Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
1.
J Neurol Sci ; 464: 123147, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39094432

RESUMO

BACKGROUND: Increasing evidence indicates a metabolic etiology for migraines, with ketosis potentially rectifying metabolic and clinical features. We conducted a pilot study to evaluate CER-0001, a ketogenic agent, for migraine prevention without dietary changes. METHODS: This was a 2-part, double-blind, randomised, placebo-controlled study conducted in Australia. Adults with at least a 1-year history of migraine and ≥ 1 prior preventive treatment failure were randomised to either oral CER-0001 (up to 30 g twice a day) or placebo for 12 weeks. The primary endpoint was Month 3 change in Migraine Headache Days from baseline. RESULTS: Part 1 results are presented. 81 participants were randomised and dosed (n = 40 CER-0001, n = 41 placebo), and 61 participants had evaluable efficacy data. No statistically significant difference was observed in the primary endpoint (LSMean difference 0.92 days; p = 0.586). During Month 2, a mean improvement of -2.8 days was observed for CER-0001 (p = 0.056). Withdrawal rates were 45.0% and 53.7% (CER-0001; placebo). The proportion of participants reporting at least one treatment-emergent adverse event was similar between arms (90.0% CER-0001, 82.9% placebo), mostly gastrointestinal (85.0% CER-0001, 70.7% placebo). CONCLUSION: Results suggest positive directional promise over 2-3 months for CER-0001. A new formulation will be used for larger, fully powered phase 2/3 studies. TRIAL REGISTRATION: This study is registered at ClinicalTrials.gov (NCT04437199).


Assuntos
Transtornos de Enxaqueca , Humanos , Masculino , Feminino , Método Duplo-Cego , Projetos Piloto , Transtornos de Enxaqueca/prevenção & controle , Transtornos de Enxaqueca/tratamento farmacológico , Adulto , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
2.
Science ; 385(6706): 300-304, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39024448

RESUMO

Dielectric materials are foundational to our modern-day communications, defense, and commerce needs. Although dielectric breakdown is a primary cause of failure of these systems, we do not fully understand this process. We analyzed the dielectric breakdown channel propagation dynamics of two distinct types of electrical trees. One type of these electrical trees has not been formally classified. We observed the propagation speed of this electrical tree type to exceed 10 million meters per second. These results identify substantial gaps in the understanding of dielectric breakdown, and filling these gaps is paramount to the design and engineering of dielectric materials that are less susceptible to electrostatic discharge failure.

4.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117194

RESUMO

Dielectric breakdown is an example of a natural phenomenon that occurs on very short time scales, making it incredibly difficult to capture optical images of the process. Event initiation jitter is one of the primary challenges, as even a microsecond of jitter time can cause the imaging attempt to fail. Initial attempts to capture images of dielectric breakdown using a gigahertz frame rate camera and an exploding bridge wire initiation were stymied by high initiation jitter. Subsequently, a novel optical delay line apparatus was developed in order to effectively circumvent the jitter and reliably image dielectric breakdown. The design and performance of the optical delay line apparatus are presented. The optical delay line increased the image capture success rate from 25% to 94% while also permitting enhanced temporal resolution and has application in imaging other high-jitter, extremely fast phenomena.

6.
Methods Mol Biol ; 2660: 311-344, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37191807

RESUMO

Organoids have emerged as a promising advancement of the two-dimensional (2D) culture systems to improve studies in organogenesis, drug discovery, precision medicine, and regenerative medicine applications. Organoids can self-organize as three-dimensional (3D) tissues derived from stem cells and patient tissues to resemble organs. This chapter presents growth strategies, molecular screening methods, and emerging issues of the organoid platforms. Single-cell and spatial analysis resolve organoid heterogeneity to obtain information about the structural and molecular cellular states. Culture media diversity and varying lab-to-lab practices have resulted in organoid-to-organoid variability in morphology and cell compositions. An essential resource is an organoid atlas that can catalog protocols and standardize data analysis for different organoid types. Molecular profiling of individual cells in organoids and data organization of the organoid landscape will impact biomedical applications from basic science to translational use.


