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91.
[Purpose] The purpose of this study was to assess the possible role of physical activities, calcium consumption and lifestyle factors in both bone mineral density and bone metabolism indices in 350 young adult volunteers. [Subjects and Methods] All volunteers were recruited for the assessment of lifestyle behaviors and physical activity traits using validated questioners, and bone mineral density (BMD), serum osteocalcin (s-OC), bone-specific alkaline phosphatase (BAP), and calcium were estimated using dual-energy X-ray absorptiometry analysis, and immunoassay techniques. [Results] Male participants showed a significant increase in BMD along with an increase in bone metabolism markers compared with females in all groups. However, younger subjects showed a significant increase in BMD, OC, BAP, and calcium compared with older subjects. Osteoporosis was more common in older subjects linked with abnormal body mass index and waist circumference. Bone metabolism markers correlated positively with BMD, physically activity and negatively with osteoporosis in all stages. Also, moderate to higher calcium and milk intake correlated positively with higher BMD. However, low calcium and milk intake along with higher caffeine, and carbonated beverage consumption, and heavy cigarette smoking showed a negative effect on the status of bone mineral density. Stepwise regression analysis showed that life style factors including physical activity and demographic parameters explained around 58–69.8% of the bone mineral density variation in young adults especially females. [Conclusion] body mass index, physical activity, low calcium consumption, and abnormal lifestyle have role in bone mineral density and prognosis of osteoporosis in young adults.Key words: Bone mineral density (BMD), Lifestyle, Physical activity  相似文献   
92.
93.

OBJECTIVE:

To evaluate the horizontal mattress technique in microvascular anastomosis for size-mismatched vessels.

METHODS:

The present study involved cadaveric simulation using size-mismatched (1.5:1) Thiel-embalmed cadaveric arteries. The authors performed horizontal mattress anastomoses using 9-0 nylon suture and recorded the procedure. Vessel patency was evaluated by saline infusion. Vessels were cut open and photographed; histological slides were prepared and stained with hematoxylin and eosin.

RESULTS:

Four anastomoses were performed. Vessels were found to be patent in all cases, with grade 0 leaks. Intima-on-intima apposition with no intraluminal exposure of muscularis nor adventitia were observed.

CONCLUSION:

The present cadaveric study supports the technical feasibility of using horizontal mattress sutures in size-mismatched end-toend anastomoses.  相似文献   
94.

Objective:

To explore the outcomes of a pilot intervention of a type 2 diabetes (T2D) education program, based on international standards, and adapted to the cultural and religious contexts of Saudi women.

Methods:

This study is an experiment of a pilot intervention carried out between August 2011 and January 2012 at the primary health clinics in Dammam. Women at risk of or diagnosed with T2D (N=35 including dropouts) were assigned to one of 2 groups; an intervention group participated in a pilot intervention of T2D education program, based on international standards and tailored to their cultural and religious contexts; and a usual care group received the usual care for diabetes in Saudi Arabia. Outcomes included blood glucose, body composition, 6-minute walk distance, life satisfaction, quality of life, and diabetes knowledge. The intervention group participated in a focus group of their program experience. Data analysis was based on mixed methods.

Results:

Based on 95% confidence interval comparisons, improvements were noted in blood sugar, 6-minute walk distance, quality of life, and diabetes knowledge in participants of the intervention group. They also reported improvements in lifestyle-related health behaviors after the education program.

Conclusion:

