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1.
Artigo em Inglês | MEDLINE | ID: mdl-38849235

RESUMO

AIMS: WHO Grade 3 (G3) meningiomas are rare tumours with limited data to guide management. This retrospective study documents UK management approaches across 14 centres over 11 years. MATERIALS AND METHODS: Patients with WHO G3 meningioma between 01/01/2008 and 31/12/2018 were identified. Data were collected on demographics, management strategy, adjuvant radiotherapy, approach in recurrence setting and survival. RESULTS: 84 patients were identified. 21.4% transformed from lower-grade disease. 96.4% underwent primary surgical resection, with 20.8% having evidence of residual disease on their post-op MRI. 59.3% of patients underwent adjuvant radiotherapy (RT) following surgical resection. Overall median PFS and OS were 12.6 months and 28.2 months, respectively. Median OS in the group who underwent complete surgical resection was 34.9 months, compared to 27.5 months for those who had incomplete resection (HR 0.58, 95% CI 0.27-1.23, p = 0.15). Median OS was 33.1 months for those who underwent adjuvant RT and 14.0 months for those who did not (HR 0.48, 95% CI 0.27-0.84, p = 0.004). Median adjuvant RT dose delivered was 60Gy (range 12Gy-60Gy), 45.8% of adjuvant RT was delivered using IMRT. At disease relapse, 31% underwent salvage surgery and 29.3% underwent salvage RT. Of those treated with salvage RT, 64.7% were re-treats and all were treated with hypofractionated RT. CONCLUSION: Surgery continues to be the preferred primary management strategy. Post-operative MRI within 48 hours is indicated to assess presence of residual disease and guide further surgical options. Adjuvant radiotherapy plays an important part of the management paradigm in these patients with the data supporting an attached survival advantage. Further surgery and re-irradiation is an option in the disease recurrence setting with radiosurgery frequently utilised in this context.

2.
Mymensingh Med J ; 33(1): 294-297, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163806

RESUMO

Vulval cancer is a rare gynaecological malignancy. Though it has got excellent prognosis if diagnosed and treated early, but in most instances, women present late with advanced disease as they are too uncomfortable to discuss it with their doctors. Advanced vulval cancer is difficult to treat, has got poor prognosis and the treatment itself can cause morbidity and mortality. The authors describe three cases of isolated vulval cancer in a gynaecology centre in south Wales that had late presentation due to embarrassment despite noticing the lesion for long time and a brief review of the literature on its prevalence, clinical presentation, investigation and best management.


Assuntos
Ginecologia , Neoplasias Vulvares , Feminino , Humanos , Neoplasias Vulvares/diagnóstico , Neoplasias Vulvares/terapia , Prognóstico
3.
J Neonatal Perinatal Med ; 16(4): 701-708, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38073400

RESUMO

BACKGROUND: Neonatal hypothermia is a drop in the newborn's core temperature less than 36.5°C. It is crucial in neonatal morbidity and mortality, particularly in preterm infants. This research aimed to assess the incidence and risk factors of neonatal hypothermia and its effect on neonatal mortality and short-term morbidity during Neonatal Intensive Care Unit (NICU) admission. METHODS: This observational study was conducted on all neonates admitted to the NICU at Benha University Hospital. The core temperature was measured on admission for all admitted neonates and were followed up to assess the impact of hypothermia on short-term outcomes and mortality. RESULTS: A total of 323 neonates were admitted to the NICU throughout the research period. Thirty-five cases were excluded due to congenital anomalies or missing or late admission temperature recordings. The study included 288 neonates whose mean gestational age was 34.6±3.4 weeks, and their mean birth weight was 2.35±0.9 kg. Two-thirds (66%) of the neonates had core temperatures indicating hypothermia (axillary temperature of less than 36.5°C), one-third (33%) were normothermic, and only three (1%) were hyperthermic. Neonates with hypothermia had statistically lower gestational age, higher frequency of multiple births, prolonged need for respiratory support, higher rates of pulmonary hemorrhage, sepsis, intraventricular hemorrhage (IVH), and necrotizing enterocolitis, longer hospital stay, and mortality. CONCLUSIONS: There is a high incidence of neonatal hypothermia at NICU admission. Lower gestational age, increased multiples, lower APGAR score, lower birth weight, and lack of antenatal steroids were significantly associated with hypothermia at NICU admission. Hypothermia was found to be a significant factor contributing to increased mortality and morbidity rates in affected neonates.


