ABSTRACT
Molecular sequence data have transformed research on cryptogams (e.g., lichens, microalgae, fungi, and symbionts thereof) but methods are still strongly hampered by the small size and intermingled growth of the target organisms, poor cultivability and detrimental effects of their secondary metabolites. Here, we aim to showcase examples on which a modified direct PCR approach for diverse aspects of molecular work on environmental samples concerning biocrusts, biofilms, and cryptogams gives new options for the research community. Unlike traditional approaches, this methodology only requires biomass equivalent to colonies and fragments of 0.2 mm in diameter, which can be picked directly from the environmental sample, and includes a quick DNA lysis followed by a standardized PCR cycle that allows co-cycling of various organisms/target regions in the same run. We demonstrate that this modified method can (i) amplify the most widely used taxonomic gene regions and those used for applied and environmental sciences from single colonies and filaments of free-living cyanobacteria, bryophytes, fungi, and lichens, including their mycobionts, chlorobionts, and cyanobionts from both isolates and in situ material during co-cycling; (ii) act as a tool to confirm that the dominant lichen photobiont was isolated from the original sample; and (iii) optionally remove inhibitory secondary lichen substances. Our results represent examples which highlight the method's potential for future applications covering mycology, phycology, biocrusts, and lichenology, in particular.IMPORTANCECyanobacteria, green algae, lichens, and other cryptogams play crucial roles in complex microbial systems such as biological soil crusts of arid biomes or biofilms in caves. Molecular investigations on environmental samples or isolates of these microorganisms are often hampered by their dense aggregation, small size, or metabolism products which complicate DNA extraction and subsequent PCRs. Our work presents various examples of how a direct DNA extraction and PCR method relying on low biomass inserts can overcome these common problems and discusses additional applications of the workflow including adaptations.
Subject(s)
Ecosystem , Lichens , Biomass , Fungi/genetics , Lichens/genetics , Polymerase Chain Reaction , DNAABSTRACT
Decades of studies have demonstrated links between biodiversity and ecosystem functioning, yet the generality of the relationships and the underlying mechanisms remain unclear, especially for forest ecosystems. Using 11 tree-diversity experiments, we tested tree species richness-community productivity relationships and the role of arbuscular (AM) or ectomycorrhizal (ECM) fungal-associated tree species in these relationships. Tree species richness had a positive effect on community productivity across experiments, modified by the diversity of tree mycorrhizal associations. In communities with both AM and ECM trees, species richness showed positive effects on community productivity, which could have resulted from complementarity between AM and ECM trees. Moreover, both AM and ECM trees were more productive in mixed communities with both AM and ECM trees than in communities assembled by their own mycorrhizal type of trees. In communities containing only ECM trees, species richness had a significant positive effect on productivity, whereas species richness did not show any significant effects on productivity in communities containing only AM trees. Our study provides novel explanations for variations in diversity-productivity relationships by suggesting that tree-mycorrhiza interactions can shape productivity in mixed-species forest ecosystems.
Subject(s)
Biodiversity , Mycorrhizae , Trees , Mycorrhizae/physiology , Trees/microbiology , Species SpecificityABSTRACT
INTRODUCTION: Previously published data are conflicting regarding the ability of tenecteplase versus alteplase to produce early recanalization of an intracranial large vessel occlusion. We compared the performance of each thrombolytic in a stroke network. METHODS: We queried our prospectively collected code stroke registry for basilar, internal carotid, or proximal middle cerebral artery occlusion patients treated with intravenous thrombolysis from 11/17/2021-9/16/2023. The primary outcome was early recanalization, defined using angiographic or clinical criteria. Secondary and safety outcomes included 90-day functional independence and symptomatic intracranial hemorrhage. A multivariable regression analysis was performed to determine independent associations with the primary outcome. RESULTS: 233 patients, with mean age 66.9 (16.6) years and median National Institutes of Health Stroke Scale score 15 (10-21), were included. One-hundred twenty-four of 233 (53.2%) patients were treated with alteplase while 109/233 (46.8%) were treated with tenecteplase. Endovascular thrombectomy was performed in 82% of subjects. Early recanalization rates were similar between the groups (alteplase 22.6%, tenecteplase 14.7%; p=0.14), as were rates of 90-day independent neurological function, symptomatic intracranial hemorrhage, and mortality. Patients with an internal carotid artery occlusion or with higher presenting stroke severity were less likely to achieve early recanalization. CONCLUSIONS: Tenecteplase and alteplase have similar rates of early recanalization, 90-day functional independence, and safety outcomes in large vessel occlusion patients. Occlusion site and stroke severity predict response to thrombolysis. Future studies may investigate other factors associated with a positive response to thrombolytics as expanded treatment indications are explored.
