Molusco contagioso del párpado: manifestación cutánea de inmunosupresión / Eyelid molluscum contagiosum: Cutaneous manifestation of immunosuppression

Resumen El molusco contagioso es una infección viral cutánea, usualmente benigna y autolimitada, causada por un virus del género Molluscipoxvirus. Es más frecuente en niños, adultos jóvenes sexualmente activos e inmunosuprimidos. La lesión clínica característica es una pápula umbilicada eucrómica o de tono perlado, que se disemina rápidamente y puede afectar cualquier superficie muco-cutánea, aunque la localización en los párpados es atípica. Se presentan dos casos de pacientes jóvenes inmunosuprimidos, con moluscos contagiosos palpebrales, en quienes el diagnóstico clínico inicial fue incorrecto. Se enfatiza la importancia de diagnosti car oportunamente las lesiones papulares que afectan la piel del párpado ya que la presencia de molusco contagioso en esta zona se considera una manifestación cutánea de inmunosupresión.

Abstract Molluscum contagiosum is a cutaneous viral infection, usually benign and self-limited, caused by the molluscum contagiosum virus, of the genus Molluscipoxvirus. It is more common in pediatric population, sexually active young people and immunosuppressed patients. Clinical presentation is characterized by umbilicated white to flesh-colored or pearly papules, which rapidly spread and can affect any muco-cutaneous membrane. Although the eyelid presentation is atypical, we herein present two young, immunosuppressed patients, with diagnosis of palpebral molluscum contagiosum, in which the initial clinical diagnosis was wrong. We emphasize the importance in making a timely diagnosis of papular lesions localized on the eyelids and the correlation of these lesions as a cutaneous manifestation of immunosuppression.

Dephosphorylation of cGAS by PPP6C impairs its substrate binding activity and innate antiviral response

The cyclic GMP-AMP (cGAMP) synthase (cGAS) plays a critical role in host defense by sensing cytosolic DNA derived from microbial pathogens or mis-located cellular DNA. Upon DNA binding, cGAS utilizes GTP and ATP as substrates to synthesize cGAMP, leading to MITA-mediated innate immune response. In this study, we identified the phosphatase PPP6C as a negative regulator of cGAS-mediated innate immune response. PPP6C is constitutively associated with cGAS in un-stimulated cells. DNA virus infection causes rapid disassociation of PPP6C from cGAS, resulting in phosphorylation of human cGAS S435 or mouse cGAS S420 in its catalytic pocket. Mutation of this serine residue of cGAS impairs its ability to synthesize cGAMP upon DNA virus infection. In vitro experiments indicate that S420-phosphorylated mcGAS has higher affinity to GTP and enzymatic activity. PPP6C-deficiency promotes innate immune response to DNA virus in various cells. Our findings suggest that PPP6C-mediated dephosphorylation of a catalytic pocket serine residue of cGAS impairs its substrate binding activity and innate immune response, which provides a mechanism for keeping the DNA sensor cGAS inactive in the absence of infection to avoid autoimmune response.

Dephosphorylation of cGAS by PPP6C impairs its substrate binding activity and innate antiviral response

The cyclic GMP-AMP (cGAMP) synthase (cGAS) plays a critical role in host defense by sensing cytosolic DNA derived from microbial pathogens or mis-located cellular DNA. Upon DNA binding, cGAS utilizes GTP and ATP as substrates to synthesize cGAMP, leading to MITA-mediated innate immune response. In this study, we identified the phosphatase PPP6C as a negative regulator of cGAS-mediated innate immune response. PPP6C is constitutively associated with cGAS in un-stimulated cells. DNA virus infection causes rapid disassociation of PPP6C from cGAS, resulting in phosphorylation of human cGAS S435 or mouse cGAS S420 in its catalytic pocket. Mutation of this serine residue of cGAS impairs its ability to synthesize cGAMP upon DNA virus infection. In vitro experiments indicate that S420-phosphorylated mcGAS has higher affinity to GTP and enzymatic activity. PPP6C-deficiency promotes innate immune response to DNA virus in various cells. Our findings suggest that PPP6C-mediated dephosphorylation of a catalytic pocket serine residue of cGAS impairs its substrate binding activity and innate immune response, which provides a mechanism for keeping the DNA sensor cGAS inactive in the absence of infection to avoid autoimmune response.