Assuntos
Hipotermia , Recém-Nascido Prematuro , Humanos , Recém-Nascido , Peso ao Nascer , Hemorragia , Hipotermia/epidemiologia , Mortalidade Infantil , Unidades de Terapia Intensiva Neonatal , Morbidade
4.
PLoS One ; 18(10): e0293201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37874849

RESUMO

BACKGROUND: Malaria continues to pose a major public health challenge in tropical regions. Despite significant efforts to control malaria in Tanzania, there are still residual transmission cases. Unfortunately, little is known about where these residual malaria transmission cases occur and how they spread. In Tanzania for example, the transmission is heterogeneously distributed. In order to effectively control and prevent the spread of malaria, it is essential to understand the spatial distribution and transmission patterns of the disease. This study seeks to predict areas that are at high risk of malaria transmission so that intervention measures can be developed to accelerate malaria elimination efforts. METHODS: This study employs a geospatial based model to predict and map out malaria risk area in Kilombero Valley. Environmental factors related to malaria transmission were considered and assigned valuable weights in the Analytic Hierarchy Process (AHP), an online system using a pairwise comparison technique. The malaria hazard map was generated by a weighted overlay of the altitude, slope, curvature, aspect, rainfall distribution, and distance to streams in Geographic Information Systems (GIS). Finally, the risk map was created by overlaying components of malaria risk including hazards, elements at risk, and vulnerability. RESULTS: The study demonstrates that the majority of the study area falls under moderate risk level (61%), followed by the low risk level (31%), while the high malaria risk area covers a small area, which occupies only 8% of the total area. CONCLUSION: The findings of this study are crucial for developing spatially targeted interventions against malaria transmission in residual transmission settings. Predicted areas prone to malaria risk provide information that will inform decision-makers and policymakers for proper planning, monitoring, and deployment of interventions.


Assuntos
Malária , Humanos , Tanzânia/epidemiologia , Malária/epidemiologia , Malária/prevenção & controle , Meio Ambiente , Sistemas de Informação Geográfica , Saúde Pública
5.
Med J Malaysia ; 78(5): 675-686, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37775497

RESUMO

INTRODUCTION: Postpartum depression (PPD) is a mental and emotional condition that can affect women during their first postnatal year and concern globally. This study aimed to determine the overall prevalence and determinants of postpartum depression (PPD) in Association of Southeast Asian Nations (ASEAN) countries. MATERIALS AND METHODS: A systematic search of observational studies conducted in ASEAN countries between 1 January 2010 and 31 December 2020 was performed in the Medline, PubMed and Google Scholar databases. The quality of studies was evaluated based on The Joanna Briggs Institute Checklist. The analysis was performed with Review Manager software version 5.4. Metaanalysis of the estimates from primary studies was conducted by adjusting for possible publication bias and heterogeneity. RESULTS: Twenty-five studies including 19924 postnatal mothers were included in this review. The pooled prevalence of PPD is 22.32% (95% CI: 18.48, 26.17). Thailand has the highest prevalence of PPD with a pooled prevalence of 74.1% (95% CI: 64.79, 83.41). The prevalence of PPD was highest when the assessment for PPD was conducted up to 6 weeks postpartum with a pooled prevalence of 25.24% (95% CI: 14.08, 36.41). The identified determinants of PPD were unplanned pregnancy, term pregnancy, lack of family support and physical violence. There were limited studies done and high heterogeneity in terms of quality, methodology, culture, screening method and time of PPD measurement. CONCLUSIONS: Approximately one in five postpartum women in ASEAN countries had PPD. The risk factor that lowers the risk of PPD is unplanned and term pregnancies, while women with a lack of family support and experienced physical violence increase the risk of PPD. Robust prevalence studies are needed to assess the magnitude of this problem in ASEAN countries.


