In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
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Question: Porcine epidemic diarrhoea (PED) is a contagious enteric disease of pigs caused by a coronavirus. A double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) based on the use of monoclonal antibodies was developed for the detection of porcine epidemic diarrhoea virus (PEDV). The DAS-ELISA was compared with RT-PCR in the examination of 506 specimens collected during 2006-2007 from pigs originating from different farms located in the Po valley. Both faecal samples obtained directly from the rectum of live animals showing clinical signs and intestinal samples collected from the caecum of deceased pigs were included in the study. The correlation between the two methods was higher when testing faecal samples (K = 0.97, 95% CI: 0.94-1.00) than testing intestinal samples (K = 0.62, 95% CI: 0.35-0.89). The use of ELISA technology provided an efficient and effective mean of evaluating the presence of coronavirus PED antigen in field samples and indicates that this procedure is a very useful tool in epidemiological studies.

Answer: Comparison of enzyme-linked immunosorbent assay and RT-PCR for the detection of porcine epidemic diarrhoea virus


Question: Background/Aims: Interferon and ribavirin combination therapy for chronic hepatitis C induces a low response rate in human immunodeficiency virus (HIV) infected patients. To assess the impact of intensification of interferon administration and of the addition of amantadine on the efficacy and safety of standard anti-hepatitis C virus (HCV) treatment in HIV-infected patients. Methods: Multicentre, prospective, open-label, randomized, phase III clinical trial. Eighty co-infected patients were randomized to receive ribavirin 800 -1000 mg/day in combination with, group A: interferon alpha2a 3 MIU thrice weekly; group B: IFNa2a 3 MIU daily, plus amantadine 200 mg/day; treatment duration was 24 -48 weeks according to HCV genotype. Results: Forty-one patients were randomized in group A and 39 in group B. Intention-to-treat analysis showed a sustained virological response, defined as HCV-RNA negativization, 6 months after stopping treatment in 22% of patients from group A and 13% from group B (P > 0.05). The lack of a 2-log drop in HCV-RNA levels after 12 weeks of treatment showed a 100% predictive value of lack of sustained response. Conclusions: Amantadine addition and interferon intensification do not improve the low efficacy of combination of interferon alfa plus ribavirin in HIV/HCV co-infected patients. Patients with no early virologic response did not have any probability of sustained response. q

Answer: A randomized, controlled trial of triple antiviral therapy as initial treatment of chronic hepatitis C in HIV-infected patients q


Question: Coronaviruses (CoVs) continuously threaten human health. However, to date, the evolutionary mechanisms that govern CoV strain persistence in human populations have not been fully understood. In this study, we characterized the evolution of the major antigen-spike (S) gene in the most prevalent human coronavirus (HCoV) OC43 using phylogenetic and phylodynamic analysis. Among the five known HCoV-OC43 genotypes (A to E), higher substitution rates and dN/dS values as well as more positive selection sites were detected in the S gene of genotype D, corresponding to the most dominant HCoV epidemic in recent years. Further analysis showed that the majority of substitutions were located in the S1 subunit. Among them, seven positive selection sites were chronologically traced in the temporal evolution routes of genotype D, and six were located around the critical sugar binding region in the N-terminal domain (NTD) of S protein, an important sugar binding domain of CoV. These findings suggest that the genetic drift of the S gene may play an important role in genotype persistence in human populations, providing insights into the mechanisms of HCoV-OC43 adaptive evolution. Coronaviruses (CoVs) are widely found in humans as well as in mammalian and avian species, causing asymptomatic infections or respiratory tract disorders, and gastroenteritis of varying severity 1 . CoVs belong to the genus Coronavirus of family Coronaviridae, and are classified into four genera, Alphacoronavirus (α -CoV), Betacoronavirus (ß-CoV), Gammacoronavirus, and Deltacoronavirus based on phylogenetics and serology 1 . To date, α -CoV [including human CoV (HCoV)-229E and NL63] and ß-CoV [including HCoV-OC43, HKU1, Severe Acute Respiratory Syndrome CoV (SARS-CoV) and Middle East Respiratory Syndrome CoV (MERS-CoV)] are known to infect human beings 1 . Interspecies transmission is a common phenomenon for CoVs that may be responsible for generation of new CoV epidemics during viral evolution 2-5 . For instance, the feline CoV (FCoV) type II, a member of α -CoV, might be generated by a double recombination between FCoV type I and canine CoV 4 . Interestingly, porcine hemagglutinating encephalomyelitis virus, bovine CoV (BCoV) and HCoV-OC43 of ß-CoV are thought to have evolved from the same common ancestor 5 . During evolution, high frequencies of homologous RNA recombination and gene mutations are considered the main forces that push CoVs to adapt to specific hosts. Such events can lead to emergence of new strains or genotypes within a certain species, and even to new species, causing epidemic or zoonotic outbreaks that continuously threaten human health 2,3 . This phenomenon is exemplified by the recent emergence of SARS-CoV and MERS-CoV 6,7 . However, the detailed evolutionary mechanism of interspecies transmission and the persistence of CoVs in specific hosts have yet to be fully elucidated.

Answer:
Genetic drift of human coronavirus OC43 spike gene during adaptive evolution OPEN