Metabolism of glucose activates TORC1 through multiple mechanisms in Saccharomyces cerevisiae.

Target of Rapamycin Complex 1 (TORC1) is a conserved eukaryotic protein complex that links the presence of nutrients with cell growth. In Saccharomyces cerevisiae, TORC1 activity is positively regulated by the presence of amino acids and glucose in the medium. However, the mechanisms underlying nutrient-induced TORC1 activation remain poorly understood. By utilizing an in vivo TORC1 activation assay, we demonstrate that differential metabolism of glucose activates TORC1 through three distinct pathways in yeast. The first "canonical Rag guanosine triphosphatase (GTPase)-dependent pathway" requires conversion of glucose to fructose 1,6-bisphosphate, which activates TORC1 via the Rag GTPase heterodimer Gtr1GTP-Gtr2GDP. The second "non-canonical Rag GTPase-dependent pathway" requires conversion of glucose to glucose 6-phosphate, which activates TORC1 via a process that involves Gtr1GTP-Gtr2GTP and mitochondrial function. The third "Rag GTPase-independent pathway" requires complete glycolysis and vacuolar ATPase reassembly for TORC1 activation. We have established a roadmap to deconstruct the link between glucose metabolism and TORC1 activation.

A Trans Youth of Color Study to Measure Health and Wellness: Protocol for a Longitudinal Observation Study.

BACKGROUND: Growing research on transgender youth is accounting for the variety of ways in which young people define their genders and sexualities. Because of this growing representation, more research is needed to understand how intersectional identities and stigma affect risk for HIV acquisition along the HIV care continuum and engagement in mental and physical health care. Little is known about accessibility to HIV-related prevention services of nonbinary and transmasculine youth, and further understanding of the impacts on transfeminine people-those who have historically faced the highest prevalence of HIV positivity-is crucial. OBJECTIVE: The overarching aims of the Trans Youth of Color Study are to conduct longitudinal research with a cohort of transgender minority youth (TGMY), explore factors that aid in the prevention of new HIV infection and transmission, and reduce HIV- and AIDS-related disparities by focusing on successful engagement in care. Findings from this research will be used to inform the development of new interventions designed to engage TGMY in the HIV prevention and care continua. METHODS: Longitudinal research (baseline and follow-up assessments every 6 months for 3 waves of data collection) followed a cohort (N=108) of transgender youth of color recruited in Los Angeles, California, United States. Participants were recruited using multiple community-informed strategies, such as from local venues, social media, and participant referral. In addition to self-report surveys, urine was collected to assess recent use of illicit drugs, and blood, rectal, and throat swabs were collected to test for current sexually transmitted infection and HIV infection. Additional blood and plasma samples (10 mL for 4 aliquots and 1 pellet) were collected and stored for future research. RESULTS: Participants in the Trans Youth of Color Study were recruited between May 25, 2018, and December 7, 2018. Baseline and longitudinal data are being analyzed as of August 2022. CONCLUSIONS: The findings from this research will inform adaptations to existing evidence-based HIV prevention interventions and help to guide new interventions designed to engage TGMY, especially those who are Black, Indigenous, or people of color, in the HIV prevention and care continua. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/39207.

Diethyl phthalate (DEP) perturbs nitrogen metabolism in Saccharomyces cerevisiae.

Phthalates are ubiquitously used as plasticizers in various consumer care products. Diethyl phthalate (DEP), one of the main phthalates, elicits developmental and reproductive toxicities but the underlying mechanisms are not fully understood. Chemogenomic profiling of DEP in S. cerevisiae revealed that two transcription factors Stp1 and Dal81 involved in the Ssy1-Ptr5-Ssy5 (SPS) amino acid-sensing pathway provide resistance to DEP. Growth inhibition of yeast cells by DEP was stronger in poor nitrogen medium in comparison to nitrogen-rich medium. Addition of amino acids to nitrogen-poor medium suppressed DEP toxicity. Catabolism of amino acids via the Ehrlich pathway is required for suppressing DEP toxicity. Targeted metabolite analyses showed that DEP treatment alters the amino acid profile of yeast cells. We propose that DEP inhibits the growth of yeast cells by affecting nitrogen metabolism and discuss the implications of our findings on DEP-mediated toxic effects in humans.

