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1.
Environ Res ; 241: 117608, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37939804

RESUMO

Widespread saline soils in Northwest China pose a serious threat to the region's ability to use infrastructure safely because they are prone to soil structure damage when subjected to external environmental fluctuations, which in turn affects the stability of the foundations for buildings. The non-destructive approach of measuring resistivity can be used to swiftly reflect the subsoil body's state and make assumptions about its safety. However, the electrical resistivity of the underground soil body can be used to quickly identify unstable areas because the resistivity is influenced by the water content, salt content, and structural characteristics of the soil body. To do this, it is necessary to understand the coupling relationship between various factors. In this study, we first constructed samples with various water, salt, and soil structure characteristics, and then used indoor tests, such as soil resistivity measurement and thermogravimetric analysis, to analyze the multiple factors affecting the resistivity characteristics of the soil. The relationship between soil resistivity and actual saline soil diseases in Northwest China was then further discussed in conjunction with the results of the indoor tests and analyses. subsequently, the resistivity and soil properties have been measured in the field at specific locations in Northwest China where railway roadbeds are diseased. The study's findings can theoretically support a deeper comprehension of the law and mechanism of soil resistivity change, as well as provide assistance for building infrastructure in Northwest China.


Assuntos
Cloreto de Sódio , Solo , Solo/química , China , Água , Eletricidade
2.
Chemosphere ; 308(Pt 2): 136396, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36113648

RESUMO

Heavy metal pollution in urban soils and dust is mostly caused by extensive anthropogenic activity during urbanization and industrialization. In this research study, the pollution characteristics, sources, ecological and human health risks of heavy metals in urban soil, and dust have been thoroughly evaluated. The research findings demonstrate that dust has a higher level of contamination than urban soil, such as Pb, Cu, and Zn metals are more contaminated in both urban soil and dust throughout the city, and Hg and As are also found in locations with a high concentration of heavy industrial companies. This implies that traffic emissions are still a significant source of metals in urban areas, though industrial companies also contribute. The health risk assessment model used to calculate human exposure revealed that the non-carcinogenic and carcinogenic risks of selected metals in soil and dust were generally in the low range, except for the carcinogenic risk from Cr in children. Statistical analysis revealed that Cr and Ni concentrations were mainly of natural origin, Cu and Zn have been sourced from traffic, whereas Pb, Hg, and As have been sourced from industrial activities. The overall recommendation is that the road traffic environment and municipal construction facilities need to be improved to ensure the sustainable development of the city's environment, while pollution from industrial waste is strongly controlled.


Assuntos
Mercúrio , Metais Pesados , Poluentes do Solo , Criança , China , Cidades , Poeira/análise , Monitoramento Ambiental , Humanos , Desenvolvimento Industrial , Resíduos Industriais/análise , Chumbo/análise , Mercúrio/análise , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise , Urbanização
3.
Int J Biol Sci ; 17(15): 4365-4376, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803504

RESUMO

Given the heterogeneity of solid tumors, single-target CAR-T cell therapy often leads to recurrence, especially in ovarian cancer (OV). Here, we constructed a Tandem-CAR targeting two antigens with secretory activity (IL-12) to improve the effects of CAR-T cell therapy. Twenty coexpressed upregulated genes were identified from the GEO database, and we found FOLR1 (folate receptor 1) and MSLN (mesothelin) were specifically and highly expressed in cancer tissues and only 11.25% of samples were negative for both antigens. We observed an increased proliferation rate for these three CAR-T cells, and Tandem CAR-T cells could efficiently lyse antigen-positive OV cells in vitro and secrete higher levels of cytokines than single-target CAR-T cells. More importantly, in vivo experiments indicated that Tandem CAR-T cells markedly decreased tumor volume, exhibited enhanced antitumor activity, and prolonged mouse survival. Furthermore, the infiltration and persistence of T cells in the Tandem-CAR group were higher than those in the MSLN-CAR and Control-T groups but comparable to those in the FOLR1-CAR group. Collectively, this study demonstrated that Tandem CAR-T cells secreting IL-12 could enhance immunotherapeutic effects by reducing tumor antigen escape and increasing T cell functionality, which could be a promising therapeutic strategy for OV and other solid tumors.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Receptor 1 de Folato/metabolismo , Mesotelina/metabolismo , Neoplasias Ovarianas/terapia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Citocinas/genética , Citocinas/metabolismo , Bases de Dados Genéticas , Feminino , Receptor 1 de Folato/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-12/metabolismo , Mesotelina/genética , Camundongos , Camundongos Nus , Transcriptoma , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Int J Ophthalmol ; 13(4): 580-586, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32399408

