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1.
Am J Dermatopathol ; 46(7): 416-432, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648027

RESUMO

AIMS: Cutaneous follicular (infundibular-tricholemmal) squamous cell carcinoma (FSCC) is a new World Health Organization entity. We present the largest series of published cases, summarizing clinical data, diagnostic criteria, differential diagnosis, and implications for patient management. METHODS: Cases were identified from 2004 to 2011. Inclusion criteria included discrete attachment(s) of the tumor to the overlying epidermis via follicular infundibula, tricholemmal keratinization, and cellular pleomorphism. Keratoacanthoma and lesions with adjacent bowenoid epidermal dysplasia were excluded. RESULTS: One hundred three cases of FSCC identified. 48.5% demonstrated completely circumscript borders ( in situ for practical purposes), 12.6% uncertain for invasion (overwhelmingly pushing borders), and only 38.8% as clearly invasive. Follicular mucin in acantholytic spaces within tumor epithelium was a distinctive finding in 57.2% of cases. Clinical data indicated predominance in elderly (median 78.5 years) men (70.4%), with preferential head and neck location (81.6%). Many were clinically suspected as squamous cell carcinoma (48.5%). However, a significant minority were clinically diagnosed as basal cell carcinoma (40.8%). This may reflect that FSCC commonly presented as a papule or nodule (51.3%). By contrast, keratoacanthoma was less frequently suggested (17.2%) and still fewer lesions were suspected to be actinic keratosis/Bowen's disease (13.6%). Follow-up in 82 cases (median 26.5 months, range 3-144) identified 5 (6.1%) local recurrences. There was no instance of metastasis in the subgroup of lesions with completely circumscript borders. Three of 45 (6.7%) patients, with follow-up, considered to have tumors with invasive pushing, and/or infiltrative borders developed lymph node metastases. CONCLUSIONS: FSCC is identified as a common skin cancer, incorporating historical entities, such as infundibular carcinoma and tricholemmal carcinoma, with readily identifiable histologic features. Correct diagnosis has implications for patient management; a significant subgroup of lesions show completely circumscript borders that are considered in situ for practical purposes.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Masculino , Idoso , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas/patologia , Feminino , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Adulto , Folículo Piloso/patologia
2.
Cardiovasc Diabetol ; 21(1): 50, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395808

RESUMO

The 7th Cardiovascular Outcome Trial (CVOT) Summit on Cardiovascular, Renal, and Glycemic Outcomes, was held virtually on November 18-19, 2021. Pursuing the tradition of the previous summits, this reference congress served as a platform for in-depth discussion and exchange on recently completed CVOTs. This year's focus was placed on the outcomes of EMPEROR-Preserved, FIGARO-DKD, AMPLITUDE-O, SURPASS 1-5, and STEP 1-5. Trial implications for diabetes and obesity management and the impact on new treatment algorithms were highlighted for endocrinologists, diabetologists, cardiologists, nephrologists, and general practitioners. Discussions evolved from outcome trials using SGLT2 inhibitors as therapy for heart failure, to CVOTs with nonsteroidal mineralocorticoid receptor antagonists and GLP-1 receptor agonists. Furthermore, trials for glycemic and overweight/obesity management, challenges in diabetes management in COVID-19, and novel guidelines and treatment strategies were discussed.Trial registration The 8th Cardiovascular Outcome Trial Summit will be held virtually on November 10-11, 2022 ( http://www.cvot.org ).


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Glicemia , COVID-19 , Doenças Cardiovasculares/tratamento farmacológico , Ensaios Clínicos como Assunto , Diabetes Mellitus/tratamento farmacológico , Humanos , Hipoglicemiantes/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Resultado do Tratamento
3.
J Physiol ; 599(17): 4065-4084, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34174096