Attention-deficit/hyperactivity disorder (ADHD) and anxiety during the COVID-19 pandemic: Implications for internalizing behaviors in college students.

Objective: The purpose of this study was to delineate the moderating roles of negative experiences related to the coronavirus disease 2019 (COVID-19) on the association between Attention-Deficit/Hyperactivity Disorder symptoms and anxiety symptoms and internalizing behaviors during Fall 2020.Method: Participants were 200 college students. Using a moderated moderation model, researchers found that attention-deficit/hyperactivity disorder symptoms predicted anxiety symptoms for those who internalized behaviors and experienced COVID-19 more negatively.Results: Results suggested that ADHD symptoms were playing a role in the manifestation of anxiety symptoms during the COVID-19 pandemic and that college students who internalize behaviors experienced worsened ADHD symptoms.Conclusion: Clinical implications underscore the importance of providing mental health resources for students on campus, particularly during the COVID-19 pandemic. Specialized treatment may include help with developing time management skills and teaching interventions such as mindfulness exercises that may help alleviate anxiety and improve attention and concentration.

The Importance of Decarbonylation Mechanisms in the Atomic Layer Deposition of High-Quality Ru Films by Zero-Oxidation State Ru(DMBD)(CO)3.

Achieving facile nucleation of noble metal films through atomic layer deposition (ALD) is extremely challenging. To this end, η4 -2,3-dimethylbutadiene ruthenium(0) tricarbonyl (Ru(DMBD)(CO)3 ), a zero-valent complex, has recently been reported to achieve good nucleation by ALD at relatively low temperatures and mild reaction conditions. The authors study the growth mechanism of this precursor by in situ quartz-crystal microbalance and quadrupole mass spectrometry during Ru ALD, complemented by ex situ film characterization and kinetic modeling. These studies reveal that Ru(DMBD)(CO)3 produces high-quality Ru films with excellent nucleation properties. This results in smooth, coalesced films even at low film thicknesses, all important traits for device applications. However, Ru deposition follows a kinetically limited decarbonylation reaction scheme, akin to typical chemical vapor deposition processes, with a strong dependence on both temperature and reaction timescale. The non-self-limiting nature of the kinetically driven mechanism presents both challenges for ALD implementation and opportunities for process tuning. By surveying reports of similar precursors, it is suggested that the findings can be generalized to the broader class of zero-oxidation state carbonyl-based precursors used in thermal ALD, with insight into the design of effective saturation studies.

TORC1 regulates the transcriptional response to glucose and developmental cycle via the Tap42-Sit4-Rrd1/2 pathway in Saccharomyces cerevisiae.

BACKGROUND: Target of Rapamycin Complex 1 (TORC1) is a highly conserved eukaryotic protein complex that couples the presence of growth factors and nutrients in the environment with cellular proliferation. TORC1 is primarily implicated in linking amino acid levels with cellular growth in yeast and mammals. Although glucose deprivation has been shown to cause TORC1 inactivation in yeast, the precise role of TORC1 in glucose signaling and the underlying mechanisms remain unclear. RESULTS: We demonstrate that the presence of glucose in the growth medium is both necessary and sufficient for TORC1 activation. TORC1 activity increases upon addition of glucose to yeast cells growing in a non-fermentable carbon source. Conversely, shifting yeast cells from glucose to a non-fermentable carbon source reduces TORC1 activity. Analysis of transcriptomic data revealed that glucose and TORC1 co-regulate about 27% (1668/6004) of yeast genes. We demonstrate that TORC1 orchestrates the expression of glucose-responsive genes mainly via the Tap42-Sit4-Rrd1/2 pathway. To confirm TORC1's function in glucose signaling, we tested its role in spore germination, a glucose-dependent developmental state transition in yeast. TORC1 regulates the glucose-responsive genes during spore germination and inhibition of TORC1 blocks spore germination. CONCLUSIONS: Our studies indicate that a regulatory loop that involves activation of TORC1 by glucose and regulation of glucose-responsive genes by TORC1, mediates nutritional control of growth and development in yeast.

