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1.
Opt Lett ; 49(11): 3194-3197, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824361

RESUMO

Here, we demonstrate the realization of hollow-core light cages (LCs) on commercial step-index fibers using 3D nanoprinting, resulting in fully fiber-integrated devices. Two different light cage geometries with record-high aspect ratio strands and unique sidewise access to the core have been implemented, exhibiting excellent optical and mechanical properties. These achievements are based on the use of 3D nanoprinting to fabricate light cages and stabilize them with customized support elements. Overall, this approach results in novel, to the best of our knowledge, fiber-interfaced hollow-core devices that combine several advantages in a lab-on-a-fiber platform that is particularly useful for diffusion-related applications in environmental sciences, nanosciences, and quantum technologies.

2.
Opt Lett ; 48(20): 5411-5414, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37831880

RESUMO

Here, we demonstrate the properties of bromotrichloromethane (CBrCl3) in the context of ultrafast supercontinuum generation in liquid-core fibers. Broadband interferometric and spectroscopic measurements of liquids and fibers indicate suitable optical properties of this halomethane for near-IR supercontinuum generation, which were confirmed in corresponding experiments using ultrashort pulses. The associated simulations showed consistent broadband power redistributions, thus confirming that this halomethane is a suitable candidate for ultrafast nonlinear frequency conversion in liquid-core fibers. It uniquely combines the advantages of an inorganic, i.e., CH-free, material with a non-vanishing hyperpolarizability, allowing to anticipate an integration of second-order nonlinearity into the fiber.

3.
Environ Microbiol ; 23(11): 6557-6568, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34490978

RESUMO

Solid diet supplementation in the early life stages of ruminants could improve rumen microbiota and tissue development. However, most studies focus on bacteria in the rumen content community. The microbiota attached on rumen epithelium are rarely investigated, and their correlations with rumen content bacteria and host transcripts are unknown. In this study, rumen digesta attached in the epithelium from goats in three diet regimes (milk replacer only, milk replacer supplemented concentrate and milk replacer supplemented concentrate plus alfalfa pellets) were collected for measurement of the epithelial microbiota using next generation sequencing. Correspondingly, the rumen tissues of the same animals were measured with the host transcriptome. The distinct microbial structures and compositions between rumen content and epithelial communities were associated with solid diet supplementation. Regarding rumen development in pre-weaning ruminants, a solid diet, especially its accompanying neutral detergent fibre nutrients, was the most significant driver that influenced the rumen microbiota and epithelium gene expression. Compared with content bacteria, rumen epithelial microbiota had a stronger association with the host transcriptome. The host transcriptome correlated with host phenotypes were associated with rumen epithelial microbiota and solid diet. This study reveals that the epithelial microbiota is crucial for proper rumen development, and solid diet could improve rumen development through both the rumen content and epithelial microbiota.


Assuntos
Microbiota , Rúmen , Ração Animal/análise , Animais , Dieta/veterinária , Microbiota/genética , Rúmen/microbiologia , Ruminantes/genética , Transcriptoma
4.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(2): 216-21, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-27079000

