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1.
Zhonghua Nei Ke Za Zhi ; 59(4): 297-302, 2020 Apr 01.
Artículo en Zh | MEDLINE | ID: mdl-32209196

RESUMEN

Objective: To study the clinical characteristics and classification of gastric neuroendocrine neoplasm(NEN) and prognostic factors of mixed adenoneuroendocrine carcinoma (MANEC) and gastric neuroendocrine carcinoma(NEC). Methods: A total of 148 gastric NENs were divided into type Ⅰ, type Ⅱ and type Ⅲ based on the classification of European Neuroendocrine Tumor Society (ENETS). Kaplan-Meier test and Cox regression model were used in univariate and multivariate survival analysis in 108 cases with pathological G3 gastric NEN. Results: In this study, the percentages of type Ⅰ, type Ⅱ and type Ⅲ were 25.0%(37), 3.4%(5) and 71.6%(106) respectively. Among type Ⅰ patients, 28(75.7%) lesions were located in gastric fundus or body, 29(78.4%) had bumps. Lymph node involvement was found in 4 (10.8%) patients. Twenty-six (70.3%) patients received endoscopic treatment and 11 (29.7%) with surgery. All 5 type Ⅱ patients presented lesions in gastric fundus or body, including 4 with ulcers, who were all treated by endoscope. Three type Ⅱ patients had gastrinoma, and 2 combined with multiple endocrine neoplasmⅠ. In type Ⅲ patients, 56(52.8%) showed ulcerative lesions. The majority of patients (102, 96.2%) had a single lesion, 94(88.7%) with lymph node or other organ metastasis. In this study, no deaths were reported in gastric NEN with a pathological grade of G1 or G2. The mortality rate was 38.9%(42/108) in patients with G3 NEN. Survival analysis suggested that age, metastasis of tumor were associated with poor prognosis (P=0.041, 0.025). Conclusions: Patients with gastric NEN have heterogenous clinical presentations according to gender, age, endoscopic features, infiltration and metastasis, and pathological grade. Aging and metastasis are negative prognostic factors of G3 gastric NEN.


Asunto(s)
Tumores Neuroendocrinos/patología , Neoplasias Gástricas/patología , China/epidemiología , Neoplasias Gastrointestinales/mortalidad , Neoplasias Gastrointestinales/patología , Humanos , Tumores Neuroendocrinos/mortalidad , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/mortalidad , Análisis de Supervivencia
2.
Br J Anaesth ; 122(1): 141-149, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30579393

RESUMEN

BACKGROUND: Previous studies suggest that dexmedetomidine has a protective effect against local anaesthetic-induced nerve injury in regional nerve blocks. Whether this potentially protective effect exists in the context of diabetes mellitus is unknown. METHODS: A diabetic state was established in adult male Sprague-Dawley rats with intraperitoneal injection of streptozotocin. Injections of ropivacaine 0.5%, dexmedetomidine 20 µg kg-1 (alone and in combination), or normal saline (all in 0.2 ml) were made around the sciatic nerve in control and diabetic rats (n=8 per group). The duration of sensory and motor nerve block and the motor nerve conduction velocity (MNCV) were determined. Sciatic nerves were harvested at post-injection day 7 and assessed with light and electron microscopy or used for pro-inflammatory cytokine measurements. RESULTS: Ropivacaine and dexmedetomidine alone or in combination did not produce nerve fibre damage in control non-diabetic rats. In diabetic rats, ropivacaine induced significant nerve fibre damage, which was enhanced by dexmedetomidine. This manifested with slowed MNCV, decreased axon density, and decreased ratio of inner to outer diameter of the myelin sheath (G ratio). Demyelination, axon disappearance, and empty vacuoles were also found using electron microscopy. An associated increase in nerve interleukin-1ß and tumour necrosis factor-α was also seen. CONCLUSIONS: Ropivacaine 0.5% causes significant sciatic nerve injury in diabetic rats that is greatly potentiated by high-dose dexmedetomidine. Although the dose of dexmedetomidine used in this study is considerably higher than that used in clinical practice, our data suggest that further studies to assess ropivacaine (alone and in combination with dexmedetomidine) use for peripheral nerve blockade in diabetic patients are warranted.


