Fit statistics suggest both good fitting and prediction. Water absorption, hydrolytic degradation and contact angle were mediated by the hydrophilic nature of the polyols. Tensile strength, modulus and hardness could be regulated by the PE content and the characteristics of polyols. Regression of DTG curves from thermal analysis showed improvement of thermal stability with the increase of PCL and PE. An ANOVA test of the model terms demonstrated that three component influences on bulk properties like water absorption, hydrolytic degradation, hardness, tensile strength and modulus. The PEG*PCL interaction influences on the contact angle, which is a surface property. Mixture design application allowed for an understanding of the structure-property relationship through mathematic models.Polyurethanes are materials with a strong structure-property relationship. The goal of this research was to study the effect of a polyol blend composition of polyurethanes on its properties using a mixture design and setting mathematic models for each property. Water absorption, hydrolytic degradation, contact angle, tensile strength hardness and modulus were studied. Additionally, thermal stability was studied by thermogravimetric analysis. Area under the curve was used to evaluate the effect of polyol blend composition on thermal stability and kinetics of water absorption and hydrolytic degradation. Least squares were used to calculate the regression coefficients. Models for the properties were significant, and lack of fit was not ( Polyurethanes (PUs) are a special group of polymers with a wide range of applications in industry, including adhesives, aircraft, furniture, insulation, construction and biomedical applications. Their versatility is explained by the variety of properties expressed by PUs, which are closely related with their composition . The priStudies of polyol composition have been carried out. Trzebiatowska et al. obtained polyurethanes from the glycerolysate of recycled polyurethanes and poly(ethylene-butylene) adipate diol. As the content of the recycled component increased, the swelling ratio decreased, and the crosslink density simultaneously increased, resulting in the rise of glass transition and storage modulus at room temperature. Thermomechanical stability, tensile strength, elastic modulus and hardness of the PUs also increased and elongation at break decreased with the incorporation of glycerolysate. The original polyol used was tri-functional, and as such, it is possible to have more linkages per polyol molecule. Additionally, more networks could be created in this material as its structure is more branched. These properties can result in a reduction in polymer chains movement .M = ~530, 1250 and 2000 Da), cycloaliphatic diisocyanate 4,4′-methylenebis (cyclohexyl isocyanate) and ethylene glycol as a chain extender. Changes in the macromolecule order, with increasing hard segment content, were observed via modulated differential scanning calorimetry. Depending on the hard segment content, gradual variations in the polyurethane surface properties were observed. Furthermore, as the content of the hard segments increased, the polyurethane surface exhibited more phase separation, a higher content of urethane moieties and higher hydrophilicity [Bil et al. worked with aliphatic poly(ester-urethanes) from poly(ε-caprolactone) diol having different molecular masses  due to hydrolysable bonds like ester bonds, and high level of cell viability (>90%). Additionally, arginine had lower values of release at pH 7.4 as a chain extender, which resulted in less toxicity while fulfilling the requirements. However, at lower pH, behavior change due to the presence of free amino groups in arginine, which were protonated in the presence of acidic conditions, resulted in greater swelling and solvent penetration, thus increasing drug release . Most of those works reported valuable knowledge about the effects of polyols and chain extenders. However, most qualitatively described the interactions between the components of the PUs based on the performance of some properties or, in some cases, just analyzed the behavior of one parameter. To establish the impact of these interactions quantitatively, design of experiment can be used. Design of experiment is a well stablished concept for the planning and execution of informative experiments . Experim2 as a blowing agent. They studied the influences of saturation pressure, temperature and soaking time and their interactions on foaming behavior through a response surface methodology based on the Box-Behnken design. This showed that saturation temperature was the most significant parameter affecting the expansion ratio, shrinkage ratio, and cell morphology of PUs foams. There was an interaction effect between saturation temperature and soaking time, wherein the expansion ratio of the foams was more sensitive to changes in soaking time at higher temperatures. As the soaking time increased, the shrinkage of PUs foams increased first and then leveled off, and the cell diameter decreased significantly [Specifically, in the polyurethanes field, Li et al. examined bio-based flexible polyurethane foams using bio-polyol, extracted from the fast pyrolysis oil of wheat straw, foaming processes such as the bio-polyol to petroleum-based polyol ratio, the polymethylene polyphenylene isocyanate to polymeric diphenyl-methane diisocyanate ratio, and the crosslinking agent content was optimized using response surface methodology. Resilience was found to increase with an increasing amount of petroleum-based polyol, while for bio-polyol, resilience was decreased up to a medium dosage after which there was a slight increase. However, increasing the amount of polymethylene polyphenylene isocyanate along with the petroleum-based polyol had a positive influence on the resilience of PUs, though it declined at a high dosage of polymethylene polyphenylene isocyanate . Zhao etficantly .Despite interest in understanding the structure-property relationship of polyurethanes, to the best of our knowledge there are no reports regarding the application of design of experiments to evaluate the influence of monomer composition on properties of polyurethanes. Thus, the goal of this research is to evaluate the effect of polyol bled composition on the properties of polyurethanes, including water absorption, hydrolytic degradation, contact angle, tensile strength and modulus, through mixture design and data regression, generating mathematic models to better understand the structure-property relationship in PUs. In this work, effect of polyol composition and crosslinker concentration was evaluated on different properties like: thermal behavior, hydrophilicity and hydrolytic degradation and mechanical behavior based on tensile test and hardness. Polyethylene glycol (PEG) and polycaprolactone diol (PCL) were used as polyols whereas pentaerythritol (PE) as crosslinker. Different concentration of those were studied. From this point, polyol blend should be understood as the combination of PEG, PCL and PE. PUs were synthetized by two steps polymerization: first, each polyol blend, with the composition described by the mixture design, was mixed with the IPDI and allowed to react. Further, a solution of crosslinker was add. Finally, bubbles were removed and poured into a cylindrical glass mold.−1, we observed the overtone related with the stretching of N-H bound from urethane and, near 1550 cm−1, the original signal. The asymmetric and symmetric vibration signals of -CH2 from the soft segments of the PCL and PEG and PE, from the hard segment, were observed at 2960 and 2870 cm−1. At 1730 cm−1, we can see the characteristic peak of urethane bound related with -C=O stretching. Additionally, between 1300 and 1050 cm−1, there are two peaks related to the asymmetric and symmetric stretching of -C-O-C- group, which is also part of the urethane bond. Finally, below 1050 cm−1, there are peaks related to the vibration of the aliphatic ring from the IPDI. According to the above, polyurethanes were obtained with an integration of polyols, crosslinker and isocyanate structures. Despite the successful synthesis of PUs, NCO groups vibration was observed around 2250 cm−1 in some PUs due to some NCO groups that didn’t react. Successful of polyurethane synthesis was evaluated by FTIR (Fourier transform infrared spectroscopy). In this work, we applied a mixture design to study the influence of polyol blend composition on properties of polyurethanes. It had 9 design points, PUs with different polyol blend composition, and seven repetitions of some design points. Mixture design used different point types to evaluate the experimental space. This mixture design could be divided into three series: the first series  includes PUs with PCL as the major component named S1, S2, S3, S4, S5. The second lays in the middle of the experimental space . Finally, the opposite extreme where PEG was the major component  was tested.p-value < 0.05) for the properties studied. In addition, lack of fit was not significant at a 95% probability level  in all cases. Both, the model sum of square and lack of fit indicated that the models were adequate. Likewise, fit statistics confirmed good fitting for all properties. According with Olivato et al. an R-square value higher than 0.7 suggests a good fit with the experimental data [Reponses were analyzed by Box-Cox distribution. Transformations were carried out according with Box-Cox suggestions. Therefore, the inverse square root of water absorption and the square root of hydrolytic degradation and tensile strength were applied. Non-transformations were made on contact angle, modulus, hardness, kinetics of water absorption and hydrolytic degradation, and thermal responses. Additionally, DFFITS tests were applied to identify influential points. For contact angle, 2 influential points were deleted from the analysis (S15 and S16). The responses of S11 and S7 were removed for the kinetics of water absorption and thermal response, respectively Special cubic models were fit for each response for the regression models. Model regression based on the least square was used to compute the coefficients. The equations are presented in tal data . In thisTo evaluate the hydrophilicity, water absorption and water contact angle were evaluated. Likewise, an increase in the PE fraction involved a reduction in swelling. PE added to the hard segment and increased the crosslinking of the chains, causing a reduction on chains mobility . As obseChecking the ANOVA results see , the triContact angle measures the affinity between the solvent and material surface. Here, water was used as a solvent; therefore, wettability was evaluated. Lower angles indicate enhanced wettability. The surface is considered hydrophobic when contact angles are over 90° . In FiguHydrolytic degradation occurred after swelling. Water enters the PU matrix. Chain scission takes place through hydrolysis, in which water molecules may facilitate the cleavage of some bonds such as urethane and esters . As mentTime vs. water absorption and hydrolytic degradation studies . Curves were normalized with respect to initial sample weight. First derivate was calculated for each sample. By other hand, As for the onset temperatures , PUs werTo study the effect of composition, regression of onset temperatures was carried out. However, poor fitting properties were obtained (R-square = 0.64). So, the absolute normalized area under the curve (nAUC) of the DTG curves were fitted as approach to index the thermal stability in terms of polyol composition. Ternary plot C showed The mechanical performance of PUs can be regulated by hard segment content or polyol characteristics, such as molecular weight and hydroxyl index. In Additionally, model regression ANOVA showed a significant triple interaction , suggestHardness of the PUs was evaluated too. An increase of PE concentration results in a rise of hardness and largest values was reached at a high concentration of PCL C. ANOVA Regression of elongation at break was carried out, but it showed low fitting properties (R-square = 0.35). This property was not analyzed in this work. Our models were validated by the check point method. Composition of check materials were selected because they were in the experimental space and were different than design points. The response of check materials in properties like water absorption, hydrolytic degradation, tensile strength and contact angle was carried out in Design Expert 10 based on the confidence intervals at 95%. The response of the materials adjusts to the model’s responses. It suggests that our models can predict the structure properties relationship of polyurethanes based on the composition of the polyol blend and can be used to navigate the design space and optimize desired properties. N,N-dimethylformamide (DMF) were purshased from Sigma-Aldrich . Polyethylene glycol  was from Merck KGaA , and pentaerythritol (PE) was from Alfa Aesar . For characterization analysis, phosphate buffer saline (PBS) was purshased from VWR . The following reagents were used for PUs synthesis: polycaprolactone diol (PCL) with average molecular weight of Mn~2000, isophorone diisocyanate (IPDI), v/v) ethanol-water solution for 1 h to remove mold released and dried at 80 °C.Polyurethanes were synthetized via a two-step polymerization. PCL and PEG were used as polyols, PE and IPDI as crosslinkers and as a NCO source, respectively. Each weighed polyol sample was preheated at 110 °C and mixed with 10 mL of DMF, and then IPDI was added keeping the NCO/OH ratio of 1 and allowed to react for 15 min at 70 °C with agitation. In parallel, PE was diluted in 10 mL of DMF at 110 °C with agitation. Next, the PE solution was added to the prepolymer. A vacuum was applied to remove air. Finally, each polymer was poured in cylindrical molds of 100 mm of diameter and 2 to 3 mm of height and cured at 110 °C for 12 h. After the curing period, PUs were washed in a 50% . The experiment was setup in 32 scans and resolution of 4. The chemical structure of the PUs was evaluated by Fourier-transform infrared spectroscopy (FTIR) over a range of 400 cmThermal behavior was studied by thermogravimetric assay in a TGA/DSC 1 . The method consisted of two steps. The first was at 105 °C for 1 h to remove water and solvent traces. The second a dynamic heating from 105 to 600 °C at a rate of 10 °C/min. Tests were carried out under nitrogen atmosphere with a flow of 180 mL/min. Curve were normalized respect to initial weight of the sample. DTGs, onset temperatures and normalized area under de curve were calculated using the STARe software provided by the TGA/DSC1 supplier. Contact angle was determined using a MobileDrop  with distilled water at room temperature and the sessile drop method. At least 3 measurements per polymer were taken, and the average of those was reported. Water absorption was evaluated by soaking each sample in triplicate in 1 mL of PBS 1× Samples were incubated for 48 h at 37 °C. Swelling was calculated with the initial weight (Wo) and the final weight (Ws), according with the following equation:Hydrolytic degradation was analyzed by soaking the samples in PBS 1x as before. After 48 h, samples were dried in an oven at 80 °C until a constant weight was reached. The dried weight was recorded (Wi), and degradation was calculated as follows:Kinetics of water absorption and hydrolytic degradation were carried out, following the method described for each property. At least 5 time points were recorded in interval of 120 h. Curve were analyzed based on the %Water absorption and %Degradation. Under the curve area was calculated using the trapezoid method. The mechanical properties of PUs were assessed by uniaxial tensile test with EZ-XL universal test machine  at 10 mm/min. Ultimate stress, modulus and elongation at break were recorded. Shore A hardness was measured using a shore A durometer. 10 measurements were recorded for each sample and the average was used for the model regression. Application of a mixture design allowed us to establish mathematic relationships for the effects of polyol blend composition on properties of polyurethane obtained from PEG and PCL (polyol), PE (crosslinker) and IPDI (isocyanate). An ANOVA test and fit statistics suggested a good fit and predictive potential with those equations. Water absorption, hydrolytic degradation and contact angle responses were modulated by the polar nature of polyols and crosslinker concentrations. However, tensile strength, modulus and hardness could be mediated by other characteristics of the polyols such as molecular weight and hydroxyl value, together with the crosslinker concentration. From a statistical perspective, a triple interaction (PEG*PCL*PE) with water absorption, hydrolytic degradation, tensile strength, hardness and modulus was significant, but not for contact angle, where the PEG*PCL interaction was significant. This suggests that bulk properties such as those in the first group are regulated by the three components in the composition, but contact angle, as a surface property, is mediated by the polyol nature. Thermal stability was evaluated by the area under the curve of the DTGs. It shows that increases of PCL and PE improved stability. Additionally, hydrolytic stability was evaluated by the area under the curve from the water absorption and hydrolytic degradation kinetics where similar behavior was observed, showing that the area under the curve could be used to identify the effects of variables. To conclude, this methodology allowed for a better understanding of the structure-property relationship through a mathematic model, identifying the main effects of the polyol blend composition on the final properties. These models look promising for optimization to design a polyurethane with target properties, and the mixture design could be extrapolated to other components such as isocyanate and the NCO/OH ratio.


