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1.
J Mech Behav Biomed Mater ; 148: 106226, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37952506

RESUMO

Bioceramics, while offering excellent biocompatibility, are often compromised by their fragility and brittleness, especially under wet conditions. Even though recent hybrid processes combining biocompatible polymers and bioceramics have shown promise, complete mitigation of these challenges remains elusive. In this research, a biomimetic process was employed to mimic the structure of biological bone tissue. This led to the development of block materials composed of octacalcium phosphate (OCP) and sodium polyacrylic acid (PAA-Na) that display flexibility and resilience in wet conditions. Adjusting the PAA-Na concentration enabled the OCP-PAA-Na blocks to demonstrate superior mechanical strength when dry and increased flexibility when wet. Notably, these blocks expanded in aqueous solutions while preserving their structure, making them ideal for oral surgeries by preventing issues like blood flooding from implanted areas.


Assuntos
Fosfatos de Cálcio , Polímeros , Fosfatos de Cálcio/química , Osso e Ossos , Cimentos Ósseos , Regeneração Óssea
2.
Phys Chem Chem Phys ; 25(39): 26640-26647, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37772427

RESUMO

Octacalcium phosphate (OCP), a precursor to apatite, has a layered structure that allows various molecules to be intercalated within its interlayers. Previous research on the phase conversion process of OCP to apatite indicated that the layered structures typically collapse due to the shrinking of the OCP layers. In contrast, this study presents a novel phenomenon involving OCP layer expansion during phase conversion. This expansion is based on a forced oxidation process of the intercalated molecules within the hydrous layers of OCP. By introducing NaClO to an OCP interlayer containing dithiodiglycolic acid (DSG), the OCP layers are expanded. This process involves DSG decomposition through its reaction with NaClO. Specifically, the process occurs when a DSG-substituted OCP (containing disulfide bonds (-S-S-)) is immersed in a NaClO solution. This is the first study to report the expansion phenomenon during the phase conversion process from OCP to apatite, providing a new perspective to the conventional understanding that these layers only shrink.

3.
ACS Omega ; 8(24): 21464-21473, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37360484

RESUMO

In nature, minerals record various origins and information for geology and geobiochemistry. Here, we investigated the origin of organic matter and growth mechanism of quartz with oil inclusion revealing fluorescence under short ultraviolet (UV) light, obtained from the clay vein at Shimanto-cho, Kochi, Shikoku Island, Japan. Geological investigation indicated that the oil-quartz was formed in hydrothermal metamorphic veins found in the late Cretaceous interbedded sandstone and mudstone. The obtained oil-quartz crystals are mostly double-terminated. Micro-X-ray computed tomography (microCT) indicated that oil-quartz crystals have various veins originating as skeleton structures along the quartz crystal {111} and {1-11} faces. Spectroscopic and chromatographic studies indicated that aromatic ester and tetraterpene (lycopene) molecules, which revealed fluorescence, were detected. Large molecular weight sterol molecules, such as C40, were also detected in the vein of oil-quartz. This investigation indicated that organic inclusions in mineral crystals would form with ancient microorganism culture environments.

4.
Clin Pract ; 12(3): 306-317, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35645313

RESUMO

Background: Treatment of high blood pressure is a combination of lifestyle changes and medications, and appropriateexercise therapy is recommended as one of the lifestyle-related changes. Recently, stretching, a low-intensity exercise, was reported to be antihypertensive and effective for improving arteriosclerosis, in addition to aerobic exercise. The present study investigated the short-term effects of continuous stretching and rest-induced rebound on vascular endothelial function in hypertensive patients. Methods: This study was conducted as a single-arm prospective interventional study including patients between 30 and 70 years of age undergoing treatment for hypertension from October 2019 until May 2021. The intervention consisted of six months of daily stretching, one month of rest, and another three months of stretching. We measured arteriosclerosis indices such as cardio ankle vascular index (CAVI), ankle brachial pressure index (ABI) and reactive hyperemia index (RHI), and flexibility at the baseline and one, three, six, seven, and ten months from the baseline. Results: We included a total of ten patients (three males and seven females) with an average age of 60.10 ± 6.05 years. The exercise rate for the entire period was 90% or more, and the anteflexion measurement value improved significantly before and after the intervention (p < 0.001). Blood pressure and CAVI/ABI were well controlled throughout the study period. RHI did not show any significant improvement during the initial six months, and only slightly improved by the third month (p = 0.063). Even after the rest phase and resumption of stretching, RHI remained stable. Conclusions: The compliance of the stretching program we used, evaluated by the exercise implementation rate for the entire period, was 90% or more; therefore, easy to perform and continue by hypertensive patients. However, we did not observe a significant positive effect on arteriosclerosis index or blood pressure in this study.