Saudi women may benefit from a T2D education program based on international standards and adapted to their cultural and religious contexts.Saudi women have a higher prevalence of obesity than men, which increases their risk of type 2 diabetes (T2D).1 The reporting of diabetes is higher in women compared to men in all provinces of Saudi Arabia.1 Diabetes education programs in Saudi Arabia do not target people at risk of diabetes with emphasis on diabetes prevention and feasible changes to lifestyle behaviors.2 Scientific evidence suggests that diabetes education programs based on international standards of lifestyle behaviors, are more effective when tailored to the cultures and religions of targeted groups.3-6 The aim of this study was to explore the outcomes of a pilot intervention of a T2D education program based on international standards and adapted to the cultural and religious contexts of Saudi women. Specifically, whether such a program can impact health outcomes (for example, physical health measures, diabetes knowledge, life satisfaction, and health-related quality of life, diabetes knowledge) in comparison with the usual care of T2D in Saudi Arabia.  相似文献   
95.
Physical activity (PA) and exercise is known to have a positive impact on a variety of variables pertinent to diabetes and cardiovascular disease. The aims of this study were to investigate the effects of physical activity on fatigue scores, oxidative stress, and glycemic control variables of individuals with type 2 diabetes mellitus (T2DM). Seventy-five subjects diagnosed with T2DM for more than 5 years aged 18–65 years participated in this study. The participants classified according to energy expenditure into, physically inactive [≤500 metabolic equivalents (METs)-min/week, n?=?25], moderate PA (500–2500 METs-min/week, n?=?25), and PA (≥2500 METs-min/week, n?=?25). The Global Physical Activity Questionnaire (GPAQ) version 2.0 was used to classify physical activity. The multidimensional checklist individual strength questionnaire (CIS20r) was used to measure chronic fatigue. Blood glucose was measured using a glucose oxidase and peroxidase (GOD-POD) colorimetric method. HbA1c was measured using a commercial kit. Serum insulin level was determined using an ELISA. Analysis of oxidative stress parameters including malonaldehyde (MDA) and total antioxidant capacity (TAC) was done. To test differences between severely fatigued and healthy subjects, an independent t test was performed. Spearman correlations were used to assess correlations between fatigue severity score and disease-related and psychosocial factors. A level of significance was set at p?<?0.05. The results showed a significant reduction of fasting blood sugar, glycosylated hemoglobin, fasting insulin, and MDA along with significant increase in TAC activity in the participants with moderate PA (P?<?0.05) and PA (P?<?0.01), respectively. In relation to CIS-fatigue measurements, about 33 % of the study population (n?=?25) had a CIS score above the cutoff score of 37 with 59.5 mean CIS score, and 67 % of the study population (n?=?50) had CIS score below the cutoff 37; they were classified into heightened fatigue (score 27–35) and healthy (score ≤27). There was a significant correlation between the reduction of diabetic related variables, BMI, PA status, and CIS-fatigue score analyses in T2DM patients. CIS-fatigue scores correlated positively with diabetic related variables and negatively with PA, BMI, and TAC activity. PA plays a vital role in improving CIS-fatigue score in type 2 diabetic patients via reducing oxidative stress and diabetic related variables.  相似文献   
96.

Purpose

This study aimed at comparing the development of tricuspid and mitral regurgitation between the right ventricular outflow tract (RVOT) and right ventricular apex (RVA) pacing.

Methods

We prospectively enrolled 164 patients for permanent pacemaker implantation due to sick sinus syndrome or atrioventricular block and randomly divided them into two equal groups to receive either RVOT or RVA pacing. Patients with heart failure or valvular disease were excluded. The post-procedural echocardiographic evaluations were performed 1 year after the pre-procedural echocardiography, and the results were compared with respect to the development of mitral and tricuspid regurgitation and probable changes in the ejection fraction (EF).

Results

Age, gender, pacing mode, and baseline cardiac rhythm did not significantly differ between the RVOT and RVA pacing groups. The incidence of mitral regurgitation was significantly higher in the RVA group (p?=?0.03), but the incidence of tricuspid regurgitation was similar in both groups. There was a trend toward less tricuspid regurgitation in the RVOT group; however, it was not statistically significant. The mean EF was not significantly different between the study groups.

Conclusion

It seems that the incidence of mitral regurgitation in RVA pacing is significantly higher than that in RVOT pacing. The formation of tricuspid regurgitation needs to be discussed in the future.

Clinical trial registration number

IRCT201103146061N1  相似文献   
97.
A protocol for the efficient synthesis of arylbenzodioxy xanthenedione scaffolds was developed via a one-pot multi-component reaction of aromatic aldehydes, 2-hydroxy-1,4-naphthoquinone, and 3,4-methylenedioxy phenol using mesoporous PbO nanoparticles (NPs) as a catalyst under ball milling conditions. The synthesis protocol offers outstanding advantages, including short reaction time (60 min), excellent yields of the products (92–97%), solvent-free conditions, use of mild and reusable PbO NPs as a catalyst, simple purification of the products by recrystallization, and finally, the use of a green process of dry ball milling.

An efficient one-pot multicomponent protocol was developed for the synthesis of arylbenzodioxy xanthenedione scaffolds using mesoporous PbO nanoparticles as reusable catalyst under solvent-free ball milling conditions.

