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Mannose-binding lectin (MBL) is an important constituent of the human innate immune system, and can bind to a wide range of pathogens, including viruses such as influenza A, HIV, herpes simplex 2, and SARS-CoV. MBL deficiency results from single nucleotide polymorphisms (SNPs) in exon 1, and the promoter region of the human MBL2 gene has been found to be associated with susceptibility to a number of infections. However, studies on the interactions between MBL and CMV infection are limited. In this study, we investigated 104 children suffering from HCMV infection, in an effort to find any association between MBL and HCMV infection of children in China. We analyzed the genotypes of 104 HCMV patients and 105 healthy controls, and investigated the distributions of polymorphisms at -550(H/L), -221(Y/X), and +4(P/Q), together with their structural variants. Although there was no significant difference in the distribution of B alleles between HCMV patients and healthy controls, the frequencies of the high-MBL-level related genotype of YA type in HCMV patients were significantly lower than those seen in healthy controls, while low-level related genotypes of XB type were more common in HCMV patients. In addition, CMV-DNA quantification revealed higher viral loads of the XB type in HCMV patients. Thus we can speculate that as an acute response protein and a pattern-recognition molecule of the innate immune system, MBL may play a role in protecting against HCMV infection in children, and MBL gene mutations may be a significant risk factor for the development of infantile HCMV infection.

Wilson disease (WD) is an autosomal recessive genetic disorder associated with copper metabolism. Early diagnosis and therapy can result in good prognosis of WD. Thus, it is highly recommended to perform familial screening. In this study, we aimed to investigate the range of familial screening of children with WD and determine the appropriate screening methods. We enrolled 20 children with WD and 50 family members of each of these patients (40 parents and 10 siblings). All the subjects underwent a physical examination, Kayser–Fleischer (K-F) rings in the cornea, abdominal ultrasonography (Abdl Ur), cranial magnetic resonance imaging (MRI), serum ceruloplasmin, serum copper, 24-hour urine copper, blood alanine transaminase (ALT) and aspartate transaminase (AST), and ATP7B gene. Two new patients with presymptomatic WD (1 mother and 1 brother) in 2 families were found by screening. They had no clinical symptoms and K-F rings in corneal. Biochemical examination indicated decreased serum ceruloplasmin and serum copper in the mother and decreased serum ceruloplasmin in the brother. Gene sequencing revealed compound heterozygous mutations in them. In addition, 48 heterozygous carriers of Wilson disease (WHDzc) were found in this study. The levels of ceruloplasmin and serum copper in patients of WD were significantly less than WHDzc and 24-hour urinary copper were significantly higher than WHDzc (P = .000). The biochemical profiles of WD and WDHzc overlapped in range of 0.8 to 1.5 g/L in ceruloplasmin, above 9 μmol/L in serum copper and below 100 μg/24 h in urinary copper. Gene sequencing showed 2 pathological mutations in all patients with WD and 1 pathological mutation in all WDHzc. Not only siblings but also the previous generation of children probands with WD should be screened. Genetic testing should be conducted for the diagnosis of presymptomatic patients with WD.

To explore the effects of different acupuncture depths of Lianquan (CV 23) for dysphagia after stroke.Two hundred and fifty-one patients with dysphagia after stroke were randomly divided into a deep acupuncture group (group A, 85 cases) a shallow acupuncture group (group B, 83 cases) and a glossopharyngeum acupuncture group (group C, 83 cases). Based on the conventional treatment, the glossopharyngeum acupuncture which was pricking without needles retained at lingual surface, posterior pharyngeal wall of the affected side, Jinjin (EX-HN 12) and Yuye (EX-HN 13) was used in the three groups. After the glossopharyngeum acupuncture, Lianquan (CV 23) was acupunctured 60-70 mm in the group A and 30-40 mm in the group B. The needles were all retained for 30 min. The treatment was applied once a day for 30 days in the three groups. Water swallowing test evaluation scale was observed before and after treatment, and the efficacy was assessed in the three groups.The total effective rate was 95.3% (81/85) in the group A, which was better than 85.5% (71/83) in the group B and 83.1% (69/83) in the group C (both P0.05). The water swallowing test scores were decreased apparently in the three groups (all P0.01), and scores in the group A were the most obvious decline (P0.01). The decrease of scores in the group A was more remarkable than those in the group B and the group C after two weeks of treatment (both P0.05).Acupuncture at Lianquan (CV 23) can effectively improve the dysphagia after stroke. The acupuncture depth can affect efficacy and the effect of deep acupuncture is better.