Assuntos
Organoides , Medicina Regenerativa , Humanos , Células-Tronco , Organogênese , Análise Espacial
7.
Eur J Pharm Biopharm ; 182: 41-52, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36470522

RESUMO

At present, tricaprilin is used as a ketogenic source for the management of mild to moderate Alzheimer's disease. After administration of the medium-chain triglyceride, tricaprilin is hydrolyzed to octanoic acid and further metabolized to ketones, acting as an alternative energy substrate for the brain. In this investigation, we developed a physiologically-based biopharmaceutics model simulating in vivo processes following the peroral administration of tricaprilin. The model includes multiple data sources to establish a partially verified framework for the simulation of plasma profiles. The input parameters were identified based on existing literature data and in vitro digestion studies. Model validation was conducted using the data from a phase I clinical trial. A partial parameter sensitivity analysis elucidated various influences on the plasma ketone levels that are mainly responsible for the therapeutic effects of tricaprilin. Based on our findings, we concluded that dispersibility and lipolysis of tricaprilin together with the gastric emptying patterns are limiting ketogenesis, while other steps such as the conversion of octanoic acid to ketone bodies play a minor role only.


Assuntos
Corpos Cetônicos , Cetonas , Humanos , Administração Oral , Digestão , Corpos Cetônicos/metabolismo , Triglicerídeos
8.
J Alzheimers Dis ; 75(2): 547-557, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32310169

RESUMO

BACKGROUND: Alzheimer's disease (AD) is characterized by amyloid-ß plaques, neurofibrillary tangles, and regional cerebral glucose hypometabolism. Providing an alternative metabolic substrate, such as ketone bodies, may be a viable therapeutic option. OBJECTIVE: The objective was to determine the efficacy and safety of the AC-1204 formulation of caprylic triglyceride administered daily for 26 weeks in APOE4 non-carrier participants with mild-to-moderate AD. METHODS: In a double-blind, placebo-controlled, randomized study (AC-12-010, NOURISH AD, NCT01741194), 413 patients with mild-to-moderate probable AD were stratified by APOE genotype and randomized (1 : 1) to receive either placebo or AC-1204 for 26 weeks. The primary outcome was the change from baseline to week 26 on the 11-item Alzheimer's Disease Assessment Scale - Cognitive subscale (ADAS-Cog11) among APOE4 non-carriers. The key secondary outcome was the change from baseline to week 26 in the Alzheimer's Disease Cooperative Study - Clinician's Global Impression of Change scale. RESULTS: Administration of AC-1204 was safe and well-tolerated. Mean changes from baseline in the primary outcome at 26 weeks in ADAS-Cog11 for placebo (n = 138) was 0.0 and for AC-1204 (n = 137) was 0.6 (LS differences of mean - 0.761, p = 0.2458) and secondary outcome measures failed to detect any drug effects. CONCLUSION: The AC-1204 formulation of caprylic triglyceride failed to improve cognition or functional ability in subjects with mild-to-moderate AD. The lack of efficacy observed in this study may have several contributing factors including a lower ketone body formation from AC-1204 than expected and a lack of decline in the patients receiving placebo.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Cognição/efeitos dos fármacos , Triglicerídeos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Resultado do Tratamento , Triglicerídeos/administração & dosagem
10.
Ann Surg Oncol ; 25(3): 801-807, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29218429