Recently, the ball milling technique has received great attention as an environmentally benign strategy in the context of green organic synthesis.1a The process of “ball milling” has been developed by adding mechanical grinding to the mixer or shaker mills. The ball milling generates a mechanochemical energy, which promotes the rupture and formation of the chemical bonds in organic transformations.1b Subsequently, detailed literature1c and books on this novel matter have been published.2a,b Several typical examples include carbon–carbon and carbon–heteroatom bond formation,2c organocatalytic reactions,2d oxidation by using solid oxidants,2e dehydrogenative coupling, asymmetric, and peptide or polymeric material synthesis, which have been reported under ball milling conditions.2e Hence, the organic reactions using ball milling activation carried out under neat reaction environments, exhibit major advantages,2f including short reaction time, lower energy consumption, quantitatively high yields and superior safety with the prospective for more improvement than the additional solvent-free conditions and clear-cut work-up.3–5On the other hand, the organic transformations using metal and metal oxide nanoparticles6 are attracting enormous interest due to the unique and interesting properties of the NPs.7,8,9a Particularly, PbO NPs9b provide higher selectivity in some organic reactions9c and find applications in various organic reactions, like Paal–Knorr reaction,10 synthesis of diethyl carbonate,11 phthalazinediones,12 disproportionation of methyl phenyl carbonate to synthesize diphenyl carbonate,13 the capping agent in organic synthesis, and selective conversion of methanol to propylene.14 In addition, the PbO NPs are also used in many industrial materials.15,16However, till date, PbO NPs have not been explored in MCRs leading to biologically important scaffolds. Among others, the xanthene scaffolds17 are one of the important heterocyclic compounds18 and are extensively used as dyes, fluorescent ingredients for visual imaging of the bio-molecules, and in optical device technology because of their valuable chemical properties.19 The xanthene molecules have conjointly been expressed for their antibacterial activity,20 photodynamic medical care, anti-inflammatory drug impact, and antiviral activity. Because of their various applications, the synthesis of these compounds has received a great deal of attention.21 Similarly, vitamin K nucleus22,23 shows a broad spectrum of biological properties, like anti-inflammatory, antiviral, antiproliferative, antifungal, antibiotic, and antipyretic.24a As a consequence, a variety of strategies24b have been demonstrated in the literature for the synthesis of xanthenes and their keto derivatives, like rhodomyrtosone-B,25a rhodomyrtosone-I,25b and BF-6 25c as well as their connected bioactive moieties. Few biologically active xanthene scaffolds are shown in (Fig. 1).Open in a separate windowFig. 1Some biologically important xanthenes and their keto derivatives.Due to the significance of these compounds, the synthesis of xanthenes and their keto derivatives using green protocols is highly desirable. Reported studies reveal that these scaffolds are synthesized by three-component condensations using p-TSA26 and scolecite27 as catalysts. However, these methods suffer from the use of toxic acidic catalysts like p-TSA, long reaction times (3 h), harsh refluxing26 or microwave reaction conditions,27 and tedious work-up procedures. The previously reported methods for the synthesis of xanthenediones are shown in Scheme 1.Open in a separate windowScheme 1Previous protocol for the synthesis of xanthenedione derivatives.Herein, we report an economical and facile multicomponent protocol, using ball milling, for the synthesis of 7-aryl-6H-benzo[H][1,3]dioxolo[4,5-b]xanthene-5,6(7H)-dione using PbO NPs as a heterogeneous catalyst (Scheme 2). The PbO NPs are non-corrosive, inexpensive, and easily accessible.Open in a separate windowScheme 2General reaction scheme of PbO NP-catalyzed synthesis of the xanthenedione scaffolds under ball milling conditions.In our protocol,28 the PbO NPs were initially prepared by mixing sodium dodecyl sulphate (2.5 mmol) and sodium hydroxide (10 mL, 0.1 N) with an aqueous methanolic solution of lead nitrate (2 mmol) under magnetic stirring at 30 °C by continuing the reaction for 2 h. Then, the obtained white polycrystalline product was filtered, washed with H2O, and dried at 120 °C, followed by calcination at 650 °C for 2 h. During