[Historical review of schistosomiasis prevention and treatment in southern Anhui from 1950 to 1970]

From 1950 to 1970, under the leadership of the central government, workstations for the prevention and control of schistosomiasis were established in the southern Anhui region. In terms of controlling the source of the disease, light and severe epidemic areas were scientifically divided. By opening new ditches to replace old ones, changing paddy fields to dry fields, and using traditional Chinese medicine and Western medicine to prevent the intermediate host of schistosomiasis, oncomelania from surviving. By managing the feces from human and animals and controlling the water source, the transmission route of schistosome eggs has been effectively cut off. At the same time, the education of hygiene awareness among susceptible populations were strengthened. In terms of diagnosis, modern physical and biochemical detection were used to improve the accuracy of diagnosis. In terms of treatment, by combining traditional Chinese medicine and Western medicine, together with the splenectomy, the cure rates were improved. In the process of preventing and controlling schistosomiasis, the governments of Anhui Province and the southern region of Anhui Province achieved good results, providing useful reference for the prevention and control of other diseases.

[Comparison of the effects and safety of dydrogesterone and medroxyprogesterone acetate on endometrial hyperplasia without atypia: a randomized controlled non-inferior phase Ⅲ clinical study]

Objective: To compare the effects and safety of dydrogesterone (DG) and medroxyprogesterone acetate (MPA) on the treatment in patients with endometrial hyperplasia without atypia (EH). Methods: This was a single-center, open-label, prospective non-inferior randomized controlled phase Ⅲ trial. From February 2019 to November 2021, patients with EH admitted to the Obstetrics and Gynecology Hospital of Fudan University were recruited. Enrolled patients were stratified according to the pathological types of simple hyperplasia (SH) or complex hyperplasia (CH), and were randomised to receive MPA or DG. Untill May 14, 2022, the median follow-up time after complete response (CR) was 9.3 months (1.1-17.2 months). The primary endpoint was the 6-month CR rate (6m-CR rate). The secondary endpoints included the 3-month CR rate (3m-CR rate), adverse events rate, recurrence rate, and pregnancy rate in one year after CR. Results: (1) A total of 292 patients with EH were enrolled in the study with the median age of 39 years (31-45 years). A total of 135 SH patients were randomly assigned to MPA group (n=67) and DG group (n=68), and 157 CH patients were randomly assigned to MPA group (n=79) and DG group (n=78). (2) Among 292 patients, 205 patients enrolled into the primary endpoint analysis, including 92 SH patients and 113 CH patients, with 100 patients in MPA group and 105 in DG group, respectively. The 6m-CR rate of MPA group and DG group were 90.0% (90/100) and 88.6% (93/105) respectively, and there were no statistical significance (χ²=0.11, P=0.741), with the rate difference (RD) was -1.4% (95%CI:-9.9%-7.0%). Stratified by the pathology types, the 6m-CR rate of SH patients was 93.5% (86/92), and MPA group and DG group were respectively 91.1% (41/45) and 95.7% (45/47); and the 6m-CR rate of CH patients was 85.8% (97/113), and MPA group and DG group were 89.1% (49/55) and 82.8% (48/58) respectively. The 6m-CR rates of the two treatments had no statistical significance either (all P>0.05). A total of 194 EH patients enrolled into the secondary endpoint analysis, including 88 SH patients and 106 CH patients, and 96 patients in MPA group and 98 in DG group, respectively. The 3m-CR rate of SH patients were 87.5% (77/88), while the 3m-CR rates of MPA group and DG group were 90.7% (39/43) and 84.4% (38/45), respectively; the 3m-CR rate of CH patients was 66.0% (70/106), and MPA group and DG group had the same 3m-CR rate of 66.0% (35/53). No statistical significance was found between the two treatments both in SH and CH patients (all P>0.05). (3) The incidence of adverse events between MPA group and DG group had no statistical significance (P>0.05). (4) A total of 93 SH patients achieved CR, and the cumulative recurrence rate in one year after CR were 5.9% and 0 in MPA group and DG group, respectively. While 112 CH patients achieved CR, and the cumulative recurrence rate in one year after CR were 8.8% and 6.5% in MPA group and DG group, respectively. There were no statistical significance between two treatment groups (all P>0.05). Among the 93 SH patients, 10 patients had family planning but no pregnancy happened during the follow-up period. Among the 112 CH patients, 21 were actively preparing for pregnancy, and the pregnancy rate and live-birth rate in one year after CR in MPA group were 7/9 and 2/7, while in DG group were respectively 4/12 and 2/4, and there were no statistical significance in pregnancy rate and live-birth rate between the two treatment groups (all P>0.05). Conclusions: Compared with MPA, DG is of good efficacy and safety in treating EH. DG is a favorable alternative treatment for EH patients.

