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1.
Skin Health Dis ; 2(1): e78, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35665216

RESUMO

Background: The activation of melanocortin 1 receptor (MC1R) on melanocytes stimulates the production of eumelanin. A tridecapeptide α melanocyte-stimulating hormone (αMSH) is known to induce skin pigmentation. Objectives: We characterised the properties of a novel oral MC1R agonist dersimelagon (MT-7117) with respect to its specific binding to MC1R, downstream signalling and eumelanin production in experimental models. Methods: The competitive binding and production of intracellular cyclic adenosine 3', 5'-monophosphate in cells expressing recombinant melanocortin receptors were examined. A mouse melanoma cell line B16F1 was used for the evaluation of in vitro melanin production. The in vitro activity of MT-7117 was determined with αMSH and [Nle4, D-Phe7]-αMSH (NDP-αMSH) as reference comparators. The change of coat colour and skin pigmentation were evaluated after repeat administration of MT-7117 by oral gavage to C57BL/6J-Ay/+ mice and cynomolgus monkeys, respectively. Results: MT-7117 showed the highest affinity for human MC1R compared to the other melanocortin receptors evaluated and agonistic activity for human, cynomolgus monkey and mouse MC1R, with EC50 values in the nanomolar range. In B16F1 cells, MT-7117 increased melanin production in a concentration-dependent manner. In vivo, MT-7117 (≥0.3 mg/kg/day p.o.) significantly induced coat colour darkening in mice. MT-7117 (≥1 mg/kg/day p.o.) induced significant skin pigmentation in monkeys and complete reversibility was observed after cessation of its administration. Conclusions: MT-7117 is a novel oral MC1R agonist that induces melanogenesis in vitro and in vivo, suggesting its potential application for the prevention of phototoxic reactions in patients with photodermatoses, such as erythropoietic protoporphyria and X-linked protoporphyria.

2.
BJS Open ; 5(5)2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34518870

RESUMO

BACKGROUND: Studies evaluating the outcomes after laparoscopic resections of transverse colon cancers are scant. This manuscript aimed to compare surgical and oncological outcomes after laparoscopic (Lap) and open procedures for transverse colon carcinomas. METHODS: All consecutive patients who underwent resection for a cancer located in the transverse colon between 2003 and 2019 were reviewed. Patients were categorized according to the surgical approach (Lap versus open) and groups were compared. Outcome measures were the short-term results, complications and functional recovery; moreover, recurrence-free survival (RFS) and overall survival (OS) rates were compared overall and after propensity score matching (PSM) based on age, sex, ASA classification, BMI, carcinoembryonic antigen (CEA) level, use of postoperative chemotherapy, location of tumour, stage and grading, operation time, blood loss and complications. RESULTS: Of 248 transverse resections reviewed, 146 (81 Lap and 65 open) were selected for data analysis. Blood loss, fluid intake and the incidence of wound infection were significantly lower and the hospital stay was significantly shorter in the Lap group (P < 0.001). The operation time and incidence of complications (Clavien-Dindo classification grade 3 or above) did not differ significantly between the two groups. Mean follow-up was of 75.4 months in the Lap group and 78.6 months in the open group. Regression analyses showed that OS was associated with the postoperative carcinoembryonic antigen (CEA) level (hazard ratio 1.18 (95 per cent c.i. 1.10 to 1.27); P < 0.001), BMI (hazard ratio 0.81 (95 per cent c.i. 0.68 to 0.96); P = 0.017), operation time (hazard ratio 0.99 (95 per cent c.i. 0.97 to 1.00; P = 0.010), and postoperative chemotherapy (hazard ratio 0.27 (95 per cent c.i. 0.08 to 0.96); P = 0.042), while RFS was associated with the postoperative CEA level (hazard ratio 1.13 (95 per cent c.i. 1.07 to 1.20); P < 0.001). PSM selected 42 patients for data comparison of long-term results, and showed no significant differences between groups (RFS: P = 0.530; OS: P = 0.561). CONCLUSION: Lap and open resections for transverse colon cancer provided similar outcomes in terms of severe post-operative complication and long-term results.


