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1.
Inorg Chem ; 63(17): 7754-7769, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38625043

RESUMO

The reactivity of six MnIV-oxo complexes in C-H bond oxidation has been examined using a combination of kinetic experiments and computational methods. Variable-temperature studies of the oxidation of 9,10-dihydroanthracene (DHA) and ethylbenzene by these MnIV-oxo complexes yielded activation parameters suitable for evaluating electronic structure computations. Complementary kinetic experiments of the oxidation of deuterated DHA provided evidence for hydrogen-atom tunneling in C-H bond oxidation for all MnIV-oxo complexes. These results are in accordance with the Bell model, where tunneling occurs near the top of the transition-state barrier. Density functional theory (DFT) and DLPNO-CCSD(T1) computations were performed for three of the six MnIV-oxo complexes to probe a previously predicted multistate reactivity model. The DFT computations predicted a thermal crossing from the 4B1 ground state to a 4E state along the C-H bond oxidation reaction coordinate. DLPNO-CCSD(T1) calculations further confirm that the 4E transition state offers a lower energy barrier, reinforcing the multistate reactivity model for these complexes. We discuss how this multistate model can be reconciled with recent computations that revealed that the kinetics of C-H bond oxidation by this set of MnIV-oxo complexes can be well-predicted on the basis of the thermodynamic driving force for these reactions.

2.
Am J Ther ; 31(3): e258-e267, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38691665

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is characterized by loss of motor neurons due to degeneration of nerve cells within the brain and spinal cord. Early symptoms include limb weakness, twitching or muscle cramping, and slurred speech. As the disease progresses, difficulty breathing, swallowing, and paralysis can lead to death. Currently, there are no medications that cure ALS, and guidelines recommend treatments focused on symptom management. Intravenous (IV) edaravone was approved by the US Food and Drug Administration (FDA) in 2017 as a treatment to slow the progression of ALS. In May 2022, the FDA approved an oral suspension (ORS) formulation of edaravone. MECHANISM OF ACTION: The mechanism of action of edaravone is not well defined. However, its neuroprotective effects are thought to result from antioxidant properties occurring through elimination of free radicals. PHARMACOKINETICS: Edaravone ORS (105 mg) has a bioavailability of 57% when compared with edaravone IV (60 mg). The ORS should be taken on an empty stomach in the morning, with water and no food or beverages, for 1 hour. Edaravone is bound to albumin (92%), has a mean volume of distribution of 63.1 L, a half-life of 4.5-9 hours, and a total clearance of 35.9 L/h after intravenous administration. Edaravone is metabolized into nonactive sulfate and glucuronide conjugates. CLINICAL TRIALS: The FDA approval was based on studies of the pharmacokinetics, safety, tolerability, and bioavailability of edaravone ORS. A phase III, global, multicenter, open-label safety study was conducted on edaravone ORS in 185 patients with ALS over 48 weeks. The most reported treatment-emergent adverse events were falls, muscular weakness, and constipation. Serious treatment-emergent adverse events included disease worsening, dysphagia, dyspnea, and respiratory failure. THERAPEUTIC ADVANCE: Oral edaravone is an ALS treatment that can be self-administered or administered by a caregiver, precluding the need for administration by a health care professional in an institutional setting.


Assuntos
Esclerose Lateral Amiotrófica , Edaravone , Fármacos Neuroprotetores , Edaravone/administração & dosagem , Edaravone/farmacologia , Edaravone/uso terapêutico , Humanos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/efeitos adversos , Administração Oral , Suspensões , Disponibilidade Biológica
3.
J Fluoresc ; 34(1): 341-352, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37249676

RESUMO

Diversely substituted methoxy derivatives of arylpiperazinyl-alkyl benzothiazolone has been evaluated as specific probe for 5HT7. To determine the best methoxy derivative for 5HT7 receptor affinity, we synthesised a number of 2-benzothiazolone arylalkyl piperazine derivatives. In-vitro/vivo studies with C-2 substituted [11C]ABT showed 5HT7 specific binding. The radiochemical purity of [11C]ABT was found to be more than 99% with radiochemical stability persistence for more than 1.5 hr at 25 °C. The interaction of BSA and ABT has been analysed by photophysical studies for better understanding of properties such as adsortion, distribution, metabolism and elemination (ADME). The interaction between ABT and BSA was analyzed by using the UV-vis and fluorescence spectra. UV-vis spectra analyzed the changes in primary structure of BSA on its interaction with ABT. ABT showed quenched fluorescence emission intensity of tryptophan residues in BSA via static quenching mechanism. This study might help to understand how ABT binds to serum protein or subsequently to know the ADME of this drug candidate.


