- Comparative Evaluation of Tactile Sensation by Electrical and Mechanical Stimulation. [Journal Article]
- ITIEEE Trans Haptics 2016 Sep 05
- An electrotactile display is a tactile interface that provides tactile perception by passing electrical current through the surface of the skin. It is actively used instead of mechanical tactile disp...
An electrotactile display is a tactile interface that provides tactile perception by passing electrical current through the surface of the skin. It is actively used instead of mechanical tactile displays for tactile feedback because of several advantages such as its small and thin size, light weight, and high responsiveness. However, the similarities and differences between these sensations is still not clear. This study directly compares the intensity sensation of electrotactile stimulation to that of mechanical stimulation, and investigates the characteristic sensation of anodic and cathodic stimulation. In the experiment, participants underwent a 30 pps electrotactile stimulus every one second to their middle finger, and were asked to match this intensity by adjusting the intensity of a mechanical tactile stimulus to an index finger. The results showed that anodic stimulation mainly produced vibration sensation, whereas cathodic sensation produced both vibration and pressure sensations. Relatively low pressure sensation was also observed for anodic stimulation but it remains low, regardless of the increasing of electrical intensity.
- Membrane fluidity controls redox-regulated cold stress responses in cyanobacteria. [Journal Article]
- PRPhotosynth Res 2017 Jan 21
- Membrane fluidity is the important regulator of cellular responses to changing ambient temperature. Bacteria perceive cold by the transmembrane histidine kinases that sense changes in thickness of th...
Membrane fluidity is the important regulator of cellular responses to changing ambient temperature. Bacteria perceive cold by the transmembrane histidine kinases that sense changes in thickness of the cytoplasmic membrane due to its rigidification. In the cyanobacterium Synechocystis, about a half of cold-responsive genes is controlled by the light-dependent transmembrane histidine kinase Hik33, which also partially controls the responses to osmotic, salt, and oxidative stress. This implies the existence of some universal, but yet unknown signal that triggers adaptive gene expression in response to various stressors. Here we selectively probed the components of photosynthetic machinery and functionally characterized the thermodynamics of cyanobacterial photosynthetic membranes with genetically altered fluidity. We show that the rate of oxidation of the quinone pool (PQ), which interacts with both photosynthetic and respiratory electron transport chains, depends on membrane fluidity. Inhibitor-induced stimulation of redox changes in PQ triggers cold-induced gene expression. Thus, the fluidity-dependent changes in the redox state of PQ may universally trigger cellular responses to stressors that affect membrane properties.
- Molecular mechanisms and ecological function of far-red light signalling. [Review]
- PCPlant Cell Environ 2017 Jan 19
- Land plants possess the ability to sense and respond to far-red light (700-760 nm), which serves as an important environmental cue. Due to the nature of far-red light, it is not absorbed by chlorophy...
Land plants possess the ability to sense and respond to far-red light (700-760 nm), which serves as an important environmental cue. Due to the nature of far-red light, it is not absorbed by chlorophyll and thus is enriched in canopy shade, and will also penetrate deeper into soil than other visible wavelengths. Far-red light responses include regulation of seed germination, suppression of hypocotyl growth, induction of flowering, and accumulation of anthocyanins, which depend on one member of the phytochrome photoreceptor family, phytochrome A (phyA). Here we review the current understanding of the underlying molecular mechanisms of how plants sense far-red light through phyA, and the physiological responses to this light quality. Light-activated phytochromes act on two primary pathways within the nucleus; suppression of the E3 ubiquitin ligase complex CUL4/DDB1(COP1/SPA) and inactivation of the PIF family of bHLH transcription factors. These pathways integrate with other signal transduction pathways, including phytohormones, for tissue and developmental stage specific responses. Unlike other phytochromes that mediate red-light responses, phyA is transported from the cytoplasm to the nucleus in far-red light by the shuttle proteins FHY1 and FHL. However, additional mechanisms must exist that shift the action of phyA to far-red light; current hypotheses are discussed.
- The Presence of Conjunctivochalasis in Obstructive Sleep Apnea Patients. [Journal Article]
- ECEye Contact Lens 2017 Jan 17
- CONCLUSIONS: The moderate and severe OSA groups were associated with higher rates and more advanced stages of CCh. We believe that detailed conjunctival assessment is necessary for patients with complaints such as burning, stinging, and foreign body sensation, which we frequently confront in daily practice. In particular, young patients diagnosed with CCh must be carefully assessed regarding sleep apnea. In light of the above findings, we suggest that patients with ocular surface symptoms that are not relieved by topical medical treatment should be assessed for CCh and OSA. Longitudinal studies monitoring the response of CCh to OSA treatment are needed to clarify the relationship between CCh and OSA.
- PERM Hypothesis: The Fundamental Machinery Able to Elucidate the Role of Xenobiotics and Hormesis in Cell Survival and Homeostasis. [Review]
- IJInt J Mol Sci 2017 Jan 15; 18(1)
- In this article the Proteasome, Endoplasmic Reticulum and Mitochondria (PERM) hypothesis is discussed. The complex machinery made by three homeostatic mechanisms involving the proteasome (P), endopla...
