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The neural basis of fear of heights remains largely unknown. In this study, we investigated the fear response to heights in male mice and observed characteristic aversive behaviors resembling human height vertigo. We identified visual input as a critical factor in mouse reactions to heights, while peripheral vestibular input was found to be nonessential for fear of heights. Unexpectedly, we found that fear of heights in naïve mice does not rely on image-forming visual processing by the primary visual cortex. Instead, a subset of neurons in the ventral lateral geniculate nucleus (vLGN), which connects to the lateral/ventrolateral periaqueductal gray (l/vlPAG), drives the expression of fear associated with heights. Additionally, we observed that a subcortical visual pathway linking the superior colliculus to the lateral posterior thalamic nucleus inhibits the defensive response to height threats. These findings highlight a rapid fear response to height threats through a subcortical visual and defensive pathway from the vLGN to the l/vlPAG.
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Medo , Corpos Geniculados , Camundongos Endogâmicos C57BL , Colículos Superiores , Vias Visuais , Animais , Masculino , Medo/fisiologia , Camundongos , Corpos Geniculados/fisiologia , Colículos Superiores/fisiologia , Vias Visuais/fisiologia , Substância Cinzenta Periaquedutal/fisiologia , Neurônios/fisiologia , Córtex Visual Primário/fisiologia , Percepção Visual/fisiologia , Comportamento Animal/fisiologiaRESUMO
BACKGROUND: Atrial tachycardia (AT) originating from the left atrial appendage (LAA) is uncommon and the most difficult arrhythmia to eliminate. Therefore, we present the case of a 5-year-old girl with tachycardia-induced cardiomyopathy (TIC) caused by AT originating from the LAA and successfully treated with RFCA associated to left atrial appendectomy. With resolution of AT, we observed a progressive improvement of LV function. The effectiveness and safety of this combination therapy were evaluated over a one-month follow-up period. CASE PRESENTATION: A 5 -year-old female was evaluated for three days of incessant cough and a syncopal episode. Surface echocardiography and 24-hour monitoring showed that the infant had persistent atrial tachycardia. Echocardiography revealed an enlarged tele diastolic diameter (46.1 mm) and malfunctioning (EF 28.53%) left ventricle. The location of the lesion at the apex of the LAA was further confirmed by electrophysiological study and RFCA. After RFCA, the infant's ECG monitor showed that sinus rhythm was maintained for up to 22 h. Subsequently, atrial tachycardia recurred and sinus rhythm disappeared. Finally, atrial appendectomy was performed and sinus rhythm returned to normal. CONCLUSIONS: The heart function of the infant improved and sinus rhythm was maintained, further demonstrating the safety and effectiveness of combined treatment with RFCA and atrial appendectomy after electrophysiological localization of AT from LAA to TIC.
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Cardiomiopatias , Ablação por Cateter , Pré-Escolar , Feminino , Humanos , Apendicectomia , Cardiomiopatias/cirurgia , Átrios do Coração/cirurgia , Taquicardia/cirurgiaRESUMO
BACKGROUND: Excessive NaCl intake in liquid and semi-solid food (e.g. soup, hot pot base, sauce) poses a high risk to human health, and reducing NaCl intake is a major concern for global health. RESULTS: Using the generalized Labeled Magnitude Scale (gLMS) method, the study verified the possibility of sodium reduction through oil addition. The compromised acceptance threshold (CAT) and hedonic rejection threshold (HRT) were determined. The gLMS results showed that the saltiness intensity of samples containing 0.36% NaCl and 2.29% sunflower seed oil was significantly higher than that of samples containing only 0.36% NaCl (P < 0.05). CAT and HRT results indicated that by adding 3.59% sunflower oil, the NaCl content could be reduced to a minimum of 0.14% without causing sensory rejection in bone broth samples. The quantitative descriptive analysis method was used to determine the effects of NaCl and oil concentrations on the sensory attributes of bone broth samples. Furthermore, it was used to analyze the consumer acceptability drivers in combination with the hedonic scale to optimize the formulation of reduced-salt bone broth products. Notably, sample E (0.36% NaCl, 2.29% fat) not only had a significant salt reduction effect with a 20% decrease in NaCl, but also had improved overall acceptability. CONCLUSION: This study provides theoretical guidance for designing salt-reduction cuisine within the catering and food industries, including bone broth and hot pot bases. © 2024 Society of Chemical Industry.