RESUMO

AIM: To investigate the effects of intraocular lens (IOL) implantation on visual field (VF) in patients with glaucoma and comorbid cataracts (G&C) with different disease severities. METHODS: Totally 56 eyes of 50 patients with primary G&C were included. All patients were divided into three groups based on the severity of the VF defect: the mild, moderate, and severe stage. Phacoemulsification was performed for cataract removal combined with IOL implantation. Visual acuity (VA) and VF tests were performed for all enrolled patients, up to 3mo after surgery. Changes in VF threshold and global VF index in various groups were also recorded before and after surgery. The mean light sensitivity (MS) values and the changes following surgery (DMS) were compared between the three groups. Advanced Glaucoma Intervention Study (AGIS) scoring was analyzed on all VF results for analysis of changes in VF before and after surgery. RESULTS: Following surgery, the MS values of the three groups of G&C increased significantly, while the AGIS scores decreased statistically in all groups. The DMS values for the three zones in moderate and severe stage but not mild stage were statistically different between zones. The DMS value was significantly higher in zone I than those in zone II and III (zone I>zone II>zone III; P<0.05). The DMS was significantly higher in zone I than that in zone III in moderate stage patients (zone I>zone II>zone III; P<0.01), while the DMS values in the severe stage patients was significantly higher in zone I than those in zone II and III (zone I>zone II>zone III; P<0.01). CONCLUSION: The mean VF sensitivity of glaucoma patients increased significantly after cataract removal and IOL implantation. Variations in the severity and distribution of characteristics of VF defects result in differences in postoperative VF improvements after cataract surgery. The magnitude of increase in VF sensitivity is associated with VF defect characteristic in glaucoma.

5.
World J Stem Cells ; 12(3): 222-240, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32266053

RESUMO

BACKGROUND: Radiation induces rapid bone loss and enhances bone resorption and adipogenesis, leading to an increased risk of bone fracture. There is still a lack of effective preventive or therapeutic method for irradiation-induced bone injury. Receptor activator of nuclear factor κB ligand (RANKL) provides the crucial signal to induce osteoclast differentiation and plays an important role in bone resorption. However, the mechanisms of radiation-induced osteoporosis are not fully understood. AIM: To investigate the role of CR6-interacting factor-1 (Crif1) in osteoclastogenesis after radiation and its possible mechanism. METHODS: C57BL/6 mice were exposed to Co-60 gamma rays and received 5 Gy of whole-body sublethal irradiation at a rate of 0.69 Gy/min. For in vitro study, mouse bone marrow mesenchymal stem/stromal cells (BM-MSCs) were irradiated with Co-60 at a single dose of 9 Gy. For osteoclast induction, monocyte-macrophage RAW264.7 cells were cocultured with mouse BM-MSCs for 7 d. ClusPro and InterProSurf were used to investigate the interaction interface in Crif1 and protein kinase cyclic adenosine monophosphate (cAMP)-activited catalytic subunit alpha complex. Virtual screening using 462608 compounds from the Life Chemicals database around His120 of Crif1 was carried out using the program Autodock_vina. A tetrazolium salt (WST-8) assay was carried out to study the toxicity of compounds to different cells, including human BM-MSCs, mouse BM-MSCs, and Vero cells. RESULTS: Crif1 expression increased in bone marrow cells after radiation in mice. Overexpression of Crif1 in mouse BM-MSCs and radiation exposure could increase RANKL secretion and promote osteoclastogenesis in vitro. Deletion of Crif1 in BM-MSCs could reduce both adipogenesis and RANKL expression, resulting in the inhibition of osteoclastogenesis. Deletion of Crif1 in RAW264.7 cells did not affect the receptor activator of nuclear factor κB expression or osteoclast differentiation. Following treatment with protein kinase A (PKA) agonist (forskolin) and inhibitor (H-89) in mouse BM-MSCs, Crif1 induced RANKL secretion via the cAMP/PKA pathway. Moreover, we identified the Crif1-protein kinase cyclic adenosine monophosphate-activited catalytic subunit alpha interaction interface by in silico studies and shortlisted interface inhibitors through virtual screening on Crif1. Five compounds dramatically suppressed RANKL secretion and adipogenesis by inhibiting the cAMP/PKA pathway. CONCLUSION: Crif1 promotes RANKL expression via the cAMP/PKA pathway, which induces osteoclastogenesis by binding to receptor activator of nuclear factor κB on monocytes-macrophages in the mouse model. These results suggest a role for Crif1 in modulating osteoclastogenesis and provide insights into potential therapeutic strategies targeting the balance between osteogenesis and adipogenesis for radiation-induced bone injury.

