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1.
Cell ; 187(10): 2536-2556.e30, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38653237

RESUMO

Cysteine-focused chemical proteomic platforms have accelerated the clinical development of covalent inhibitors for a wide range of targets in cancer. However, how different oncogenic contexts influence cysteine targeting remains unknown. To address this question, we have developed "DrugMap," an atlas of cysteine ligandability compiled across 416 cancer cell lines. We unexpectedly find that cysteine ligandability varies across cancer cell lines, and we attribute this to differences in cellular redox states, protein conformational changes, and genetic mutations. Leveraging these findings, we identify actionable cysteines in NF-κB1 and SOX10 and develop corresponding covalent ligands that block the activity of these transcription factors. We demonstrate that the NF-κB1 probe blocks DNA binding, whereas the SOX10 ligand increases SOX10-SOX10 interactions and disrupts melanoma transcriptional signaling. Our findings reveal heterogeneity in cysteine ligandability across cancers, pinpoint cell-intrinsic features driving cysteine targeting, and illustrate the use of covalent probes to disrupt oncogenic transcription-factor activity.


Assuntos
Cisteína , Neoplasias , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Cisteína/metabolismo , Cisteína/química , Ligantes , Melanoma/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , NF-kappa B/química , NF-kappa B/metabolismo , Oxirredução , Transdução de Sinais , Fatores de Transcrição SOXE/química , Fatores de Transcrição SOXE/metabolismo
2.
bioRxiv ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37961514

RESUMO

Cysteine-focused chemical proteomic platforms have accelerated the clinical development of covalent inhibitors of a wide-range of targets in cancer. However, how different oncogenic contexts influence cysteine targeting remains unknown. To address this question, we have developed DrugMap , an atlas of cysteine ligandability compiled across 416 cancer cell lines. We unexpectedly find that cysteine ligandability varies across cancer cell lines, and we attribute this to differences in cellular redox states, protein conformational changes, and genetic mutations. Leveraging these findings, we identify actionable cysteines in NFκB1 and SOX10 and develop corresponding covalent ligands that block the activity of these transcription factors. We demonstrate that the NFκB1 probe blocks DNA binding, whereas the SOX10 ligand increases SOX10-SOX10 interactions and disrupts melanoma transcriptional signaling. Our findings reveal heterogeneity in cysteine ligandability across cancers, pinpoint cell-intrinsic features driving cysteine targeting, and illustrate the use of covalent probes to disrupt oncogenic transcription factor activity.

3.
Int J STD AIDS ; 33(8): 740-750, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35701863

RESUMO

The main objective of this guideline is to assist practitioners in managing individuals diagnosed with Trichomonas vaginalis (TV). It offers recommendations on the diagnostic tests, treatment regimens and health promotion principles needed for the effective management of TV. It covers the management of the initial presentation, as well as how to prevent transmission and future re-infection. It is aimed primarily at people aged 16 years or older presenting to health care professionals, working in departments offering specialist care in sexually transmitted infection (STI) management within the United Kingdom. However, the principles of the recommendations are applicable across all levels of STI care providers (N.B. non-specialist services may need to develop, where appropriate, local care pathways).


Assuntos
Infecções por HIV , Saúde Sexual , Infecções Sexualmente Transmissíveis , Tricomoníase , Vaginite por Trichomonas , Trichomonas vaginalis , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Promoção da Saúde , Humanos , Prevalência , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/tratamento farmacológico , Infecções Sexualmente Transmissíveis/prevenção & controle , Tricomoníase/diagnóstico , Tricomoníase/tratamento farmacológico , Tricomoníase/epidemiologia , Vaginite por Trichomonas/diagnóstico , Vaginite por Trichomonas/tratamento farmacológico , Vaginite por Trichomonas/epidemiologia
4.
Mult Scler Relat Disord ; 63: 103832, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35512502