Background: Dietary interventions in rodents can induce an excess of adipose tissue and metabolic disorders that resemble human obesity. Nevertheless, these approaches are not standardized, and the phenotypes may vary distinctly among studies. The aim of this study was to investigate the effects of different dietary interventions on nutritional, metabolic, biochemical, hormonal, and cardiovascular profiles, as well as to add to development and characterization of an experimental model of obesity. Methods: Male Wistar rats were randomized into four groups: control diet (C), high-sugar (HS), high-fat (HF), or high-sugar and high-fat (HFHS). Weekly measurements of body weight, adiposity, area under the curve (AUC) for glucose, blood pressure (BP) and serum triglycerides, total cholesterol level, and leptin were performed. Results: HF and HFHS models were led to obesity by increases in adipose tissue deposition and the adiposity index. All hypercaloric diets presented systolic BP increases. In addition, the AUC for glucose was greater in HF and HFHS than in C, and only the HF group presented hyperleptinemia. Conclusions: HF and HFHS diet approaches promote obesity and comorbidities, and thus represent a useful tool for studying human obesity-related disorders. By contrast, the HS model did not prove to be a good model of obesity. Obesity is a disease with multiple causes and one which is characterized by increased adipose tissue; it is considered a worldwide epidemic and a serious public health problem ,2. This (ob/ob mouse) or an autosomal recessive mutation in the fatty (fa) gene on chromosome 5 (Zucker-fa/fa–fatty rat) have mainly been used [Animal models are commonly used to mimic human diseases and to improve understanding of the pathophysiology of obesity-related disorders . Rodentseen used . In addieen used . Cao et een used  have demeen used ,12 typiceen used ,13,14. Been used ,15. Thereen used . By conteen used ,15.Another important aspect is that high calorie diets are based on cafeteria diets, which often do not accurately reproduce the population’s food profile . Thus, tThus, the key point regarding which hypercaloric diet type  best characterizes, and as a representative model for the study of human obesity-related disorders, remain unclear. Therefore, this study was designed to investigate the effects of these dietary interventions—excess sugar or lard—or a combination of sugar and lard on metabolic disorders and cardiovascular health with long-term exposure. In addition, the study aimed to add to the development and characterization of a rodent obesity model from different hypercaloric diets to establish an appropriate model that is easily reproducible and mimics characteristics observed in the genesis of this condition in humans.≅110 g) obtained from the Animal Quarters of the Federal University of Espírito Santo  were individually caged and subjected to different dietary regimens. The environment was maintained under a 12 h reversed light/dark cycle that started at 9:00, in a clean-air room at a constant temperature of 23 ± 3 °C and relative humidity of 60% ± 5%. All experiments and procedures were performed in accordance with the Guide for the Care and Use of Laboratory Animals published by the U.S. National Institutes of Health [Thirty-day-old male Wistar rats , high-sugar diet , high-fat diet , and high-fat and high-sugar diet . The duration of the experimental protocol was 20 consecutive weeks, following which the rats were euthanized . The feed ingredients were blended, homogenized, and extruded  in the form of pellets. Then, the pellets were dried on a horizontal conveyor dryer . The composition (g/kg) and nutrients for each experimental diet (%) are described in The experimental diets provided sufficient amounts of protein, vitamins, and minerals according to the Nutrient Requirements for Laboratory Animals . The dieAfter 20 weeks of the experimental protocol, rats were anesthetized intraperitoneally with ketamine hydrochloride  and xylazine hydrochloride . Following this, their chests were opened by mid-thoracotomy, and the adipose tissue fat pads were dissected and weighed. The adiposity index used to assess obesity was calculated using the following formula: adiposity index (body fat (BF)/final body weight) × 100. BF was measured from the sum of the individual fat pad weights as follows: BF = epididymal fat + retroperitoneal fat + visceral fat.® MP100, Biopac Systems, Inc., Santa Barbara, CA, USA). The average of three readings was recorded for each measurement. Records associated with tail movement and/or other stressors that could interfere with the measurement were discarded.After the conclusion of the experiments (before killing), the systolic blood pressure (SBP) was measured in conscious rats using the non-invasive tail-cuff method with an electro-sphygmomanometer . The animals were warmed in a wooden box between 38–40 °C with heat generated by two incandescent lamps for 4 min to cause vasodilation in the tail artery, and rats were then transferred to an iron cylindrical support that was specially designed to allow total exposure of the animal’s tail. After that, a sensor was placed in the proximal region of the tail, coupled to the electro-sphygmomanometer. The arterial pulsations were recorded in a computerized data acquisition system . Subsequently, an injection of glucose solution (2 g/kg body weight) dissolved in water was administered intraperitoneally, and blood glucose levels were measured after 30, 60, 90, and 120 min . Glucose®, Belo Horizonte, Minas Gerais, Brazil and Synermed do Brasil Ltda., São Paulo, Brazil) and analyzed by automated biochemical equipment BS-200 . Leptin and insulin levels were determined using an enzyme-linked immunosorbent assay (ELISA) using specific kits . The reading was carried out using a microplate reader .At the end of the experimental period, the animals were subjected to 12–15 h of fasting, and blood samples were collected in dry tubes. The serum was separated by centrifugation at 10,000 rpm for 10 min.  and stored at −80 °C for subsequent analysis . Serum glucose (GL), triglycerides (TG), total cholesterol (T-Chol), and high-intensity cholesterol (HDL) concentrations were measured using specific kits  and wet weight (WW) ratio was calculated as ((1 – DW)/WW) × 100. In addition, the absolute pancreas weight was also measured.post hoc test. The weekly evolution of body weight and glucose tolerance test were submitted to two-way ANOVA for the repeated measures and complemented by the Tukey post hoc test. The level of significance was 5%.Data from nutritional characteristics, metabolic measurements, and cardiovascular data were reported as mean ± standard error of the mean (SEM) and submitted to the Kolmogorov–Smirnov test to determine adherence to normality. Results obtained from the nutritional characteristics, metabolic measurements, and SBP were analyzed using one-way analysis of variance (ANOVA) followed by the Tukey The evolution of body weight during the 20 weeks of the experimental protocol is displayed in After 20 weeks of the experimental protocol, rats fed with HF gained more body weight (an elevation of 22% and 20.6%) compared to those fed with control and high-sugar diets. There was no difference between C and HS for body weight gain; the same behavior was observed between HF and HFHS rats A. The HFp < 0.05). In addition, there was a difference in FC between rats fed the HF diet compared with the HS group, since rats fed the HS diet consumed significantly less food . Furthermore, HF presented a 12.4% increase in caloric intake over HFHS (p < 0.05). There was no difference in the caloric intake of C compared to HF and HFHS (p > 0.05). While the feed efficiency (%) was higher in the HF (14.3%) and HFHS groups (20.8%) than in C (p < 0.05).Adult male rats fed the C diet for 20 weeks had an approximately 15.2%, 22.8%, and 27.3% greater daily food consumption (g) than the HF, HFHS, and HS groups, respectively, but the daily caloric intake was higher in the HS group in relation to the C and HFHS groups . The other parameters, including glucose, TG, T-Chol, and HDL, were similar among the groups.The comorbidities associated with obesity are summarized in p < 0.05) and were elevated by 25%. Nevertheless, there were no differences in absolute lung and pancreas weights among the groups. Additionally, compared with C animals, there was a statistical reduction in the percentage of water in the liver in the HFHS group. Water percentages of the lungs in all rats were similar among the groups (e groups .This study aimed at the development and characterization of an obesity experimental model in rodents by using dietary interventions of excess sugar, lard, or a combination of lard and sugar, which could induce an excess of adipose tissue and metabolic disorders. The HF and HFHS models share many important features with human obesity, such as increased adiposity, hypertension, glucose intolerance, and hyperleptinemia. However, a high-sugar diet did not cause obesity and metabolic disorders but only hypertension.Experimental models that mimic the eating habits of the population have been widely used to elucidate the mechanisms of obesity and metabolic disorders . In thisThe weekly monitoring of body weight aimed to identify the moment of significant increase in this parameter in animals under the influence of treatments with hypercaloric diets in relation to those treated with a standard diet to effectively evidence the duration of obesity from a given experimental model ,27. In tAccording to the literature, fat-enriched diets have been used for decades to model obesity in rodents . The devThe literature shows that excess fat associated with sugar promotes elevated body weight gain ,39, but The elevation in body weight and adiposity in the hyperlipidic experimental models increased with sugar, refers to caloric intake and food efficiency which, generally, lead to a greater availability of calories and hyperphagia ,43. EvenInterestingly, HS did not lead to an increase in body weight and adipose tissue other than in C. The literature is controversial regarding the experimental obesity models from excessive sugar ,15,16,45Obesity has been associated with several comorbidities, such as glucose intolerance, hyperinsulinemia, insulin resistance, dyslipidemia, and hypertension ,13. The The findings of the present study also demonstrate that only the HL group developed hyperleptinemia, since the animals had 106% more leptin than those of C. However, these animals did not become hyperphagic, thus suggesting that they were not resistant to leptin—a metabolic disorder frequently observed in obesity. According to Knight et al. , in the In addition to changes in glucose and biochemical and hormonal homeostasis, obesity is also a risk factor for the development of hypertension. In this sense, the models proposed in the current study led to an elevation in blood pressure levels. According to Lim et al. , there iAnother important aspect observed in the current study was an elevation in the percentage of liver water content in an HFHS liver in relation to that of C, even with a similar total weight. This suggests fat accumulation in this tissue, resulting mainly from the elevation of free fatty acids which, when excessive, can be synthesized in TG and deposited in the liver . NeverthIn conclusion, our study shows that approaches employing an excess of lard, and a combination of sugar and lard, promote obesity and its comorbidities. These approaches represent useful tools for studying human obesity-related disorders. An excess of sugar, however, did not present these characteristics, thus proving not to be a good model for obesity.


