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PhytoKeys 2023was confirmed as polyphyletic by recent phylogenetic analyses, with Chinese species of distantly related to those from Japan. Among the Chinese species of , is a...
was confirmed as polyphyletic by recent phylogenetic analyses, with Chinese species of distantly related to those from Japan. Among the Chinese species of , is a morphologically unique as well as taxonomically problematic species endemic to South China, of which the generic designation is still uncertain. Molecular analyses based on both plastid and nuclear genomic data demonstrated that this species is closest to the recently published genus . Morphologically, the two are somewhat similar to each other in flowering branches developing at the nodes of every order of branches, raceme-like units of inflorescence with 3-5 short spikelets, each spikelet with few florets including a rudimentary one at the apex, and each floret with 3 stamens and 2 stigmas. However, is very different from species in many reproductive and vegetative characters, such as the morphology of paracladia (lateral spikelet "pedicels"), the absence or existence of pulvinus at the base of paracladia, the relative length of the upper glume and the lowest lemma, the shape of lodicules and primary culm buds, the branch complement, the morphology of nodes, culm leaves and dried foliage leaf blades, and the number of foliage leaves per ultimate branchlet. The morphological and molecular evidence warrants recognition of a new genus to accommodate this unique species, which is here named . After consulting related literature and examination of herbarium specimens or specimen photos, a taxonomic revision of and its synonyms was made, and it was confirmed that four names, viz. , , and , should be merged with , while and are distinct species.
PubMed: 37250355
DOI: 10.3897/phytokeys.221.98920 -
Journal of Mass Spectrometry and... Apr 2023Determination of folate insufficiency is of considerable interest given its importance in fetal development and red blood cell formation; however, access to blood tests...
INTRODUCTION
Determination of folate insufficiency is of considerable interest given its importance in fetal development and red blood cell formation; however, access to blood tests may be limited due to the requirement for phlebotomy as well as controlled temperature shipping of blood specimens to laboratories for testing due to the inherent instability of folate and its vitamers.
METHODS
An LC-MS/MS test was developed and validated for the measurement of 5-methyltetrahydrofolate (5MTHF) in dried plasma specimens collected from fingerstick blood using a laminar flow blood separation device, as well as liquid venous plasma for comparison. Two pre-analytical factors investigated influencing the measurement of 5MTHF in dried plasma were hemolysis of the fingerstick blood during collection and storage/shipment of the dried plasma.
RESULTS
Although observed infrequently, hemolysis >10 % resulted in elevated 5MTHF measurements, but hemolysis >1 % resulted in elevated chloride measurements, which were necessary to normalize 5MTHF measurements for variation in volume of dried plasma specimens. Stability of 5MTHF was improved in dried plasma relative to liquid plasma at ambient temperatures, but not sufficiently to allow for uncontrolled temperature shipping despite controlling for humidity and light exposure. Shipping studies emulating ISTA procedure 7D were conducted with a reusable cold packaging solution. The packaging failed to stabilize 5MTHF in dried plasma specimens during a 2-day summer shipping evaluation, but did provide sufficient temperature control to stabilize 5MTHF during the overnight shipping evaluation.
CONCLUSION
Our studies provide boundary conditions with respect to hemolysis, storage, and shipping for successful analysis of 5MTHF from dried plasma specimens.
PubMed: 36741267
DOI: 10.1016/j.jmsacl.2023.01.003 -
The New England Journal of Medicine Jun 2011Congenital cytomegalovirus (CMV) infection is an important cause of hearing loss, and most infants at risk for CMV-associated hearing loss are not identified early in... (Clinical Trial)
Clinical Trial
BACKGROUND
Congenital cytomegalovirus (CMV) infection is an important cause of hearing loss, and most infants at risk for CMV-associated hearing loss are not identified early in life because of failure to test for the infection. The standard assay for newborn CMV screening is rapid culture performed on saliva specimens obtained at birth, but this assay cannot be automated. Two alternatives--real-time polymerase-chain-reaction (PCR)-based testing of a liquid-saliva or dried-saliva specimen obtained at birth--have been developed.
METHODS
In our prospective, multicenter screening study of newborns, we compared real-time PCR assays of liquid-saliva and dried-saliva specimens with rapid culture of saliva specimens obtained at birth.