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Comportamento do Consumidor , Paladar , Humanos , Adulto , Óleo de Girassol/química , Feminino , Masculino , Aditivos Alimentares/análise , Aditivos Alimentares/química , Cloreto de Sódio/análise , Cloreto de Sódio/química , Adulto Jovem , Pessoa de Meia-Idade , Cloreto de Sódio na Dieta/análise , Osso e Ossos/químicaRESUMO
Selective supported catalysts have emerged as a promising approach to enhance carrier separation, particularly in the realm of photocatalytic hydrogen production. Herein, a pioneering exploration involves the loading of PdS and Pt catalyst onto g-C3N4 nanosheets to construct g-C3N4@PdS@Pt nanocomposites. The photocatalytic activity of nanocomposites was evaluated under visible light and full spectrum irradiation. The results show that g-C3N4@PdS@Pt nanocomposites exhibit excellent properties. Under visible light irradiation, these nanocomposites exhibit a remarkable production rate of 1289 µmol·g-1·h-1, marking a staggering 60-fold increase compared to g-C3N4@Pt (20.9 µmol·g-1·h-1). Furthermore, when subjected to full spectrum irradiation, the hydrogen production efficiency of g-C3N4@PdS@Pt-3 nanocomposites reaches an impressive 11,438 µmol·g-1·h-1, representing an eightfold enhancement compared to g-C3N4@Pt (1452 µmol·g-1·h-1) under identical conditions. Detailed investigations into the microstructure and optical properties of g-C3N4@PdS catalysts were conducted, shedding light on the mechanisms governing photocatalytic hydrogen production. This study offers valuable insights into the potential of these nanocomposites and their pivotal role in advancing photocatalysis.
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Objective: To construct and validate nomogram models that predict the incidence of delirium in elderly patients with non-severe SARS-CoV-2 infection. Methods: Elderly patients (≥65y) tested positive for SARS-CoV-2 infection at the hospital were included. We used the 3-min diagnostic Confusion Assessment Method for delirium diagnosis. Least absolute shrinkage and selection operator (LASSO) logistical regression analysis was performed to explore potential independent influencing factors of delirium. A predict model visualized by nomogram was constructed based on the confirmed variables. The predictive accuracy and clinical value of the model were evaluated using receiver operating characteristic (ROC) curves. Results: The data of 311 elderly patients were analyzed, of whom 73 (23.47%) patients were diagnosed with delirium. Three independent influencing factors of delirium were confirmed: age (OR1.16,1.11-1.22), Glomerular filtration rate (OR 0.98,0.97-0.99), platelet-large cell ratio (1.06,1.02-1.10). These parameters were used to create a nomogram to predict the development of delirium, which showed good predictive accuracy confirmed by the ROC curves (AUC 0.82,0.76-0.88). Conclusion: We construct a credible nomogram to predict the development of delirium in elderly patients with Non-severe SARS-CoV-2 infection. Our finding may be useful to physicians in early prevention and treatment of delirium.
