Serotonin-dependent kinetics of bursts of feeding underlie a graded response to food availability

AbstractAnimals integrate physiological and environmental signals to modulate their food uptake. Failure to regulate feeding may have devastating results, including obesity and diabetes, underscoring the importance of understanding its underlying mechanisms. The nematode C. elegans, whose food uptake consists of pumping bacteria from the environment into the gut, provides excellent opportunities for discovering principles of conserved regulatory mechanisms. Here we show that worms implement a graded feeding response to the concentration of environmental bacteria by modulating a commitment to bursts of fast pumping. Using long-term, high-resolution, longitudinal recordings of feeding dynamics under defined conditions, we find that the frequency and duration of pumping bursts increase and the duration of long pauses diminishes in environments richer in bacteria. The bioamine serotonin, a known feeding regulator in metazoa, is required for food-dependent induction of bursts as well as for maintaining their high rate of pumping through two distinct mechanisms. Following this phenotype quantitatively we identify the essential serotonergic neurons and the differential roles of distinct families of serotonin receptors. We propose that regulation of bursts is a conserved mechanism of behavior and motor control.

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Quantitative effects of environmental variation on stomatal anatomy and gas exchange in a grass model

10.1101/2021.11.10.468085 ◽

2021 ◽

Author(s):

Tiago DG Nunes ◽

Magdalena W Slawinska ◽

Heike Lindner ◽

Michael T Raissig

Keyword(s):

Gas Exchange ◽

Anatomical Variation ◽

Brachypodium Distachyon ◽

Carbon Assimilation ◽

Light Response ◽

Gas Analysis ◽

Environmental Signals ◽

Grass Model ◽

Kinetics Of

Stomata are cellular pores on the leaf epidermis that allow plants to regulate carbon assimilation and water loss. Stomata integrate environmental signals to regulate pore apertures and optimize gas exchange to fluctuating conditions. Here, we quantified intraspecific plasticity of stomatal gas exchange and anatomy in response to seasonal variation in Brachypodium distachyon. Over the course of two years we (i) used infrared gas analysis to assess light response kinetics of 120 Bd21-3 wild-type individuals in an environmentally fluctuating greenhouse and (ii) microscopically determined the seasonal variability of stomatal anatomy in a subset of these plants. We observed systemic environmental effects on gas exchange measurements and remarkable intraspecific plasticity of stomatal anatomical traits. To reliably link anatomical variation to gas exchange, we adjusted anatomical gsmax calculations for grass stomatal morphology. We propose that systemic effects and variability in stomatal anatomy should be accounted for in long-term gas exchange studies.

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Serotonin-dependent kinetics of feeding bursts underlie a graded response to food availability in C. elegans

Nature Communications ◽

10.1038/ncomms14221 ◽

2017 ◽

Vol 8 (1) ◽

Cited By ~ 21

Author(s):

Kyung Suk Lee ◽

Shachar Iwanir ◽

Ronen B. Kopito ◽

Monika Scholz ◽

John A. Calarco ◽

...

Keyword(s):

Food Availability ◽

C Elegans ◽

Graded Response ◽

Kinetics Of

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Comparative Labelling and Biokinetic Studies of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn)

Nuklearmedizin ◽

10.1055/s-0037-1620603 ◽

1977 ◽

Vol 16 (01) ◽

pp. 30-35 ◽

Cited By ~ 1

Author(s):

N. Agha ◽

R. B. R. Persson

Keyword(s):

Complex Formation ◽

Significant Influence ◽

Room Temperature ◽

Ph Value ◽

Maximum Activity ◽

Reduction Step ◽

Labelling Yield ◽

Different Temperatures ◽

Kinetics Of

SummaryGelchromatography column scanning has been used to study the fractions of 99mTc-pertechnetate, 99mTcchelate and reduced hydrolyzed 99mTc in preparations of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn). The labelling yield of 99mTc-EDTA(Sn) chelate was as high as 90—95% when 100 μmol EDTA · H4 and 0.5 (Amol SnCl2 was incubated with 10 ml 99mTceluate for 30—60 min at room temperature. The study of the influence of the pH-value on the fraction of 99mTc-EDTA shows that pH 2.8—2.9 gave the best labelling yield. In a comparative study of the labelling kinetics of 99mTc-EDTA(Sn) and 99mTc- DTPA(Sn) at different temperatures (7, 22 and 37°C), no significant influence on the reduction step was found. The rate constant for complex formation, however, increased more rapidly with increased temperature for 99mTc-DTPA(Sn). At room temperature only a few minutes was required to achieve a high labelling yield with 99mTc-DTPA(Sn) whereas about 60 min was required for 99mTc-EDTA(Sn). Comparative biokinetic studies in rabbits showed that the maximum activity in kidneys is achieved after 12 min with 99mTc-EDTA(Sn) but already after 6 min with 99mTc-DTPA(Sn). The long-term disappearance of 99mTc-DTPA(Sn) from the kidneys is about five times faster than that for 99mTc-EDTA(Sn).