RESUMO

BACKGROUND: Adrenocortical carcinoma (ACC) has a poor prognosis and there is an unmet clinical need for biomarkers to improve both diagnostic and prognostic assessment. Pituitary-tumor transforming gene (PTTG1) has been shown to modulate cancer invasiveness and response to therapy. The potential role of PTTG1 protein levels in ACC has not been previously addressed. We assessed whether increased nuclear protein expression of PTTG1 distinguished ACCs from adrenocortical adenomas (ACAs). METHODS: Patients with ACC or ACA were identified from prospective tissue banks at two independent institutions. Two tissue microarrays (TMAs) consisting of adrenal specimens from 131 patients were constructed and clinically annotated. Immunohistochemical analysis for PTTG1 and Ki-67 was performed on each TMA. RESULTS: TMA-1 (n = 80) contained 20 normal adrenals, 20 ACAs, and 40 ACCs, and the validation, TMA-2 (n = 51), consisted of 10 normal adrenals, 14 ACAs, and 27 ACCs. On TMA-1, nuclear staining of PTTG1 was detected in 12 (31%) ACC specimens, while all ACAs and normal adrenal glands were negative for PTTG1. On TMA-2, 20 (74%) of the ACC tumors demonstrated PTTG1 nuclear staining of PTTG1, and 13 (93%) ACA and 4 (44%) normal adrenal glands were negative for PTTG1. ACC tumors with increased PTTG1 protein staining had a significantly higher Ki-67 index (p < 0.001) than those with lower levels of PTTG1. CONCLUSIONS: Increased nuclear protein expression of PTTG1 was observed in malignant adrenal tumors. PTTG1 correlated with Ki-67 in two independent TMAs. PTTG1 is a promising biologic marker in the evaluation of adrenal tumors.


Assuntos
Neoplasias do Córtex Suprarrenal/diagnóstico , Glândulas Suprarrenais/patologia , Adenoma Adrenocortical/diagnóstico , Carcinoma Adrenocortical/diagnóstico , Biomarcadores Tumorais/metabolismo , Securina/metabolismo , Neoplasias do Córtex Suprarrenal/metabolismo , Glândulas Suprarrenais/metabolismo , Adenoma Adrenocortical/metabolismo , Carcinoma Adrenocortical/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Adulto Jovem
11.
J Environ Radioact ; 173: 85-96, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27979647

RESUMO

Bioaccessible U, Th, Pb and the 238U decay products 214Pb and 210Pb have been determined, using a modified Unified BARGE Method (UBM), in waste solids and soils from an abandoned uranium mine in South West England, UK. Maximum aqua regia extractable concentrations for U, Th and Pb were 16,200, 3.8 and 4750 µg g-1, respectively. 238U had highest activity concentrations near the mine shaft, where the decay products214Pb and 210Pb had values of 235 and 180 Bq g-1, respectively. UBM extractions gave mean gastro-intestinal bioaccessibility factors (BAFs) for U and Pb in the waste solids of 0.05 and 0.03, respectively, whereas those for the soils were significantly higher at 0.24 and 0.17. The mean BAFs for the transient radionuclides, 214Pb and 210Pb, were similar to those for stable Pb implying that the stable and radioactive Pb isotopes were attached to similar sites on the particles. The doses arising from the ingestion of particulate 210Pb due to soil pica behaviour were in the range 0.2-65 and < 0.1-6.2 µSv day-1 for a 1-year old child or an adult (>17 years), respectively. The results suggest that the health risk posed by abandoned uranium mines, with waste rock and tailings, throughout the world should take account of the dose due to both bioaccessible radionuclides, as well as their stable counterparts.


Assuntos
Radioisótopos de Chumbo/análise , Mineração , Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise
12.
J Urol ; 193(4): 1129-34, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25254936

RESUMO

PURPOSE: While many urologists recommend radical cystectomy for micropapillary bladder cancer invading the lamina propria (cT1), contradictory small reports exist on the efficacy of conservative management with intravesical bacillus Calmette-Guérin for this disease. We report our updated experience in what to our knowledge is the largest series of patients with cT1 micropapillary bladder cancer. MATERIALS AND METHODS: An institutional review board approved review of our cancer database identified 283 patients with micropapillary bladder cancer, including 72 staged with cT1N0M0 disease at diagnosis and initiation of therapy. Survival analysis was performed using the Kaplan-Meier estimator and compared using the log rank test. RESULTS: In this cohort of 72 patients 40 received primary intravesical bacillus Calmette-Guérin and 26 underwent up-front radical cystectomy. Of patients who received bacillus Calmette-Guérin 75%, 45% and 35% experienced disease recurrence, progression and lymph node metastasis, respectively. Patients treated with up-front cystectomy had improved survival compared to patients treated with primary bacillus Calmette-Guérin (5-year disease specific survival 100% vs 60% p = 0.006) and patients who underwent delayed cystectomy after recurrence (5-year disease specific survival 62%, p = 0.015). Prognosis was especially poor in patients who waited for progression before undergoing radical cystectomy with an estimated 5-year disease specific survival of only 24% and a median survival of 35 months. In patients treated with up-front cystectomy pathological up-staging was found in 27%, including 20% with lymph node metastasis. CONCLUSIONS: While certain patients with T1 micropapillary bladder cancer may respond to intravesical bacillus Calmette-Guérin, survival is improved in those who undergo early radical cystectomy. Further molecular studies are needed to identify subsets of patients in whom the bladder can be safely spared.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Vacina BCG/uso terapêutico , Carcinoma Papilar/tratamento farmacológico , Carcinoma Papilar/cirurgia , Cistectomia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/cirurgia , Idoso , Carcinoma Papilar/mortalidade , Carcinoma Papilar/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
13.
J Cutan Pathol ; 41(11): 846-52, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25263506