Asunto(s)
Anestésicos Locales/toxicidad , Dexmedetomidina/toxicidad , Diabetes Mellitus Experimental/complicaciones , Traumatismos de los Nervios Periféricos/inducido químicamente , Ropivacaína/toxicidad , Nervio Ciático/efectos de los fármacos , Adyuvantes Anestésicos/toxicidad , Animales , Citocinas/biosíntesis , Diabetes Mellitus Experimental/fisiopatología , Neuropatías Diabéticas/etiología , Neuropatías Diabéticas/fisiopatología , Sinergismo Farmacológico , Mediadores de Inflamación/metabolismo , Masculino , Bloqueo Nervioso/efectos adversos , Bloqueo Nervioso/métodos , Conducción Nerviosa/efectos de los fármacos , Traumatismos de los Nervios Periféricos/etiología , Traumatismos de los Nervios Periféricos/fisiopatología , Ratas Sprague-Dawley , Nervio Ciático/lesiones
3.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e941-e947, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29285805

RESUMEN

Atmospheric ammonia in animal housing is reported to have adverse effects on livestock performance and animal health. Previous experiments have found that 75 ppm ammonia reduced the production performance and altered body fat distribution quality of broilers. In this study, we examined the body fat distribution, serum metabolites and lipid metabolism gene expression of broiler exposed to ammonia. A total of 400 chickens were randomly allocated to four groups with four replicates and received ammonia treatments at 0, 25, 50 and 75 ppm, respectively, for 3 weeks. The average daily feed intake and weight gain were decreased when broiler was exposed to ammonia concentration exceeding 50 ppm (p < .05). The increased abdominal fat and reduced thickness of subcutaneous adipose were found in broilers of 75 ppm group (p < .05). When ammonia exceeded 50 ppm, the content of fat in breast muscle of broiler was increased, and when ammonia was higher than 25 ppm, the fat in liver was increased (p < .05). It showed that the fat content in liver was a sensitive index for broilers exposed to ammonia. Furthermore, ammonia exposure had no significant effect on total cholesterol and triglyceride in serum, but significantly increased the relative mRNA expression of acetyl-CoA carboxylase (p = .046) and malic enzyme in liver (p = .038), which indicated that ammonia exposure may increase the de novo fat synthesis in liver. In addition, ammonia increased the high-density lipoprotein cholesterol (p = .02) and activity of hepatic lipase in serum (p < .001), which indicated that ammonia exposure may improve the transportation of cholesterol to liver. To conclude, our results indicated that ammonia exposure might increase the de novo fat synthesis in liver and increased the transportation of cholesterol to liver. In addition, the concentration of ammonia in poultry house should be limited lower than 25 ppm based on the variation of hepatic fat content.


Asunto(s)
Amoníaco/toxicidad , Pollos , Regulación de la Expresión Génica/efectos de los fármacos , Metabolismo de los Lípidos/genética , Hígado/enzimología , Contaminación del Aire Interior , Amoníaco/administración & dosificación , Animales , Distribución de la Grasa Corporal , Pollos/sangre , Pollos/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Vivienda para Animales , Lipasa/metabolismo , Lípidos/sangre , Lipoproteínas/sangre , Masculino , ARN Mensajero
4.
J Biol Regul Homeost Agents ; 31(3): 697-703, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28956420

RESUMEN

This study aims to assess the early diagnosis of mouse atherosclerotic plaque through targeted ultrasound molecular imaging. Forty Apolipoprotein E-deficient (ApoE-/-) mice and 40 C57BL/6 wild type mice were randomly divided into 4 groups, 20 mice per group. Mice included in the study group were fed with high cholesterol diet for 20 weeks, after which the targeted ultrasound microbubbles were prepared. The mice with atherosclerotic plaque were studied with targeted ultrasound molecular imaging in comparison with red oil O staining. The results of targeted ultrasound molecular imaging of atherosclerotic plaque indicate that the GP Ib and GP IIb/IIIa are viable biomarkers for early diagnosis of vulnerable atherosclerotic plaque. The targeted ultrasound molecular imaging is worth studying in order to identify the atherosclerotic progress as a noninvasive effective identification method which could be used widely.


