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Nuclear Medicine Review. Central &... 2022Thyroid cancer is the most common malignant disease of the endocrine system and radioiodine therapy (RAIT) is still very often used, resulting in patients staying...
BACKGROUND
Thyroid cancer is the most common malignant disease of the endocrine system and radioiodine therapy (RAIT) is still very often used, resulting in patients staying hospitalized for a few days alone and without visitors, augmenting their stress and discomfort. Our objective was to find simple ways of improving RAIT patients' feelings and perceived quality of the nuclear medicine (NM) department services.
MATERIAL AND METHODS
We designed a two-year study in order to enhance RAIT patients' perceived quality of the nuclear medicine (NM) department services and expectations' fulfillment. A questionnaire was used in order to capture patients' perceived quality and expectations from their RAIT.
RESULTS
549 replies were collected. Many intrinsic and extrinsic determinants were found to be positively or negatively related to the perceived quality and fulfillment of patients' expectations of receiving RAIT. A 1% increase could be achieved by spending 110 € per RAIT room.
CONCLUSIONS
In this article, we present some easily implemented changes in both personnel behavior and room amenities that could, at least in theory and based on our results, offer a 37.9% improvement in RAIT patients' perceived quality and expectations' fulfillment at a cost of 4169 €.
Topics: Humans; Iodine Radioisotopes; Motivation; Radionuclide Imaging; Thyroid Neoplasms
PubMed: 36047293
DOI: 10.5603/NMR.a2022.0031 -
Proceedings of the National Academy of... Feb 2021Voltage sensing with genetically expressed optical probes is highly desirable for large-scale recordings of neuronal activity and detection of localized voltage signals...
Voltage sensing with genetically expressed optical probes is highly desirable for large-scale recordings of neuronal activity and detection of localized voltage signals in single neurons. Most genetically encodable voltage indicators (GEVI) have drawbacks including slow response, low fluorescence, or excessive bleaching. Here we present a dark quencher GEVI approach (dqGEVI) using a Förster resonance energy transfer pair between a fluorophore glycosylphosphatidylinositol-enhanced green fluorescent protein (GPI-eGFP) on the outer surface of the neuronal membrane and an azo-benzene dye quencher (D3) that rapidly moves in the membrane driven by voltage. In contrast to previous probes, the sensor has a single photon bleaching time constant of ∼40 min, has a high temporal resolution and fidelity for detecting action potential firing at 100 Hz, resolves membrane de- and hyperpolarizations of a few millivolts, and has negligible effects on passive membrane properties or synaptic events. The dqGEVI approach should be a valuable tool for optical recordings of subcellular or population membrane potential changes in nerve cells.
Topics: Action Potentials; Animals; Fluorescence Resonance Energy Transfer; Fluorescent Dyes; Green Fluorescent Proteins; HEK293 Cells; Humans; Membrane Potentials; Memory; Neurons
PubMed: 33531364
DOI: 10.1073/pnas.2020235118 -
Molecules (Basel, Switzerland) Jun 2024This research aimed to encapsulate the fruit extract to increase its stability for incorporation into food products such as jelly or jelly powder. After extraction, the...
This research aimed to encapsulate the fruit extract to increase its stability for incorporation into food products such as jelly or jelly powder. After extraction, the nanoliposomes containing the extract were prepared in ratios of 60-0, 50-10, 40-20, and 30-30 lecithin-to-cholesterol. The effects of lecithin-to-cholesterol concentrations on the related parameters were then evaluated. The results showed that the average particle size was in the range of 95.05 to 164.25 nm, and with an increasing cholesterol concentration, the particle size of the nanoliposomes increased. The addition of cholesterol increased the zeta potential from -60.40 to -68.55 millivolt. Furthermore, cholesterol led to an increase in encapsulation efficiency, and even improved the stability of phenolic compounds loaded in nanoliposomes during storage time. Fourier transform infrared (FTIR) spectroscopy confirmed the successful loading of the extract. Field emission scanning electron microscopy (FE-SEM) analysis revealed nano-sized spherical and almost-elliptical liposomes. For jelly powders, the water solubility index ranged from 39.5 to 43.7% ( > 0.05), and the hygroscopicity values ranged between 1.22 and 9.36 g/100 g ( < 0.05). In conclusion, nanoencapsulated extract displayed improved stability and can be used in jelly preparation without any challenge or unfavorable perception.