ABSTRACT
Experimental evolution provides a powerful tool for examining how Bdellovibrio evolves in response to unique selective pressures associated with its predatory lifestyle. We tested how Bdellovibrio sp. NC01 adapts to long-term coculture with Pseudomonas sp. NC02, which is less susceptible to predation compared to other Gram-negative bacteria. Analyzing six replicate Bdellovibrio populations across six time points spanning 40 passages and 2,880 h of coculture, we detected 30 to 40 new mutations in each population that exceeded a frequency of 5%. Nonsynonymous substitutions were the most abundant type of new mutation, followed by small indels and synonymous substitutions. After completing the final passage, we detected 20 high-frequency (>75%) mutations across all six evolved Bdellovibrio populations. Eighteen of these alter protein sequences, and most increased in frequency rapidly. Four genes acquired a high-frequency mutation in two or more evolved Bdellovibrio populations, reflecting parallel evolution and positive selection. The genes encode a sodium/phosphate cotransporter family protein (Bd2221), a metallophosphoesterase (Bd0054), a TonB family protein (Bd0396), and a hypothetical protein (Bd1601). Tested prey range and predation efficiency phenotypes did not differ significantly between evolved Bdellovibrio populations and the ancestor; however, all six evolved Bdellovibrio populations demonstrated enhanced starvation survival compared to the ancestor. These results suggest that, instead of evolving improved killing of Pseudomonas sp. NC02, Bdellovibrio evolved to better withstand nutrient limitation in the presence of this prey strain. The mutations identified here point to genes and functions that may be important for Bdellovibrio adaptation to the different selective pressures of long-term coculture with Pseudomonas. IMPORTANCE Bdellovibrio attack and kill Gram-negative bacteria, including drug-resistant pathogens of animals and plants. This lifestyle is unusual among bacteria, and it imposes unique selective pressures on Bdellovibrio. Determining how Bdellovibrio evolve in response to these pressures is valuable for understanding the mechanisms that govern predation. We applied experimental evolution to test how Bdellovibrio sp. NC01 evolved in response to long-term coculture with a single Pseudomonas strain, which NC01 can kill, but with low efficiency. Our experimental design imposed different selective pressures on the predatory bacteria and tracked the evolutionary trajectories of replicate Bdellovibrio populations. Using genome sequencing, we identified Bdellovibrio genes that acquired high-frequency mutations in two or more populations. Using phenotype assays, we determined that evolved Bdellovibrio populations did not improve their ability to kill Pseudomonas, but rather are better able to survive starvation. Overall, our results point to functions that may be important for Bdellovibrio adaptation.
Subject(s)
Bdellovibrio , Animals , Bdellovibrio/genetics , Coculture Techniques , Predatory Behavior , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Gram-Negative Bacteria/metabolismABSTRACT
An 8-year-old Saanen goat doe was seen for inappetence, tachycardia, and intermittent bluish-grey discoloration of the oral mucous membranes. On physical examination, the goat was mildly tachypneic and tachycardic, with reduced sounds auscultated on the left side of the thorax. Euthanasia was elected. Necropsy revealed an infiltrative, multinodular mass within the left thoracic cavity and innumerable small, tan nodules disseminated across the pleura of the lungs, thoracic walls, and diaphragm. Upon histologic examination, the mass was composed of highly pleomorphic, fusiform to polygonal cells. Neoplastic cells exhibited positive immunoreactivity for both cytokeratin and vimentin, consistent with a diagnosis of biphasic pleural mesothelioma. Key clinical message: Mesothelioma has rarely been described in the goat but should be considered as a differential diagnosis for thoracic masses in small ruminants, along with thymoma; metastatic neoplasia; carcinomatosis; and granulomatous lesions caused by parasites, bacteria, and fungi.
