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At least 19 recordsLinked to original sources
PubMed1977

Temporal changes in ovarian ornithine decarboxylase and cyclic AMP in immature rats stimulated by exogenous or endogenous gonadotrophins.

Pregnant mare serum gonadotrophin given intravenously to immature rats caused a maximal (x 70) increase in ornithine decarboxylase activity (ODC) at 3 h; enzyme activity declined to about ten times the control levels by 9 h and a second rise began after about 20 h. Anti-PMSG given 30 min after PMSG reduced the peak response by 70%. Actinomycin D, or cycloheximide, completely prevented an increase in ODC when given with PMSG, but only cycloheximide lowered the enzyme activity when given 18 h later. Ovine FSH plus LH also produced a peak in ODC at 3 h but the activity decreased quickly and by 9 h it was at the control level. Secretion of endogenous FSH and LH, induced by hourly injections of LH releasing hormone (LH-RH) increased ODC to the same extent as did the exogenous hormones; ODC was still higher than in the controls 4 h after the last dose of LH-RH. Increased endogenous levels of FSH and LH did not consistently raise ovarian cyclic AMP content and the increases found were much less than those obtained after injection of PMSG or FSH+LH. The results indicate that increased ODC is induced and maintained by the continual presence of gonadotrophin. The dependence of increased ODC upon increased cyclic AMP cannot be unequivocally determined because of important differences in the timing of the responses and the difficulty in determining biologically significant changes in cyclic AMP.

Age Factors↗
PubMedDate not supplied

Situational stress and temporal changes in self-report and vocal measurements.

Vocal stress levels (using the Psychological Stress Evaluator) the day before and eight days after final examination week for one group (I) of volunteer students were compared with levels of another group (II) without intervening examinations. Time intervals for both groups were identical. Vocal stress was also compared with self-rate anxiety. There was a significant (p less than 0.05) difference in vocal stress for group I when compared to group II, with group I showing a decrease. Mean changes in vocal stress paralleled mean changes (or lack thereof) in self-reported anxiety for both groups. This study suggested that vocal stress, as recorded by the PSE, does depict predictable and self-reported state anxiety which is significantly increased prior to and declines following college final examinations. Data further suggest that the PSE is useful for intervals of days rather than just in terms of minutes and that PSE measures may not be readily altered by acclimatization to the testing situation.

Humans↗
PubMed1976

Blood levels and electroencephalographic effects of diazepam and bromazepam.

Blood levels and electroencephalographic (EEG) data were collected for 2 hr after single oral doses of bromazepam (9 mg), diazepam (10 mg), and placebo in 13 male adult volunteers. Both drugs caused an increase in beta activity (above 13 Hz) and a decrease in alpha activity (9 to 11 Hz) in the EEG. Blood levels of 100 ng/ml of diazepam or 50 ng/ml of bromazepam were associated with significant changes in EEG beta activity. Temporal changes in the EEG after administration of diazepam or bromazepam paralleled development of plasma levels of these drugs. Although a weakly significant correlation was found between measurable diazepam blood levels and amount of increased EEG beta activity, the relationship between measurable bromazepam blood levels and the degree of EEG changes was not significant. Quantitative EEG is a sensitive continuous response measure, useful in defining cerebral activity, response latency, and relative potency of psychoactive benzodiazepines.

Adult↗
PubMed2026

Heterogeneity in Teriflunomide Treatment Arms: A Systematic Review and Meta‑Regression of Randomised Multiple Sclerosis Trials.

BACKGROUND: Teriflunomide is widely used as an active comparator in Phase 3 randomised trials for relapsing multiple sclerosis (RMS). Temporal changes in disease activity within teriflunomide-treated cohorts have not been systematically examined. OBJECTIVES: To assess temporal trends in relapse and disability outcomes across teriflunomide arms of Phase 3 multiple sclerosis (MS) trials and identify predictors of between-trial heterogeneity. METHODS: We performed a systematic review and meta-analysis of Phase 3 randomised controlled trials including a teriflunomide arm. PubMed, Scopus, and ClinicalTrials.gov were searched up to October 2025. Annualised relapse rate (ARR) and 12- and 24-week confirmed disability worsening (CDW) were extracted together with baseline characteristics. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool. Random-effects meta-analyses, meta-regression, and sensitivity analyses were performed. RESULTS: Twelve teriflunomide cohorts from eight trials involving 4,900 adults with RMS were included. ARR ranged from 0.11 to 0.37 with substantial heterogeneity (I2 = 94%). Trial start year was inversely associated with ARR and explained a large proportion of between-study variability in exploratory meta-regression analyses. Confirmed disability worsening outcomes also showed substantial heterogeneity with a weaker trend toward lower event rates in more recent trials. CONCLUSION: Teriflunomide-treated trial populations have shifted toward lower relapse activity over time, and trial start year was the principal predictor of between-trial heterogeneity in ARR in exploratory analyses. These findings most plausibly reflect evolving recruitment and diagnostic practices rather than changes in drug efficacy. Accounting for these temporal dynamics is essential when interpreting outcomes from RMS trial using teriflunomide as comparator.

