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2.
J Am Med Dir Assoc ; 24(10): 1471-1477, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37419143

RESUMO

OBJECTIVES: Telemedicine and face-to-face outreach services to nursing homes (NHs) have been used to reduce hospital utilization rates for acute presentations. However, how these modalities compare against each other is unclear. This article examines if the management of acute presentations in NHs with care involving telemedicine is noninferior to care delivered face-to-face. DESIGN: A noninferiority study was conducted on a prospective cohort. Face-to-face intervention involved on-site assessment by a geriatrician and aged care clinical nurse specialist (CNS). Telemedicine intervention involved on-site assessment by an aged care CNS with telemedicine input by a geriatrician. SETTING AND PARTICIPANTS: A total of 438 NH residents with acute presentations from 17 NHs between November 2021 and June 2022. METHODS: Between-group differences in proportion of residents successfully managed on-site and mean number of encounters were evaluated using bootstrapped multiple linear regression; 95% CIs were compared against predefined noninferiority margins with noninferiority P values calculated. RESULTS: In the adjusted models, care involving telemedicine demonstrated noninferiority in the difference in proportion of residents successfully managed on-site (95% CI lower limit -6.2% to -1.4% vs -10% noninferiority margin; P < .001 for noninferiority) but not in the difference in mean number of encounters (95% CI upper limit 1.42 to 1.50 encounters vs 1 encounter noninferiority margin; P = .7 for noninferiority). CONCLUSIONS AND IMPLICATIONS: In our model of care, care that involved telemedicine was noninferior to care delivered face-to-face in managing NH residents with acute presentations on-site. However, additional encounters may be required. Application of telemedicine ought to be tailored to fit the needs and preferences of stakeholders.


Assuntos
Telemedicina , Idoso , Humanos , Geriatras , Casas de Saúde , Estudos Prospectivos
3.
PLoS One ; 18(3): e0265285, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36920949

RESUMO

Vascular dementia (VaD) accounts for 15-20% of all dementia cases. It is a syndrome of acquired cognitive impairment with a complex pathophysiological basis. A novel herbal formulation (Sailuotong; SLT) consisting of Panax ginseng C.A Mey, Ginkgo biloba L and Crocus sativus L extracts was developed to treat VaD. Preclinical animal studies found significant improvements in memory and in pathogenic biochemical parameters. Appropriate safety of SLT was shown in acute and chronic toxicity studies, and early clinical trials of SLT demonstrated enhancements in cognition in VaD patients. A fully powered study with a long intervention period is needed to confirm the efficacy and safety of this novel intervention. A rigorous phase III clinical trial was developed with the aim of recruiting 238 patients diagnosed with mild to moderate probable VaD, or VaD mixed with Alzheimer's disease (where cerebrovascular disease is the clinical dominant contributor to dementia, abbreviated as CVD+AD). Using a permuted block strategy, participants will be randomly allocated to receive SLT (120 mg bd) or placebo capsules for an intervention period of 52 weeks and will be followed-up for an additional 13 weeks. The primary outcome measures are the Vascular Dementia Assessment Scale-cognitive subscale and Alzheimer's Disease Cooperative Study-Activities of Daily Living scale. Secondary outcome measures include the Clinician's Interview Based Impression of Change-Plus, CLOX, EXIT-25, Neuropsychiatric Inventory-Clinician rating scale, and Dementia Quality of Life questionnaire. Safety is assessed through adverse event reports and liver, renal, and coagulation studies. Primary and secondary outcome measures will be compared between treatment and placebo groups, using intention to treat and per protocol analyses. We hypothesise that a 52-week treatment of SLT will be clinically effective and well tolerated in participants with VaD or AD+CVD. This project will provide vital efficacy and safety data for this novel treatment approach to VaD.