RESUMO

BACKGROUND: Some pathways involved in the pathogenesis of psoriasis share similarities with processes involved in multiple sclerosis (MS) pathogenesis. However, the association between MS and psoriasis is poorly understood. Since disease-modifying therapies for MS have various targets, it may be possible that the occurrence of psoriasis varies by drug. OBJECTIVE: To analyze the frequency of psoriasis reports in patients treated with various disease-modifying therapies for MS. METHODS: Data was collected using the FDA Adverse Event Reporting System (FAERS) and OpenFDA database between January 2009 and June 2020. The study analyzed total reports of psoriasis out of total reports in the "Skin and Subcutaneous Tissue Disorders" category for each drug and explored age, sex distribution, and report source. OpenFDA data was used to perform statistical analyses including reporting odds ratios (ROR) and information components. RESULTS: The study identified 517 psoriasis reports of 45,547 total skin and subcutaneous tissue disorders (1.13%) in FAERS. The highest proportions of reports in this study were associated with rituximab, ocrelizumab, and interferon beta 1a. The lowest proportion of reports were associated with glatiramer acetate, alemtuzumab, dimethyl fumarate and teriflunomide. Reports of other autoimmune skin disorders were minimal (29 vitiligo, 33 pemphigoid, and 7 pemphigus). Patients primarily drove reports for most DMTs versus healthcare providers. The proportion of reports from female patients were the highest for each DMT except alemtuzumab. OpenFDA query retrieved 302 total reports of psoriasis. Significantly increased reporting odds ratios (RORs, 95% confidence interval) of psoriasis were noted for rituximab (7.14, 3.92-13.00), ocrelizumab (3.79, 2.74-5.23), and fingolimod (1.33, 1.01-1.76). Significantly decreased RORs were noted for natalizumab (0.53, 0.36-0.80), glatiramer acetate (0.58, 0.35-0.96), and dimethyl fumarate (0.71, 0.53-0.94). CONCLUSION: There are frequent reports of psoriasis in MS patients treated with various DMTs. However, reports and RORs were disproportionally high in association with B cell depleting therapies. Further research is required to determine if certain DMTs may serve as better options for individuals affected by, or at high-risk for developing psoriasis.


Assuntos
Imunossupressores , Esclerose Múltipla , Psoríase , Alemtuzumab/efeitos adversos , Alemtuzumab/uso terapêutico , Fumarato de Dimetilo/efeitos adversos , Fumarato de Dimetilo/uso terapêutico , Feminino , Acetato de Glatiramer/efeitos adversos , Acetato de Glatiramer/uso terapêutico , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/epidemiologia , Psoríase/induzido quimicamente , Psoríase/epidemiologia , Rituximab/efeitos adversos , Rituximab/uso terapêutico
5.
Biomed Opt Express ; 9(7): 3178-3192, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29984092

RESUMO

We present the retinal plenoptoscope, a novel light field retinal imaging device designed to overcome many of the problems that limit the use of portable non-mydriatic fundus cameras, including image quality and lack of stereopsis. The design and prototype construction of this device is detailed and the ideal relationship between the eye pupil, system aperture stop and micro-image separation is investigated. A comparison of the theoretical entrance pupil size, multi-view baseline and depth resolution indicates that a higher degree of stereopsis is possible than with stereo fundus cameras. We also show that the effects of corneal backscatter on image quality can be removed through a novel method of glare identification and selective image rendering. This method is then extended to produce glare-free depth maps from densely estimated depth fields, creating representations of retinal topography from a single exposure. These methods are demonstrated on physical models and live human eyes using a prototype device based on a Lytro Illum consumer light field camera. The Retinal Plenoptoscope offers a viable, robust modality for non-mydriatic color and 3-D retinal imaging.

