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1.
Oecologia ; 191(1): 83-96, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31332519

RESUMO

Predators and parasites have been important extrinsic factors influencing the fluctuation of small mammal populations. They can have non-additive effects on a shared group of preys or hosts, which can have important consequences for population dynamics. However, experimental studies incorporating the interactions between predation and parasites are scarce in small mammal populations. Here we systematically examined the synergistic effects of predators and coccidian parasites interaction on overwinter survival and likely mechanisms underlying the synergistic effects in the root vole (Microtus oeconomus). Our aim was to test the general hypothesis that predators and coccidia interact synergistically to decrease overwinter survival of root voles through mediating vole's physiological traits and body conditions. We carried out a factorial experimental design, by which we manipulated the predator exclusion in combination with the parasitic removal in enclosures, and then measured fecal corticosterone metabolite (FCM) levels, immunocompetence, and body conditions in captured animals via repeated live trapping. We found a strong negative synergistic effect of predators and coccidia on survival. Importantly, we found that predators increased both the prevalence and intensity of coccidian infection in voles through immune suppression induced by predation stress, while increased coccidian infection reduced plasma protein and hematocrit level of voles, which may impair anti-predator ability of voles and lead to an increase in predation. Our finding showed when voles are exposed to both predation risk and infection, their synergistic effects greatly reduce overwinter survival and population density. This may be an important mechanism influencing population dynamics in small mammals.


Assuntos
Arvicolinae , Parasitos , Animais , Corticosterona , Dinâmica Populacional , Comportamento Predatório
2.
Syst Parasitol ; 96(3): 337-346, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30903446

RESUMO

We examined faeces of 76 endangered Tibetan antelopes Pantholops hodgsonii (Abel) in May 2017, from the Hoh Xil Nature Reserve, Qinghai Province, China, and found 62/76 (82%) discharging oöcysts representing five new species of Eimeria Schneider, 1875. Oöcysts of Eimeria pantholopensis n. sp., found in 54/76 (71%) chiru, are subspheroidal/ellipsoidal, 15-22 × 12-19 (18.6 × 16.1) µm, with a length/width (L/W) ratio of 1.0-1.3 (1.2); micropyle cap and 1-3 polar granules are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 7-11 × 4-6 (9.2 × 5.3) µm, with a L/W ratio of 1.6-2.0 (1.7); Stieda body and sporocyst residuum of small, scattered granules are present; each sporozoite contains 2 refractile bodies. Oöcysts of Eimeria wudaoliangensis n. sp. found in 52/76 (68%) chiru, are pyriform, 21-29 × 17-21 (24.9 × 19.0) µm, with a L/W ratio of 1.1-1.5 (1.3); micropyle, micropyle cap and 1-4 polar granules are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 9-13 × 5-8 (11.7 × 6.7) µm, with a L/W ratio of 1.4-2.7 (1.7); Stieda body and sporocyst residuum of disbursed granules are present; sporozoites have a single large refractile body. Oöcysts of Eimeria hodgsonii n. sp. found in 20/76 (26%) chiru, are elongate-ellipsoidal, 25-32 × 18-21 (28.9 × 19.8) µm, with a L/W ratio of 1.2-1.7 (1.5); micropyle, micropyle cap and 1-3 polar granules are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 11-14 × 6-7 (12.3 × 6.8) µm, with a L/W ratio of 1.7-2.1 (1.8); Stieda body and sporocyst residuum as group of large granules lying along the interface between intertwined sporozoites are present; sporozoites have 2 refractile bodies. Oöcysts of Eimeria schalleri n. sp. found in 49/76 (64.5%) chiru, are ellipsoidal, 26-36 × 19-25 (30.4 × 23.2) µm, with a L/W ratio of 1.2-1.5 (1.3); micropyle with micropyle cap and polar granules appearing as many diffuse tiny bodies are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 12-16 × 7-9 (14.2 × 7.8) µm, with a L/W ratio of 1.6-2.1 (1.8); Stieda body and sporocyst residuum are present, the latter as a group of small dispersed granules between intertwined sporozoites; sporozoites with 2 refractile bodies. Oöcysts of Eimeria sui n. sp. found in 4/76 (5%) chiru, are ovoidal, 32-38 × 26-30 (36.6 × 28.6) µm, with a L/W ratio of 1.0-1.4 (1.3); micropyle and micropyle cap and 1-3 polar granules are present, but oöcyst residuum is absent. Sporocysts are ovoidal, 15-18 × 8-10 (16.7 × 8.9) µm, with a L/W ratio of 1.7-2.1 (1.9); Stieda body and sporocyst residuum are present, the latter as a group of dispersed small granules; sporozoites with 2 refractile bodies. Five of 62 faecal samples in which oöcysts were detected (8%) had a single species infection, 13 of 62 (21%) had two species, 28 of 62 (45%) had three species and 16 of 62 (26%) had four species.