High-Throughput Screening and Automated Data-Driven Analysis of the Triplet Photophysical Properties of Structurally Diverse, Heteroleptic Iridium(III) Complexes.

Steady state emission spectra and excited state lifetimes were measured for 1440 distinct heteroleptic [Ir(C^N)2(N^N)]+ complexes prepared via combinatorial parallelized synthesis; 72% of the complexes were found to be luminescent, and the emission maxima of the library spanned the visible spectrum (652-459 nm). Spectral profiles ranged from broad structureless bands to narrow emissions exhibiting vibrational substructure. Measured excited state lifetimes ranged between ∼0.1-14 µs. Automated emission spectral fitting with successive Gaussian functions revealed four distinct measured classes of excited states; in addition to well understood metal-ligand to ligand-charge transfer (3MLLCT) and ligand-centered (3LC) excited states, our classification also identified photophysical characteristics of less explored mixed 3MLLCT/3LC states. Electronic structure features obtained from DFT calculations performed on a large subset of these Ir(III) chromophores offered clear insights into the excited state properties and allowed the prediction of structure/luminescence relationships in this class of commonly used photocatalysts. Models with high prediction accuracy (R2 = 0.89) for emission color were developed on the basis of experimental data. Furthermore, different degrees of nuclear reorganization in the excited state were shown to significantly impact emission energy and excited state lifetimes.

Perceived Instability Is Associated With Strength and Pain, Not Frontal Knee Laxity, in Patients With Advanced Knee Osteoarthritis.

BACKGROUND: Increased varus/valgus laxity and perceived knee instability are independently associated with poor outcomes in people with knee osteoarthritis. However, the relationship between laxity and perceived instability is unclear. OBJECTIVE: To assess whether knee extensor strength, pain, and knee laxity are related to perceived knee instability in patients with advanced knee osteoarthritis. METHODS: This was a secondary analysis of a prospective observational cohort study of 35 patients (24 female; mean ± SD age, 60 ± 8 years; body mass index, 33 ± 5 kg/m2) with knee osteoarthritis awaiting total knee arthroplasty (36 knees). Within 1 month before arthroplasty, we measured isometric knee extension strength and self-reported knee pain (using the Knee injury and Osteoarthritis Outcome Score pain subscale). Patients rated their perception of knee instability as moderate to severe (n = 20) or slight to none (n = 15 patients, n = 16 knees) using the Knee Outcome Survey. We measured intraoperative varus/valgus knee laxity. RESULTS: Lower knee extension strength (P = .01) and greater pain (P<.01) were associated with the perception of moderate to severe knee instability. Laxity was not related to perceived knee instability (P = .63). CONCLUSION: Knee extension strength and pain were associated with perceived instability in people with advanced osteoarthritis. Varus/valgus laxity was not related to perceived knee instability. LEVEL OF EVIDENCE: Level 2, prognostic. J Orthop Sports Phys Ther 2019;49(7):513-517. doi:10.2519/jospt.2019.8619.

Forces Generated by Vastus Lateralis and Vastus Medialis Decrease with Increasing Stair Descent Speed.

Stair descent (SD) is a common, difficult task for populations who are elderly or have orthopaedic pathologies. Joint torques of young, healthy populations during SD increase at the hip and ankle with increasing speed but not at the knee, contrasting torque patterns during gait. To better understand the sources of the knee torque pattern, we used dynamic simulations to estimate knee muscle forces and how they modulate center of mass (COM) acceleration across SD speeds (slow, self-selected, and fast) in young, healthy adults. The vastus lateralis and vastus medialis forces decreased from slow to self-selected speeds as the individual lowered to the next step. Since the vasti are primary contributors to vertical support during SD, they produced lower forces at faster speeds due to the lower need for vertical COM support observed at faster speeds. In contrast, the semimembranosus and rectus femoris forces increased across successive speeds, allowing the semimembranosus to increase acceleration downward and forward and the rectus femoris to provide more vertical support and resistance to forward progression as SD speed increased. These results demonstrate the utility of dynamic simulations to extend beyond traditional inverse dynamics analyses to gain further insight into muscle mechanisms during tasks like SD.

Relationships between varus-valgus laxity of the severely osteoarthritic knee and gait, instability, clinical performance, and function.