Assuntos
Colo Transverso , Neoplasias do Colo , Laparoscopia , Colo Transverso/cirurgia , Neoplasias do Colo/cirurgia , Humanos , Pontuação de Propensão , Estudos Retrospectivos
3.
Chem Sci ; 8(9): 6165-6170, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28989647

RESUMO

Boronic acids are well known for their ability to reversibly interact with the diol groups found in sugars and glycoproteins. However, they are generally indiscriminate in their binding. Herein we describe the discovery of a group of heterocyclic boronic acids demonstrating unusually high affinity and selectivity for sialic acids (SAs or N-acetylneuraminic acid), which are sugar residues that are intimately linked with tumor growth and cancer progression. Remarkably, these interactions strengthen under the weakly acidic pH conditions associated with a hypoxic tumoral microenvironment. In vitro competitive binding assays uncovered a significantly higher ability of 5-boronopicolinic acid, one of the derivatives identified in this work as a strong SA-binder, to interact with cell surface SA in comparison to a gold-standard structure, 3-propionamidophenylboronic acid, which has proven to be an efficient SA-binder in numerous reports. This structure also proved to be suitable for further chemical conjugation with a well-preserved SA-binding capability. These findings suggest an attractive alternative to other ongoing boronic acid based chemistry techniques aiming to achieve tumor-specific chemotherapies and diagnoses.

4.
J Thromb Haemost ; 15(1): 80-90, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27797446

RESUMO

Essentials Endogenous hormone levels' influence on hemostatic factor levels is not fully characterized. We tested for associations of endogenous hormone with hemostatic factor levels in postmenopause. Estrone levels were inversely associated with the natural anticoagulant, protein S antigen. Dehydroepiandrosterone sulfate levels were inversely associated with thrombin generation. SUMMARY: Background Oral use of exogenous estrogen/progestin alters hemostatic factor levels. The influence of endogenous hormones on these levels is incompletely characterized. Objectives Our study aimed to test whether, among postmenopausal women, high levels of estradiol (E2), estrone (E1), testosterone (T), dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), and androstenedione, and low levels of sex hormone-binding globulin (SHBG), are positively associated with measures of thrombin generation (TG), a normalized activated protein C sensitivity ratio (nAPCsr), and factor VII activity (FVIIc), and negatively associated with antithrombin activity (ATc) and total protein S antigen (PSAg). Methods This Heart and Vascular Health study cross-sectional analysis included 131 postmenopausal women without a prior venous thrombosis who were not currently using hormone therapy. Adjusted mean differences in TG, nAPCsr, FVIIc, ATc and PSAg levels associated with differences in hormone levels were estimated using multiple linear regression. We measured E2, E1, total T, DHEAS, DHEA and androstenedione levels by mass spectrometry, SHBG levels by immunoassay, and calculated the level of free T. Results One picogram per milliliter higher E1 levels were associated with 0.24% lower PSAg levels (95% Confidence Interval [CI]: -0.35, -0.12) and 1 µg mL-1 higher DHEAS levels were associated with 40.8 nm lower TG peak values (95% CI: -59.5, -22.2) and 140.7 nm×min lower TG endogenous thrombin potential (ETP) (95% CI: -212.1, -69.4). After multiple comparisons correction, there was no evidence for other associations. Conclusions As hypothesized, higher E1 levels were associated with lower levels of the natural anticoagulant PSAg. Contrary to hypotheses, higher DHEAS levels were associated with differences in TG peak and ETP that suggest less generation of thrombin.


Assuntos
Hemostasia , Pós-Menopausa/sangue , Globulina de Ligação a Hormônio Sexual/metabolismo , Esteroides/sangue , Trombose/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Androstenodiona/sangue , Antitrombinas/metabolismo , Estudos Transversais , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Estrona/sangue , Fator VII/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Proteína C/metabolismo , Proteína S/metabolismo , Testosterona/sangue , Trombina/metabolismo , Adulto Jovem
5.
Cell Mol Biol (Noisy-le-grand) ; 62(12): 74-78, 2016 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-27894404