RESULTS
A total of 177 of 34,989 infants (0.5%; 95% confidence interval [CI], 0.4 to 0.6) were positive for CMV, according to at least one of the three methods. Of 17,662 newborns screened with the use of the liquid-saliva PCR assay, 17,569 were negative for CMV, and the remaining 85 infants (0.5%; 95% CI, 0.4 to 0.6) had positive results on both culture and PCR assay. The sensitivity and specificity of the liquid-saliva PCR assay were 100% (95% CI, 95.8 to 100) and 99.9% (95% CI, 99.9 to 100), respectively, and the positive and negative predictive values were 91.4% (95% CI, 83.8 to 96.2) and 100% (95% CI, 99.9 to 100), respectively. Of 17,327 newborns screened by means of the dried-saliva PCR assay, 74 were positive for CMV, whereas 76 (0.4%; 95% CI, 0.3 to 0.5) were found to be CMV-positive on rapid culture. Sensitivity and specificity of the dried-saliva PCR assay were 97.4% (95% CI, 90.8 to 99.7) and 99.9% (95% CI, 99.9 to 100), respectively. The positive and negative predictive values were 90.2% (95% CI, 81.7 to 95.7) and 99.9% (95% CI, 99.9 to 100), respectively.
CONCLUSIONS
Real-time PCR assays of both liquid- and dried-saliva specimens showed high sensitivity and specificity for detecting CMV infection and should be considered potential screening tools for CMV in newborns. (Funded by the National Institute on Deafness and Other Communication Disorders.).
Topics: Bacteriological Techniques; Cytomegalovirus; Cytomegalovirus Infections; DNA, Viral; Female; Humans; Infant, Newborn; Male; Neonatal Screening; Polymerase Chain Reaction; Prospective Studies; Saliva
PubMed: 21631323
DOI: 10.1056/NEJMoa1006561 -
Advanced Science (Weinheim,... Sep 2021Blood cell analysis is a major pillar of biomedical research and healthcare. These analyses are performed in central laboratories. Rapid shipment from collection site to...
Blood cell analysis is a major pillar of biomedical research and healthcare. These analyses are performed in central laboratories. Rapid shipment from collection site to the central laboratories is currently needed because cells and biomarkers degrade rapidly. The dried blood spot from a fingerstick allows the preservation of cellular molecules for months but entire cells are never recovered. Here leucocyte elution is optimized from dried blood spots. Flow cytometry and mRNA expression profiling are used to analyze the recovered cells. 50-70% of the leucocytes that are dried on a polyester solid support via elution after shaking the support with buffer are recovered. While red blood cells lyse upon drying, it is found that the majority of leucocytes are preserved. Leucocytes have an altered structure that is improved by adding fixative in the elution buffer. Leucocytes are permeabilized, allowing an easy staining of all cellular compartments. Common immunophenotyping and mRNAs are preserved. The ability of a new biomarker (CD169) to discriminate between patients with and without Severe Acute Respiratory Syndrome induced by Coronavirus 2 (SARS-CoV-2) infections is also preserved. Leucocytes from blood can be dried, shipped, and/or stored for at least 1 month, then recovered for a wide variety of analyses, potentially facilitating biomedical applications worldwide.
Topics: Antibodies, Viral; Biomarkers; Blood Specimen Collection; COVID-19; Cell Separation; Communicable Diseases; Diagnostic Tests, Routine; Dried Blood Spot Testing; Erythrocytes; Flow Cytometry; Hematology; Humans; Immunophenotyping; Leukocytes; RNA, Messenger; SARS-CoV-2
PubMed: 34278739
DOI: 10.1002/advs.202100323 -
International Journal of Molecular... Dec 2022Miniaturisation and simplification are novel approaches in clinical bioanalysis, especially in therapeutic drug monitoring (TDM). These contemporary trends are related... (Review)
Review
Miniaturisation and simplification are novel approaches in clinical bioanalysis, especially in therapeutic drug monitoring (TDM). These contemporary trends are related to the sampling, pre-treatment, and analysis of biological fluids. Currently, dried blood spot (DBS), one of the most popular microsampling techniques, is feasible and inexpensive. However, obtaining reliable results with sample homogeneity and volume variability is difficult. Volumetric Absorptive Microsampling (VAMS) has recently enabled the accurate and precise collection of a fixed blood volume. It reduced the hematocrit effect, improved volumetric accuracy, and generated results correlating with the dose and drug exposure from wet blood. This review focuses on VAMS-Mitra™ devices, which have become increasingly important since 2014, mainly for TDM and toxicology studies. First, the current literature has been reviewed based on immunosuppressants and their determination in samples obtained using Mitra™. Second, the critical points, weaknesses, and strengths have been characterized in contrast to classic venipuncture and other microsampling methods. Finally, we indicate the points of attention according to the perspective of Mitra™ as well as its usefulness in clinical practice. VAMS is currently state-of-the-art in microsampling and seems to be a good instrument for improving adherence to immunosuppressive therapy, especially in the pediatric population.
Topics: Humans; Child; Blood Specimen Collection; Drug Monitoring; Dried Blood Spot Testing; Specimen Handling; Immunosuppressive Agents
PubMed: 36614123
DOI: 10.3390/ijms24010681 -
Annals of Epidemiology Sep 2020The U.S. response to the SARS-CoV-2 epidemic has been hampered by early and ongoing delays in testing for infection; without data on where infections were occurring and...
PURPOSE
The U.S. response to the SARS-CoV-2 epidemic has been hampered by early and ongoing delays in testing for infection; without data on where infections were occurring and the magnitude of the epidemic, early public health responses were not data-driven. Understanding the prevalence of SARS-CoV-2 infections and immune response is critical to developing and implementing effective public health responses. Most serological surveys have been limited to localities that opted to conduct them and/or were based on convenience samples. Moreover, results of antibody testing might be subject to high false positive rates in the setting of low prevalence of immune response and imperfect test specificity.
METHODS
We will conduct a national serosurvey for SARS-CoV-2 PCR positivity and immune experience. A probability sample of U.S. addresses will be mailed invitations and kits for the self-collection of anterior nares swab and finger prick dried blood spot specimens. Within each sampled household, one adult 18 years or older will be randomly selected and asked to complete a questionnaire and to collect and return biological specimens to a central laboratory. Nasal swab specimens will be tested for SARS-CoV-2 RNA by RNA PCR; dried blood spot specimens will be tested for antibodies to SARS-CoV-2 (i.e., immune experience) by enzyme-linked immunoassays. Positive screening tests for antibodies will be confirmed by a second antibody test with different antigenic basis to improve predictive value of positive (PPV) antibody test results. All persons returning specimens in the baseline phase will be enrolled into a follow-up cohort and mailed additional specimen collection kits 3 months after baseline. A subset of 10% of selected households will be invited to participate in full household testing, with tests offered for all household members aged ≥3 years. The main study outcomes will be period prevalence of infection with SARS-CoV-2 and immune experience, and incidence of SARS-CoV-2 infection and antibody responses.
RESULTS
Power calculations indicate that a national sample of 4000 households will facilitate estimation of national SARS-CoV-2 infection and antibody prevalence with acceptably narrow 95% confidence intervals across several possible scenarios of prevalence levels. Oversampling in up to seven populous states will allow for prevalence estimation among subpopulations. Our 2-stage algorithm for antibody testing produces acceptable PPV at prevalence levels ≥1.0%. Including oversamples in states, we expect to receive data from as many as 9156 participants in 7495 U.S. households.
CONCLUSIONS
In addition to providing robust estimates of prevalence of SARS-CoV-2 infection and immune experience, we anticipate this study will establish a replicable methodology for home-based SARS-CoV-2 testing surveys, address concerns about selection bias, and improve positive predictive value of serology results. Prevalence estimates of SARS-CoV-2 infection and immune experience produced by this study will greatly improve our understanding of the spectrum of COVID-19 disease, its current penetration in various demographic, geographic, and occupational groups, and inform the range of symptoms associated with infection. These data will inform resource needs for control of the ongoing epidemic and facilitate data-driven decisions for epidemic mitigation strategies.
Topics: Betacoronavirus; COVID-19; COVID-19 Testing; Clinical Laboratory Techniques; Clinical Trial Protocols as Topic; Coronavirus; Coronavirus Infections; Disease Outbreaks; Humans; Pandemics; Pneumonia, Viral; RNA, Viral; SARS-CoV-2
PubMed: 32791199
DOI: 10.1016/j.annepidem.2020.07.015 -
Journal of Clinical Microbiology Jan 2013Dried blood spots (DBS) collected onto filter paper have eased the difficulty of blood collection in resource-limited settings. Currently, Whatman 903 (W-903) filter... (Comparative Study)
Comparative Study
Comparison of Ahlstrom grade 226, Munktell TFN, and Whatman 903 filter papers for dried blood spot specimen collection and subsequent HIV-1 load and drug resistance genotyping analysis.
Dried blood spots (DBS) collected onto filter paper have eased the difficulty of blood collection in resource-limited settings. Currently, Whatman 903 (W-903) filter paper is the only filter paper that has been used for HIV load and HIV drug resistance (HIVDR) testing. We therefore evaluated two additional commercially available filter papers, Ahlstrom grade 226 (A-226) and Munktell TFN (M-TFN), for viral load (VL) testing and HIVDR genotyping using W-903 filter paper as a comparison group. DBS specimens were generated from 344 adult patients on antiretroviral therapy (ART) in Botswana. The VL was measured with NucliSENS EasyQ HIV-1 v2.0, and genotyping was performed for those specimens with a detectable VL (≥ 2.90 log(10) copies/ml) using an in-house method. Bland-Altman analysis revealed a strong concordance in quantitative VL analysis between W-903 and A-226 (bias = -0.034 ± 0.246 log(10) copies/ml [mean difference ± standard deviation]) and W-903 and M-TFN (bias = -0.028 ± 0.186 log(10) copies/ml) filter papers, while qualitative VL analysis for virological failure determination, defined as a VL of ≥ 3.00 log(10) copies/ml, showed low sensitivities for A-266 (71.54%) and M-TFN (65.71%) filter papers compared to W-903 filter paper. DBS collected on M-TFN filter paper had the highest genotyping efficiency (100%) compared to W-903 and A-226 filter papers (91.7%) and appeared more sensitive in detecting major HIVDR mutations. DBS collected on A-226 and M-TFN filter papers performed similarly to DBS collected on W-903 filter paper for quantitative VL analysis and HIVDR detection. Together, the encouraging genotyping results and the variability observed in determining virological failure from this small pilot study warrant further investigation of A-226 and M-TFN filter papers as specimen collection devices for HIVDR monitoring surveys.
Topics: Adult; Botswana; Desiccation; Genotype; HIV Infections; HIV-1; Humans; Microbial Sensitivity Tests; Pilot Projects; Sensitivity and Specificity; Specimen Handling; Viral Load
PubMed: 23077127
DOI: 10.1128/JCM.02002-12 -
PLoS Medicine Aug 2022Accurate routine HIV viral load testing is essential for assessing the efficacy of antiretroviral treatment (ART) regimens and the emergence of drug resistance. While... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Accurate routine HIV viral load testing is essential for assessing the efficacy of antiretroviral treatment (ART) regimens and the emergence of drug resistance. While the use of plasma specimens is the standard for viral load testing, its use is restricted by the limited ambient temperature stability of viral load biomarkers in whole blood and plasma during storage and transportation and the limited cold chain available between many health care facilities in resource-limited settings. Alternative specimen types and technologies, such as dried blood spots, may address these issues and increase access to viral load testing; however, their technical performance is unclear. To address this, we conducted a meta-analysis comparing viral load results from paired dried blood spot and plasma specimens analyzed with commonly used viral load testing technologies.
METHODS AND FINDINGS
Standard databases, conferences, and gray literature were searched in 2013 and 2018. Nearly all studies identified (60) were conducted between 2007 and 2018. Data from 40 of the 60 studies were included in the meta-analysis, which accounted for a total of 10,871 paired dried blood spot:plasma data points. We used random effects models to determine the bias, accuracy, precision, and misclassification for each viral load technology and to account for between-study variation. Dried blood spot specimens produced consistently higher mean viral loads across all technologies when compared to plasma specimens. However, when used to identify treatment failure, each technology compared best to plasma at a threshold of 1,000 copies/ml, the present World Health Organization recommended treatment failure threshold. Some heterogeneity existed between technologies; however, 5 technologies had a sensitivity greater than 95%. Furthermore, 5 technologies had a specificity greater than 85% yet 2 technologies had a specificity less than 60% using a treatment failure threshold of 1,000 copies/ml. The study's main limitation was the direct applicability of findings as nearly all studies to date used dried blood spot samples prepared in laboratories using precision pipetting that resulted in consistent input volumes.
CONCLUSIONS
This analysis provides evidence to support the implementation and scale-up of dried blood spot specimens for viral load testing using the same 1,000 copies/ml treatment failure threshold as used with plasma specimens. This may support improved access to viral load testing in resource-limited settings lacking the required infrastructure and cold chain storage for testing with plasma specimens.
