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1.
Int J Emerg Med ; 17(1): 110, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227764

RESUMO

BACKGROUND: Bleeding in early pregnancy is a common emergency department (ED) presentation. Although variability in approaches has been demonstrated, research is relatively uncommon on practices and outcomes. This study investigated the influence of clinical pattern of care, utility, and contribution of pelvic examination aimed at diagnosing and managing bleeding in early pregnancy at three Canadian EDs. METHODS: After obtaining informed consent, data were collected from adult women who were pregnant and from treating ED physicians using a structured questionnaire. We defined the change in management based on the initial clinical plan at the time of the initial physician assessment in the ED and any subsequent changes made after the pelvic examination was performed. Patient telephone follow-up was supplemented by linking with provincial administrative data for births. Univariable and multivariable binary logistic regression analyses were performed to identify factors associated with a change in patient management following pelvic examination in the ED. RESULTS: Overall, 200 women were enrolled. The mean age was 31 years, patients had been bleeding for a median of 1 day and stayed in the ED for a median of 5 h. Of these, 166 (83.0%) received a pelvic examination, including speculum examination and/or bimanual palpation. Pregnancy outcome data were available for 192 pregnancies; 107 (56%) experienced a miscarriage. Factors significantly associated with a change in management after pelvic examination in the univariate logistic regression analysis were brown/dark-red bleeding per vaginam (physician determined), tachycardia, right lower quadrant tenderness, and bimanual palpation. In the multivariate logistic regression analysis, brown/dark-red bleeding per vaginam was independently associated with a reduced likelihood of a change in management after pelvic examination (aOR = 0.37; 95% CI: 0.14-0.98). CONCLUSION: Among women presenting to the ED with bleeding in early pregnancy prior to 20 weeks gestation, only brown/dark-red vaginal bleeding, potentially indicative of bleeding resolution, significantly independently influenced the baseline odds of a change in management after pelvic examination. Until the debate on the utility of pelvic examination in the ED for this presentation is resolved, physician preferences and shared decision making with patients should guide practice regarding speculum examination/bimanual palpation for the management of bleeding in early pregnancy.

2.
Int J Mol Sci ; 25(15)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39125629

RESUMO

Photoreceptor degeneration is a major cause of untreatable blindness worldwide and has recently been targeted by emerging technologies, including cell- and gene-based therapies. Cell types of neural lineage have shown promise for replacing either photoreceptors or retinal pigment epithelial cells following delivery to the subretinal space, while cells of bone marrow lineage have been tested for retinal trophic effects following delivery to the vitreous cavity. Here we explore an alternate approach in which cells from the immature neural retinal are delivered to the vitreous cavity with the goal of providing trophic support for degenerating photoreceptors. Rat and human retinal progenitor cells were transplanted to the vitreous of rats with a well-studied photoreceptor dystrophy, resulting in substantial anatomical preservation and functional rescue of vision. This work provides scientific proof-of-principle for a novel therapeutic approach to photoreceptor degeneration that is currently being evaluated in clinical trials.


Assuntos
Retina , Degeneração Retiniana , Transplante de Células-Tronco , Animais , Ratos , Degeneração Retiniana/terapia , Degeneração Retiniana/patologia , Transplante de Células-Tronco/métodos , Humanos , Retina/patologia , Retina/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patologia , Células Fotorreceptoras de Vertebrados/transplante , Modelos Animais de Doenças
3.
Addict Sci Clin Pract ; 19(1): 53, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026326

