Antiviral and immunoregulatory effects of curcumin on coxsackievirus B3-infected hepatitis

Fulminant hepatitis is a life-threatening complication of coxsackievirus B (CVB) 3 infections. The condition may deteriorate to disseminated intravascular coagulopathy with markedly increased liver enzymes, inflammatory cytokines, and chemokines, which significantly induce local and systemic inflammation. Curcumin exhibits anti-inflammatory and antiviral characteristics in inflammatory and infectious diseases. Here we determined effects of curcumin on viral replications, cytokine and chemokine expressions, and liver damage in CVB3-infected Huh-7 cells. The mouse-adapted CVB3 strain was used to investigate the antiviral and anti-inflammatory effects of curcumin on CVB3-induced hepatitis in a mouse model. In vitro studies showed that curcumin reduced viral protein and titer levels and increased cell viability. Curcumin enhanced the heme oxygenase-1 (HO-1) protein level and decreased the levels of cleaved caspase-3 protein and mRNA of gene encoding C-X-C motif chemokine 10 in infected cells. In vivo studies showed that curcumin improved the survival rate and clinical scores in mice and reduced the viral titer in the liver during CVB3 infection. Moreover, the HO-1 levels were increased, and the cleaved caspase-3 levels were diminished in the CVB3-infected liver. Curcumin reduced the levels of interferon (IFN)-γ and monokine induced by IFN-γ in liver and levels of interleukin (IL)-8 in serum, but increased levels of regulated activation, normal T cell expression in liver and levels of IL-10 in serum of CVB3-infected mice. In summary, curcumin presents antiviral and anti-inflammation efficacies in CVB3 infection in vitro and in vivo; these results provide potential evidence on the feasibility of curcumin for clinical treatment.

Highly-specific aptamer targeting SARS-CoV-2 S1 protein screened on an automatic integrated microfluidic system for COVID-19 diagnosis

Variants of the severe acute respiratory syndrome coronavirus (SARS-CoV-2) have evolved such that it may be challenging for diagnosis and clinical treatment of the pandemic coronavirus disease-19 (COVID-19). Compared with developed SARS-CoV-2 diagnostic tools recently, aptamers may exhibit some advantages, including high specificity/affinity, longer shelf life (vs. antibodies), and could be easily prepared. Herein an integrated microfluidic system was developed to automatically carry out one novel screening process based on the systematic evolution of ligands by exponential enrichment (SELEX) for screening aptamers specific with SARS-CoV-2. The new screening process started with five rounds of positive selection (with the S1 protein of SARS-CoV-2). In addition, including non-target viruses (influenza A and B), human respiratory tract-related cancer cells (adenocarcinoma human alveolar basal epithelial cells and dysplastic oral keratinocytes), and upper respiratory tract-related infectious bacteria (including methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae), and human saliva were involved to increase the specificity of the screened aptamer during the negative selection. Totally, all 10 rounds could be completed within 20 h. The dissociation constant of the selected aptamer was determined to be 63.0 nM with S1 protein. Limits of detection for Wuhan and Omicron clinical strains were found to be satisfactory for clinical applications (i.e. 4.80 × 10¹ and 1.95 × 10² copies/mL, respectively). Moreover, the developed aptamer was verified to be capable of capturing inactivated SARS-CoV-2 viruses, eight SARS-CoV-2 pseudo-viruses, and clinical isolates of SARS-CoV-2 viruses. For high-variable emerging viruses, this developed integrated microfluidic system can be used to rapidly select highly-specific aptamers based on the novel SELEX methods to deal with infectious diseases in the future.

Acyclovir-resistant HSV-1 isolates among immunocompromised patients in southern Taiwan: Low prevalence and novel mutations

Herpes simplex virus type 1 (HSV-1) can establish latency in humans and easily relapse in immunocompromised patients, with significant mortality. Treatment with acyclovir (ACV) can result in the emergence of HSV resistance. A total of 440 frozen HSV-1 isolates collected from 318 patients from January 2014 to July 2019 were obtained from National Cheng Kung University Hospital in southern Taiwan. These 440 isolates were subjected to phenotypic studies for ACV-resistance by initial screening with the plaque reduction assay (PRA) and further validation by the DNA reduction assay (DRA). The ACV-resistant strains were further investigated by Sanger sequencing for the full-length UL23 and UL30 genes, which encode thymidine kinase and DNA polymerase, respectively. Hematological malignancies or hematopoietic stem-cell transplantation patients accounted for 56.9% (124/218) among the immunocompromised patients (218/318) in this study. Repeated sampling for HSV testing was 50% (109/218) in immunocompromised patients. Only 1.38% (3/218) of immunocompromised patients and 0.9% (3/318) of all patients developed ACV-resistant HSV-1 as measured by phenotypic screening assays. It is noteworthy that a novel Y248D mutation in the UL23 gene from an immunocompromised patient was found by both PRA and DRA. In 3D protein predicting analysis, uncharged Y248 was located at an alpha-helix and substituted by negative-charged D248, which may alter the function of viral thymidine kinase. Besides, three unreported mutations related to natural polymorphism were found in virus isolates from two immunocompetent patients, including 683-688 deletion, R227H, and A351D in the UL30 gene. These data show that the prevalence of ACV-resistant HSV-1 among immunocompromised patients in southern Taiwan is low. These results will be helpful for the clinical management and treatment of HSV infections.

Novel Software for High-level Virological Testing: Self-Designed Immersive Virtual Reality Training Approach

BACKGROUND

To ensure the timely diagnosis of emerging infectious diseases, high-tech molecular biotechnology is often used to detect pathogens and has gradually become the gold standard for virological testing. However, beginners and students are often unable to practice their skills due to the higher costs associated with high-level virological testing, the increasing complexity of the equipment, and the limited number of specimens from patients. Therefore, a new training program is necessary to increase training and reduce the risk of test failure.

OBJECTIVE

The aim of the study is to (1) develop and implement a virtual reality (VR) software for simulated and interactive high-level virological testing that can be applied in clinical practice and skills building or training settings and (2) evaluate the VR simulation's effectiveness on reaction, learning, and behavior of the students (trainees).

METHODS

Viral nucleic acid tests on a BD MAX instrument were selected for our VR project because it is a high-tech automatic detection system. There was cooperation between teachers of medical technology and biomedical engineering. Medical technology teachers were responsible for designing the lesson plan, and the biomedical engineering personnel developed the VR software. We designed a novel VR teaching software to simulate cognitive learning via various procedure scenarios and interactive models. The VR software contains 2D VR "cognitive test and learning" lessons and 3D VR "practical skills training" lessons. We evaluated students' learning effectiveness pre- and posttraining and then recorded their behavior patterns when answering questions, performing repeated exercises, and engaging in clinical practice.

RESULTS

The results showed that the use of the VR software met participants' needs and enhanced their interest in learning. The average posttraining scores of participants exposed to 2D and 3D VR training were significantly higher than participants who were exposed solely to traditional demonstration teaching (P<.001). Behavioral assessments of students pre- and posttraining showed that students exposed to VR-based training to acquire relevant knowledge of advanced virological testing exhibited significantly improved knowledge of specific items posttraining (P<.01). A higher participant score led to fewer attempts when responding to each item in a matching task. Thus, VR can enhance students' understanding of difficult topics.

CONCLUSIONS

The VR program designed for this study can reduce the costs associated with virological testing training, thus, increasing their accessibility for students and beginners. It can also reduce the risk of viral infections particularly during disease outbreaks (eg, the COVID-19 pandemic) and also enhance students' learning motivation to strengthen their practical skills.

Characteristics of rectal chlamydia among men who have sex with men in southern Taiwan, 2020-2022: An emerging threat of rectal lymphogranuloma venereum L2b

BACKGROUND

The prevalence of rectal chlamydia among men who have sex with men (MSM) without human deficiency virus infection (non-HIV) remains uncertain in Taiwan, and rectal lymphogranuloma venereum (LGV) among MSM has never been reported in the Far East.

MATERIAL AND METHODS

From January 2020 to April 2022, MSM coming for anonymous voluntary counseling and testing, for pre-exposure prophylaxis, and for antiretroviral therapy were enrolled. All participants submitted his fecal samples and completed a QR-code questionnaire. Medical records of those who took regular medical visits for HIV were recorded. Multiplex polymerase chain reaction (PCR) was performed for all fecal samples, and ompA gene sequencing was therefore performed for each Chlamydia-positive fecal sample.