Assuntos
Depressão Pós-Parto , Gravidez , Feminino , Humanos , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/psicologia , População do Sudeste Asiático , Mães , Período Pós-Parto , Fatores de Risco , Prevalência
6.
Mymensingh Med J ; 32(3): 841-846, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37391983

RESUMO

Evaluation of our practice and recommend an appropriate fluid regime to maintain the fluid and electrolyte balance in the post operative period. The drug chart and clinical notes were retrospectively analysed manually of 758 patients who underwent surgery from January 2020 to January 2022 in Enam Medical College Hospital and Ibnsina Medical College Hospital, Dhaka, Bangladesh were reviewed by 3 individual clinicians and the obtained data were analysed. Total 407 patients met the inclusion criteria for the study. Fifty seven (57) patients underwent emergency operation and 350 patients had elective surgery. The average fluid replacement was 2.5 L/day, average Sodium- 154 mmol/day, average potassium 2.0 mmol/day and average glucose 125 mmol/day. Post operatively 97 patients developed hypokalemia. Among them 25 patients developed severe hypokalemia. A simple pathway for prescribing post operative fluid and electrolyte was proposed so that patients during 1st post operative day requiring maintenance fluid will have 25-30 ml/kg/day of water, approximately 1-2 mmol/kg/day Sodium and chloride, 1 mmol/kg/day of potassium and approximately 50-100 gm/day of glucose.


Assuntos
Hipopotassemia , Humanos , Estudos Retrospectivos , Bangladesh , Hipopotassemia/etiologia , Hipopotassemia/terapia , Eletrólitos , Potássio , Glucose , Sódio
7.
Mymensingh Med J ; 32(1): 247-250, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36594328

RESUMO

The most common presentation of the most common gynaecological malignancy (Endometrial Cancer) is abnormal PV bleeding. Transvaginal sonography (TVS) is the first line investigation to assess the endometrial nature. Four to five (4-5) millimetre endometrial thicknesses is considered as the normal cut off in post menopausal women. But endometrial cancer can be present while endometrial thickness is less than 4mm. The author describes three cases of isolated endometrial cancer in Glangwili General Hospital in Wales, UK that was diagnosed despite endometrial thickness being less than 4mm and a brief review of the literature on its prevalence, risk factors, clinical presentation, diagnosis and therapeutic approach.


Assuntos
Neoplasias do Endométrio , Hemorragia Uterina , Feminino , Humanos , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/patologia , Ultrassonografia , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/terapia , Neoplasias do Endométrio/patologia , Endométrio/diagnóstico por imagem , Endométrio/patologia
8.
RSC Adv ; 12(44): 28364-28375, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36320495

RESUMO

We present the effective synthesis and structural characterization of three novel imidazolium-thiohydantoin ligands (IMTHs, 5a-c) and their Mn(iii) complexes (Mn(iii)IMTHs, 6a-c) in this study. The findings of elemental analyses, spectral analyses and magnetic measurements will be used to infer the stoichiometry, coordination styles, and geometrical aspects of Mn(iii)IMTHs. The new compounds were evaluated for their chemotherapeutic potential against ESKAPE pathogens and liver cancer (HepG2). According to the MIC and MBC values, the bactericidal and bacteriostatic activities of IMTHs have been significantly improved following coordination with the Mn(iii) ion. The MTT assay results showed that all Mn(iii)IMTHs had the potential to reduce the viability of liver carcinoma (HepG2) cells in a dose-dependent manner, with the BF4-supported complex (6b) outperforming its counterparts (6a and 6c) as well as a clinical anticancer drug (VBL). Additionally, Mn-IMTH2 (6b) showed the highest level of selectivity (SI = 32.05) for targeting malignant cells (HepG2) over healthy cells (HL7702).

9.
ESMO Open ; 7(6): 100636, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36423363

RESUMO

BACKGROUND: Immune checkpoint inhibition is an established treatment in programmed death-ligand 1 (PD-L1)-positive metastatic triple-negative (TN) breast cancer (BC). However, the immune landscape of breast cancer brain metastasis (BCBM) remains poorly defined. MATERIALS AND METHODS: The tumour-infiltrating lymphocytes (TILs) and the messenger RNA (mRNA) levels of 770 immune-related genes (NanoString™, nCounter™ Immuno-oncology IO360) were assessed in primary BCs and BCBMs. The prognostic role of ARG2 transcripts and protein expression in primary BCs and its association with outcome was determined. RESULTS: There was a significant reduction of TILs in the BCBMs in comparison to primary BCs. 11.5% of BCs presented a high immune infiltrate (hot), 46.2% were altered (immunosuppressed/excluded) and 34.6% were cold (no/low immune infiltrate). 3.8% of BCBMs were hot, 23.1% altered and 73.1% cold. One hundred and twelve immune-related genes including PD-L1 and CTLA4 were decreased in BCBM compared to the primary BCs (false discovery rate <0.01, log2 fold-change >1.5). These genes are involved in matrix remodelling and metastasis, cytokine-chemokine signalling, lymphoid compartment, antigen presentation and immune cell adhesion and migration. Immuno-modulators such as PD-L1 (CD274), CTLA4, TIGIT and CD276 (B7H3) were decreased in BCBMs. However, PD-L1 and CTLA4 expression was significantly higher in TN BCBMs (P = 0.01), with CTLA4 expression also high in human epidermal growth factor receptor 2-positive (P < 0.01) compared to estrogen receptor-positive BCBMs. ARG2 was one of four genes up-regulated in BCBMs. High ARG2 mRNA expression in primary BCs was associated with worse distant metastasis-free survival (P = 0.038), while ARG2 protein expression was associated with worse breast-brain metastasis-free (P = 0.027) and overall survival (P = 0.019). High transcript levels of ARG2 correlated to low levels of cytotoxic and T cells in both BC and BCBM (P < 0.01). CONCLUSION: This study highlights the immunological differences between primary BCs and BCBMs and the potential importance of ARG2 expression in T-cell depletion and clinical outcome.