Increased varus-valgus laxity has been reported in individuals with knee osteoarthritis (OA) compared to controls. However, the majority of previous investigations may not report truly passive joint laxity, as their tests have been performed on conscious participants who could be guarding against motion with muscle contraction during laxity evaluation. The purpose of this study was to investigate how a measure of passive knee laxity, recorded when the participant is under anesthesia, is related to varus-valgus excursion during gait, clinical measures of performance, perceived instability, and self-reported function in participants with severe knee OA. We assessed passive varus-valgus knee laxity in 29 participants (30 knees) with severe OA, as they underwent total knee arthroplasty (TKA). Participants also completed gait analysis, clinical assessment of performance (6-min walk (6 MW), stair climbing test (SCT), isometric knee strength), and self-reported measures of function (perceived instability, Knee injury, and Osteoarthritis Outcome Score (KOOS) a median of 18 days before the TKA procedure. We observed that greater passive varus-valgus laxity was associated with greater varus-valgus excursion during gait (R2 = 0.34, p = 0.002). Significant associations were also observed between greater laxity and greater isometric knee extension strength (p = 0.014), farther 6 MW distance (p = 0.033) and shorter SCT time (p = 0.046). No relationship was observed between passive varus-valgus laxity and isometric knee flexion strength, perceived instability, or any KOOS subscale. The conflicting associations between laxity, frontal excursion during gait, and functional performance suggest a complex relationship between laxity and knee cartilage health, clinical performance, and self-reported function that merits further study. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1644-1652, 2017.

Use of the Menopause-Specific Quality of Life (MENQOL) questionnaire in research and clinical practice: a comprehensive scoping review.

OBJECTIVE: The Menopause-Specific Quality of Life (MENQOL) questionnaire was developed as a validated research tool to measure condition-specific QOL in early postmenopausal women. We conducted a comprehensive scoping review to explore the extent of MENQOL's use in research and clinical practice to assess its value in providing effective, adequate, and comparable participant assessment information. METHODS: Thirteen biomedical and clinical databases were systematically searched with "menqol" as a search term to find articles using MENQOL or its validated derivative MENQOL-Intervention as investigative or clinical tools from 1996 to November 2014 inclusive. Review articles, conference abstracts, proceedings, dissertations, and incomplete trials were excluded. Additional articles were collected from references within key articles. Three independent reviewers extracted data reflecting study design, intervention, sample characteristics, MENQOL questionnaire version, modifications and language, recall period, and analysis detail. Data analyses included categorization and descriptive statistics. RESULTS: The review included 220 eligible papers of various study designs, covering 39 countries worldwide and using MENQOL translated into more than 25 languages. A variety of modifications to the original questionnaire were identified, including omission or addition of items and alterations to the validated methodological analysis. No papers were found that described MENQOL's use in clinical practice. CONCLUSIONS: Our study found an extensive and steadily increasing use of MENQOL in clinical and epidemiological research over 18 years postpublication. Our results stress the importance of proper reporting and validation of translations and variations to ensure outcome comparison and transparency of MENQOL's use. The value of MENQOL in clinical practice remains unknown.

Changes in lower extremity peak angles, moments and muscle activations during stair climbing at different speeds.

Stair climbing is a common daily activity, yet there is no basic knowledge on how lower extremity joint angles, moments or muscle activations are affected by stair climbing speed. This information will determine whether speed matching is necessary for stair climbing studies. Moreover, changes in lower extremity biomechanics during stair climbing at different speeds will aid in the clinical interpretation of a patient's maximal stair climbing speed. Thirty healthy participants provided consent. Kinematics, kinetics, and muscle activations were collected on a three step staircase. Subjects climbed the staircase at normal, slow and fast self-selected speeds. Linear mixed models for repeated measures were used to study the associations between speed and the lower extremity peak joint angles and moments, and muscle activations. The peak hip flexion and extension moments increased with increasing speed, while peak knee flexion moment did not vary consistently with speed. The peak muscle activations varied consistently with respect to the sagittal plane kinetics. These results suggest that in healthy subjects, the hip is the greatest contributor when modulating stair climbing speed, while additional knee contributions do not appear necessary to increase speed. Further stair studies should consider speed matching in order to accurately assess biomechanical differences.