Topics: Dried Blood Spot Testing; HIV Infections; HIV-1; Humans; RNA, Viral; Sensitivity and Specificity; Viral Load
PubMed: 35994520
DOI: 10.1371/journal.pmed.1004076 -
Journal of Photochemistry and... Apr 2021Worldwide shortages of personal protective equipment during COVID-19 pandemic has forced the implementation of methods for decontaminating face piece respirators such as...
Worldwide shortages of personal protective equipment during COVID-19 pandemic has forced the implementation of methods for decontaminating face piece respirators such as N95 respirators. The use of UV irradiation to reduce bioburden of used respirators attracts attention, making proper testing protocols of uttermost importance. Currently artificial saliva is used but its comparison to human saliva from the UV disinfection perspective is lacking. Here we characterize UV spectra of human and artificial saliva, both fresh and after settling, to test for possible interference for UV-based disinfection. ASTM 2720 artificial saliva recipe (with either porcine or bovine mucin) showed many discrepancies from average (N = 18) human saliva, with different mucins demonstrating very different UV absorbance spectra, resulting in very different UV transmittance at different wavelength. Reducing porcine mucin concentration from 3 to 1.7 g/L brought UVA in the artificial saliva to that of average human saliva (although not for other wavelengths), allowing 254 nm disinfection experiments. Phosphate saline and modified artificial saliva were spiked with 8.6 log CFU/ml B. subtilis spores (ATCC 6633) and irradiated at dose of up to 100 mJ/cm, resulting in 5.9 log inactivation for a saline suspension, and 2.8 and 1.1 log inactivation for ASTM-no mucin and ASTM-1.7 g/L porcine mucin 2 μL dried droplets, respectively. UVC irradiation of spores dried in human saliva resulted in 2.3 and 1.5 log inactivation, depending on the size of the droplets (2 vs 10 μL, respectively) dried on a glass surface. Our results suggest that in the presence of the current standard dried artificial saliva it is unlikely that UVC can achieve 6 log inactivation of B. subtilis spores using a realistic UV dose (e.g. less than 2 J/cm) and the ATSM saliva recipe should be revised for UV decontamination studies.
Topics: Animals; Bacillus subtilis; Canada; Cattle; Decontamination; Disinfection; Female; Humans; Israel; Male; Mucins; N95 Respirators; Saliva; Specimen Handling; Spectrophotometry, Ultraviolet; Spores, Bacterial; Ultraviolet Rays
PubMed: 33714723
DOI: 10.1016/j.jphotobiol.2021.112168 -
Indian Journal of Pharmacology 2017Benzodiazepines (BZD) are widely prescribed to substance users. However, the nonmedical use of prescription BZD often leads to abuse and dependence. Therefore, it is...
BACKGROUND AND AIM
Benzodiazepines (BZD) are widely prescribed to substance users. However, the nonmedical use of prescription BZD often leads to abuse and dependence. Therefore, it is important to detect BZD among substance users seeking treatment. The aim of the present study was to develop an efficient method for testing BZD on dried urine spot (DUS) and evaluating its clinical applicability.
METHODS
This involved optimization of conditions for the detection, recovery, and stability of BZD from dried urine, spotted on filter paper. Enzyme linked immuno-sorbent assay was used for screening whereas confirmation was done by gas chromatography. For clinical applicability, urine samples of BZD users were tested.
RESULTS
The recovery was found to be 99.7% in de-ionized water from 20 μl spotted urine samples. Limit of detection, inter-day and intra-day CV were found to be 100 ng/ml, 4.22% and 3.83%, respectively. BZD were found stable in DUS for 3 weeks at room temperature, and for 3 months at 4°C and -20°C. All the urine samples of benzodiazepine users were found positive by conventional method as well as the DUS method.
CONCLUSION
DUS method proved to be efficient for BZD testing with advantages of ease of collection, transportation, minimal invasiveness and small sample volume. It offers a useful alternative for BZD testing especially in developing countries where logistics of sample collection and transportation could be an important concern.
Topics: Benzodiazepines; Chromatography, Gas; Drug Stability; Enzyme-Linked Immunosorbent Assay; Humans; Limit of Detection; Male; Reproducibility of Results; Specimen Handling; Substance Abuse Detection; Substance-Related Disorders
PubMed: 29674802
DOI: 10.4103/ijp.IJP_578_16