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1.
Eur Rev Med Pharmacol Sci ; 26(15): 5509-5519, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35993648

RESUMO

OBJECTIVE: The nonavalent HPV vaccine has demonstrated its efficacy in women and men who already suffer from HPV genital lesions, with little chances to clear the infection. The efficacy of new therapeutic or complementary alternatives as Ellagic acid plus Annona Muricata (Ellagic acid complex) has emerged recently. Our retrospective study compares the evolution of persistent cervical HPV infection in two cohorts of immunocompetent women after the administration of nonavalent vaccine or Ellagic acid complex. PATIENTS AND METHODS: At Tor Vergata University Hospital, Rome, forty women in childbearing age, suffering from persistent cervical HPV infection, were enrolled in two study's groups: nonavalent HPV vaccine (20 women) vs. Ellagic acid complex tablets (20 who refused the vaccine). Cytological features, HPV DNA genotypes and mRNA oncogenic genes E6/E7 presence and clearance were analyzed and confronted between the groups. RESULTS: Demographics and clinical features of the cohorts were comparable. Evaluation of Pap smear, HPV DNA test and mRNA genes E6/E7, were performed at baseline (T0) and after 6 months (T1) and 12 months (T2) from the last dose of vaccine/tablet. At T1 and T2, Ellagic acid complex group showed a statistical reduction of abnormalities in Pap smears (p = 0.018 and 0.006, respectively), probably due to its direct anti-inflammatory, antioxidative and antiviral activities. At T1, vaccinated group showed a higher rate of HPV clearance (p = 0.001), instead Ellagic acid complex group didn't report significative differences. At T2, respect to T0, both groups showed an increase in percentage of negative HPV DNA detection, although more marked for vaccinated group respect to Ellagic acid complex group (p = 0.039 and 0.062 respectively). Regarding mRNA E6/E7 clearance, at T1 and T2, the group of vaccinated women showed a higher negativization respect to the other group (p= 0.077 and 0.042, respectively). CONCLUSIONS: Despite the limited sample of women enrolled for the present study, the results confirmed the clinical usefulness of HPV vaccination as adjuvant agent for the immune system of women affected by persistent HPV infection. Moreover, in women who refused to be vaccinated, the administration of a biocompound like Ellagic acid plus Annona Muricata, represented an interesting clinical strategy in terms of increasing chance of HPV viral clearance.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Neoplasias do Colo do Útero , Ácido Elágico/uso terapêutico , Feminino , Humanos , Masculino , Proteínas Oncogênicas Virais/genética , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/tratamento farmacológico , Infecções por Papillomavirus/prevenção & controle , RNA Mensageiro/genética , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia , Vacinas Combinadas
2.
Radiologia (Engl Ed) ; 64 Suppl 1: 4-10, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35428466

RESUMO

OBJECTIVE: To evaluate radiology residents' opinions about breast imaging and the possibility of choosing this subspecialty after completing their residency. MATERIAL AND METHODS: We elaborated a 15-question survey aimed at radiology residents in Spain. The survey was approved by the Spanish Society of Breast Imaging (SEDIM) and the Spanish Society of Medical Radiology (SERAM), and it was disseminated by the SERAM through links to Google Forms via social networks and emails. Responses sent between February 21, 2020 and July 31, 2020 were accepted. RESULTS: A total of 72 residents responded to the survey (7.83% response rate); 69.44% of these were third- or fourth-year residents. Of the respondents, 73.61% knew about the SEDIM, and 18.06% knew about the European Society of Breast Imaging. The duration of training programs was three months for 70.83% of respondents. In 7.84% of the responses, residents stated that their supervision was less than 50%, and 70.59% of the residents stated that the rotation exceeded their expectations. One-third of the respondents would consider a fellowship in breast imaging. In all hospitals, residents did diagnostic mammography and breast ultrasound; not all did interventional procedures. Aspects of breast imaging that were rated negatively included the lack of CT studies and the possible legal repercussions of errors. Aspects that were rated positively were dynamics, interventionism, and the role of the radiologist in the process of care for patients with breast cancer. CONCLUSIONS: Most residents considered that their rotations in breast imaging exceeded their expectations; however, only a small percentage of residents would consider specializing in the field.