Assuntos
Arginase , Neoplasias Encefálicas , Neoplasias da Mama , Linfócitos T , Microambiente Tumoral , Feminino , Humanos , Antígenos B7/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Antígeno CTLA-4/genética , Arginase/genética , Arginase/metabolismo , Neoplasias Encefálicas/secundário
10.
Mymensingh Med J ; 31(3): 848-850, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35780373

RESUMO

To develop an efficient and practical pathway to reduce the waiting list for outpatient hysteroscopy in patients with post menopausal bleeding. The clinical data was retrospectively analysed in Welsh Clinical Portal of 1339 patients who were referred for hysteroscopy as urgent suspected cancer over a period of 12 months (1st January to 31st December 2019) in Hywel DDA University Health Board in Wales, United Kingdom. A total of 1339 patients were referred for hysteroscopy over 12 months. Among them 133 patients underwent hysteroscopy for evaluation of PMB despite ET being less than 4 mm; 1.50% patients were on tamoxifen and 16.45% were on HRT. Biopsy was taken for 86.00% of patients. Among them 1.50% were reported as malignant, 72.00% benign and 9.80% as insufficient sample. Patients with PMB and ET less than 4 mm and without suspicious features on ultrasound and who are without clinical risk factors can be reviewed virtually (in virtual clinics) by consultants or senior doctor and can be discharged. They should be instructed to report back if they experience persistent bleeding and then they would need hysteroscopy for further evaluation.


Assuntos
COVID-19 , Histeroscopia , Feminino , Humanos , Pandemias , Pós-Menopausa , Gravidez , Estudos Retrospectivos , Listas de Espera
11.
Ann R Coll Surg Engl ; 103(3): e101-e105, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33645269

RESUMO

Suprarenal or adrenal gland haemorrhage is an uncommon but potentially lethal condition if unrecognised. Adrenal masses rarely present with haemorrhage, but they remain an important differential aetiology for adrenal bleeding. We present a novel case of primary adrenal lymphoma with adrenal haemorrhage in a middle-aged woman who presented with right-sided abdominal pain and class 1 haemorrhagic shock. She was found to have spontaneous unilateral adrenal gland haemorrhage in the absence of any underlying previous pathology. Presenting features, diagnosis and subsequent oncological management are reported.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Linfadenopatia/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Choque Hemorrágico/diagnóstico , Dor Abdominal/etiologia , Doenças das Glândulas Suprarrenais/diagnóstico por imagem , Doenças das Glândulas Suprarrenais/etiologia , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Neoplasias das Glândulas Suprarrenais/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Feminino , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Humanos , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Rituximab/uso terapêutico , Choque Hemorrágico/etiologia , Tomografia Computadorizada por Raios X , Ultrassonografia , Vincristina/uso terapêutico
12.
Cancer Radiother ; 25(1): 62-71, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33414057

RESUMO

PURPOSE: Nasopharyngeal carcinoma (NPC) radiotherapy (RT) irradiates parts of the brain which may cause cerebral tissue changes. This study aimed to systematically review the brain microstructure changes using MRI-based measures, diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI) and voxel-based morphometry (VBM) and the impact of dose and latency following RT. METHODS: PubMed and Scopus databases were searched based on PRISMA guideline to determine studies focusing on changes following NPC RT. RESULTS: Eleven studies fulfilled the inclusion criteria. Microstructural changes occur most consistently in the temporal region. The changes were correlated with latency in seven studies; fractional anisotropy (FA) and gray matter (GM) volume remained low even after a longer period following RT and areas beyond irradiation site with reduced FA and GM measures. For dosage, only one study showed correlation, thus requiring further investigations. CONCLUSION: DTI, DKI and VBM may be used as a surveillance tool in detecting brain microstructural changes of NPC patients which correlates to latency and brain areas following RT.


