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Clearance of circulating fetal DNA in maternal plasma after delivery has been studied using quantitative PCR analysis of the sex-determining region Y gene as a marker for male fetuses. Plasma samples from 12 women were analyzed 1-42 days after males were born. The mean half-life for circulating fetal DNA was 16.3 min, the range being 4-30 min. Plasma DNA analysis may be less susceptible to false-positive results due to carryover from other pregnancies than detection of fetal cells in maternal blood. The quick clearance may be useful for monitoring feto-maternal events that occur rapidly.

A real-time method for quantitative PCR assay of the concentration of fetal DNA in maternal serum and plasma has been developed. There are implications for noninvasive prenatal diagnosis. Fetal DNA has now been shown to be in high concentrations in maternal plasma and it can be detected in the seventh gestational week. Concentration increases as the pregnancy goes on.

Background: Sore throat is a common condition caused by viruses or bacteria, and is a leading cause of antibiotic prescription in primary care. The most common bacterial species is group A streptococcus ('strep throat'). Between 50% to 70% of pharyngitis cases are treated with antibiotics, despite the majority of cases being viral in origin. One strategy to reduce antibiotics is to use rapid tests for group A streptococcus to guide antibiotic prescriptions. Rapid tests can be used alone or in combination with a clinical scoring system., Objectives: To assess the efficacy and safety of strategies based on rapid tests to guide antibiotic prescriptions for sore throat in primary care settings., Search Methods: We searched CENTRAL, MEDLINE, Embase, CINAHL, Web of Science, and LILACS, as well as the trial registries ClinicalTrials.gov and the WHO ICTRP on 5 June 2019., Selection Criteria: We included randomised controlled trials (RCTs) comparing rapid tests with management based on clinical grounds to guide the prescription of antibiotics for people with a sore throat in ambulatory care settings. We included trials that randomised individuals, as well as cluster-RCTs in which individual practitioners (or practices) or emergency departments were randomised., Data Collection and Analysis: Two review authors independently extracted data on the primary outcomes (number of participants provided with an antibiotic prescription; number of participants with an antibiotic dispensed) and secondary outcomes (duration of sore throat symptoms; duration of other symptoms; quality of life measures; number of participants with a complication attributed to the index infection; number of participants in need of re-consultation by the end of follow-up; number of participants in need of hospital admission by the end of follow-up; number of satisfied participants; number of participants with an adverse event attributed to the rapid test). We assessed the risk of bias of all included trials and used GRADE to assess the certainty of the evidence. We performed meta-analyses and sensitivity analyses when feasible., Main Results: We included five trials (2891 children and adult participants in total; 2545 participants after adjusting for clustering). Management in the intervention group was as follows: in three trials rapid tests were used in combination with a clinical scoring system; in one trial, some physicians were asked to use rapid tests alone, while others were asked to use rapid tests in combination with a clinical scoring system; in one trial, rapid tests were used alone. Based on data from five trials (2545 participants), a large reduction in prescribed antibiotics was found in the rapid test group (481/1197) versus management based on clinical grounds (865/1348), for a summary risk difference (RD) of -25%, 95% confidence interval (CI) -31% to -18%; I 2 = 62%; moderate-certainty evidence. Estimates of effect on antibiotic prescription rates were stable in various sensitivity analyses. Based on data from two trials (900 people) originating from the same overarching study, the evidence suggests that rapid tests may not reduce dispensed antibiotic treatments: rapid test group (156/445) versus management based on clinical grounds (197/455); summary RD -7%, 95% CI -17% to 2%; I 2 = 53%; low-certainty evidence. Four trials (2075 participants) reported data on the number of participants with a complication attributed to the index infection; the summary odds ratio (OR) was 0.85, 95% CI 0.03 to 26.65; P = 0.93; I 2 = 62%; very low-certainty evidence, which means that people in the rapid testing group were less likely to develop complications of the index infection, but the evidence is very uncertain. Two trials (1161 participants) reported on the number of participants in need of re-consultation by the end of follow-up; the summary OR was 1.12, 95% CI 0.57 to 2.21; P = 0.74; I 2 = 59%; low-certainty evidence, which means that participants in the rapid testing group were more likely to be in need of re-consultation by the end of the study follow-up, but the evidence is uncertain. Lack of data impeded assessment of other secondary outcomes (including safety outcomes) and of sources of heterogeneity.  AUTHORS' CONCLUSIONS: Rapid testing to guide antibiotic treatment for sore throat in primary care probably reduces antibiotic prescription rates by 25% (absolute risk difference), but may have little or no impact on antibiotic dispensing. More studies are needed to assess the efficacy and safety of rapid test-guided antibiotic prescribing, notably to evaluate patient-centred outcomes and variability across subgroups (e.g. adults versus children)., (Copyright © 2020 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

