scholarly journals Circulation of Type 1 Vaccine-Derived Poliovirus in the Philippines in 2001

2004 ◽  
Vol 78 (24) ◽  
pp. 13512-13521 ◽  
Author(s):  
Hiroyuki Shimizu ◽  
Bruce Thorley ◽  
Fem Julia Paladin ◽  
Kerri Anne Brussen ◽  
Vicki Stambos ◽  
...  

ABSTRACT In 2001, highly evolved type 1 circulating vaccine-derived poliovirus (cVDPV) was isolated from three acute flaccid paralysis patients and one contact from three separate communities in the Philippines. Complete genomic sequencing of these four cVDPV isolates revealed that the capsid region was derived from the Sabin 1 vaccine strain but most of the noncapsid region was derived from an unidentified enterovirus unrelated to the oral poliovirus vaccine (OPV) strains. The sequences of the cVDPV isolates were closely related to each other, and the isolates had a common recombination site. Most of the genetic and biological properties of the cVDPV isolates were indistinguishable from those of wild polioviruses. However, the most recently identified cVDPV isolate from a healthy contact retained the temperature sensitivity and partial attenuation phenotypes. The sequence relationships among the isolates and Sabin 1 suggested that cVDPV originated from an OPV dose given in 1998 to 1999 and that cVDPV circulated along a narrow chain of transmission. Type 1 cVDPV was last detected in the Philippines in September 2001, and population immunity to polio was raised by extensive OPV campaigns in late 2001 and early 2002.

2005 ◽  
Vol 79 (20) ◽  
pp. 12623-12634 ◽  
Author(s):  
Chen-Fu Yang ◽  
Hour-Young Chen ◽  
Jaume Jorba ◽  
Hui-Chih Sun ◽  
Su-Ju Yang ◽  
...  

ABSTRACT We determined the complete genomic sequences of nine type 1 immunodeficient vaccine-derived poliovirus (iVDPV) isolates obtained over a 337-day period from a poliomyelitis patient from Taiwan with common variable immunodeficiency. The iVDPV isolates differed from the Sabin type 1 oral poliovirus vaccine (OPV) strain at 1.84% to 3.15% of total open reading frame positions and had diverged into at least five distinct lineages. Phylogenetic analysis suggested that the chronic infection was initiated by the fifth and last OPV dose, given 567 days before onset of paralysis, and that divergence of major lineages began very early in the chronic infection. Key determinants of attenuation in Sabin 1 had reverted in the iVDPV isolates, and representative isolates of each lineage showed increased neurovirulence for PVR-Tg21 transgenic mice. None of the isolates had retained the temperature-sensitive phenotype of Sabin 1. All isolates were antigenic variants of Sabin 1, having multiple amino acid substitutions within or near neutralizing antigenic sites 1, 2, and 3a. Antigenic divergence of the iVDPV variants from Sabin 1 followed two major independent evolutionary pathways. The emergence of distinct coreplicating lineages suggests that iVDPVs can replicate for many months at separate sites in the gastrointestinal tract. Some isolates had mosaic genome structures indicative of recombination across and within lineages. iVDPV excretion apparently ceased after 30 to 35 months of chronic infection. The appearance of a chronic VDPV excretor in a tropical, developing country has important implications for the strategy to stop OPV immunization after eradication of wild polioviruses.


2003 ◽  
Vol 77 (20) ◽  
pp. 10994-11005 ◽  
Author(s):  
Hong-Mei Liu ◽  
Du-Ping Zheng ◽  
Li-Bi Zhang ◽  
M. Steven Oberste ◽  
Olen M. Kew ◽  
...  

ABSTRACT Type 1 wild-vaccine recombinant polioviruses sharing a 367-nucleotide (nt) block of Sabin 1-derived sequence spanning the VP1 and 2A genes circulated widely in China from 1991 to 1993. We surveyed the sequence relationships among 34 wild-vaccine recombinants by comparing six genomic intervals: the conserved 5′-untranslated region (5′-UTR) (nt 186 to 639), the hypervariable portion of the 5′-UTR (nt 640 to 742), the VP4 and partial VP2 genes (nt 743 to 1176), the VP1 gene (nt 2480 to 3385), the 2A gene (nt 3386 to 3832), and the partial 3D gene (nt 6011 to 6544). The 5′-UTR, capsid (VP4-VP2 and VP1), and 2A sequence intervals had similar phylogenies. By contrast, the partial 3D sequences could be distributed into five divergent genetic classes. Most (25 of 34) of the wild-vaccine recombinant isolates showed no evidence of additional recombination beyond the initial wild-Sabin recombination event. Eight isolates from 1992 to 1993, however, appear to be derived from three independent additional recombination events, and one 1993 isolate was derived from two consecutive events. Complete genomic sequences of a representative isolate for each 3D sequence class demonstrated that these exchanges had occurred in the 2B, 2C, and 3D genes. The 3D gene sequences were not closely related to those of the Sabin strains or 53 diverse contemporary wild poliovirus isolates from China, but all were related to the 3D genes of species C enteroviruses. The appearance within approximately 2.5 years of five recombinant classes derived from a single ancestral infection illustrates the rapid emergence of new recombinants among circulating wild polioviruses.