Assuntos
Doença de Alzheimer , Transtornos Cerebrovasculares , Demência Vascular , Humanos , Animais , Demência Vascular/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/complicações , Atividades Cotidianas , Qualidade de Vida , Transtornos Cerebrovasculares/complicações , Método Duplo-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase III como Assunto
4.
Aging Med (Milton) ; 6(4): 347-352, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38239713

RESUMO

Objectives: It is now recognized that blood brain barrier (BBB) leakage occurs in cerebral small vascular disease (CSVD) and plays a significant role in the pathophysiology of vascular dementia. We hypothesized that genetic polymorphisms of junctional adhesion molecule-A (JAM-A) (which may result in compromised structure of tight junction proteins that form the BBB) in combination with cerebrovascular risk factors hypertension, lipid disorders, and type 2 diabetes may result in BBB leakage and increase the individual's risk of CSVD-related dementia. Methods: In this case-control study, 97 controls with a mean Mini-Mental State Exam (MMSE) score of 29 and 38 CSVD-related vascular dementia participants (mean MMSE score of 19) were recruited. Bloods were collected for the analysis of two common single nucleotide polymorphisms (SNPs) of the JAM-A genotypes rs790056 and rs2481084 using real-time polymerase chain reaction (PCR) assay. Medical history of hypertension, hyperlipidemia, and diabetes was collected for all participants. Results: Polymorphisms of genotype JAM-A SNP rs790056 showed statistically significant result when the subgroup with hyperlipidemia was analyzed (OR = 3.130, p = 0.042 for TC + CC genotypes with hyperlipidaemia vs controls). Similar result was found with diabetes (OR = 4.670, p = 0.031 for TC + CC genotypes vs controls). No significant result was found with hypertension. Borderline results of statistical significance were found for JAM-A SNP rs2481084 with hyperlipidemia (OR = 3.210, p = 0.054 for TC + CC genotypes vs controls) and with diabetes (OR = 3.620, p = 0.069 for TC + CC genotypes vs controls) but not for hypertension. The borderline results might have been due to lack of statistical power because of small sample size. Conclusions: These results lend further support that cerebrovascular risk factors interact with genetic polymorphisms of BBB proteins to increase the risk of vascular dementia.

5.
J Bacteriol ; 204(7): e0013722, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35703565

RESUMO

Members of the AraC family of transcriptional regulators (AFTRs) control the expression of many genes important to cellular processes, including virulence. In Shigella species, the type III secretion system (T3SS), a key determinant for host cell invasion, is regulated by the three-tiered VirF/VirB/MxiE transcriptional cascade. Both VirF and MxiE belong to the AFTRs and are characterized as positive transcriptional regulators. Here, we identify a novel regulatory activity for MxiE and its coregulator IpgC, which manifests as a negative feedback loop in the VirF/VirB/MxiE transcriptional cascade. Our findings show that MxiE and IpgC downregulate the virB promoter and, hence, VirB protein production, thus decreasing VirB-dependent promoter activity at ospD1, one of the nearly 50 VirB-dependent genes. At the virB promoter, regions required for negative MxiE- and IpgC-dependent regulation were mapped and found to be coincident with regions required for positive VirF-dependent regulation. In tandem, negative MxiE- and IpgC-dependent regulation of the virB promoter only occurred in the presence of VirF, suggesting that MxiE and IpgC can function to counter VirF activation of the virB promoter. Lastly, MxiE and IpgC do not downregulate another VirF-activated promoter, icsA, demonstrating that this negative feedback loop targets the virB promoter. Our study provides insight into a mechanism that may reprogram Shigella virulence gene expression following type III secretion and provides the impetus to examine if MxiE and IpgC homologs in other important bacterial pathogens, such as Burkholderia pseudomallei and Salmonella enterica serovars Typhimurium and Typhi, coordinate similar negative feedback loops. IMPORTANCE The large AraC family of transcriptional regulators (AFTRs) control virulence gene expression in many bacterial pathogens. In Shigella species, the AraC/XylS protein MxiE and its coregulator IpgC positively regulate the expression of type III secretion system genes within the three-tiered VirF/VirB/MxiE transcriptional cascade. Our findings suggest a negative feedback loop in the VirF/VirB/MxiE cascade, in which MxiE and IpgC counter VirF-dependent activation of the virB promoter, thus making this the first characterization of negative MxiE- and IpgC-dependent regulation. Our study provides insight into a mechanism that likely reprograms Shigella virulence gene expression following type III secretion, which has implications for other important bacterial pathogens with functional homologs of MxiE and IpgC.