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The Effect of Probiotics Supplementation in Maternal-Fetal Care

Current Women s Health Reviews ◽

10.2174/1573404816999200917155108 ◽

2020 ◽

Vol 16 ◽

Author(s):

Mahnaz Mardani ◽

Sadegh Rezapour

Keyword(s):

Diabetes Mellitus ◽

Protective Role ◽

Optimum Dose ◽

Active Living ◽

Maternal Weight Gain ◽

Long Term Effects ◽

Maternal Weight ◽

Human Gut ◽

Obesity And Diabetes

: Pregnancy-related complications can have long-term effects on mother and fetus/child. Microbiome within the human gut is an important factor to maintain optimum health during pregnancy and could possibly reduce the incidence of these complications. Probiotics are active living microorganisms that can provide the host with health benefits such as; immune and hormonal regulatory and metabolic benefits when administered in adequate and optimum dose. Probiotic supplementations also regulate abnormal and unbalanced microflora population that can control the pathogenesis of several diseases like obesity and diabetes. Probiotics also play a protective role in complications like preeclampsia, gestational diabetes mellitus and maternal weight gain and enhance successful outcomes of reproduction. This mini review will thereby summarize the maternal and fetal effects of probiotics during pregnancy.

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Enhanced Seasonal Exchange of CO2 by Northern Ecosystems Since 1960

Science ◽

10.1126/science.1239207 ◽

2013 ◽

Vol 341 (6150) ◽

pp. 1085-1089 ◽

Cited By ~ 221

Author(s):

H. D. Graven ◽

R. F. Keeling ◽

S. C. Piper ◽

P. K. Patra ◽

B. B. Stephens ◽

...

Keyword(s):

Boreal Forests ◽

Atmospheric Carbon Dioxide ◽

Ecosystem Models ◽

The North ◽

Ecological Changes ◽

Term Change ◽

Major Shift ◽

Underlying Mechanisms ◽

Global Carbon

Seasonal variations of atmospheric carbon dioxide (CO2) in the Northern Hemisphere have increased since the 1950s, but sparse observations have prevented a clear assessment of the patterns of long-term change and the underlying mechanisms. We compare recent aircraft-based observations of CO2 above the North Pacific and Arctic Oceans to earlier data from 1958 to 1961 and find that the seasonal amplitude at altitudes of 3 to 6 km increased by 50% for 45° to 90°N but by less than 25% for 10° to 45°N. An increase of 30 to 60% in the seasonal exchange of CO2 by northern extratropical land ecosystems, focused on boreal forests, is implicated, substantially more than simulated by current land ecosystem models. The observations appear to signal large ecological changes in northern forests and a major shift in the global carbon cycle.

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Blood–brain barrier disruption and ventricular enlargement are the earliest neuropathological changes in rats with repeated sub-concussive impacts over 2 weeks

Scientific Reports ◽

10.1038/s41598-021-88854-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bailey Hiles-Murison ◽

Andrew P. Lavender ◽

Mark J. Hackett ◽

Joshua J. Armstrong ◽

Michael Nesbit ◽

...

Keyword(s):

Oxidative Stress ◽

Blood Brain Barrier ◽

Hippocampal Formation ◽

Brain Barrier ◽

Lateral Ventricles ◽

Blood Brain Barrier Disruption ◽

Blood Brain ◽

Brain Barrier Disruption ◽

Underlying Mechanisms

AbstractRepeated sub-concussive impact (e.g. soccer ball heading), a significantly lighter form of mild traumatic brain injury, is increasingly suggested to cumulatively alter brain structure and compromise neurobehavioural function in the long-term. However, the underlying mechanisms whereby repeated long-term sub-concussion induces cerebral structural and neurobehavioural changes are currently unknown. Here, we utilised an established rat model to investigate the effects of repeated sub-concussion on size of lateral ventricles, cerebrovascular blood–brain barrier (BBB) integrity, neuroinflammation, oxidative stress, and biochemical distribution. Following repeated sub-concussion 3 days per week for 2 weeks, the rats showed significantly enlarged lateral ventricles compared with the rats receiving sham-only procedure. The sub-concussive rats also presented significant BBB dysfunction in the cerebral cortex and hippocampal formation, whilst neuromotor function assessed by beamwalk and rotarod tests were comparable to the sham rats. Immunofluorescent and spectroscopic microscopy analyses revealed no significant changes in neuroinflammation, oxidative stress, lipid distribution or protein aggregation, within the hippocampus and cortex. These data collectively indicate that repeated sub-concussion for 2 weeks induce significant ventriculomegaly and BBB disruption, preceding neuromotor deficits.