Asunto(s)
Aterosclerosis/diagnóstico por imagen , Aterosclerosis/metabolismo , Placa Aterosclerótica/diagnóstico por imagen , Placa Aterosclerótica/metabolismo , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Ultrasonografía , Animales , Aterosclerosis/genética , Biomarcadores/metabolismo , Modelos Animales de Enfermedad , Ratones , Ratones Noqueados , Placa Aterosclerótica/genética , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/genética
5.
Clin Exp Dermatol ; 41(7): 792-7, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27443265

RESUMEN

BACKGROUND: In humans, dermal papillae cells (DPCs) are surrounded by basal membranes. However, conventional in vitro culture conditions for DPCs do not include extracellular matrix (ECM). AIM: To investigate the effects of different ECM types on the characteristics of cultured human DPCs. METHODS: Freshly isolated human DPCs were inoculated onto plates precoated with type IV collagen, fibronectin, Matrigel or hyaluronate. Cell migration, growth and viability were measured. Real-time quantitative (q)PCR and western blotting were used to detect the influence of different ECM types on the expression of DPC-specific biomarkers. RESULTS: In planar culture, type IV collagen and fibronectin had a beneficial effect on the migration, aggregation and viability of DPCs, in contrast to Matrigel and hyaluronate. Real-time qPCR revealed that significantly increased expression of mRNA was seen only for neural cell adhesion molecule (NCAM) and α-smooth muscle actin (α-SMA) in the Matrigel group, whereas versican, NCAM and α-SMA all decreased significantly in the hyaluronate group. In the type IV collagen and fibronectin groups, mRNA expression of the above genes did not change significantly. Western blotting indicated that there were no significant differences in expression of the above proteins between the four groups and the control group. CONCLUSION: In planar culture, exogenous ECM types (Matrigel, type IV collagen, hyaluronate and fibronectin) changed the growth characteristics of DPCs, but they did not affect the characteristics associated with the biological functions of DPCs.


Asunto(s)
Colágeno Tipo IV/farmacología , Colágeno/farmacología , Dermis/efectos de los fármacos , Matriz Extracelular/química , Fibronectinas/farmacología , Ácido Hialurónico/farmacología , Laminina/farmacología , Proteoglicanos/farmacología , Técnicas de Cultivo de Célula , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Dermis/citología , Combinación de Medicamentos , Humanos
6.
Genet Mol Res ; 13(3): 7037-51, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24615110

RESUMEN

The influence of warm day and cool night conditions on induction of spikes in Phalaenopsis orchids has been studied with respect to photosynthetic efficiency, metabolic cycles and physiology. However, molecular events involved in spike emergence induced by warm day and cool night conditions are not clearly understood. We examined gene expression induced by warm day and cool night conditions in the Phalaenopsis hybrid Fortune Saltzman through suppression subtractive hybridization, which allowed identification of flowering-related genes in warm day and cool night conditions in spikes and leaves at vegetative phase grown under warm daily temperatures. In total, 450 presumably regulated expressed sequence tags (ESTs) were identified and classified into functional categories, including metabolism, development, transcription factor, signal transduction, transportation, cell defense, and stress. Furthermore, database comparisons revealed a notable number of Phalaenopsis hybrid Fortune Saltzman ESTs that matched genes with unknown function. The expression profiles of 24 genes (from different functional categories) have been confirmed by quantitative real-time PCR in induced spikes and juvenile apical leaves. The results of the real-time PCR showed that, compared to the vegetative apical leaves, the transcripts of genes encoding flowering locus T, AP1, AP2, KNOX1, knotted1-like homeobox protein, R2R3-like MYB, adenosine kinase 2, S-adenosylmethionine synthetase, dihydroflavonol 4-reductase, and naringenin 3-dioxygenase accumulated significantly higher levels, and genes encoding FCA, retrotransposon protein Ty3 and C3HC4-type RING finger protein accumulated remarkably lower levels in spikes of early developmental stages. These results suggested that the genes of two expression changing trends may play positive and negative roles in the early floral transition of Phalaenopsis orchids. In conclusion, spikes induced by warm day and cool night conditions were complex in Phalaenopsis orchids; nevertheless, several molecular flowering pathway-related genes were found. The acquired data form the basis for a molecular understanding of spike induction by warm day and cool night conditions in Phalaenopsis orchids.


