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1.
Article | IMSEAR | ID: sea-219412

ABSTRACT

Recognition and responsiveness to food taste becomes a crucial event in foraging and feeding behaviour of an organism. Adjusting the feeding behaviour through a sophisticated and robust taste system is critical to fulfil their nutritional needs and facilitate its survival in environment. Palatability of food sources depends on the sensory and motor cues provided by the brain, in co-ordination with the other body systems to enable decisive feeding. Drosophila melanogaster is an apt model organism to decipher these behavioural paradigms. Octopamine a neurotransmitter, is required in regulation of feeding behavioural responses. olf413, a paralogue of TH, is a gene predicted for its involvement in octopamine biosynthesis. The biological function of this gene is yet to be unravelled. Here we propose this gene function in taste recognition, food preference and feeding activity. We test the olf413 loss of function mutants for food preference between two fruit extracts using CAFE and horizontal box methods. In our study we have used olf413 gene disruption strain, olf413MI02014 homozygous and in transheterozygous condition with another allele isolated in our lab, olf413SG1.1. The results show that olf413 mutants display a severe phenotype in feeding behaviour and there is an allele specific phenotypic distinction between the two strains. Thus implying that olf413 gene function is required for taste recognition, starvation driven initiation and execution of feeding behaviour of the flies.

2.
Journal of China Pharmaceutical University ; (6): 392-399, 2022.
Article in Chinese | WPRIM | ID: wpr-939964

ABSTRACT

@#Starvation therapy is an emerging oncological treatment that targets the abnormally elevated nutrient uptake and metabolic pathways to inhibit and kill tumors. In addition to glucose, the targets of starvation therapy also include other nutrients in tumor cells.However, concerns like ineffective targeting and drug tolerance probably have an impact on their clinical translation.Nanomaterial-assisted starvation treatment has been developing quickly in recent years to address these concerns.In this review, several exemplary nanomedicines for starvation therapy and combined starvation therapy with other therapies were offered.They target nutrients other than glucose metabolism, including lactic acid, amino acids, and lipids, using nanomaterials to improve the efficacy of starvation therapy.This review provides reference for further development of nanomedicines with starvation treatment effect.

3.
Braz. j. biol ; 80(1): 73-80, Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1089279

ABSTRACT

Abstract Stresses can be caused by multiple biotic and abiotic factors and their effects can affect both the biology and the immune system of insects. American cockroach - Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae) -besides being an excellent model species, has great medical importance because it can act as a mechanical vector of several pathogens. This study aimed to evaluate the influence of starvation, dehydration and both stresses on weight, and total and differential haemocyte count in P. americana adults. Each specimen was isolated in glass flasks containing or not food and/or water. They were weighed periodically. Another group received water for 24 h after the end of stress period. In the immunologic bioassay, we counted their haemocytes after the final weighing. All stresses reduced the insect weight, especially when the stresses were combined. Females of the control group gained weight and males had it unaltered. Different stress conditions and time did not influence on total haemocyte count. Insects without food and water had the proportion of prohaemocytes increased and plasmatocytes decreased. This study can serve as a basis of further studies of bioecology, behaviour and the ability of resisting insecticides, besides serving as a model to studies in other insect species.


Resumo Os estresses podem ser causados por múltiplos fatores bióticos e abióticos e seus efeitos podem afetar tanto a biologia como o sistema imune dos insetos. A barata-americana - Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae) - além de ser uma excelente espécie modelo, tem grande importância médica, pois pode atuar como vetor mecânico de diversos patógenos. O objetivo desse estudo foi avaliar a influência da inanição, desidratação e ambos os estresses sobre o peso e o número total e diferencial de hemócitos em adultos de P. americana. Cada espécime foi isolado em frascos de vidro contendo ou não alimento e/ou água. Eles foram pesados periodicamente. Outro grupo recebeu água por 24 h após o término do período de estresse. Nos ensaios imunológicos, foram contados os seus hemócitos após a última pesagem. Todos os estresses reduziram o peso dos insetos, especialmente quando os estresses foram combinados. As fêmeas do grupo controle ganharam peso e os machos tiveram seu peso inalterado. As diferentes condições de estresse e tempo não influenciaram no número total de hemócitos. Os insetos sem alimento e água tiveram a proporção de pró-hemócitos aumentada e a de plasmatócitos reduzida. Esse estudo pode servir como base para estudos posteriores de bioecologia, comportamento e da habilidade de resistir aos inseticidas químicos, além de servir como modelo para estudos em outras espécies de insetos.


