacin Enhances TRAIL-Induced Apoptosis in Lung Cancer Cells by Upregulating the Expression and Protein Stability of Death Receptors through CHOP Expression.

Ciprofloxacin (CIP) is a potent antimicrobial agent with multiple effects on host cells and tissues. Previous studies have highlighted their proapoptotic effect on human cancer cells. The current study showed that subtoxic doses of CIP effectively sensitized multiple cancer cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. Although TRAIL alone mediated the partial proteolytic processing of procaspase-3 in lung cancer cells, co-treatment with CIP and TRAIL efficiently restored the complete activation of caspases. We found that treatment of lung cancer with CIP significantly upregulated the expression and protein stability of death receptor (DR) 5. These effects were mediated through the regulation of transcription factor CCAT enhancer-binding protein homologous protein (CHOP) since the silencing of these signaling molecules abrogated the effect of CIP. Taken together, these results indicated that the upregulation of death receptor expression and protein stability by CIP contributed to the restoration of TRAIL-sensitivity in lung cancer cells.

PINK1 positively regulates HDAC3 to suppress dopaminergic neuronal cell death.

Deciphering the molecular basis of neuronal cell death is a central issue in the etiology of neurodegenerative diseases, such as Parkinson's and Alzheimer's. Dysregulation of p53 levels has been implicated in neuronal apoptosis. The role of histone deacetylase 3 (HDAC3) in suppressing p53-dependent apoptosis has been recently emphasized; however, the molecular basis of modulation of p53 function by HDAC3 remains unclear. Here we show that PTEN-induced putative kinase 1 (PINK1), which is linked to autosomal recessive early-onset familial Parkinson's disease, phosphorylates HDAC3 at Ser-424 to enhance its HDAC activity in a neural cell-specific manner. PINK1 prevents H2O2-induced C-terminal cleavage of HDAC3 via phosphorylation of HDAC3 at Ser-424, which is reversed by protein phosphatase 4c. PINK1-mediated phosphorylation of HDAC3 enhances its direct association with p53 and causes subsequent hypoacetylation of p53. Genetic deletion of PINK1 partly impaired the suppressive role of HDAC3 in regulating p53 acetylation and transcriptional activity. However, depletion of HDAC3 fully abolished the PINK1-mediated p53 inhibitory loop. Finally, ectopic expression of phosphomometic-HDAC3(S424E) substantially overcomes the defective action of PINK1 against oxidative stress in dopaminergic neuronal cells. Together, our results uncovered a mechanism by which PINK1-HDAC3 network mediates p53 inhibitory loop in response to oxidative stress-induced damage.

Tunicamycin promotes apoptosis in leukemia cells through ROS generation and downregulation of survivin expression.

Tunicamycin (TN), one of the endoplasmic reticulum stress inducers, has been reported to inhibit tumor cell growth and exhibit anticarcinogenic activity. However, the mechanism by which TN initiates apoptosis remains poorly understood. In the present study, we investigated the effect of TN on the apoptotic pathway in U937 cells. We show that TN induces apoptosis in association with caspase-3 activation, generation of reactive oxygen species (ROS), and downregulation of survivin expression. P38 MAPK (mitogen-activated protein kinase) and the generation of ROS signaling pathway play crucial roles in TN-induced apoptosis in U937 cells. We hypothesized that TN-induced activation of p38 MAPK signaling pathway is responsible for cell death. To test this hypothesis, we selectively inhibited MAPK during treatment with TN. Our data demonstrated that inhibitor of p38 (SB), but not ERK (PD) or JNK (SP), partially maintained apoptosis during treatment with TN. Pre-treatment with NAC and GSH markedly prevented cell death, suggesting a role for ROS in this process. Ectopic expression of survivin in U937 cells attenuated TN-induced apoptosis by suppression of caspase-3 cleavage, mitochondrial membrane potential, and cytochrome c release in U937 cells. Taken together, our results show that TN modulates multiple components of the apoptotic response of human leukemia cells and raise the possibility of a novel therapeutic strategy for hematological malignancies.

MiR-223 deficiency increases eosinophil progenitor proliferation.