RESULTS

Among 341 MSM during 2020-2022 in southern Taiwan, 21 (6.2%) had rectal chlamydia infection. Risk factors of rectal chlamydia included co-infection with rectal gonorrhea (adjusted odds ratio [AOR] 6.78, 95% confidence interval [CI] 1.44-31.91, P = 0.015) and multiple sexual partners (AOR 1.373, 95% CI 1.002-1.882, P = 0.048). Further ompA gene sequencing from 19 Chlamydia-positive fecal samples revealed that the prevalent genotypes or genovariants were Da (26.3%) and L2b (26.3%), followed by B (21.1%), J (14.3%), and G (9.5%). All cases of rectal LGV genovariant L2b presented as acute proctitis with diarrhea, anal pain, or discharge and were treated successfully with prolonged treatment of doxycycline.

CONCLUSIONS

Rectal gonorrhea and multiple sexual partners are risk factors for rectal chlamydia. Clinicians in Taiwan should be aware of the emerging threat of rectal LGV among MSM with acute proctitis.

RNA Interference Approach Is a Good Strategy against SARS-CoV-2

COVID-19, caused by SARS-CoV-2, created a devastating outbreak worldwide and consequently became a global health concern. However, no verifiable, specifically targeted treatment has been devised for COVID-19. Several emerging vaccines have been used, but protection has not been satisfactory. The complex genetic composition and high mutation frequency of SARS-CoV-2 have caused an uncertain vaccine response. Small interfering RNA (siRNA)-based therapy is an efficient strategy to control various infectious diseases employing post-transcriptional gene silencing through the silencing of target complementary mRNA. Here, we designed two highly effective shRNAs targeting the conserved region of RNA-dependent RNA polymerase (RdRP) and spike proteins capable of significant SARS-CoV-2 replication suppression. The efficacy of this approach suggested that the rapid development of an shRNA-based therapeutic strategy might prove to be highly effective in treating COVID-19. However, it needs further clinical trials.

Outbreak of respiratory syncytial virus subtype ON1 among children during COVID-19 pandemic in Southern Taiwan

BACKGROUND

The regional respiratory syncytial virus (RSV) outbreak in southern Taiwan in late 2020 followed the surge of RSV cases in the national surveillance data and displayed distinct clinical features. This study investigated RSV epidemiology in the most recent five years and compared the clinical manifestations of this outbreak with non-outbreak period.

METHODS

Medical records of RSV-infected children at the National Cheng Kung University Hospital from January 2016 to December 2020 were retrospectively retrieved from hospital-based electronic medical database. Cases of RSV infection were identified by RSV antigen positive and/or RSV isolated from respiratory specimens. The demographic, clinical presentations, and laboratory data were recorded. The RSV isolates in 2020 was sequenced for phylogenetic analysis.

RESULTS

Overall, 442 RSV-infected cases were retrieved and 42.1% (186 cases) clustered in late 2020. The 2020 outbreak started in September, peaked in November, and lasted for 3 months. 2020 RSV-infected children were older (2.3 ± 2.2 years vs. 1.0 ± 1.0 years), more likely to be diagnosed with bronchopneumonia (57.5% vs. 31.6%), but also had a lower hospitalization rate, shorter hospital stay, less oxygen use, and less respiratory distress than those in 2016-2019 (all p value < 0.05). The RSV isolates in 2020 belonged to RSV-A subtype ON1 but were phylogenetically distinct from the ON1 strains prevalent in Taiwan previously.

CONCLUSION

The 2020 RSV outbreak was led by the novel RSV-A subtype ON1 variant with clinical manifestations distinct from previous years. Continuous surveillance of new emerging variants of respiratory viruses in the post-pandemic era is warranted.

Therapeutics for fulminant hepatitis caused by enteroviruses in neonates

Neonatal infection with nonpolio enteroviruses (EVs) causes nonspecific febrile illnesses and even life-threatening multiorgan failure. Hepatitis, which often results in hepatic necrosis followed by disseminated intravascular coagulopathy, is one of the most severe and frequent fatal neonatal EV infection complications. Coxsackievirus B (CVB) 1–5 and many echoviruses have been most commonly identified. Neonatal EV infection treatment has usually involved initial supportive care. Studies for CVB and echovirus infection treatments were developed for more than thirty years. Intravenous immunoglobulin and pleconaril therapy was performed in some clinical trials. Additionally, other studies demonstrated antiviral and/or anti-inflammatory pathogenesis mechanisms of neonatal EV hepatitis in in vitro or in vivo models. These treatments represented promising options for the clinical practice of neonatal EV hepatitis. However, further investigation is needed to elucidate the whole therapeutic potential and safety problems.

Genetic and Cross Neutralization Analyses of Coxsackievirus A16 Circulating in Taiwan from 1998 to 2021 Suggest Dominant Genotype B1 can Serve as Vaccine Candidate

Coxsackievirus A16 (CVA16) is well known for causing hand-foot-and-mouth disease (HFMD) and outbreaks were frequently reported in Taiwan in the past twenty years. The epidemiology and genetic variations of CVA16 in Taiwan from 1998 to 2021 were analyzed in this study. CVA16 infections usually occurred in early summer and early winter, and showed increased incidence in 1998, 2000-2003, 2005, 2007-2008, and 2010 in Taiwan. Little or no CVA16 was detected from 2017 to 2021. CVA16 infection was prevalent in patients between 1 to 3 years old. A total of 69 isolates were sequenced. Phylogenetic analysis based on the VP1 region showed that CVA16 subgenotype B1 was dominantly isolated in Taiwan from 1998 to 2019, and B2 was identified only from isolates collected in 1999 and 2000. There was a high frequency of synonymous mutations in the amino acid sequences of the VP1 region among CVA16 isolates, with the exception of position 145 which showed positive selection. The recombination analysis of the whole genome of CVA16 isolates indicated that the 5'-untranslated region and the non-structural protein region of CVA16 subgenotype B1 were recombined with Coxsackievirus A4 (CVA4) and enterovirus A71 (EVA71) genotype A, respectively. The recombination pattern of subgenotype B2 was similar to B1, however, the 3D region was similar to EVA71 genotype B. Cross-neutralization among CVA16 showed that mouse antisera from various subgenotypes viruses can cross-neutralize different genotype with high neutralizing antibody titers. These results suggest that the dominant CVA16 genotype B1 can serve as a vaccine candidate for CVA16.

Electromagnetically-driven integrated microfluidic platform using reverse transcription loop-mediated isothermal amplification for detection of severe acute respiratory syndrome coronavirus 2

Rapid, sensitive and accurate diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is of great need for effective quarantining and treatment. Real-time reverse-transcription polymerase chain reaction requiring thermocyling has been commonly used for diagnosis of SARS-CoV-2 though it may take two to 4 h before lengthy sample pretreatment process and require bulky apparatus and well-trained personnel. Since multiple reverse transcription loop-mediated isothermal amplification (multiple RT-LAMP) process without thermocycling is sensitive, specific and fast, an electromagnetically-driven microfluidic chip (EMC) was developed herein to lyse SARS-CoV-2 viruses, extract their RNAs, and perform qualitative analysis of three marker genes by on-chip multiple RT-LAMP in an automatic format within 82 min at a limit of detection of only ∼5000 copies per reaction (i.e. 200 virus/ μL). This compact EMC may be especially promising for SARS-CoV-2 diagnostics in resource-limited countries.

Impact of Intrahost NS5 Nucleotide Variations on Dengue Virus Replication

Due to the nature of RNA viruses, their high mutation rates produce a population of closely related but genetically diverse viruses, termed quasispecies. To determine the role of quasispecies in DENV disease severity, 22 isolates (10 from mild cases, 12 from fatal cases) were obtained, amplified, and sequenced with Next Generation Sequencing using the Illumina MiSeq platform. Using variation calling, unique wildtype nucleotide positions were selected and analyzed for variant nucleotides between mild and fatal cases. The analysis of variant nucleotides between mild and fatal cases showed 6 positions with a significant difference of p < 0.05 with 1 position in the structural region, and 5 positions in the non-structural (NS) regions. All variations were found to have a higher percentage in fatal cases. To further investigate the genetic changes that affect the virus’s properties, reverse genetics (rg) viruses containing substitutions with the variations were generated and viral growth properties were examined. We found that the virus variant rgNS5-T7812G (G81G) had higher replication rates in both Baby hamster kidney cells (BHK-21) and Vero cells while rgNS5-C9420A (A617A) had a higher replication rate only in BHK-21 cells compared to wildtype virus. Both variants were considered temperature sensitive whereby the viral titers of the variants were relatively lower at 39°C, but was higher at 35 and 37°C. Additionally, the variants were thermally stable compared to wildtype at temperatures of 29, 37, and 39°C. In conclusion, viral quasispecies found in isolates from the 2015 DENV epidemic, resulted in variations with significant difference between mild and fatal cases. These variations, NS5-T7812G (G81G) and NS5-C9420A (A617A), affect viral properties which may play a role in the virulence of DENV.