RESUMO

Streptozotocin (STZ), a naturally occurring chemical, is toxic to the various kinds of cells such as insulin-producing beta cells. However, the beneficial effect of STZ on neuronal cells such as neurite outgrowth-inducing activity has been unknown. In this study, we examined the effect of STZ on neurite outgrowth in mouse neuronal Neuro2a cells. STZ (0.01 mM~5 mM) exerted remarkable neurite outgrowth-inducing activity in Neuro2a cells in a concentration dependent manner. STZ also had the same neurite outgrowth-inducing activity as that of retinoic acid (RA), which is well known neurite outgrowth inducer. As with the result of RA treatment, STZ administration increased MAP2-positive cells. The MAP2-positive cells reflect neurite outgrowth-induced cells. STZ (0.01 mM~5 mM) did not induce cell death, but significantly decreased cell proliferation. The serine/threonine kinase Akt, a downstream target of phosphatidylinositol-3 kinase (PI3K), was transiently phosphorylated at Ser473 and at Thr303 by STZ (5 mM) administration. Glycogen synthase kinase 3ß (GSK3ß), which has been reported to be inactivated by Akt, was also transiently phosphorylated at Ser9 by STZ (5 mM) administration. In addition, a blocker of PI3K, LY294002 (10 µM), significantly attenuated STZ-induced neurite outgrowth. These results suggest that STZ induces neurite outgrowth via activation of PI3K-Akt signaling pathway and GSK3ß inhibition.


Assuntos
Glicogênio Sintase Quinase 3 beta/metabolismo , Crescimento Neuronal/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estreptozocina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromonas/farmacologia , Immunoblotting , Camundongos , Morfolinas/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação/efeitos dos fármacos
6.
Ann R Coll Surg Engl ; 97(4): 291-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26263938

RESUMO

INTRODCUTION: Although nipple sparing mastectomy (NSM) has attracted increased recognition as an alternative to traditional mastectomy approaches, its oncological safety is unclear. The purpose of this study was to compare the local recurrence rate between NSM and total mastectomy (TM). METHODS: Between 2003 and 2013, 121 and 557 patients with stage 0-III breast cancer underwent NSM and TM respectively. Multivariate Cox regression and propensity score models were used to compare the two groups. RESULTS: There was no significant difference in the five-year local recurrence rate between the NSM and TM groups (7.6% vs 4.9%, p=0.398). In multivariate analysis, NSM was not a risk factor for local recurrence (hazard ratio: 1.653, 95% confidence interval: 0.586-4.663, p=0.343). Propensity score matching found similar five-year local recurrence free survival rates between the two groups (92.3% vs 93.7%, p=0.655). CONCLUSIONS: Our results suggest that NSM may provide oncological safety comparable with mastectomy for carefully selected patients.


Assuntos
Neoplasias da Mama , Mastectomia , Mamilos/cirurgia , Tratamentos com Preservação do Órgão , Adulto , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia/efeitos adversos , Mastectomia/métodos , Mastectomia/mortalidade , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/efeitos adversos , Tratamentos com Preservação do Órgão/métodos , Tratamentos com Preservação do Órgão/mortalidade , Pontuação de Propensão , Estudos Retrospectivos
7.
Andrology ; 3(2): 287-92, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25684636

RESUMO

Low serum testosterone (T) is common and increasingly prevalent with increased age. Recent studies report an 'epidemic' of T prescribing and concern about unnecessary T treatment. We investigated the number of men tested for T, the prevalence of low serum T levels, and initiation of T treatment among those with low T levels in men treated at Veterans Affairs (VA) facilities in the Northwest US (VISN 20). We identified male Veterans aged 40-89 years and examined yearly proportions of men tested for T, found to have low T levels (total T < 280 ng/dL, free T < 34 pg/mL, or bioavailable T < 84 ng/dL), and subsequently treated with T from 2002 to 2011. We excluded men who had T treatment in the year prior and men with diagnoses of prostate or breast cancer. Treatment initiation was defined as the first prescription for T within a year following a low T test. From 2002 to 2011, the yearly population of eligible men in VISN 20 increased from 129 247 to 163 572. The proportion of men who had serum T tests increased from 3.2% in 2002 to 5.8% in 2011. Among the tested men, the percentage of men with low T levels increased from 35.0 to 47.3%. However, the proportion of men with low T levels who were given T treatment within a year decreased from 31.0 to 28.0%. Despite large increases in T testing, and detection of men with low T levels, there was a slight decrease in the proportion of men with low T levels who were treated with T. The decrease in T treatment during this time period contrasts with other studies and may be related to higher comorbidity in Veterans and/or VA formulary restrictions on the use of transdermal T formulations.


Assuntos
Testosterona/administração & dosagem , Veteranos , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia de Reposição Hormonal , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos
8.
Dentomaxillofac Radiol ; 43(2): 20130280, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24247589

RESUMO

Osteosarcoma of the temporomandibular joint (TMJ) is rare. We report a case of osteosarcoma in the TMJ of a 62-year-old female, pre-operatively diagnosed to have a benign tumour, and discuss the usefulness and limits of MRI using a TMJ coil as a diagnosis.