Recently, microRNAs have been shown to be involved in hematopoietic cell development, but their role in eosinophilopoiesis has not yet been described. In this article, we show that miR-223 is upregulated during eosinophil differentiation in an ex vivo bone marrow-derived eosinophil culture system. Targeted ablation of miR-223 leads to an increased proliferation of eosinophil progenitors. We found upregulation of a miR-223 target gene, IGF1R, in the eosinophil progenitor cultures derived from miR-223(-/-) mice compared with miR-223(+/+) littermate controls. The increased proliferation of miR-223(-/-) eosinophil progenitors was reversed by treatment with an IGF1R inhibitor (picropodophyllin). Whole-genome microarray analysis of differentially regulated genes between miR-223(+/+) and miR-223(-/-) eosinophil progenitor cultures identified a specific enrichment in genes that regulate hematologic cell development. Indeed, miR-223(-/-) eosinophil progenitors had a delay in differentiation. Our results demonstrate that microRNAs regulate the development of eosinophils by influencing eosinophil progenitor growth and differentiation and identify a contributory role for miR-223 in this process.

An alginate-like exopolysaccharide biosynthesis gene cluster involved in biofilm aerial structure formation by Pseudomonas alkylphenolia.

Pseudomonas alkylphenolia is known to form different types of multicellular structures depending on the environmental stimuli. Aerial structures formed during vapor p-cresol utilization are unique. Transposon mutants that showed a smooth colony phenotype failed to form a differentiated biofilm, including aerial structures and pellicles, and showed deficient surface spreading motility. The transposon insertion sites were located to a gene cluster designated epm (extracellular polymer matrix), which comprises 11 ORFs in the same transcriptional orientation. The putative proteins encoded by the genes in the epm cluster showed amino acid sequence homology to those found in the alginate biosynthesis gene clusters, e.g., in Pseudomonas aeruginosa at similarity levels of 32.3-86.4 %. This overall resemblance indicated that the epm gene cluster encodes proteins that mediate the synthesis of an exopolysaccharide composed of uronic acid(s) similar to alginate. Our preliminary results suggested that the epm-derived polymer is a substituted polymannuronic acid. Gene clusters homologous to the epm gene cluster are found in the genomes of a few species of the genera Pseudomonas, Alcanivorax, and Marinobacter. A mutational analysis showed that the epmJ and epmG genes encoding putative exopolysaccharide-modifying enzymes are required to form multicellular structures. An analysis of the activity of the promoter P epmD using a transcriptional fusion to the green fluorescence protein gene showed that the epm genes are strongly expressed at the tips of the specialized aerial structures. Our results suggested that the epm gene cluster is involved in the formation of a scaffold polysaccharide that is required to form multicellular structures in P. alkylphenolia.

Drug Response of Patient-Derived Lung Cancer Cells Predicts Clinical Outcomes of Targeted Therapy.

Intratumor heterogeneity leads to different responses to targeted therapies, even within patients whose tumors harbor identical driver oncogenes. This study examined clinical outcomes according to a patient-derived cell (PDC)-based drug sensitivity test in lung cancer patients treated with targeted therapies. From 487 lung cancers, 397 PDCs were established with a success rate of 82%. In 139 PDCs from advanced non-small-cell lung cancer (NSCLC) patients receiving targeted therapies, the standardized area under the curve (AUC) values for the drugs was significantly correlated with their tumor response (p = 0.002). Among 59 chemo-naive EGFR/ALK-positive NSCLC patients, the PDC non-responders showed a significantly inferior response rate (RR) and progression-free survival (PFS) for the targeted drugs than the PDC responders (RR, 25% vs. 78%, p = 0.011; median PFS, 3.4 months [95% confidence interval (CI), 2.8-4.1] vs. 11.8 months [95% CI, 6.5-17.0], p < 0.001). Of 25 EGFR-positive NSCLC patients re-challenged with EGFR inhibitors, the PDC responder showed a higher RR than the PDC non-responder (42% vs. 15%). Four patients with wild-type EGFR or uncommon EGFR-mutant NSCLC were treated with EGFR inhibitors based on their favorable PDC response to EGFR inhibitors, and two patients showed dramatic responses. Therefore, the PDC-based drug sensitivity test results were significantly associated with clinical outcomes in patients with EGFR- or ALK-positive NSCLC. It may be helpful for predicting individual heterogenous clinical outcomes beyond genomic alterations.

MicroRNA-21 limits in vivo immune response-mediated activation of the IL-12/IFN-gamma pathway, Th1 polarization, and the severity of delayed-type hypersensitivity.