RESUMO

BACKGROUND: High mitotic figure count (MFC) correlates with low survival rate in Merkel cell carcinoma (MCC). However, the prognostic impact of histone biomarkers as surrogates of MFC in MCC is unknown. We evaluated the prognostic significance of the immunodetection of mitotic figures and of G2+ tumor nuclei with histone-associated mitotic markers H3K79me3T80ph (H3KT) and phosphohistone H3 (PHH3) in MCC. METHODS: Immunohistochemical analyses of H3KT and PHH3 and proliferative marker Ki-67 were performed in a series of 21 cases of MCC. The significance of the pathologic data and immunoreactivity with these markers was evaluated with Pearson correlation and paired Student t-test. Univariate Cox proportional hazards regression models were performed to assess the relationships between these markers and survival. RESULTS: H3KT detected a higher number of mitotic figure (p<0.0001) and G2+ tumor nuclei (p<0.0052) than did PHH3. Furthermore, the MFC combined with G2+ tumor nuclei detected with H3KT compared to PHH3 and manual MFC was a significant predictor of impaired survival in patients with MCC (p=0.035; HR=1.0172), corresponding to a 1.72% increased risk of death for each unit increase in H3KT. CONCLUSIONS: Biomarker analysis of proliferative rates with histone markers may have relevance in stratifying risk in patients with MCC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Célula de Merkel/patologia , Núcleo Celular/patologia , Histonas/análise , Neoplasias Cutâneas/patologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Célula de Merkel/mortalidade , Proliferação de Células , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mitose , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Cutâneas/mortalidade
14.
Am J Surg Pathol ; 38(8): 1102-10, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25029117

RESUMO

Poorly differentiated, cytologically malignant, spindle cell neoplasms of the skin may present a diagnostic challenge with important clinical consequences. In particular, the distinction between poorly differentiated cutaneous spindle cell squamous cell carcinoma (SpSCC) and atypical fibroxanthoma (AFX) remains controversial, but with important clinical implications: SpSCC exhibits an increased tendency for both local recurrence and metastasis compared with AFX. AFX is generally accepted as a diagnosis of exclusion based on negativity for a broad panel of immunohistochemical markers, including multiple cytokeratins, melanocytic markers, muscle markers, and vascular markers. As cytokeratins can also be occasionally lost in SpSCC, it would be of tremendous diagnostic value if there were additional specific markers to facilitate the distinction of lineage in this differential diagnostic context. Initial studies demonstrated p63 to be of utility in distinguishing AFX from SpSCC; however, p63 has proved to lack specificity, as it also exhibits variable reactivity in a subset of AFX. Recent studies have shown p40 immunohistochemistry to be a more specific marker than p63 for the designation of squamous differentiation in carcinomas involving other organ systems. In the current study, we define the utility of p40 immunohistochemistry among common cutaneous spindle cell malignancies, and, specifically, we compare the diagnostic accuracy of p40 and p63 in distinguishing AFX from SpSCC. We show that p40 and p63 exhibit comparable sensitivity, but p40 exhibits superior specificity in the distinction of AFX from SpSCC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/diagnóstico , Histiocitoma Fibroso Benigno/diagnóstico , Epitopos Imunodominantes/análise , Proteínas de Membrana/análise , Fragmentos de Peptídeos/análise , Neoplasias Cutâneas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Carcinoma de Células Escamosas/metabolismo , Feminino , Histiocitoma Fibroso Benigno/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Neoplasias Cutâneas/metabolismo
15.
BMJ Case Rep ; 20132013 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-23784764

