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Histone deacetylases (HDACs) mediate epigenetic mechanisms implicated in a broad range of central nervous system dysfunction, including neurodegenerative diseases and neuropsychiatric disorders. [11 C]Martinostat allows in vivo quantification of class I/IIb HDACs and may be useful for the quantification of drug-occupancy relationship, facilitating drug development for disease modifying therapies. The present study reports a radiosynthesis of [11 C]martinostat using [11 C]methyl triflate in ethanol, as opposed to the originally described synthesis using [11 C]methyl iodide and DMSO. [11 C]Methyl triflate is trapped in a solution of 2 mg of precursor 1 dissolved in anhydrous ethanol (400 µl), reacted at ambient temperature for 5 min and purified by high-performance liquid chromatography; 1.5-1.8 GBq (41-48 mCi; n = 3) of formulated [11 C]martinostat was obtained from solid-phase extraction using a hydrophilic-lipophilic cartridge in a radiochemical yield of 11.4% ± 1.1% (nondecay corrected to trapped [11 C]MeI), with a molar activity of 369 ± 53 GBq/µmol (9.97 ± 1.3 Ci/µmol) at the end of synthesis (40 min) and validated for human use. This methodology was used at our production site to produce [11 C]martinostat in sufficient quantities of activity to scan humans, including losses incurred from decay during pre-release quality control testing.
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Etanol , Compostos Radiofarmacêuticos , Adamantano/análogos & derivados , Radioisótopos de Carbono/química , Humanos , Ácidos Hidroxâmicos , Mesilatos , Tomografia por Emissão de Pósitrons/métodosRESUMO
A dimolybdenum tetraacetate (Mo2(O2CCH3)4) molecule is embedded between two electrodes formed by semi-infinite 1D monatomic chains of lithium, aluminum, and titanium atoms. Electron transport through the Mo2(O2CCH3)4 molecule is calculated. The role of quadrupole bonding in the transport properties of the studied systems is analyzed.
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We previously showed a hydroxamic acid-based histone deacetylase inhibitor (HDACi), compound 13, provides neuroprotection against chronic cerebral hypoperfusion (CCH) both in vitro under oxygen-glucose deprivation (OGD) conditions and in vivo under bilateral common carotid artery occlusion (BCCAO) conditions. Intriguingly, the protective effect of this HDACi is via H3K14 or H4K5 acetylation-mediated differential BDNF isoform activation. BDNF is involved in cell proliferation and differentiation in development, synaptic plasticity and in learning and memory related with receptors or synaptic proteins. B6 mice underwent BCCAO and were randomized into 4 groups; a sham without BCCAO (sham), BCCAO mice injected with DMSO (DMSO), mice injected with HDACi-compound 13 (compound 13) and mice injected with suberoylanilide hydroxamic acid (SAHA). The cortex and hippocampus of mice were harvested at 3 months after BCCAO, and levels of BDNF, AMPA receptor and dopamine receptors (D1, D2 and D3) were studied using Western blotting analysis or immunohistochemistry. We found that the AMPA receptor plays a key role in the molecular mechanism of this process by modulating HDAC. This protective effect of HDACi may be through BDNF; therefore, activation of this downstream signalling molecule, for example by AMPA receptors, could be a therapeutic target or intervention applied under CCH conditions.
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Fator Neurotrófico Derivado do Encéfalo/metabolismo , Demência Vascular/tratamento farmacológico , Inibidores de Histona Desacetilases/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Receptores de AMPA/metabolismo , Animais , Arteriopatias Oclusivas/complicações , Artérias Carótidas/patologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Demência Vascular/etiologia , Demência Vascular/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologiaRESUMO
INTRODUCTION: Nuclear medicine parathyroid imaging is important in the identification of hyperfunctioning parathyroid glands in primary hyperparathyroidism (pHPT), but it may be also valuable before surgical treatment in secondary hyperparathyroidism (sHPT). Parathyroid radionuclide imaging with scintigraphy or positron emission tomography (PET) is a highly sensitive procedure for the assessment of the presence and number of hyperfunctioning parathyroid glands, located either at typical sites or ectopically. The treatment of pHPT is mostly directed toward minimally invasive parathyroidectomy, especially in cases with a single adenoma. In experienced hands, successful surgery depends mainly on the exact preoperative localization of one or more hyperfunctioning parathyroid adenomas. Failure to preoperatively identify the hyperfunctioning parathyroid gland challenges minimally invasive parathyroidectomy and might require bilateral open neck exploration. METHODS: Over a decade has now passed since the European Association of Nuclear Medicine (EANM) issued the first edition of the guideline on parathyroid imaging, and a number of new insights and techniques have been developed since. The aim of the present document is to provide state-of-the-art guidelines for nuclear medicine physicians performing parathyroid scintigraphy, single-photon emission computed tomography/computed tomography (SPECT/CT), positron emission tomography/computed tomography (PET/CT), and positron emission tomography/magnetic resonance imaging (PET/MRI) in patients with pHPT, as well as in those with sHPT. CONCLUSION: These guidelines are written and authorized by the EANM to promote optimal parathyroid imaging. They will assist nuclear medicine physicians in the detection and correct localization of hyperfunctioning parathyroid lesions.
