BackgroundMetallothioneins are ubiquitous small, cysteine-rich, multifunctional proteins which can bind heavy metals.Methodology/Principal FindingsWe report the results of phylogenetic and gene expression analyses that include two new Tetrahymena thermophila metallothionein genes (MTT3 and MTT5). Sequence alignments of all known Tetrahymena metallothioneins have allowed us to rationalize the structure of these proteins. We now formally subdivide the known metallothioneins from the ciliate genus Tetrahymena into two well defined subfamilies, 7a and 7b, based on phylogenetic analysis, on the pattern of clustering of Cys residues, and on the pattern of inducibility by the heavy metals Cd and Cu. Sequence alignment also reveals a remarkably regular, conserved and hierarchical modular structure of all five subfamily 7a MTs, which include MTT3 and MTT5. The former has three modules, while the latter has only two. Induction levels of the three T. thermophila genes were determined using quantitative real time RT-PCR. Various stressors (including heavy metals) brought about dramatically different fold-inductions for each gene; MTT5 showed the highest fold-induction. Conserved DNA motifs with potential regulatory significance were identified, in an unbiased way, upstream of the start codons of subfamily 7a MTs. EST evidence for alternative splicing in the 3′ UTR of the MTT5 mRNA with potential regulatory activity is reported.Conclusion/SignificanceThe small number and remarkably regular structure of Tetrahymena MTs, coupled with the experimental tractability of this model organism for studies of in vivo function, make it an attractive system for the experimental dissection of the roles, structure/function relationships, regulation of gene expression, and adaptive evolution of these proteins, as well as for the development of biotechnological applications for the environmental monitoring of toxic substances.
We evaluated treatment outcomes in a prospective registry of human immunodeficiency virus/hepatitis C virus (HCV)–coinfected patients treated with interferon‐free direct‐acting antiviral agent–based therapy in hospitals from the region of Madrid between November 2014 and August 2016. We assessed sustained viral response at 12 weeks after completion of treatment and used multivariable logistic regression to identify predictors of treatment failure. We evaluated 2,369 patients, of whom 59.5% did not have cirrhosis, 33.9% had compensated cirrhosis, and 6.6% had decompensated cirrhosis. The predominant HCV genotypes were 1a (40.9%), 4 (22.4%), 1b (15.1%), and 3 (15.0%). Treatment regimens included sofosbuvir (SOF)/ledipasvir (61.9%), SOF plus daclatasvir (14.6%), dasabuvir plus ombitasvir/paritaprevir/ritonavir (13.2%), and other regimens (10.3%). Ribavirin was used in 30.6% of patients. Less than 1% of patients discontinued therapy owing to adverse events. The frequency of sustained viral response by intention‐to‐treat analysis was 92.0% (95% confidence interval, 90.9%‐93.1%) overall, 93.8% (92.4%‐95.0%) for no cirrhosis, 91.0% (88.8%‐92.9%) for compensated cirrhosis, and 80.8% (73.7%‐86.6%) for decompensated cirrhosis. The factors associated with treatment failure were male sex (adjusted odds ratio, 1.75; 95% confidence interval, 1.14‐2.69), Centers for Diseases Control and Prevention category C (adjusted odds ratio, 1.65; 95% confidence interval, 1.12‐2.41), a baseline cluster of differentiation 4–positive (CD4+) T‐cell count <200/mm3 (adjusted odds ratio, 2.30; 95% confidence interval, 1.35‐3.92), an HCV RNA load ≥800,000 IU/mL (adjusted odds ratio, 1.63; 95% confidence interval, 1.14‐2.36), compensated cirrhosis (adjusted odds ratio, 1.35; 95% confidence interval, 0.96‐1.89), decompensated cirrhosis (adjusted odds ratio, 2.92; 95% confidence interval, 1.76‐4.87), and the use of SOF plus simeprevir, SOF plus ribavirin, and simeprevir plus daclatasvir. Conclusion: In this large real‐world study, direct‐acting antiviral agent–based therapy was safe and highly effective in coinfected patients; predictors of failure included gender, human immunodeficiency virus–related immunosuppression, HCV RNA load, severity of liver disease, and the use of suboptimal direct‐acting antiviral agent–based regimens. (Hepatology 2018;68:32‐47).
Avian pox is a widespread infection in birds caused by genus Avipoxvirus pathogens. It is a noteworthy, potentially lethal disease to wild and domestic hosts. It can produce two different conditions: cutaneous pox, and diphtheritic pox. Here, we carry out an exhaustive review of all cases of avian pox reported from wild birds to analyze the effect and distribution in different avian species. Avian poxvirus strains have been detected in at least 374 wild bird species, a 60% increase on a 1999 review on avian pox hosts. We also analyze epizootic cases and if this disease contributes to wild bird population declines. We frequently observe very high prevalence in wild birds in remote island groups, e.g., Hawaii, Galapagos, etc., representing a major risk for the conservation of their unique endemic avifauna. However, the difference in prevalence between islands and continents is not significant given the few available studies. Morbidity and mortality can also be very high in captive birds, due to high population densities. However, despite the importance of the disease, the current detection rate of new Avipoxvirus strains suggests that diversity is incomplete for this group, and more research is needed to clarify its real extent, particularly in wild birds.