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Contamination of soils by microplastics can have profound ecological impacts on terrestrial ecosystems and has received increasing attention. However, few studies have considered the impacts of soil microplastics on plant communities and none has tested the impacts of spatial heterogeneity in the horizontal distribution of microplastics in the soil on plant communities. We grew experimental plant communities in soils with either a homogeneous or a heterogeneous distribution of each of six common microplastics, i.e., polystyrene foam (EPS), polyethylene fiber (PET), polyethylene bead (HDPE), polypropylene fiber (PP), polylactic bead (PLA) and polyamide bead (PA6). The heterogeneous treatment consisted of two soil patches without microplastics and two with a higher (0.2%) concentration of microplastics, and the homogeneous treatment consisted of four patches all with a lower (0.1%) concentration of microplastics. Thus, the total amounts of microplastics in the soils were exactly the same in the two treatments. Total and root biomass of the plant communities were significantly higher in the homogeneous than in the heterogeneous treatment when the microplastic was PET and PP, smaller when it was PLA, but not different when it was EPS, HDPE or PA6. In the heterogeneous treatment, total and root biomass were significantly smaller in the patches with than without microplastics when the microplastic was EPS, but greater when the microplastic was PET or PP. Additionally, in the heterogeneous treatment, root biomass was significantly smaller in the patches with than without microplastics when the microplastic was HDPE, and shoot biomass was also significantly smaller when the microplastic was EPS or PET. The heterogeneous distribution of EPS in the soil significantly decreased community evenness, but the heterogeneous distribution of PET increased it. We conclude that soil heterogeneity in the horizontal distribution of microplastics can influence productivity and species composition of plant communities, but such an effect varies depending on microplastic chemical composition (types) and morphology (shapes).
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Nosocomial infection caused by carbapenem-resistant Klebsiella pneumonia (CRKP) infection has become a global public health problem. Human NK and NKT cells in peripheral immune responses are recognized as occupying a critical role in anti-bacterial immunity. Through performed scRNA-seq on serial peripheral blood samples from 3 patients with CRKP undergoing colonization, infection, and recovery conditions, we were able to described the immune responses of NK and NKT cells during CRKP infection and identified a mechanism that could contribute to CRKP clearance. The central player of CRKP infection process appears to be the NKT subset and CD56hiNKT subset which maintained immune competence during CRKP colonization. With time, CRKP leads to the loss of NK and CD160hiNKT cells in peripheral blood, resulting in suppressed immune responses and increased susceptibility to opportunistic infection. In summary, our study identified a possible mechanism for the CRKP invasion and to decipher the clues behind the host immune response that influences CRKP infection pathogenesis.
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Objective: The aim of this study was to investigate the efficacy of radiofrequency catheter ablation (RFCA) combined with atrial appendage (AA) resection to treat atrial tachycardia (AT) originating from the AA in children. Materials and methods: Using the Ensite three-dimensional electroanatomic mapping system, three children with AT originating from the AA were diagnosed. Clinical features and electrocardiographic (ECG) manifestations were analyzed. Ablations were performed using a cold saline-infused catheter at appendages targeting loci of AT origin under the guidance of the Ensite system. Atrial appendage resection was performed in combination with cardiac surgery, and the curative effect was evaluated. Results: The ages of the three patients were 3.5, 5.75, and 12.9 years. Two cases originated from the right atrial appendage (RAA) and one originated from the left atrial appendage (LAA). The ECG characteristics of AT from the RAA were as follows: (1) negative P waves in lead V1; (2) positive P waves in leads II, III, and aVF; (3) positive P wave in lead I with varying shapes in lead aVL; and (4) prolonged PR interval with no QRS wave after some P waves. The ECG of the LAA was characterized by (1) positive P waves in lead V1 with a bimodal pattern; (2) positive P waves in leads II, III, and aVF; and (3) negative P waves in leads I and aVL. Preoperative echocardiography showed cardiac enlargement and a decreased left ventricular ejection fraction (LVEF) in all three cases. One case was cured after RFCA, and the remaining two cases required AA resection after RFCA. No recurrence was detected at 1-18 months of follow-up, and the left ventricular end-diastolic diameter and LVEF returned to normal. Conclusion: Atrial tachycardia originating from the AA in children showed a characteristic P-wave presentation on ECG, and sustained episodes of AT resulted in tachycardia-induced cardiomyopathy. Children who are not successfully controlled by RFCA or who have a recurrence after RFCA could benefit from AA resection.