[Mechanism of intestinal injury induced by WNT2B high-expressed fibroblasts in Crohn's disease]

Objective: To explore the mechanism of intestinal tissue damage induced by macrophages activated by WNT2B high-expressed fibroblasts. Methods: This study involved biological information analysis, pathological tissue research and cell experimental research. The biological information of the colon tissue from the children with inflammatory bowel disease in previous study was analyzed again with single-cell sequencing. The pathological tissues were collected by colonoscopy from 10 children with Crohn's disease treated in the Department of Gastroenterology of Guangzhou Women and Children's Medical Center from July 2022 to September 2022. According to the findings of colonoscopy, tissues with obvious inflammation or ulceration were classified as the inflammatory group, while tissues with slight inflammation and no ulceration were classified as the non-inflammatory group. HE staining was performed to observe the pathological changes of the colon tissues. Macrophage infiltration and CXCL12 expression were detected by immunofluorescence. In terms of cell experiments, fibroblasts transfected with WNT2B plasmid or empty plasmid were co-cultured with salinomycin treated or non-treated macrophages, respectively; the expression of proteins through Wnt classical pathway were detected by western blotting. Macrophages treated with SKL2001 were used as the experimental group, and those with phosphate buffer as the control group. The expression and secretion of CXCL12 in macrophages were detected by quantitative Real-time PCR and enzyme-linked immunosorbent assay (ELISA). T-test or rank sum test were used for the comparison between groups. Results: Single-cell sequencing analysis suggested that macrophages were the main cells in inflammatory bowel disease colon tissue, and there was interaction between WNT2B high-expressed fibroblasts and macrophages. HE staining of the 10 patients ((9.3±3.8) years old, 7 males and 3 females) showed that the pathological score of colon tissue in the inflammatory group was higher than that in the non-inflammatory group (4 (3, 4) vs. 2 (1, 2) points, Z=3.05, P=0.002). Tissue immunofluorescence indicated that the number of infiltrating macrophages in the inflammatory group was significantly higher than that in the non-inflammatory group under high power field of view (72.8±10.4 vs.8.4±3.5, t=25.10, P<0.001), as well as the number of cells expressing CXCL12 (14.0±3.5 vs. 4.7±1.9, t=14.68, P<0.001). In cell experiments, western blotting suggested an elevated level of glycogen synthase kinase-3β phosphorylation in macrophages co-cultured with fibroblast transfected with WNT2B plasmid, and salinmycin could reverse this change. Real-time PCR suggested that the transcription level of CXCL12 in the experimental group was higher than that in the control group (6.42±0.04 vs. 1.00±0.03, t=183.00, P<0.001), as well as the expression and secretion of CXCL12 by ELISA ((465±34) vs. (77±9) ng/L, t=13.21, P=0.006). Conclusion: WNT2B high-expressed fibroblasts can secrete WNT2B protein and activate the Wnt classical signaling pathway thus enhancing the expression and secretion of CXCL12 in macrophages, inducing the development of intestinal inflammation of Crohn's disease.

Fat mass as an important predictor of persistent hypertension in patients with primary aldosteronism after adrenalectomy

Aldosterone excess is present in obesity and is associated with involvement in the pathogenesis of obesity. We evaluate the impact of body obesity as measured by body composition monitor (BCM) on clinical outcomes in patients with unilateral primary aldosteronism (uPA) after adrenalectomy. The BCM device was used to assess body composition before and after adrenalectomy. We used fat mass (FM) and body mass index (BMI) to classify obesity and divided obesity into three groups: clinical overweight (BMI (kg/m2) ≥25); normal weight obesity (NWO, FM (%) ≥ 35 for women, >25 for men & BMI < 25); and no obesity (FM < 35 for women, <25 for men & BMI < 25). A total of 130 unilateral PA (uPA) patients received adrenalectomy, and 27 EH patients were identified; uPA patients with hypertension remission were found to have lower FM (p = 0.046), BMI (p < 0.001), and lower prevalence of overweight (p = 0.001). In the logistic regression model, patients with clinical overweight (OR = 2.9, p = 0.007), NWO (OR = 3.04, p = 0.041) and longer HTN duration (years, OR = 1.065, p = 0.013) were at the risk of persistent hypertension after adrenalectomy. Obesity status was strongly associated with persistent hypertension in uPA patients after adrenalectomy. However, patients in the NWO group also carried higher risk of persistent hypertension. Therefore, assessment of pre-obesity and overweight in uPA patients are extremely important, especially in those who have normal BMI.