RESUMO

KEY POINTS: GABA depolarized sural nerve axons and increased the electrical excitability of C-fibres via GABAA receptor. Axonal excitability responses to GABA increased monotonically with the rate of action potential firing. Action potential activity in unmyelinated C-fibres is coupled to Na-K-Cl cotransporter type 1 (NKCC1) loading of axonal chloride. Activation of axonal GABAA receptor stabilized C-fibre excitability during prolonged low frequency (2.5 Hz) firing. NKCC1 maintains intra-axonal chloride to provide feed-forward stabilization of C-fibre excitability and thus support sustained firing. ABSTRACT: GABAA receptor (GABAA R)-mediated depolarization of dorsal root ganglia (DRG) axonal projections in the spinal dorsal horn is implicated in pre-synaptic inhibition. Inhibition, in this case, is predicated on an elevated intra-axonal chloride concentration and a depolarizing GABA response. In the present study, we report that the peripheral axons of DRG neurons are also depolarized by GABA and this results in an increase in the electrical excitability of unmyelinated C-fibre axons. GABAA R agonists increased axonal excitability, whereas GABA excitability responses were blocked by GABAA R antagonists and were absent in mice lacking the GABAA R ß3 subunit selectively in DRG neurons (AdvillinCre or snsCre ). Under control conditions, excitability responses to GABA became larger at higher rates of electrical stimulation (0.5-2.5 Hz). However, during Na-K-Cl cotransporter type 1 (NKCC1) blockade, the electrical stimulation rate did not affect GABA response size, suggesting that NKCC1 regulation of axonal chloride is coupled to action potential firing. To examine this, activity-dependent conduction velocity slowing (activity-dependent slowing; ADS) was used to quantify C-fibre excitability loss during a 2.5 Hz challenge. ADS was reduced by GABAA R agonists and exacerbated by either GABAA R antagonists, ß3 deletion or NKCC1 blockade. This illustrates that activation of GABAA R stabilizes C-fibre excitability during sustained firing. We posit that NKCC1 acts in a feed-forward manner to maintain an elevated intra-axonal chloride in C-fibres during ongoing firing. The resulting chloride gradient can be utilized by GABAA R to stabilize axonal excitability. The data imply that therapeutic strategies targeting axonal chloride regulation at peripheral loci of pain and itch may curtail aberrant firing in C-fibres.


Assuntos
Axônios , Fibras Nervosas Amielínicas , Animais , Camundongos , Membro 2 da Família 12 de Carreador de Soluto , Membro 3 da Família 12 de Carreador de Soluto , Simportadores , Ácido gama-Aminobutírico , Cotransportadores de K e Cl-
4.
Histopathology ; 79(5): 810-825, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34121219

RESUMO

AIMS: Superficial CD34-positive fibroblastic tumor (SCD34FT) and PRDM10-rearranged soft tissue tumor (PRDM10-STT) are rare mesenchymal tumors. These lesions have clinicopathological similarities, but their relationship remains controversial. This study aimed to characterise a series of cases of SCD34FT and PRDM10-STT. METHODS AND RESULTS: Ten lesions each of SCD34FT and PRDM10-STT were studied using immunohistochemistry, array-comparative genomic hybridisation (aCGH), RNA sequencing and exome sequencing. Tumors mainly occurred in young adults, were generally small (< 5 cm) and arose predominantly in the superficial soft tissues of the lower extremities. Follow-up data were available in 15 cases (SCD34FT, n = 7, median 16 months; PRDM10-STT, n = 8, median 14 months), local recurrences occurred in four cases (SCD34FT, two of 10; PRDM10-STT, two of 10), while no distant spread was documented. Morphologically, tumors were relatively well-circumscribed and composed of sheets and fascicles of spindle and pleomorphic cells showing low mitotic activity (< 1/mm²) without necrosis. Other findings included: granular cell change, lipoblast-like cells, ectatic blood vessels with fibrinous material, myxoid stromal changes, metaplastic bone and increased mitotic activity (> 1/mm²). All tumors diffusely expressed CD34, while pan-keratin and desmin were commonly seen focally. SynCAM3 was diffusely expressed in 12 cases (SCD34FT, n = 5; PRDM10-STT, n = 7), independently of fusion status. aCGH profiles were 'flat' (PRDM10-STT, n = 4; SCD34FT, n = 2) and exome sequencing showed no recurrent pathogenic mutations (PRDM10-STT, n = 2; SCD34FT, n = 4). Overall, the only morphological features seen exclusively in PRDM10-STT were myxoid stromal changes (three of 10) and metaplastic bone (two of 10). CONCLUSION: We expand the current knowledge on PRDM10-STT and SCD34FT and provide additional evidence for considering them as overlapping entities.


