ABSTRACT
BACKGROUND: Identifying the DNA-binding specificities of transcription factors (TF) is central to understanding gene networks that regulate growth and development. Such knowledge is lacking in oomycetes, a microbial eukaryotic lineage within the stramenopile group. Oomycetes include many important plant and animal pathogens such as the potato and tomato blight agent Phytophthora infestans, which is a tractable model for studying life-stage differentiation within the group. RESULTS: Mining of the P. infestans genome identified 197 genes encoding proteins belonging to 22 TF families. Their chromosomal distribution was consistent with family expansions through unequal crossing-over, which were likely ancient since each family had similar sizes in most oomycetes. Most TFs exhibited dynamic changes in RNA levels through the P. infestans life cycle. The DNA-binding preferences of 123 proteins were assayed using protein-binding oligonucleotide microarrays, which succeeded with 73 proteins from 14 families. Binding sites predicted for representatives of the families were validated by electrophoretic mobility shift or chromatin immunoprecipitation assays. Consistent with the substantial evolutionary distance of oomycetes from traditional model organisms, only a subset of the DNA-binding preferences resembled those of human or plant orthologs. Phylogenetic analyses of the TF families within P. infestans often discriminated clades with canonical and novel DNA targets. Paralogs with similar binding preferences frequently had distinct patterns of expression suggestive of functional divergence. TFs were predicted to either drive life stage-specific expression or serve as general activators based on the representation of their binding sites within total or developmentally-regulated promoters. This projection was confirmed for one TF using synthetic and mutated promoters fused to reporter genes in vivo. CONCLUSIONS: We established a large dataset of binding specificities for P. infestans TFs, representing the first in the stramenopile group. This resource provides a basis for understanding transcriptional regulation by linking TFs with their targets, which should help delineate the molecular components of processes such as sporulation and host infection. Our work also yielded insight into TF evolution during the eukaryotic radiation, revealing both functional conservation as well as diversification across kingdoms.
Subject(s)
Evolution, Molecular , Phylogeny , Phytophthora infestans , Transcription Factors , Phytophthora infestans/genetics , Phytophthora infestans/metabolism , Transcription Factors/metabolism , Transcription Factors/genetics , Binding Sites , Protein BindingABSTRACT
OBJECTIVE: Prognostic models proposed for cirrhotic patients' survival have not been satisfactorily investigated in the Vietnam population, especially in the medium-term period. PATIENTS AND METHODS: In this prospective study, we enrolled a total of 904 patients admitted to Hepato-Gastroenterology Center, Bach Mai Hospital from December 2019 to November 2021 and calculated their CP, MELD, MELD-Na score, IMELD, Refit MELD, and Refit MELD-Na after 2-year follow-up to compare their survival prognosis. RESULTS: The mean age of the patients was 53.8 ±10.8 years, and males constituted 91%. Compared with the surviving group, deceased patients had statistically significant lower albumin, higher INR, serum bilirubin, and creatinine levels with higher means of all prognostic scores. RefitMELD score had the highest AUC (0.768), followed by MELD (0.766), and the lowest belonged to RefitMELDNa (0.669). CONCLUSIONS: In conclusion, deceased patients had significantly higher values of Child-Pugh score and all MELD-based scores than survival. RefitMELD is the most reliable scoring system to predict 2-year mortality in patients with decompensated liver cirrhosis.