Assuntos
Imageamento por Ressonância Magnética/métodos , Osteossarcoma/diagnóstico , Transtornos da Articulação Temporomandibular/diagnóstico , Terapia por Captura de Nêutron de Boro , Diagnóstico Diferencial , Feminino , Humanos , Côndilo Mandibular/patologia , Neoplasias Mandibulares/diagnóstico , Pessoa de Meia-Idade , Invasividade Neoplásica , Disco da Articulação Temporomandibular/patologia
9.
Int J Oral Maxillofac Surg ; 43(2): 185-93, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23992905

RESUMO

To examine the hypothesis that conservative treatment is applicable to younger patients with bilateral mandibular condylar fractures, we studied the effect of ageing on the healing of bilateral mandibular condylar fractures in a rat model. Male Sprague-Dawley rats aged 3, 6, and 36 weeks (n=25/cohort, total n=75) were divided into a fracture group (n=12) and a sham control group (n=12); one rat from each cohort was used as a normal unoperated control. Cell proliferation was evaluated using the bromodeoxyuridine (BrdU) labelling index (LI). Osteochondrogenesis was assessed by the expression of Indian hedgehog (Ihh), type X collagen, and osteocalcin in the condylar head. Condylar fracture healing was found to be delayed by ageing. BrdU LI values in the fracture groups were higher in younger rats than in older rats at 8 weeks after fracture. The number of Ihh-positive cells in the fracture groups increased significantly up to 2 weeks after fracture, and then gradually decreased until 8 weeks after fracture. The findings of this study support the clinical concept of conservative treatment of bilateral condylar fractures in younger patients, but functional issues regarding ramus height and its consequences on occlusion have not been tested in this study.


Assuntos
Envelhecimento/fisiologia , Fixação Interna de Fraturas/métodos , Consolidação da Fratura/fisiologia , Côndilo Mandibular/lesões , Fraturas Mandibulares/cirurgia , Animais , Bromodesoxiuridina , Proliferação de Células , Modelos Animais de Doenças , Técnicas Imunoenzimáticas , Masculino , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley
10.
J Clin Endocrinol Metab ; 98(3): 1198-206, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23348398

RESUMO

CONTEXT: The concentration of intratesticular testosterone (IT-T) required for human spermatogenesis is unknown because spermatogenesis can persist despite the markedly reduced IT-T concentrations observed with LH suppression. Methods to lower IT-T further are needed to determine the relationship between IT-T and spermatogenesis. OBJECTIVE: The objective of the study was to determine the effect of inhibiting the synthesis and metabolism of testosterone (T) on IT-T in gonadotropin-suppressed human testes. DESIGN/SETTING/PATIENTS: Forty normal men participated in a blinded, placebo-controlled, randomized trial at an academic center. INTERVENTION/OUTCOME MEASURES: All men were first administered the GnRH antagonist acyline to suppress LH. Forty-eight hours after acyline administration, subjects were randomly assigned to placebo, ketoconazole (to inhibit T synthesis) at 400 or 800 mg, dutasteride (to inhibit T metabolism) 2.5 mg, or anastrazole (to inhibit T metabolism) 1 mg, daily for 7 days (n = 8/group). Intratesticular steroid concentrations were measured 48 hours after acyline administration alone and again after 7 days of combination treatment. RESULTS: After 7 days of combination treatment, the median IT-T (25th, 75th percentile) in the placebo group was 14 (8.0, 21.2) ng/mL. IT-T was reduced to 3.7 (2.5, 7.1) ng/mL in the ketoconazole 400 mg group and 1.7 (0.8, 4.0) ng/mL in the ketoconazole 800 mg group (P < .001 vs placebo for both comparisons). IT-T concentrations in the dutasteride and anastrazole groups were similar to placebo. CONCLUSION: Combining inhibition of steroidogenesis with gonadotropin suppression lowers IT-T more than gonadotropin suppression alone. This combination might be useful to determine the minimum IT-T concentration necessary for human spermatogenesis, information essential for developing male hormonal contraceptives.