5.
J Clin Med Res ; 11(12): 834-841, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31803328

RESUMO

BACKGROUND: Intensive care unit-acquired weakness (ICU-AW) can be diagnosed using the Medical Research Council (MRC) score. However, such scoring may not be possible in ICU patients who may be sedated or delirious or have encephalopathy. Currently, a quantitative assessment of the cross-sectional area of the muscle is available to assess changes in skeletal muscle mass using computed tomography (CT) images. This assessment calculates the skeletal muscle index (SMI) (cm2/m2) by dividing the cross-sectional area (cm2) of the skeletal muscle at the level of the third lumbar vertebra by the square of the patient's height (m2) on CT. This study assessed the effectiveness of SMI, as measured by abdominal CT scans, in predicting the onset of ICU-AW in patients with sepsis admitted to the ICU. METHODS: We examined septic ICU patients admitted to the Niigata University Hospital ICU during 2012 - 2017 under mechanical ventilation. Patients were retrospectively divided into two groups by MRC score at ICU discharge: group AW comprised patients with an MRC score < 48, and group non-AW (NAW) comprised the remaining patients. Clinicopathological factors at ICU admission such as age, gender, underlying disease, body mass index, and SMI were compared between the two groups. Statistical analyses were performed using the Mann-Whitney U test, Fisher's exact test, receiver operator characteristic (ROC) analysis and multivariate analysis. RESULTS: A total of 31 septic patients were examined, and 23 patients met the criteria for ICU-AW. The prevalence of women was significantly higher in group AW (P < 0.05). All clinical factors, except for gender, were not significantly different between the two groups. SMI was significantly lower in group AW than in group NAW (P < 0.05). ROC analysis revealed that the cut-off value of SMI for predicting ICU-AW was 44.1, and the multivariate analysis revealed that only low SMI was a significant factor in predicting ICU-AW (P < 0.05). CONCLUSIONS: Our results show that SMI measurement at ICU admission is a valid predictive factor for ICU-AW progression in septic patients.

6.
J Clin Med Res ; 11(10): 711-719, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31636786

RESUMO

BACKGROUND: Sarcopenia is a prognostic factor for patients with liver cirrhosis and hepatocellular carcinoma, and it affects the onset of hepatic encephalopathy. Therefore, the prevention of sarcopenia contributes to the improvement of the prognosis of patients with chronic liver disease (CLD). We focused on changes of hand grip strength (HGS), one of the indicators of sarcopenia. However, there are little data investigating the impact of physical activity (PA) on HGS in patients with CLD. This study aimed to clarify whether PA contributes to the prevention of muscle weakness in patients with CLD. METHODS: This was a prospective observational study. We examined the effect of PA on changes in HGS from the baseline to the endpoint in each group. Metabolic equivalents-hour/week (METs-h/w) was used to evaluate PA. In total, 183 outpatients with CLD were analyzed. We divided participants into four groups (low PA in younger patients (n = 20), high PA in younger patients (n = 33), low PA in elderly patients (n = 47), and high PA in elderly patients (n = 83)). RESULTS: Fifty-eight percent of patients were men, and the median (interquartile range) age was 69.0 (63.0, 75.0) years. The most common etiology of liver disease was hepatitis C (38%). The frequency of living alone and low exercise habit was significantly high, and sarcopenia was more obvious in elderly patients with low PA than in those with high PA. Additionally, the elderly with low PA showed significantly reduced HGS compared to that of the elderly with high PA (-1.00 (-2.27, 0.55) kg vs. 0.10 (-1.40, 1.10) kg, P < 0.05). However, changes in HGS in younger patients were not significant (-0.02 (1.83, 1.47) kg vs. 0.25 (-2.45, 2.05) kg, P = 0.96). Logistic regression analyses identified PA as the independent factor for prevention of decrease in HGS (odds ratio: 1.91, 95% confidence interval: 1.00 - 3.62, P = 0.049). CONCLUSIONS: Young patients with low PA were characterized by a long sedentary time; however, there was no loss of HGS. In contrast, elderly patients with CLD and low PA had significantly reduced HGS compared to that in elderly patients with CLD and high PA.

