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For commercial processes, through-hole AAO membranes are fabricated from high-purity aluminum by chemical etching. However, this method has the disadvantages of using heavy-metal solutions, creating large amounts of material waste, and leading to an irregular pore structure. Through-hole porous alumina membrane fabrication has been widely investigated due to applications in filters, nanomaterial synthesis, and surface-enhanced Raman scattering. There are several means to obtain freestanding through-hole AAO membranes, but a fast, low-cost, and repetitive process to create complete, high-quality membranes has not yet been established. Here, we propose a rapid and efficient method for the multi-detachment of an AAO membrane at room temperature by integrating the one-time potentiostatic (OTP) method and two-step electrochemical polishing. Economical commercial AA1050 was used instead of traditional high-cost high-purity aluminum for AAO membrane fabrication at 25 °C. The OTP method, which is a single-step process, was applied to achieve a high-quality membrane with unimodal pore distribution and diameters between 35 and 40 nm, maintaining a high consistency over five repetitions. To repeatedly detach the AAO membrane, two-step electrochemical polishing was developed to minimize damage on the AA1050 substrate caused by membrane separation. The mechanism for creating AAO membranes using the OTP method can be divided into three major components, including the Joule heating effect, the dissolution of the barrier layer, and stress effects. The stress is attributed to two factors: bubble formation and the difference in the coefficient of thermal expansion between the AAO membrane and the Al substrate. This highly efficient AAO membrane detachment method will facilitate the rapid production and applications of AAO films.
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Anodic aluminum oxide (AAO) has been widely applied for the surface protection of electronic component packaging through a pore-sealing process, with the enhanced hardness value reaching around 400 Vickers hardness (HV). However, the traditional AAO fabrication at 0~10 °C for surface protection takes at least 3-6 h for the reaction or other complicated methods used for the pore-sealing process, including boiling-water sealing, oil sealing, or salt-compound sealing. With the increasing development of nanostructured AAO, there is a growing interest in improving hardness without pore sealing, in order to leverage the characteristics of porous AAO and surface protection properties simultaneously. Here, we investigate the effect of voltage on hardness under the same AAO thickness conditions in oxalic acid at room temperature from a normal level of 40 V to a high level of 100 V and found a positive correlation between surface hardness and voltage. The surface hardness values of AAO formed at 100 V reach about 423 HV without pore sealing in 30 min. By employing a hybrid pulse anodization (HPA) method, we are able to prevent the high-voltage burning effect and complete the anodization process at room temperature. The mechanism behind this can be explained by the porosity and photoluminescence (PL) intensity of AAO. For the same thickness of AAO from 40~100 V, increasing the anodizing voltage decreases both the porosity and PL intensity, indicating a reduction in pores, as well as anion and oxygen vacancy defects, due to rapid AAO growth. This reduction in defects in the AAO film leads to an increase in hardness, allowing us to significantly enhance AAO hardness without a pore-sealing process. This offers an effective hardness enhancement in AAO under economically feasible conditions for the application of hard coatings and protective films.
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Nanoporous anodic aluminum oxide (AAO) is an important template for 1D nanomaterial synthesis. It is used as an etching template for nanopattern transfer in a variety of contexts, including nanostructured material synthesis, electrical sensors, optical sensors, photonic and electronic devices, photocatalysis, and hardness and anticorrosion improvement. In this review, we focus on various fabrication methods, pore geometry modification, and recent advances of AAO, as well as sensor applications linked to our environment, daily life, and safety. Pore geometry is concerned with the material composition, applied voltage mold, electrolyte type, temperature, and anodizing time during the fabrication of AAOs and for adjusting their pore size and profile. The applied voltage can be divided into four types: direct current anodization (DCA), reverse pulse anodization, pulse anodization (PA), and hybrid pulse anodization (HPA). Conventional AAOs are fabricated using DCA and mild anodization (MA) at a relatively low temperature (-5~15 °C) to reduce the Joule heating effect. Moreover, the issues of costly high-purity aluminum and a long processing time can be improved using HPA to diminish the Joule heating effect at relatively high temperatures of 20-30 °C with cheap low-purity (≤99%) aluminum. The AAO-based sensors discussed here are primarily divided into electrical sensors and optical sensors; the performance of both sensors is affected by the sensing material and pore geometry. The electrical sensor is usually used for humidity or gas measurement applications and has a thin metal film on the surface as an electrode. On the contrary, the AAO optical sensor is a well-known sensor for detecting various substances with four kinds of mechanisms: interference, photoluminescence, surface plasma resonance, and surface-enhanced Raman scattering (SERS). Especially for SERS mechanisms, AAO can be used either as a solid support for coating metal nanoparticles or a template for depositing the metal content through the nanopores to form the nanodots or nanowires for detecting substances. High-performance sensors will play a crucial role in our living environments and promote our quality of life in the future.