Assuntos
Antígenos CD34/metabolismo , Proteínas de Ligação a DNA , Fibroblastos/patologia , Neoplasias de Tecidos Moles , Fatores de Transcrição , Adolescente , Adulto , Biomarcadores Tumorais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Rearranjo Gênico , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/metabolismo , Neoplasias de Tecidos Moles/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Adulto Jovem
5.
Artigo em Inglês | MEDLINE | ID: mdl-33719361

RESUMO

BACKGROUND: It has been proposed that autistic individuals are at an increased risk of type 1 and type 2 diabetes. Improved understanding of diabetes prevalence in autistic persons will help inform resource allocation for diabetes-related public health measures for this patient group. OBJECTIVE: To conduct a systematic review of published literature pertaining to type 1 and type 2 diabetes prevalence in autistic individuals, including comparison with their non-autistic peers. METHODS: Eligibility criteria included studies investigating the prevalence of diabetes in autistic individuals, as well as having been published in the English language. A systematic search of online databases (MEDLINE, PsycINFO, CINAHL, EMBASE and PubMed) was conducted on 4th April 2020. Additional approaches included the ancestry method, grey literature searches and expert consultation. Studies were qualitatively analysed with reporting quality appraised. RESULTS: 19 eligible studies were identified, 7 of which provided type-specific diabetes prevalence data. Of 15 studies that included a non-autistic control group, 9 reported a higher diabetes prevalence among autistic persons, with a statistically significant difference in 4 studies. Studies demonstrating a higher diabetes prevalence in autistic groups had higher average study population sizes and reporting quality ratings. CONCLUSION: It is uncertain whether diabetes is significantly more prevalent in autistic persons relative to their non-autistic peers, though larger studies suggest a trend in this direction. Nevertheless, diabetes is a significant public health issue for the autistic community, which may require a tailored approach for identification and management. Prospero database registration number: CRD42019122176.

6.
Cell Tissue Res ; 375(1): 217-225, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30377783

RESUMO

Peptides released from trigeminal fibers fulfill well-understood functions in neuroinflammatory processes and in the modulation of nociceptive signal processing. In particular, calcitonin gene-related peptide (CGRP) and substance P (SP), released from afferent nerve terminals, exert paracrine effects on the surrounding tissue and this has been recently highlighted by the prominent parcrine role of CGRP in the development of headache and migraine. Some recent communications suggest that these sensory neuropeptides may also modulate the workings of sensory organs and influence afferent signals from nose, tongue, eyes and ears. Here, we briefly review the evidence for modulatory effects of CGRP and SP in the sensory periphery.


Assuntos
Neuropeptídeos/metabolismo , Sensação/fisiologia , Animais , Humanos , Modelos Biológicos , Percepção
7.
Ann Neurol ; 83(5): 945-957, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29659054

RESUMO

OBJECTIVE: Develop and validate a low-intensity sinusoidal electrical stimulation paradigm to preferentially activate C-fibers in human skin. METHODS: Sinusoidal transcutaneous stimulation (4Hz) was assessed psychophysically in healthy volunteers (n = 14) and neuropathic pain patients (n = 9). Pursuing laser Doppler imaging and single nociceptor recordings in vivo in humans (microneurography) and pigs confirmed the activation of "silent" C-nociceptors. Synchronized C-fiber compound action potentials were evoked in isolated human nerve fascicles in vitro. Live cell imaging of L4 dorsal root ganglia in anesthetized mice verified the recruitment of small-diameter neurons during transcutaneous 4-Hz stimulation of the hindpaw (0.4mA). RESULTS: Transcutaneous sinusoidal current (0.05-0.4mA, 4Hz) activated "polymodal" C-fibers (50% at ∼0.03mA) and "silent" nociceptors (50% at ∼0.04mA), intensities substantially lower than that required with transcutaneous 1-ms rectangular pulses ("polymodal" ∼3mA, "silent" ∼50mA). The stimulation induced delayed burning (nonpulsating) pain and a pronounced axon-reflex erythema, both indicative of C-nociceptor activation. Pain ratings to repetitive stimulation (1 minute, 4Hz) adapted in healthy volunteers by Numeric Rating Scale (NRS) -3 and nonpainful skin sites of neuropathic pain patients by NRS -0.5, whereas pain even increased in painful neuropathic skin by approximately NRS +2. INTERPRETATION: Sinusoidal electrical stimulation at 4Hz enables preferential activation of C-nociceptors in pig and human skin that accommodates during ongoing (1-minute) stimulation. Absence of such accommodation in neuropathic pain patients suggest axonal hyperexcitability that could be predictive of alterations in peripheral nociceptor encoding and offer a potential therapeutic entry point for topical analgesic treatment. Ann Neurol 2018;83:945-957.


Assuntos
Axônios/fisiologia , Neuralgia/fisiopatologia , Nociceptores/fisiologia , Dor/fisiopatologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Adulto , Animais , Dor Crônica/fisiopatologia , Estimulação Elétrica/métodos , Gânglios Espinais/fisiopatologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Limiar da Dor/fisiologia , Pele/inervação
8.
J Am Acad Dermatol ; 81(6): 1257-1270, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30930084

RESUMO

BACKGROUND: We present a distinctive type of acquired vascular proliferation, for which we propose the name of poikilodermatous plaque-like hemangioma. OBJECTIVE: The aim of this study was to summarize the clinical and histopathologic features in a case series of poikilodermatous plaque-like hemangioma. METHODS: Sixteen cases were identified from the routine clinical and referral practices of the authors. Clinical characteristics, including demographic details and clinical morphology, were collated. The salient histopathologic features, including immunohistochemical staining results, were summarized. RESULTS: The lesions were usually solitary erythematous-to-violaceous poikilodermatous plaques on the lower extremities and pelvic girdle, with an indolent clinical course. Mean age of affected patients was 72 (range 58-80) years, and there was a male predominance. Histology comprised a distinctive band-like proliferation of vascular channels suggestive of postcapillary venules within the superficial dermis with a background of fibrosis, edema, and loss of elastic fibers. Despite the clinical atrophic appearance, acanthosis was a frequent finding. LIMITATIONS: Retrospective study. CONCLUSION: Poikilodermatous plaque-like hemangioma is a distinctive and previously undescribed vascular proliferation defined by a constellation of consistent and reproducible clinical and histologic features.


Assuntos
Acrodermatite/patologia , Hemangioma/patologia , Ceratose/patologia , Neoplasias Cutâneas/patologia , Acrodermatite/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Tomada de Decisão Clínica , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Hemangioma/diagnóstico , Humanos , Imuno-Histoquímica , Ceratose/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico
9.
Proc Natl Acad Sci U S A ; 113(28): E4107-16, 2016 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-27354517

RESUMO

ß-adrenergic receptors (ßARs) are critical regulators of acute cardiovascular physiology. In response to elevated catecholamine stimulation during development of congestive heart failure (CHF), chronic activation of Gs-dependent ß1AR and Gi-dependent ß2AR pathways leads to enhanced cardiomyocyte death, reduced ß1AR expression, and decreased inotropic reserve. ß-blockers act to block excessive catecholamine stimulation of ßARs to decrease cellular apoptotic signaling and normalize ß1AR expression and inotropy. Whereas these actions reduce cardiac remodeling and mortality outcomes, the effects are not sustained. Converse to G-protein-dependent signaling, ß-arrestin-dependent signaling promotes cardiomyocyte survival. Given that ß2AR expression is unaltered in CHF, a ß-arrestin-biased agonist that operates through the ß2AR represents a potentially useful therapeutic approach. Carvedilol, a currently prescribed nonselective ß-blocker, has been classified as a ß-arrestin-biased agonist that can inhibit basal signaling from ßARs and also stimulate cell survival signaling pathways. To understand the relative contribution of ß-arrestin bias to the efficacy of select ß-blockers, a specific ß-arrestin-biased pepducin for the ß2AR, intracellular loop (ICL)1-9, was used to decouple ß-arrestin-biased signaling from occupation of the orthosteric ligand-binding pocket. With similar efficacy to carvedilol, ICL1-9 was able to promote ß2AR phosphorylation, ß-arrestin recruitment, ß2AR internalization, and ß-arrestin-biased signaling. Interestingly, ICL1-9 was also able to induce ß2AR- and ß-arrestin-dependent and Ca(2+)-independent contractility in primary adult murine cardiomyocytes, whereas carvedilol had no efficacy. Thus, ICL1-9 is an effective tool to access a pharmacological profile stimulating cardioprotective signaling and inotropic effects through the ß2AR and serves as a model for the next generation of cardiovascular drug development.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Carbazóis/farmacologia , Insuficiência Cardíaca/tratamento farmacológico , Lipopeptídeos/farmacologia , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Propanolaminas/farmacologia , Antagonistas Adrenérgicos beta/uso terapêutico , Animais , Carbazóis/uso terapêutico , Carvedilol , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Humanos , Lipopeptídeos/uso terapêutico , Camundongos , Cultura Primária de Células , Propanolaminas/uso terapêutico , Conformação Proteica/efeitos dos fármacos , beta-Arrestinas/agonistas
10.
J Neurosci ; 37(20): 5204-5214, 2017 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-28450535

RESUMO

Voltage-gated sodium (NaV) channels are responsible for the initiation and conduction of action potentials within primary afferents. The nine NaV channel isoforms recognized in mammals are often functionally divided into tetrodotoxin (TTX)-sensitive (TTX-s) channels (NaV1.1-NaV1.4, NaV1.6-NaV1.7) that are blocked by nanomolar concentrations and TTX-resistant (TTX-r) channels (NaV1.8 and NaV1.9) inhibited by millimolar concentrations, with NaV1.5 having an intermediate toxin sensitivity. For small-diameter primary afferent neurons, it is unclear to what extent different NaV channel isoforms are distributed along the peripheral and central branches of their bifurcated axons. To determine the relative contribution of TTX-s and TTX-r channels to action potential conduction in different axonal compartments, we investigated the effects of TTX on C-fiber-mediated compound action potentials (C-CAPs) of proximal and distal peripheral nerve segments and dorsal roots from mice and pigtail monkeys (Macaca nemestrina). In the dorsal roots and proximal peripheral nerves of mice and nonhuman primates, TTX reduced the C-CAP amplitude to 16% of the baseline. In contrast, >30% of the C-CAP was resistant to TTX in distal peripheral branches of monkeys and WT and NaV1.9-/- mice. In nerves from NaV1.8-/- mice, TTX-r C-CAPs could not be detected. These data indicate that NaV1.8 is the primary isoform underlying TTX-r conduction in distal axons of somatosensory C-fibers. Furthermore, there is a differential spatial distribution of NaV1.8 within C-fiber axons, being functionally more prominent in the most distal axons and terminal regions. The enrichment of NaV1.8 in distal axons may provide a useful target in the treatment of pain of peripheral origin.SIGNIFICANCE STATEMENT It is unclear whether individual sodium channel isoforms exert differential roles in action potential conduction along the axonal membrane of nociceptive, unmyelinated peripheral nerve fibers, but clarifying the role of sodium channel subtypes in different axonal segments may be useful for the development of novel analgesic strategies. Here, we provide evidence from mice and nonhuman primates that a substantial portion of the C-fiber compound action potential in distal peripheral nerves, but not proximal nerves or dorsal roots, is resistant to tetrodotoxin and that, in mice, this effect is mediated solely by voltage-gated sodium channel 1.8 (NaV1.8). The functional prominence of NaV1.8 within the axonal compartment immediately proximal to its termination may affect strategies targeting pain of peripheral origin.


Assuntos
Axônios/fisiologia , Canal de Sódio Disparado por Voltagem NAV1.8/fisiologia , Condução Nervosa/fisiologia , Nervos Periféricos/fisiologia , Pele/inervação , Tetrodotoxina/administração & dosagem , Vias Aferentes/efeitos dos fármacos , Vias Aferentes/fisiologia , Animais , Axônios/efeitos dos fármacos , Ativação do Canal Iônico/efeitos dos fármacos , Ativação do Canal Iônico/fisiologia , Macaca nemestrina , Masculino , Canal de Sódio Disparado por Voltagem NAV1.8/efeitos dos fármacos , Fibras Nervosas Amielínicas , Condução Nervosa/efeitos dos fármacos , Nervos Periféricos/efeitos dos fármacos , Pele/efeitos dos fármacos , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Bloqueadores do Canal de Sódio Disparado por Voltagem/administração & dosagem
11.
Basic Res Cardiol ; 113(6): 43, 2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30310998

RESUMO

Due to its poor capacity for regeneration, the heart is particularly sensitive to the loss of contractile cardiomyocytes. The onslaught of damage caused by ischaemia and reperfusion, occurring during an acute myocardial infarction and the subsequent reperfusion therapy, can wipe out upwards of a billion cardiomyocytes. A similar program of cell death can cause the irreversible loss of neurons in ischaemic stroke. Similar pathways of lethal cell injury can contribute to other pathologies such as left ventricular dysfunction and heart failure caused by cancer therapy. Consequently, strategies designed to protect the heart from lethal cell injury have the potential to be applicable across all three pathologies. The investigators meeting at the 10th Hatter Cardiovascular Institute workshop examined the parallels between ST-segment elevation myocardial infarction (STEMI), ischaemic stroke, and other pathologies that cause the loss of cardiomyocytes including cancer therapeutic cardiotoxicity. They examined the prospects for protection by remote ischaemic conditioning (RIC) in each scenario, and evaluated impasses and novel opportunities for cellular protection, with the future landscape for RIC in the clinical setting to be determined by the outcome of the large ERIC-PPCI/CONDI2 study. It was agreed that the way forward must include measures to improve experimental methodologies, such that they better reflect the clinical scenario and to judiciously select combinations of therapies targeting specific pathways of cellular death and injury.


Assuntos
Cardiologia , Oncologia , Infarto do Miocárdio , Acidente Vascular Cerebral , Animais , Antineoplásicos/efeitos adversos , Cardiologia/métodos , Cardiologia/tendências , Citoproteção , Humanos , Precondicionamento Isquêmico Miocárdico/métodos , Oncologia/métodos , Oncologia/tendências , Traumatismo por Reperfusão Miocárdica/prevenção & controle
12.
Diabetes Obes Metab ; 20(4): 1080-1085, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29227575

RESUMO

To explore the effects of a single dose of the DPP-4 inhibitor sitagliptin on glucose-standardized insulin secretion and ß-cell glucose sensitivity after meal ingestion, 12 healthy and 12 drug-naïve, well-controlled type 2 diabetes (T2D) subjects (mean HbA1c 43 mmol/mol, 6.2%) received sitagliptin (100 mg) or placebo before a meal (525 kcal). ß-cell function was measured as the insulin secretory rate at a standardized glucose concentration and the ß-cell glucose sensitivity (the slope between glucose and insulin secretory rate). Incretin levels were also monitored. Sitagliptin increased standardized insulin secretion, in both healthy and T2D subjects, compared to placebo, but without increasing ß-cell glucose sensitivity. Sitagliptin also increased active glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) and reduced total (reflecting the secretion) GIP, but not total GLP-1 levels. We conclude that a single dose of DPP-4 inhibition induces dissociated effects on different aspects of ß-cell function and incretin hormones after meal ingestion in both healthy and well-controlled T2D subjects.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/farmacologia , Incretinas/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Fosfato de Sitagliptina/farmacologia , Adulto , Idoso , Glicemia/efeitos dos fármacos , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/sangue , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/metabolismo , Secreção de Insulina , Masculino , Refeições/fisiologia , Pessoa de Meia-Idade , Período Pós-Prandial , Fosfato de Sitagliptina/administração & dosagem , Adulto Jovem
13.
Diabetes Obes Metab ; 20(1): 50-59, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28581253

RESUMO

AIMS: To analyse the prevalence of severe hypoglycaemia in patients with type 2 diabetes (T2DM) treated with antihyperglycaemic agents (AHA) and requiring emergency room (ER) assistance, and to analyse the prevalence according to type of AHA therapy. METHODS: The present study, the Hypoglycaemia In Portugal Observational Study-Emergency Room (HIPOS-ER), was a cross-sectional, observational, multicentre, nationwide study, with specific hypoglycaemia source data collection. RESULTS: Within the study period, a total of 425 706 admissions were recorded in the ERs of participating hospitals. The prevalence of severe hypoglycaemic episodes in patients with T2DM was 0.074%. In all, 238 patients were included, more than half of whom were on insulin-based therapy (55.0%) and a third of whom (31.5%) were on oral secretagogue-based therapy. In 61.2% of patients primary care was the main diabetes care setting. The median patient age was 77.5 years and the mean duration of diabetes was 19 years. Missing a meal or low carbohydrate meal content was the most frequent cause of hypoglycaemia (55.9%) and the most frequent triggers for seeking emergency assistance were pre-syncope (19.2%) and transient loss of consciousness (17.4%). A total of 44.1% of patients were hospitalized for a median of 5.1 days. Patients in the secretagogue group were admitted to hospital more often than patients in the insulin group (70.7% vs 29.0%; P < .001). Nine patients died. CONCLUSIONS: These findings confirm that severe hypoglycaemia in patients with T2DM requiring ER assistance occurs mainly in those on insulin- and secretagogue-based therapies and is associated with a significant medical burden. Antidiabetic therapy should be individualized to minimize the risk of severe iatrogenic hypoglycaemia, and any intervention to this end should always involve primary care stakeholders.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Incretinas/efeitos adversos , Insulina/efeitos adversos , Idoso , Terapia Combinada/efeitos adversos , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/mortalidade , Dieta para Diabéticos/efeitos adversos , Quimioterapia Combinada/efeitos adversos , Fenômenos Fisiológicos da Nutrição do Idoso/efeitos dos fármacos , Serviço Hospitalar de Emergência , Feminino , Humanos , Hipoglicemia/epidemiologia , Hipoglicemia/fisiopatologia , Hipoglicemia/terapia , Hipoglicemiantes/uso terapêutico , Incretinas/uso terapêutico , Insulina/metabolismo , Insulina/uso terapêutico , Secreção de Insulina , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Portugal/epidemiologia , Prevalência , Risco , Índice de Gravidade de Doença , Síncope/etiologia
15.
Am J Dermatopathol ; 40(8): 561-566, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29570129

RESUMO

Tricholemmoma, a benign follicular neoplasm with outer root sheath differentiation, typically comprises clear or pale cells, and when multiple is pathognomic of Cowden's syndrome. The tumor is probably underrecognized and in basaloid examples can be difficult to distinguish from basal cell carcinoma (BCC). We studied 55 tricholemmomas (including 15 basaloid cases) and compared immunohistochemical profile with nodular BCC from our archives. Basaloid and non-basaloid tricholemmomas had similar staining characteristics. BerEP4 was focally positive (range 10%-20%) in only 3/39 (7.7%) tricholemmomas compared with widespread positivity in BCC (90.8%, 139 of 151 cases with ≥50% tumor area stained). CD34 was expressed, usually focally (median 20%, range 10%-90%), in 52/53 (98.1%) tricholemmomas and was negative in all 21 BCCs stained. EMA staining lacked sensitivity or specificity in differentiating tricholemmoma from BCC. Five or more Merkel cells were found in 7/17 (40.1%) tricholemmomas and 1/23 (4.3%) nodular BCCs studied. In summary, immunohistochemistry is helpful in distinction between tricholemmoma, including difficult basaloid examples (BerEP4 negative or focal, CD34 positive) compared with BCC (BerEP4 widespread in most cases, CD34 negative). The presence of 5 or more Merkel cells is a relatively specific but not a particularly sensitive discriminator.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Basocelular/diagnóstico , Doenças do Cabelo/diagnóstico , Folículo Piloso/patologia , Neoplasias Cutâneas/diagnóstico , Antígenos CD34/análise , Antígenos CD34/biossíntese , Biomarcadores Tumorais/biossíntese , Diagnóstico Diferencial , Humanos
16.
J Pharmacol Exp Ther ; 362(2): 254-262, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28533287

RESUMO

Prescription opioids are a mainstay in the treatment of acute moderate to severe pain. However, chronic use leads to a host of adverse consequences including tolerance and opioid-induced hyperalgesia (OIH), leading to more complex treatment regimens and diminished patient compliance. Patients with OIH paradoxically experience exaggerated nociceptive responses instead of pain reduction after chronic opioid usage. The development of OIH and tolerance tend to occur simultaneously and, thus, present a challenge when studying the molecular mechanisms driving each phenomenon. We tested the hypothesis that a G protein-biased µ-opioid peptide receptor (MOPR) agonist would not induce symptoms of OIH, such as mechanical allodynia, following chronic administration. We observed that the development of opioid-induced mechanical allodynia (OIMA), a model of OIH, was absent in ß-arrestin1-/- and ß-arrestin2-/- mice in response to chronic administration of conventional opioids such as morphine, oxycodone and fentanyl, whereas tolerance developed independent of OIMA. In agreement with the ß-arrestin knockout mouse studies, chronic administration of TRV0109101, a G protein-biased MOPR ligand and structural analog of oliceridine, did not promote the development of OIMA but did result in drug tolerance. Interestingly, following induction of OIMA by morphine or fentanyl, TRV0109101 was able to rapidly reverse allodynia. These observations establish a role for ß-arrestins in the development of OIH, independent of tolerance, and suggest that the use of G protein-biased MOPR ligands, such as oliceridine and TRV0109101, may be an effective therapeutic avenue for managing chronic pain with reduced propensity for opioid-induced hyperalgesia.


Assuntos
Analgésicos Opioides/administração & dosagem , Proteínas de Ligação ao GTP/agonistas , Hiperalgesia/tratamento farmacológico , Medição da Dor/efeitos dos fármacos , Receptores Opioides mu/agonistas , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Proteínas de Ligação ao GTP/fisiologia , Células HEK293 , Humanos , Hiperalgesia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Medição da Dor/métodos , Receptores Opioides mu/fisiologia
18.
J Cutan Pathol ; 44(11): 954-957, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28796320

RESUMO

Cutaneous lymphadenoma is an uncommon benign neoplasm often considered to be an adamantinoid variant of trichoblastoma. Lesions present in both sexes, between 14 and 87 years of age, and are mainly located on the head and neck. Cases in children are rare and there is only 1 previous case of a congenital lymphadenoma. An 8-year-old Asian girl presented with a congenital lesion on her forehead comprising 4 pink papules, the largest 5 mm in diameter. Microscopy revealed a well-circumscribed tumor within the dermis and subcutis comprising well-demarcated epithelial lobules of basaloid and clear cells with subtle peripheral palisading, growing in a collagenous stroma but lacking retraction artefact. A relatively dense accompanying predominantly lymphocytic inflammatory cell infiltrate including both T-cells (CD3+) and B-cells (CD20+) permeated the nodules and spilled into the stroma. CD68+ histiocytes and CD1a+ Langerhans cells were moderately numerous. This is the second case of congenital lymphadenoma which-in spite of its rarity in childhood-widens the diagnostic possibilities of cutaneous lymphoepithelial tumors in children.


Assuntos
Doenças do Cabelo/congênito , Doenças do Cabelo/patologia , Folículo Piloso/patologia , Neoplasias Cutâneas/congênito , Neoplasias Cutâneas/patologia , Criança , Feminino , Humanos
19.
Subst Use Misuse ; 52(1): 1-9, 2017 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-27618694

RESUMO

BACKGROUND: An outgrowth of research has established a relationship between racial discrimination and alcohol use, as well as factors that moderate this association. OBJECTIVES: The main objective of this study was to determine if religious orientation moderates the relationship between perceived racial discrimination and alcohol use. METHODS: This study utilized a cross-sectional data collection strategy to examine the relationship among discrimination, religious orientation, and alcohol use among undergraduate students (N = 349) at a midsize southeastern university. Data was collected in 2014. Participants completed a demographic questionnaire, the General Ethnic Discrimination Scale, the Extrinsic/Intrinsic Religious Orientation Scale-Revised and the Drinking and Drug Habits Questionnaire. RESULTS: Analyses using hierarchical linear regression indicate a significant interaction effect (lifetime discrimination × extrinsic religious orientation) on problem drinking. Additional moderation analyses reveal a significant interaction effect between lifetime discrimination and the extrinsic-personal religious orientation on problem drinking. CONCLUSIONS: Results suggest that an extrinsic religious orientation, and particularly, an extrinsic-personal religious orientation, moderates the relationship between lifetime discrimination and problem drinking, suggesting that turning to religion for comfort and protection, rather than for the superficial purpose of seeing/making friends at church, may buffer against the deleterious effects of discrimination-specifically, engaging in problem drinking to cope with the stress of discrimination. Limitations, directions for future research, and clinical implications are discussed.


Assuntos
Adaptação Psicológica/fisiologia , Consumo de Bebidas Alcoólicas/psicologia , Racismo/psicologia , Religião , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários
20.
Mol Pharmacol ; 89(1): 94-104, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26464325

RESUMO

Gαqßγ heterotrimer (Gq), an important mediator in the pathology of airway disease, plays a central role in bronchoconstriction and airway remodeling, including airway smooth muscle growth and inflammation. Current therapeutic strategies to treat airway disease include the use of muscarinic and leukotriene receptor antagonists; however, these pharmaceuticals demonstrate a limited clinical efficacy as multiple Gq-coupled receptor subtypes contribute to these pathologies. Thus, broadly inhibiting the activation of Gq may be an advantageous therapeutic approach. Here, we investigated the effects of broadly inhibiting Gq activation in vitro and ex vivo using receptor-dependent and receptor-independent strategies. P4pal-10 is a protease activated receptor 4-derived pepducin that exhibits efficacy toward multiple Gq-coupled receptors. Mechanistic studies demonstrated that P4pal-10 selectively inhibits all G protein coupling to several Gq-coupled receptors, including protease activated receptor 1, muscarinic acetylcholine M3, and histamine H1 receptors, while demonstrating no direct effect on Gq. We also evaluated the ability of FR900359, also known as UBO-QIC, to directly inhibit Gq activation. FR900359 inhibited spontaneous Gαq nucleotide exchange, while having little effect on Gαsßγ, Gαißγ, or Gα12/13ßγ heterotrimer activity. Both P4pal-10 and FR900359 inhibited Gq-mediated intracellular signaling and primary human airway smooth muscle growth, whereas only FR900359 effectively interdicted agonist-promoted airway contraction in human precision cut lung slices. These studies serve as a proof of concept that the broad-based inhibition of Gq activation may be a useful therapeutic approach to treat multiple common pathologies of airway disease.


Assuntos
Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/antagonistas & inibidores , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Pulmão/metabolismo , Músculo Liso/metabolismo , Células Cultivadas , Células HEK293 , Células HeLa , Humanos , Pulmão/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Oligopeptídeos/farmacologia , Oligopeptídeos/uso terapêutico , Técnicas de Cultura de Órgãos , Transtornos Respiratórios/tratamento farmacológico , Transtornos Respiratórios/metabolismo
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