Subject(s)
Animals , Male , Female , Periplaneta , Cockroaches , Insecticides , Diet , Immune System
4.
Clin. biomed. res ; 40(4): 242-246, 2020. tab, ilus
Article in Portuguese | LILACS | ID: biblio-1252765

ABSTRACT

Encefalopatia de Wernicke (EW) e síndrome de realimentação (SR) são duas condições frequentemente coexistentes, subdiagnosticadas e que podem implicar prognóstico reservado após sua instalação. Sua identificação precoce representa um desafio para os intensivistas, haja vista a falta de sensibilidade e especificidade das manifestações clínicas. Apresenta-se um relato de caso de uma paciente portadora de esquizofrenia paranoide, sem histórico de abuso de álcool, que desenvolveu quadro de coma irreversível após greve de fome, sendo feito diagnóstico tardio de EW associada a SR. Descreve-se a evolução clínica e neuropsiquiátrica com o intuito de enfatizar a necessidade crucial de alta suspeição diagnóstica, com reposição vitamínica imediata, vigilância de distúrbios eletrolíticos e progressão parcimoniosa do aporte nutricional. (AU)


Wernicke encephalopathy (WE) and refeeding syndrome (RFS) are two often coexisting, underdiagnosed conditions that may involve a poor prognosis after their onset. Early identification represents a challenge for intensivists, given the lack of sensitivity and specificity of clinical manifestations. We report a case of a patient with paranoid schizophrenia, without a history of alcohol abuse, who developed irreversible coma after a hunger strike, with a late diagnosis of WE associated with RFS. The clinical and neuropsychiatric outcomes are described herein in order to emphasize the crucial need for a high diagnostic suspicion, with immediate vitamin replacement, monitoring of electrolyte disorders, and gradual progression of nutritional support. (AU)


Subject(s)
Humans , Female , Middle Aged , Wernicke Encephalopathy/diagnosis , Coma/etiology , Refeeding Syndrome/diagnosis , Starvation/complications , Delayed Diagnosis
5.
Tumor ; (12): 146-152, 2020.
Article in Chinese | WPRIM | ID: wpr-848213

ABSTRACT

Glucose oxidase is a kind of endogenous oxidoreductase which exi sts wi del y i n organi sm. I n recent years, due to i ts i nherent biocompatibility, low toxicity and unique catalytic effect on betaD-glucose, glucose oxidase has attracted more and more attention in the field of biomedicine. Glucose oxidase can effectively catalyze the oxidation of glucose into gluconic acid and hydrogen peroxide. Researchers have developed various anticancer therapies based on gl ucose oxi dase usi ng t hi s cat al yt i c propert y: (1) gl ucose consumption provides alternative treatment strategies for cancer starvation; (2) oxygen consumption increases tumor hypoxia, which can be used for tumor hypoxia activation therapy; (3) the production of gluconic acid increases the acidity of tumor microenvironment, which can trigger the release of pH-responsive drugs; (4) the production of hydrogen peroxide increases the oxidative stress level of tumors. Hydrogen peroxide can be converted into toxic hydroxyl radicals by being exposed to light (such as near-infrared light) or fenton reaction, thus killing cancer cells. In addition, glucose oxidase can also be used in combination with other biological enzymes, hypoxia-activated prodrugs, photosensitizers or fenton reagents to produce the multi-mode synergistic anticancer therapies with starvation therapy as the main part, cooperating with hypoxia-activated therapy, oxidation therapy, photodynamic therapy and light therapy, etc. In this review, the glucose oxidase-mediated tumor monotherapy is firstly introduced, and the multi-mode synergistic anti-cancer therapy mediated by glucose oxidase as well as its specific anti-tumor mechanism are systematically elaborated.

6.
Braz. j. biol ; 79(2): 165-168, Apr.-June 2019. tab
Article in English | LILACS | ID: biblio-989437

ABSTRACT

Abstract Neotropical nectar-feeding bats consume large amounts of sugar and use most of their energy-rich diet directly from the bloodstream, suggesting an adaptation towards lower body energy reserves. Here we tested the hypothesis that bats Glossophaga soricina spare the energy costs of storing energy reserves, even if this would represent a risky susceptibility during fasting. Blood glucose concentrations in 18 h fasted bats showed a 40% decrease. Breast muscle and adipose tissue lipids, as well as carcass fatty acids and liver glycogen, were also decreased following fasting. The inability to keep normoglycemia following a short-term fasting (i.e. 28 h) confirm that nectar bats invest little on storing energy reserves and show a severe fasting susceptibility associated to this pattern. Our study also support the general hypothesis that evolutionary specializations towards nectar diets involve adaptations to allow a decreased body mass, which reduces the energy costs of flight while increases foraging time.