6.
Plant Dis ; 104(3): 668-676, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31951509

RESUMO

Chili anthracnose caused by Colletotrichum spp. is an annual production concern for growers in China. Sterol C14-demethylation inhibitors (DMIs, such as tebuconazole) have been widely used to control this disease for more than three decades. In the current study, of 48 isolates collected from commercial chili farms in Jiangsu Province of China during 2018 and 2019, 8 single-spore isolates were identified as Colletotrichum gloeosporioides and the rest were identified as C. acutatum. To determine whether the DMI resistance of isolates develops in the field, mycelial growth of the 48 isolates was measured in culture medium with and without tebuconazole. In all, 6 of the 8 C. gloeosporioides isolates were resistant to tebuconazole, but all 40 of the C. acutatum isolates were sensitive to tebuconazole. The fitness cost of resistance was low based on a comparison of fitness parameters between the sensitive and resistant isolates of C. gloeosporioides. Positive cross-resistance was observed between tebuconazole and difenconazole or propiconazole, but not prochloraz. Alignment results of the CgCYP51 amino acid sequences from the sensitive and resistant isolates indicated that mutations can be divided into three genotypes. Genotype I possessed four substitutions (V18F, L58V, S175P, and P341A) at the CgCYP51A gene but no substitutions at CgCYP51B, while genotype II had five substitutions (L58V, S175P, A340S, T379A, and N476T) at CgCYP51A, concomitant with three substitutions (D121N, T132A, and F391Y) at CgCYP51B. In addition, genotype III contained two substitutions (L58V and S175P) at CgCYP51A, concomitant with one substitution (T262A) at CgCYP51B. Molecular docking models illustrated that the affinity of tebuconazole to the binding site of the CgCYP51 protein from the resistant isolates was decreased when compared with binding site affinity of the sensitive isolates. Our findings provide not only novel insights into understanding the resistance mechanism to DMIs, but also some important references for resistance management of C. gloeosporioides on chili.


Assuntos
Colletotrichum , Fungicidas Industriais , China , Simulação de Acoplamento Molecular , Mutação , Doenças das Plantas
7.
Zhongguo Zhong Yao Za Zhi ; 42(6): 1011-1014, 2017 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-29027409

RESUMO

Safety issues of traditional Chinese medicine injections has been heated debate. There are two diametrically opposed views: it should be used reasonable and developed healthily or be forbidden to use. Some people have many misunderstandings and prejudices about the safety of traditional Chinese medicine injections. Compared with western medicine,traditional Chinese medicine has its own particularity. Traditional Chinese medicine has complex components. Its research and clinical application is different from western medicine. Adverse reactions of traditional Chinese medicine injections are related to many factors,such as a large number of irrational use,blind use of traditional Chinese medicine injections and western medicine injections,counterfeit and substandard drugs,incorrect methods of intravenous infusion,toxicity of supplementary materials,drug ingredients. Developing traditional Chinese medicine injection is the need for curing sickness to save patients. The purposeful, targeted, organized and planned systematic research of traditional Chinese medicine injections should be strengthened,especially the safety of traditional Chinese medicine. Strengthen supervision and control of rational drug use.Strengthen the examination and approval,supervision and management of all aspects to ensure the safety of patients.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/normas , Medicina Tradicional Chinesa , Humanos , Injeções , Projetos de Pesquisa
8.
Medicine (Baltimore) ; 96(25): e7237, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28640122