Subject(s)
Liver Cirrhosis , Sodium , Male , Humans , Adult , Middle Aged , Prognosis , Prospective Studies , Severity of Illness Index , ROC Curve , Retrospective StudiesABSTRACT
BACKGROUND: TB control remains a serious public health problem, compounded by poor treatment adherence, which increases the likelihood of onward transmission. We evaluated the effectiveness of medication event reminder monitoring (MERM) upon treatment adherence in a high TB burden setting.METHODS: We conducted an open-label parallel group randomised controlled trial among pulmonary TB adults. Participants were provided with a MERM device to store their medications. In the intervention arm, the devices were set to provide daily medication intake reminders. Primary outcome was the proportion of patient-months in which at least 6/30 doses were missed. Secondary outcomes included 1) the proportion of patient-months in which at least 14/30 doses were missed, and 2) the proportion of doses missed.RESULTS: Of 2,142 patients screened, 798 (37.3%) met the inclusion criteria and 250 participants were enrolled. The mean ratio (MR) for poor adherence between the intervention and control groups was 0.72 (95% CI 0.55-0.86). The intervention was also associated with a reduction in the proportion of patients missing at least 14/30 doses (MR 0.61, 95% CI 0.54-0.68) and the percentage of total doses missed (MR 0.75, 95% CI 0.68-0.80).CONCLUSION: MERM is effective in improving TB treatment adherence in a resource-limited environment.
Subject(s)
Medication Adherence , Tuberculosis, Pulmonary , Adult , Humans , Reminder Systems , Tuberculosis, Pulmonary/drug therapy , Drug MonitoringABSTRACT
Tumor invasion is likely driven by the product of intrinsic and extrinsic stresses, reduced intercellular adhesion, and reciprocal interactions between the cancer cells and the extracellular matrix (ECM). The ECM is a dynamic material system that is continuously evolving with the tumor microenvironment. Although it is widely reported that cancer cells degrade the ECM to create paths for migration using membrane-bound and soluble enzymes, other nonenzymatic mechanisms of invasion are less studied and not clearly understood. To explore tumor invasion that is independent of enzymatic degradation, we have created an open three-dimensional (3D) microchannel network using a novel bioconjugated liquid-like solid (LLS) medium to mimic both the tortuosity and the permeability of a loose capillary-like network. The LLS is made from an ensemble of soft granular microgels, which provides an accessible platform to investigate the 3D invasion of glioblastoma (GBM) tumor spheroids using in situ scanning confocal microscopy. The surface conjugation of the LLS microgels with type 1 collagen (COL1-LLS) enables cell adhesion and migration. In this model, invasive fronts of the GBM microtumor protruded into the proximal interstitial space and may have locally reorganized the surrounding COL1-LLS. Characterization of the invasive paths revealed a super-diffusive behavior of these fronts. Numerical simulations suggest that the interstitial space guided tumor invasion by restricting available paths, and this physical restriction is responsible for the super-diffusive behavior. This study also presents evidence that cancer cells utilize anchorage-dependent migration to explore their surroundings, and geometrical cues guide 3D tumor invasion along the accessible paths independent of proteolytic ability.
Subject(s)
Microgels , Humans , Cell Movement , Neoplasm Invasiveness/pathology , Extracellular Matrix/metabolism , Collagen Type I , Cell Line, Tumor , Tumor MicroenvironmentABSTRACT
BACKGROUND: In 2016, the Vietnamese Ministry of Health promoted development of antimicrobial stewardship for hospitals. AIM: To evaluate the effectiveness and safety of the enhanced antibiotic stewardship programme (ASP) compared to the original ASP among paediatric patients at a tertiary hospital for infectious diseases in Vietnam. METHODS: An interrupted time-series analysis was conducted to examine antibiotic use in paediatric patients aged 0-17 years admitted to the Hospital for Tropical Diseases in Ho Chi Minh City from April 2016 to March 2020. Outcomes measured were defined daily doses (DDDs) per 1000 patient-days; antibiotic days of therapy (DOT) per 1000 patient-days; percentage of antibiotic use by the World Health Organization Access, Watch, and Reserve (AWaRe) system; Access-to-Watch ratio; and worse clinical outcomes at discharge. FINDINGS: Of 60,172 admissions during the study period, 28,019 received at least one antibiotic (46.6%) during hospital stay. The Watch antibiotics were the most frequently prescribed (78.1% of total antibiotic courses). The enhanced ASP did not improve antibiotic prescribing by DDDs per 1000 patient-days (risk ratio: 1.05; 95% confidence interval: 0.94-1.17) and DOT per 1000 patient-days (1.11; 0.99-1.25) compared to the original ASP. However, the percentage of Access antibiotics prescribed, and the Access-to-Watch ratio increased after the enhanced ASP (1.73; 1.38-2.17). There was no significant difference in worse clinical outcomes at discharge between the original and enhanced ASP (1.25; 0.78-2.00). CONCLUSION: The enhanced ASP had modest impact on antibiotic consumption in the paediatric population despite the improvement of Access antibiotic use and the Access-to-Watch ratio.
