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1.
bioRxiv ; 2023 Dec 02.
Article in English | MEDLINE | ID: mdl-37662337

ABSTRACT

Epilepsy is the 4th most prevalent neurological disorder with over 50 million cases worldwide. While a number of drugs exist to suppress seizures, approximately 1/3 of patients remain drug resistant, and no current treatments are disease modifying. Using network and systems-based approaches, we find that the histone methylase EZH2 suppresses epileptogenesis and slows disease progression, via repression of JAK1 and STAT3 signaling in hippocampal neurons. Pharmacological inhibition of JAK1 with the orally available, FDA-approved drug CP690550 (Tofacitinib) profoundly suppresses behavioral and electrographic seizures after the onset of epilepsy across preclinical rodent models of acquired epilepsy. This seizure suppression persists for weeks after drug withdrawal. Identification of an endogenous protective response to status epilepticus in the form of EZH2 induction has highlighted a critical role for the JAK1 kinase and STAT3 in both the initiation and propagation of epilepsy across preclinical rodent models and human disease. Overall, we find that STAT3 is transiently activated after insult, reactivates with spontaneous seizures, and remains targetable for disease modification in chronic epilepsy.

2.
Front Neuroendocrinol ; 71: 101098, 2023 10.
Article in English | MEDLINE | ID: mdl-37619655

ABSTRACT

Cyclic variations in hormones during the normal menstrual cycle underlie multiple central nervous system (CNS)-linked disorders, including premenstrual mood disorder (PMD), menstrual migraine (MM), and catamenial epilepsy (CE). Despite this foundational mechanistic link, these three fields operate independently of each other. In this scoping review (N = 85 studies), we survey existing human research studies in PMD, MM, and CE to outline the exogenous experimental hormone manipulation trials conducted in these fields. We examine a broad range of literature across these disorders in order to summarize existing diagnostic practices and research methods, highlight gaps in the experimental human literature, and elucidate future research opportunities within each field. While no individual treatment or study design can fit every disease, there is immense overlap in study design and established neuroendocrine-based hormone sensitivity among the menstrual cycle-related disorders PMD, MM, and CE. SCOPING REVIEW STRUCTURED SUMMARY: Background. The menstrual cycle can be a biological trigger of symptoms in certain brain disorders, leading to specific, menstrual cycle-linked phenomena such as premenstrual mood disorders (PMD), menstrual migraine (MM), and catamenial epilepsy (CE). Despite the overlap in chronicity and hormonal provocation, these fields have historically operated independently, without any systematic communication about methods or mechanisms. OBJECTIVE: Online databases were used to identify articles published between 1950 and 2021 that studied hormonal manipulations in reproductive-aged females with either PMD, MM, or CE. We selected N = 85 studies that met the following criteria: 1) included a study population of females with natural menstrual cycles (e.g., not perimenopausal, pregnant, or using hormonal medications that were not the primary study variable); 2) involved an exogenous hormone manipulation; 3) involved a repeated measurement across at least two cycle phases as the primary outcome variable. CHARTING METHODS: After exporting online database query results, authors extracted sample size, clinical diagnosis of sample population, study design, experimental hormone manipulation, cyclical outcome measure, and results from each trial. Charting was completed manually, with two authors reviewing each trial. RESULTS: Exogenous hormone manipulations have been tested as treatment options for PMD (N = 56 trials) more frequently than MM (N = 21) or CE (N = 8). Combined oral contraceptive (COC) trials, specifically those containing drospirenone as the progestin, are a well-studied area with promising results for treating both PMDD and MM. We found no trials of COCs in CE. Many trials test ovulation suppression using gonadotropin-releasing hormone agonists (GnRHa), and a meta-analysis supports their efficacy in PMD; GnRHa have been tested in two MM-related trials, and one CE open-label case series. Finally, we found that non-contraceptive hormone manipulations, including but not limited to short-term transdermal estradiol, progesterone supplementation, and progesterone antagonism, have been used across all three disorders. CONCLUSIONS: Research in PMD, MM, and CE commonly have overlapping study design and research methods, and similar effects of some interventions suggest the possibility of overlapping mechanisms contributing to their cyclical symptom presentation. Our scoping review is the first to summarize existing clinical trials in these three brain disorders, specifically focusing on hormonal treatment trials. We find that PMD has a stronger body of literature for ovulation-suppressing COC and GnRHa trials; the field of MM consists of extensive estrogen-based studies; and current consensus in CE focuses on progesterone supplementation during the luteal phase, with limited estrogen manipulations due to concerns about seizure provocation. We argue that researchers in any of these respective disciplines would benefit from greater communication regarding methods for assessment, diagnosis, subtyping, and experimental manipulation. With this scoping review, we hope to increase collaboration and communication among researchers to ultimately improve diagnosis and treatment for menstrual-cycle-linked brain disorders.