2019 ◽  
Vol 15 (1) ◽  
pp. 102-118 ◽  
Author(s):  
Carolina Campos-Rodríguez ◽  
José G. Trujillo-Ferrara ◽  
Ameyali Alvarez-Guerra ◽  
Irán M. Cumbres Vargas ◽  
Roberto I. Cuevas-Hernández ◽  
...  

Background: Thalidomide, the first synthesized phthalimide, has demonstrated sedative- hypnotic and antiepileptic effects on the central nervous system. N-substituted phthalimides have an interesting chemical structure that confers important biological properties. Objective: Non-chiral (ortho and para bis-isoindoline-1,3-dione, phthaloylglycine) and chiral phthalimides (N-substituted with aspartate or glutamate) were synthesized and the sedative, anxiolytic and anticonvulsant effects were tested. Method: Homology modeling and molecular docking were employed to predict recognition of the analogues by hNMDA and mGlu receptors. The neuropharmacological activity was tested with the open field test and elevated plus maze (EPM). The compounds were tested in mouse models of acute convulsions induced either by pentylenetetrazol (PTZ; 90 mg/kg) or 4-aminopyridine (4-AP; 10 mg/kg). Results: The ortho and para non-chiral compounds at 562.3 and 316 mg/kg, respectively, decreased locomotor activity. Contrarily, the chiral compounds produced excitatory effects. Increased locomotor activity was found with S-TGLU and R-TGLU at 100, 316 and 562.3 mg/kg, and S-TASP at 316 and 562.3 mg/kg. These molecules showed no activity in the EPM test or PTZ model. In the 4-AP model, however, S-TGLU (237.1, 316 and 421.7 mg/kg) as well as S-TASP and R-TASP (316 mg/kg) lowered the convulsive and death rate. Conclusion: The chiral compounds exhibited a non-competitive NMDAR antagonist profile and the non-chiral molecules possessed selective sedative properties. The NMDAR exhibited stereoselectivity for S-TGLU while it is not a preference for the aspartic derivatives. The results appear to be supported by the in silico studies, which evidenced a high affinity of phthalimides for the hNMDAR and mGluR type 1.


1995 ◽  
Vol 308 (3) ◽  
pp. 865-871 ◽  
Author(s):  
S J Milner ◽  
G L Francis ◽  
J C Wallace ◽  
B A Magee ◽  
F J Ballard

The oxidative folding of human insulin-like growth factor (IGF)-I yields two major disulphide folding isomers. In the present study, B-domain analogues of IGF-I were used to investigate the effect of mutations on the folding reaction and to investigate the functional implications of misfolding. The analogues used were substitutions of the native Glu3 by Gly or Arg, or the native Glu9 by Lys. IGF-I and these analogues were also prepared attached to a hydrophobic 13-amino-acid N-terminal extension, Met-Phe-Pro-Ala-Met-Pro-Leu-Ser-Ser-Leu-Phe-Val-Asn, referred to as ‘Long-IGF-I’ analogues. Each IGF was fully reduced and refolded to yield native and misfolded isomers, which were subsequently purified for biological characterization. Analysis of the folding reaction at equilibrium revealed a distribution of folding isomers characteristic for each peptide. The yield of the native disulphide folding isomer was increased for the Glu3 substitutions, but not for the Glu9 substitution. The main alternative folding isomer was present in the IGF-I analogues in reduced proportions. Except for [Gly3]IGF-I the N-terminal extension increased the yield of the native isomer which was maximal for the analogue Long-[Arg3]IGF-I. A folding intermediate for the latter analogue was isolated and partially characterized. The biological assays showed that all the main alternative isomers bound poorly to IGF-binding proteins (IGFBPs) secreted by L6 myoblasts. Moreover, these isomers bound to the type 1 IGF receptor with 0.5-25% the affinity of the native isomer. In a rat L6 myoblast protein-synthesis assay, the observed biological activity of the native and main alternative isomers was explained by their modified IGFBP- and receptor-binding properties. We propose that the N-terminal extension imparts a steric constraint at a crucial point in folding, thus allowing native disulphide bonds to form efficiently.


Viruses ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 508
Author(s):  
Roozbeh Tahmasebi ◽  
Antonio Charlys da Costa ◽  
Kaelan Tardy ◽  
Rory J. Tinker ◽  
Flavio Augusto de Padua Milagres ◽  
...  