In this article the Proteasome, Endoplasmic Reticulum and Mitochondria (PERM) hypothesis is discussed. The complex machinery made by three homeostatic mechanisms involving the proteasome (P), endoplasmic reticulum (ER) and mitochondria (M) is addressed in order to elucidate the beneficial role of many xenobiotics, either trace metals or phytochemicals, which are spread in the human environment and in dietary habits, exerting their actions on the mechanisms underlying cell survival (apoptosis, cell cycle regulation, DNA repair and turnover, autophagy) and stress response. The "PERM hypothesis" suggests that xenobiotics can modulate this central signaling and the regulatory engine made fundamentally by the ER, mitochondria and proteasome, together with other ancillary components such as peroxisomes, by acting on the energetic balance, redox system and macromolecule turnover. In this context, reactive species and stressors are fundamentally signalling molecules that could act as negative-modulating signals if PERM-mediated control is offline, impaired or dysregulated, as occurs in metabolic syndrome, degenerative disorders, chronic inflammation and cancer. Calcium is an important oscillatory input of this regulation and, in this hypothesis, it might play a role in maintaining the correct rhythm of this PERM modulation, probably chaotic in its nature, and guiding cells to a more drastic decision, such as apoptosis. The commonest effort sustained by cells is to maintain their survival balance and the proterome has the fundamental task of supporting this mechanism. Mild stress is probably the main stimulus in this sense. Hormesis is therefore re-interpreted in the light of this hypothetical model and that experimental evidence arising from flavonoid and hormesis reasearch.
- Hydrophobic Residues near the Bilin Chromophore-Binding Pocket Modulate Spectral Tuning of Insert-Cys Subfamily Cyanobacteriochromes. [Journal Article]
- SRSci Rep 2017 Jan 17; 7:40576
- Cyanobacteriochromes (CBCRs) are a subfamily of phytochrome photoreceptors found exclusively in photosynthetic cyanobacteria. Four CBCRs containing a second Cys in the insert region (insert-Cys) have...
Cyanobacteriochromes (CBCRs) are a subfamily of phytochrome photoreceptors found exclusively in photosynthetic cyanobacteria. Four CBCRs containing a second Cys in the insert region (insert-Cys) have been identified from the nonheterocystous cyanobacterium Microcoleus B353 (Mbr3854g4 and Mbl3738g2) and the nitrogen fixing, heterocystous cyanobacterium Nostoc punctiforme (NpF2164g3 and NpR1597g2). These insert-Cys CBCRs can sense light in the near-UV to orange range, but key residues responsible for tuning their colour sensitivity have not been reported. In the present study, near-UV/Green (UG) photosensors Mbr3854g4 (UG1) and Mbl3738g2 (UG2) were chosen for further spectroscopic analysis of their spectral sensitivity and tuning. Consistent with most dual-Cys CBCRs, both UGs formed a second thioether linkage to the phycocyanobilin (PCB) chromophore via the insert-Cys. This bond is subject to breakage and relinkage during forward and reverse photoconversions. Variations in residues equivalent to Phe that are in close contact with the PCB chromophore D-ring in canonical red/green CBCRs are responsible for tuning the light absorption peaks of both dark and photoproducts. This is the first time these key residues that govern light absorption in insert-Cys family CBCRs have been identified and characterised.
- Dying at home of cancer: whose needs are being met? The experience of family carers and healthcare professionals (a multiperspective qualitative study). [Journal Article]
- BSBMJ Support Palliat Care 2017 Jan 16
- CONCLUSIONS: We have shed light on the complexity of balancing the demands and the satisfaction of caring for someone dying at home. The ability to manage these conflicting needs influenced whether carers perceived the home setting as the best place for the person to have received care in their last days of life.
- An analysis of the hospitals of Sultan Suleyman and Hurrem: Two different approaches to healthcare in sixteenth-century Ottoman Empire. [Journal Article]
- JMJ Med Biogr 2016 Jan 01; :967772016681894
- This study concentrates on two monumental Ottoman pious endowments, each with a major component devoted to healing. The first is the hospital of the Haseki Mosque Complex built by the wife of Sultan ...
This study concentrates on two monumental Ottoman pious endowments, each with a major component devoted to healing. The first is the hospital of the Haseki Mosque Complex built by the wife of Sultan Suleyman the Magnificent. An examination of the deed and the modus operandi of this endowment will impart a sense of the role that women of the ruling class played in Ottoman society as builders and healers in the sixteenth century. The analysis of the Haseki Hospital will be followed by an examination of the hospital that is part of the Suleymaniye Mosque Complex built by Sultan Suleyman. The differences between the two perspectives in the promotion of public health will be emphasized, arguing that the Sultan's approach to healthcare was academic and research-oriented, whereas his wife's was holistic and devoted to rehabilitation. The endowment deeds and the physical layouts of the two hospitals shed light upon a dual approach to healthcare with gender-specific roles affirmed and shaped by Hurrem and Suleyman the Magnificent, who each built hospitals of their own in Istanbul, the Ottoman capital city.
- Endoscopic decompression of the optic canal for traumatic optic neuropathy. [Journal Article]
- CJChin J Traumatol 2016 Dec 01; 19(6):330-332
- CONCLUSIONS: Endoscopic decompression of the optic canal is an effective way to cure TON. VEP could be used as an important reference for preoperative and prognosis evaluation. Operative time after trauma is only a relative condition that may affect the therapeutic effect of optic canal decompression. Poor results of this procedure may be related to the severity of the optic nerve injury.
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- Recent advances in light-responsive on-demand drug-delivery systems. [Journal Article]
- TDTher Deliv 2017; 8(2):89-107
- The convergence of wearable sensors and personalized medicine enhance the ability to sense and control the drug composition and dosage, as well as location and timing of administration. To date, nume...
The convergence of wearable sensors and personalized medicine enhance the ability to sense and control the drug composition and dosage, as well as location and timing of administration. To date, numerous stimuli-triggered smart drug-delivery systems have been developed to detect changes in light, pH, temperature, biomolecules, electric field, magnetic field, ultrasound and mechanical forces. This review examines the major advances within the last 5 years for the three most common light-responsive drug delivery-on-demand strategies: photochemical, photoisomerization and photothermal. Examples are highlighted to illustrate progress of each strategy in drug delivery applications, and key limitations are identified to motivate future research to advance this important field.