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Hiperparatireoidismo Primário , Medicina Nuclear , Humanos , Hiperparatireoidismo Primário/diagnóstico por imagem , Glândulas Paratireoides/diagnóstico por imagem , Glândulas Paratireoides/cirurgia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Cintilografia , Sensibilidade e Especificidade , Tecnécio Tc 99m SestamibiRESUMO
Tropisetron and Granisetorn are 5-HT3 antagonists with antiemetic effects. Tropisetron also has a partial agonistic effect on alpha-7 nicotinic acetylcholine receptors (α7 nAChRs). On the other hand, chronic cerebral hypoperfusion (CCH) attenuates cerebral blood flow and impairs cognitive functions. The goal of this study was to investigate the effect of Tropisetron and Granisetron on CCH-induced spatial memory impairment in rats. Forty-eight male Wistar rats were used in this study. 2-VO surgery was done to induce CCH and Radial Eight Arm Maz apparatus was used to evaluate spatial memory (working and reference memory). Tropisetron was injected intraperitoneally at the doses of 1 and 5 mg/kg, and Granisetron was injected intraperitoneally at the dose of 3 mg/kg. Dorsal hippocampal (CA1) neurons count, Interleukin 6 (IL-6) serum level, and serotonin-reuptake transporter (SERT) gene expression were also evaluated. The results showed, CCH impaired working and reference memory, increased IL-6 serum level, and decreased CA1 neurons and SERT expression. Tropisetron at the dose of 5 mg/kg restored all the effects of CCH. However, Granisetron did not restore CCH-induced memory impairment. Furthermore, Granisetron had no effect on IL-6. While, it increased SERT expression and CA1 neurons. In conclusion, Tropisetron but not Granisetron, ameliorated spatial memory impairment induced by CCH. We suggested conducting more detailed studies investigating the role of serotonergic system (5-HT3 receptors and serotonin transporters) and also α7 nAChRs in the effects of Tropisetron.
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Granisetron/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Antagonistas do Receptor 5-HT3 de Serotonina/uso terapêutico , Memória Espacial/efeitos dos fármacos , Tropizetrona/uso terapêutico , Animais , Arteriopatias Oclusivas/complicações , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Artéria Carótida Primitiva/cirurgia , Transtornos Cerebrovasculares/complicações , Interleucina-6/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/etiologia , Neurônios/efeitos dos fármacos , Proteínas de Ligação a RNA/metabolismo , Ratos WistarRESUMO
PURPOSE: Skin tears are an unpleasant complication that may occur after collagenase Clostridium histolyticum (CCH) administration to treat Dupuytren contractures of the fingers. The purpose of this study was to determine risk factors for the development of this complication. METHODS: Over a 6-year period, patients with a measurable metacarpophalangeal or proximal interphalangeal joint Dupuytren contracture and a palpable cord treated with CCH were prospectively observed. Patients were assessed for the development of skin tears immediately on the day of manipulation as well 30 days or more after manipulation. RESULTS: A total of 117 patients (174 cords) met inclusion criteria. There was a 25.6% incidence of skin tears (30 of 117 patients; 33 skin tears). Multivariable regression analysis revealed that patients with a combined digital flexion contracture (total combined metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joint contracture) of 75° and greater and those treated with 2 simultaneous doses of CCH in the same hand were more likely to sustain a tear. All skin tears healed with nonsurgical management at short-term follow-up. CONCLUSIONS: Although a relatively minor complication, skin tears are not well-tolerated by all patients and may change the postinjection course of orthosis use, wound care, and manual activity. Based on these results, patients with digital contractures 75° or greater and those treated with 2 simultaneous doses of CCH in the same hand may be counseled that they have a higher likelihood of developing a skin tear during manipulation. Pretreatment education may reduce anxiety experienced by patients who otherwise unexpectedly develop a skin tear at the time of manipulation. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.
