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1.
Proc Natl Acad Sci U S A ; 120(34): e2300585120, 2023 08 22.
Article in English | MEDLINE | ID: mdl-37590414

ABSTRACT

Interneuron populations within the nucleus accumbens (NAc) orchestrate excitatory-inhibitory balance, undergo experience-dependent plasticity, and gate-motivated behavior, all biobehavioral processes heavily modulated by endogenous cannabinoid (eCB) signaling. While eCBs are well known to regulate synaptic plasticity onto NAc medium spiny neurons and modulate NAc function at the behavioral level, how eCBs regulate NAc interneuron function is less well understood. Here, we show that eCB signaling differentially regulates glutamatergic and feedforward GABAergic transmission onto NAc somatostatin-expressing interneurons (NAcSOM+) in an input-specific manner, while simultaneously increasing postsynaptic excitability of NAcSOM+ neurons, ultimately biasing toward vHPC (ventral hippocampal), and away from BLA (basolateral amygdalalar), activation of NAcSOM+ neurons. We further demonstrate that NAcSOM+ are activated by stress in vivo and undergo stress-dependent plasticity, evident as a global increase in intrinsic excitability and an increase in excitation-inhibition balance specifically at vHPC, but not BLA, inputs onto NAcSOM+ neurons. Importantly, both forms of stress-induced plasticity are dependent on eCB signaling at cannabinoid type 1 receptors. These findings reveal eCB-dependent mechanisms that sculpt afferent input and excitability of NAcSOM+ neurons and demonstrate a key role for eCB signaling in stress-induced plasticity of NAcSOM+-associated circuits.


Subject(s)
Cannabinoids , Endocannabinoids , Nucleus Accumbens , Neurons , Somatostatin
2.
RNA ; 29(5): 557-569, 2023 05.
Article in English | MEDLINE | ID: mdl-36737102

ABSTRACT

PIWI-interacting RNAs (piRNAs) protect genome integrity by silencing transposon mRNAs and some endogenous mRNAs in various animals. However, C. elegans piRNAs only trigger gene silencing at select predicted targeting sites, suggesting additional cellular mechanisms regulate piRNA silencing. To gain insight into possible mechanisms, we compared the transcriptome-wide predicted piRNA targeting sites to the in vivo piRNA binding sites. Surprisingly, while sequence-based predicted piRNA targeting sites are enriched in 3' UTRs, we found that C. elegans piRNAs preferentially bind to coding regions (CDS) of target mRNAs, leading to preferential production of secondary silencing small RNAs in the CDS. However, our analyses suggest that this CDS binding preference cannot be explained by the action of antisilencing Argonaute CSR-1. Instead, our analyses imply that CSR-1 protects mRNAs from piRNA silencing through two distinct mechanisms-by inhibiting piRNA binding across the entire CSR-1 targeted transcript, and by inhibiting secondary silencing small RNA production locally at CSR-1 bound sites. Together, our work identifies the CDS as the critical region that is uniquely competent for piRNA binding in C. elegans. We speculate the CDS binding preference may have evolved to allow the piRNA pathway to maintain robust recognition of RNA targets in spite of genetic drift. Together, our analyses revealed that distinct mechanisms are responsible for restricting piRNA binding and silencing to achieve proper transcriptome surveillance.


Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans , Animals , Caenorhabditis elegans/genetics , Caenorhabditis elegans/metabolism , Piwi-Interacting RNA , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Transcriptome , Argonaute Proteins/genetics , Argonaute Proteins/metabolism , RNA, Double-Stranded/metabolism , Binding Sites , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism
3.
Article in English | MEDLINE | ID: mdl-38981605