Cloning and high-level expression of Thermus thermophilus RecA in E. coli: purification and novel use in HBV diagnostics

ABSTRACT We studied the role of Thermus thermophilus Recombinase A (RecA) in enhancing the PCR signals of DNA viruses such as Hepatitis B virus (HBV). The RecA gene of a thermophilic eubacterial strain, T. thermophilus, was cloned and hyperexpressed in Escherichia coli. The recombinant RecA protein was purified using a single heat treatment step without the use of any chromatography steps, and the purified protein (>95%) was found to be active. The purified RecA could enhance the polymerase chain reaction (PCR) signals of HBV and improve the detection limit of the HBV diagnosis by real time PCR. The yield of recombinant RecA was ∼35 mg/L, the highest yield reported for a recombinant RecA to date. RecA can be successfully employed to enhance detection sensitivity for the diagnosis of DNA viruses such as HBV, and this methodology could be particularly useful for clinical samples with HBV viral loads of less than 10 IU/mL, which is interesting and novel.

Identification of circo-like virus-Brazil genomic sequences in raw sewage from the metropolitan area of São Paulo: evidence of circulation two and three years after the first detection

BACKGROUND Two novel viruses named circo-like virus-Brazil (CLV-BR) hs1 and hs2 were previously discovered in a Brazilian human fecal sample through metagenomics. CLV-BR hs1 and hs2 possess a small circular DNA genome encoding a replication initiator protein (Rep), and the two genomes exhibit 92% nucleotide identity with each other. Phylogenetic analysis based on the Rep protein showed that CLV-BRs do not cluster with circoviruses, nanoviruses, geminiviruses or cycloviruses. OBJECTIVE The aim of this study was to search for CLV-BR genomes in sewage and reclaimed water samples from the metropolitan area of São Paulo, Brazil, to verify whether the first detection of these viruses was an isolated finding. METHODS Sewage and reclaimed water samples collected concomitantly during the years 2005-2006 were purified and concentrated using methodologies designed for the study of viruses. A total of 177 treated reclaimed water samples were grouped into five pools, as were 177 treated raw sewage samples. Nucleic acid extraction, polymerase chain reaction (PCR) amplification and Sanger sequencing were then performed.e FINDINGS CLV-BR genomes were detected in two pools of sewage samples, p6 and p9. Approximately 28% and 51% of the CLV-BR genome was amplified from p6 and p9, respectively, including 76% of the Rep gene. The detected genomes are most likely related to CLV-BR hs1. Comparative analysis showed several synonymous substitutions within Rep-encoding sequences, suggesting purifying selection for this gene, as has been observed for other eukaryotic circular Rep-encoding single-stranded DNA (CRESS-DNA) viruses. MAIN CONCLUSION The results therefore indicated that CLV-BR has continued to circulate in Brazil two and three years after first being detected.

Early HHV-6 replication is associated with morbidity non-related to CMV infection after kidney transplantation

Human herpesvirus type 6-(HHV-6) has been associated with morbidity after liver transplantation. OBJECTIVE: The aim of this study was to determine the HHV-6 seroprevalence among donor-recipient pairs, analyze the incidence of early active infection, its clinical manifestation, interaction with CMV, and the related morbidity in the first year after kidney transplantation. METHODS: 46 donor-recipient pairs had IgG evaluated by ELISA before transplantation: HHV-6(Pambio - USA) and CMV-(Roche - USA). A frozen whole blood sample collected weekly (from the 1st to the 6th week) was retrospectively tested for HHV-6 viral load (VL) determination by real time quantitative PCR (qPCR, Nanogen - Italy). Patients were preemptively surveyed for CMV by pp65 antigenemia (Ag, APAAP, immunohistochemistry, Biotest - Germany) from the 4th to the 12th week after transplantation. Active infection was defined as qPCR-HHV6+ (viral-load/mL-VL) and Ag+ (+cells/100.000 granulocytes), for HHV-6 and CMV, respectively. DCMV was defined as simultaneous positive antigenemia and suggestive signs/symptoms. Concerning +qPCR-HHV6, associated factors, clinical manifestation, interaction with CMV and morbidity were searched. RESULTS: Pre-transplant HHV-6 seroprevalence was significantly higher among kidney recipients compared to their donors (82.6x54.8%; p = 0.005 [3.9 (1.4-10.4)]). Active infection by this virus occurred in 26.1% (12/46), with no association with previous IgG (p = 0.412). Median VL was 125 copies/mL (53-11.264), and the median Ag was 21 +cells (2-740). There was no association between HHV-6 and CMV activation after transplantation (p = 0.441), neither concerning DCMV (p = 0.596). Median highest Ag+ and days of ganciclovir treatment were similar between qPCR-HHV6 + or - (p = 0.206 and p = 0.124, respectively). qPCR-HHV6+ was associated with higher incidence of bacterial (p = 0.009) and fungal (p = 0.001) infections, and higher number (p = 0.001) of hospital admission and longer duration of hospitalization over the first 6 and 12 months post-transplantation (p = 0.033 and p = 0.001). CONCLUSION: Latent HHV-6 infection is more common among recipients than donors before transplantation. Early active infection by this pathogen after transplantation does not increase DCMV incidence or severity during the first 3 months of follow-up. However, early HHV-6 replication is associated with other infections and hospitalizations in the first year.

