Acetyl-methyllysine marks chromatin at active transcription start sites.

Lysine residues in histones and other proteins can be modified by post-translational modifications that encode regulatory information1. Lysine acetylation and methylation are especially important for regulating chromatin and gene expression2-4. Pathways involving these post-translational modifications are targets for clinically approved therapeutics to treat human diseases. Lysine methylation and acetylation are generally assumed to be mutually exclusive at the same residue. Here we report cellular lysine residues that are both methylated and acetylated on the same side chain to form Nε-acetyl-Nε-methyllysine (Kacme). We show that Kacme is found on histone H4 (H4Kacme) across a range of species and across mammalian tissues. Kacme is associated with marks of active chromatin, increased transcriptional initiation and is regulated in response to biological signals. H4Kacme can be installed by enzymatic acetylation of monomethyllysine peptides and is resistant to deacetylation by some HDACs in vitro. Kacme can be bound by chromatin proteins that recognize modified lysine residues, as we demonstrate with the crystal structure of acetyllysine-binding protein BRD2 bound to a histone H4Kacme peptide. These results establish Kacme as a cellular post-translational modification with the potential to encode information distinct from methylation and acetylation alone and demonstrate that Kacme has all the hallmarks of a post-translational modification with fundamental importance to chromatin biology.

bakR: uncovering differential RNA synthesis and degradation kinetics transcriptome-wide with Bayesian hierarchical modeling.

Differential expression analysis of RNA sequencing (RNA-seq) data can identify changes in cellular RNA levels, but provides limited information about the kinetic mechanisms underlying such changes. Nucleotide recoding RNA-seq methods (NR-seq; e.g., TimeLapse-seq, SLAM-seq, etc.) address this shortcoming and are widely used approaches to identify changes in RNA synthesis and degradation kinetics. While advanced statistical models implemented in user-friendly software (e.g., DESeq2) have ensured the statistical rigor of differential expression analyses, no such tools that facilitate differential kinetic analysis with NR-seq exist. Here, we report the development of Bayesian analysis of the kinetics of RNA (bakR; https:// github.com/simonlabcode/bakR), an R package to address this need. bakR relies on Bayesian hierarchical modeling of NR-seq data to increase statistical power by sharing information across transcripts. Analyses of simulated data confirmed that bakR implementations of the hierarchical model outperform attempts to analyze differential kinetics with existing models. bakR also uncovers biological signals in real NR-seq data sets and provides improved analyses of existing data sets. This work establishes bakR as an important tool for identifying differential RNA synthesis and degradation kinetics.

Vascular Endothelial Growth Factor-C Treatment Enhances Cerebrospinal Fluid Outflow during Toxoplasma gondii Brain Infection but Does Not Improve Cerebral Edema.

Cerebral edema frequently develops in the setting of brain infection and can contribute to elevated intracranial pressure, a medical emergency. How excess fluid is cleared from the brain is not well understood. Previous studies have shown that interstitial fluid is transported out of the brain along perivascular channels that collect into the cerebrospinal fluid (CSF)-filled subarachnoid space. CSF is then removed from the central nervous system through venous and lymphatic routes. The current study tested the hypothesis that increasing lymphatic drainage of CSF would promote clearance of cerebral edema fluid during infection with the neurotropic parasite Toxoplasma gondii. Fluorescent microscopy and magnetic resonance imaging was used to show that C57BL/6 mice develop vasogenic edema 4 to 5 weeks after infection with T. gondii. Tracer experiments were used to evaluate how brain infection affects meningeal lymphatic function, which demonstrated a decreased rate in CSF outflow in T. gondii-infected mice. Next, mice were treated with a vascular endothelial growth factor (VEGF)-C-expressing viral vector, which induced meningeal lymphangiogenesis and improved CSF outflow in chronically infected mice. No difference in cerebral edema was observed between mice that received VEGF-C and those that rececived sham treatment. Therefore, although VEGF-C treatment can improve lymphatic outflow in mice infected with T. gondii, this effect does not lead to increased clearance of edema fluid from the brains of these mice.

Microglial STAT1-sufficiency is required for resistance to toxoplasmic encephalitis.