Aim The clinical diagnosis of sepsis is difficult, particularly in neonates. It is necessary to develop a rapid and reliable method for detecting bacteria in blood and cerebrospinal fluid (CSF). Polymerase chain reaction (PCR) and reverse hybridization of the 16S rRNA gene would permit fast and sensitive determination of the presence of bacteria and differentiate gram-positive bacteria from gram-negative ones in clinical specimens. Methods We developed a pair of primers according to the gene encoding 16SrRNA found in all bacteria. DNA fragments from different bacterial species and from clinical samples were detected with PCR, and with reverse hybridization using a universal bacterial probe, a gram-positive probe and a gram-negative probe. Results A 371 bp DNA fragment was amplified from 20 different bacterial species. No signal was observed when human DNA and viruses were used as templates. The sensitivity could be improved to 10(-12) g. All 26 culture-positive clinical samples (22 blood samples and 4 CSF samples) were positive with PCR. The gram-negative and gram-positive probes hybridized to clinical samples and to known bacterial controls, as predicted by Gram's stain characteristics. Conclusions Our results suggest that the method of PCR and reverse hybridization is rapid, sensitive and specific in detecting bacterial infections. This finding may be significant in the clinical diagnosis of sepsis in neonates.

Aim: To detect and differentiate six major human herpesviruses in the cerebrospinal fluid (CSF) and blood of children by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Methods: We synthesized two pairs of primers in the well-conserved regions of the DNA polymerase gene in human herpesviruses. One pair was designed to amplify cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), and the other pair to amplify varicella-zoster virus (VZV) and human herpesvirus 6 (HHV-6) by PCR. Virus species identification was achieved by restriction enzyme digestion with BamHI and BstUI. Ninety-eight CSF and 75 blood specimens were analysed by this technique. At the same time, all blood specimens were also examined by enzyme-linked immunosorbent assay (ELISA). Results: Thirteen (13.3%) of 98 CSF specimens and 26 (34.7%) of 75 blood specimens were positive for herpesvirus DNA in this PCR assay. Only 10 (13.3%) of the blood specimens were positive in ELISA for virus-IgM antibody. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of PCR in detecting herpesvirus infections compared with ELISA were 100% (10/10), 75.4% (49/65), 38.5% (10/26) and 100% (49/49), respectively. These results indicate that the positive rate of PCR was significantly higher than that of ELISA (p

Mycoplasma pneumoniae is a particularly important pathogen that causes community acquired pneumonia in children. In this study, a rapid test was developed to diagnose M. pneumoniae by using a colloidal gold-based immuno-chromatographic assay which targets a region of the P1 gene. 302 specimens were analyzed by the colloidal gold assay in parallel with real-time PCR. Interestingly, the colloidal gold assay allowed M. pneumoniae identification, with a detection limit of 1 × 103 copies/ml. 76 samples were found to be positive in both real-time PCR and the colloidal gold assay; two specimens positive in real-time PCR were negative in the rapid colloidal gold assay. The specificity and sensitivity of the colloidal gold assay were 100% and 97.4%, respectively. These findings indicate that the newly developed immuno-chromatographic antigen assay is a rapid, sensitive and specific method for identifying M. pneumoniae, with potential clinical application in the early diagnosis of Mycoplasma pneumoniae infection.

