Modeling the dynamics of Hepatitis C virus with combined antiviral drug therapy: Interferon and Ribavirin

A mathematical modeling of hepatitis C virus (HCV) dynamics and antiviral therapy has been presented in this paper. The proposed model, which involves four coupled ordinary differential equations, describes the interaction of target cells (hepatocytes), infected cells, infectious virions and non-infectious virions. The model takes into consideration the addition of ribavirin to interferon therapy and explains the dynamics regarding a biphasic and triphasic decline of viral load in the model. A critical drug efficacy parameter has been defined and it is shown that for an efficacy above this critical value, HCV is eradicated whereas for efficacy lower this critical value, a new steady state for infectious virions is reached, which is lower than the previous steady state value.     

Effects of sodium butyrate supplementation on reproductive performance and colostrum composition in gilts

Nutrients are essential for the health and survival of human beings and animals. Also, they play a major role in enhancing reproductive efficiency. The aim of the current study was to investigate the effects of sodium butyrate (SB) on reproductive performance and colostrum composition in gilts. A total of 40 Large White×Landrace replacement gilts (at the age of 160 to 175 days) were fed either a standard diet (control group, n=20) or standard diet top dressed with encapsulated SB at the level of 500 mg/kg (SB group, n=20) from 1 month before mating to 7 days after farrowing. The rate of gilts regular return to estrus after insemination was lower in SB group than the control group. The total number of piglets born (P=0.179) and the litter weight at birth (P=0.063) did not differ between the two treatment groups. However, the mean BW at day 7 tended to be greater in SB group (P=0.051) and average daily gain of piglets was greater (P=0.011) compared with control group. Colostrum samples were collected at parturition and the concentrations of total protein (P=0.197), cholesterol (P=0.161) and lactose (P=0.923) were not influenced by SB supplementation. However, compared with control gilts, colostrum from SB-treated gilts contained lower triglyceride (P=0.050). Moreover, colostrum concentrations of prolactin (P=0.005) and leptin (P=0.006) were significantly lower in SB group. No significant differences were noted for the colostral concentrations of cortisol (P=0.899), thyroxine (P=0.891) or triiodothyronine (P=0.194). The concentration of lipopolysaccharide in colostrum was not influenced by SB supplementation (P=0.972). However, colostrum from SB-treated gilts had significantly lower tumor necrosis factor α (TNFα) (P=0.030) and higher immunoglobulin A (IgA) (P=0.042). Collectively, SB supplementation could reduce the rate of gilts return to estrus, alter the composition of colostrum and enhance the growth rate of piglets. Moreover, SB could alter the immune function of newborn piglets through decreased production of TNFα and increased IgA concentration in colostrum.     

抗感染活性骨治疗感染性胫骨骨不连的临床研究

目的:观察抗感染活性骨(ARBX)治疗感染性胫骨骨不连的临床效果。方法:回顾性分析我院自2008年1月-2015年1月收治并系统随访应用抗感染骨治疗的36例创伤后感染性骨不连病例,给予原内固定取出或外架拆除,病灶清除,去除硬化骨及死骨,髓腔再通,抗感染活性骨植骨,外架或钢板重新固定,统计患者病程时间,伤口愈合时间,患者院前手术次数,滴注引流时间及抗生素应用疗程,骨性愈合时间,内、外固定物拆除时间以及功能恢复情况,并总结治疗疗效。结果:平均随访2.4年(1年2月-4年10月),骨不连彻底治愈30例,4例患者感染控制,半皮质愈合,2例感染复发,骨不连未愈合。结论:1抗感染活性骨是治疗感染性骨不连的一种有效的植骨材料,具有控制感染,促进骨折愈合的作用;2彻底清除坏死,失活组织是控制感染,促进感染性骨不连愈合的关键;3清理断端,断端骨髓腔再通可促进成骨,促进骨折愈合。     

Effect of Conidiobolus coronatus on the Cuticular and Internal Lipid Composition of Tettigonia viridissima Males

Conidiobolus coronatus is an entomopathogenic fungus which has a potential as a biological control agent of insects. The cuticular and internal lipid composition of infected and noninfected Tettigonia viridissima males were analyzed by GC/MS. A total of 49 compounds were identified in the infected and noninfected males, including fatty acids, fatty acid methyl esters (FAMEs), n‐alkanes, alcohols, sterols, and other organic compounds. The most abundant components of the cuticular and internal lipids of the insects were fatty acids. After exposure to C. coronatus, the cuticular lipids of the T. viridissima males contained 17 free fatty acids from C(8) to C(22), while the cuticular lipids of the noninfected insects contained only 15 fatty acids from C(12) to C(24). The cuticular and internal lipids of both the infected and the noninfected males also contained five FAMEs from C(15) to C(19), seven n‐alkanes from C(25) to C(34), five alcohols from C(16) to C(25), five sterols, and the following six other organic compounds: azelaic acid, phenylacetic acid, glutaric acid, benzoic acid, sebacic acid, and glycerol. The compounds which were present only in the cuticular lipids of the infected males could be due to fungal infection.     