Assuntos
Internato e Residência , Radiologia , Bolsas de Estudo , Humanos , Mamografia , Radiologia/educação , Inquéritos e Questionários
3.
Radiologia (Engl Ed) ; 2021 Feb 03.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33549316

RESUMO

OBJECTIVE: To evaluate radiology residents' opinions about breast imaging and the possibility of choosing this subspecialty after completing their residency. MATERIAL AND METHODS: We elaborated a 15-question survey aimed at radiology residents in Spain. The survey was approved by the Spanish Society of Breast Imaging (SEDIM) and the Spanish Society of Medical Radiology (SERAM), and it was disseminated by the SERAM through links to Google Forms via social networks and emails. Responses sent between February 21, 2020 and July 31, 2020 were accepted. RESULTS: A total of 72 residents responded to the survey (7.83% response rate); 69.44% of these were third- or fourth-year residents. Of the respondents, 73.61% knew about the SEDIM, and 18.06% knew about the European Society of Breast Imaging. The duration of training programs was three months for 70.83% of respondents. In 7.84% of the responses, residents stated that their supervision was less than 50%, and 70.59% of the residents stated that the rotation exceeded their expectations. One-third of the respondents would consider a fellowship in breast imaging. In all hospitals, residents did diagnostic mammography and breast ultrasound; not all did interventional procedures. Aspects of breast imaging that were rated negatively included the lack of CT studies and the possible legal repercussions of errors. Aspects that were rated positively were dynamics, interventionism, and the role of the radiologist in the process of care for patients with breast cancer. CONCLUSIONS: Most residents considered that their rotations in breast imaging exceeded their expectations; however, only a small percentage of residents would consider specializing in the field.

4.
Mol Neurobiol ; 57(7): 3183-3194, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32504417

RESUMO

MicroRNAs have emerged as regulators of brain development and function. Reduction of miR-101 expression has been reported in rodent hippocampus during ageing, in the brain of Alzheimer's disease (AD) patients and in AD animal models. In this study, we investigated the behavioral and molecular consequences of inhibition of endogenous miR-101 in 4-5-month-old C57BL/6J mice, infused with lentiviral particles expressing a miR-101 sponge (pLSyn-miR-101 sponge) in the CA1 field of the hippocampus. The sponge-infected mouse model showed cognitive impairment. The pLSyn-miR-101 sponge-infected mice were unable to discriminate either a novel object location or a novel object as assessed by object place recognition (OPR) and novel object recognition (NOR) tasks, respectively. Moreover, the sponge-infected mice evaluated for contextual memory in inhibitory avoidance task showed shorter retention latency compared to control pLSyn mice. These cognitive impairment features were associated with increased hippocampal expression of relevant miR-101 target genes, amyloid precursor protein (APP), RanBP9 and Rab5 and overproduction of amyloid beta (Aß) 42 levels, the more toxic species of Aß peptide. Notably, phosphorylation-dependent AMP-activated protein kinase (AMPK) hyperactivation is associated with AD pathology and age-dependent memory decline, and we found AMPK hyperphosphorylation in the hippocampus of pLSyn-miR-101 sponge mice. This study demonstrates that mimicking age-associated loss of miR-101 in hippocampal neurons induces cognitive decline and modulation of AD-related genes in mice.