An altered balance between Th1 and Th2 cytokines is responsible for a variety of immunoinflammatory disorders such as asthma, yet the role of posttranscriptional mechanisms, such as those mediated by microRNAs (miRs), in adjusting the relative magnitude and balance of Th cytokine expression have been largely unexplored. In this study, we show that miR-21 has a central role in setting a balance between Th1 and Th2 responses to Ags. Targeted ablation of miR-21 in mice led to reduced lung eosinophilia after allergen challenge, with a broadly reprogrammed immunoactivation transcriptome and significantly increased levels of the Th1 cytokine IFN-γ. Biological network-based transcriptome analysis of OVA-challenged miR-21(-/-) mice identified an unexpected prominent dysregulation of IL-12/IFN-γ pathways as the most significantly affected in the lungs, with a key role for miR-21 in IFN-γ signaling and T cell polarization, consistent with a functional miR-21 binding site in IL-12p35. In support of these hypotheses, miR-21 deficiency led dendritic cells to produce more IL-12 after LPS stimulation and OVA-challenged CD4(+) T lymphocytes to produce increased IFN-γ and decreased IL-4. Further, loss of miR-21 significantly enhanced the Th1-associated delayed-type hypersensitivity cutaneous responses. Thus, our results define miR-21 as a major regulator of Th1 versus Th2 responses, defining a new mechanism for regulating polarized immunoinflammatory responses.

A Randomized Phase II Study of Irinotecan Plus Cisplatin with or without Simvastatin in Ever-Smokers with Extended Disease Small Cell Lung Cancer.

PURPOSE: This study evaluated whether an addition of simvastatin to chemotherapy improves survival in ever-smokers with extensive disease (ED)-small cell lung cancer (SCLC). Materials and Methods: This is an open-label randomized phase II study conducted in National Cancer Center (Goyang, Korea). Chemonaive patients with ED-SCLC, smoking history (≥ 100 cigarettes lifetime), and Eastern Cooperative Oncology Group performance status of ≤ 2 were eligible. Patients were randomized to receive irinotecan plus cisplatin alone or with simvastatin (40 mg once daily orally) for a maximum of six cycles. Primary endpoint was the the 1-year survival rate. RESULTS: Between September 16, 2011, and September 9, 2021, 125 patients were randomly assigned to the simvastatin (n=62) or control (n=63) groups. The median smoking pack year was 40 years. There was no significant difference in the 1-year survival rate between the simvastatin and control groups (53.2% vs. 58.7%, p=0.535). The median progression-free survival and overall survival between the simvastatin arm vs. the control groups were 6.3 months vs. 6.4 months (p=0.686), and 14.4 months vs. 15.2 months, respectively (p=0.749). The incidence of grade 3-4 adverse events was 62.9% in the simvastatin group and 61.9% in the control group. In the exploratory analysis of lipid profiles, patients with hypertriglyceridemia had significantly higher 1-year survival rates than those with normal triglyceride levels (80.0% vs. 52.7%, p=0.046). CONCLUSION: Addition of simvastatin to chemotherapy provided no survival benefit in ever-smokers with ED-SCLC. Hypertriglyceridemia may be associated with better prognosis in these patient population.

Epigenetic regulation of the IL-13-induced human eotaxin-3 gene by CREB-binding protein-mediated histone 3 acetylation.

The etiology of a variety of chronic inflammatory disorders has been attributed to the interaction of genetic and environmental factors. Herein, we identified a link between epigenetic regulation and IL-13-driven eotaxin-3 in the pathogenesis of chronic allergic inflammation. We first demonstrated that the cAMP-responsive element (CRE) site in the eotaxin-3 promoter affects IL-13-induced eotaxin-3 promoter activity. Furthermore, the CRE-binding protein-binding protein (CBP), a histone acetyltransferase, induced base-line and IL-13-induced eotaxin-3 promoter activity. Additionally, IL-13 treatment promoted global histone 3 acetylation as well as the formation of a complex containing CBP and STAT6 and the subsequent acetylation of histone 3 at the eotaxin-3 promoter. CBP gene silencing decreased IL-13-induced transcription of eotaxin-3. Conversely, inhibition of histone deacetylation increased IL-13-induced eotaxin-3 production. Clinical studies demonstrated markedly increased global acetylation of histone 3 in the inflamed tissue of patients with allergic inflammation. Collectively, these results identify an epigenetic mechanism involving CBP and chromatin remodeling in regulating IL-13-induced chemokine transcription.

Incidence Rate of Bee Venom Acupuncture Related Anaphylaxis: A Systematic Review.