Topics: Liposomes; Plant Extracts; Capparis; Particle Size; Nanoparticles; Lecithins; Cholesterol; Drug Compounding; Spectroscopy, Fourier Transform Infrared; Solubility
PubMed: 38930869
DOI: 10.3390/molecules29122804 -
Science (New York, N.Y.) May 2023Discovery of earth-abundant electrocatalysts to replace iridium for the oxygen evolution reaction (OER) in a proton exchange membrane water electrolyzer (PEMWE)...
Discovery of earth-abundant electrocatalysts to replace iridium for the oxygen evolution reaction (OER) in a proton exchange membrane water electrolyzer (PEMWE) represents a critical step in reducing the cost for green hydrogen production. We report a nanofibrous cobalt spinel catalyst codoped with lanthanum (La) and manganese (Mn) prepared from a zeolitic imidazolate framework embedded in electrospun polymer fiber. The catalyst demonstrated a low overpotential of 353 millivolts at 10 milliamperes per square centimeter and a low degradation for OER over 360 hours in acidic electrolyte. A PEMWE containing this catalyst at the anode demonstrated a current density of 2000 milliamperes per square centimeter at 2.47 volts (Nafion 115 membrane) or 4000 milliamperes per square centimeter at 3.00 volts (Nafion 212 membrane) and low degradation in an accelerated stress test.
PubMed: 37167381
DOI: 10.1126/science.ade1499 -
Seminars in Ophthalmology May 2020The aim of this study was to document diurnal changes in intraocular pressure (IOP) in uveitic glaucoma (UG) and compare it with primary open angle glaucoma (POAG)... (Comparative Study)
Comparative Study
PURPOSE
The aim of this study was to document diurnal changes in intraocular pressure (IOP) in uveitic glaucoma (UG) and compare it with primary open angle glaucoma (POAG) patients.
METHODS
Eight patients with UG and seven patients with POAG were included in this study. The patients were matched for age, gender, and glaucoma medications. None of the patients experienced angle closure, uveitis attack, and ocular surgery, and were not under steroid or immunomodulatory therapy within the last three months. The 24-hour IOP fluctuations were recorded with the help of a contact lens sensor (Sensimed Triggerfish ®, Switzerland). The diurnal IOP fluctuations were modeled with best-fit lines and statistical comparisons between the longitudinal responses of the two groups were determined with nonlinear regression.
RESULTS
The comparison of mean 24-hour contact lens sensor (CLS) amplitudes revealed a significant difference between the fluctuation levels of UG and POAG groups (213 ± 160 millivolt equivalents (mVeq) vs. 162 ± 168 mVeq, respectively = .003). The top level of the best-fit curves was significantly higher in the UG group (266 ± 143 mVeq) compared to the POAG group (159 ± 162 mVeq, < .001). Both curves had their top levels between 5:00 PM and 8:00 AM. The longitudinal regression analysis revealed that the amplitudes of the 24-hour fluctuation waves were significantly different ( = .041).
CONCLUSIONS
This study demonstrated for the first time that the diurnal variation in IOP was significantly higher in UG patients. This difference was also more distinct between 5:00 PM and 8:00 AM clock-hours. The uveitis and glaucoma specialists should consider this potential for higher IOP fluctuations, while tailoring the glaucoma treatment in uveitic patients.
Topics: Adult; Aged; Circadian Rhythm; Cross-Sectional Studies; Female; Follow-Up Studies; Glaucoma; Humans; Intraocular Pressure; Male; Middle Aged; Time Factors; Tonometry, Ocular
PubMed: 32881589
DOI: 10.1080/08820538.2020.1809683 -
Nature Feb 2020Solid-state lithium metal batteries require accommodation of electrochemically generated mechanical stress inside the lithium: this stress can be up to 1 gigapascal for...