Assuntos
Doença de Alzheimer/genética , Disfunção Cognitiva/genética , Hipocampo/metabolismo , MicroRNAs/genética , Neurônios/metabolismo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Aprendizagem da Esquiva/fisiologia , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Memória/fisiologia , Camundongos , MicroRNAs/metabolismo , Fragmentos de Peptídeos/metabolismo
5.
Neuropharmacology ; 117: 134-148, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28163105

RESUMO

Nerve Growth Factor (NGF) is being considered as a therapeutic candidate for Alzheimer's disease. However, the development of an NGF-based therapy is limited by its potent pain activity. We have developed a "painless" derivative form of human NGF (NGF61/100), characterized by identical neurotrophic properties but a reduced nociceptive sensitization activity in vivo. Here we characterized the response of rat dorsal root ganglia neurons (DRG) to the NGF derivative NGF61/100, in comparison to that of control NGF (NGF61), analyzing the expression of noxious pro-nociceptive mediators. NGF61/100 displays a neurotrophic activity on DRG neurons comparable to that of control NGF61, despite a reduced activation of PLCγ, Akt and Erk1/2. NGF61/100 does not differ from NGF61 in its ability to up-regulate Substance P (SP) and Calcitonin Gene Related Peptide (CGRP) expression. However, upon Bradykinin (BK) stimulation, NGF61/100-treated DRG neurons release a much lower amount of SP and CGRP, compared to control NGF61 pre-treated neurons. This effect of painless NGF is explained by the reduced up-regulation of BK receptor 2 (B2R), respect to control NGF61. As a consequence, BK treatment reduced phosphorylation of the transient receptor channel subfamily V member 1 (TRPV1) in NGF61/100-treated cultures and induced a significantly lower intracellular Ca2+ mobilization, responsible for the lower release of noxious mediators. Transcriptomic analysis of DRG neurons treated with NGF61/100 or control NGF allowed identifying a small number of nociceptive-related genes that constitute an "NGF pain fingerprint", whose differential regulation by NGF61/100 provides a strong mechanistic basis for its selective reduced pain sensitizing actions.


Assuntos
Fator de Crescimento Neural/efeitos adversos , Fator de Crescimento Neural/farmacologia , Dor/induzido quimicamente , Fragmentos de Peptídeos/efeitos adversos , Células Receptoras Sensoriais/citologia , Animais , Bradicinina/farmacologia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Cálcio/metabolismo , Gânglios Espinais/metabolismo , Perfilação da Expressão Gênica , Humanos , Dor/metabolismo , Fragmentos de Peptídeos/farmacologia , Cultura Primária de Células , Ratos , Receptores da Bradicinina/metabolismo , Substância P/metabolismo , Canais de Cátion TRPV/metabolismo , Regulação para Cima/efeitos dos fármacos
6.
Cell Death Discov ; 2: 16050, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551538

RESUMO

A change in the delicate equilibrium between apoptosis and survival regulates the neurons fate during the development of nervous system and its homeostasis in adulthood. Signaling pathways promoting or protecting from apoptosis are activated by multiple signals, including those elicited by neurotrophic factors, and depend upon specific transcriptional programs. To decipher the rescue program induced by substance P (SP) in cerebellar granule neurons, we analyzed their whole-genome expression profiles after induction of apoptosis and treatment with SP. Transcriptional pathways associated with the survival effect of SP included genes encoding for proteins that may act as pharmacological targets. Inhibition of one of these, the Myc pro-oncogene by treatment with 10058-F4, reverted in a dose-dependent manner the rescue effect of SP. In addition to elucidate the transcriptional mechanisms at the intersection of neuronal apoptosis and survival, our systems biology-based perspective paves the way towards an innovative pharmacology based on targets downstream of neurotrophic factor receptors.

7.
Eur Rev Med Pharmacol Sci ; 20(10): 1911-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27249586

RESUMO

OBJECTIVE: Patient satisfaction is the goal of most aesthetic procedures. The aim of this study is to analyse nonsurgical rejuvenation procedures in a private practice setting, over a period of 10 years, evaluating patients' compliance, satisfaction and maintenance of a good fiduciary link with the medical operator. PATIENTS AND METHODS: A retrospective study was performed on 429 patients who received nonsurgical rejuvenation procedures. Four types of treatments were considered: Botulinum toxin type A injections, Hyaluronic acid or Poly-L-lactic acid injections, and a combination therapy. The outcome analyzed included a number of patients for each treatment for each year, the treatment time interval, the number of treatments for each patient, the number of treatments according to facial sub site and the "degree of satisfaction". RESULTS: The most required treatment was combination therapy (36.8% of patients). The mean time and the median time of permanency in the study were respectively 19 and 6 months. After 18 months, which is the time that we considered to attest a good "degree of satisfaction", 55% of patients were still in the study. Patients with only one treatment were excluded. CONCLUSIONS: The study findings support evidence of a more recently described increase in popularity in minimally invasive aesthetic procedures, of which combination therapy has the best performances with a good degree of satisfaction.