ABSTRACT

Glutamine is a critical amino acid that serves as an energy source, building block, and signaling molecule for the heart tissue and the immune system. However, the role of glutamine metabolism in regulating cardiac remodeling following myocardial infarction (MI) is unknown. In this study, we show in adult male mice that glutamine metabolism is altered both in the remote (contractile) area and in infiltrating macrophages in the infarct area after permanent left anterior descending artery occlusion. We found that metabolites related to glutamine metabolism were differentially altered in macrophages at days 1, 3, and 7 after MI using untargeted metabolomics. Glutamine metabolism in live cells was increased after MI relative to no MI controls. Gene expression in the remote area of the heart indicated a loss of glutamine metabolism. Glutamine administration improved LV function at days 1, 3, and 7 after MI, which was associated with improved contractile and metabolic gene expression. Conversely, administration of BPTES, a pharmacological inhibitor of glutaminase-1, worsened LV function after MI. Neither glutamine nor BPTES administration impacted gene expression or bioenergetics of macrophages isolated from the infarct area. Our results indicate that glutamine metabolism plays a critical role in maintaining LV contractile function following MI, and that glutamine administration improves LV function. Glutamine metabolism may also play a role in regulating macrophage function, but macrophages are not responsive to exogenous pharmacological manipulation of glutamine metabolism.

4.
Genet Med ; 24(1): 87-99, 2022 01.
Article in English | MEDLINE | ID: mdl-34906463

ABSTRACT

PURPOSE: The growing size of public variant repositories prompted us to test the accuracy of pathogenicity prediction of DNA variants using population data alone. METHODS: Under the a priori assumption that the ratio of the prevalence of variants in healthy population vs that in affected populations form 2 distinct distributions (pathogenic and benign), we used a Bayesian method to assign probability to a variant belonging to either distribution. RESULTS: The approach, termed Bayesian prevalence ratio (BayPR), accurately parsed 300 of 313 expertly curated CFTR variants: 284 of 296 pathogenic/likely pathogenic variants in 1 distribution and 16 of 17 benign/likely benign variants in another. BayPR produced an area under the receiver operating characteristic curve of 0.99 for 103 functionally confirmed missense CFTR variants, which is equal to or exceeds 10 commonly used algorithms (area under the receiver operating characteristic curve range = 0.54-0.99). Application of BayPR to expertly curated variants in 8 genes associated with 7 Mendelian conditions led to the assignment of a disease-causing probability of ≥80% to 1350 of 1374 (98.3%) pathogenic/likely pathogenic variants and of ≤20% to 22 of 23 (95.7%) benign/likely benign variants. CONCLUSION: Irrespective of the variant type or functional effect, the BayPR approach provides probabilities of pathogenicity for DNA variants responsible for Mendelian disorders using only the variant counts in affected and unaffected population samples.


Subject(s)
Algorithms , Mutation, Missense , Bayes Theorem , Humans , ROC Curve
5.
Mult Scler ; 27(6): 807-811, 2021 05.
Article in English | MEDLINE | ID: mdl-32507072

ABSTRACT

Intestinal microbiota alterations have been found to be directly related to a wide range of disease states in humans, including multiple sclerosis (MS). The etiology of MS is highly debated and subsequently, there is no cure. Research dedicated to MS and its murine model, experimental autoimmune encephalomyelitis (EAE), have found that dysbiosis of the gut microbiota may play a role in the disease state and severity. In this review, we discuss the characteristic dysbiosis in MS, the role commensal-derived ligands may have in the pathogenesis of the disease, and the possibility of targeting the microbiota as a future therapy.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Gastrointestinal Microbiome , Multiple Sclerosis , Animals , Dysbiosis , Humans , Immunity , Mice
6.
J Phycol ; 57(6): 1768-1776, 2021 12.
Article in English | MEDLINE | ID: mdl-34490918

ABSTRACT

Cyanotoxins are an emerging threat to freshwater resources worldwide. The most frequently reported cyanotoxins are the microcystins, which threaten the health of humans, wildlife, and ecosystems. Determining the potential for microcystin production is hindered by a lack of morphological features that correlate with microcystin production. However, amplicon-based methods permit the detection of microcystin biosynthesis genes and were employed to assess the toxin potential in Lake Utopia, NB, Canada, an oligotrophic lake that occasionally experiences cyanobacteria blooms. Samples collected at 2 week intervals from June 27th to September 27th, 2016, were screened by polymerase chain reaction (PCR) for the microcystin synthetase E gene (mcyE). The mcyE gene was present in some samples every sampling day, despite microcystin not being detected via ELISA, and was most frequently associated with the larger pore size fractions of the serially filtered samples. Further PCR surveys using primer sets to amplify genus-specific (e.g., Microcystis, Anabaena/Dolichospermum, and Planktothrix) mcyE fragments identified Microcystis as the only taxa in Lake Utopia with toxigenic potential. Sequencing of the 16S rRNA V3-V4 region revealed a community dominated by members of the order Synechococcales (from 38 to 96% relative abundance), but with significant presence of taxa from Cyanobacteriales including Microcystaceae and Nostocaceae. A persistent Microcystis population was detected in samples both testing positive and negative for the mcyE gene, highlighting the importance of identifying cyanotoxin production potential by gene presence and not species identity. To our knowledge, this study represents the first application of amplicon-based approaches to studying toxic cyanobacteria in an understudied region-Atlantic Canada.