RESUMO

OBJECTIVE: To explore possible mechanism of electroacupuncture (EA) for regulating immune function in anxiety disorder (AD) rats by observing the effect of acupuncture on the histology of thymus and expressions of atrial natriuretic peptide (ANP) and natriuretic peptide receptor type A (NPR- A) in thymus. METHODS: Totally 34 SD healthy rats were randomly divided into the blank control group (n = 10), the model group (n = 12), the EA group (n = 12). Anxiety model was established in rats of the model group and the EA group by using chronic unpredictable stress (CUS) stimulation. EA (15/25 Hz) at Neiguan (PC6) and Shenmen (HT7) was performed in the EA group, with 15-min needle retaining, once every other day, 15 days in total. Needle was fixed at same acupoints for 15 min without electric stimulus in the other two groups. Anxiety-like behavior was measured by elevated plus-maze (EPM) test. Pathological changes of thymus tissue were observed by optical microscope. Expressions of ANP and NPR-A in thymus were measured by immunohistochemical assay. RESULTS: The thymus tissue in the model group was severely atrophied, with unclear structure of thymic lobules, unclear margin of thymic medulla, loosely arranged lymphocytes ,and obviously enlarged volume of thymic corpuscle. The thymus tissue in the EA group was mildly atrophied, with existent structure of thymic lobules, clear margin of thymic medulla, densely arranged lymphocytes in cortical region, and widened medullary area. Com- pared with the blank control group, the percentage of open-arms entries (OE%) in the total QE times ob- viously decreased in the model group (P < 0.05), ANP expression obviously increased (P < 0.05), and NPR-A expression obviously decreased (P < 0.01). Compared with the model group, OE% was obviously elevated (P < 0.05), ANP expression obviously decreased (P < 0.05), and NPR-A expression obviously increased (P < 0.01) in the EA group. CONCLUSION: EA not only could reduce anxiety of rats, but also could improve chronic stress induced thymus injury through intervening synthesis and secretion of ANP, as well as the expression of NPR-A (a specific receptor of ANP).


Assuntos
Transtornos de Ansiedade/terapia , Fator Natriurético Atrial/metabolismo , Eletroacupuntura , Receptores do Fator Natriurético Atrial/metabolismo , Timo/patologia , Pontos de Acupuntura , Animais , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
5.
Front Bioeng Biotechnol ; 11: 1330082, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38173868

RESUMO

Background: Knee osteoarthritis (KOA) is a common degenerative disease among the older people that severely affects their daily life. Previous studies have confirmed that movement biomechanics are altered in patients with KOA during task performance. However, changes that occur in lower limb joints and muscles in the three planes during stand-to-sit (STS) tasks in patients with early-stage KOA are unclear. Method: Of the 36 participants recruited in this study, 24 (8 males and 16 females) and 12 (4 males and 8 females) were added to the KOA and control groups, respectively. The Nexus Vicon motion capture system along with Delsys wireless surface electromyography devices and plantar pressure measurement mat was used to record test data. A Visual 3D software was used to process the data and calculate the biomechanical and electromyographic parameters during STS tasks. Results: There was no significant difference in task duration between the two groups. Patients with KOA could perform a greater range of pelvic motion and smaller range of hip and knee joint motion with a lower maximum hip joint angular acceleration in the sagittal plane and greater knee and ankle joint motion in the coronal plane. There was no significant difference in the motion range in the horizontal plane. During the STS task, patients in the KOA group had a lower vertical ground reaction force (GRF) amplitude on the injured side but a higher integrated GRF on both sides than those in the control group. Moreover, patients with KOA demonstrated higher PERM and PABM of the lower limb joints and smaller knee PADM and ankle PEM. Additionally, maximum activation levels of GMed muscle, affected-side gluteus medius (GM), ST, rectus femoris (RF), and tibialis anterior (TA) muscles were lower in patients with KOA than in controls. Conversely, the activation level of biceps femoris (BF) was higher. Furthermore, the integral EMG values of GMed, GM, ST, VL, RF, vastus medialis VM, and TA muscles on the affected side were lower, except for the BF muscle, in patients with KOA. Conclusion: Compared with the participants in the control group, patients with early-stage KOA exhibited consistent changes in sEMG parameters and biomechanical alterations in the sagittal plane, as observed in previous studies. However, differences in parameters were observed in the coronal and transverse planes of these patients. The noninvasive analysis of the 3D parameters of the involved motion patterns may lead to the early detection of KOA.