Asunto(s)
Flores/genética , Regulación de la Expresión Génica de las Plantas , Orchidaceae/genética , Fotoperiodo , Técnicas de Hibridación Sustractiva , Temperatura , Etiquetas de Secuencia Expresada , Flores/metabolismo , Perfilación de la Expresión Génica , Biblioteca de Genes , Redes y Vías Metabólicas , Orchidaceae/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Transducción de Señal , Transcripción Genética
7.
Genet Mol Res ; 13(3): 5982-94, 2014 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-25117357

RESUMEN

Warm day and cool night conditions significantly induce reproductive spike formation in Phalaenopsis plants; hence, determining the flowering mechanism regulating the reproductive transition is important. Flowering locus T (FT) plays important roles in flowering induction in several plants. To explore spike induction by warm days and cool nights in Phalaenopsis orchids, we isolated the FT (PhFT) from Phalaenopsis hybrid Fortune Saltzman. The cDNA of PhFT was 809-bp long and contained a 531-bp open reading frame encoding a putative protein of 176 amino acids, a 58-bp 5'-untranslated region (UTR), and a 220-bp 3'-UTR. The predicted molecular mass of PhFT was 19.80 kDa, with an isoelectric point of 8.68. The PhFT was predicted to possess the conserved functional regions of the phosphatidylethanolamine-binding protein superfamily. Nucleotide sequence data indicated that PhFT contained 3 introns and 4 exons. Sequence alignment and phylogenetic analyses of PhFT revealed high homology to the FT proteins of Cymbidium goeringii and Oncidium Gower Ramsey. Quantitative real-time polymerase chain reaction analysis indicated that PhFT mRNA was expressed in roots, apical leaves, mature leaves, and flowers. In flowers, PhFT was expressed more in developing floral buds than in mature flowers and was predominantly expressed in ovaries and petals. Ectopic expression of PhFT in Arabidopsis ft-1 mutants showed novel early-flowering phenotypes that lost their siliques. Our results indicated that the ectopic expression of PhFT could partially complement the late flowering defect in transgenic Arabidopsis ft-1 mutants. Our findings suggest that PhFT is a putative FT homolog in Phalaenopsis plants that regulates flowering transition.


Asunto(s)
Flores/genética , Genes de Plantas , Orchidaceae/genética , Sitios de Carácter Cuantitativo , Secuencia de Aminoácidos , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Secuencia de Bases , ADN Complementario/química , ADN Complementario/genética , Flores/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas , Orden Génico , Prueba de Complementación Genética , Datos de Secuencia Molecular , Orchidaceae/clasificación , Orchidaceae/crecimiento & desarrollo , Fenotipo , Filogenia , Alineación de Secuencia
8.
Phys Rev E ; 108(6-2): 065208, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38243492

