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1.
Proc Natl Acad Sci U S A ; 119(10): e2112397119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35239443

RESUMO

SignificanceThe modulation of growth hormone secretagogue receptor-1a (GHSR1a) signaling is a promising strategy for treating brain conditions of metabolism, aging, and addiction. GHSR1a activation results in pleiotropic physiological outcomes through distinct and pharmacologically separable G protein- and ß-arrestin (ßarr)-dependent signaling pathways. Thus, pathway-selective modulation can enable improved pharmacotherapeutics that can promote therapeutic efficacy while mitigating side effects. Here, we describe the discovery of a brain-penetrant small molecule, N8279 (NCATS-SM8864), that biases GHSR1a conformations toward Gαq activation and reduces aberrant dopaminergic behavior in mice. N8279 represents a promising chemical scaffold to advance the development of better treatments for GHSR1a-related brain disorders involving the pathological dysregulation of dopamine.


Assuntos
Encéfalo/metabolismo , Dopamina/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Receptores de Grelina/metabolismo , Animais , Dopamina/genética , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/genética , Masculino , Camundongos , Camundongos Knockout , Receptores de Grelina/genética
2.
Life Sci ; 268: 118936, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33421523

RESUMO

AIMS: During oxidative stress mitochondria become the main source of endogenous reactive oxygen species (ROS) production. In the present study, we aimed to clarify the effects of pharmacological PARP-1 inhibition on mitochondrial function and quality control processes. MAIN METHODS: L-2286, a quinazoline-derivative PARP inhibitor, protects against cardiovascular remodeling and heart failure by favorable modulation of signaling routes. We examined the effects of PARP-1 inhibition on mitochondrial quality control processes and function in vivo and in vitro. Spontaneously hypertensive rats (SHRs) were treated with L-2286 or placebo. In the in vitro model, 150 µM H2O2 stress was applied on neonatal rat cardiomyocytes (NRCM). KEY FINDINGS: PARP-inhibition prevented the development of left ventricular hypertrophy in SHRs. The interfibrillar mitochondrial network were less fragmented, the average mitochondrial size was bigger and showed higher cristae density compared to untreated SHRs. Dynamin related protein 1 (Drp1) translocation and therefore the fission of mitochondria was inhibited by L-2286 treatment. Moreover, L-2286 treatment increased the amount of fusion proteins (Opa1, Mfn2), thus preserving structural stability. PARP-inhibition also preserved the mitochondrial genome integrity. In addition, the mitochondrial biogenesis was also enhanced due to L-2286 treatment, leading to an overall increase in the ATP production and improvement in survival of stressed cells. SIGNIFICANCE: Our results suggest that the modulation of mitochondrial dynamics and biogenesis can be a promising therapeutical target in hypertension-induced myocardial remodeling and heart failure.


Assuntos
Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Mitocôndrias Cardíacas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Animais , Células Cultivadas , Citrato (si)-Sintase/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Eletrocardiografia , Glutationa/metabolismo , Hipertrofia Ventricular Esquerda/etiologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Mitocôndrias Cardíacas/ultraestrutura , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/patologia , Peptídeo Natriurético Encefálico/sangue , Piperidinas/farmacologia , Quinazolinas/farmacologia , Ratos Endogâmicos SHR , Ratos Wistar
3.
Biol Futur ; 71(4): 427-434, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34554464

RESUMO

4-aminopyridine (4-AP) is a widely used drug that induces seizure activity in rodents, especially in rats, although there is no consensus in the literature on the dose to be used in mice. The aim of the present study was to investigate the effect of the intraperitoneal administration of 4-AP in two doses (4 and 10 mg/kg) in vivo. EEG, movement, and video recordings were made simultaneously in male B6 mice to specify the details of the seizures and to determine whether there is a suitable non-lethal dose for seizure induction and for further molecular studies. Seizure behavior in mice differs from that seen in rats, with no characteristic stages of epileptic seizures, but with spiking and seizure activity. Seizure activity, although produced at both doses without being lethal, induced different changes of the EEG pattern. Smaller dose induced a lower amplitude seizure activity, decreased spiking activity and later onset of seizures, while higher dose induced a much more intense brain seizure activity and severe trembling. It is concluded that the intraperitoneal administration of 4-AP at a dose of 10 mg/kg induces explicit seizure activity in mice which is repeatable and can be suitable for further molecular research.


