[Comparison of the latest cancer statistics, cancer epidemic trends and determinants between China and the United States]

Objective: To provide supports for the cancer prevention and control strategies in China by comparing the disease burden, epidemic trends, 5-year relative survival rate and major determinants of common cancers between China and the United States. Methods: A descriptive secondary analysis was conducted using data extracted from the GLOBOCAN database, the Surveillance, Epidemiology, and End Results database, Global Burden of disease 2019 database, and previous studies. The main indicators included the cases of malignant tumors in different sites, the cases of deaths, the age-standardized incidence (world standard incidence) and mortality (world standard mortality), the 5-year relative survival rate, and population attributable fraction (PAF). Results: In 2022, an estimated 4.825 million new cases and 2.574 million deaths of malignant neoplasms in China. The world standard incidence rate (201.6/100 000) in China was lower than that in the United States (367.0/100 000), and the world standard mortality rate (96.5/100 000) was higher than that in the United States (82.3/100 000). Lung cancer ranked first in the disease burden of malignant tumors in China, the new cases and deaths accounted for 22.0% and 28.5% of all malignant tumors, respectively. The top three malignant tumors in China were breast cancer (11.5%), prostate cancer (9.7%) and lung cancer (9.5%), which were also among the top five causes of death. However, the second to fifth leading causes of death from malignant tumors in China were digestive system tumors (liver cancer 12.3%, stomach cancer 10.1%, colorectal cancer 9.3%, and esophageal cancer 7.3%). From 2000 to 2018, the world standard incidence of malignant tumors showed an increasing trend and the world standard mortality of malignant tumors showed a decreasing trend in China, while the world standard incidence and mortality of malignant tumors in the United States showed a significant decreasing trend after 2000. The incidence of breast cancer, colorectal cancer and thyroid cancer increased rapidly in China, while the incidence and mortality of stomach cancer, liver cancer and esophageal cancer decreased, but they still had a heavy disease burden. From 2003 to 2015, the overall 5-year relative survival rate of malignant tumors increased from 30.9% to 40.5% in China. However, with the exception of esophageal cancer, the 5-year relative survival rates of other major malignant tumors were lower than those in the United States. In 2019, the PAF of malignant tumors death attributable to potential modifiable risk factors was 48.3% in China, which was similar to the United States (49.8%). Of these, smoking was the most important attributable risk factor, and the PAF was more than 30% both in China and the United States. In addition, about 18.8% of malignant tumors were caused by preventable chronic infections, such as hepatitis B virus and Helicobacter pylori, while less than 4% of malignant tumors in the United States were caused by infection. Conclusions: China has made great progress in the prevention and treatment of malignant tumors, but it still faces a serious disease burden. The cancer spectrum is changing from developing countries to developed countries. We should pay attention to modifiable factors, take comprehensive measures, and prevent cancer scientifically.

[Exploration and validation of optimal cut-off values for tPSA and fPSA/tPSA screening of prostate cancer at different ages]

Objective: To determine the total and age-specific cut-off values of total prostate specific antigen (tPSA) and the ratio of free PSA divided total PSA (fPSA/tPSA) for screening prostate cancer in China. Methods: Based on the Chinese Colorectal, Breast, Lung, Liver, and Stomach cancer Screening Trial (C-BLAST) and the Tianjin Common Cancer Case Cohort (TJ4C), males who were not diagnosed with any cancers at baseline since 2017 and received both tPSA and fPSA testes were selected. Based on Cox regression, the overall and age-specific (＜60, 60-＜70, and ≥70 years) accuracy and optimal cut-off values of tPSA and fPSA/tPSA ratio for screening prostate cancer were evaluated with time-dependent receiver operating characteristic curve (tdROC) and area under curve (AUC). Bootstrap resampling was used to internally validate the stability of the optimal cut-off value, and the PLCO study was used to externally validate the accuracy under different cut-off values. Results: A total of 5 180 participants were included in the study, and after a median follow-up of 1.48 years, a total of 332 prostate cancer patients were included. In the total population, the tdAUC of tPSA and fPSA/tPSA screening for prostate cancer were 0.852 and 0.748, respectively, with the optimal cut-off values of 5.08 ng/ml and 0.173, respectively. After age stratification, the age specific cut-off values of tPSA in the <60, 60-<70, and ≥70 age groups were 3.13, 4.82, and 11.54 ng/ml, respectively, while the age-specific cut-off values of fPSA/tPSA were 0.153, 0.135, and 0.130, respectively. Under the age-specific cut-off values, the sensitivities of tPSA screening for prostate cancer in males <60, 60-70, and ≥70 years old were 92.3%, 82.0%, and 77.6%, respectively, while the specificities were 84.7%, 81.3%, and 75.4%, respectively. The age-specific sensitivities of fPSA/tPSA for screening prostate cancer were 74.4%, 53.3%, and 55.9%, respectively, while the specificities were 83.8%, 83.7%, and 83.7%, respectively. Both bootstrap's internal validation and PLCO external validation provided similar results. The combination of tPSA and fPSA/tPSA could further improve the accuracy of screening. Conclusion: To improve the screening effects, it is recommended that age-specific cut-off values of tPSA and fPSA/tPSA should be used to screen for prostate cancer in the general risk population.

[Comparison of efficacy between short-term personalized vestibular rehabilitation supervised by special personnel and fixed vestibular rehabilitation on recurrent peripheral vertigo]

Objective: To explore the efficacy of short-term personalized vestibular rehabilitation supervised by special personnel (ST-PVR) versus fixed vestibular rehabilitation (FVR) on decompensated recurrent peripheral vertigo. Methods: A randomized controlled trial was carried out. Patients diagnosed with decompensated recurrent vertigo in the clinic of Eye & ENT Hospital, Fudan University from January to December 2018 were randomly allocated into FVR and ST-PVR groups via computer-generated randomization. The FVR group received fixed scheme involving gaze stabilization exercises, habituation exercises, balance and gait training, while the ST-PVR group received individualized training programs based on symptoms and vestibular function examination results, with adjustments made according to the progress of recovery. Patient symptoms and vestibular function improvement were assessed using the dizziness handicap inventory (DHI), activities-specific balance confidence (ABC), self-rating anxiety scale (SAS), caloric test, and sensory organization test (SOT) at 2, 4, and 8 weeks of treatment. Results: A total of 44 patients were included, including 16 males and 28 females, with an average age of (50.6±13.5) years. There were 21 cases in the FVR group and 23 cases in the ST-PVR group. In the ST-PVR group, DHI score (49.5±26.8 vs 61.3±21.4, P=0.046) and SAS score (39.1±7.8 vs 44.3±6.6, P=0.021) significantly improved after 2 weeks of treatment, while significant improvement occurred only after 8 weeks of treatment in the FVR group (DHI score: 28.1±15.9 vs 53.1±18.5, P=0.001; SAS score: 35.3±6.7 vs 43.1±8.4, P=0.010). There was no significant change of ABC score in the FVR group after 8 weeks of treatment (86.5±12.9 vs 83.4±18.1, P=0.373), while a significant improvement was observed in the ST-PVR group after 4 weeks of treatment (83.6±15.2 vs 78.4±15.1, P=0.015). The caloric test results showed that after 8 weeks of treatment, the proportion of patients with unilateral weakness<25% increased in both groups [FVR group: 57.1% (12/21) vs 9.5% (2/21), P=0.001; ST-PVR group: 52.2% (12/23) vs 17.4% (4/23), P=0.014]. In the ST-PVR group, the proportion of patients with dominant preference≤25% significantly increased [91.3% (21/23) vs 60.9% (14/23), P=0.016], while there was no significant change in the FVR group [61.9 (13/21) vs 57.1% (12/21), P=0.500]. The proportion of patients with SOT score≥70 in the ST-PVR group increased significantly after 2 weeks of treatment [69.6% (16/23) vs 30.4% (7/23), P=0.009], while the FVR group showed a significant increase only after 8 weeks of treatment [81.0% (17/21) vs 42.9% (9/21), P=0.012]. Conclusion: Both FVR and ST-PVR effectively promote vestibular compensation by improving objective vestibular functions and relieving subjective symptoms and anxiety of the patients with decompensation recurrent vertigo, while ST-PVR might shorten the recovery time and increase balance confidence.