Toxoplasma gondii is a ubiquitous intracellular protozoan parasite that establishes a life-long chronic infection largely restricted to the central nervous system (CNS). Constant immune pressure, notably IFN-γ-STAT1 signaling, is required for preventing fatal pathology during T. gondii infection. Here, we report that abrogation of STAT1 signaling in microglia, the resident immune cells of the CNS, is sufficient to induce a loss of parasite control in the CNS and susceptibility to toxoplasmic encephalitis during the early stages of chronic infection. Using a microglia-specific genetic labeling and targeting system that discriminates microglia from blood-derived myeloid cells that infiltrate the brain during infection, we find that, contrary to previous in vitro reports, microglia do not express inducible nitric-oxide synthase (iNOS) during T. gondii infection in vivo. Instead, transcriptomic analyses of microglia reveal that STAT1 regulates both (i) a transcriptional shift from homeostatic to "disease-associated microglia" (DAM) phenotype conserved across several neuroinflammatory models, including T. gondii infection, and (ii) the expression of anti-parasitic cytosolic molecules that are required for eliminating T. gondii in a cell-intrinsic manner. Further, genetic deletion of Stat1 from microglia during T. gondii challenge leads to fatal pathology despite largely equivalent or enhanced immune effector functions displayed by brain-infiltrating immune populations. Finally, we show that microglial STAT1-deficiency results in the overrepresentation of the highly replicative, lytic tachyzoite form of T. gondii, relative to its quiescent, semi-dormant bradyzoite form typical of chronic CNS infection. Our data suggest an overall protective role of CNS-resident microglia against T. gondii infection, illuminating (i) general mechanisms of CNS-specific immunity to infection (ii) and a clear role for IFN-STAT1 signaling in regulating a microglial activation phenotype observed across diverse neuroinflammatory disease states.

Internally controlled RNA sequencing comparisons using nucleoside recoding chemistry.

Quantitative comparisons of RNA levels from different samples can lead to new biological understanding if they are able to distinguish biological variation from variable sample preparation. These challenges are pronounced in comparisons that require complex biochemical manipulations (e.g. isolating polysomes to study translation). Here, we present Transcript Regulation Identified by Labeling with Nucleoside Analogues in Cell Culture (TILAC), an internally controlled approach for quantitative comparisons of RNA content. TILAC uses two metabolic labels, 4-thiouridine (s4U) and 6-thioguanosine (s6G), to differentially label RNAs in cells, allowing experimental and control samples to be pooled prior to downstream biochemical manipulations. TILAC leverages nucleoside recoding chemistry to generate characteristic sequencing signatures for each label and uses statistical modeling to compare the abundance of RNA transcripts between samples. We verified the performance of TILAC in transcriptome-scale experiments involving RNA polymerase II inhibition and heat shock. We then applied TILAC to quantify changes in mRNA association with actively translating ribosomes during sodium arsenite stress and discovered a set of transcripts that are translationally upregulated, including MCM2 and DDX5. TILAC is broadly applicable to uncover differences between samples leading to improved biological insights.

DIAGNOSIS DISCLOSURE RATE AND ITS ASSOCIATIONS AMONG ADOLESCENTS LIVING WITH HUMAN IMMUNODEFICIENCY VIRUS IN GOMBE METROPOLIS, NIGERIA.

Introduction: Disclosure of Human Immunodeficiency Virus (HIV) status is one of the major challenges in the management of children and adolescents living with HIV (CALHIV). With the increasing number of adolescents living with HIV (ALHIV) and the peculiarities of the adolescent stage of development, there is a need for local data on the disclosure of HIV status among adolescents living with HIV in our area of practice. Objectives: To determine the prevalence of disclosure of HIV status and its associated factors among Adolescents living with HIV in Gombe Metropolis. Methodology: This was a cross-sectional descriptive study among 130 ALHIV aged 12-18 years, attending Antiretroviral Therapy (ART) clinics in Federal Teaching Hospital and State Specialist Hospital- Gombe who were recruited consecutively over 10 months. Disclosure of HIV status was assessed using a pre-tested semi-structured questionnaire in both the adolescents and their respective caregivers. Results: The prevalence of HIV status disclosure by caregivers' report and self-report was 66.2% and 63.1% respectively. Older adolescents' age and a higher level of education were significantly associated with disclosure (p value < 0.05). The commonest reason for disclosure was 'increasing curiosity' 23/130(26.7%) while 'being too young' was the commonest reason for non-disclosure 19/44(43.2%). About half 42/86(48.8%) of the disclosures were done by the mothers while 15/86(17.4%) disclosure processes were carried out by healthcare workers. Conclusion: The disclosure rate was relatively high among ALHIV in the Gombe Metropolis. Caregivers should be encouraged on early disclosure.