RESUMO

BACKGROUND: Overdose deaths continue to rise within the United States, despite effective treatments such as buprenorphine and methadone for opioid use disorder (OUD). Mobile medical units with the ability to dispense buprenorphine have been developed to engage patients and eliminate barriers to accessing OUD treatment. This study reports survey responses of patients of a mobile medical unit dispensing buprenorphine in areas of Chicago, IL with high overdose rates. METHODS: All patients who were dispensed buprenorphine via the mobile medical unit were invited to participate in a 7-item anonymous survey between May 24, 2023, and August 25, 2023. The survey included 5-point satisfaction scale, multiple-choice, and open-ended questions. Outcomes included satisfaction with buprenorphine dispensing from the mobile medical unit, satisfaction with filling buprenorphine at a pharmacy in the past, barriers experienced at pharmacies when filling buprenorphine, and whether the client would have started treatment that day if the mobile medical unit had not been present. Satisfaction scale and multiple-choice question responses were assessed using descriptive statistics. Wilcoxon signed-rank test was used to compare median satisfaction levels between receiving buprenorphine from the mobile medical unit versus filling a buprenorphine prescription at a community pharmacy. Open-ended questions were analyzed qualitatively using inductive thematic analysis. RESULTS: 106 unique patients were dispensed buprenorphine from the mobile unit during the study period. Of these patients, 54 (51%) completed the survey. Respondents reported high satisfaction with the buprenorphine dispensing process as a part of a mobile medical unit. Of those who had previously filled buprenorphine at a pharmacy, 83% reported at least one barrier, with delays in prescription dispensing from a community pharmacy, lack of transportation to/from the pharmacy, and opioid withdrawal symptoms being the most common barriers. 87% reported they would not have started buprenorphine that same day if the mobile medical unit had not been present. Nearly half of survey participants reported having taken buprenorphine that was not prescribed to them. Qualitative analysis of open-ended survey responses noted the importance of convenient accessibility, comprehensive care, and a non-judgmental environment. CONCLUSIONS: Mobile medical units that dispense buprenorphine are an innovative model to reach patients with OUD who have significant treatment access barriers. This study found that patients who experienced barriers to accessing buprenorphine from a pharmacy were highly satisfied with the mobile medical unit's buprenorphine dispensing process. Programs seeking to develop mobile buprenorphine dispensing programs should consider patient priorities of accessibility, comprehensive care, and welcoming, non-judgmental environments.


Assuntos
Buprenorfina , Unidades Móveis de Saúde , Tratamento de Substituição de Opiáceos , Transtornos Relacionados ao Uso de Opioides , Satisfação do Paciente , Humanos , Buprenorfina/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Masculino , Feminino , Unidades Móveis de Saúde/organização & administração , Tratamento de Substituição de Opiáceos/métodos , Adulto , Pessoa de Meia-Idade , Chicago , Antagonistas de Entorpecentes/uso terapêutico , Antagonistas de Entorpecentes/administração & dosagem , Inquéritos e Questionários
4.
Front Neurol ; 15: 1286856, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450075

RESUMO

Purpose: Evidence suggests that transcranial direct current stimulation (tDCS) can enhance motor performance and learning of hand tasks in persons with chronic stroke (PCS). However, the effects of tDCS on the locomotor tasks in PCS are unclear. This pilot study aimed to: (1) determine aggregate effects of anodal tDCS combined with step training on improvements of the neural and biomechanical attributes of stepping initiation in a small cohort of persons with chronic stroke (PCS) over a 4-week training program; and (2) assess the feasibility and efficacy of this novel approach for improving voluntary stepping initiation in PCS. Methods: A total of 10 PCS were randomly assigned to one of two training groups, consisting of either 12 sessions of VST paired with a-tDCS (n = 6) or sham tDCS (s-tDCS, n = 4) over 4 weeks, with step initiation (SI) tests at pre-training, post-training, 1-week and 1-month follow-ups. Primary outcomes were: baseline vertical ground reaction force (B-vGRF), response time (RT) to initiate anticipatory postural adjustment (APA), and the retention of B-VGRF and RT. Results: a-tDCS paired with a 4-week VST program results in a significant increase in paretic weight loading at 1-week follow up. Furthermore, a-tDCS in combination with VST led to significantly greater retention of paretic BWB compared with the sham group at 1 week post-training. Clinical implications: The preliminary findings suggest a 4-week VST results in improved paretic limb weight bearing (WB) during SI in PCS. Furthermore, VST combined with a-tDCS may lead to better retention of gait improvements (NCT04437251) (https://classic.clinicaltrials.gov/ct2/show/NCT04437251).