Antiviral activity of the Lippia graveolens (Mexican oregano) essential oil and its main compound carvacrol against human and animal viruses

Mexican oregano (Lippia graveolens) is a plant found in Mexico and Central America that is traditionally used as a medicinal herb. In the present study, we investigated the antiviral activity of the essential oil of Mexican oregano and its major component, carvacrol, against different human and animal viruses. The MTT test (3-4,5-dimethythiazol-2yl)-2,5-diphenyl tetrazolium bromide) was conducted to determine the selectivity index (SI) of the essential oil, which was equal to 13.1, 7.4, 10.8, 9.7, and 7.2 for acyclovir-resistant herpes simplex virus type 1 (ACVR-HHV-1), acyclovir-sensitive HHV-1, human respiratory syncytial virus (HRSV), bovine herpesvirus type 2 (BoHV-2), and bovine viral diarrhoea virus (BVDV), respectively. The human rotavirus (RV) and BoHV-1 and 5 were not inhibited by the essential oil. Carvacrol alone exhibited high antiviral activity against RV with a SI of 33, but it was less efficient than the oil for the other viruses. Thus, Mexican oregano oil and its main component, carvacrol, are able to inhibit different human and animal viruses in vitro. Specifically, the antiviral effects of Mexican oregano oil on ACVR-HHV-1 and HRSV and of carvacrol on RV justify more detailed studies.

Predictors of virological response in HBeAg-positive chronic hepatitis B patients treated with adefovir dipivoxil / 中华传染病杂志

Objective To investigate the predictive factors of virological response in HBeAg-positive chronic hepatitis B (CHB)patients treated with adefovir dipivoxil (ADV).Methods A total of 203 HBeAg-positive CHB patients treated with ADV (Mingzheng)10 mg once daily for 48 weeks were recruited.The gene polymorphisms at positions-238 and-308 in tumor necrosis factor (TNF)-α promoter region were determined by the restriction fragment length polymorphism assay of products amplified using polymerase chain reaction (PCR-RFLP).The serum levels of TNF-a at baseline were measured by enzyme linked immunosorbent assay (ELISA).Hepatitis B virus (HBV)genotypes were tested by real-time fluorescent quantitative PCR and HBV subgenotypes were tested by HBV S gene sequencing.Factors related to ADV response were determined by Logistic regression analysis.Results The HBV DNA negative rate,alanine aminotransferase (ALT)normalization rate,HBeAg loss rate and seroconversion rate,and combined response rate at week 24 and 48 of treatment in 203 patients were 31.5% (64/203),59.1% (120/203),15.8% (32/203),8.9% (18/203),13.3% (27/203)and 58.6% (119/203),78.3% (159/203),29.6% (60/203),16.7% (34/203),25.6% (52/203),respectively.HBV DNA negative rate at week 24 was higher in patients with HBV genotype B,that was higher in patients with TNF-α-308G/A genotype,and that was higher in patients with higher baseline ALT level or lower baseline HBV DNA level [OR = 0.405,95 % CI (0.191 - 0.859),P =0.019;OR=0.292,95%CI(0.132-0.643),P=0.002;OR=0.933,95%CI(0.989-0.997),P＜0.01 ;OR=2.089,95%CI (1.412-3.092),P＜0.01].Meanwhile,HBV DNA negative rate at week 48 were higher in patients with higher HBV DNA negative rate at week 24 or higher baseline ALT level [OR=0.029,95%CI(0.007-0.126),P＜0.01;OR= 0.995,95%CI(0.991-0.999),P=0.016].Conclusions HBV genotype,TNF-α-308 genotype,baseline levels of ALT and HBV DNA are predictors of virological response at week 24 in HBeAg-positive CHB patients treated with ADV.And the HBV DNA negative rate at week 24 and baseline ALT level are predictors of virological response at week 48.

The correlation and clinical significance of HBV infection makers / 中国基层医药

Objective To explore the internal relations of HBV markers and its clinical significance.Methods HBV Pre S1-Ag、HBV-M(HBsAg、HBsAb、HBeAg、HBeAb、HBcAb)and HBV DNA of 106 patients were detected by ELISA and FQ-PCR respectively.Results The total positive rates of Pre-S1 antigen and HBV DNA in 106 cases were 81.1%and 84.9%respectively.In41 HBeAg-positive cases.Pre S1-Ag and HBV DNA detection rate was 95.1%.90.2%.And HBeAg-negative 2 groups Pre S1-Ag and HBV DNA detection rate was also higher.Conclusion HBV Per S1-Ag Was a very valuable serum marker in terms of direct HBV replication alone can not HBeAg-positive to determine whether the replication of the virus.