Assuntos
4-Aminopiridina/efeitos adversos , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Epilepsia/etiologia , Animais , Modelos Animais de Doenças , Camundongos , Bloqueadores dos Canais de Potássio/efeitos adversos
4.
Transplant Proc ; 51(4): 1263-1267, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31101211

RESUMO

Thoracic organ transplantation made a fresh start in Hungary with the first double lung transplant in December 2015. This major leap in Hungarian transplantation was preceded by almost 10 years of preparation, new infrastructure development, and structural changes not only at the organizational level but in human resources as well. In the following years, until recently, altogether 47 lung transplants were performed on 24 men and 23 women. The underlying pathologies were as follows: chronic obstructive pulmonary disease, 25; cystic fibrosis, 11; idiopathic pulmonary fibrosis, 7; as well as other diseases, including bronchiectasis, eosinophilic granuloma, lymphangioleiomyomatosis, and primary pulmonary hypertension in 4 cases. The youngest recipient was 13 and the oldest was 65 years old. Overall survival rates at 30 days and at 1 year were 96% and 82%, respectively. No patients were lost in the cystic fibrosis and other diseases group, whereas the 1-year survival rates of the chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis groups were 73% and 71%, respectively. The results show the robustness and viability of the program, although there is still opportunity for further improvement. In this short paper, we summarize the fields of possible further cooperation of thoracic and cardiac teams as well as future challenges facing the new Hungarian lung transplant program.


Assuntos
Cardiologia , Pneumopatias/cirurgia , Transplante de Pulmão/métodos , Transplante de Pulmão/estatística & dados numéricos , Adolescente , Adulto , Idoso , Feminino , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Cirurgiões , Taxa de Sobrevida , Adulto Jovem
5.
Transplant Proc ; 51(4): 1296-1298, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31101218

RESUMO

Lung transplant is an effective way to treat many end-stage lung diseases. However, one of the main barriers of allograft organ transplant is still the immunologic rejection of transplanted tissue, which is a response of the HLA molecules. Rejection is a complex process involving both T-cell-mediated delayed-type hypersensitivity reactions and antibody-mediated hypersensitivity reactions to histocompatibility molecules on foreign grafts. We report the case of a 25-year-old female patient with cystic fibrosis who underwent 2 lung transplants because of her initial diagnosis and appearance of bronchiolitis obliterans syndrome after the first transplant. Only 13 months after the second transplant, despite the therapies applied, a new rejection occurred associated with high mean fluorescent intensity donor-specific antibody levels, which resulted later in the death of the patient. The present case draws attention to the importance of matching HLA molecules between donor and recipient in addition to immunosuppressive therapy.


Assuntos
Fibrose Cística/cirurgia , Rejeição de Enxerto/imunologia , Transplante de Pulmão/efeitos adversos , Reoperação/efeitos adversos , Adulto , Bronquiolite Obliterante/etiologia , Bronquiolite Obliterante/cirurgia , Feminino , Antígenos HLA/imunologia , Humanos , Transplante Homólogo/efeitos adversos
6.
Transplant Proc ; 49(7): 1538-1543, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28838436

RESUMO

Until December 2015, Hungarian patients' lung transplantations (LTXs) were done at the Medical University of Vienna. After several years of preparation, the National Hungarian Lung Transplantation Program was launched and the first milestone LTX was performed in Budapest on December 12, 2015. During the first 12 months, 18 lung transplantations took place in Hungary, including the first one. Data were retrospectively collected to analyze the early postoperative problems of the first 18 LTX patients of the newly launched Hungarian National Lung Transplantation Program. No patients with primary pulmonary hypertension and no children were transplanted during this period. We found that the postoperative problems of LTX differ from those of other huge thoracic surgeries both in a quantitative and a qualitative manner. We also reveal problems that are not present with other thoracic surgeries. The wide variety of problems during the early postoperative period after LTX can be managed by a highly organized and coordinated interdisciplinary teamwork.