CASE FATALITY RATE OF CHILDHOOD TUBERCULOSIS: EXPERIENCE FROM FEDERAL TEACHING HOSPITAL GOMBE: A TWO DECADE REVIEW.

Introduction: Tuberculosis (TB) was the leading cause of death from an infectious agent worldwide, until the Coronavirus (COVID-19) pandemic, ranking above HIV/AIDS. Nigeria ranks 6th among the 30 TB high-burden countries (TB, TB/HIV, DRTB) and 1st in Africa. The estimated case fatality rate (CFR) of TB in Sub-Sahara Africa (SSA) is 15%. Objective: To review the Tuberculosis case fatality rate (TCFR) in children diagnosed with TB from 2000-2019 in Federal Teaching Hospital Gombe. Methodology: All cases of Tuberculosis (TB) diagnosed in children using ICD 10 classification were retrieved and analyzed. These included deaths from TB. The mainstay of TB diagnosis was clinical using TB Score (81%), Gene Xpert was 7%, and AFB was 10%. Results: 26,716 children were admitted; 383 had TB out of which 208(54.3%) were males and 175 (45.7%) females. TB constituted 1.4% of Paediatric admissions. Children 0 -5 years constituted 46.7% (179/383) of cases and 11 - 18 years were 31.3% (120/383). Fulani, Hausa, and Tangale constituted 43.6% (167), 21.1% (81), and 6.8% (26) of TB cases respectively. TB admissions were highest between 2015 and 2019 (31.8%). TB adenitis was the most common extrapulmonary TB. Tuberculosis/HIV co-infection accounted for 103(27%), out of which 74% (44) died. Overall TCFR was 15.6%; TCFR was 16.3% in males and 14.8% in females. The TCFR was 46.7% in 0-5yrs; 15% in 6-9yrs and 38.3% in 10-18yrs.Fulani had the highest CFR (11.9%). Tuberculosis CFR was highest between 2010-2014 (30.0%) and lowest in 2005-2009 (21.6%). Conclusion: The Tuberculosis CFR is comparable to SSA CFR.

REVEALING THE VARIED REALITY OF MALARIA-RELATED DEATHS IN CHILDREN ACROSS GENDER, AGE, AND ETHNICITY IN FEDERAL TEACHING HOSPITAL GOMBE OVER 20 YEARS: AN ESSENTIAL EPIDEMIOLOGIC IMPERATIVE.

Introduction: Nigeria recorded 31% of 619,000 malaria deaths globally and accounts for 25-30% of all childhood mortality in the country. Few studies in Nigeria, have reported malaria's case fatality rate over a long period. Objective: To determine Malaria Case Fatality Rate among Children admitted from 2000-2019. Methodology: All severe malaria cases and deaths amongst children aged 0-18 over the last two decades were analysed using ICD-10. The diagnosis was based on clinical and microscopic findings. Results: 26,716 children were admitted, 2494 (9.3%) were diagnosed with malaria and 209 died. Malaria constituted 5.3% (209/3956) of all childhood mortality. Males constituted 58.9 % (1468/2494) while 65% (1642/2494) were aged 0-5 years. Of the malaria admissions, Fulani and Hausa constituted 948(38%) and 438(17.6%) respectively. Admissions were highest in October (15%) and in 2012 (9.6%). The overall malaria CFR was 8.3%; 8.8% in Females (91/1026) and 8.03% in Males P-value <0.05 (X2=54.735); 8.6% in children aged 0-5years, 8.2% in 6-10 years and 7.4% in 11-18 years, P-value <0.05 (X2=893.164). CFR was highest in April (11.4%)and lowest in November (5.2%). Kanuri and Igbo had CFR of 70% and 38.4% respectively while it was lowest in Tera tribe (4.3%), P-value<0.05. The CFR was highest in the year 2004 (22%), 3.5% in 2000 and 2006. Over the years, case fatality rate was 15.9% between 2000-2004, 6.1% from 2005-2009. Between 2010-2015, it was 7.3% and 8.5% from 2016-2019. Conclusion: This study revealed the deadly reality of severe malaria with increased CFR among females, aged 0-5 and the Kanuri tribe.