Improved Measurement of the Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

Reactor neutrino experiments play a crucial role in advancing our knowledge of neutrinos. In this Letter, the evolution of the flux and spectrum as a function of the reactor isotopic content is reported in terms of the inverse-beta-decay yield at Daya Bay with 1958 days of data and improved systematic uncertainties. These measurements are compared with two signature model predictions: the Huber-Mueller model based on the conversion method and the SM2018 model based on the summation method. The measured average flux and spectrum, as well as the flux evolution with the ^{239}Pu isotopic fraction, are inconsistent with the predictions of the Huber-Mueller model. In contrast, the SM2018 model is shown to agree with the average flux and its evolution but fails to describe the energy spectrum. Altering the predicted inverse-beta-decay spectrum from ^{239}Pu fission does not improve the agreement with the measurement for either model. The models can be brought into better agreement with the measurements if either the predicted spectrum due to ^{235}U fission is changed or the predicted ^{235}U, ^{238}U, ^{239}Pu, and ^{241}Pu spectra are changed in equal measure.

Precision Measurement of Reactor Antineutrino Oscillation at Kilometer-Scale Baselines by Daya Bay

We present a new determination of the smallest neutrino mixing angle θ_{13} and the mass-squared difference Δm_{32}^{2} using a final sample of 5.55×10^{6} inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample is selected from the complete dataset obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are sin^{2}2θ_{13}=0.0851±0.0024, Δm_{32}^{2}=(2.466±0.060)×10^{-3}  eV^{2} for the normal mass ordering or Δm_{32}^{2}=-(2.571±0.060)×10^{-3}  eV^{2} for the inverted mass ordering.

First Measurement of High-Energy Reactor Antineutrinos at Daya Bay

This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12 MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10 MeV is rejected with a significance of 6.2 standard deviations. A 29% antineutrino flux deficit in the prompt energy region of 8-11 MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-Q_{β} isotopes in commercial reactors.

Joint Determination of Reactor Antineutrino Spectra from ^{235}U and ^{239}Pu Fission by Daya Bay and PROSPECT

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

[Application of multi-stage competing risk model to survival data]

The traditional proportional hazard model is commonly used to investigate the association between main outcome and predictor variables. However, the endpoints in medical studies are often not unique. The analyses of labeling other competing outcomes other than the main outcome as censored data will theoretically lead to a biased estimate of the risk of main outcome. Although the traditional competitive risk model can adjust the influence of other outcomes on the risk of the main outcome, it can not directly compare the differences on the risks of different outcomes. The multi-state competing risk model provides a relatively suitable solution for this problem. In this study, based on a previously published follow-up data set for prostate cancer patients, we developed traditional proportional hazard model, traditional competitive risk model, and multi-state competing risk model, respectively. By comparing the advantages and disadvantages of the three models with the same survival data, we clarified the clinical application value of the multi-state competitive risk model in survival data with multiple outcomes.

[Potential pleiotropism of cancer-related single nucleotide polymorphisms among Chinese population]

Objective: To investigate the potential pleiotropism of cancer-related single nucleotide polymorphisms (SNPs) among Chinese population. Methods: Based on the catalogue of GWAS jointly constructed by the National Human Genome Research Institute and the European Institute of Bioinformatics, according to population origin (Chinese population and non-Chinese population) and disease traits (cancer and non-cancer traits). All SNPs found by GWAS before August 2020 were divided into four categories: cancer in Chinese population, non-cancer in Chinese population, cancer in non-Chinese population and non-cancer in non-Chinese population. The number, correlation and linkage of the four categories of SNPs were described. Results: By August 2020, a total of 196 813 SNPs from 4 096 GWAS were included in the GWAS directory. The information that SNPs refer to unknown or were not related to the disease was excluded, and 117 441 independent SNPs were finally included. There were 619 SNPs related to cancer and 9 569 SNPs related to non-cancer disease in Chinese population, respectively. There were 4 624 SNPs related to cancer and 106 448 SNPs related to non-cancer disease (trait) in non-Chinese population, respectively. Three SNPs, rs2736100, rs6983267 and rs401681, were associated with two or more types of cancer in both Chinese and non-Chinese populations. Seven SNPs, rs7705526, rs2736100, rs10993994, rs2735839, rs4430796, rs174537 and rs9271588, were associated with cancer and non-cancer diseases in both Chinese and non-Chinese populations, respectively. Conclusion: There is a potential pleiotropism of cancer-related SNPs in Chinese population.

Effects of phytosterol supplementation on growth performance, serum lipid, proinflammatory cytokines, intestinal morphology, and meat quality of white feather broilers

The aim of this study was to evaluate the effects of dietary phytosterol (PS) addition at different levels on growth performance, serum lipid, proinflammatory cytokines, intestinal morphology, and meat quality in broilers. A total of 600, 1-day-old male broilers were allocated into five groups with six replicates and were fed a basal diet supplemented with 0 (control group), 10, 20, 40, or 80 mg/kg PS for 42 days. Compared with the control group, the administration of PS at doses of 40 and 80 mg/kg significantly increased the average daily feed intake and average daily gain of broilers during the experimental period. Similarly, PS at a dosage of 20 and 40 mg/kg increased the concentrations of interleukin-1β, interferon-γ, interleukin-2, and interleukin-6 but decreased triglyceride, total cholesterol, and low-density lipoprotein cholesterol content of serum (P < 0.05). Dietary PS at less than or equal to 40 mg/kg level increased (P < 0.05) villus height, and villus height to crypt depth ratio in the duodenum and ileum. Supplementing PS increased the pH value at 45 min post-mortem and decreased drip loss and shear force of breast muscle (P < 0.05). Dietary PS administration at 20 and 40 mg/kg decreased malondialdehyde accumulation but increased total antioxidant capacity and superoxide dismutase activity of breast muscle compared with the control group (P < 0.05). PS increased the concentrations of total amino acids and flavor amino acids as well as eicosapentaenoic acid, docosahexaenoic acid, and total polyunsaturated fatty acids but decreased saturated fatty acids in breast muscle (P < 0.05). It was concluded that dietary PS supplementation, especially at 40 mg/kg, could improve growth performance, serum lipid, proinflammatory cytokines, intestinal morphology, and meat quality in broilers, providing insights into its application as a potential feed additive in broiler production.

Improved Constraints on Sterile Neutrino Mixing from Disappearance Searches in the MINOS, MINOS+, Daya Bay, and Bugey-3 Experiments

Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{μe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13  eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}.