Resumo Morcegos nectarívoros que ocorrem na região Neotropical consomem grandes quantidades de carboidratos, e usam a energia obtida da dieta diretamente, a partir da glicose na circulação sanguínea. Esta adaptação sugere que morcegos nectarívoros tenham evoluído no sentido de apresentar adaptações fisiológicas que permitam o baixo armazenamento de reservas energéticas corporais. Nós testamos a hipótese de que morcegos Glossophaga soricina poupam o gasto energético envolvido com a formação de reservas energéticas teciduais, mesmo que isso represente uma arriscada suscetibilidade da espécie frente ao jejum. As concentrações de glicose apresentaram uma diminuição de 40% após 18 h de jejum. As concentrações de lipídios do músculo peitoral e do tecido adiposo, bem como as de ácidos graxos da carcaça e glicogênio hepático também diminuíram após 18 h de jejum. A incapacidade de manter a normoglicemia observada após o jejum de curto-prazo confirma que morcegos nectarívoros desta espécie não investem na formação de reservas energéticas, e apresentam, consequentemente, uma severa susceptibilidade ao jejum. Este estudo suporta a hipótese de que adaptações evolucionárias da espécie envolvem diminuição da massa corporal, reduzindo o custo energético do voo e aumentado o tempo de forrageamento.


Subject(s)
Animals , Chiroptera/physiology , Fasting/physiology , Energy Metabolism/physiology , Plant Nectar/metabolism , Blood Glucose/physiology , Adipose Tissue/metabolism , Adipose Tissue/chemistry , Muscle, Skeletal/metabolism , Muscle, Skeletal/chemistry , Feeding Behavior
7.
Article | IMSEAR | ID: sea-209531

ABSTRACT

Starvation is a global challenge. Nutritional status of an organism may influence its psychosocial behavior and other nervous system processes like motor responses and its ability to learn and memorize. This study determined the impact of starvation-induced stress on memory sensitization, habituation and psychosomatic responses in an experimental animal design. 25 wistar rats were randomly sampled and grouped into 1-control, 2-feed after 6 hours deprivation, 3-feed after12 hours deprivation, 4-feed after 18 hours deprivation and 5-feed after 24 hours deprivation. Behavioral tests carried out included the multiple maze tests and elevated plus maze test. Grip strength test was performed to determine neuromuscular response and endurance in all groups. Biochemical investigation of brain stress markers was done on the last day of the study. There was a significant (P≤0.05) enhancement in memory processes and anxiolytic behavior after 6 hours feed deprivation. An increase in antioxidants after 6 hours feed deprivation was suspected to be a compensatory response. A progressive decrease in memory facilitation, anxiolytic behavior and muscular strength was reported after 12, 18 and 24 hours feed deprivation. The increase in habituation and decrease in psychosomatic response was observed and appreciated as the duration of feed deprivation was increased. This study provided evidence about a possible link between memory processes and stress-related alterations in calcium, magnesium and nitric oxide. Starvation may impairlearning, memory and motor responses, but this tendency is dependent on the extent of feed deprivation and nutrient depletion.

8.
J Biosci ; 2019 Mar; 44(1): 1-15
Article | IMSEAR | ID: sea-214195

ABSTRACT

DNA methylation is an important epigenetic modification that governs transcriptional regulation. The methylation mark isread by a special class of proteins called methyl-CpG-binding domain proteins. The role of DNA methylation has beenfound in X-chromosome inactivation, genomic imprinting, transposon silencing, and self-incompatibility. Recently,remodeling of global DNA methylation was demonstrated in Arabidopsis during low phosphate availability. The presentstudy reports that AtMBD4 gene of Arabidopsis negatively regulates phosphate starvation. The T-DNA insertion mutation atthe AtMBD4 locus exhibited altered root architecture as compared to wild-type plants. Using microarray hybridization andanalysis, an increased transcript accumulation of 242 genes was observed in the mutant. Many of these genes were relatedto phosphate transporters and transcription factors, involved in phosphate starvation response. Comparison of data ofatmbd4 mutant with publicly available microarray data of phosphate starvation response indicated the role of AtMBD4protein in phosphate starvation response. Further, promoter analysis of up-regulated genes suggested that cis-regulatoryelements like MBS, W-box, and B1BS are more prominent in the promoters of up-regulated genes. Upon performing amethylation-specific PCR, a decreased DNA methylation in the promoter regions of up-regulated genes was observed. Theaccumulation of anthocyanin and inorganic phosphate in the atmbd4 mutant was found to be higher than the wild-typeplant. Altered root morphology, up-regulation of phosphate starvation-induced genes in atmbd4 mutant suggests thatAtMBD4 negatively regulates the phosphate starvation response.

9.
Rev. Soc. Bras. Med. Trop ; 52: e20180001, 2019. tab, graf
Article in English | LILACS | ID: biblio-1041589

ABSTRACT

Abstract INTRODUCTION: Studies have demonstrated that pathogens react to the harsh conditions in human tissues by inducing mechanisms that promote survival. METHODS: Persistence and biofilm-forming ability were evaluated during stress conditions that mimic those in the host. RESULTS: Carbon-source availability had a positive effect on Staphylococcus epidermidis RP62A adhesion during hypoxia, accompanied by a decrease in pH. In contrast, iron limitation led to decreased surface-adherent biomass, accompanied by an increase medium acidification and lactate levels. Interestingly, iron starvation and hypoxia induced persister cells in planktonic culture. CONCLUSIONS: These findings highlight the role of host stress in the virulence of S. epidermidis.


