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BACKGROUND: Toronto's Drug Checking Service (DCS) provides people who use drugs with information on the chemical composition of their substances and conducts real-time monitoring of the unregulated drug supply. Presented are first known data of three newly detected synthetic cannabinoids (SCs) in Toronto, Ontario. METHODS: The present data are from samples analyzed between April and November 2020. Samples were collected at partnering harm reduction agencies in Toronto and analyzed using gas or liquid chromatography-mass spectrometry. An intake survey queried about the sample characteristics on submission, including expected drug(s). RESULTS: Samples were analyzed between 1 April and 20 November 2020 (N = 19), which marks the period immediately following imposed COVID-19 border and movement restrictions in Canada. The newly detected, unexpected SCs were ACHMINACA (n = 15), AB-FUBINACA (n = 3), and 4-fluoro-MDMB-BUTINACA (n = 1). Fentanyl was expected in 74% (n = 14). Most SCs were detected in samples containing fentanyl or related analogues (n = 18; 95%), or benzodiazepine-related drugs (i.e., etizolam and flualprazolam) (n = 15; 79%). CONCLUSIONS: This information can inform overdose prevention efforts and drug market monitoring of SCs in Toronto and regions served by the same drug trafficking routes. The detection of SCs during a period marked by COVID-19-related restrictions can contribute to efforts to identify global drug market trends during this time.

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BACKGROUND: In response to the opioid crisis, over the last 10 years substantial strides have been made to increase the availability of evidence-based treatments for opioid use disorder, in particular buprenorphine maintenance, in the United States. Despite these worthwhile efforts, uptake rates of evidence-based treatment remain relatively low. As part of a broader study of opioid misuse, we examined proximity to evidence-based treatment as a potential barrier to treatment access. METHODS: In 2017-2018, we surveyed 218 individuals misusing prescription opioids or using street opioids in three Southern Californian counties. The study calculated driving distance from place of residence to the closest treatment provider offering buprenorphine or methadone treatment for opioid use disorders. RESULTS: Median distance to providers was 3.8 km (2.4 miles). Seventy one (33%) participants had received some form of treatment in the last 3 months; however, only 26 (40%) of these had received buprenorphine or methadone maintenance treatment. Participants receiving treatment at the time of their interview were traveling an average 16.8 km (10.4 miles) to reach treatment, indicating that as a group this population was both willing and able to seek and engage with treatment. CONCLUSIONS: In the suburban and exurban communities in which our study was based, our findings suggest that simple physical proximity to providers of evidence-based treatment for opioid use disorder is no longer a critical barrier. Other barriers to uptake of buprenorphine or methadone maintenance treatment clearly remain and need to be addressed. DISCLAIMER: Findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

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BACKGROUND: 12-step programs aim to address drug-related harms, like opioid overdose, via abstinence. However, abstaining from opioids can diminish tolerance, which increases risk for overdose death upon resumption. A recent study found that desire to abstain from drugs inhibited willingness to participate in take-home naloxone programming, which was linked to perceptions of harm reduction strategies being tied to drug use. In the present study, we uncovered a similar phenomenon occurring among newly-abstinent participants who were refusing to carry naloxone. METHODS: This study is an analysis of broader qualitative data collected throughout Southern California among persons who use opioids, including those recently abstinent. Preliminary analysis revealed that those newly abstinent refused to accept naloxone at the end of interviews, and so we began probing about this (N=44). We used thematic analysis and author positionality to explicate the emergent phenomenon and applied social identity theory to conceptualize findings. RESULTS: Mechanisms underlying naloxone refusal included its tie to a drug-using identity that newly-abstinent participants were attempting to retire. Carrying naloxone was also viewed as pointless due to doubt of witnessing an overdose again. Furthermore, the thought of being equipped with naloxone was not believed to be congruent with an abstinent identity, e.g. "me carrying it [naloxone] is making me feel like I'm going to be hanging out with people that are doing it [using drugs]." CONCLUSION: Recent detoxification heightens vulnerability to overdose, which other newly-abstinent peers might be positioned to respond to as bonds are formed through 12-step identity formation. However, naloxone is often refused by this group due to perceived 12-step identity clash. While some treatment spaces distribute naloxone, 12-step identity associated behavioral expectations appear to conflict with this strategy. Reframing these disconnects is essential for expanding the lifesaving naloxone community safety net.