5.
Am J Physiol Heart Circ Physiol ; 326(3): H860-H869, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38276948

RESUMO

Targeting alternative exons for therapeutic gain has been achieved in a few instances and potentially could be applied more broadly. The myosin phosphatase (MP) enzyme is a critical hub upon which signals converge to regulate vessel tone. Alternative exon 24 of myosin phosphatase regulatory subunit (Mypt1 E24) is an ideal target as toggling between the two isoforms sets smooth muscle sensitivity to vasodilators such as nitric oxide (NO). This study aimed to develop a gene-based therapy to suppress splicing of Mypt1 E24 thereby switching MP enzyme to the NO-responsive isoform. CRISPR/Cas9 constructs were effective at editing of Mypt1 E24 in vitro; however, targeting of vascular smooth muscle in vivo with AAV9 was inefficient. In contrast, an octo-guanidine conjugated antisense oligonucleotide targeting the 5' splice site of Mypt1 E24 was highly efficient in vivo. It reduced the percent splicing inclusion of Mypt1 E24 from 80% to 10% in mesenteric arteries. The maximal and half-maximal effects occurred at 12.5 and 6.25 mg/kg, respectively. The effect persisted for at least 1 mo without toxicity. This highly effective splice-blocking antisense oligonucleotide could be developed as a novel therapy to reverse vascular dysfunction common to diseases such as hypertension and heart failure.NEW & NOTEWORTHY Alternative exon usage is a major driver of phenotypic diversity in all cell types including smooth muscle. However, the functional significance of most of the hundreds of thousands of alternative exons has not been defined, nor in most cases even tested. If their importance to vascular function were known these alternative exons could represent novel therapeutic targets. Here, we present injection of Vivo-morpholino splice-blocking antisense oligonucleotides as a simple, efficient, and cost-effective method for suppression of alternative exon usage in vascular smooth muscle in vivo.


Assuntos
Músculo Liso Vascular , Oligonucleotídeos Antissenso , Músculo Liso Vascular/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Antissenso/uso terapêutico , Fosfoproteínas Fosfatases/metabolismo , Éxons , Isoformas de Proteínas/metabolismo , Processamento Alternativo , Fosforilação
6.
Physiol Rep ; 11(21): e15844, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37960982

RESUMO

Smoothelins are cytoskeletal proteins with a single C-terminal calponin homology domain type 2 (CHD2). Little is known about the significance of variation in SMTN CHD2 domains, addressed here through analysis of public databases. A conserved 152 nt penultimate constitutive exon present in all SMTNs encodes helices II-IV of CHD2 with high identity (nt/aa 63/65%). Variable CHD2s of SMTN (helices IV-VI) are generated by alternative splicing of 165 nt exon E20. E20 and the CHD2 it encodes have high homology with the terminal constitutive exon of SMTNL1 (E8; nt/aa 72/75% identity). Unique to these CHD2 variants are a conserved extended nine amino acid C-terminal tail containing KTKK ubiquitination motifs. When E20 of SMTN is skipped (SMTN E20-), constitutive terminal E21 codes for helices IV-VI of CHD2. SMTN E21 has high identity with the terminal exon of SMTNL2 (E8; nt/aa 75/81% identity of aligned sequences) except for coding for a unique extended C-terminus (24 nt; 8aa) conserved only in mammals. SMTN isoform expression is tissue-specific: SMTNE20- and SMTNE20+ are highly expressed in SMC and non-muscle cells, respectively, while SMTNL1 + 2 are highly expressed in skeletal muscle cells. Tissue-specific expression of SMTN CHD2s with unique helices IV-VI suggest tissue-specific functions that require further study.


Assuntos
Proteínas dos Microfilamentos , Proteínas Musculares , Animais , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas do Citoesqueleto/metabolismo , Mamíferos/metabolismo , Calponinas
7.
J Neurosci ; 43(30): 5468-5482, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37414561

RESUMO

The rod photoreceptor synapse is the first synapse of dim-light vision and one of the most complex in the mammalian CNS. The components of its unique structure, a presynaptic ribbon and a single synaptic invagination enclosing several postsynaptic processes, have been identified, but disagreements about their organization remain. Here, we have used EM tomography to generate high-resolution images of 3-D volumes of the rod synapse from the female domestic cat. We have resolved the synaptic ribbon as a single structure, with a single arciform density, indicating the presence of one long site of transmitter release. The organization of the postsynaptic processes, which has been difficult to resolve with past methods, appears as a tetrad arrangement of two horizontal cell and two rod bipolar cell processes. Retinal detachment severely disrupts this organization. After 7 d, EM tomography reveals withdrawal of rod bipolar dendrites from most spherules; fragmentation of synaptic ribbons, which lose their tight association with the presynaptic membrane; and loss of the highly branched telodendria of the horizontal cell axon terminals. After detachment, the hilus, the opening through which postsynaptic processes enter the invagination, enlarges, exposing the normally sequestered environment within the invagination to the extracellular space of the outer plexiform layer. Our use of EM tomography provides the most accurate description to date of the complex rod synapse and details changes it undergoes during outer segment degeneration. These changes would be expected to disrupt the flow of information in the rod pathway.SIGNIFICANCE STATEMENT Ribbon-type synapses transmit the first electrical signals of vision and hearing. Despite their crucial role in sensory physiology, the three-dimensional ultrastructure of these synapses, especially the complex organization of the rod photoreceptor synapse, is not well understood. We used EM tomography to obtain 3-D imaging at nanoscale resolution to help resolve the organization of rod synapses in normal and detached retinas. This approach has enabled us to show that in the normal retina a single ribbon and arciform density oppose a tetrad of postsynaptic processes. In addition, it enabled us to provide a 3-D perspective of the ultrastructural changes that occur in response to retinal detachment.