6.
Cancer Discov ; 8(7): 836-849, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29657135

RESUMO

The receptor tyrosine kinase rearranged during transfection (RET) is an oncogenic driver activated in multiple cancers, including non-small cell lung cancer (NSCLC), medullary thyroid cancer (MTC), and papillary thyroid cancer. No approved therapies have been designed to target RET; treatment has been limited to multikinase inhibitors (MKI), which can have significant off-target toxicities and limited efficacy. BLU-667 is a highly potent and selective RET inhibitor designed to overcome these limitations. In vitro, BLU-667 demonstrated ≥10-fold increased potency over approved MKIs against oncogenic RET variants and resistance mutants. In vivo, BLU-667 potently inhibited growth of NSCLC and thyroid cancer xenografts driven by various RET mutations and fusions without inhibiting VEGFR2. In first-in-human testing, BLU-667 significantly inhibited RET signaling and induced durable clinical responses in patients with RET-altered NSCLC and MTC without notable off-target toxicity, providing clinical validation for selective RET targeting.Significance: Patients with RET-driven cancers derive limited benefit from available MKIs. BLU-667 is a potent and selective RET inhibitor that induces tumor regression in cancer models with RET mutations and fusions. BLU-667 attenuated RET signaling and produced durable clinical responses in patients with RET-altered tumors, clinically validating selective RET targeting. Cancer Discov; 8(7); 836-49. ©2018 AACR.See related commentary by Iams and Lovly, p. 797This article is highlighted in the In This Issue feature, p. 781.


Assuntos
Antineoplásicos/uso terapêutico , Mutação , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas c-ret/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-ret/genética , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Pirimidinas/uso terapêutico , Animais , Antineoplásicos/farmacologia , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/genética , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-ret/metabolismo , Pirazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Sci Rep ; 8(1): 3842, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29497109

RESUMO

The visual consequences of melanopsin photoreception in humans are not well understood. Here we studied melanopsin photoreception using a technique of photoreceptor silent substitution with five calibrated spectral lights after minimising the effects of individual differences in optical pre-receptoral filtering and desensitising penumbral cones in the shadow of retinal blood vessels. We demonstrate that putative melanopsin-mediated image-forming vision corresponds to an opponent S-OFF L + M-ON response property, with an average temporal resolution up to approximately 5 Hz, and >10x higher thresholds than red-green colour vision. With a capacity for signalling colour and integrating slowly changing lights, melanopsin-expressing intrinsically photosensitive retinal ganglion cells maybe the fifth photoreceptor type for peripheral vision.


Assuntos
Visão de Cores/fisiologia , Opsinas de Bastonetes/fisiologia , Visão Ocular/fisiologia , Adulto , Cor , Feminino , Humanos , Luz , Masculino , Estimulação Luminosa/métodos , Células Fotorreceptoras/fisiologia , Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Ganglionares da Retina/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Opsinas de Bastonetes/metabolismo
8.
Invest Ophthalmol Vis Sci ; 58(2): 990-996, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28535270

RESUMO

Purpose: Melanopsin expressing intrinsically photosensitive retinal ganglion cells (ipRGC) input to multiple brain regions including those for pupil control, circadian rhythms, sleep and mood regulation. Here we measured ipRGC function and its relationship to sleep quality and depression in patients with advanced AMD. Methods: The melanopsin-mediated post-illumination pupil response (PIPR) was measured in 53 patients with advanced AMD (age 78.8 ± 8.8 years) and in 20 healthy controls (age 72.5 ± 3.3 years). Sleep quality and efficiency was assessed using the Pittsburgh Sleep Quality Index (PSQI). Risk of depression was determined using the Center for Epidemiologic Studies Depression questionnaire. Results: The group with AMD showed significantly reduced pupil constrictions (P = 0.039); PIPR amplitudes (P = 0.003); global sleep scores (P = 0.01); and higher levels of depression (P < 0.001) than the control group. There was a significant correlation between the PIPR amplitude and global sleep score in the AMD group (P = 0.01). The amplitude of PIPR significantly correlated with sleep efficiency (P = 0.008; regression, P = 0.01, R2 = 0.13), but not sleep quality (P = 0.23) in the AMD group. There was no correlation between PIPR and depression scores. Conclusions: Intrinsically photosensitive RGC dysfunction in advanced AMD contributes to the observed reduction in sleep efficiency. The correlation between the melanopsin-mediated PIPR and sleep may indicate reduced photic input to the suprachiasmatic nucleus and ventrolateral preoptic area due to ipRGC dysfunction in AMD.