EPIDEMIOLOGIC TREND AND CASE FATALITY OF CHILDHOOD TETANUS IN FEDERAL TEACHING HOSPITAL GOMBE; A 20YEARS REVIEW.

Introduction: Tetanus is a vaccine-preventable disease, it remains a significant cause of morbidity and mortality in both neonatal and post-neonatal periods, especially in developing countries with limited health facilities and inadequate vaccination. The overall case fatality rate (CFR) is 13.2% globally, highest in the neonatal period and in sub-Saharan Africa. CFR is 64%, 47%, and 43% in Nigeria, Uganda, and Tanzania respectively. Objectives: To determine the Case Fatality Rate of Childhood tetanus in FTHG from 2000-2019. Methodology: All cases and deaths from tetanus amongst children aged 0-18 years in paediatric medical ward of FTHG over the last two decades diagnosed clinically and classified using ICD-10 were analysed. Results: 95 cases of tetanus out of 26,716 total admissions constituting 0.004%. There were 49 tetanus deaths out of 3956 total childhood deaths (0.012%) over the study period. Males constituted 66% (63/95). 30% (28/95) were aged 0-28 days; 23.1% (22/95) were adolescents. Fulani and Hausa constituted 37% (34/95) and 31% (29/95) respectively. Admission was highest in the dry season 52% (50/95 %). The overall tetanus CFR was 51.6%; 78% of deaths were in males (38/49), 30% in neonates, and 23% in adolescents. CFR was highest during the dry season (67.3%). Hausa and Fulani had CFR of 51% and 40% respectively. P-value <0.05 The CFR was 88% between 2000-2004, 72% from 2005-2009, 71% between 2010-2014 and 33% from 2015-2019. Conclusion: Tetanus CFR is still high among neonates and adolescents. Maternal tetanus vaccine and booster doses in children need strengthening.

IN-PATIENT PNEUMONIA BURDEN AND CASE FATALITY RATES IN CHILDREN OVER TWO DECADES IN FEDERAL TEACHING HOSPITAL, GOMBE (FTHG).

Introduction: Pneumonia is the leading cause of death among children globally accounting for an estimated 1.2 million (18%) total deaths annually. The number of childhood-related deaths from pneumonia is approximately 2000-fold higher in developing than in developed countries. Nigeria contributes the highest of pneumonia-related deaths globally. Objectives: To determine the case fatality rates (CFR) of pneumonia from 2000-2019 in paediatric ward, FTHG. Methodology: All cases of pneumonia admissions and deaths in patients aged 0-18 years, using ICD-10 classification, were retrieved and analysed. The mainstay of diagnosis is clinical and/or radiographic features. Results: A total of 26,716 children were admitted during this period, 1151 had pneumonia (4.3%) and 118 died. Males constituted 647 (56.2%) and females 43.8% of the total pneumonia admissions. Children aged 0-5 years had the highest pneumonia admissions, followed by 6-9 years. Admissions were highest in the wet than the dry season. Pneumonia CFR was 10.2%; 10.9% in females and 9.7% in males. Under-5 constituted 84% (969/1151) of pneumonia admission with a CFR of 9.3%. CFR were 10.3% and 21% in 6-10 years, and 11-18 years respectively. The CFR between2000-2004 was 14.1%, 2005-2009:21.1%, 2010-2014:10.2% and 2015-2019:7.2%. Kanuri had the highest CFR of 56.2%.(P <0.05) Other ethnic groups were 29.4% in Waja, 25% in Tula, 21.4% in Igbo, 16.6% in Yoruba, 12.1% in Tangale, 10.2% in Hausa, 8.8%in Bolewa and 8.3% in Fulani. The CFR was highest in February20.2%. Conclusion: Pneumonia Case fatality is high.

Metabolomic and transcriptomic responses of ticks during recovery from cold shock reveal mechanisms of survival.

Ticks are blood-feeding ectoparasites but spend most of their life off-host where they may have to tolerate low winter temperatures. Rapid cold hardening (RCH) is a process commonly used by arthropods, including ticks, to improve survival of acute low temperature exposure. However, little is known about the underlying mechanisms in ticks associated with RCH, cold shock and recovery from these stresses. In the present study, we investigated the extent to which RCH influences gene expression and metabolism during recovery from cold stress in Dermacentor variabilis, the American dog tick, using a combined transcriptomics and metabolomics approach. Following recovery from RCH, 1860 genes were differentially expressed in ticks, whereas only 99 genes responded during recovery to direct cold shock. Recovery from RCH resulted in an upregulation of various pathways associated with ion binding, transport, metabolism and cellular structures seen in the response of other arthropods to cold. The accumulation of various metabolites, including several amino acids and betaine, corresponded to transcriptional shifts in the pathways associated with these molecules, suggesting congruent metabolome and transcriptome changes. Ticks, D. variabilis and Amblyomma maculatum, receiving exogenous betaine and valine demonstrated enhanced cold tolerance, suggesting cryoprotective effects of these metabolites. Overall, many of the responses during recovery from cold shock in ticks were similar to those observed in other arthropods, but several adjustments may be distinct from the responses in other currently examined taxa.

A Dual-Site Inhibitor of CBP/p300 KIX is a Selective and Effective Modulator of Myb.

The protein-protein interaction between the KIX motif of the transcriptional coactivator CBP/p300 and the transcriptional activator Myb is a high-value target due to its established role in certain acute myeloid leukemias (AML) and potential contributions to other cancers. However, the CBP/p300 KIX domain has multiple binding sites, several structural homologues, many binding partners, and substantial conformational plasticity, making it challenging to specifically target using small-molecule inhibitors. Here, we report a picomolar dual-site inhibitor (MybLL-tide) of the Myb-CBP/p300 KIX interaction. MybLL-tide has higher affinity for CBP/p300 KIX than any previously reported compounds while also possessing 5600-fold selectivity for the CBP/p300 KIX domain over other coactivator domains. MybLL-tide blocks the association of CBP and p300 with Myb in the context of the proteome, leading to inhibition of key Myb·KIX-dependent genes in AML cells. These results show that MybLL-tide is an effective, modifiable tool to selectively target the KIX domain and assess transcriptional effects in AML cells and potentially other cancers featuring aberrant Myb behavior. Additionally, the dual-site design has applicability to the other challenging coactivators that bear multiple binding surfaces.

Advancing frost dates have reduced frost risk among most North American angiosperms since 1980.

In recent decades, the final frost dates of winter have advanced throughout North America, and many angiosperm taxa have simultaneously advanced their flowering times as the climate has warmed. Phenological advancement may reduce plant fitness, as flowering prior to the final frost date of the winter/spring transition may damage flower buds or open flowers, limiting fruit and seed production. The risk of floral exposure to frost in the recent past and in the future, however, also depends on whether the last day of winter frost is advancing more rapidly, or less rapidly, than the date of onset of flowering in response to climate warming. This study presents the first continental-scale assessment of recent changes in frost risk to floral tissues, using digital records of 475,694 herbarium specimens representing 1,653 angiosperm species collected across North America from 1920 to 2015. For most species, among sites from which they have been collected, dates of last frost have advanced much more rapidly than flowering dates. As a result, frost risk has declined in 66% of sampled species. Moreover, exotic species consistently exhibit lower frost risk than native species, primarily because the former occupy warmer habitats where the annual frost-free period begins earlier. While reducing the probability of exposure to frost has clear benefits for the survival of flower buds and flowers, such phenological advancement may disrupt other ecological processes across North America, including pollination, herbivory, and disease transmission.

Trends and Burden of Hepatitis B Viral Infection in Children and Adults in a Tertiary Health Facility in North East Nigeria Over a Fifteen-year Period.

BACKGROUND: Hepatitis B infection is endemic in Nigeria where greater than six percent of the general population are chronic carriers. Transmission predominantly occurs in infants and children when compared with adults. Viral hepatitis deaths are mostly due to chronic liver disease. Routine immunization against hepatitis B virus infection in Nigeria is still low. AIMS: We planned to describe the burden and trend of hepatitis B viral infection at Federal Teaching Hospital, Gombe. METHODOLOGY: This study was a retrospective cross-sectional descriptive study. The results of all hepatitis B surface antigen (HBsAg) tests using rapid chromatographic immunoassay performed at the Federal Teaching Hospital, Gombe (FTHG), Nigeria from January 2000 to December 2014 were retrieved and analyzed. RESULTS: Between 2000 and 2014, 23,611 individuals ranging from 2 months to 98 years of age were tested for HBsAg. A total of 13,136 (55.6%) were males and 10,475 (44.4%) were females. Among individuals tested for hepatitis B surface antigen, 18.9% (4,456) were positive. A total of 70.6% (3,147) were males and 29.4% (11,239) were females. Male sex was significantly associated with HBsAg positivity (P < 0.001). The mean HBsAg prevalence over the 15-year periods among males and females were 22% and 12%, respectively (P < 0.001). The mean yearly HBV prevalence was 17.5%, 17.2%, 19.6%, 15.5%, and 4.4% among age-groups 0-18 years, 19-25 years, 26-45 years, 56-65 years, and >65 years, respectively (P = 0.132). The proportion of HBsAg-positive individuals was highest in the year 2012 (28.7%) and lowest in 2014 (1.8%). CONCLUSION: There was an increasing trend in HBV testing and diagnosis in children and adults in our facility over the last 15 years. Health facility capacity for HBV treatment and care requires strengthening.

Capture and Release of Protein-Nanoparticle Conjugates by Reversible Covalent Molecular Linkers.

A hybrid approach to covalently detachable molecules for nanoparticle capture and release from several custom-functionalized surfaces is described. This new surface chemistry capability provides a means for reversible binding of functionalized nanoparticles without relying on costly nucleic acid-based complexation. A new surface linker motif was devised wherein custom molecules were synthesized with components for surface anchoring, cleavage, and target capture through biotin-streptavidin binding. All capture-and-release chemistry is performed using physiological conditions (aqueous, pH 7). Covalent cleavage of linker molecules was achieved through incorporation of a tunable orthogonal reversible covalent (TORC) hydrazone functional group which underwent exchange with a competitive hydrazide aided by an aniline catalyst. The influence of the linker architecture on hydrazone exchange and nanoparticle release was probed by altering the distance between hydrazone and biotin groups using different length PEG spacers. Cleavable linkers were used to functionalize microwells, magnetic separation beads, and gold-coated glass surfaces. Upon functionalization, all surface types bound streptavidin and conjugated nanoparticles regardless of the linker structure. Conversely, the extent of hydrazone exchange as well as release of nanoparticles were influenced both by the hydrazone surface density and the linker molecular structure.

The health care cost of palliative care for cancer patients: a systematic review.

OBJECTIVES: Several delivery models of palliative care are currently available: hospital-based, outpatient-based, home-based, nursing home-based, and hospice-based. Weighing the differences in costs of these delivery models helps to advise on the future direction of expanding palliative care services. The objective of this review is to identify and summarize the best available evidence in the US on cost associated with palliative care for patients diagnosed with cancer. METHODS: The systematic review was carried out of studies conducted in the US between 2008 and 2018, searching PubMed, Medline, the Cochrane library, CINAHL, EconLit, the Social Science Citation Index, Embase, and Science Citation Index, using the following terms: palliative, cancer, carcinoma, cost, and reimbursement. RESULTS: The initial search identified 748 articles, of which 16 met the inclusion criteria. Eight studies (50%) were inpatient-based, four (25%) were combined outpatient/inpatient, two (12.5%) reported only on home-based palliative services, and two (12.5%) were in multiple settings. Most included studies showed that palliative care reduced the cost of health care by $1285-$20,719 for inpatient palliative care, $1000-$5198 for outpatient and inpatient combined, $4258 for home-based, and $117-$400 per day for home/hospice, combined outpatient/inpatient palliative care. CONCLUSION: Receiving palliative care after a cancer diagnosis was associated with lower costs for cancer patients, and remarkable differences exist in cost saving across different palliative care models.

Conformational Preference of Macrocycles Investigated by Ion-Mobility Mass Spectrometry and Distance Geometry Modeling.

Macrocycles provide intricate shape manifolds that leverage the depth of the modern organic chemistry toolbox. Novel chemistry can be introduced via new bond types and unique torsional angles inaccessible by traditional small molecules and biomolecules. In this work, we investigate the conformational space of a class of biscationic macrocycles in protic and aprotic solvents using a combination of ion-mobility spectrometry mass spectrometry, distance geometry modeling, and quantum mechanical calculations. We identify at least three major conformations of the macrocycles. Two of the conformations are rotational isomers in which the amide (carbonyl amide) N-C bond of the acyl hydrazine can adopt either E- or Z-configuration. The E- and Z-rotational isomers were separately observed in previous X-ray crystallography studies on the same set of macrocycles, but both isomers were never proved to exist for the same molecule. We show that low-dielectric solvents and counterions, such as Cl- or PF6-, appear to stabilize the Z-conformation. Lastly, desolvation of the macrocycles in the absence of bound counterions yields a gas-phase "flat" Z-conformation. Our results suggest that the macrocycles are flexible and behave much like short polypeptides. The combination of ion-mobility spectrometry mass spectrometry and distance geometry modeling provides a versatile and robust approach to unravel fundamental information on the flexible chemical space of macrocycles.

Examining therapist effects in relation to clients' race-ethnicity and gender: An intersectionality approach.

Women and Men of Color experience racism in unique and complex ways, just as White Women and Women of Color experience unique forms of sexism (i.e., gendered racism). Traditional analyses of therapists' cultural competence, broadly defined, have yet to examine the effect of intersectionality on the processes and outcomes of psychotherapy. Although previous research suggests that therapists differ in their effectiveness with Racial-Ethnic Minority (REM) clients, no study has examined therapist effects in terms of the intersectionality of clients' race-ethnicity and gender. This study applied an intersectionality framework to test therapist effects due to clients' race-ethnicity and gender. Data for this study consisted of 415 clients treated by 16 therapists. Results indicated that therapists differed in their ability to produce changes in symptom-defined psychological distress as a function of clients' intersecting identities of race-ethnicity and gender. Clinical implications and future research are discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Overlooked climate parameters best predict flowering onset: Assessing phenological models using the elastic net.

Determining the manner in which plant species shift their flowering times in response to climatic conditions is essential to understanding and forecasting the impacts of climate change on the world's flora. The limited taxonomic diversity and duration of most phenological datasets, however, have impeded a comprehensive, systematic determination of the best predictors of flowering phenology. Additionally, many studies of the relationship between climate conditions and plant phenology have included only a limited set of climate parameters that are often chosen a priori and may therefore overlook those parameters to which plants are most phenologically sensitive. This study harnesses 894,392 digital herbarium records and 1,959 in situ observations to produce the first assessment of the effects of a large number (25) of climate parameters on the flowering time of a very large number (2,468) of angiosperm taxa throughout North America. In addition, we compare the predictive capacity of phenological models constructed from the collection dates of herbarium specimens vs. repeated in situ observations of individual plants using a regression approach-elastic net regularization-that has not previously been used in phenological modeling, but exhibits several advantages over ordinary least squares and stepwise regression. When herbarium-derived data and in situ phenological observations were used to predict flowering onset, the multivariate models based on each of these data sources had similar predictive capacity (R2  = 0.27). Further, apart from mean maximum temperature (TMAX), the two best predictors of flowering time have not commonly been included in phenological models: the number of frost-free days (NFFD) and the quantity of precipitation as snow (PAS) in the seasons preceding flowering. By vetting these models across an unprecedented number of taxa, this work demonstrates a new approach to phenological modeling.

Retrospective Analysis of Physician-based Surveys Published in OPRS.

PURPOSE: To review physician-based clinical surveys published in Ophthalmic Plastic and Reconstructive Surgery. METHODS: Complementary Ovid and PubMed searches of Ophthalmic Plastic and Reconstructive Surgery journal content were performed for the term "survey." Results were narrowed to studies that specifically addressed physicians' clinical practices. This search resulted in 162 articles, and after dual-investigator independent screening, 13 surveys met inclusion criteria. RESULTS: Of the 13 surveys published from 2007 to January 2017, 6 were published since 2015, showing an increased trend in survey-based publications. Topics included assessing practice patterns regarding eyelid disorders, thyroid eye disease, optic nerve sheath fenestration, anophthalmic socket, and diagnosing lacrimal disorders. Average response rate was 38.7% (range 17.5-60%), with 201 average number of replies (range 72-310). Nine out of 13 surveys included some form of statistical analysis with the remainder presenting data in percentages. CONCLUSIONS: There has been an increased rate of survey-type publications in Ophthalmic Plastic and Reconstructive Surgery over the past 10 years. The low response rate and frequent lack of statistical analysis raise concerns regarding the validity and usefulness of such studies. The authors believe that survey studies can be improved through better standardization and the use of author guidelines. They have made specific recommendations to improve the impact of survey papers in the future.