Assuntos
Transplante de Pulmão/efeitos adversos , Complicações Pós-Operatórias/etiologia , Feminino , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos
7.
Transplant Proc ; 49(7): 1544-1548, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28838437

RESUMO

Lung transplantation (LUTX) became a worldwide accepted standard therapy for certain well-defined chronic end-stage lung diseases. Until recently, patients on mechanical ventilation or extracorporeal life support techniques were hardly eligible for LUTX because of the inferior short-term results. However, a paradigm shift has occurred, and now these techniques represent bridging options to LUTX for listed patients. In the current practice, transplantation from the intensive care unit (ICU) is not extraordinary in patients on the waiting list. On the other hand, transplantation of an ICU patient who has previously been healthy without any chronic lung disease is still exceptional. Here we report a unique case of a 37-year-old woman without any relevant medical history who developed acute lung failure based on a cryptogenic organizing pneumonia. Her condition rapidly deteriorated and she required mechanical support, then she was bridged to transplantation on venovenous extracorporeal membrane oxygenation. She was listed for LUTX, and despite elevated panel-reactive antibody values, positive crossmatch LUTX was performed. Induction therapy, alemtuzumab, plasmapheresis, and intravenous immunoglobulin were administered. Her recovery was slow but finally she could be discharged from hospital in stable condition. After 2 months at home, she was readmitted to the hospital with respiratory failure from combined antibody-mediated rejection and infection. Before December 2015, the launch of Hungarian National Lung Transplantation Program, Hungarian patients were transplanted in Vienna. This case presents an exceptional example of national and international teamwork that aimed to save a young woman's life.


Assuntos
Pneumonia em Organização Criptogênica/complicações , Transplante de Pulmão/métodos , Insuficiência Respiratória/cirurgia , Doença Aguda , Adulto , Pneumonia em Organização Criptogênica/patologia , Progressão da Doença , Oxigenação por Membrana Extracorpórea , Feminino , Humanos , Terapia de Imunossupressão , Respiração Artificial , Insuficiência Respiratória/etiologia
8.
Trauma Case Rep ; 9: 34-37, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29644322

RESUMO

Periprosthetic femoral fractures are rare but significant events following total hip replacement. Metaphyseal short stems have recently been popularized as a bone preserving alternative to conventional uncemented total hip replacement. We present two periprosthetic femur fractures which occurred around two different metaphyseal uncemented stem designs. Successful conservative treatment was possible in both cases achieving bony union and excellent clinical results.

9.
Transplant Proc ; 48(7): 2555-2557, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27742347

RESUMO

BACKGROUND: The most common conditions leading to death after simultaneous pancreas-kidney transplantations (SPKs) are cardiovascular diseases. The aim of this study was to test the platelet aggregation inhibitor acetylsalicylic acid (ASA) resistance in patients after SPKs, including investigations into the triggering factors. METHODS: Thirty-two patients (22 men, 10 women; overall age, 47.4 ± 8.6 years) were involved in our study and took 100 mg ASA per day. We used optical platelet aggregometry to detect resistance. RESULTS: Resistance occurred in 40.6% of the study group. However, with the use of logistic regression analysis, the examined 24 factors did not show any significant correspondence with resistance. CONCLUSIONS: The incidence of ASA resistance seems to be higher compared with other groups, but the triggering effect is still unproved. Clarifying this question should be important regarding the mortality- and morbidity-reducing capacity of antiplatelet drugs in the management of cardiovascular conditions.


Assuntos
Aspirina/uso terapêutico , Resistência a Medicamentos , Transplante de Rim/efeitos adversos , Transplante de Pâncreas/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Adulto , Idoso , Doenças Cardiovasculares/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos
10.
Clin Hemorheol Microcirc ; 63(3): 235-43, 2016 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-27258195

RESUMO

INTRODUCTION: Restoration of blood flow after prolonged acute ischemia causes further injury to tissues. The role of increased oxidative stress is emphasized in the pathogenesis, and impairment of hemorheological factors may also hinder proper microcirculation. Controlled reperfusion at lowered pressure with diluted blood may help to decrease reperfusion injury. METHODS: Four-hour infrarenal aortic clamping was performed in 16 Yorkshire pigs. In 8 animals blood flow was restored subsequently (full reperfusion, FR), in the other 8 animals clamping was followed by an initial 30 minutes of controlled reperfusion (CR) at 60 mmHg pressure with a 1 : 1 ratio mixture of blood and reperfusion solution. Blood samples were taken before the intervention, at the end of ischemia, 15 minutes, 60 minutes, 1 day and 1 week after the start of reperfusion. Hemorheological parameters were measured. RESULTS: Hematocrit, plasma and whole blood viscosity decreased significantly during CR, these attenuated at 1 day. At 1 week whole blood and plasma viscosities were elevated in the FR group. Erythrocyte deformability did not change significantly at any measurements. Erythrocyte aggregation decreased during CR but not in FR, and was found elevated in both groups at 1 week. CONCLUSION: Our results suggest slightly improved hemorheological properties in case of controlled reperfusion compared to full reperfusion, which may help to reduce tissue damage.