Good treatment responses in patients were defined as the magnitude of change from the baseline VASloudness for ≥ 30% plus CGI-I ≤ 3 points. In total, 107 patients were enrolled. Most factors were not significantly associated with the treatment effectiveness of acupuncture in tinnitus patients. Only the combination of acupoints and the number of acupuncture sessions reached statistically significant differences. Further analyzing these two factors, we confirmed that the combination of periauricular and distal acupuncture and 17 to 24 acupuncture sessions contributed to a considerably better outcome. This result would serve as a reference for clinical acupuncturists to select an appropriate acupuncture strategy in the treatment of tinnitus.An effective acupuncture treatment must comprehend the influence of various factors, but studies in this aspect remain limited. This study aimed to identify relevant factors and search for the best practical method of acupuncture for patients with tinnitus. The study was a retrospective review of patients' data with a prospective design who had subjective idiopathic tinnitus and received acupuncture between May 2012 and August 2017. Patients' demographics, tinnitus characteristics, previous diseases, underlying diseases, oral habits, audiograms, acupuncture sessions, and acupoints were recorded and analyzed. A visual analog scale (VAS Tinnitus is the perception of annoying sound without external auditory stimuli. Patients with tinnitus may have insomnia, anxiety, depression, inability to concentrate, and declining quality of life . Severe The pathophysiology of tinnitus is unclear; its treatment is poorly effective and remains a challenge . For mosIn East Asian countries, acupuncture is a usual and convenient treatment. It has been used to treat numerous diseases and symptoms, including various physiological and psychological discomforts and pain. Acupuncture therapy for tinnitus has been used for centuries, and the effect has been recommended in Chinese medical science. Acupuncture provided by well-trained physicians is relatively safe and has few side effects. Most adverse events are minor, such as bleeding, local hematoma, pain, or vegetative symptoms . SeveralIn Traditional Chinese Medicine (TCM) theory, a disease occurs primarily as a consequence of the imbalance of the Yin and Yang in a human body. Each patient has a different constitution and various diagnostic patterns of TCM, representing different degrees of Yin and Yang imbalance. Acupuncture can regulate the balance by meridians and adjust imbalance in Yin and Yang to cure a disease. An effective acupuncture treatment must comprehend the patient's constitution and TCM diagnostic patterns first , and theThis study was a retrospective review with prospectively collected data. Patients who had tinnitus and received acupuncture treatment at the departments of Otolaryngology and Chinese Medicine of Chang Gung Memorial Hospital, Keelung, from May 2012 to August 2017, were included. All patients were diagnosed with subjective tinnitus at the clinic of otolaryngology and had undergone routine assessment. The assessment included parameters listed in the data collection section below. Patients would be excluded from this study if they (1) had received <4 sessions of acupuncture for tinnitus, (2) had discontinued therapy for >1 month during acupuncture treatment, and (3) had undergone other therapies, such as medications, surgery, and biofeedback therapy for tinnitus during the period of acupuncture therapy.Since May 2012, the department of Chinese Medicine had set an acupuncture protocol with two different acupoint combinations for patients with tinnitus. This protocol was established in accordance with standard textbooks, previous research on acupuncture, and the experience of clinical acupuncturists . One groAll patients received acupuncture once or twice a week. The sterile disposable stainless needle of 0.3 mm diameter and 25 mm length was inserted into those four basic acupoints for a depth of 10–20 mm, and a needle of 0.3 mm diameter and 40 mm length was used for other distal acupoints with the approximate puncture depth of 15–30 mm. All needles were retained in each acupoint for 15–20 minutes.Regarding the number of treatment sessions, fewer treatment sessions may be the reason for unsatisfactory results, and adequate treatment sessions are required for each tinnitus patient . In our loudness) was used for measuring tinnitus loudness, and the Clinical Global Impression-Improvement scale (CGI-I) was used for measuring the treatment response to suffering from tinnitus. All patients were evaluated for VASloudness and CGI-I during the treatment period. Scores were recorded on the charts for each acupuncture session.Two primary assessment scales were used for evaluating the treatment response. The visual analog scale  very much better; (2) much better; (3) minimally better; (4) no change; (5) minimally worse; (6) much worse; and (7) very much worse. The CGI-I rating scales were employed in some studies to assess a patient's subjective perception regarding the changes in the severity of tinnitus over time , 28.loudness for ≥ 30% of the baseline VASloudness plus CGI-I is ≤ 3 points. Conversely, a patient was considered to exhibit poor treatment response if the decline in VASloudness /baseline VASloudness was < 30% or CGI-I score was ≥ 4 points.Moreover, we considered that patients exhibited a good response to acupuncture treatment if there was a decrease in VASPatients' demographics: sex, age, and body mass indexTinnitus history: location of tinnitus  and duration of tinnitus. In this study, acute tinnitus is defined as tinnitus for less than three months Diseases of the head and neck: nasopharyngeal carcinoma, radiotherapy for head and neck cancer, chronic otitis media, and perforation of the eardrumUnderlying diseases that may cause tinnitus: anemia, insomnia, thyroid diseases, diabetes mellitus, dyslipidemia, and syphilisOral habits: cigarette smoking, alcohol consumption, and betel nut chewingAudiograms of the patientsloudness, and CGI-IAcupuncture: the number of acupuncture sessions, acupoint groups (PA group or PADA group), VASDetails of the following parameters were collected and analyzed: t-test (Audiometry) were used to evaluate the relationship between each parameter and the patient's response rate to acupuncture. Also, Fisher's exact test was used to assess the differences in patients' characteristics between the PA and PADA groups, and t-test was employed to analyze the differences in audiometry and BMI. For further examining the treatment response of different acupuncture combination and acupuncture sessions, we used the paired t-test to assess the differences before and after acupuncture treatments in the changes of VASloudness and CGI-I. Unpaired t-test and Fisher's exact test were used to compare the treatment responses between the PA and PADA groups. We also use the chi-square test for comparing four groups with different numbers of acupuncture sessions and calculated the mean of percentage change (improvement) from baseline VASloudness of all patients. Odds ratio (OR) and 95% confidence intervals (95% CI) were calculated using a two-tailed test of significance (p < 0.05) for each factor, as follows: (1) when 95% CI did not include 1.0, the resulting OR of the risk factor was statistically significant; (2) if the value of the OR was >1.0, the risk was increased; and (3) if the value was <1.0, the risk was reduced. Fisher's exact test and t-test were calculated using the MATLAB program .In this study, most parameters of patients with tinnitus were dichotomous . We used descriptive statistics to describe patients' characteristics, past disease history, history of tinnitus, and factors related to tinnitus. Fisher's exact test, chi-square test (BMI), andIn total, 127 patients were diagnosed with tinnitus by otolaryngology specialists, and they received acupuncture treatments at the department of Chinese Medicine. Twenty patients were excluded because they did not meet the study requirements. Thus, 107 patients were enrolled and analyzed. Patients' demographic data and clinical characteristics were summarized in p = 0.026, p = 0.003, The univariate analysis related to patients receiving acupuncture treatments for tinnitus was shown in loudness and CGI-I points was significant in both PA and PADA groups after the acupuncture treatment  was found in the PADA group than in the PA group  patients were in the PA group and 69 (64.49%) in the PADA group. In the PA group, 24 patients had poor treatment responses, and 14 patients had good responses. In the PADA group, 42 patients responded well to acupuncture, and 27 patients did not. As for the patients' demographics, laboratory tests, and audiometry, there were no differences between the PA and PADA groups . The decp = 0.017, loudness was gradually rising with the increase of the number of acupuncture sessions as shown in In an analysis of the treatment sessions and efficacy of acupuncture, 17 to 24 sessions and over 25 sessions groups showed better response and were significantly better than 4 to 8 sessions group  local acupoints are near the area where the symptoms occur, (2) distant acupoints along the meridian, and (3) distant acupoints based on the diagnostic patterns of TCM . GeneralThe etiology of tinnitus is complex and difficult to determine. Each cause of tinnitus results in different forms of tinnitus and each of them may require a different therapeutic strategy . Tinnitup = 0.026, OR: 2.67, CI95: 1.09–6.59, In the current study, there were 38 patients 35.5%) and 69 patients (64.5%) in the PA group and PADA group, respectively. Four basic acupoints near the ear  were adopted in both groups. In the PADA group, 11 more acupoints were added according to the TCM theory and clinical research , 34, 35,.5% and 6Patients in the PADA group may have more positive thoughts about acupuncture treatment than patients in the PA group. Positive thoughts may lead to significant differences in the characteristics of the two groups of patients, so we did a further analysis in A study in South Korea reported that systemic manual acupuncture showed better effects than periauricular electroacupuncture alone. The systemic manual acupuncture includes periauricular acupoints and distal acupoints in the limbs according to the meridian system theory . Similarloudness was decreased gradually with the increase of the number of acupuncture sessions  and 3 had chronic tinnitus (longer than three months), including 1 patient who had had tinnitus for more than 1 year. Six of them receiving the acupuncture sessions were less than 24 times. Nevertheless, no definite conclusion can be reached because of the small sample size.loudness to determine the level of intensity of the tinnitus and patient-reported CGI-I to measure changes in the patients' subjective reports of suffering from tinnitus. In the present study, we defined a good treatment response as a decrease in VASloudness of ≥ 30% of the baseline VASloudness plus CGI-I ≤ 3 points through comprehensive analyses. Recently, several subjective questionnaires were used to evaluate the severity of tinnitus and effects of interventions, such as tinnitus handicap inventory (THI), tinnitus reaction questionnaire, tinnitus handicap questionnaire, and tinnitus questionnaire. Among these tools, THI has been proven to have excellent internal consistency, reliability, and significant correlations [Currently, there is still no consensus on how to assess the efficacy of tinnitus treatment. We evaluated the treatment responses by using patient-reported VASelations . These qThere are some limitations to this study. First, the study was retrospective, and there was no control group so that the placebo effect could not be eliminated. Besides, the number of acupuncture sessions and the length of treatment courses varied among patients. We know that RCTs are the “gold standard” for evidence-based medicine. But in the RCTs of acupuncture, the designs of the blind and sham acupuncture of the control group are almost impossible. The acupuncture method, the combination of acupoints, the courses of acupuncture, and even results reported are also variable by different RCTs. That was the main reason of previous systematic reviews and meta-analyses reached no conclusion as to whether acupuncture has beneficial effects on the treatments of tinnitus , 26, 36.In our study, the combination of periauricular and distal acupoints, and the patient receiving 17 to 24 acupuncture sessions, were associated with a significantly better outcome in the treatment of tinnitus patients. The results could provide a valuable reference for clinical acupuncturists to select an appropriate acupuncture strategy to treat patients with tinnitus.