Assuntos
Descolamento Retiniano , Feminino , Animais , Gatos , Microscopia Eletrônica , Sinapses/metabolismo , Retina/ultraestrutura , Células Bipolares da Retina , Células Fotorreceptoras Retinianas Bastonetes/ultraestrutura , Mamíferos
8.
Chem Commun (Camb) ; 58(75): 10580-10582, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36073739

RESUMO

Discovered by Knöth in 1964, the 10-vertex closo-carborane anion [HCB9H91-] is a classical bicapped square antiprism that contains an unusual pentacoordinate carbon center. Compared to its larger icosahedral cousin [HCB11H111-], few investigations have been made into its use as a weakly coordinating anion or as a ligand substituent. Here we show that it is possible to prepare both a dianionic N-heterocyclic carbene (NHC) Li+ adduct as well as a trianionic C-2, C-5 dilithio species featuring two 10-vertex carborane anion substituents. All compounds were characterized via multinuclear NMR spectroscopy, single crystal X-ray diffraction, and HRMS when possible.

9.
Cell Mol Life Sci ; 79(8): 459, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35913515

RESUMO

Differentiation of smooth muscle cells (SMCs) depends on serum response factor (SRF) and its co-activator myocardin (MYOCD). The role of MYOCD for the SMC program of gene transcription is well established. In contrast, the role of MYOCD in control of SMC-specific alternative exon usage, including exon splicing, has not been explored. In the current work we identified four splicing factors (MBNL1, RBPMS, RBPMS2, and RBFOX2) that correlate with MYOCD across human SMC tissues. Forced expression of MYOCD family members in human coronary artery SMCs in vitro upregulated expression of these splicing factors. For global profiling of transcript diversity, we performed RNA-sequencing after MYOCD transduction. We analyzed alternative transcripts with three different methods. Exon-based analysis identified 1637 features with differential exon usage. For example, usage of 3´ exons in MYLK that encode telokin increased relative to 5´ exons, as did the 17 kDa telokin to 130 kDa MYLK protein ratio. Dedicated event-based analysis identified 239 MYOCD-driven splicing events. Events involving MBNL1, MCAM, and ACTN1 were among the most prominent, and this was confirmed using variant-specific PCR analyses. In support of a role for RBPMS and RBFOX2 in MYOCD-driven splicing we found enrichment of their binding motifs around differentially spliced exons. Moreover, knockdown of either RBPMS or RBFOX2 antagonized splicing events stimulated by MYOCD, including those involving ACTN1, VCL, and MBNL1. Supporting an in vivo role of MYOCD-SRF-driven splicing, we demonstrate altered Rbpms expression and splicing in inducible and SMC-specific Srf knockout mice. We conclude that MYOCD-SRF, in part via RBPMS and RBFOX2, induce a program of differential exon usage and alternative splicing as part of the broader program of SMC differentiation.


Assuntos
Processamento Alternativo , Miócitos de Músculo Liso , Processamento Alternativo/genética , Animais , Diferenciação Celular/genética , Éxons/genética , Humanos , Camundongos , Miócitos de Músculo Liso/metabolismo , Proteínas Nucleares , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Proteínas Repressoras/metabolismo , Transativadores
10.
J Occup Environ Hyg ; 19(3): 169-184, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35285785

