Protocol to evaluate the antiviral effect of FDA-approved drugs against dengue virus in Huh7 cells and AG129 mice.

Finding an effective therapy against diseases caused by flaviviruses remains a challenge. Here, we present a protocol to test Food and Drug Administration-approved drugs that inhibit host nuclear protein import, promoting a reduction of dengue infection. We describe steps for analyzing the drug effect on nuclear import inhibition of cellular and viral proteins by confocal microscopy or western blotting. We then describe procedures for measuring the antiviral drug effects on virus-infected cells by flow cytometry and testing drug efficacy in dengue-infected AG129 mice by survival assays. For complete details on the use and execution of this protocol, please refer to Palacios-Rápalo et al.1.

Comparing binary & ordinal definitions of urinary & stool continence outcomes: Data from the National Spina Bifida Patient Registry.

INTRODUCTION: The National Spina Bifida Patient Registry (NSBPR) assesses bladder and bowel incontinence using ordinal categories, but prior NSBPR analyses employed binary classification. Our aims were to 1) perform the first NSBPR analysis of bladder and bowel incontinence as ordinal outcomes to compare to the binary definition and subject variables; 2) explore the correlation of incontinence with undergarment usage, and 3) assess incontinence status following continence surgeries. METHODS: Data from NSBPR participants' most recent clinic visit from 2013 to 2020 were analyzed. Ordinal categories of incontinence were compared to previously used binary definitions. Incontinence surgical outcomes were analyzed for those with data at least three months post-operatively. Chi-square tests evaluated associations among categorical variables. Univariate and ordinal logistic regression models were used to test associations of ordinal incontinence status with patient and condition factors. Statistical tests were 2-sided; p values < 0.05 were considered significant. RESULTS: Analysis of 7217 individuals using ordinal incontinence outcomes showed little difference from previously used binary outcomes. The final multivariable logistic regression models with ordinal multinomial outcomes showed that associations of incontinence with age, sex, race/ethnicity, health insurance, level of lesion, and continence management technique were similar to prior studies. Among those reporting never being incontinent of both bladder and bowel, 14% reported using protective undergarments. Of the 500 individuals who had bladder outlet surgery, 38% reported never being incontinent of urine. Of 1416 individuals who had appendicostomy (ACE) bowel surgery, 48% reported never being incontinent of stool. DISCUSSION: Our current analysis showed that ordinal continence outcome classification had similar continence findings as previous studies using the binary definition of continence. Expanding the binary definition of continence to include monthly episodes of incontinence did not greatly increase the proportion of continent individuals and, therefore, would have not likely made meaningful differences in continence outcomes in prior NSBPR analyses. However, it is known that even mild incontinence can affect quality of life, therefore, capturing any level of incontiennce is of clinical importance. Confirmation of the association of continence outcomes with sociodemographic, condition-related, and interventional factors with both approaches further validates previous analyses using the binary definition of continence. CONCLUSION: The previously used binary definition of bladder and bowel continence appears robust. Undergarment choice was a poor surrogate for reported incontinence. After bladder and bowel continence surgeries, 38% and 48%, respectively, reported never being incontinent.

Causes of death among people with myelomeningocele: A multi-institutional 47-year retrospective study.