Mésothéliome pleural biphasique chez une chèvre. Une chèvre Saanen âgée de 8 ans a été vue pour de l'inappétence, une tachycardie et une décoloration gris bleuâtre intermittente des muqueuses buccales. À l'examen physique, la chèvre était légèrement tachypnéique et tachycardique, avec des sons réduits auscultés du côté gauche du thorax. Il a été décidé d'euthanasier l'animal. L'autopsie a révélé une masse multinodulaire infiltrante dans la cavité thoracique gauche et d'innombrables petits nodules brun clair disséminés à travers la plèvre pulmonaire, les parois thoraciques et le diaphragme. À l'examen histologique, la masse était composée de cellules hautement pléomorphes, fusiformes à polygonales. Les cellules néoplasiques ont présenté une immunoréactivité positive pour la cytokératine et la vimentine, compatible avec un diagnostic de mésothéliome pleural biphasique.Message clinique clé:Le mésothéliome a rarement été décrit chez la chèvre mais doit être considéré comme un diagnostic différentiel des masses thoraciques chez les petits ruminants, avec le thymome, la néoplasie métastatique, la carcinomatose et les lésions granulomateuses causées par des parasites, des bactéries et des champignons.(Traduit par Dr Serge Messier).
Subject(s)
Carcinoma , Goat Diseases , Mesothelioma , Animals , Goats , Euthanasia, Animal , Mesothelioma/diagnosis , Mesothelioma/veterinary , Autopsy/veterinary , Carcinoma/veterinary , Goat Diseases/diagnosisABSTRACT
Perturbation-induced reach-to-grasp reactions are dependent on vision to capture environmental features of potential support surfaces. Previous research proposed the use of an intrinsic visuospatial map of the environment to reduce delays in motor responses (e.g., stepping, grasping a handrail). Forming such a map from foveal vision would be challenging during movement as it would require constant foveal scanning. The objective of this study was to determine if compensatory reach-to-grasp reactions could be successfully executed while relying on a visuospatial map acquired using peripheral vision. Subjects were instructed to respond to a perturbation by grasping a handle randomly located at 0°, 20° or 40° in their field of view under three visual conditions: full vision throughout the entire trial (FV), vision available prior to perturbation only (MAP), and vision available post-perturbation only (ONLINE). Electromyography was used to determine reaction time and kinematic data were collected to determine initial reach angle. Overall, participants were successful in arresting whole-body motion across all visual conditions and handle locations. Initial reach angles were target specific when vision was available prior to perturbation onset (FV and MAP). However, the 40° handle location produced a greater initial reach angle in MAP, suggesting some limitations for mapping in the further visual periphery. These findings suggest that peripheral vision contributes to the ability to spatially locate targets by building an a priori visuospatial map, which benefits the control of rapid compensatory reach-to-grasp reactions evoked in the response to unpredictable events of instability.
Subject(s)
Hand Strength , Psychomotor Performance , Hand Strength/physiology , Humans , Movement/physiology , Psychomotor Performance/physiology , Reaction Time/physiology , Visual Perception/physiologyABSTRACT
Previous studies have described the clinical, serological and pathological features of patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and antibodies directed against the paranodal proteins neurofascin-155, contactin-1 (CNTN1), contactin-associated protein-1 (Caspr1), or nodal forms of neurofascin. Such antibodies are useful for diagnosis and potentially treatment selection. However, antibodies targeting Caspr1 only or the Caspr1/CNTN1 complex have been reported in few patients with CIDP. Moreover, it is unclear if these patients belong to the same pathophysiological subgroup. Using cell-based assays in routine clinical testing, we identified sera from patients with CIDP showing strong membrane reactivity when both CNTN1 and Caspr1 were co-transfected (but not when CNTN1 was transfected alone). Fifteen patients (10 male; aged between 40 and 75) with antibodies targeting Caspr1/CNTN1 co-transfected cells were enrolled for characterization. The prevalence of anti-Caspr1/CNTN1 antibodies was 1.9% (1/52) in the Sant Pau CIDP cohort, and 4.3% (1/23) in a German cohort of acute-onset CIDP. All patients fulfilled European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) definite diagnostic criteria for CIDP. Seven (47%) were initially diagnosed with Guillain-Barré syndrome due to an acute-subacute onset. Six (40%) patients had cranial nerve involvement, eight (53%) reported neuropathic pain and 12 (80%) ataxia. Axonal involvement and acute denervation were frequent in electrophysiological studies. Complete response to intravenous immunoglobulin was not observed, while most (90%) responded well to rituximab. Enzyme-linked immunosorbent assay (ELISA) and teased nerve fibre immunohistochemistry confirmed reactivity against the paranodal Caspr1/CNTN1 complex. Weaker reactivity against Caspr1 transfected alone was also detected in 10/15 (67%). Sera from 13 of these patients were available for testing by ELISA. All 13 samples reacted against Caspr1 by ELISA and this reactivity was enhanced when CNTN1 was added to the Caspr1 ELISA. IgG subclasses were also investigated by ELISA. IgG4 was the predominant subclass in 10 patients, while IgG3 was predominant in other three patients. In conclusion, patients with antibodies to the Caspr1/CNTN1 complex display similar serological and clinical features and constitute a single subgroup within the CIDP syndrome. These antibodies likely target Caspr1 primarily and are detected with Caspr1-only ELISA, but reactivity is optimal when CNTN1 is added to Caspr1 in cell-based assays and ELISA.