RESUMO

Metastasis to the adrenal can be seen in the context of metastatic melanoma, but primary adrenal melanoma is very uncommon. We present a case of a rapidly enlarging adrenal mass that mimicked non-functioning primary adrenal malignancies but later proved to be part of a widely metastatic melanoma of unknown primary origin. Careful physical examination of the patient led to the discovery of a subcutaneous metastatic focus that was not seen on [(18)F]-fluorodeoxyglucose positron emission tomography/CT imaging. The presence of subcutaneous metastases raised the suspicion for metastatic melanoma; however, pathological confirmation remained the ultimate tool to reach the final diagnosis.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Melanoma/diagnóstico , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Neoplasias das Glândulas Suprarrenais/patologia , Idoso , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Terapia Combinada , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Diagnóstico Diferencial , Feminino , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Metástase Neoplásica , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Neoplasias Primárias Desconhecidas/patologia , Radiocirurgia , Temozolomida , Tomografia Computadorizada por Raios X
16.
BMC Med Genet ; 12: 137, 2011 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-21992747

RESUMO

BACKGROUND: To examine the effect of genetic variation in APOE, IDE and IL1B on the response to induced ketosis in the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) in subjects with mild to moderate Alzheimer's disease (AD). METHODS: Genotype effects on ADAS-Cog scores from a randomized, double-blind, placebo-controlled study in mild to moderate AD were examined by an overall two way analysis of variance. In addition, interactions with the carriage status of the epsilon 4 allele of the APOE gene (APOE4) were examined. RESULTS: Significant differences in response to induced ketosis were found among non-carriers of putative gain-of-function polymorphisms in rs1143627 and rs16944 in the IL1B gene and among variants of the polymorphism rs2251101 in the IDE gene. Significant differences were found among non-carriers of the APOE4 gene, with notable improvement among the E3/E3 genotype group. CONCLUSIONS: Variants in APOE, IL1B and IDE may influence the cognitive response to induced ketosis in patients with mild to moderate AD. TRIAL REGISTRATION: This trial was registered with ClinicalTrials.gov, registry number NCT00142805.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Apolipoproteína E3/genética , Apolipoproteína E4/genética , Transtornos Cognitivos/tratamento farmacológico , Insulisina/genética , Interleucina-1beta/genética , Corpos Cetônicos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Transtornos Cognitivos/genética , Método Duplo-Cego , Feminino , Humanos , Masculino , Polimorfismo Genético , Índice de Gravidade de Doença
17.
Am J Med Genet A ; 149A(11): 2507-12, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19876903

RESUMO

Partial trisomy 2p is typically associated with partial monosomy of another chromosomal segment and results from a balanced translocation in one of the parents. Inverted duplications with terminal deletions have been reported in an increasing number of chromosomes. Several cases initially interpreted as terminal duplications have instead been documented to represent inverted duplications with terminal deletions. Inv dup del(2p) has been reported in patients who manifest the clinical findings of trisomy 2p syndrome. Here we report on a 2-month-old girl with inv dup del(2p) and clinical manifestations that overlap those found commonly in partial 2p trisomy, as previously reported in the literature. Her clinical picture helps delineate the phenotype of 2p duplication disorders.