Viral cutaneous lesions are frequent in some bird populations, though we are generally ignorant of the causal agent. In some instances, they represent a threat to livestock and wildlife health. We present here a multiplex PCR which detects and distinguishes infection by two such agents, avipoxviruses and papillomaviruses, in avian hosts. We assayed biopsies and superficial skin swabs from field and preserved museum skin specimens. Ninety-three percent of samples from symptomatic specimens tested positive for the presence of avipox (n = 23) or papillomavirus (n = 5). Sixteen and five sequences, corresponding to the P4b and L1 genes, were obtained from avipox and papillomavirus, respectively. One museum specimen, of Fringilla coelebs (chaffinch), was apparently infected with both viruses. Although papillomavirus sequences proved identical to previously published sequences, four novel avipox sequences were generated and used to build a neighbor-joining phylogenetic tree. Our tree recovered a similar topology to that of several recent authors; however, we also propose here two new minor avipox clades (B1b and B3). This multiplex PCR technique shows improved sensitivity compared to other avipox and papillomavirus assays, is able to detect a wide range of avipox and papillomavirus types (it amplifies all three avian-derived papillomavirus genera described thus far and sequences from both major avipox clades), and was even able to detect ancient viral DNA contained in museum specimens of greater than 75 years antiquity for both viruses.
Current treatment with oral nucleos(t)ides entecavir or tenofovir provide sustained suppression of HBV replication and clinical benefit in most chronic hepatitis B virus (HBV) infected persons. However, HBV rebound generally occurs upon drug discontinuation due to persistence of genomic HBV reservoirs as episomic cccDNA and chromosomic integrated HBV-DNA. There is renewed enthusiasm on HBV drug discovery following recent successes with antivirals for hepatitis C and immunotherapies for some cancers. Areas covered: New drugs that target distinct steps of the HBV life cycle are been developed, including inhibitors of viral entry, new polymerase inhibitors, capsid and assembly inhibitors, virus release blockers, and disruptors of cccDNA formation and transcription. Alongside these antivirals, agents that enhance anti-HBV specific immune responses are being tested, including TLR agonists, checkpoint inhibitors and therapeutic vaccines. Expert opinion: The achievement of a 'functional cure' for chronic HBV infection, with sustained HBsAg clearance and undetectable viremia once medications are stopped, represents the next step in the pace towards HBV elimination. Hopefully, the combination of new drugs that eliminate or functionally inactivate the genomic HBV reservoirs (cccDNA and integrated HBV-DNA) along with agents that enhance or activate immune responses against HBV will lead to a 'definitive cure' for chronic HBV infection.
Guidelines recommend evaluating persistent alteration of liver tests in HCV-infected patients after sustained virological response (SVR) and its influence on liver disease progression. We studied the prevalence, etiology, associated factors and evolutionary implications of persistent alteration of liver tests in HCV patients after direct-acting antivirals (DAA)-induced SVR. This was a prospective study of HCV-infected patients and SVR after DAA. Those with another previously diagnosed liver disease were excluded. Persistent alteration of liver tests was defined as any increase in ALT, AST or GGT at SVR12 and SVR24. Causes were determined according to standard clinical practice, including liver biopsy and follow-up transient elastography. A total of 1112 patients were included (70.8% males, median age 53 years, 38.8% cirrhosis, 34.9% interferon-experienced, 56.8% HIV-coinfected). Persistent alteration of liver tests was detected in 130/1112 patients (11.7% [95%CI: 9.7-13.6]). Its frequency differed between HCV-monoinfected (45/480: 9.4% [95%CI: 6.7-12.1]) and HIV-coinfected (85/632: 13.5% [95%CI: 10.7-16.2]) (P = .046). In multivariable analysis, cirrhosis (OR 2.12; 95%CI: 1.28-3.53; P = .004) and baseline transient elastography values (OR 1.03; 95%CI: 1.01-1.04; P = .000) were associated with persistent alteration of liver tests. The main etiologies were clinical diagnosis suggestive of nonalcoholic fatty liver disease in 47 (36.2%), alcohol in 30 (23.1%) and drug consumption in 19 (14.6%). Baseline and follow-up transient elastography was performed in 594 patients and showed a significantly different decrease in patients who did or did not have a persistent alteration of liver tests (-21.1% vs -30%, respectively; P = .003), independently of sex, HIV status or baseline TE value. In conclusion, persistent alteration of liver tests is not infrequent after SVR. It is associated with cirrhosis and baseline transient elastography, and the main cause is fatty liver. According to transient elastography changes, persistent alteration of liver tests seems to affect the course of liver disease.
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