Assuntos
Ritmo Circadiano , Depressão/etiologia , Degeneração Macular/fisiopatologia , Reflexo Pupilar/fisiologia , Células Ganglionares da Retina/fisiologia , Sono/fisiologia , Idoso , Idoso de 80 Anos ou mais , Depressão/epidemiologia , Depressão/fisiopatologia , Feminino , Humanos , Incidência , Degeneração Macular/complicações , Degeneração Macular/metabolismo , Masculino , Estimulação Luminosa , Queensland/epidemiologia , Opsinas de Bastonetes/metabolismo , Tomografia de Coerência Óptica
9.
Thyroid ; 27(5): 732-737, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28314380

RESUMO

BACKGROUND: The thyroid hormone-inactivating enzyme type 3 deiodinase (D3) is induced during hypertrophic and ischemic cardiomyopathy, leading to a state of local cardiac hypothyroidism. Whether D3 induction occurs in dilated cardiomyopathy is unknown. METHODS: This study characterized changes in cardiac D3 and thyroid hormone signaling in a transgenic model of progressive dilated cardiomyopathy (TG9 mice). RESULTS: Cardiac D3 was dramatically induced 15-fold during the progression of dilated cardiomyopathy in TG9 mice. This D3 induction localized to cardiomyocytes and was associated with a decrease in myocardial thyroid hormone signaling. CONCLUSIONS: Cardiac D3 is induced in a mouse model of dilated cardiomyopathy, indicating that D3 induction may be a general response to diverse forms of cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada/metabolismo , Iodeto Peroxidase/metabolismo , Miocárdio/metabolismo , Tiroxina/sangue , Tri-Iodotironina/sangue , Animais , Cardiomiopatia Dilatada/patologia , Modelos Animais de Doenças , Progressão da Doença , Camundongos , Camundongos Transgênicos , Miocárdio/patologia
10.
Acta Ophthalmol ; 94(8): e772-e778, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27225020

RESUMO

PURPOSE: To determine whether decreasing illumination of the Pelli-Robson contrast sensitivity (CS) chart and MP-1 microperimeter to low mesopic conditions is more sensitive to vision changes occurring with healthy ageing and in early and intermediate age-related macular degeneration (AMD) and whether these mesopic tests can differentiate visual function between healthy older participants with and without AMD risk genotypes. METHODS: Retinal sensitivity was measured in 98 healthy participants (19-85 years) and 21 AMD (AREDS Grade 2/3) patients (73.9 ± 6.5 years) using the Pelli-Robson CS chart and MP-1 microperimeter under low mesopic and standard illumination. The effect of ageing and AMD on retinal sensitivity was estimated using regression analysis. Healthy older participants (>50 years; n = 24) were genotyped for AMD risk genes CFH and/or ARMS2 and retinal sensitivity was compared between genotypes. RESULTS: With healthy ageing, photopic and mesopic Pelli-Robson CS showed a similar decline (-0.004 log CS/year). In AMD, photopic CS showed a similar decline to healthy ageing (-0.004 log CS/year) while mesopic CS was significantly reduced (-0.007 log CS/year). Both standard and low mesopic microperimetry showed a significant decline (-0.51 and -0.73% contrast/year) with healthy ageing and greater decline (-0.73 and -0.99% contrast/year) with AMD onset. Pelli-Robson CS and microperimetry sensitivity did not differ between AMD risk genotypes in healthy participants. CONCLUSIONS: Mesopic Pelli-Robson CS detects functional deficits before photopic CS in early and intermediate AMD that can be differentiated from ageing. This test can be easily administered in clinical practice and may provide a means for early detection of retinal dysfunction.