RESUMO

Following the introduction of lead-free frangible ammunition in United States Air Force small arms firing ranges, Combat Arms instructors have routinely reported experiencing adverse health symptoms during live fire training exercises, including sore throat, cough, and headache. Previous studies have found that these symptoms occur despite occupational exposure limits not being exceeded. To better characterize the potential source and mechanisms for health symptoms, a comprehensive characterization of the physicochemical properties of gases and aerosols emitted during the firing of the M9 pistol and M4 rifle using lead-free frangible ammunition was completed. Weapons were fired within a sealed chamber using a remote firing mechanism. A suite of direct-reading instruments and collection-based analytical methods were used to determine the composition of the emissions. Emissions were dominated by carbon monoxide and ultrafine particles. Other prevalent gases included carbon dioxide, ammonia, formaldehyde, hydrogen cyanide, and nitric oxide when measured using Fourier-transform infrared spectroscopy. An electrical, low-pressure impactor showed that, on average, the count median diameter immediately after firing was 36 ± 4 nm (n = 10 rounds) and 32 ± 3 nm (n = 14 rounds) for the M9 pistol and M4 rifle, respectively. Analytical methods were used to determine that emitted particles were primarily composed of soot, copper, and potassium, with trace amounts of calcium, silicon, sodium, sulfur, and zinc. Results from this research confirm prior work and expand upon the characterization of emissions generated from firing lead-free frangible ammunition. By employing multiple methods to measure and analyze data we were able to quantify both total and respirable particle fractions and determine particle morphology and composition. Characterization of the emissions provides insight into potential exposure risks that may lead to the development of adverse health symptoms allowing for the development of strategies for risk mitigation.


Assuntos
Armas de Fogo , Exposição Ocupacional , Monóxido de Carbono/análise , Gases , Exposição Ocupacional/análise , Material Particulado
11.
Am J Physiol Regul Integr Comp Physiol ; 322(4): R281-R291, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35107022

RESUMO

Alternative splicing of exon24 (E24) of myosin phosphatase targeting subunit 1 (Mypt1) by setting sensitivity to nitric oxide (NO)/cGMP-mediated relaxation is a key determinant of smooth muscle function. Here we defined expression of myosin phosphatase (MP) subunits and isoforms by creation of new genetic mouse models, assay of human and mouse tissues, and query of public databases. A Mypt1-LacZ reporter mouse revealed that Mypt1 transcription is turned on early in development during smooth muscle differentiation. Mypt1 is not as tightly restricted in its expression as smooth muscle myosin heavy chain (Myh11) and its E6 splice variant. Mypt1 is enriched in mature smooth versus nonmuscle cells. The E24 splice variant and leucine zipper minus protein isoform that it encodes is enriched in phasic versus tonic smooth muscle. In the vascular system, E24 splicing increases as vessel size decreases. In the gastrointestinal system, E24 splicing is most predominant in smooth muscle of the small intestine. Tissue-specific expression of MP subunits and Mypt1 E24 splicing is conserved in humans, whereas a splice variant of the inhibitory subunit (CPI-17) is unique to humans. A Mypt1 E24 mini-gene splicing reporter mouse generated to define patterns of E24 splicing in smooth muscle cells (SMCs) dispersed throughout the organ systems was unsuccessful. In summary, expression of Mypt1 and splicing of E24 is part of the program of smooth muscle differentiation, is further enhanced in phasic smooth muscle, and is conserved in humans. Its low-level expression in nonmuscle cells may confound its measurement in tissue samples.


Assuntos
Músculo Liso Vascular , Miócitos de Músculo Liso , Fosfatase de Miosina-de-Cadeia-Leve , Animais , GMP Cíclico/metabolismo , Humanos , Camundongos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/genética , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo , Fosforilação , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
12.
Front Physiol ; 12: 710968, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539433

RESUMO

Myocardin-related transcription factors (MRTFs: myocardin/MYOCD, MRTF-A/MRTFA, and MRTF-B/MRTFB) are co-factors of serum response factor (SRF) that activate the smooth muscle cell (SMC) gene program and that play roles in cardiovascular development and mechanobiology. Gain and loss of function experiments have defined the SMC gene program under control of MRTFs, yet full understanding of their impact is lacking. In the present study, we tested the hypothesis that the muscarinic M3 receptor (CHRM3) is regulated by MRTFs together with SRF. Forced expression of MYOCD (8d) in human coronary artery (SMC) followed by RNA-sequencing showed increased levels of M2, M3, and M5 receptors (CHRM2: 2-fold, CHRM3: 16-fold, and CHRM5: 2-fold). The effect of MYOCD on M3 was confirmed by RT-qPCR using both coronary artery and urinary bladder SMCs, and correlation analyses using human transcriptomic datasets suggested that M3 may also be regulated by MRTF-B. Head-to-head comparisons of MYOCD, MRTF-A and MRTF-B, argued that while all MRTFs are effective, MRTF-B is the most powerful transactivator of CHRM3, causing a 600-fold increase at 120h. Accordingly, MRTF-B conferred responsiveness to the muscarinic agonist carbachol in Ca2+ imaging experiments. M3 was suppressed on treatment with the MRTF-SRF inhibitor CCG-1423 using SMCs transduced with either MRTF-A or MRTF-B and using intact mouse esophagus in culture (by 92±2%). Moreover, silencing of SRF with a short hairpin reduced CHRM3 (by >60%) in parallel with α-actin (ACTA2). Tamoxifen inducible knockout of Srf in smooth muscle reduced Srf (by 54±4%) and Chrm3 (by 41±6%) in the urinary bladder at 10days, but Srf was much less reduced or unchanged in aorta, ileum, colon, trachea, and esophagus. Longer induction (21d) further accentuated the reduction of Chrm3 in the bladder and ileum, but no change was seen in the aorta. Single cell RNA-sequencing revealed that Mrtfb dominates in ECs, while Myocd dominates in SMCs, raising the possibility that Chrm3 may be driven by Mrtfb-Srf in the endothelium and by Myocd-Srf in SMCs. These findings define a novel transcriptional control mechanism for muscarinic M3 receptors in human cells, and in mice, that could be targeted for therapy.