Assuntos
Aorta Abdominal/patologia , Hemorreologia , Isquemia/fisiopatologia , Traumatismo por Reperfusão/sangue , Reperfusão/métodos , Animais , Hemodinâmica , Microcirculação , Estresse Oxidativo , Traumatismo por Reperfusão/patologia , Suínos
11.
Catheter Cardiovasc Interv ; 88(6): 923-931, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27258764

RESUMO

PURPOSE: Our aim was to evaluate the acute success and complication rates of the transradial and transulnar access for iliac artery stenting using sheathless guiding systems. METHODS: Clinical and angiographic data from 156 consecutive patients with symptomatic iliac artery stenosis who were treated with transradial or transulnar access were evaluated. All patients underwent Duplex ultrasound before and after the intervention. The primary endpoints were the procedural success rate, major adverse events, and access site complication rates. The secondary endpoints were the angiographic result of the iliac artery intervention, fluoroscopy time, X-ray dose, procedure length, crossover rate to another puncture site and hospitalization duration. The impact of the learning curve was also investigated, along with right or left radial access. RESULTS: The indication for the intervention was intermittent claudication in 109 patients (69.9%), critical limb ischemia in 44 (28.2%) subjects and acute limb ischemia in three individuals (1.9%). Technical success was achieved in 155 patients (99.4%), with a crossover rate of 3.8%. Radial and ulnar artery access was used in 151 (96.8%) and 7 (4.5%) patients, respectively. The Ankle-brachial index increased from 0.69 [0.65-0.72] to 0.91 [0.88-0.95] as a result of the procedures (P < 0.001). The cumulative incidence of major adverse events was 3.8% at the 2-month follow-up (0% in patients with intermittent claudication and 13.8% in patients with critical limb ischemia). Radial artery access site complications were encountered in eight patients (5.1%). We documented decreased X-ray doses (1742.0 [783.9-2701] vs. 1435 [991.1-1879] vs. 692.8 [275.3-1110] Gy cm-2 P < 0.05) over time; however, the fluoroscopy time, procedure time, and contrast consumption were not significantly different. Left hand access was not associated with significantly better results than right radial artery access. CONCLUSIONS: Iliac artery stenting can be safely and effectively performed using radial or ulnar artery access and sheathless guiding catheters, with acceptable complication rates and high levels of technical success. The physician learning curve plays an important role in decreasing the X-ray dose. © 2016 The Authors. Catheterization and Cardiovascular Interventions Published by Wiley Periodicals, Inc.


Assuntos
Angiografia/instrumentação , Angioplastia com Balão/instrumentação , Cateterismo Periférico/instrumentação , Artéria Ilíaca , Claudicação Intermitente/terapia , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Claudicação Intermitente/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Artéria Radial , Estudos Retrospectivos , Artéria Ulnar , Ultrassonografia Doppler Dupla
12.
Acta Physiol Hung ; 101(4): 429-37, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25532954

RESUMO

Capsaicin is a well-known component of red pepper. Recent studies have shown that capsaicin could prevent gastric ulcer provoked by various NSAID-s like acetylsalicylic acid (ASA). Primary objective of this human clinical phase I trial was to investigate whether two different doses of capsaicin co-administered with ASA could alter the inhibitory effect of ASA on platelet aggregation. 15 healthy male subjects were involved in the study and treated orally with 400 µg capsaicin, 800 µg capsaicin, 500 mg ASA, 400 µg capsaicin+500 mg ASA and 800 µg capsaicin+500 mg ASA. Blood was drawn before and 1, 2, 6 and 24 hours after the drug administration. After that epinephrine induced platelet aggregation was measured by optical aggregometry. Between treatments, volunteers had a 6-day wash-out period. Our results showed that capsaicin had no effect on platelet aggregation, while as expected, ASA monotherapy resulted in a significant and clinically effective platelet aggregation inhibition (p ≤ 0.001). The combined ASA-capsaicin therapies reached equivalent effectiveness in platelet aggregation inhibition as ASA monotherapy. Our investigation proved that capsaicin did not influence the inhibitory effect of ASA on platelet aggregation, thus the capsaicin-ASA treatment would combine the antiplatelet effect of ASA with the possible gastroprotection of capsaicin.