Directional massless Dirac fermions in a layered van der Waals material with one-dimensional long-range order

One or a few layers of van der Waals (vdW) materials are promising for applications in nanoscale electronics. Established properties include high mobility in graphene, a large direct gap in monolayer MoS₂, the quantum spin Hall effect in monolayer WTe₂ and so on. These exciting properties arise from electron quantum confinement in the two-dimensional limit. Here, we use angle-resolved photoemission spectroscopy to reveal directional massless Dirac fermions due to one-dimensional confinement of carriers in the layered vdW material NbSi_0.45Te₂. The one-dimensional directional massless Dirac fermions are protected by non-symmorphic symmetry, and emerge from a stripe-like structural modulation with long-range translational symmetry only along the stripe direction as we show using scanning tunnelling microscopy. Our work not only provides a playground for investigating further the properties of directional massless Dirac fermions, but also introduces a unique component with one-dimensional long-range order for engineering nano-electronic devices based on heterostructures of vdW materials.

[Value of dual-energy CT-based volumetric iodine-uptake in the evaluation of chemotherapy efficacy in advanced gastric cancer]

Objective: To explore the value of dual-energy CT-based volumetric iodine-uptake (VIU) in the evaluation of chemotherapy efficacy in advanced gastric cancer. Methods: Inclusion criteria of subjects: (1) without previous systematic therapy; (2) with complete clinical information before and after chemotherapy; (3) without contraindications of chemotherapy. Exclusion criteria of subjects: (1) unfinished duration and times of chemotherapy; (2) unmeasurable primary lesions; (3) poor imaging quality or poor gastric filling. Clinical and image data of 52 patients with advanced gastric cancer who were diagnosed by pathology from gastroscopic biopsy, and needed chemotherapy evaluated by imaging and clinical information in the First Affiliated Hospital of Wenzhou Medical University from February 2017 to February 2018 were collected and analyzed. Of 52 patients, 38 were male and 14 were female with the median age of 65 (31-88) years old. All the patients underwent a dual-energy, dual phase-enhanced CT scanning before chemotherapy and after the third chemotherapy session. The parameters of the lesions measured before and after chemotherapy in portal vein phase were as follows: the maximum diameter (the largest diameter among those measured in the cross-sectional, coronal, and sagittal planes), average CT value (the regions of interest were manually pinpointed under cross-sectional planes with largest diameter of the tumor, which did not include regions less than 2 mm to the edge of the tumor) and VIU (lesion volume × iodine concentration). The change rates of maximum lesion diameter, average CT value and VIU before and after chemotherapy were calculated [(post-chemotherapy parameters-pre-chemotherapy parameters)/ pre-chemotherapy parameters]. The efficacy of chemotherapy was evaluated by RECIST 1.1 (the change of maximum tumor diameter after chemotherapy), Choi (the change of average CT value after chemotherapy) and VIU (the change of VIU after chemotherapy), respectively, which was categorized by complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). Patients with CR, PR, and SD were assigned to the effective group, while those with PD were classified as the ineffective group. Paired t - test or Wilcoxon signed ranks test was used to compare the changes of parameters before and after chemotherapy, whereas Spearman correlation analysis and Kappa test were used for the correlation analysis and the consistency test between the three evaluation criteria (Kappa≥0.75 indicated good consistency). Results: After chemotherapy, the average CT value [(74.01±16.75) HU vs. (81.06±15.87) HU, t=2.202, P=0.030] and median VIU (668.53×10(2) μg vs. 272.52×10(2) μg, Z=4.761, P<0.001) decreased significantly, while the difference of the maximum diameter was not statistically significant [(66.71±34.49) mm vs. (78.45±35.62) mm, t=1.708, P=0.091]. The median change rate of VIU (-53.33%) was greater than that of CT values (-5.75%) with significant difference (Z=-5.408, P<0.001). According to the RECIST 1.1 criteria, 47 patients (90.4%, including 19 with PR and 28 with SD) were effective and 5 patients (9.6%) were ineffective. According to the Choi criteria, 45 patients (86.5%, including 37 with PR and 8 with SD) were effective and 7 patients (13.5%) were ineffective. According to the VIU criteria, 46 patients (88.5%, including 41 with PR and 5 with SD) were effective and 6 patients (11.5%) were ineffective. Efficacy comparison among these three criteria showed no significant difference (χ(2)=0.377, P=0.828). As compared to RECIST 1.1 evaluation, the proportion of PR evaluated by Choi and VIU was significantly higher (χ(2)=16.861, P<0.001), whereas the proportion of SD was significantly lower (χ(2)=24.089, P<0.001). There was no significant difference in the proportions of PR and SD between VIU and Choi criteria (χ(2)=0.887, P=0.346). Consistency and correlation analysis showed that the VIU and Choi evaluation criteria presented the highest consistency and correlation (Kappa=0.912, P<0.001; r=0.916, P<0.001). Conclusion: VIU is a feasible parameter for the evaluation of chemotherapy efficacy in advanced gastric cancer, and may be more sensitive than the evaluation criteria based on maximum diameter or change of CT value in the tumor.

Extraction of the ^{235}U and ^{239}Pu Antineutrino Spectra at Daya Bay

This Letter reports the first extraction of individual antineutrino spectra from ^{235}U and ^{239}Pu fission and an improved measurement of the prompt energy spectrum of reactor antineutrinos at Daya Bay. The analysis uses 3.5×10^{6} inverse beta-decay candidates in four near antineutrino detectors in 1958 days. The individual antineutrino spectra of the two dominant isotopes, ^{235}U and ^{239}Pu, are extracted using the evolution of the prompt spectrum as a function of the isotope fission fractions. In the energy window of 4-6 MeV, a 7% (9%) excess of events is observed for the ^{235}U (^{239}Pu) spectrum compared with the normalized Huber-Mueller model prediction. The significance of discrepancy is 4.0σ for ^{235}U spectral shape compared with the Huber-Mueller model prediction. The shape of the measured inverse beta-decay prompt energy spectrum disagrees with the prediction of the Huber-Mueller model at 5.3σ. In the energy range of 4-6 MeV, a maximal local discrepancy of 6.3σ is observed.

Orbital-Selective Kondo Entanglement and Antiferromagnetic Order in USb_{2}

In heavy-fermion compounds, the dual character of f electrons underlies their rich and often exotic properties like fragile heavy quasiparticles, a variety of magnetic orders and unconventional superconductivity. 5f-electron actinide materials provide a rich setting to elucidate the larger and outstanding issue of the competition between magnetic order and Kondo entanglement and, more generally, the interplay among different channels of interactions in correlated electron systems. Here, by using angle-resolved photoemission spectroscopy, we present the detailed electronic structure of USb_{2} and observe two different kinds of nearly flat bands in the antiferromagnetic state of USb_{2}. Polarization-dependent measurements show that these electronic states are derived from 5f orbitals with different characters; in addition, further temperature-dependent measurements reveal that one of them is driven by the Kondo correlations between the 5f electrons and conduction electrons, while the other reflects the dominant role of the magnetic order. Our results on the low-energy electronic excitations of USb_{2} implicate orbital selectivity as an important new ingredient for the competition between Kondo correlations and magnetic order and, by extension, in the rich landscape of quantum phases for strongly correlated f electron systems.

[A survey of risk factors and quality of life in female medical staff with urinary incontinence]

OBJECTIVE

To explore risk factors of urinary incontinence (UI) and influences of UI on quality of life in female medical staff from Beijing.