6.
J Anim Sci ; 98(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32249903

RESUMO

Neutral detergent fiber (NDF), as the main component of structural carbohydrate in forage, is a vital factor impacting the performance of young ruminants. The objective of this study was to evaluate the effect of starter NDF level on the rumen fermentation and morphometrics of lambs fed isocaloric and isonitrogenous diets. One hundred Hu sheep lambs (18 days of age and 6.1 ± 0.1 kg body weight [BW]) were randomly assigned to one of the four starter diets differing in their NDF levels on a dry matter (DM) basis: 1) diet with 14% NDF (NDF14), 2) diet with 18% NDF (NDF18), 3) diet with 22% NDF (NDF22), and 4) diet with 26% NDF (NDF26). Lambs were fed milk replacer with designed starters from 21 to 60 d of age and then transitioned to the same starter feed until 90 d of age. Six lambs from each treatment (close to the average BW of the corresponding treatment) were selected and slaughtered at 90 d of age for measuring rumen fermentation, anatomical development, and morphometric characteristics. Lambs receiving NDF22 and NDF26 starter diets had greater (P < 0.05) intake of starter and total DM, and average daily gain during the overall period, thereby heavier (P < 0.05) final weights at 90 d of age compared with those fed NDF14 starter diet. At 90 d of age, lambs fed NDF22 and NDF26 starters had higher rumen pH, followed by lower propionate, higher acetate concentrations (P < 0.05), and a higher acetate-to-propionate ratio compared with those fed NDF14 and NDF18 starters (P < 0.05). No significant differences of the full and empty weight of reticulorumen were observed among treatments; however, the reticulorumen weight expressed as a percentage of the complex stomach weight was lower (P < 0.05) in lambs fed NDF22 and NDF26 starters compared with those fed NDF14 starter. Furthermore, NDF14 lambs had the thickest keratin layer and epithelium compared with those in the other treatments but showed the thinnest muscle layer (P < 0.05). These results suggest that increasing starter NDF levels can ameliorate the rumen fermentation environment and alleviate hyperkeratosis and plaque formation in the rumen epithelium. In summary, including 22% and 26% NDF in the pelleted starter can improve the performance of lambs.


Assuntos
Ração Animal/análise , Dieta/veterinária , Fibras na Dieta/administração & dosagem , Rúmen/crescimento & desenvolvimento , Ovinos/crescimento & desenvolvimento , Animais , Fibras na Dieta/metabolismo , Ingestão de Energia , Rúmen/metabolismo , Ovinos/fisiologia
7.
Microorganisms ; 8(8)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722119

RESUMO

Early microbial colonization in the gut impacts animal performance and lifelong health. However, research on gut microbial colonization and development in young ruminants, especially after weaning, is currently limited. In this study, next-generation sequencing technology was performed to investigate the temporal dynamic changes of the microbial community in the jejunum and colon of goats at 1, 7, 14, 28, 42, 56, 70, and 84 days (d) of age. As age increased, significant increases in microbial diversity, including the number of Observed OTUs and the Shannon Index, were observed in both the jejunum and colon. Regarding beta diversity, significant shifts in community membership and structure from d1 to d84 were observed based on both Bray-Curtis and Jaccard distances. With increasing age, dominant genera in the jejunum shifted from Lactobacillus to unclassified Ruminococcaceae, unclassified Lachnospiraceae and unclassified Clostridiales through starter supplementation, whereas colonic dominant genera changed from Lactobacillus and Butyricicoccus, within d1-d28, to unclassified Ruminococcaceae, unclassified Clostridiales and Campylobacter after solid diet supplementation. The linear discriminant analysis (LDA) effect size (LEfSe) analysis revealed bacterial features that are stage-specific in the jejunum and colon, respectively. In the jejunum and colon, a significantly distinct structure and membership of the microbiota was observed across all ages. The growth stage-associated microbiota in each gut compartment was also identified as a marker for biogeography. Our data indicate the temporal and spatial differences of the gut microbiota in goats are important for their performance and health. Early microbial colonization can influence microbial composition in later life (e.g., post-weaning phase). This study provides insights that the temporal dynamics of gut microbiota development from newborn to post-weaning can aid in developing feeding strategies to improve goat health and production.