Assuntos
Serotonina , Soroalbumina Bovina , Soroalbumina Bovina/química , Serotonina/metabolismo , Espectrometria de Fluorescência , Dicroísmo Circular , Radiobiologia , Ligação Proteica , Termodinâmica
4.
J Nat Prod ; 87(2): 424-438, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38289177

RESUMO

Ever since the isolation of Amycolatopsis mediterranei in 1957, this strain has been the focus of research worldwide. In the last 60 years or more, our understanding of the taxonomy, development of cloning vectors and conjugation system, physiology, genetics, genomics, and biosynthetic pathway of rifamycin B production in A. mediterranei has substantially increased. In particular, the development of cloning vectors, transformation system, characterization of the rifamycin biosynthetic gene cluster, and the regulation of rifamycin B production by the pioneering work of Heinz Floss have made the rifamycin polyketide biosynthetic gene cluster (PKS) an attractive target for extensive genetic manipulations to produce rifamycin B analogues which could be effective against multi-drug-resistant tuberculosis. Additionally, a better understanding of the regulation of rifamycin B production and the application of newer genomics tools, including CRISPR-assisted genome editing systems, might prove useful to overcome the limitations associated with low production of rifamycin analogues.


Assuntos
Actinomycetales , Rifamicinas , Amycolatopsis , Vias Biossintéticas/genética , Rifamicinas/metabolismo
5.
Birth ; 51(1): 209-217, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37849421

RESUMO

BACKGROUND: Traumatic childbirth experiences are common in the United States - affecting a third to a fourth of mothers - with significant negative impacts on maternal health. Yet most research on traumatic childbirth focuses on white mothers' experiences. Drawing on a racially and ethnically diverse sample of mothers who experienced traumatic childbirth, this exploratory qualitative study examined Black, Latina, and Asian mothers' traumatic birth experiences and the role of obstetric racism in shaping these experiences. METHODS: In-depth, semi-structured interviews were conducted in 2019-2020 with 30 mothers who identified as women of color (37% Black, 40% Latina, and 23% Asian) who gave birth in the US and self-identified as having experienced a traumatic childbirth. Data were analyzed using qualitative content analysis. RESULTS: Mothers reported obstetric racism as core to their traumatic birth experiences. This racism manifested through practitioners' use of gendered and racialized stereotypes, denying and delegitimizing mothers' needs. Mothers shared key consequences of the obstetric racism they experienced, including postpartum anxiety and depression, increased medical mistrust, and decreased desire for future children. CONCLUSIONS: Mothers' reports suggest that obstetric racism played a role in their traumatic birth experiences. Particularly, practitioners' deployment of gendered and racialized stereotypes influenced mothers' treatment during birth. These findings point to opportunities to address obstetric racism during childbirth and improve patients' experiences through enhancing their agency and empowerment. The findings, in addition, highlight the need for increased practitioner training in anti-racist practice and cultural humility.


Assuntos
Parto , Racismo , Gravidez , Criança , Feminino , Humanos , Estados Unidos , Confiança , Parto Obstétrico , Mães , Pesquisa Qualitativa
6.
Phytother Res ; 38(2): 556-591, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37919622

RESUMO

Breast Cancer (BC) is the most prevalent type of cancer in the world. Current treatments include surgery, radiation, and chemotherapy but often are associated with high toxicity to normal tissues, chemoresistance, and relapse. Thus, developing novel therapies which could combat these limitations is essential for effective treatment. In this context, phytochemicals are increasingly getting popular due to their safety profile, ability to efficiently target tumors, and circumvent limitations of existing treatments. Essential Oils (EOs) are mixtures of various phytochemicals which have shown potential anticancer activity in preclinical BC models. However, their clinical translation is limited by factors such as high volatility, low stability, and poor solubility. Nanotechnology has facilitated their encapsulation in a variety of nanostructures and proven to overcome these limitations. In this review, we have efficiently summarized the current knowledge on the anticancer effect of EOs and constituents in both in in vitro and in in vivo BC models. Further, we also provide a descriptive account on the potential of nanotechnology in enhancing the anti-BC activity of EOs and their constituents. The papers discussed in this review were selected using the keywords "antiproliferative Essential Oils in breast cancer," "anticancer activity of Essential Oil in breast cancer," and "cytotoxicity of Essential Oils in breast cancer" performed in PubMed and ScienceDirect databases.