this step, the white PbO NPs turned pale yellow in colour. Eventually, the synthesized PbO was then characterized by spectroscopic and analytical techniques.The powder X-ray diffraction (XRD) pattern revealed the crystalline nature of the PbO NPs as the diffraction peaks corresponding to (131), (311), (222), (022), (210), (200), (002), and (111) crystal planes were identified (Fig. 2). The XRD outline of the synthesized PbO NPs was further established for the formation of space group Pca2129 with a single orthorhombic structure (JCPDS card number 76-1796). The sharp diffraction peaks indicated good crystallinity, and the average particle size of the PbO NPs was estimated to be 69 nm, as calculated using the Debye–Scherer equation.Open in a separate windowFig. 2The powder XRD pattern of PbO NPs.The surface morphology of the PbO NPs was analyzed by scanning electron microscopy (SEM), and the SEM image revealed the discrete and spongy appearance of the PbO NPs (Fig. 3).Open in a separate windowFig. 3The SEM image of PbO NPs.Moreover, the elemental composition obtained from energy dispersive X-ray (EDX) analysis confirmed that the material contains Pb and O elements, and no other impurity was present (Fig. 4).Open in a separate windowFig. 4The EDAX spectrum of crystalline PbO NPs.The transmission electron microscopy (TEM) image shown in Fig. 5 indicated the formation of orthorhombic crystallites of PbO with several hexagon-shaped particles. The dark spot in the TEM micrograph further confirmed the synthesis of PbO NPs, as the selected area diffraction pattern associated with such spots reveals the occurrence of the PbO NPs in total agreement with the X-ray diffraction data (Fig. 6). The average size of the PbO nanocrystals by TEM was approximated to be around 20 nm.Open in a separate windowFig. 5The TEM image of nanocrystalline PbO NPs.Open in a separate windowFig. 6The SAED image of nanocrystalline PbO NPs.The Fourier transform infrared (FT-IR) spectrum (ESI, S6) of the PbO NPs displayed peaks at 575, 641, and 848 cm−1, which corresponds to the Pb–O vibrations. Furthermore, the absorption band at ∼3315 cm−1 was due to the presence of the hydroxyl group (–OH) in the NPs.The N2 adsorption–desorption isotherms of the PbO nanoparticles shown in Fig. 7 was consistent with type IV adsorption–desorption isotherms with H1 hysteresis corresponding to the cylindrical mesoporous structure. Moreover, the surface area, pore-volume, and BJH pore diameter were found to be 32.0 m2 g−1, 0.023 cm3 g−1, and 30.9 Å, respectively.Open in a separate windowFig. 7BET surface area and pore size of nanocrystalline PbO catalyst.The catalytic activity of the synthesized PbO NPs was tested in a one-pot multicomponent synthesis of arylbenzodioxoloyl xanthenedione derivative under ball milling condition according to the reaction scheme 2a, with 3,4-dimethoxybenzaldehyde (166.2 mg, 1.0 mmol), 3,4-methylenedioxyphenol (138.0 mg, 1.0 mmol), and 2-hydroxy-1,4-naphthoquinone (174.0 mg, 1.0 mmol) as reactants. The reaction conditions, the ball milling parameters (speed, time, and ball to solids ratio), and the PbO nanocatalyst amount were first optimized to produce the highest yield using experimental design as shown in
EntryConditionsRotation (rpm)Catalyst (mol%)Time (min)Yield (%)a
1Ball milling400005021
2Ball milling400105048
3Ball milling400156054
4Ball milling400207059
5Ball milling500105062
6Ball milling500155065
7Ball milling500206067
8Ball milling600107071
9Ball milling600155077
10Ball milling600206082
11Ball milling600057090
12Ball milling600105091
13 Ball milling b 600 15 60 97
14Ball milling600207097
15No ball millingc1560
Open in a separate windowaIsolated yield; model reaction: 3,4-dimethoxybenzaldehyde (166.2 mg, 1.0 mmol), 3,4-methylenedioxyphenol (138.1 mg, 1.0 mmol), 2-hydroxy-1,4-naphthoquinone (174.1 mg, 1.0 mmol) under ball milling.bOptimized reaction conditions.cThe reaction was performed under stirring condition in a RB flask.Next, by utilizing the general experimental procedure (ESI for detail experimental procedure; S2) and the aforementioned optimized conditions (29 we also investigated the possible scopes of the reactants as revealed in 26 These data are available in S4 (see ESI for the spectroscopic data). The aromatic aldehydes comprising both electron-withdrawing (e.g., nitro group) and electron-donating (e.g., –OMe, –OH, –Cl, –Me, and –Br) groups participated proficiently in the reaction without including any electronic effects. The aromatic aldehyde with electron-donating groups (e.g., –OMe, –OH, –Cl, –Me, and –Br) increased the product yield, while in the case of aryl aldehyde having an electron-withdrawing group (e.g., –NO2), both the product yield as well as the reaction rate decreased. These findings are depicted in Scope of the PbO NP-catalyzed synthesis of arylbenzodioxoloyl xanthenedione derivatives