13.
Pflugers Arch ; 473(4): 611-622, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33145641

RESUMO

Alternative splicing of exon 24 (E24) of the myosin phosphatase regulatory subunit (Mypt1) tunes smooth muscle sensitivity to NO/cGMP-mediated vasorelaxation and thereby controls blood pressure (BP) in otherwise normal mice. This occurs via the toggling in or out of a C-terminal leucine zipper (LZ) motif required for hetero-dimerization with and activation by cGMP-dependent protein kinase cGK1α. Here we tested the hypothesis that editing (deletion) of E24, by shifting to the LZ positive isoform of Mypt1, would suppress the hypertensive response to angiotensin II (AngII). To test this, mice underwent tamoxifen-inducible and smooth muscle-specific deletion of E24 (E24 cKO) at age 6 weeks followed by a chronic slow-pressor dose of AngII (400 ng/kg/min) plus additional stressors. E24 cKO suppressed the hypertensive response to AngII alone or with the addition of a high salt diet. This effect was not a function of altered salt balance as there were no differences in intake or renal excretion of sodium. This effect was NO dependent as L-NAME in the drinking water caused an exaggerated hypertensive response in the E24cKO mice. E24cKO mouse mesenteric arteries were more sensitive to DEA/NO-induced vasorelaxation and less responsive to AngII- and α-adrenergic-induced vasoconstriction at baseline. Only the latter two effects were still present after 2 weeks of chronic AngII treatment. We conclude that editing of Mypt1 E24, by shifting the expression of naturally occurring isoforms and sensitizing to NO-mediated vasodilation, could be a novel approach to the treatment of human hypertension.


Assuntos
Angiotensina II/metabolismo , Hipertensão/metabolismo , Fosfatase de Miosina-de-Cadeia-Leve/genética , Óxido Nítrico/metabolismo , Vasodilatação , Animais , Hipertensão/genética , Hipertensão/fisiopatologia , Zíper de Leucina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiologia , Mutação , Fosfatase de Miosina-de-Cadeia-Leve/química , Fosfatase de Miosina-de-Cadeia-Leve/metabolismo
14.
Orthopedics ; 43(3): e147-e150, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32077967

RESUMO

Total hip arthroplasty (THA) is one of the most successful orthopedic surgeries performed in the United States. Orthopedic surgeons have looked to minimally invasive approaches for THA to reduce peri- and postoperative complications, and to improve patients' quality of life; the anterior approach THA has been advocated as such a minimally invasive surgery. This study involved a retrospective chart review of 2647 consecutive unilateral THAs using the anterior approach. The following parameters and complications were examined: patient demographics, surgery duration (open to close), postoperative length of stay, intraoperative fractures requiring internal fixation, femoral or sciatic nerve injuries with or without motor loss, deep infections managed with operative irrigation and debridement, deep venous thromboses (DVTs), and dislocations. Mean patient age and body mass index were 65 years and 29.78 kg/m2, respectively. Mean length of surgery was 69.1 minutes, and mean length of stay was 1.6 days postoperatively. The complication rates were as follows: dislocations, 19 (0.72%); DVT, 12 (0.45%); fractures, 13 (0.49%); infections, 49 (1.85%); and nerve injuries, 11 (0.42%). These findings demonstrate the anterior approach to THA has very low complication rates and acceptably low rates of infection. In addition, the minimally invasive THA has an acceptably low duration and a substantially reduced length of stay compared with more traditional THA approaches. [Orthopedics. 2020;43(3):e147-e150.].