Assuntos
Antiulcerosos/administração & dosagem , Aspirina/administração & dosagem , Capsaicina/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Antiulcerosos/sangue , Antiulcerosos/farmacocinética , Aspirina/sangue , Aspirina/farmacocinética , Capsaicina/sangue , Capsaicina/farmacocinética , Interações Medicamentosas , Voluntários Saudáveis , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/sangue , Inibidores da Agregação Plaquetária/farmacocinética , Testes de Função Plaquetária , Método Simples-Cego , Adulto Jovem
13.
Encephale ; 40 Suppl 2: S91-S102, 2014 Jun.
Artigo em Francês | MEDLINE | ID: mdl-24948480

RESUMO

Job tenure for people with severe mental disorders (e.g., schizophrenia) remains a stumbling-block to their work integration. However, the length of job tenure can vary according to the workplace (e.g., provided resources) and the work context (e.g., regular market, social firms). This gap can be explained in part by diverse organisational components, particularly the implementation of work accommodations, which is related to the disclosure of the mental disorder in the workplace. Indeed, in the scientific literature, the principal reason associated with disclosure is in regards to requesting work accommodations. The main objective of this paper is to increase our understanding of the relationships between these three concepts - disclosure of a mental disorder, work accommodations and natural supports, and job tenure - by reviewing the specialized literature and presenting the work of the authors of this paper. To do so, the authors will address the following questions: How do we define 'disclosure' of a mental disorder in the workplace and what are the strategies to consider before disclosing? What is the decision-making process related to disclosure in the workplace? How are the three concepts - disclosure of the mental disorder in the workplace, work accommodations and job tenure - intertwined? Finally, how can employment specialists facilitate the work integration of people with severe mental disorders by considering the three concepts mentioned above? Results from a review of the literature show that disclosure of a mental disorder is a dialectical process that goes beyond the question: to tell or not to tell? In fact, it is not a single binary decision. Several components are associated with the disclosure concept, and can be summarized by the questions: What, how, when and to whom to disclose his/her mental condition? Reasons for disclosing his/her mental disorder in the workplace are numerous, characterized by personal, interpersonal and work environmental factors, on one hand. On the other hand, disclosure has potential consequences, both positive (e.g., to obtain work accommodations) and negative (e.g., stigma). A decision-making process takes place when people with a severe mental disorder think about the possibility of disclosing their mental condition in the workplace - a complex decisional process involving the need to evaluate different aspects (i.e. individual, interpersonal and work environmental factors). Also, the literature supports the fact that requiring work accommodations is often related to the disclosure of the mental disorder, when natural supports in the workplace are not available. The literature is scarce regarding the correlations between the concepts of disclosure, implementation of work accommodations and job tenure; however, a more recent study demonstrated this significant relationship, in which the supervisor and co-worker supports are crucial. Employment specialists or counselors recognise the importance of planned disclosure as a means to obtain access to work adjustments in the workplace and to prevent stigma. The employment specialist working in supported employment programs for instance, could adopt with his/her clients a plan for managing the pros and cons of disclosure of the mental disorder in the workplace; this plan is entitled: Managing personal information. It consists of several steps - for example, to collect details of any sensitive information such as diagnosis, to identify work restrictions with the client, to have a common agreement (employment specialists and clients together) on terms to describe work restrictions - to help clients feel empowered and more confident as productive and valued workers. This plan allows employment specialists to work through the disclosure concept, often negatively connoted, and to adopt a more normalising strategy. Furthermore, additional tools for supporting the management of personal information plan could be used such as the Decision-Making About Disclosure Scale, the Barriers to Employment and Coping Efficacy Scale, and the Work Accommodation and Natural Support Scale, to name a few. To conclude, job tenure for people with severe mental disorders is not a pious vow, several pragmatic ingredients for intervening on this issue are now available.


Assuntos
Readaptação ao Emprego/psicologia , Transtornos Mentais/psicologia , Transtornos Mentais/reabilitação , Reabilitação Vocacional/psicologia , Autorrevelação , Adulto , Confidencialidade , Humanos , Transtornos Mentais/diagnóstico , Seleção de Pessoal , Reorganização de Recursos Humanos , Quebeque , Esquizofrenia/diagnóstico , Esquizofrenia/reabilitação , Psicologia do Esquizofrênico
14.
Cancer Gene Ther ; 21(4): 171-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24722357