RESUMEN

Recent studies have revealed the significant influence of finite resistivity on high-energy-density plasmas, contrary to the previous findings of Jukes [J. Fluid Mech. 16, 177 (1963)0022-112010.1017/S0022112063000677]. This paper reexamines Jukes' theory in the context of magneto-Rayleigh-Taylor instability in magnetohydrodynamics with finite resistivity represented by η. The inadequacy of Jukes' approach due to an erroneous boundary condition is demonstrated, and it is shown that although the theory provides some physical insights, it fails to capture crucial features. The dispersion relation proposed in this study highlights that larger growth rates tend to diffuse the magnetic field rapidly, negating its suppressive effect. Moreover, the Atwood number has a significant influence on the growth-rate curves' shape, which differs from those of viscous or elastic flows and ideal magnetohydrodynamics. Additionally, long wavelengths grow proportionally to η^{1/3}, while α indicating growth rates behaves classically when the magnetic field is entirely diffused.

9.
Artículo en Zh | MEDLINE | ID: mdl-36878505

RESUMEN

Objective: To investigate the diagnosis and treatment of Chiari malformation patients with hoarseness and other otorhinolaryngological symptoms. Methods: The clinical data of 18 patients of Chiari malformation with hoarseness were retrospectively collected, which was composed of 5 men and 13 women, aged 3-71 with median age of 52. All the patients were admitted to the Affiliated Hospital of Qingdao University from January 1989 to January 2020. All patients underwent brain MRI and laryngoscopy. The patient's symptoms and first diagnosis department, diagnosis time, total course of disease, hoarseness course, diagnosis and treatment, and postoperative recovery time were summarized. Follow-up time was 3-16 years, with median follow-up time of 6.5 years. Descriptive methods were used for analysis. Results: The first visit departments of 18 patients included neurology (9 cases), otorhinolaryngology head and neck surgery (5 cases), pediatrics (2 cases), orthopedics (1 case) and respiratory department (1 case). Except for the 7 cases in neurology department, the other 11 patients were not diagnosed in time. The disease duration of 18 patients with Chiari malformation ranged from 2 months to 5 years, and hoarseness was present from 20 days to 5 years. After diagnosis, 9 patients underwent posterior fossa decompression surgery, and 1 of them underwent syrinx drainage at the same time. The symptoms of 8 cases improved significantly after operation, with the improvement time from 1 to 30 days. In addition, 9 patients chose conservative treatment, among whom 8 had no improvement in symptoms and 6 progressed. Conclusions: Posterior fossa decompression is an effective treatment for Chiari malformation, and the prognosis is good. Timely diagnosis and treatment can improve the prognosis of patients.


Asunto(s)
Tratamiento Conservador , Ronquera , Masculino , Humanos , Femenino , Niño , Ronquera/diagnóstico , Ronquera/etiología , Estudios Retrospectivos , Drenaje , Laringoscopía
10.
Nat Cell Biol ; 25(8): 1223-1234, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37443288

RESUMEN

SARS-CoV-2 infection causes COVID-19. Several clinical reports have linked COVID-19 during pregnancy to negative birth outcomes and placentitis. However, the pathophysiological mechanisms underpinning SARS-CoV-2 infection during placentation and early pregnancy are not clear. Here, to shed light on this, we used induced trophoblast stem cells to generate an in vitro early placenta infection model. We identified that syncytiotrophoblasts could be infected through angiotensin-converting enzyme 2 (ACE2). Using a co-culture model of vertical transmission, we confirmed the ability of the virus to infect syncytiotrophoblasts through a previous endometrial cell infection. We further demonstrated transcriptional changes in infected syncytiotrophoblasts that led to impairment of cellular processes, reduced secretion of HCG hormone and morphological changes vital for syncytiotrophoblast function. Furthermore, different antibody strategies and antiviral drugs restore these impairments. In summary, we have established a scalable and tractable platform to study early placental cell types and highlighted its use in studying strategies to protect the placenta.