Assuntos
Artroplastia de Quadril/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/métodos , Índice de Massa Corporal , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Qualidade de Vida , Estudos Retrospectivos , Adulto Jovem
15.
J Am Chem Soc ; 142(1): 251-256, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31804820

RESUMO

Weakly coordinating anions (WCAs) are generally tailored to act as spectators with little or no function. Here we describe the implementation of strongly coordinating dianionic carboranyl N-heterocyclic carbenes (NHCs) to create organometallic -ate complexes of Au(I) that serve both as WCAs and functional catalysts. These organometallic WCAs can be utilized to form both heterobimetallic (Au(I)-/Ag(I)+; Au(I)-/Ir(I)+) and organometallic/main group ion pairs (Au(I)-/(CPh3+ or SiEt3+). Because parent unfunctionalized dianionic carboranyl NHC complex 3 is unstable in most solvents when paired with CPh3+, novel synthesis methodology was devised to create polyhalogenated carboranyl NHCs, which show superior stability toward electrophilic substitution and cyclometalation chemistry. Additionally, the WCAs containing polyhalogenated carboranyl NHCs are among the most active catalysts reported for the hydroamination of alkynes. This investigation has also produced the first examples of a low-coordinate Au(III) center with two cis accessible coordination sites and the first true dianionic carbene. These studies pave the way for the design of functional ion pairs that have the potential to participate in tandem or cooperative small-molecule activation and catalysis.

16.
J Am Chem Soc ; 141(23): 9140-9144, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31082208

RESUMO

Here we report the surprising discovery that high-energy vinyl carbocations can be generated under strongly basic conditions, and that they engage in intramolecular sp3 C-H insertion reactions through the catalysis of weakly coordinating anion salts. This approach relies on the unconventional combination of lithium hexamethyldisilazide base and the commercially available catalyst, triphenylmethylium tetrakis(pentafluorophenyl)borate. These reagents form a catalytically active lithium species that enables the application of vinyl cation C-H insertion reactions to heteroatom-containing substrates.


Assuntos
Compostos de Boro/química , Compostos de Lítio/química , Hidrocarbonetos Policíclicos Aromáticos/química , Silanos/química , Compostos de Boro/síntese química , Catálise , Cátions , Eletroquímica , Estrutura Molecular , Hidrocarbonetos Policíclicos Aromáticos/síntese química
17.
J Gerontol A Biol Sci Med Sci ; 74(10): 1628-1636, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30906944

RESUMO

BACKGROUND: Physical function declines during hospitalization in geriatric patients, increasing the risk of loss of independence. There is a need for evidence-based, pragmatic interventions to improve functional recovery of older adults following acute hospitalization. Here, we report the results of a Phase I randomized clinical trial designed to determine safety and effect size of protein supplementation, exercise, and testosterone interventions on 30-day post-discharge functional recovery and readmissions in geriatric patients. METHODS: A total of 100 patients admitted to the University of Texas Medical Branch hospital for an acute medical illness were randomized to one of five intervention groups: isocaloric placebo, whey protein supplement, in-home rehabilitation + placebo, in-home rehabilitation + whey protein, or testosterone. Primary outcome measure was the change from baseline in short physical performance battery score at 1 and 4 weeks post-discharge. Secondary outcomes were changes in body composition, activities of daily living, and 30-day readmissions. Comparisons were made across study groups and between placebo and all active intervention groups. RESULTS: Four weeks post-discharge, the short physical performance battery total score and balance score increased more in active intervention groups than placebo group (p < .05). There were no significant differences in change in body composition or activities of daily living across groups or between active intervention groups and placebo group. Readmission rates were highest in placebo (28%), followed by rehabilitation + placebo (15%), whey protein (12%), rehabilitation + whey protein (11%), and testosterone (5%). There was a trend for lower readmission rates in all active intervention groups (11%) versus placebo group (28%). CONCLUSIONS: Findings from this Phase I clinical trial suggest that pragmatic, evidence-based interventions may accelerate recovery from acute hospitalization in geriatric patients. These data provide essential information to design larger randomized controlled trials to test the effectiveness of these interventions.