BACKGROUND: Bee venom acupuncture (BVA) is an effective treatment method for various diseases. Bee venom, however, can cause adverse effects, even rarely including life-threatening anaphylaxis, so safety-related evidence is required. In this study, we systematically estimated the incidence rate of anaphylaxis in response to BVA. METHODS: We searched eight databases (MEDLINE (Pubmed), EMBASE, Cochrane Central Register of Controlled, KISS, KMBASE, Koreamed, OASIS, and NDSL) and systematically reviewed the articles that met the inclusion/exclusion criteria. RESULTS: Among 225 potentially relevant articles, 49 were selected for this study. The overall incidence rate of anaphylaxis in response to BVA was 0.045% (95% CI 0.028-0.062). Women (0.083%, 95% CI 0.010-0.157) showed a higher incidence rate than men (0.019%, 95% CI -0.018 to 0.055), while the incidence for patients who had a skin test conducted (0.041%, 95% CI 0.011-0.072) was not significantly different compared to that obtained for patients for which there was no information about a skin test (0.047%, 95% CI 0.026-0.067). The publication year affected the incidence rate: it was highest before 1999 (1.099%, 95% CI -1.043 to 3.241), lower between 2000 and 2009 (0.049%, 95% CI 0.025-0.073), and lowest between 2010 and 2021 (0.037% 95% CI 0.014-0.060). CONCLUSIONS: In this study, we provide reference data about risk size and factors of BVA-related anaphylaxis, which is essentially required for BVA application in clinics.

Prevalence of Chronic Fatigue Syndrome (CFS) in Korea and Japan: A Meta-Analysis.

BACKGROUND: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a long-term disabling illness accompanied by fatigue unsolved by rest. However, ME/CFS is a poorly understood illness that lacks a universally accepted pathophysiology and treatment. A lack of CFS-related studies have been conducted in Asian countries. This study aimed to estimate and compare the prevalence of ME/CFS in Korea and Japan and conducted a meta-analysis. METHODS: We searched PubMed, EMBASE, Cochrane, and KMBASE for population-based prevalence studies of the two countries and synthesized the data according to the Fukuda case definition. RESULTS: Of the eight studies (five in Korea, three in Japan) included, the total prevalence rate of Korean studies was 0.77% (95% CI 0.34-1.76), and 0.76% (95% CI 0.46-1.25) for the Japanese studies. The prevalence rate in females was approximately two-fold higher than males in Korean studies (1.31% female vs. 0.60% male), while the gender difference was less obvious in Japanese studies (0.76% female vs. 0.65% male). CONCLUSIONS: Further epidemiology studies on the female ME/CFS prevalence rate between countries may be required.

The Prospects of the Two-Day Cardiopulmonary Exercise Test (CPET) in ME/CFS Patients: A Meta-Analysis.

BACKGROUND: The diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is problematic due to the lack of established objective measurements. Postexertional malaise (PEM) is a hallmark of ME/CFS, and the two-day cardiopulmonary exercise test (CPET) has been tested as a tool to assess functional impairment in ME/CFS patients. This study aimed to estimate the potential of the CPET. METHODS: We reviewed studies of the two-day CPET and meta-analyzed the differences between ME/CFS patients and controls regarding four parameters: volume of oxygen consumption and level of workload at peak (VO2peak, Workloadpeak) and at ventilatory threshold (VO2@VT, Workload@VT). RESULTS: The overall mean values of all parameters were lower on the 2nd day of the CPET than the 1st in ME/CFS patients, while it increased in the controls. From the meta-analysis, the difference between patients and controls was highly significant at Workload@VT (overall mean: -10.8 at Test 1 vs. -33.0 at Test 2, p < 0.05), which may reflect present the functional impairment associated with PEM. CONCLUSIONS: Our results show the potential of the two-day CPET to serve as an objective assessment of PEM in ME/CFS patients. Further clinical trials are required to validate this tool compared to other fatigue-inducing disorders, including depression, using well-designed large-scale studies.

Formation of specialized aerial architectures by Rhodococcus during utilization of vaporized p-cresol.