An integrated microfluidic platform featuring real-time reverse transcription loop-mediated isothermal amplification for detection of COVID-19

An integrated microfluidic platform (IMP) utilizing real-time reverse-transcription loop-mediated isothermal amplification (RT-LAMP) was developed here for detection and quantification of three genes of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; i.e., coronavirus diseases 2019 (COVID-19)): RNA-dependent RNA polymerase, the envelope gene, and the nucleocapsid gene for molecular diagnosis. The IMP comprised a microfluidic chip, a temperature control module, a fluidic control module that collectively carried out viral lysis, RNA extraction, RT-LAMP, and the real-time detection within 90 min in an automatic format. A limit of detection of 5 × 10³ copies/reaction for each gene was determined with three samples including synthesized RNAs, inactive viruses, and RNAs extracted from clinical samples; this compact platform could be a useful tool for COVID-19 diagnostics.

An integrated microfluidic platform featuring real-time reverse transcription loop-mediated isothermal amplification for detection of COVID-19

An integrated microfluidic platform (IMP) utilizing real-time reverse-transcription loop-mediated isothermal amplification (RT-LAMP) was developed here for detection and quantification of three genes of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; i.e., coronavirus diseases 2019 (COVID-19)): RNA-dependent RNA polymerase, the envelope gene, and the nucleocapsid gene for molecular diagnosis. The IMP comprised a microfluidic chip, a temperature control module, a fluidic control module that collectively carried out viral lysis, RNA extraction, RT-LAMP, and the real-time detection within 90 min in an automatic format. A limit of detection of 5 × 10³ copies/reaction for each gene was determined with three samples including synthesized RNAs, inactive viruses, and RNAs extracted from clinical samples; this compact platform could be a useful tool for COVID-19 diagnostics.

Assessment of the Risk of Severe Dengue Using Intrahost Viral Population in Dengue Virus Serotype 2 Patients via Machine Learning

Dengue virus, a positive-sense single-stranded RNA virus, continuously threatens human health. Although several criteria for evaluation of severe dengue have been recently established, the ability to prognose the risk of severe outcomes for dengue patients remains limited. Mutant spectra of RNA viruses, including single nucleotide variants (SNVs) and defective virus genomes (DVGs), contribute to viral virulence and growth. Here, we determine the potency of intrahost viral population in dengue patients with primary infection that progresses into severe dengue. A total of 65 dengue virus serotype 2 infected patients in primary infection including 17 severe cases were enrolled. We utilized deep sequencing to directly define the frequency of SNVs and detection times of DVGs in sera of dengue patients and analyzed their associations with severe dengue. Among the detected SNVs and DVGs, the frequencies of 9 SNVs and the detection time of 1 DVG exhibited statistically significant differences between patients with dengue fever and those with severe dengue. By utilizing the detected frequencies/times of the selected SNVs/DVG as features, the machine learning model showed high average with a value of area under the receiver operating characteristic curve (AUROC, 0.966 ± 0.064). The elevation of the frequency of SNVs at E (nucleotide position 995 and 2216), NS2A (nucleotide position 4105), NS3 (nucleotide position 4536, 4606), and NS5 protein (nucleotide position 7643 and 10067) and the detection times of the selected DVG that had a deletion junction in the E protein region (nucleotide positions of the junction: between 969 and 1022) increased the possibility of dengue patients for severe dengue. In summary, we demonstrated the detected frequencies/times of SNVs/DVG in dengue patients associated with severe disease and successfully utilized them to discriminate severe patients using machine learning algorithm. The identified SNVs and DVGs that are associated with severe dengue will expand our understanding of intrahost viral population in dengue pathogenesis.

Synergistic surface-enhanced Raman scattering effect to distinguish live SARS-CoV-2 S pseudovirus

The COVID-19 pandemic negatively affected the economy and health security on a global scale, causing a drastic change on lifestyle, calling a need to mitigate further transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Surface-enhanced Raman spectroscopy (SERS) has shown great potential in the sensitive and rapid detection of various molecules including viruses, through the identification of characteristic peaks of their outer membrane proteins. Accurate detection can be developed through the synergistic integration effect among SERS-active substrate, the appropriate laser wavelength, and the target analyte. In this study, gold nanocavities (Au NC) and Au nanoparticles upon ZrO₂ nano-bowls (Au NPs/pZrO₂) were tested and used as SERS-active substrates in detecting SARS-CoV-2 pseudovirus containing S protein as a surface capsid glycoprotein (SARS-CoV-2 S pseudovirus) and vesicular stomatitis virus G (VSV-G) pseudo-type lentivirus (VSV-G pseudovirus) to demonstrate their virus detection capability. The optimized Au NCs and Au NPs/pZrO₂ substrates were then verified by examining the repetition of measurement, reproducibility, and detection limit. Due to the difference in geometry and composition of the substrates, the characteristic peak-positions of live SARS-CoV-2 S and VSV-G pseudoviruses in the obtained Raman spectra vary, which were also compared with those of inactivated ones. Based on the experimental results, SERS mechanism of each substrate to detect virus is proposed. The formation of hot spots brought by the synergistic integration effect among substrate, analyte, and laser induction may result differences in the obtained SERS spectra.

Morphologic Spectrum of Lymphadenopathy in Drug Reaction With Eosinophilia and Systemic Symptoms Syndrome

CONTEXT.—

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DRESS) is a drug-induced, adverse T-cell-mediated hypersensitivity reaction that most often involves skin. The pathologic findings of DRESS-related lymphadenopathy have been described infrequently in the literature.

OBJECTIVE.—

To present a case series of DRESS-related lymphadenopathy with an emphasis on the morphologic spectrum.

DESIGN.—

We describe detailed clinical and pathologic findings along with the literature review. We focus on the differential diagnosis between DRESS lymphadenopathy and angioimmunoblastic T-cell lymphoma (AITL).

RESULTS.—

There were 4 men and 1 woman with a mean age of 41 years (range, 23-59 years). One patient (20%) died. Three lymph node biopsy specimens showed a pattern reminiscent of AITL (AITL-like pattern) and 2 cases showed necrotizing lymphadenitis (Kikuchi-like pattern), associated with vasculitis in 1 case. The AITL-like morphology of DRESS-related lymphadenopathy may be difficult to distinguish from genuine AITL. The clinical information is important for differential diagnosis, including history of drug exposure, age, and the rarity or absence of AITL-associated manifestations such as hemolytic anemia and hypergammaglobulinemia. Molecular analysis of the T-cell receptor genes is helpful, typically revealing a polyclonal pattern in DRESS-related lymphadenopathy.

CONCLUSIONS.—

In the literature, 4 histologic patterns of DRESS lymphadenopathy have been described: reactive lymphoid hyperplasia, necrotizing lymphadenitis, Hodgkin lymphoma-like, and AITL-like. These patterns, particularly those that resemble lymphoma, highlight the importance of correct diagnosis to avoid unnecessary therapies.

Clinical and Immune Responses of Peripheral Chemical Sympathectomy in Enterovirus 71 Infection

The activation of the sympathetic nervous system, release of norepinephrine (NE), and adrenergic receptor signaling participate in and regulate the complicated enterovirus 71 (EV71) brainstem encephalitis (BE). The neurotoxin 6-hydroxydopamine (6-OHDA) selectively ablates sympathetic nerves and markedly depletes NE in innervated organs. Changes in the plasma levels of NE, severity score, cytokine profiles, and percentages of immunophenotype expression in 7-day-old Bltw : CD1 (ICR) mice infected with EV71, with or without 6-OHDA treatment, were compared. The survival rate (76.9%) of EV71-infected and 6-OHDA (30 μg/g)-treated mice was increased significantly. The clinical scores were decreased markedly on days 8-12 in MP4-infected and 6-OHDA-treated mice compared to those without treatment. The results showed that the plasma levels of NE, epinephrine, and dopamine were decreased on days 4–8 after 6-OHDA treatment and at most on day 8. The plasma levels of interleukin (IL)-12p70, tumor necrosis factor, IL-6, and IL-10 did not change significantly after 6-OHDA treatment. Interferon-γ levels decreased evidently on days 4, 6, and 8 after 6-OHDA treatment. The absolute events of CD3⁺CD4⁺, CD3⁺CD8⁺, and CD3⁺NK1.1⁺ cells of peripheral blood mononuclear cells were increased significantly in MP4-infected and 6-OHDA-treated mice compared to those without treatment. In splenocytes, the absolute cells of CD3⁻NK1.1⁺, CD3⁺NK1.1⁺ and CD11b⁺Gr-1⁺ cells of EV71-infected mice were increased significantly after 6-OHDA treatment. These findings suggested that 6-OHDA may be used a probe to explore clinical improvements and immune responses in the complicated EV71 infection. Taken together, peripheral chemical sympathectomy contribute to further understand the immunopathogenesis of EV71 BE with autonomic nervous system dysregulation.