新生猪缺氧后心肌连接蛋白Cx43表达的变化

目的探讨新生猪缺氧后心肌连接蛋白Cx43 mRNA和蛋白含量的变化。方法对照组(C组):新生猪6头,未吸入低氧;缺氧组(H组):新生猪6头,吸入低氧(FiO2=0.1)维持1 h。于缺氧结束后5 h,免疫荧光染色检测心肌组织细胞缝隙连接蛋白Cx43蛋白的表达,实时荧光定量逆转录多聚酶链式反应(RT-PCR)检测心肌组织Cx43 mRNA的表达。结果H组心肌组织Cx43蛋白的表达显著低于C组(P<0.01),但两组心肌组织Cx43 mRNA表达差异无统计学意义(P>0.05)。结论缺氧可导致心肌Cx43蛋白的表达或分布发生变化。     

Influence of colostrum intake on piglet survival and immunity

Colostrum intake from birth to 24 h after the onset of parturition (T24) was estimated for 526 piglets from 40 litters. Plasma concentrations of immunoglobulin G (IgG), lactate, glucose and cortisol were determined at T24 for six piglets per litter. Plasma IgG concentration was also assayed at weaning (28 days) on the same piglets. Rectal temperature was measured at T24 on all piglets. Mortality was recorded until weaning and comparisons were made between piglets that died before weaning and those that were still alive at weaning. The piglets that died before weaning had lower birth weight, lower colostrum intake, lower weight gain between birth and T24, and had a lower rectal temperature, higher plasma cortisol concentration and lower plasma IgG and glucose concentrations at T24 than piglets still alive at weaning. In addition, a higher proportion of piglets that died before weaning had difficulty taking their first breath after birth and were affected by splayleg. Considering all piglets, colostrum intake was positively related to rectal temperature and plasma glucose concentration and negatively related to plasma cortisol concentration at T24. Plasma IgG concentration at T24 was explained by colostrum intake, IgG concentration in the ingested colostrum, birth weight and birth rank (P<0.0001). Plasma IgG concentration at weaning was related to plasma IgG concentration at T24 (r=0.54; P<0.0001) and to colostrum intake (r=0.32; P<0.0001). Finally, body weight was explained by colostrum intake, birth weight and age until 6 weeks of age (P<0.0001). These results show that colostrum intake is the main determinant of piglet survival through provision of energy and immune protection and has potential long-term effects on piglet growth and immunity.     

Influence of some sow characteristics on within-litter variation of piglet birth weight

Within-litter variation of piglet birth weight (BW0) is associated with an increased piglet mortality and a high variability in pig weight at weaning and weight or age at slaughter. Data collected in two experimental herds were used to quantify within-litter variability in BW0 and to assess the influence of factors mainly related to the sow. Within 24 h after birth, piglets born alive were individually weighed and stillborn piglets were collectively (first data set) or individually (second data set) weighed. The first data set was restricted to litters with no or only one stillborn piglet (3338 litters). It was used to assess the influence of genetic selection on BW0 variation by comparing litter characteristics before (1994 to 1996) and after (2001 to 2004) the development of hyperprolific sows in this herd. The second data set included all litters (n = 1596) from sows born between 2000 and 2004. For each litter, mean BW0 (mBW0) and its coefficient of variation (CVBW0) were calculated. Then, variance analyses were performed to test the influence of litter size, parity, year of sow birth and season at conception. Prolificacy improvement was associated with an increased CVBW0 in litters from pure Large White (LW) and Landrace × Large White (LR × LW) crossbred sows. The CVBW0 averaged 21% and was significantly influenced by litter size and parity. It increased from 15% to 24% when litter size varied from less than 10 piglets to more than 15 piglets. The proportion of small piglets (i.e. weighing less than 1 kg) increased concomitantly. The CVBW0 was not repeatable from a parity to the following. It was lowest for first and second parities (20%) and thereafter increased progressively. The CVBW0 was positively related to sow's backfat thickness gain during gestation. Taking into account litter size, parity, year of sow birth and season at conception explained 20% of BW0 variation. Thus, major part of heterogeneity is due to other factors, presumably including embryo genotype, on the one hand, and factors that influence embryo and foetus development, such as epigenetic factors, on the other hand.     