Subject(s)
Humans , Staphylococcus epidermidis/physiology , Virulence/physiology , Biofilms/growth & development , Culture Media/pharmacology , Host Microbial Interactions/physiology , Staphylococcus epidermidis/drug effects , Staphylococcus epidermidis/pathogenicity , Stress, Physiological , Virulence/drug effects , Biological Assay , Host Microbial Interactions/drug effects
10.
Acupuncture Research ; (6): 799-804, 2019.
Article in Chinese | WPRIM | ID: wpr-844231

ABSTRACT

OBJECTIVE: To explore the effect of electroacupuncture (EA) serum on expression of myogenic differentiation antigen (Myod) and autophagy-related protein Beclin 1 in cultured muscle satellite cells of rats under starvation conditions. METHODS: The primary multifidus muscle satellite cells of one male SD rat were isolated and cultured to obtain the 3rd generation of cells. The EA serum was got from the rat received EA stimulation of bilateral "Weizhong" (BL40, 2 Hz/10 Hz, 1 mA, duration of 20 min, once daily for 7 days). The cell suspension (2×104/well) of the 3rd generation of cultured cells was transferred to each well of a 96-well plate in medium containing 10% fetal bovine serum (FBS). Twelve duplicate wells were set up for the blank control serum (without FBS), 10% FBS, 10% EA serum, 20% EA serum and 30% EA serum groups and incubated for 12 h and 24 h, respectively. Each well was supplemented with 10 µL CCK-8 reagent to be incubated for 1 h again for observing the state of cell proliferation. After culturing the primary muscle satellite cells in serum-free medium for 12 h, the cells were randomly divided into serum-free group, 10% fetal bovine serum group and optimal concentration electroacupuncture serum group, and serum of corresponding concentration was added respectively. The expression levels of Beclin 1 and cell-proliferation-related protein Myod were detected by Western blot. RESULTS: CCK-8 assay displayed that the proliferation levels were significantly higher at 12 h and 24 h after serum intervention in the 10% FBS, 10% EA serum, 20% EA serum and 30% EA serum groups than that in the blank control serum group (P0.05). As a result, 10% EA serum was selected as the optimal concentration for Western blot tests. No significant difference was found in the expression levels of Myod and Beclin 1 proteins among the serum-free, 10% FBS and 10% EA serum groups before intervention (P>0.05), and there was a marked up-regulation of Myod expression and an obvious down-regulation of Beclin 1 expression at 12 h in both the 10% EA serum and 10% FBS groups in comparison with their own pre-intervention (P0.05). CONCLUSION: EA serum can promote proliferation of cultured muscle satellite cells under starvation conditions, which is related to its functions in regulating expression of Beclin 1 and cell-proliferation-related protein Myod.

11.
Chinese Pharmacological Bulletin ; (12): 958-961, 2019.
Article in Chinese | WPRIM | ID: wpr-857203

ABSTRACT

Aim To research the cross-talk and conversion between macroautophagy and chaperone-media-ted autophagy ( CMA) in cultured Burkitt lymphoma Raji cells induced by starvation. Methods The autophagic vacuoles were observed by fluorescence microscopy and confocal laser-scanning microscopy with monodansylcadaverine staining. The expression of autophagy associated-proteins were determined by West-em blot. Results Both macroautophagy and CMA were activated sequentially instead of simultaneously in starvation-induced Raji cells, and macroautophagy was quickly activated and peaked during the first hours of near baseline. With starvation persisted, CM A progressively increased along with the decline of macroautoph- A gy. Conclusions Macroautophagy and CMA are maximally activated during different stages of starvation. Activation of these two pathways is often sequential. The sequential switch from macroautophagy to CMA might be conducive to the adaption of cancer cells to miscellaneous intracellular or extracellular changes, maintaining their own growth and proliferation.