Assuntos
Regulação Bacteriana da Expressão Gênica , Shigella flexneri , Proteínas de Bactérias/metabolismo , Citarabina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Retroalimentação , Shigella flexneri/genética , Shigella flexneri/metabolismo , Transcrição Gênica , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
6.
Cancers (Basel) ; 14(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35565427

RESUMO

Controversy persists regarding metformin's role in cancer therapy. Our recent work suggested metformin acts by impacting the tumor microenvironment (TME), normalizing the epigenetic profile of cancer-associated mesenchymal stem cells (CA-MSC). As CA-MSC can negatively impact tumor immune infiltrates, we evaluated metformin's impact on the human TME, focusing on the interplay of stroma and immune infiltrates. Tumor samples from (i) 38 patients treated with metformin and chemotherapy and (ii) 44 non-metformin matched controls were included in a tissue microarray (TMA). The TMA was used to compare the presence of CA-MSC, desmoplasia and immune infiltrates in the TME. In vitro and in vivo models examined metformin's role in alteration of the CA-MSC phenotype. The average percentage of CA-MSC was significantly lower in metformin-treated than in chemotherapy alone-treated tumors (p = 0.006). There were fewer regulatory T-cells in metformin-treated tumors (p = 0.043). Consistent with CA-MSC's role in excluding T-cells from tumor islets, the T-cells were primarily present within the tumor stroma. Evaluation of metformin's impact in vitro suggested that metformin cannot reverse a CA-MSC phenotype; however, the in vivo model where metformin was introduced prior to the establishment of the CA-MSC phenotype supported that metformin can partially prevent the reprogramming of normal MSC into CA-MSC. Metformin treatment led to a decrease in both the presence of protumorigenic CA-MSC and in immune exclusion of T cells, leading to a more immune-permissive environment. This suggests clinical utility in prevention and in treatment for early-stage disease and putatively in immune therapy.

7.
Comput Struct Biotechnol J ; 18: 1613-1624, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670502

RESUMO

Vascular dementia (VaD) is a complex neurocognitive disorder secondary to a variety of cerebrovascular lesions. Numerous studies have shown that lipid metabolism is involved in the pathobiology of the disease. We examined the plasma lipid profiles in VaD, with the expectation of identifying reliable lipid biomarkers for VaD. 49 VaD patients and 48 healthy controls were recruited from Bankstown-Lidcombe Hospital in Sydney, Australia. Lipids were extracted by single phase 1-butanol/methanol, and untargeted analysis was performed by liquid chromatography coupled-mass spectrometry (LC-MS/MS). Univariate analysis of variance was used to examine the differences in lipid classes and individual lipids between VaD and control groups. In an independent sample of 161 subjects from the Older Australian Twins Study (OATS), elastic net penalization for the generalized linear model (Glmnet) and Random Forest were applied to the lipid levels to subcategorise the sample into vascular cognitive impairment and controls. Most lipids belonging to the classes of ceramides (Cer), cholesterol esters (ChE) and phospholipids were significantly lower in VaD plasma, while glycerides were elevated compared to controls. Levels of ChE, Cer and the two lipid classes together achieved the best accuracy in discriminating VaD from controls, with more than 80% accuracy. The probable VaD group in the OATS sample predicted by the lipid levels showed greater impairment in most cognitive domains, especially attention and processing speed and executive function from controls but did not differ in white matter hyperintensities and DTI measures. As a conclusion, plasma lipids levels, in particular Cer and ChE, are abnormal in VaD and may help discriminate them from healthy controls. Understanding the basis of these differences may provide insights into the pathobiology of VaD.

8.
JCI Insight ; 5(11)2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32369446

RESUMO

BACKGROUNDEpidemiologic studies suggest that metformin has antitumor effects. Laboratory studies indicate metformin impacts cancer stem-like cells (CSCs). As part of a phase II trial, we evaluated the impact of metformin on CSC number and on carcinoma-associated mesenchymal stem cells (CA-MSCs) and clinical outcomes in nondiabetic patients with advanced-stage epithelial ovarian cancer (EOC).METHODSThirty-eight patients with stage IIC (n = 1)/III (n = 25)/IV (n = 12) EOC were treated with either (a) neoadjuvant metformin, debulking surgery, and adjuvant chemotherapy plus metformin or (b) neoadjuvant chemotherapy and metformin, interval debulking surgery, and adjuvant chemotherapy plus metformin. Metformin-treated tumors, compared with historical controls, were evaluated for CSC number and chemotherapy response. Primary endpoints were (a) a 2-fold or greater reduction in aldehyde dehydrogenase-positive (ALDH+) CD133+ CSCs and (b) a relapse-free survival at 18 months of more than 50%.RESULTSMetformin was well tolerated. Median progression-free survival was 18.0 months (95% CI 14.0-21.6) with relapse-free survival at 18 months of 59.3% (95% CI 38.6-70.5). Median overall survival was 57.9 months (95% CI 28.0-not estimable). Tumors treated with metformin had a 2.4-fold decrease in ALDH+CD133+ CSCs and increased sensitivity to cisplatin ex vivo. Furthermore, metformin altered the methylation signature in CA-MSCs, which prevented CA-MSC-driven chemoresistance in vitro.CONCLUSIONTranslational studies confirm an impact of metformin on EOC CSCs and suggest epigenetic change in the tumor stroma may drive the platinum sensitivity ex vivo. Consistent with this, metformin therapy was associated with better-than-expected overall survival, supporting the use of metformin in phase III studies.TRIAL REGISTRATIONClinicalTrials.gov NCT01579812.