Assuntos
Técnicas Cosméticas , Humanos , Satisfação do Paciente , Rejuvenescimento , Estudos Retrospectivos
10.
Hum Mol Genet ; 24(11): 3058-81, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25687137

RESUMO

Disarrangement in functions and quality control of mitochondria at synapses are early events in Alzheimer's disease (AD) pathobiology. We reported that a 20-22 kDa NH2-tau fragment mapping between 26 and 230 amino acids of the longest human tau isoform (aka NH2htau): (i) is detectable in cellular and animal AD models, as well in synaptic mitochondria and cerebrospinal fluids (CSF) from human AD subjects; (ii) is neurotoxic in primary hippocampal neurons; (iii) compromises the mitochondrial biology both directly, by inhibiting the ANT-1-dependent ADP/ATP exchange, and indirectly, by impairing their selective autophagic clearance (mitophagy). Here, we show that the extensive Parkin-dependent turnover of mitochondria occurring in NH2htau-expressing post-mitotic neurons plays a pro-death role and that UCHL-1, the cytosolic Ubiquitin-C-terminal hydrolase L1 which directs the physiological remodeling of synapses by controlling ubiquitin homeostasis, critically contributes to mitochondrial and synaptic failure in this in vitro AD model. Pharmacological or genetic suppression of improper mitophagy, either by inhibition of mitochondrial targeting to autophagosomes or by shRNA-mediated silencing of Parkin or UCHL-1 gene expression, restores synaptic and mitochondrial content providing partial but significant protection against the NH2htau-induced neuronal death. Moreover, in mitochondria from human AD synapses, the endogenous NH2htau is stably associated with Parkin and with UCHL-1. Taken together, our studies show a causative link between the excessive mitochondrial turnover and the NH2htau-induced in vitro neuronal death, suggesting that pathogenetic tau truncation may contribute to synaptic deterioration in AD by aberrant recruitment of Parkin and UCHL-1 to mitochondria making them more prone to detrimental autophagic clearance.


Assuntos
Doença de Alzheimer/genética , Neurônios/metabolismo , Ubiquitina Tiolesterase/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas tau/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Células HeLa , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Mitocondriais/metabolismo , Mitofagia , Neurônios/fisiologia , Transporte Proteico , Ratos Wistar , Proteínas tau/fisiologia
11.
Neurobiol Dis ; 62: 489-507, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24411077

RESUMO

Functional as well as structural alterations in mitochondria size, shape and distribution are precipitating, early events in progression of Alzheimer's Disease (AD). We reported that a 20-22kDa NH2-tau fragment (aka NH2htau), mapping between 26 and 230 amino acids of the longest human tau isoform, is detected in cellular and animal AD models and is neurotoxic in hippocampal neurons. The NH2htau -but not the physiological full-length protein- interacts with Aß at human AD synapses and cooperates with it in inhibiting the mitochondrial ANT-1-dependent ADP/ATP exchange. Here we show that the NH2htau also adversely affects the interplay between the mitochondria dynamics and their selective autophagic clearance. Fragmentation and perinuclear mislocalization of mitochondria with smaller size and density are early found in dying NH2htau-expressing neurons. The specific effect of NH2htau on quality control of mitochondria is accompanied by (i) net reduction in their mass in correlation with a general Parkin-mediated remodeling of membrane proteome; (ii) their extensive association with LC3 and LAMP1 autophagic markers; (iii) bioenergetic deficits and (iv) in vitro synaptic pathology. These results suggest that NH2htau can compromise the mitochondrial biology thereby contributing to AD synaptic deficits not only by ANT-1 inactivation but also, indirectly, by impairing the quality control mechanism of these organelles.