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Contratura de Dupuytren , Colagenase Microbiana , Pele/lesões , Clostridium histolyticum , Contratura de Dupuytren/tratamento farmacológico , Humanos , Injeções Intralesionais , Colagenase Microbiana/efeitos adversos , Fatores de Risco , Resultado do TratamentoRESUMO
BACKGROUND: Traditionally, surgery has been considered the gold standard treatment for Peyronie's disease (PD). Less-invasive alternatives, such as collagenase Clostridium histolyticum (CCH) and traction therapy, have been proposed and proven effective. AIM: To compare cost-effectiveness of management options for PD. METHODS: A Markov analytic model was created to compare the cost-effectiveness of treatment with a novel traction device, RestoreX (RXPTT), vs CCH vs surgery. Outcomes were derived from single-institution, prospective data of 63 men treated with RXPTT, 115 with CCH, and 23 with plication or incision and grafting. Costs were based on 2017 Medicare reimbursement and utility values from the literature. MAIN OUTCOME MEASURES: Model outcomes included complications for each treatment arm, as well as the probability of success, which was defined as ≥20% improvement in curvature. Univariable and multivariable sensitivity analyses were performed to test the robustness of the model. RESULTS: Overall success rates were 96% (surgery), 66% (CCH), and 48% (RXPTT). At 10 years after treatment, RXPTT was the most cost-effective, with mean costs per patient of $883 (RXPTT), $11,419 (surgery), and $33,628 (CCH). CCH and surgery both resulted in a gain of quality adjusted life years (QALYs) relative to RXPTT (9.44 and 9.36 vs 9.27, respectively). Sensitivity analysis demonstrated greater cost-effectiveness for surgery if lower (≤46%) rates of postoperative erectile dysfunction or length loss (≤3%). CCH became more cost-effective at lower costs (≤$16,726) or higher success rates (≥76%). On multivariable sensitivity analysis at a willingness to pay threshold of $100,000/QALY, the most cost-effective strategy was RXPTT in 49%, surgery in 48%, and CCH in 3% of simulations. At a willingness to treat threshold of $150,000/QALY, the most cost-effective treatment option was RXPTT in 33%, surgery in 55%, and CCH in 12% of simulations. CLINICAL IMPLICATIONS: In an era of value-based care, this model can guide cost-effective treatment selection on the basis of provider, patient, and payer characteristics. STRENGTHS & LIMITATIONS: The current study represents the first cost-effectiveness comparison of treatment modalities for PD and is strengthened by prospective data collection, large CCH and traction sample sizes, and robust sensitivity analyses. Consistent with cost-effective models, the model is limited by assumptions and may not apply to all scenarios. CONCLUSIONS: RXPTT represents a more cost-effective method for achieving ≥20% curvature improvement compared with surgery or CCH. Depending on treatment goals, rate of surgical complications, and willingness to pay threshold, surgery and CCH may become more cost-effective in select scenarios. Wymer K, Kohler T, Trost L. Comparative Cost-effectiveness of Surgery, Collagenase Clostridium Histolyticum, and Penile Traction Therapy in Men with Peyronie's Disease in an Era of Effective Clinical Treatment. J Sex Med 2019;16:1421-1432.
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Colagenase Microbiana/uso terapêutico , Induração Peniana/terapia , Pênis/fisiopatologia , Tração/métodos , Análise Custo-Benefício , Humanos , Masculino , Cadeias de Markov , Colagenase Microbiana/economia , Pessoa de Meia-Idade , Induração Peniana/economia , Induração Peniana/fisiopatologia , Estudos Prospectivos , Tração/economia , Resultado do TratamentoRESUMO
Hemocyanins have highly conserved copper-containing active sites that bind oxygen. However, structural differences among the hemocyanins of various mollusks may affect their physicochemical properties. Here, we studied the oxygen-binding cooperativity and affinity of Concholepas concholepas hemocyanin (CCH) and its two isolated subunits over a wide range of temperatures and pH values. Considering the differences in the quaternary structures of CCH and keyhole limpet hemocyanin (KLH), we hypothesized that the heterodidecameric CCH has different oxygen-binding parameters than the homodidecameric KLH. A novel modification of the polarographic method was applied in which rat liver submitochondrial particles containing cytochrome c oxidase were introduced to totally deplete oxygen of the test solution using ascorbate as the electron donor. This method was both sensitive and reproducible. The results showed that CCH, like other hemocyanins, exhibits cooperativity, showing an inverse relationship between the oxygen-binding parameters and temperature. According to their Hill coefficients, KLH has greater cooperativity than CCH at physiological pH; however, CCH is less sensitive to pH changes than KLH. Appreciable differences in binding behavior were found between the CCH subunits: the cooperativity of CCH-A was not only almost double that of CCH-B, but it was also slightly superior to that of CCH, thus suggesting that the oxygen-binding domains of the CCH subunits are different in their primary structure. Collectively, these data suggest that CCH-A is the main oxygen-binding domain in CCH; CCH-B may play a more structural role, perhaps utilizing its surprising predisposition to form tubular polymers, unlike CCH-A, as demonstrated here using electron microscopy.