[A death case of oral lime sulfur mixture poisoning]

The Second Affiliated Hospital of Shandong First Medical University treated a patient with oral sulfur mixture poisoning on January 14, 2020. The patient presented with cyanosis and disturbance of consciousness as the first manifestations, accompanied by metabolic acidosis, shock, hypercalcemia and severe liver function and myocardial damage. The patient was given active treatment, including gastric lavage, blood purification, methylene blue application, correction of shock, organ support and other therapies. However the treatment was poor. Finally, the patient's family chose to give up and requested to be discharged from the hospital, and the patient died on the same day after follow-up.

[Clinical characteristics of heart failure with recovered ejection fraction]

Objective: To summarize the clinical characteristics of heart failure patients with recovered ejection fraction (HFrecEF) and identify variables capable of predicting left ventricular ejection fraction (LVEF) recovery. Methods: This case control study included patients with heart failure, who admitted to Department of Cardiology of Beijing Hospital from January 1, 2009 to December 31, 2017. The patients were divided into 3 groups based on the baseline LVEF and changes of LVEF: heart failure with reduced ejection fraction (HFrEF, baseline LVEF≤40%, follow-up LVEF≤40% or follow-up LVEF>40% but LVEF increase<10% from baseline), HFrecEF(baseline LVEF≤40%, follow-up LVEF>40% and increase≥10% from baseline), and heart failure with preserved ejection fraction (HFpEF, baseline LVEF>40%). Clinical data were collected and endpoint events (all-cause death, cardiovascular death and sudden death) were recorded. The Log-rank test was used to evaluate the differences of terminal events in different groups, and Kaplan-Meier survival analysis was performed. Logistic regression equation was used to identify prognostic factors of HFrecEF. Results: A total of 310 patients with heart failure were included. There were 91(29.4%) HFrEF patients, 38(12.3%) HFrecEF patients and 181(58.4%) HFpEF patients. Compared with HFrEF patients and HFpEF patients, HFrecEF patients were featured by younger age, more likely to be female, higher systolic blood pressure, diastolic blood pressure and resting heart rate (all P<0.05). Dilated cardiomyopathies were more common, while old myocardial infarctions were less common in HFrecEF (both P<0.05). During a median follow-up of 36.7(18.0, 63.9) months, Kaplan-Meier survival analysis found that HFrecEF patients had the lowest all-cause mortality (Log-rank P=0.047, HFrecEF vs. HFpEF P=0.017, HFrecEF vs. HFrEF P=0.016, and HFpEF vs. HFrEF P=0.782).The cardiovascular mortality ranged from low to high was in HFrecEF patients, HFpEF patients, and HFrEF patients (Log-rank P<0.001, HFrecEF vs. HFpEF P=0.029, HFrecEF vs. HFrEF P<0.001, HFrEF vs. HFpEF P=0.005). Sudden death rate was similar among the three groups (Log-rank P=0.520). Logistic regression analysis showed that left ventricular end-diastolic diameter (LVEDD)≤55 mm (OR=5.922, 95%CI 1.685-20.812, P=0.006), higher diastolic blood pressure (OR=1.058, 95%CI 1.017-1.100, P=0.005), faster resting heart rate (OR=1.042, 95%CI 1.006-1.080, P=0.024), absence of old myocardial infarction (OR=5.343, 95%CI 1.731-16.488, P=0.004) were independent prognostic factors of LVEF recovery after clinical treatment. Conclusions: Patients with HFrecEF are associated with a better prognosis as compared to patients with HFrEF and HFpEF. LVEDD≤55 mm, higher diastolic blood pressure, faster heart rate,and absence of old myocardial infarction are independent prognostic factors of LVEF recovery after clinical treatment.

[The discussion of the correlation between tumor necrosis factor-alpha and aquaporin 4 expression in critical poisoning brain edema]

Critical poisoning is a critical illness. Cerebral edema after poisoning is one of the important factors that cause the patient's condition to worsen and affect the prognosis of patients after acute brain injury. Aquaporin 4 (AQP-4) is an important member of the aquaporin family and is abundantly expressed in the central nervous system, playing a pivotal role in the formation of cerebral edema. Brain injury can cause the secretion of inflammatory transmitters, causing or aggravating cerebral edema. Tumor necrosis factor-alpha (TNF-α) has been confirmed to be most closely related to cerebral edema, and can participate in the formation and development of brain edema by regulating AQP-4.