Humans↗
PubMed2025

Antimicrobial resistance among Gram-negative agents of bacteraemia in the UK and Ireland: trends from 2001 to 2019.

OBJECTIVES: The BSAC Bacteraemia Resistance Surveillance Programme collected isolates from UK and Irish hospitals for central testing. Concurrent UKHSA surveillance collected English hospitals' own susceptibility data. Results were reviewed and compared. METHODS: The BSAC surveillance collected fixed quotas of isolates per site annually from 2001 to 2019. MIC testing was by BSAC agar dilution. Resistance mechanisms were investigated by synergy tests, interpretive reading and PCR. The UKHSA seeks data on all bacteraemia isolates in England. RESULTS: For Escherichia coli, which now causes >30% of all bacteraemias, there were marked early (2002-06) rises in resistance to cephalosporins, fluoroquinolones and gentamicin, followed by small falls, stabilization, then from around 2015, very slow rises, with similar patterns seen for Klebsiella pneumoniae. Most cephalosporin resistance in these two species involved ESBLs, principally CTX-M types. Both species had frequent co-amoxiclav resistance. Cephalosporin resistance-mostly AmpC-mediated-declined in Enterobacter and Serratia spp., as did fluoroquinolone resistance, likely reflecting reduced use and selection pressure. Proteeae showed few changes; increasing dominance of Proteus mirabilis in the BSAC collection was not confirmed by the UKHSA dataset. Resistance in Pseudomonas aeruginosa was uncommon and showed little temporal change in either dataset. Carbapenemases remained extremely rare in all species. Newer and developmental agents covered many resistance types, but none covered all types. CONCLUSIONS: Except for early rises of cephalosporin, fluoroquinolone and gentamicin resistance in E. coli and K. pneumoniae, there was little evidence for rising resistance and some evidence of declining resistance, notably in species where it predominantly involves AmpC derepression.

Humans↗
PubMed1978

[Measurements of storage-induced morphologic changes in preserved blood by means of light scattering].

This study is concerned with changes in diffuse backscattering of white light caused by laminarly streaming or resting banked blood stored for periods up to 7 weeks. The most pronounced changes, i.e. a steep rise of scattering intensity, were found at the beginning of storage. Under streaming conditions such as resulting in a maximum of backscattering and effective disaggregation of rouleaux the temporal changes of scattering intensity obviously were not simply related to morphological properties of the blood. In addition, there was considerable individual variation in the amount of backscattering from various preserves. This invalidates an assessment of banked blood by means of light scattering by a single-data type measurement.

Blood Preservation↗
PubMed2026

Evolutionary history of Aotearoa New Zealand's extinct mātuhituhi | bush wren.

The reconstruction of ecosystem responses to past climate change has historically focused on large vertebrates. In contrast, small vertebrates with potentially stricter habitat preferences have been neglected in ancient DNA studies despite their potential utility as proxies for inferring geographic and temporal changes in habitat. Aotearoa New Zealand's acanthisittid wrens are a speciose group of tiny perching birds, including the mātuhituhi | bush wren (Xenicus longipes ssp.). Despite its relatively recent extinction in the 1970s, very little is known about this enigmatic bird. Here we sequence mitochondrial genomes and nuclear ultra conserved genomic elements from 32 historical bush wren specimens to reconstruct their evolutionary history. We also genetically sex specimens and reanalyse their plumage to reconstruct aspects of bush wren plumage variation. Our analyses suggest North and South Island bush wren populations diverged 2.6 million years ago when narrowing and closure of Plio-Pleistocene seaways allowed colonisation of new habitats, followed by rapid glaciation-driven diversification of South Island populations 470,000-94,000 years ago. Genetic sexing allowed an accurate reconstruction of ontogenetic, sexual, and geographic variation in plumage. Our multidisciplinary data supports recognition of North and South Island populations as separate species, and the description of a new subspecies X. longipes perditus subsp. nov. This research shows how ecosystems can buffer against the impacts of climate change up to an ecological tipping point, which has important lessons for conservation management in a fast-changing world.

Acanthisittidae↗
PubMed1979

Early effects of corticosteroids on basophils, leukocyte histamine, and tissue histamine.