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In-Situ Annealed Ti3C2Tx MXene Based All-Solid-State Flexible Zn-Ion Hybrid Micro Supercapacitor Array with Enhanced Stability

Nano-Micro Letters ◽

10.1007/s40820-021-00634-2 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

La Li ◽

Weijia Liu ◽

Kai Jiang ◽

Di Chen ◽

Fengyu Qu ◽

...

Keyword(s):

High Energy ◽

High Rate ◽

High Energy Density ◽

Electrochemical Performances ◽

Integrated Electronics ◽

Long Term Stability ◽

Hybrid Supercapacitors ◽

Portable Electronics

AbstractZn-ion hybrid supercapacitors (SCs) are considered as promising energy storage owing to their high energy density compared to traditional SCs. How to realize the miniaturization, patterning, and flexibility of the Zn-ion SCs without affecting the electrochemical performances has special meanings for expanding their applications in wearable integrated electronics. Ti3C2Tx cathode with outstanding conductivity, unique lamellar structure and good mechanical flexibility has been demonstrated tremendous potential in the design of Zn-ion SCs, but achieving long cycling stability and high rate stability is still big challenges. Here, we proposed a facile laser writing approach to fabricate patterned Ti3C2Tx-based Zn-ion micro-supercapacitors (MSCs), followed by the in-situ anneal treatment of the assembled MSCs to improve the long-term stability, which exhibits 80% of the capacitance retention even after 50,000 charge/discharge cycles and superior rate stability. The influence of the cathode thickness on the electrochemical performance of the MSCs is also studied. When the thickness reaches 0.851 µm the maximum areal capacitance of 72.02 mF cm−2 at scan rate of 10 mV s−1, which is 1.77 times higher than that with a thickness of 0.329 µm (35.6 mF cm−2). Moreover, the fabricated Ti3C2Tx based Zn-ion MSCs have excellent flexibility, a digital timer can be driven by the single device even under bending state, a flexible LED displayer of “TiC” logo also can be easily lighted by the MSC arrays under twisting, crimping, and winding conditions, demonstrating the scalable fabrication and application of the fabricated MSCs in portable electronics.

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Remediation of mercury-contaminated soils and sediments using biochar: a critical review

Biochar ◽

10.1007/s42773-021-00087-1 ◽

2021 ◽

Author(s):

Qian Yang ◽

Yongjie Wang ◽

Huan Zhong

Keyword(s):

Health Risks ◽

Contaminated Soils ◽

Functional Materials ◽

Redox Conditions ◽

Existing Problems ◽

Soils And Sediments ◽

Underlying Mechanisms ◽

Biochar Amendment

AbstractThe transformation of mercury (Hg) into the more toxic and bioaccumulative form methylmercury (MeHg) in soils and sediments can lead to the biomagnification of MeHg through the food chain, which poses ecological and health risks. In the last decade, biochar application, an in situ remediation technique, has been shown to be effective in mitigating the risks from Hg in soils and sediments. However, uncertainties associated with biochar use and its underlying mechanisms remain. Here, we summarize recent studies on the effects and advantages of biochar amendment related to Hg biogeochemistry and its bioavailability in soils and sediments and systematically analyze the progress made in understanding the underlying mechanisms responsible for reductions in Hg bioaccumulation. The existing literature indicates (1) that biochar application decreases the mobility of inorganic Hg in soils and sediments and (2) that biochar can reduce the bioavailability of MeHg and its accumulation in crops but has a complex effect on net MeHg production. In this review, two main mechanisms, a direct mechanism (e.g., Hg-biochar binding) and an indirect mechanism (e.g., biochar-impacted sulfur cycling and thus Hg-soil binding), that explain the reduction in Hg bioavailability by biochar amendment based on the interactions among biochar, soil and Hg under redox conditions are highlighted. Furthermore, the existing problems with the use of biochar to treat Hg-contaminated soils and sediments, such as the appropriate dose and the long-term effectiveness of biochar, are discussed. Further research involving laboratory tests and field applications is necessary to obtain a mechanistic understanding of the role of biochar in reducing Hg bioavailability in diverse soil types under varying redox conditions and to develop completely green and sustainable biochar-based functional materials for mitigating Hg-related health risks.