Challenges of SERS technology as a non-nucleic acid or -antigen detection method for SARS-CoV-2 virus and its variants

The COVID-19 pandemic has caused a significant burden since December 2019 that has negatively impacted the global economy owing to the fact that the SARS-CoV-2 virus is fast-transmitting and highly contagious. Efforts have been taken to minimize the impact through strict screening measures in country borders in order to isolate potential virus carriers. Effective fast-screening methods are thus needed to identify infected individuals. The standard diagnostic methods for screening SARS-CoV-2 virus have always been to perform nucleic acid-based and serological tests. However, with each having drawbacks on producing false results at very early or later stage after symptoms onset, supplementary techniques are needed to back up these tests. Surface-enhanced Raman spectroscopy (SERS) as a detection technique has continuously advanced throughout the years in terms of sensitivity and capability to detect ultralow concentration of analytes ranging from single molecule to pathogens, to present as a highly potential alternative to known sensing methods. SERS technology as a candidate for an alternative and supplementary diagnostic method for the viral envelope of SARS-CoV-2 virus is presented, comparing its pros and cons to the standard methods and what other aspects it could offer that the other methods are not capable of. Factors that contribute to the detection effectivity of SERS is also discussed to show the advantages and limitations of this technique. Despite its promising capabilities, challenges like sources of SARS-CoV-2 virus and its variations, reliable SERS spectra, mass production of SERS-active substrates, and compliance to regulations for wide-scale testing scenario are highlighted.

Invasive pulmonary aspergillosis is associated with cytomegalovirus viremia in critically ill patients - A retrospective cohort study

BACKGROUND/PURPOSE

Cytomegalovirus (CMV) viremia is associated with a higher mortality rate and prolonged intensive care unit (ICU) stay for critically ill patients. CMV infection causes transient but substantial immunosuppression for transplant recipients, increasing risk of fungal infection. The association between CMV viremia and invasive pulmonary aspergillosis (IPA) for critically ill patients is still unknown.

METHODS

We retrospectively analyzed patients received bronchoalveolar lavage (BAL), galactomannan test, influenza survey and blood CMV viral load test in ICUs of a university hospital between April 2017 and May 2020. Independent risks for IPA were analyzed by multivariable logistic regression.

RESULTS

A total of 136 patients were included. Twenty-one patients had IPA, 48 patients had CMV viremia and 22 patients had influenza. In a multivariable logistic regression model, patients with CMV viremia or influenza had higher IPA risk (adjusted odds ratio, 3.98 and 8.72; 95% CI, 1.26-12.60 and 2.64-28.82; p value = 0.019 and <0.001, respectively.). Patients with detectable CMV in BAL fluid did not have higher IPA risk (crude odds ratio, 0.95; 95% CI, 0.33-2.79; p value = 0.933). After stratifying patients by CMV viral load, the IPA risk is higher for patients with higher viral loads. There is an additive synergistic effect on IPA risk between CMV viremia and influenza infection.

CONCLUSION

For critically ill patients, CMV viremia is an independent risk factor of IPA. Patients with higher blood CMV viral loads have a higher risk of IPA. CMV viremia and influenza have an additive synergistic effect for IPA risk in critically ill patients.

Challenges of SERS technology as a non-nucleic acid or -antigen detection method for SARS-CoV-2 virus and its variants

The COVID-19 pandemic has caused a significant burden since December 2019 that has negatively impacted the global economy owing to the fact that the SARS-CoV-2 virus is fast-transmitting and highly contagious. Efforts have been taken to minimize the impact through strict screening measures in country borders in order to isolate potential virus carriers. Effective fast-screening methods are thus needed to identify infected individuals. The standard diagnostic methods for screening SARS-CoV-2 virus have always been to perform nucleic acid-based and serological tests. However, with each having drawbacks on producing false results at very early or later stage after symptoms onset, supplementary techniques are needed to back up these tests. Surface-enhanced Raman spectroscopy (SERS) as a detection technique has continuously advanced throughout the years in terms of sensitivity and capability to detect ultralow concentration of analytes ranging from single molecule to pathogens, to present as a highly potential alternative to known sensing methods. SERS technology as a candidate for an alternative and supplementary diagnostic method for the viral envelope of SARS-CoV-2 virus is presented, comparing its pros and cons to the standard methods and what other aspects it could offer that the other methods are not capable of. Factors that contribute to the detection effectivity of SERS is also discussed to show the advantages and limitations of this technique. Despite its promising capabilities, challenges like sources of SARS-CoV-2 virus and its variations, reliable SERS spectra, mass production of SERS-active substrates, and compliance to regulations for wide-scale testing scenario are highlighted.

Application of an Artificial Intelligence Trilogy to Accelerate Processing of Suspected Patients With SARS-CoV-2 at a Smart Quarantine Station: Observational Study

Background

As the COVID-19 epidemic increases in severity, the burden of quarantine stations outside emergency departments (EDs) at hospitals is increasing daily. To address the high screening workload at quarantine stations, all staff members with medical licenses are required to work shifts in these stations. Therefore, it is necessary to simplify the workflow and decision-making process for physicians and surgeons from all subspecialties.

Objective

The aim of this paper is to demonstrate how the National Cheng Kung University Hospital artificial intelligence (AI) trilogy of diversion to a smart quarantine station, AI-assisted image interpretation, and a built-in clinical decision-making algorithm improves medical care and reduces quarantine processing times.

Methods

This observational study on the emerging COVID-19 pandemic included 643 patients. An “AI trilogy” of diversion to a smart quarantine station, AI-assisted image interpretation, and a built-in clinical decision-making algorithm on a tablet computer was applied to shorten the quarantine survey process and reduce processing time during the COVID-19 pandemic.

Results

The use of the AI trilogy facilitated the processing of suspected cases of COVID-19 with or without symptoms; also, travel, occupation, contact, and clustering histories were obtained with the tablet computer device. A separate AI-mode function that could quickly recognize pulmonary infiltrates on chest x-rays was merged into the smart clinical assisting system (SCAS), and this model was subsequently trained with COVID-19 pneumonia cases from the GitHub open source data set. The detection rates for posteroanterior and anteroposterior chest x-rays were 55/59 (93%) and 5/11 (45%), respectively. The SCAS algorithm was continuously adjusted based on updates to the Taiwan Centers for Disease Control public safety guidelines for faster clinical decision making. Our ex vivo study demonstrated the efficiency of disinfecting the tablet computer surface by wiping it twice with 75% alcohol sanitizer. To further analyze the impact of the AI application in the quarantine station, we subdivided the station group into groups with or without AI. Compared with the conventional ED (n=281), the survey time at the quarantine station (n=1520) was significantly shortened; the median survey time at the ED was 153 minutes (95% CI 108.5-205.0), vs 35 minutes at the quarantine station (95% CI 24-56; P<.001). Furthermore, the use of the AI application in the quarantine station reduced the survey time in the quarantine station; the median survey time without AI was 101 minutes (95% CI 40-153), vs 34 minutes (95% CI 24-53) with AI in the quarantine station (P<.001).

Conclusions

The AI trilogy improved our medical care workflow by shortening the quarantine survey process and reducing the processing time, which is especially important during an emerging infectious disease epidemic.

The cellular immunophenotype expression of influenza A virus and influenza B virus infection in children

BACKGROUND

The innate immune response is the primary defense against influenza virus infection.

METHODS

This is a prospective study carried out in children <18 years of age who were diagnosed with influenza A or influenza B infection. Demographic and clinical data, laboratory findings and cell immunophenotypes on first presentation were compared.