Subject(s)
Autoantibodies/immunology , Autoantigens/immunology , Cell Adhesion Molecules, Neuronal/immunology , Contactin 1/immunology , Polyradiculoneuropathy, Chronic Inflammatory Demyelinating/immunology , Adult , Aged , Female , Humans , Male , Middle AgedABSTRACT
Screening colonoscopy is recommended for polyp detection and colorectal cancer prevention for those aged 50-75 years. The aim of this study was to determine colon polyp incidence rates detected through screening colonoscopies in the Southeast United States. A retrospective chart review was conducted to determine polyp rates. Charts with a diagnostic code of "screening" colonoscopy were reviewed for age, gender, number of polyps, and type of polyps. The number of charts reviewed was 534, with a total of 239 found to have polyps. Polyp type was defined as hyperplastic and adenomatous, with all adenomatous types grouped together. Descriptive statistics were used for data analysis. The median age of participants was 62 years with 58% being male. The combined rate of colon polyp detection was 44.6%. Seventy percent of the overall sample was found to have at least one polyp. From 16% to 20% of the study population had mixed (adenomatous and hyperplastic) polyps. This study supports the need for continued screening colonoscopies for polyp detection and removal. Education is key and nurses are often the ones who have the greatest educational opportunity. This study indicates the need for further research that may support colorectal cancer screening beginning at an earlier age.
Subject(s)
Adenoma , Colonic Polyps , Colonic Polyps/diagnosis , Colonic Polyps/epidemiology , Colonoscopy , Female , Humans , Male , Mass Screening , Middle Aged , Retrospective StudiesABSTRACT
The healthcare system has undergone a transformational shift toward people-centred care (PCC), and healthcare leaders are accountable for enabling this culture change. This paper describes the University Health Network's journey of using a person-centred approach for cultural transformation, reflecting on (a) the leadership elements required to build and sustain a culture of PCC; (b) the importance of establishing a Patient Declaration of Values, which is a framework for patient care; and (c) how this culture led our approach during the COVID-19 pandemic.
Subject(s)
COVID-19 , Leadership , COVID-19/epidemiology , Humans , Pandemics , Patient-Centered Care , SARS-CoV-2ABSTRACT
Diverse plant communities are often more productive than mono-specific ones. Several possible mechanisms underlie this phenomenon but their relative importance remains unknown. Here we investigated whether light interception alone or in combination with light use efficiency (LUE) of dominant and subordinate species explained greater productivity of mixtures relative to monocultures (i.e. overyielding) in 108 young experimental tree communities. We found mixed-species communities that intercepted more light than their corresponding monocultures had 84% probability of overyielding. Enhanced LUE, which arose via several pathways, also mattered: the probability of overyielding was 71% when, in a mixture, species with higher 'inherent' LUE (i.e. LUE in monoculture) intercepted more light than species with lower LUE; 94% when dominant species increased their LUE in mixture; and 79% when subordinate species increased their LUE. Our results suggest that greater light interception and greater LUE, generated by inter and intraspecific variation, together drive overyielding in mixed-species forests.
