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The distribution of genetic diversity in invasive plant populations can have important management implications. Alligatorweed [Alternanthera philoxeroides (Mart.) Griseb.] was introduced into the United States around 1900 and has since spread throughout much of the southern United States and California. A successful biological control program was initiated in the late 1960s that reduced A. philoxeroides in the southern United States, although control has varied geographically. The degree to which variation among genotypes may be responsible for variation in control efficacy has not been well studied due to a lack of genetic data. We sampled 373 plants from 90 sites across the United States and genotyped all samples at three chloroplast regions to help inform future management efforts. Consistent with clonal spread, there was high differentiation between sites, yet we found six haplotypes and high haplotype diversity (mean h = 0.48) across states, suggesting this plant has been introduced multiple times. Two of the haplotypes correspond to previously described biotypes that differ in their susceptibility to herbicides and herbivory. The geographic distribution of the three common haplotypes varied by latitude and longitude, while the other haplotypes were widespread or localized to one or a few sites. All the haplotypes we screened are hexaploid (6n = 102), which may enhance biological control. Future studies can use these genetic data to determine whether genotypes differ in their invasiveness or respond differently to control measures. Some states, for instance, have mainly a single haplotype that may respond more uniformly to a single control strategy, whereas other states may require a variety of control strategies. These data will also provide the basis for identifying the source regions in South America, which may lead to the discovery of new biological control agents more closely matched to particular genotypes.
Dietary protein is a pre-requisite for the maintenance of skeletal muscle mass; stimulating increases in muscle protein synthesis (MPS), via essential amino acids (EAA), and attenuating muscle protein breakdown, via insulin. Muscles are receptive to the anabolic effects of dietary protein, and in particular the EAA leucine, for only a short period (i.e. about 2–3 h) in the rested state. Thereafter, MPS exhibits tachyphylaxis despite continued EAA availability and sustained mechanistic target of rapamycin complex 1 signalling. Other notable characteristics of this ‘muscle full’ phenomenon include: (i) it cannot be overcome by proximal intake of additional nutrient signals/substrates regulating MPS; meaning a refractory period exists before a next stimulation is possible, (ii) it is refractory to pharmacological/nutraceutical enhancement of muscle blood flow and thus is not induced by muscle hypo-perfusion, (iii) it manifests independently of whether protein intake occurs in a bolus or intermittent feeding pattern, and (iv) it does not appear to be dependent on protein dose per se. Instead, the main factor associated with altering muscle full is physical activity. For instance, when coupled to protein intake, resistance exercise delays the muscle full set-point to permit additional use of available EAA for MPS to promote muscle remodelling/growth. In contrast, ageing is associated with blunted MPS responses to protein/exercise (anabolic resistance), while physical inactivity (e.g. immobilisation) induces a premature muscle full, promoting muscle atrophy. It is crucial that in catabolic scenarios, anabolic strategies are sought to mitigate muscle decline. This review highlights regulatory protein turnover interactions by dietary protein, exercise, ageing and physical inactivity.
This study estimates the maximum price at which mesenchymal stem cell (MSC) therapy is deemed cost-effective for septic shock patients and identifies parameters that are most important in making treatment decisions.
We developed a probabilistic Markov model according to the sepsis care trajectory to simulate costs and quality-adjusted life years (QALYs) of septic shock patients receiving either MSC therapy or usual care over their lifetime. We calculated the therapeutic headroom by multiplying the gains attributable to MSCs with willingness-to-pay (WTP) threshold and derived the maximum reimbursable price (MRP) from the expected net monetary benefit and savings attributable to MSCs. We performed scenario analyses to assess the impact of changes to assumptions on the study findings. A value of information analysis is performed to identify parameters with greatest impact on the uncertainty around the cost-effectiveness of MSC therapy.
At a WTP threshold of $50,000 per QALY, the therapeutic headroom and MRP of MSC therapy were $20,941 and $16,748, respectively; these estimates increased with the larger WTP values and the greater impact of MSCs on in-hospital mortality and hospital discharge rates. The parameters with greatest information value were MSC's impact on in-hospital mortality and the baseline septic shock in-hospital mortality.
At a common WTP of $50,000/QALY, MSC therapy is deemed to be economically attractive if its unit cost does not exceed $16,748. This ceiling price can be increased to $101,450 if the therapy significantly reduces both in-hospital mortality and increases hospital discharge rates.