RESULTS

With respect to immunophenotype, influenza A infection resulted in a higher fraction of CD14⁺ and CD4⁺IL-17A⁺cells compared to children infected with influenza B. By contrast, influenza B infection resulted in a comparatively higher percentage of double-negative CD4^-CD8^- lymphocyte subsets. Influenza A infection was associated with comparatively higher percentages of CD4⁺CD25^highFoxp3⁺ and CD4⁺CD25^lowFoxp3⁺ cells. By contrast, the percentage of CD8⁺CD25^high and CD8⁺CD25^low cells was similar among patients with influenza A infection and influenza B infection.

CONCLUSIONS

An improved understanding of the fraction of regulatory T cells with influenza virus infections may provide further understandings on immune responses.

Increasing Cytomegalovirus Detection Rate from Respiratory Tract Specimens by a New Laboratory-Developed Automated Molecular Diagnostic Test

Lots of automated molecular methods for detecting cytomegalovirus (CMV) DNA in the blood are available, but seldom for various clinical specimens. This study was designed to establish a highly sensitive automated assay to detect CMV DNA in non-blood specimens. We designed a new QMT assay using QIAGEN artus CMV RG polymerase chain reaction (Q-CMV PCR) kit applied on the BD MAX system and compared with the other assays, including an RGQ assay (LabTurbo auto-extraction combined Q-CMV PCR kit on Rotor-Gene-Q instrument), and in-house PCR assay. A total of 1067 various clinical samples, including 426 plasma, 293 respiratory tract specimens (RTS), 127 stool, 101 cerebral spinal fluid, 90 vitreous humours were analysed. Examining CMV DNA in simultaneous specimens of the same immunocompromised patient with respiratory symptoms, the detection rate of RTS (93.6%, 88/94) was significant higher than plasma (65.9%, 62/94). The positive rates for plasma samples with a low CMV viral load (<137 IU/mL) and diagnostic sensitivity of QMT, RGQ, and in-house assays were 65% and 99.1%, 45% and 100%, 5% and 65.5%, respectively. The QMT assay performs better, with shorter operational and turnaround time than the other assays, enabling the effective and early detection of CMV infection in various clinical specimens, particularly for RTS.

Genetic variations on 31 and 450 residues of influenza A nucleoprotein affect viral replication and translation

Background

Influenza A viruses cause epidemics/severe pandemics that pose a great global health threat. Among eight viral RNA segments, the multiple functions of nucleoprotein (NP) play important roles in viral replication and transcription.

Methods

To understand how NP contributes to the virus evolution, we analyzed the NP gene of H3N2 viruses in Taiwan and 14,220 NP sequences collected from Influenza Research Database. The identified genetic variations were further analyzed by mini-genome assay, virus growth assay, viral RNA and protein expression as well as ferret model to analyze their impacts on viral replication properties.

Results

The NP genetic analysis by Taiwan and global sequences showed similar evolution pattern that the NP backbones changed through time accompanied with specific residue substitutions from 1999 to 2018. Other than the conserved residues, fifteen sporadic substitutions were observed in which the 31R, 377G and 450S showed higher frequency. We found 31R and 450S decreased polymerase activity while the dominant residues (31 K and 450G) had higher activity. The 31 K and 450G showed better viral translation and replication in vitro and in vivo.

Conclusions

These findings indicated variations identified in evolution have roles in modulating viral replication in vitro and in vivo. This study demonstrates that the interaction between variations of NP during virus evolution deserves future attention.

Hepatitis B virus surface gene pre-S2 mutant as a high-risk serum marker for hepatoma recurrence after curative hepatic resection

Chronic hepatitis B virus (HBV) infection is the major cause of hepatocellular carcinoma (HCC). The pre-S₂ mutant large HBV surface antigen (LHBS) is highly associated with HCC. This study analyzed the expression of the large form of surface protein in tumors and evaluated the LHBS with mutations within the pre-S₂ region as a high-risk recurrence marker in HCC patients after curative hepatic resection. By analyses using immunohistochemical staining (n = 12) and western blotting (n = 22), the HBV surface protein, which is mainly comprised of the major form of HBV surface antigen, was greatly diminished in the tumors. However, LHBS was not significantly decreased in tumorous regions, suggesting that LHBS maintains its expression in cancer development. A cohort of 175 patients with HBV-related HCC who underwent curative hepatic resection was analyzed for pre-S gene mutations using Pre-S Gene Chip. Results of the multivariate regression analysis showed that the serum pre-S₂ mutant level and the American Joint Committee on Cancer stage were the two main independent high-risk factors for recurrence. A Cox proportional hazards analysis also revealed a prediction model, which indicated the recurrence-free survival rate along with the time after surgery; this was developed and further validated in an independent HCC cohort. Receiver operating characteristic curve analysis revealed that the model showed close sensitivities in the main and validation cohorts (area under the curve values, 0.741 and 0.704, respectively). Conclusion: Unlike the major HBV surface antigen, LHBS is mostly expressed in the tumorous regions of HBV-induced HCC, indicating that it plays a unique role in tumor progression; the relative level of pre-S₂ mutant in serum is, independently of tumor stage, an important high-risk marker for HCC recurrence after primary hepatic resection. (Hepatology 2018).

Glycan-binding preferences and genetic evolution of human seasonal influenza A(H3N2) viruses during 1999-2007 in Taiwan

It is generally agreed that human influenza virus preferentially binds to α-2,6-linked sialic acid-containing receptors, and mutations that change the binding preference may alter virus infectivity and host tropism. Limited information is available on the glycan-binding specificity of epidemic influenza viruses. In this study, we systemically investigated the glycan-binding preferences of human influenza A(H3N2) viruses isolated from 1999 to 2007 in Taiwan using a high-throughput carbohydrate array. The binding patterns of 37 H3N2 viruses were classified into three groups with significant binding-pattern variations. The results showed that the carbohydrate-binding patterns of H3N2 varied over time. A phylogenetic analysis of the hemagglutinin gene also revealed progressive drift year to year. Of note, the viruses that caused large outbreaks in 1999 and 2003 showed glycan-binding preferences to both α-2,3 and α-2,6 sialylated glycans. Twenty amino acid substitutions were identified primarily at antigenic sites that might contribute to H3N2 virus evolution and the change in the glycan-binding patterns. This study provides not only a systematic analysis of the receptor-binding specificity of influenza clinical isolates but also information that could help to monitor the outbreak potential and virus evolution of influenza viruses.

Macrophage migration inhibitory factor is critical for dengue NS1-induced endothelial glycocalyx degradation and hyperpermeability

Vascular leakage is one of the salient characteristics of severe dengue. Nonstructural protein 1 (NS1) of dengue virus (DENV) can stimulate endothelial cells to secrete endothelial hyperpermeability factor, macrophage migration inhibitory factor (MIF), and the glycocalyx degradation factor heparanase 1 (HPA-1). However, it is unclear whether MIF is directly involved in NS1-induced glycocalyx degradation. In this study, we observed that among NS1, MIF and glycocalyx degradation-related molecules, the HPA-1, metalloproteinase 9 (MMP-9) and syndecan 1 (CD138) serum levels were all increased in dengue patients, and only NS1 and MIF showed a positive correlation with the CD138 level in severe patients. To further characterize and clarify the relationship between MIF and CD138, we used recombinant NS1 to stimulate human cells in vitro and challenge mice in vivo. Our tabulated results suggested that NS1 stimulation could induce human endothelial cells to secrete HPA-1 and immune cells to secrete MMP-9, resulting in endothelial glycocalyx degradation and hyperpermeability. Moreover, HPA-1, MMP-9, and CD138 secretion after NS1 stimulation was blocked by MIF inhibitors or antibodies both in vitro and in mice. Taken together, these results suggest that MIF directly engages in dengue NS1-induced glycocalyx degradation and that targeting MIF may represent a possible therapeutic approach for preventing dengue-induced vascular leakage.

Validation and Application of a Commercial Quantitative Real-Time Reverse Transcriptase-PCR Assay in Investigation of a Large Dengue Virus Outbreak in Southern Taiwan

Background

Accurate, rapid, and early diagnosis of dengue virus (DENV) infections is essential for optimal clinical care. Here, we evaluated the efficacy of the quantitative real-time PCR (qRT-PCR)-LightMix dengue virus EC kit for DENV detection using samples from a dengue outbreak in Taiwan in 2015.