Subject(s)
Antimicrobial Stewardship , Cross Infection , Anti-Bacterial Agents/therapeutic use , Child , Cross Infection/drug therapy , Humans , Tertiary Care Centers , VietnamABSTRACT
Policy must address drivers, not just symptoms, of subsidence.
ABSTRACT
INTRODUCTION: Current research is elucidating how the addition of depth of invasion (DOI) to the 8th edition of the American Joint Committee on Cancer (AJCC) TNM staging for oral cavity squamous cell carcinoma influences its prognostic accuracy. However, there is limited research on survival in pT3N0M0 oral tongue SCC (OTSCC) patients when stratifying by DOI. OBJECTIVES: Determine 5-year overall survival (OS), and cancer-specific survival (CSS) for patients with pT3N0M0 oral OTSCC based on shallow DOI (<10 mm) and deep DOI (10-20 mm). METHODS: Retrospective review involving three tertiary care cancer centers in North America. cT3N0M0 OTSCC patients receiving primary surgical treatment from 2004 to 2018 were identified. Inclusion: age > 18 years old and confirmation of pT3N0M0 OTSCC on surgical pathology. Exclusion: patients undergoing palliative treatment or previous head and neck surgery/radiotherapy. Analysis comprised two groups: shallow pT3 (tumor diameter > 4 cm, DOI < 10 mm) and deep pT3 (DOI 10 mm-20 mm). RESULTS: One hundred and four patients with pT3N0M0 OTSCC were included. Mean age was 59.1 years (range: 18-80.74). Age, gender, and Charlson Comorbidity Index were similar between the two groups (p > 0.05). Recurrence, LVI, PNI, and positive margins were more common in deep T3 tumors (P < 0.05). 5-year OS (50% vs 26%, p = 0.006) and CSS (72% vs 24%, p = 0.005) were worse in deep pT3 tumors. Deep pT3 disease was an independent predictor of OS (p = 0.004) and CSS (p = 0.01) on Cox-Regression analysis. CONCLUSION: DOI is an independent predictor of poor survival in pT3N0M0 OTSCC patients. Consideration should be given to escalating adjuvant therapy for deep pT3N0M0 OTSCC patients.
Subject(s)
Squamous Cell Carcinoma of Head and Neck , Tongue Neoplasms , Adult , Humans , Middle Aged , Neoplasm Invasiveness , Retrospective Studies , Survival Rate , Tongue Neoplasms/surgeryABSTRACT
Colistin is one of the antibiotics of last resort for human health. However, the dissemination of the plasmid-mediated colistin resistance gene mcr-1 is of great concern globally. In the One Health framework, the environment is an important component for managing antimicrobial resistance. However, little information is available concerning the prevalence of mcr-1 in water environments. We aimed to reveal the prevalence of mcr-1 in different water environments in Hanoi, Vietnam. Quantitative PCR was applied to detect mcr-1 in four urban drainages receiving untreated domestic wastewater, three rivers, five lakes and two groundwater samples. Urban drainages contained higher concentrations of mcr-1, suggesting that urban residents carry the gene. The class 1 integron-integrase gene was identified as a good surrogate of antibiotic resistance genes including mcr-1. A significant correlation was found between the levels of mcr-1 and the human-specific cross-assembly phage, which is an indicator of human faecal pollution. These results indicated that the primary source of mcr-1 in urban water environments is human faeces, which is consistent with the fact that most domestic wastewater is untreated in Hanoi. The control of untreated wastewater is critical for alleviating the spread of mcr-1 in water environments in Vietnam.