Advanced imaging techniques are enhancing research capacity focussed on the developmental origins of adult health and disease (DOHaD) hypothesis, and consequently increasing awareness of future health risks across various subareas of DOHaD research themes. Understanding how these advanced imaging techniques in animal models and human population studies can be both additively and synergistically used alongside traditional techniques in DOHaD-focussed laboratories is therefore of great interest. Global experts in advanced imaging techniques congregated at the advanced imaging workshop at the 2019 DOHaD World Congress in Melbourne, Australia. This review summarizes the presentations of new imaging modalities and novel applications to DOHaD research and discussions had by DOHaD researchers that are currently utilizing advanced imaging techniques including MRI, hyperpolarized MRI, ultrasound, and synchrotron-based techniques to aid their DOHaD research focus.
The aims of this study were to evaluate changes in inflammatory and oxidative stress levels following treatment with N-acetylcysteine (NAC) or mitochondrial-enhancing agents (CT), and to assess the how these changes may predict and/or moderate clinical outcomes primarily the Montgomery-Åsberg Depression Rating Scale (MADRS).
This study involved secondary analysis of a placebo-controlled randomised trial (n = 163). Serum samples were collected at baseline and week 16 of the clinical trial to determine changes in Interleukin-6 (IL-6) and total antioxidant capacity (TAC) following adjunctive CT and/or NAC treatment, and to explore the predictability of the outcome or moderator effects of these markers.
In the NAC-treated group, no difference was observed in serum IL-6 and TAC levels after 16 weeks of treatment with NAC or CT. However, results from a moderator analysis showed that in the CT group, lower IL-6 levels at baseline was a significant moderator of MADRS χ2 (df) = 4.90, p = 0.027) and Clinical Global Impression-Improvement (CGI-I, χ2 (df) = 6.28 p = 0.012). In addition, IL-6 was a non-specific but significant predictor of functioning (based on the Social and Occupational Functioning Assessment Scale (SOFAS)), indicating that individuals with higher IL-6 levels at baseline had a greater improvement on SOFAS regardless of their treatment (p = 0.023).
Participants with lower IL-6 levels at baseline had a better response to the adjunctive treatment with the mitochondrial-enhancing agents in terms of improvements in MADRS and CGI-I outcomes.
Metabolic resistances to atrazine (atz-R) and mesotrione (meso-R) occur in several waterhemp [Amaranthus tuberculatus (Moq.) Sauer] populations in the United States. Interestingly, although metabolic atz-R but mesotrione-sensitive A. tuberculatus populations have been reported, an Amaranthus population has not been confirmed as meso-R but atrazine-sensitive, implying an association between these traits. Experiments were designed to investigate whether the single gene conferring metabolic atz-R plays a role in meso-R. An F2 population was generated from a multiple herbicide–resistant A. tuberculatus population from McLean County, IL (MCR). A cross was made between a known meso-R male clone (MCR-6) and a herbicide-sensitive female clone from Wayne County, IL (WCS-2) to develop an F1 population. Survival of MCR-6 plants following atrazine POST treatment (14.4 kg ha−1) indicated the male parent was homozygous atz-R. F1 plants were intermated to obtain a segregating pseudo-F2 population. Dose–response and metabolic studies conducted with mesotrione using F1 plants indicated intermediate biomass reductions and metabolic rates compared with MCR-6 and WCS. F2 plants were initially treated with either mesotrione (260 g ha−1) or atrazine (2 kg ha−1) POST, and after 21 d of recovery, vegetative clones from surviving resistant plants were subsequently treated with the other herbicide. When mesotrione was applied first, the meso-R frequency was 8.2%, and when atrazine was applied first, the atz-R frequency was 75%. However, the meso-R frequency increased to 16.5% following preselection for atz-R, and 100% of surviving meso-R plants were atz-R. Our findings indicate that the gene conferring metabolic atz-R is also involved with the meso-R trait within the population tested.
Research suggests that buprenorphine may possess antidepressant activity. The Beck Depression Inventory was completed at baseline and 3 months by heroin dependent subjects receiving either buprenorphine or methadone maintenance as part of a larger, pre-existing, double blind trial conducted by NDARC (Australia). Depressive symptoms improved in all subjects, with no difference between methadone and buprenorphine groups, suggesting no differential benefit on depressive symptoms for buprenorphine compared to methadone.