In this study, blood culture and PCR-microarray analysis were used to examine 172 cases of suspected septicemia. Primers and oligonucleotide probes, based on the sequences of bacterial 16SrRNA gene, were arrayed by imprinting on microarray slides. Blood specimens collected from 172 cases of suspected septicemia were cultured and then tested separately by PCR for the bacterial 16S rRNA. Of the 172 clinical cases, 17 cases tested positive by PCR. The number of positives identified by PCR (9.88%) was significantly higher than the number of positives identified by the blood culture (4.65%). When blood culture was used as control, the sensitivity of PCR was 100%, the specificity was 97.85%, and the index of accurate diagnosis was 0.979. When the 17 PCR positive specimens were further analyzed by hybridization against the microarrays, five were found to be probe positive for E. coli, four were positive for S. epidermidis, four were positive for CoNS, and two were positive for Bacillus and Propionibacterium, respectively. In the eight specimens showing positive results by both PCR and blood culture, the species determined by microarray analysis corresponded with the result obtained from blood culture. Detection of the bacterial 16SrRNA genes in clinical specimens by PCR and microarray analysis can be used to accurately diagnose neonatal sepsis. This method has a higher sensitivity and specificity than blood culture and can provide a rapid way for the etiological diagnosis of neonatal septicemia.

Background There are over 100 serotypes of enterovirus species A-D, which are the common cause of various symptoms in infants, such as meningitis, encephalitis and hand foot mouth disease (HFMD). This study aims to investigate the epidemiological characteristics of enteroviruses in Hangzhou, Zhejiang province, China, and to provide relevant information to guide public health responses and interventions. Methods Systematic surveillance was conducted on enterovirus infections. Samples were collected from children admitted to the inpatient wards and outpatient departments between January 2010 and December 2012 in the Children’s Hospital, Zhejiang University School of Medicine. Enteroviruses from all specimens were detected by RT-PCR using a commercialized detection kit. Results From 13026 samples collected and examined, 2673 (21.21%) were found positive for enteroviruses. The annual enterovirus-positive rate decreased from 32.78% in 2010 to 14.23% in 2012. Positivity rate for enteroviruses was highest among children aged less than 5 years. The monthly positivity rate for enterovirus infection ranged from 2.6% to 34.83%, with a peak in June and July. Serotypes causing severe symptoms such as HFMD including EV71 and CA16 were decreasing, while the proportion of unidentified EV serotypes causing herpangina and viral encephalitis were on the rise. Conclusions EV infection is highly prevalent among young children in Hangzhou, as it is in the most other parts of the world. Further surveillance using methods that can subtype all EVs is warranted to better monitor these infections and their etiology.

Real-time polymerase chain reaction (RT-PCR) techniques have been increasingly used to detect microbial DNA in clinic for the diagnosis of bacterial infection. This study aims to developing an RT-PCR method to detect bacteria in pleural fluid (PF). We performed a method to simultaneously detect and classify the clinically relevant bacterial pathogens in hydrothorax with Gram probe RT-PCR (GRT-PCR), which targets the conserved region of the 16S rRNA gene. Our results showed this method could specifically and correctly identify 14 clinically important bacterial strains in hydrothorax including 7 gram-positive and 7 gram-negative bacteria. And the sensitivity of this GRT-PCR method in serial dilution can reach 10 CFU/mL. In clinical trial, 180 PF samples from children who were clinically suspected to suffer from bacterial pneumonia and empyema were collected. These samples were detected by GRT-PCR, standard culture, and biochemical routine analysis. The positive rate of the GRT-PCR array was 17.78% (32/180), significantly higher than that of PF culture (11.67%; 21/180; P = .003). When PF culture was used as control, the sensitivity of GRT-PCR was 95.24% (95% confidence interval = 74.13-99.75), and the specificity was 92.45% (95% confidence interval = 86.89-95.86). Our study showed that GRT-PCR is a more effective method for rapid, sensitive, and specific diagnosis of bacterial infection in hydrothorax compared with other traditional methods.