Subject(s)
Anti-Bacterial Agents/pharmacology , Colistin/pharmacology , Drug Resistance, Bacterial/genetics , Escherichia coli Proteins/genetics , Escherichia coli/genetics , Escherichia coli/drug effects , Escherichia coli Proteins/metabolism , Feces/microbiology , Humans , Lakes/microbiology , Plasmids/genetics , Rivers/microbiology , Vietnam , Wastewater/microbiologyABSTRACT
The thermal excitation, regulation, and detection of charge carriers in solid-state electronics have attracted great attention toward high-performance sensing applications but still face major challenges. Manipulating thermal excitation and transport of charge carriers in nanoheterostructures, we report a giant temperature sensing effect in semiconductor nanofilms via optoelectronic coupling, termed optothermotronics. A gradient of charge carriers in the nanofilms under nonuniform light illumination is coupled with an electric tuning current to enhance the performance of the thermal sensing effect. As a proof of concept, we used silicon carbide (SiC) nanofilms that form nanoheterostructures on silicon (Si). The sensing performance based on the thermal excitation of charge carriers in SiC is enhanced by at least 100 times through photon excitation, with a giant temperature coefficient of resistance (TCR) of up to -50%/K. Our findings could be used to substantially enhance the thermal sensing performance of solid-state electronics beyond the present sensing technologies.
ABSTRACT
BACKGROUND: Cryopreservation of zona pellucida (ZP)-free embryos provides more options for somatic cell nuclear transfer, particularly during handmade cloning. OBJECTIVE: This study investigated whether the removal of the ZP affects the development of porcine zygotes after vitrification and warming. MATERIALS AND METHODS: We determined the appropriate volume of the corresponding medium for the individual culture of ZP-intact and -free embryos and evaluated the protection effect of ZP during cryopreservation on the resulting development of the vitrified-warmed zygotes. RESULTS: The volume of culture medium influenced the development of ZP-intact zygotes, and a volume of 15 µL was most suitable for their development. However, the volume of culture medium did not modify the development of ZP-free zygotes. The removal of the ZP before vitrification did not adversely affect embryonic development or quality of the resulting blastocysts. CONCLUSION: Our results suggest that the removal of the ZP does not cause detrimental effects to the development of vitrified-warmed zygotes.
Subject(s)
Cryopreservation , Vitrification , Zona Pellucida , Zygote , Animals , Blastocyst , Female , Pregnancy , SwineABSTRACT
PURPOSE: For people with metabolic syndrome (MetS), altering the macronutrient composition of their diets might ameliorate metabolic abnormalities. The common method of clinical assessment only measures total lipid concentrations but ignores the individual species that contribute to these total concentrations. Thus, to predict the amelioration of MetS following caloric restriction (CR) and the intake of fish oil, we used lipidomics to investigate changes in plasma lipids and identify potential lipid metabolites. METHODS: Lipidomics was performed using ultra-high-performance liquid chromatography-tandem mass spectrometry on plasma samples from a clinical trial conducted over 12 weeks. Subjects were randomized into two groups: CR (n = 12) and CR with fish oil (CRF, n = 9). Anthropometric and clinical parameters were measured and correlated with plasma lipidomics data. RESULTS: Compared with baseline, significant differences were observed in body weight, waist circumference, blood pressure and interleukin-6 in both groups, but triglyceride (TG) levels significantly decreased in only the CRF group (all p < 0.05). A total of 138 lipid species were identified. Levels of species containing long-chain polyunsaturated fatty acids were significantly elevated-greater than twofold-following fish oil intake, these included TG (60:9) and phosphatidylcholine (p40:6) (all q < 0.05). TG (60:9) tended to correlate negatively with body weight, body mass index, blood pressure, and HbA1c following fish oil intake. CONCLUSION: CR and fish oil can ameliorate MetS features, including anthropometric parameters, blood pressure, and blood lipid concentrations. The levels of particular lipid species such as TG-containing docosapentaenoic acid were elevated post-intervention and negatively associated with MetS features. TG (60:9) may be proposed as a lipid metabolite to predict amelioration in MetS following the intake of CR and fish oil.