We therefore carried out a Relevant studies were searched from PubMed database, CNKI, WANFANG DATA and VIP INFORMATION up to January 2012, with no language restrictions. References listed from selected papers were also reviewed. We included studies that reported the estimates of relative risks (RRs) with 95% confidence intervals (CIs) for the association between menstrual and reproductive factors and lung cancer risk. The pooled RRs were calculated after the heterogeneity test with the software Stata 11, and publication bias and sensitivity were evaluated at the same time.meta-analysis. Older age at menarche in North America women  was associated with a significant decreased risk of lung cancer. Longer length of menstrual cycle was also associated with decreased lung cancer risk . Other exposures were not significantly associated.Twenty-five articles, representing 24 independent studies, were included in this Our analysis provides evidence of the hypothesis that female sex hormones influence the risk of lung cancer in women, yet additional studies are warranted to extend this finding and to clarify the underlying mechanisms. The incidence of lung cancer is increasing in women, in contrast to that seen in men. Interestingly, the proportion of lung cancer cases in females attributable to smoking is approximately half of that seen in males. In addition, there is new evidence suggesting that estrogen receptors (ERs) ERα and ERβ have been detected on lung cancer cells in females, 5. Laboratory evidence proves that estrogen acts as a promoter for lung adenocarcinoma in a mouse model based on genetic alterations that are relevant to the human condition. These ﬁndings have suggested a hypothesis that female sex hormones, and consequently menstrual and reproductive factors, may play an important role in lung carcinogenesis.Lung cancer remains the leading cause of death from cancer among women in the United Statesmeta-analysis of these studies.Results from epidemiological studies, however, have been controversial. To evaluate the relationship between risk of lung cancer and menstrual and reproductive factors, we conducted a meta-analysis in accordance with the meta-analysis of Observational Studies in Epidemiology guidelines. We conducted a systematic literature search of the PubMed database, CNKI, WANFANG DATA and VIP INFORMATION through January 2012 by using the following search strategy:  AND (lung cancer OR lung neoplasms OR pulmonary cancer OR pulmonary neoplasms), with no restrictions. Reference lists of the chosen papers were also reviewed for other potential articles that may have been missed in the database search. We did not contact the authors of the primary studies to request addition information.We attempted to report this Studies were included in our analysis if they met the following criteria: 1) the study design was a case-control study or a cohort study; 2) the endpoint of cohort study was incidence of lung cancer; 3) the risk estimate of lung cancer related to menstrual or reproductive factors and the corresponding 95% confidence intervals (CIs) were reported; studies without existing RRs were also eligible if the relevant data presented in the study we can use to calculate crude RRs instead; 4) of the studies with the same or overlapping population published in more than one study, we included the most recent ones.Two authors independently reviewed the articles and extracted the data, any disagreement was resolved by discussion. Information was recorded for each study as follows: last name of the first author, year of publication, study location, type of study design, length of follow-up (if applicable), total person-years of observation (if applicable), studied outcome, exposure variables and categories, number of lung cancer cases, number of controls, cohort size, age range (if applicable), menopausal status of the participants (if applicable), smoking status of the participants (if applicable), adjusted RR estimates from multivariable model with corresponding 95%CIs and statistical adjustment for potential confounders of interest., including characteristics of study populations, assessments of exposure and outcome and confounding variables controlled.Instead of providing aggregate scores, we assessed the quality of individual studies by recording the key components of study designsmeta-analysis of the comparison of the highest versus the lowest category in each study. In addition, exposures to OC use and HRT use were analyzed as dichotomous variables. Because some studies reported associations for different durations of OC use and HRT use in comparison with never use, we pooled those RRs to evaluate the total effect for ever versus never use.In this reanalysis, the odds ratio (OR) and the hazard ratio (HR) were directly considered as RR. The categories of menstrual and reproductive exposure measures varied across studies, so we performed this Pooled risk estimates were calculated for exposure variables that were reported in at least five studies, which included age at menarche, length of menstrual cycle, number of pregnancies, parity (number of live births), age at first live birth, age at menopause, oral contraceptive (OC) use and hormone replacement therapy (HRT) use.Other menstrual and reproductive variables reported in less than five studies included menopause status, other hormones, type of surgery, number of difficult labour, positive history of hysterectomy; miscarriage; spont; abortion, breast feeding, period length, menstrual regularity, quantity of menstrual flow, mental tension or pains related to menses, age at first use OC, age at first use HRT, years of menstruation, time since first use OC, time since last use OC, type of HRT, lifetime estrogen dose from HRT, intrauterine device use, age at last birth, estrogen plus progestin pills, calendar year of first use OC, HRT and number of menstrual cycles up to the reference date.Q statistic at the P < 0.05 level of significance. We also calculated the I2 statistic, a quantitative measure of inconsistency across studies, which was classified as low (25%), moderate (50%) and high (50%). RRs from different studies were pooled using the fixed effect model and the random effect model based on the Mantel-Haenszel method and the Dersimonian and Laird method respectively. If there is no heterogeneity between studies, we used a fixed effect model; otherwise, we adopt the random effect model.Heterogeneity test was performed with the use of meta-analysis RR by sequentially omitting each one before pooling study-specific RRs.Subgroup analyses according to geographic region and study design were carried out to assess the potential impacts on the association. In addition, we conducted a sensitivity analysis to examine the influence of individual studies on the overall Begg's funnel plots and formally by Egger's linear regression test, 11. All statistical analyses were done using STATA version 11.0 software. A P value < 0.05 was considered statistically significant and all statistical tests were two-sided.Potential publication bias was assessed by visual inspection of et al, Zheng et al, Dorjgochoo et al and Liu et al because they provided insufficient data. Articles by Zhong et al, Qin et al, Yin et al, and Fang et al were excluded because only point estimates and 95%CI were reported without categorical variables. We further excluded one study which studied on the survival of lung cancer. Two articles reported risk estimates based on the partially overlapping Chinese population, 47, so we extracted data from Zheng et al, the more recent reference, for all menstrual and reproductive variables. Two articles reported partially overlapping data from the Czech Women's Lung Cancer Study, 48, however, Zatloukal et al reported the results separately by cell types of lung cancer, so we extracted all menstrual and reproductive data from Kubik et al. Two articles based on the China Gansu Province population database overlapped, 49, so data from the more recent reference were used. One report analyzed unpublished data collected in a long-standing hospital-based case-control study, which materials and methods were described in detail by Wynder et al, so the information of study was extracted from Wynder et al. Seow et al reported the results separately by smoking status, so we extracted two data sets from the study. Two articles reported partially overlapping data from the prospective Shanghai Women's Health Study, 39, we extracted data from Chen et al, the more recent reference, for all menstrual and reproductive variables except number of children and age at first live birth, which were only available from Weiss et al. Two articles based on the population from Fujian reported overlapping results on age at menarche, 43, so those results were extracted from the more recent reference, other related variables were extracted from Chen et al. Therefore, a total of 25 articles (18 written in English and 7 in Chinese), representing 24 independent studies, were included in this meta-analysis. A flow chart showing the study selection process is presented in Fig 1.The literature search initially identified 926 publications from PubMed, CNKI, WANFANG and VIP INFORMATION; most were excluded because they were reviews or because the exposure or endpoint was not relevant to our analysis. After scanning, 33 were retrieved for further evaluation that also let to identification of 5 more articles from their collective references. Thus, 38 articles reported associations of at least one menstrual or reproductive variable with lung cancer risk. However, we excluded the articles by Fan Tab 1. The 25 studies were published between 1988 and 2012. Of them, 13 studies had been carried out in Asia, 9 in North America and 3 in Europe. Eighteen studies reported case-control comparisons and 7 were analyses of cohorts.The characteristics of the included studies are presented in -44, 46. However, Zheng et al, Wu-Williams et al, Zhou et al, Seow et al and Matsuo et al used the oldest age at menarche as the referent category, hence these 6 adjusted RRs could not be pooled with others comparing the highest versus the lowest categories, so we calculated crude RRs according to the number of cases and controls, then we used them instead. Furthermore, we excluded one study because it did not provide the required data.Nineteen studies