Assuntos
Sistemas de Liberação de Medicamentos , Metformina/administração & dosagem , Células-Tronco Neoplásicas , Neoplasias Ovarianas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Metformina/efeitos adversos , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Taxa de Sobrevida
9.
Curr Alzheimer Res ; 17(13): 1167-1176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33583381

RESUMO

BACKGROUND: The interaction between cerebral vessel disease (CVD) pathology and Alzheimer's disease (AD) pathology in the development of dementia is controversial. We examined the association of cerebral vascular neuropathology and cerebrovascular risk factors with the mild stage of Alzheimer's dementia and cognitive function. METHODS: This cross-sectional study included men and women aged 60 years or over who had yearly clinical assessments and had agreed to brain autopsy at the time of death, and who contributed to data stored at the National Alzheimer's Coordinating Center (NACC) in the USA. Cognitively normal and impaired subjects with presumptive aetiology of AD, including mild cognitive impairment (ADMCI) and dementia (Alzheimer's dementia), and with complete neuropathological data, were included in our analyses. We used neuropsychological data proximate to death to create summary measures of global cognition and cognitive domains. Systematic neuropathological assessments documenting the severity of cerebral vascular pathology were included. Logistic and linear regression analyses corrected for age at death, sex and Lewy body pathology were used to examine associations of vessel disease with the severity of Alzheimer's disease dementia, and cognitive function, respectively. RESULTS: No significant relationship was observed between late-life risk factors and Alzheimer's dementia. The severity of arteriosclerosis and presence of global infarcts/lacunes were related to mild Alzheimer's dementia (B=0.423, p<0.001; B=0.366, p=0.026), and the effects were significant after adjusting for neuritic plaques and neurofibrillary tangles (B=0.385, p<0.001; B=0.63, p=0.001). When vascular brain injuries were subdivided into old and acute/subacute types, we found that old microinfarcts and old microbleeds were associated with mild Alzheimer's dementia (B=0.754, p=0.007; B=2.331, p=0.032). The old microinfarcts remained significantly associated with mild Alzheimer's dementia after correcting AD pathologies (B=1.31, p<0.001). In addition, the number of microinfarcts in the cerebral cortex had a significant relation with mild Alzheimer's dementia, whether or not the data were corrected for AD pathologies (B=0.616, p=0.016; B=0.884, p=0.005). Atherosclerosis, arteriosclerosis and white matter rarefaction were found to be significantly associated with faster progression of Alzheimer's dementia (B=0.068, p=0.001; B=0.046, p=0.016, B=0.081, p=0.037), but white matter rarefaction no longer had a significant effect after adjusting for AD pathologies. We also found that the severity of atherosclerosis was related to impairment in processing speed (ß=-0.112, p=0.006) and executive function (ß=-0.092, p=0.023). Arteriosclerosis was significantly associated with language (ß=-0.103, p=0.011) and global cognition (ß=-0.098, p=0.016) deficits. CONCLUSION: Our study found the significant relation of global, old, acute/subacute and regional cerebral vascular pathologies, but not white matter rarefaction, to the onset and severity of Alzheimer's dementia. We also showed that late-life risk factors were found to have no relation with Alzheimer's dementia, and the increased risk of dementia with APOE ε4 is not mediated by CVD. The best interpretation of these findings is that CVD has a potential additive effect with AD pathologies in the development and progression of what is clinically diagnosed as Alzheimer's dementia.