8.
Microorganisms ; 7(11)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683646

RESUMO

The feeding regime of early, supplementary solid diet improved rumen development and production in goat kids. However, the signature microbiota responsible for linking dietary regimes to rumen function shifts are still unclear. This work analyzed the rumen microbiome and functions affected by an early solid diet regime using a combination of machine learning algorithms. Volatile fatty acids (i.e., acetate, propionate and butyrate) fermented by microbes were found to increase significantly in the supplementary solid diet groups. Predominant genera were found to alter significantly from unclassified Sphingobacteriaceae (non-supplementary group) to Prevotella (supplementary solid diet groups). Random Forest classification model revealed signature microbiota for solid diet that positively correlated with macronutrient intake, and linearly increased with volatile fatty acid production. Bacteria associated with carbohydrate and protein metabolism were also identified. Utilization of a Fish Taco analysis portrayed a set of intersecting core species contributed to rumen function shifts by the solid diet regime. The core community structures consisted of the specific, signature microbiota and the manipulation of their symbiotic partners are manipulated by extra nutrients from concentrate and/or forage, and then produce more volatile fatty acids to promote rumen development and functions eventually host development. Our study provides mechanisms of the microbiome governed by a solid diet regime early in life, and highlights the signature microbiota involved in animal health and production.

9.
Otol Neurotol ; 40(9): 1246-1252, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31469797

RESUMO

HYPOTHESIS: The characteristics of auditory brainstem response (ABR), electrocochleogram (ECochG), and distortion product otoacoustic emissions (DPOAE) of different degrees of selective outer hair cells (OHCs) loss may be helpful for clinicians to evaluate the pathogeny, diagnosis, and rehabilitation of individuals' hearing loss. BACKGROUND: How many OHCs are necessary to maintain cochlear amplifier function remains unknown. The electrophysiologic characteristics may indicate different degrees of OHCs loss. METHODS: Electrophysiological characteristics were tested using 8-kHz pure-tone stimulus and OHCs counted specifically in the region of the cochlea corresponding to 8-kHz. Rat models of selective OHCs loss were established by injecting kanamycin (KM) at various dosages, and the region of 8-kHz was obtained by 8-kHz pure-tone exposure. RESULTS: The ABR thresholds were affected slightly with OHCs loss < 30%, and were increased dramatically with OHCs loss ranging from 30 to 70%, but the thresholds did not increase further when OHCs loss exceeded 70%. As OHCs loss increased, the compound action potential (CAP) amplitude decreased. The CAP amplitude and OHCs loss were negatively correlated. Moreover, the summating potential (SP)/action potential (AP) increased as OHCs loss increased. DPOAE and cochlear microphonics (CM) exhibited reduced amplitudes when OHCs loss < 30%. CONCLUSIONS: Electrophysiologic characteristics may indicate different degrees of OHCs loss. While OHCs loss > 70%, the cochlear amplification may lose completely, but it is difficult to detect OHCs loss < 30%, because the ABR or DPOAE may reveal "normal" at this level. Moreover, the decreased CAP amplitude or increased SP/AP may be indicators for OHCs loss.


Assuntos
Células Ciliadas Auditivas Externas/patologia , Perda Auditiva Neurossensorial/patologia , Perda Auditiva Neurossensorial/fisiopatologia , Emissões Otoacústicas Espontâneas/fisiologia , Animais , Audiometria de Resposta Evocada , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley
10.
Zhongguo Zhen Jiu ; 35(1): 101-4, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25906584

RESUMO

Anxiety disorder is one of the most common mental disorders and seriously impairs the physical and mental health of patients. Due to the efficacy of acupuncture for tranquilization, acupuncture displays its unique advantage on the treatment of anxiety disorder, but the relevant biological mechanism has not been elaborated. The modern medicine study has proved that the heart and brain have their own independent natriuretic peptide (NP) system. The dysfunction of ANP and its receptor are closely related to the occurrence of anxiety disorder. The ANP acts on anti-anxiety. Hence, focusing on the three aspects, named the anti-anxiety effect of acupuncture based on its tranquilizing effect, the anti-anxiety effect of ANP and the positive regulation of acupuncture on NP, the mechanism on ANP and its receptor was explored in anti-anxiety with acupuncture based on tranquilizing effect, and the idea was put forward on that the anti-anxiety effect of acupuncture was possibly based on its action of tranquilization through regulating the ANP and its receptor. As a result, it is expected to provide the theoretic support for the mechanism study on anti-anxiety with acupuncture based on its tranquilizing effect.


Assuntos
Terapia por Acupuntura , Ansiolíticos/metabolismo , Ansiedade/metabolismo , Ansiedade/terapia , Fator Natriurético Atrial/metabolismo , Receptores do Fator Natriurético Atrial/metabolismo , Animais , Humanos
11.
Zhen Ci Yan Jiu ; 40(4): 265-9, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26502538

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) intervention on the levels of CD 4+ and CD 8+ lymphocytes in the plasma and thymus in anxiety disorder rats, so as to explore its mechanism underlying favorable regulation of immune function. METHODS: Thirty-four SD rats were randomly divided into control (n = 10) , model (n = 12) and EA (n = 12) groups. The anxiety model was established by using chronic unpredictable emotional stress stimulation (fasting, water-deprivation, shaking, tail-clamping, forced warm- and cool-water swimming, electrical shock stimulation, etc.) for 15 days. EA (15 Hz/ 25 Hz) was applied to "Neiguan" (PC 6) and "Shenmen" (HT 7) for 15 min, once every other day for 15 days. The anxiety-like behavior was measured by elevated plus maze test. Anxiety reduction in the plus-maze is indicated by an increase in the proportion of time spent in the open arms (time in open arms/total time in open or closed arms) , and an increase in the proportion of entries into the open arms (entries into open arms/total entries into open or closed arms). While the contents and expression of CD 4+ and CD 8+ in the plasma and thymus tissues were measured by ELISA and immunohistochemistry, respectively. RESULTS: The values of proportions of open-arm entries (OE%) and the content of plasma CD 4+ lymphocytes were obviously lower in the model group than in the control group (P < 0.05), and were significantly higher in the EA group than in the model group (P < 0.05). Whereas, the content of plasma CD 8+ lymphocytes was obviously higher in the model group than in the control group (P < 0.05) and markedly down-regulated in the EA group after the treatment (P < 0.05). The ratio of CD 4+/CD 8+ was decreased in the model group in comparison with the control group (P = 0.054), and was significantly up-regulated in the EA group after EA stimulation (P < 0.01). Compared with the control group, the expression levels (optical density, OD values) of CD 4+ and CD 8+ lymphocytes in the thymus tissue were obviously decreased in the model group (P < 0.01). After EA, the expression levels of thymus CD 4+ and CD 8+ were remarkably up-regulated in the EA group (P < 0.05). No significant changes were found in proportion of open-arm time (OT%, P > 0.05). CONCLUSION: EA can effectively relieve anxiety disorder in anxiety rats, which may be related to its effects in up-regulating plasma CD 4+ , thymus CD 4+ and CD 8' levels as well as CD 4+/CD 8+ ratio, and down-regulating plasma CD 8+ content.


Assuntos
Ansiedade/terapia , Eletroacupuntura , Subpopulações de Linfócitos T/imunologia , Timo/imunologia , Animais , Ansiedade/imunologia , Ansiedade/psicologia , Contagem de Linfócito CD4 , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Estresse Psicológico
12.
Zhonghua Fu Chan Ke Za Zhi ; 38(4): 213-5, 2003 Apr.
Artigo em Zh | MEDLINE | ID: mdl-12885367

RESUMO

OBJECTIVE: To investigate the physiologic course of third stage of labor, and to judge the optimal time of natural placental separation permitted. METHODS: To observe and record the course of third stage of labor by continuous dynamic ultrasonography and to estimate the total amount of blood loss from placental separation within two hours after delivery by the method of weighing lost blood. RESULTS: Third stage of labor can be divided into four phases: the latent phase (4.37 +/- 3.78) min, the contraction phase (1.48 +/- 0.97) min, the detachment phase (0.50 +/- 0.00) min, and the expulsion phase (0.62 +/- 2.23) min. In 85% of the puerperas the third stage of labor takes about 10 minutes (average 6.94 minutes). The amount of postpartum hemorrhage and the risk of the patient increased prominently if the time of stage of labor was longer than 10 minutes (P < 0.01). CONCLUSION: The third stage of labor must be limited in 10 minutes to prevent postpartum hemorrhage.