Subject(s)
Cyanobacteria , Microcystis , Cyanobacteria/genetics , Cyanobacteria Toxins , Ecosystem , Lakes , Microcystins , RNA, Ribosomal, 16S/genetics
7.
Nucleic Acids Res ; 47(D1): D181-D187, 2019 01 08.
Article in English | MEDLINE | ID: mdl-30357353

ABSTRACT

PIWI-interacting RNAs (piRNAs) are a class of small noncoding RNAs that guard animal genomes against mutation by silencing transposons. In addition, recent studies have reported that piRNAs silence various endogenous genes. Tens of thousands of distinct piRNAs made in animals do not pair well to transposons and currently the functions and targets of piRNAs are largely unexplored. piRTarBase provides a user-friendly interface to access both predicted and experimentally identified piRNA targeting sites in Caenorhabditis elegans. The user can input genes of interest and retrieve a list of piRNA targeting sites on the input genes. Alternatively, the user can input a piRNA and retrieve a list of its mRNA targets. Additionally, piRTarBase integrates published mRNA and small RNA sequencing data, which will help users identify biologically relevant targeting events. Importantly, our analyses suggest that the piRNA sites found by both predictive and experimental approaches are more likely to exhibit silencing effects on their targets than each method alone. Taken together, piRTarBase offers an integrative platform that will help users to identify functional piRNA target sites by evaluating various information. piRTarBase is freely available for academic use at http://cosbi6.ee.ncku.edu.tw/piRTarBase/.


Subject(s)
Binding Sites , Databases, Genetic , Gene Expression Regulation , Gene Silencing , RNA Interference , RNA, Messenger/genetics , RNA, Small Interfering/genetics , Software , Web Browser , Workflow
8.
Nucleic Acids Res ; 46(W1): W43-W48, 2018 07 02.
Article in English | MEDLINE | ID: mdl-29897582

ABSTRACT

pirScan is a web-based tool for identifying C. elegans piRNA-targeting sites within a given mRNA or spliced DNA sequence. The purpose of our tool is to allow C. elegans researchers to predict piRNA targeting sites and to avoid the persistent germline silencing of transgenes that has rendered many constructs unusable. pirScan fulfills this purpose by first enumerating the predicted piRNA-targeting sites present in an input sequence. This prediction can be exported in a tabular or graphical format. Subsequently, pirScan suggests silent mutations that can be introduced to the input sequence that would allow the modified transgene to avoid piRNA targeting. The user can customize the piRNA targeting stringency and the silent mutations that he/she wants to introduce into the sequence. The modified sequences can be re-submitted to be certain that any previously present piRNA-targeting sites are now absent and no new piRNA-targeting sites are accidentally generated. This revised sequence can finally be downloaded as a text file and/or visualized in a graphical format. pirScan is freely available for academic use at http://cosbi4.ee.ncku.edu.tw/pirScan/.