RESUMO

This study reports the clinical emergency treatment of 68 critical patients with severe organophosphorus poisoning, and analyzes the prognosis after rescue.The general data of 68 patients with severe organophosphorus poisoning treated in our hospital were retrospectively analyzed. These patients were divided into 2 groups: treatment group, and control group. Patients in the control group received routine emergency treatment, while patients in the treatment group additionally received hemoperfusion plus hemodialysis on the basis of routine emergency treatment. The curative effects in these 2 groups and the prognosis after rescue were compared.Compared with the control group, atropinization time, recovery time of cholinesterase activity, recovery time of consciousness, extubation time, and length of hospital stay were shorter (P < .05); the total usage of atropine was significantly lower (P < .05); Glasgow Coma Score was significantly higher (P < .05); acute physiology and chronic health score (APACHE II) was significantly lower (P < .05); and mortality and poisoning rebound rate was significantly lower (P < .05) in the treatment group.Hemoperfusion and hemodialysis on the basis of routine emergency treatment for critical patients with organophosphorus poisoning can improve rescue outcomes and improve the prognosis of patients, which should be popularized.


Assuntos
Tratamento de Emergência , Hemoperfusão , Intoxicação por Organofosfatos/terapia , Diálise Renal , APACHE , Adulto , Idoso , Tratamento de Emergência/efeitos adversos , Feminino , Escala de Coma de Glasgow , Hemoperfusão/efeitos adversos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Intoxicação por Organofosfatos/complicações , Intoxicação por Organofosfatos/diagnóstico , Intoxicação por Organofosfatos/mortalidade , Prognóstico , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
J Asian Nat Prod Res ; 17(5): 475-81, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26023740

RESUMO

A new diterpenoid, dehydrovibsanin G (1), a new lignan, (+)-9'-O-senecioyllariciresinol (2), and six known compounds (3-8) were isolated from the branches and leaves of Viburnum odoratissimum var. odoratissimum. The structures of these compounds were elucidated by analysis of spectroscopic data. Both new compounds showed moderate inhibitory activity against human A431 and T47D tumor cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Diterpenos/isolamento & purificação , Lignanas/isolamento & purificação , Viburnum/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Diterpenos/química , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Folhas de Planta/química
10.
Zhongguo Zhong Yao Za Zhi ; 39(1): 3-4, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24754158

RESUMO

Clinical re-evaluation is to verify the drug's safety and effectiveness again,while the drug itself has not been improved. However, due to the complexity of traditional Chinese medicine, ingredients in bulk drugs, prescription, productive processes, quality standards and other aspects need to be enhanced. So improving the quality, safety and effectiveness of traditional Chinese medicine by clinical re-evaluation is also very necessary. Therefore, except for achieving those basic requirements of medicine, it should also be improved on itself and pay full attention to the particularity, then traditional Chinese medicine's clinical re-evaluation will play its due role.


Assuntos
Medicamentos de Ervas Chinesas/normas , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/normas , Segurança/normas , Prescrições de Medicamentos/normas , Humanos , Controle de Qualidade
11.
J Comp Physiol B ; 184(3): 329-46, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24469919