METHODS

One hundred and forty-six female medical personnel were included in the present study through the convenient sampling method in Peking University First Hospital. The questionnaires contained the following information: demographic information, daily urination condition, the severity of UI [international consultation on incontinence questionnaire short form (ICI-Q-SF)], and the influences of UI on quality of life (QOL). We excluded the subjects who were in pregnancy or had urinary infection, neurogenic bladder, or urethral stricture. We used SPSS 21.0 software (IBM Corp, Armonk, NY) for statistical analysis. The Kolmogorov-Smirnov test determined the normality of the continuous variables. Means and standard deviation presented continuous variables in normality. Median and range presented continuous variables without normality. Frequency and percentile were used to present categorical or ranked variables.

RESULTS

There were 63 out of 146 (43.2%) female medical staff suffering from UI. The mean age and body mass index of the whole study cohort were (39.4±9.9) years and (22.3±3.4) kg/m². The median delivery times of all the subjects were 1 time (range: 0-3 times). Fifty out of 146 (34.2%) subjects had transvaginal delivery history. Chronic constipation was diagnosed in 32 subjects (21.9%). No significant difference in daytime micturition and nocturia times were found between the UI and non-UI subjects. According to the multivariate analysis, chronic constipation (OR=4.95, 95%CI=1.81-13.53, P=0.002) and transvaginal delivery history (OR=3.50, 95%CI=1.49-8.21, P=0.004) were independent risk factors for UI. The non-UI subjects had superior quality of life than the UI subjects in terms of incontinence quality of life (I-QOL) total scores and all sub-scores of avoidance and limiting behaviors, psychosocial impacts, and social embarrassment (P<0.001). In addition, avoidance and limiting behaviors (r=-0.449, P<0.001), psychosocial impacts (r=-0.538, P<0.001), and social embarrassment (r=-0.454, P<0.001) of the 63 UI subjects were equally influenced by the incontinence symptom.

CONCLUSION

UI is not uncommon in female medical staff. The quality of life of medical faculty is influenced by UI in terms of avoidance and limiting behaviors, psychosocial impacts, and social embarrassment. Chronic constipation and transvaginal delivery history were independent risk factors for UI.

Dirac nodal surfaces and nodal lines in ZrSiS

Topological semimetals are characterized by symmetry-protected band crossings, which can be preserved in different dimensions in momentum space, forming zero-dimensional nodal points, one-dimensional nodal lines, or even two-dimensional nodal surfaces. Materials harboring nodal points and nodal lines have been experimentally verified, whereas experimental evidence of nodal surfaces is still lacking. Here, using angle-resolved photoemission spectroscopy (ARPES), we reveal the coexistence of Dirac nodal surfaces and nodal lines in the bulk electronic structures of ZrSiS. As compared with previous ARPES studies on ZrSiS, we obtained pure bulk states, which enable us to extract unambiguously intrinsic information of the bulk nodal surfaces and nodal lines. Our results show that the nodal lines are the only feature near the Fermi level and constitute the whole Fermi surfaces. We not only prove that the low-energy quasiparticles in ZrSiS are contributed entirely by Dirac fermions but also experimentally realize the nodal surface in topological semimetals.

[Preliminary application of one-step hybrid operation in the treatment of carotid artery occlusion]

Objective: To evaluate the prognosis and surgical complication of the recanalization treatments for internal carotid artery (ICA) occlusion by using one-step hybrid carotid endarterectomy and endovascular surgery. Methods: Retrospective analysis was performed on the clinical data and follow-up data of 22 patients with occluded ICA treated by one-step hybrid surgery. Difference in Barthel score and occurrence of ischemic stroke were compared with surgical group and conventional group which was treated by oral taking anti-platelet drugs. Further, the complications were analyzed to evaluate the safety and effectiveness of the surgery. Results: The difference in ischemic event rate and Barthel scores improvement between the two groups were significant. Occlusive ICAs in 19 cases were recanalized successfully. The possibility of brain hyperperfusion related to the surgery was 10.5% (2/19) while the possibility of carotid artery cavernous fistula was 9.1% (2/22). We also observed rare dissecting ICA caused by the treatment (4.5%) and distal restenosis (5.3%). Conclusions: One-step hybrid carotid endarterectomy and endovascular surgery could help recanalize the ICA, improve the blood supply and improve the prognosis. It's a safe and effective treatment for ICA occlusion.

Measurement of the Electron Antineutrino Oscillation with 1958 Days of Operation at Daya Bay

We report a measurement of electron antineutrino oscillation from the Daya Bay Reactor Neutrino Experiment with nearly 4 million reactor ν[over ¯]_{e} inverse β decay candidates observed over 1958 days of data collection. The installation of a flash analog-to-digital converter readout system and a special calibration campaign using different source enclosures reduce uncertainties in the absolute energy calibration to less than 0.5% for visible energies larger than 2 MeV. The uncertainty in the cosmogenic ^{9}Li and ^{8}He background is reduced from 45% to 30% in the near detectors. A detailed investigation of the spent nuclear fuel history improves its uncertainty from 100% to 30%. Analysis of the relative ν[over ¯]_{e} rates and energy spectra among detectors yields sin^{2}2θ_{13}=0.0856±0.0029 and Δm_{32}^{2}=(2.471_{-0.070}^{+0.068})×10^{-3}  eV^{2} assuming the normal hierarchy, and Δm_{32}^{2}=-(2.575_{-0.070}^{+0.068})×10^{-3}  eV^{2} assuming the inverted hierarchy.

[An study on the incidence of heat stroke and explore it's prediction model in Pudong New Area of Shanghai from 2013-2017]

Objective: To know the incidence of heat stroke and explore it's prediction model in Pudong New Area of Shanghai. Methods: An epidemiological investigation was conducted on heat stroke cases in Pudong New Area of Shanghai from 2013 to 2017. Daily temperature data during this period were collected to explore it's influence. Results: 246 heat stroke cases were reported and investigated, 70.3% (173/246) of them were male. 170 cases are severe heat stroke, accounting for 69.1%. 28 patients died, accounting for 11.4% of all cases of heat stroke, and 16.5% (28/170) of severe heat stroke cases. Thermoplegia (56.5%, 96/170) was the most popular type among severe heat stroke cases. Heat prostration, heat cramps and mixed type account for 17.1% (29/170) , 12.4% (21/170) and 14.0% (24/170) respectively. Scatter plot and linear regression demonstrated that there was a significant linear relation between number of high temperature days and number of heat stroke cases (P<0.01) . And the prediction model is: Predictive number of annual heat stroke cases=β×Number of annual high temperature days+Intercept. Leave-one-out cross validation result shows that the predictive number of annual heat stroke cases from 2013 to 2017 were 85.7%, 90.9%, 83.3%, 91.9 and 84.3% respectively. Conclusion: There was a significant linear relation between number of high temperature days and number of heat stroke cases in Pudong New Area. The related work arrangement for heat stroke prevention could be well planed according to the prediction model.

