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1.
Prolonged QT interval is an independent risk factor for development of ventricular arrhythmias. Haloperidol is one of the drugs inducing QT prolongation. Previous studies showed that haloperidol affects not only QT duration but also heart rate (RR interval). The present work focused on relationship between QT and RR and its changes under acute and chronic haloperidol administration. The study included 14 male guinea pigs divided into control and haloperidol-treated group. After 21-days administration of haloperidol or vehiculum, electrograms in isolated hearts were recorded. QT/RR and dQT/dRR coupling were calculated. Chronic haloperidol administration significantly decreases the coupling between QT and RR. Acute haloperidol exposure significantly decreases the dQT/dRR coupling in both treated and untreated guinea pig hearts. Flatter QT/RR relationship reveals a lack of QT adaptation to increased heart rate. It should be emphasized that in such situation ECG recording will not show significant QT prolongation evaluated according to clinical rules. However, if QT interval does not adapt to increased heart rate sufficiently, the risk of ventricular arrhythmias may be increased despite practically normal QT interval length. The results are supported by findings in biochemical analyses, which proved eligibility of the used model.  相似文献   
2.
The objective of the present study was to evaluate the effects of low-molecular-weight chitosan (LMWC) on the growth performance, immune responses and intestinal health of weaned pigs challenged by enterotoxigenic Escherichia coli (ETEC). A total of 32 weaned pigs were randomly allocated to four treatments: non-challenged (fed with basal diet), ETEC-challenged (fed with basal diet) and ETEC-challenged plus 50 or 100 mg/kg LMWC supplementation, respectively. After 11 days feeding, the non-challenged pigs were infused with sterilised Luria–Bertani culture, while the remaining pigs were infused with 2.6 × 1011 colony-forming units of ETEC. At 3 days post-challenge, all pigs were administered d-xylose at 0.1 g/kg body weight. One hour later, blood samples were obtained, and the pigs then euthanised to collect intestinal samples. Data showed that only 100 mg/kg LMWC supplementation attenuated (P < 0.05) the average daily gain reduction caused by ETEC. Furthermore, besides the decreased (P < 0.05) serum tumour necrosis factor-α and immunoglobulin (Ig) G concentrations detected in ETEC-challenged pigs supplemented with LMWC at 50 or 100 mg/kg, the higher dose (100 mg/kg) also decreased (P < 0.05) the serum IgM concentration and increased (P < 0.05) the villus height and villus height-to-crypt depth ratio in both the jejunum and ileum, and the sucrase activity in the ileal mucosa. Moreover, LMWC supplementation (50 or 100 mg/kg) in ETEC-challenged pigs elevated (P < 0.05) the mRNA levels of jejunal mucosal peptide transporter 1 and ileal mucosal peptide transporter 1, divalent metal transporter 1 and zinc transporter 1, and decreased (P < 0.05) the ileal and caecal E. coli abundances, while 100 mg/kg LMWC additionally elevated (P < 0.05) the ileal Bacillus abundance, and caecal and colonic Bifidobacterium abundances. These results suggest that LMWC helps alleviate ETEC-induced growth retardation in weaned pigs, which could be associated with the inhibition of the immune responses and improved intestinal health.  相似文献   
3.
Interactions between host and gut microbiota in domestic pigs: a review   总被引:1,自引:0,他引:1  
ABSTRACT