RESUMO

Immune responses against oncolytic adenovirus (Ad) vectors are thought to limit vector anti-tumor efficacy. With Syrian hamsters, which are immunocompetent and whose tumors and normal tissues are permissive for replication of Ad5-based oncolytic Ad vectors, treating with high-dose cyclophosphamide (CP) to suppress the immune system and exert chemotherapeutic effects enhances Ad vector anti-tumor efficacy. However, long-term CP treatment and immunosuppression can lead to anemia and vector spread to normal tissues. Here, we employed three cycles of transient high-dose CP administration plus intratumoral injection of the oncolytic Ad vector VRX-007 followed by withdrawal of CP. Each cycle lasted 4-6 weeks. This protocol allowed the hamsters to remain healthy so the study could be continued for ~100 days. The tumors were very well suppressed throughout the study. With immunocompetent hamsters, the vector retarded tumor growth initially, but after 3-4 weeks the tumors resumed rapid growth and further injections of vector were ineffective. Preimmunization of the hamsters with Ad5 prevented vector spillover from the tumor to the liver yet still allowed for effective long-term anti-tumor efficacy. Our results suggest that a clinical protocol might be developed with cycles of transient chemotherapy plus intratumoral vector injection to achieve significant anti-tumor efficacy while minimizing the side effects of cytostatic treatment.


Assuntos
Adenoviridae/fisiologia , Ciclofosfamida/administração & dosagem , Vetores Genéticos/efeitos dos fármacos , Neoplasias Experimentais/prevenção & controle , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/fisiologia , Adenoviridae/genética , Adenoviridae/imunologia , Animais , Antineoplásicos Alquilantes/administração & dosagem , Linhagem Celular Tumoral , Cricetinae , Imunossupressores/administração & dosagem , Mesocricetus , Neoplasias Experimentais/genética , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/virologia , Vírus Oncolíticos/genética , Vírus Oncolíticos/imunologia
15.
Br J Cancer ; 110(7): 1733-43, 2014 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-24619073

RESUMO

BACKGROUND: Identification and development of drugs that can effectively modulate the therapeutic efficacy and toxicity of chemotherapy remain an unmet challenge. We evaluated the effects of Se-methylselenocysteine (MSC) on the toxicity and antitumour activity of cyclophosphamide, cisplatin, oxaliplatin, and irinotecan in animal models. METHODS: Cyclophosphamide, cisplatin, and oxaliplatin were administered by a single i.v. injection and irinotecan by i.v. weekly × 4 schedules. For the combination, MSC was administered daily via the oral route for 7 days in mice and daily for 14 days in rats before and concurrent with drug administration. RESULTS: Se-methylselenocysteine significantly protected against organ-specific toxicity induced by lethal doses of cyclophosphamide, cisplatin, oxaliplatin, and irinotecan. These include diarrhoea, stomatitis, alopecia, bladder, kidney, and bone marrow toxicities. Protection from lethal toxicity by MSC was associated with enhanced antitumour activity in rats bearing advanced Ward colorectal carcinoma and in nude mice bearing human squamous cell carcinoma of the head and neck, FaDu, and A253 xenografts. CONCLUSIONS: Se-methylselenocysteine offers selective protection against organ-specific toxicity induced by clinically active agents and enhances further antitumour activity, resulting in improved therapeutic index. These data provided the rationale for the need to clinically evaluate MSC as selective modulator of the antitumour activity and selectivity of anticancer drugs.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citoproteção , Neoplasias/tratamento farmacológico , Selenocisteína/análogos & derivados , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Feminino , Humanos , Irinotecano , Camundongos , Camundongos Nus , Neoplasias/patologia , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Ratos , Ratos Endogâmicos F344 , Selenocisteína/administração & dosagem , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Biochim Biophys Acta ; 1844(8): 1415-26, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24440405