Assuntos
Encéfalo/patologia , Transtornos Cerebrovasculares/patologia , Disfunção Cognitiva/patologia , Bases de Dados Factuais , Neuropatologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Autopsia , Estudos Transversais , Feminino , Humanos , Masculino , Emaranhados Neurofibrilares/patologia , Testes Neuropsicológicos/estatística & dados numéricos , Placa Amiloide/patologia
10.
Front Aging Neurosci ; 11: 177, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440155

RESUMO

Glutathione (GSH) is one of the most abundant thiol antioxidants in cells. Many chronic and age-related diseases are associated with a decline in cellular GSH levels or impairment in the catalytic activity of the GSH biosynthetic enzyme glutamate cysteine ligase (GCL). γ-glutamylcysteine (GGC), a precursor to glutathione (GSH), can replenish depleted GSH levels under oxidative stress conditions, by circumventing the regulation of GSH biosynthesis and providing the limiting substrate. Soluble amyloid-ß (Aß) oligomers have been shown to induce oxidative stress, synaptic dysfunction and memory deficits which have been reported in Alzheimer's disease (AD). Calcium ions, which are increased with age and in AD, have been previously reported to enhance the formation of Aß40 oligomers, which have been casually associated with the pathogenesis of the underlying neurodegenerative condition. In this study, we examined the potential beneficial effects of GGC against exogenous Aß40 oligomers on biomarkers of apoptosis and cell death, oxidative stress, and neuroinflammation, in human astrocytes. Treatment with Aß40 oligomers significantly reduced the cell viability and apoptosis of astrocyte brain cultures and increased oxidative modifications of DNA, lipids, and protein, enhanced pro-inflammatory cytokine release and increased the activity of the proteolytic matrix metalloproteinase enzyme, matric metalloproteinase (MMP)-2 and reduced the activity of MMP-9 after 24 h. Co-treatment of Aß40 oligomers with GGC at 200 µM increased the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) and led to significant increases in the levels of the total antioxidant capacity (TAC) and GSH and reduced the GSSG/GSH ratio. GGC also upregulated the level of the anti-inflammatory cytokine IL-10 and reduced the levels of the pro-inflammatory cytokines (TNF-α, IL-6, and IL-1ß) and attenuated the changes in metalloproteinase activity in oligomeric Aß40-treated astrocytes. Our data provides renewed insight on the beneficial effects of increased GSH levels by GGC in human astrocytes, and identifies yet another potential therapeutic strategy to attenuate the cytotoxic effects of Aß oligomers in AD.

11.
Intern Med J ; 48(11): 1396-1399, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30387300

RESUMO

To share our experience of establishing an acute outreach service to nursing homes and to evaluate the impact of such service on emergency department presentations, data were drawn from a pre-existing database from 2013 to 2017. Of the 986 acute patients treated in 12 nursing homes over a 23-month period, the acute geriatric outreach service was shown to be safe, with few adverse events (one allergic reaction) and 5.3% of patients required transfer to hospital. The acute service decreased emergency department presentation of nursing home patients by 10% compared to the subacute service (incidence rate ratio = 0.90; 95% confidence interval: 0.84-0.96; P = 0.001). Cost-benefit analysis showed for every $1 spent, a saving of $5 was realised.


Assuntos
Serviço Hospitalar de Emergência/organização & administração , Instituição de Longa Permanência para Idosos/organização & administração , Casas de Saúde/organização & administração , Transferência de Pacientes/organização & administração , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Austrália , Análise Custo-Benefício/economia , Serviço Hospitalar de Emergência/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Instituição de Longa Permanência para Idosos/economia , Humanos , Masculino , Casas de Saúde/economia , Transferência de Pacientes/economia , Transferência de Pacientes/estatística & dados numéricos
12.
Ageing Res Rev ; 47: 41-48, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29898422