Assuntos
Neoplasias da Mama , Óleos Voláteis , Humanos , Feminino , Óleos Voláteis/farmacologia , Óleos Voláteis/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Compostos Fitoquímicos/uso terapêutico
7.
J Arthroplasty ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38657914

RESUMO

BACKGROUND: Despite an increase in outpatient total hip arthroplasty (THA) and total knee arthroplasty (TKA), large-scale data are lacking on current practice for antibiotic prophylaxis prescribing. We aimed to describe current oral antibiotic prophylaxis practices nationally for outpatient THA and TKA. METHODS: This nationwide retrospective cohort study included primary outpatient THA or TKA procedures in patients aged 18 to 64 years from 2018 to 2021 using a national claims database. Oral antibiotic prescriptions filled perioperatively (defined as 5 days before to 3 days after surgery) were extracted; these were categorized and assumed to represent postoperative prophylaxis. Multivariable logistic regression measured associations between patient and surgery characteristics and perioperative oral antibiotic prophylaxis. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) are reported. RESULTS: Oral antibiotic prescriptions were filled in 16.5% of 73,015 outpatient THA and TKA (18.4% of 24,857 THAs, 15.5% of 48,158 TKAs) procedures. Prescriptions were most often for cephalosporins (74.3%), with cephalexin (52.8%), and cefadroxil (19.1%) being the most common. Non-cephalosporin antibiotics prescribed were mainly clindamycin (6.8%), sulfamethoxazole-trimethoprim (6.7%), and doxycycline (6.2%). The odds of receiving oral antibiotic prophylaxis were higher for THA compared to TKA (OR 1.13, 95% CI 1.09 to 1.18, P < .001) and in the presence of obesity, diabetes, and autoimmune conditions (OR 1.08 to 1.13, P < .001 to .01). Ambulatory surgery center procedures also had significantly increased odds of prophylaxis compared to hospital-based outpatient surgeries (OR 2.62, 95% CI 2.51 to 2.73, P < .001). Additionally, regional and time-based variations were noted. CONCLUSIONS: Perioperative oral antibiotic prophylaxis prescriptions were filled in only 16.5% of outpatient THA and TKA cases, with variation in the type of antibiotic prescribed. The receipt of any prophylaxis and specific medications was associated with demographic, clinical, and procedure-related characteristics. Follow-up research will evaluate associations with infection risk reduction.

8.
Int J Obes (Lond) ; 47(10): 986-992, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37474570

RESUMO

INTRODUCTION: Although most patients with NAFLD are obese or overweight, some are lean with normal BMI. Our aim was to assess differences in clinicopathological profile and liver disease severity among lean and non-lean NAFLD. METHODS: Data of 1040 NAFLD patients over last 10 years was analysed. BMI < 23 kg/m2 categorised lean patients. Non-invasive assessment of steatosis was done by ultrasound and controlled attenuation parameter (CAP) while fibrosis was assessed with FIB-4 and liver stiffness measurement (LSM). FibroScan-AST (FAST) score was used for non-invasive prediction of NASH with significant fibrosis. Histology was reported using NASH-CRN system. RESULTS: 149 (14.3%) patients were lean while 891 (85.7%) patients were non-lean. Diabetes mellitus [25 (16.7%) vs 152 (17.05%), p > 0.99], elevated triglycerides [81 (54.3%) vs 525 (58.9%), p = 0.33] and low HDL [71(47.6%) vs 479(53.7%), p = 0.18] were observed in a similar proportion. Lean patients were less likely to have central obesity [72 (48.3%) vs 788 (88.4%), p < 0.001], hypertension [16 (10.7%) vs 239(26.8%), p < 0.001] and metabolic syndrome [21 (14.09%) vs 290 (32.5%), p < 0.001]. No difference in steatosis assessment was noted using ultrasound (p = 0.55) or CAP (0.11). FAST [0.38 (0.18-0.66) vs 0.39 (0.27-0.73), p = 0.53], FIB-4 [1.08 (0.65-1.91) vs 1.09 (0.66-1.94), p = 0.94] and LSM [6.1 (4.8-7.9) vs 6.2 (4.7-8.6), p = 0.19) were similar. Liver biopsy was available in 149 patients [lean: 19 (12.7%), non-lean: 130 (87.3%)]. There was no difference in the number of patients with NASH [4 (21.05%) vs 20 (15.3%), p = 0.51], significant fibrosis [2 (10.5%) vs 32 (24.6%), p = 0.25] or advanced fibrosis [1 (5.26%) vs 18 (13.84%), p = 0.47]. CONCLUSION: Although metabolic co-morbidities are less common, there is no difference in liver disease severity among both groups.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Fígado/diagnóstico por imagem , Fígado/patologia , Fatores de Risco , Obesidade/complicações , Obesidade/patologia , Fibrose , Gravidade do Paciente
9.
Photochem Photobiol Sci ; 22(7): 1543-1559, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36826694

