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61.
Ascorbic acid (vitamin C) is an antioxidant that is widely used in cosmetics in skincare products. Due to the excessive low stability of ascorbic acid in cosmetic formulations, the stabilized ascorbic acid derivative, magnesium ascorbyl phosphate (MAP) was formulated as vesicular carriers; ethosomes and niosomes. The aim was to deliver MAP at the intended site of action, the skin, for sufficient time with enhanced permeation to get an effective response. Ethosomes were formulated using a full 32 factorial design to study ethanol and phospholipid concentration effect on ethosomes properties. Niosomes were formulated using 23 factorial designs to study the effect of surfactant type, surfactant concentration and cholesterol concentration on niosomes properties. The prepared formulations were evaluated for their Entrapment efficiency, particle size, polydispersity index, zeta potential and % drug permeated. The optimized ethosomal and niosomal formulations were incorporated into carbopol gel and evaluated for their permeation, skin retention and stability. A comparative split-face clinical study was done between the ethosomal and niosomal formulations for melasma treatment using Antera 3 D® camera. The optimized ethosomal and niosomal gels showed comparable controlled permeation and higher skin retention over their ethosomes and niosomes formulations respectively. Magnesium ascorbyl phosphate ethosomal gel showed clinically and statistically significant melanin level decrease after one month while MAP niosomal gel showed clinically and statistically significant melanin level decrease after six months. A combination of MAP ethosomes and niosomes could be promising skincare formulations for melasma and hyperpigmentation short and long-term treatment.  相似文献   
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Digestive Diseases and Sciences - Crohn’s disease (CD) of the pouch and chronic pouchitis represent the most common long-term complications of total proctocolectomy and ileal pouch anal...  相似文献   
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Objective To compare subsequent endometriosis-related surgery following initial laparoscopy among women treated with leuprolide acetate (LA) or other endometriosis therapies versus women who received no pharmacotherapy.

Research design and methods This retrospective cohort analysis utilized MarketScan Commercial claims data. Women with endometriosis aged 18–49 who underwent laparoscopy between 1 January 2005 and 31 December 2011 were identified using diagnosis and procedures codes and were categorized into four cohorts based on claims within 90 days of laparoscopy: surgery plus adherent LA, surgery plus non-adherent LA, surgery plus other therapy, and surgery alone. Patients with proportion of days covered ≥0.80 in the 6 months after laparoscopy were considered adherent to LA.

Main outcome measures Subsequent endometriosis-related surgery (laparoscopy, laparotomy or other excision/ablation/fulguration of endometriosis lesions, oophorectomy, or hysterectomy) was measured in the 6 and 12 months following initial laparoscopy. Risk of subsequent surgery was compared using multivariable Cox proportional hazards modeling.

Results Most women were treated with surgery only (n?=?9865); fewer were treated with LA (adherent: n?=?202; non-adherent: n?=?490) or other therapies (n?=?230). The proportion of patients with subsequent surgery ranged from 2.0% to 10.0% during the 6 month follow-up (12 month: 9.7% to 13.5%). Adherent LA use was associated with significantly lower risk of surgery compared to surgery alone (hazard ratio [HR]?=?0.31, p?=?0.020) while use of other therapies was associated with significantly higher risk (HR = 1.51, p?=?0.045) over the 6 month follow-up. There was no significant difference between the surgery plus non-adherent LA and surgery only cohort over 6 months (p?=?0.247). The association between adherent LA and subsequent surgery was not significant over the 12 month follow-up.