Objective: Patients are increasingly seeking nonsurgical treatment for the aging face. The purpose of this study was to evaluate the clinical efficacy and outcomes of a thermistor-controlled subdermal skin tightening device (ThermiTight) as a treatment modality for the aging face., Methods: A retrospective analysis of 12 patients was completed on patients having undergone ThermiTight for midface and neck skin tightening. Only five patients had a greater than 1 year follow-up and were included in the study. Two blinded reviewers assessed photographs taken pre-procedure and 1 year post-procedure using a standardized skin laxity scale. Patient charts were reviewed to assess for complications up to 12 months post-treatment., Results: The mean age of included patients was 57 years, and all five patients were female. One (20%) patient treated with ThermiTight was also treated with injectables (Botox, Juvéderm) simultaneously. One (20%) patient developed a wound complication. One (20%) patient complained of incisional site pain at her first postoperative visit that subsequently self-resolved. On a five-point scale to assess facial skin laxity, there was an average improved score of 0.85 per patient ( P < .001) at one year post-procedure. Two blinded reviewers correctly categorized photographs as either being "baseline" or "post-procedure" 100% of the time. There was no significant difference between the skin laxity scores by the blinded reviewers ( P = .05)., Conclusion: ThermiTight is a new technology used for nonsurgical treatment of the aging face. Long-term outcomes demonstrate the safety and efficacy of the procedure. Complications are rare, but possible, in the use of ThermiTight. Level of Evidence: 3.

Recommendations to guide parents' symptomatic management of febrile illnesses in children have been published in many countries. The lack of systematic appraisal of parents' knowledge and behaviors and their evolution over time precludes an analysis of their impact and identification of targets for future educational messages. We systematically searched for studies published between 1980 and 2016 that reported a quantitative evaluation of knowledge and behaviors of >50 parents for managing fever in children. We used MEDLINE and tracked related articles, citations and co-authors personal files. Study selection and data extraction were independently performed by two reviewers. For each item of knowledge and behaviors, we calculated mean frequencies during the first and last quinquennials of the studied period and assessed temporal trends with inverse-variance weighted linear regression of frequencies over years. We observed substantial methodological heterogeneity among the 62 included articles (64 primary studies, 36,791 participants, 30 countries) that met inclusion criteria. Statistically significant changes over time were found in the use of rectal (98 to 4%) and axillary temperature measurement (1-19%), encouraging fluid intake (19-62%), and use of acetylsalicylic acid (60 to 1%). No statistically significant change was observed for the accurate definition of fever (38-55%), or the use of acetaminophen (91-92%) or ibuprofen (20-43%). Parents' knowledge and behaviors have changed over time but continue to show poor concordance with recommendations. Our study identified future targets for educational messages, including basic ones such as the definition of fever.

Myotonic dystrophy type 1 (DM1) is caused by expansion of a CTG triplet repeat in the 3' untranslated region of the DMPK gene that encodes a serine-threonine kinase. Patients with larger repeats tend to have a more severe phenotype. Clinical laboratories require reference and quality control materials for DM1 diagnostic and carrier genetic testing. Well-characterized reference materials are not available. To address this need, the Centers for Disease Control and Prevention-based Genetic Testing Reference Material Coordination Program, in collaboration with members of the genetic testing community, the National Registry of Myotonic Dystrophy and Facioscapulohumeral Muscular Dystrophy Patients and Family Members, and the Coriell Cell Repositories, has established and characterized cell lines from patients with DM1 to create a reference material panel. The CTG repeats in genomic DNA samples from 10 DM1 cell lines were characterized in three clinical genetic testing laboratories using PCR and Southern blot analysis. DMPK alleles in the samples cover four of five DM1 clinical categories: normal (5 to 34 repeats), mild (50 to 100 repeats), classical (101 to 1000 repeats), and congenital (>1000 repeats). We did not identify or establish Coriell cell lines in the premutation range (35 to 49 repeats). These samples are publicly available for quality control, proficiency testing, test development, and research and should help improve the accuracy of DM1 testing., (Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

The planning and installation of a telemedicine system for communication within a teaching hospital and its academic and hospital units with a capacity for accommodation of up to 400 video-stations is described. The system is intended for improving the communication between patients and health professionals, and between the health professionals themselves. It also provides the basis for improving pre-graduate teaching, especially problem-based learning, and all aspects of postgraduate teaching.

Recently, cell-free EBV DNA has been detected in the plasma and serum of patients with nasopharyngeal carcinoma (NPC). We studied the relationship between plasma/serum EBV DNA and tumor recurrence. Using real-time quantitative PCR, the median plasma EBV DNA concentration in 10 patients with tumor recurrence was determined to be 32,350 copies/ml, whereas that in 15 patients in continuous remission for a mean period of 2 years was 0 copy/ml. Longitudinal follow-up of 17 NPC patients revealed 6 individuals with tumor recurrence and 11 patients who remained in remission. Significant elevations in serum EBV DNA, sometimes up to 6 months before detectable clinical deterioration, were observed in the patients who subsequently developed tumor recurrence. Continuously low or undetectable levels of serum EBV DNA were observed in the patients who remained in remission. These results suggest that plasma/serum cell-free EBV DNA may be a valuable tool for the monitoring of NPC patients for the early detection of tumor recurrence.

