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Chain Reaction Detection (chain + reaction_detection)
Kinds of Chain Reaction Detection Selected AbstractsSignificance of bacterial identification by molecular biology methodsENDODONTIC TOPICS, Issue 1 2004David A. Spratt Rapid advances in molecular biology over the last 20 years have provided a bewildering array of techniques aimed at helping us to tease apart all aspects of biology. The discipline of microbiology has gained greatly from these advances especially with respect to detection and identification of micro-organisms. Indeed these molecular biology techniques have changed the way we classy all life on Earth. An important part of endodontic microbiology is detection and identification of the micro-organisms associated with initiation and progression of this polymicrobial infection. A range of appropriate molecular techniques are reviewed in the present article and include aspects of comparative 16S rRNA gene sequencing, polymerase chain reaction detection, strategies for identification of unculturable bacteria, and whole community analysis. Some of these techniques are widely used in endodontic microbiology while others are used by only a few workers. The advantages and disadvantages of all the techniques are discussed and put into perspective. [source] Viral respiratory infections in hospitalized and community control children in Alaska,,JOURNAL OF MEDICAL VIROLOGY, Issue 7 2010Rosalyn J. Singleton Abstract Respiratory syncytial virus (RSV) in Alaska Native children from the Yukon Kuskokwim (YK) Delta is associated with a hospitalization rate five times higher than that reported for the general US child population. The role of other viral respiratory pathogens has not been studied in this population. YK Delta children <3 years of age hospitalized with respiratory infections and same aged community control children were prospectively enrolled between October 2005 and September 2007. Polymerase chain reaction detection of viruses was performed on nasopharyngeal samples. Characteristics of hospitalized and asymptomatic control children were analyzed. From October 2005 to September 2007, 440 hospitalized and 425 control children were analyzed. Respiratory viruses were detected in 90% (395) of hospitalized children: 194 (44%) rhinovirus, 131 (30%) adenovirus, 102 (23%) RSV, 77 (18%) para influenza viruses (PIV), 66 (15%) human metapneumovirus (hMPV), 23 (5%) influenza, and 25 (6%) coronavirus. Fifty-two percent (221) of control children had a virus detected, most commonly rhinovirus (33%), and adenovirus (16%). RSV, PIV, hMPV, and influenza were significantly more common in hospitalized cases than control children, but rhinovirus, adenovirus, and coronavirus were not. RSV and hMPV were associated with higher severity of illness. In this study, RSV remains the most important virus associated with respiratory hospitalization, although hMPV and PIV were also common. RSV and hMPV were associated with more severe illness. Rhinovirus and adenovirus were detected in two-thirds of hospitalized children, but their frequent detection in control children made their role in respiratory hospitalization uncertain. J. Med. Virol. 82:1282,1290, 2010. © 2010 Wiley-Liss, Inc. [source] Frequency of 530-bp deletion in Actinobacillus actinomycetemcomitans leukotoxin promoter regionMOLECULAR ORAL MICROBIOLOGY, Issue 5 2000A. Contreras Actinobacillus actinomycetemcomitans strains showing a 530-bp deletion in the promoter region of the leukotoxin gene operon elaborate high amounts of leukotoxin that may play a role in the pathogenesis of periodontal disease. This study used polymerase chain reaction detection to determine the occurrence of the 530-bp deletion in 94 A. actinomycetemcomitans strains from individuals of various ethnic backgrounds. Eleven blacks and one Hispanic subject but no Caucasian or Asian subjects showed the 530-bp deletion in the leukotoxin promoter region, suggesting that the deletion is mainly a characteristic of individuals of African descent. A. actinomycetemcomitans strains exhibiting a deletion in the leukotoxin promotor region occurred both in individuals having severe periodontitis and in adolescents revealing no evidence of destructive periodontal disease. [source] Detection of human herpesvirus-6 in cerebrospinal fluid of patients with encephalitis,ANNALS OF NEUROLOGY, Issue 3 2009Karen Yao MS Objective Virus infections are the most common causes of encephalitis, a syndrome characterized by acute inflammation of the brain. More than 150 different viruses have been implicated in the pathogenesis of encephalitis; however, because of limitations with diagnostic testing, causative factors of more than half of the cases remain unknown. Methods To investigate whether human herpesvirus-6 (HHV-6) is a causative agent of encephalitis, we examined for evidence of virus infection by determining the presence of viral sequence using polymerase chain reaction and assessed HHV-6 antibody reactivity in the cerebrospinal fluid of encephalitis patients with unknown cause. In a cohort study, we compared virus-specific antibody levels in cerebrospinal fluid samples of patients with encephalitis, relapsing-remitting multiple sclerosis, and other neurological diseases. Results Our results demonstrated increased levels of HHV-6 IgG, as well as IgM levels, in a subset of encephalitis patients compared with other neurological diseases. Moreover, cell-free viral DNA that is indicative of active infection was detected in 40% (14/35) of encephalitis patients, whereas no amplifiable viral sequence was found in either relapsing-remitting MS or other neurological diseases patients. In addition, a significant correlation between polymerase chain reaction detection and anti-HHV-6 antibody response was also demonstrated. Interpretation Collectively, these results suggested HHV-6 as a possible pathogen in a subset of encephalitis cases. Ann Neurol 2009;65:257,267 [source] | ||||||||||