Solid-state lithium metal batteries require accommodation of electrochemically generated mechanical stress inside the lithium: this stress can be up to 1 gigapascal for an overpotential of 135 millivolts. Maintaining the mechanical and electrochemical stability of the solid structure despite physical contact with moving corrosive lithium metal is a demanding requirement. Using in situ transmission electron microscopy, we investigated the deposition and stripping of metallic lithium or sodium held within a large number of parallel hollow tubules made of a mixed ionic-electronic conductor (MIEC). Here we show that these alkali metals-as single crystals-can grow out of and retract inside the tubules via mainly diffusional Coble creep along the MIEC/metal phase boundary. Unlike solid electrolytes, many MIECs are electrochemically stable in contact with lithium (that is, there is a direct tie-line to metallic lithium on the equilibrium phase diagram), so this Coble creep mechanism can effectively relieve stress, maintain electronic and ionic contacts, eliminate solid-electrolyte interphase debris, and allow the reversible deposition/stripping of lithium across a distance of 10 micrometres for 100 cycles. A centimetre-wide full cell-consisting of approximately 10 MIEC cylinders/solid electrolyte/LiFePO-shows a high capacity of about 164 milliampere hours per gram of LiFePO, and almost no degradation for over 50 cycles, starting with a 1× excess of Li. Modelling shows that the design is insensitive to MIEC material choice with channels about 100 nanometres wide and 10-100 micrometres deep. The behaviour of lithium metal within the MIEC channels suggests that the chemical and mechanical stability issues with the metal-electrolyte interface in solid-state lithium metal batteries can be overcome using this architecture.
PubMed: 32015545
DOI: 10.1038/s41586-020-1972-y -
Cell Reports Jan 2023The endoplasmic reticulum (ER) is a tortuous organelle that spans throughout a cell with a continuous membrane containing ion channels, pumps, and transporters. It is...
The endoplasmic reticulum (ER) is a tortuous organelle that spans throughout a cell with a continuous membrane containing ion channels, pumps, and transporters. It is unclear if stimuli that gate ER ion channels trigger substantial membrane potential fluctuations and if those fluctuations spread beyond their site of origin. Here, we visualize ER membrane potential dynamics in HEK cells and cultured rat hippocampal neurons by targeting a genetically encoded voltage indicator specifically to the ER membrane. We report the existence of clear cell-type- and stimulus-specific ER membrane potential fluctuations. In neurons, direct stimulation of ER ryanodine receptors generates depolarizations that scale linearly with stimulus strength and reach tens of millivolts. However, ER potentials do not spread beyond the site of receptor activation, exhibiting steep attenuation that is exacerbated by intracellular large conductance K channels. Thus, segments of ER can generate large depolarizations that are actively restricted from impacting nearby, contiguous membrane.
Topics: Animals; Rats; Calcium; Endoplasmic Reticulum; Hippocampus; Membrane Potentials; Neurons; Ryanodine Receptor Calcium Release Channel; Humans; Cell Line
PubMed: 36640310
DOI: 10.1016/j.celrep.2022.111943 -
IEEE Journal of Translational... 2019The electrocardiogram (ECG) plays an important role in the diagnosis of heart diseases. However, most patterns of diseases are based on old datasets and stepwise...
INTRODUCTION
The electrocardiogram (ECG) plays an important role in the diagnosis of heart diseases. However, most patterns of diseases are based on old datasets and stepwise algorithms that provide limited accuracy. Improving diagnostic accuracy of the ECG can be done by applying machine learning algorithms. This requires taking existing scanned or printed ECGs of old cohorts and transforming the ECG signal to the raw digital (time (milliseconds), voltage (millivolts)) form.
OBJECTIVES
We present a MATLAB-based tool and algorithm that converts a printed or scanned format of the ECG into a digitized ECG signal.
METHODS
30 ECG scanned curves are utilized in our study. An image processing method is first implemented for detecting the ECG regions of interest and extracting the ECG signals. It is followed by serial steps that digitize and validate the results.
RESULTS
The validation demonstrates very high correlation values of several standard ECG parameters: PR interval 0.984 +/-0.021 (p-value < 0.001), QRS interval 1+/- SD (p-value < 0.001), QT interval 0.981 +/- 0.023 p-value < 0.001, and RR interval 1 +/- 0.001 p-value < 0.001.