Subject(s)
Epilepsy , Migraine Disorders , Premenstrual Syndrome , Female , Humans , Pregnancy , Adult , Progesterone , Premenstrual Syndrome/drug therapy , Menstrual Cycle , Migraine Disorders/drug therapy , Estradiol/therapeutic use , Estrogens/therapeutic use , Mood Disorders/drug therapy , Mood Disorders/etiology
5.
Proc Natl Acad Sci U S A ; 119(12): e2116264119, 2022 03 22.
Article in English | MEDLINE | ID: mdl-35286202

ABSTRACT

SignificanceWe provide the first assessment of aboveground live tree biomass in a mixed conifer forest over the late Holocene. The biomass record, coupled with local Native oral history and fire scar records, shows that Native burning practices, along with a natural lightning-based fire regime, promoted long-term stability of the forest structure and composition for at least 1 millennium in a California forest. This record demonstrates that climate alone cannot account for observed forest conditions. Instead, forests were also shaped by a regime of frequent fire, including intentional ignitions by Native people. This work suggests a large-scale intervention could be required to achieve the historical conditions that supported forest resiliency and reflected Indigenous influence.


Subject(s)
Conservation of Natural Resources , Fires , California , Forests , Humans , Trees
6.
Chem Commun (Camb) ; 58(24): 3941-3944, 2022 Mar 22.
Article in English | MEDLINE | ID: mdl-35244630

ABSTRACT

Enantiomers of the low-molecular-weight gelator (LMWG) DBS-CONHNH2, based on D- or L- 1,3 : 2,4-dibenzylidenesorbitol (DBS), were synthesised. Enantiomeric gels are equivalent, but when mixtures of enantiomers are used, although gels still form, they are weaker than homochiral gels. Nanoscale chirality is lost on adding even a small proportion of the opposite enantiomer - homochiral assembly underpins effective gelation. Enantiomeric gels encapsulate the two enantiomers of anti-inflammatory drug naproxen, with thermal & mechanical differences between diastereomeric systems. We hence demonstrate the importance of chirality in DBS assembly and its interactions with chiral additives.


Subject(s)
Hydrogels , Stereoisomerism
7.
PNAS Nexus ; 1(3): pgac115, 2022 Jul.
Article in English | MEDLINE | ID: mdl-36741468

ABSTRACT

Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are a fundamental cause and consequence of global change, impacting people and the biophysical systems on which they depend. As part of the newly emerging Anthropocene, marked by human-caused climate change and radical changes to ecosystems, fire danger is increasing, and fires are having increasingly devastating impacts on human health, infrastructure, and ecosystem services. Increasing fire danger is a vexing problem that requires deep transdisciplinary, trans-sector, and inclusive partnerships to address. Here, we outline barriers and opportunities in the next generation of fire science and provide guidance for investment in future research. We synthesize insights needed to better address the long-standing challenges of innovation across disciplines to (i) promote coordinated research efforts; (ii) embrace different ways of knowing and knowledge generation; (iii) promote exploration of fundamental science; (iv) capitalize on the "firehose" of data for societal benefit; and (v) integrate human and natural systems into models across multiple scales. Fire science is thus at a critical transitional moment. We need to shift from observation and modeled representations of varying components of climate, people, vegetation, and fire to more integrative and predictive approaches that support pathways toward mitigating and adapting to our increasingly flammable world, including the utilization of fire for human safety and benefit. Only through overcoming institutional silos and accessing knowledge across diverse communities can we effectively undertake research that improves outcomes in our more fiery future.

8.
Chemistry ; 27(52): 13203-13210, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34346527

ABSTRACT

This article describes the fabrication of new pH-responsive hybrid gel beads combining the polymer gelator calcium alginate with two different low-molecular-weight gelators (LMWGs) based on 1,3 : 2,4-dibenzylidene-d-sorbitol: pH-responsive DBS-COOH and thermally responsive DBS-CONHNH2 , thus clearly demonstrating that different classes of LMWG can be fabricated into gel beads by using this approach. We also demonstrate that self-assembled multicomponent gel beads can be formed by using different combinations of these gelators. The different gel bead formulations exhibit different responsiveness - the DBS-COOH network can disassemble within those beads in which it is present upon raising the pH. To exemplify preliminary data for a potential application for these hybrid gel beads, we explored aspects of the delivery of the lipid-lowering active pharmaceutical ingredient (API) rosuvastatin. The release profile of this statin from the hybrid gel beads is pH-dependent, with greater release at pH 7.4 than at pH 4.0 - primary control of this process results from the pKa of the API. The extent of pH-mediated API release is also significantly further modified according to gel bead composition. The DBS-COOH/alginate beads show rapid, highly effective drug release at pH 7.4, whereas the three-component DBS-COOH/DBS-CONHNH2 /alginate system shows controlled slow release of the API under the same conditions. These initial results indicate that such gel beads constitute a promising, versatile and easily tuned platform suitable for further development for controlled drug-delivery applications.