Assuntos
Encéfalo/efeitos da radiação , Imageamento por Ressonância Magnética , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Encéfalo/diagnóstico por imagem , Encéfalo/ultraestrutura , Imagem de Tensor de Difusão , Humanos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/efeitos da radiação , Lobo Temporal/ultraestrutura
13.
Arch Pediatr ; 26(1): 30-33, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30554849

RESUMO

PURPOSE: The aim of the study was to determine the age at menarche of Moroccan girls by place of residence (rural vs. urban). METHODS: The data were derived from a survey conducted between 2014 and 2016 in schools of the Marrakesh region. A total of 433 questionnaires were completed by 433 girls aged 9-18 years, with 245 (56.6%) living in urban areas and 188 (43.4%) in rural areas. The mean and median age at menarche of the girls were estimated by retrospective and status-quo methods, respectively. The sociodemographic variables used were the parents' educational level, the parents' socioeconomic status, and family size. RESULTS: Out of the 433 girls surveyed, 265 had attained menarche, and the mean was at 13.10 years. The median age at menarche was 13.46 years. According to the place of residence, the girls living in urban areas on average had their first menstruation earlier than girls from rural areas. The mean and median ages at menarche of urban girls were 12.96 years and 13.16 years, respectively, compared with 13.34 years and 13.94 years for their rural counterparts. CONCLUSION: What can be inferred from this study is that the place of residence is a differential factor of age at menarche. This can be related to differences in the living conditions between the two environments.


Assuntos
Fatores Etários , Menarca , Características de Residência/estatística & dados numéricos , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Criança , Feminino , Humanos , Marrocos , Estudos Retrospectivos , Classe Social , Inquéritos e Questionários
14.
Physiol Res ; 66(4): 553-565, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28406691

RESUMO

Alzheimer's disease (AD) is a primary cause of dementia in the middle-aged and elderly worldwide. Animal models for AD are widely used to study the disease mechanisms as well as to test potential therapeutic agents for disease modification. Among the non-genetically manipulated neuroinflammation models for AD, lipopolysaccharide (LPS)-induced animal model is commonly used. This review paper aims to discuss the possible factors that influence rats' response following LPS injection. Factors such as dose of LPS, route of administration, nature and duration of exposure as well as age and gender of animal used should be taken into account when designing a study using LPS-induced memory impairment as model for AD.


Assuntos
Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/metabolismo , Modelos Animais de Doenças , Lipopolissacarídeos/toxicidade , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/metabolismo , Doença de Alzheimer/patologia , Animais , Humanos , Mediadores da Inflamação/metabolismo , Transtornos da Memória/patologia , Ratos
15.
Hum Exp Toxicol ; 36(12): 1315-1325, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28111974

RESUMO

Impairment of memory is one of the most frequently reported symptoms during sudden hypoxia exposure in human. Cortical atrophy has been linked to the impaired memory function and is suggested to occur with chronic high-altitude exposure. However, the precise molecular mechanism(s) of hypoxia-induced memory impairment remains an enigma. In this work, we review hypoxia-induced learning and memory deficit in human and rat studies. Based on data from rat studies using different protocols of continuous hypoxia, we try to elicit potential mechanisms of hypobaric hypoxia-induced memory deficit.


Assuntos
Hipóxia , Aprendizagem/fisiologia , Oxigênio , Animais , Ratos
16.
Cryo Letters ; 38(4): 290-298, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29734430