RESUMO

The Eclipta alba plant is considered hepatoprotective, owing to its phytoconstituents wedelolactone. In the current study, effect of elevated ultraviolet-B (eUV-B) radiation was investigated on biochemical, phytochemical, and antioxidative enzymatic activities of E. alba (Bhringraj) plant. The UV-B exposure resulted in an increase in oxidative stress, which has caused an imbalance in phytochemical, biochemical constituents, and induced antioxidative enzymatic activities. It was observed that the UV-B exposure promoted wedelolactone yield by 23.64%. Further, the leaf extract of UV-B-exposed plants was used for the synthesis of carbon quantum dots (CQDs) using low cost, one-step hydrothermal technique and its biocompatibility was studied using in vitro MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay on HepG2 liver cell line. It revealed no toxicity in any treatment groups in comparison to the control. Both CQDs and leaf extract were orally administered to the golden hamster suffering from alcohol-induced liver cirrhosis. In the morphometric study, it was clearly observed that a combination of UV-B-exposed leaf extract and synthesized CQDs delivered the best result with maximum recovery of liver tissues. The present study reveals the positive impact of UV-B exposure on the medicinally important plant, increased yield of wedelolactone, and its enhanced hepatoprotective efficacy for the treatment of damaged liver tissues.


Assuntos
Eclipta , Pontos Quânticos , Animais , Cricetinae , Extratos Vegetais/farmacologia , Mesocricetus , Antioxidantes/farmacologia , Cirrose Hepática , Carbono/farmacologia
10.
Inorg Chem ; 62(45): 18357-18374, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37314463

RESUMO

A series of manganese(II) and oxomanganese(IV) complexes supported by neutral, pentadentate ligands with varied equatorial ligand-field strength (N3pyQ, N2py2I, and N4pyMe2) were synthesized and then characterized using structural and spectroscopic methods. On the basis of electronic absorption spectroscopy, the [MnIV(O)(N4pyMe2)]2+ complex has the weakest equatorial ligand field among a set of similar MnIV-oxo species. In contrast, [MnIV(O)(N2py2I)]2+ shows the strongest equatorial ligand-field strength for this same series. We examined the influence of these changes in electronic structure on the reactivity of the oxomanganese(IV) complexes using hydrocarbons and thioanisole as substrates. The [MnIV(O)(N3pyQ)]2+ complex, which contains one quinoline and three pyridine donors in the equatorial plane, ranks among the fastest MnIV-oxo complexes in C-H bond and thioanisole oxidation. While a weak equatorial ligand field has been associated with high reactivity, the [MnIV(O)(N4pyMe2)]2+ complex is only a modest oxidant. Buried volume plots suggest that steric factors dampen the reactivity of this complex. Trends in reactivity were examined using density functional theory (DFT)-computed bond dissociation free energies (BDFEs) of the MnIIIO-H and MnIV ═ O bonds. We observe an excellent correlation between MnIV═O BDFEs and rates of thioanisole oxidation, but more scatter is observed between hydrocarbon oxidation rates and the MnIIIO-H BDFEs.