Subject(s)
Alginates , Polymers , Drug Liberation , Gels , Hydrogen-Ion Concentration , Rosuvastatin Calcium
9.
Adv Sci (Weinh) ; 8(14): e2101058, 2021 07.
Article in English | MEDLINE | ID: mdl-34029010

ABSTRACT

This paper reports the use of a self-assembling hydrogel as a delivery vehicle for the Parkinson's disease drug l-DOPA. Based on a two-component combination of an l-glutamine amide derivative and benzaldehyde, this gel has very soft rheological properties and self-healing characteristics. It is demonstrated that the gel can be formulated to encapsulate l-DOPA. These drug-loaded gels are characterized, and rapid release of the drug is obtained from the gel network. This drug-loaded hydrogel has appropriate rheological characteristics to be amenable for injection. This system is therefore tested as a vehicle for nasal delivery of neurologically-active drugs-a drug delivery strategy that can potentially avoid first pass liver metabolism and bypass the blood-brain barrier, hence enhancing brain uptake. In vitro tests indicate that the gel has biocompatibility with respect to nasal epithelial cells. Furthermore, animal studies demonstrate that the nasal delivery of a gel loaded with 3 H-labeled l-DOPA out-performed a simple intranasal l-DOPA solution. This is attributed to longer residence times of the gel in the nasal cavity resulting in increased blood and brain concentrations. It is demonstrated that the likely routes of brain penetration of intranasally-delivered l-DOPA gel involve the trigeminal and olfactory nerves connecting to other brain regions.


Subject(s)
Antiparkinson Agents/administration & dosage , Drug Delivery Systems/methods , Hydrogels/administration & dosage , Levodopa/administration & dosage , Administration, Intranasal , Animals , Cell Line, Tumor , Disease Models, Animal , Female , Humans , Mice , Mice, Inbred BALB C , Nasal Mucosa/metabolism
10.
Mol Metab ; 53: 101258, 2021 11.
Article in English | MEDLINE | ID: mdl-34023483

ABSTRACT

OBJECTIVE: Acyl-ghrelin regulates eating, body weight, blood glucose, and GH secretion upon binding to its receptor GHSR (growth hormone secretagogue receptor; ghrelin receptor). GHSR is distributed in several brain regions and some peripheral cell-types including pituitary somatotrophs. The objective of the current study was to determine the functional significance of acyl-ghrelin's action on GHSR-expressing somatotrophs in mediating GH secretion and several of acyl-ghrelin's metabolic actions. METHODS: GH-IRES-Cre mice and loxP-flanked (floxed) GHSR mice were newly developed and then crossed to one another to generate mice that lacked GHSR selectively from somatotrophs. Following validation of mice with somatotroph-selective GHSR deletion, metabolic responses of these mice and control littermates were assessed following both acute and chronic acyl-ghrelin administration, a 24-h fast, and a prolonged 60% chronic caloric restriction protocol modeling starvation. RESULTS: In mice with somatotroph-selective GHSR deletion, a single peripheral injection of acyl-ghrelin failed to induce GH secretion or increase food intake, unlike wild-type and other littermate control groups. However, the usual acute blood glucose increase in response to the acyl-ghrelin bolus was preserved. Similarly, chronic s.c. acyl-ghrelin administration to mice with somatotroph-selective GHSR deletion failed to increase plasma GH, food intake, or body weight. Physiologically elevating plasma acyl-ghrelin via a 24-h fast also failed to raise plasma GH and resulted in a limited hyperphagic response upon food reintroduction in mice with somatotroph-selective GHSR deletion, although those mice nonetheless did not exhibit an exaggerated reduction in blood glucose. Physiologically elevating plasma acyl-ghrelin via a 15-day caloric restriction protocol which provided only 40% of usual daily calories failed to raise plasma GH in mice with somatotroph-selective GHSR deletion, although those mice did not exhibit life-threatening hypoglycemia. CONCLUSIONS: These results reveal that direct engagement of GHSR-expressing somatotrophs is required for a peripheral ghrelin bolus to acutely stimulate GH secretion and the actions of chronic acyl-ghrelin delivery and physiological plasma acyl-ghrelin elevations to increase plasma GH. These results also suggest that actions of acyl-ghrelin to increase food intake and body weight are reliant on direct activation of GHSRs expressed on somatotrophs. Furthermore, these results suggest that the glucoregulatory actions of acyl-ghrelin - in particular, its actions to raise blood glucose when acutely administered, prevent small blood glucose drops following a 24-h fast, and avert life-threatening hypoglycemia during an acute-on-chronic caloric restriction protocol - do not depend on GHSR expression by somatotrophs.