Assuntos
Androgênios/biossíntese , Anticoncepção/métodos , Cetoconazol/administração & dosagem , Oligopeptídeos/administração & dosagem , Testículo/efeitos dos fármacos , Inibidores de 14-alfa Desmetilase/administração & dosagem , 17-alfa-Hidroxiprogesterona/sangue , Adolescente , Adulto , Androgênios/sangue , Androstenodiona/biossíntese , Androstenodiona/sangue , Desidroepiandrosterona/biossíntese , Desidroepiandrosterona/sangue , Desenho de Fármacos , Sinergismo Farmacológico , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Testículo/metabolismo , Testosterona/biossíntese , Testosterona/sangue , Adulto Jovem
11.
J Bone Joint Surg Br ; 93(12): 1638-45, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22161927

RESUMO

We evaluated the maturation of grafted bone in cases of successful fusion after a one- or two-level posterior lumbar interbody fusion (PLIF) using interbody carbon cages. We carried out a five-year prospective longitudinal radiological evaluation of patients using plain radiographs and CT scans. One year after surgery, 117 patients with an early successful fusion were selected for inclusion in the study. Radiological evaluation of interbody bone fusion was graded on a 4-point scale. The mean grades of all radiological and CT assessments increased in the five years after surgery, and differences compared to the previous time interval were statistically significant for three or four years after surgery. Because the grafted bone continues to mature for three years after surgery, the success of a fusion should not be assessed until at least three years have elapsed. There were no significant differences in the longitudinal patterns of grafted bone maturity between iliac bone and local bone. However, iliac bone grafting may remodel faster than local bone.


Assuntos
Transplante Ósseo/diagnóstico por imagem , Ílio/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Fusão Vertebral/métodos , Adulto , Idoso , Transplante Ósseo/métodos , Carbono/uso terapêutico , Feminino , Humanos , Ílio/cirurgia , Fixadores Internos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doenças da Coluna Vertebral/cirurgia , Fusão Vertebral/instrumentação , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
12.
Eur J Vasc Endovasc Surg ; 39(6): 739-44, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20096610

RESUMO

We report our experience treating four patients with acutely bleeding angiomyolipoma (AML) of sizes between 4 and 12 cm who were managed with endovascular embolisation with a mean follow-up of 10 months. In our case series, we demonstrate that endovascular embolisation in the acute setting for bleeding AMLs is a viable treatment option. AML should be in the differential diagnosis of acutely bleeding renal masses, even when there is no fat assessed by computed tomography (CT) imaging in the renal mass.


Assuntos
Angiomiolipoma/terapia , Cateterismo/métodos , Embolização Terapêutica/métodos , Hemorragia/terapia , Neoplasias Renais/terapia , Doença Aguda , Adulto , Angiografia , Angiomiolipoma/complicações , Angiomiolipoma/diagnóstico , Diagnóstico Diferencial , Feminino , Seguimentos , Hemorragia/diagnóstico , Hemorragia/etiologia , Humanos , Neoplasias Renais/complicações , Neoplasias Renais/diagnóstico , Masculino , Pessoa de Meia-Idade , Nefrectomia , Espaço Retroperitoneal , Tomografia Computadorizada por Raios X
13.
Methods Mol Biol ; 610: 29-39, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20013170

RESUMO

The partial pressure of oxygen (pO(2)) plays a determining role in the energy metabolism of aerobic cells. However, low pO(2) level induces pathophysiological conditions such as tumor hypoxia, ischemia or reperfusion injury, and delayed/altered wound healing. Especially, pO(2) level in the tumor is known to be related to tumor progression and effectiveness of radiotherapy. To monitor the pO(2) levels in vivo, continuous wave (CW) and time-domain (TD) electron paramagnetic resonance (EPR) spectroscopy method was used, in which surface coil resonator and Lithium phthalocyanine (LiPc) as oxygen sensor were crucial. Once LiPc particles are embedded in a desired location of organ/tissue, the pO(2) level can be monitored repeatedly and non-invasively. This method is based on the effect of oxygen concentration on the EPR spectra of LiPc which offers several advantages as follows: (1) high sensitivity, (2) minimum invasiveness, (3) repeated measurements, (4) absence of toxicity (non-toxic), and (5) measurement in a local region of the tissue with embedded LiPc. Therefore, in this chapter, we describe the method using CW and TD EPR spectroscopy with oxygen-sensitive particle, LiPc, for in vivo monitoring of oxygen.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Indóis/química , Compostos Organometálicos/química , Oximetria/métodos , Oxigênio/química , Animais , Dióxido de Carbono/química , Dióxido de Carbono/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica/instrumentação , Feminino , Camundongos , Micro-Ondas , Estrutura Molecular , Neoplasias/química , Neoplasias/metabolismo , Oximetria/instrumentação , Oxigênio/metabolismo , Consumo de Oxigênio , Radiossensibilizantes/química , Radiossensibilizantes/metabolismo , Marcadores de Spin
14.
Cell Mol Biol (Noisy-le-grand) ; 56 Suppl: OL1447-52, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21215240