Assuntos
Deleção Cromossômica , Inversão Cromossômica/genética , Cromossomos Humanos Par 2/genética , Análise Citogenética/métodos , Duplicação Gênica , Trissomia/genética , Bandeamento Cromossômico , Cromossomos Artificiais Bacterianos/genética , Hibridização Genômica Comparativa , Evolução Fatal , Feminino , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Gravidez
18.
J Assoc Genet Technol ; 35(3): 88-92, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19738329

RESUMO

The t(8;21)/RUNX1-RUNX1T1 is found in ~5 percent of cases of acute myeloid leukemia (AML) and in 10 percent of the prior AML with maturation (M2) category of the French-American-British (FAB) classification. While AML with t(8;21) is considered a distinct entity with a favorable prognosis, the clinical consequence of variant translocations is less well defined. In this report we described a 45 year-old male patient having a diagnosis of AML-M2 with morphologic and immunophenotypic features suggestive of t(8;21). However, the initial karyotypic analysis revealed an apparently balanced translocation between 1p36 and 8q22. Further fluorescence in situ hybridization (FISH) studies using the AML1/ETO and the p58 probes from Abbott Molecular, demonstrated a three-way translocation between chromosomes 1, 21, and 8, with single fusion of RUNX1-RUNX1T1 on the derivative chromosome 8 [t(1;21;8)(p36.1;q22;q22)]. The patient was in complete remission after induction therapy followed by consolidation. This report demonstrates the importance of FISH studies for detection of cryptic specific chromosome rearrangements that may have prognostic significance.

19.
Nutr Metab (Lond) ; 6: 31, 2009 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-19664276

RESUMO

BACKGROUND: Alzheimer's disease (AD) is characterized by early and region-specific declines in cerebral glucose metabolism. Ketone bodies are produced by the body during glucose deprivation and are metabolized by the brain. An oral ketogenic compound, AC-1202, was tested in subjects with probable AD to examine if ketosis could improve cognitive performance. METHODS: Daily administration of AC-1202 was evaluated in 152 subjects diagnosed with mild to moderate AD in a US-based, 90-day, randomized, double-blind, placebo-controlled, parallel-group study. Subjects were on a normal diet and continued taking approved AD medications. Primary cognitive end points were mean change from Baseline in the AD Assessment Scale-Cognitive subscale (ADAS-Cog), and global scores in the AD Cooperative Study - Clinical Global Impression of Change (ADCS-CGIC). AC-1202 was compared to Placebo in several population groups, including: intention-to-treat (ITT), per protocol, and dosage compliant groups. Results were also stratified by APOE4 carriage status (a predefined analysis based on the epsilon 4 (E4) variant of the apolipoprotein E gene). This trial was registered with ClinicalTrials.gov, registry number NCT00142805, information available at http://clinicaltrials.gov/ct2/show/NCT00142805 RESULTS: AC-1202 significantly elevated a serum ketone body (beta-hydroxybutyrate) 2 hours after administration when compared to Placebo. In each of the population groups, a significant difference was found between AC-1202 and Placebo in mean change from Baseline in ADAS-Cog score on Day 45: 1.9 point difference, p = 0.0235 in ITT; 2.53 point difference, p = 0.0324 in per protocol; 2.6 point difference, p = 0.0215 in dosage compliant. Among participants who did not carry the APOE4 allele (E4(-)), a significant difference was found between AC-1202 and Placebo in mean change from Baseline in ADAS-Cog score on Day 45 and Day 90. In the ITT population, E4(-) participants (N = 55) administered AC-1202 had a significant 4.77 point difference in mean change from Baseline in ADAS-Cog scores at Day 45 (p = 0.0005) and a 3.36 point difference at Day 90 (p = 0.0148) compared to Placebo. In the per protocol population, E4(-) participants receiving AC-1202 (N = 37) differed from placebo by 5.73 points at Day 45 (p = 0.0027) and by 4.39 points at Day 90 (p = 0.0143). In the dosage compliant population, E4(-) participants receiving AC-1202 differed from placebo by 6.26 points at Day 45 (p = 0.0011, N = 38) and 5.33 points at Day 90 (p = 0.0063, N = 35). Furthermore, a significant pharmacologic response was observed between serum beta-hydroxybutyrate levels and change in ADAS-Cog scores in E4(-) subjects at Day 90 (p = 0.008). Adverse events occurred more frequently in AC-1202 subjects, were primarily restricted to the gastrointestinal system, and were mainly mild to moderate in severity and transient in nature. CONCLUSION: AC-1202 rapidly elevated serum ketone bodies in AD patients and resulted in significant differences in ADAS-Cog scores compared to the Placebo. Effects were most notable in APOE4(-) subjects who were dosage compliant.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA