RESUMEN
Due to its almost universal resistance to chemotherapy, metastasized melanoma remains a major challenge in clinical oncology. Given that phosphatidyl inositol-3 kinase (PI3K) activation in melanoma cells is associated with poor prognosis, disease progression and resistance to chemotherapy, the PI3K-Akt signalling pathway is a promising therapeutic target for melanoma treatment. We analysed six human melanoma cell lines for their constitutive activation of Akt and then tested two representative lines, A375 and LOX, for their susceptibility to PI3K-inhibition by the highly specific small molecule inhibitor, BAY 80-6946. In addition, the effect of BAY 80-6946 on A375 and LOX melanoma cells was assessed in vivo in a xenotransplantation mouse model. We provide experimental evidence that specifically inhibiting the PI3K pathway and phosphorylation of Akt by this novel compound results in antitumoral activities including inhibition of proliferation, induction of apoptosis and cell cycle arrest in vitro and in vivo. However, the susceptibility did not show a clear-cut pattern and differed between the melanoma cell lines tested, resulting in in vivo growth inhibition of A375 but not LOX melanoma cells. Thus, in some cases BAY 80-6946 or related compounds may be a valuable addition to the therapeutic armamentarium.
Asunto(s)
Proliferación Celular/efectos de los fármacos , Melanoma/patología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Pirimidinas/farmacología , Quinazolinas/farmacología , Neoplasias Cutáneas/patología , Animales , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Células Cultivadas , Inhibidores Enzimáticos/farmacología , Humanos , Técnicas In Vitro , Melanoma/metabolismo , Melanoma/fisiopatología , Ratones , Ratones Desnudos , Fosfatidilinositol 3-Quinasas/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/fisiopatología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: To date, elective nephron-sparing surgery is an established method for the exstirpation of renal tumors. While open partial nephrectomy remains the reference standard of the management of renal masses, laparoscopic partial nephrectomy (LPN) continues to evolve. Conventional techniques include clamping the renal vessels risking ischaemic damage of the clamped organ. Thus, new techniques are needed that combine a sufficient tissue incision for exstirpation of the tumor with an efficient coagulation to assure haemostasis and abandon renal vessel clamping in LPN. Laser-excision of renal tumors during laparoscopic surgery seems to be a logical solution. METHODS: We performed nephron-sparing surgery without clamping of the renal vessels in 11 patients with a renal tumor in exophytic position (mean size 32 mm, ranging 8-45 mm) by laser-supported LPN. RESULTS: Regular ultrasound monitoring and insertion of a temporary drainage showed no evidence of postoperative hemorrhage. All tumors were removed with a histopathologically confirmed surrounding margin of normal renal tissue (R0 resection). Serum creatinine, hemoglobin, and hematocrit were nearly unaltered before and after surgery. CONCLUSIONS: The experience won in these patients have confirmed that laser-assisted LPN without clamping of the renal vessels could be a safe and gentle alternative to classic partial nephrectomy in patients with exophytic position of renal tumors.
Asunto(s)
Carcinoma de Células Renales/cirugía , Neoplasias Renales/cirugía , Laparoscopía/métodos , Terapia por Láser/métodos , Nefrectomía/métodos , Adulto , Anciano , Carcinoma de Células Renales/diagnóstico , Terapia Combinada , Femenino , Hemostasis Quirúrgica , Humanos , Neoplasias Renales/diagnóstico , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Recent studies have shown that patients with Alzheimer's disease (AD) and its possible prodromal stage mild cognitive impairment benefit from cognitive interventions. Few studies so far have used an active control condition and determined effects in different stages of disease. We evaluated a newly developed 6-month group-based multicomponent cognitive intervention in a randomized controlled pilot study on subjects with amnestic mild cognitive impairment (aMCI) and mild AD patients. Forty-three subjects with aMCI and mild AD were recruited. Primary outcome measures were change in global cognitive function as determined by the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) and the Mini Mental Status Examination (MMSE). Secondary outcomes were specific cognitive and psychopathological ratings. Thirty-nine patients were randomized to intervention groups (IGs: 12 aMCI, 8 AD) and active control groups (CGs: 12 aMCI, 7 AD). At the end of the study, we found significant improvements in the IG(MCI) compared to the CG(MCI) in the ADAS-cog (p = 0.02) and for the secondary endpoint Montgomery Asberg Depression Rating Scale (MADRS) (p < 0.01) Effects on the MMSE score showed a non-significant trend (p = 0.07). In AD patients, we found no significant effect of intervention on the primary outcome measures. In conclusion, these results suggest that participation in a 6-month cognitive intervention can improve cognitive and non-cognitive functions in aMCI subjects. In contrast, AD patients showed no significant benefit from intervention. The findings in this small sample support the use of the intervention in larger scales studies with an extended follow-up period to determine long-term effects.