Assuntos
Envelhecimento/fisiologia , Sensibilidades de Contraste/fisiologia , Degeneração Macular/fisiopatologia , Visão Mesópica/fisiologia , Retina/fisiopatologia , Campos Visuais/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fator H do Complemento/genética , Feminino , Genótipo , Voluntários Saudáveis , Humanos , Degeneração Macular/genética , Masculino , Pessoa de Meia-Idade , Proteínas/genética , Testes Visuais , Testes de Campo Visual , Adulto Jovem
11.
Invest Ophthalmol Vis Sci ; 56(11): 6906-13, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26505464

RESUMO

PURPOSE: To determine whether melanopsin-expressing intrinsically photosensitive retinal ganglion cell (ipRGC) inputs to the pupil light reflex (PLR) are affected in early age-related macular degeneration (AMD). METHODS: The PLR was measured in 40 participants (20 early AMD and 20 age-matched controls) using a custom-built Maxwellian view pupillometer. Sinusoidal stimuli (0.5 Hz, 11.9 seconds duration, 35.6° diameter) were presented to the study eye and the consensual pupil response was measured to lights with high melanopsin excitation (464 nm [blue]) and with low melanopsin excitation (638 nm [red]) that biased activation to the outer retina. Two melanopsin PLR metrics were quantified: the phase amplitude percentage (PAP) during the sinusoidal stimulus presentation and the post-illumination pupil response (PIPR). The PLR during stimulus presentation was analyzed using latency to constriction, the transient pupil response and maximum pupil constriction metrics. Diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curves. RESULTS: The blue PIPR was significantly less sustained in the early AMD group (P < 0.001). The red PIPR was not significantly different between groups (P > 0.05). The PAP and blue stimulus constriction amplitude were significantly lower in the early AMD group (P < 0.05). There was no significant difference between groups in the latency or transient amplitude for both stimuli (P > 0.05). ROC analysis showed excellent diagnostic accuracy for the blue PIPR metrics (area under the curve > 0.9). CONCLUSIONS: This is the initial report that the melanopsin-controlled PIPR is dysfunctional in early AMD. The noninvasive, objective measurement of the ipRGC controlled PIPR has excellent diagnostic accuracy for early AMD.


Assuntos
Degeneração Macular/fisiopatologia , Reflexo Pupilar/fisiologia , Opsinas de Bastonetes/fisiologia , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Estimulação Luminosa , Reflexo Pupilar/efeitos da radiação , Retina/fisiopatologia
12.
Endocrinology ; 155(10): 4061-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25004090

RESUMO

Type 3 deiodinase (D3), the physiologic inactivator of thyroid hormones, is induced during tissue injury and regeneration. This has led to the hypotheses that D3 impacts injury tolerance by reducing local T3 signaling and contributes to the fall in serum triiodothyronine (T3) observed in up to 75% of sick patients (termed the low T3 syndrome). Here we show that a novel mutant mouse with hepatocyte-specific D3 deficiency has normal local responses to toxin-induced hepatonecrosis, including normal degrees of tissue necrosis and intact regeneration, but accelerated systemic recovery from illness-induced hypothyroxinemia and hypotriiodothyroninemia, demonstrating that peripheral D3 expression is a key modulator of the low T3 syndrome.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/reabilitação , Hepatócitos/metabolismo , Iodeto Peroxidase/genética , Regeneração Hepática/genética , Fígado/patologia , Animais , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Feminino , Iodeto Peroxidase/deficiência , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Necrose/induzido quimicamente , Necrose/genética , Especificidade de Órgãos/genética , Recuperação de Função Fisiológica/genética , Toxinas Biológicas
13.
Endocrinology ; 155(10): 4069-80, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25004091