RESUMO

Many animals experience fasting because of the high temporal and spatial sporadicity of food availability. Once food is available, animals use external energy to restore their depressed functional performance. In the present study, the physiological and morphological responses to the first bout of refeeding in juvenile southern catfish (Silurus meridionalis) were characterized. Fish that had undergone long-term fasting (fasted for 32 days, the S32 group) exhibited a lower resting metabolic rate (MO(2rest) decreased by 49%), lower peak metabolic rate (MO(2peak) decreased by 24%), greater energy expenditure (increased by 15%) during specific dynamic action (SDA) and longer duration SDA response (increased by 41%) than those of a control group (S0 group, fasted for 0 days). The S32 group showed a significantly reduced peak gastric evacuation rate (0.131 g meal h(-1)) compared with the S0 group (0.315 g meal h(-1)). The S0 group also had a shorter gastric evacuation time (36 h) than either of the two fasting groups (both 64 h). The S32 group displayed a higher minimum gastric pH (3.1) than the S0 and S16 groups (2.6). Refeeding did not trigger an increase in the wet mass of the gastrointestinal tract, whereas the liver wet mass of the S0 and the two fasting groups increased significantly with refeeding. The trypsin and lipase of the S0 group showed higher mass-specific activities and organ capacities than either of the two fasting groups at certain specific time points. A similar result was found for aminopeptidase activity. Multiple loach meals equaling 6% of the body weight of the fed fish completely restored the liver morphology within the S16 but not the S32 group. Our results suggest that the regulation of the digestive performance of the gastrointestinal tract in S. meridionalis that are finishing their first small meal after fasting is delayed compared with that of nonfasting fish and that it is similar to the characteristics (lower MO(2peak), greater SDA and a longer duration of the SDA response) of the refeeding SDA.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Peixes-Gato/fisiologia , Trato Gastrointestinal/fisiologia , Aminopeptidases/metabolismo , Animais , Metabolismo Basal , Peso Corporal/fisiologia , Metabolismo Energético/fisiologia , Jejum , Trato Gastrointestinal/metabolismo , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Fígado/fisiologia , Microvilosidades/fisiologia , Oxigênio/metabolismo , Período Pós-Prandial/fisiologia , Tripsina/metabolismo
12.
Tumour Biol ; 35(4): 3905-15, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24347488

RESUMO

Numerous epidemiological studies have been conducted to investigate the association between Xeroderma pigmentosum complementation group D (XPD) Asp312Asn (rs1799793 G > A) and Lys751Gln (rs13181 A > C) polymorphisms and bladder cancer risk; however, the conclusions remain controversial. With this in mind, we performed this meta-analysis with 11 studies including 3,797 cases and 5,094 controls for Asp312Asn and 21 studies including 6,360 cases and 7,894 controls for Lys751Gln polymorphism. We searched available literatures from PubMed, Embase, and CBM databases. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the strength of the associations. Moreover, to validate biological plausibility of our findings, the effects of these two polymorphisms on XPD gene expression within three ethnicities was determine by gene expression analysis based on imputed genotypes from HapMap. Overall, the variant allele of Asp312Asn polymorphism was associated with an increased risk of bladder cancer (Asn/Asn vs. Asp/Asp: OR = 1.51, 95% CI = 1.19-1.91; Asp/Asn vs. Asp/Asp: OR = 1.23, 95% CI = 1.12-1.35; recessive model: OR = 1.33, 95% CI = 1.10-1.61; dominant model: OR = 1.32, 95% CI = 1.14-1.52; and allele comparing: OR = 1.26, 95% CI = 1.11-1.42). We found the Lys751Gln was associated with increased bladder cancer risk only under the recessive model (OR = 1.14, 95% CI = 1.01-1.29). Stratification analyses demonstrated an increased risk for Asians and hospital-based studies under all genetic models while only under the dominant model for Caucasians as to the Asp312Asn polymorphism and for Caucasians under the recessive model as to the Lys751Gln polymorphism. We also found the Asp312Asn polymorphism can significantly influence mRNA expression levels among Asians and Caucasians, and the Lys751Gln polymorphism has a similar effect for Caucasians. Despite some limitations, this meta-analysis suggests that polymorphisms in XPD gene may contribute to bladder cancer susceptibility. These findings need further validation by large well-designed prospective studies.