[Investigation on the awareness of snoring hazard and prevalence of obstructive sleep apnea among civil servants]

Objective: To investigate the awareness of snoring hazard and prevalence of obstructive sleep apnea (OSA) among civil servants. Methods: A cross-sectional survey was conducted to investigate the awareness of snoring hazards among in-service civil servants who had annual medical examination in a Guangdong provincial institution from September to November 2017. The high-risk group for OSA was screened and diagnosed by sleep monitoring. Results: 1 036 of 1 241 civil servants were enrolled in the study for integral data. 60.1% (623/1 036) of the subjects realized that snoring was harmful to health. The most common source to develop OSA awareness was network (59.6%, 371/623), followed by television (48.0%), relatives and friends (46.6%), newspaper (44.5%) and radio (18.9%). The awareness rate of snoring consequences was as follows: decreased sleep quality (71.9%, 448/623), sudden death (52.2%), daytime sleepiness (44.3%), cardiovascular and cerebrovascular diseases (42.9%), hypertension (24.4%) and sexual dysfunction (16.7%). 22.0% (228 / 1 036) of the cases were classified into high-risk OSA. The prevalence of OSA among high-risk group was 46.05%(105/228)and only 0.9% (2/228) of them had been diagnosed with OSA. Conclusion: Civil servants had awareness of snoring hazard to a certain extent. Among civil servants classified into high-risk OSA, the OSA perveance was high but the rate of diagnosis and treatment was very low.

[Citrate anticoagulation hemoperfusion in the treatment of 273 patients]

Early hemoperfusion in poisoned patients can remove poisons rapidly and effectively, which plays an important role in improving the prognosis of patients. The key of hemoperfusion therapy is the safe and effective anticoagulation. The local citrate anticoagulation effect acid is good, it also has little effect on the systemic coagulation mechanism and internal environment of patients, so it is worthy of promotion. We retrospectively analyzed the clinical data and treatment of 273 patients who were poisoned by citrate anticoagulant in the emergency intensive care unit of the Second Affiliated Hospital of Shandong First Medical University, aiming at perfusion of citrate anticoagulant in patients with poisoning. Provide a certain clinical reference.

[Structural equation model analysis of infectious disease-specific health literacy scale in China]

Objective: To explore the relationship between different dimensions of infectious disease-specific health literacy scale in China. Methods: Structural equation model (SEM) was employed to assess the psychometric properties of the infectious disease-specific health literacy scale. Based on the database from a randomly selected sample of 4 499 adult residents in three provinces in China, from March to May 2015. AMOS 21.0 software was used to build the SEM for data analyses. Results: SEM analyses showed a good model fit of data, with the following satisfied parameters: goodness-of-fit index was 0.969, adjusted goodness-of-fit index was 0.962, root mean square residual was 0.038, root mean square error of approximation was 0.038, standardized root mean square residual was 0.032, Tacker-Lewis index/non-normed fit index was 0.926, comparative fit index was 0.934, normed fit index was 0.925, relative fit index was 0.915, incremental fit index was 0.934, parsimony goodness-of-fit index was 0.782, parsimony-adjusted normed fit index was 0.817, parsimony-adjusted comparative fit index was 0.825 and critical N was 702. The established SEM showed that the total influence path coefficient of "infectious disease-related knowledge and values" on the "infectious disease prevention" , "management or treatment of infectious diseases" and "identification of infection sources" were 0.771, 0.744 and 0.843, respectively. The total influence path coefficients of "identification of infection sources" , "infectious disease prevention" on "management or treatment of infectious diseases" were 0.164 and 0.535, respectively. The effect of "infectious disease-related knowledge and values" on "management or treatment of infectious diseases" appeared the greatest (55.4%), followed by "infectious disease prevention" (28.6%) and "identification of infection sources" (2.7%). Conclusion: This SEM could be optimistically used for planning and evaluation of health education and promotion programs on infectious diseases prevention.