Subject(s)
Biodiversity , Forests , Biomass , PlantsABSTRACT
Feedbacks are an essential feature of resilient socio-economic systems, yet the feedbacks between biodiversity, ecosystem services and human wellbeing are not fully accounted for in global policy efforts that consider future scenarios for human activities and their consequences for nature. Failure to integrate feedbacks in our knowledge frameworks exacerbates uncertainty in future projections and potentially prevents us from realizing the full benefits of actions we can take to enhance sustainability. We identify six scientific research challenges that, if addressed, could allow future policy, conservation and monitoring efforts to quantitatively account for ecosystem and societal consequences of biodiversity change. Placing feedbacks prominently in our frameworks would lead to (i) coordinated observation of biodiversity change, ecosystem functions and human actions, (ii) joint experiment and observation programmes, (iii) more effective use of emerging technologies in biodiversity science and policy, and (iv) a more inclusive and integrated global community of biodiversity observers. To meet these challenges, we outline a five-point action plan for collaboration and connection among scientists and policymakers that emphasizes diversity, inclusion and open access. Efforts to protect biodiversity require the best possible scientific understanding of human activities, biodiversity trends, ecosystem functions and-critically-the feedbacks among them.
Subject(s)
Conservation of Natural Resources , Ecosystem , Biodiversity , Feedback , Humans , PolicyABSTRACT
[This corrects the article DOI: 10.2196/23487.].
ABSTRACT
BACKGROUND: Effective help for depression and anxiety reaches a small proportion of people who might benefit from it. The scale of the problem suggests the need for effective, safe web-based public health services delivered directly to the public. One model, the Big White Wall (BWW), offers peer support at low cost. As these interventions are delivered digitally, we tested whether a randomized controlled trial (RCT) intervention could also be fully delivered and evaluated digitally. OBJECTIVE: This study aims to determine the reach, feasibility, acceptability, baseline costs, and outcomes of a public health campaign for an automated RCT of the BWW, providing digital peer support and information, compared with a standard website used by the National Health Service Moodzone (MZ), to people with probable mild-to-moderate depression and anxiety disorder. The primary outcome was the change in self-rated well-being at 6 weeks, measured using the Warwick-Edinburgh Mental Well-Being Scale. METHODS: An 18-month campaign was conducted across Nottinghamshire, the United Kingdom (target population 914,000) to advertise the trial directly to the public through general marketing, web-based and social media sources, health services, other public services, and third-sector groups. The population reach of this campaign was examined by the number of people accessing the study website and self-registering to the study. A pragmatic, parallel-group, single-blind RCT was then conducted using a fully automated trial website in which eligible participants were randomized to receive either 6 months of access to BWW or signposted to MZ. Those eligible for participation were aged >16 years with probable mild-to-moderate depression or anxiety disorders. RESULTS: Of 6483 visitors to the study website, 1510 (23.29%) were eligible. Overall, 790 of 1510 (52.32%) visitors participated. Of 790 visitors, 397 (50.3%) were randomized to BWW and 393 (49.7%) to MZ. Their mean age was 38 (SD 13.8) years, 81.0% (640/790) were female, 93.4% (738/790) were White, and 47.4% (271/572) had no contact with health services in the previous 3 months. We estimated 3-month productivity losses of £1001.01 (95% CI 868.75-1133.27; US $1380.79; 95% CI 1198.35-1563.23) per person for those employed. Only 16.6% (131/790) participants completed the primary outcome assessment. There were no differences in the primary or secondary outcomes between the 2 groups. CONCLUSIONS: Most participants reached and those eligible for this trial of digital interventions were White women not in recent contact with health services and whose productivity losses represent a significant annual societal burden. A fully automated RCT recruiting directly from the public failed to recruit and retain sufficient participants to test the clinical effectiveness of this digital intervention, primarily because it did not personally engage participants and explain how these unfamiliar interventions might benefit them. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN) 12673428; https://www.isrctn.com/ISRCTN12673428. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/resprot.8061.