Conclusion Therapy with LA after laparoscopy for endometriosis was associated with lower risk of subsequent surgery at 6 months among women who were adherent to LA. Key limitations include lack of ability to capture disease severity which may have resulted in uncontrolled confounding.  相似文献   
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BACKGROUND: A number of experimental studies have shown that increasing glucose use or decreasing accumulation of long-chain acyl carnitines (LCAC) protect ischemic hearts. METHODS: To evaluate the relative importance of these two strategies in protecting ischemic myocardium, isolated rat hearts (n = 6 in each group) were paced at 300 bpm and subjected to 50 min of low-flow ischemia followed by 60 min of reperfusion. Buffer contained 0.4 m mol/l albumin, 0.4 m mol/l palmitate, and 70 mU/l insulin, and either normal glucose (5 m mol/l) (CON), high glucose (10 m mol/l total) (HG, known to increase glucose use), 5 m mol/l glucose and niacin (10 micromol/l) (NIA, known to increase glucose use and decrease LCAC) or carnitine (10 m mol/l) (CAR, known to increase glucose use and decrease LCAC). Separate groups of hearts were perfused in the presence of 10 micromol/l cytochalasin-B (CB), an inhibitor of insulin-sensitive glucose transporters. RESULTS: Ischemic injury, as assessed by creatine kinase (CK) release was diminished by an average of 50% in HG, NIA, and CAR hearts, and the percentage recovery of left ventricular (LV) function with reperfusion was enhanced by approximately 20% compared with CON hearts (P < 0.05 for each comparison). Cytochalasin-B abolished all of the salutary effects. Long-chain acyl carnitines levels were higher in HG hearts compared with NIA- and CAR-treated hearts ( P < 0.05), but ischemic protection and functional recovery was greater in HG hearts. CONCLUSIONS: The data support the adjunctive use of agents that promote glucose uptake during ischemia and suggest that increasing glucose use is more important than decreasing LCAC in the protection against ischemic injury or in the recovery of contractile function.  相似文献   
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The objective of the study was to determine the degree of linear growth retardation of patients with vitamin D deficiency rickets at presentation and the magnitude of catch-up growth in relation to their calcium (Ca) homeostasis and hormones affecting it before and after treatment. This prospective study recorded the anthropometric data and measured the circulating 25-hydroxy vitamin D (25-OH-D), insulin-like growth factor I (IGF-I), parathyroid hormone, Ca, phosphate, and alkaline phosphatase concentrations in 46 infants and children with nutritional (vitamin D deficiency) rickets before and 6 months or more after treatment with one intramuscular injection of vitamin D3 megadose (300000 IU). Forty normal age- and sex-matched children were included as controls for the auxological data. At presentation, patients' mean age = 13.1 +/- 1.1 months, length standard deviation scores (LSDS) = -1.5 +/- 0.2, and body mass index = 16.3 +/- 0.85. They were significantly shorter and had markedly lower growth velocity standard deviation scores (GVSDS) compared with normal controls (LSDS = 0.25 +/- 0.18 and 0.31 +/- 0.22, respectively). Six months after treatment, the LSDS increased significantly in patients to -0.45 +/- 0.13, with a significantly increased GVSDS (2.76 +/- 0.45) and body mass index (16.9 +/- 0.65). They were still shorter but with significantly higher GVSDS compared with normal controls. Serum Ca and phosphate concentrations increased from 2.07 +/- 0.25 and 1.23 +/- 0.24 mmol/L, respectively, before treatment to 2.44 +/- 0.2 and 1.94 +/- 0.2 mmol/L, respectively, after treatment. Serum alkaline phosphatase and parathyroid hormone concentrations decreased from 1183 +/- 219 U/L and 294 +/- 87 pg/mL, respectively, before treatment to 334 +/- 75 U/L and 35.2 +/- 15.2 pg/mL, respectively, after treatment. The 25-OH-D level increased from 4.5 +/- 0.56 ng/mL before treatment to 44.5 +/- 3.7 ng/mL after treatment. Circulating concentrations of IGF-I increased significantly after treatment (52.2 +/- 18.9 ng/mL) vs before treatment (26.6 +/- 12.8 ng/mL). The 25-OH-D concentrations were correlated significantly with the IGF-I levels before and after treatment (r = 0.603 and r = 0.59, respectively; P < .001). The GVSDS after treatment was correlated with the increase of IGF-I and 25-OH-D levels (r = 0.325 and r= 0.314, respectively; P < .01). These data denote that the accelerated linear growth after treatment of nutritional vitamin D deficiency is mediated through activation of the growth hormone/IGF-I system and suggests an important role of vitamin D as a link between the proliferating cartilage cells of the growth plate and growth hormone/IGF-I secretion. Three different sequential stages of vitamin D deficiency can be recognized according to the clinical/radiological, biochemical, and hormonal data of patients at presentation.  相似文献   
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Background and objectives

Masked hypertension and elevated nighttime BP are associated with increased risk of hypertensive target organ damage and adverse cardiovascular and renal outcomes in patients with normal kidney function. The significance of masked hypertension for these risks in patients with CKD is less well defined. The objective of this study was to evaluate the association between masked hypertension and kidney function and markers of cardiovascular target organ damage, and to determine whether this relationship was consistent among those with and without elevated nighttime BP.

Design, setting, participants, & measurements

This was a cross-sectional study. We performed 24-hour ambulatory BP in 1492 men and women with CKD enrolled in the Chronic Renal Insufficiency Cohort Study. We categorized participants into controlled BP, white-coat, masked, and sustained hypertension on the basis of clinic and 24-hour ambulatory BP. We obtained echocardiograms and measured pulse wave velocity in 1278 and 1394 participants, respectively.

Results

The percentages of participants with controlled BP, white-coat, masked, and sustained hypertension were 49.3%, 4.1%, 27.8%, and 18.8%, respectively. Compared with controlled BP, masked hypertension independently associated with low eGFR (−3.2 ml/min per 1.73 m2; 95% confidence interval, −5.5 to −0.9), higher proteinuria (+0.9 unit higher in log2 urine protein; 95% confidence interval, 0.7 to 1.1), and higher left ventricular mass index (+2.52 g/m2.7; 95% confidence interval, 0.9 to 4.1), and pulse wave velocity (+0.92 m/s; 95% confidence interval, 0.5 to 1.3). Participants with masked hypertension had lower eGFR only in the presence of elevated nighttime BP (−3.6 ml/min per 1.73 m2; 95% confidence interval, −6.1 to −1.1; versus −1.4 ml/min per 1.73 m2; 95% confidence interval, −6.9 to 4.0, among those with nighttime BP <120/70 mmHg; P value for interaction with nighttime systolic BP 0.002).

Conclusions

Masked hypertension is common in patients with CKD and associated with lower eGFR, proteinuria, and cardiovascular target organ damage. In patients with CKD, ambulatory BP characterizes the relationship between BP and target organ damage better than BP measured in the clinic alone.  相似文献   
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