Band Tunable Microcavity Perovskite Artificial Human Photoreceptors

Electronic device versions of the neural functions of the human retina have high potential for use in artificial vision. This study demonstrates halide perovskite artificial human photoreceptors with specific photoresponses to red, green, and blue colors, which are consistent with human retinal photoreceiving cones and rods. In contrast to the current programmable spectral-response technologies, a novel microcavity structure is combined in this study with a perovskite absorber to achieve a targeted spectrum without using external optical filters. The fabricated artificial photoreceptors exhibit excellent performance including a high detectivity of more than 10¹³ Jones, a large linear dynamic range of 154 dB, and a short response time of 580 ns. These values are equal to or better than those of the natural human retina. These devices can easily be monolithically integrated on a single flexible substrate by using vacuum deposition, and a true proof-of-concept full-color image reconstruction is demonstrated.

Prognostic Comparison of the Estimations of Renal Function in Patients With Acute Heart Failure

BACKGROUND

The prognostic significance of the eGFR calculated by either the four-level Race Chronic Kidney Disease-Epidemiology Collaboration study equation (CKD-EPI4R) or the Chinese-modified Modification of Diet in Renal Disease equation (cMDRD) has not been compared in Asian populations with acute heart failure (AHF).Methods and Results:A total of 3,044 patients hospitalized for AHF were enrolled. The National Death Registry was linked to identify deaths within a 5-year follow-up. Net reclassification improvement (NRI) was calculated to compare the prognostic value of either eGFR equation. During a median follow-up of 23.3 months, 1,424 (47%) patients died. Both eGFR_cMDRDand eGFR_CKD-EPI4Rwere independently predictive of death in the total study population (hazard ratio and 95% confidence intervals per 1-SD: 0.76, 0.71-0.81 and 0.74, 0.70-0.79, respectively), and in the subgroups of either reduced (HFrEF) or preserved (HFpEF) ejection fraction, after accounting for important confounders. With reference to eGFR_cMDRD, eGFR_CKD-EPI4Rmay improve the NRI by 2.0% (0.8-3.2%) for the prediction of death. The prognostic value of the CKD stages categorized by eGFR_CKD-EPI4Rsignificantly outperformed eGFR_cMDRDwith a categorical NRI of 9.5% (4.7-14.3%) in the total study population, 11.5% in HFrEF, and 8.3% in HFpEF.

CONCLUSIONS

Both eGFR_cMDRDand eGFR_CKD-EPI4Rwere independently associated with long-term survival in patients with AHF. However, the CKD stages derived from eGFR_CKD-EPI4Rimproved the risk stratification of death, compared with eGFR_cMDRD.

[Clinical effect of combined artificial extracorporeal liver support therapy for toxic hepatic failure]

Objective: To investigate the clinical effect of plasma exchange (PE) versus double plasma molecular adsorption system combined with PE (DPMAS+PE) in the treatment of toxic hepatic failure. Methods: A total of 67 patients with toxic hepatic failure who were admitted during the same period of time were divided into PE group, DPMAS+ PE group, and control group. The 22 patients in the PE group were treated with PE alone, and the 24 patients in the DPMAS+PE group were given DPMAS combined with PE. The clinical out-come was compared between the three groups. Results: Both treatment groups had significantly higher clinical response rate and 24-week survival rate than the control group. After treatment, both treatment groups had significant reductions in the serum levels of total bilirubin (TBil) , direct bilirubin (DBil) , alanine aminotransfer-ase (ALT) , and aspartate aminotransferase (AST) , and the PE group had significant reductions in the albumin (Alb) level and activated partial thromboplastin time (APTT) (P<0.05) ; the DPMAS+PE group showed no sig-nificant changes in the Alb level and APTT (P>0.05). There were no significant differences in TBil, DBil, ALT, and AST between the two treatment groups after treatment (P>0.05). After treatment, the PE group had significantly higher Alb level and APTT than the DPMAS + PE group (P<0.05). Compared with the control group, both treatment groups had significant reductions in TBil, DBil, ALT and AST after treatment (P<0.05). Conclusion: The two artificial liver support techniques can significantly improve patients' liver function and in-crease their survival rate, and the combined artificial liver support technique can reduce the amount of plasma used.

Fabrication of Nanoporous IrO₂/Ir Films for Bioelectrode and Neural Prosthesis Applications

IrO₂ and Ir are attractive materials for bio-interface applications due to their desirable stability, electrochemical performance, and biocompatibility. Nanostructured IrO₂/Ir possesses several advantageous properties including large surface-to-volume ratio, light weight, super hydrophilic surface, desirable electrochemical capability, and cell adhesion. Herein, we employ a cost-effective process to fabricate uniform nanoporous IrO₂/Ir film by chemical bath deposition, high-vacuum annealing, and electrochemical activation. High-vacuum annealing can remove oxygen from an IrO₂ film to create a nanoporous structure, and we determine the optimized electrochemical activation to transform Ir to IrO₂/Ir. The surface morphology, roughness, hydrophilicity, crystallinity, oxidation state, and charge storage capacity (CSC) of the films were analyzed. The nanoporous IrO₂/Ir film showed a 25% increase of CSC compared to the dense IrO₂ film, and this excellent performance makes it a promising candidate for bio-interface applications. In addition, this fabrication route can be cost-effective process without wasting the expensive noble metal Ir material.

Prognostic Nutritional Index and the Risk of Mortality in Patients With Acute Heart Failure

Background

Nutritional status has been related to clinical outcomes in patients with heart failure. We assessed the association between nutritional status, indexed by prognostic nutritional index (PNI), and survival in patients hospitalized for acute heart failure.

Methods and Results

A total of 1673 patients (age 76±13 years, 68% men) hospitalized for acute heart failure in a tertiary medical center were analyzed. PNI was calculated as 10×serum albumin (g/dL)+0.005×total lymphocyte count (per mm³). National Death Registry was linked to identify the clinical outcomes of all‐cause and cardiovascular death. With increasing tertiles of PNI, age and N‐terminal probrain natriuretic peptide decreased, and body mass index, estimated glomerular filtration rate, and hemoglobin increased. During a mean follow‐up duration of 31.5 months, a higher PNI tertile was related to better survival free from all‐cause and cardiovascular mortality in the total study population and in participants with either reduced or preserved left ventricular ejection fraction. After accounting for age, sex, estimated glomerular filtration rate, left ventricular ejection fraction, serum sodium level, and on‐admission systolic blood pressure, PNI was independently associated with cardiovascular death and total mortality (hazard ratio per 1 SD of the natural logarithm of the PNI: 0.76 [95% CI, 0.66–0.87] and 0.79 [95% CI, 0.73–0.87], respectively). In subgroup analyses stratified by age, sex, left ventricular ejection fraction, body mass index, or estimated glomerular filtration rate, PNI was consistently related to mortality.

Conclusions

PNI is independently associated with long‐term survival in patients hospitalized for acute heart failure with either reduced or preserved left ventricular ejection fraction.

Surface Degradation and Nanoparticle Release of a Commercial Nanosilica/Polyurethane Coating Under UV Exposure

Many coatings properties such as mechanical, electrical, and ultra violet (UV) resistance are greatly enhanced by the addition of nanoparticles, which can potentially increase the use of nanocoatings for many outdoor applications. However, because polymers used in all coatings are susceptible to degradation by weathering, nanoparticles in a coating may be brought to the surface and released into the environment during the life cycle of a nanocoating. Therefore, the goal of this study is to investigate the process and mechanism of surface degradation and potential particle release from a commercial nanosilica/polyurethane coating under accelerated UV exposure. Recent research at the National Institute of Standards and Technology (NIST) has shown that the matrix in an epoxy nanocomposite undergoes photodegradation during exposure to UV radiation, resulting in surface accumulation of nanoparticles and subsequent release from the composite. In this study, specimens of a commercial polyurethane (PU) coating, to which a 5 mass % surface treated silica nanoparticles solution was added, were exposed to well-controlled, accelerated UV environments. The nanocoating surface morphological changes and surface accumulation of nanoparticles as a function of UV exposure were measured, along with chemical change and mass loss using a variety of techniques. Particles from the surface of the coating were collected using a simulated rain process developed at NIST, and the collected runoff specimens were measured using inductively coupled plasma-optical emission spectroscopy (ICP-OES) to determine the amount of silicon released from the nanocoatings. The results demonstrated that the added silica nanoparticle solution decreased the photodegradation rate (i.e., stabilization) of the commercial PU nanocoating. Although the degradation was slower than the previous nanosilica epoxy model system, the degradation of the PU matrix resulted in accumulation of silica nanoparticles on the nanocoating surface and release to the environment by simulated rain. These experimental data are valuable for developing models to predict the long-term release of nanosilica from commercial PU nanocoatings used outdoors and, therefore, are essential for assessing the health and environmental risks during the service life of exterior PU nanocoatings.

Hyponatremia and Worsening Sodium Levels Are Associated With Long-Term Outcome in Patients Hospitalized for Acute Heart Failure

Background

Hyponatremia predicts poor prognosis in patients with acute heart failure (AHF). However, the association of the severity of hyponatremia and changes of serum sodium levels with long‐term outcome has not been delineated.