Subject(s)
Depression , Self-Management , Adult , Anxiety/therapy , Anxiety Disorders/therapy , Depression/therapy , Female , Humans , Internet , United KingdomABSTRACT
Background and Purpose- A distinguishing feature of our Stroke Network is telestroke nurses who remotely facilitate evaluations. To enable expeditious transfer of large vessel occlusion (LVO) acute ischemic stroke patients presenting to nonthrombectomy centers, the telestroke nurses must immediately identify color thresholded computerized tomography perfusion (CTP) patterns consistent with internal carotid artery (ICA), middle cerebral artery (MCA) segment 1(M1), and MCA segment 2 (M2) LVO acute ischemic stroke. Methods- We developed a 6-month series of tutorials and tests for 16 telestroke nurses, focusing on CTP pattern recognition consistent with ICA, M1, or M2 LVO acute ischemic stroke. We simultaneously conducted a prospective cohort study to evaluate the impact of this intervention. Results- Telestroke nurses demonstrated good accuracy in detecting ICA, M1, or M2 LVO during the first 3 months of teaching (83%-94% accurate). This significantly improved during the last 3 months (99%-100%), during which the likelihood of correctly identifying the presence of any one of these LVOs exceeded that of the first 3 months (P<0.001). There was a higher probability of correctly identifying any CTP pattern as consistent with either an ICA, M1, or M2 occlusion versus other types of occlusions or nonocclusions (odds ratio, 5.22 [95% CI, 3.2-8.5]). Over time, confidence for recognizing CTP patterns consistent with an ICA, M1, or M2 LVO did not differ significantly. Conclusions- A series of tutorials and tests significantly increased the likelihood of telestroke nurses correctly identifying CTP patterns consistent with ICA, M1, or M2 LVOs, with the benefit of these tutorials and test reviews peaking and plateauing at 4 months.
Subject(s)
Carotid Artery, Internal/diagnostic imaging , Cerebral Angiography , Education, Nursing, Continuing , Middle Cerebral Artery/diagnostic imaging , Nurses , Stroke/diagnostic imaging , Telemedicine , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective StudiesABSTRACT
BACKGROUND: Abnormal temporal discrimination in cervical dystonia is hypothesized to be attributable to disrupted processing in the superior colliculus. The fast, luminance-based, retinotectal pathway, projects to the superior colliculus; chromatic stimuli responses, by the retino-geniculo-calcarine pathway, are up to 30 ms longer. OBJECTIVES: We sought to interrogate visual processing and reaction times in patients with cervical dystonia compared with healthy controls. We hypothesized that cervical dystonia patients would have impaired reaction times to luminance based stimuli accessing the retino-tectal pathway in comparison to healthy control participants. METHODS: In 20 cervical dystonia and 20 age-matched control participants, we compared reaction times to two flashing visual stimuli: (1) a chromatic annulus and (2) a luminant, noncolored annulus. Participants pressed a joystick control when they perceived the annulus flashing. RESULTS: Reaction times in control participants were 20 ms significantly faster in the luminant condition than the chromatic (P = 0.017). Patients with cervical dystonia had no reaction time advantage in response to the luminant stimulus. CONCLUSION: Cervical dystonia patients (compared to control participants) demonstrated no reduction in their reaction time to luminant stimuli, processed through the retinotectal pathway. This finding is consistent with superior colliculus dysfunction in cervical dystonia. © 2020 International Parkinson and Movement Disorder Society.
Subject(s)
Movement Disorders , Torticollis , Humans , Reaction Time , Superior Colliculi , Visual PerceptionABSTRACT
PURPOSE: This study investigated whether muscle cooling and its associated effects on skeletal muscle oxidative responses, blood gases, and hormonal concentrations influenced energy metabolism during cycling. METHODS: Twelve healthy participants (Males: seven; Females: five) performed two steady-state exercise sessions at 70% of ventilatory threshold on a cycle ergometer. Participants completed one session with pre-exercise leg cooling until muscle temperature (Tm) decreased by 6 °C (LCO), and a separate session without cooling (CON). They exercised until Tm returned to baseline and for an additional 30 min. Cardiovascular, respiratory, metabolic, hemodynamic variables, and skeletal muscle tissue oxidative responses were assessed continuously. Venous blood samples were collected to assess blood gases, and hormones. RESULTS: Heart rate, stroke volume, and cardiac output all increased across time but were not different between conditions. VÌO2 was greater in LCO when muscle temperature was restored until the end of exercise (p < 0.05). Cycling in the LCO condition induced lower oxygen availability, tissue oxygenation, blood pH, sO2%, and pO2 (p < 0.05). Insulin concentrations were also higher in LCO vs. CON (p < 0.05). Importantly, stoichiometric equations from respiratory gases indicated no differences in fat and CHO oxidation between conditions. CONCLUSION: The present study demonstrated that despite muscle cooling and the associated oxidative and biochemical changes, energy metabolism remained unaltered during cycling. Whether lower local and systemic oxygen availability is counteracted via a cold-induced activation of lipid metabolism pathways needs to be further investigated.