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BACKGROUND: The residents of both the agricultural and pastoral areas of Tibet share the same iodine deficiency and iodine nutrition, but the rate of thyroid goiter was significantly higher in the agricultural areas than in the pastoral areas. This project sought to determine why the populations in the iodine-deficient pastoral areas show a lower rate of thyroid goiter. METHODS: Food frequency questionnaires (FFQs) and 24 h history recalls were adopted to investigate the dietary patterns of the residents of the agricultural and pastoral areas. Meat and milk samples were collected to measure their inorganic iodine, total iodine and thyroid hormone contents using ICP-MS, AsIII-Ce4+ catalytic spectrophotometry and the Siemens' chemiluminescence method, respectively. The intake of protein, and the microelements, selenium and iron, was calculated according to their content in the food. RESULTS: The per capita daily intake of meat, dairy, and cereal in the pastoral areas was 116.7, 216.7, and 433.3 g, respectively, which are significantly higher than those in the agricultural areas (50.0, 72.2, and 375.0 g, respectively) (p < 0.05). The content of thyroid hormone in dried beef and milk in the pastoral areas was 62.6 and 13.5 µg/kg, respectively, which was significantly higher than those in the agricultural areas (25.1 and 4.1 µg/kg, respectively) (p < 0.05). The daily intake of thyroid hormone, protein and microelements, selenium and iron from foods by the residents of the pastoral areas were 10.5 µg, 99.6 g, 30.0 µg and 15.8 mg respectively, which was significantly higher than those in the agricultural areas (1.79 µg, 56.5 g, 23.8 µg and 13.2 mg, respectively) (p < 0.05). CONCLUSIONS: The significantly high intake of the food-borne thyroid hormone by the residents of the pastoral area could be the main reason the residents in the pastoral areas show a lower rate of thyroid goiter than those in the agricultural area. Moreover, the relatively high intake of protein and trace elements, selenium and iron by residents in the pastoral area could be another important factor for reducing the goiter rates.
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A cross-modal interaction may exist between the perception of saltiness and the pungency elicited by Sichuan pepper oleoresin (Spo). Thirty-one hypersensitive panelists were selected to participate in this study. Spo solutions dissolved in different NaCl concentrations, ranging from 1.25 g/L to 167.9 g/L, were used as the test samples. The rated difference from control, the generalized labeled magnitude scale (gLMS), and the time-intensity (TI) method were used to determine the detection threshold (DT), the recognition threshold (RT), the intensity, and the dynamic perception of pungent sensation. The results revealed that the pungency thresholds increased significantly (p < 0.01) in the solution with a high NaCl (167.9 g/L) concentration. Furthermore, high NaCl solutions suppressed the pungency intensity at all Spo concentrations except for 0.02 g Spo/L in water (p < 0.05). The TI and principal component analysis (PCA) results showed that an increase in the Spo concentration prolonged the duration of the pungency sensation. However, the maximum intensity, the time to reach maximum intensity, the decay time of perception, and the end time of perception of the Spo solutions ranging from 2.13 g/L to 4.69 g/L were significantly reduced at medium (42.95 g/L) and high NaCl concentrations. Since the salty and pungency sensations exhibited by NaCl and Spo are common flavor combinations in food products and dishes, studying the influence of saltiness on the dynamic perception of pungent sensation not only aids the development of oral cleaners during pungency evaluation but also presents significant theoretical and practical value in creating pungent food and cuisine based on consumer preferences.