Subject(s)
Caloric Restriction , Diet , Fatty Acids, Omega-3 , Lipidomics , Metabolic Syndrome/complications , Metabolic Syndrome/diet therapy , Obesity/complications , Obesity/diet therapy , Adult , Fatty Acids, Omega-3/pharmacology , Fatty Acids, Omega-3/therapeutic use , Fish Oils/pharmacology , Fish Oils/therapeutic use , Humans , Male , Metabolic Syndrome/blood , Middle Aged , Obesity/bloodABSTRACT
Dupilumab is the first biologic registered for the treatment of atopic dermatitis (AD). We report on seven patients with AD presenting with a paradoxical head and neck erythema that appeared 10-39 weeks after the start of dupilumab treatment. The patients presented with a relatively sharply demarcated, patchy erythema in the head and neck area that showed no or less scaling compared with their usual eczema. Only one patient experienced symptoms of itch and burning, although this was notably different from his pre-existent facial AD. Except for a notable 'red face', eczema on other body parts had greatly improved in six of the seven patients, with a mean numerical rating scale for treatment satisfaction of 9 out of 10 at the time of biopsy. Treatment of the erythema with topical and systemic drugs was unsuccessful. Despite the presence of this erythema, none of our patients discontinued dupilumab treatment. Lesional skin biopsies showed an increased number of ectatic capillaries, and a perivascular lymphohistiocytic infiltration in all patients. In addition, epidermal hyperplasia with elongation of the rete ridges was observed in four patients, resembling a psoriasiform dermatitis. Additional immunohistochemical stainings revealed increased numbers of plasma cells, histiocytes and T lymphocytes. Interestingly, spongiosis was largely absent in all biopsies. We report on patients with AD treated with dupilumab developing a paradoxical erythema in a head and neck distribution. Both clinically and histopathologically we found a heterogeneous response, which was most suggestive of a drug-induced skin reaction.
Subject(s)
Dermatitis, Atopic , Eczema , Antibodies, Monoclonal, Humanized , Dermatitis, Atopic/drug therapy , Double-Blind Method , Erythema/chemically induced , Humans , Treatment OutcomeABSTRACT
Fasciola jacksoni is a significant contributor to the health and mortality of Asian elephants, particularly those in Sri Lanka. Despite the impact of fascioliasis on elephant populations, it is a neglected veterinary disease with limited taxonomic understanding. Molecular characterization and phylogenetic analysis of F. jacksoni were carried out to evaluate its suggested basal position in the Fasciolidae. Adult worms were collected during post-mortem of elephants, and eggs were collected from living elephants in National parks across Sri Lanka. Using the mitochondrial genes nicotinamide dehydrogenase subunit 1 (nad1) and cytochrome oxidase subunit 1 (cox1), and a partial 28S ribosomal DNA (28S rDNA), DNA sequences were generated from the F. jacksoni adult and egg material. Maximum likelihood (ML) phylogenetic analyses did not resolve F. jacksoni to be basal to the Fasciolidae. Furthermore, the ML analyses showed that the genus Fasciola was not monophyletic and that F. jacksoni was a sister species to the deer liver fluke Fascioloides magna. A clear framework is required to determine the taxonomic status of F. jacksoni and this current study provides the first detailed application of molecular techniques from multiple hosts across Sri Lanka with the production of reference DNA sequences for this important parasite.