We performed a prospective observational study to evaluate the utility of measuring inflammatory cytokine levels to discriminate bacterial meningitis from similar common pediatric diseases. Inflammatory cytokine levels and other cerebrospinal fluid (CSF) physicochemical indicators were evaluated in 140 patients who were diagnosed with bacterial meningitis via microbiological culture or PCR assay. The CSF concentrations of interleukin (IL)-6 and IL-10, CSF/blood IL-6 and IL-10 ratios, CSF white blood cell count, and CSF micro total protein were significantly elevated in bacterial meningitis patients compared with healthy children or patients with viral encephalitis, epilepsy, or febrile convulsions (P

Mannose-binding lectin (MBL) has broad range of activity against viruses through the mechanisms of neutralization, opsonization, and complement activation. Prior studies have demonstrated that MBL inactivated the season's influenza virus. Due to the fact that children have no neutralizing antibody against H1N1 2009 virus, innate immunity may be crucial in the defense against influenza. Therefore, we studied whether MBL levels played a role in H1N1 2009 infection in children. In a prospective survey, we revealed that MBL levels in ICU influenza cases were significantly lower than in children with influenza from infection disease ward. MBL may be involved in innate immune responses to H1N1 2009 infection in children.

Cytomegalovirus (CMV) infection enhances expression of several cytokines, such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), granulocyte macrophage colony-stimulating factor (GM-CSF), and IL-8, to the benefit of virus replication and dissemination. However, the stimulus for certain cytokine production remains unclear. CMV encodes a series of proteins that alter and/or mimic functions of leukocyte migration, activation, and cytokine responses. Our study revealed that human CMV (HCMV)-encoded UL128 protein, which contains signal peptides and has similar amino acid sequences to the CC chemokine, recruits monocytes as human β chemokine (microphage inflammatory protein 1α). Using RNA interference technology, we constructed an HCMV (UL128⁺/UL128⁻)-infected tissue cell (MRC-5) and peripheral blood mononuclear cell (PBMC) co-culture system. We measured 6 cytokine levels (IL-2, IL-4, IL-6, IL-10, TNF-α, and interferon-γ [IFN-γ]) in the supernatant, and found significantly elevated IL-6 and elevated TNF-α levels in the HCMV UL128⁺-infected group. Conversely, we observed decreased levels in the UL128-knockout supernatant. PBMCs presented with UL128 (50 ng/mL) demonstrated better cell viability than the UL128-absent group. Finally, the MAPK/ERK pathway was found to be involved in UL128 induction of cell proliferation. Selective induction of cytokine expression indicates that HCMV-encoded UL128 is a potent inducer of several inflammatory mediators.

Objective To highlight the clinical presentations of influenza A (H1N1) infection, for early diagnosis and recognition by the pediatricians. Methods In this retrospective study, the medical records of inpatients with influenza A (H1N1) infection between November 1, 2009 and May 31, 2011were reviewed. Results Eighty pediatric in-patients with median age 41.9 mo were studied. ARDS (11/80), pneumothorax (8/80), pleural effusion (7/80) and encephalopathy (7/80) were the most frequent complications. Six of 11 ARDS patients died;all of them were under 5 y. The median days of viral shedding was 11.4 d. Slight increase of Il-6, Il-10 and TNF-γ were revealed in some cases. Conclusions During late stage of pandemic wave, the majority of patients were young children. Children with severe Influenza A (H1N1) are prone to develop complications, and die from ARDS. If influenza-like illness is accompanied by neurologic signs, influenza A (H1N1) virus infection should be considered. The viral shedding in children is longer than in adults.