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Endovascular Treatment of Anterior Circulation Aneurysms With the p64 Flow Modulation Device: Mid- and Long-Term Results in 617 Aneurysms From a Single Center

Operative Neurosurgery ◽

10.1093/ons/opaa425 ◽

2021 ◽

Author(s):

Marta Aguilar Pérez ◽

Elina Henkes ◽

Victoria Hellstern ◽

Carmen Serna Candel ◽

Christina Wendl ◽

...

Keyword(s):

Intracranial Aneurysms ◽

High Rate ◽

Long Term Results ◽

Effective Treatment Option ◽

Anterior Circulation ◽

Acute Hemorrhage ◽

Unruptured Aneurysms ◽

Long Term Follow Up

Abstract BACKGROUND Flow diverters have become an important tool in the treatment of intracranial aneurysms, especially when dealing with difficult-to-treat or complex aneurysms. The p64 is the only fully resheathable and mechanically detachable flow diverter available for clinical use. OBJECTIVE To evaluate the safety and effectiveness of p64 for the treatment of intracranial saccular unruptured aneurysms arising from the anterior circulation over a long-term follow-up period. METHODS We retrospectively reviewed our prospectively maintained database to identify all patients who underwent treatment for an intracranial saccular (unruptured or beyond the acute hemorrhage phase) aneurysm arising from the anterior circulation with ≥1 p64 between December 2011 and December 2019. Fusiform aneurysms and dissections were excluded. Aneurysms with prior or concomitant saccular treatment (eg, coiling and clipping) were included. Aneurysms with parent vessel implants other than p64 were excluded. Anatomic features, intraprocedural complications, clinical outcome, as well as clinical and angiographic follow-ups were all recorded. RESULTS In total, 530 patients (388 females; median age 55.9 yr) with 617 intracranial aneurysms met the inclusion criteria. The average number of devices used per aneurysm was 1.1 (range 1-3). Mean aneurysm dome size was 4.8 mm (range 1-27 mm). Treatment-related morbimortality was 2.4%. Early, mid-term, and long-term angiographic follow-up showed complete or near-complete aneurysm occlusion in 76.8%, 89.7%, and 94.5%, respectively. CONCLUSION Treatment of intracranial saccular unruptured aneurysms of the anterior circulation using p64 is a safe and effective treatment option with high rate of occlusion at long-term follow-up and low morbimortality.

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Scaphoid Nonunion Is a Disabling Problem in a Military Population

Hand ◽

10.1177/15589447211003177 ◽

2021 ◽

pp. 155894472110031

Author(s):

Nicholas H. Lake ◽

Rafae Khan ◽

Kyle W. Mombell ◽

Mary Fergus ◽

Dominic Gomez-Leonardelli

Keyword(s):

Functional Outcome ◽

Military Service ◽

Functional Outcomes ◽

High Rate ◽

Scaphoid Nonunion ◽

Military Population ◽

Outcome Scores ◽

The Mean ◽

Return To Duty

Background Scaphoid nonunion can occur in up to 55% of displaced scaphoid fractures. Long-term functional outcomes of this injury are lacking. In addition, no study has published rate of return to active military service after this injury. Our goal was to educate providers and patients on expected functional outcomes and return to duty after treatment of scaphoid nonunion. Methods We conducted a retrospective review of patients who underwent scaphoid nonunion repair at our institution from 2008 to 2017. The primary outcome measures were union rates, return to duty rates, and functional outcome scores obtained by telephone call. A total of 144 patients were included and 40 responded to our call for long-term follow-up. Results A total of 72% of patients achieved union after surgery, 18% required revision surgery, and 74% of patients were able to return to full duty after surgery. However, this number progressively decreased at 1, 2, and 5 years after surgery. At an average of 5.9 years after surgery, the mean Quick Disabilities of the Arm, Shoulder, and Hand (qDASH) score was 23.9. The mean qDASH for patients who achieved union (21.9) was significantly lower than those with persistent nonunion (29.2) ( P = .0115). Conclusion Scaphoid nonunion is a difficult problem in the military. We found a high rate of persistent nonunion often requiring revision to partial or full wrist arthrodesis. In addition, our long-term functional outcome scores demonstrate significant disability after this injury, even when union is achieved. This information can help us better counsel our patients and set expectations after treatment of this injury.

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