Assuntos
Terceira Fase do Trabalho de Parto/fisiologia , Placenta/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Ultrassonografia Pré-Natal , Adulto , Parto Obstétrico/métodos , Feminino , Humanos , Placenta/fisiologia , Hemorragia Pós-Parto/prevenção & controle , Gravidez , Fatores de Tempo , Útero/diagnóstico por imagem , Útero/fisiologia
13.
Biomed Res Int ; 2014: 647068, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24977156

RESUMO

Rosin, an abundant raw material from pine trees, was used as a starting material directly for the synthesis of rosin acid starch. The esterification reaction was catalyzed by lipase (Novozym 435) under mild conditions. Based on single factor experimentation, the optimal esterification conditions were obtained as follows: rosin acid/anhydrous glucose unit in the molar ratio 2:1, reaction time 4 h at 45°C, and 15% of lipase dosage. The degree of substitution (DS) reaches 0.098. Product from esterification of cassava starch with rosin acid was confirmed by FTIR spectroscopy and iodine coloration analysis. Scanning electron microscopy and X-ray diffraction analysis showed that the morphology and crystallinity of the cassava starch were largely destroyed. Thermogravimetric analysis indicated that thermal stability of rosin acid starch decreased compared with native starch.


Assuntos
Lipase/química , Resinas Vegetais/química , Amido/síntese química , Ácidos , Catálise , Ativação Enzimática , Esterificação , Teste de Materiais , Energia Renovável , Amido/isolamento & purificação
14.
Artigo em Zh | MEDLINE | ID: mdl-25567442

RESUMO

OBJECTIVE: This study established a model of acoustically evoked short latency negative response (ASNR) in guinea pigs. Stereotaxic coordinate guided electrolytic lesion was applied to animal brainstem nuclei, the vestibular nucleus and the cochlear nucleus, to define the neural origin of ASNR. METHODS: Twenty four guinea pigs with normal hearing were randomly divided into the control group (8 subjects, 16 ears) and the deafened group (16 subjects, 32 ears). Each animal experienced the auditory brainstem response (ABR) test. According to the presence of ASNR, the deafened group was further divided into ASNR group and non-ASNR group. Electrolytic lesion was conducted to the vestibular nucleus and cochlear nucleus respectively, followed by ABR test. The lesion structures were verified by brainstem slice and microscope. RESULTS: In deafened group, the ASNR was elicited in 10 ears (31.3%). The ASNR was eliminated due to the electrolytic destruction to the vestibular nucleus, but it remained unchanged after the same procedure to the cochlear nucleus. CONCLUSION: It is clear that the ASNR is originated from the vestibular nucleus, but not the cochlear nucleus.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico , Acústica , Animais , Núcleo Coclear , Cobaias , Tempo de Reação , Sáculo e Utrículo , Núcleos Vestibulares
15.
Artigo em Zh | MEDLINE | ID: mdl-22883582