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Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease. Usually, patients survive for approximately 2-4 years after the onset of the disease, and they often die of respiratory failure. This study examined the factors associated with signing a "do not resuscitate" (DNR) form in patients with ALS. This cross-sectional study included patients diagnosed with ALS between January 2015 and December 2019 in a Taipei City hospital. We recorded patients' age at disease onset; sex; presence of diabetes mellitus, hypertension, cancer, or depression; use of invasive positive pressure ventilator (IPPV) or non-IPPV (NIPPV); use of nasogastric tube (NG) or percutaneous endoscopic gastrostomy (PEG) tube; follow-up years; and number of hospitalizations. Data from 162 patients were recorded (99 men). Fifty-six (34.6%) signed a DNR. Multivariate logistic regression analyses revealed that the factors associated with DNR included NIPPV (OR = 6.95, 95% CI = 2.21-21.84), PEG tube feeding (OR = 2.86, 95% CI = 1.13-7.24), NG tube feeding (OR = 5.75, 95% CI = 1.77-18.65), follow-up years (OR = 1.13, 95% CI = 1.02-1.26), and number of hospital admissions (OR = 1.26, 95% CI = 1.02-1.57). The findings suggest that end-of-life decision making among patients with ALS may often be delayed. DNR decisions should be discussed with patients and their families during the early stages of disease progression. Physicians are advised to discuss DNR with patients when they can speak and to offer palliative care options.
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Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Masculino , Humanos , Ordens quanto à Conduta (Ética Médica) , Esclerose Lateral Amiotrófica/terapia , Esclerose Lateral Amiotrófica/complicações , Taiwan/epidemiologia , Estudos Transversais , Doenças Neurodegenerativas/complicações , Morte , Estudos RetrospectivosRESUMO
OBJECTIVE: The main objective of this study was to evaluate the efficacy and safety of Lactobacillus rhamnosus in children aged 4-48 months with atopic dermatitis. METHODS: The design of this study was a two-center, double-blind, randomized, and placebo-controlled study with two parallel groups to evaluate the efficacy and safety profile of L. rhamnosus in children aged 4-48 months with atopic dermatitis diagnosed using Hanifin and Rajka criteria and with a Scoring of Atopic Dermatitis (SCORAD) ≥ 15 at enrollment. The duration of this study was 8 weeks with a total of five visits. The enrolled patients were allocated into either a treatment group (one ComProbi capsule containing L. rhamnosus a day) or a control group (one capsule of placebo a day) at a ratio of 1:1. The primary endpoint was to compare the mean change from baseline in SCORAD after 8 weeks of treatment. The other secondary end points were to compare the following: the mean changes from baseline in SCORAD at postbaseline visits, the frequency and total amount of the use of corticosteroids during the 8-week treatment, the frequency of atopic dermatitis and the symptom-free duration, the mean changes from baseline in Infant Dermatitis Quality of Life Questionnaire at Week 4 and Week 8, and the mean changes from baseline in the Dermatitis Family Impact Questionnaire at Week 4 and Week 8. RESULTS: The mean changes in SCORAD from baseline at Week 8 was -21.69 ± 16.56 in the L. rhamnosus group and -12.35 ± 12.82 in the placebo group for the intent-to-treat population (p = 0.014). For the per-protocol population, the mean change of SCORAD from baseline was -23.20 ± 15.24 in the L. rhamnosus group and -12.35 ± 12.82 in the placebo group (p = 0.003). Significant differences were demonstrated between groups at Week 8 in intensity in the intent-to-treat population and per-protocol population. Throughout the period, the amount of topical corticosteroids used showed no difference between groups. No significant difference was noted in the overall symptom-free durations compared with the placebo group. Infant Dermatitis Quality of Life Questionnaires and Dermatitis Family Impact Questionnaires scores improved significantly at Week 4 and Week 8 but did not reach statistical significance. Adverse events were documented in 14/33 patients in the L. rhamnosus group (42.42%, 35 events) and in 15/33 placebo patients (45.45%, 37 events). CONCLUSIONS: The results of this study indicated that L. rhamnosus was effective in decreasing symptoms of atopic dermatitis after an 8-week treatment by comparing the mean change of SCORAD from baseline with a placebo (p < 0.05). The reduction in SCORAD resulted from a consistent decrease in all components of SCORAD. Patients who took L. rhamnosus for 8 weeks expressed less SCORAD in the three components: area of affected skin, intensity of atopic dermatitis, and patient symptoms, with a significant decrease in the mean change of intensity from baseline compared with placebo.