CONCLUSION
Digitized ECG signals from existing paper or scanned ECGs can be obtained with more than 95% of precision. This makes it possible to utilize historic ECG signals in machine learning algorithms to identify patterns of heart diseases and aid in the diagnostic and prognostic evaluation of patients with cardiovascular disease.
PubMed: 32166049
DOI: 10.1109/JTEHM.2019.2949784 -
Translational Vision Science &... Oct 2020The epithelium lining the ocular surface, which includes corneal and conjunctival epithelia, expresses the prosecretory chloride channel cystic fibrosis transmembrane...
PURPOSE
The epithelium lining the ocular surface, which includes corneal and conjunctival epithelia, expresses the prosecretory chloride channel cystic fibrosis transmembrane conductance regulator (CFTR) and the proabsorptive epithelial sodium channel (ENaC). Here, methodology was established to measure the millivolt (mV) potential differences at the ocular surface, called ocular surface potential difference (OSPD), in human subjects produced by ion transport.
METHODS
OSPD was measured in human subjects in which a fluid-filled measuring electrode contacted a fluid pool created by eversion of the lateral lower eyelid, with a reference electrode placed subcutaneously in the forearm. Through the use of a high-impedance voltmeter, OSPD was measured continuously over 10 to 15 minutes in response to a series of perfusate fluid exchanges.
RESULTS
Baseline OSPD (± SEM) in six normal human subjects was -21.3 ± 3.6 mV. OSPD depolarized by 1.7 ± 0.6 mV following the addition of the ENaC inhibitor amiloride, hyperpolarized by 6.8 ± 1.5 mV with a zero chloride solution, and further hyperpolarized by 15.9 ± 1.6 mV following CFTR activation by isoproterenol. The isoproterenol-induced hyperpolarization was absent in two cystic fibrosis subjects lacking functional CFTR. OSPD measurement produced minimal epithelial injury.
CONCLUSIONS
Our results establish the feasibility and safety of OSPD measurement in humans and demonstrate robust CFTR activity, albeit minimal ENaC activity, at the ocular surface. OSPD measurement may be broadly applicable to investigate fluid transport mechanisms and test drug candidates to treat ocular surface disorders.
TRANSLATIONAL RELEVANCE
To the best of our knowledge, this is the first measurement of the electrical potential generated by the ocular surface epithelium in human subjects, offering a new approach to study ocular surface function and health.
Topics: Amiloride; Cystic Fibrosis; Epithelial Sodium Channels; Eye; Humans; Ion Transport; Ocular Physiological Phenomena; Research Subjects
PubMed: 33117611
DOI: 10.1167/tvst.9.11.20 -
Insect Science Nov 2023Culex tarsalis Coquillett (Diptera: Culicidae) mosquitoes are capable of vectoring numerous pathogens affecting public and animal health. Unfortunately, the probing...
Culex tarsalis Coquillett (Diptera: Culicidae) mosquitoes are capable of vectoring numerous pathogens affecting public and animal health. Unfortunately, the probing behaviors of mosquitoes are poorly understood because they occur in opaque tissues. Electropenetrography (EPG) has the potential to elucidate these behaviors by recording the electrical signals generated during probing. We used an AC-DC EPG with variable input resistors (Ri levels) to construct a waveform library for Cx. tarsalis feeding on human hands. Biological events associated with mosquito probing were used to characterize waveforms at four Ri levels and with two electrical current types. The optimal settings for EPG recordings of Cx. tarsalis probing on human hands was an Ri level of 10 Ohms using an applied signal of 150 millivolts alternating current. Waveforms for Cx. tarsalis included those previously observed and associated with probing behaviors in Aedes aegypti L. (Diptera: Culicidae): waveform families J (surface salivation), K (stylet penetration through the skin), L (types 1 and 2, search for a blood vessel/ingestion site), M (types 1 and 2, ingestion), N (type 1, an unknown behavior which may be a resting and digestion phase), and W (withdrawal). However, we also observed variations in the waveforms not described in Ae. aegypti, which we named types L3, M3, M4, and N2. This investigation enhances our understanding of mosquito probing behaviors. It also provides a new tool for the automated calculation of peak frequency. This work will facilitate future pathogen acquisition and transmission studies and help identify new pest and disease management targets.
PubMed: 37942850
DOI: 10.1111/1744-7917.13292