11.
Bioorg Chem ; 131: 106254, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36528920

RESUMO

Serotonin (5-hydroxytryptamine) is a small molecule that acts both in the central and peripheral nervous system as a neurotransmitter and a hormone, respectively. Serotonin is synthesized via a multi-stage pathway beginning with l-tryptophan, which is converted by an enzyme called tryptophan hydroxylase into L-5-Hydroxytryptophan. It is well-known for its significance in the control of mood, anxiety, depression, and insomnia as well as in normal human functions such as sleep, sexual activity, and appetite. Thus, for medical chemists and pharmaceutical firms, serotonin is one of the most desirable targets. Among the seven different classes of serotonin receptors, the 5-HT1A was one of the first discovered serotonin receptors, and the 5-HT7 was the last addition to the serotonin receptor family. Both the classes were thoroughly examined. 5-HT1A neurotransmission-related dysfunctions are linked to many psychological conditions such as anxiety, depression, and movement disorders. 5-HT7 is a member of the cell surface receptor GPCR superfamily and is regulated by the serotonin neurotransmitter. It has been the focus of intensive research efforts since its discovery, which was prompted by its presence in functionally important regions of the brain. The thalamus and hypothalamus have the highest 5-HT7 receptor densities. They are also found in the hippocampus and cortex at higher densities. Thermoregulation, circadian rhythm, learning and memory, and sleep are all associated with the 5-HT7 receptor. It is also suspected that this receptor may be involved in the control of mood, indicating that it may be a beneficial target for depression treatment. Several differently structured molecules such as aminotetralins, ergolines, arylpiperazines, indolylalkylamines, aporphines, and aryloxyalkyl-amines are known to bind to 5-HT1A and 5-HT7 receptor sites. In brain serotonin receptors 5-HT1A and 5-HT7 are strongly co-expressed in regions involved in depression. However, their functional interaction has not been identified. An overview of the 5-HT1A and 5-HT7 receptor ligands belonging to different chemical groups is mentioned in this review.


Assuntos
Receptores de Serotonina , Serotonina , Humanos , Serotonina/metabolismo , Receptores de Serotonina/metabolismo , Encéfalo/metabolismo , Ansiedade , Sítios de Ligação , Ligantes
12.
Plant Cell Rep ; 42(7): 1147-1161, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37069436

RESUMO

KEY MESSAGE: RbIDL1 and RbIDL4 are up-regulated in an ethylene-responsive manner during rose petal abscission and restored the Arabidopsis ida-2 mutant abscission defect suggesting functional conservation of the IDA pathway in rose. Abscission is an ethylene-regulated developmental process wherein plants shed unwanted organs in a controlled manner. The INFLORESCENCE DEFICIENT IN ABSCISSION family has been identified as a key regulator of abscission in Arabidopsis, encoding peptides that interact with receptor-like kinases to activate abscission. Loss of function ida mutants show abscission deficiency in Arabidopsis. Functional conservation of the IDA pathway in other plant abscission processes is a matter of interest given the discovery of these genes in several plants. We have identified four members of the INFLORESCENCE DEFICIENT IN ABSCISSION-LIKE family from the ethylene-sensitive, early-abscising fragrant rose, Rosa bourboniana. All four are conserved in sequence and possess well-defined PIP, mIDa and EPIP motifs. Three of these, RbIDL1, RbIDL2 and RbIDL4 show a three-fourfold increase in transcript levels in petal abscission zones (AZ) during ethylene-induced petal abscission as well as natural abscission. The genes are also expressed in other floral tissues but respond differently to ethylene in these tissues. RbIDL1 and RbIDL4, the more prominently expressed IDL genes in rose, can complement the abscission defect of the Arabidopsis ida-2 mutant; while, promoters of both genes can drive AZ-specific expression in an ethylene-responsive manner even in Arabidopsis silique AZs indicating recognition of AZ-specific and ethylene-responsive cis elements in their promoters by the abscission machinery of rose as well as Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Inflorescência/metabolismo , Flores/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Etilenos/farmacologia , Etilenos/metabolismo , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/genética
13.
J Liposome Res ; 33(2): 154-169, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35930249