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Hemocianinas/metabolismo , Moluscos/química , Oxigênio/metabolismo , Animais , Hemocianinas/química , Concentração de Íons de Hidrogênio , Domínios Proteicos , Subunidades ProteicasRESUMO
The neurosurgical endeavor to treat psychiatric patients may have been part of human history since its beginning. The modern era of psychosurgery can be traced to the heroic attempts of Gottlieb Burckhardt and Egas Moniz to alleviate mental symptoms through the ablation of restricted areas of the frontal lobes in patients with disabling psychiatric illnesses. Thanks to the adaptation of the stereotactic frame to human patients, the ablation of large volumes of brain tissue has been practically abandoned in favor of controlled interventions with discrete targets. Consonant with the role of the hypothalamus in the mediation of the most fundamental approach-avoidance behaviors, some hypothalamic nuclei and regions, in particular, have been selected as targets for the treatment of aggressiveness (posterior hypothalamus), pathological obesity (lateral or ventromedial nuclei), sexual deviations (ventromedial nucleus), and drug dependence (ventromedial nucleus). Some recent improvements in outcomes may have been due to the use of stereotactically guided deep brain stimulation and the change of therapeutic focus from categorical diagnoses (such as schizophrenia) to dimensional symptoms (such as aggressiveness), which are nonspecific in terms of formal diagnosis. However, agreement has never been reached on 2 related issues: 1) the choice of target, based on individual diagnoses; and 2) reliable prediction of outcomes related to individual targets. Despite the lingering controversies on such critical aspects, the experience of the past decades should pave the way for advances in the field. The current failure of pharmacological treatments in a considerable proportion of patients with chronic disabling mental disorders is reminiscent of the state of affairs that prevailed in the years before the early psychosurgical attempts. This article reviews the functional organization of the hypothalamus, the effects of ablation and stimulation of discrete hypothalamic regions, and the stereotactic targets that have most often been used in the treatment of psychopathological and behavioral symptoms; finally, the implications of current and past experience are presented from the perspective of how this fund of knowledge may usefully contribute to the future of hypothalamic psychosurgery.
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Hipotálamo/diagnóstico por imagem , Hipotálamo/cirurgia , Transtornos Mentais/diagnóstico por imagem , Transtornos Mentais/cirurgia , Procedimentos Neurocirúrgicos/métodos , Humanos , Técnicas EstereotáxicasRESUMO
The high-affinity calcium influx system (HACS) consisted of CaCch1, CaMid1 and CaEcm7 controls calcium influx into the cell in response to environmental stimuli. The plasma membrane protein CaRch1 is a negative regulator of calcium influx in Candida albicans. In this study, we show that deletion of any of the HACS components suppresses the calcium hypersensitivity of, and the elevated activation level of calcium/calcineurin signaling in, C. albicans cells lacking CaRCH1. In contrast, CaRCH1 is epistatic to the HACS system in the tolerance of antifungal drugs. In addition, cells lacking CaRCH1 are sensitive to tunicamycin, show a delay in in vitro filamentation and an altered colony surface morphology, and are attenuated in virulence in a mouse systemic model. Cells lacking CaCCH1 and CaMID1, but not CaECM7, are sensitive to tunicamycin. Deletion of CaRCH1 increases the tunicamycin sensitivity of cells lacking CaECM7 or CaMID1, but not CaCCH1. Furthermore, deletion of CaRCH1 suppresses the defect in hyphal development due to the deletion of CaCCH1 or CaECM7, and increases the virulence of cells lacking any of the HACS components. Therefore, CaRch1 genetically interacts with the HACS components in different fashions for these functions.