PURPOSE: This study aimed to analyze organ system-based causes and non-organ system-based mechanisms of death (COD, MOD) in people with myelomeningocele (MMC), comparing urological to other COD. METHODS: A retrospective review was performed of 16 institutions in Canada/United States of non-random convenience sample of people with MMC (born > = 1972) using non-parametric statistics. RESULTS: Of 293 deaths (89% shunted hydrocephalus), 12% occurred in infancy, 35% in childhood, and 53% in adulthood (documented COD: 74%). For 261 shunted individuals, leading COD were neurological (21%) and pulmonary (17%), and leading MOD were infections (34%, including shunt infections: 4%) and non-infectious shunt malfunctions (14%). For 32 unshunted individuals, leading COD were pulmonary (34%) and cardiovascular (13%), and leading MOD were infections (38%) and non-infectious pulmonary (16%). COD and MOD varied by shunt status and age (p < = 0.04), not ambulation or birthyear (p > = 0.16). Urology-related deaths (urosepsis, renal failure, hematuria, bladder perforation/cancer: 10%) were more likely in females (p = 0.01), independent of age, shunt, or ambulatory status (p > = 0.40). COD/MOD were independent of bladder augmentation (p = >0.11). Unexplained deaths while asleep (4%) were independent of age, shunt status, and epilepsy (p >= 0.47). CONCLUSION: COD varied by shunt status. Leading MOD were infectious. Urology-related deaths (10%) were independent of shunt status; 26% of COD were unknown. Life-long multidisciplinary care and accurate mortality documentation are needed.

Spina Bifida Global Learning Collaborative: Educating the next generation of clinicians, researchers, and advocates.

PURPOSE: This project aimed to launch an international learning community to guide the development of a spina bifida (SB) curriculum for global health trainees. METHODS: Using a descriptive study design, a convenience sample of SB curricula were identified in 2022-23 by members of the Spina Bifida World Congress Outreach Committee and evaluated during a series of monthly Zoom calls to discuss SB education in a global health context. Participants included (1) leadership from the ReachAnother Foundation, (2) invited panelists from the Spina Bifida World Congress Global Health Symposium, and (3) global health students and preceptors. Education initiatives in Ethiopia, Sweden, Argentina, Ecuador, and the United States were evaluated vis-à-vis format and content. RESULTS: All of the education initiatives referenced the framework of the World Health Organization International Classification of Functioning, Disability and Health. Formats varied and included both virtual and interactive workshops, print materials, videos, and guides for small group discussion. Content addressed four domains: Folate Prevention, Neurosurgical Training, After Care, and Data Collection. A multidisciplinary approach, partnerships with families, and workforce pipeline training were identified as guiding themes for educating the next generation of SB researchers and clinicians in global health settings. CONCLUSION: The Spina Bifida Global Learning Collaborative is a transnational group of advocates, clinicians, and investigators whose mission is the advancement of SB-related global health education. Lessons learned from the collaborative are being leveraged to develop a global health curriculum for learners, which may improve services for individuals with SB around the globe.

From prenatal care to spina bifida related mortality: The lifespan is marked by transitions experienced by increasing immigrant and international populations.

Whether it is for collaboration on folic acid fortification or the standardization of care efforts concerning neurogenic bowel dysfunction, a global forum on neural tube defects related issues is needed. Propitiously, the 2023 Spina Bifida World Congress sponsored by the Spina Bifida Association (SBA) was a catalyst for transnational dialog in the field of spina bifida (SB) research. Concurrently, the Journal of Pediatric Rehabilitation Medicine (JPRM) provides a platform for both international research as well as numerous clinical and educational projects, such as The Lifespan Bowel Management Protocol, and social interventions taught through the American Academy of Pediatrics' Spina Bifida Transition ECHO. Through this open access issue, work by colleagues in Ethiopia, the Nordic countries, and Switzerland, as well as among other transnational populations is highlighted. The development of the Spina Bifida Global Learning Collaborative is also showcased, representing a training initiative across four continents. Correspondingly in this issue, JPRM published an update to the Transition Guidelines for the Care of People with Spina Bifida. The clinical guidelines are a product of the SBA Collaborative Care Network cooperative agreement with the National Center on Birth Defects and Developmental Disabilities in the Centers for Disease Control and Prevention. While colleagues across the globe remain committed to native, immigrant, and displaced populations of individuals affected by SB, JPRM will continue to distribute premier research in multidisciplinary care, education, and advocacy.

Addressing social determinants of health through customization: Quality improvement, telemedicine, and care coordination to serve immigrant families.