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Dermatite Atópica/terapia , Lacticaseibacillus rhamnosus/fisiologia , Probióticos/uso terapêutico , Corticosteroides/uso terapêutico , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Lactente , Masculino , Pais , Placebos , Qualidade de Vida , Índice de Gravidade de Doença , Inquéritos e Questionários , Taiwan , Resultado do TratamentoRESUMO
Hydrocarbon vents have recently been reported to contribute considerable amounts of dissolved organic carbon (DOC) to the oceans. Many such hydrocarbon vents widely exist in the northern South China Sea (NSCS). To investigate if these hydrocarbon vent sites release DOC, we used a real-time video multiple-corer to collect bottom seawater and surface sediments at vent sites. We analyzed concentrations of DOC in these samples and estimated DOC fluxes. Elevated DOC concentrations in the porewaters were found at some sites suggesting that DOC may come from these hydrocarbon vents. Benthic fluxes of DOC from these sediments were 28 to 1264 µmol m(-2 )d(-1) (on average ~321 µmol m(-2 )d(-1)) which are several times higher than most DOC fluxes in coastal and continental margin sediments. The results demonstrate that the real-time video multiple-corer can precisely collect samples at vent sites. The estimated benthic DOC flux from the methane venting sites (8.6 × 10(6 )mol y(-1)), is 24% of the DOC discharge from the Pearl River to the South China Sea, indicating that these sediments make an important contribution to the DOC in deep waters.
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Ageing, which all creatures must encounter, is a challenge to every living organism. In the human body, it is estimated that cell division and metabolism occurs exuberantly until about 25 years of age. Beyond this age, subsidiary products of metabolism and cell damage accumulate, and the phenotypes of ageing appear, causing disease formation. Among these age-related diseases, neurodegenerative diseases have drawn a lot of attention due to their irreversibility, lack of effective treatment, and accompanied social and economical burdens. In seeking to ameliorate ageing and age-related diseases, the search for anti-ageing drugs has been of much interest. Numerous studies have shown that the plant polyphenol, resveratrol (3,5,4'-trihydroxystilbene), extends the lifespan of several species, prevents age-related diseases, and possesses anti-inflammatory, and anti-cancer properties. The beneficial effects of resveratrol are believed to be associated with the activation of a longevity gene, SirT1. In this review, we discuss the pathogenesis of age-related neurodegenerative diseases including Alzheimer's disease, Parkinson's disease and cerebrovascular disease. The therapeutic potential of resveratrol, diet and the roles of stem cell therapy are discussed to provide a better understanding of the ageing mystery.
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Envelhecimento/fisiologia , Longevidade/fisiologia , Doenças Neurodegenerativas/fisiopatologia , Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Humanos , Longevidade/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Resveratrol , Estilbenos/farmacologia , Estilbenos/uso terapêuticoRESUMO
Stem cells, a special subset of cells derived from embryo or adult tissues, are known to present the characteristics of self-renewal, multiple lineages of differentiation, high plastic capability, and long-term maintenance. Recent reports have further suggested that neural stem cells (NSCs) derived from the adult hippocampal and subventricular regions possess the utilizing potential to develop the transplantation strategies and to screen the candidate agents for neurogenesis, neuroprotection, and neuroplasticity in neurodegenerative diseases. In this article, we review the roles of NSCs and other stem cells in neuroprotective and neurorestorative therapies for neurological and psychiatric diseases. We show the evidences that NSCs play the key roles involved in the pathogenesis of several neurodegenerative disorders, including depression, stroke and Parkinson's disease. Moreover, the potential and possible utilities of induced pluripotent stem cells (iPS), reprogramming from adult fibroblasts with ectopic expression of four embryonic genes, are also reviewed and further discussed. An understanding of the biophysiology of stem cells could help us elucidate the pathogenicity and develop new treatments for neurodegenerative disorders. In contrast to cell transplantation therapies, the application of stem cells can further provide a platform for drug discovery and small molecular testing, including Chinese herbal medicines. In addition, the high-throughput stem cell-based systems can be used to elucidate the mechanisms of neuroprotective candidates in translation medical research for neurodegenerative diseases.