RESUMO

  BACKGROUND: Conservation of commercially important ornamental plants is important to maintain its unique beauty to cater the market demands. OBJECTIVE: The main objective is to develop an efficient cryopreservation technique for Aranda Broga Blue orchid PLBs using droplet-vitrification method. MATERIALS AND METHODS: Several critical factors in cryopreservation were accessed such as preculture concentrations and durations, choice of vitrification solutions, two-step or three-step vitrification, growth recovery medium and PVS2 exposure duration. RESULTS: The best growth regeneration percentage (5%) was obtained when 3-4mm PLBs were precultured in 0.2M sucrose for 3 days, followed by osmoprotection for 20 minutes, dehydration in PVS2 for 20 minutes at 0 degree C, LN storage, thawed and unloading for 20 minutes, and growth regeneration in VW10 medium. PLBs were found to be very sensitive to osmotic stress imposed by high molecular weight cryoprotectant such as sucrose and glycerol. Osmotic potential of growth recovery medium is one of the main factors that affect growth recovery in cryopreserved PLBs. CONCLUSION: Current report showed possibilities in cryopreserving Aranda Broga Blue PLBs using droplet-vitrification technique. However, further improvement of growth recovery can be done by focussing on approaches that facilitate sufficient water removal from PLBs without causing severe osmotic injuries to the plant cells.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Orchidaceae/anatomia & histologia , Orchidaceae/fisiologia , Vitrificação , Meios de Cultura , Dessecação , Glicerol/farmacologia , Orchidaceae/efeitos dos fármacos , Pressão Osmótica , Regeneração/efeitos dos fármacos , Sacarose/farmacologia , Água/química
17.
Folia Biol (Praha) ; 62(5): 181-187, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27978412

RESUMO

Pineal melatonin biosynthesis is regulated by the circadian clock located in the suprachiasmatic nucleus of the hypothalamus. Melatonin has been found to modulate the learning and memory process in human as well as in animals. Endogenous melatonin modulates the process of newly acquired information into long-term memory, while melatonin treatment has been found to reduce memory deficits in elderly people and in various animal models. However, the mechanisms mediating the enhancing effect of melatonin on memory remain elusive. This review intends to explore the possible mechanisms by looking at previous data on the effects of melatonin treatment on memory performance in rodents.


Assuntos
Melatonina/farmacologia , Memória/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Humanos , Melatonina/uso terapêutico , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/fisiopatologia , Roedores
18.
Nanoscale ; 7(16): 7091-100, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25640454

RESUMO

High performance organic devices including polymer solar cells (PSCs) and light emitting diodes (PLEDs) were successfully demonstrated with the presence of highly ordered nanoimprinted Au nanodisks (Au NDs) in their solution-processed active/emissive layers, respectively. PSCs and PLEDs were fabricated using a low bandgap polymer and acceptor, nitrogen doped multiwalled carbon nanotubes poly[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno[3,4-b]-thiophenediyl] (n-MWCNTs:PTB7), and [6,6]-phenyl C71 butyric acid methyl ester (PC71BM) and (4,4-N,N-dicarbazole) biphenyl (CBP) doped with tris(2-phenylpyridine) iridium(iii) (Ir(ppy)3) as active/emissive layers, respectively. We synthesized nitrogen doped graphene and used it as anodic buffer layer in both devices. The localized surface plasmon resonance (LSPR) effect from Au NDs clearly contributed to the increase in light absorption/emission in the active layers from electromagnetic field enhancement, which originated from the excited LSPR in PSCs and PLEDs. In addition to the high density of LSPR and strong exciton-SP coupling, the electroluminescent (EL) enhancement is ascribed to enhanced spontaneous emission rates. This is due to the plasmonic near-field effect induced by Au NDs. The PSCs and PLEDs exhibited 14.98% (8.08% to 9.29%) under one sun of simulated air mass 1.5 global (AM1.5G) illumination (100 mW cm(-2)) and 19.18% (8.24 to 9.82 lm W(-1)) enhancement in the power conversion efficiencies (PCEs) compared to the control devices without Au NDs.

20.
Appl Opt ; 54(33): 9703-8, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26836526

RESUMO

This paper details the fabrication process for placing single-layer gold (Au) nanoparticles on a planar substrate, and investigation of the resulting optical properties that can be exploited for nonlinear optics applications. Preparation of Au nanoparticles on the substrate involved electron beam deposition and subsequent thermal dewetting. The obtained thin films of Au had a variation in thicknesses related to the controllable deposition time during the electron beam deposition process. These samples were then subjected to thermal annealing at 600°C to produce a randomly distributed layer of Au nanoparticles. Observation from field-effect scanning electron microscope (FESEM) images indicated the size of Au nanoparticles ranges from ∼13 to ∼48 nm. Details of the optical properties related to peak absorption of localized surface plasmon resonance (LSPR) of the nanoparticle were revealed by use of UV-Vis spectroscopy. The Z-scan technique was used to measure the nonlinear effects on the fabricated Au nanoparticle layers where it strongly relates LSPR and nonlinear optical properties.

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