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101.
102.
BACKGROUNDEfficient bone regeneration using recombinant human bone morphogenetic protein-2 (BMP-2) is needed to reduce side effects caused by high-dose BMP-2 use. The composite material of polylactic acid–polyethene glycol (PLA-PEG) for sustained release and an osteogenic nano-hydroxyapatite (nHAp) can contribute to efficient bone regeneration by BMP-2.STUDY DESIGNAn experimental in vitro and in vivo study.PURPOSEThe objective of this study is to investigate the effectiveness of a novel composite material of PLA-PEG and nHAp as a carrier for BMP-2.METHODSThe release kinetics of BMP-2 from the composites was investigated by ELISA. Thirty-six male Sprague–Dawley rats underwent posterolateral spinal fusion on L4–L5 with three different doses of BMP-2 (0 µg [control], 3 µg [low dose], and 10 µg [high dose]). Weekly µCT results and histology and a manual palpation test at 8 weeks postoperatively were used for assessment of the spinal fusion.RESULTSELISA demonstrated the sustained release of BMP-2 until day 21. µCT and manual palpation test demonstrated a solid fusion in 91.6% (11/12) of specimens in both the low- and high-dose groups. N mice in the control group attained bony fusion (0%, 0/9). nHAp was resorbed between 2 and 4 weeks postoperatively, and regenerated fusion mass at 8 weeks postoperatively consisted of only newly formed bone.CONCLUSIONSThe nHAp/PLA-PEG composite enabled efficient bone regeneration with low-dose BMP-2. The sustained release of BMP-2 by PLA-PEG and the osteogenic and biodegradable scaffold of nHAp might contribute to efficient bone regeneration.CLINICAL SIGNIFICANCEThis novel composite material has potential in clinical applications (spinal fusion, large bone defect and non-union) by enabling efficient bone formation by BMP-2.  相似文献   
103.

Purpose

To determine the impact of Gallium-68-labled prostate-specific membrane antigen positron-emission tomography/computed tomography ([68Ga]PSMA PET/CT) on radiotherapy planning for primary disease, biochemical cancer relapse, and advanced disease of prostate cancer.

Methods

A total of 106 patients with prostate cancer scheduled for radiation therapy underwent 120 [68Ga]PSMA PET/CT scans prior to radiotherapy treatment. In 20 cases, patients underwent [68Ga]PSMA PET/CT for primary therapy (PT), 75 cases were referred for biochemical relapse after surgery (RL), and 25 cases were intended for palliative treatment of localized metastases (MD). We retrospectively compared the impact of [68Ga]PSMA PET/CT on lesion detection and treatment decision to CT alone.

Results

[68Ga]PSMA PET/CT revealed a total of 271 positive lesions, whereas CT detected 86 lesions (32%). Overall, the radiotherapy regime was changed in 55 of 120 cases (46%) based on the higher detection rate of [68Ga]PSMA PET/CT: in 15% of cases with PT, in 43% of cases with RL, and in 44% of cases with MD.

Conclusion

[68Ga]PSMA PET/CT is superior to CT alone for lesion detection in prostate cancer, thereby significantly impacting on radiotherapy planning for primary disease, biochemical cancer relapse, and advanced disease of prostate cancer.
  相似文献   
104.
ABSTRACT

Silica is the second most common element after oxygen, and therefore, exposures to crystalline silica dust occur in a large variety of occupations such as metal foundries, constructions, and ceramic, quarry, and pottery industries. Since crystalline silica exposure has been linked with silicosis, lung cancer, and other pulmonary diseases, adverse effect attributed to this element has be a cause for concern worldwide. Silica dust exposure in workers is still considered to be important health problem especially in developing countries. The aim of the study was to investigate the effects of occupational silica exposure on oxidative stress parameters including the activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), and levels of total glutathione (GSH) and thiobarbituric acid reactive substance (TBARS) as well as immune system parameters such as interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, and IL-10 and tumor necrosis factor (TNF)-α in Turkish ceramic workers. In this study, nearly 50% of Turkish ceramic workers were diagnosed with silicosis. Eighty-four percent of these silicotic workers were found to present with profusion category 1 silicosis, whereas controls (n = 81) all displayed normal chest radiographs. Data demonstrated a significant decrease in levels of GSH and activities of CAT, SOD, and GPx, but a significant increase in MDA levels and activity of GR in all workers. Further, workers possessed significantly higher levels of IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-10, and TNF-α. These observations suggest that ceramic workers may have impaired antioxidant/oxidant status and activated immune system indicative of inflammatory responses.  相似文献   
105.
Background: The aim of the study was to explore the differences in oxidative stress during anesthesia with desflurane/N2O or propofol/remifentanil in patients undergoing laparoscopic cholecystectomy and additionally to evaluate the differential effects of desflurane and propofol on ischemic preconditioning (IP).