Methods and Results

The study population was drawn from the HARVEST registry (Heart Failure Registry of Taipei Veterans General Hospital), so that patients hospitalized for acute heart failure (AHF) composed this study. The National Death Registry was linked to identify the clinical outcomes of all‐cause mortality and cardiovascular death, with a follow‐up duration of up to 4 years. Among a total of 2556 patients (76.4 years of age, 67% men), 360 had on‐admission hyponatremia, defined as a serum sodium level of <135 mEq/L on the first day of hospitalization. On‐admission hyponatremia was a predictor for all‐cause mortality (hazard ratio and 95% CI: 1.43, 1.11–1.83) and cardiovascular mortality (1.50, 1.04–2.17), independent of age, sex, hematocrit, estimated glomerular filtration rate, left ventricular ejection fraction, and prescribed medications. Subjects with severe hyponatremia (<125 mEq/L) would even have worse clinical outcomes. During hospitalization, a drop of sodium levels of >3 mEq/L was associated with a marked increase of mortality than those with minimal or no drop of sodium levels. In addition, subjects with on‐admission hyponatremia and drops of serum sodium levels during hospitalization had an incremental risk of death (2.26, 1.36–3.74), relative to those with normonatremia at admission and no treatment‐related drop of serum sodium level in the fully adjusted model.

Conclusions

On‐admission hyponatremia is an independent predictor for long‐term outcomes in patients hospitalized for AHF. Combined the on‐admission hyponatremia with drops of serum sodium levels during hospitalization may make a better risk assessment in AHF patients.

Computational modeling of intraocular gas dynamics

The purpose of this study was to develop a computational model to simulate the dynamics of intraocular gas behavior in pneumatic retinopexy (PR) procedure. The presented model predicted intraocular gas volume at any time and determined the tolerance angle within which a patient can maneuver and still gas completely covers the tear(s). Computational fluid dynamics calculations were conducted to describe PR procedure. The geometrical model was constructed based on the rabbit and human eye dimensions. SF6 in the form of pure and diluted with air was considered as the injected gas. The presented results indicated that the composition of the injected gas affected the gas absorption rate and gas volume. After injection of pure SF6, the bubble expanded to 2.3 times of its initial volume during the first 23 h, but when diluted SF6 was used, no significant expansion was observed. Also, head positioning for the treatment of retinal tear influenced the rate of gas absorption. Moreover, the determined tolerance angle depended on the bubble and tear size. More bubble expansion and smaller retinal tear caused greater tolerance angle. For example, after 23 h, for the tear size of 2 mm the tolerance angle of using pure SF6 is 1.4 times more than that of using diluted SF6 with 80% air. Composition of the injected gas and conditions of the tear in PR may dramatically affect the gas absorption rate and gas volume. Quantifying these effects helps to predict the tolerance angle and improve treatment efficiency.

Determinants and Prognostic Impact of Hyperuricemia in Hospitalization for Acute Heart Failure

BACKGROUND

Hyperuricemia is a prognostic factor in patients with chronic heart failure, but whether uric acid level can predict clinical outcome of acute heart failure (AHF) remains to be elucidated. We therefore investigated the association of uric acid with mortality in patients hospitalized for AHF.

METHODS AND RESULTS

Data for patients hospitalized for AHF were drawn from an intramural registry. Biochemistry data, echocardiographic characteristics, and uric acid level were collected. National Death Registry was linked for the identification of mortality data. Among a total of 1,835 participants (age, 75 ± 13 years, 68% men), 794 patients died during follow-up. Patients who died were older, had lower hemoglobin and estimated glomerular filtration rate, and higher pulmonary artery systolic pressure, NT-proBNP, and uric acid. Uric acid was a significant predictor of mortality on univariate analysis (HR per 1 SD, 1.18; 95% CI: 1.11-1.26) and in multivariate Cox models (HR, 1.15; 95% CI: 1.02-1.29). Survival analysis showed an increasing risk of death along the quartile distribution of uric acid level. Given renal function, cardiac performance, and kidney perfusion as major determinants of hyperuricemia, the prognostic impact of uric acid level was diminished as renal function deteriorated.

CONCLUSIONS

Uric acid level was an independent predictor of mortality in patients hospitalized for AHF, but the prognostic impact of hyperuricemia was attenuated by worsening renal function.