Asunto(s)
COVID-19 , Embarazo , Femenino , Humanos , COVID-19/metabolismo , Placenta/metabolismo , Trofoblastos , Enzima Convertidora de Angiotensina 2/metabolismo , SARS-CoV-2 , Diferenciación Celular
11.
Eur Rev Med Pharmacol Sci ; 26(5): 1618-1624, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35302208

RESUMEN

OBJECTIVE: Tracheal intubation under general anesthesia is more likely to aggravate the injury of the cervical spine and spinal cord. We aim to explore the effect of dexmedetomidine combined with intubating laryngeal mask airway (ILMA) on anesthesia and stress response in patients with a cervical spine injury. PATIENTS AND METHODS: One hundred twenty patients were retrospectively allocated into the control group (midazolam + ILMA) and intervention group (dexmedetomidine + ILMA). Their hemodynamics at T1 (before anesthesia induction), T2 (1 minute after anesthesia induction), T3 (immediately after intubation), and T4 (1 min after successful intubation) were also compared. RESULTS: The heart rate (HR) and mean arterial pressure (MAP) of patients in the observation group were lower than those in the control group from T3 to T4 (both p = 0.000). Ramsay's score in the observation group was higher than the control group from T3 to T4 (both p= 0.000). No difference was observed in PaO2, PaCO2, and pH between the 2 groups. The level of serum cortisol (COR), plasma epinephrine (E), and norepinephrine (NE) in the observation group were lower than in the control group (p < 0.05) after induction. CONCLUSIONS: Dexmedetomidine combined with ILMA could improve the first intubation success rate and tolerance in patients with cervical spine injury by maintaining stable hemodynamics and reducing the stress response of patients.


Asunto(s)
Dexmedetomidina , Máscaras Laríngeas , Anestesia General , Vértebras Cervicales/cirugía , Humanos , Intubación Intratraqueal , Estudios Retrospectivos
12.
Phys Rev E ; 104(2-2): 025110, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34525601

RESUMEN

Rayleigh-Taylor instability (RTI) has become a powerful tool for determining the mechanical properties of materials under extreme conditions. In this paper, we first present the exact and approximate linear dispersion relations for RTI in viscoelastic materials based on the Maxwell and Kelvin-Voigt models. The approximate dispersion relation produces good predictions of growth rates in comparison with the exact one. The motion of the interface in Maxwell flow is mainly controlled by viscosity and elasticity dominates this behavior in Kelvin-Voigt flow. Since elasticity plays a distinct role from viscosity, cutoff wavelengths arise only in Kelvin-Voigt flow. The variation of the maximum growth rates and their corresponding wave numbers are also carefully studied. For both types of materials, viscosity suppresses the growth of instability, while elasticity speeds it up. This is at odds with the well-known understanding that elasticity suppresses hydrodynamic instabilities. The dependence of the maximum growth rate on slab thickness is also investigated for RTI in both types of flow, since the metal slab as a pusher has been extensively employed in high-energy-density physics. The model presented here allows study of more realistic situations by considering convergent effects and shock wave interactions, for the traditional potential flow theory is not suitable. To summary, it is able to provide guidances for future experimental designs for studies of materials under high strain and high strain rate conditions, as well as allow us to study RTI theoretically in more complicated conditions.

13.
Phys Rev E ; 101(5-1): 053110, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32575244

RESUMEN

We first derive the exact dispersion relation for viscous Rayleigh-Taylor instability in the presence of a horizontal magnetic field using a decomposition method, and we find that the horizontal magnetic field contributes to the generation of vorticity inside the flow, thereby further distorting the velocity field. This differs from the previous view of the horizontal magnetic field behaving as a surface-tension-like force that does not produce any vorticity in inviscid flow. Vorticity transport is also investigated. The well-known approximate dispersion relation yields growth rates based on an irrotational approximation with a maximum error of 19% in comparison with the exact rates. Furthermore, we investigate the physics of the viscous Richtmyer-Meshkov instability in the presence of a magnetic field, and we find that the presence of the magnetic field leads to the generation of more eigenvalues, thereby modifying the motion of the interface. Comparisons confirm that the viscosity and magnetic field both play fundamental roles in interface behavior, and it is clarified that the behaviors of the interface for viscous Richtmyer-Meshkov instability become in agreement with the numerical simulations. The dependences of the eigenvalues on the viscosities and densities of the fluids, as well as on the magnetic field, are also discussed. Finally, we analyze the evolution of the decay modes to investigate the rotationality of the velocity fields.