When grown with vaporized alkylphenols such as p-cresol as the sole carbon and energy source, several isolated Rhodococcus strains formed growth structures like miniature mushrooms, termed here specialized aerial architectures (SAA), that reached sizes of up to 0.8 mm in height. Microscopic examination allowed us to view the distinct developmental stages during the formation of SAA from a selected strain, Rhodococcus sp. KL96. Initially, mounds consisting of long rod cells arose from a lawn of cells, and then highly branched structures were formed from the mounds. During the secondary stage of development, branching began after long rod cells grew outward and twisted longitudinally, serving as growth points, and the cells at the base of the mound became short rods that supported upward growth. Cells in the highly fluffy structures were eventually converted, via reductive division, into structures that resembled cocci, with a diameter of approximately 0.5 microm, that were arranged in chains. Most cells inside the SAA underwent a phase variation in order to form wrinkled colonies from cells that originally formed smooth colonies. Approximately 2 months was needed for complete development of the SAA, and viable cells were recovered from SAA that were incubated for more than a year. An extracellular polymeric matrix layer and lipid bodies appeared to play an important role in structural integrity and as a metabolic energy source, respectively. To our knowledge, similar formation of aerial structures for the purpose of substrate utilization has not been reported previously for Gram-positive bacteria.

Genetic polymorphism and haplotype analysis of 4 tightly linked X-STR duos in Koreans.

AIM: To investigate genetic polymorphism and haplotypes of tightly linked X-chromosomal short tandem repeat (X-STR) clusters in Koreans. METHODS: Four X-STR duos in the linkage group 1-4 (DXS10135-DXS8378, DXS7132-DXS10074, HPRTB-DXS10101, and DXS10134-DXS7423) were investigated in 450 unrelated Koreans (300 men and 150 women) using the Mentype Argus X-8 Polymerase Chain Reaction Amplification Kit. RESULTS: No significant deviation from Hardy-Weinberg equilibrium was observed in any of the 8 loci. DXS10135 was the most polymorphic X-STRs, with 25 alleles and DXS7423 was the least informative, with 5 alleles. Eleven off-ladder alleles and a triallelic pattern were observed, and these alleles were characterized by cloning and sequencing analysis. In 300 Korean men, 38 to 59 haplotypes were observed for each linkage duo with 91.6-96.6% of haplotype diversities. However, due to the low genetic diversity of DXS7423, the X-STR duo in linkage group 4 (DXS10134-DXS7423), in comparison with other linkage duos, had considerably lower haplotype diversity values (91.6%) with 3 common haplotypes (35-15, 36-15, and 37-15) observed in 44.3% of Koreans. CONCLUSION: Four X-STR duos in the linkage group 1-4 will be able to provide a powerful tool for solving complex kinship cases in Koreans. However, to increase the haplotype diversity in the linkage group 4, it will be useful to discover a new marker for Asians that can serve as an adequate substitute for DXS7423 or at least complement the existing linkage duo of DXS10134-DXS7423.

IL-27 enhances IL-15/IL-18-mediated activation of human natural killer cells.

BACKGROUND: Natural killer (NK) cells are an emerging new tool for cancer immunotherapy. To develop NK cell therapeutics from peripheral blood mononuclear cells (PBMCs) of healthy donors, substantial expansion of primary NK cells is necessary because of the very low number of these cells in peripheral blood. In this study, we aimed to investigate the effect of various cytokine alone or combinations, in expanded NK cells and to analyze the synergetic effect of cytokine combinations. METHODS: Human NK cells were isolated from healthy donor PBMC. Purified NK cells were stimulated with single cytokines or combinations of IL-2, IL-15, IL-18, and IL-27. The expanded NK cells were characterized by flow cytometry, cytotoxicity assay, calcein AM assay and Western blot. RESULTS: We investigated the synergistic effects of each cytokine, namely, IL-2, IL-15, IL-18, and IL-27, on human NK cells isolated from PBMCs of healthy donors and cultured for 21 days. We identified that IL-15/IL-18/IL-27-mediated activation of NK cells most potently increased NK cell proliferation, cytotoxicity, and IFN-É£ secretion compared with the activation observed with other treatments, including IL-2, IL-15, and IL-15/IL-18. Additionally, the expression of DNAM-1, NKG2D, CD69, and natural cytotoxicity receptors (NCRs; NKp30 and NKp44) increased on day 21 compared to that on day 0, demonstrating the activation of NK cells. In vitro, expanded NK cells were highly cytotoxic against cancer cells, displaying increased perforin and granzyme B accumulation. CONCLUSIONS: Taken together, these results indicated that IL-27 can synergize on NK cell expansion and activation with IL-15 and IL-18. In addition, we described an improved culture method for ex vivo expansion of human NK cells with IL-15/IL-18/IL-27 stimulation and characterized the response of NK cells to this stimulation.