12.
Biosci. j. (Online) ; 34(4): 1033-1040, july/aug. 2018. ilus, tab
Article in English | LILACS | ID: biblio-967264

ABSTRACT

There is few information about troponin gene expression by starvation in insect skeletal muscle and digestive tracts. The objective of this study was to perform molecular cloning of troponin I from the two-spotted cricket, Gryllus bimaculatus (GrybiTnI) and determine its expression patterns in three different skeletal muscles and digestive tracts during starvation. GrybiTnI was translated into a protein encoding 198 amino acids with a theoretical isoelectric point of 9.78 and a molecular weight of 23671.46 Da. The GrybiTnI has both the TnC-binding site and actin/TnC-binding site shown in the typical TnI amino acid sequences. Homology analysis revealed that GrybiTnI exhibited high similarity at the amino acid level to those of other insects already reported; 89~77% identity with those of other insects. Expression of GrybiTnI by starvation did not change in dorsal wing flight muscle and dorsal ventral flight muscle, but showed up-expression in dorsal longitudinal flight muscle. In the digestive tracts, the up-expression of GrybiTnI by starvation was observed only in the hindgut but not in the rest parts including Malpighian tubules. Re-feeding following starvation restored those expressions about the level before starvation in the dorsal longitudinal flight muscle and hindgut. In conclusion, troponin modulates gene expression not only to muscle elements but also to physiological changes such as strains.


Existe pouca informação sobre a expressão gênica da troponina por inanição no músculo esquelético de insetos e no trato digestório. O objetivo deste estudo foi realizar clonagem molecular da troponina I do grilo africano, Gryllus bimaculatus (GrybiTnI) e determinar seus padrões de expressão em três diferentes músculos esqueléticos e tratos digestivos durante a inanição. GrybiTnI foi traduzido em uma proteína codificando 198 aminoácidos com um ponto isoelétrico teórico de 9,78 e um peso molecular de 23671,46 Da. O GrybiTnI tem o local de ligação a TnC e o local de ligação a actina/TnC mostrado nas sequências de aminoácidos TnI típicas. A análise de homologia revelou que GrybiTnI exibiu alta similaridade no nível de aminoácidos em relação àqueles de outros insetos já relatados; 89~77% de identidade com os de outros insetos. A expressão de GrybiTnI pela inanição não se alterou no músculo de vôo da asa dorsal e no músculo de vôo ventral dorsal, mas mostrou expressão positiva no músculo de vôo longitudinal dorsal. Nos tratos digestivos, a expressão positiva de GrybiTnI por inanição foi observada apenas no intestino grosso, mas não nas partes de repouso, incluindo os túbulos de Malpighi. A realimentação após a inanição restaurou as expressões aproximadamente ao nível antes da inanição no músculo de vôo longitudinal dorsal e no intestino grosso. Em conclusão, a troponina modula a expressão gênica não apenas em elementos musculares, mas também em alterações fisiológicas, como as cepas.


Subject(s)
Starvation , Troponin , Gryllidae , Cloning, Molecular , Gene Expression , Muscle, Skeletal , Gastrointestinal Tract
13.
Chinese Journal of Hepatology ; (12): 42-47, 2018.
Article in Chinese | WPRIM | ID: wpr-805970

ABSTRACT

Objective@#To investigate the role of short-term starvation (STS) in alleviating hepatic ischemia-reperfusion injury in mice and possible mechanism of action.@*Methods@#Wild-type male C57BL/6 mice aged 8 weeks were randomly divided into 75% hepatic ischemia-reperfusion injury group (IR group), STS+75% hepatic ischemia-reperfusion injury group (STS group), and sirtinol+STS+75% hepatic ischemia-reperfusion injury group (SIR group), using a random number table, and sham-operation groups (IR-Sham group, STS-Sham group, and SIR-Sham group) were also established. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured, and the histomorphological changes of the liver were observed, as well as the expression of Sirt1, LC3B, and P62 proteins in liver tissue and the results of LC3B fluorescence staining. An analysis of variance was used for comparison of data between multiple groups, and the t-test was used for comparison of data between two groups.@*Results@#Compared with the IR group, the STS group had significant reductions in the serum levels of ALT (3 152.7 ± 735.6 U/L vs 8 414.2 ± 1 052.2 U/L, P < 0.01) and AST (3 577.0 ± 714.0 U/L vs 10 845.8 ± 1 145.7 U/L, P < 0.01) and significant alleviation of liver pathological injury (Suzuki score: 1.50±0.55 vs 3.50±0.55, P < 0.01). Compared with the STS group, the SIR group had significant increases in the serum levels of ALT (7 002.7 ± 1 485.2 U/L vs 3 152.7 ± 735.6 U/L, P < 0.01) and AST (8 980.7 ± 1 739.1 U/L vs 3 577.0 ± 714.0 U/L, P < 0.01) and significant exacerbation of liver pathological injury (Suzuki score: 3.33 ± 0.52 vs 1.50 ± 0.55, P < 0.01). Compared with the IR group and the IR-Sham group, the STS group and the STS-Sham group had significant increases in the mRNA and protein expression of Sirt1 and the protein expression of LC3B and a significant reduction in the protein expression of P62, as well as a significant increase in the percentage of LC3B-positive cells in liver tissue (22.83% ± 5.19% / 22.17% ± 4.83% vs 10.16% ± 3.06% / 10.83% ± 1.94%, both P < 0.01). Compared with the STS group and the STS-Sham group, the SIR group and the SIR-Sham group had significant reductions in the expression of Sirt1 and LC3B proteins and a significant increase in the expression of P62 protein, as well as a significant reduction in the percentage of LC3B-positive cells in liver tissue (11.83% ± 9.24% / 14.67% ± 4.68% vs 22.83% ± 5.19% / 22.17% ± 4.83%, both P < 0.01).@*Conclusion@#STS can effectively alleviate hepatic ischemia-reperfusion injury, and its protective effect may be associated with increasing the expression of Sirt1, inducing and promoting hepatocyte autophagy, and reducing hepatocyte death.

