Transstadial transmission of tick-borne rickettsiae has been well documented. Few studies, however, have evaluated the role of transovarial transmission of tick-borne rickettsiae, particularly in ...nature within the host-vector ecosystem. This cross-sectional study aimed to understand the role of transovarial transmission of tick-borne rickettsiae among feeding ticks at different life stages. Tick eggs laid by engorged wild-caught adult female ticks were pooled and tested for Rickettsia spp. and Anaplasma/Ehrlichia spp. using molecular techniques, while adult fed ticks were tested individually. Additionally, larval and nymphal ticks were collected in the wild from small mammals, pooled and tested for Rickettsia spp. and Anaplasma/Ehrlichia spp. There were 38 fed adult and 618 larvae/nymphs (60 pools total) Dermacentor spp. ticks collected from livestock and rodents. All individual adult ticks and tick pools were positive for Rickettsia spp. While none of the larvae/nymphs were positive for Anaplasma/Ehrlichia spp., two adult fed ticks were positive. Rickettsia spp. DNA was detected in 91% (30/33) of the pooled eggs tested, and one pool of eggs tested positive for Anaplasma/Ehrlichia spp. Sequencing data revealed Rickettsia spp. shared ≥99% identity with R. raoultii ompA. Anaplasma/Ehrlichia spp. shared ≥89% identity with A. ovis 16S ribosomal RNA. This study identified potential transovarial transmission of Rickettsia spp. and Anaplasma spp. among D. nuttalli ticks. Additional studies are needed to further assess the proportion of transovarial transmission occurring in nature to better understand the burden and disease ecology of tick-borne rickettsiae in Mongolia.
Precision medicine, taking account of human individuality in genes, environment, and lifestyle for early disease diagnosis and individualized therapy, has shown great promise to transform medical ...care. Nontargeted metabolomics, with the ability to detect broad classes of biochemicals, can provide a comprehensive functional phenotype integrating clinical phenotypes with genetic and nongenetic factors. To test the application of metabolomics in individual diagnosis, we conducted a metabolomics analysis on plasma samples collected from 80 volunteers of normal health with complete medical records and three-generation pedigrees. Using a broad-spectrum metabolomics platform consisting of liquid chromatography and GC coupled with MS, we profiled nearly 600 metabolites covering 72 biochemical pathways in all major branches of biosynthesis, catabolism, gut microbiome activities, and xenobiotics. Statistical analysis revealed a considerable range of variation and potential metabolic abnormalities across the individuals in this cohort. Examination of the convergence of metabolomics profiles with whole-exon sequences (WESs) provided an effective approach to assess and interpret clinical significance of genetic mutations, as shown in a number of cases, including fructose intolerance, xanthinuria, and carnitine deficiency. Metabolic abnormalities consistent with early indications of diabetes, liver dysfunction, and disruption of gut microbiome homeostasis were identified in several volunteers. Additionally, diverse metabolic responses to medications among the volunteers may assist to identify therapeutic effects and sensitivity to toxicity. The results of this study demonstrate that metabolomics could be an effective approach to complement next generation sequencing (NGS) for disease risk analysis, disease monitoring, and drug management in our goal toward precision care.
Quorum sensing (QS) is a cell—cell communication system that controls gene expression in many bacterial species, mediated by diffusible signal molecules. Although the intracellular regulatory ...mechanisms of QS are often well-understood, the functional roles of QS remain controversial. In particular, the use of multiple signals by many bacterial species poses a serious challenge to current functional theories. Here, we address this challenge by showing that bacteria can use multiple QS signals to infer both their social (density) and physical (mass-transfer) environment. Analytical and evolutionary simulation models show that the detection of, and response to, complex social/physical contrasts requires multiple signals with distinct half-lives and combinatorial (nonadditive) responses to signal concentrations. We test these predictions using the opportunistic pathogen Pseudomonas aeruginosa and demonstrate significant differences in signal decay between its two primary signal molecules, as well as diverse combinatorial responses to dual-signal inputs. QS is associated with the control of secreted factors, and we show that secretome genes are preferentially controlled by synergistic "AND-gate" responses to multiple signal inputs, ensuring the effective expression of secreted factors in high-density and low mass-transfer environments. Our results support a new functional hypothesis for the use of multiple signals and, more generally, show that bacteria are capable of combinatorial communication.
•New method for the analysis of exhaled breath VOCs by TD-GC × GC-FID/qMS.•Optimisation of flow modulation and dual detection alongside clinical requirements.•Addresses key challenges of using GC × ...GC for large-scale breath metabolomics.
Precision medicine has spurred new innovations in molecular pathology leading to recent advances in the analysis of exhaled breath as a non-invasive diagnostic tool. Volatile organic compounds (VOCs) detected in exhaled breath have the potential to reveal a wealth of chemical and metabolomic information. This study describes the development of a method for the analysis of breath, based on automated thermal desorption (TD) combined with flow modulated comprehensive two-dimensional gas chromatography (GC×GC) with dual flame ionisation and quadrupole mass spectrometric detection (FID and qMS). The constrained optimisation and analytical protocol was designed to meet the practical demands of a large-scale multi-site clinical study, while maintaining analytical rigour to produce high fidelity data. The results demonstrate a comprehensive method optimisation for the collection and analysis of breath VOCs by GC×GC, integral to the standardisation and integration of breath analysis within large clinical studies.