Assuntos
Mitocôndrias/metabolismo , Dinâmica Mitocondrial/fisiologia , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Proteínas tau/metabolismo , Doença de Alzheimer/metabolismo , Linhagem Celular Tumoral , Hipocampo/metabolismo , Hipocampo/ultraestrutura , Humanos , Mitocôndrias/ultraestrutura , Neurônios/ultraestrutura , Sinapses/metabolismo
12.
G Chir ; 33(5): 186-90, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22709457

RESUMO

In recent years, lipofilling has established itself as one of the most effective and least invasive techniques to treat connective dystrophy subsequent to radiotherapy. We report the case of a patient diagnosed with intraductal carcinoma of the right breast in 1996, at the age of 41. The patient underwent quadrantectomy with ipsilateral axillary lymph node dissection and adjuvant chemotherapy and radiotherapy. Four years later, a recurrence led the patient to undergo a subcutaneous mastectomy and immediate reconstruction, involving the submuscular insertion of a permanent implant. In 2007 the patient suffered both radiodermatitis and capsular contracture around the implant, causing constant pain and significant functional limitation. She first took a leukotriene inhibitor (Zafirlukast, 20 mg daily for 8 months) to reduce the capsular contracture. She then underwent lipofilling (Coleman's technique) of the area affected by radiodermatitis, in which the skin was considerably thinned and visibly ischemic. A second session followed four months later. Clinical, photographic and ultrasound examination revealed clear and lasting thickening of the superficial tissues, increased coverage of the implant, and reduced skin discoloration and tension.


Assuntos
Mamoplastia , Radiodermite , Neoplasias da Mama/cirurgia , Humanos , Mastectomia , Recidiva Local de Neoplasia/cirurgia
13.
G Chir ; 33(4): 132-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22668533

RESUMO

INTRODUCTION: Familial Atypical Multiple Mole-Melanoma Syndrome (FAMMM) is an autosomal dominant genodermatosis characterized by the presence of a high number of dysplastic nevi and family history of melanoma or pancreatic cancer. Melanomas in FAMMM patients tend to occur at a younger age, although they are clinically similar to sporadic melanomas in terms of overall survival. CASE REPORT: A 45 year-old woman with a family history of melanoma, a type II phototype and numerous (>100) nevi was admitted to our Department of Dermatology and Plastic Surgery. Over the past years, the patient underwent several surgical operations to remove pigmented lesions and two are dysplastic nevi. Since 1995, she underwent surgery to remove four melanomas. She is followed for skin examinations including dermoscopy. CONCLUSION: Identifying high-risk patients for melanoma represents a primary objective for the specialists that are involved in the management of this disease, especially in order to enact all the necessary surveillance and follow-up strategies.


Assuntos
Melanoma , Neoplasias Primárias Múltiplas , Nevo , Neoplasias Cutâneas , Feminino , Humanos , Melanoma/diagnóstico , Melanoma/cirurgia , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/cirurgia , Nevo/diagnóstico , Nevo/cirurgia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/cirurgia , Síndrome
14.
Neuropharmacology ; 62(5-6): 1954-63, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22244942