Subject(s)
Caenorhabditis elegans/genetics , Internet , RNA, Small Interfering/genetics , Software , Animals , Computational Biology/trends , RNA, Small Interfering/chemistry
9.
Prenat Diagn ; 39(6): 448-455, 2019 05.
Article in English | MEDLINE | ID: mdl-30883831

ABSTRACT

The prenatal genetic counseling process may be influenced by the patient's insurance coverage for both prenatal testing and termination. Major commercial insurance providers have different policies. TRICARE is the United States Department of Defense health program for uniformed service members. TRICARE provides coverage to approximately 9.4 million beneficiaries, including health plans, special programs, prescriptions, and dental plans. TRICARE's covered medical expenses are outlined in their policies, including those pertaining to genetic testing and termination. This qualitative study aimed to explore the extent to which insurance coverage of prenatal genetic testing and termination of pregnancy affect the genetic counseling process by exploring genetic counselors' experience with TRICARE. The majority of counselors stated that they did not change their overall counseling process for TRICARE patients. However, several counselors expressed that they changed the way they discussed cost with TRICARE patients, specifically in regard to genetic testing. Additionally, counselors provided their perceptions of their patients' emotional experiences. With the recent consolidation of the three TRICARE regions into two TRICARE Regional Office (TRO) regions and the renewal of the Laboratory Developed Tests Demonstration Project, the findings of this study are valuable in the evaluation of TRICARE's coverage of prenatal genetic services.


Subject(s)
Counselors , Genetic Counseling/supply & distribution , Insurance Coverage , Military Health/economics , Prenatal Diagnosis , Professional Practice , Abortion, Eugenic/economics , Abortion, Eugenic/statistics & numerical data , Counselors/psychology , Counselors/statistics & numerical data , Counselors/supply & distribution , Female , Frustration , Genetic Counseling/economics , Genetic Counseling/statistics & numerical data , Genetic Testing/economics , Genetic Testing/statistics & numerical data , Health Services Accessibility/economics , Health Services Accessibility/statistics & numerical data , Humans , Insurance Coverage/economics , Insurance Coverage/statistics & numerical data , Interviews as Topic , Military Health/statistics & numerical data , Military Personnel/statistics & numerical data , Pregnancy , Prenatal Diagnosis/economics , Prenatal Diagnosis/statistics & numerical data , Professional Practice/standards , Professional Practice/statistics & numerical data , Referral and Consultation/economics , Referral and Consultation/statistics & numerical data , Surveys and Questionnaires , United States/epidemiology , United States Department of Defense/economics
12.
Trop Anim Health Prod ; 49(6): 1117-1124, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28523387

ABSTRACT

The objective of this study was to evaluate the seroprevalence and identify the strains of swine influenza virus (SwIV), as well as the seroprevalence of porcine parvovirus (PPV), transmissible gastroenteritis virus (TGEV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine respiratory coronavirus (PRCV), porcine circovirus type 2 (PCV-2), and classical swine fever virus (CSFV) in pigs in Trinidad and Tobago (T&T). Blood samples (309) were randomly collected from pigs at farms throughout T&T. Serum samples were tested for the presence of antibodies to the aforementioned viruses using commercial ELISA kits, and the circulating strains of SwIV were identified by the hemagglutination inhibition test (HIT). Antibodies against SwIV were detected in 114 out of the 309 samples (37%). Out of a total of 26 farms, 14 tested positive for SwIV antibodies. HI testing revealed high titers against the A/sw/Minnesota/593/99 H3N2 strain and the pH1N1 2009 pandemic strain. Antibodies against PPV were detected in 87 out of the 309 samples (28%), with 11 out of 26 farms testing positive for PPV antibodies. Antibodies against PCV-2 were detected in 205 out of the 309 samples tested (66%), with 25 out of the 26 farms testing positive for PCV-2 antibodies. No antibodies were detected in any of the tested pigs to PRRSV, TGEV, PRCV, or CSFV.


Subject(s)
Orthomyxoviridae/isolation & purification , Swine Diseases/epidemiology , Virus Diseases/veterinary , Animals , Orthomyxoviridae Infections/epidemiology , Orthomyxoviridae Infections/veterinary , Orthomyxoviridae Infections/virology , Prevalence , Seroepidemiologic Studies , Swine , Swine Diseases/virology , Trinidad and Tobago/epidemiology , Virus Diseases/epidemiology , Virus Diseases/virology
13.
Radiographics ; 36(2): 452-63, 2016.
Article in English | MEDLINE | ID: mdl-26963456