RESUMO

Thyroid hormone is a master regulator of differentiation and growth, and its action is terminated by the enzymatic removal of an inner-ring iodine catalyzed by the selenoenzyme type 3 deiodinase (dio3). Our studies of the zebrafish reveal that the dio3 gene is duplicated in this species and that embryonic deiodination is an important determinant of embryo size. Although both dio3 paralogs encode enzymatically active proteins with high affinity for thyroid hormones, their anatomic patterns of expression are markedly divergent and only embryos with knockdown of dio3b, a biallelically expressed selenoenzyme expressed in the developing central nervous system, manifest severe thyroid hormone-dependent growth restriction at 72 hours post fertilization. This indicates that the embryonic deficiency of dio3, once considered only a placental enzyme, causes microsomia independently of placental physiology and raises the intriguing possibility that fetal abnormalities in human deiodination may present as intrauterine growth retardation. By mapping the gene structures and enzymatic properties of all four zebrafish deiodinases, we also identify dio3b as the first multiexon dio3 gene, containing a large intron separating its open reading frame from its selenocysteine insertion sequence (SECIS) element.


Assuntos
Tamanho Corporal/genética , Iodeto Peroxidase/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Embrião não Mamífero , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Células HEK293 , Humanos , Isoenzimas/genética
15.
J Opt Soc Am A Opt Image Sci Vis ; 31(4): A7-A14, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24695205

RESUMO

We studied the effect of rod-cone interactions on mesopic visual reaction time (RT). Rod and cone photoreceptor excitations were independently controlled using a four-primary photostimulator. It was observed that (1) lateral rod-cone interactions increase the cone-mediated RTs; (2) the rod-cone interactions are strongest when rod sensitivity is maximal in a dark surround, but weaker with increased rod activity in a light surround; and (3) the presence of a dark surround nonselectively increased the mean and variability of chromatic (+L-M, S-cone) and luminance (L+M+S) RTs independent of the level of rod activity. The results demonstrate that lateral rod-cone interactions must be considered when deriving mesopic luminous efficiency using RT.


Assuntos
Percepção de Cores/fisiologia , Interação Cone-Bastonete/fisiologia , Humanos , Psicofísica , Tempo de Reação , Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Bastonetes/citologia
16.
N Engl J Med ; 370(14): 1327-34, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24693892

RESUMO

Gastrointestinal stromal tumors (GISTs) are resistant to traditional chemotherapy but are responsive to the tyrosine kinase inhibitors imatinib and sunitinib. The use of these agents has improved the outcome for patients but is associated with adverse effects, including hypothyroidism. Multiple mechanisms of this effect have been proposed, including decreased iodine organification and glandular capillary regression. Here we report the finding of consumptive hypothyroidism caused by marked overexpression of the thyroid hormone-inactivating enzyme type 3 iodothyronine deiodinase (D3) within the tumor. Affected patients warrant increased monitoring and may require supernormal thyroid hormone supplementation.


Assuntos
Neoplasias Gastrointestinais/enzimologia , Tumores do Estroma Gastrointestinal/enzimologia , Hipotireoidismo/enzimologia , Hipotireoidismo/etiologia , Iodeto Peroxidase/metabolismo , Hormônios Tireóideos/deficiência , Neoplasias Gastrointestinais/complicações , Neoplasias Gastrointestinais/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/complicações , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Humanos , Iodeto Peroxidase/genética , Masculino , Pessoa de Meia-Idade , Radiografia Abdominal
17.
J Vis ; 13(1)2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23325348