Subject(s)
Elephants/parasitology , Fasciola/classification , Fasciola/genetics , Fascioliasis/veterinary , Phylogeny , Animals , Cluster Analysis , DNA, Helminth/chemistry , DNA, Helminth/genetics , DNA, Mitochondrial/chemistry , DNA, Mitochondrial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Electron Transport Complex IV/genetics , Fasciola/isolation & purification , Fascioliasis/parasitology , NADH Dehydrogenase/genetics , RNA, Ribosomal, 28S/genetics , Sequence Analysis, DNA , Sri LankaABSTRACT
This work investigates the on-chip washing process of microparticles and cells using coflow configuration of viscoelastic fluid and Newtonian fluid in a straight microchannel. By adding a small amount of biocompatible polymers into the particle medium or cell culture medium, the induced viscoelasticity can push particles and cells laterally from their original medium to the coflow Newtonian medium. This behavior can be used for particle or cell washing. First, we demonstrated on-chip particle washing by the size-dependent migration speed using coflow of viscoelastic fluid and Newtonian fluid. The critical particle size for efficient particle washing was determined. Second, we demonstrated continuous on-chip washing of Jurkat cells using coflow of viscoelastic fluid and Newtonian fluid. The lateral migration process of Jurkat cells along the channel length was investigated. In addition, the cell washing quality was verified by hemocytometry and flow cytometry with a recovery rate as high as 92.8%. Scanning spectrophotometric measurements of the media from the two inlets and the two outlets demonstrated that diffusion of the coflow was negligible, indicating efficient cell washing from culture medium to phosphate-buffered saline medium. This technique may be a safer, simpler, cheaper, and more efficient alternative to the tedious conventional centrifugation methods and may open up a wide range of biomedical applications.
ABSTRACT
This study aimed to test Raman (400-1800cm-1) and Infra-red (1900-500cm-1) spectroscopies followed by statistical analysis (principal component analysis) to detect molecular changes induced by antibiotics (ampicillin, cefotaxime - cell wall synthesis inhibitors, tetracycline - protein synthesis inhibitor, ciprofloxacin - DNA synthesis inhibitor) against Escherichia coli TOP10. In case of ampicillin and cefotaxime, a decrease in protein bands in both Raman (1240, 1660cm-1), and IR spectra (1230, 1530, 1630cm-1), and an increase in carbohydrate bands (1150, 1020cm-1) in IR spectra were observed. Tetracycline addition caused an increase in nucleic acid bands (775, 1478, 1578cm-1), a sharp decrease in phenylalanine (995cm-1) in Raman spectra and the amide I and amide II bands (1630, 1530cm-1) in IR spectra, an increase in DNA in both Raman (1083cm-1) and IR spectra (1080cm-1). Regarding ciprofloxacin, an increase in nucleic acids (775, 1478, 1578cm-1) in Raman spectra and in protein bands (1230, 1520, 1630cm-1), in DNA (1080cm-1) in IR spectra were detected. Clear discrimination of antibiotic-treated samples compared to the control was recorded, showing that Raman and IR spectroscopies, coupled to principal component analysis for data, could be used to detect molecular modifications in bacteria exposed to different classes of antibiotics. These findings contribute to the understanding of the mechanisms of action of antibiotics in bacteria.
Subject(s)
Anti-Bacterial Agents/pharmacology , Escherichia coli/drug effects , Escherichia coli/ultrastructure , Spectrophotometry, Infrared/methods , Spectrum Analysis, Raman/methods , Ampicillin/pharmacology , Cefotaxime/pharmacology , Ciprofloxacin/pharmacology , VibrationABSTRACT
BACKGROUND AND PURPOSE: Converging evidence suggests that migraine has, in part, a vascular basis. In turn, vascular pathology is a strong risk factor for cognitive decline. In this population-based study, we studied cognition amongst individuals with and without migraine. METHODS: In 6708 participants of the Rotterdam Study, migraine was assessed using a validated questionnaire. Cognition was assessed by the Mini Mental State Examination (MMSE) and a dedicated cognitive test battery. Participants were classified as non-migraineurs (n = 5399), migraineurs (n = 1021) or probable migraineurs (n = 288). Multivariable linear regression was used to cross-sectionally evaluate the association between migraine and cognition, adjusting for age, sex and cardiovascular risk factors. Additionally, we stratified the analysis by sex and by migraine subtype. RESULTS: Migraineurs had higher mean MMSE scores [unstandardized regression coefficient 0.21, (95% confidence interval, 0.08; 0.34)] and global cognition [0.10 (0.04; 0.15)] than non-migraineurs. This difference was particularly marked for migraineurs with aura [MMSE: 0.39 (0.13; 0.66); global cognition: 0.13 (0.01; 0.24)]. Migraineurs performed better on tests of executive function and fine motor skills amongst specific cognitive domains. The difference in MMSE between migraineurs and non-migraineurs was greater in women [0.25 (0.10; 0.40)] than in men [0.13 (-0.15; 0.40)], whereas the difference in global cognition was similar in men and women [0.15 (0.04; 0.27) and 0.09 (0.02; 0.15), respectively]. CONCLUSIONS: Migraineurs, particularly migraineurs with aura, tend to score higher in cognition tests than non-migraineurs. More studies are needed to corroborate these findings.
