bluuebunny/crossref_metadata_2025 huggingface dataset:
Validation of Sixteen Leukemia and Lymphoma Cell Lines as Controls for Molecular Gene Rearrangement Assays
Authors: Yao Rong , Rich Steven A , Schneider Erasmus
Published: July 2020

Background: Assays for rearrangement of the immunoglobulin, T-cell receptor, bcr/abl, and bcl-2 genes are valuable tools to aid in the diagnosis of leukemias and lymphomas and are now offered by many pathology laboratories. However, there is a lack of well-characterized and validated calibrators and positive controls for these assays. We therefore evaluated 16 readily available leukemia and lymphoma cell lines for their potential use as controls.

Methods: DNA and RNA were isolated from each cell line and analyzed by Southern blot and PCR or reverse transcription-PCR (RT-PCR). Rearrangements in the IgJH, IgJκ, TcR-β or TcR-γ, bcr/abl, and bcl-2 genes were detected by commercially available probes and primers. Cell lineages were confirmed by immunophenotyping.

Results: Immunoglobulin and T-cell receptor gene rearrangements were identified in five B- and three T-cell lines, respectively. Two cell lines tested positive for the bcr/abl gene, and one was positive for the bcl-2 gene rearrangement by Southern blot.

Conclusions: The 16 cell lines studied can be used as positive controls in molecular detection assays for gene rearrangements. The parallel processing of these cell lines with clinical samples can serve to quality control the experimental procedures from the first step of DNA or RNA extraction to the final step of result analysis.
Successful treatment of acute heart failure in COVID-19-induced cytokine storm with tocilizumab: a case report
Authors: Chitturi Kalyan R , Thacker Sameer , Al-Saadi Mukhtar A , Kassi Mahwash
Published: July 2020

Background

SARS-CoV-2 is known to induce a cytokine storm, a hyperinflammatory state driven by up-regulation of interleukin 6 (IL-6) and immunomodulatory chemokines that may result in acute heart failure.

Case summary

A 65-year-old woman with confirmed SARS-CoV-2 developed shock with multiorgan system failure, including acute biventricular heart failure, 2 weeks after the initial onset of fever, cough, and shortness of breath. The patient experienced myocardial recovery within 48 h after administration of tocilizumab, a humanized monoclonal anti-IL-6 receptor antibody, and multiple supportive vasoactive medications.

Discussion

The differential diagnosis of acute heart failure in critically ill patients with COVID-19 infection is broad, including sepsis-induced cardiomyopathy, Takotsubo syndrome, viral lymphocytic myocarditis, and acute coronary syndrome. Immunomodulatory treatment with tocilizumab may benefit patients who develop cardiogenic shock associated with SARS-CoV-2-induced cytokine storm.
6126Peripheral aneurysms in Marfan patients are common and are related to age and advanced aortic disease
Authors: Mila L , Teixido Tura G , Granato C , Limeres J , Servato L , Lopez-Sainz A , Gutierrez L , Galian L , Gonzalez-Alujas T , Rodriguez-Palomares J , Evangelista A
Published: July 2020

Background

Peripheral aneurysms are not included in the diagnostic criteria for Marfan syndrome (MFS); however, their real prevalence in MFS is unknown. Furthermore, they are commonly seen in other genetic entities such as Loeys-Dietz syndrome.

We aimed to investigate the prevalence of peripheral aneurysm in Marfan syndrome.

Methods

Patients with clinical criteria of Marfan syndrome and identified FBN1 mutation were evaluated. Only patients with either MRI or CT angiography assessing peripheral vessels were included in this study. MRI and CT angiography studies were retrospectively evaluated to detect the presence of peripheral aneurysms. Aortic dissection-related arterial dilations were excluded. Aortic events and those related to aneurysm complications were collected during follow-up.

Results

Two hundred and nine patients with Marfan and FBN1 mutation were evaluated. Of these 136 (65.1%) had undergone either MRA or CTA with peripheral artery study during follow-up. Mean age at the last follow-up visit was 42.4±14.1yrs; 54.4% were men, and mean follow-up 7.3±3.1 years. Sixty-six aneurysms were identified in 42 (30.9%) patients. The most common locations were the iliac arteries in 23. The rest were: renal (7), vertebral (5), splenic (5), coeliac (3), brachiocephalic (1), subclavian (3), carotid (3), axillary (2), internal mammary (3), femoral (2), hypogastric (3), bronchial (2), coronary (1), hepatic (1), lumbar (1), gastroduodenal (1) and popliteal (1). Twenty-six patients (61.9%) had more than one peripheral aneurysm, and only 4 required surgery.

Patients with peripheral aneurysms were older (47.2±14.3yrs vs 40.2±13.6yrs, p=0.06) and more frequently men (69.0% vs 47.9% p=0.026). Although patients with peripheral aneurysms did not more frequently have aortic dissection (16.7% vs 17.0%, p=0.586), they did more frequently have aortic surgery (73.8% vs 47.9% p=0.05).