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While rates of opioid overdose deaths in North American have increased exponentially in recent years, most overdoses are not fatal, especially when witnesses are present and can intervene. Previous research has found that some people who use drugs [PWUDs] trained in overdose response might cut social ties with frequent overdosers, leading to more solitary opioid use and risk of death if someone overdoses alone. To examine the phenomenon of social distancing of people who overdose frequently, we used data from fifty-two in-depth qualitative interviews collected in Southern California with PWUDs who had recently witnessed an opioid overdose. Transcripts were reviewed and coded thematically, using the Integrated Threat Theory (ITT) to conceptualize the observed phenomenon. ITT outlines how realistic and symbolic threats are experienced by a group. We found that while some participants acknowledged the role of adulterated street drugs in overdoses, individualized blame was nonetheless imposed. Accusations of careless drug use practices fostered negative stereotyping towards frequent overdosers. This was attributed to the need to summon 911 for rescue, which often resulted in police dispatch. The intergroup relationship between police and PWUDs is precarious as police pose realistic threats onto PWUDs - such as incarceration, eviction, and manslaughter charges - leading to intragroup anxiety among PWUDs about future overdose events, and labelled frequent overdosers as liabilities. These threats, and inter/intra-group conflict, explained one reason how and why non-fatal overdoses led to social distancing events. People who overdose frequently were also accused of breaking the norm of drug user surreptitiousness; a symbolic threat that endangered the group due to police exposure. Social distancing might dampen exposure to the protective effect of peer-led interventions such as take-home naloxone programs, increasing risk of overdose death. This phenomenon highlights how intergroup dynamics are driving intragroup processes. Suggestions for tailoring public health interventions are discussed.

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INTRODUCTION: Research identifying pathways to heroin use has typically been conducted among urban populations. This study examined heroin initiation following pharmaceutical opioid use in three suburban/exurban Southern California counties. METHODS: Interviewer-administered surveys collected data among 330 participants (65.9 % male; 63.9 % non-Hispanic white) whose initial use of any opioid was a pharmaceutical opioid. Retrospective discrete-time survival analysis identified predictors of heroin initiation, measured as self-reported age of first heroin use. RESULTS: Median age of first pharmaceutical opioid use was 17 years; 50.6 % initially acquired pharmaceutical opioids from an illicit source, 56.7 % first used pharmaceutical opioids for recreational purposes, and 86 % initiated heroin use. Average time from first pharmaceutical opioid use to first heroin use was 8.2 years. Drug/alcohol treatment (adjusted Hazard Ratio [aHR]: 0.67, 95 % CI: 0.50, 0.88) was associated with delayed time to heroin initiation. Obtaining opioids from non-medical sources (aHR: 2.21, 95 % CI: 1.55, 3.14) was associated with accelerated time to heroin initiation. Reporting supply problems with obtaining pharmaceutical opioids (e.g., unable to acquire pharmaceutical opioids) was associated with accelerated time to heroin initiation, but the magnitude of this effect was dependent on one's history of methamphetamine use (p < 0.05). CONCLUSIONS: Time to heroin initiation following pharmaceutical opioid use was accelerated among those reporting supply problems and delayed among those with exposure to substance use treatment. Interventions interrupting supply of opioids might benefit from coordination with evidence-based medication-assisted treatment to minimize the risk of transitioning to heroin use, particularly among those with a long history of non-prescribed pharmaceutical opioid use.

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Annual antigen testing is a mainstay for diagnosing infection with Dirofiliaria immitis in dogs; yet, it has been documented that some heartworm-infected dogs and cats test false-negative for antigen due to the presence of antigen-antibody complexes. Several studies have reported the use of heat as a reliable means of immune-complex dissociation (ICD) in recent years; however, the data regarding the use of acid as a reliable method of ICD for D. immitis detection are limited. The objective of this study was to compare an acid-based form of ICD to the more established and evaluated method of heat-based ICD in experimentally infected and non-infected dogs. Plasma from class A dogs experimentally infected ∼4 months prior with D. immitis (infected; n = 24) and dogs reared indoors with no history of exposure to mosquitoes (non-infected; n = 75) were evaluated for presence of D. immitis antigen (DiroCHEK® Heartworm antigen test kit). Each sample was divided into three aliquots for testing: [1] Control plasma (no acid- or heat-treatment), [2] acid-treated plasma (trichloroacetic acid (TCA), incubation, centrifugation for 5 min at 16,000 X g, buffer), and [3] heat-treated plasma (104 °C followed by centrifugation at 16,000 X g). Treatments for each aliquot were performed and tested in triplicate; results were determined both visually (color change) and by spectrophotometric analysis (optical density [OD] value). Of the 24 infected dogs, 0/24 tested positive for antigen in the absence of acid- or heat-treatment. Those same plasma samples following processing by either acid- or heat-treatment yielded 18/24 (75.0%) and 19/24 (79.2%) antigen-positive results, respectively. Of the 75 plasma samples from non-infected dogs, neither acid- nor heat-treatment of plasma caused any false-positive color changes or spectrophotometric values. These results indicate that acid as a means of ICD reliably allowed for the detection of D. immitis antigen in infected plasma while not inducing false-positive results in non-infected plasma samples.