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Sensação , Cloreto de Sódio , Percepção , Extratos Vegetais , VerdurasRESUMO
The properties of zeolitic imidazolate framework (ZIF) crystals highly depend on the structures of the low-energy surfaces, such as {110} of ZIF-8. However, the atomic/molecular configurations of the ZIF-8 {110} surfaces remain debated. In this study, the near-atomic-scale characterization of {110} surfaces of ZIF-8 is conducted by low-dose aberration-corrected transmission electron microscopy (TEM). The real-space images with mitigated surface delocalization by minimized spherical aberration of TEM, together with the solvent corrected surface energy calculations, demonstrate that the {110} surfaces of ZIF-8 crystals with an equilibrium-form rhombic morphology have a zigzag-type termination. This study provides experimental evidence to clarify the debated structure of {110} ZIF-8 surfaces and has important implications in understanding the crystal growth and surface related properties of ZIF-8.
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ETHNOPHARMACOLOGICAL RELEVANCE: Crassostrea gigas Thunberg and other oysters have been traditionally used in China as folk remedies to invigorate the kidney and as natural aphrodisiacs to combat male impotence. AIM OF THE STUDY: Erectile dysfunction (ED) has become a major health problem for the global ageing population. The aim of this study is therefore to evaluate the effect of peptide-rich preparations from C. gigas oysters on ED and related conditions as increasing evidence suggests that peptides are important bioactive components of marine remedies and seafood. MATERIALS AND METHODS: Crassostrea oyster peptide (COP) preparations COP1, COP2 and COP3 were obtained from C. gigas oysters by trypsin, papain or sequential trypsin-papain digestion, respectively. The contents of testosterone, cyclic adenosine monophosphate (cAMP) and nitric oxide (NO) and the activity of nitric oxide synthase (NOS) in mice and/or cells were measured by enzyme-linked immunosorbent assays. Real-time PCR was used to assess the expression of genes associated with sex hormone secretion pathways. The model animal Caenorhabditis elegans was also used to analyze the gene expression of a conserved steroidogenic enzyme. In silico analysis of constituent peptides was performed using bioinformatic tools based on public databases. RESULTS: The peptide-rich preparation COP3, in which >95% peptides were <3000 Da, was found to increase the contents of male mouse serum testosterone and cAMP, both of which are known to play important roles in erectile function, and to increase the activity of mouse penile NOS, which is closely associated with ED. Further investigation using mouse Leydig-derived TM3 cells demonstrates that COP3 was able to stimulate the production of testosterone as well as NO, a pivotal mediator of penile erection. Real-time PCR analysis reveals that COP3 up-regulated the expression of Areg and Acvr2b, the genes known to promote sex hormone secretion, but not Fst, a gene involved in suppressing follicle-stimulating hormone release. Furthermore, COP3 was also shown to up-regulate the expression of let-767, a well-conserved C. elegans gene encoding a protein homologous to human 17-ß-hydroxysteroid dehydrogenases. Preliminary bioinformatic analysis using the peptide sequences in COP3 cryptome identified 19 prospective motifs, each of which occurred in more than 10 peptides. CONCLUSIONS: In this paper, Crassostrea oyster peptides were prepared by enzymatic hydrolysis and were found for the first time to increase ED-associated biochemical as well as molecular biology parameters. These results may help to explain the ethnopharmacological use of oysters and provide an important insight into the potentials of oyster peptides in overcoming ED-related health issues.