The comparative effect in 11 atopic subjects of a single intravenous injection of methylprednisolone on sequential studies of blood eosinophils, basophils, leukocyte sensitivity to antigen for histamine release, leukocyte histamine content, and skin histamine was examined. No significant changes occurred in any parameter after placebo treatment. In contrast, 4 hr after intravenous treatment with steroid there were significant decreases in mean eosinophil counts (-95%), basophil counts (-72%), and histamine content of 1 X 10(7) leukocyte samples (-62%). Temporal changes in the latter paralleled alterations in circulating basophil levels. No significant changes occured in the antigen histamine release sensitivity, or the total skin histamine. Studies over a longer period after steroids in 4 subjects showed eosinophil and basophil levels at a nadir at 8 hr, remaining suppressed for 24 hr, and returned to pretreatment levels by 72 hr. Results suggest that corticosteroids induce a prominent decrease in leukocyte histamine due to a depletion of basophils without a decrease in histamine content per basophil, and that skin tissue histamine stores remain unchanged by such treatment.

Basophils↗
PubMed2026

Blood Metabolomic Signatures of 1-Hour Glucose Predict Cardiometabolic Risk.

BACKGROUND: Elevated 1-hour glucose levels during an oral glucose tolerance test strongly predict type 2 diabetes (T2D) and cardiovascular disease. We investigated whether the fasting blood metabolome predicting 1-hour glucose could be a target for improving β-cell function, long-term glycemic trajectories, and reducing the risks of T2D and coronary heart disease. We also investigated whether plasma microRNAs derived from key metabolic organs regulate changes in a metabolomic risk score (MRS) for predicting 1-hour glucose. METHODS: Untargeted blood metabolomics and a frequently sampled 75-g oral glucose tolerance test were performed in participants from the OmniCarb trial (n=162). In an independent weight-loss dietary intervention trial (POUNDS Lost [Preventing Overweight Using Novel Dietary Strategies]), temporal changes in MRS and plasma microRNAs measured by genome-wide sequencing were analyzed. In addition, associations of MRS at baseline and its 10-year changes with long-term risk of incident T2D and coronary heart disease were prospectively investigated in the NHS (Nurses' Health Study). RESULTS: We created a fasting blood MRS for predicting 1-hour glucose (Pearson r=0.8) and found significant associations with half-day (diurnal) postprandial glucose excursions and insulin secretion after 5-week controlled feeding interventions varying in carbohydrate amount and glycemic index. In the POUNDS Lost trial, diet-induced changes in MRSs were related to 2-year trajectories of glucose metabolism; circulating microRNAs regulating cardiometabolic abnormalities were pivotal factors influencing these changes. In the NHS, women in the top 20% of MRS had a multivariate-adjusted relative risk of 3.80 (95% CI, 2.22-6.51) for T2D and 1.48 (95% CI, 1.04-2.12) for coronary heart disease compared with those in the lowest 20%. In addition, 10-year increases in plasma metabolites related to 1-hour glucose were linearly associated with a higher risk of T2D. CONCLUSIONS: Our findings indicate that fasting blood metabolomic signatures predicting elevated 1-hour glucose reflect disease pathophysiology and could be targets for preventing T2D and coronary heart disease.

blood glucose↗
PubMed1979

Changes in proline synthetic and degradative enzymes during matrix-induced cartilage and bone formation.

Proline biosynthetic and degradative enzymes are unevenly distributed in differentiated mammalian tissues. Activities of the synthetic enzymes are relatively high in collagenous tissues, whereas activities of the degradative enzymes are high in noncollagenous tissues. In order to further characterize tissue-specific proline biosynthesis and degradation, we have determined proline enzyme activities during cartilage and bone formation induced by demineralized bone matrix. We can thus follow temporal changes in enzyme activity in a single tissue as different cell types develop. Ornithine aminotransferase and pyrroline-5-carboxylate reductase have peaks of activity which correlate with maximal type II collagen synthesis by chondrocytes. Both enzymes also are active during bone formation. In contrast, proline oxidase and pyrroline-5-carboxylate dehydrogenase are present at low levels and do not change as new cell types appear. Arginase activity peaks during the first 3 days and then rapidly decreases by the time cartilage and bone formation begin. These observations further substantiate the importance of proline biosynthesis in collagenous tissues. The close correlation between ornithine aminotransferase activity and type II collagen synthesis suggests that the pathway from ornithine to proline may be especially important during formation of type II collagen.

Animals↗
PubMed2025

Influence of antimicrobial consumption (AMC) on the detection of antimicrobial resistance genes (ARGs) in urban wastewater.