Methods

Sera from patients with suspected DENV infection were analyzed and compared using the LightMix kit, a Dengue NS1 Ag + Ab Combo kit for detection of NS1 antigen and DENV-specific IgM and IgG antibodies, and an “in-house” qualitative DENV-specific RT-PCR assay.

Results

A total of 8,989, 8,954, and 1581 samples were subjected to NS1 antigen detection, IgM and IgG detection, and LightMix assays, respectively. The LightMix assay yielded a linear curve for viral loads (VL) between 10² and 10⁶ copies/reaction, and the minimum detection limits for DENV serotype 1 (DENV1) and DENV2, DENV3, and DENV4 were 1, 10, and 100 focus forming units (FFU)/mL, respectively. There was 88.9% concordance between the results obtained using the NS1 antigen combo kit and by LightMix analysis, and the diagnostic sensitivity and specificity of the two methods were 89.4 and 100%, and 84.7 and 100%, respectively. Notably, fatal cases were attributed to DENV2 infection, and 79.5% (27/34) of these cases occurred in patients ≥ 71 years of age. Among these older patients, 82.3% (14/17) were NS1/IgM/IgG (+/-/-), exhibiting VLs between 10⁶–10⁹ copies/mL, which was markedly higher than the rate observed in the other age groups.

Conclusions

The LightMix assay was effective for early diagnosis of DENV infection. Our data indicate that high VLs during primary infection in elderly patients may be a positive predictor for severe illness, and may contribute to high mortality rates.

The LightMix dengue virus EC qRT-PCR assay is effective for early diagnosis of DENV infection. High viral loads during primary infection in elderly patients may comprise a positive predictor for severe illness, and may contribute to high mortality rates.

Molecular Epidemiology and Clinical Manifestations of Adenovirus Respiratory Infections in Taiwanese Children

Human adenoviruses (HAdVs) are important causes of respiratory infections in children. They usually cause mild upper respiratory symptoms, but they can also produce severe pneumonia and other complications. The aims of this retrospective study were to better define the molecular epidemiology of respiratory adenoviruses circulating in Taiwanese children during 2002 and 2013, detect reinfections and co-infections, and characterize the clinical features and laboratory findings according to the causative genotypes.We collected a representative sample of 182 isolates of adenoviruses from 175 children during the 12-year study period. The most prevalent species was HAdV-B genotype 3 (HAdV-3) (92/182, 50.5%) followed by HAdV-C (HAdV-2) (38/182, 20.9%). A single outbreak of HAdV-E (6/182, 3.3%) was noted in 2007. The mean age of children with adenovirus infections was 3.7 ± 2.0 years, with a slight predominance of males (53.1%). Children with HAdV-B tended to be older, had more lower respiratory tract infections, gastrointestinal symptoms, and a higher rate of hospitalization than those with HAdV-C (P < 0.05). Adenovirus co-infections were noted in 25/175 (14.3%) of the children. The most frequent co-infections were with species B (HAdV-3) and C (HAdV-2) (14/25, 56.0%). Additional infections were noted in 23/175 (13.1%) of the children. Of these repeated infections, the initial isolates were always genotypes of HAdV-C. The second isolates were genotypes of HAdV-B or HAdV-E. The clinical features of the first HAdV-B infection and the reinfection of HAdV-B followed the HAdV-C were similar.In conclusion, HAdV-B, C, and E were the only adenovirus species that were isolated from children who were sufficiently ill with respiratory infections to require a visit to the hospital. Human adenovirus B (HAdV-3) accounted for half of these species. HAdV-B was more likely than other species to produce severe disease. The high incidence of adenovirus co-infection and reinfections with different HAdV species supports the need for continued surveillance and has major implications for development of vaccines.

Mutations in the non-structural protein region contribute to intra-genotypic evolution of enterovirus 71

Background

Clinical manifestations of enterovirus 71 (EV71) range from herpangina, hand-foot-and-mouth disease (HFMD), to severe neurological complications. Unlike the situation of switching genotypes seen in EV71 outbreaks during 1998–2008 in Taiwan, genotype B5 was responsible for two large outbreaks in 2008 and 2012, respectively. In China, by contrast, EV71 often persists as a single genotype in the population and causes frequent outbreaks. To investigate genetic changes in viral evolution, complete EV71 genome sequences were used to analyze the intra-genotypic evolution pattern in Taiwan, China, and the Netherlands.

Results

Genotype B5 was predominant in Taiwan’s 2008 outbreak and was re-emergent in 2012. EV71 strains from both outbreaks were phylogenetically segregated into two lineages containing fourteen non-synonymous substitutions predominantly in the non-structural protein coding region. In China, genotype C4 was first seen in 1998 and caused the latest large outbreak in 2008. Unlike shifting genotypes in Taiwan, genotype C4 persisted with progressive drift through time. A majority of non-synonymous mutations occurred in residues located in the non-structural coding region, showing annual increases. Interestingly, genotype B1/B2 in the Netherlands showed another stepwise evolution with dramatic EV71 activity increase in 1986. Phylogeny of the VP1 coding region in 1971–1986 exhibited similar lineage turnover with genotype C4 in China; however, phylogeny of the 3D-encoding region indicated separate lineage appearing after 1983, suggesting that the 3D-encoding region of genotype B2 was derived from an unidentified ancestor that contributed to intra-genotypic evolution in the Netherlands.

Conclusions

Unlike VP1 coding sequences long used for phylogenetic study of enteroviruses due to expected host immune escape, our study emphasizes a dominant role of non-synonymous mutations in non-structural protein regions that contribute to (re-)emergent genotypes in continuous stepwise evolution. Dozens of amino acid substitutions, especially in non-structural proteins, were identified via genetic changes driven through intra-genotypic evolution worldwide. These identified substitutions appeared to increase viral fitness in the population, affording valuable insights not only for viral evolution but also for prevention, control, and vaccine against EV71 infection.

High-incidence of human adenoviral co-infections in taiwan

Background

Respiratory infections caused by adenovirus (HAdV) are common year round. Recently, a significant increase of adenoviral infections was observed in Taiwan.

Objective

To understand the prevalence and molecular epidemiology of respiratory adenovirus circulating in Taiwan for the past decade.

Study Design

One hundred and twenty-six human adenoviruses, isolated between 2002 to 2011, were characterized via DNA sequencing of the hexon and fiber genes. The nucleotide sequences were then compared by phylogenetic analysis.

Results

HAdV-B3 accounted for 64.3% (81/126) and peaked almost every year, whereas the sequences of hexon and fiber genes of HAdV-B3 were highly conserved in different years. A high incidence of co-infection of adenoviruses was observed (19.0%, 24/126); HAdV-B3 co-infected with HAdV-C2 was the most common combination (58.3%, 14/24). An additional interesting finding of repeated infection was noted in 10 children, all of whom showed first infection with adenovirus species HAdV-C, followed by species HAdV-B or HAdV-E.

Conclusions

HAdV-B3 was the predominant type of respiratory adenovirus circulating in Taiwan over the past ten years. This merits further attention for vaccine development. Furthermore, the observed high-incidence of adenoviral co-infections along with repeated infections found in our study provides important epidemiological insights into adenovirus infections.

An echovirus 18-associated outbreak of aseptic meningitis in Taiwan: epidemiology and diagnostic and genetic aspects

In 2006, an outbreak of aseptic meningitis was noted in Taiwan. From January to October 2006, a total of 3283 specimens collected from patients with viral infection, including 173 cerebrospinal fluid (CSF) samples, were examined for virus isolation and identification. Overall, 339 enterovirus (EV)-positive cases were identified by virus culture: echovirus 18 (E18) formed the majority (27.4 %, 93 cases), followed by coxsackievirus B2 (13.8 %, 47 cases) and coxsackievirus A2 (10.8 %, 37 cases). The manifestations of the 93 E18 cases were aseptic meningitis (44.1 %), viral exanthema (23.6 %), acute tonsillitis (15.1 %), acute pharyngitis (14.0 %), acute gastritis (11.8 %), herpangina (7.5 %) and bronchopneumonia (5.3 %). Of 107 E18 isolates identified, 100, 62.5 and 19 % were obtained following culture in RD, MRC-5 and A549 cells, respectively. E18 was identified most frequently from throat swabs (67.2 %) and less frequently from stool samples (15.9 %) and CSF (16.8 %). The detection rate of E18 was 78.2 % from CSF, 50 % from stool samples and 22.9 % from throat swabs. Phylogenetic relationships among the E18 strains were examined. Analysis of the partial VP1 gene showed 3.7-23.8 % variation in sequence compared with sequences from GenBank and, notably, the amino acid change V152S was detected in a protruding loop within the VP1 protein. These results indicate that a genetic variant of E18 was circulating and caused an outbreak of aseptic meningitis in Taiwan in 2006.