14.
Neotrop. ichthyol ; 15(2): e160027, 2017. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-841899

ABSTRACT

The effects of the timing of first feeding on the point-of-no-return (PNR) and growth of laboratory reared silver catfish Rhamdia voulezi larvae were studied. The experiment began immediately after the complete absorption of the yolk sac, 3 days after hatching (DAH). The food was provided for the first time on 3rd, 4th, 5th, 6th, 7th, 8th, and 9th DAH. Zooplankton and newly-hatched Artemia spp. were used to feed the larvae. To evaluate the effect of food deprivation on growth, the standard length and weight of 594 larvae were assessed. Larval growth was significantly affected by the time of first exogenous feeding. The larvae fed from 3rd to 5th DAH showed a significantly higher development than those fed from 6th DAH. The larvae reached the PNR on 6th DAH. Survival and larval growth strongly depended on the timing of initial feeding. In order to avoid potential mortality by starvation and obtain good growth, the silver catfish larvae R. voulezi must establish successful initial feeding within 5 days after hatching.(AU)


Os efeitos do tempo da alimentação inicial sobre o ponto de não retorno (PNR) e o crescimento de larvas de jundiá Rhamdia voulezi foram estudados em condições laboratoriais. O experimento foi iniciado imediatamente após a completa absorção do saco vitelínico, 3 dias após a eclosão (DAE). O alimento foi fornecido pela primeira vez no 3o, 4o, 5o, 6o, 7o, 8o e 9o DAE. Zooplâncton e Artemia spp. recém-eclodida foram usados para a alimentação das larvas. Para avaliar os efeitos da privação alimentar sobre o crescimento, o comprimento padrão e peso de 594 larvas foram analisados. O crescimento larval foi significativamente afetado pelo tempo da primeira alimentação exógena. As larvas que receberam alimento do 3 o ao 5 o DAE apresentaram desenvolvimento significativamente maior que aquelas alimentadas mais tardiamente, a partir do 6 o DAE. As larvas alcançaram o PNR no 6 o DAE. A sobrevivência e o crescimento das larvas dependem do momento da alimentação inicial. Para evitar a mortalidade em massa e obter bom crescimento, as larvas de R. voulezi precisam estabelecer com sucesso a alimentação inicial até o 5 o dia após a eclosão.(AU)


Subject(s)
Catfishes/abnormalities , Catfishes/growth & development , Catfishes/metabolism , Animal Feed/analysis , Larva/growth & development
15.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467194

ABSTRACT

Abstract Neotropical nectar-feeding bats consume large amounts of sugar and use most of their energy-rich diet directly from the bloodstream, suggesting an adaptation towards lower body energy reserves. Here we tested the hypothesis that bats Glossophaga soricina spare the energy costs of storing energy reserves, even if this would represent a risky susceptibility during fasting. Blood glucose concentrations in 18 h fasted bats showed a 40% decrease. Breast muscle and adipose tissue lipids, as well as carcass fatty acids and liver glycogen, were also decreased following fasting. The inability to keep normoglycemia following a short-term fasting (i.e. 28 h) confirm that nectar bats invest little on storing energy reserves and show a severe fasting susceptibility associated to this pattern. Our study also support the general hypothesis that evolutionary specializations towards nectar diets involve adaptations to allow a decreased body mass, which reduces the energy costs of flight while increases foraging time.


Resumo Morcegos nectarívoros que ocorrem na região Neotropical consomem grandes quantidades de carboidratos, e usam a energia obtida da dieta diretamente, a partir da glicose na circulação sanguínea. Esta adaptação sugere que morcegos nectarívoros tenham evoluído no sentido de apresentar adaptações fisiológicas que permitam o baixo armazenamento de reservas energéticas corporais. Nós testamos a hipótese de que morcegos Glossophaga soricina poupam o gasto energético envolvido com a formação de reservas energéticas teciduais, mesmo que isso represente uma arriscada suscetibilidade da espécie frente ao jejum. As concentrações de glicose apresentaram uma diminuição de 40% após 18 h de jejum. As concentrações de lipídios do músculo peitoral e do tecido adiposo, bem como as de ácidos graxos da carcaça e glicogênio hepático também diminuíram após 18 h de jejum. A incapacidade de manter a normoglicemia observada após o jejum de curto-prazo confirma que morcegos nectarívoros desta espécie não investem na formação de reservas energéticas, e apresentam, consequentemente, uma severa susceptibilidade ao jejum. Este estudo suporta a hipótese de que adaptações evolucionárias da espécie envolvem diminuição da massa corporal, reduzindo o custo energético do voo e aumentado o tempo de forrageamento.