Assuntos
Antílopes/parasitologia , Coccidiose/parasitologia , Eimeria/classificação , Animais , China/epidemiologia , Coccidiose/epidemiologia , Eimeria/citologia , Fezes/parasitologia , Especificidade da Espécie
3.
Medicine (Baltimore) ; 94(32): e1254, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26266356

RESUMO

Pancreaticoduodenectomy (PD) holds high postoperative morbidity. How to resolve this issue is challenged. An additional anastomosis (Braun enteroenterostomy) following PD may decrease the postoperative morbidity, but holds conflicting results. The objective of this study is to investigate the advantages and disadvantages of Braun enteroenterostomy in PD.Clinical studies compared perioperative outcomes between the Braun group and the non-Braun group following PD before December 21, 2014 were retrieved and filtered from PubMed, EMBASE, Web of Science, the Cochrane Library, and Chinese electronic databases (VIP database, WanFang database, and CNKI database). Relevant data were extracted according to predesigned sheets. Blood loss, operating time, and postoperative mortality and morbidity were evaluated using odds ratio (OR), weighted mean difference, or standard mean difference (SMD).Ten studies concerning 1614 patients were included. No significant differences between the Braun and the non-Braun group were identified in mortality (OR: 0.65, 95% confidence interval [CI]: 0.26-1.60), intraoperative blood loss (SMD: -0.035, 95% CI: -0.253 to 0.183), postoperative pancreatic fistula (POPF) (OR: 0.67, 95% CI: 0.35-1.67), bile leakage (OR: 0.537, 95% CI: 0.287-1.004), postoperative gastrointestinal hemorrhage (OR: 1.17, 95% CI: 0.578-2.385), intraabdominal abscesses (OR: 0.793, 95% CI: 0.444-1.419), wound complications (OR: 0.806, 95% CI: 0.490-1.325), and hospital stay (SMD: -0.098, 95% CI: -0.23 to 0.033). Braun enteroenterostomy extended operating time (SMD: 0.39, 95% CI: 0.02-0.78), but it was associated with lower reoperation rate (OR: 0.380, 95% CI: 0.149-0.968), lower morbidity rate (OR: 0.66, 95% CI: 0.49-0.91), lower clinically relevant delayed gastric emptying (Grades B and C) (OR: 0.375, 95% CI: 0.164-0.858), lower nasogastric tube reinsertion (OR: 0.436, 95% CI: 0.232-0.818), and less postoperative vomiting (OR: 0.444, 95% CI: 0.262-0.755).Braun enteroenterostomy can be safely performed during PD. It is beneficial for patients and could be recommended in PD from the current published data.PROSPERO registration number: CRD42015016198.


Assuntos
Enterostomia/métodos , Pancreaticoduodenectomia/métodos , Anastomose Cirúrgica , Humanos , Tempo de Internação , Fístula Pancreática/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Reoperação
4.
Rev Neurosci ; 25(4): 527-42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24622784

RESUMO

With the occurrence of neurodegenerative diseases, such as Alzheimer's and Parkinson's disease, a number of well-functioning neurons need to be developed to make up for the loss of neurons and to restore the brain functions. Unfortunately, because the axons cannot regenerate well, brain function cannot be well compensated for even with the increasing number of newborn neurons, let alone the reformation of neural network. Cytoskeletal proteins play a crucial role in regeneration of axon. In this review, we summarize some cytoskeletal proteins, for instance, actin and actin-binding proteins, as well as tubulin and microtubule-associated proteins, and more importantly, their roles in the regulation of axonal regeneration in the brain. It will provide new opportunities for axonal regeneration after brain damage and will even bring new treatments to patients with neurodegenerative diseases.


Assuntos
Axônios/metabolismo , Sistema Nervoso Central/metabolismo , Citoesqueleto/metabolismo , Regeneração Nervosa , Animais , Axônios/fisiologia , Sistema Nervoso Central/lesões , Sistema Nervoso Central/patologia , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Humanos
5.
Chin J Integr Med ; 12(1): 46-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16571284

RESUMO

OBJECTIVE: To study the effect of Yangqixue Qufengshi Recipe (YQXQFS) on rheumatoid arthritis (RA) model mice under different genetic backgrounds. METHODS: Collagen Induced Arthritis (CIA) were established on HLA-DR4 transgenic (TG) mice and non-transgenic (NTG) mice, which partly were raised with YQXQFS, and the onset day of CIA, the level of type II collagen (CII)-reactive antibodies and the pathological scores of CIA were assessed. RESULTS: Under HLA-DR4 TG background (compared with NTG mice), the earlier onset day of CIA (11.22 +/- 3.35 days vs 16.56 +/- 4.75 days, P < 0.05) and higher level of CII-reactive antibodies (0.2274 +/- 0.1390 microg/ml vs 0.1101 +/- 0.0560 microg/ml, P < 0.05) were observed, but the pathological scores of CIA remained unchanged. YQXQFS could not influence the onset day of CIA and the level of CII-reactive antibodies, but had a certain effect on the total pathological scores (6.56 +/- 3.43 scores vs 11.11 +/- 5.64 scores) and bone erosion (0.22 +/- 0.44 scores vs 1.67 +/- 1.50 scores) of CIA on NTG mice (P < 0.05), NTG YQXQFS group compared with NTG experimental group. CONCLUSION: YQXQFS had a certain effect on RA model, but had no significant effect on HLA-DR4 related CIA.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Animais , Anticorpos/sangue , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Colágeno Tipo II/imunologia , Antígeno HLA-DR4/genética , Camundongos , Camundongos Endogâmicos , Camundongos Knockout
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