Human Adenovirus species C (HAdV-C) is the most common etiologic agent of respiratory disease. In the present study, we characterized the nearly full-length genome of one potential new HAdV-C recombinant strain constituted by Penton and Fiber proteins belonging to type 89 and a chimeric Hexon protein of types 1 and 89. By using viral metagenomics techniques, we screened out, in the states of Tocantins and Pará, Northern and North regions of Brazil, from 2010 to 2016, 251 fecal samples of children between 0.5 to 2.5 years old. These children were presenting acute diarrhea not associated with common pathogens (i.e., rotavirus, norovirus). We identified two HAdV-C strains in two distinct patients. Phylogenetic analysis performed using all complete genomes available at GenBank database indicated that one strain (HAdV-C BR-245) belonged to type 1. The phylogenetic analysis also indicated that the second strain (HAdV-C BR-211) was located at the base of the clade formed by the newly HAdV-C strains type 89. Recombination analysis revealed that strain HAdV-C BR-211 is a chimera in which the variable regions of Hexon gene combined HAdV-C1 and HAdV-C89 sequences. Therefore, HAdV-C BR-211 strain possesses a genomic backbone of type HAdV-C89 and a unique insertion of HAdV-C1 in the Hexon sequence. Recombination may play an important driving force in HAdV-C diversity and evolution. Studies employing complete genomic sequencing on circulating HAdV-C strains in Brazil are needed to understand the clinical significance of the presented data.


Biomedicines ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 132
Author(s):  
Sherif T. S. Hassan

While few studies have revealed the biological properties of brassicasterol, a phytosterol, against some biological and molecular targets, it is believed that there are still many activities yet to be studied. In this work, brassicasterol exerts a therapeutic utility in an in vitro setting against herpes simplex virus type 1 (HSV-1) and Mycobacterium tuberculosis (Mtb) as well as a considerable inhibitory property against human angiotensin-converting enzyme (ACE) that plays a dynamic role in regulating blood pressure. The antireplicative effect of brassicasterol against HSV-1 is remarkably detected (50% inhibitory concentration (IC50): 1.2 µM; selectivity index (SI): 41.7), while the potency of its effect is ameliorated through the combination with standard acyclovir with proper SI (IC50: 0.7 µM; SI: 71.4). Moreover, the capacity of this compound to induce an adequate level of antituberculosis activity against all Mtb strains examined (minimum inhibitory concentration values ranging from 1.9 to 2.4 µM) is revealed. The anti-ACE effect (12.3 µg/mL; 91.2% inhibition) is also ascertained. Molecular docking analyses propose that the mechanisms by which brassicasterol induces anti-HSV-1 and anti-Mtb might be related to inhibiting vital enzymes involved in HSV-1 replication and Mtb cell wall biosynthesis. In summary, the obtained results suggest that brassicasterol might be promising for future anti-HSV-1, antituberculosis, and anti-ACE drug design.


2007 ◽  
Vol 52 (2) ◽  
pp. 655-665 ◽  
Author(s):  
Tomas Cihlar ◽  
Adrian S. Ray ◽  
Constantine G. Boojamra ◽  
Lijun Zhang ◽  
Hon Hui ◽  
...  

ABSTRACT GS-9148 [(5-(6-amino-purin-9-yl)-4-fluoro-2,5-dihydro-furan-2-yloxymethyl)phosphonic acid] is a novel ribose-modified human immunodeficiency virus type 1 (HIV-1) nucleotide reverse transcriptase (RT) inhibitor (NRTI) selected from a series of nucleoside phosphonate analogs for its favorable in vitro biological properties including (i) a low potential for mitochondrial toxicity, (ii) a minimal cytotoxicity in renal proximal tubule cells and other cell types, (iii) synergy in combination with other antiretrovirals, and (iv) a unique resistance profile against multiple NRTI-resistant HIV-1 strains. Notably, antiviral resistance analysis indicated that neither the K65R, L74V, or M184V RT mutation nor their combinations had any effect on the antiretroviral activity of GS-9148. Viruses carrying four or more thymidine analog mutations showed a substantially smaller change in GS-9148 activity relative to that observed with most marketed NRTIs. GS-9131, an ethylalaninyl phosphonoamidate prodrug designed to maximize the intracellular delivery of GS-9148, is a potent inhibitor of multiple subtypes of HIV-1 clinical isolates, with a mean 50% effective concentration of 37 nM. Inside cells, GS-9131 is readily hydrolyzed to GS-9148, which is further phosphorylated to its active diphosphate metabolite (A. S. Ray, J. E. Vela, C. G. Boojamra, L. Zhang, H. Hui, C. Callebaut, K. Stray, K.-Y. Lin, Y. Gao, R. L. Mackman, and T. Cihlar, Antimicrob. Agents Chemother. 52:648-654, 2008). GS-9148 diphosphate acts as a competitive inhibitor of RT with respect to dATP (Ki = 0.8 μM) and exhibits low inhibitory potency against host polymerases including DNA polymerase γ. Oral administration of GS-9131 to beagle dogs at a dose of 3 mg/kg of body weight resulted in high and persistent levels of GS-9148 diphosphate in peripheral blood mononuclear cells (with a maximum intracellular concentration of >9 μM and a half-life of >24 h). This favorable preclinical profile makes GS-9131 an attractive clinical development candidate for the treatment of patients infected with NRTI-resistant HIV.


1995 ◽  
Vol 11 (2) ◽  
pp. 239-248 ◽  
Author(s):  
PING ZHONG ◽  
MARTINE PEETERS ◽  
WOUTER JANSSENS ◽  
KATRIEN FRANSEN ◽  
LEO HEYNDRICKX ◽  
...  

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