16.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467259

ABSTRACT

Abstract Stresses can be caused by multiple biotic and abiotic factors and their effects can affect both the biology and the immune system of insects. American cockroach Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae) besides being an excellent model species, has great medical importance because it can act as a mechanical vector of several pathogens. This study aimed to evaluate the influence of starvation, dehydration and both stresses on weight, and total and differential haemocyte count in P. americana adults. Each specimen was isolated in glass flasks containing or not food and/or water. They were weighed periodically. Another group received water for 24 h after the end of stress period. In the immunologic bioassay, we counted their haemocytes after the final weighing. All stresses reduced the insect weight, especially when the stresses were combined. Females of the control group gained weight and males had it unaltered. Different stress conditions and time did not influence on total haemocyte count. Insects without food and water had the proportion of prohaemocytes increased and plasmatocytes decreased. This study can serve as a basis of further studies of bioecology, behaviour and the ability of resisting insecticides, besides serving as a model to studies in other insect species.


Resumo Os estresses podem ser causados por múltiplos fatores bióticos e abióticos e seus efeitos podem afetar tanto a biologia como o sistema imune dos insetos. A barata-americana Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae) além de ser uma excelente espécie modelo, tem grande importância médica, pois pode atuar como vetor mecânico de diversos patógenos. O objetivo desse estudo foi avaliar a influência da inanição, desidratação e ambos os estresses sobre o peso e o número total e diferencial de hemócitos em adultos de P. americana. Cada espécime foi isolado em frascos de vidro contendo ou não alimento e/ou água. Eles foram pesados periodicamente. Outro grupo recebeu água por 24 h após o término do período de estresse. Nos ensaios imunológicos, foram contados os seus hemócitos após a última pesagem. Todos os estresses reduziram o peso dos insetos, especialmente quando os estresses foram combinados. As fêmeas do grupo controle ganharam peso e os machos tiveram seu peso inalterado. As diferentes condições de estresse e tempo não influenciaram no número total de hemócitos. Os insetos sem alimento e água tiveram a proporção de pró-hemócitos aumentada e a de plasmatócitos reduzida. Esse estudo pode servir como base para estudos posteriores de bioecologia, comportamento e da habilidade de resistir aos inseticidas químicos, além de servir como modelo para estudos em outras espécies de insetos.

17.
World Science and Technology-Modernization of Traditional Chinese Medicine ; (12): 229-234, 2017.
Article in Chinese | WPRIM | ID: wpr-609213

ABSTRACT

This study aimed at exploring the effects of Griffipavixanthone,a natural small molecule extracted from Garcinia esculenta,on the autophagy and the mechanism behind it.Cervical cancer HeLa cells were selected as the model in vitro.Confocal microscopy,flow cytometry and immunoblotting were performed to know the impacts of Griffipavixanthone on signaling pathway over autophagy flux and calcium level;while nude mouse model was established to explore its anti-cancer action in vivo.It was found that Griffipavixanthone significantly induced GFP-LC3 puncta formation and the accumulation of LC3-Ⅱ/LC3-Ⅰ,and increased the protein expression of SQSTM1 in HeLa cells in a time and concentration dependent manner.MTT assay results showed that Griffipavixanthone inhibited the growth of HeLa cells in a dosage dependent manner,and eliminated the tolerance of tumor cells to nutrient starvation,which fastened the death of cells.Griffipavixanthone also down-regulated the concentration of calcium in the cytoplasm.Furthermore,the in vivo study indicated that intratumoral injection of Griffipavixanthone presented the anti-cancer effect to a certain extent.In conclusion,it was suggested that Griffipavixanthone inhibit autophagy with the potential to be developed into a clinical anti-cancer agent.Griffipavixanthone sensitized HeLa cells to nutrient stress-induced cell death through inhibiting the autophagy flux and the level of calcium in the cytoplasm.