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Canais de Cálcio/metabolismo , Cálcio/metabolismo , Candida albicans/fisiologia , Regulação Fúngica da Expressão Gênica , Homeostase , Estresse Fisiológico , alfa Carioferinas/metabolismo , Animais , Candida albicans/citologia , Candida albicans/genética , Candida albicans/metabolismo , Candidíase/microbiologia , Candidíase/patologia , Modelos Animais de Doenças , Tolerância a Medicamentos , Deleção de Genes , Camundongos , VirulênciaRESUMO
The Golgi-localized Saccharomyces cerevisiae ScGdt1 is a member of the cation/Ca(2+) exchanger superfamily. We show here that Candida albicans CaGdt1 is the functional homolog of ScGdt1 in calcium sensitivity, and shows genetic interactions with CaCch1 or CaMid1 in response to ER stresses. In addition, similar to ScCCH1 and ScMID1, deletion of either CaCCH1 or CaMID1 leads to a growth sensitivity of cells to cold stress, which can be suppressed by deletion of CaGDT1. Furthermore, deletion of CaCCH1 leads to a severe delay in filamentation of C. albicans cells, and this defect is abolished by deletion of CaGDT1. In contrast, CaGDT1 does not show genetic interaction with CaMID1 in filamentation. Interestingly, C. albicans cells lacking both CaMID1 and CaGDT1 exhibit an intermediate virulence between C. albicans cells lacking CaCCH1 (non-virulent) and C. albicans cells lacking CaGDT1 (partially virulent), while C. albicans cells lacking both CaCCH1 and CaGDT1 are not virulent in a mouse model of systemic candidiasis. Therefore, CaGdt1 genetically interacts with the plasma membrane calcium channel, CaCch1/CaMid1, in the response of C. albicans cells to cold and ER stresses and antifungal drug challenge as well as in filamentation and virulence.
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Canais de Cálcio/metabolismo , Cálcio/metabolismo , Candida albicans/fisiologia , Regulação Fúngica da Expressão Gênica , Complexo de Golgi/enzimologia , Homeostase , Estresse Fisiológico , Animais , Antifúngicos/metabolismo , Candida albicans/citologia , Candida albicans/genética , Candida albicans/metabolismo , Candidíase/microbiologia , Candidíase/patologia , Temperatura Baixa , Modelos Animais de Doenças , Deleção de Genes , Camundongos , Mapeamento de Interação de Proteínas , VirulênciaRESUMO
PURPOSE: To assess the safety and efficacy of 2 concurrent injections of collagenase clostridium histolyticum (CCH) in the same hand to treat multiple Dupuytren flexion contractures. METHODS: In a multicenter, open-label phase IIIb study, 60 patients received two 0.58-mg CCH doses injected into cords affecting 2 joints in the same hand during 1 visit, followed by finger extension approximately 24 hours later. Efficacy at postinjection day 30 (change in flexion contracture and active range of motion, patient satisfaction, physician-rated improvement, and rates of clinical success [flexion contracture 5° or less]) and adverse events were summarized. RESULTS: The concurrent injections were most commonly administered in cords affecting metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints on the same finger (47%) or 2 MCP joints on different fingers of the same hand (37%). Mean total (sum of the 2 treated joints) flexion contracture decreased 76%, from 87° to 24° (MCP joints: 86%; PIP joints: 66%). Mean total range of motion increased from 100° to 161°. Clinical success was 76% for MCP joints and 33% for PIP joints. Most patients were very satisfied (60%) or quite satisfied (28%) with treatment. Most investigators rated treated joints as very much improved (55%) or much improved (37%). The most common treatment-related adverse events (> 75% of patients) were contusion, pain in extremity, and edema peripheral (local edema). Most adverse events were mild to moderate in severity. Serious complications included 1 pulley rupture related to study medication and 1 flexor tendon rupture (following conclusion of the study). There were no systemic complications. CONCLUSIONS: Results suggest that 2 affected joints can be effectively and safely treated with concurrent CCH injections. There was an increased incidence of some adverse events with concurrent treatment (pruritus, lymphadenopathy, blood blister, and skin laceration) compared with treatment of a single joint. High degrees of patient satisfaction and physician-rated improvement were reported. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.