Subject(s)
Energy Metabolism , Exercise , Hypothermia, Induced , Muscle, Skeletal/metabolism , Oxygen Consumption , Adult , Body Temperature , Carbon Dioxide/blood , Female , Heart Rate , Hormones/blood , Humans , Lipid Metabolism , Male , Muscle, Skeletal/physiology , Oxygen/bloodABSTRACT
BACKGROUND: Women with a history of spontaneous preterm birth (SPTB) are at a significantly increased risk for recurrent preterm birth (PTB). To date, only one large U.S. clinical trial comparing 17-OHPC (17-α-hydroxyprogesterone caproate or "17P") to placebo has been published, and this trial was stopped early due to a large treatment benefit. OBJECTIVE: This study aimed to assess whether 17-OHPC decreases recurrent PTB and neonatal morbidity in women with a prior SPTB in a singleton gestation. STUDY DESIGN: This was a double-blind, placebo-controlled international trial involving women with a previous singleton SPTB (clinicaltrials.gov: NCT01004029). Women were enrolled at 93 clinical centers (41 in the United States and 52 outside the United States) between 160/7 to 206/7 weeks in a 2:1 ratio, to receive either weekly intramuscular (IM) injections of 250 mg of 17-OHPC or an inert oil placebo; treatment was continued until delivery or 36 weeks. Co-primary outcomes were PTB < 35 weeks and a neonatal morbidity composite index. The composite included any of the following: neonatal death, grade 3 or 4 intraventricular hemorrhage, respiratory distress syndrome, bronchopulmonary dysplasia, necrotizing enterocolitis, or proven sepsis. A planned sample size of 1,707 patients was estimated to provide 98% power to detect a 30% reduction in PTB < 35 weeks (30% to 21%) and 90% power to detect a 35% reduction in neonatal composite index (17%-11%) using a two-sided type-I error of 5%. Finally, this sample size would also provide 82.8% power to rule out a doubling in the risk of fetal/early infant death assuming a 4% fetal/early infant death rate. Analysis was performed according to the intention-to-treat principle. RESULTS: Baseline characteristics between the 1,130 women who received 17-OHPC and 578 women who received placebo were similar. Overall, 87% of enrolled women were Caucasian, 12% had >1 prior SPTB, 7% smoked cigarettes, and 89% were married/lived with partner. Prior to receiving study drug, 73% women had a transvaginal cervical length measurement performed and <2% had cervical shortening <25 mm. There were no significant differences in the frequency of PTB < 35 weeks (17-OHPC 11.0% vs. placebo 11.5%; relative risk = 0.95 [95% confidence interval (CI): 0.71-1.26]) or neonatal morbidity index (17-OHPC 5.6% vs. placebo 5.0%; relative risk = 1.12 [95% CI: 0.68-1.61]). There were also no differences in frequency of fetal/early infant death (17-OHPC 1.7% vs. placebo 1.9%; relative risk = 0.87 [95% CI: 0.4-1.81]. Maternal outcomes were also similar. In the subgroup of women enrolled in the United States (n = 391; 23% of all patients), although the rate of PTB < 35 weeks was higher than the overall study population, there were no statistically significant differences between groups (15.6% vs. 17.6%; relative risk = 0.88 [95% CI: 0.55, 1.40]. CONCLUSION: In this study population, 17-OHPC did not decrease recurrent PTB and was not associated with increased fetal/early infant death.