ABSTRACT

Ultrasonography (US) has become a first-line modality for the evaluation of the peripheral nerves of the upper extremity. The benefits of US over magnetic resonance (MR) imaging include higher soft-tissue resolution, cost effectiveness, portability, real-time and dynamic imaging, and the ability to scan an entire extremity quickly and efficiently. US can be performed on patients who are not eligible for MR imaging. Metallic implant artifacts are usually not problematic. US has been shown to have equal specificity and greater sensitivity than MR imaging in the evaluation of peripheral nerves. Any abnormal findings can be easily compared with the contralateral side. The published literature has shown that US has demonstrated clinical utility in patients with suspected peripheral nerve disease by guiding diagnostic and therapeutic decisions as well as by confirming electrodiagnostic findings. Common indications for upper extremity peripheral nerve US are the evaluation for injury due to penetrating trauma, entrapment by scar tissue, and tumor. US of the upper extremity is most commonly performed to evaluate carpal and cubital tunnel syndrome. It is important for the radiologist or sonographer to have a detailed knowledge of anatomy and specific anatomic landmarks for each nerve to efficiently and accurately perform an examination. The goal of this article is to introduce readers to the basics of US of the peripheral nerves of the upper extremity with a focus on the median, ulnar, and radial nerves. Common sites of disease and the location of important anatomic landmarks will be reviewed.


Subject(s)
Arm/innervation , Peripheral Nerves/diagnostic imaging , Peripheral Nervous System Diseases/diagnostic imaging , Ultrasonography/methods , Arm/diagnostic imaging , Humans , Magnetic Resonance Imaging , Median Nerve/diagnostic imaging , Peripheral Nerve Injuries/diagnostic imaging , Radial Nerve/diagnostic imaging , Ulnar Nerve/diagnostic imaging , Ultrasonography/instrumentation
14.
Anal Chem ; 87(7): 3623-30, 2015 Apr 07.
Article in English | MEDLINE | ID: mdl-25741857

ABSTRACT

Throughout the fields of biomedical imaging, materials analysis, and routine chemical analysis, it is desirable to have a toolkit of molecules that can allow noninvasive/remote chemical sensing with minimal sample preparation. Here, we describe the photophysical properties involved in photoacoustic (PA) measurements and present a detailed analysis of the requirements and complications involved in PA sensing. We report the use of nitrazine yellow (NY) as a well-behaved PA pH reporter molecule. Both the basic and acidic forms of NY are photoacoustically well-behaved and allow for rapid and noninvasive measurement of pH in either transparent or turbid media. We also find that the serum protein-bound form of NY is photoacoustically well-behaved and should permit applications in noninvasive 3D imaging (e.g., the lymphatic system).

15.
Am J Med Genet A ; 167A(12): 3180-5, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26338144

ABSTRACT

Intellectual disability (ID) is estimated to affect 1-3% of the general population and is a common reason for referrals to pediatric and adult geneticists, as well as neurologists. There are many genetic and non-genetic causes of ID; X-linked forms are identifiable through their characteristic inheritance pattern. Current testing methods have been able to identify over 100 genes on the X chromosome responsible for X-linked intellectual disability (XLID) syndromes. MED12 [MIM *300188] (mediator complex subunit 12) mutations have been linked to numerous XLID syndromes, including Lujan, FG, and Ohdo, and MED12 is included in many XLID panels. MED12 is located at Xq13.1 and its product has roles in transcriptional activation and repression. We describe two affected male siblings and their unaffected mother with a novel missense mutation in MED12, c.4147G>A (p.Ala1383Thr). The siblings share some features of Ohdo syndrome, including feeding difficulties, microcephaly, and speech delay. However, additional attributes such as hypertonia, eosinophilic esophagitis, penile chordee, and particular facial dysmorphisms depart sufficiently from individuals previously described such that they appear to represent a new and expanded phenotype. This case lends credence to the evolving theory that the subtypes of Ohdo, and perhaps other MED12 disorders, reflect a spectrum of characteristics, rather than distinct syndromes. As XLID panel testing and whole exome sequencing (WES) becomes a standard of care for affected males, further MED12 mutations will broaden the phenotype of these intriguing disorders and challenge clinicians to rethink the current diagnostic boundaries.