RESUMO

Glioblastoma, an aggressive brain tumor, has a poor prognosis and a high risk of recurrence. An improved chemotherapeutic approach is required to complement radiation therapy. Gold(I) complexes bearing phosphole ligands are promising agents in the treatment of cancer and disturb the redox balance and proliferation of cancer cells by inhibiting disulfide reductases. Here, we report on the antitumor properties of the gold(I) complex 1-phenyl-bis(2-pyridyl)phosphole gold chloride thio-ß-d-glucose tetraacetate (GoPI-sugar), which exhibits antiproliferative effects on human (NCH82, NCH89) and rat (C6) glioma cell lines. Compared to carmustine (BCNU), an established nitrosourea compound for the treatment of glioblastomas that inhibits the proliferation of these glioma cell lines with an IC50 of 430µM, GoPI-sugar is more effective by two orders of magnitude. Moreover, GoPI-sugar inhibits malignant glioma growth in vivo in a C6 glioma rat model and significantly reduces tumor volume while being well tolerated. Both the gold(I) chloro- and thiosugar-substituted phospholes interact with DNA albeit more weakly for the latter. Furthermore, GoPI-sugar irreversibly and potently inhibits thioredoxin reductase (IC50 4.3nM) and human glutathione reductase (IC50 88.5nM). However, treatment with GoPI-sugar did not significantly alter redox parameters in the brain tissue of treated animals. This might be due to compensatory upregulation of redox-related enzymes but might also indicate that the antiproliferative effects of GoPI-sugar in vivo are rather based on DNA interaction and inhibition of topoisomerase I than on the disturbance of redox equilibrium. Since GoPI-sugar is highly effective against glioblastomas and well tolerated, it represents a most promising lead for drug development. This article is part of a Special Issue entitled: Thiol-Based Redox Processes.


Assuntos
Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Glioma/tratamento farmacológico , Ouro/química , Compostos Organofosforados/síntese química , Compostos Organofosforados/farmacologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Movimento Celular/efeitos dos fármacos , Glioma/metabolismo , Glioma/patologia , Glutationa/metabolismo , Glutationa Redutase/antagonistas & inibidores , Glutationa Redutase/metabolismo , Humanos , Masculino , Ratos , Ratos Wistar , Tiorredoxina Dissulfeto Redutase/antagonistas & inibidores , Tiorredoxina Dissulfeto Redutase/metabolismo , Células Tumorais Cultivadas
17.
Clin Hemorheol Microcirc ; 56(1): 1-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23076007

RESUMO

BACKGROUND: Acetylsalicylic acid (ASA) plays an important role in the treatment and prevention of cardiovascular diseases. Metamizole (MET) is an analgesic and antipyretic medicine, it is not used as an antiplatelet drug. OBJECTIVES: We aimed to examine the antiplatelet effect of MET and the possible interactions between the drugs. METHODS: In our in vitro investigations different concentrations of ASA and MET solutions were added to blood. To examine the interactions MET and ASA were added together. In our in vivo crossover study intravenous MET, oral ASA or both drugs together were administered. Epinephrine and adenosine-diphosphate induced platelet aggregation was determined by optical aggregometry. RESULTS: Epinephrine-induced aggregation was completely inhibited in all ASA and MET concentrations in vitro. Lower, ineffective concentration of MET prevented the antiplatelet effect of ASA. The inhibition was completely restored when higher concentration of ASA was used or when ASA was added first. Our in vivo study showed that in the MET group rapid onset of inhibition was developed and there was no inhibition after one day. In the ASA group platelet aggregation decreased slowly but still had significant inhibitory effect after 72 hours. Combined therapy showed similar changes to the MET group. CONCLUSION: Antiplatelet effect of MET and ASA did not differ significantly in vitro. The observations may indicate a competitive interaction between the two drugs. The in vivo experiments showed that intravenously administered MET is an effective antiplatelet drug and can be considered as a therapeutic alternative, when ASA cannot be used in oral form.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Dipirona/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Estudos Cross-Over , Interações Medicamentosas , Quimioterapia Combinada , Epinefrina/farmacologia , Feminino , Humanos , Masculino , Agregação Plaquetária/efeitos dos fármacos , Resultado do Tratamento , Adulto Jovem
18.
Clin Hemorheol Microcirc ; 56(2): 87-99, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23089886

RESUMO

Consumption of red wine is associated with a decreased risk of several cardiovascular diseases (e.g., coronary artery disease, stroke), but unfortunately literature reports regarding ethanol's effects on hemorheological parameters are not concordant. In the present study, red blood cell (RBC) deformability was tested via laser ektacytometry (LORCA, 0.3-30 Pa) using two approaches: 1) addition of ethanol to whole blood at 0.25%-2% followed by incubation and testing in ethanol-free LORCA medium; 2) addition of ethanol to the LORCA medium at 0.25%-6% then testing untreated native RBC in these media. The effects of ethanol on deformability for oxidatively stressed RBC were investigated as were changes of RBC aggregation (Myrenne Aggregometer) for cells in autologous plasma or 3% 70 kDa dextran. Significant dose-related increases of RBC deformability were observed at 0.25% (p < 0.05) and higher concentrations only if ethanol was in the LORCA medium; no changes occurred for cells previously incubated with ethanol then tested in ethanol-free medium. The impaired deformability of cells pre-exposed to oxidative stress was improved only if ethanol was in the LORCA medium. RBC aggregation decreased with concentration at 0.25% and higher for cells in both autologous plasma and dextran 70. Our results indicate that ethanol reversibly improves erythrocyte deformability and irreversibly decreases erythrocyte aggregation; the relevance of these results to the health benefits of moderate wine consumption require further investigation.