Subject(s)
17 alpha-Hydroxyprogesterone Caproate/therapeutic use , Infant, Newborn, Diseases/prevention & control , Pregnancy Outcome , Premature Birth/prevention & control , Progestins/therapeutic use , 17 alpha-Hydroxyprogesterone Caproate/adverse effects , Double-Blind Method , Female , Gestational Age , Humans , Infant, Newborn , Infant, Newborn, Diseases/epidemiology , Injections, Intramuscular , Perinatal Death , Pregnancy , Pregnancy Complications/epidemiology , Progestins/adverse effects , Secondary Prevention , Treatment FailureABSTRACT
The host's intestinal microbiota contributes to endocrine and metabolic responses, but a dysbiosis in this environment can lead to obesity and insulin resistance. Recent work has demonstrated a role for microbial metabolites in the regulation of gut hormones, including the metabolic hormone, glucagon-like peptide-1 (GLP-1). Muramyl dipeptide (MDP) is a bacterial cell wall component which has been shown to improve insulin sensitivity and glucose tolerance in diet-induced obese mice by acting through the nucleotide oligomerization domain 2 (NOD2) receptor. The purpose of this study was to understand the effects of MDP on GLP-1 secretion and glucose regulation. We hypothesized that MDP enhances glucose tolerance by inducing intestinal GLP-1 secretion through NOD2 activation. First, we observed a significant increase in GLP-1 secretion when murine and human L-cells were treated with a fatty acid MDP derivative (L18-MDP). Importantly, we demonstrated the expression of the NOD2 receptor in mouse intestine and in L-cells. In mice, two intraperitoneal injections of MDP (5 mg/kg body weight) caused a significant increase in fasting total GLP-1 in chow-fed mice, however this did not lead to an improvement in oral glucose tolerance. When mice were exposed to a high-fat diet, they eventually lost this MDP-induced GLP-1 release. Finally, we demonstrated in L-cells that hyperglycemic conditions reduce the mRNA expression of NOD2 and GLP-1. Together these findings suggest MDP may play a role in enhancing GLP-1 during normal glycemic conditions but loses its ability to do so in hyperglycemia.
Subject(s)
Acetylmuramyl-Alanyl-Isoglutamine/pharmacology , Glucagon-Like Peptide 1/metabolism , Hyperglycemia/metabolism , Obesity/metabolism , Animals , Dietary Fats/adverse effects , Dietary Fats/pharmacology , Female , Humans , Hyperglycemia/chemically induced , Hyperglycemia/pathology , Male , Mice , Nod2 Signaling Adaptor Protein/metabolism , Obesity/chemically induced , Obesity/pathologyABSTRACT
We present a 32-year old woman with a 9-year history of upper facial swelling. A workup by the ophthalmology department led to the diagnosis of Melkersson-Rosenthal syndrome. Re-evaluation in our dermatology clinic confirmed a diagnosis of Morbihan disease. Herein, we review case reports and case series of upper facial swelling in the dermatologic and ophthalmologic literature. Although the two entities share histopathological changes, they tend to have different clinical presentations. Melkersson-Rosenthal syndrome appears to be more likely diagnosed in the ophthalmologic literature when the clinical presentation and histopathology may be more consistent with Morbihan disease. In a patient with upper facial swelling, an absence of orolabial swelling, and lack of facial neuropathy, we argue for a diagnosis of Morbihan disease over Melkersson-Rosenthal syndrome, especially if the patient has a history of rosacea.
Subject(s)
Edema/diagnosis , Melkersson-Rosenthal Syndrome/diagnosis , Adult , Diagnosis, Differential , Edema/pathology , Erythema/diagnosis , Female , Humans , Rosacea/complications , Rosacea/diagnosis , Skin/pathologyABSTRACT
Defining phenotypic and associated genotypic variation among Bdellovibrio may further our understanding of how this genus attacks and kills different Gram-negative bacteria. We isolated Bdellovibrio sp. NC01 from soil. Analysis of 16S rRNA gene sequences and average amino acid identity showed that NC01 belongs to a different species than the type species bacteriovorus. By clustering amino acid sequences from completely sequenced Bdellovibrio and comparing the resulting orthologue groups to a previously published analysis, we defined a 'core genome' of 778 protein-coding genes and identified four protein-coding genes that appeared to be missing only in NC01. To determine how horizontal gene transfer (HGT) may have impacted NC01 genome evolution, we performed genome-wide comparisons of Bdellovibrio nucleotide sequences, which indicated that eight NC01 genomic regions were likely acquired by HGT. To investigate how genome variation may impact predation, we compared protein-coding gene content between NC01 and the B. bacteriovorus type strain HD100, focusing on genes implicated as important in successful killing of prey. Of these, NC01 is missing ten genes that may play roles in lytic activity during predation. Compared to HD100, NC01 kills fewer tested prey strains and kills Escherichia coli ML35 less efficiently. NC01 causes a smaller log reduction in ML35, after which the prey population recovers and the NC01 population decreases. In addition, NC01 forms turbid plaques on lawns of E. coli ML35, in contrast to clear plaques formed by HD100. Linking phenotypic variation in interactions between Bdellovibrio and Gram-negative bacteria with underlying Bdellovibrio genome variation is valuable for understanding the ecological significance of predatory bacteria and evaluating their effectiveness in clinical applications.