仔猪腹泻抗性相关特异表达ESTs的筛选

以久仰香猪、剑白香猪和长白猪3个品种的脾脏为材料,以品种间同一组织不同的发病状态为对照,将DDRT—PCR技术与银染法相结合进行差异显示研究,筛选与仔猪腹泻抗性相关的特异表达ESTs。在脾脏未发病RNA池中检测到5条特异表达ESTs,其中一条与Nck转导蛋白同源,一条与长散布元件反转录酶同源,一条为相似性较高的未知功能序列,两条为新序列。     

Effects of fermented soybean meal on carbon and nitrogen metabolisms in large intestine of piglets

Fermented soybean meal (FSM), which has lower anti-nutritional factors and higher active enzyme, probiotic and oligosaccharide contents than its unfermented form, has been reported to improve the feeding value of soybean meal, and hence, the growth performance of piglets. However, whether FSM can affect the bacterial and metabolites in the large intestine of piglets remains unknown. This study supplemented wet-FSM (WFSM) or dry-FSM (DFSM) (5% dry matter basis) in the diet of piglets and investigated its effects on carbon and nitrogen metabolism in the piglets’ large intestines. A total of 75 41-day-old Duroc×Landrace×Yorkshire piglets with an initial BW of 13.14±0.22 kg were used in a 4-week feeding trial. Our results showed that the average daily gain of piglets in the WFSM and DFSM groups increased by 27.08% and 14.58% and that the feed conversion ratio improved by 18.18% and 7.27%, respectively, compared with the control group. Data from the prediction gene function of Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) based on 16S ribosomal RNA (rRNA) sequencing showed that carbohydrate metabolism function families in the WFSM and DFSM groups increased by 3.46% and 2.68% and that the amino acid metabolism function families decreased by 1.74% and 0.82%, respectively, compared with the control group. These results were consistent with those of other metabolism studies, which showed that dietary supplementation with WFSM and DFSM increased the level of carbohydrate-related metabolites (e.g. 4-aminobutanoate, 5-aminopentanoate, lactic acid, mannitol, threitol and β-alanine) and decreased the levels of those related to protein catabolism (e.g. 1,3-diaminopropane, creatine, glycine and inosine). In conclusion, supplementation with the two forms of FSM improved growth performance, increased metabolites of carbohydrate and reduced metabolites of protein in the large intestine of piglets, and WFSM exhibited a stronger effect than DFSM.     

Effect of oral progesterone and caffeine at the end of gestation on farrowing duration and piglet growth and survival

The profitability of pig production is constrained by high incidences of peri-parturient and pre-weaning piglet mortality. Supplementing sows with either progesterone or caffeine during the last week of gestation can reduce stillbirths and improve piglet performance. However, the consequences of combining these two substances has not been investigated. The aim of the current study was to determine the effect of oral supplementation of sows with progesterone (regumate) and caffeine at the end of gestation on the timing and progression of farrowing, as well as piglet survival and growth to weaning. From days 111 to 113 of gestation, 20 Large White pregnant sows (parity 3.0±0.45) received 5 ml of Regumate Porcine (0.4 w/v oral solution; MSD Animal Health) daily on top of their morning ration. Sows were stratified according to parity and predicted farrowing date, and allocated at random to receive a diet supplemented with either 0 g caffeine/kg diet (CONT) or 2.4 g of caffeine/kg diet (CAFF) from day 113 of gestation until parturition (n=10 sows/treatment). Treatment did not affect total litter size; however, CONT sows gave birth to more live and fewer dead piglets compared with CAFF sows; 14.5±0.73 v. 11.7±1.03 and 0.7±0.20 v. 3.2±0.77; P<0.05). Mean, minimum and maximum piglet birthweight were unaffected by treatment. Compared with the control, caffeine increased the proportion of piglets with a birthweight <1 kg (0.16±0.05 v. 0.05±0.02; P=0.072) and decreased the proportion of live born piglets surviving to day 5 postpartum (0.77±0.06 v. 0.90±0.02; P<0.05) and to weaning (0.74±0.06 v. 0.90±0.02; P<0.05). Overall, the current data provided the first evidence that caffeine supplementation of sows receiving progesterone to prevent premature farrowing impaired piglet survival during, and shortly after parturition. This negative outcome may be linked to extended farrowing durations and an increase in the proportion of very light piglets at birth. These data provide compelling, albeit preliminary, evidence that caffeine and progesterone should not be used together at the end of gestation.