RESUMO

Preconditioning of sublethal ischemia implies a cytoprotective mechanism against subsequent ischemia­induced cell death; however, the precise mechanism by which preconditioning protects against ischemic injury is not known. In the present study, we clarified whether pretreatment with a sublethal concentration of H2O2 could counter subsequent H2O2-induced cytotoxicity and also investigated the mechanisms of the cytoprotective effect of a sublethal concentration of H2O2. Using the MTT reduction assay and Calcein-AM staining assay, we showed that pretreatment with H2O2 (10 µM, 24 hr) of COS7 cells partially protected cells against subsequent H2O2 (6 mM, 1 hr) - induced cytotoxicity. The phosphorylation of Akt/PKB, a downstream target of phosphatydylinositol-3 kinase (PI3K), at Ser473 was augmented by H2O2 (10 µM) administration. This augmentation peaked at 10 minutes after H2O2 (10 µM) treatment and fell to the basal level at 24 hr. A blocker of PI3K, LY294002, significantly attenuated H2O2 (10 µM, 24 hr) - induced cytoprotection. In addition, pretreatment with LY294002 reduced H2O2 (10 µM, 10 min)-induced phosphorylation of Akt at Ser473. These findings suggest that a sublethal concentration of H2O2 exerts a cytoprotective effect against subsequent H2O2-induced cell death and that this cytoprotective effect of H2O2 is mediated by activation of the PI3K-Akt signaling pathway.


Assuntos
Peróxido de Hidrogênio/toxicidade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Animais , Apoptose , Células COS , Chlorocebus aethiops , Cromonas/química , Cromonas/farmacologia , Citoproteção/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Morfolinas/química , Morfolinas/farmacologia , Fosforilação , Fatores de Tempo
15.
J Androl ; 31(2): 138-45, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19779211

RESUMO

Sex steroids are essential for spermatogenesis; however, normal intratesticular concentrations of these hormones in man have not been extensively studied. To improve our understanding of intratesticular hormone concentrations, we performed bilateral testicular aspirations in a group of normal men, determined sex steroid concentrations within each testis, and compared these levels to serum hormone concentrations. Ten healthy human subjects aged 20-49 underwent bilateral testicular aspirations. Intratesticular hormone concentrations of testosterone, dihydrotestosterone (DHT), and estradiol were measured using liquid chromatography-tandem mass spectrometry. Intratesticular testosterone concentrations ranged from 119 to 1251 ng/mL, with a mean of 635 +/- 368 ng/mL. Intratesticular estradiol ranged from 0.41 to 3.9 ng/mL, with a mean of 2.4 +/- 1.3 ng/mL. Intratesticular DHT ranged from 1.1 to 7.9 ng/mL, with a mean of 3.5 +/- 3.2 ng/mL. Intratesticular testosterone and estradiol concentrations correlated highly with serum luteinizing hormone (LH; r = 0.87 and r = 0.70 respectively, P < .01). Intratesticular testosterone correlated highly with serum testosterone. Moreover, a significant correlation between the right and left testes was observed for testosterone (r = 0.82, P = .003), but not for estradiol or DHT. Intratesticular hormone concentrations can be safely assessed by testicular aspiration. Intratesticular testosterone and estradiol correlate highly with serum LH concentrations, and variation in serum LH accounts for most of the variation in intratesticular testosterone among men. In addition, intratesticular testosterone is highly correlated between testes in a given individual. Direct measurement of intratesticular testosterone will improve our understanding of the relationship between intratesticular sex steroids and spermatogenesis, and may have implications for the development of male hormonal contraception.