Asunto(s)
Enfermedad de Alzheimer/terapia , Amnesia/terapia , Terapia Cognitivo-Conductual , Disfunción Cognitiva/terapia , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Amnesia/psicología , Disfunción Cognitiva/psicología , Interpretación Estadística de Datos , Estudios de Factibilidad , Femenino , Objetivos , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Aceptación de la Atención de Salud , Proyectos Piloto , Índice de Severidad de la Enfermedad , Factores Socioeconómicos , Resultado del TratamientoRESUMEN
BACKGROUND: Hypertension is a major risk factor of Alzheimer's disease (AD); however, controlled studies on the effect of antihypertensive treatment on the risk of dementia are inconclusive. Therefore, a biological marker that predicts individual response to antihypertensive treatment would be of high clinical relevance. Midregional proatrial natriuretic peptide (MR-proANP), an inactive surrogate molecule of the mature atrial natriuretic peptide, is related to circulatory function and hypertension. METHODS: A sample population of 134 subjects with mild cognitive impairment (MCI) was followed for up to 6 years. Multivariable Cox regression analysis was conducted to predict conversion to AD based on all relevant variables. RESULTS: Baseline MR-proANP was significantly increased in the AD converter group (p < .0001). The conversion rate of patients treated with antihypertensive drugs was significantly reduced only in patients with elevated MR-proANP at baseline (p = .046). Using an optimized MR-proANP cutoff of 74 pmol/L, representing a value in the upper normal range, treatment with antihypertensive drugs reduced the conversion rate to AD by 36% (p = .035) for patients with levels >74 pmol/L. Further subgrouping by age (>/≤ 72 years at baseline) increased the positive correlation of antihypertensive treatment and MCI outcome for patients below the age of 72 years (conversion rate reduced by 74%, p = .016). CONCLUSIONS: These data seem to support the notion of a potential impact of circulatory function for the prognosis of AD at a prodromal stage. The MR-proANP levels may be useful to predict the effect of antihypertensive treatment on conversion rates to AD in subjects with MCI.
Asunto(s)
Enfermedad de Alzheimer/etiología , Antihipertensivos/efectos adversos , Factor Natriurético Atrial/metabolismo , Trastornos del Conocimiento/metabolismo , Trastornos del Conocimiento/fisiopatología , Anciano , Presión Sanguínea/efectos de los fármacos , Progresión de la Enfermedad , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Estimación de Kaplan-Meier , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Análisis de Regresión , Estudios RetrospectivosRESUMEN
At the earliest clinical stages of Alzheimer's disease (AD), when first symptoms are mild, making a reliable and accurate diagnosis is difficult. AD related brain pathology and underlying molecular mechanisms precede symptoms. Biological markers can serve as supportive early screening and diagnostic tools as well as indicators of presymptomatic biochemical change. Moreover, biomarkers cover a variety of roles and functions such as disease prediction, indicating disease acuity and progression, and may ensure biological mapping of treatment outcome. Early screening, detection, and diagnosis of AD would permit earlier disease modifying intervention at potentially reversible stages. To date, most established biological markers from both cerebrospinal fluid neurochemistry and structural and functional neuroimaging have not reached widespread clinical application. Crucial remaining problems, such as easy acceptance and application of a test, cost-effectiveness, and noninvasiveness, need to be resolved. The development and validation of precise, reliable, and robust tests and biomarkers in blood, plasma, or serum has therefore been for a long time the ultimate focus of many research groups worldwide. Blood-based testing will most likely be the prerequisite to future sensitive screening of large populations at risk of AD and the baseline in a diagnostic flow approach to AD. The status and emerging perspectives on hypothesis and exploratory-based candidate biomarkers derived from blood, plasma, and serum are reviewed and discussed.
Asunto(s)
Enfermedad de Alzheimer/sangre , Biomarcadores/sangre , Plasma/metabolismo , Suero/metabolismo , Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/sangre , Péptidos beta-Amiloides/inmunología , Precursor de Proteína beta-Amiloide/sangre , Animales , Apolipoproteínas E/sangre , Autoanticuerpos/sangre , Colesterol/metabolismo , Humanos , Proteínas tau/sangreRESUMEN
OBJECTIVES: To define and discuss reference ranges for commonly determined laboratory parameters in healthy adults from southern Tanzania. METHODS: A population-based sample of adult volunteers from Mbeya, Tanzania, who were not HIV positive or showing signs and symptoms of other diseases, participated in this study. We enrolled 145 women and 156 men between 19 and 48 years of age to determine clinical chemistry (CC), haematology and lymphocyte immunophenotyping (LIP) parameters using standard laboratory methods. Medians and nonparametric 95% reference ranges for each parameter were determined and compared with reference ranges from the USA, Europe and from other African countries. RESULTS: Agreement with ranges from developed countries was poor: for CC values the average concordance was 80.9% and 86.7% with values from two developed countries. Haematology ranges from the USA classified 86.3% of values correctly, whereas ranges from three different sub-Saharan Africa (SSA) sites classified between 82.5% and 94.5% of values correctly. The agreement of LIP reference ranges was 87.5% with values determined in Germany but between 91.7% and 95.8% compared with values determined at other sites in SSA. CONCLUSION: Clinical reference ranges determined in developed countries are inadequate for use in SSA. Laboratories in this region should either define their own or use values determined under similar conditions. The ranges reported here are more appropriate for use in SSA than ranges determined in developed countries.