RESUMO

Some breast cancers are caused by hormonal imbalances, such as estrogen and progesterone. These hormones play a function in directing the growth of cancer cells. The hormone receptors in hormone receptor-positive breast cancer lead breast cells to proliferate out of control. Cancer therapy such as hormonal, targeted, radiation is still unsatisfactory because of these challenges namely multiple drug resistance (MDR), off-targeting, severe adverse effects. A novel aromatase inhibitor exemestane (Exe) exhibits promising therapy in breast cancer. This study aims to develop and optimize Exe-loaded lipid nanocapsules (LNCs) by using DSPC, PF68 and olive oil as lipid, surfactant and oil phase, respectively and to characterize the same. The prepared nanocapsules were investigated via in vitro cell culture and in vivo animal models. The LNCs exhibited cytotoxicity in MCF-7 cell lines and enhanced anti-cancer activity and reduced cardiotoxicity in DMBA-induced animal model when compared to the drug. Additionally, in vivo pharmacokinetics revealed a 4.2-fold increased oral bioavailability when compared with Exe suspension. This study demonstrated that oral administration of Exe-loaded LNCs holds promise for the antiestrogenic activity of exemestane in breast cancer.


Assuntos
Nanocápsulas , Neoplasias , Animais , Lipossomos , Androstadienos/farmacologia , Androstadienos/uso terapêutico , Lipídeos , Neoplasias/tratamento farmacológico
14.
Drug Dev Res ; 84(3): 484-513, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36779375

RESUMO

The inadequate information about the in vivo pathological, physiological, and neurological impairments, as well as the absence of in vivo tools for assessing brain penetrance and the efficiency of newly designed drugs, has hampered the development of new techniques for the treatment for variety of new central nervous system (CNS) diseases. The searching sites such as Science Direct and PubMed were used to find out the numerous distinct tracers across 16 CNS targets including tau, synaptic vesicle glycoprotein, the adenosine 2A receptor, the phosphodiesterase enzyme PDE10A, and the purinoceptor, among others. Among the most encouraging are [18 F]FIMX for mGluR imaging, [11 C]Martinostat for Histone deacetylase, [18 F]MNI-444 for adenosine 2A imaging, [11 C]ER176 for translocator protein, and [18 F]MK-6240 for tau imaging. We also reviewed the findings for each tracer's features and potential for application in CNS pathophysiology and therapeutic evaluation investigations, including target specificity, binding efficacy, and pharmacokinetic factors. This review aims to present a current evaluation of modern positron emission tomography tracers for CNS targets, with a focus on recent advances for targets that have newly emerged for imaging in humans.


Assuntos
Encéfalo , Tomografia por Emissão de Pósitrons , Humanos , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Diester Fosfórico Hidrolases/metabolismo
15.
J Microencapsul ; 40(4): 263-278, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36989347

RESUMO

The purpose of this study was to evaluate the drug delivery and therapeutic potential of berberine (Br) loaded nanoformulation in rheumatoid arthritis (RA)-induced animal model. The Br-loaded NLCs (nanostructured lipid carriers) were prepared employing melt-emulsification process, and optimised through Box-Behnken design. The prepared NLCs were assessed for in-vitro and in-vivo evaluations. The optimised NLCs exhibited a mean diameter of 180.2 ± 0.31 nm with 88.32 ± 2.43% entrapment efficiency. An enhanced anti-arthritic activity with reduced arthritic scores to 0.66 ± 0.51, reduction in ankle diameter to 5.80 ± 0.27 mm, decline in paw withdrawal timing, and improvements in walking behaviour were observed in the Br-NLCs treated group. The radiographic images revealed a reduction in bone and cartilage deformation. The Br-NLCs showed promising results in the management of RA disease, can be developed as an efficient delivery system at commercial levels, and may be explored for clinical application after suitable experiments in the future.


Assuntos
Artrite Reumatoide , Berberina , Nanoestruturas , Animais , Portadores de Fármacos/uso terapêutico , Berberina/farmacologia , Berberina/uso terapêutico , Sistemas de Liberação de Medicamentos , Artrite Reumatoide/tratamento farmacológico , Modelos Animais , Lipídeos , Tamanho da Partícula
16.
J Cancer Educ ; 38(4): 1187-1192, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36635535