Subject(s)
Cognition/physiology , Executive Function/physiology , Migraine Disorders/physiopathology , Motor Skills/physiology , Aged , Female , Humans , Male , Middle Aged , Migraine Disorders/epidemiology , Netherlands/epidemiologyABSTRACT
The facultative aerobic bacteria isolated from the mucosa of rectum in patients with colorectal cancer in the zone of malignant tumor and neighboring normal mucosa was studied using molecular-genetic methods. The species attribution of bacteria was implemented using the cultural-morphological analysis and sequencing of the 16S rRNA locus. The microorganisms with the intraepithelial invasion to rectal mucosa isolated were identified as representatives of the adherent-invasive (AIEC) subgroup of Escherichia coli and species Klebsiella pneumonia. The molecular analysis by genetic determinants controlling adhesive, hemolytic, and toxigenic activity revealed that some bacterial isolates were able to produce toxins with potential cancerogenic activity (e.g., colibactin and cytotoxic necrotic factor I). Certain bacterial species isolated from malignant and normal rectum epithelium of the same patient demonstrated no difference between analyzed factors of toxigenicity.
Subject(s)
Colorectal Neoplasms/microbiology , Escherichia coli , Intestinal Mucosa/microbiology , Klebsiella pneumoniae , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Colorectal Neoplasms/pathology , Escherichia coli/genetics , Escherichia coli/isolation & purification , Escherichia coli/pathogenicity , Female , Humans , Intestinal Mucosa/pathology , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/pathogenicity , MaleABSTRACT
AIMS: The aims of this study were to characterize the antibacterial activity and the chemotype of Litsea cubeba leaf essential oil (EO) harvested in North Vietnam and to investigate the biological effects induced by the leaf powder on growth, nonspecific immunity and survival of common carp (Cyprinus carpio) challenged with Aeromonas hydrophila. METHODS AND RESULTS: The EO showed the prevalence of linalool (95%, n = 5). It was bactericidal against the majority of tested strains, with minimum inhibitory concentrations ranging from 0·72 to 2·89 mg ml(-1) (Aer. hydrophila, Edwarsiella tarda, Vibrio furnissii, Vibrio parahaemolyticus, Streptococcus garvieae, Escherichia coli, Salmonella Typhimurium). The fish was fed with 0 (control), 2, 4 and 8% leaf powder supplementation diets for 21 days. Nonspecific immunity parameters (lysozyme, haemolytic and bactericidal activities of plasma) were assessed 21 days after feeding period and before the experimental infection. Weight gain, specific growth rate and feed conversion ratio were improved by supplementation of L. cubeba in a dose-related manner, and a significant difference appeared at the highest dose (8%) when compared to the control. The increase in plasma lysozyme was significant for all the treated groups. Haemolysis activity was higher for the groups fed with 4 and 8% plant powder. Antibacterial activity increased significantly for the 8% dose only. CONCLUSIONS: Litsea cubeba leaf powder increased nonspecific immunity of carps in dose-related manner. After infection with Aer. hydrophila, survivals of fish fed with 4 and 8% L. cubeba doses were significantly higher than those fed with 2% dose and the control. SIGNIFICANCE AND IMPACT OF THE STUDY: A range of 4-8% L. cubeba leaf powder supplementation diet (from specific linalool-rich chemotype) can be used in aquaculture to reduce antibiotic burden and impacts of diseases caused by Aer. hydrophila.