Extending the olive branch.

Using data from a study of qualitative researchers' experiences with ethics review and our own lens as both researchers and REB/IRB members, we explore the ethics review process and provide recommendations for improvements. Our findings suggest that the review process would benefit from a strengthened trust relationship between REB/IRBs and qualitative researchers that would require a commitment from both sides. Regarding REBs/IRBs, increased transparency of the review process, consistent application of federal guidelines, and a more collaborative review approach may improve the trust of qualitative researchers. Regarding researchers, approaching ethics review as a form of academic peer review, similar to other types of assessments of scholarly products such as grants and publications, may promote the integration of ethics review as an intrinsic part of the research process. Recognizing that responsibility for ethical research is a shared goal of both researchers and REB/IRBs, improved collaboration and constructive interaction can assist in understanding each other's perspective and work toward the development of mutual trust and respect.

The efficacy of axillary ultrasound in the detection of nodal metastasis in breast cancer.

OBJECTIVE: Recent reports indicate a lack of survival benefit for axillary lymph node dissection (ALND) versus sentinel lymph node biopsy in early breast cancer. To study this issue further, we assessed the accuracy and effectiveness of ultrasound examination in detecting axillary nodal involvement in breast cancer patients with the aim of refining our current clinical pathways. MATERIALS AND METHODS: Ultrasound data were collected from breast cancer cases over 3 years. Images were reviewed by experienced radiologists and the following characteristics were assessed: size, morphology, hyperechoic hilum, and cortical thickness of the ipsilateral axillary nodes. The findings were correlated with histologic outcomes after ALND. RESULTS: Two hundred twenty-four cases were included in the analysis, 113 (50.4%) of which had evidence of metastatic nodal involvement at final histology. Of these 113 cases, ultrasound findings for 59 (52.2%) were positive. The overall positive predictive value of ultrasound for detecting metastatic nodal involvement measured 0.81. The negative predictive value was 0.60. The sensitivity was 53.7%; specificity, 85.1%; and accuracy, 67.9%. The ultrasound morphologic lymph node features with the greatest correlation with malignancy were the absence of a hyperechoic hilum (p = 0.003) and increased cortical thickness (p = 0.03). Patients with a metastatic nodal burden density of at least 20% were more likely to have abnormal findings on axillary ultrasound examination (p = 0.009). CONCLUSION: Axillary ultrasound has a low negative predictive value and negative ultrasound results do not exclude axillary node metastases with sufficient sensitivity to justify its routine clinical use. Clinical pathways need to consider an evidence-based approach, focusing on the criteria by which we select breast cancer patients for ALND.

The clinico-pathologic role of microRNAs miR-9 and miR-151-5p in breast cancer metastasis.

BACKGROUND: MicroRNAs (miRNAs) may function as suppressors or promoters of tumor metastasis according to their messenger RNA targets. Previous studies have suggested that miR-9 and miR-151-5p are associated with metastasis in breast cancer and hepatocellular carcinoma, respectively. We aimed to further establish the potential roles of miR-9 and miR-151-5p in tumor invasion and metastasis and investigate their use as biomarkers. METHODS: We used quantitative real-time PCR (qRT-PCR) to measure differences in miR-9 and miR-151-5p expression between primary breast tumors and their lymph-node metastases in 194 paired tumor samples from 97 patients. We also correlated expression levels with histologic data to investigate their utility as biomarkers. RESULTS: There were no significant differences in miR-9 expression between the primary tumors and lymph nodes; however, miR-151-5p expression was significantly lower in the lymph-node metastases than in their corresponding tumors (p < 0.05). miR-9 levels were elevated in primary breast tumors from patients diagnosed with higher-grade tumors (p < 0.05); however, no differences were observed in miR-151-5p levels between different grades of tumor. Interestingly, miR-9 levels were elevated in invasive lobular carcinomas (ILC) compared with invasive ductal carcinomas (IDC; p < 0.01). CONCLUSIONS: In aggregate, these data suggest that miR-151-5p upregulation may suppress metastasis in primary breast tumors. Both miRNAs may serve as useful biomarkers in future clinical trials in breast cancer.