RESUMO

Diversifying the future cancer research workforce requires that students engage in cancer research, persist in paths toward science, technology, engineering, mathematics, and medicine (STEMM) fields, and choose cancer research careers. The Summer Clinical Oncology Research Experience (SCORE) Program at Memorial Sloan Kettering, designed in 2010 to engage undergraduate (U) and post-baccalaureate (PB) students from diverse backgrounds in cancer research, is an 8-week summer program pairing an U or PB student with a faculty mentor to conduct cancer research. We report demographics and career paths for 2010-2019 SCORE students. Of 116 students, 112 (97%) attended public universities, and 75 (64%) were in their first 2 years of college. Race/ethnicity was Black/African American, 20 (17%); Hispanic/Latinx, 15 (13%); multiracial, five (4%); Asian, 40 (34%); White/Caucasian, 36 (31%). A total of 112 (97%) identified as female; 47 (41%) were first-generation college students, and 85 (73%) were from immigrant families. As of 2021, 114 (98%) persisted in paths toward STEMM careers: 44 (38%) medical school (MS) students, 14 (12%) residents, two (2%) practicing physicians, 12 (10%) pursuing non-MD STEMM advanced degrees, 21 (18%) working in non-MD STEMM fields, 17 (15%) applying to MS, and 4 (3%) U science majors. Cancer research participation significantly increased from 5% pre- to 84% post-SCORE. A total of 63/116 (54%) students subsequently co-authored 152 peer-reviewed publications, including 105 (69%) in oncology. SCORE engaged underrepresented U and PB students in cancer research, and 98% of these students persisted in paths toward STEMM careers. Long-term follow-up is needed to assess the enduring engagement of these underrepresented students in cancer research.


Assuntos
Diversidade, Equidade, Inclusão , Oncologia , Grupos Minoritários , Estudantes de Medicina , Feminino , Humanos , Escolha da Profissão , Oncologia/educação , Grupos Minoritários/educação , Neoplasias , Instituições Acadêmicas
17.
J Neurooncol ; 157(1): 81-90, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35113288

RESUMO

PURPOSE: Circulating tumor cells in cerebrospinal fluid are a quantitative diagnostic tool for leptomeningeal metastases from solid tumors, but their prognostic significance is unclear. Our objective was to evaluate CSF-CTC quantification in predicting outcomes in LM. METHODS: This is a single institution retrospective study of patients with solid tumors who underwent CSF-CTC quantification using the CellSearch® platform between 04/2016 and 06/2019. Information on neuroaxis imaging, CSF results, and survival was collected. LM was diagnosed by MRI and/or CSF cytology. Survival analyses were performed using multivariable Cox proportional hazards modeling, and CSF-CTC splits associated with survival were identified through recursive partitioning analysis. RESULTS: Out of 290 patients with CNS metastases, we identified a cohort of 101 patients with newly diagnosed LM. In this group, CSF-CTC count (median 200 CTCs/3 ml) predicted survival continuously (HR = 1.005, 95% CI: 1.002-1.009, p = 0.0027), and the risk of mortality doubled (HR = 2.84, 95% CI: 1.45-5.56, p = 0.0023) at the optimal cutoff of ≥ 61 CSF-CTCs/3 ml. Neuroimaging findings of LM (assessed by 3 independent neuroradiologists) were associated with a higher CSF-CTC count (median CSF-CTCs range 1.5-4 for patients without radiographic LM vs 200 for patients with radiographic LM, p < 0.001), but did not predict survival. CONCLUSION: Our data shows that CSF-CTCs quantification predicts survival in newly diagnosed LM, and outperforms neuroimaging. CSF-CTC analysis can be used as a prognostic tool in patients with LM and provides quantitative assessment of disease burden in the CNS compartment.


Assuntos
Carcinomatose Meníngea , Células Neoplásicas Circulantes , Biomarcadores Tumorais/líquido cefalorraquidiano , Contagem de Células , Humanos , Carcinomatose Meníngea/líquido cefalorraquidiano , Células Neoplásicas Circulantes/patologia , Prognóstico , Estudos Retrospectivos
18.
Int J Sport Nutr Exerc Metab ; 32(3): 195-203, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35393372