Assuntos
Predisposição Genética para Doença , Polimorfismo Genético , Neoplasias da Bexiga Urinária/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética , Humanos , Viés de Publicação , Risco , Neoplasias da Bexiga Urinária/etiologia
13.
Zhongguo Zhong Yao Za Zhi ; 38(12): 2001-4, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-24066600

RESUMO

OBJECTIVE: To compare the acute myocardial infarction models in Beagle dogs and mongrel dogs, and study whether the Beagle dog model is sensitive to drug intervention. METHOD: The acute myocardial infarction model of dog was set up through ligation of anterior descending branch of coronary artery in dogs, in order to observe morphological changes of the heart and determine artery length and heart coefficient of exposed anterior descending branch of coronary artery. The epicardium electrocardiogram (sigmaST, N-ST) was used to measure the degree of myocardial ischemia. The quantitative histological assay (nitroblue tetrazolium, N-BT stain) was adopted to determine the area of myocardial infarction. RESULT: There was no significant difference between Beagle dogs and mongrel dogs in terms of sigmaST, N-ST and ischemia area. The diltiazem group of Beagle dogs showed obvious reduction in the ischemia area (P < 0.05 and P < 0.01), with notable decline in sigmaST and N-ST, however, it had no statistical difference compared with the Beagle dog model group. Beagle dogs had clear coronary branches, longer exposed arteries and less difference in organ coefficient, which were suitable for the preparation of the myocardial infarction model, whereas mongrel dogs had irregular coronary branches and exposed arteries, with greater individual difference. CONCLUSION: Beagle dogs are superior to mongrel dogs in the preparation of the acute myocardial infarction model, which is sensitive to for drug intervention.


Assuntos
Modelos Animais de Doenças , Infarto do Miocárdio/patologia , Doença Aguda , Animais , Cães , Eletrocardiografia , Feminino , Masculino , Infarto do Miocárdio/tratamento farmacológico , Miocárdio/patologia
14.
Fish Physiol Biochem ; 38(5): 1459-75, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22466311

RESUMO

Postprandial physiological and morphological responses to feeding were examined in juvenile southern catfish (Silurus meridionalis Chen) that had consumed a loach (Misgurnus anguillicaudatus Cantor) meal equivalent to 6 % of the body mass of the catfish. The gastric evacuation rate (GER) peaked at 4 h postfeeding, averaging 0.36 g food weight h(-1), at which time 14 % of the ingested meal had passed into the intestine. Less than 10 % of the ingested meal remained in the stomach at 24 h postfeeding. Pepsin activity peaked at 8 h postfeeding, reaching a level approximately twofold higher than the prefeeding level. Pancreatic trypsin activity peaked at 16 h postfeeding, reaching a level 4.5-fold higher than the prefeeding level. Peaks in lipase activity in both the proximal and middle intestinal segments occurred at 16 h, reaching 2.8- and 2.4-fold higher levels than the prefeeding level, respectively, while the activity in the distal intestine segment reached a level 2.9-fold higher than the prefeeding level at 24 h postfeeding. With respect to amylase activity, only the middle intestinal segment exhibited a change, first an increase and then a decrease, after feeding. Feeding also triggered an approximately 200 % increase in the metabolic rate and resulted in 44.6 kJ kg(-1) being expended on specific dynamic action, equivalent to 16.1 % of the meal's energy. In terms of organ size, the wet mass of the liver increased by 11 % at 24 h postfeeding, whereas the wet mass of the pancreas did not change. Except for a decrease in the thickness of the submucosa in the middle intestinal segment, the thickness of the intestinal fold, mucosa, submucosa, muscularis and serosa of each intestinal segment did not change significantly with feeding. These results suggest that the continuum of physiological responses observed with respect to metabolic increases, GER, regulation of pancreatic and intestinal digestive enzyme activities and liver wet mass to feeding corresponds to the changes in the demand on the digestive system in S. meridionalis. Moreover, species maintained stable gastrointestinal tract morphology during the short interval of repeated feeding.


Assuntos
Peixes-Gato/fisiologia , Ingestão de Alimentos/fisiologia , Trato Gastrointestinal/anatomia & histologia , Trato Gastrointestinal/fisiologia , Animais , Metabolismo Energético , Trato Gastrointestinal/enzimologia , Período Pós-Prandial
15.
Artigo em Inglês | MEDLINE | ID: mdl-22405802