RESUMO

Altered levels of Substance P (SP), a neuropeptide endowed with neuroprotective and anti-apoptotic properties, were found in brain areas and spinal fluid of Alzheimer's disease (AD) patients. One of the hallmarks of AD is the abnormal extracellular deposition of neurotoxic beta amyloid (Aß) peptides, derived from the proteolytic processing of amyloid precursor protein (APP). In the present study, we confirmed, the neurotrophic action of SP in cultured rat cerebellar granule cells (CGCs) and investigated its effects on APP metabolism. Incubation with low (5 mM) potassium induced apoptotic cell death of CGCs and amyloidogenic processing of APP, whereas treatment with SP (200 nM) reverted these effects via NK1 receptors. The non-amyloidogenic effect of SP consisted of reduction of Aß(1-42), increase of sAPPα and enhanced α-secretase activity, without a significant change in steady-state levels of cellular APP. The intracellular mechanisms whereby SP alters APP metabolism were further investigated by measuring mRNA and/or steady-state protein levels of key enzymes involved with α-, ß- and γ-secretase activity. Among them, Adam9, both at the mRNA and protein level, was the only enzyme to be significantly down-regulated following the induction of apoptosis (K5) and up-regulated after SP treatment. In addition to its neuroprotective properties, this study shows that SP is able to stimulate non-amyloidogenic APP processing, thereby reducing the possibility of generation of toxic Aß peptides in brain.


Assuntos
Proteínas ADAM/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Cerebelo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Substância P/farmacologia , Proteínas ADAM/genética , Animais , Células Cultivadas , Cerebelo/citologia , Cerebelo/metabolismo , Relação Dose-Resposta a Droga , Neurônios/citologia , Neurônios/metabolismo , Ratos
15.
Int J Immunopathol Pharmacol ; 25(4): 1055-62, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23298495

RESUMO

Human papillomavirus (HPV) is the most common sexually transmitted agent worldwide. Prevalence varies according to the geographic regions, and is highest in developing countries. Geographic differences exist also in the detection rate of oncogenic types in malignant cervical lesions. In this study, the prevalence of HPV infection as well as the spectrum of HPV types was evaluated in Italian and immigrant women of the urban area of Rome. Several risk factors (age at first intercourse, number of partners, smoking, pregnancy, age at first pregnancy, contraception, education, and menarche) were taken into consideration. Overall, there was a high prevalence of HPV infection in the two groups studied. No significant differences were observed in the spectrum of HPV types detected. HPV 16 and 18 were the types detected more frequently in both groups. Interestingly, HPV 54 and 70 were found only in the immigrants. Whether this finding reflects a recent introduction of these HPV types in the population studied remains to be established. Monitoring of HPV types in the population is advisable, especially in countries like Italy which is a destination and a gateway for immigrants directed towards north and central Europe. The introduction of high risk HPV variants may have a clinical impact and affect the diagnostic procedures.


Assuntos
Emigrantes e Imigrantes/estatística & dados numéricos , Infecções por Papillomavirus/epidemiologia , Adolescente , Adulto , Colposcopia , DNA Viral/análise , Feminino , Humanos , Itália/epidemiologia , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Prevalência , Fatores de Risco
16.
Neurobiol Aging ; 32(6): 969-90, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19628305

RESUMO

Alzheimer's disease (AD) is characterized by Aß overproduction and tau hyperphosphorylation. We report that an early, transient and site-specific AD-like tau hyperphosphorylation at Ser262 and Thr231 epitopes is temporally and causally related with an activation of the endogenous amyloidogenic pathway that we previously reported in hippocampal neurons undergoing cell death upon NGF withdrawal [Matrone, C., Ciotti, M.T., Mercanti, D., Marolda, R., Calissano, P., 2008b. NGF and BDNF signaling control amyloidogenic route and Ab production in hippocampal neurons. Proc. Natl. Acad. Sci. 105, 13138-13143]. Such tau hyperphosphorylation, as well as apoptotic death, is (i) blocked by 4G8 and 6E10 Aß antibodies or by specific ß and/or γ-secretases inhibitors; (ii) temporally precedes tau cleavage mediated by a delayed (6-12h after NGF withdrawal) activation of caspase-3 and calpain-I; (iii) under control of Akt-GSK3ß-mediated signaling. Finally, we show that such site-specific tau hyperphosphorylation causes tau detachment from microtubules and an impairment of mitochondrial trafficking. These results depict, for the first time, a rapid interplay between endogenous Aß and tau post-translational modifications which act co-ordinately to compromise neuronal functions in the same neuronal system, under physiological conditions as seen in AD brain.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Neurônios/fisiologia , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/imunologia , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Anticorpos/farmacologia , Transporte Axonal/efeitos dos fármacos , Caspase 3/metabolismo , Morte Celular/genética , Células Cultivadas , Meios de Cultura Livres de Soro/farmacologia , Embrião de Mamíferos , Inibidores Enzimáticos/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Hipocampo/citologia , Humanos , Microtúbulos/metabolismo , Fator de Crescimento Neural/deficiência , Fator de Crescimento Neural/imunologia , Fator de Crescimento Neural/farmacologia , Neurônios/efeitos dos fármacos , Fosforilação/genética , Gravidez , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Sais de Tetrazólio , Tiazóis , Fatores de Tempo , Proteínas tau/genética
17.
Cell Death Differ ; 17(7): 1126-33, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20395961