14.
Phys Rev E ; 102(2-1): 023112, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32942506

RESUMEN

In this paper, the rotational part of the disturbance flow field caused by viscous Rayleigh-Taylor instability (RTI) at the cylindrical interface is considered, and the most unstable mode is revealed to be three-dimensional for interfaces of small radii R. With an increase in R, the azimuthal wave number of the most unstable mode increases step by step, and the corresponding axial wave number increases as well at each step of the azimuthal wave number. When the amplitude of the wave-number vector is much larger or much smaller than 1/R, the cylindrical RTI is close to the semi-infinite planar viscous RTI limit or the finite-thickness creeping-flow RTI limit, respectively. The effect of the viscosity ratio is double-edged; it may enhance or suppress the cylindrical RTI, depending on R and the amplitude range of the wave-number vector.

15.
Acta Gastroenterol Belg ; 83(4): 527-531, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33321007

RESUMEN

OBJECTIVE: This study aimed to discuss the effects of appetite-conditioned reflex stimulation on the early enteral nutrition (EEN) tolerance, complications, and postoperative hospital stay in patients who underwent surgery. METHODS: Seventy patients who underwent laparoscopic radical resection of colorectal cancer surgery in our hospital between February and December 2017 were randomly divided into a stimulated appetite group (experimental group, including visual stimulation, nasal stimulation, taste stimulation and hearing stimulation) and a control group (n = 35). Both groups received EEN. EEN tolerance, complications, and postoperative hospital stay were then compared between the groups. RESULTS: Sixty-six patients, including 34 in the experimental group and 32 in the control group, completed the relevant experiment. The experimental group had significantly lower incidence rates of nausea, vomiting, bloating, use of prokinetic drugs, and gastric tube replacement (P < 0.05), and shorter tolerable regular eating time (5.0 ± 1.0 d vs 6.4 ± 1.9 d, P < 0.05) and postoperative hospital stay (7.0 ± 2.0 d vs 8.0 ± 1.8 d, P < 0.05) than the control group. No significant difference in complication rate was detected (P > 0.05). CONCLUSION: Appetite-conditioned reflex stimulation can improve EEN tolerance, decrease the risk of complications, and shorten ordinary diet recovery time and hospital stay.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Nutrición Enteral , Apetito , Condicionamiento Clásico , Humanos , Tiempo de Internación , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control
16.
Poult Sci ; 98(3): 1403-1409, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30285152

RESUMEN

Studies have shown that supplementing probiotics in a nasal spray can provide prophylaxis against upper respiratory tract infections. Previously, we found that spraying with Bacillus reduced the concentration of atmospheric ammonia and airborne microbiological aerosols in broiler houses. In the present study, we evaluated the effects of spraying with Bacillus amyloliquefaciens on the respiratory mucosal barrier in broilers. Two trails were conducted simultaneously in four environmentally controlled chambers. In each trail, 320 1-d-old male broilers were randomly assigned to control (CON) and B. amyloliquefaciens (BAQ) group. Eight cages containing 20 birds per cage were placed in two chambers. The BAQ group chambers were sprayed with B. amyloliquefaciens at 4 × 109 CFU/m2 each day for 42 d. Spraying with B. amyloliquefaciens increased average daily gain and average daily feed intake in broilers (P < 0.01), but had no effects on FCR (P > 0.05). The relative weights of the bursa (21 d) and spleen (42 d) were higher in the BAQ group (P < 0.05). The serum IgG, IgM (21 d), and IgA, Ig M (42 d) levels were improved in BAQ group (P < 0.05). The sIgA levels in tracheal lavage fluid were significantly higher in the BAQ group than the CON group (P < 0.05). Furthermore, treatment with BAQ downregulated IL-6 and IFN-γ (P < 0.05), but upregulated IL-2, occludin, and mucin-2 (P < 0.05). In addition, the number of acidic goblet cells was significantly higher in the tracheas of treated broilers than untreated broilers (P < 0.05). In conclusion, spraying with B. amyloliquefaciens may help to enhance the growth performance and improve the respiratory mucosal barrier in broiler chickens.