Prognostic staging is one of the most important current psychiatrical challenges.
Bipolar prognostic factors must be identified to assist in staging.
To assess prognostic factors, to describe any correlation with the disease outcome and to recommend that psychiatrists assess bipolar patients, determining their stage of disease in order to identify possible high-risk groups of patients.
We collected data from the clinical notes of 70 bipolar outpatients seen at the initial psychiatric assessment clinic about socio-demographic and clinical factors.
The sample comprised 16 bipolar I (22.9%) and 54 bipolar II (77.1%) outpatients; 60.9% reported anxiety, 71.7 % mixed state features and 72.7% rapid cycling. A comparison between 12 prognostic factors found that only the correlations between current illicit drug use/previous illicit drug use, current alcohol use/previous alcohol use, and current illicit drug use/anxiety were statistically significant; the correlation between previous illicit drug use/previous alcohol use, previous alcohol use/family history and mixed state features/anxiety were almost significant.
17 patients were assigned to a care coordinator; we found no statistically significant differences between the patients with or without a care coordinator on the basis of the presence of 12 possible prognostic factors.
In our sample, some patients were found not to have information available so we suggest that a questionnaire to remind clinicians of potentially useful information would be helpful to aid in prognostication. Specific features of the disease (family history, age at onset, features of depressive episodes and mixed state, rapid cycling) may be highlighted.
The Health of the Nation Outcomes Scales (HoNOS) has been widely used as an outcome measure in UK mental health settings for the past decade. The data-set gathered provides a unique opportunity to evaluate the effectiveness of the totality of mental healthcare in ‘real-world’ conditions; much of our clinical evidence currently comes from highly parameterised clinical trials investigating single interventions in highly selected patients.
To examine all outcomes measured by HoNOS for a range of diagnostic groups, evaluate the influence of patient demographics on those outcomes, and observe changes in patient groups over time.
Here we show the data from 6813 adult patients treated in Cambridgeshire between 2012 and 2017. Patients were split into three diagnostic groups: psychosis, non-psychosis and organic. Changes in HoNOS scores from initial assessment to discharge were tested and regressions were used to evaluate the influence of age, gender and ethnicity on the changes, as well as to model changes in the severity of initial presenting symptoms with time.
HoNOS scores significantly improve after treatment for psychotic, non-psychotic and organic conditions in adults and older adults. Age, but not gender or ethnicity, influenced change in HoNOS scores. Patients entering secondary mental health services had increased initial HoNOS scores over time.
The UK repository of HoNOS scores provides a significant and relatively underutilised resource that can be exploited to gain insights into mental illness and treatment effectiveness. This is likely to have many applications, including influencing the commissioning of services.
Consistent with pathophysiological models of psychosis, temporal disturbances in schizophrenia spectrum populations may reflect abnormal cortical (e.g. prefrontal cortex) and subcortical (e.g. striatum) cerebellar connectivity. However, few studies have examined associations between cerebellar connectivity and timing dysfunction in psychosis populations, and none have been conducted in youth at clinical high-risk (CHR) for psychosis. Thus, it is currently unknown if impairments in temporal processes are present in CHR youth or how they may be associated with cerebellar connectivity and worsening of symptoms.
A total of 108 (56 CHR/52 controls) youth were administered an auditory temporal bisection task along with a resting state imaging scan to examine cerebellar resting state connectivity. Positive and negative symptoms at baseline and 12 months later were also quantified.
Controlling for alcohol and cannabis use, CHR youth exhibited poorer temporal accuracy compared to controls, and temporal accuracy deficits were associated with abnormal connectivity between the bilateral anterior cerebellum and a right caudate/nucleus accumbens striatal cluster. Poor temporal accuracy accounted for 11% of the variance in worsening of negative symptoms over 12 months.
Behavioral findings suggest CHR youth perceive durations of auditory tones as shortened compared to objective time, which may indicate a slower internal clock. Poorer temporal accuracy in CHR youth was associated with abnormalities in brain regions involved in an important cerebellar network implicated in prominent pathophysiological models of psychosis. Lastly, temporal accuracy was associated with worsening of negative symptoms across 12 months, suggesting temporal dysfunction may be sensitive to illness progression.
Rehabilitation of memory after stroke remains an unmet need. Telehealth delivery may overcome barriers to accessing rehabilitation services.