RESUMO

The size and functional capacity of the gastrointestinal (GI) tract and associated organs vary in response to environmental cues. The GI tract and associated organs are also very metabolically active in animals. Hence, animals may reduce the size and function of their GI tract to conserve energy when deprived of food. The main aims of this study were to investigate how Silurus meridionalis regulates the function and structure of its GI tract and associated organs during starvation. Starvation induced a decrease in both maintenance metabolism (MO(2rest), decreased by approximately 50%) and respiratory frequency (indicated by double side gill activity and notated as f(R), decreased by 29%). Lipase, trypsin and aminopeptidase-A showed a similar reduction in mass-specific activities during starvation, but pepsin and α-amylase did not. The starvation of experimental fish resulted in a significant reduction in body weight, the wet mass of the liver and the digestive-somatic system, the hepato-somatic index and the condition factor whereas the wet masses of the GI tract, pancreas, gall bladder and the relative intestinal length did not vary significantly during starvation. The reduction in liver wet mass was the main reason for the decrease in the wet mass of digestive-somatic system in this species. Only the mucosal area of the PI was affected significantly by starvation, decreasing by 34% at the end of the experiment. S. meridionalis displayed a decreasing intestinal mucosal area towards the distal intestine, and this gradient was not affected by starvation. The morphology and structure of both the GI tract and the liver were greatly down-regulated, as indicated by decreases in liver cell size, the mucosal thickness of the stomach and intestine, the density of goblet cells and microvilli surface area (MVSA), implying that food deprivation greatly impaired the digestive and absorptive functions of the GI tract in S. meridionalis. When deprived of food, S. meridionalis can endure harsh periods of starvation and adaptively down-regulate the function and structure of the digestive tract with physiological and biochemical strategies.


Assuntos
Peixes-Gato/fisiologia , Sistema Digestório/fisiopatologia , Trato Gastrointestinal/fisiologia , Inanição/fisiopatologia , Animais , Peso Corporal/fisiologia , Peixes-Gato/metabolismo , Sistema Digestório/enzimologia , Sistema Digestório/metabolismo , Regulação para Baixo/fisiologia , Feminino , Trato Gastrointestinal/enzimologia , Trato Gastrointestinal/metabolismo , Glutamil Aminopeptidase/metabolismo , Mucosa Intestinal/enzimologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiologia , Lipase/metabolismo , Microvilosidades/enzimologia , Microvilosidades/metabolismo , Microvilosidades/fisiologia , Tamanho do Órgão/fisiologia , Inanição/metabolismo , Tripsina/metabolismo , alfa-Amilases/metabolismo
16.
Zhonghua Wai Ke Za Zhi ; 42(16): 965-7, 2004 Aug 22.
Artigo em Chinês | MEDLINE | ID: mdl-15363230

RESUMO

OBJECTIVE: To explore the clinical application of Intra-aortic balloon pump (IABP) and centrifugal pump in low cardiac output syndrome (LCOS) after coronary artery bypass grafting (CABG). METHODS: From April 2000 to January 2004, 5 patients suffered serious LCOS after CABG in our department. Because maximum vasoactive agent had no significant effect, we supported these 5 patients with IABP and centrifugal pumps. The centrifugal pumps were connected with cannulas of right superior pulmonary vein and ascending aorta. The flow rate of the centrifugal pumps were increased to 3-4 L/min gradually. The dosage of vasoactive agent and flow rate of the centrifugal pumps were decreased gradually after hemodynamics stabilized. RESULTS: All 5 patients' hemodynamics were improved significantly after the left ventricular assist by IABP and centrifugal pumps. Five patients were weaned from the centrifugal pumps after 4 to 7 days successfully. But some degree damage to blood cells and renal function were detected. Renal function of 3 patients were recovered gradually after centrifugal pumps removed and discharged successfully, One patient died of acute renal failure, 1 patient died of multiple organ failure, 5 patients need transfusion of whole blood or concentrated erythrocytes and 4 patients need transfusion of platelets. CONCLUSIONS: There were significant improvements in hemodynamics after support with IABP and centrifugal pumps in the patients who suffered serious LCOS with less effect of maximum vasoactive agent after CABG. Some complications on blood cells and renal function should be paid more attention.


Assuntos
Baixo Débito Cardíaco/cirurgia , Ponte de Artéria Coronária/efeitos adversos , Coração Auxiliar , Balão Intra-Aórtico , Idoso , Baixo Débito Cardíaco/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
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