We have developed a quantitative method for methylation analysis of the p16 gene based on real-time methylation-specific PCR (MSP). Real-time MSP is sensitive enough to detect down to 10 genome equivalents of the methylated p16 sequence. Application of real-time MSP to DNA from tumor-derived cell lines revealed complete concordance with conventional MSP analysis. Quantitative data generated by real-time MSP were expressed as the methylation index, which was defined as the percentage of bisulfite-converted DNA that consisted of methylated target sequences. The methylation index was shown to be inversely correlated with p16 gene transcription during demethylation treatment of cell lines with 5-aza-2'-deoxycytidine. The application of real-time MSP to bone marrow aspirates from patients with multiple myeloma revealed complete concordance with conventional MSP analysis. Real-time quantitative MSP may have applications in elucidating diverse biological processes involving DNA methylation and may become a valuable diagnostic tool for detecting tumor-associated epigenetic changes in cancer patients.

Using real-time quantitative PCR, cell-free EBV DNA was detectable in the plasma of 96% (55 of 57) of nasopharyngeal carcinoma (NPC) patients (median concentration, 21058 copies/ml) and 7% (3 of 43) of controls (median concentration, 0 copies/ml). Advanced-stage NPC patients had higher plasma EBV DNA levels than those with early-stage disease. At 1 month after completion of radiotherapy, plasma EBV DNA was undetectable in 7 of 15 subjects (47%) but remained high in the remaining 8 subjects (53%). Clinical examination revealed that all of the former seven subjects had complete tumor regression, whereas six of the eight latter subjects exhibited evidence of disease persistence or had developed distant metastases. These results suggest that quantitative analysis of plasma EBV DNA may be a useful clinical and research tool in the screening and monitoring of NPC patients.

We have studied the feasibility of detecting tumor-associated aberrant p16 methylation in the circulation of patients with hepatocellular carcinoma (HCC). We extracted DNA from the tumor tissues and peripheral blood plasma or serum of 22 HCC patients. p16 methylation was found in 73% (16 of 22) of HCC tissues using methylation-specific PCR. Among the 16 cases with aberrant methylation in the tumor tissues, similar changes were also detected in the plasma/serum samples of 81% (13 of 16) of the cases. No methylated p16 sequences were detected in the peripheral plasma/serum of the six HCC cases without these changes in the tumor, in 38 patients with chronic hepatitis/cirrhosis, or in 10 healthy control subjects. These results suggest that circulating liver tumor DNA may be detected using tumor-associated DNA methylation changes. Because methylation abnormalities have been found in many other genes and tumor types, this approach may have implications for the noninvasive detection of a wide variety of cancers.

Doctors have recently gained substantial experience of using telemedical applications for consultations, education and training, and conferences. What is still lacking is systematic evaluation of these new approaches compared with traditional procedures. Trials involving consultations for diagnostic, monitoring, and interpretative purposes should be blinded and multicentred, and should include tests of patient satisfaction as well as macro-economic considerations. The quality of educational programmes and conferences should be documented and compared with traditional teaching methods. International standards need to be developed for such evaluations, to allow comparisons between trials performed at national and international levels. Hong Kong is in a good position to contribute to these developments because of a well-integrated health care system and excellent telecommunication facilities. Through telemedicine, Hong Kong could resume a leading global position in the use of advanced information technology.

Glycogen storage disease type la (GSD1a) is an autosomal recessive metabolic disorder caused by a deficiency in glucose-6-phosphatase (G6Pase). We analyzed the G6Pase genes of two unrelated Chinese families with GSD1a. DNA sequencing of all five exons and the exon-intron boundaries revealed a G T transversion at nucleotide 727 (727G-->T) in exon 5, which has previously been reported to cause abnormal splicing. In one family, the subject and her affected sister were confirmed to be homozygous for this mutation and their parents to be heterozygotes. In the other family, the proband was identified to be heterozygous for this mutation, and a novel mutation, the 341delG in exon 2, was identified. This mutation alters the reading frame and creates a stop codon TAA 15 codons downstream from the mutation, resulting in a truncated protein. Family studies revealed that the father was heterozygous for the 727G-->T mutation and that the mother was heterozygous for the 341delG mutation. This is the first time that the 727G T mutation has been found in Chinese patients or outside Japan. Since we only tested two GSD1a families and found 727G-->T in both, we believe that this mutation may also be prevalent in our local Chinese population. To investigate allele frequencies, we screened 385 Chinese healthy volunteers and found two asymptomatic carriers. Our findings suggest that the 727G-->T mutation is indeed prevalent in Hong Kong.