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Fatores Biológicos/isolamento & purificação , Fatores Biológicos/farmacologia , Crassostrea/enzimologia , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/farmacologia , Testosterona/sangue , Animais , Caenorhabditis elegans , Células Cultivadas , Biologia Computacional/métodos , Relação Dose-Resposta a Droga , Ensaios Enzimáticos/métodos , Hidrólise , Masculino , CamundongosRESUMO
BACKGROUND: KIO3 and KI are the most common salt iodization agents. Coincidentally, iodine exists naturally in high-iodine drinking water in the form of iodide (I-) or iodate (IO3-). As an oxidizing substance, IO3- should be reduced to I- before it can be effectively used by the thyroid. However, there is a lack of systematic studies on the metabolic process of high dose KIO3in vivo. METHODS: The iodine metabolism processes in the thyroid and serum of rats after high KIO3 intake were determined using high-performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC/ICP-MS) and arsenic cerium catalytic spectrophotometry. The changes of redox activity in the serum, thyroid, liver, and kidneys were observed by detecting total antioxidative activity (TAA). RESULTS: High doses of IO3- were completely reduced to I-in vivo within 0.5â¯h. The level of organic bound iodine in the serum was stable, while the organic bound iodine in the thyroid increased to a plateau after intake of high-dose KIO3. The levels of total iodine and I- in serum and thyroid increased quickly, then all decreased after reaching the maximum absorption peak, and I- had two absorption peaks in serum. The thyroid blocking dose of I- was 0.5â¯mg/kg in rat. Additionally, high KIO3 intake did not influence the TAA in serum and other tissues. CONCLUSION: The body is able to reduce and utilize high doses of KIO3 ingested through the digestive tract. The metabolism of high KIO3in vivo is characterized by two absorption process of I- in serum and the thyroid blocking effect. Moreover, a single intake of high-dose KIO3 does not affect TAA in vivo. The results suggest that such excess IO3- may have be reduced in the digestive tract before I-â¯enters the blood.
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Antioxidantes/metabolismo , Iodatos/farmacologia , Iodo/metabolismo , Compostos de Potássio/farmacologia , Animais , Feminino , Iodatos/administração & dosagem , Iodatos/análise , Iodatos/sangue , Iodatos/farmacocinética , Iodo/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Compostos de Potássio/administração & dosagem , Compostos de Potássio/farmacocinética , Ratos Wistar , Glândula Tireoide/efeitos dos fármacos , Glândula Tireoide/metabolismoRESUMO
Terahertz (THz) communication is considered as a promising technology for the Earth-space application due to its high potential of supporting large data capacity. However, THz wave suffers extreme attenuation from absorption of water vapor (WV) molecules in the propagation path. In this work, we present a theoretical model and analyze the capacities of both inter-satellite and geostationary satellite-to-Earth station (GEO-ES) opto-electronic links operating in the 100-500 GHz band within low- and mid-latitude regions. In our work, THz frequency windows in the 140, 220, 340, and 410 GHz bands with relatively low atmospheric loss are selectively used, targeting a data capacity of 10 Gbps per gigahertz. Our analysis indicates that, in the low-latitude regions, due to high water vapor density (WVD), transmitting and receiving antennas with extremely high gains are required. On the contrary, the mid-latitude regions require less power due to comparatively lower WVD. Moreover, due to seasonal variation in the mid-latitude regions, the requirement of link power budget is tens of decibels less in winter as compared to summer. The results suggest that the establishment of GEO-ES THz links in low- and mid-latitude regions is more realistic in the sub-THz bands, such as 140 and 220 GHz, while the potential of using higher carrier frequencies above 300 GHz for inter-satellite THz links, due to the absence of WV-induced absorption, is supported.
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OBJECTIVE: To study the effect of Bcl-2 family members on experimental autoimmune thyroiditis(EAT) and explore the pathogenesis of autoimmune thyroiditis. METHODS: Twenty-four female 4-5 week old NOD-SCID mice were randomly divided into four groups(six mice in each group): control group, high iodine group, poly(I:C) group and high iodine combined with poly(I:C) group. Control group and poly(I:C) group were fed with distilled water, while the high iodine group and high iodine combined with poly(I:C) group were supplied with 0. 05% NaI in their drinking water for 16 weeks. Poly(I:C) group and high iodine combined with poly(I:C) group received intraperitoneal injection of 100 µL poly(I:C)(1 µg/µL) at monday, wednesday and friday of the 11 th and 15 th week. Serum and thyroid were obtained at the last day of the 16 th week. The EAT model was confirmed by ELISA method and pathological HE staining, the apoptosis of thyroid cell were detected by TUNEL method and Cyt-C immunocytochemistry assay, and the mRNA levels of Bcl-2 family members in thyroid were determined by real-time qPCR method. RESULTS: EAT model was established using NOD-SCID mice through high-iodine feeding combined with poly(I:C) intraperitoneal injection. The degree of cell apoptosis and the Cyt-C expression levels were positively correlated with inflammation in thyroid follicular epithelial cells. The mRNA levels of Noxa, PUMA and Bid of high iodine group and high iodine combined with poly(I:C) group were higher than those in control and poly(I:C) groups(P<0. 05). CONCLUSION: Mitochondrial apoptosis pathway is involved in the thyroid cell apoptosis of EAT induced by high iodine, and the apoptosis may be regulated by the up-regulation of Noxa, PUMA and Bid, which belong to the pro-apoptotic members of Bcl-2 family.