Subject(s)
Ghrelin/metabolism , Growth Hormone/metabolism , Animals , Blood Glucose/metabolism , Ghrelin/analogs & derivatives , Mice , Receptors, Ghrelin/deficiency , Receptors, Ghrelin/genetics , Receptors, Ghrelin/metabolism
11.
Chem Commun (Camb) ; 56(75): 11046-11049, 2020 Sep 22.
Article in English | MEDLINE | ID: mdl-32810197

ABSTRACT

A hybrid gel has been developed by combining two supramolecular gelators. Each gelator endows the hybrid gel with its own characteristics. One gelator enables pH-mediated controlled release of the active pharmaceutical ingredient naproxen, while the other new gelator enhances mechanical stability. Self-assembly thus gives multi-functional gels with potential applications.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/chemistry , Hydrogels/chemistry , Naproxen/chemistry , Drug Liberation , Hydrogen-Ion Concentration , Macromolecular Substances/chemistry , Molecular Conformation , Particle Size , Surface Properties , Temperature
12.
J Am Chem Soc ; 142(9): 4379-4389, 2020 03 04.
Article in English | MEDLINE | ID: mdl-32023044

ABSTRACT

This paper reports an investigation into organocatalytic hydrogels as prebiotically relevant systems. Gels are interesting prebiotic reaction media, combining heterogeneous and homogeneous characteristics with a structurally organized active "solid-like" catalyst separated from the surrounding environment, yet in intimate contact with the solution phase and readily accessible via "liquid-like" diffusion. A simple self-assembling glutamine amide derivative 1 was initially found to catalyze a model aldol reaction between cyclohexanone and 4-nitrobenzaldehyde, but it did not maintain its gel structure during reaction. In this study, it was observed that compound 1 could react directly with the benzaldehyde to form a hydrogel in situ based on Schiff base 2 as a low-molecular-weight gelator (LMWG). This new dynamic gel is a rare example of a two-component self-assembled LMWG hydrogel and was fully characterized. It was demonstrated that glutamine amide 1 could select an optimal aldehyde component and preferentially assemble from mixtures. In the hunt for an organocatalyst, reductive conditions were applied to the Schiff base to yield secondary amine 3, which is also a highly effective hydrogelator at very low loadings with a high degree of nanoscale order. Most importantly, the hydrogel based on 3 catalyzed the prebiotically relevant aldol dimerization of glycolaldehyde to give threose and erythrose. In buffered conditions, this reaction gave excellent conversions, good diastereoselectivity, and some enantioselectivity. Catalysis using the hydrogel of 3 was much better than that using non-assembled 3-demonstrating a clear benefit of self-assembly. The results suggest that hydrogels offer a potential strategy by which prebiotic reactions can be promoted using simple, prebiotically plausible LMWGs that can selectively self-organize from complex mixtures. Such processes may have been of prebiotic importance.


Subject(s)
Glutamine/analogs & derivatives , Hydrogels/chemistry , Acetaldehyde/analogs & derivatives , Acetaldehyde/chemistry , Benzaldehydes/chemistry , Catalysis , Cyclohexanones/chemistry , Schiff Bases/chemical synthesis , Stereoisomerism , Tetroses/chemical synthesis
13.
J Surg Res ; 153(1): 152-5, 2009 May 01.
Article in English | MEDLINE | ID: mdl-18674785

ABSTRACT

BACKGROUND: The most common 3rd-year surgery clerkship uses general surgery services while limiting the involvement of subspecialty services. A novel surgery clerkship in which students were assigned to either general surgery or subspecialty services for the entire clerkship was tried at a large Midwestern medical school. The purpose of this study was to investigate the outcomes of clerks from subspecialty services and compare them with clerks from general surgery services. METHODS: Outcome measures included scores on the National Board of Medical Examiners Surgery Content Examination, faculty evaluation scores, and residency match results. A multivariate analysis of covariance compared National Board of Medical Examiners test scores and faculty evaluation ratings across service groups. United States Medical Licensing Examination Step 1 scores served as a covariate. RESULTS: Results showed significant differences between groups on faculty evaluation scores (F = 28.03; P