Conclusions

Peripheral aneurysms are present in one third of Marfan syndrome patients and are related to age and more advanced aortic disease. Systematic use of whole-body vascular assessment in Marfan patients can provide a comprehensive evaluation of the entire arterial system, identifying other sites of vascular involvement at risk of potential complications, and the subgroup of patients with more aggressive vascular disease expression.
Membrane transporters in the bioproduction of organic acids: state of the art and future perspectives for industrial applications
Authors: Soares-Silva I , Ribas D , Sousa-Silva M , Azevedo-Silva J , Rendulić T , Casal M
Published: July 2020

Organic acids such as monocarboxylic acids, dicarboxylic acids or even more complex molecules such as sugar acids, have displayed great applicability in the industry as these compounds are used as platform chemicals for polymer, food, agricultural and pharmaceutical sectors. Chemical synthesis of these compounds from petroleum derivatives is currently their major source of production. However, increasing environmental concerns have prompted the production of organic acids by microorganisms. The current trend is the exploitation of industrial biowastes to sustain microbial cell growth and valorize biomass conversion into organic acids. One of the major bottlenecks for the efficient and cost-effective bioproduction is the export of organic acids through the microbial plasma membrane. Membrane transporter proteins are crucial elements for the optimization of substrate import and final product export. Several transporters have been expressed in organic acid-producing species, resulting in increased final product titers in the extracellular medium and higher productivity levels. In this review, the state of the art of plasma membrane transport of organic acids is presented, along with the implications for industrial biotechnology.
More Vulnerable? The Life Story Approach Highlights Older People’s Potential for Strength During the Pandemic
Authors: Lind Majse , Bluck Susan , McAdams Dan P
Published: July 2020

Objectives

Older adults have repeatedly been referred to as more physically vulnerable during the COVID-19 pandemic. The pandemic, however, is not only about becoming physically ill. It has many psychosocial aspects: people are exposed to myriad life challenges. The life story approach does not ignore physical status but also emphasizes psychosocial strengths. It highlights that older people are likely to have developed resilience through experiencing life challenges and living across history.

Method

We used the narrative method to review research on three strengths: tendency toward life reflection, adaptive use of personal memory, and temporal focus encouraging generativity.

Results

For each, we (a) present evidence that this strength manifests in the second half of life, and (b) identify how it may specifically be applied in dealing with the challenges of the pandemic. In considering their life stories, the picture that emerges is one of older adults as having the potential to show considerable psychosocial strength despite the adversities of the pandemic.

Discussion

We conclude that during this period of sweeping change in the lives of individuals of all ages, our older citizens may act as valuable societal anchors.
AXL Is a Potential Target for the Treatment of Intestinal Fibrosis
Authors: Steiner Calen A , Rodansky Eva S , Johnson Laura A , Berinstein Jeffrey A , Cushing Kelly C , Huang Sha , Spence Jason R , Higgins Peter D R
Published: July 2020

Background

Fibrosis is the final common pathway to intestinal failure in Crohn’s disease, but no medical therapies exist to treat intestinal fibrosis. Activated myofibroblasts are key effector cells of fibrosis in multiple organ systems, including the intestine. AXL is a receptor tyrosine kinase that has been implicated in fibrogenic pathways involving myofibroblast activation. We aimed to investigate the AXL pathway as a potential target for the treatment of intestinal fibrosis.

Methods

To establish proof of concept, we first analyzed AXL gene expression in 2 in vivo models of intestinal fibrosis and 3 in vitro models of intestinal fibrosis. We then tested whether pharmacological inhibition of AXL signaling could reduce fibrogenesis in 3 in vitro models of intestinal fibrosis. In vitro testing included 2 distinct cell culture models of intestinal fibrosis (matrix stiffness and TGF-β1 treatment) and a human intestinal organoid model using TGF-β1 cytokine stimulation.

Results

Our findings suggest that the AXL pathway is induced in models of intestinal fibrosis. We demonstrate that inhibition of AXL signaling with the small molecule inhibitor BGB324 abrogates both matrix-stiffness and transforming growth factor beta (TGF-β1)–induced fibrogenesis in human colonic myofibroblasts. AXL inhibition with BGB324 sensitizes myofibroblasts to apoptosis. Finally, AXL inhibition with BGB324 blocks TGF-β1-induced fibrogenic gene and protein expression in human intestinal organoids.

Conclusions

The AXL pathway is active in multiple models of intestinal fibrosis. In vitro experiments suggest that inhibiting AXL signaling could represent a novel approach to antifibrotic therapy for intestinal fibrosis such as in Crohn’s disease.
Injury Characteristics and Outcomes of Patients With Inflammatory Bowel Disease After Trauma: A Propensity Score Matched Analysis
Authors: Haac Bryce E , Nemirovsky Amy , Teeter William , Geyer Andrew , Birkett Richard T , Cross Raymond K , Engels Michael , Stein Deborah M , Bafford Andrea C
Published: July 2020

Background

The clinical course of patients with inflammatory bowel disease (IBD) after trauma is largely unknown. We sought to compare the clinical course of patients with IBD to those without.

Methods

We conducted a retrospective case-control study of adult patients admitted to a level-1 trauma center from January 1, 2008, through October 1, 2015. Seventy-five patients with IBD were identified. Cases were matched to controls by age, sex, injury severity, and mechanism using 4:1 propensity score-matching analysis. Injury characteristics, clinical course, and infectious and noninfectious complications were compared using bivariate and multivariate analysis.

Results

Participants had a mean age of 56 years and mean injury severity score of 15. Of the 75 cases, 44% had ulcerative colitis, 44% had Crohn’s disease, and 12% had undetermined type. More cases were on an immunosuppressant (19% vs 2%, P < 0.01) or steroids (8% vs 2%, P = 0.02) on admission compared with controls. More cases had prior abdominal surgery (P = 0.01). Cases had fewer brain injuries (P = 0.02) and higher admission Glasgow Coma Scale (P < 0.01) but required more neurosurgical intervention (P = 0.03). Cases required more orthopedic surgeries (P < 0.01) and more pain management consultations (P = 0.04). In multivariable analysis, IBD was associated with increased odds of operative intervention, pain management consultation, venous thromboembolism, and longer hospital stay (P < 0.05). Patients on immunosuppressants had increased odds of requiring surgery (P = 0.04), particularly orthopedic surgery (P < 0.01).

Conclusions

Baseline factors associated with inflammatory bowel disease may place patients at higher risk for surgery and complications after trauma.
A Phase IIa Controlled Human Malaria Infection and Immunogenicity Study of RTS,S/AS01E and RTS,S/AS01B Delayed Fractional Dose Regimens in Malaria-Naive Adults
Authors: Moon James E , Ockenhouse Christian , Regules Jason A , Vekemans Johan , Lee Cynthia , Chuang Ilin , Traskine Magali , Jongert Erik , Ivinson Karen , Morelle Danielle , Komisar Jack L , Lievens Marc , Sedegah Martha , Garver Lindsey S , Sikaffy April K , Waters Norman C , Ballou William Ripley , Ofori-Anyinam Opokua ,   RTS,S Malaria Vaccine Working Group, Cicatelli Susan B , Duncan Elizabeth H , Mills Kristin T , Lee Christine E , Epstein Judith E , Cowden Jessica J , Spring Michele D , Hamer Melinda J , Copeland Nathanial K , Ngauy Viseth , Tosh Donna M , Curley Justin M , Bennett Jason W , Riddle Mark , Waterman Paige E , Koren Michael A , Hutter Jack N , Bergmann-Leitner Elke , Kooken Jennifer , Angov Evelina , Peterson Kyle , Leprince Aurélia , Murray Linda , Cicatelli Susan B , Duncan Elizabeth H , Mills Kristin T , Lee Christine E , Epstein Judith E , Cowden Jessica J , Spring Michele D , Hamer Melinda J , Copeland Nathanial K , Ngauy Viseth , Tosh Donna M , Curley Justin M , Bennett Jason W , Riddle Mark , Waterman Paige E , Koren Michael A , Hutter Jack N , Bergmann-Leitner Elke , Kooken Jennifer , Angov Evelina , Peterson Kyle , Leprince Aurélia , Murray Linda
Published: July 2020

Background

A previous RTS,S/AS01B vaccine challenge trial demonstrated that a 3-dose (0-1-7–month) regimen with a fractional third dose can produce high vaccine efficacy (VE) in adults challenged 3 weeks after vaccination. This study explored the VE of different delayed fractional dose regimens of adult and pediatric RTS,S/AS01 formulations.

Methods

A total of 130 participants were randomized into 5 groups. Four groups received 3 doses of RTS,S/AS01B or RTS,S/AS01E on a 0-1-7–month schedule, with the final 1 or 2 doses being fractional (one-fifth dose volume). One group received 1 full (month 0) and 1 fractional (month 7) dose of RTS,S/AS01E. Immunized and unvaccinated control participants underwent Plasmodium falciparum–infected mosquito challenge (controlled human malaria infection) 3 months after immunization, a timing chosen to potentially discriminate VEs between groups.

Results

The VE of 3-dose formulations ranged from 55% (95% confidence interval, 27%–72%) to 76% (48%–89%). Groups administered equivalent formulations of RTS,S/AS01E and RTS,S/AS01B demonstrated comparable VE. The 2-dose group demonstrated lower VE (29% [95% confidence interval, 6%–46%]). All regimens were well tolerated and immunogenic, with trends toward higher anti-circumsporozoite antibody titers in participants protected against infection.

Conclusions

RTS,S/AS01E can provide VE comparable to an equivalent RTS,S/AS01B regimen in adults, suggesting a universal formulation may be considered. Results also suggest that the 2-dose regimen is inferior to the 3-dose regimens evaluated.

Clinical Trial Registration

NCT03162614
Signaling Lymphocytic Activation Molecule Family-7 Alleviates Corneal Inflammation by Promoting M2 Polarization
Authors: Zhu Siying , Chen Yu , Lao Juanfeng , Wu Chenglin , Zhan Xiaoxia , Wu Yongjian , Shang Yuqi , Zou Zhengyu , Zhou Jinyu , Ji Xiang , Huang Xi , Shi Xiaomin , Wu Minhao
Published: July 2020

Background

Signaling lymphocytic activation molecule family-7 (SLAMF7) functions as an immune checkpoint molecule on macrophages in antitumor immunity. However, its role in bacterial infection remains largely unknown.

Methods

Bone marrow-derived macrophages (BMDMs) isolated from wild-type (WT) or SLAMF7 knockout (KO) mice were infected with bacteria or treated with lipopolysaccharide/interferon-γ to investigate the expression and function of SLAMF7 in macrophage polarization. A Pseudomonas aeruginosa keratitis murine model was established to explore the effect of SLAMF7 on P. aeruginosa keratitis using WT vs SLAMF7 KO mice, or recombinant SLAMF7 vs phosphate-buffered saline-treated mice, respectively.

Results

SLAMF7 expression was enhanced on M1-polarized or bacterial-infected macrophages, and infiltrating macrophages in P. aeruginosa-infected mouse corneas. SLAMF7 promoted M2 polarization by inducing STAT6 activation. In vivo data showed that SLAMF7 KO aggravated, while treatment with recombinant SLAMF7 alleviated, corneal inflammation and disease severity. In addition, blockage of M2 polarization by Arg-1 inhibitor abrogated the effect of recombinant SLAMF7 in disease progression.

Conclusions

SLAMF7 expression in macrophages was induced upon M1 polarization or bacterial infection and alleviated corneal inflammation and disease progression of P. aeruginosa keratitis by promoting M2 polarization. These findings may provide a potential strategy for the treatment of P. aeruginosa keratitis.
Determination of Sulfamethazine in Swine and Cattle Feed by Reversed-Phase Liquid Chromatography with Post-Column Derivatization: Collaborative Study
Authors: Smallidge Robert L , Albert Kendrick ,   Collaborators:, Britton Nancy L , Campbell Harold M , Jeon Cheon-Seck , Costello Susan , Elson Kristen , Flood Kaye , Lee Jae-Ku , Lowie Dwight M , Moran John W , Mustafa Mustafa , Poe Beverly , Proksa Paul , Turner James M , Weigand Jim L , Wetzler Luann M
Published: July 2020

A liquid chromatographic (LC) method for the analysis of sulfamethazine (SMT) in complete swine and cattle feed was collaboratively studied. The method uses post-column derivatization with dimethylaminobenzaldehyde and detection at 450 nm. To 5 g finely ground feed, extractant (0.2N HCl + 1.5% diethylamine in 25% methanol), and internal standard solutions are added, and the SMT is extracted by shaking for 1 h. Clarified extract (high-level sample extract diluted to a target concentration of ca 5.5 μg/mL) is chromatographed on a C18 reversed-phase LC column with acetonitrile–2% acetic acid (17 + 83) mobile phase. Sulfamerazine is used as an internal, or surrogate standard to correct for variable recovery of sulfamethazine from a variety of feed matrixes. Six Youden matched-pair samples were sent to 10 collaborators in Korea, Canada, and the United States. Label claims on the commercial feeds ranged from 0.0077 to 0.22% SMT. The SMT mean recovery as determined from the 5 samples with known analyte content was 99.8%. The within-laboratory relative standard deviation (repeatability) ranged from 0.28 to 4.72%. Among-laboratory (including within-laboratory) relative standard deviation (reproducibility) ranged from 1.26 to 4.87%. The authors recommend the method for AOAC INTERNATIONAL Official First Action status.
Evaluation of Silica- and Sepharose-Based Immunoaffinity Sorbents for Sample Cleanup in Determination of Fumonisins B1 and B2 in Corn Products
Authors: Lawrence James F , Menard Cathie , Yeung Jupiter , Rejeb Samy Ben
Published: July 2020

Anti-fumonisin B1 polyclonal antibodies were isolated from the serum of rabbits, immobilized onto the surface of glutaraldehyde-activated silica or Sepharose CL-4B particles, and placed into empty small plastic solid-phase extraction cartridges. The immobilized antibodies were evaluated for their ability to retain fumonisin B1 and fumonisin B2. Cartridge capacity and elution conditions were determined, and the results were compared to those obtained with a commercially available cartridge. The cartridges, which were tested for their effectiveness to isolate the fumonisins from extracts of corn flour and nacho chips, detected fumonisins down to levels of about 20 ng/g. However, additional cleanup was required for detection at lower concentrations. With the use of a strong anion-exchange cartridge as a preliminary cleanup before immunoaffinity chromatography, the detection limit reached 2–5 ng/g in the products tested. The silica sorbent material exhibited strong interactions with the fumonisins, requiring acidified ethanol–water mixtures for elution and resulting in an additional degree of selectivity in isolating fumonisins from sample extracts. The silicabased immunoaffinity cartridges were successfully reused more than 10 times; the Sepharosebased cartridges were less robust. Liquid chromatography with fluorescence detection was used after prechromatographic derivatization with o-phthaldialdehyde–mercaptoethanol.
A Review of Analytical Methods for the Determination of Sulfolane and Alkanolamines in Environmental Studies
Authors: Headley John V , Fedorak Phillip M , Dickson Leslie C
Published: July 2020

Sulfolane and alkanolamines are used extensively in the processing of sour natural gases. Over many years of operation, there have been inadvertent leaks of these chemicals to groundwater and wetlands surrounding gas processing facilities, leading to uptake by vegetation. Because sulfolane and alkanolamines are extremely water-soluble, their analysis has presented challenges, particularly requirements for suitable extraction from biological matrixes and soil, along with sensitive detection using commonly available instrumentation. Analytical methods usually use gas chromatography or liquid chromatography with a variety of detector systems. Sample preparation techniques may include extraction with organic solvents, water, or a combination of these. In some cases, direct aqueous injections have been used. Derivatization of alkanolamines has been used to improve the chromatographic separations and detection. More recent procedures, using positive-ion electrospray ionization mass spectrometry (MS), have been useful for the confirmation of uptake of the alkanolamines and transformation products by wetland vegetation. Future developments will likely center on further MS analyses for identification of metabolites and transformation products in aquatic environments.
Rapid Determination of Thiamine, Riboflavin, Pyridoxine, and Niacinamide in Infant Formulas by Liquid Chromatography
Authors: Woollard David C , Indyk Harvey E
Published: July 2020

A simplified, simultaneous determination of vitamins B1, B2, B3, and B6 in supplemented infant formulas was developed from a single deproteinized sample extract, with analysis by reversed-phase, ion-pair chromatography with an acidified methanol–water mobile phase. The dioctylsulfosuccinate counter-ion facilitates unique retention of the pyridine-based vitamins (niacinamide and pyridoxine) and allows for concurrent measurement of both the pyridoxal and riboflavin 5′-phosphate endogenous components of milk. Other naturally occurring undetected vitamin congeners have minimal analytical significance. UV detection is used for niacinamide, and programmed fluorescence detection is used for riboflavin and the B6 vitamins. Thiamine is routinely determined sequentially under modified elution conditions.
Determination of Volatile Residual Solvents in Traditional Chinese Medicines by Headspace Solid-Phase Microextraction and Cryogenic Gas Chromatography with Flame Ionization Detection
Authors: Liu Jiemin , Zhou Qunfang , Jiang Guibin , Liu Jingfu , Liu Jiyan , Wen Meijuan
Published: July 2020

A method based on headspace solid-phase microextraction and cryogenic gas chromatography with flame ionization detection was developed for the determination of volatile residual solvents in traditional Chinese medicines. A laboratory-made cryogenic chromatographic system was used for the separation of 15 kinds of residual solvents. During the analysis, a 65 μm PDMS/DVB fiber was used to extract the residual solvents, the extraction time was controlled at 0°C for 15 min, and the NaCl content of the sample was maintained at 30%. The limits of detection ranged from 0.08 (for octane) to 5000 μg/L (for ethanol), and the relative standard deviations were <8%. The recoveries from spiked samples ranged from 88 to 112%. Trace levels of residual solvents in several traditional Chinese medicines were effectively identified and quantified.
Level of Endogenous Formaldehyde in Maple Syrup as Determined by Spectrofluorimetry
Authors: Lagacé Luc , Guay Stéphane , Martin Nathalie
Published: July 2020

The level of endogenous formaldehyde in maplea syrup was established from a large number (n = 300) of authentic maple syrup samples collected during 2000 and 2001 in the province of Quebec, Canada. The average level of formalde-hyde from these authentic samples was measured at 0.18 mg/kg in 2000 and 0.28 mg/kg in 2001, which is lower than previously published. These average values can be attributed to the improved spectrofluorimetric method used for the determination. However, the formaldehyde values obtained demonstrate a relatively large distribution with maximums observed at 1.04 and 1.54 mg/kg. These values are still under the maximum tolerance level of 2.0 mg/kg paraformaldehyde pesticide residue. Extensive heat treatment of maple syrup samples greatly enhanced the formaldehyde concentration of the samples, suggesting that extensive heat degradation of the sap constituents during evaporation could be responsible for the highest formal-dehyde values in maple syrup.
Determination of Seventeen Polar/Thermolabile Pesticides in Apples and Apricots by Liquid Chromatography/Mass Spectrometry
Authors: Zrostlíková Jitka , Hajšlová Jana , Kovalczuk Tomáš , Štěpán Radim , Poustka Jan
Published: July 2020

A simple liquid chromatography/mass spectrome-try (LC/MS) approach for the determination of widely used representatives of polar/thermolabile pesticides in fruits was developed and validated. The group of pesticides comprised benzimidazoles and azoles (carbendazim, thiabendazole, imazalil, propiconazole, prochloraz, epoxiconazole, flusilazole, tebuconazole, bitertanol); N-methylcarbamates (carbaryl, carbofuran, methiocarb); and phenylureas and benzoylphenylureas (linuron, diflubenzuron, triflumuron, teflubenzuron, flufenoxuron). Matrixes (apple, apricot) were extracted with acetonitrile and crude extracts were cleaned up by solid-phase ex-traction (SPE) using either mixed cation exchange or hydrophilic lipophilic balance cartridges. LC separation of pesticides was performed on a reversed-phase column, Discovery C18. Electrospray ionization and ion trap MS/MS detection were applied. For most pesticides, overall recoveries ranged from 75 to 122%, and repeatability (as relative standard deviation) from 5 repetitive determinations of recovery ranged from 3 to 21%. Carbofuran was the only compound for which recovery was not satisfactory due to its loss in the SPE cleanup step. Limits of detection were 0.1–3 μg/kg for benzimidazole and azole fungicides and carbamate insecticides. For urea insecticides, detection limits were slightly higher (3–10 μg/kg).
ISO 17025: Practical Benefits of Implementing a Quality System
Authors: Honsa Julie D , McIntyre Deborah A
Published: July 2020

As a laboratory certified to ISO 9001:2000 and accredited to ISO 17025, rtech laboratories has incorporated an overall system for technical and quality management, which results in benefits observed in daily laboratory practices. Technical requirements were updated to include the addition of formal personnel training plans and detailed records, method development and validation procedures, measurement of method uncertainty, and a defined equipment calibration and maintenance program. In addition, a stronger definition of the sample preparation process was documented to maintain consistency in sampling, and a more rigorous quality control monitoring program was implemented for chemistry and microbiology. Management quality improvements focused on document control to maintain consistent analytical processes, improved monitoring of supplier performance, a contract review process for documenting customer requirements, and a system for handling customer comments and complaints, with continuous improvement through corrective and preventive action procedures and audits. Quarterly management review of corrective actions, nonconforming testing, and proficiency testing aid in determining long-term trending. The practical benefits of these technical and management quality improvements are seen on a daily basis in the laboratory. Faster identification and resolution of issues regarding methods, personnel or equipment, improved customer satisfaction, meeting quality requirements of specialized customers, and overall increased laboratory business are all the result of implementing an effective quality system.
Indicator Organisms for Safety and Quality—Uses and Methods for Detection: Minireview
Authors: Tortorello Mary L
Published: July 2020

Indicator organisms have been used for nearly a century to assess the microbiological status of water and foods. Beginning with their use in water sanitation programs, their applications have been extended over the years to other products, and they have become important components of the microbiological testing programs of both industry and regulatory agencies. Functionally, they may be viewed as safety or quality indicators. Safety indicators suggest the presence of conditions associated with increased risk of exposure to a pathogen. Quality indicators assess conditions of importance to product manufacture or consumer acceptability. This minireview summarizes the history, use, and analytical methods for the most commonly used indicator organisms, including the aerobic plate count, yeasts and molds, the coliform groups, Escherichia coli, Enterobacteriaceae, and Listeria.
A Rapid Cleanup Method for the Isolation and Concentration of Pyrrolizidine Alkaloids in Comfrey Root
Authors: Gray Dean E , Porter Andrew , O'Neill Terry , Harris Roger K , Rottinghaus George E
Published: July 2020

Preparations from comfrey (Symphytum officinale and S. x uplandicum) root and leaf contain varying levels of the hepatotoxic pyrrolizidine alkaloids (PAs). Reference compounds for comfrey are not commercially available, and there is currently no rapid extraction or analytical method capable of determining low levels in raw materials or as adulterants in commercially available extracts. A solid-phase extraction (SPE) method was developed using an Ergosil cleanup column that specifically binds the PAs. With this method, powdered comfrey root was extracted by sonication and shaking with basic chloroform. The extract was applied to the cleanup column under vacuum, washed with 2 mL acetone–chloroform (8 + 2, v/v) followed by 2 mL petroleum ether to remove excess chloroform. The column was dried under vacuum, and the PAs were eluted with 2 successive 1 mL aliquots methanol. Percent recoveries of the PAs following Ergosil SPE had an overall average of 96.8%, with RSD of 3.8% over a range of 1.0 to 25.0 g extracted in 100 mL. Average precision of the method (n = 3 over 4 extraction concentrations) gave an overall RSD of 6.0% for the 5 alkaloids, with a range of 0.8% (5 g in 100 mL) to 11.2% (25 g in 100 mL). Recovery optimization testing showed that 1.0 g comfrey root extracted in 100 mL yielded the greatest recovery (% dry weight) of the PAs, with an extraction efficiency and accuracy of 94.2%, and RSD of 1.7% (n = 9). The unique properties of the Ergosil cleanup column provide rapid sample cleanup, volume reduction, and concentration of PAs from comfrey extracts, and allow the eluant to be analyzed directly by traditional chromatographic methods.
Rapid Identification and Quantification of Chlorpheniramine Maleate or Pheniramine Maleate in Pharmaceutical Preparations by Thin-Layer Chromatography-Densitometry
Authors: Subramaniyan Seppakkam P , Das Saroj K
Published: July 2020

Thin-layer chromatography (TLC)-densitometry was used to separate, identify, and quantitate chlorpheniramine maleate (CPM) and pheniramine maleate (PM) when present in combination with other drugs in pharmaceutical preparations of tablets, syrups, eye and ear drops, etc. CPM or PM was extracted (tablets, capsules, etc.) or diluted (liquid preparations, if needed) with 80% ethanol and isolated from other ingredients by TLC on silica gel G using cyclohexane–chloroform– methanol–diethylamine (4.5 + 4.0 + 0.5 + 1.0, v/v) as the mobile phase. Separated CPM and PM were detected under shortwave ultraviolet light and quantitated by scanning densitometry at 260 nm. Recoveries of CPM and PM were 100.09 ± 0.77% and 100.09 ± 0.87%, respectively.
Synchronous Analysis Method for Detection of Citrinin and the Lactone and Acid Forms ofMonacolin K in Red Mold Rice
Authors: Lee Chun-Lin , Wang Jyh-Jye , Pan Tzu-Ming
Published: July 2020

The Monascus product known as red mold rice (RMR) has been found to contain the cholesterol-lowering agent monacolin K (MK), including the lactone form (MKL) and the acid form (MKA) and mycotoxin citrinin (CT). In current studies, CT and MK are usually detected by different analysis methods, which have a high level of error, and are inconvenient, expensive, and time-consuming. The goal of this study is to establish a rapid synchronous analysis method for the detection of CT, MKL, and MKA levels in RMR. In this study, CT, MKL, and MKA are extracted by the same extraction method and are then separated in a reversed-phase high-performance liquid chromatography (HPLC) C18 column. The elution from the C18 column is then passed through an ultraviolet detector and introduced directly into the fluorescence detector. The results show that higher recovery rates of CT, MKL, and MLK are yielded from RMR powder by extracting with 95% ethanol (10 mL) at 60C for 30 min. Regarding the optimal conditions of HPLC, the peaks of CT, MKL, and MKA can be clearly separated from any noise peaks by isocratic elution with optimum mobile phase, acetonitrilewatertrifluoroacetate (55 + 45 + 0.05, v/v).
Studies of the Effects of Neonatal Exposure to Genistein on the Developing Female Reproductive System
Authors: Jefferson Wendy N , Padilla-Banks Elizabeth , Newbold Retha R
Published: July 2020

Studies have shown that developmental exposure to genistein alters murine reproductive differentiation, resulting in abnormal ovarian development (multioocyte follicles) and uterine neoplasia later in life. Further, reproductive function was altered. Prolonged estrous cyclicity was observed following neonatal genistein treatment (0.550 mg/kg) on Days 15 with doseand age-related increase in severity. Fertility, determined at 2, 4, and 6 months, showed decreased numbers of genistein-treated females (0.5 or 5 mg/kg) delivering live pups and reduced numbers of pups. At 6 months, 60% of 0.5 mg/kg and 40% of 5 mg/kg groups delivered live pups compared to 100% of controls. At 2 months, half the mice treated with 25 mg/kg of genistein and none treated with 50 mg/kg delivered live pups, although half of the latter group showed signs of pregnancy with few small implantation sites. Ovarian function was disrupted in the low genistein-dosed mice with increased numbers of corpora lutea (CLs) compared to controls and increased ovulated oocytes following exogenous gonadotropins treatment. In contrast, mice treated with high genistein doses had decreased numbers of CLs; ovulation could be restored with exogenous gonadotropins. Thus, neonatal treatment with genistein at environmentally relevant doses caused adverse consequences on ovarian development and reproductive function.
Determination of Butylated Hydroxytoluene in Food Samples by High-Performance Liquid Chromatography with Ultraviolet Detection and Gas Chromatography/Mass Spectrometry
Authors: Sanches-Silva Ana , Cruz José M , Sendón-Garcĺa Raquel , Paseiro-Losada Perfecto
Published: July 2020

A reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and compared with a gas chromatography/mass spectrometry (GC/MS) method for determining butylated hydroxytoluene (BHT) in foodstuffs as a result of migration from plastic packaging. Similar extraction procedures were used in both methods. BHT was quantitated using an external standard in the HPLC method and an internal standard in the GC/MS method. Both methods presented good linearity (r2 ≥ 0.9917) and low detection limits. Recoveries obtained with the HPLC method (chicken meat, 95.8%, and Gouda cheese, 83.9%) were better than with the GC/MS method (chicken meat, 85.6%, and Gouda cheese, 71.3%).
A Simple Diffuse Reflectance Fourier Transform Infrared Spectroscopic Determination of Sulfur Dioxide in Ambient Air Using Potassium Tetrachloromercurate as the Absorbing Reagent
Authors: Verma Santosh Kumar , Deb Manas Kanti , Bajpai Samir , Suzuki Yukio , Sinha Shekhar Kumar , Gong Yuan
Published: July 2020

This paper presents development of a simple, rapid, and precise analytical method for determination of sulfur dioxide in ambient air by a gas to solid-phase conversion method. Sulfur dioxide is determined in the form of sulfite (SO32) because the absorbing reagent, potassium tetrachloromercurate (TCM), used in this method absorbs sulfur dioxide from the atmosphere in the form of sulfite. Determination of submicrogram levels of sulfur dioxide was based on the selection of a quantitative analytical peak at 495 cm1 among the 3 observed vibrational peaks for the dichlorosulfitomercurate complex formed after reaction of sulfur dioxide with TCM and measurement of absorbance using diffuse reflectance Fourier transform infrared spectroscopy. The limits of detection and quantification of the method were found to be 0.09 and 0.4 g/g SO32, respectively. The precision in terms of standard deviation and relative standard deviation (RSD) at a level of 2 g SO32/0.1 g KBr for n = 10 was found to be 0.036 g SO32 and 1.8%, respectively. The RSD (n = 10) for determination of sulfur dioxide in ambient air was observed to be in the range of 2.74.2%. The method proposed is time saving and eliminates the slow and cumbersome steps of pH maintenance of the reaction mixture and color formation of the U.S. Environmental Protection Agency recommended West and Gaeke spectrophotometric method and other methods for quantitative determination of sulfur dioxide.
Development of Agribiotechnology and Biosafety Regulations Used to Assess Safety of Genetically Modified Crops in Bangladesh
Authors: Nasiruddin Khondoker Md , Nasim Anwar
Published: July 2020

Bangladesh is on the verge of adopting genetically modified (GM) crops for commercial cultivation and consumption as feed and food. Most of the laboratories are engaged in tissue culture and molecular characterization on plants, whereas some have started living modified organism research with shortages of trained manpower, infrastructure, and funding. Nutritionally improved Golden Rice, biotech brinjal, and late blight-resistant potato are in contained trials in a greenhouse, and potato ring spot virus-resistant papaya is in the process of approval for a field trial. The government has taken some initiative in support of GM organism research, which include the formation of a Biotechnology Department in all institutes and the formation of the apex body, the National Task Force Committee on Biotechnology of Bangladesh under the chairpersonship of the Prime Minister. Biosafety policy guidelines and related aspects of biotechnology issues have been approved, and the laws are in the process of being promulgated. Being a party to the Cartagena Protocol, proper biosafety measures are regulated by the appropriate authority as stated. Although there are no laws made yet directly for biosafety of GM crops/foods, the relevant laws on agriculture, medicine, food, import, trade, environment, etc. may suffice and explain the situation.
Development and Statistical Validation of a Quantitative Method for the Determination of Steroid Hormones in Environmental Water by Column Liquid Chromatography/Tandem Mass Spectrometry
Authors: Stavrakakis Christophe , Colin Ronan , Hquet Valrie , Faur Catherine , Le Cloirec Pierre
Published: July 2020

This paper presents an analytical method applied to the determination of 3 natural steroid hormones, estrone, 17 -estradiol, and 16 -hydroxyestrone, and the contraceptive estrogen, 17 -ethynylestradiol, at the sub-ng/L level in water samples [surface water and wastewater treatment plant (WWTP) samples]. The solid-phase extraction conditions were optimized using C18 cartridges. Identification and quantification were performed using a column liquid chromatographic/tandem mass spectrometric system with electrospray ionization in the negative mode. Before analyzing steroids in complex matrixes, statistical tools permitted a fine validation of the analytical method, and performance was evaluated for spring water in terms of recovery, specificity, trueness, repeatability, and intralaboratory reproducibility. The results showed the accuracy of the method, and limits of detection (LOD) ranged between 0.02 and 0.21 ng/L. The determination of steroids in WWTP effluents, which contain high levels of organic matter, required an additional purification step on silica cartridges. The high efficiency of the purification was proved with LOD <0.3 ng/L from 200 mL sample. Specificity of the entire analytical procedure was shown by repeatable recoveries at low and high levels of the calibration range.
Evaluation of the Water and Organic Liquids Extraction Efficiency of Spirulina maxima Dyes Using Thermostated Micro Thin-Layer Chromatography
Authors: Zarzycki Pawe K , Zarzycka Magdalena B
Published: July 2020