7.
J Clin Med Res ; 10(12): 920-927, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30425765

RESUMO

BACKGROUND: Sarcopenia can affect the prognosis of patients with cirrhosis or hepatocellular carcinoma. Exercise therapy and nutritional therapy are carried out to prevent processing sarcopenia. In addition, changing lifestyle is also important. However, there are only few reports on the physical activities (PAs) and lifestyle of chronic liver disease patients and their association with sarcopenia. The aim of this study is to examine the relationship between sarcopenia in patients with chronic liver disease and both PA and lifestyle. METHODS: A total of 214 out-patients with chronic liver disease were enrolled into the present study. All patients were evaluated for with or without sarcopenia based on the sarcopenia diagnostic criteria of the Japan Society of Hepatology. Then, patient's characteristics and laboratory parameters were divided into two groups with or without sarcopenia and compared. In continuous variable with significant difference in univariate analysis, cut-off value was calculated by receiver operating characteristic curve. We determined which factors were associated with sarcopenia in univariate analyses, and variables significant in the univariate analyses were entered in a multivariable logistic regression model. RESULTS: Patients with chronic liver disease had a prevalence of sarcopenia of 12.6% in this study. Sarcopenia patients were older (76.48 ± 6.69 versus 66.97 ± 11.19 years old; P < 0.01), had lower body mass index (BMI) (20.84 ± 2.44 versus 23.76 ± 3.72 kg/m2; P < 0.01), lower PA (6.6 (2.34 - 19.90) versus 16.5 (6.60 - 41.23) metabolic equivalents (METs)-h/week; P < 0.01) and longer total time sitting and lying on the day (7.43 ± 4.09 versus 5.68 ± 3.17 h/day; P = 0.01); retirement status (81.5% versus 48.1%; P < 0.01) and low frequency of driving (40% versus 20%; P = 0.01) were higher in sarcopenia patients than in non-sarcopenia patients. The independent predictive factors of sarcopenia, analyzed with logistic regression, were age (odds ratio (OR): 5.89, 95% confidence interval (CI): 2.15 - 16.20; P < 0.01), BMI (OR: 4.77, 95% CI: 1.87 - 12.10; P < 0.01) and PA (OR: 3.65, 95% CI: 2.15 - 16.20; P < 0.01). CONCLUSION: Sarcopenia patients' lifestyle characteristics were longer sedentary time and low frequency of driving, high retirement. Independent predictive factors of sarcopenia were elderly, low BMI and low PA. For these patients, intervention in the lifestyle for prevention of sarcopenia may be effective for patients with chronic liver disease.