Materials and methods: One hundred patients were randomly allocated to four groups. For anesthesia maintenance, the inhalation group (Group I) and the inhalation plus IP group (Group IIP) received desflurane at an end-tidal concentration of 4–6 vol% in oxygen/N2O, and the TIVA group (Group T) and TIVA plus IP group (Group TIP) received infusions of propofol and remifentanil. In Groups IIP and TIP, IP was carried out by 10?min of pneumoperitoneum followed by 10?min of deflation. Preoperative and postoperative plasma total antioxidant status (TAS), total oxidant status (TOS), paraoxonase, stimulated paraoxonase, arylesterase, ceruloplasmin, and myeloperoxidase levels were analyzed; oxidative stress index (OSI) was calculated.

Results: When oxidative stress parameters were compared between groups, myeloperoxidase values in Group I were statistically significantly lower compared to Group TIP (p?=?.004 with Bonferroni’s correction). There were no differences between preoperative and postoperative TAS, paraoxonase, stimulated paraoxonase, arylesterase, or ceruloplasmin levels (p?>?.05). In intragroup evaluations, postoperative paraoxonase and stimulated paraoxonase levels were found to be lower than preoperative values in Group TIP (p?=?.021 and .012, respectively).

Conclusion: In laparoscopic cholecystectomy lasting less than 60?min, there were no differences in the measured oxidative stress parameters between maintenance of anesthesia by desflurane/N2O and propofol/remifentanil/N2O. The addition of 10?min IP administration during both anesthesia techniques did not result in additional changes in the analyzed oxidative stress.  相似文献   
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108.
Background: Hypomagnesemia could worsen glycemic control by impairing insulin release and promoting insulin resistance. On the contrary, type 2 diabetes mellitus (T2DM) may induce and/or exacerbate low serum magnesium levels, and this could, in turn, worsen glycemic control of diabetes.

Objective: The aim of this study was to investigate the relationship between serum magnesium level, dietary magnesium intake, and metabolic control parameters in patients with T2DM.

Methods: The study included 119 patients with T2DM (26 male, 93 female; mean age 54.7?±?8.4 years). Serum magnesium level was measured by spectrophotometric method. Magnesium intake was assessed by food frequency questionnaire. Anthropometric measurements were taken. The General Linear Model procedure was applied to determine the relationship of serum magnesium with quantitative variables.

Results: Of the 119 patients, 23.5% of the patients had inadequate magnesium intake (lower than 67% of the recommended daily allowance), and 18.5% had hypomagnesemia. In patients with hypomagnesemia (< 0.75?mmol/l), serum levels of fasting plasma glucose (FPG), postprandial plasma glucose (PPG), and serum glycosylated hemoglobin (HbA1c) were higher compared to patients with normomagnesemia. FPG levels were significantly higher in patients with hypomagnesemia in Model 1 (179.0?±?64.9 vs. 148.7?±?52.0?mg/dl, p?=?0.009) but the significance disappeared in other models. PPG levels were significantly higher in patients with hypomagnesemia in all models (287.9?±?108.4 vs. 226.8?±?89.4?mg/dl, p?=?0.006 for Model 1, p?=?0.027 for Model 2, p?=?0.016 for Model 3). Serum HbA1c levels were significantly higher in patients with hypomagnesemia, and this significance proceeded (8.0?±?1.9% vs. 6.5?±?1.2%, p?=?0.000 for all models). Body fat mass was significantly higher in patients with hypomagnesemia as compared to patients with normomagnesemia in model 3 (35.4?±?9.4?kg, 34.6?±?10.2?kg; p?=?0.034). Dietary magnesium intake was not significantly associated with either metabolic parameters or anthropometric measurements.

Conclusion: Hypomagnesemia in T2DM is directly associated with poor metabolic control. Clinical assessment should, therefore, focus on augmentation of magnesium status and adequate magnesium intake in patients with T2DM.  相似文献   

109.
Objective: Obesity is one of today’s most important public health problems. It is suggested that overeating and substance addiction show similarities, and addiction to food may be an important factor in the obesity epidemic. This study aimed to determine the prevalence of food addiction among schizophrenic patients and to examine the relationship between food addiction and anthropometric measurements and dietary nutrient intake.

Methods: Study participants included a total of 104 schizophrenic outpatients, 62 females and 42 males. Food addiction was assessed by using the Yale Food Addiction Scale, and the anthropometric measurements of participants and their three-day food consumption were recorded.

Results: This study found that more than half of the schizophrenic patients (60.6%) had food addiction, and that female schizophrenic patients had a higher prevalence (62.9%) of food addiction than male patients (57.1%). More than one-third of the schizophrenic patients with food addiction (41.3%) were found to be obese and their BMI, body weight, waist circumference, and body–fat ratio were higher than those of schizophrenic patients who did not have food addiction (P?>?0.05). Moreover, the schizophrenic patients with food addiction were found to take significantly more energy, carbohydrate, and fat in their diet (P?<?0.05).

Conclusion: It was observed that the development of food addiction in schizophrenic patients increased the risk of obesity and cardiovascular diseases, which were found to be at higher levels in these patients. Educational programs should be planned for these patients to acquire health dietary habits and to increase their physical activity levels, and an additional psychosocial support should be provided for patients with food addiction.  相似文献   

110.
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