It is well established that pig gut microbiota plays a critical role in maintaining metabolic homeostasis as well as in a myriad of physiological, neurological and immunological functions; including protection from pathogens and digestion of food materials – some of which would be otherwise indigestible by the pig. A rich and diverse gut microbial ecosystem (balanced microbiota) is the hallmark of good health; while qualitative and quantitative perturbations in the microbial composition can lead to development of various diseases. Alternatively, diseases caused by stressors or other factors have been shown to negatively impact the microbiota. This review focuses primarily on how commensal microorganisms in the gastrointestinal tract of pigs influence biochemical, physiological, immunological, and metabolic processes within the host animal.  相似文献   
4.
Sexual violence against women and girls is commonplace in Papua New Guinea (PNG). While the experiences of women are rightly given central place in institutional responses to sexual violence, the men who perpetrate violence are often overlooked, an oversight that undermines the effectiveness of prevention efforts. This paper draws on interviews conducted with young men as part of a qualitative longitudinal study of masculinity and male sexuality in a rural highland area of PNG. It explores one aspect of male sexuality: men’s narratives of sexual violence. Most striking from the data is that the collective enactment of sexual violence against women and girls is reported as an everyday and accepted practice amongst young men. However, not all women and girls were described as equally at risk, with those who transgress gender roles and roles inscribed and reinforced by patriarchal structures, at greater risk. To address this situation, efforts to reduce sexual violence against women and girls require an increased focus on male-centred intervention to critically engage with the forms of patriarchal authority that give license to sexual violence. Understanding the perceptions and experiences of men as perpetrators of sexual violence is a critical first step in the process of changing normative perceptions of gender, a task crucial to reducing sexual violence in countries such as PNG.  相似文献   
5.
目的:了解江西省表观健康猪群携带猪链球菌的情况,为有效防控猪链球菌病提供科学依据。方法选取景德镇市、崇仁县为采样点,采集表观健康猪群鼻咽拭子和扁桃体进行猪链球菌病原分离鉴定。结果共采集表观健康猪群鼻咽拭子和扁桃体样本301份,检出2株猪链球菌2型,其毒力基因mrp、sly、ef均为阴性。结论本次调查中江西省表观健康猪携带猪链球菌的带菌率为0.66%。  相似文献   
6.
7.
PCV2 is globally spread pathogen involved in a number of diseases (PCVD). Commonly used vaccines against PCV2 are proved to be highly efficacious. The role of recently discovered PCV3 for pig health and interference with PCV2 remains unknown. The study performed on serum samples from seven farms vaccinated against PCV2 and four non‐vaccinated showed very low prevalence of PCV2 viremia in the former (3 out of 106 positive serum pools) and high prevalence of PCV2 viremia in the latter (35 out of 60 positive pools). Mean log10 PCV2 genome equivalents were lower in vaccinated farms (4.8 ± 0.6 log10 copies/ml) than in non‐vaccinated farms (6.3 ± 1.3 log10 copies/ml). PCV3 was detected in 31 out of 106 and 12 out of 60 serum pools from vaccinated and non‐vaccinated farms, respectively. Mean log10 PCV3 genome equivalents were significantly (p < 0.05) lower in vaccinated farms (3.9 ± 0.8 log10 copies/ml) than in non‐vaccinated farms (4.4 ± 0.6 log10 copies/ml). Concurrent PCV2 and PCV3 infection was rare and found only in 1 out of 529 and 4 out of 292 individual serum samples from vaccinated and non‐vaccinated farms, respectively. Our results showed lack of impact of PCV3 circulation on PCV2 vaccine efficacy. On the other hand, intensive PCV2 circulation and high viremia detected in non‐vaccinated farms did not seem to increase the level of PCV3 infection.  相似文献   
8.
摘要 目的 探讨普济煎液对豚鼠EB病毒的抑制及其免疫干预作用。 方法 经滴鼻、口腔接种EB病毒1周,造模成功后,把豚鼠分为5组:正常对照组、模型组、阿昔洛韦组、低剂量普济煎液组、高剂量普济煎液组,每组各9只,分别予生理盐水、阿昔洛韦、普济煎液灌胃2周。末次给药后,检测豚鼠血液淋巴细胞中EBV-DNA载量、血清中TNF-α、IL-6、IL-8、IL-10、IFN-γ、EBV-VCA IgG含量。结果 与正常对照组比较,模型组、阿昔洛韦组、低剂量普济煎液组、高剂量普济煎液组淋巴细胞中EBV-DNA拷贝数、血清中EBV-VCA IgG含量显著升高(P<0.05);与模型组比较,阿昔洛韦组、低剂量普济煎液组、高剂量普济煎液组淋巴细胞中EBV-DNA拷贝数降低(P<0.05);高剂量普济煎液组淋巴细胞中EBV-DNA拷贝数较阿昔洛韦组降低(P<0.05);与模型组比较,阿昔洛韦组、低剂量普济煎液组、高剂量普济煎液组血清中TNF-α、IL-6、IFN-γ含量升高(P<0.05);高剂量普济煎液组中TNF-α、IFN-γ含量较阿昔洛韦组升高(P<0.05)。结论 普济煎液能有效抑制EBV-DNA复制,其机制可能是通过上调TNF-α、IL-6、IFN-γ表达,降低IL-10的表达,增强豚鼠免疫应答效应,抑制EB病毒增殖。  相似文献   
9.
Crested vertebrates are known from a wide variety of modern and fossil taxa, however, the actual formation and function of the crest is still debatable. Among modern birds, the globally distributed guinea fowl (Numida meleagris) is characterized by having a cranial bony crest (overlain by keratin), but surprisingly little is known about its development. Here, we studied the crest of 202 wild guinea fowl from the same population, using anatomical measurements as well as 2D-morphometry. Our results show that juveniles have smaller skulls than adults and have smaller, simpler crests that are visible even in very young individuals. Among adults, female skulls are smaller than males, and they have smaller, simpler shaped crests, which permit a discrimination between the sexes of 93% when the keratin is preserved with the bony crest, and of 89% when only the bony crest is available. By extrapolation, these results confirm that the crest can be used as an ontogenetic character, as well as for sex discrimination in the fossil record. Our results also show that the overlying keratin does not always mimic the underlying bony crest, which should be considered when reconstructing extinct crested vertebrates. Anat Rec, 303:1018–1034, 2020. © 2019 American Association for Anatomy  相似文献   
10.
ABSTRACT

Purpose: We sought to determine the prevalence of trachomatous inflammation – follicular (TF) in children aged 1–9 years, and trachomatous trichiasis (TT) in those aged ≥15 years, in suspected trachoma-endemic areas of Papua New Guinea (PNG).

Methods: We carried out six population-based prevalence surveys using the protocol developed as part of the Global Trachoma Mapping Project.

Results: A total of 19,013 individuals were sampled for inclusion, with 15,641 (82.3%) consenting to participate. Four evaluation units had prevalences of TF in children ≥10%, above which threshold the World Health Organization (WHO) recommends mass drug administration (MDA) of azithromycin for at least three years; Western Province (South Fly/Daru) 11.2% (95% confidence interval, CI, 6.9–17.0%), Southern Highlands (East) 12.2% (95% CI 9.6–15.0%), Southern Highlands (West) 11.7% (95% CI 8.5–15.3%), and West New Britain 11.4% (95% CI 8.7–13.9%). TF prevalence was 5.0–9.9% in Madang (9.4%, 95% CI 6.1–13.0%) and National Capital District (6.0%. 95% CI 3.2–9.1%) where consideration of a single round of MDA is warranted. Cases of TT were not found outside West New Britain, in which four cases were seen, generating an estimated population-level prevalence of TT in adults of 0.10% (95% CI 0.00–0.40%) for West New Britain, below the WHO elimination threshold of 0.2% of those aged ≥15 years.

Conclusion: Trachoma is a public health issue in PNG. However, other than in West New Britain, there are few data to support the idea that trachoma is a cause of blindness in PNG. Further research is needed to understand the stimulus for the active trachoma phenotype in these populations.  相似文献   
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