Subject(s)
Abnormalities, Multiple/genetics , Blepharophimosis/genetics , Blepharoptosis/genetics , Craniofacial Abnormalities/genetics , Eosinophilic Esophagitis/genetics , Genes, X-Linked/genetics , Heart Defects, Congenital/genetics , Intellectual Disability/genetics , Mediator Complex/genetics , Muscle Hypertonia/genetics , Muscular Atrophy/genetics , Mutation, Missense/genetics , Abnormalities, Multiple/pathology , Adult , Blepharophimosis/pathology , Blepharoptosis/pathology , Child , Craniofacial Abnormalities/pathology , Eosinophilic Esophagitis/pathology , Heart Defects, Congenital/pathology , Humans , Infant , Intellectual Disability/pathology , Male , Muscle Hypertonia/pathology , Muscular Atrophy/pathology , Phenotype , Prognosis
16.
Scand J Gastroenterol ; 50(9): 1076-87, 2015.
Article in English | MEDLINE | ID: mdl-25865706

ABSTRACT

OBJECTIVE: Breath testing and duodenal culture studies suggest that a significant proportion of irritable bowel syndrome (IBS) patients have small intestinal bacterial overgrowth. In this study, we extended these data through 16S rDNA amplicon sequencing and quantitative PCR (qPCR) analyses of duodenal aspirates from a large cohort of IBS, non-IBS and control subjects. MATERIALS AND METHODS: Consecutive subjects presenting for esophagogastroduodenoscopy only and healthy controls were recruited. Exclusion criteria included recent antibiotic or probiotic use. Following extensive medical work-up, patients were evaluated for symptoms of IBS. DNAs were isolated from duodenal aspirates obtained during endoscopy. Microbial populations in a subset of IBS subjects and controls were compared by 16S profiling. Duodenal microbes were then quantitated in the entire cohort by qPCR and the results compared with quantitative live culture data. RESULTS: A total of 258 subjects were recruited (21 healthy, 163 non-healthy non-IBS, and 74 IBS). 16S profiling in five IBS and five control subjects revealed significantly lower microbial diversity in the duodenum in IBS, with significant alterations in 12 genera (false discovery rate < 0.15), including overrepresentation of Escherichia/Shigella (p = 0.005) and Aeromonas (p = 0.051) and underrepresentation of Acinetobacter (p = 0.024), Citrobacter (p = 0.031) and Microvirgula (p = 0.036). qPCR in all 258 subjects confirmed greater levels of Escherichia coli in IBS and also revealed increases in Klebsiella spp, which correlated strongly with quantitative culture data. CONCLUSIONS: 16S rDNA sequencing confirms microbial overgrowth in the small bowel in IBS, with a concomitant reduction in diversity. qPCR supports alterations in specific microbial populations in IBS.


Subject(s)
DNA, Bacterial/analysis , DNA, Bacterial/isolation & purification , Duodenum/microbiology , Feces/microbiology , Gastrointestinal Microbiome/genetics , Irritable Bowel Syndrome/microbiology , Adult , Aged , Aged, 80 and over , Case-Control Studies , Endoscopy, Gastrointestinal , Female , Humans , Male , Middle Aged , Prospective Studies , Real-Time Polymerase Chain Reaction
17.
J Relig Health ; 53(5): 1317-28, 2014 Oct.
Article in English | MEDLINE | ID: mdl-23625127

ABSTRACT

For people living with HIV (PLWH), spirituality and optimism have a positive influence on their health, can slow HIV disease progression, and can improve quality of life. Our aim was to describe longitudinal changes in spirituality and optimism after participation in the SystemCHANGE™-HIV intervention. Upon completion of the intervention, participants experienced an 11.5 point increase in overall spiritual well-being (p = 0.036), a 6.3 point increase in religious well-being (p = 0.030), a 4.8 point increase in existential well-being (p = 0.125), and a 0.8 point increase in total optimism (p = 0.268) relative to controls. Our data suggest a group-based self-management intervention increases spiritual well-being in PLWH.