8.
Nutrients ; 10(11)2018 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-30373264

RESUMO

Micronutrients include vitamins, minerals and, trace elements that are required in minute quantities but play a vital role in normal human growth, development and physiological functioning. Micronutrient deficiencies, also known as hidden hunger, are a global issue, with particularly high prevalence rates in developing countries. Currently, Sri Lanka is experiencing the double burden of over- and undernutrition. This review describes the micronutrient status of Sri Lanka based on results of national surveys and related articles published from 2000. The available data suggest a higher prevalence of iron, zinc, calcium, folate, and vitamin A deficiencies. The prevalence of iodine deficiency has declined gradually following the implementation of a universal salt iodization program. Iron deficiency is the most common cause of anemia and low red blood cell indices. Females are more vulnerable to micronutrient deficiencies than males. The coexistence of multiple micronutrient deficiencies and concurrent macro- and micronutrient deficiencies is common. Studies have shown an association between micronutrient deficiencies and different demographic, socioeconomic, and dietary factors. Therefore, there is a need for comprehensive studies, nutritional policies, and nationwide intervention programs in Sri Lanka to improve the micronutrient status of the population.


Assuntos
Micronutrientes , Estado Nutricional , Humanos , Desnutrição/epidemiologia , Política Nutricional , Sri Lanka/epidemiologia
9.
J UOEH ; 27(1): 41-62, 2005 Mar 01.
Artigo em Japonês | MEDLINE | ID: mdl-15794591

RESUMO

The purpose of our study was to investigate the social support network for working mothers, including physical, emotional and informational sources, and to discuss strategies to reduce stress caused by their multiple role strain. We asked 18 participants to fill in a questionnaire and conducted semi-constructed interviews. The results of this study showed that more than half of the working mothers want to continue their career because of self growth and the rewards from their job. Many mothers responded that a sympathetic understanding by their husbands, families and people at workplaces is essential to create a balance between their career and housework. As a result, their husbands mainly provide physical support in housekeeping and child caring, whereas their mothers provide physical and emotional support from knowledge based upon their own experience. Almost all working mothers complained of a shortage of nurseries and child caring facilities as well as limited availability of flexible services. In conclusion, the results of our study suggested that the identity of the traditional gender role needs to be changed to a contemporary one, like a husband fully participating in his child's rearing activities by reconsidering his working hours. Moreover, community services to support working mothers should be increased.


Assuntos
Relações Interpessoais , Mães , Meio Social , Apoio Social , Mulheres Trabalhadoras , Adulto , Criança , Educação Infantil , Pré-Escolar , Redes Comunitárias , Feminino , Zeladoria , Humanos , Pessoa de Meia-Idade , Mães/psicologia , Inquéritos e Questionários
10.
Biomaterials ; 25(16): 3267-73, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14980421

RESUMO

Poly(ethylene glycol) (PEG) derivative having both carboxylic acid-, and lactose-side chains (Lac-PEG-C) deposited onto the surface of DNA/protamine (PRT) complex, and the self-assembled ternary complex was obtained. The diameter of the complexes was 180-200 nm, and they showed good size stability even in the high ionic strength solutions. Lac-PEG-C coating reduced their surface electric potential, and effectively avoided the albumin-induced aggregation. DNA/PRT/Lac-PEG-C complex did not coagulate the red blood cells, and their cytotoxicity evaluated by WST-1 was very low. Lac-PEG-C added to the plasmid/PRT complex prior to the incubation with HepG2 cells extremely enhanced the gene-expression, and by the plasmid/PRT/Lac-PEG-C complex prepared at 1:1.5:8 in weight, 56-fold higher expression of luciferase than that without Lac-PEG-C was observed. The treatment with asialofetuin or phenylarsine oxide evidently interfered with the gene-expression. The high gene expression by the plasmid/PRT/Lac-PEG-C ternary complex on the hepatocyte would be attributed to the asialoglycoprotein receptor-mediated endocytosis.


Assuntos
Carcinoma Hepatocelular/genética , Materiais Revestidos Biocompatíveis/química , Sistemas de Liberação de Medicamentos/métodos , Técnicas de Transferência de Genes , Lactose/química , Plasmídeos/administração & dosagem , Polietilenoglicóis/química , Protaminas/química , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Marcação de Genes/métodos , Terapia Genética/métodos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Teste de Materiais , Plasmídeos/química , Transfecção/métodos
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