RESUMO

OBJECTIVE: To establish a model of ototoxicity in guinea pigs with acoustically evoked short latency negative response (ASNR) and verify the responsible organ of ASNR based on microscopic characteristics of basal membranes, saccules, utricles and ampulla canalis semicircularis of the inner ear. METHODS: Total of 45 guinea pigs were employed in the experiment, which were randomly divided into the control group (15 subjects, 30 ears) and the deafened group (30 subjects, 60 ears). Each animal experienced auditory brainstem response (ABR). A quick treatment was employed for deafened group consisting of a subcutaneous injection of kanamycin at a dose of 400 mg/kg followed by jugular vein injection of ethacrynic acid at a dose of 40 mg/kg one hour later. The animals were performed ABR test from 7 to 10 days after the drug administration. The deafened group was further divided into ASNR group and non-ASNR group based on the presence of ASNR. All the guinea pigs were sacrificed after ABR tests. The Corti organ, macula sacculi, macula utriculi and crista ampullaris were observed by light microscope. RESULTS: In the deafened group (60 ears), 3 subjects died postoperatively, 27 subjects (54 ears) provided full data. ASNR was elicited in 19 ears (35.2%, 19/54), the thresholds of ASNR were from 110 to 125 dBSPL with average of (121.7 ± 4.5) dBSPL. ASNR latency ranges were 1.80 - 2.08 ms, the average latency of thresholds were (1.93 ± 0.07) ms. The stretched preparation results: overall hair-cell density of macula saccule, macula utriculi and crista ampullaris decreased in order of normal control group, ASNR group and non-ASNR group. There was no difference between the normal group and ASNR group for cell density of macula saccule. Apart from this, statistical differences were found among other groups. CONCLUSIONS: The present study evoked ASNR in an ototoxicity guinea pig model which was profound hearing loss with normal saccular function and normal saccular hair cell density. It suggested that ASNR originates from the saccule and have no relation with cochlear, utricle and semicircular canal according to morphological study.


Assuntos
Estimulação Acústica , Surdez/fisiopatologia , Orelha Interna/fisiopatologia , Potenciais Evocados Auditivos , Animais , Potenciais Evocados Auditivos do Tronco Encefálico , Cobaias , Tempo de Reação , Sáculo e Utrículo/fisiopatologia
16.
Artigo em Zh | MEDLINE | ID: mdl-21624253

RESUMO

OBJECTIVE: To establish a model of acoustically evoked short latency negative response (ASNR) in guinea pigs, a model of profound hearing loss with normal saccular functions, and verify the correlation between ASNR and vestibular evoked myogenic potential (VEMP). METHODS: Thirty-two healthy guinea pigs were employed in the experiment, which were randomly divided into control group (16 subjects) and deafened group (16 subjects). Each animal experienced auditory and vestibular tests including auditory brainstem response (ABR), VEMP and caloric test. A quick treatment was employed for deafened group consisting of a subcutaneous injection of kanamycin at a dose of 400 mg/kg followed by a jugular vein injection of ethacrynic acid at a dose of 40 mg/kg one hour later. The animals were received ABR, VEMP and caloric test 7 - 10 days following the drug administration. The deafened group was further divided into ASNR group and non-ASNR group, based on the presence of ASNR. RESULTS: In deafened group, five subjects died postoperatively, 11 subjects (22 ears) provided full data, ASNR was elicited in eight ears (36.4%), the threshold was 120 - 130 dB SPL with mean of (124.4 ± 4.96) dB SPL. Its latency range was 1.75 - 2.60 ms with mean of (2.15 ± 0.27) ms. The mean latency of threshold was (2.34 ± 0.18) ms. All eight ASNR ears presented with VEMP. The VEMP threshold, positive and negative potential latencies proved no statistical difference (P > 0.05) between ASNR group and control group. Significant difference was detected between the VEMP presence of ASNR group and non-ASNR group (P = 0.002). There was no statistically significant correlation between VEMP and caloric test neither between ASNR and caloric test in deafened group. CONCLUSIONS: This study evoked ASNR in an ototoxicity guinea pig model which has profound hearing loss with normal saccular functions. The presence of ASNR correlated with VEMP, however, not correlated with caloric test, suggesting that ASNR and VEMP are both originated from the saccule.


Assuntos
Surdez/fisiopatologia , Potenciais Evocados Auditivos do Tronco Encefálico , Potenciais Evocados Auditivos/fisiologia , Sáculo e Utrículo/fisiologia , Potenciais Evocados Miogênicos Vestibulares , Animais , Modelos Animais de Doenças , Cobaias , Testes de Função Vestibular
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