examined the relationship between lung cancer risk and age at menarcheI2=65.2%), but in subgroup analysis according to geographic region we found a significant decreased risk of lung cancer associated with older age at menarche in North America women .Study-specific RRs for the oldest age at menarche as compared with the youngest age ranged from 0.345 to 3.158, and the pooled RR was 0.93 (95%CI: 0.79-1.10). The RR Fig 3 represents a forest plot of the effect size distribution for the seven literatures-29, 31 that studied on length of menstrual cycle. Zheng et al and Zhou et al used the longest length of menstrual cycle as the referent category, so we calculated and used crude RRs instead. Study-specific RRs for the longest versus the shortest length of menstrual cycle ranged from 0.46 to 0.91. The combined RR suggested a significant inverse association with a 28% decreased risk of lung cancer and low between-study heterogeneity., 39, 40, among which two crude RRs, 36 were calculated according to the number of cases and controls. Study-specific RRs for highest number of pregnancies as compared with the lowest ranged from 0.69 to 1.683. The pooled RR was 1.10 (95%CI: 0.91-1.34), with low heterogeneity among the studies.Associations of lung caner risk with number of pregnancies were suggested in seven studies, 44-46 provided information on parity, of which a crude RR was calculated based on the number of cases and controls, with study-specific RRs for highest number of live births in comparison with the lowest ranging from 0.39 to 4.744, and the summary RR was 0.91 . In the eighteen studies, half studies, 45, 46 used the nulliparous women as the reference group, the pooled RR was 0.93 , whereas only three studies, 42, 44 used a parous comparison group (1-2 children) so we did not estimate the risk, others were not clearly classified.Eighteen studies, 44-46, including two crude RRs, 42 instead, and ranged from 0.49 to 1.50. The combined RR was 1.03 (95%CI: 0.88-1.21), with moderate heterogeneity across studies.Risk estimates for oldest versus youngest age at first live birth were reported in 11 studies, 44, 46 reported the relationship between age at menopause and lung cancer risk, including five crude RRs, 44, 46 calculated according to the number of cases and controls. However, two studies were excluded because one used not yet present as the referent category and the other did not provided required data. Study-specific RRs for the oldest age at menopause as compared with the youngest age ranged from 0.39 to 1.7. The pooled RR was 0.91 (95%CI: 0.70-1.17), with high heterogeneity across studies.Sixteen studies, 42, 44 reported the risk estimates for ever versus never OC use. What's more, the studies by Wu et al and Seow et al provided 2 RRs depending on duration of use, which we pooled to acquire overall RRs for ever use of 0.604 (95%CI: 0.273-1.336) for Wu et al and 0.854 (95%CI: 0.615-1.184) for Seow et al. The pooled RR of lung cancer for ever users of OC as compared with never users was 0.97 (95%CI: 0.89-1.06), with modern heterogeneity among the studies.Eight studies, 41, 44, but one study was excluded because OC use was included in HRT use. In addition, the studies by Wu et al, Baik et al and Brinton et al represented 2 RRs depending on duration of use, which we calculated to obtain overall RRs for ever use of 1.074 (95%CI: 0.749-1.539) for Wu et al, 0.948 (95%CI: 0.859-1.046) for Baik et al and 0.934 (95%CI: 0.874-0.998) for Brinton et al. The pooled RR of lung cancer for ever users versus never users of HRT was 0.99 (95%CI: 0.91-1.08), with modern heterogeneity among the studies.Risk estimates for ever versus never HRT use were reported in eight studiesmeta-analysis was omitted at a time to reflect the influence of the individual data set to the pooled RRs, and the corresponding combined RRs were not materially altered , suggesting that our results were stable and reliable.A single study involved in the Begg's funnel plot was conducted to assess the publication bias of studies . Then, the Egger's test was performed to provide statistical evidence of funnel plot symmetry. The P values for Egger's test were greater than 0.05 for all exposure variables with the exception of age at menopause  and HRT use , the results indicated publication bias for age at menopause and HRT use.The meta-analysis identified that decreased lung cancer risks were prone to present in women with longer length of menstrual cycle. We also found that age at menarche of North America women was inversely associated with lung cancer risk. Other six factors did not appear to be strongly associated with risk of this tumor. In summary, these findings support the hypothesis that estrogen exposure has an effect on the risk of lung cancer in women.Several menstrual and reproductive factors have been suggested related to lung cancer risk, however, many of these results are inconsistent. There is a common point that women are more likely to be diagnosed with lung adenocarcinoma and non-small cell lung cancer (NSCLC). Our , 51; 2) hydroxylated estrogen metabolites can undergo redox cycling to generate free radicals, which cause DNA damage and lead to carcinogenic mutations; 3) estrogens can directly stimulate the transcription of estrogen-responsive genes in the nucleus of lung cells and can also transactivate growth-factor-signaling pathways, such as the epidermal growth factor receptor (EGFR) pathway, which was involved in NSCLC growth, protection from apoptosis, and angiogenesis-55; moreover, 4) estradiol (E2) can enhance the expression of midkine (MK) protein and E2 increased MK mRNA expression in lung adenocarcinoma cells. Both estrogen and MK can induce NSCLC epithelial-mesenchymal transition, which plays an important step in the migration of lung tumor cells.Shorter length of menstrual cycle indicated an overall increase in the period of unopposed estrogen exposure, and younger age at menarche implied more menstrual cycles over the lifetime and hence longer periods of estrogen exposure in total. Women who undergo shorter length of menstrual cycle and younger age at menarche may have an increased risk of lung cancer, possibly due to more cumulative exposure to endogenous estrogen, which may be involved in the etiology of this disease. There are several lines of evidence that estrogens may promote lung tumorigenesis: 1) estrogens can exert their biological effect through two ER subtypes, ERα and ERβ, particularly ERβ, which promotes estrogen-dependent growth of lung cancer cellset al found that short length of menstrual cycle (< 27 days) were significantly more common with increasing number of variant A2 alleles. The A2 allele was thought to enhance the transcriptional activity of the CYP17 gene leading to elevated levels of estrogen-60, which may increase the risk of lung cancer.Furthermore, Henningson OC use and HRT use, as surrogates of exogenous sex hormonal exposure, seemed not to have a strong impact on lung cancer risk. This may suggest that endogenous and exogenous sex hormone play different roles in lung tumorigenesis, yet further researches using larger study populations are needed to confirm this assumption.meta-analysis. Some evidence of heterogeneity was observed throughout our study. This was partially owing to the following facts: the studies we included focused on different types of design, most of them were case-control studies; studies we used were conducted in different geographic regions, mostly Asia and North America, where people share little in the field of genetic background, lifestyle, and lung cancer incidence; and the ranges of exposure variables in most studies were inconsistent. On this occasion, subgroup analysis was carried out to explain the heterogeneity. As a result, we found that differences in geographic region might contribute to the heterogeneity between studies.Heterogeneity is often a concern in a Egger's test suggested little evidence of publication bias in our meta-analysis. We cannot preclude the possibility, as with any meta-analysis, that other unpublished studies may have been missed during our literature search. Meanwhile, we could hardly found the articles written in authors' mother tongue. Moreover, studies with null effects were less published than those with positive ones, which made it different for us to obtain.meta-analysis should be considered. First, our analysis was limited by the inconsistent categorization of the exposure variables, especially those with more than two strata. However, all adjusted RRs were estimated on the basis of the highest versus the lowest category of the exposure variables, and the wide ranges of exposure variables probably reduced this bias. Second, residual confounders were always concerned in observational studies. Although we used the reported multivariable adjusted RRs where available, we still could not exclude the probability that other unmeasured factors have influenced the real relationship. Nonetheless, our study had a noteworthy strength. As individual study had insufficient statistical power, our meta-analysis of 24 studies involving a large number of participants enhanced the power to detect significant associations and provided more reliable estimates. Moreover, our results are consistent with the hypothesis that estrogen exposure may increase the risk of lung cancer in women, but the mechanisms involved are likely to be complex. It is clear that further studies, both mechanistic and epidemiologic, are warranted in this area. Our findings provide further evidence on the public health with respect to the lung cancer prevention in women.Potential limitations of our On balance, older age at menarche in North America women  was associated with a significant decreased risk of lung cancer. Longer length of menstrual cycle was also associated with decreased lung cancer risk . The other six exposures were not significantly associated. More investigations in large and well-designed studies are needed to extend these findings and to clarify the underlying mechanisms.This study was supported by grants No.81102194 from National Natural Science Foundation of China, No.LS2010168 from Liaoning Provincial Department of Education, and grant No.00726 from China Medical Board. The authors are most grateful to all the participants in this study.No competing financial interests exist for any of the authors.