Subject(s)
Clinical Clerkship/organization & administration , Education, Medical, Undergraduate/organization & administration , Program Evaluation , Specialties, Surgical/education , Achievement , Clinical Competence , Curriculum , Educational Measurement , General Surgery/education , Humans , Internship and Residency , Students, Medical , United States
14.
Am J Surg ; 189(2): 129-33, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15720978

ABSTRACT

BACKGROUND: This study was conducted to determine if a surgical career became more appealing to medical students with the resident work week limited to 80 hours. METHODS: At the start and conclusion of each surgery clerkship rotation, students completed a survey addressing perception of surgeons, and surgery as a career. They were divided into the control groups (rotations before July 2003; n = 109) and the experimental group (rotations after July 2003; n = 108). RESULTS: Students in the experimental group had a significantly more favorable impression of a surgeon's lifestyle and work hours than those in the control group. This was especially true of female students post-rotation, who responded more positively to the statement that a surgical career would allow for a good balance between professional and personal life (1.87 vs 2.45, P <.01). CONCLUSION: The new Accreditation Council for Graduate Medical Education (ACGME) regulation has had a positive impact on students' perceptions of the surgeon's lifestyle, but does not necessarily increase their interest in a surgical career.


Subject(s)
General Surgery/education , Personnel Staffing and Scheduling , Accreditation , Adult , Data Collection , Decision Making , Female , Humans , Internship and Residency , Life Style , Male , Sex Factors , Students, Medical , Workforce , Workload
15.
Int J Gynecol Pathol ; 21(1): 11-5, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11781517

ABSTRACT

The histological distinction between a primary endometrial and a primary endocervical adenocarcinoma is often difficult, especially in small biopsy specimens. A preoperative distinction is important because primary surgical management differs between the two tumors. Cases of primary endometrioid endometrial (n=30) and primary endocervical (n=26) adenocarcinoma of endocervical type were stained immunohistochemically with the monoclonal antibodies against carcinoembryonic antigen (CEA), vimentin, estrogen receptor (ER), and 34 beta E12. In all cases the origin of the adenocarcinoma was confirmed by examination of the definitive pathology specimen. There was diffuse positive nuclear staining for ER in 28 of 30 (93%) endometrial adenocarcinomas. ER was negative in 16 of 26 endocervical adenocarcinomas, and there was focal weak nuclear staining in the other cases. Vimentin was positive in 29 of 30 (97%) endometrial adenocarcinomas but in only 2 of 26 (8%) endocervical adenocarcinomas. CEA was positive in 25 of 26 (96%) endocervical adenocarcinomas, mostly with diffuse membranous and cytoplasmic staining. Positivity with CEA was present in 21 of 30 (70%) endometrial adenocarcinomas but was largely confined to squamoid areas with only 12 tumors exhibiting focal membranous staining of the glandular component. 34 beta E12 was diffusely positive in all except one cervical adenocarcinoma. In endometrial carcinomas, positivity was strongest in squamoid areas but there was positive staining, either focally or diffusely, of the glandular component in 27 cases. In summary, primary endometrioid endometrial adenocarcinomas are characterized by diffuse, strong, positive staining for vimentin and ER and negative or very focal, positive staining of the glandular component for CEA. In contrast, primary endocervical adenocarcinomas are characterized by CEA positivity, which is usually but not always diffuse, negativity for vimentin, and negativity or focal weak positivity for ER. 34 beta E12 is of no value in the distinction between endometrial and endocervical adenocarcinomas. A panel of immunohistochemical stains, comprising CEA, vimentin, and ER, generally allows confident preoperative distinction between a primary endometrial and endocervical adenocarcinoma.


Subject(s)
Adenocarcinoma/metabolism , Biomarkers, Tumor/biosynthesis , Endometrial Neoplasms/metabolism , Uterine Cervical Neoplasms/metabolism , Adenocarcinoma/diagnosis , Adenocarcinoma/pathology , Antibodies, Monoclonal , Carcinoembryonic Antigen/biosynthesis , Endometrial Neoplasms/diagnosis , Endometrial Neoplasms/pathology , Female , Humans , Immunohistochemistry , Keratins/biosynthesis , Receptors, Estrogen/biosynthesis , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/pathology , Vimentin/biosynthesis
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