Evolution of the Reactor Antineutrino Flux and Spectrum at Daya Bay

The Daya Bay experiment has observed correlations between reactor core fuel evolution and changes in the reactor antineutrino flux and energy spectrum. Four antineutrino detectors in two experimental halls were used to identify 2.2 million inverse beta decays (IBDs) over 1230 days spanning multiple fuel cycles for each of six 2.9 GW_{th} reactor cores at the Daya Bay and Ling Ao nuclear power plants. Using detector data spanning effective ^{239}Pu fission fractions F_{239} from 0.25 to 0.35, Daya Bay measures an average IBD yield σ[over ¯]_{f} of (5.90±0.13)×10^{-43}  cm^{2}/fission and a fuel-dependent variation in the IBD yield, dσ_{f}/dF_{239}, of (-1.86±0.18)×10^{-43}  cm^{2}/fission. This observation rejects the hypothesis of a constant antineutrino flux as a function of the ^{239}Pu fission fraction at 10 standard deviations. The variation in IBD yield is found to be energy dependent, rejecting the hypothesis of a constant antineutrino energy spectrum at 5.1 standard deviations. While measurements of the evolution in the IBD spectrum show general agreement with predictions from recent reactor models, the measured evolution in total IBD yield disagrees with recent predictions at 3.1σ. This discrepancy indicates that an overall deficit in the measured flux with respect to predictions does not result from equal fractional deficits from the primary fission isotopes ^{235}U, ^{239}Pu, ^{238}U, and ^{241}Pu. Based on measured IBD yield variations, yields of (6.17±0.17) and (4.27±0.26)×10^{-43}  cm^{2}/fission have been determined for the two dominant fission parent isotopes ^{235}U and ^{239}Pu. A 7.8% discrepancy between the observed and predicted ^{235}U yields suggests that this isotope may be the primary contributor to the reactor antineutrino anomaly.

[Comparative analysis of the ankle joints in juvenile male soccer players with imaging]

OBJECTIVE

To investigate the characteristics of children male soccer players' ankle imaging features.

METHODS

From October 2015 to February 2016, a total of 32 male children players of two soccer clubs in Guangzhou were enrolled in this study.The ages of all cases were from 10 to 14 years, average age was (11.3±0.9) years.A total of 15 male children in region ordinary primary and secondary school students were set as control group, ages were from 10 to 14 years, average age was (12.1±1.2) years. All objects' ankle were examined by X-ray for positive and lateral positions; routine CT scanning and then on the workstation restructuring for axial, coronal and sagittal slices; and examined by MR. MR scan was with special surface coil for ankle joint for horizontal axis T2WI; coronal T1WI; coronary proton density weighted imaging (PWI); sagittal T2WI with fat suppression; sagittal PWI with isotropic and fat suppression sequence of fast field echo. The ankle bone morphological structures were observed on X-ray; the ankle bone mineral density, cortical bone thickness and sesamoid bone quantity was being observed and measured on CT; and the tenosynovitis, Achilles tendinitis, synovitis, and cancellous bone edema signal were observed on MR.

RESULTS

For study group, a total of 32 cases and 64 ankles joints were completed by X-ray, CT and MR examination.A total of 15 cases and 30 ankles joints were completed by X-ray in control group, 26 ankle joints were completed by CT scan and 22 ankle joints were completed by MR examination.X-ray examination showed there was no statistically significant difference between the two groups in ankle bone structure.CT showed that navicular bone CT value was (296±82) HU in research group and navicular bone CT value was (266±107) HU in control group, the difference was statistically significant (P=0.03). MR showed the incidence of diseases in research group that the tendon sheath peripheral inflammation was 92.2% (59/64), Achilles tendon lesions was 18.8%(12/64), edema of cancellous bone was 73.4% (47/64) , lateral malleous ligaments injuried was 43.8%(28/64), synovitis or effusion in posterior ankle was 87.5% (56/64). The incidence of diseases in control group was that tendon sheath peripheral inflammation was 31.8%(7/22), Achilles tendon lesions was 0/22, edema of cancellous bone was 0/22, lateral malleous ligaments injuried was 0/22, synovitis or effusion in posterior ankle was 54.5% (12/22). There was statistically significant difference between these two groups (all P<0.05).

CONCLUSION

Compared with the control group, children's male soccer players ankle bone structure, bone cortex thickness and bone mineral density there were no obvious difference. In the tenosynovitis, Achilles tendinitis, synovitis, bone marrow edema, lateral malleous ligaments injuried were significantly higher than the control group.

[Discussion of breast cancer screening model in China]

Cancer screening has been considered as double-edged sword with both advantages and disadvantages. For decades, there have been strong interests in screening strategies for the early detection of cancers to reduce the mortality, especially breast X-ray(mammography)screening. However, several evidences also suggested that the benefit of reduction of breast-cancer mortality with mammography might become a problem due to the repeat mammography, subsequent biopsies, and overdiagnosis. And different screening strategies with different models, different intervals, and different target populations also incurred debates. After systematical analysis and discussion, we suggested to focus on high-risk population, improve the accuracy of screening technique, conduct the informed consent of participants, and explore individual screening mode in the screening of breast cancer.

Comparative quantitative trait locus mapping of maize flowering-related traits in an F2:3 and recombinant inbred line population

Flowering-related traits in maize are affected by complex factors and are important for the improvement of cropping systems in the maize zone. Quantitative trait loci (QTLs) detected using different materials and methods usually vary. In the present study, 266 maize (Zea mays) F2:3 families and 301 recombinant inbred lines (RIL) derived from a cross between 08-641 (founding parent from southeast China) and Ye478 (founding parent from China) were evaluated for four flowering-related traits, including days to tasseling (DTT), days to pollen shedding (DPS), days to silking (DTS), and anthesis-silking interval. Sixty-six QTLs controlling the target traits were detected in the F2:3 and RIL populations via single environment analysis and joint analysis across all environments (JAAE). The QTLs explained 0.8-13.47% of the phenotypic variation, with 12 QTLs explaining more than 10%. The results of meta-QTL (MQTL) analysis indicated that 41 QTLs could be integrated into 14 MQTLs. One MQTL included 2.9 QTLs, ranging from two to ten QTLs for one to three traits. QTLs, including MQTL1-1 and MQTL9-1, were detected across the F2:3 and RIL populations via SAE and JAAE. Among the MQTLs, nine QTLs were integrated into MQTL9-1 and affected DTT, DPS, and DTS, with the favored allele being derived from 08-641. MQTL3-2 showed high phenotypic variation and was suitable for fine mapping to determine the genetic mechanisms of flowering. MQTL3-2 could be applied to improve inbred lines using marker-assisted selection.

Proteome analysis of tobacco leaves reveals dynamic changes in protein expression among different cultivation areas

The leaves of tobacco plants were used to analyze differences in protein content of tobacco grown in the four main flue-cured tobacco-producing areas of Sichuan Province, China. An improved protein extraction method, isoelectric focusing/sodium dodecyl sulfate-polyacrylamide gel electrophoresis two-dimensional gel electrophoretic separation, was used to extract and separate total protein from tobacco leaves. Proteomic maps with relatively high resolution and repeatability were produced. At isoelectric points 4 to 7 and molecular weight ranging from 20-100 kDa, we detected 1032, 1030, 1019, and 1011 clearly visible protein spots in tobacco leaves from the four study areas. Proteome comparison between these protein spots showed that 119 spots with a greater than 2-fold change in expression quantity contributed to the variation in expression. Of which, 115 were successfully identified and annotated. According to the annotation results, these proteins participate in photosynthesis, energy metabolism, mineral nutrition, terpene metabolism, defensive reaction, and other physiological and biochemical processes. This study preliminarily explains the effects of ecological conditions on the physiological metabolism of tobacco leaves and how such effects directly or indirectly contribute to tobacco leaf quality.

Collective nature of spin excitations in superconducting cuprates probed by resonant inelastic X-ray scattering

We used resonant inelastic x-ray scattering (RIXS) with and without analysis of the scattered photon polarization, to study dispersive spin excitations in the high temperature superconductor YBa_{2}Cu_{3}O_{6+x} over a wide range of doping levels (0.1≤x≤1). The excitation profiles were carefully monitored as the incident photon energy was detuned from the resonant condition, and the spin excitation energy was found to be independent of detuning for all x. These findings demonstrate that the largest fraction of the spin-flip RIXS profiles in doped cuprates arises from magnetic collective modes, rather than from incoherent particle-hole excitations as recently suggested theoretically [Benjamin et al. Phys. Rev. Lett. 112, 247002 (2014)]. Implications for the theoretical description of the electron system in the cuprates are discussed.