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Apoptose , Iodo/efeitos adversos , Glândula Tireoide/metabolismo , Tireoidite Autoimune/patologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas Reguladoras de Apoptose/genética , Feminino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas/genética , RNA Mensageiro , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real , Tireoidite Autoimune/induzido quimicamente , Tireoidite Autoimune/metabolismo , Proteínas Supressoras de Tumor/genéticaRESUMO
BACKGROUND: Mechanical and biological complications associated with implant systems happen frequently in the clinic. PURPOSE: To develop a chitosan (CS)-based thermosensitive hydrogel for sealing and lubricating purposes in dental implant system. MATERIALS AND METHODS: In this study, a thermosensitive hydrogel made up of CS, ß-glycerophosphate pentahydrate (ß-GP), and povidone-iodine (PVP-I), called CS/ß-GP/PVP-I thermosensitive hydrogel, was fabricated. Three experimental groups with different volume ratios of CS to ß-GP were prepared, namely 16/4, 13/7, and 10/10 groups. The surface topography of the different groups and their physicochemical characteristics were examined by SEM, FTIR, and X-ray diffraction analysis. The cytotoxicity of the hydrogel was examined by CCK-8 test. In vitro antibacterial efficiency was analyzed by the spread plate method. Sealing ability was detected by incubating two-piece implants in Escherichia coli suspension. Lubricating ability of the hydrogel was evaluated by the removal torque test with a calibrated digital torque meter. RESULTS: The CS/ß-GP/PVP-I thermosensitive hydrogel was fabricated and showed a highly porous structure under SEM. An in vitro cytotoxicity test demonstrated that 13/7 group displayed no cytotoxicity. Furthermore, all three groups showed obviously antibacterial effects. In the sealing ability test, 16/4 group showed the best sealing ability. The removal torque of 16/4 group and 13/7 group was significantly greater than control group. CONCLUSIONS: Based on our findings, it could be concluded that the thermosensitive and antibacterial CS/ß-GP/PVP-I hydrogel with sealing and lubricating ability was successfully prepared. The hydrogel had better sealing and lubricating effects when the volume ratio of CS to ß-GP was 16/4.
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Quitosana , Implantes Dentários , Antibacterianos , Hidrogel de Polietilenoglicol-Dimetacrilato , Hidrogéis , TemperaturaRESUMO
Polyploids are organisms whose genomes consist of more than two complete sets of chromosomes. Both autopolyploids and allopolyploids may display polysomic inheritance. A peculiarity of polysomic inheritance is multivalent formation during meiosis resulting in double-reduction, which occurs when sister chromatid fragments segregate into the same gamete. Double-reduction can result in gametes carrying identical-by-descent alleles and slightly increasing homozygosity. This will cause the genotypic frequencies to deviate from expected values and will thus bias the results of standard population genetic analytical methods used in molecular ecology and selective breeding. In this study, we extend existing double-reduction models to account for any even level of ploidy, and derive the symbolic expressions for genotypic frequencies via two methods. Inbreeding coefficients and heterozygosity under double-reduction and inbreeding are also calculated. Numerical solutions obtained by computer simulations are compared with analytical solutions predicted by the model to validate the model.