Effects of postopertive anti-viral therapy using adefovir dipivoxil on recurrence of hepatocellular carcinoma with HBV infection / 国际外科学杂志

Objective To investigate the effect of postoperative anti-viral therapy using adefovir dipivoxil in recurrence of hepatocellular carcinoma HCC with HBV infection. Methods Sixty HCC patients with HBV infection were randomized into two groups:Group A (n=23) received hepatectomy only, and Group B (n=37) received hepatectomy and postoperative therapy using adefovir dipivoxil. The changes in liver func-tion, the suppression of HBV-DNA, HBeAg seroconversion rate, tumor recurrence rate and median survival in the two groups were observed and compared. Results In Group B, serum albumin, total bilirubin, AST and ALT were significantly improved compared with Group A (P < 0.05). Furthermore, the rate of 6-month and 1-year HBV-DNA suppression, the rate of 6-month and 1-year HBeAg seroconversion were significantly improved compared with Group A (P < 0.05). In Group A and Group B the tumor recurrence rate was 82. 6% (19/23) vs 78.4% (29/37) (P > 0.05), the recurrence time was 7.3 vs9.6 months (P > 0.05) and the median survival time was 17.4 vs 24.9 months (P < 0.01). Conclusion The results suggest that an-ti-viral therapy using adefovir dipivoxil postoperatively may improve the remnant liver function, suppress the HBV reaction, prolong the survival for patients with HCC with HBV infection.

Effect of methylene blue and visible light monitored by flurescence quantitative PCR on the inactivation of plasma hepatitis B virus / 国际检验医学杂志

Objective To evaluate the effect of methylene blue and visible light by FQ-PCR assay on the inactivation of plasma hepatitis B virus,and to establish a direct and impersonal basis for the surveillance of cural inactivation.Methods Four samples of plasma of HBV-DNA positive were added with methylene blue. Then the plasma was processed with visible light radiation(30 000 Lux) for 0, 5, 10, 15,30 min respectively. Moreover,the concentration of HBV-DNA samples was quantitatively detected by the method of FQ-PCR and compared with untreated samples to evaluate the effect of HBV inactivation and its relationship with the time of radiation.Results The original concentration of HBV-DNA was 5.6?107, 3.2?106, 1.8?106,3.5?105 copies/ml respectively. After being added with methyene blue, the concentration of HBV-DNA was significantly decreased(P

Gene quasispecies analysis of transfusion transmitted virus DNA in two patients with transfusion transmitted virus infection / 中国医师杂志

Objective To investigate gene variation and the relationship between gene variation and pathogenicity of transfusion transmitted virus(TTV).Methods The TTV DNA in the serum sample from a blood donor(BD) and a chronic non-A-G severe hepatitis(CSH) patient with TTV infection was amplified by using PCR.The purified PCR product was cloned and 10 clones from each case were sequenced.The sequences were compared among different clones and analyzed by Phylogentic tree.Results There were two different TTV strains in the BD and seven different TTV strains in the chronic non-A-G severe hepatitis patient.The TTV clones in the BD were of G1a subtype and those of the CSH were of G1a and G1b subtype.Conclusion Gene variant of TTV was much more complicated in the CSH patients than that in the BD ones.

Is the so-called "immune" reaction to smallpox vaccination a misnomer?

1. Vaccine virus, either potent or heated, can produce reactions which may be described as immediate or immune2. The morphologic characteristics of the reactions are the same in both potent and heated vaccines; 3. While those produced by heated vaccine tend to regress beginning the 3rd day and completely disappear by the 6th day after vaccination, those produced by potent vaccine continue to develop to their maximum intensity until about the 10th day; and4. Areolo-vesicular reactions with cloudy fluid inside the vesicles are also produced by heated inactivated virus as early as 24 hours after vaccination. (Conclusion)

Vigilance against smallpox --- a constant need

The threat of smallpox to the Philippines is real. It is evident that quarantine measures alone, no matter how strictly implemented, cannot provide any absolute protection against the chances of a smallpox flare-up in this country. Nothing short of isolating all incoming passengers for 14 days can do this. Even so, such a drastic action will not take care of those who sneak into our shores from infected areas. It may be restating the obvious, but it can never be emphasized enough that only the continuous maintenance of an immune population can constitute the stronger bulwark against such a scourge. And, as I have already mentioned, immunity should cover at least 80% of the population. The big question arises: How adequately can we come up to such levels of protection for our country? The answer to this depends upon the full cooperation not only of those in the public health service but also of all medical men together with an enlightened public. (Conclusion)