Variation of genomic DNA methylation in the nitrate reductase gene of sibling tobacco (Nicotiana tabacum) cultivars

To better understand genomic DNA methylation in sibling plant cultivars, methylation-sensitive amplification polymorphism analysis was used to investigate two sibling tobacco cultivars, Yunyan85 and Yunyan87, and their two parents, K326 and Yunyan No. 2. Differences in the degree of genomic DNA methylation were found among the four tobacco cultivars. Compared with parents, the two sibling cultivars had fewer methylated sites. Twenty-nine methylation-sensitive amplification polymorphism fragments that exhibited methylation alteration in the four tobacco cultivars were recovered and sequenced. BLAST (nucleotide BLAST) searches showed that two of the 29 sequences have 99% similarity with nucleotides 1442-1694 of the nia-1 gene and the other 27 sequences contain GC, CAAT or TATA box. The nitrate reductase genes from Yunyan87, K326 and Yunyan No. 2 were found to be identical; however, the third intron of the nitrate reductase gene from Yunyan85 was different compared to the third introns of Yunyan87, K326 and Yunyan No. 2. We conclude that methylation alteration of promoter regions could be responsible for the different phenotypes in tobacco and that introns of the nitrate reductase gene can vary as a result of intra-species crossing in tobacco.

Variation characteristics of the nitrate reductase gene of key inbred maize lines and derived lines in China

Key inbred lines have played a fundamental role in maize genetics and breeding. Research on variation characteristics of key genes from key inbred lines and from derived lines is important for early identification and evaluation of inbred maize lines. The nitrate reductase (NR) gene, which plays a central role in nitrate acquisition, was the target gene for this research. Forty-one inbred maize lines were investigated, including four key inbred lines: Huangzaosi, Mo17, Dan340, and Ye478. Through multiple sequence alignment with the NR gene from B73, used as a control, we found that: 1) the NR gene of most inbred lines from Huangzaosi and from derived lines had two insertion fragments and two replacement fragments; 2) the NR gene of most inbred lines from Mo17 and derived lines had one insertion fragment and one replacement fragment; 3) there were two common variations and eight common SNPs in the NR gene of the four key lines. Huangzaosi and Mo17 also had three common variations compared with the other key lines. Moreover, Mo17 had some unique variations; there were no unique variations in the other key lines, even for SNPs, and 4) phylogenetic tree analysis showed that the NR gene of the derived lines from the same key line had higher sequence homology. Based on the above NR gene variation characteristics and sequence homology of key inbred lines and derived lines, a candidate inbred line can be preliminarily selected and evaluated by marker development and/or sequence alignment of the NR gene.

Percutaneous Absorption of Captopril from Hydrophilic Cellulose Derivatives Through Excised Rabbit Skin and Human Skin

The purpose of this investigation was to evaluate the influence of percutaneous absorption of captopril from hydrophilic cellulose derivatives gel bases (carboxymethylcellulose sodium [CMC], hydroxypropylcellulose [HPC] and hydroxylpropylmethylcellulose [HPMC]. The effects of various types and concentrations of penetration enhancers on captopril percutaneous absorption from HPC gel through rabbit skin were evaluated and selected to obtain some optimal formulations for penetration study through human chest skin. Then the required flux (1488 microg/hr) for captopril transdermal drug delivery system to maintain the therapeutic minimum effective concentration through human skin was used to evaluate the development of the optimal formulations. The results indicated that the minimum administered areas for therapeutic minimum effective concentration of captopril (cap) gel containing decanol (dec) were 10.4 cm2 (5% cap, 7% dec) and 7.6 cm2 (7% cap, 7% dec). These areas were within acceptable range, so these formulations can possibly be developed for a transdermal drug delivery system.

Organogenesis of pancreatic anlagen allografted in rats

AIMS

To study the possibility of revascularization, growth, and differentiation of embryonic pancreatic anlagen transplanted to adult hosts. While transplantations of pancreas and islets are the main methods to cure diabetes mellitus, the donor source is in shortage. So it's necessary to find a new source for transplantation.

METHODS

The pancreas from embryonic day 14.5 (E14.5) and 15.5 (E15.5) Lewis rat embryos were implanted into either intraperitoneal or subrenal capsular site of healthy Lewis rats. at 3 weeks or 6 weeks after implantation, the pancreatic anlagen in the host rats were resected for size measurements, as well as histopathologic and immunohistochemical examinations.

RESULTS

Three weeks after implantation into the renal-capsular site, the size of both E14.5 and E15.5 pancreatic anlagen had enlarged 10- to 15-fold with differentiation of acinar components upon histological examination. Moreover, increasing numbers of beta cells and islets stained positive for insulin, and newly generated vessels were observed around the tissues. Continued proliferation of the endocrine islets in E14.5 pancreatic anlagen grafts was observed after another 3 weeks, whereas further proliferation in the E15.5 pancreatic anlagen graft was not seen. Additionally fibrosis appeared in the exocrine component of both E14.5 and E15.5 pancreatic anlagen at this time point. When implanted into intraperitoneal site, enlarged E15.5 pancreatic anlagen with proliferatels beta cells were also observed after 3 weeks. However, both the size of the pancreatic anlagen and the proliferation of the beta cells were much less than that in the subrenal capsular site.

CONCLUSIONS

The allografted E14.5 and E15.5 pancreatic anlagen revascularised and grew into tissues that were structurally similar to normal mature rats pancreatic tissue. Adequate embryonic age for the transplantation of pancreatic anlagen is 14.5 and 15.5 days old. Subrenal capsula is a more suitable site than the peritoneal cavity for implantation of pancreatic anlagen.

Induction of Accommodation Model by Combined RNA Interference Targeting 1,3-Galactosyltransferase Gene and Low-Dose GS-IB4 Lectin In Vitro

OBJECTIVE

This study sought to mimic the interaction of xenograft endothelial cells and human serum in vitro after successfully silencing the expression of porcine alpha1,3-galactosyltransferase (alpha1,3GT) gene by RNA interference (RNAi), and to investigate the possibility of inducing accommodation in vitro by stimulation of alpha-Gal-specific binding lectin, Griffonia simplicifolia isolectin B4 (GS-IB4) and RNAi.

MATERIALS AND METHODS

Various alpha-Gal expression patterns on a pig endothelial cell immortalized line (PED) was achieved by serial doses of small interfering RNA (siRNA) targeting porcinc alpha1,3GT gene. alpha1,3GT-siRNA transfected PEDs were exposed to increasing doses of GS-IB4 lectin (0.5, 2, and 8 microg/mL) for 4 hours before incubation with normal human serum (NHS). Accommodation phenomenon of PEDs in NHS was observed by 51Cr release and antibody/complement binding assays.

RESULTS

With combined RNAi and low-dose GS-IB4 stimulation, PEDs remarkably inhibited complement-mediated cytotoxicity, which showed a better protective effect than using RNAi alone. At a concentration of 2 mug/mL, GS-IB4 exhibited the maximum protective effect. The expression of E-selectin on alpha1,3GT-siRNA transfected PEDs did not differ from that on parental PEDs with heat-inactivated NHS (HINHS) stimulation. Combined with GS-IB4 stimulation, however, it inhibited expression of E-selectin, which was GS-IB4 dose dependent, resulting in mean fluorescence intensity values of 98.5, 42.0, and 36.3 at 0.5, 2, and 8 microg/mL. The mRNA expression of the protective gene HO-1 was significantly up-regulated after treatment with RNAi and low-dose of GS-IB4.