Assuntos
Androgênios/uso terapêutico , Dieta , Terapia por Exercício , Hospitalização , Recuperação de Função Fisiológica , Testosterona/uso terapêutico , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Suplementos Nutricionais , Feminino , Avaliação Geriátrica , Humanos , Masculino , Proteínas do Soro do Leite/uso terapêutico
18.
Sci Transl Med ; 11(485)2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-30918111

RESUMO

Tau inclusions are a shared feature of many neurodegenerative diseases, among them frontotemporal dementia caused by tau mutations. Treatment approaches for these conditions include targeting posttranslational modifications of tau proteins, maintaining a steady-state amount of tau, and preventing its tendency to aggregate. We discovered a new regulatory pathway for tau degradation that operates through the farnesylated protein, Rhes, a GTPase in the Ras family. Here, we show that treatment with the farnesyltransferase inhibitor lonafarnib reduced Rhes and decreased brain atrophy, tau inclusions, tau sumoylation, and tau ubiquitination in the rTg4510 mouse model of tauopathy. In addition, lonafarnib treatment attenuated behavioral abnormalities in rTg4510 mice and reduced microgliosis in mouse brain. Direct reduction of Rhes in the rTg4510 mouse by siRNA reproduced the results observed with lonafarnib treatment. The mechanism of lonafarnib action mediated by Rhes to reduce tau pathology was shown to operate through activation of lysosomes. We finally showed in mouse brain and in human induced pluripotent stem cell-derived neurons a normal developmental increase in Rhes that was initially suppressed by tau mutations. The known safety of lonafarnib revealed in human clinical trials for cancer suggests that this drug could be repurposed for treating tauopathies.


Assuntos
Farnesiltranstransferase/antagonistas & inibidores , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Feminino , Proteínas de Ligação ao GTP/antagonistas & inibidores , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Mutação , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Piperidinas/farmacologia , Proteólise/efeitos dos fármacos , Piridinas/farmacologia , RNA Interferente Pequeno/genética , Tauopatias/patologia , Pesquisa Translacional Biomédica , Proteínas tau/genética , Proteínas tau/metabolismo
19.
Chem Commun (Camb) ; 55(12): 1684-1701, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30666325

RESUMO

This feature article covers new directions in the fundamental and applied chemistry of the closo-carborane anions [HCB11H11]- and [HCB9H9]-, as well as some related chemistry with the dicarbolide ion [H2C2B9]2-. Specifically the manuscript will focus on summarizing the authors' as well as related novel contributions to the field. The application of such clusters as solution based electolytes for Mg batteries and related materials for ionic liquids will be discussed. In addition, the preparation of heterocycles and radicals fused to carborane anions will be discussed as well as various novel chemical transformations. Furthermore, new developments in anionic carboranyl phosphines and N-heterocyclic carbenes in the context of catalysis will be summarized.

20.
Birth Defects Res ; 110(20): 1517-1530, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30576091

RESUMO

Low oxygen concentration (hypoxia) is part of normal embryonic development, yet the situation is complex. Oxygen (O2 ) is a janus gas with low levels signaling through hypoxia-inducible transcription factor (HIF) that are required for development of fetal and placental vasculature and fetal red blood cells. This results in coupling of fetus and mother around midgestation as a functional feto-placental unit (FPU) for O2 transport, which is required for continued growth and development of the fetus. Defects in these processes may leave the developing fetus vulnerable to O2 deprivation or other stressors during this critical midgestational transition when common septal and conotruncal heart defects (CHDs) are likely to arise. Recent human epidemiological and case-control studies support an association between placental dysfunction, manifest as early onset pre-eclampsia (PE) and increased serum bio-markers, and CHD. Animal studies support this association, in particular those using gene inactivation in the mouse. Sophisticated methods for gene inactivation, cell fate mapping, and a quantitative bio-reporter of O2 concentration support the premise that hypoxic stress at critical stages of development leads to CHD. The secondary heart field contributing to the cardiac outlet is a key target, with activation of the un-folded protein response and abrogation of FGF signaling or precocious activation of a cardiomyocyte transcriptional program for differentiation, suggested as mechanisms. These studies provide a strong foundation for further study of feto-placental coupling and hypoxic stress in the genesis of human CHD.


Assuntos
Hipóxia/embriologia , Troca Materno-Fetal/fisiologia , Oxigênio/metabolismo , Animais , Estudos de Casos e Controles , Modelos Animais de Doenças , Feminino , Feto/fisiopatologia , Idade Gestacional , Cardiopatias Congênitas/etiologia , Humanos , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Camundongos , Oxigênio/fisiologia , Placenta/metabolismo , Placenta/fisiopatologia , Placentação/fisiologia , Pré-Eclâmpsia/etiologia , Gravidez , Cuidado Pré-Natal , Ratos , Transdução de Sinais
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