Objective To compare outcomes of mesenteric angioplasty and stenting using iCAST covered stents (CS; Atrium, Hudson, NH) or bare metal stents (BMS) in patients with chronic mesenteric ischemia (CMI). ...Methods We reviewed the clinical data of 225 patients (65 male and 160 female; mean age, 72 ± 12 years) treated for CMI at two academic centers (2000-2010). Outcomes were analyzed in patients who had primary intervention or reintervention using BMS (n = 164 patients/197 vessels) or CS (n = 61 patients/67 vessels). End points were freedom from restenosis, symptom recurrence, reinterventions, and patency rates. Results Patients in both groups had similar demographics, cardiovascular risk factors, and extent of disease. In the primary intervention group (mean follow-up, 29 ± 12 months), patients treated by CS had higher freedom from restenosis (92% ± 6% vs 53% ± 4%; P = .003), symptom recurrence (92 ± 4% vs 50 ± 5%; P = .003), reintervention (91% ± 6% vs 56% ± 5%; P = .005), and better primary patency at 3 years (92% ± 6% vs 52% ± 5%; P < .003) than for BMS. In the reintervention group (mean follow-up, 24 ± 9 months), patients treated by CS had higher freedom from restenosis (89% ± 10% vs 49% ± 14%; P < .04), symptom recurrence (100% vs 64%± 9%; P = .001), and reintervention (100% vs 72% ± 9%; P = .03) at 1 year, and a trend toward improved primary patency at 1 year (100% vs 63% ± 9%; P = .054). Secondary patency rates were similar in both groups. Conclusions In this nonrandomized study, CS were associated with less restenosis, recurrences, and reinterventions than BMS in patients undergoing primary interventions or reinterventions for CMI.
We conducted an open label, dose escalation Phase 1 clinical trial of a tetravalent dengue DNA vaccine (TVDV) formulated in Vaxfectin
to assess safety and immunogenicity. A total of 40 dengue- and ...flavivirus-naive volunteers received either low-dose (1 mg) TVDV alone (
= 10, group 1), low-dose TVDV (1 mg) formulated in Vaxfectin (
= 10, group 2), or high-dose TVDV (2 mg, group 3) formulated in Vaxfectin
(
= 20). Subjects were immunized intramuscularly with three doses on a 0-, 30-, 90-day schedule and monitored. Blood samples were obtained after each immunization and various time points thereafter to assess anti-dengue antibody and interferon gamma (IFNγ) T-cell immune responses. The most common adverse events (AEs) across all groups included mild to moderate pain and tenderness at the injection site, which typically resolved within 7 days. Common solicited signs and symptoms included fatigue (42.5%), headache (45%), and myalgias (47.5%). There were no serious AEs related to the vaccine or study procedures. No anti-dengue antibody responses were detected in group 1 subjects who received all three immunizations. There were minimal enzyme-linked immunosorbent assay and neutralizing antibody responses among groups 2 and 3 subjects who completed the immunization schedule. By contrast, IFNγ T-cell responses, regardless of serotype specificity, occurred in 70%, 50%, and 79% of subjects in groups 1, 2, and 3, respectively. The largest IFNγ T-cell responses were among group 3 subjects. We conclude that TVDV was safe and well-tolerated and elicited predominately anti-dengue T-cell IFNγ responses in a dose-related fashion.
ABSTRACT
Introduction
Staphylococcus aureus (SA) is a major human bacterial pathogen increasingly refractory to antibiotics. Given the dearth of novel antibiotics in the developmental pipeline, we ...require concerted efforts at optimizing novel antimicrobial approaches. One promising option is the utilization of bacteriophage (phage) therapy, which has been resurrected as a viable clinical therapeutic. Specifically, an expanded library of phages targeting SA is desired. We surmised that SA-targeting phages would be readily accessible as a major component of the cutaneous microbiome. Specifically, we sought to discern if easily accessible (convenient) and discrete anatomic locations, including the nares, axilla, fingernails, toenails, and web spaces, could provide intact phages via a noninvasive, expedient procedure involving swabbing.
Methods
One hundred subjects participated in systematic skin swab specimen collections. Pooled samples were subject to phage harvesting utilizing the soft agar overlay technique. The approval was secured from the Naval Medical Research Center Institutional Review Board (NMRC 2018.0004 FWA00000152). We utilized the same procedures from known samples containing SA-targeting phages. As another positive control, we employed the same swab and acquired samples from an active wound infection.
Results
As anticipated, there were no adverse events, and the procedure was successfully implemented within the projected 10-minute duration. No phages were identified exploiting this methodology. Positive controls from various environmental samples identified SA-targeting phages as did the wound effluent sample.