RESUMO

BACKGROUND: Cerebral small vessel disease (CSVD) comprises a variety of disorders affecting small arteries and microvessels of the brain, manifesting as white matter hyperintensities (WMHs), cerebral microbleeds (CMBs), and deep brain infarcts. In addition to its contribution to vascular dementia (VaD), it has also been suggested to contribute to the pathogenesis of Alzheimer's disease (AD). METHOD: A systematic review of the literature available on Medline, Embase and Pubmed was undertaken, whereby CSVD was divided into WMHs, CMBs and deep brain infarcts. Biomarkers of AD pathology in the cerebrospinal fluid or plasma, or positron emission tomographic imaging for amyloid and/or tau deposition were used for AD pathology. RESULTS: A total of 4117 articles were identified and 41 articles met criteria for inclusion. These consisted of 17 articles on vascular risk factors for clinical AD, 21 articles on Aß pathology and 15 articles on tau pathology, permitting ten meta-analyses. CMBs or lobar CMBs were associated with pooled relative risk (RR) of AD at 1.546, (95%CI 0.842-2.838, z = 1.41 p = 0.160) and 1.526(95%CI 0.760-3.063, z = 1.19, p = 0.235) respectively, both non-significant. Microinfarcts were associated with significantly increased AD risk, with pooled odds ratio OR at 1.203(95%CI 1.014-1.428, 2.12 p = 0.034). Aß pathology was significantly associated with WMHs in AD patients but not in normal age-matched controls. The pooled ß (linear regression) for total WMHs with CSF Aß42 in AD patients was -0.19(95%CI -0.26-0.11, z = 4.83 p = 0.000) and the pooled r (correlation coefficient) for WMHs and PiB in the normal population was -0.10 (95%CI -0.11-0.30, 0.93 p = 0.351). CMBs were significantly associated with Aß pathology in AD patients. The pooled standardized mean difference (SMD) was -0.453, 95%CI -0.697- -0.208, z = 3.63 p = 0.000. There was no significant relationship between the incidence of lacunes and levels of CSFAß, with a pooled ß of 0.057 (95%CI -0.050-0.163, z = 1.05 p = 0.295). No significant relationship was found between CMBs and the levels of CSFt-tau/CSFp-tau in AD patients (-0.014, 95%CI -0.556-0.529, z = 0.05 p = 0.960; -0.058, 95%CI -0.630-0.515, z = 0.20 p = 0.844) and cortical CMBs and CSF p-tau in the normal population (0.000, 95%CI -0.706-0.706, z = 0.00 p = 0.999). CONCLUSIONS: Some CSVD markers were significantly associated with clinical AD pathology and may be associated with Aß/tau pathology. WMHs and microinfarcts were associated with increased risk of AD. It remains unclear whether they precede or follow AD pathology.


Assuntos
Doença de Alzheimer/epidemiologia , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Doenças de Pequenos Vasos Cerebrais/epidemiologia , Doenças de Pequenos Vasos Cerebrais/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/metabolismo , Biomarcadores/metabolismo , Encéfalo/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Estudos Transversais , Demência Vascular/diagnóstico por imagem , Demência Vascular/epidemiologia , Demência Vascular/metabolismo , Humanos , Estudos Longitudinais , Tomografia por Emissão de Pósitrons/métodos , Proteínas tau/metabolismo
13.
Aging Med (Milton) ; 1(1): 50-54, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31942480

RESUMO

The Australian aged care service is a mature and evolving service. It is comprehensive with good continuity of care between hospital and community. Innovative models of care that are built on the principles of improved efficiency, better quality, and safety are constantly being introduced as our population is aging, resulting in higher demand in our healthcare services and increasing healthcare cost. Collaborative effort of a multidisciplinary team underpins our successful aged care model as most of our older patients have multiple comorbidities with various functional and psychosocial needs. General practitioners play an important role in the care of older patients in the community.

15.
Neurotox Res ; 30(3): 479-85, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27364697

RESUMO

Increasing evidence suggests an important role of alpha-synuclein (α-Syn) in the pathogenesis of Parkinson's disease (PD). The inter-neuronal spread of α-Syn via exocytosis and endocytosis has been proposed as an explanation for the neuropathological findings of PD in sub-clinical and clinical phases. Therefore, interfering the uptake of α-Syn by neurons may be an important step in slowing or modifying the propagation of the disease. The purposes of our study were to investigate if the uptake of α-Syn fibrils can be specifically interfered with monomeric ß-Amyloid1-40 (Aß40) and to characterise the core acting site of interference. Using a radioisotope-labelled uptake assay, we found an 80 % uptake reduction of α-Syn fibrils in neurons interfered with monomeric Aß40, but not ß-Amyloid1-42 (Aß42) as compared to controls. This finding was further confirmed by enzyme-linked immunosorbent assay (ELISA) with α-Syn uptake reduced from about 80 % (Aß42) to about 20 % (Aß40) relative to controls. To define the region of Aß40 peptide capable of the interference, we explored shorter peptides with less amino acid residues from both the C-terminus and N-terminus. We found that the interference effect was preserved if amino acid residue was trimmed to position 11 (from N-terminus) and 36 (from C-terminus), but dropped off significantly if residues were trimmed beyond these positions. We therefore deduced that the "core acting site" lies between amino acid residue positions 12-36. These findings suggest α-Syn uptake can be interfered with monomeric Aß40 and that the core acting site of interference might lie between amino acid residue positions 12-36.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Endocitose/fisiologia , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , alfa-Sinucleína/metabolismo , Sequência de Aminoácidos , Peptídeos beta-Amiloides/genética , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Humanos , Hidrazonas/metabolismo , Imunoquímica , Microscopia de Fluorescência , Neurônios/patologia , Fragmentos de Peptídeos/genética , Proteínas Recombinantes/metabolismo , Sertralina/metabolismo , Proteínas tau/metabolismo
16.
Clin Exp Pharmacol Physiol ; 43(5): 515-21, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26859837