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Contratura de Dupuytren/tratamento farmacológico , Colagenase Microbiana/administração & dosagem , Idoso , Contratura de Dupuytren/fisiopatologia , Feminino , Articulações dos Dedos/efeitos dos fármacos , Articulações dos Dedos/fisiopatologia , Humanos , Injeções Intralesionais , Masculino , Articulação Metacarpofalângica/efeitos dos fármacos , Articulação Metacarpofalângica/fisiopatologia , Colagenase Microbiana/efeitos adversos , Pessoa de Meia-Idade , Amplitude de Movimento Articular/efeitos dos fármacos , Amplitude de Movimento Articular/fisiologia , RetratamentoRESUMO
PURPOSE: The FNA-CT is useful for the diagnosis of MTC. The aim of this study was to evaluate the performance of FNA-CT in TNs coexisting with CCH. METHODS: This study retrospectively reviewed the records of 11 patients with TNs submitted to thyroidectomy on the basis of elevated basal and/or stimulated serum CT values, which at histology were not confirmed to be MTC. The results obtained in this group were compared with those of a previously reported group of histologically proven MTC patients submitted to an identical presurgical evaluation. All patients, negative for known mutations in the RET proto-oncogene, were preoperatively submitted to neck ultrasound, FNA-cytology, and FNA-CT. RESULTS: Approximately 6 of 11 patients showed increased (>36 ng/mL, as established in previous studies not involving patients with CCH) FNA-CT. All these patients showed diffuse CCH at histology in the thyroid lobe submitted to FNA; 5 of them were benign at histology, while only one was malignant (papillary thyroid carcinoma, PTC). The remaining 5 of 11 patients had low FNA-CT (<36 ng/mL), and all of them showed only focal CCH in the lobe submitted to FNA; three of them were malignant (2 PTC, 1 follicular carcinoma), while two were benign. CONCLUSIONS: Employing the currently proposed cut-off values, false-positive FNA-CT results may be observed in benign/malignant TNs with coexisting diffuse CCH. FNA-CT must therefore be cautiously used in the diagnostic approach for patients with TNs and a slightly increased basal or stimulated serum CT concentration in order to avoid unnecessary surgery.
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AIM: Efficient synthesis of precursor from commercially available starting materials and automated radiosynthesis of [11C]PiB using commercially available dedicated [11C]- Chemistry module from the synthesized precursor. BACKGROUND: [11C]PiB is a promising radiotracer for PET imaging of ß-Amyloid, advancing Alzheimer's disease research. The availability of precursors and protocols for efficient radiolabelling foster the applications of any radiotracer. Efficient synthesis of PiB precursor was performed using anisidine and 4-nitrobenzoyl chloride as starting materials in 5 steps, having addition, substitutions, and cyclization chemical methodologies. This precursor was used for fully automated radiosynthesis of [11C]PiB in a commercially available synthesizer, MPS-100 (SHI, Japan). The synthesized [11C]PiB was purified via solid-phase methodology, and its quality control was performed by the quality and safety criteria required for clinical use. METHODS: The synthesis of desired precursors and standard authentic compounds started with commercially available materials with 70-80% yields. The standard analytical methods were characterized all synthesized compounds. The fully automated [11C]-chemistry synthesizer (MPS-100) used for radiosynthesis of [11C]PiB with [11C]CH3OTf acts as a methylating agent. For radiolabelling, varied amounts of precursor and time of reaction were explored. The resulting crude product underwent purification through solid-phase cartridges. The synthesized radiotracer was analyzed using analytical tools such as radio TLC, HPLC, pH endo-toxicity, and half-life. RESULTS: The precursor for radiosynthesis of [11C]PiB was achieved in excellent yield using simple and feasible chemistry. A protocol for radiolabelling of precursor to synthesized [11C]PiB was developed using an automated synthesizer. The crude radiotracer was purified by solid-phase cartridge, with a decay-corrected radiochemical yield of 40±5% and radiochemical purity of more than 97% in approx 20 minutes (EOB). The specific activity was calculated and found in a 110-121 mCi/µmol range. CONCLUSION: A reliable methodology was developed for preparing precursor followed by fully automated radiolabeling using [11C]MeOTf as a methylating agent to synthesize [11C]PiB. The final HPLC-free purification yielded more than 97% radiochemical purity tracer within one radionuclide half-life. The method was reproducible and efficient for any clinical center.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Compostos de Anilina , Radioisótopos de Carbono , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Tiazóis , Compostos Radiofarmacêuticos/síntese química , Compostos de Anilina/síntese química , Compostos de Anilina/química , Tomografia por Emissão de Pósitrons/métodos , Tiazóis/síntese química , Tiazóis/química , Radioisótopos de Carbono/química , Doença de Alzheimer/diagnóstico por imagem , Humanos , Automação , Benzotiazóis/síntese química , Benzotiazóis/químicaRESUMO
Vascular cognitive impairment (VCI) is a syndrome defined as cognitive decline caused by vascular disease and is associated with various types of dementia. Chronic cerebral hypoperfusion (CCH) is one of the major contributors to VCI. Among the various rodent models used to study CCH-induced VCI, we have found the mouse bilateral common carotid artery stenosis (BCAS) model to be highly suitable. Here, we introduce the BCAS model of C57BL/6J mice generated using microcoils with an internal diameter of 0.18 mm. To produce the mouse BCAS model, the bilateral common carotid arteries are isolated from the adhering tissues and vagus nerves and twined around the microcoils. This model shows cognitive impairment and white matter lesions preceding neuronal dysfunction around postoperative day 28, which is similar to the human clinical picture. Overall, the mouse BCAS model will continue to be useful in studying CCH-induced VCI. Key features ⢠This mouse BCAS model requires approximately 4 weeks to show phenotypes such as cognitive impairment and white matter injury.