P=0.006), and lowers the risk of infection and complications  more so than does PN. The EN group had a similar risk of multiple organ failure (MOF) compared with the PN group . The use of EN was also found to significantly reduce mean hospitalization time . No publication bias was found. Our meta-analysis suggested that EN, but not PN, significantly reduced the risk of mortality, infection, and complications for patients with SAP. EN support also decreased the rate of MOF and surgical intervention. EN is recommended as an initial treatment option for patients with SAP.We conducted a comprehensive analysis to evaluate the treatment efficacy and safety of enteral nutrition (EN) and parenteral nutrition (PN) in severe acute pancreatitis (SAP) patients, and to provide a basis for their evidence based application in a clinical setting. We conducted a systematic online search of the PubMed, Web of Science, Wanfang, and China National Knowledge Infrastructure databases, from their inception to November 2017. Studies were subjected to further screening if they met the inclusion/exclusion criteria. Eleven studies were subjected to qualitative and quantitative synthesis; these included a total of 562 patients (281 for EN and 281 for PN). No significant heterogeneity across studies was found. The results indicated that EN can significantly decrease the mortality rate (relative risk [RR] = 0.43, 95% confidence interval [CI]: 0.23–0.78,  Acute pancreatitis is a common abdominal disease that can be divided into mild and severe acute pancreatitis (SAP) . The morThe present meta-analysis followed the guidelines set forth by the Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISM) checklists . No regiWe conducted a systematic online search of the PubMed, Web of Science, Wanfang, and China National Knowledge Infrastructure databases, from their inception to November 2017. The following MeSH terms and keywords were used: SAP or acute necrotizing pancreatitis; EN or enteral feeding; PN or parenteral feeding. We also reviewed reference sections for further reviews and related studies. We restricted the search languages to English and Chinese.n<30). In cases of continuing or duplicate studies, only the most recent data were used.Two authors independently performed the initial search, deleted duplicates, and screened the titles and abstracts. The study inclusion criteria were as follows: (1) design type: randomized controlled trial or cohort study; (2) study population: children or adults with SAP who required enteral or PN for at least 48 h; (3) intervention: enteral or PN. (4) Comparison: EN with PN. Exclusion criteria included (1) experimentation studies, comments, reviews, letters, and conferences abstracts, and (2) studies with very small sample sizes  sheet: first author, year of publication, mean age of EN and PN groups, sample size, sex distribution , and treatment duration. We also attempted to directly contact the corresponding author if there was any missing information. The primary outcome was mortality rate, while secondary outcomes included the infection and complication rates, surgical intervention, MOF, and mean hospitalization time.We assessed the quality of each study using the guidelines set forth by the Cochrane Library . The risI2 statistic. An I2 > 50% indicated significant heterogeneity across studies [P<0.05 was considered to be significant.We used the Stata  and RevMan 5.3 (Cochrane library) programs to analyze the data. We used the relative risks (RRs) and their 95% confidence intervals (CIs) to assess the differences between EN and PN for binary data . We also calculated the weighted mean differences (MDs) and 95% CIs to evaluate differences in mean hospitalization time. Heterogeneity across studies was assessed by Chi-square analysis and the  studies . In such studies ,15. P<0.The general characteristics of the studies included in this meta-analysis are presented in Supplementary material 1 provides a summary of the risk of bias of the included studies, and reviews the study authors’ judgements regarding the risk for their own research. Supplementary material 2 presents these data in graph format. It is extremely difficult for clinical trials to conduct blinding. Therefore, we did classify studies into the high risk bias category on the basis of reportage of a high risk of bias with respect to the blinding of participants, study personnel, and outcome assessments. Six studies were judged to have a high risk of bias during blinding, while the level of bias was unclear for seven studies. For four studies, bias risk with respect to allocation concealment was unclear. The randomized sequence generation was adequate in all studies. No attrition or reporting biases were noted.I2 = 5.5%, P=0.486) and the fixed-effect model was used for analysis of pooled results. The results indicated that EN can significantly decrease the overall mortality rate compared with PN . We used the fixed-effect model to pool data. The results indicated that the EN groups had a lower rate of infection and complication than PN groups . The results of the fixed-effect model indicated that the EN groups had a lower surgical intervention rate than the PN groups . There was no significant heterogeneity across three studies with respect to MOF . The EN groups had a similar risk of MOF to the PN groups . More details of pooled results were presented in the Seven studies reported mortality rate data. Heterogeneity across studies was low .The current meta-analysis was based on a systematical search of the available literature and found the following: (1) EN significantly decreases the risk of death in patients with SAP compared with PN, (2) patients who received EN had a lower risk of infections and complications, a lower rate of surgical interventions, and shorter mean hospitalization time compared with patients who received PN, and (3) there was no significant difference in the rate of MOF between the EN and PN groups.SAP is an acute pancreatitis associated with accumulation of peripancreatic fluid, pseudocysts, formation of pancreatic abscesses, and pancreatic necrosis. The severity of SAP was given by the degree of abnormality of the pancreas and its surrounding area. Balthazar et al.  reportedTotal gastrointestinal nutrition is the primary option for patients with SAP in early stages of the disease . HoweverIn conclusion, our meta-analysis found that EN, but not PN, significantly reduced the risk of mortality, and the infection and complication rates, in patients with SAP. EN support decreased the rate of MOF and surgical intervention. EN is thus recommended as the primary option for the management and treatment of patients with SAP.