Large B cell lymphoma presenting initially in bone marrow, liver and spleen: an aggressive entity associated frequently with haemophagocytic syndrome

AIMS

To describe diffuse large B cell lymphoma (DLBCL) presenting initially in bone marrow, liver and spleen (BLS-type) without lymphadenopathy.

METHODS AND RESULTS

The clinicopathological and cytogenetic features of 11 such cases (eight men, three women; mean age: 62.7 years are described). Usually presenting with fever and haemophagocytic syndrome suggesting infection and complicating timely diagnosis, bone marrow examination showed patchy and interstitial infiltration of large tumour cells without sinusoidal involvement. All cases had a high Ki-67 index (≥90%), commonly a non-germinal centre/activated B cell immunophenotype and were negative for Epstein-Barr virus and human herpesvirus 6 and 8. The more frequent cytogenetic changes involved chromosomal loci 14q32 and 9p24, as well as del(3)(q21), add(7)(p22), t(3;6), del(8)(p22), +18 and add(19)(p13). Clinical behaviour was very aggressive, with a 2-year survival rate of 18% (45% of patients died within 3 weeks). High-dose chemotherapy with haematopoietic stem cell transplantation prolonged survival in one patient.

CONCLUSIONS

Although it shares with intravascular LBCL a subtle presentation and an aggressive clinical course, this primary BLS large cell lymphoma variant is distinguished by lacking an intravascular component and having different cytogenetic findings.

Co-circulating genetically divergent A2 human metapneumovirus strains among children in southern Taiwan

An outbreak of human metapneumovirus (hMPV) among children in southern Taiwan in 2004 prompted the investigation of the molecular epidemiology of hMPV from September 2003 to August 2005. Respiratory specimens that were culture negative for a panel of respiratory viruses were examined for the presence of hMPV by RT-PCR. The results indicated that 59 out of 546 (10.8%) children were hMPV-positive. The majority of these hMPV-positive children were less than 2 years old (59.4%), females (61%), and inpatients (67.8%). Infections occurred throughout the year, but peaked during the spring and/or summer months. Sequence analysis of the fusion gene from the isolates revealed two phylogenetic groups with five possible lineages (A1, A2a/A2b, B1, and B2). Among these co-circulating strains, A2 strains were most frequently observed and demonstrated the greatest divergence. Deduced amino acid sequence analysis identified several variant amino acids specific to the A2 lineage. Lineage-specific amino acid substitutions were noted at aa233, aa286, aa312, aa348, and aa296. This study indicated that genetically divergent strains of hMPV which caused respiratory disease and hospitalization were circulating among children in Taiwan.

Multidetector computed tomography assessment on tumor size and nodal status in patients with locally advanced breast cancer before and after neoadjuvant chemotherapy

AIMS

To evaluate the utility of multidetector computed tomography (MCT) in assessing tumor size and nodal status in patients with advanced breast cancers before and after the neoadjuvant chemotherapy.

METHODS

Twenty-eight proven locally advanced breast cancer patients with 30 tumors were enrolled in this study. MCT was used to assess tumor size and axillary lymph nodes before and after the neoadjuvant chemotherapy. The correlation between tumor size on MCT and gross tumor size was tested.

RESULTS

The MCT measurements documented complete response in 3, partial response in 18, non-response in 8 and progressed in 1. The mean tumor diameters on pathology and post-chemotherapy MCT were 3.6cm (S.D.=+/-2.9cm) and 3.1cm (S.D.=+/-2.6cm), respectively. The Pearson correlation coefficient was 0.76 (p<0.001). The sensitivity, specificity, positive predictive valve, negative predictive valve and accuracy of MCT in diagnosing the axillary lymph node metastases after pre-operative neoadjuvant chemotherapy were counted, respectively, to 72%, 40%, 85.7%, 22.2% and 66.7%. All the 5 downstaged axillary nodal statuses from node-positive to node-negative on MCT had micrometastases.

CONCLUSION

MCT can be used to evaluate tumor size and nodal status in patients with advanced breast cancer. As there is a baseline MCT before chemotherapy for comparison, we are potentially aware of the possibility of false negative nodal micrometastases on the post-chemotherapy MCT.

Increasing appearance of reassortant influenza B virus in Taiwan from 2002 to 2005

Genetic and antigenic analyses of influenza B virus field strains isolated in Taiwan from 1998 to 2005 were performed. To investigate the molecular evolution of influenza B viruses, sequence analysis of the hemagglutinin (HA1 subunit) and neuraminidase genes was performed. All influenza B viruses isolated between 1998 and 2000 belonged to the B/Yamagata/16/88 lineage. The B/Victoria/2/87 lineage, which was cocirculating with the Yamagata lineage, was identified in Taiwan in March 2001. Concurrently, there was an increasing prevalence of this lineage in many parts of the world, including North America and Europe, during the 2001-2002 season. Since 2002, genetic reassortants of influenza B virus with the Victoria lineage of hemagglutinin and the Yamagata lineage of neuraminidase have been found at a rate of 46%. Therefore, in 2002, at least three sublineages of influenza B virus strains, the B/Shanghai/361/2002-like strain (Yamagata lineage), the B/Hong Kong/330/01-like strain (Victoria lineage), and the B/Hong Kong/1351/02-like strain (B reassortant lineage), were identified in Taiwan. The results showed that genetically distinct lineages can cocirculate in the population and that the reassortment among these strains plays a role in generating the genetic diversity of influenza B viruses. Interestingly, from January to April 2005, B reassortant viruses became dominant (73%) in Taiwan, which indicated that a mismatch had occurred between the influenza B vaccine strain recommended for the 2004-2005 season in the Northern hemisphere by the World Health Organization and the epidemic strain.

Cytogenetic anomalies in hyaline vascular Castleman disease: report of two cases with reappraisal of histogenesis

The pathogenesis of hyaline vascular Castleman disease (HVCD) is poorly understood. Although generally considered reactive in nature, a subset of cases has been shown to harbor focal proliferations of stromal cells, such as follicular dendritic cell (FDC) and angiomyoid proliferations. We report two typical cases of HVCD with cytogenetic anomalies: one was t(1;22)(qter;q13) and the other was t(7;8)(q37.3;q12) in cultured stromal cells, as demonstrated by conventional cytogenetic analysis. The cultured cells were immunoreactive for smooth muscle actin but negative for CD21, CD31, and CD34, and ultrastructurally possessed thin filaments (5-7.5 nm) with dense bodies, and pinocytotic vesicles, characteristic of smooth muscle cells. The lack of monoclonality of lymphoid cells in lesional tissues by immunohistochemical and molecular analyses also supports the origin of these anomalies from the stromal cells, most likely myoid cells. Moreover, the absence of overt stromal proliferations suggests that cytogenetic changes in stromal cells of HVCD precede histologic evidence of stromal overgrowth, which may account for the occurrence of angiomyoid proliferations arising in some cases of HVCD. Further studies with more cases are needed to decipher whether part or even most of HVCD cases bear genetic changes in the beginning of the disease without morphologically stromal overgrowth.

Laboratory diagnosis and genetic analysis of an echovirus 30-associated outbreak of aseptic meningitis in Taiwan in 2001

A large outbreak of aseptic meningitis occurred from April to November 2001 in Taiwan. Of the 1,130 enterovirus-infected patients, echovirus 30 (E30) infection was diagnosed in 188 (16.6%), with the patients having various clinical manifestations including aseptic meningitis (73.9%), young infant fever (6.9%), respiratory symptoms or herpangina (13.3%), or others (5.9%). The majority of the E30-infected patients were between 3 and 10 years old. Of the 264 E30 strains identified, 94.3, 71, and 67.4% were isolated from RD, MRC-5, and A549 cells, respectively. Primary isolation of E30 required mean times of 3.7 days for RD cells and 4.1 days for MRC-5 and A549 cells. Among all E30-positive patients, virus was most frequently isolated from throat swab specimens (85.2%) and, to a lesser extent, stool (76.4%) or cerebrospinal fluid (70.1%) specimens. The virus isolates were initially identified as echovirus 4 (E4) on the basis of immunofluorescence staining with anti-E4 and anti-E30 (Bastianni prototype) monoclonal antibodies. However, upon performance of the neutralization test, E30-specific reverse transcription-PCR, and sequencing of the VP1 gene, the results identified these isolates as E30, not E4, indicating that the reagent used to type E30, which is produced with the Bastianni strain as the immunogen, is inadequate for the identification of recent E30 isolates in Taiwan. Phylogenetic analyses of the VP1 genes of these isolates showed that their sequences differed from those of E30 isolates from the GenBank database by 9.1 to 25.2%, suggesting that this outbreak was caused by a new variant strain of E30 introduced into Taiwan in 2000 that resulted in the widespread aseptic meningitis epidemic in 2001.