Biological basis of [¹¹C]choline-positron emission tomography in patients with breast cancer: comparison with [¹8F]fluorothymidine positron emission tomography.

OBJECTIVE: The biological significance of [¹¹C]choline (CHO) uptake in human tumours is unclear and probably linked to choline kinase-α (CHKα) expression and cell proliferation. We directly compared CHO with [¹8F]fluorothymidine (FLT), an imaging biomarker of proliferation, by positron emission tomography (PET) in patients with breast cancer to investigate whether cell proliferation is an important determinant of CHO uptake. Furthermore, we evaluated CHKα and the Ki67-labelling index (LIKi67) in tumour biopsies. METHODS: Sequential CHO-PET and FLT-PET within the same imaging session were performed in 21 patients with oestrogen receptor (ER)-positive breast cancer (28 lesions). Average and maximum CHO standardized uptake values (SUV) at 60 min: SUV60,av, and SUV60,max, and the rate constant of net irreversible uptake, Ki, were compared with FLT uptake at 60 min: SUV60,av and SUV60,max. Biopsies were stained for CHKα and LIKi67 in eight cases. RESULTS: Tumours were equally visible on CHO-PET and FLT-PET imaging. Tumour CHO-PET strongly correlated with FLT imaging variables (Pearson's r=0.83; P<0.0001 for CHO-SUV60,max vs. FLT-SUV60,max). A statistically significant association was found between CHO-PET variables and categorical scores of cytoplasmic CHKα intensity and between FLT-PET and LIKi67 (P<0.05, one-way analysis of variance). CONCLUSION: Choline metabolism and proliferation as assessed by PET were correlated in ER-positive breast cancer, indicating that high CHO uptake is a measure of cellular proliferation in this setting. CHO uptake was also found to be related to cytoplasmic CHKα expression.

The role of colleges and schools of pharmacy in the advent of Healthy People 2020.

As the need for more experiential sites increases, colleges and schools of pharmacy should consider innovative and strategic approaches to expansion including adding programs that would address the target areas emphasized by Healthy People 2020. Healthy People 2020 encompasses the following areas: adolescent health, early and middle childhood, genomics, global health, health information technology, healthcare-associated infections, hearing and other sensory or communicating disorders (ear, nose, throat-voice, speech and language), weight status, older adults, quality of life and well-being, and social determinants of health. Academic leaders should consider what role exists for pharmacy practice in these areas and focus future program and curriculum development on Healthy People 2020 topic areas.

Rising to the challenge: addressing the concerns of people working in the sex industry.

In September 2010, three Canadian Criminal Code provisions related to prostitution were ruled unconstitutional because they increase the risk of harm to people working in the sex industry (PWSI). Using data from studies with PWSI and key informants conducted in several Canadian cities, we examine three domains related to worker health and safety: occupational health and safety, perceptions of and behaviors toward workers, and access to essential services. Addressing these issues necessitates moving beyond decriminalization. We conclude that using a harm reduction/labor rights framework would enhance our ability to address issues related to the physical, social, and mental well-being as well as rights of PWSI.

Epidermal growth factor receptor status in early stage breast cancer is associated with cellular proliferation but not cross-talk.

The epidermal growth factor receptor (EGFR) is a therapeutic target in a number of settings in solid malignancies, but its role in breast cancer has remained unclear and controversial. In 810 primary breast cancers derived from patients suitable for cytotoxic chemotherapy, EGFR was prospectively measured and interactions with tumour and clinical correlates were tested to observe whether postulated cross-talk mechanisms are likely to modulate breast cancer metastasis and proliferation. A minority (79 tumours, 9.8%) were EGFR positive; in a multivariate analysis the likelihood of being EGFR positive was significantly increased for patients with grade 3 disease, compared with grade 1 (OR 15.6; 95% CI 2 to 122, p=0.0001), and for oestrogen receptor-negative status compared with positive (OR 24.1; 95% CI 12.7 to 46.00, p=0.0001). EGFR expression may play a role in breast cancer proliferation, but appears unlikely to modify tumour pathology via postulated mechanisms of oestrogen receptor/EGFR-mediated cross-talk.