CONCLUSIONS

Combined RNAi and low-dose GS-IB4 induced pig endothelial cell accommodation in vitro. The level of alpha-Gal expression played an important role in the induction of accommodation.

Sertoli Cells Induce Xenolymphocyte Apoptosis In Vitro

BACKGROUND

Testicular Sertoli cells can protect pancreatic islet grafts from allo- and autoimmune destruction; however, the mechanisms underlying immune privilege of the testicle are not well understood, especially in xenotransplantation. The purpose of this study was to investigate whether rat Sertoli cells could induce mouse lymphocyte apoptosis in vitro.

METHODS

Testis was isolated from 2- to 4-week-old Sprague Dawley (SD) rats. Sertoli cells were successfully prepared by digestion with collagenase type V, trypsin, and DNase I, and then identified by electron microscope. Viability and apoptosis of cultured cells were measured by flow cytometry. We examined the apoptosis rates of Balb/c mouse lymphocytes, which were cocultured with SD rat Sertoli cells by FACS. The expression of Fas ligand (Fasl), transforming growth factor (TGF)-beta1 and clusterin on Sertoli cells were detected by immunocytochemistry.

RESULTS

In the cocultured system, Sertoli cells accounted for more than 93%. With our isolation method, the viability of Sertoli cells was more than 95% and the apoptosis rate was 10.87% +/- 3.87%. The lymphocyte apoptosis ratio was 15.52 +/- 0.17 (P < .01, compared with the control groups). SABC immunochemistry staining showed that the sertoli cells could express FasL, TGF-beta, and clusterin.

CONCLUSIONS

In our coculture in vitro, rat Sertoli cells expressed FasL and TGF-beta1 as well as induced the apoptosis of mouse lymphocytes. These results indicated that the expression of FasL and TGF-beta1 on Sertoli cells might relate to immune privilege in xenotransplantation.

Effects of the silanized mica surface on protein crystallization

A freshly cleaved mica surface silanized by 3-aminopropyl triethoxysilane is flat over a large area, displays a controlled degree of hydrophobicity and contains positive charges. In this paper, mica sheets silanized by this method have been used as crystallization surfaces for lysozyme, trichosanthin and three other proteins of unknown structure. Crystallization experiments have been carried out by the hanging-drop vapour-diffusion technique and the results indicate that the silanized mica surface can ameliorate the protein crystallization process considerably compared with a silanized glass cover slip control. For lysozyme on the silanized mica surface, the induction time required for crystal growth decreases markedly. For trichosanthin, the crystal size is obviously larger and the number of crystals grown is much lower. For the three proteins of unknown structure, the diffraction ability of the crystals is improved considerably.

Evaluation of percutaneous absorption and skin irritation of ketoprofen through rat skin: in vitro and in vivo study

The influences of different mechanisms of penetration enhancers (such as menthol, azone, ethanol and nonivarnide) regarding the percutaneous absorption and skin irritation of ketoprofen formulations through rat skin were investigated by in vitro and in vivo study. The skin irritation degree at the end of the experiment (10 h) was deterinined by pathologic biopsy and colorimetry methods. In vitro, the menthol showed the most potent enhancing effect. Furthermore, the enhancement effect of a combination of menthol and nonivamide was higher than that of their individual use alone. In vivo the formulation containing 0.05% nonivantide, 5% menthol and 20% ethanol showed a higher penetration rate and an acceptable degree of skin irritation compared to a commercial product (Formax plus gel containing 3% ketoprofen), indicating that it could be used in the clinical situation.

Influence of electrical and chemical factors on transdermal iontophoretic delivery of three diclofenac salts

The aim of this present study was to investigate the in vitro transdermal iontophoretic delivery of three diclofenac salts--diclofenac sodium (DFS), diclofenac potassium (DFP), and diclofenac diethylammonium (DFD). A series of physicochemical and electrical variables which might affect iontophoretic permeation of diclofenac salts was studied. Application of 0.3 mA/cm2 current density significantly increased the transdermal flux of diclofenac salts as compared to passive transport. The iontophoretic enhancement increased in the order of DFS>DFP>DFD. The permeability coefficient of diclofenac salts all decreased with increasing donor concentration during iontophoresis. The addition of buffer ions and salt ions such as NaCl, KCl, and C4H12ClN reduced the permeation of diclofenac salts due to competition. However, this effect was lesser for DFD than for DFS and DFP. Comparing the various application modes of iontophoresis, the discontinuous on/off mode showed lower but more constant flux than the continuous mode.

In vitro skin permeation of estradiol from various proniosome formulations

The skin permeation of estradiol from various proniosome gel formulations across excised rat skin was investigated in vitro. The encapsulation efficiency and size of niosomal vesicles formed from proniosomes upon hydration were also characterized. The encapsulation (%) of proniosomes with Span surfactants showed a very high value of about 100%. Proniosomes with Span 40 and Span 60 increased the permeation of estradiol across skin. Both penetration enhancer effect of non-ionic surfactant and vesicle-skin interaction may contribute to the mechanisms for proniosomes to enhance estradiol permeation. Niosome suspension (diluted proniosomal formulations) and proniosome gel showed different behavior in modulating transdermal delivery of estradiol across skin. Presence or absence of cholesterol in the lipid bilayers of vesicles did not reveal difference in encapsulation and permeation of the associated estradiol. The types and contents of non-ionic surfactant in proniosomes are important factors affecting the efficiency of transdermal estradiol delivery.

Evaluation of pharmacokinetics and pharmacodynamics of captopril from transdermal hydrophilic gels in normotensive rabbits and spontaneously hypertensive rats

The purpose of this investigation was to assess the pharmacokinetics (plasma concentration) and pharmacodynamics (heart rate, blood pressure (BP), and plasma renin activity (PRA)) of captopril experimental gel in normotensive rabbits and spontaneously hypertensive rats (SHRs) by reference to a short duration intravenous administration of the drug. In normotensive rabbits, the blood concentration versus time course of captopril after transdermal administration could be described well by a two-compartment model, and the maximum plasma concentration (5. 68+/-2.05 microg ml(-1)) was achieved in about 7 h. The increase in plasma captopril concentration led to increases in PRA and reductions in BP. A simple E(max) model adequately described the relationship between the percentage change of mean blood pressure (MBP) and the blood concentration of the captopril. The maximum reduction in MBP (E(max)) was 36.23% and the concentration at half maximum effect (EC(50)) was 0.24 microg ml(-1). The captopril was continuously released from the gel formulation and protected the SHRs in lower BP throughout the period of transdermal therapy. These results indicated that the development of captopril transdermal drug delivery system was possible. Further research was warranted on a modified formulation of captopril, which was optimized for transdermal delivery of the drug.

