OBJECTIVE: To investigate the preparation and properties of the novel silica (SiO ₂)/hydroxyapatite (HAP) whiskers porous ceramics scaffold. METHODS: The HAP whiskers were modified by the SiO ₂ microspheres using the Stöber method. Three types of SiO ₂/HAP whiskers were fabricated under different factors (for the No.1 samples, the content of tetraethoxysilane, stirring time, calcination temperature, and soaking time were 10 mL, 12 hours, 560℃, and 0.5 hours, respectively; and in the No.2 samples, those were 15 mL, 24 hours, 650℃, and 2 hours, respectively; while those in the No.3 samples were 20 mL, 48 hours, 750℃, and 4 hours, respectively). The phase and morphology of the self-made HAP whisker and 3 types of SiO ₂/HAP whiskers were detected by the X-ray diffraction analysis and scanning electron microscopy. Taken the self-made HAP whisker and 3 types of SiO ₂/HAP whiskers as raw materials, various porous ceramic materials were prepared using the mechanical foaming method combined with extrusion molding method, and the low-temperature heat treatment. The pore structure of porous ceramics was observed by scanning electron microscopy. Its porosity and pore size distribution were measured. And further the axial compressive strength was measured, and the biodegradability was detected by simulated body fluid. Cell counting kit 8 method was used to conduct cytotoxicity experiments on the extract of porous ceramics. RESULTS: The SiO ₂ microspheres modified HAP whiskers and its porous ceramic materials were prepared successfully, respectively. In the SiO ₂/HAP whiskers, the amorphous SiO ₂ microspheres with a diameter of 200 nm, uniform distribution and good adhesion were attached to the surface of the whiskers, and the number of microspheres was controllable. The apparent porosity of the porous ceramic scaffold was about 78%, and its pore structure was composed of neatly arranged longitudinal through-holes and a large number of micro/nano through-holes. Compared with HAP whisker porous ceramic, the axial compressive strength of the SiO ₂/HAP whisker porous ceramics could reach 1.0 MPa, which increased the strength by nearly 4 times. Among them, the axial compressive strength of the No.2 SiO ₂/HAP whisker porous ceramic was the highest. The SiO ₂ microspheres attached to the surface of the whiskers could provide sites for the deposition of apatite. With the content of SiO ₂ microspheres increased, the deposition rate of apatite accelerated. The cytotoxicity level of the prepared porous ceramics ranged from 0 to 1, without cytotoxicity. CONCLUSION SiO ₂/HAP whisker porous ceramics have good biological activity, high porosity, three-dimensional complex pore structure, good axial compressive strength, and no cytotoxicity, which make it a promising scaffold material for bone tissue engineering.
Animals ; Durapatite ; Porosity ; Vibrissae ; Apatites ; Ceramics ; Silicon Dioxide

OBJECTIVE: To systematically evaluate the repairing effect of stem cells on facial nerve defects. METHODS: Articles regarding the regenerating effect of stem cells on facial nerves in animals were collected from the databases of Pubmed, Cochrane Library, Web of Science, Embase, Scopus, and CBM. Two professionals independently completed the article screening, data extraction, and bias risk assessment. RevMan 5.3 and random-effects models were used for the statistical analysis, and the results were presented in the form of mean differences (MD) with a 95%CI. The results of functional evaluation (vibrissae movement, facial paralysis) and histological evaluation (density of myelinated fibers, diameter of fibers, thickness of myelin sheath, G ratio) of facial nerve were Meta-analyzed. RESULTS: A total of 4 614 articles were retrieved from the 6 databases, and 15 of these articles were included in the Meta-analysis. For vibrissae movement and facial paralysis, the stem cell group scored significantly higher than the non-stem cell group (P<0.05). The density of myelinated fibers and thickness of the myelin sheath in the stem cell group were higher than those in the non-stem cell group (P<0.05). The G ratio in the stem cell group was smaller than that in the non-stem cell group (P=0.001). There was no significant difference in fiber diameter (P=0.08). CONCLUSIONS Stem cells have potential in promoting facial nerve regeneration.
Animals ; Facial Nerve ; Facial Paralysis ; Nerve Regeneration ; Stem Cells ; Vibrissae