Open in a separate windowFollowing a previously reported mechanism,26 a possible mechanism for the synthesis of arylbenzodioxoloyl xanthenedione derivative under ball milling at 600 rpm for 60 min is shown in Scheme 3. It is speculated that in the first step, the surface of the PbO NPs having free –O–H groups facilitated the carbon–carbon bond formation by activating aromatic aldehyde 1a to react with 2-hydroxy-1,4-naphthoquinone 1b leading to the intermediate B, which further undergoes dehydration, followed by the addition of 3,4-methylenedioxyphenol 1c, which upon cyclization leads to the formation of the product 2a with the recovery of the catalyst, PbO NPs.Open in a separate windowScheme 3Plausible mechanism of PbO NP-catalyzed synthesis of arylbenzodioxoloyl xanthenedione (2a).Further, to signify the advantages of the current methodology, a comparative study of known methods is provided in Sr. no.CatalystReaction conditionsYield (%)Time (min)Reusable?1 p-TSA26EtOH/90–120 °C85–90180No2Scolecites27EtOH/80 oC90–924–15 MWYes up to 3 cycles3 aPbO NPsAmbient temperature92–9760Yes up to 8 cyclesOpen in a separate windowaPresent work.Next, we investigated the reusability of the PbO nanocatalyst for the synthesis of 7-(3,4-dimethoxyphenyl)-6H-benzo[H][1,3]dioxolo[4,5-b]xanthene-5,6(7H)-dione (2a) as a model reaction. After the reaction, PbO NPs were separated from the reaction mixture by centrifugation, washed consecutively with aqueous ethanol, dried, and reused for the next run. As shown in Fig. 8, the reaction yield was reduced by only 12% after eight consecutive runs. This slight decrease in the yield was observed due to the loss of PbO NPs (∼10 wt%) during the recycling process.Open in a separate windowFig. 8Reusability of PbO NPs for the synthesis of 7-(3,4-dimethoxyphenyl)-6H-benzo[H][1,3]dioxolo[4,5-b]xanthenes-5,6 (7H)-dione as a model reaction.The fate of the recycled PbO NPs was analyzed by performing SEM and TEM studies after the 8th run, and considerable agglomeration of NPs was observed. However, interestingly the particle size of the NPs reduced to ∼15 nm compared to fresh PbO NPs during the ball milling process (Fig. 9).Open in a separate windowFig. 9(a) SEM and (b) TEM images of the recycled PbO NPs after 8th run.In conclusion, we demonstrated a facile and efficient method for the synthesis of 7-aryl-6H-benzo[H][1,3]dioxolo[4,5-b]xanthene-5,6(7H)-dione using PbO NPs as a catalyst. The entire synthesis process was very clean and provided very high yields (86–97%) of xanthenedione derivatives (2a–l) via mild ball milling. Moreover, the present protocol has demonstrated significant development in terms of higher isolated yields, faster rate of reaction (1 h), and most importantly, it is environment-friendly. Moreover, the use of solvent-free ball milling conditions allows simple isolation and purification of the products, with no column chromatography, as well as the mild PbO NPs as a reusable catalyst made the current synthetic method more suitable and environmentally benign in nature.  相似文献   
98.
B-lymphoblastic leukemia/lymphoma: overexpression of nuclear DNA repair protein PARP-1 correlates with antiapoptotic protein Bcl-2 and complex chromosomal abnormalities     
Payam Pournazari  Ruth F. Padmore  Farid Kosari  Peter Scalia  Meer-Taher Shahbani-Rad  Sami Shariff  Douglas J. Demetrick  Mark Bosch  Adnan Mansoor 《Human pathology》2014
  相似文献   
99.
Validation of the AASLD recommendations for classification of oesophageal varices in clinical practice     
Waleed Fateen  Krish Ragunath  Jonathan White  Amardeep Khanna  Marina Coletta  Sunil Samuel  Jacobo Ortiz  Martin James  Emilie Wilkes  Guruprasad P. Aithal  Indra N. Guha  Sarmed S. Sami 《Liver international》2020,40(4):905-912
  相似文献   
100.
Enhancing and neutralizing anti‐coxsackievirus activities in serum samples from patients prior to development of type 1 diabetes     
Famara Sane  Antoine Bertin  Amir‐Babak Sioofy‐Khojine  Sami Oikarinen  Enagnon K. Alidjinou  Riitta Veijola  Jorma Toppari  Jorma Ilonen  Mikael Knip  Ilka Engelmann  Heikki Hyty  Didier Hober 《Diabetes/metabolism research and reviews》2020,36(6)
  相似文献   
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