RESUMO

Vascular dementia (VaD) describes a combination of both cognitive and behavioural manifestations associated with variable brain lesions of vascular origin. While vascular risk factors have been implicated in VaD, the relationship is most evident when the factors are considered together and not individually. This review will examine the significance of the integrity of blood brain barrier (BBB) tight junction (TJ) proteins - occludin and claudins in the pathophysiology of VaD. Specifically, some of the genetic contributors to VaD, namely those responsible for the integrity of the BBB, will be reviewed in detail. Moreover, environmental factors will be considered in conjunction with these genes to examine how the interaction of environmental and genetic factors contributes to one's susceptibility to VaD.


Assuntos
Barreira Hematoencefálica/metabolismo , Demência Vascular/genética , Meio Ambiente , Demência Vascular/metabolismo , Demência Vascular/fisiopatologia , Interação Gene-Ambiente , Humanos , Fatores de Risco
17.
World J Gastroenterol ; 22(4): 1639-49, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26819529

RESUMO

Volatile organic compounds (VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundance of hydrogen, carbon dioxide, and methane that have already been identified in human flatus, the small portion of trace gases making up the VOCs emitted from stool include organic acids, alcohols, esters, heterocyclic compounds, aldehydes, ketones, and alkanes, among others. These are the gases that vary among individuals in sickness and in health, in dietary changes, and in gut microbial activity. Electronic nose devices are analytical and pattern recognition platforms that can utilize mass spectrometry or electrochemical sensors to detect these VOCs in gas samples. When paired with machine-learning and pattern recognition algorithms, this can identify patterns of VOCs, and thus patterns of smell, that can be used to identify disease states. In this review, we provide a clinical background of VOC identification, electronic nose development, and review gastroenterology applications toward diagnosing disease by the volatile headspace analysis of stool.


Assuntos
Técnicas Biossensoriais/instrumentação , Nariz Eletrônico , Fezes/química , Gastroenteropatias/diagnóstico , Odorantes , Compostos Orgânicos Voláteis/análise , Algoritmos , Biomarcadores/análise , Técnicas Eletroquímicas , Gastroenteropatias/metabolismo , Humanos , Aprendizado de Máquina , Espectrometria de Massas , Reconhecimento Automatizado de Padrão , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
18.
Gastrointest Endosc ; 83(5): 880-888.e2, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26344884

RESUMO

BACKGROUND AND AIMS: Probe-based confocal laser endomicroscopy (pCLE) and volumetric laser endomicroscopy (VLE) (also known as frequency domain optical coherence tomography) are advanced endoscopic imaging modalities that may be useful in the diagnosis of dysplasia associated with Barrett's esophagus (BE). We performed pCLE examination in ex-vivo EMR specimens and compared the diagnostic performance of using the current VLE scoring index (previously established as OCT-SI) and a novel VLE diagnostic algorithm (VLE-DA) for the detection of dysplasia. METHODS: A total of 27 patients with BE enrolled in a surveillance program at a tertiary-care center underwent 50 clinically indicated EMRs that were imaged with VLE and pCLE and classified into neoplastic (N = 34; high-grade dysplasia, intramucosal adenocarcinoma) and nonneoplastic (N = 16; low-grade dysplasia, nondysplastic BE), based on histology. Image datasets (VLE, N = 50; pCLE, N = 50) were rated by 3 gastroenterologists trained in the established diagnostic criteria for each imaging modality as well as a new diagnostic algorithm for VLE derived from a training set that demonstrated association of specific VLE features with neoplasia. Sensitivity, specificity, and diagnostic accuracy were assessed for each imaging modality and diagnostic criteria. RESULTS: The sensitivity, specificity, and diagnostic accuracy of pCLE for detection of BE dysplasia was 76% (95% confidence interval [CI], 59-88), 79% (95% CI, 53-92), and 77% (95% CI, 72-82), respectively. The optimal diagnostic performance of OCT-SI showed a sensitivity of 70% (95% CI, 52-84), specificity of 60% (95% CI, 36-79), and diagnostic accuracy of 67%; (95% CI, 58-78). The use of the novel VLE-DA showed a sensitivity of 86% (95% CI, 69-96), specificity of 88% (95% CI, 60-99), and diagnostic accuracy of 87% (95% CI, 86-88). The diagnostic accuracy of using the new VLE-DA criteria was significantly superior to the current OCT-SI (P < .01). CONCLUSION: The use of a new VLE-DA showed enhanced diagnostic performance for detecting BE dysplasia ex vivo compared with the current OCT-SI. Further validation of this algorithm in vivo is warranted.