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Common chronic conditions are routinely treated following standardised procedures known as clinical guidelines. For patients suffering from two or more chronic conditions, known as multimorbidity, several guidelines have to be applied simultaneously, which may lead to severe adverse effects when the combined recommendations and prescribed medications are inconsistent or incomplete. This paper presents an automated formal framework to detect, highlight and resolve conflicts in the treatments used for patients with multimorbidities focusing on medications. The presented extended framework has a front-end which takes guidelines captured in a standard modelling language and returns the visualisation of the detected conflicts as well as suggested alternative treatments. Internally, the guidelines are transformed into formal models capturing the possible unfoldings of the guidelines. The back-end takes the formal models associated with multiple guidelines and checks their correctness with a theorem prover, and inherent inconsistencies with a constraint solver. Key to our approach is the use of an optimising constraint solver which enables us to search for the best solution that resolves/minimises conflicts according to medication efficacy and the degree of severity in case of harmful combinations, also taking into account their temporal overlapping. The approach is illustrated throughout with a real medical example.

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Although mammalian sex determination is normally specified genetically by an XX or XY chromosome complement, germ cells develop as sperm or oocytes in response to molecular cues provided by the gonadal somatic cells. In an ovary, germ cells enter meiosis during fetal life, thereby committing to oogenesis. In a testis, germ cells do not enter meiosis until after birth, at puberty. Recent findings indicate that, in mice, the sex-specific timing of entry into meiosis is governed by the balance between 2 secreted signalling molecules, retinoic acid (RA), which promotes entry into meiosis, and fibroblast growth factor 9 (FGF9), which counteracts RA. The combined action of these 2 molecular regulators provides a safety mechanism to guard against germ cell dysregulation that can lead to infertility or germ cell cancers.

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Contactless measurements of water temperature are utilized in a number of sciences, such as oceanography, climatology, and biology. Previously reported Raman spectroscopy techniques exploited the changes in the shapes of water Raman bands. Interpretation of these changes is difficult since these bands are composed of multiple lines, each influenced not only by temperature but also by pressure and salinity. This paper presents a proof-of-principal demonstration of a contactless technique which determines water temperature from the ratio of Stokes and anti-Stokes intensities of the water 180 cm(-1) Raman band. This ratio is not sensitive to pressure and salinity, allowing reliable determination of water temperature.

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WNT signalling plays a central role in mammalian sex determination by promoting ovarian development and repressing aspects of testis development in the early gonad. Dickkopf homolog 1 (DKK1) is a WNT signalling antagonist that plays critical roles in multiple developmental systems by modulating WNT activity. Here, we examined the role of DKK1 in mouse sex determination and early gonadal development. Dkk1 mRNA was upregulated sex-specifically during testis differentiation, suggesting that DKK1 could repress WNT signalling in the developing testis. However, we observed overtly normal testis development in Dkk1-null XY gonads, and found no significant upregulation of Axin2 or Sp5 that would indicate increased canonical WNT signalling. Nor did we find significant differences in expression of key markers of testis and ovarian development. We propose that DKK1 may play a protective role that is not unmasked by loss-of-function in the absence of other stressors.

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AIMS: The 'DRIVER' study was designed to investigate the 'real-world' effectiveness of aliskiren-based treatment of hypertension. This article reports the 180-day blood pressure (BP) outcomes, and the multilevel (physician- and patient-level) determinants thereof. METHODS AND RESULTS: DRIVER was a prospective, observational, open-label, multi-centre, pharmaco-epidemiologic study of hypertensive patients treated with aliskiren in whom prior treatment failed or was not tolerated. 2070 patients (enrolled by 426 physicians) were enrolled; 1695 patients (81.9%) completed the 180-day aliskiren treatment period. Mean patient age was 64.2 ± 12.1 years; 53.7% were men, 25.3% diabetic and 40.7% had a high or very high cardiovascular (CV) risk. At 180 days, the mean ± SD reductions in systolic and diastolic BP were -22.9 ± 16.7 mmHg and -10.5 ± 10.9 mmHg respectively (both p < .001). 2007 and 2009 guideline-defined BP control was achieved in 36.4% and 56.3% of patients, respectively (both p < .001). 64.2% of eligible patients had a reduction in CV risk (p < .001). A physician-level class effect was responsible for 22.8% and 28.1% of variability in systolic and diastolic BP, respectively, for 20.1% of variability in BP control, and for 16.1% of variability in the reduction of CV risk. Both patient- (e.g. adherence) and physician-related factors (e.g. age and knowledge) were significant in profiling best response to treatment with aliskiren. Adverse events reported in this article were consistent with the aliskiren scientific leaflet. CONCLUSION: Aliskiren is safe and effective in reducing BP, improving BP control and reducing global CV risk in a 'real-world' setting and for patients in whom prior treatment failed or was not tolerated. Optimising treatment adherence and strategic medical education may be ways of improving BP outcomes in patients with hypertension.

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Our current understanding of the molecular basis of sex determination and gonadal development in humans is mostly an extrapolation of knowledge gained from studies in the mouse. However, the timing of gene expression in the mouse is unusual among mammals, and it is therefore important that data from other models are also available to help elucidate this pivotal process in human development. Here we describe the sequence of molecular and morphological events marking testis differentiation in bovine embryos. The genital ridges first appeared at CRL 12 (day 32). SRY expression began at CRL 18 (day 37) and peaked at CRL 20 (day 39), leading to a cascade of regulatory, signaling, and steroidogenic gene expression at later stages, detected by quantitative real-time RT-PCR and immunohistochemistry. Testis cords were distinguishable at CRL 27 (day 42). We conclude that the timing of gene expression observed in developing human embryos is much more similar to bovine development than it is to the mouse. Therefore, Bos taurus may represent a useful model in which to study gene expression during sex determination, relevant to human development.

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The study of the mammalian sex-determining pathway has been hampered by the lack of cell culture systems to investigate the underlying molecular relationships between sex-determining genes. Recent approaches using high-throughput genome-wide studies have revealed a number of sexually dimorphic genes expressed in the developing mouse gonad. Here, we investigated a human testicular cell line in terms of its expression of known sex-determining genes and newly identified candidates. The human embryonal carcinoma cell line NT2/D1 was screened for the expression of 46 genes with known or potential roles in the sex-determining and differentiation pathway. Forty genes tested were expressed in NT2/D1 cells including the testis-determining genes SRY, SOX9, SF-1, DHH and FGF9. Genes not expressed included WT1, DAX1 and the ovary-specific genes FOXL2 and WNT4. Cell-specific markers demonstrate that NT2/D1 cells reflect a number of cell types in the gonad including Sertoli, Leydig and germ cells. Our results suggest that male pathways initiated by SRY, SOX9 and SF-1 remain intact in these cells. Lack of expression of ovary-specific genes is consistent with a commitment of these cells to the male lineage. Manipulation of gene expression in this cell line could be an important new in vitro tool for the discovery of new human sex-determining genes.

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We identified a transcript named 11M2 on the basis of its strong male-specific expression pattern in the developing mouse gonad. 11M2 was found to be expressed by gonad primordial germ cells (PGCs) of both sexes and down-regulated in female PGCs as they enter prophase I of the first meiotic division, similar to the expression of OCT4. Mouse EST analysis revealed expression only in early-stage embryos, embryonic stem cells and pre-meiotic germ cells. 11M2 corresponds to a recently reported gene variously known as PGC7, STELLA or DPPA3. We have identified the human orthologue of DPPA3 and find by human EST analysis that it is expressed in human testicular germ cell tumours but not in normal human somatic tissues. The expression patterns of mouse and human DPPA3, in undifferentiated embryonic cells, embryonic germ cells and adult germ cell tumours, together suggest a role for this gene in maintaining cell pluripotentiality.

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WT1 and SOX9 are transcription factors with critical roles in mammalian sex determination and gonadal development. Recent studies in vivo clarify the roles of two alternative splice isoforms of WT1, and demonstrate that SOX9 can induce male sex determination.

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Sry, a gene from the Y chromosome, is known to initiate testis formation and subsequent male differentiation in mammals. A related gene, Sox9, also plays a critical role in testis determination, possibly in all vertebrates. A number of models have been presented regarding the molecular modes of action of these two genes. However, details regarding their regulation, regulatory target genes, and interacting protein factors and co-factors have not been established with any certainty. In this review, we examine new evidence and re-examine existing evidence bearing on these issues, in an effort to build up an integrative model of the network of gene activity centred around Sry and Sox9. J. Exp. Zool. 290:463-474, 2001.

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Little is known of the mechanisms whereby the mammalian indifferent gonad develops into a testis or ovary. In XY individuals, Sry, the mammalian testis-determining gene, is expressed in the pre-Sertoli cells, which then differentiate into Sertoli cells. Other cell types, which include the germ cells, the steroidogenic cells and the connective tissue cells, must then be instructed to develop in a male-specific manner. Although some genes involved in sex-determination and differentiation processes have been identified, we know little of how they interact and cooperate to orchestrate the development of a testis or ovary. We have initiated an expression-screening program designed to identify additional genes, known or novel, which play a role in these processes. This approach is based on our belief that many of the genes we seek will be expressed in a sex-specific manner during the period of sex-determination and differentiation. Most of the genes identified previously are transcription factors and so we aim, in particular, to find genes involved in cell-to-cell communication, signal transduction, and transcriptional regulation, downstream of the differentiation of Sertoli cells. We have used a suppression subtractive-hybridization method to generate male- and female-enriched probes and libraries. Clones are validated as being sex-specific in their expression patterns by array screening and in situ hybridization. Here we report on our progress to date and the general applicability of the approach for studies in other systems. J. Exp. Zool. 290:517-522, 2001.

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Three new asexual yeast species were isolated from various floricolous insects. Candida cleridarum sp. nov. was the dominant species in clerid beetles collected in flowers of various cacti in Arizona and Southern California. The sequence of the D1D2 domains of the large-subunit rDNA showed that it is a sister species to Candida fragi (0.9% base difference), a yeast isolated once from fermenting strawberries. Candida tilneyi sp. nov. and Candida powellii sp. nov. were recovered from bees and from nitidulid beetles in flowers of two species of morning glory (Ipomoea) in north-western Costa Rica. C. tilneyi sp. nov. is most closely related to Candida geochares, but differs in the D1D2 sequence by 4.7% base substitutions. C. powellii sp. nov. is a relative of Candida batistae and Candida floricola, showing sequence differences of 5.9 and 6.9%, respectively. In all cases, the new species are phenotypically similar to their nearest relatives, but are sufficiently different to allow conventional identification. The type strains are C. cleridarum strain UWO(PS) 99-101.1T ( = CBS 8793T), C. tilneyi strain UWO(PS) 99-325.1T ( = CBS 8794T) and C. powellii strain UWO(PS) 99-325.3T ( = CBS 8795T).

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OBJECTIVE: Increasing evidence supports that the sentinel node (SN) is at greatest risk for harboring metastatic disease. This study describes a novel technique to identify the SN in colorectal carcinoma. METHODS: Within 30 minutes of resection, colorectal specimens were injected submucosally with isosulfan blue in four quadrants. Blue lymphatic channels were identified in the mesentery and followed to the blue-stained SN(s), which were then harvested. The specimen was fixed in formalin and subsequently analyzed in the usual fashion. Blue-stained nodes that were negative by hematoxylin and eosin staining were further analyzed by immunohistochemical staining. RESULTS: During a 6-month period, 26 patients with adenocarcinoma of the colon and rectum undergoing routine resection were studied. There were 18 men and 8 women ranging in age from 29 to 86 years (median 66). Blue-stained SNs were identified in 24 of 26 specimens. The mean number of SNs identified per patient was 2.8 +/- 1.6. Seventy-three SNs were identified from a total of 479 lymph nodes harvested. The mean number of nodes identified per patient was 18.4 +/-7. A total of 67 lymph nodes in 12 patients were identified by hematoxylin and eosin staining to have evidence of metastatic disease. Fourteen (20%) of these nodes in six patients were stained blue. However, with immunohistochemical staining, only one blue node did not have evidence of metastatic tumor in a lymphatic basin with tumor present. Four patients (29%) whose lymphatic basins were negative by hematoxylin and eosin staining were upstaged by immunohistochemical staining of the SN. CONCLUSIONS: Ex vivo mapping of the colon and rectum is technically feasible and may provide a useful approach to the ultrastaging of colorectal carcinoma.

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