Assuntos
Agregação Eritrocítica/efeitos dos fármacos , Deformação Eritrocítica/efeitos dos fármacos , Eritrócitos/citologia , Etanol/metabolismo , Vinho , Adulto , Doenças Cardiovasculares/prevenção & controle , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Humanos , Estresse Oxidativo/efeitos dos fármacos , Vinho/análise
19.
Clin Hemorheol Microcirc ; 56(1): 13-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23089888

RESUMO

Pieces of epidemiological evidence have supported that moderate red wine consumption reduces the risk of cardiovascular diseases (French-paradox). Our previous in vitro experiment has demonstrated favourable hemorheological effects of red wine, alcohol-free red wine extract and ethanol. Thirty-nine healthy, non-smoking male volunteers between 18-40 years were assigned into two groups: control group had drunk water, while red wine group had consumed 2 dl of red wine each day at dinner for 3 weeks. No alcohol had been drunk for one week prior to the study. Blood was obtained in the morning of the first and last day. Hematocrit (Hct), plasma (PV) and whole blood viscosity (WBV) (Hevimet 40 capillary viscometer), red blood cell (RBC) aggregation (Myrenne and LORCA aggregometer) and deformability (LORCA ektacytometer) were measured and Hct/WBV ratio was calculated to determine oxygen carrying capacity. Hct was adjusted to 40%. Hct and PV were not affected. WBV remained unchanged in controls, but it considerably decreased in the red wine group compared to the 3-week control group, while Hct/WBV ratio became significantly higher in the red wine group compared to the control (p < 0.05). RBC aggregation significantly decreased in the red wine group and became significantly lower compared to the 3-week controls (p < 0.05). Red wine significantly increased RBC deformability (p < 0.05) at high shear stress. Our results show that moderate red wine consumption has beneficial effects on hemorheological parameters which may contribute to the French-paradox.


Assuntos
Consumo de Bebidas Alcoólicas/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/prevenção & controle , Vinho , Adolescente , Adulto , Viscosidade Sanguínea , Agregação Eritrocítica , Deformação Eritrocítica , Hematócrito , Hemorreologia , Humanos , Masculino , Adulto Jovem
20.
Clin Hemorheol Microcirc ; 56(3): 197-204, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23445629

RESUMO

Cardiovascular diseases (CVD) are the most frequent cause of death throughout the world. The coronary vessel system is a special part of the circulation since there is a continuous change in blood flow, perfusion pressure and shear rate during each cardiac cycle. It is also the place of the narrowest capillaries in the human body, therefore the role of rheological alterations may be of greater importance than in the other parts of the circulatory system. During the past decades, our group has investigated hemorheological parameters (HP) in over 1,000 patients diagnosed with various forms of ischemic heart disease (IHD). In one prospective study, we measured the HP of patients with acute coronary syndrome (ACS). On admission, all examined variables were significantly worse than those of control subjects. During the hospital phase, some of the HP showed further deterioration, and HP remained in the pathologic range during the follow-up period. In another study, we showed that HP are in close correlation with the severity of coronary artery disease. In patients treated with percutaneous coronary intervention, changes in HP were very similar to those observed in subjects with ACS. In a recent study, we analyzed HP in patients undergoing CABG surgery. Our data suggest a hemorheological advantage of off-pump surgery. In another study low Hct/WBV ratio can be regarded as a risk factor of cardiac death in IHD. Our data indicate that rheological parameters are significantly altered in patients with IHD: the extent of the alterations is in excellent correlation with the clinical severity of the disease. Our findings prove that HP play a critical role in the pathogenesis of myocardial ischemia. In recent in vitro and in vivo studies we have investigated the effects of red wine on hemorheological parameters. Our results show that moderate red wine consumption has beneficial effects on hemorheological parameters which may contribute to the French paradox.


Assuntos
Viscosidade Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/sangue , Hemorreologia/efeitos dos fármacos , Isquemia Miocárdica/sangue , Doenças Cardiovasculares/fisiopatologia , Feminino , Humanos , Masculino , Isquemia Miocárdica/fisiopatologia , Fatores de Risco
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