A limited number of drugs have been used for treatment of human cytomegalovirus (HCMV), all sharing the similar antiviral mechanism of inhibiting virus replication. This study investigates the anti-HCMV activities of mannose-binding lectin (MBL) from blocking virus entry and inhibiting virus spread. Recombinant human MBL was produced in CHO cells and native human MBL was isolated from human serum. A HCMV neutralization test was performed by pre-treating HCMV with each diluted MBL solution. Then the treated HCMV was inoculated onto the human embryonic pulmonary fibroblasts (HELF), which was followed by HCMV-DNA detection, PP65 positivity examination and confocal imaging of the infected cells. To test the activity of MBL in inhibiting viral spreading after viral invasion, HCMV growth inhibition test was performed. The infected cells were incubated with each diluted MBL, every 24 h, the supernatant was tested for HCMV-DNA. After 72 h, cells were collected for HCMV-DNA and PP65 examination. Then the cytopathic effect was observed and cell viability was measured at the 5 days after infection. HCMV neutralization test revealed 10 μg/mL MBL significantly decreased the HCMV invasion in HELF and the anti-HCMV activity can be blocked by 20 mg/mL mannan. HCMV growth inhibition test indicated that at 48 h after HCMV invasion, the HCMV-DNA level in the culture supernatant with 10 μg/mL MBL was lower than the control. After 72 h, both the HCMV-DNA levels and PP65 positivity in cells incubated with MBL were reduced. This is the first to report on the anti-HCMV activities of MBL by in vitro studies.

This retrospective study was conducted to estimate the shedding of 2009 H1N1 virus and the risk analysis by review of medical charts, laboratory and radiological findings of all inpatients with confirmed pandemic influenza A (H1N1) at a provincial pediatric hospital. A total of 41 cases attending the inpatient department between 15 November, 2009 to 14 December, 2009 were included. Prolonged and discontinuous shedding of 2009 H1N1 virus (median, 10 days; range, 2 to 24 days) were detected by real-time RT-PCR. The interval from onset of symptom to the start of oseltamivir therapy was an independent risk factor for prolonged virus shedding.

The authors report a case of hemophagocytic lymphohistiocytosis that became apparent and was confirmed by a specific Th1/Th2 cytokine pattern at the initiation of Kawasaki disease in an 18-month-old child. His condition deteriorated fast and produced no response to intravenous immunoglobulin and dexamethasone. A standard HLH-2004 regimen was started. But he developed respiratory failure, seizure, and cardiac arrest, and died. This case is unique for developing hemophagocytic lymphohistiocytosis at the initiation of Kawasaki disease, with fatal outcome. This case may indicate a yet unknown mechanism triggers these 2 diseases; a specific Th1/Th2 cytokine pattern helps rapid differential diagnosis between these 2 diseases.

The aim of the study was to evaluate retrospectively the usefulness of polymerase chain reaction (PCR)-microarray technology, which can simultaneously detect seven human herpes viruses for rapid and accurate diagnosis of herpetic encephalitis in children. We simultaneously amplified herpes simplex virus type 1 and type 2 (HSV-1 and HSV-2); varicella-zoster virus; Epstein-Barr virus (EBV); cytomegalovirus (CMV); and human herpes virus 6 (HHV-6A and HHV-6B) by multiplex PCR, and genotyped by DNA microarray technology. The multiplex primers and oligonucleotide probes were designed and synthesized based on the highly conserved regions of the DNA polymerase gene in human herpes viruses. Two hundred ninety cerebrospinal fluid (CSF) specimens from children with clinical suspicion of viral encephalitis were screened by PCR-microarray technology. The results were compared with those of TaqMan PCR kits of common herpes virus. The PCR-microarray technology could detect as few as 10 copies of viral loads. There was no nonspecific hybridizing signal between probes and no cross-reaction to DNA extracted from the pathogens we used. Of 290 cases, 11 were tested positive by PCR-microarray technology. Among them, three were positive for HSV-1, two were positive for HSV-2, one was positive for EBV, two were positive for CMV, two were positive for HHV-6A, one was positive for HHV-6B, and one showed mixed infection of HSV-2 and CMV, and the positive rate was 3.8%. Compared with the results of TaqMan PCR, the sensitivity of PCR-microarray technology was 91.7%, the specificity was 100%, and the index of accurate diagnosis was 0.917. None of the 30 control CSF specimens was tested positive in both methods. Our study suggests that the simultaneous detection of seven human herpes viruses by PCR-microarray technology is the method of choice for rapid, accurate, and specific etiological diagnosis of herpetic encephalitis in children.