R = 0.705, p < 0.001; R = 0.697, p < 0.001 in Test 1; R = 0.592, p = 0.0018, R = 0.528, p = 0.0067 in Test 2). These results show the GLS-DBN is feasible method for early diagnosis of PD.As a medical imaging technology which can show the metabolism of the brain, 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) is of great value for the diagnosis of Parkinson's Disease (PD). With the development of pattern recognition technology, analysis of brain images using deep learning are becoming more and more popular. However, existing computer-aided-diagnosis technologies often over fit and have poor generalizability. Therefore, we aimed to improve a framework based on Group Lasso Sparse Deep Belief Network (GLS-DBN) for discriminating PD and normal control (NC) subjects based on FDG-PET imaging. In this study, 225 NC and 125 PD cohorts from Huashan and Wuxi 904 hospitals were selected. They were divided into the training & validation dataset and 2 test datasets. First, in the training & validation set, subjects were randomly partitioned 80:20, with multiple training iterations for the deep learning model. Next, Locally Linear Embedding was used as a dimension reduction algorithm. Then, GLS-DBN was used for feature learning and classification. Different sparse DBN models were used to compare datasets to evaluate the effectiveness of our framework. Accuracy, sensitivity, and specificity were examined to validate the results. Output variables of the network were also correlated with longitudinal changes of rating scales about movement disorders . As a result, accuracy of prediction  for classification of PD and NC patients outperformed conventional approaches. Output scores of the network were strongly correlated with UPDRS and H&Y ( Parkinson's disease (PD) is a long-term degenerative disease of the central nervous system which effects 2–3% of the world's population over 65 years old, and its incidence is increasing in recent years-positron emission tomography (PET) allows for accurate diagnosis of PD, this has been increasingly acknowledged in recent years , these methods are still hampered by over-fitting and poor generalizability, due to few labeled samples in neuroimaging datasets. To solve above problems, scholars have used deep learning models with multi-parameters, e.g., deep belief network (DBN), to avoid models' poor generalizability from traditional machine learning methods , for feature learning and classification of PET images. As a deep architecture, DBN is suitable to deliver non-linear and complicated machine learning information . As an improved Restricted Boltzmann Machine (RBM) . For a GLS-RBM model, all hidden units {Fsprase in the whole layer becomes:The p is the probability distribution of the hidden unit, γ is the scale parameter, which controls the degree of sparsity, and μ is the location parameter.Where w, and the hidden layer bias b. The visible layer bias is obtained according to the original objective function. The gradient of the objective function is solved as follows:The Gradient descent algorithm is used to iteratively solve and update parameters of the function. We use the objective function with penalty to update the weight BecauseThe second item with sparse penalty is expanded as follows:In whole GLS-DBN, multiple basic GLS-RBMs can be stacked upon each other to form a deep hierarchy. The output of each GLS-RBM serves as the input of the next basic GLS-RBM at successive levels. In the last layer of GLS-DBN, a back propagation (BP) network is set, receiving the output feature vector of GLS-RBM as learned features, and adopting a gradient descent algorithm to fine-tune the weight of the whole network, thereby coordinating and optimizing the parameters of the whole DBN. The feature vector mapping of GLS-DBN is optimized and the size of the input space is simplified.Two different cohorts of PD and NC subjects was included in this study. The first cohort came from Huashan Hospital, Fudan University, Shanghai, China. Subjects were recruited from Chinese populations and totaled 300 participants: 200 NC and 100 PD patients. Before the study, follow-up data for at least 1 year from all participants was collected. Then clinicians who were unaware of the imaging results were followed up to further confirm the clinical diagnosis. Healthy controls in this study were accepted by senior movement disorders expert neurological examination, to rule out a history of psychiatric or neurologic disorders. All participants had no drug use or exposed to antipsychotic drugs.The subjects in the Huashan cohort were randomly divided into training & validation and test (Test 1) datasets. The Test 1 dataset consisted of 50 subjects, including 25 PD patients and 25 NC subjects. Due to the variability of sampling when grouping data sets, the random cross validation method is used in the training & validation dataset, which included 75 PD patients and 175 NC subjects randomly partitioned into deep learning model training (80%) and validation (20%), with 50 iterations. The purpose of multiple cross-validation was to find the optimal parameter combination. Finally, the Test 1 dataset was used to verify the performance of the trained model.The second cohort was from 904 Hospital in Wuxi, China, and included 25 NC and 25 PD patients, enrolled between 2011 and 2015. Also, before the study, necessary screening and clinical examinations from the two senior investigators of movement disorders were used to select eligible subjects. All subjects in the Wuxi cohort were used as a test dataset (Test 2) to verify the reliability and robustness of the deep learning model.P > 0.05). The study was ethically approved by the Institutional Review Boards at North Shore University Hospital and Huashan Hospital. The study was conducted in accordance with the Code of Ethics of the World Medical Association (Declaration of Helsinki) and the standards set by the local Institutional Review board and funding agencies. After a detailed explanation of the scanning procedure, each subject received written consent from each institution. During or after data collection, authors can access information that could identify all participants.The demographic information and clinical data of two cohorts are shown in All participants were asked to fast before imaging. And the whole experiment was carried out in a dimly-lit room. The equipment used in this study was Siemens Biograph 64 PET/ computed tomography . After 45 min of intravenous injection of 185 MBq of FDG, the scans were performed for about 10 min. Hanning filter is used for image reconstruction and then projection, with an axial and transaxial cut-off frequency of 0.5.v is the voxel value of the image:The pre-processing of original PET data was completed by SPM5 software . And the software platform is implemented in Matlab7.4.0 . First, through linear and non-linear transformations, PET scans from all samples were spatially normalized into Montreal Neurological Institute brain space. Then, a Gaussian filter of 10 mm FWHM was used for smooth images over three-dimension space. After that, an automated anatomic labeling template was used to remove unrelated regions in PET images. Due to individual variation in FDG uptake, finally, each PET image was normalized to the range of 0 to 1 through following formula, where Locally linear embedding (LLE)  were used to verify the performance of the trained model.Before passing through the last layer of GLS-DBN, SoftMax function, the values of the two nodes indicate scores for PD and NC, respectively  were used as indicators to measure the performance of the model. In order to further evaluate the performance of the proposed method, we used receiver operating characteristic (ROC) graph to visualize the result of contrast experiments. The area under the curve (AUC) of the ROC was also computed to quantitatively evaluate the classification performance.In addition, to verify the robust of our proposed method, we conducted a second experiment analysis and reassigned the distribution of the training & validation set and test dataset according to the H&Y. Following an automated method Kayo, , the numTo determine the optimal structure and parameters of the GLS-DBN model, including the scale parameter, location parameter, overlapping rate, and the number of hidden units, the greedy search algorithm was used in the whole training progress until the average accuracy of the validation dataset was optimized. These were chosen as the initial parameters for fine-tuning of the GLS-DBN.Finally, hyper-parameters were set: number of hidden units, scale parameter, location parameter, and overlapping rate were set to 500, 1, 0.025, and 0.2. The maximum number of iterations of GLS-RBM and BP network were 50 and 300. Using features from LLE and GLS-DBN as classifiers, the classification experiment achieved 94% accuracy distinguishing PD and NC in the validation dataset.Two different batches of data from the Huashan and Wuxi cohorts were used to validate the model's performance. To verify the recognition ability of the algorithm, the classification accuracies of different models were compared. The results are shown in As shown in r = 0.705, P < 0.0001), and HY  in Test 1, UPDRS , and HY  in Test 2.RiskScore calculated from the GLS-DBN model was significantly correlated with clinical scale value in the Test dataset, shown in These results show that RiskScore could be used as a quantitative biomarker for early diagnosis of Parkinson's disease.In this paper, we used an improved sparse DBN named GLS-DBN for the diagnosis of PD. Compared with other sparse DBN models based on different sparse penalties, our model showed better performance in classification of PD and NC, demonstrating that GLS-DBN can be used for effectively learning superior feature representation from small neuroimaging data. Results from other datasets also proved the preferable generalizability of GLS-DBN.In addition, we compared the results of other similar studies to our results. Due to differences in datasets, number of samples, and methods of feature selection and reduction, while the accuracy was not the best, our proposed method still exceeded most relevant studies. Further, the sensitivity of our result was significantly higher than those automated classifications   in the Test dataset, indicating that the features learned by GLS-DBN correlate with clinical information. To better describe the discriminability of the results, we conducted a statistical analysis of the risk values, and the distribution of RiskScore in PD and NC are shown in p < 0.01 in Test 1, 0.26 ± 0.22 and 0.72 ± 0.17, p < 0.01 in Test 2). These results indicate that this method can effectively classify PD and NC, and that RiskScore can be used as a quantitative biomarker for early diagnosis of PD.Considering the clinical effectiveness of the results, including HY and UPDRS, this paper analyzed the correlation between RiskScore and the clinical scale, shown in Despite the impressive performance of the proposed method, the method also has some limitations and disadvantages. First, trial and error was used to determine the learning rate, and the parameter values in the network structure were optimized through a large number of experiments, causing a relatively large time complexity of the algorithm. Proper selection of parameters merits further studies; we propose using optimization algorithms such as a grid search algorithm to search for the optimal parameter combination as a next step. Second, while our work has a large number of subjects compared with several recent studies, it's still not enough to generalize our experimental results. Further, our work focuses on PET features only. Multimodal data, such as MRI and diffusion tensor imaging features, can be used for feature confusion and classification. Third, our classifier is a BP network, and other classifiers such as extreme learning machine and support vector machine can be combined with DBN. Combining other classifiers with DBN would allow the last layer before BP to be features learned from the DBN model and as an input for traditional classifiers, possibly improving classification results. Finally, as our study is based on PD and NC samples, it would be meaningful and of vital importance to further grade of different forms of Parkinson's disease or distinguish idiopathic Parkinson's disease from other forms of degenerative Parkinson's disease.In this paper, we introduced a sparse feature learning framework in PD early diagnosis. GLS-DBN model accurately classifies patients into diagnostic groups with limited image processing and provides a quantitative biomarker which can predict early Parkinson's disease. Longitudinal changes of rating scales about movement disorders (UPSRS and H&Y), was significantly correlated with the output value of prediction model. In the future, our approach may be used in independent cohorts, and as an accurate biomarker, it could identify appropriate prodromal patients who might benefit from early intervention.This study was carried out in accordance with the recommendations of Ethics committee of longhua hospital affiliated to University of Traditional Chinese Medicine with written informed consent from all subjects. All subjects gave written informed consent in accordance with the Declaration of Helsinki. The protocol was approved by the longhua hospital affiliated to University of Traditional Chinese Medicine.All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.