18.
Acta Anatomica Sinica ; (6): 14-18, 2017.
Article in Chinese | WPRIM | ID: wpr-844696

ABSTRACT

Objective To explore the effect of intermittent starvation on neurofilament phosphorylation and spatial learning and memory in rats induced by sodium nitrite. Methods Thirty-six rats were randomly divided into control, NaNO2 and stavation + NaNO2 groups, 12 rats in each group. NaNO2 group and slavation + NaNO2 group rats were served as drinking water containing sodium nitrite [100mg/(kg · d)]. Starvation + NaNO2 group rats were deprived of food for 2 days, and then re-feeded for 3 days. Sixty days later, the ability of spatial learning and memory of the rats was measured by Morris water maze. Phosphorylation level of neurofilament in the hippocampus was detected by immunohistochemistry and Western blotting. Results In comparison with the control rats, the NaNO2 rats showed significantly longer latency to find the hidden platform from 2 days to 7 days in Morris water maze (control group latency: 31.24 ± 8.53, 12.41 ± 6.54, 10.49 ± 6.43, 8.61 ±2.56, 7.25 ±2.12, 6.03 ±1.92; NaNO2 group latency: 53.34 ±5.28, 35.15 ± 10.29, 23.52 ±9.50, 14.49 ±8.70, 16.87 ±8.77, 12.31 ±7.12) (P<0.05, P <0.01), and elevated phosphorylation level of neurofilament, while stavation + NaNO2 group rats only showed longer latency on 2 days and 3 days(43.61 ± 1.76, 25.25 ±7.49) in Morris water maze. There was no obvious difference in phosphorylation level of neurofilament between the control and stavation + NaNO2 group. Conclusion Intermittent starvation attenuates neurofilament phosphorylation and spatial learning and memory disorder induced by sodium nitrite in rats.

19.
Br J Med Med Res ; 2016; 11(9):1-19
Article in English | IMSEAR | ID: sea-182048

ABSTRACT

Cancer therapy has been a major scientific and medical focus for decades, treatment of which has proven to be a challenging task, especially in the light of its escalating incidence all over the globe. The material and moral costs of understanding the nature of the disease and finding successful ways of treatment have been extremely high. One major experimental addition to the methods of dealing with the various types of cancer has been the use of starvation protocols that may halt or delay the progression of malignant cells. In this review, a comprehensive and a pioneering account of the literature on starvation therapy is being demonstrated with an emphasis on the experimental and clinical evidence that exist, in addition to the molecular mechanisms and cellular alterations that accompany the starvation. The major objectives were to open ways for further research into understanding the topic and developing suitable and effective methods based on nutritional manipulations, for combating malignancies. The starvation includes precursors of growth such as energy precursors and others such as amino acids, nucleic acids, in addition to environmental manipulations such as abnormal oxygenation. Additional emphasis has highlighted the synergistic effects of combining conventional chemotherapy and radiotherapy with various modes of the artificial starvation. Methods of manipulating nutritional precursors have also been compiled. Additionally, negative effects of starvation were also briefly explained in an attempt to comprehend future guidelines for antagonizing such negative effects.

20.
China Journal of Chinese Materia Medica ; (24): 1397-1404, 2016.
Article in Chinese | WPRIM | ID: wpr-320846

ABSTRACT

This paper was aimed to compare the acute toxicity of 999 Ganmaoling grain and its different ingredients, and investigate the influence of routine diet on the hepatic toxicity induced by Ganmaoling in mice, so as to provide experimental basis for the clinical safety evaluation. Mice were given a single dose of Ganmaoling grain or its different ingredients respectively by gavage, and then observed for 14 days. LD₅₀ values of Ganmaoling grain or its chemical ingredient and the maximal tolerated dose of its herb ingredient were determined. Mice were divided into starvation and diet group, a single dose of Ganmaoling grain was administered by gavage. LD₅₀ values were estimated after 14 day observation. Mice were divided into starvation and diet group. At the same time,control group was set up for each. A single dose of Ganmaoling grain was given. Serum biochemical indexes were detected, liver weight index was calculated and liver tissue morphological change was observed after 6 h. LD₅₀ values were 4.42, 0.64 g•kg⁻¹ for Ganmaoling grain group and chemical ingredient group, respectively. The maximal tolerated dose of the herb ingredient group was close to 24.24 g•kg⁻¹. The toxic symptom was basically similar in the Ganmaoling grain and the chemical ingredient group. The body weight and food intake were decreased to a certain extent in both groups. There were pathological changes of liver and heart tissue in some of the surviving animals. The animals in the Ganmaoling grain group exhibited a lighter toxicity and recovered faster than that in the chemical ingredient group. LD₅₀ values of Ganmaoling grain were 2.56, 6.93 g•kg⁻¹ for starvation and diet group respectively. TD₅₀ values were 1.29, 6.31 g•kg⁻¹ for starvation and diet group respectively. The toxicity of 999 Ganmaoling was less, which may be related to the reduction of toxicity after the combination of herb and chemical ingredients. Compared with starvation group, the values of LD₅₀ and TD₅₀ of diet group was significantly increased, and toxicity was decreased. From the point of view of safety, it is safer to use Ganmaoling in the absence of hunger or after meal. The above tests provide experimental basis for the clinical safety use of Ganmaoling.

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