RESUMO

This study investigates the time-course and post-receptoral pathway signaling of photoreceptor interactions when the rod (R) and three cone (L, M, S) photoreceptor classes contribute to mesopic vision. A four-primary photostimulator independently controls photoreceptor activity in human observers. The first experiment defines the temporal adaptation response of receptoral (L-, S-cone, rod) and post-receptoral (LMS, LMSR, +L-M) signaling and interactions. Here we show that nonopponent cone-cone interactions (L-cone, LMS, LMSR) have monophasic temporal response patterns whereas opponent signals (+L-M, S-cone) show biphasic response patterns with slower recovery. By comparison, rod-cone interactions with nonopponent signals have faster adaptation responses and reduced sensitivity loss whereas opponent rod-cone interactions are small or absent. Additionally, the rod-rod interaction differs from these interaction types and acts to increase rod sensitivity due to temporal summation but with a slower time course. The second experiment shows that the temporal profile of the rod signal alters the relative rod contributions to the three primary post-receptoral pathways. We demonstrate that rod signals generate luminance (+L+M) signals mediated via the MC pathway with all rod temporal profiles and chromatic signals (L/L+M, S/L+M) in both the PC and KC pathways with durations >75 ms. Thus, we propose that the change in relative weighting of rod signals within the post-receptoral pathways contributes to the sensitivity and temporal response of rod and cone pathway signaling and interactions.


Assuntos
Sensibilidades de Contraste/fisiologia , Visão Mesópica/fisiologia , Estimulação Luminosa/métodos , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Interação Cone-Bastonete/fisiologia , Adulto , Comunicação Celular , Percepção de Cores/fisiologia , Feminino , Humanos , Luz , Transdução de Sinais
18.
Antioxid Redox Signal ; 14(5): 781-90, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20578962

RESUMO

Postconditioning (PostC), or relief of myocardial ischemia in a stuttered manner, has been shown to reduce infarct size, due in part to upregulation of survival kinase signaling. Virtually all of these data have, however, been obtained in healthy adult cohorts; the question of whether PostC-induced cardioprotection is maintained in the setting of clinically relevant comorbidities has remained largely unexplored. Accordingly, our aim was to assess the consequences of a major risk factor-diabetes-on the infarct-sparing effect of stuttered reflow. Isolated buffer-perfused hearts were obtained from normoglycemic C57BL/6J mice, BKS.Cg-m+/+Lepr(db)/J (db/db) mice (model of type-2 diabetes), C57BL/6J mice injected with streptozotocin (model of type-1 diabetes), and streptozotocin-injected mice in which normoglycemia was re-established by islet cell transplantation. All hearts underwent 30 min of ischemia and, within each cohort, hearts received either standard (control) reperfusion or three to six 10-s cycles of stuttered reflow. PostC reduced infarct size via upregulation of extracellular signal-regulated kinase 1/2 in normoglycemic mice. In contrast, diabetic hearts were refractory to PostC-induced cardioprotection-an effect that, in the type-1 model, was reversed by restoration of normoglycemia. We provide novel evidence for a profound-but potentially reversible-diabetes-induced defect in the cardioprotective efficacy of PostC.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Pós-Condicionamento Isquêmico , Infarto do Miocárdio/complicações , Animais , Modelos Animais de Doenças , Coração/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Distribuição Aleatória , Ratos
19.
J Am Coll Cardiol ; 51(14): 1393-8, 2008 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-18387442

RESUMO

OBJECTIVES: Our aim was to establish whether the efficacy of post-conditioning is maintained in aging hearts. BACKGROUND: Post-conditioning, or relief of myocardial ischemia in a stuttered manner, has been shown to reduce infarct size, in part because of up-regulation of survival kinases (extracellular-signal regulated kinase [ERK] 1/2 or PI3-kinase/Akt) during the early min of reperfusion. All of these data have, however, been obtained in adult populations; the question of whether post-conditioning-induced cardioprotection is maintained in aging cohorts is unknown. METHODS: Isolated buffer-perfused hearts were obtained from 3- to 4-month-old (adult) and 20- to 24-month-old C57BL/6J mice and subjected to 30 min of ischemia. For each cohort, hearts were randomized to receive standard, abrupt (control) reperfusion, or were post-conditioned with 3 or 6 10-s cycles of stuttered reflow. Primary end points were infarct size, cardiac expression of phospho-Akt, phospho-mitogen-activated protein kinase kinase 1/2 and phospho-ERK 1/2, and expression of mitogen-activated protein kinase-phosphatase-1 (MKP-1: phosphatase purported to play a primary role in ERK dephosphorylation). RESULTS: In adult mouse hearts, post-conditioning significantly reduced infarct size via up-regulation of ERK (but not Akt) signaling. In contrast, in the 2-year-old cohort, post-conditioning failed to limit necrosis, possibly a consequence of the deficit in ERK phosphorylation and increased MKP-1 expression seen in old hearts. Indeed, infusion of sodium orthovanadate, a nonspecific MKP inhibitor, attenuated MKP-1 expression and restored the post-conditioned phenotype in old hearts. CONCLUSIONS: Old mouse hearts are refractory to infarct size reduction with post-conditioning, possibly because of an age-associated increase in MKP-1 and resultant deficit in ERK phosphorylation.