Assuntos
Di-Hidrotestosterona/análise , Estradiol/análise , Hormônio Luteinizante/sangue , Testículo/química , Testosterona/análise , Adulto , Cromatografia Líquida , Di-Hidrotestosterona/metabolismo , Estradiol/metabolismo , Hormônios Esteroides Gonadais/análise , Hormônios Esteroides Gonadais/metabolismo , Humanos , Masculino , Espectrometria de Massas , Testículo/metabolismo , Testosterona/metabolismo , Adulto Jovem
16.
Braz. j. med. biol. res ; 42(8): 717-721, Aug. 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-520778

RESUMO

Angiotensin-converting enzyme (ACE) activity and polymorphism contribute significantly to the prognosis of patients with cardiomyopathy. The aim of this study was to determine the activity and type of ACE polymorphism in patients with familial and nonfamilial hypertrophic cardiomyopathy (HCM) and to correlate these with echocardiographic measurements (echo-Doppler). We studied 136 patients (76 males) with HCM (69 familial and 67 nonfamilial cases). Mean age was 41 ¡À 17 years. DNA was extracted from blood samples for the polymerase chain reaction and the determination of plasma ACE levels. Left ventricular mass, interventricular septum, and wall thickness were measured. Mean left ventricular mass index, interventricular septum and wall thickness in familial and nonfamilial forms were 154 ¡À 63 and 174 ¡À 57 g/m2 (P = 0.008), 19 ¡À 5 and 21 ¡À 5 mm (P = 0.02), and 10 ¡À 2 and 12 ¡À 3 mm (P = 0.0001), respectively. ACE genotype frequencies were DD = 35%, ID = 52%, and II = 13%. A positive association was observed between serum ACE activity and left ventricular mass index (P = 0.04). Logistic regression showed that ACE activity was twice as high in patients with familial HCM and left ventricular mass index ¡Ý190 g/m2 compared with the nonfamilial form (P = 0.02). No other correlation was observed between ACE polymorphisms and the degree of myocardial hypertrophy. In conclusion, ACE activity, but not ACE polymorphisms, was associated with the degree of myocardialhypertrophy in the patients with HCM.


Assuntos
Adulto , Feminino , Humanos , Masculino , Cardiomiopatia Hipertrófica/enzimologia , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Polimorfismo Genético/genética , Cardiomiopatia Hipertrófica Familiar/enzimologia , Cardiomiopatia Hipertrófica Familiar/genética , Cardiomiopatia Hipertrófica Familiar , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica , Ecocardiografia Doppler , Genótipo , Hipertrofia Ventricular Esquerda , Fenótipo , Índice de Gravidade de Doença
17.
Proc Biol Sci ; 276(1659): 1037-45, 2009 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-19129104

RESUMO

Using baited camera landers, the first images of living fishes were recorded in the hadal zone (6000-11000 m) in the Pacific Ocean. The widespread abyssal macrourid Coryphaenoides yaquinae was observed at a new depth record of approximately 7000 m in the Japan Trench. Two endemic species of liparid were observed at similar depths: Pseudoliparis amblystomopsis in the Japan Trench and Notoliparis kermadecensis in the Kermadec Trench. From these observations, we have documented swimming and feeding behaviour of these species and derived the first estimates of hadal fish abundance. The liparids intercepted bait within 100-200 min but were observed to preferentially feed on scavenging amphipods. Notoliparis kermadecensis act as top predators in the hadal food web, exhibiting up to nine suction-feeding events per minute. Both species showed distinctive swimming gaits: P. amblystomopsis (mean length 22.5 cm) displayed a mean tail-beat frequency of 0.47 Hz and mean caudal:pectoral frequency ratio of 0.76, whereas N. kermadecensis (mean length 31.5 cm) displayed respective values of 1.04 and 2.08 Hz. Despite living at extreme depths, these endemic liparids exhibit similar activity levels compared with shallow-water liparids.


Assuntos
Ecossistema , Comportamento Alimentar/fisiologia , Peixes/fisiologia , Atividade Motora/fisiologia , Animais , Crustáceos , Oceano Pacífico
18.
Clin Exp Med ; 7(1): 30-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17380303