BACKGROUND: Antimicrobial resistance (AMR) is a global health threat, causing over 1.27 million deaths annually and linked to an additional 4.95 million. AMR transmission occurs beyond clinical settings, with wastewater serving as a sentinel of community-level spread. This study investigated how temporal changes in antimicrobial consumption (AMC) correlate with the prevalence of antimicrobial resistance genes (ARGs) in wastewater, using wastewater surveillance (WS) to monitor resistance trends in Quebec, Canada. METHODOLOGY: AMC data (January 2019-May 2023) were obtained from the Institut National de Sant&#xe9; Publique du Qu&#xe9;bec (INSPQ) under a license from IQVIA Solutions Canada Inc. Wastewater samples (September 2020-September 2022) were obtained from three WWTPs and screened for 11 ARGs, including blaTEM, blaSHV, blaCTX-M, blaNDM, blaOXA-1/30, qnrA, qnrB, mphE, and mefA. Analyses assessed temporal and spatial associations between AMC and ARGs. RESULTS: Total prescriptions declined from 537 to 392 per 1000 inhabitants between 2019 and 2020 (-27&#xa0;%), likely due to the impact of the COVID-19 pandemic. This shift created a contrast that allowed us to better capture the signal of AMC through the noise in wastewater composition. &#x3b2;-lactams, macrolides, and fluoroquinolones were the most prescribed classes. ARGs were consistently detected in all 41 samples, with macrolide resistance genes being the most abundant. Strong correlations were observed between AMC and ARG prevalence in wastewater, particularly for &#x3b2;-lactams and fluoroquinolones (Spearman R&#xa0;=&#xa0;0.80 and 0.81, p&#xa0;<&#xa0;0.05). Spatial patterns showed uniform AMC but variable ARG levels. CONCLUSIONS: Our study highlights the correlation between AMC and ARG. WS shows promise for real-time AMR monitoring.

Wastewater↗
PubMed1975

Retention and redistribution of proteins in mammalian nerve fibres by axoplasmic transport.

Fast axoplasmic transport is characterized by a crest of labelled activity moving down nerve fibres after injection of the L7 dorsal root ganglion with the amino acid precursor (3H) leucine, the crest followed by a plateau which represents in part a later egress of labelled components from compartments in the cell bodies and in part materials left behind the advancing crest. 2. after making ligations just below the ganglia at different times after injection of the precursor, a small downward slope of locally retained activity of incorporated materials is seen in the plateau remaining in the nerves. The slope becomes changed to a horizontal level when in addition a distal ligation is made as a result of the redistribution of labelled materials within the doubly ligated nerve segments. 3. the outlfow pattern at later times, at a day and longer after injection, shows an additional spread of activity from the cell body region. The pattern of outflow gradually levels off at later times as additions of activity are made to the more distal part of the nerves. The activity retained in the nerves becomes less free to become redistributed in the course of several days. 4. The temporal changes in the outflow patterns can be accounted for by the local retention and redistribution of the labelled materials within the fibres. Later additions of labelled materials compartmented in the cell bodies also contribute to the later pattern of outflow. A "unitary" view for fast and slow transport is presented based on the transport filament hypothesis earlier proposed to account for fast axoplasmic transport.

Animals↗
PubMed2026

Transient acoustic stimulation induces time-dependent synaptic remodeling and enhancement of auditory nerve output after threshold recovery.

BACKGROUND: Acoustic stress can alter cochlear function even in the absence of permanent threshold elevation; however, synaptic consequences of transient acoustic stimulation remain incompletely understood. OBJECTIVE: This study aimed to investigate whether transient acoustic stimulation induces changes in the auditory nerve output and cochlear ribbon synapse morphology following hearing threshold recovery. METHODS: Young adult CBA/CaJ mice were exposed to band-limited acoustic stimulation (45-2,000&#xa0;Hz, 95&#xa0;dB SPL, 2&#xa0;h). Auditory brainstem responses (ABRs), hair cell and spiral ganglion neuron survival, and synaptic morphology were evaluated before exposure and up to 2&#xa0;weeks post-exposure. RESULTS: ABR thresholds were transiently elevated immediately after exposure but largely recovered by 1&#xa0;day post-exposure. In contrast, ABR wave I amplitudes significantly increased after threshold recovery across multiple test frequencies. Ribbon-associated puncta in both inner and outer hair cell regions exhibited biphasic temporal changes, with an initial decrease immediately after exposure followed by an increase at 1&#xa0;day post-exposure. The ribbon-associated punctal area also increased after exposure and remained elevated at later post-exposure time points. No significant loss of hair cells or spiral ganglion neurons was observed. Exploratory genomic analysis suggested enrichment of pathways related to metabolic defense and cellular stress responses. CONCLUSIONS: Transient acoustic stimulation induces time-dependent synaptic remodeling and enhancement of peripheral auditory nerve output without overt cellular degeneration. These findings support a model in which early cochlear responses to acoustic perturbation include adaptive synaptic plasticity and gain regulation, extending current concepts of noise-induced cochlear change beyond irreversible synaptic loss.

Animals↗