The cold-and menthol-sensitive receptor TRPM8 (transient receptor potential melastatin 8) has been suggested to play a role in cold allodynia, an intractable pain seen clinically. We studied how TRPM8 is involved in cold allodynia using rats with chronic constrictive nerve injury (CCI), a neuropathic pain model manifesting cold allodynia in hindlimbs. We found that cold allodynic response in the CCI animals was significantly attenuated by capsazepine, a blocker for both TRPM8 and TRPV1 (transient receptor potential vanilloid 1) receptors, but not by the selective TRPV1 antagonist I-RTX (5-iodoresiniferatoxin). In L5 dorsal root ganglion (DRG) sections of the CCI rats, immunostaining showed an increase in the percentage of TRPM8-immunoreactive neurons when compared with the sham group. Using the Ca 2ϩ -imaging technique and neurons acutely dissociated from the L5 DRGs, we found that CCI resulted in a significant increase in the percentage of menthol-and cold-sensitive neurons and also a substantial enhancement in the responsiveness of these neurons to both menthol and innocuous cold. These changes occurred in capsaicin-sensitive neurons, a subpopulation of nociceptive-like neurons. Using patch-clamp recordings, we found that membrane currents evoked by both menthol and innocuous cold were significantly enhanced in the CCI group compared with the sham group. By retrograde labeling afferent neurons that target hindlimb skin, we showed that the skin neurons expressed TRPM8 receptors, that the percentage of menthol-sensitive/cold-sensitive/capsaicin-sensitive neurons increased, and that the menthol-and cold-evoked responses were significantly enhanced in capsaicin-sensitive neurons after CCI. Together, the gain of TRPM8-mediated cold sensitivity on nociceptive afferent neurons provides a mechanism of cold allodynia.
Although
flexible and multifunctional textile-based electronics
are promising for wearable devices, it is still a challenge to seamlessly
integrate excellent conductivity into textiles without sacrificing
their intrinsic flexibility and breathability. Herein, the vertically
interconnected conductive networks are constructed based on a meshy
template of weave cotton fabrics with interwoven warp and weft yarns.
The two-dimensional early transition metal carbides/nitrides (MXenes),
with unique metallic conductivity and hydrophilic surfaces, are uniformly
and intimately attached to the preformed fabric via a spray-drying
coating approach. Through adjusting the spray-drying cycles, the degree
of conductive interconnectivity for the fabrics is precisely tuned,
thereby affording highly conductive and breathable fabrics with integrated
Joule heating, electromagnetic interference (EMI) shielding and strain
sensing performances. Interestingly, triggered by the interwoven conductive
architecture, the MXene-decorated fabrics with a low loading of 6
wt % (0.78 mg cm–2) offer an outstanding electrical
conductivity of 5 Ω sq–1. The promising electrical
conductivity further endows the fabrics with superior Joule heating
performance with a heating temperature up to 150 °C at a supply
voltage of 6 V, excellent EMI shielding performance, and highly sensitive
strain responses to human motion. Consequently, this work offers a
novel strategy for the versatile design of multifunctional textile-based
wearable devices.
A novel reduction and pH dual-sensitive nonviral vector for long-circulating and tumor-targeted siRNA delivery is described. The nanomedicine is negatively charged at neutral pH of bloodstream whereas it is positively charged at lower pH of tumor tissue (ca. 6.8). Interlayer crosslinking with disulfide bonds stabilizes the nanomedicine during blood circulation and allows quick intracellular siRNA release after endocytosis.
For a long time, oral disease is one of the major problems of the public health for its high prevalence and incidence throughout the world, which is especially true for low-income populations. Since China's economic reform in 1978, great changes have taken place in China. These changes have significant impact on and have been reflected in oral disease trends in China.This paper provides an overview and assessment of the oral health status in China. It focuses on changes in the nation's demographic profile, in the marketplace, the oral disease status and trends. The paper also suggests some possible measures and strategies for bettering oral health in future China.
Tumor-associated macrophages (TAMs)
usually display the tumor-promoting
M2 phenotype rather than the tumoricidal M1 phenotype. Thus, M2-to-M1
repolarization of TAMs has emerged as a promising strategy for tumor
immunotherapy nowadays. However, immune side effects remain a great
challenge, because phenotypic conversion of macrophages into the proinflammatory
M1 phenotype may also be induced in normal tissue. Here, aiming at
repolarizing TAMs without altering the M1/M2 polarization balance
in healthy organs, we develop a micellar nanodrug with M2-targeting
peptides (M2peptide) hidden in the pH-sheddable PEG corona so that
an active targeting of M2-like macrophages is triggered only in the
acidic tumor microenvironment (TME). The smart nanodrug effectively
functions M2-to-M1 repolarization via M2-targeted codelivery of IKKβ
siRNA and STAT6 inhibitor AS1517499 (AS), which suppresses the tumor
growth and metastasis. Moreover, immune side effects are reduced because
the neutral-pH environment in healthy organs does not trigger a “stealth-to-nonstealth”
conversion of the nanodrug essential for M2-targeted drug delivery.
The spectroscopic and photophysical properties of three gold( 1)-acetylide complexes [N (PPh,),] -[Au(CzCPh),], [Au(PPh,)(C-CPh)] and [{Au(C-CPh)},(p-dppe)] [dppe = 1,2-bis(diphenyIphosphino)ethane] are described. X-Ray crystal analysis of the latter showed a weak metal-metal interaction in the solid state with the shortest Au -Au separation being 3.1 53(2) A. The gold(1)acetylide complexes have long-lived and emissive ,(n,n*) excited states in solutions at room temperature. The photoreaction of [Au( PPh,) (C-CPh)] with methyl viologen has been investigated by Stern-Volmer quenching and flash-photolysis experiments.
The cold- and menthol-sensing TRPM8 receptor has been proposed to have both nonnociceptive and nociceptive functions. However, one puzzle is how this single type of receptor may be used by somatosensory neurons to code for two distinct sensory modalities. Using acutely dissociated rat dorsal root ganglion (DRG) neurons without culture, we show that TRPM8 receptors are expressed on two distinct classes of somatosensory neurons. One class is sensitive to menthol and features nonnociceptive neuron properties, including capsaicin-insensitive, ATP-insensitive, transient acid response, and expression of TTX-sensitive sodium channels only. This class is termed the menthol-sensitive/capsaicin-insensitive neuron class (MS/CIS). The other class is also sensitive to menthol but has characteristics of nociceptive neurons including capsaicin-sensitive, ATP-sensitive, prolonged acid response, and expression of both TTX-sensitive and TTX-resistant sodium channels. This class is termed the menthol-sensitive/capsaicin-sensitive neuron class (MS/CS). The presence of these two neuron classes in acutely dissociated DRG neurons support the idea that TRPM8 receptors can have both nonnociceptive and nociceptive functions. While both neuron classes respond to menthol and cold, the overall responses induced by menthol and cold are significantly larger in MS/CIS than in MS/CS neurons. Furthermore, low concentrations of menthol produce strong selection of the MS/CIS neuron population over the MS/CS neuron population. On the other hand, the population selection becomes weaker with higher concentrations of menthol. TRPM8 current density shows significant higher in MS/CIS neurons than in MS/CS neurons, suggesting different expression levels of TRPM8 receptors between the two neuron populations, and this difference may provide a mean of selective activation of MS/CIS neurons at low stimulation intensity.
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