Assuntos
Envelhecimento , Sistema de Sinalização das MAP Quinases , Infarto do Miocárdio/fisiopatologia , Reperfusão Miocárdica , Miocárdio/patologia , Animais , Ventrículos do Coração/fisiopatologia , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/complicações , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/patologia , Miocárdio/enzimologia , Fenótipo , Distribuição Aleatória , Fatores de Tempo , Regulação para Cima
20.
Am J Physiol Heart Circ Physiol ; 291(4): H2008-12, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16731645

RESUMO

Considerable attention has focused on the role of protein kinase C (PKC) in triggering the profound infarct-sparing effect of ischemic preconditioning (PC). In contrast, the involvement of inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)], the second messenger generated in parallel with the diacylglycerol-PKC pathway, remains poorly understood. We hypothesized that, if Ins(1,4,5)P(3) signaling [i.e., release of Ins(1,4,5)P(3) and subsequent binding to Ins(1,4,5)P(3) receptors] contributes to PC-induced cardioprotection, then the reduction of infarct size achieved with PC would be attenuated in mice that are deficient in Ins(1,4,5)P(3) receptor protein. To test this concept, hearts were harvested from 1) B6C3Fe-a/a-Itpr-1(opt+/-)/J mutants displaying reduced expression of Ins(1,4,5)P(3) receptor-1 protein, 2) Itpr-1(opt+/+) wild types from the colony, and 3) C57BL/6J mice. All hearts were buffer-perfused and randomized to receive two 5-min episodes of PC ischemia, pretreatment with d-myo-Ins(1,4,5)P(3) [sodium salt of native Ins(1,4,5)P(3)], the mitochondrial ATP-sensitive K(+) channel opener diazoxide, or no intervention (controls). After the treatment phase, all hearts underwent 30-min global ischemia followed by 2 h of reperfusion, and infarct size was delineated by tetrazolium staining. In both wild-type and C57BL/6J cohorts, area of necrosis in hearts that received PC, d-myo-Ins(1,4,5)P(3), and diazoxide averaged 28-35% of the total left ventricle (LV), significantly smaller than the values of 52-53% seen in controls (P < 0.05). In contrast, in Itpr-1(opt+/-) mutants, protection was only seen with diazoxide: neither PC nor d-myo-Ins(1,4,5)P(3) limited infarct size (52-58% vs. 56% of the LV in mutant controls). These data provide novel evidence that Ins(1,4,5)P(3) signaling contributes to infarct size reduction with PC.


Assuntos
Canais de Cálcio/metabolismo , Inositol 1,4,5-Trifosfato/fisiologia , Precondicionamento Isquêmico Miocárdico , Glicoproteínas de Membrana/metabolismo , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Canais de Cálcio/genética , Diazóxido/farmacologia , Regulação da Expressão Gênica , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Inositol 1,4,5-Trifosfato/farmacologia , Receptores de Inositol 1,4,5-Trifosfato , Precondicionamento Isquêmico Miocárdico/métodos , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Infarto do Miocárdio/prevenção & controle , Miocárdio/metabolismo , Proteína Quinase C/fisiologia , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais/fisiologia , Vasodilatadores/farmacologia
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