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Alelos , Frequência do Gene , Genótipo , Padrões de Herança , Modelos Genéticos , Poliploidia , Algoritmos , Heterozigoto , Endogamia , ZigotoRESUMO
Morphology control of anisotropic nanocrystals is important for tuning shape-dependent physicochemical properties, but the anisotropic growth mechanism remains unclear. Here we investigate the formation of the Au penta-twinned nanorod by liquid cell transmission electron microscopy. It is found that a truncated decahedron forms in the absence of cetyltrimethylammonium bromide (CTAB), whereas in the presence of CTAB, a penta-twinned nanorod forms by producing {100} facets via the reentrant groove and selectively inhibiting atom addition to {100} facets. Density functional theory simulations show that the partial relief of strain energy of the decahedron is caused by the adsorption of Br- ions. Moreover, the selective adsorption of CTAB lowers the surface energy of {100} facets, thus enhancing the nanorod growth. Our work points out the importance of the synergy of strain and surface energy, which provide an in-depth insight into the anisotropic growth of nanorods and lay foundations for the controlled synthesis of nanomaterials.
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Water-cage clusters encapsulating guest molecules are the basic components of hydrate crystal structures. Herein, we investigated the fusion process from bi-cages to tri-cages to probe the nucleation mechanism at the initial stage of CH4 hydrate formation by employing dispersion-corrected density functional theory. We found that tri-cages possess high stability by sharing three, rather than two, polygonal faces. In addition, any mono-cage combined with a nonstandard 4151062 cage could achieve considerable stability regardless of which face is shared; this finding illustrates that 4151062 cages are more likely to appear at the early stages of CH4 hydrate nucleation than other nonstandard cages. We then simulated the Raman spectra of CH4 molecules in water-cage to characterize the spectral characteristics of the CH4 hydrate. The C-H symmetric stretching frequency of encapsulated CH4 molecules red-shifted with increasing mono-cage size, which follows the prediction of the "loose cage-tight cage" model. The symmetric stretching vibrational frequencies of trapped CH4 molecules in the tri-cage revealed a clear red-shift compared with those in the component mono- and bi-cages. The cage fusion process and spectroscopic properties described in this work are expected to provide new atomistic insights into CH4 hydrates at the initial nucleation stage.
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The aim of the study was to investigate correlations among inflammatory cytokines, nitric oxide (NO) level, urine protein, renal function and blood pressure in peripheral blood of patients with hypertensive disorder complicating pregnancy (HDCP). A total of 60 patients diagnosed with HDCP in the Obstetrics Department of Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology from May 2016 to April 2017 were selected. The patients were divided into the HDCP (n=20), mild pre-eclampsia (n=20) and severe pre-eclampsia (n=20) groups. Additionally, 20 healthy pregnant women were selected as the control group. General data of the patients were collected. NO, renal function and 24-h urine protein were measured. The systolic and diastolic blood pressure, C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the HDCP group was significantly higher than that in the control group. The CRP, TNF-α and IL-6 levels in the pre-eclampsia groups were higher than those in the gestational hypertension group (P<0.05). The NO level in peripheral blood of patients in the pre-eclampsia groups was lower than that in the gestational hypertension group (P<0.05). The levels of 24-h urine protein, homocysteine (Hcy), cystatin-C (Cys-C), serum creatinine (SCr), urea and ß2 microglobulin in the pre-eclampsia groups were higher than those in the gestational hypertension group (P<0.05). Gestational age and the levels of baseline blood pressure, inflammatory cytokines, 24-h urine protein and renal function have independent predictive value for the occurrence of HDCP (P<0.05). The results show that, 24-h urine protein, renal function and inflammatory cytokines are closely correlated with the occurrence of HDCP, which can reflect the severity and prognosis of the disease to a certain extent. In addition, it has important reference value for the assessment and treatment of the disease.