We conducted a non-randomized intervention trial to investigate feasibility and effectiveness of individual telehealth (internet videoconferencing) and face-to-face delivery methods for a six-week compensatory memory rehabilitation program. Supplementary analyses investigated non-inferiority to an existing group-based intervention, and the role of booster sessions in maintaining functional gains. The primary outcome measure was functional attainment of participants’ goals. Secondary measures included subjective reports of lapses in everyday memory and prospective memory, reported use of internal and external memory strategies, and objective measures of memory functioning.
Forty-six stroke survivors were allocated to telehealth and face-to-face intervention delivery conditions. Feasibility of delivery methods was supported, and participants in both conditions demonstrated treatment-related improvements in goal attainment, and key subjective outcomes of everyday memory, and prospective memory. Gains on these measures were maintained at six-week follow-up. Short-term gains in use of internal strategies were also seen. Non-inferiority to group-based delivery was established only on the primary measure for the telehealth delivery condition. Booster sessions were associated with greater maintenance of gains on subjective measures of everyday memory and prospective memory.
This exploratory study supports the feasibility and potential effectiveness of telehealth options for remote delivery of compensatory memory skills training after a stroke. These results are also encouraging of a role for booster sessions in prolonging functional gains over time.
The C677T polymorphism in the folate metabolising enzyme methylenetetrahydrofolate reductase (MTHFR) is associated with hypertension. Riboflavin acts as a cofactor for MTHFR in one-carbon metabolism which generates methyl groups for utilisation in important biological reactions such as DNA methylation. Supplementation with riboflavin has previously been shown to lower blood pressure in individuals with the MTHFR 677TT genotype. The mechanism regulating this gene-nutrient interaction is currently unknown but may involve aberrant DNA methylation which has been implicated hypertension.
The aims of this study were to examine DNA methylation of hypertension-related genes in adults stratified by MTHFR C677T genotype and the effect of riboflavin supplementation on DNA methylation of these genes in individuals with the MTHFR 677TT genotype.
Materials and Methods:
We measured DNA methylation using pyrosequencing in a set of candidate genes associated with hypertension including angiotensin II receptor type 1 (AGTR1), G nucleotide binding protein subunit alpha 12 (GNA12), insulin-like growth factor 2 (IGF2) and nitric oxide synthase 3 (NOS3). Stored peripheral blood leukocyte samples from participants previously screened for the MTHFR C677T genotype who participated in targeted randomised controlled trials (1.6mg/d riboflavin or placebo for 16 weeks) at Ulster University were accessed for this analysis (n = 120).
There were significant differences in baseline average methylation between MTHFR CC and TT genotypes at NOS3 (p = 0.026) and AGTR1 (p = 0.045) loci. Riboflavin supplementation in the TT genotype group resulted in altered average methylation at IGF2 (p = 0.025) and CpG site-specific alterations at the AGTR1 and GNA12 loci.
DNA methylation at genes related to hypertension were significantly different in individuals stratified by MTHFR genotype group. Furthermore, in MTHFR 677TT genotype individuals, there were concurrent alterations in DNA methylation at genes linked to hypertension in response to riboflavin supplementation. This is the largest study to date to demonstrate an interaction between DNA methylation of hypertension-related genes and riboflavin supplementation in adults with the MTHFR 677TT genotype. Further work using a genome-wide approach is required to better understand the role of riboflavin in altering DNA methylation in these genetically at-risk individuals.
American Indians experience substantial health disparities relative to the US population, including vascular brain aging. Poorer cognitive test performance has been associated with cranial magnetic resonance imaging findings in aging community populations, but no study has investigated these associations in elderly American Indians.
We examined 786 American Indians aged 64 years and older from the Cerebrovascular Disease and its Consequences in American Indians study (2010–2013). Cranial magnetic resonance images were scored for cortical and subcortical infarcts, hemorrhages, severity of white matter disease, sulcal widening, ventricle enlargement, and volumetric estimates for white matter hyperintensities (WMHs), hippocampus, and brain. Participants completed demographic, medical history, and neuropsychological assessments including testing for general cognitive functioning, verbal learning and memory, processing speed, phonemic fluency, and executive function.
Processing speed was independently associated with the presence of any infarcts, white matter disease, and hippocampal and brain volumes, independent of socioeconomic, language, education, and clinical factors. Other significant associations included general cognitive functioning with hippocampal volume. Nonsignificant, marginal associations included general cognition with WMH and brain volume; verbal memory with hippocampal volume; verbal fluency and executive function with brain volume; and processing speed with ventricle enlargement.