Animals ; Hair ; transplantation ; Humans ; Skin Transplantation ; Vibrissae

Adenylyl cyclase type-5 (AC5) is preferentially expressed in the dorsal striatum. Recently, we reported that AC5 knockout (KO) mice preferred food pellets carrying an olfactory cue produced by AC5 KO mice during food consumption (AC5 KO pellets) over food pellets that had been taken by wildtype (WT) mice. In the present study, we demonstrated that whisker trimming on the right side of the face but not the left in AC5 KO mice blocked the behavioral preference for AC5 KO pellets. Conversely, whisker trimming on the right but not the left in WT mice induced a behavioral preference for AC5 KO pellets. Mice lacking D2 dopamine receptor (D2 KO mice) also showed a behavioral preference for AC5 KO pellets. In D2 mice, whisker trimming on the right side of the face but not the left blocked a behavioral preference for AC5 KO food pellets. AC5 KO mice had increased level of phospho-CaMKIIα in the dorsal striatum, and WT mice with whiskers cut on either side also showed increased p-CaMKIIα level in the dorsal striatum. The siRNA-mediated inhibition of CaMKIIα in the dorsal striatum in either the right or the left hemisphere in AC5 KO mice and D2 KO mice blocked the behavioral preference for AC5 KO pellets. However, behavioral changes induced by this inhibition on each side showed asymmetrical time courses. These results suggest that an unconditioned behavioral preference for specific food pellets can be switched on or off based on the balance of states of neural activity in the dorsal striatum regulated by a signaling pathway centered on AC5 and D2 and the sensory inputs of whiskers from the right side of the face.
Animals ; Cues ; Mice ; Receptors, Dopamine ; Vibrissae* ; Adenylyl Cyclases

Adenylyl cyclase type-5 (AC5) is preferentially expressed in the dorsal striatum. Recently, we reported that AC5 knockout (KO) mice preferred food pellets carrying an olfactory cue produced by AC5 KO mice during food consumption (AC5 KO pellets) over food pellets that had been taken by wildtype (WT) mice. In the present study, we demonstrated that whisker trimming on the right side of the face but not the left in AC5 KO mice blocked the behavioral preference for AC5 KO pellets. Conversely, whisker trimming on the right but not the left in WT mice induced a behavioral preference for AC5 KO pellets. Mice lacking D2 dopamine receptor (D2 KO mice) also showed a behavioral preference for AC5 KO pellets. In D2 mice, whisker trimming on the right side of the face but not the left blocked a behavioral preference for AC5 KO food pellets. AC5 KO mice had increased level of phospho-CaMKIIα in the dorsal striatum, and WT mice with whiskers cut on either side also showed increased p-CaMKIIα level in the dorsal striatum. The siRNA-mediated inhibition of CaMKIIα in the dorsal striatum in either the right or the left hemisphere in AC5 KO mice and D2 KO mice blocked the behavioral preference for AC5 KO pellets. However, behavioral changes induced by this inhibition on each side showed asymmetrical time courses. These results suggest that an unconditioned behavioral preference for specific food pellets can be switched on or off based on the balance of states of neural activity in the dorsal striatum regulated by a signaling pathway centered on AC5 and D2 and the sensory inputs of whiskers from the right side of the face.
Animals ; Cues ; Mice ; Receptors, Dopamine ; Vibrissae* ; Adenylyl Cyclases

Synaptic plasticity of barrel cortex is one of the most widely studied topics in neuroscience in recent years. The primary somatosensory cortex of the rodent has a good topology character,which provides an ideal experimental model for plasticity study. This system displays very strong experience-dependent plasticity both during development and in adulthood. The changes of sensory cortex's neural circuit can induce experience-dependent plasticity. In the synaptic level,thalamocortical synapse is considered to be the main location of plasticity. In the circuit level,both synapses from layer 4 to layer 2/3 and those within layer 2/3 are also the necessary parts of achieving synaptic plasticity in primary somatosensory cortex. The GABAergic inhibitory circuit may be involved in this plasticity of S1, but the exact mechanism remains unknown.
Animals ; Neural Pathways ; physiology ; Neuronal Plasticity ; Somatosensory Cortex ; physiology ; Synapses ; physiology ; Thalamus ; physiology ; Vibrissae ; physiology

OBJECTIVETo research the effects of incorporating tetrapod-like zinc oxide whisker (T-ZnOw) of different proportions on the antibacterial activity of different kinds of soft denture liners.

METHODSThe minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of T-ZnOw against Saccharomyces albicans (S. albicans) were examined by the broth dilution test. Add T-ZnOw 0%, 1%, 2%, 3% to Silagum soft denture liners and soft denture liners respectively. The antimicrobial rate of S. albicans was determined by the membrane covering method.

RESULTSThe MIC of T-ZnOw against S. albicans was 78 microg mL(-1) and the MBC was 156 microg mL(-1). Comparing 1%, 2%, 3% T-ZnOw group with control group, the results showed significant difference (P<0.05). And as the T-ZnOw antibacterial agent added ratio increased, antibacterial increased significantly.

CONCLUSIONThe soft denture liners incorporating with 1%, 2%, 3% of T-ZnOw can improve antibacterial activity. Following the increased proportions of T-ZnOw, antibacterial rate was significantly increasing.

Animals ; Anti-Bacterial Agents ; Denture Liners ; Microbial Sensitivity Tests ; Vibrissae ; Zinc Oxide

OBJECTIVETo discuss the influence of nano-silica content which was hydrolyzed by tetraethyl orthosioate (TEOS) on the aluminum borate whisker (AlBw) and silica filler composite resins on flexural properties.