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CONTEXT: Central congenital hypothyroidism (CCH) is a thyroid hormone deficiency at birth caused by inadequate pituitary stimulation of the thyroid gland. Although primary CH has been studied extensively, studies on CCH are sparse. OBJECTIVES: To assess the prevalence of CCH in Israel and describe its clinical features, neonatal screening results, and outcomes. DESIGN: Multicenter cross-sectional retrospective chart review. SETTING: Nine pediatric endocrine units throughout Israel. PATIENTS: Patients diagnosed with CCH in 1987-2021 were categorized into early (within 14 days of life) and late (after 14 days) diagnosis groups. Newborn screening (NBS) results were retrospectively retrieved from the national NBS program dataset. RESULTS: CCH prevalence in Israel was about 1:42,800 live births. Subjects were 94 patients (54 males), of these, 84% had multiple pituitary hormone deficiencies and 16% had isolated CCH. The median age at diagnosis was 50 days (range, 1-8760), with 66% having moderate to severe hypothyroidism. NBS detected only three infants. Early diagnosis occurred in 34% due to hypopituitarism, while 66% were diagnosed later due to growth and developmental delays. Neurodevelopmental sequelae included mental retardation (12%), learning difficulties (18%), delayed speech (27%), and motor clumsiness (19%), with no significant differences in outcomes between early and late diagnosis. CONCLUSIONS: Despite high rates of neurodevelopmental sequelae, no differences were found between early and late diagnosis groups. Further research is needed to assess the impact of delayed diagnosis on neurological outcomes in newborns with CCH. Improved strategies for detecting CHH in newborns are also necessary.
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Shortened action-potential duration (APD) and blunted APD rate adaptation are hallmarks of chronic atrial fibrillation (cAF). Basal and muscarinic (M)-receptor-activated inward-rectifier K(+) currents (IK1 and IK,ACh, respectively) contribute to regulation of human atrial APD and are subject to cAF-dependent remodeling. Intracellular Na(+) ([Na(+)]i) enhances IK,ACh in experimental models but the effect of [Na(+)]i-dependent regulation of inward-rectifier K(+) currents on APD in human atrial myocytes is currently unknown. Here, we report a [Na(+)]i-dependent inhibition of outward IK1 in atrial myocytes from sinus rhythm (SR) or cAF patients. In contrast, IK,ACh activated by carbachol, a non-selective M-receptor agonist, increased with elevation of [Na(+)]i in SR. This [Na(+)]i-dependent IK,ACh regulation was absent in cAF. Including [Na(+)]i dependence of IK1 and IK,ACh in a recent computational model of the human atrial myocyte revealed that [Na(+)]i accumulation at fast rates inhibits IK1 and blunts physiological APD rate dependence in both groups. [Na(+)]i-dependent IK,ACh augmentation at fast rates increased APD rate dependence in SR, but not in cAF. These results identify impaired Na(+)-sensitivity of IK,ACh as one potential mechanism contributing to the blunted APD rate dependence in patients with cAF. This article is part of a Special Issue entitled "Na(+) Regulation in Cardiac Myocytes".
Assuntos
Acetilcolina/farmacologia , Potenciais de Ação , Fibrilação Atrial/fisiopatologia , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Agonistas Muscarínicos/farmacologia , Idoso , Arritmia Sinusal/metabolismo , Arritmia Sinusal/fisiopatologia , Fibrilação Atrial/metabolismo , Carbacol/farmacologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Técnicas de Patch-Clamp , Subunidades Proteicas/metabolismo , Sódio/metabolismoRESUMO
Atrial tachyarrhythmias, the most common type of cardiac arrhythmias, are associated with greater stroke risk. Muscarinic cholinergic agonists have been shown to facilitate atrial tachyarrhythmia maintenance in the absence of cardiac disease. This has been attributed to action potential shortening, which enhances myocardial electrical anisotropy, and thus creates a substrate for reentrant excitation. In this study, we describe a similar effect of the ATP-sensitive K(+) channel (KATP) opener pinacidil on tachyarrhythmia induction in isolated rat atria. Pinacidil, which activates a weakly inwardly-rectifying current in isolated atrial myocytes, enhanced arrhythmia induction in the right and left atria. This effect was abolished by the KATP blocker glibenclamide, but not by atropine, which rules out a possible indirect effect due to stimulation of acetylcholine release. However, pinacidil attenuated carbachol-induced tachyarrhythmia facilitation, which may indicate that the action of these agonists converges to a common cellular mechanism. Both agonists caused marked action potential shortening in isolated atrial myocytes. Moreover, during arrhythmia in the presence of pinacidil and carbachol, the atrial vectorelectrographic patterns were similar and consistent with reentrant propagation of the electrical activity. From these results, we conclude that the KATP channel opening is pro-arrhythmic in atrial tissue, which may pose as an additional risk in the scenario of myocardial hypoxia. Moreover, the similarity of the electrophysiological effects of pinacidil and carbachol is suggestive that the sole increase in background K(+) conductance is sufficient for atrial tachyarrhythmia facilitation.