Brain-cognition associations found in this study of elderly American Indians are similar to those found in other racial/ethnic populations, with processing speed comprising an especially strong correlate of cerebrovascular disease. These findings may assist future efforts to define opportunities for disease prevention, to conduct research on diagnostic and normative standards, and to guide clinical evaluation of this underserved and overburdened population.
Preferential dissolution of the biogenic carbonate polymorph aragonite promotes preservational bias in shelly marine faunas. While field studies have documented the impact of preferential aragonite dissolution on fossil molluscan diversity, its impact on regional and global biodiversity metrics is debated. Epicontinental seas are especially prone to conditions that both promote and inhibit preferential dissolution, which may result in spatially extensive zones with variable preservation. Here we present a multifaceted evaluation of aragonite dissolution within the Late Cretaceous Western Interior Seaway of North America. Occurrence data of mollusks from two time intervals (Cenomanian/Turonian boundary, early Campanian) are plotted on new high-resolution paleogeographies to assess aragonite preservation within the seaway. Fossil occurrences, diversity estimates, and sampling probabilities for calcitic and aragonitic fauna were compared in zones defined by depth and distance from the seaway margins. Apparent range sizes, which could be influenced by differential preservation potential of aragonite between separate localities, were also compared. Our results are consistent with exacerbated aragonite dissolution within specific depth zones for both time slices, with aragonitic bivalves additionally showing a statistically significant decrease in range size compared with calcitic fauna within carbonate-dominated Cenomanian–Turonian strata. However, we are unable to conclusively show that aragonite dissolution impacted diversity estimates. Therefore, while aragonite dissolution is likely to have affected the preservation of fauna in specific localities, time averaging and instantaneous preservation events preserve regional biodiversity. Our results suggest that the spatial expression of taphonomic biases should be an important consideration for paleontologists working on paleobiogeographic problems.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
Experiments were initiated to characterize a waterhemp population (CHR) discovered in a central Illinois corn field after it was not controlled by the 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor topramezone. Field experiments conducted during 2014–2015 indicated that acetolactate synthase (ALS)-, protoporphyrinogen oxidase (PPO)-, photosystem II (PSII)-, and HPPD-inhibiting herbicides and the synthetic auxin 2,4-D did not control the CHR population. Laboratory experiments confirmed target site–based resistance mechanisms to ALS- and PPO-inhibiting herbicides. Herbicide doses required to reduce dry biomass 50% (GR50) were determined in greenhouse dose–response experiments, and indicated 16-fold resistance to the HPPD inhibitor mesotrione, 9.5-fold resistance to the synthetic auxin 2,4-D, and 252-fold resistance to the PSII inhibitor atrazine. Complementary results from field, laboratory, and greenhouse investigations indicate that the CHR population has evolved resistance to herbicides from five sites of action (SOAs): ALS-, PPO-, PSII-, and HPPD-inhibiting herbicides and 2,4-D. Herbicide use history for the field in which CHR was discovered indicates no previous use of 2,4-D.
Objectives: Research has shown that analyzing intrusion errors generated on verbal learning and memory measures is helpful for distinguishing between the memory disorders associated with Alzheimer’s disease (AD) and other neurological disorders, including Huntington’s disease (HD). Moreover, preliminary evidence suggests that certain clinical populations may be prone to exhibit different types of intrusion errors. Methods: We examined the prevalence of two new California Verbal Learning Test-3 (CVLT-3) intrusion subtypes – across-trial novel intrusions and across/within trial repeated intrusions – in individuals with AD or HD. We hypothesized that the encoding/storage impairment associated with medial-temporal involvement in AD would result in a greater number of novel intrusions on the delayed recall trials of the CVLT-3, whereas the executive dysfunction associated with subcortical-frontal involvement in HD would result in a greater number of repeated intrusions across trials. Results: The AD group generated significantly more across-trial novel intrusions than across/within trial repeated intrusions on the delayed cued-recall trials, whereas the HD group showed the opposite pattern on the delayed free-recall trials. Conclusions: These new intrusion subtypes, combined with traditional memory analyses (e.g., recall versus recognition performance), promise to enhance our ability to distinguish between the memory disorders associated with primarily medial-temporal versus subcortical-frontal involvement.