RESUMO

Military training is characterized by high daily energy expenditures which are difficult to match with energy intake, potentially resulting in negative energy balance (EB) and low energy availability (EA). The aim of this study was to quantify EB and EA during British Army Officer Cadet training. Thirteen (seven women) Officer Cadets (mean ± SD: age 24 ± 3 years) volunteered to participate. EB and EA were estimated from energy intake (weighing of food and food diaries) and energy expenditure (doubly labeled water) measured in three periods of training: 9 days on-camp (CAMP), a 5-day field exercise (FEX), and a 9-day mixture of both CAMP and field-based training (MIX). Variables were compared by condition and gender with a repeated-measures analysis of variance. Negative EB was greatest during FEX (-2,197 ± 455 kcal/day) compared with CAMP (-692 ± 506 kcal/day; p < .001) and MIX (-1,280 ± 309 kcal/day; p < .001). EA was greatest in CAMP (23 ± 10 kcal·kg free-fat mass [FFM]-1·day-1) compared with FEX (1 ± 16 kcal·kg FFM-1·day-1; p = .002) and MIX (10 ± 7 kcal·kg FFM-1·day-1; p = .003), with no apparent difference between FEX and MIX (p = .071). Irrespective of condition, there were no apparent differences between gender in EB (p = .375) or EA (p = .385). These data can be used to inform evidenced-based strategies to manage EA and EB during military training, and enhance the health and performance of military personnel.


Assuntos
Militares , Adulto , Ingestão de Energia , Metabolismo Energético , Exercício Físico , Feminino , Humanos , Estado Nutricional , Adulto Jovem
19.
Int J Mol Sci ; 23(22)2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36430446

RESUMO

Lysyl oxidase-2 (LOXL2) is a Cu2+ and lysine tyrosylquinone (LTQ)-dependent amine oxidase that catalyzes the oxidative deamination of peptidyl lysine and hydroxylysine residues to promote crosslinking of extracellular matrix proteins. LTQ is post-translationally derived from Lys653 and Tyr689, but its biogenesis mechanism remains still elusive. A 2.4 Å Zn2+-bound precursor structure lacking LTQ (PDB:5ZE3) has become available, where Lys653 and Tyr689 are 16.6 Å apart, thus a substantial conformational rearrangement is expected to take place for LTQ biogenesis. However, we have recently shown that the overall structures of the precursor (no LTQ) and the mature (LTQ-containing) LOXL2s are very similar and disulfide bonds are conserved. In this study, we aim to gain insights into the spatial arrangement of LTQ and the active site Cu2+ in the mature LOXL2 using a recombinant LOXL2 that is inhibited by 2-hydrazinopyridine (2HP). Comparative UV-vis and resonance Raman spectroscopic studies of the 2HP-inhibited LOXL2 and the corresponding model compounds and an EPR study of the latter support that 2HP-modified LTQ serves as a tridentate ligand to the active site Cu2. We propose that LTQ resides within 2.9 Å of the active site of Cu2+ in the mature LOXL2, and both LTQ and Cu2+ are solvent-exposed.


Assuntos
Lisina , Proteína-Lisina 6-Oxidase , Lisina/metabolismo , Proteína-Lisina 6-Oxidase/metabolismo , Domínio Catalítico , Quinonas/química
20.
Physiol Mol Biol Plants ; 28(4): 719-735, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35592484

RESUMO

Insect wounding activates a large number of signals that function coordinately to modulate gene expression and elicit defense responses. How each signal influences gene expression in absence of wounding is also important since it can shed light on changes occurring during the shift to wound response. Using simulated Helicoverpa armigera herbivory on chickpea, we had identified at least 14 WRKY genes that showed 5-50 fold increase in expression within 5-20 min of wounding. Our studies show that contrary to their collective effects upon wounding, individual chemical cues show distinct and often opposite effects in absence of wounding. In particular, jasmonic acid, a key early defense hormone, reduced transcripts of most WRKY genes by > 50% upon treatment of unwounded chickpea leaves as did salicylic acid. Neomycin (a JA biosynthesis inhibitor) delayed and also reduced early wound expression. H2O2 transiently activated several genes within 5-20 min by 5-8 fold while ethylene activated only a few WRKY genes by 2-5 fold. The summation of the individual effects of these chemical cues does not explain the strong increase in transcript levels upon wounding. Detailed studies of a 931 nt region of the CaWRKY41 promoter, show strong wound-responsive GUS expression in Arabidopsis even in presence of neomycin. Surprisingly its expression was lost in the coi1, ein2 and myc2myc3myc4 mutant backgrounds suggesting the requirement of intact ethylene and JA signaling pathways (dependent on MYCs) for wound-responsive expression. The studies highlight the complexity of gene regulation by different chemical cues in the presence and absence of wounding. Supplementary Information: The online version contains Supplementary material available at 10.1007/s12298-022-01170-y.

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