Hyperlipidemia of normal pregnancy in Karachi-Pakistan

During pregnancy, changes in the levels of total cholesterol, triglyceride, low density lipoprotein-cholesterol, and high density lipoprotein-cholesterol have been described, but in the existing literature these effects remain controversial because of inconsistencies. Moreover, the degree of change varies from study to study. Therefore, the present study completely investigated changes in lipids and lipoproteins throughout the pregnancy and in the puerperium. We also investigated whether or not any relation between plasma lipids and other pregnancy related factors exist. Concentrations of cholesterol and triglyceride of total plasma, and lipoproteins were determined in 56 pregnant women throughout the pregnancy and in the puerperium along with 56 non-pregnant women. Compared to control group, concentrations of cholesterol and triglyceride of total plasma and lipoproteins increased significantly during second trimester and reached maximum in the third trimester. Both cholesterol and triglyceride concentrations decreased significantly within 24 hours of delivery and this was reflected in all lipoproteins. In the majority of subjects, cholesterol and triglycerides remained significantly high until 4 weeks of postpartum. The magnitude of the serum cholesterol increment appeared in part to be related to that of serum triglyceride, but these increments appeared to be independent of age, weight gain, numbers of previous pregnancies and sex of the fetus. This study concludes that hyperlipidemia is a common finding during pregnancy.

In vitro study of transdermal nicotine delivery: influence of rate-controlling membranes and adhesives

The objective of this study was to evaluate the influence of a rate-controlling membrane and adhesive on the in vitro permeation of nicotine. The physicochemical properties of the adhesive, including adhesion and rheology (viscosity), were also detected. Higher permeability of nicotine was observed through a hydrophilic membrane than through a hydrophobic membrane. Natural rubber and silicone were used as the adhesive bases, respectively. The silicone adhesive showed the highest adhesion among all adhesive formulations. To increase the adhesion of natural rubber, a tackifier (polyisoprene) and a secondary tackifier (terpene polymer; Px 1150) were incorporated into the formulations to achieve acceptable adhesion. The nicotine permeation through silicone adhesive and three natural rubber adhesives with the secondary tackifier (2%, 4%, and 6% Px 1150) was close to that from a commercially available patch (Habitrol), although the loading amount of nicotine was not the same. A longer lag time during the in vitro permeation study of nicotine was required for the adhesives prepared in our laboratory than for the commercially available patch.

Cyclic monoterpene extract from cardamom oil as a skin permeation enhancer for indomethacin: in vitro and in vivo studies

The in vitro and in vivo effect of pretreatment by cardamom oil, a crude drug extract, in ethanol/water vehicles on the transdermal delivery of indomethacin was investigated. The cyclic monoterpene components in cardamom oil were also determined and quantified in this study. The permeation of indomethacin was significantly enhanced after pretreatment of cardamom oil both in the in vitro and in vivo studies. The result of various pre-treatment periods showed that the indomethacin flux decreased as the length of the pretreatment increased. Both natural cardamom oil and a cyclic monoterpene mixture composed of the components of the oil showed similar enhancement on indomethacin permeation, indicating cyclic monoterpenes are the predominant components altering the barrier property of stratum corneum. The results also showed that three minor components in cardamom oil (alpha-pinene, 6.5%; beta-pinene, 4.8%; alpha-terpineol, 0.4%) had a synergistic effect with 1,8-cineole (59.3%) and d-limonene (29.0%) to enhance the permeation of indomethacin.

Evaluation of transdermal iontophoresis of enoxacin from polymer formulations: in vitro skin permeation and in vivo microdialysis using Wistar rat as an animal model

Polymers were used in vehicles to form hydrogel matrices in this study to evaluate the in vitro permeation and in vivo microdialysis of enoxacin. The highest transdermal delivery determined by area under flux-time curve (AUC) and intracutaneous enoxacin concentration were observed in methylcellulose (MC) and polyvinylpyrrolidone (PVP) hydrogels, respectively. To avoid the pH shift in vehicles during iontophoresis, buffer species were added to formulations to increase the buffer capacity. As expected, the permeability of enoxacin of anodal iontophoresis was larger than that of cathodal iontophoresis. Combination of benzalkonium chloride, a cationic surfactant as an enhancer, and iontophoresis exerted an enhancing effect for anionic enoxacin at pH 10.0. However, no effect or a negative effect was detected for cationic enoxacin in deionized water or pH 5.0 buffer, due to the shielding of the negative charge in the skin. The skin residue of enoxacin was slightly increased after the incorporation of Azone in PVP hydrogel. The result of in vivo microdialysis was in accordance with that of in vitro study. The effect of Azone on the intracutaneous enoxacin was more significant for in vivo microdialysis than in the in vitro study indicating the clinical feasibility of Azone for iontophoretic delivery. Microdialysis can be considered as a useful technique to investigate the pharmacokinetics of transdermal iontophoresis in vivo.

Evaluation of topical application of clobetasol 17-propionate from various cream bases

The effect of clobetasol 17-propionate (CP), a potent corticosteroid, in various cream bases on the permeation through artificial membrane was sought. Four formulations were then chosen for a further in vivo skin blanching assay. After calculation of the relationship between in vivo flux0-8 hr determined from a surface recovery technique and in vitro release rate0-8 hr of CP from various formulations, a high correlation coefficient of 0.9996 was achieved. Therefore, the in vitro release study could be used as an index to predict and evaluate the in vivo penetration capacity of CP cream to screen the effective formulation preclinically. After a series of in vivo investigations in this study, it was concluded that myristic acid-added formulations may show a bioequivalence with commercial Dermovate. Furthermore, the flux calculated from the surface recovery technique and delta E detected from the skin blanching assay may be useful as parameters evaluating the quality and effectiveness of CP cream.

Transdermal delivery of sodium nonivamide propionate by iontophoresis

The aim of this study was to investigate the transdermal iontophoresis of a newly designed capsaicin derivative, sodium nonivamide propionate (SNP). The iontophoretic permeation of SNP from various pH buffers increased following the decrease of pH values. This trend was consistent with that of sodium nonivamide acetate (SNA) which is another synthetic analogue of capsaicin. However, the iontophoretic permeability of SNP was much lower than that of SNA. SNP was also delivered iontophoretically from hydrogel formulations. It is suggested that ionizable polymers should be avoided for iontophoretic delivery to maintain good penetration capacity of drugs. Both nonionic cellulose polymers of methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC) showed higher iontophoretic flux for SNP than the others did. Furthermore, the flux of SNP leveled off with an increase in the amount of polymers in hydrogel, indicating that the viscosity of vehicles plays an important role in the permeation of SNP. Comparing the various iontophoretic application modes, the discontinuous on/off cyclic mode showed higher penetration capacity than did the continuous mode although they possessed the same electrical energy. Moreover, the desorption time of SNP from skin was approximately 20 min which was longer than that of SNA.

Topical application of clobetasol 17-propionate from various cream bases by using Wistar rat as an animal model

The effect of clobetasol 17-propionate (CP), a potent corticosteroid, participating in various cream bases on the permeation through rat skin was tested in vitro. Three commercially available formulations and three cream bases prepared in our laboratory according to Pharmacopoeia or registered patent were evaluated in this present study. The amount of CP in the receptor phase of diffusion cell was negligible in the beginning of administration due to the process of saturation of drug in skin reservoir, then the CP molecules pass through the skin directly because of the saturation of receptors in skin reservoir followed the higher flux of CP in the later period. It was suggested that the incorporation of penetration enhancers was the possible reason mainly controlling the flux of CP creams. Nevertheless, CP residue in skin and the lag time of formulations prepared in our laboratory were not significantly higher than those of commercial ones, which indicated penetration enhancer could not dominate the local pharmacological effectiveness of CP though they played a main part on the skin penetration capacity of formulations. The antiinflammatory activity of CP was assessed in the ear of Wistar rat. According to the result of antiinflammatory activity, all formulations showed significant inhibition on oedema suggesting the role of drug itself may be more important than that of vehicle in controlling the therapy efficacy.