The aim of this study is to try to develop an RNA interference (RNAi) approach to human cytomegalovirus (HCMV) therapy by inhibition of viral DNA polymerase (product of the UL54 gene) expression in vitro. The fusion protein expression plasmid pEGFP-UL54 was constructed and cotransfected into AD293 cells with the lentiviral vector pGCL-GFP expressing small hairpin RNA (shRNA) especially targeting the UL54 gene. At 24, 48, and 72 h posttransfection, expression of the fusion protein was detected by fluorescence microscopy and Western blot. The level of UL54 mRNA was semiquantitated by reverse transcription polymerase chain reaction. It was found that, compared with the negative control, expression of the EGFP-UL54 fusion protein was efficiently inhibited and the mRNA level of the UL54 gene decreased significantly in cells introduced with a shRNA producing plasmid called pGCL-UL54-1479. However, the plasmid pGCL-UL54-2884 had no significant inhibitive effect on protein expression or mRNA level. It may be concluded that introduction of shRNA targeting UL54 gene of HCMV could specifically inhibit the expression of viral DNA polymerase in vitro. Nucleotides 1479-1499 of the UL54 gene seems to be an effective target site of RNAi.

To establish the specific 16S-23S rRNA gene spacer regions in different bacteria using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), DNA cloning and sequences analysis.A pair of primers were selected from highly conserved sequences adjacent to the 16S-23S rRNA spacer region. Bacterial DNA from sixty-one strains of standard bacteria and corresponding clinical isolates representative of 20 genera and 26 species was amplified by PCR, and further analyzed by RFLP, DNA cloning and sequences analysis. Furthermore, all specimens were examined by bacterial culturing and PCR-RFLP analysis. The evaluation of these assays in practical clinic practice was also discussed.Restriction enzyme analysis revealed one, two or three bands or more observed among the 26 different standard strains. The sensitivity of PCR reached 2.5 colony-forming unit (CFU), and there was no cross reaction with human genomic DNA, fungus or virus. Fourteen species could be distinguished immediately by PCR, while another 10 species were further identified by Hinf I or Alu I digestion. The only difference between K.pneumoniae and E. durans was located at the site of the 779th nucleotide according to the sequence analysis and only XmaIII digestion could distinguish one from another. Of 42 specimens from septicemic neonates, 15 were identified as positive by blood culture at a rate of 35.7%. However, 27 specimens identified as positive by PCR, with a rate of 64.2%, a method significantly more effective than blood culture (P0.01). Of 6 cerebrospinal fluid (CSF) specimens, one tested positive for S.epidermidis was also positive by PCR, two culture negative were positive by PCR and diagnosed as S.epidermidis according to the DNA pattern. One positive for C.neoformans was negative by PCR. The other two specimens were negative by both PCR and culture.The method of detecting bacterial 16S-23S rRNA spacer regions using PCR-RFLP techniques was specific, sensitive, rapid and accurate in providing a new technique for detecting pathogens in clinical bacterial infections.

SummaryBackgroundMannose-binding lectin (MBL) is a collagen-like serum protein that plays an important role in first-line host defense, especially in infants and young children. The objective of this study was to explore the genetic polymorphisms and serum protein levels of MBL in Chinese pediatric patients with common infectious diseases, including recurrent respiratory infection (RRI), acute respiratory infection (ARI), active cytomegalovirus (CMV) infection, localized abscess, and otitis media.MethodsMBL genetic polymorphisms of 151 pediatric patients with infectious diseases and 105 healthy controls were detected by PCR and sequencing. Serum MBL levels of all the patients and controls were measured using a Human MBL ELISA Kit. Differences in MBL genetic polymorphisms and serum levels between patients and controls were analyzed by statistical methods.ResultsThe frequencies of allele H/L at position −550 of the promoter and three haplotypes – HYPA, HYPB, and LYPB – were statistically different between patients and controls (p