Assuntos
Átrios do Coração/efeitos dos fármacos , Átrios do Coração/fisiopatologia , Agonistas Muscarínicos/farmacologia , Pinacidil/farmacologia , Taquicardia/fisiopatologia , Potenciais de Ação/efeitos dos fármacos , Animais , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Técnicas In Vitro , Masculino , Ratos , Ratos Wistar , Nó Sinoatrial/efeitos dos fármacos , Nó Sinoatrial/patologia , Nó Sinoatrial/fisiopatologia , Taquicardia/diagnóstico por imagem , Taquicardia/patologia , UltrassonografiaRESUMO
The present study was aimed at establishing a link between the cholinergic system and the pathway of mTOR and its downstream effector p70S6K, likely actors in long term memory encoding. We performed in vivo behavioral experiments using the step down inhibitory avoidance test (IA) in adult Wistar rats to evaluate memory formation under different conditions, and immunohistochemistry on hippocampal slices to evaluate the level and the time-course of mTOR and p70S6K activation. We also examined the effect of RAPA, inhibitor of mTORC1 formation, and of the acetylcholine (ACh) muscarinic receptor antagonist scopolamine (SCOP) or ACh nicotinic receptor antagonist mecamylamine (MECA) on short and long term memory formation and on the functionality of the mTOR pathway. Acquisition test was performed 30 min after i.c.v. injection of RAPA, a time sufficient for the drug to diffuse to CA1 pyramidal neurons, as demonstrated by MALDI-TOF-TOF imaging. Recall test was performed 1 h, 4 h or 24 h after acquisition. To confirm our results we performed in vitro experiments on live hippocampal slices: we evaluated whether stimulation of the cholinergic system with the cholinergic receptor agonist carbachol (CCh) activated the mTOR pathway and whether the administration of the above-mentioned antagonists together with CCh could revert this activation. We found that (1) mTOR and p70S6K activation in the hippocampus were involved in long term memory formation; (2) RAPA administration caused inhibition of mTOR activation at 1 h and 4 h and of p70S6K activation at 4 h, and long term memory impairment at 24 h after acquisition; (3) scopolamine treatment caused short but not long term memory impairment with an early increase of mTOR/p70S6K activation at 1 h followed by stabilization at longer times; (4) mecamylamine plus scopolamine treatment caused short term memory impairment at 1 h and 4 h and reduced the scopolamine-induced increase of mTOR/p70S6K activation at 1 h and 4 h; (5) mecamylamine plus scopolamine treatment did not impair long term memory formation; (6) in vitro treatment with carbachol activated mTOR and p70S6K and this effect was blocked by scopolamine and mecamylamine. Taken together our data reinforce the idea that distinct molecular mechanisms are at the basis of the two different forms of memory and are in accordance with data presented by other groups that there exist molecular mechanisms that underlie short term memory, others that underlie long term memories, but some mechanisms are involved in both.
Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Memória de Longo Prazo/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Receptores Muscarínicos/metabolismo , Receptores Nicotínicos/metabolismo , Animais , Aprendizagem da Esquiva/fisiologia , Hipocampo/metabolismo , Masculino , Mecamilamina/farmacologia , Memória de Longo Prazo/fisiologia , Memória de Curto Prazo/efeitos dos fármacos , Memória de Curto Prazo/fisiologia , Antagonistas Muscarínicos/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Antagonistas Nicotínicos/farmacologia , Biossíntese de Proteínas/fisiologia , Ratos , Ratos Wistar , Escopolamina/farmacologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
Male urethral stricture disease is highly prevalent and difficult to treat due to potential complications. Minimally invasive treatments tend to have high recurrence rates, keeping urethroplasty as the gold standard. Collagenase Clostridium histolyticum (CCH) has been used in humans to treat fibrosis in a minimally invasive manner. Herein, we present the preliminary results from treatments of three males with urethral stricture as a feasibility and safety evaluation of the first-in-human CCH treatment for male urethral stricture disease.