PURPOSE: The purpose of this project was to establish a pathway for electronic medical record (EMR) customization, utilizing quality improvement methodology, to both identify and address adverse social determinants of health (SDOH) among a diverse spina bifida (SB) population. METHODS: Starting in September 2020, the four fundamental steps were to (1) facilitate an advisory committee to safeguard the standard clinical protocols, (2) characterize barriers to implementation, (3) evaluate workflow to sustain data entry capture, and (4) manage the technology platform for seamless integration. The SB clinic was the first clinic within the enterprise to rollout the use of an adverse SDOH mitigation activity. A Spanish-speaking interpreter was scheduled for all clinics, as many families were limited in English proficiency. RESULTS: The customization of the EMR to support an efficient workflow to address SDOH was feasible in a large and diverse urban medical center. Of the 758 patients served in the clinic, a myelomeningocele diagnosis was present in 86% of individuals. While 52% of participants were female, ethnically 52% of individuals served were Latino. Many of these individuals disclosed being recent immigrants to the United States. Often immigration and asylum related issues were at the forefront of the SDOH issues addressed. CONCLUSION: Given the occurrence of adverse SDOH among individuals with SB, many of whom are new Latin-American immigrants, meaningful clinical efforts are needed to both identify and address the causes of the observed disparities. EMR customization is feasible and can identify and, through social prescriptions, address SDOH to support the provision of safe, high quality, and equitable care for vulnerable and medically complex populations at home and potentially abroad.

Lack of racial and ethnic diversity in lung cancer cell lines contributes to lung cancer health disparities.

Lung cancer is the leading cause of cancer death in the United States and worldwide, and a major source of cancer health disparities. Lung cancer cell lines provide key in vitro models for molecular studies of lung cancer development and progression, and for pre-clinical drug testing. To ensure health equity, it is imperative that cell lines representing different lung cancer histological types, carrying different cancer driver genes, and representing different genders, races, and ethnicities should be available. This is particularly relevant for cell lines from Black men, who experience the highest lung cancer mortality in the United States. Here, we undertook a review of the available lung cancer cell lines and their racial and ethnic origin. We noted a marked imbalance in the availability of cell lines from different races and ethnicities. Cell lines from Black patients were strongly underrepresented, and we identified no cell lines from Hispanic/Latin(x) (H/L), American Indian/American Native (AI/AN), or Native Hawaiian or other Pacific Islander (NHOPI) patients. The majority of cell lines were derived from White and Asian patients. Also missing are cell lines representing the cells-of-origin of the major lung cancer histological types, which can be used to model lung cancer development and to study the effects of environmental exposures on lung tissues. To our knowledge, the few available immortalized alveolar epithelial cell lines are all derived from White subjects, and the race and ethnicity of a handful of cell lines derived from bronchial epithelial cells are unknown. The lack of an appropriately diverse collection of lung cancer cell lines and lung cancer cell-of-origin lines severely limits racially and ethnically inclusive lung cancer research. It impedes the ability to develop inclusive models, screen comprehensively for effective compounds, pre-clinically test new drugs, and optimize precision medicine. It thereby hinders the development of therapies that can increase the survival of minority and underserved patients. The noted lack of cell lines from underrepresented groups should constitute a call to action to establish additional cell lines and ensure adequate representation of all population groups in this critical pre-clinical research resource.

Alveolar type I cells can give rise to KRAS-induced lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is the most prevalent subtype of lung cancer and presents clinically with a high degree of biological heterogeneity and distinct clinical outcomes. The current paradigm of LUAD etiology posits alveolar epithelial type II (AT2) cells as the primary cell of origin, while the role of AT1 cells in LUAD oncogenesis remains unknown. Here, we examine oncogenic transformation in mouse Gram-domain containing 2 (Gramd2)+ AT1 cells via oncogenic KRASG12D. Activation of KRASG12D in AT1 cells induces multifocal LUAD, primarily of papillary histology. Furthermore, KRT8+ intermediate cell states were observed in both AT2- and AT1-derived LUAD, but SCGB3A2+, another intermediate cell marker, was primarily associated with AT1 cells, suggesting different mechanisms of tumor evolution. Collectively, our study reveals that Gramd2+ AT1 cells can serve as a cell of origin for LUAD and suggests that distinct subtypes of LUAD based on cell of origin be considered in the development of therapeutics.