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Células-Tronco Adultas/transplante , Hipocampo/metabolismo , Células-Tronco Neurais/transplante , Doenças Neurodegenerativas/terapia , Medicina Regenerativa/métodos , Transplante de Células-Tronco , Células-Tronco Adultas/metabolismo , Células-Tronco Adultas/patologia , Animais , Hipocampo/patologia , Humanos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologiaRESUMO
We report the case of a 77-year-old immuno-competent man who developed herpes zoster in the maxillary and mandibular branches of the trigeminal nerve. Within 3 weeks, he developed ipsilateral peripheral facial palsy, hearing loss, vesicles over the external auditory canal, and pain in the face and ear. A T(2)-weighted MRI of the brain revealed a hyper-intense lesion at the right medulla corresponding to the spinal trigeminal nucleus and tract. Gadolinium enhancement was seen over the right facial nerve. These lesions suggest a possibility of transaxonal spread of the varicella zoster virus between the trigeminal nerve, the facial nerve, and the spinal trigeminal nucleus and tract.
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Herpes Zoster da Orelha Externa/patologia , Herpes Zoster/patologia , Doenças do Nervo Trigêmeo/patologia , Núcleo Espinal do Trigêmeo/patologia , Idoso , Encéfalo/patologia , Nervo Facial/patologia , Herpes Zoster/complicações , Herpes Zoster da Orelha Externa/complicações , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/patologia , Doenças do Nervo Trigêmeo/complicaçõesRESUMO
Different types of symptomatic trigeminal autonomic cephalalgias (TACs) have been reported in patients with pituitary adenoma. We investigated the significance of the presence of cranial autonomic symptoms (CAS) in patients with pituitary adenoma presenting with headaches. The records of patients with pituitary adenoma from 1998 to 2004 in our headache clinic were reviewed including headache profile, presence or absence of CAS, and the characteristics of the pituitary adenoma. CAS were ascertained if one or more autonomic symptoms defined for the diagnosis of TACs in the International Classification of Headache Disorders, 2nd edition (ICHD-2) was identified. Thirty-three patients (24F/9M) with pituitary adenoma presenting with headache were recruited for this study: 18 with CAS (55%) and 15 without. Chronic migraine was the most common headache phenotype (n=16, 48%). Three patients were diagnosed as hemicrania continua-like and three, cluster headache-like. In the group with CAS (CAS+), the sides of the tumor were significantly concordant with the sides of headaches (kappa=0.58, p<0.001) and those of CAS (kappa=0.67, p<0.001). However, this relationship was not demonstrated in those without CAS (CAS-) (kappa=0.07, p=0.61). Compared with the patients in the CAS- group, the patients in the CAS+ group had higher frequencies of macroadenoma (78% vs. 40%, p=0.027) and acromegaly (50% vs. 7%, p=0.009). The presence and absence of CAS in pituitary adenoma-associated headache were associated with different characteristics of the underlying pituitary adenomas including side concordance and incidence of acromegaly and macroadenoma. The pathogeneses for headache might differ between these two groups.
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Adenoma/complicações , Doenças do Sistema Nervoso Autônomo/complicações , Doenças dos Nervos Cranianos/complicações , Cefaleia/etiologia , Neoplasias Hipofisárias/complicações , Acromegalia/etiologia , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cefalalgias Autonômicas do Trigêmeo/etiologiaRESUMO
UNLABELLED: Rotavirus is a leading cause of gastroenteritis in young children, which may indicate hospitalization due to dehydration and electrolyte imbalance. Most cases are self-limited with good prognosis. The association between rotavirus and toxic megacolon has never been mentioned in the literature. We report a case of toxic megacolon secondary to rotavirus gastroenteritis. CONCLUSION: Toxic megacolon can occur in patients with rotavirus gastroenteritis. An abdominal radiograph should be taken for patients with rotavirus gastroenteritis who have systemic toxicity and persistent abdominal fullness.