RESUMO

NKT cells are responsible for hepatitis induced either by concanavalin A (Con-A) or alpha-galactosylceramide (alpha-GalCer), and they are also profoundly involved in the generalised Shwartzman reaction (GSR) induced by consecutive injections of interleukin (IL)-12 and lipopolysaccharide (LPS). In the present study, using NC/Nga (NC) mice and SJL mice lacking the Vbeta(+)8 gene, we examined the role of Vbeta(+)8+NKT cells in hepatitis models and in the GSR. The absence of Vbeta(+)8+NKT cells in the liver mononuclear cells (MNC) was confirmed by the alpha-GalCer/CD1d/Ig dimer. Unexpectedly, other dimer+NKT cells including Vbeta7(+)NKT cells in these mice were found to decrease in comparison to that of C57BL/6 mice. No significant hepatocyte injury was observed after alpha-GalCer or Con-A administration in either mice. The serum interferon (IFN)-gamma, IL-4 and tumour necrosis factor (TNF) levels did not increase in these mice after alpha-GalCer injection, however these cytokines substantially increased after Con-A administration, thus suggesting that the roles of NKT cells differ between the two hepatitis models. However, in GSR, although neither mice showed lower IFN-gamma levels after a priming IL-12 injection, they showed TNF levels comparable to those in normal mice after LPS injection, and thus resulted in a decreased but substantial mortality. Although liver MNC from IL-12-injected SJL mice showed an impaired antitumour cytotoxicity, liver MNC of NC mice exhibited a greater antitumour cytotoxicity than that of C57BL/6 mice because liver NK cells proportionally increased in NC mice. These results confirm the critical role that Vbeta8(+)NKT cells play in both liver and multi-organ injury.


Assuntos
Hepatite Animal/imunologia , Células Matadoras Naturais/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/deficiência , Fenômeno de Shwartzman/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Concanavalina A/imunologia , Concanavalina A/toxicidade , Galactosilceramidas/imunologia , Galactosilceramidas/toxicidade , Interferon gama/sangue , Interleucina-4/sangue , Células Matadoras Naturais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Subpopulações de Linfócitos T/efeitos dos fármacos , Fator de Necrose Tumoral alfa/sangue
19.
Psychoneuroendocrinology ; 32(1): 72-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17145137

RESUMO

BACKGROUND: It has been suggested that cognitive changes in response to T supplementation may occur within an ideal range. The objective of this study was to compare the cognitive responses of older, eugonadal men in whom moderate or large increases in serum testosterone levels was induced by exogenous testosterone supplementation. DESIGN: Randomized, double-blind, placebo-controlled study with subsequent grouping of participants according to average increase in circulating T from baseline. SETTING: Community dwelling participants. PARTICIPANTS: Fifty-seven healthy, eugonadal, community dwelling male volunteers, mean age 67 years (+/-11 years). INTERVENTIONS: Participants were randomized to receive weekly intramuscular (i.m.) injections of either 50, 100 or 300 mg T enanthate or placebo (saline) injection for 6 weeks. Cognitive evaluations using a battery of neuropsychological tests were conducted at baseline, weeks 3 and 6 of treatment and after 6 weeks of wash-out. MAIN OUTCOME MEASURES: Performance on cognitive tests of verbal and spatial memory. RESULTS: Men with moderate increases in serum T and/or its metabolites demonstrated significant improvements in verbal and spatial memory. In contrast, men with large or low increases in circulating T levels, failed to demonstrate significant changes in memory. CONCLUSION: These results suggest that in healthy older men, beneficial changes in cognitive function induced by T supplementation are most evident with moderate changes in cognition from moderate to high T supplementation increases in T levels. Large or no to low increases in T levels do not appear to appreciably effect cognition.


Assuntos
Memória/efeitos dos fármacos , Testosterona/análogos & derivados , Comportamento Verbal/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Cognição/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Estradiol/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Testosterona/sangue , Testosterona/farmacologia
20.
Br J Radiol ; 79(945): 725-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16940373

RESUMO

To identify patients with nasopharyngeal cancer in whom the cervical radiation field can be reduced, we classified the growth patterns of nasopharyngeal cancer based on MRI findings into 4 types and performed an evaluation. Based on MRI findings, we classified the growth patterns of primary cancer in 94 patients with nasopharyngeal cancer into Type 1 (superficial type), Type 2 (lateral invasive type), Type 3 (upward invasive type), and Type 4 (anterior extension type), and further classified Type 2, based upon nasopharyngoscopic findings, into Type 2a (unilateral invasive type) and Type 2b (bilateral invasive type). The cervical lymph node metastasis areas were evaluated according to these types. Type 2 showed a significantly higher incidence of cervical lymph node metastasis only on the ipsilateral side than the other types (p = 0.0024). In particular, all patients with Type 2a had cervical lymph node metastasis only on the ipsilateral side (p = 0.0212). This study suggests that the distribution of metastasised cervical lymph nodes depends on the pattern of tumour extent of the primary site.


Assuntos
Metástase Linfática/patologia , Neoplasias Nasofaríngeas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/radioterapia , Pescoço , Doses de Radiação , Estudos Retrospectivos
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