METHODSThe nanometer-size silicon dioxide (SiO2) particles were prepared by sol-gel method based on tetraethyl orthosioate. Different proportion of AlBw and SiO2 were fused and attached onto the surface of AlBw through high temperature, then polymerized with resin matrix after surface siliconization and their flexural strength and flexural modulus were determined. The effects of heat treatment to the surface morphology of AlBw and the shapes of the mixture at various proportions were characterized by TEM.

RESULTSThe flexural properties of dental composite resins with AlBw-SiO2 compound as inorganic fillers were significantly improved. The flexural property of a new type of dental composite resins was(130.29 +/- 8.38) MPa, when the mass ratio of AlBw and nano-SiO2 particle was 3:1.

CONCLUSIONNano-silica content which was hydrolyzed by tetraethyl orthosioate improved flexural properties of the aluminum borate whisker and silica filler composite resins.

Acrylic Resins ; Aluminum ; Animals ; Borates ; Composite Resins ; Materials Testing ; Pliability ; Polyurethanes ; Silanes ; Silicon Dioxide ; Vibrissae

OBJECTIVETo investigate the change of behavior, as well as the plasticity of somatosensory cortex after whisker trimming.

METHODSSD rats were divided into 4 groups. Group A is the normal control group; group B: bilateral vibrissotomy on the second postnatal day; group C: unilateral right vibrissotomy on the second postnatal day; group D: right unilateral whisker trimmed during 1-5 days after birth, and leave untreated after the 5th postnatal day. Their body weight, length of the left D2 whiskers was measured on the 30th postnatal day. At the same time, the changes of their behavior (including the slit-detection test, the home exploring behavior and thigmotaxis test) were also recorded on the 30th postnatal day. Cytochrome oxydase histochemistry (CO reaction)was applied to study the development and arrangement of barrel cortex.

RESULTSIn the slit-detection test, control rats could find and get into the right slit very quickly. The rats in group B could get into the slit only if their noses touched the slit. The rats in group C couldn't identify the slit by right face, but if they turned their body and touched the slit with the left whiskers, they could get into the slit very quickly. The behavior of rats in group D was similar to that in group C. The time spent for finding out the right slit of the rats in group A, B, C was obviously longer than that of group A (P < 0.01, P < 0.05, P < 0.01). In the exploring behavior and thigmotaxis test, the time for left thigmotaxis, right thigmotaxis and total thigmotaxis of rats in group B was longer than that of control animals. The time for right thigmotaxis of group C was significantly shorter than that of group A (P < 0.05). Both the weight of the rats and the length of left D2 whiskers of rats in all the four groups had no significant difference. CO reaction showed that the barrels became smaller, the septum was not clear, the arrangement of the barrels was not tidy in the mice whose right whiskers were trimmed from 2-30 days after birth.

CONCLUSIONDeafferentation doesn't change the body weight and length of the whiskers left. But the stimulation of whiskers is important for rodent especially in thigmotaxis and exploring behavior. Deafferentation can also induce the plastic change of barrel cortex.

Animals ; Animals, Newborn ; Cerebral Cortex ; physiology ; Male ; Neuronal Plasticity ; Physical Stimulation ; Rats ; Rats, Sprague-Dawley ; Somatosensory Cortex ; physiology ; Vibrissae

The purpose of this study was to establish a model of trigeminal neuralgia (TN) through an approach from lower edge of cheekbone and to observe the functional changes in the voltage-gated potassium currents in the cultured trigeminal ganglion (TG) neurons. Thirty Sprague-Dawley male rats were divided into two groups, the sham-operated (sham) group and the operated group. The TN model was carried out by using a chronic constriction injury of the infraorbital nerve (ION-CCI) from lower edge of cheekbone. Peripheral pain threshold test and whole-cell patch clamp recording were used to determine the difference between sham and ION-CCI rats. The withdrawal threshold of whisker pad in operated side of ION-CCI rat was decreased significantly from 6 d after operation and then maintained until 21 d, with the lowest on the 15th day. The threshold of whisker pad in non-operated side of operated rats was also decreased significantly compared with that in the sham group. Delayed rectifier potassium current (I(K)) in cultured ION-CCI TG neurons was decreased significantly compared with that in the sham group. Transient outward potassium currents (I(A)) in both operated and non-operated sides of TG neurons from ION-CCI rats were also reduced significantly compared with that in the sham group. The present study provided a new method of ION-CCI. In this model, the decrease of I(A) and I(K) might contribute, at least in part, to the decrease in mechanical pain threshold of whisker pad and the subsequent hyperalgia.
Animals ; Cells, Cultured ; Constriction ; Disease Models, Animal ; Hyperalgesia ; Male ; Pain Threshold ; Patch-Clamp Techniques ; Potassium Channels ; metabolism ; Rats ; Rats, Sprague-Dawley ; Trigeminal Ganglion ; metabolism ; Trigeminal Neuralgia ; physiopathology ; Vibrissae