Change of major genotype of enterovirus 71 in outbreaks of hand-foot-and-mouth disease in Taiwan between 1998 and 2000

Two outbreaks of hand-foot-and-mouth disease (HFMD) occurred in Taiwan between 1998 and 2000. Enteroviruses were isolated from a total of 1,892 patients in this laboratory during this period. Of the virus isolates, enterovirus 71 (EV71) was diagnosed in 44.4% of the patients (132 of 297) in 1998, 2% (13 of 646) in 1999, and 20.5% (195 of 949) in 2000. Genetic analyses of the 5'-untranslated and VP1 regions of EV71 isolates by reverse transcription-PCR and sequencing were performed to understand the diversity of EV71 in these outbreaks of HFMD. Most EV71 isolates from the 1998 epidemic belonged to genotype C, while only one-tenth of the isolates were genotype B. Interestingly, all EV71 isolates tested from 1999 to 2000 belonged to genotype B. This study indicated that two genogroups of EV71 capable of inducing severe clinical illness have been circulating in Taiwan. Furthermore, the predominant EV71 genotypes responsible for each of the two major HFMD outbreaks within the 3-year period in Taiwan were different.

Respiratory viral infections among pediatric inpatients and outpatients in Taiwan from 1997 to 1999

The present study examined the association of specific virus infections with acute respiratory tract conditions among hospitalized and outpatient children in a subtropical country. A total of 2,295 virus infections were detected in 6,986 patients between 1997 and 1999, including infections caused by respiratory syncytial virus (RSV) (1.7%), parainfluenza virus (2.0%), influenza B virus (2.6%), adenovirus (4.0%), herpes simplex virus type 1 (4. 4%), influenza A virus (5.5%), and enterovirus (12.7%). There were 61 mixed infections, and no consistent seasonal variation was found. One or more viruses were detected among 24.8% of hospitalized patients and 35.0% of outpatients. The frequencies and profiles of detection of various viruses among in- and outpatients were different. The occurrence of enterovirus infections exceeded that of other viral infections detected in 1998 and 1999 due to outbreaks of enterovirus 71 and coxsackievirus A10. RSV was the most prevalent virus detected among hospitalized children, whereas influenza virus was the most frequently isolated virus in the outpatient group. Most respiratory viral infections (39.3%) occurred in children between 1 and 3 years old. RSV (P < 0.025) and influenza A virus (P < 0.05) infections were dominant in the male inpatient group. In addition, most pneumonia and bronchiolitis (48.4%) was caused by RSV among hospitalized children less than 6 months old. Adenovirus was the most common agent associated with pharyngitis and tonsilitis (45.5%). These data expand our understanding of the etiology of acute respiratory tract viral infections among in- and outpatients in a subtropical country and may contribute to the prevention and control of viral respiratory tract infections.

Clinicopathologic factors influencing long-term survival after resection for hepatocellular carcinoma

BACKGROUND

The purpose of this study is to investigate the clinicopathologic factors that influence a survival longer than 5 years with no recurrence in patients after resection for hepatocellular carcinoma (HCC).

METHODS

Between January 1992 and December 1994, 64 patients with complete viral markers study underwent curative hepatic resection for HCC. Four patients who died of surgical morbidity (hospital mortality, 6.3%) were excluded from this study. Among the 60 patients who survived, 10 patients (16.7%) survived over 5 years without recurrence. The clinicopathologic features and surgical procedures of the patients with long-term survival (> or = 5 years) without recurrence (n = 10) were compared with those of less than 5 years survival or with tumor recurrence (n = 50). The median follow-up was 64.8 months, ranging from 61.1 to 76.7 months.

RESULTS

Six of the 10 patients were men with an age ranging from 35 to 75 years (mean, 57.6 +/- 9.7). Using univariate analysis, long-term survival without recurrence was significantly associated with a lower amount of perioperative blood transfusion (less than 7 units, p = 0.036) and an existence of tumor capsule (p = 0.031). But in multivariate analysis, only the presence of tumor capsule was statistically significant.

CONCLUSIONS

Long-term survival without recurrence was related to a lower amount of perioperative blood transfusion, and an existence of tumor capsule in univariate analysis. But in multivariate analysis, only the existence of tumor capsule plays a significant role.

Potential dengue virus-triggered apoptotic pathway in human neuroblastoma cells: arachidonic acid, superoxide anion, and NF-kappaB are sequentially involved

Direct in vivo evidence for the susceptibility of human neuronal cells to dengue virus has not been reported. In this study, we demonstrated that type 2 dengue (DEN-2) virus infection induced extensive apoptosis in the human neuroblastoma cell line SK-N-SH. Phospholipase A(2) (PLA(2)) was activated by DEN-2 infection, which led to the generation of arachidonic acid (AA). Inhibition of PLA(2) activity by the PLA(2) inhibitors, AACOCF(3) and ONO-RS-082, diminished DEN-2 virus-induced apoptosis. In contrast, the cyclooxygenase inhibitors aspirin and indomethacin, thought to increase AA accumulation by blocking AA catabolism, enhanced apoptosis. Exogenous AA induced apoptosis in a dose-dependent manner. Superoxide anion, which is thought to be generated through the AA-activated NADPH oxidase, was increased after infection. Pretreatment with superoxide dismutase (SOD) protected cells against DEN-2 virus-induced apoptosis. Furthermore, generation of superoxide anion was blocked by AACOCF(3). In addition, the transcription factors, NF-kappaB and c-Jun, were found to be activated after DEN-2 virus infection. However, pretreatment of cells with oligodeoxynucleotides containing NF-kappaB, but not c-Jun, binding sites (transcription factor decoy) strongly prevented dengue virus-induced apoptosis. The finding that AACOCF(3) and SOD significantly block activation of NF-kappaB suggests that this activation is derived from the AA-superoxide anion pathway. Our results indicate that DEN-2 virus infection of human neuroblastoma cells triggers an apoptotic pathway through PLA(2) activation to superoxide anion generation and subsequently to NF-kappaB activation. This apoptotic effect can be either directly derived from the action of AA and superoxide anion on mitochondria or indirectly derived from the products of apoptosis-related genes activated by NF-kappaB.

An outbreak of enterovirus 71 infection in Taiwan, 1998. II. Laboratory diagnosis and genetic analysis

BACKGROUND

An epidemic of enterovirus 71 (EV71) occurred in Taiwan from April to December of 1998, with two peaks, one in June and the other in October. Many enteroviruses were isolated in our laboratory from 258 cases during this outbreak. Approximately half of the enteroviruses isolated were EV71 and one fifth were coxsackievirus A16.

OBJECTIVES

To analyze laboratory findings in the EV71 epidemic of 1998 in Taiwan, various EV71 specimens in different cell lines were examined. In addition, genetic analysis of 5' non-coding region (NCR) was performed to analyze the strain variation in this outbreak.

RESULTS

The cytopathic effect induced by EV71 was observed 2-13 (mean of 4.5) days post-inoculation in Vero cells and 4-15 (mean of 6.6) days in green monkey kidney (GMK) cells inoculated with throat swabs. Of the total positive EV71 cases, virus was most frequently obtained from throat swabs (91.7%), less from stools (64.8%), and none from cerebral spinal fluid (CSF). Molecular analyses of EV71 by sequencing the 5' NCR of 34 strains obtained from different clinical categories and various geographic areas showed that their sequences differed (0-13 bp in 681 bp sequenced) by approximately 0-2%. The sequences of these isolates differed from EV71 prototype BrCr or MS strain by 17.5-19%, with the exception of two samples which exhibited nucleotide variation by only 8.9 and 8.2%, when compared to the MS strain.

CONCLUSION

EV71 was most frequently isolated from throat swab specimens in Vero cells. The molecular analyses of the 5' NCR of EV71 revealed that most isolates from this epidemic belonged to a group of closely related clones and only two were in a different group which was clustered with the EV71 MS strain.