Subject(s)
Aeromonas hydrophila/physiology , Anti-Bacterial Agents/administration & dosage , Carps , Fish Diseases/drug therapy , Gram-Negative Bacterial Infections/veterinary , Litsea/chemistry , Oils, Volatile/administration & dosage , Aeromonas hydrophila/drug effects , Animals , Anti-Bacterial Agents/pharmacology , Aquaculture/methods , Dietary Supplements , Fish Diseases/microbiology , Gram-Negative Bacterial Infections/drug therapy , Gram-Negative Bacterial Infections/microbiology , Immunity, Innate , Microbial Sensitivity Tests , Oils, Volatile/pharmacologyABSTRACT
The Vibrio cholerae O1 (VCO1) El Tor biotype appeared during the seventh cholera pandemic starting in 1961, and new variants of this biotype have been identified since the early 1990s. This pandemic has affected Vietnam, and a large outbreak was reported in southern Vietnam in 2010. Pulsed-field gel electrophoresis (PFGE) and multilocus variable-number tandem-repeat analyses (MLVA) were used to screen 34 VCO1 isolates from the southern Vietnam 2010 outbreak (23 patients, five contact persons, and six environmental isolates) to determine if it was genetically distinct from 18 isolates from outbreaks in southern Vietnam from 1999 to 2004, and two isolates from northern Vietnam (2008). Twenty-seven MLVA types and seven PFGE patterns were identified. Both analyses showed that the 2008 and 2010 isolates were distinctly clustered and separated from the 1999-2004 isolates.
Subject(s)
Cholera/microbiology , Disease Outbreaks , Genetic Variation , Vibrio cholerae O1/genetics , Cholera/epidemiology , Electrophoresis, Gel, Pulsed-Field , Humans , Minisatellite Repeats , Multilocus Sequence Typing , Vietnam/epidemiologyABSTRACT
In this paper, 3D particle focusing in a straight channel with asymmetrical expansion-contraction cavity arrays (ECCA channel) is achieved by exploiting the dean-flow-coupled elasto-inertial effects. First, the mechanism of particle focusing in both Newtonian and non-Newtonian fluids was introduced. Then particle focusing was demonstrated experimentally in this channel with Newtonian and non-Newtonian fluids using three different sized particles (3.2 µm, 4.8 µm, and 13 µm), respectively. Also, the effects of dean flow (or secondary flow) induced by expansion-contraction cavity arrays were highlighted by comparing the particle distributions in a single straight rectangular channel with that in the ECCA channel. Finally, the influences of flow rates and distances from the inlet on focusing performance in the ECCA channel were studied. The results show that in the ECCA channel particles are focused on the cavity side in Newtonian fluid due to the synthesis effects of inertial and dean-drag force, whereas the particles are focused on the opposite cavity side in non-Newtonian fluid due to the addition of viscoelastic force. Compared with the focusing performance in Newtonian fluid, the particles are more easily and better focused in non-Newtonian fluid. Besides, the Dean flow in visco-elastic fluid in the ECCA channel improves the particle focusing performance compared with that in a straight channel. A further advantage is three-dimensional (3D) particle focusing that in non-Newtonian fluid is realized according to the lateral side view of the channel while only two-dimensional (2D) particle focusing can be achieved in Newtonian fluid. Conclusively, this novel Dean-flow-coupled elasto-inertial microfluidic device could offer a continuous, sheathless, and high throughput (>10 000 s(-1)) 3D focusing performance, which may be valuable in various applications from high speed flow cytometry to cell counting, sorting, and analysis.