RESUMO

The term trophic is widely used to indicate a general pro-survival action exerted on target cells by different classes of extracellular messengers, including neurotrophins (NTs), a family of low-molecular-weight proteins whose archetypal member is the nerve growth factor (NGF). The pro-survival action exerted by NTs results from a coordinated activation of multiple metabolic pathways, some of which have only recently come to light. NGF has been shown to exert a number of different, experimentally distinguishable effects on neurons, such as survival, differentiation of target neurons, growth of nerve fibers and their guidance (tropism) toward the source of its production. We have proposed a more complete definition of the NGF trophic action that should also include its newly discovered property of inhibiting the amyloidogenic processing of amyloid precursor protein (APP), which is among the first hypothesized primary trigger of Alzheimer's disease (AD) pathogenesis. This inhibitory action appears to be mediated by a complex series of molecular events and by interactions among NGF receptors (TrkA and p75), APP processing and tau metabolic fate and function.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Fator de Crescimento Neural/metabolismo , Doença de Alzheimer/metabolismo , Animais , Apoptose , Fator de Crescimento Neural/farmacologia , Fatores de Crescimento Neural/farmacologia , Neurônios/citologia , Neurônios/metabolismo , Ratos , Receptor trkA/metabolismo , Receptor trkA/fisiologia
18.
Neuropharmacology ; 58(1): 268-76, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19576909

RESUMO

The tachykinin endecapeptide substance P (SP) has been demonstrated to exert a functional role in neurodegenerative disorders, including Alzheimer's disease (AD). Aim of the present study was to evaluate the SP neuroprotective potential against apoptosis induced by the neurotoxic beta-amyloid peptide (A beta) in cultured rat cerebellar granule cells (CGCs). We found that SP protects CGCs against both A beta(25-35)- and A beta(1-42)-induced apoptotic CGCs death as revealed by live/dead cell assay, Hoechst staining and caspase(s)-induced PARP-1 cleavage, through an Akt-dependent mechanism. Since in CGCs the fast inactivating or A-type K(+) current (I(KA)) was potentiated by A beta treatment through up-regulation of Kv4 subunits, we investigated whether I(KA) and the related potassium channel subunits could be involved in the SP anti-apoptotic activity. Patch-clamp experiments showed that the A beta-induced increase of I(KA) current amplitude was reversed by SP treatment. In addition, as revealed by Western blot analysis and immunofluorescence studies, SP prevented the up-regulation of Kv4.2 and Kv4.3 channel subunits expression. These results indicate that SP plays a role in the regulation of voltage-gated potassium channels in A beta-mediated neuronal death and may represent a new approach in the understanding and treatment of AD.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Cerebelo/citologia , Neurônios/efeitos dos fármacos , Canais de Potássio Shal/metabolismo , Substância P/farmacologia , Animais , Animais Recém-Nascidos , Biofísica , Caspase 3/metabolismo , Células Cultivadas , Estimulação Elétrica , Ativação do Canal Iônico/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Proteína Oncogênica v-akt/metabolismo , Técnicas de Patch-Clamp/métodos , Fragmentos de Peptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Canais de Potássio Shal/efeitos dos fármacos
19.
Euro Surveill ; 14(49)2009 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-20003903