Subject(s)
Attitude to Health , HIV Infections/psychology , HIV Infections/therapy , Holistic Health , Self Care/methods , Spirituality , Adaptation, Psychological , Female , Humans , Longitudinal Studies , Male , Middle Aged , Personal Satisfaction , Quality of Life/psychology
18.
J Anal Toxicol ; 48(2): 111-118, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38287693

ABSTRACT

A safe and productive workplace requires a sober workforce, free from substances that impair judgment and concentration. Although drug monitoring programs already exist, the scope and loopholes of standard workplace testing panels are well known, allowing other substances to remain a source of risk. Therefore, a high-throughput urine screening method for psilocin, mitragynine, phencyclidine, ketamine, norketamine and dehydronorketamine was developed and validated in conjunction with a urine and blood confirmation method. There are analytical challenges to overcome with psilocin and mitragynine, particularly when it comes to drug stability and unambiguous identification in authentic specimens. Screening and confirmation methods were validated according to the American National Standards Institute/Academy Standards Board (ANSI/ASB) Standard 036, Standard Practices for Method Validation in Forensic Toxicology. An automated liquid handling system equipped with dispersive pipette extraction tips was utilized for preparing screening samples, whereas an offline solid-phase extraction method was used for confirmation sample preparation. Both methods utilized liquid chromatography-tandem mass spectrometry to achieve limits of detection between 1-5 ng/mL for the screening method and 1 ng/mL for the confirmation method. Automation allows for faster throughput and enhanced quality assurance, which improves turnaround time. Compared to previous in-house methods, specimen volumes were substantially decreased for both blood and urine, which is an advantage when volume is limited. This screening technique is well suited for evaluating large numbers of specimens from those employed in safety-sensitive workforce positions. This method can be utilized by workplace drug testing, human performance and postmortem laboratories seeking robust qualitative screening and confirmation methods for analytes that have traditionally been challenging to routinely analyze.


Subject(s)
Ketamine , Psilocybin/analogs & derivatives , Secologanin Tryptamine Alkaloids , Humans , Phencyclidine , Tandem Mass Spectrometry/methods , Chromatography, Liquid/methods
19.
J Anal Toxicol ; 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38648393

ABSTRACT

With a wider availability of synthetic and semi-synthetic cannabinoids in the consumer space, there is a growing impact on public health and safety. Forensic toxicology laboratories should keep these compounds in mind as they attempt to remain effective in screening for potential sources of human performance impairment. Enzyme-linked immunosorbent assay (ELISA) is a commonly utilized tool in forensic toxicology, as its efficiency and sensitivity make it useful for rapid and easy screening for a large number of drugs. This screening technique has lower specificity, which allows for broad cross-reactivity among structurally-similar compounds. In this study, the Cannabinoids Direct ELISA kit from Immunalysis was utilized to assess the cross-reactivities of 24 cannabinoids and metabolites in whole blood. The assay was calibrated with 5 ng/mL of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol and the analytes of interest were evaluated at concentrations ranging from 5 to 500 ng/mL. Most parent compounds demonstrated cross-reactivity ≥ 20 ng/mL, with increasing alkyl side chain length relative to Δ9-tetrahydrocannabinol resulting in decreased cross-reactivity. Of the 24 analytes, only the carboxylic acid metabolites, 11-nor-9-carboxy-Δ8-tetrahydrocannabinol, 11-nor-9(R)-carboxy-hexahydrocannabinol, and 11-nor-9(S)-carboxy-hexahydrocannabinol, were cross-reactive at levels ≤ 10 ng/mL. Interestingly, 11-nor-9(R)-carboxy-hexahydrocannabinol demonstrated cross-reactivity at 5 ng/mL, where its stereoisomer 11-nor-9(S)-carboxy-hexahydrocannabinol, did not. As more information emerges about the prevalence of these analytes in blood specimens, it is important to understand and characterize their impact on current testing paradigms.

20.
Microbiol Resour Announc ; 13(3): e0099923, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38299841

ABSTRACT

Here, we announce the complete genome of a previously undescribed papillomavirus from a betta fish, Betta splendens. The genome is 5,671 bp with a GC content of 38.2%. Variants were detected in public databases. This genome is most similar to papillomaviruses that infect sea bass (52.9 % nucleotide identity).

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