Asunto(s)
Bacillus amyloliquefaciens , Pollos/crecimiento & desarrollo , Pollos/inmunología , Probióticos/administración & dosificación , Mucosa Respiratoria/fisiología , Crianza de Animales Domésticos/métodos , Animales , Citocinas , Ingestión de Alimentos , Inmunoglobulinas/sangre , Masculino , Tamaño de los Órganos
18.
Phys Rev E ; 97(6-1): 063109, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30011457

RESUMEN

In the previous studies of Rayleigh-Taylor instability, different methods were used to consider the effects of elasticity, viscosity, and magnetic fields. In this paper, a unified method, which was first used for fluids, is validated for different physical models, where the unstable mode is decomposed into an irrotational part and a rotational part, and the latter one includes the effects of nonconservative forces and constitutive relations. Previous results of solid and liquid with or without the effects of magnetic fields and finite thickness can be easily recovered after applying the corresponding interface boundary conditions. In addition, new approximate but analytical solutions of the growth rates for a semi-infinite solid-solid interface and solid-fluid interface are obtained with substantially improved accuracy in comparison with the previous ones.

19.
Hum Exp Toxicol ; 36(8): 802-812, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27596071

RESUMEN

Nano nickel oxide (NiO), widely used in industry, has recently been discovered to have pulmonary toxicity. However, no subchronic exposure studies about nano NiO-induced pulmonary fibrosis have been reported. The objective of this study was to investigate pulmonary fibrosis induced by nano NiO and its potential mechanism in rats. Male Wistar rats ( n = 40, 200-240 g) were randomized into control group, nano NiO groups (0.015, 0.06, and 0.24 mg/kg), and micro NiO group (0.024 mg/kg). All rats were killed to collect lung tissue after intratracheal instillation of NiO particles twice a week for 6 weeks. To identify pulmonary fibrosis, Masson trichrome staining, hydroxyproline content, and collagen protein expression were performed. The results showed widespread lung fibrotic injury in histological examination and increased content of hydroxyproline, collagen types I and III in rat lung tissue exposed to nano NiO. To explore the potential pulmonary fibrosis mechanism, transforming growth factor beta 1 (TGF- ß1) content was measured by enzyme-linked immunosorbent assay, and the messenger RNA expression of key indicators was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The TGF- ß1 content was increased in nano NiO exposure groups, as well as the upregulated gene expression of TGF- ß1, Smad2, Smad4, matrix metalloproteinase, and tissue inhibitor of metalloproteinase. The findings indicated that nano NiO could induce pulmonary fibrosis, which may be related to TGF- ß1 activation.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Níquel/toxicidad , Fibrosis Pulmonar/inducido químicamente , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Factor de Crecimiento Transformador beta1/genética
20.
Artículo en Inglés | MEDLINE | ID: mdl-25871202

RESUMEN

A model is presented for the linear Rayleigh-Taylor instability taking place at the early stage of acceleration of an elastic-plastic solid, when the shock wave is still running into the solid and is driven by a time varying pressure on the interface. When the the shock is formed sufficiently close to the interface, this stage is considered to follow a previous initial phase controlled by the Ritchmyer-Meshkov instability that settles new initial conditions. The model reproduces the behavior of the instability observed in former numerical simulation results and provides a relatively simpler physical picture than the currently existing one for this stage of the instability evolution.

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