RESUMO

The serological status of hepatitis viruses and other infectious diseases in the 66 dialysed patients of one haemodialysis unit in Kosovo were studied, comparing the data with a large group of blood donors and out-patients. All dialysed patients were hepatitis A virus (HAV) positive. Prevalence of hepatitis B surface antigen (HBsAg), hepatitis B surface antibodies (anti-HBs), and hepatitis B core antibodies (anti-HBc) was 14 of 66, 21% (95% confidence interval (CI): 12-33%), 5 of 66, 8% (95%CI: 5-22%), and 50 of 66, 76% (95%CI: 64-85%), respectively. Antibodies to hepatitis C virus (anti-HCV) prevalence was 57 of 66, 86% (95%CI: 76-94%). No human immunodeficiency virus (HIV) positive case was found. Prevalence of past herpes simplex virus type 2 (HSV-2) infection was 29% (95%CI: 18-41%). Two patients (3%, 95%CI: 0-10%) were positive for Treponema pallidum and 18% (95%CI: 10-30%) were human herpesvirus 8 (HHV-8) antibody positive. Four hundred and fifty-two subjects were recruited for comparison. Markers of past HAV infection was associated with haemodialysis (Fisher s exact test p-value=0.037). Dialysed patients were at a higher risk of being HBsAg positive than others: the sex- and age-adjusted odds ratio (OR) was 5.18 (95%CI: 1.87-14.32). Anti-HBc positivity was strongly associated with haemodialysis: the sex- and age-adjusted OR was 6.43 (95%CI: 3.22-12-85). Anti-HCV positivity was 86% and 1% in presence and absence of haemodialysis, respectively. The Fisher s exact test for association proved a strong association between haemodialysis and HCV (p-value<0.0001). The OR for association between haemodialysis and HSV-2 positivity was 3.20 (95%CI: 1.46-7.00). Significant associations were also observed between haemodialysis status and antibodies to Treponema pallidum (Fisher s exact test p-value=0.044). In Kosovo, the prevalence of viral hepatitis infection and other viral infections and Treponema pallidum among dialysed patients is high, indicating major ongoing nosocomial transmission.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Infecções por HIV/epidemiologia , Hepatite Viral Humana/epidemiologia , Diálise Renal/estatística & dados numéricos , Infecções por Treponema/epidemiologia , Adulto , Comorbidade , Feminino , Humanos , Incidência , Masculino , Vigilância da População , Medição de Risco , Fatores de Risco , Iugoslávia/epidemiologia
20.
Proc Natl Acad Sci U S A ; 106(27): 11358-63, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19549834

RESUMO

The present study shows that increased Abeta production in hippocampal neurons, due to a failure of NGF signal, induces an unexpected phosphorylation of tyrosine kinase receptor A (TrkA), followed by activation of the phospholipase C gamma (PLCgamma) pathway and neuronal death. Such phosphorylation seems causally connected with 2 kinases known be involved in amyloidogenesis, Src and CDK5, and associated with alpha and gamma secretase-mediated p75 processing. Pharmacologic inhibition of TrkA phosphorylation and partial silencing of TrkA and/or p75 receptors prevent PLCgamma activation and protect neurons from death. Concomitantly with these events, TrkA, p75, Abeta peptides, and PS1 protein coimmunoprecipitate, suggesting their direct interplay in the subsequent onset of apoptotic death. Together, these findings depict a cellular mechanism whereby the same cellular transducing system may invert its intracellular message from trophic and antiapoptotic to a death signaling, which could also have relevance in the onset of Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Apoptose , Receptor trkA/metabolismo , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Núcleo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quinase 5 Dependente de Ciclina/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Hipocampo/citologia , Imunoprecipitação , Fator de Crescimento Neural/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Fosfolipase C gama/metabolismo , Fosforilação/efeitos dos fármacos , Presenilina-1/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Quinases da Família src/metabolismo
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