Conclusions
Skin swabbing at multiple anatomic sites from 100 adults yielded insufficient biomass for phage recovery. The negative results provide helpful information for future phage isolation attempts. The lessons learned on why this study failed to isolate phages can be easily utilized by others. With a desire to increase our SA-targeting phage library in pursuit of future clinical trials, and acknowledging the paucity of these phages accessible via traditional recovery from environmental sources, we will next acquire large volumes of wound effluent from confirmed infected wounds with SA to optimize the biomass for phage recovery.
Studies from the Spanish influenza era reported that transfusion of influenza-convalescent human blood products reduced mortality in patients with influenza complicated by pneumonia. Treatments for ...H5N1 influenza are unsatisfactory, and convalescent human plasma containing H5N1 antibodies could be an effective therapy during outbreaks and pandemics.
To determine whether transfusion with influenza-convalescent human blood products reduced the risk for death in patients with Spanish influenza pneumonia.
Manual search of English-language journals from 1918 to 1925. Citations from retrieved studies were also searched.
Published English-language studies that had at least 10 patients in the treatment group, used convalescent blood products to treat Spanish influenza pneumonia in a hospital setting, and reported on a control or comparison group.
Two investigators independently extracted data on study characteristics, outcomes, adverse events, and quality.
Eight relevant studies involving 1703 patients were found. Treated patients, who were often selected because of more severe illness, were compared with untreated controls with influenza pneumonia in the same hospital or ward. The overall crude case-fatality rate was 16% (54 of 336) among treated patients and 37% (452 of 1219) among controls. The range of absolute risk differences in mortality between the treatment and control groups was 8% to 26% (pooled risk difference, 21% 95% CI, 15% to 27%). The overall crude case-fatality rate was 19% (28 of 148) among patients who received early treatment (after <4 days of pneumonia complications) and 59% (49 of 83) among patients who received late treatment (after > or =4 days of pneumonia complications). The range of absolute risk differences in mortality between the early treatment group and the late treatment group was 26% to 50% (pooled risk difference, 41% CI, 29% to 54%). Adverse effects included chill reactions and possible exacerbations of symptoms in a few patients.
Studies were few and had many methodologic limitations. No study was a blinded, randomized, or placebo-controlled trial. Some pertinent studies may have been missed.
Patients with Spanish influenza pneumonia who received influenza-convalescent human blood products may have experienced a clinically important reduction in the risk for death. Convalescent human H5N1 plasma could be an effective, timely, and widely available treatment that should be studied in clinical trials.
Rift Valley fever virus (RVFV) is a pathogenic human and livestock RNA virus that poses a significant threat to public health and biosecurity. During RVFV infection, the atypical kinase RIOK3 plays ...important roles in the innate immune response. Although its exact functions in innate immunity are not completely understood, RIOK3 has been shown to be necessary for mounting an antiviral interferon (IFN) response to RVFV in epithelial cells. Furthermore, after immune stimulation, the splicing pattern for RIOK3 mRNA changes markedly, and RIOK3's dominant alternatively spliced isoform, RIOK3 X2, exhibits an opposite effect on the IFN response by dampening it. Here, we further investigate the roles of RIOK3 and its spliced isoform in other innate immune responses to RVFV, namely the NFκB-mediated inflammatory response. We find that while RIOK3 is important for negatively regulating this inflammatory pathway, its alternatively spliced isoform, RIOK3 X2, stimulates it. Overall, these data demonstrate that both RIOK3 and its X2 isoform have unique roles in separate innate immune pathways that respond to RVFV infection.
Since SARS-CoV-2 emerged in late 2019, it spread from China to the rest of the world. An initial concern was the potential for vaccine- or antibody-dependent enhancement (ADE) of disease as had been ...reported with other coronaviruses. To evaluate this, we first developed a ferret model by exposing ferrets to SARS-CoV-2 by either mucosal inoculation (intranasal/oral/ocular) or inhalation using a small particle aerosol. Mucosal inoculation caused a mild fever and weight loss that resolved quickly; inoculation via either route resulted in virus shedding detected in the nares, throat, and rectum for 7–10 days post-infection. To evaluate the potential for ADE, we then inoculated groups of ferrets intravenously with 0.1, 0.5, or 1 mg/kg doses of a human polyclonal anti-SARS-CoV-2 IgG from hyper-immunized transchromosomic bovines (SAB-185). Twelve hours later, ferrets were challenged by mucosal inoculation with SARS-CoV-2. We found no significant differences in fever, weight loss, or viral shedding after infection between the three antibody groups or the controls. Signs of pathology in the lungs were noted in infected ferrets but no differences were found between control and antibody groups. The results of this study indicate that healthy, young adult ferrets of both sexes are a suitable model of mild COVID-19 and that low doses of specific IgG in SAB-185 are unlikely to enhance the disease caused by SARS-CoV-2.
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