Assuntos
Esôfago de Barrett/diagnóstico por imagem , Esôfago de Barrett/patologia , Microscopia Confocal/métodos , Tomografia de Coerência Óptica , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Esôfago de Barrett/cirurgia , Ressecção Endoscópica de Mucosa , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Female Pelvic Med Reconstr Surg ; 21(3): e27-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25730427

RESUMO

BACKGROUND: Dyssynergic defecation is a complex bowel problem that leads to chronic constipation and abdominal pain. Management is often challenging owing to the incoordination of multiple pelvic floor muscles involved in normal defecation. CASE: We report a case of dyssynergic defecatory dysfunction in a patient with cerebral palsy treated with sacral neuromodulation. At presentation, Sitz marker study and magnetic resonance defecography showed evidence of chronic functional constipation. Anorectal manometry, rectal anal inhibitory reflex, and rectal sensation study showed intact reflex and decreased first sensation of lower canal at 50 mL. After stage 2 of InterStim implant placement, bowel habits improved to once- to twice-daily soft solid bowel movements from no regular solid bowel movements. Fecal incontinence improved from daily liquid and small solid loss to no stool leakage. CONCLUSIONS: In patients with systemic medical problems contributing to defecatory dysfunction and bowel incontinence, such as cerebral palsy, sacral neuromodulation was found to provide significant relief of bowel symptoms in addition to associated abdominal pain. As a result of intervention, the patient reported significant improvement in quality of life and less limitations due to dyssynergic defecation.


Assuntos
Paralisia Cerebral/complicações , Constipação Intestinal/terapia , Terapia por Estimulação Elétrica/métodos , Dor Abdominal/etiologia , Constipação Intestinal/complicações , Constipação Intestinal/fisiopatologia , Defecografia , Terapia por Estimulação Elétrica/instrumentação , Feminino , Motilidade Gastrointestinal/fisiologia , Humanos , Neuroestimuladores Implantáveis , Manometria , Doenças Retais/fisiopatologia , Reflexo/fisiologia , Adulto Jovem
20.
Hong Kong Med J ; 21(2): 165-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25722468

RESUMO

Falls are a common problem in the elderly. A common error in their management is that injury from the fall is treated, without finding its cause. Thus a proactive approach is important to screen for the likelihood of fall in the elderly. Fall assessment usually includes a focused history and a targeted examination. Timed up-and-go test can be performed quickly and is able to predict the likelihood of fall. Evidence-based fall prevention interventions include multi-component group or home-based exercises, participation in Tai Chi, environmental modifications, medication review, management of foot and footwear problems, vitamin D supplementation, and management of cardiovascular problems. If possible, these are best implemented in the form of multifactorial intervention. Bone health enhancement for residential care home residents and appropriate community patients, and prescription of hip protectors for residential care home residents are also recommended. Multifactorial intervention may also be useful in a hospital and residential care home setting. Use of physical restraints is not recommended for fall prevention.


Assuntos
Acidentes por Quedas/prevenção & controle , Envelhecimento/fisiologia , Exercício Físico/fisiologia , Prevenção Primária/organização & administração , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Meio Ambiente , Medicina Baseada em Evidências , Feminino , Avaliação Geriátrica/métodos , Hong Kong/epidemiologia , Humanos , Estilo de Vida , Masculino , Equilíbrio Postural/fisiologia , Prognóstico , Medição de Risco , Transtornos de Sensação/epidemiologia , Transtornos de Sensação/prevenção & controle , Pesquisa Translacional Biomédica , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/prevenção & controle
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