Age-Specific Probability of 4 Major Health Outcomes in Children with Spina Bifida.

OBJECTIVE: This study aimed to estimate the age-specific probability of 4 health outcomes in a large registry of individuals with spina bifida (SB). METHODS: The association between age and 4 health outcomes was examined in individuals with myelomeningocele (MMC, n = 5627) and non-myelomeningocele (NMMC, n = 1442) from the National Spina Bifida Patient Registry. Sixteen age categories were created, 1 for each year between the ages of 5 and 19 years and 1 for those aged 20 years or older. Generalized linear models were used to calculate the adjusted probability and 95% prediction intervals of each outcome for each age category, adjusting for sex and race/ethnicity. RESULTS: For the MMC and NMMC groups, the adjusted coefficients for the correlation between age and the probability of each outcome were -0.933 and -0.657 for bladder incontinence, -0.922 and -0.773 for bowel incontinence, 0.942 and 0.382 for skin breakdown, and 0.809 and 0.619 for lack of ambulation, respectively. CONCLUSION: In individuals with SB, age is inversely associated with the probability of bladder and bowel incontinence and directly associated with the probability of skin breakdown and lack of ambulation. The estimated age-specific probabilities of each outcome can help SB clinicians estimate the expected proportion of patients with the outcome at specific ages and explain the probability of the occurrence of these outcomes to patients and their families.

GRAMD2 + alveolar type I cell plasticity facilitates cell state transitions in organoid culture.

Alveolar epithelial regeneration is critical for normal lung function and becomes dysregulated in disease. While alveolar type 2 (AT2) and club cells are known distal lung epithelial progenitors, determining if alveolar epithelial type 1 (AT1) cells also contribute to alveolar regeneration has been hampered by lack of highly specific mouse models labeling AT1 cells. To address this, the Gramd2 CreERT2 transgenic strain was generated and crossed to Rosa mTmG mice. Extensive cellular characterization, including distal lung immunofluorescence and cytospin staining, confirmed that GRAMD2 + AT1 cells are highly enriched for green fluorescent protein (GFP). Interestingly, Gramd2 CreERT2 GFP + cells were able to form organoids in organoid co-culture with Mlg fibroblasts. Temporal scRNAseq revealed that Gramd2 + AT1 cells transition through numerous intermediate lung epithelial cell states including basal, secretory and AT2 cell in organoids while acquiring proliferative capacity. Our results indicate that Gramd2 + AT1 cells are highly plastic suggesting they may contribute to alveolar regeneration.

The impact of a health care transition clinic on spina bifida condition management and transition planning.

BACKGROUND: To better serve the growing population of individuals with spina bifida (SB) living into adulthood, pediatric SB clinics have developed structured health care transition (HCT) supports for adolescents and young adults. Evaluating the impact of structured HCT on SB-related chronic condition outcomes and transition planning goals is needed to assess such interventions. OBJECTIVE: This study explored the impact of a SB HCT Clinic on SB-related chronic condition management outcomes (e.g., reported bowel and bladder regimens and presence of pressure injury) and transition planning goals (e.g., decision-making, insurance, and transportation). METHODS: A retrospective chart review was conducted of young adults with SB who did and did not participate in an SB HCT Clinic before establishing an adult clinic to compare SB-condition outcomes and HCT planning goals between groups. Associations between demographic and clinical variables and outcomes were also assessed. RESULTS: The HCT group (n = 68) was more likely to use a bowel regimen (P < 0.01) compared to the non-HCT group (n = 94). There were no differences regarding bladder regimens or incidence of pressure injuries. For HCT planning, the groups differed regarding decision-making supports (P = 0.01). Additionally, the HCT group was more likely to use self-transportation (P = 0.01) or Medicaid transportation (P < 0.01). CONCLUSION: This single-center HCT program improved the use of a bowel regimen at the time of transfer to adult care and impacted HCT planning regarding decision-making and transportation. These initial findings support the need for further development and assessment of HCT programs for this population.

International collaborations on advocacy, education, and research: Broad-spectrum thematic diversity catalyzes multidisciplinary spina bifida care.

As with the wide range in spina bifida (SB) incidence rates across nations, there is also wide variance in topics encountered by clinicians today. Both the wide variance in SB incidence rates and the wide diversity of topics to be addressed provide the backdrop for any dialogue among professionals serving this population. On the international stage, the World Congress on Spina Bifida Research and Care has been the only conference dedicated solely to research, practical challenges, and real-life solutions for those living with SB, their families, and caregivers. As a conference with a clear sense of the growing global village, the 2023 congress showcased innovative research from junior to preeminent investigators. Topical areas included urology, neurosurgery, global health, prenatal surgery, and transition to adult care amid others. Ultimately, through the dissemination of a compendium of conference abstracts, we hope that professionals will be aided and inspired to continue to improve the education, advocacy, and care among the many communities of individuals affected by SB globally.

Environmental selection, rather than neutral processes, best explain regional patterns of diversity in a tropical rainforest fish.

To conserve the high functional and genetic variation in hotspots such as tropical rainforests, it is essential to understand the forces driving and maintaining biodiversity. We asked to what extent environmental gradients and terrain structure affect morphological and genomic variation across the wet tropical distribution of an Australian rainbowfish, Melanotaenia splendida splendida. We used an integrative riverscape genomics and morphometrics framework to assess the influence of these factors on both putative adaptive and non-adaptive spatial divergence. We found that neutral genetic population structure was largely explainable by restricted gene flow among drainages. However, environmental associations revealed that ecological variables had a similar power to explain overall genetic variation, and greater power to explain body shape variation, than the included neutral covariables. Hydrological and thermal variables were the strongest environmental predictors and were correlated with traits previously linked to heritable habitat-associated dimorphism in rainbowfishes. In addition, climate-associated genetic variation was significantly associated with morphology, supporting heritability of shape variation. These results support the inference of evolved functional differences among localities, and the importance of hydroclimate in early stages of diversification. We expect that substantial evolutionary responses will be required in tropical rainforest endemics to mitigate local fitness losses due to changing climates.

Protection of Boronic Acids Using a Tridentate Aminophenol ONO Ligand for Selective Suzuki-Miyaura Coupling.

Boronic acid protecting group chemistry powerfully enhances the versatility of Suzuki-Miyaura cross-coupling. Prominent examples include trifluoroborate salts, N-methyliminodiacetic acid (MIDA) boronates, and 1,8-diaminonaphthalene boronamides. In this work, we present a bis(2-hydroxybenzyl)methylamine (BOMA) ligand that forms tridentate complexes with boronic acids much like the MIDA ligand but the deprotection is facilitated by organic acids. The BOMA boronates showed considerable stability in both aqueous base and acid, and a variety of chemoselective reactions were performed on these boronates, including selective Suzuki-Miyaura coupling, palladium-catalyzed borylation, ester hydrolysis, alkylation, lithiation-borylation, and oxidative hydroxydeboronation.

Education and employment as young adults living with spina bifida transition to adulthood in the USA: A study of the National Spina Bifida Patient Registry.

AIM: To describe the education and employment transition experience of young adults with spina bifida (YASB) and investigate factors associated with employment. METHOD: We queried education and employment data from the US National Spina Bifida Patient Registry from 2009 to 2019. We applied generalized estimating equations models to analyze sociodemographic and disease-related factors associated with employment. RESULTS: A total of 1909 participants (850 males, 1059 females) aged 18 to 26 years contributed 4379 annual visits. Nearly 84% had myelomeningocele and, at last visit, the median age was 21 years (mean 21 years 5 months, SD 2 years 10 months). A total of 41.8% had at least some post-high school education, and 23.9% were employed. In a multivariable regression model, employment was significantly associated with education level, lower extremity functional level, bowel continence, insurance, and history of non-shunt surgery. This large, national sample of YASB demonstrated low rates of post-secondary education attainment and employment and several potentially modifiable factors associated with employment. INTERPRETATION: Specific sociodemographic, medical, and functional factors associated with employment are important for clinicians to consider when facilitating transition for YASB into adulthood. Additional research is needed to understand the impact of cognitive functioning and social determinants of health on transition success in YASB. WHAT THIS PAPER ADDS: There were low education attainment and employment rates in a large sample of young adults with spina bifida. Specific sociodemographic, medical, and functional factors are associated with employment. Some employment-associated factors, such as continence and self-management skills, are modifiable.

Neurodevelopmental Implications on Urological Self-management Among People Living With Spina Bifida: A Practical Guide for Urology Providers.

Although folic acid fortification and advances in prenatal repair have reduced Spina Bifida (SB) prevalence and the severity of comorbidities, individuals with SB remain at elevated risk for neurocognitive impairments that studies have shown can negatively impact, among other things, urological self-care. Identifying and addressing these impairments with practical interventions can meaningfully improve long-term outcomes for individuals with SB. We review neurocognitive impairments associated with SB and provide practical solutions to support improvement of long-term urological outcomes.

From autism to zoom®: Spina bifida advocacy, care, education, and research in a changing word.

Whereas legislation mandates for folic acid fortification have been implemented throughout many nations, divergent neural tube defects (NTDs) prevalence rates still remain among the world's populations. In North America, the prevalence estimate is 39 infants per 100,000 live births. Open spina bifida (SB), also known as myelomeningocele, remains the most complex congenital abnormality of the central nervous system compatible with long term survival; this recognized complexity gives rise to emerging comorbidities and interventions. For example, increasing autism spectrum disorder rates have been reported among individuals with SB utilizing a 31,220 subject population-based birth cohort. Along with new clinical observations, telecommunication platforms such as Zoom® have evolved as clinical and investigational tools. Historically, society meetings, research conferences, and journals have provided opportunities for professional development and dissemination of up-to-date materials. The Journal of Pediatric Rehabilitation Medicine (JPRM) has arisen as an open-access global platform for the dissemination of SB-related inquiry. The journal has also highlighted the research presented at the Spina Bifida Association's previous Spina Bifida World Congresses. At the last congress, which was held in 2017, twenty-three countries were represented; this number is expected to grow by the next convocation in 2023. This congress will provide an opportunity for health care professionals from around the globe to present a broad array of research topics and build collaborations. Concurrently, the JPRM will continue as an open-access platform for SB advocacy, care, education, and investigation, across our fast changing world for the international SB community well into the future.

Association between age of starting clean intermittent catheterization and current urinary continence in individuals with myelomeningocele.

INTRODUCTION: Patients with myelomeningocele often use clean intermittent catheterization (CIC) for renal preservation and to promote urinary continence. While starting CIC at an early age is associated with better renal outcomes, the impact of age of CIC initiation on continence outcomes has not been examined. OBJECTIVE: To examine whether earlier CIC initiation is associated with higher likelihood of current urinary continence for patients with myelomeningocele. STUDY DESIGN: Data of patients aged ≥5 years at last visit were obtained from 35 spina bifida clinics participating in the National Spina Bifida Patient Registry from 2013 to 2018. Sociodemographic characteristics, disease characteristics, and current bladder management strategies were collected. Via univariate and multiple logistic regression models, the latter conducted controlling for all variables associated with current continent status, associations between continence and sociodemographic factors, condition characteristics, and age CIC began (<3 years of age, 3-5 years, 6-11 years, ≥12 years) were analyzed. RESULTS: Data from 3510 individuals were included (mean age at last visit = 17.0 years, range 5.0-88.7). The sample was evenly distributed by sex (52% female); most individuals were non-Hispanic White (62.6%). The majority of patients (55.2%) started CIC before age 3 years. Continence varied markedly across those who never started CIC (0.6% of patients were continent) and those who started at any age (range 35.3-38.5%). Among those who started CIC, the magnitude of the association was not proportional to age CIC was started. Compared with those who started CIC at age 12 or older, estimated adjusted odds ratio of being continent ranged from 1.04 (6-11 years, 95% CI, 0.72-1.52) to 1.25 (<3 years, 95% CI, 0.89-1.76). DISCUSSION: Although CIC may be positively associated with achieving urinary continence in individuals with myelomeningocele, we could not demonstrate that younger age at CIC initiation increased the likelihood of achieving this goal. Limitations include lack of data on reason for starting CIC, urodynamic data, and the observational nature of data collection. CONCLUSIONS: Further study is needed addressing limitations of the current investigation to determine if urinary continence outcomes are influenced by the age of starting CIC among patients with myelomeningocele.

Synthesis, antitumor activity, 3D-QSAR and molecular docking studies of new iodinated 4-(3H)-quinazolinones 3N-substituted.

A novel series of 6-iodo-2-methylquinazolin-4-(3H)-one derivatives, 3a-n, were synthesized and evaluated for their in vitro cytotoxic activity. Compounds 3a, 3b, 3d, 3e, and 3h showed remarkable cytotoxic activity on specific human cancer cell lines when compared to the anti-cancer drug, paclitaxel. Compound 3a was found to be particularly effective on promyelocytic leukaemia HL60 and non-Hodgkin lymphoma U937, with IC50 values of 21 and 30 µM, respectively. Compound 3d showed significant activity against cervical cancer HeLa (IC50 = 10 µM). The compounds 3e and 3h were strongly active against glioblastoma multiform tumour T98G, with IC50 values of 12 and 22 µM, respectively. These five compounds showed an interesting cytotoxic activity on four human cancer cell types of high incidence. The molecular docking results reveal a good correlation between experimental activity and calculated binding affinity on dihydrofolate reductase (DHFR). Docking studies proved 3d as the most potent compound. In addition, the three-dimensional quantitative structure-activity relationship (3D-QSAR) analysis exhibited activities that may indicate the existence of electron-withdrawing and lipophilic groups at the para-position of the phenyl ring and hydrophobic interactions of the quinazolinic ring in the DHFR active site.

Spatial organization of rat's behavior in a situation with three optional lever-pressing responses under continuous and fixed-interval schedules of food.

We assessed spatiotemporal distribution of behavior as a function of the spatial and temporal arrangement of food delivery. Eight food-deprived rats were exposed in an extended experimental chamber to a continuous reinforcement schedule (CRf) or to a fixed interval (FI) 30 s, with three levers contiguous to food dispenser or placed on separate panels. Responses on any of the levers were equally operative on the ongoing schedule. All rats moved mainly near to dispenser and levers when these were contiguous, under both, CRf and FI schedules, although distribution of responses on different levers was more variant under FI than under CRf. With separate levers, rats traveled through a larger area of the experimental space, especially under FI. Distribution of responses showed more variation under FI than under CRf schedule. Under FI, response patterns consisted in a post-meal pause followed by an acceleration towards the next food. Findings are discussed in the context of studies in which have been reported inconsistent patterns under FI schedules when are manipulated the number of operanda, dispensers, and their locations. It is highlighted the relevance of continuous analysis of rats' displacement, to account for the configuration of response patterns observed in this study.