Thermostated micro thin-layer chromatography was applied for separation and quantification studies of Spirulina maxima dyes isolated from pharmaceutical formulation by a simple one-step liquid extraction. The isolation process was performed using a number of liquids, including water; 10 mM water solutions of native -, -, and -cyclodextrin and their hydroxypropyl derivatives; and a number of common organic liquids characterized by different polarity, namely, methanol, ethanol, 1-propanol, 2-propanol, acetonitrile, acetone, tetrahydrofuran, dichloromethane, toluene, and n-hexane. Chromatographic studies were performed on RP18W plates working inside a small thermostated horizontal chamber allowing a development distance of 45 mm. Using a mobile phase consisting of acetonen-hexane (30 70, v/v) and 40C separation temperature, plate peak capacity of at least 15 spots/lane and developing time <5 min were obtained. Validation data indicated that under such conditions, with an office scanner used for chromatogram digitalization, spot quantification could be accurately performed within an analyte mass range of 2 factors. The raw quantitative data obtained from microchromatograms acquired under visible light conditions were explored using cluster analysis and principal components analysis. Chemometric investigations revealed that the best extraction liquids for isolation of dye mixtures from Spirulina samples were methanol, ethanol, tetrahydrofuran, and dichloromethane. Moreover, it was found that the liquids' parachor values could be used for estimation of the dye extraction efficiency from complex samples.
Analysis of the Residues of 20 Organochlorine Pesticides in Herba epimedii, a Chinese Herbal Medicine, by Solid-Phase Extraction with Gas Chromatography/Negative Chemical Ionization–Mass Spectrometry
Authors: Guo Qing , Deng Ming , Yu Boyang , Tan Li
Published: July 2020

A multiresidue analytical method has been developed to simultaneously determine the residues of 20 organochlorine pesticides in Herba epimedii, a traditional Chinese medicine. The 20 pesticides are included in the list of regulated substances by the Food and Environmental Hygiene Department in Hong Kong. The method consists of solid-phase extraction for cleanup of samples and GC coupled on-line with negative chemical ion-MS to analyze the target pesticides. The chromatographic separation of the compounds was carried out on a DB-1701 column by using an optimal temperature program, and the quantitative analysis was conducted by selected ion monitoring. The LOD and LOQ values fell in the range of 0.05555.8821 and 0.124117.9333 ng/g, respectively. The average recoveries were between 75.4 and 90.7 (n = 5) for the 20 organochlorine pesticides. The developed method proved to be reliable and accurate, and permits rapid determination of the 20 organochlorine pesticides in one run.
Chiral Separation of Diastereoisomers of Cefuroxime Axetil by High-Performance Thin-Layer Chromatography
Authors: Dbrowska Monika , Krzek Jan
Published: July 2020

Conditions for separation and determination of diastereoisomers of cefuroxime axetil by HPTLC on cellulose layers with densitometry were developed. A good separation of the constituents was achieved using a mobile phase composed of 1 aqueous -cyclodextrinmethanol (15 + 1, v/v). For detecting spots on the chromatograms, densitometric measurements were used at 285 nm. The method is characterized by high sensitivity; the LOD was 0.04 g/spot and LOQ was 0.11 g/spot for both forms of the cefuroxime axetil diastereoisomers. For the individual diastereoisomers, high recovery values from 96.63 to 104.16 were obtained. Identification of the diastereoisomers was performed by 1H-NMR spectrometric analysis.
Mass Spectroscopic Fingerprinting Method for Differentiation Between Scutellaria lateriflora and the Germander (Teucrium canadense and T. chamaedrys) Species
Authors: Chen Pei , Lin Long-Ze , Harnly James M
Published: July 2020

Scutellaria lateriflora, commonly known as skullcap, is used as an ingredient in numerous herbal products. However, it has been occasionally adulterated/contaminated with Teucrium canadense and T. chamaedrys, commonly known as germander, which contain hepatotoxic diterpenes. Due to the morphological similarities between the two genera, analytical methodologies to distinguish authentic S. lateriflora from the Teucrium species are needed to ensure public safety. In this study, a direct-injection electrospray ionization/MS method was used to generate spectral fingerprints of extracts from 21 skullcap and germander samples at a rate of 90 s/sample. MS fingerprints were analyzed by principal component analysis. The newly developed method offers a rapid and easy way to differentiate between skullcap and germander samples.
Application of Ultra-Performance Liquid Chromatography/Tandem Mass Spectrometry for the Measurement of Vitamin D in Foods and Nutritional Supplements
Authors: Huang Min , Winters Doug
Published: July 2020

Ultra-performance liquid chromatography (UPLC)/MS/MS was applied to measure vitamin D in various foods and nutritional supplements. The run-time of the chromatographic separation was cut from 20 min in HPLC/MS/MS to 10 min in UPLC/MS/MS, while equal or better separation efficiency was achieved to deal with complex food matrixes. Under the optimized conditions, all the previtamins of vitamin D3, D2, and isotope-labeled vitamin D3 were baseline-separated from their corresponding vitamins. It was also demonstrated that many sterol isomers in complex food matrixes that interfere in the analysis could be well-separated from the analytes. Accuracy of this method was evaluated by analysis of NIST SRM 1849 infant formula reference material. With eight replicates, the average vitamin D3 concentration was 0.251 + 0.012 mg/kg, an excellent agreement with the certified value of 0.251 + 0.027 mg/kg. In addition, spike recovery from a commercial infant formula matrix was in the range of 100 to 108% for both vitamins D3 and D2 at three spike concentration levels. The spike recovery for an even more complex matrix, pet food, was 101–105%. LOQ values were 0.026 and 0.033 IU/g, or 0.086 and 0.11 IU/mL in solution, for vitamins D3 and D2, respectively. The dynamic range had three orders of magnitude, which made the method flexible and useful to deal with the wide concentration range of vitamin D in various samples. The method was robust based on the results of changing the parameters of LC separation and MS measurement. This accurate and reliable vitamin D method increased instrument efficiency and analysis productivity significantly.