The effect of position of (S)-2-octyloxy tail on the formation of frustrated blue phase and antiferroelectric phase in Schiff base liquid crystals

Two series of chiral salicylaldimine-based liquid crystals which differ from each other in the position of the (S)-2-octyloxy tail have been synthesized and characterized by polarizing optical microscopy, differential scanning calorimetry, and electrical switching. Compounds OH I (n = 6-7) having (S)-2-octyloxy tail close to the salicylaldimine core and compounds OH II (n = 6-11) having (S)-2-octyloxy tail far from the salicylaldimine core exhibit polymorphism of mesophases including frustrated blue phase and antiferroelectric (SmC*(A)) phases. Notably, as compared with structurally similar Schiff base compounds H I (n = 7), intramolecular hydrogen bonding in antiferroelectric salicylaldimine-based compounds OH I (n = 7) induces the frustrated blue phase. However, as compared with structurally similar Schiff base compounds OH II (n = 8), the lack of intramolecular hydrogen bonding in Schiff base compounds H II (n = 8) suppresses antiferroelectric properties.

Handwashing behaviour among Chinese adults: a cross-sectional study in five provinces

OBJECTIVES

To describe the patterns of handwashing behaviour among Chinese adults, and assess their associations with sociodemographic factors and knowledge of hand hygiene.

STUDY DESIGN

A representative sample (n = 6159) of Chinese adults aged 18-60 years in five provinces was attained by multiple-stage, stratified sampling mainly based on geographical location and economic status. Data on handwashing behaviour, knowledge of hand hygiene and sociodemographic factors were collected through self-administrated questionnaires.

METHODS

Associations between handwashing behaviour and sociodemographic factors were tested in logistic models. Path analysis was applied to examine the associations between sociodemographic factors, knowledge of hand hygiene and proper handwashing behaviour in order to evaluate the relative magnitude of these determinants and internal relationships.

RESULTS

This study found that 52.7% (rural vs urban: 44.6% vs 56.8%) and 67.3% (rural vs urban: 59.7% vs 71.1%) of Chinese adults reported they always washed hands before eating and after defaecation, and 30.0% (rural vs urban: 25.1% vs 32.8%) of adults always used soap or other sanitizers during washing. Using the criteria of 'always or very often washing hands with soap before eating and after defaecation without sharing a towel with family members after washing', only 47.2% (rural vs urban: 23.8% vs 59.1%) of the adults were graded to practice proper handwashing behaviour. Urban area, high level of education level, high level of knowledge about diseases, female gender and older age were protective factors for good hand hygiene; of these, area was found to be associated most strongly with handwashing behaviour.

CONCLUSIONS

Adherence to an appropriate handwashing method and duration of handwashing are critical problems among Chinese adults. Area difference, level of education and level of knowledge of hand hygiene were most strongly associated with handwashing behaviour, and should be targeted in future health education.

Dermatophagoides pteronyssinus 2 regulates nerve growth factor release to induce airway inflammation via a reactive oxygen species-dependent pathway

Group 2 allergen of Dermatophagoides pteronyssinus 2 (Der p2) induces airway inflammation without protease activity, and elevated nerve growth factor (NGF) levels are also found in this inflammation. How the allergen Der p2 regulates NGF release via reactive oxygen species (ROS) to induce inflammation remains unclear. In the present study, intratracheal administration of Der p2 to mice led to inflammatory cell infiltration, mucus gland hyperplasia, and NGF upregulation in the bronchial epithelium, as well as elevated ROS and NGF production in bronchoalveolar lavage fluids. In addition, Der p2 caused fibrocyte accumulation and mild fibrosis. p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) inhibitors inhibited Der p2-induced NGF release in LA4 lung epithelial cells and MLg lung fibroblasts. Pretreatment with an antioxidant, tiron, reduced the Der p2-induced ROS production, NGF expression and release, p38 MAPK or JNK phosphorylation, and airway inflammation. These results suggest that Der p2 allergen-induced airway inflammation and elevated NGF release were through increasing ROS production and a MAPK-dependent pathway. The use of an antioxidant, tiron, may provide a new therapeutic modality for the treatment of allergic asthma.

Enhanced Microwave Absorption Properties of Intrinsically Core/shell Structured La(0.6)Sr(0.4)MnO(3) Nanoparticles

The intrinsically core/shell structured La(0.6)Sr(0.4)MnO(3) nanoparticles with amorphous shells and ferromagnetic cores have been prepared. The magnetic, dielectric and microwave absorption properties are investigated in the frequency range from 1 to 12 GHz. An optimal reflection loss of -41.1 dB is reached at 8.2 GHz with a matching thickness of 2.2 mm, the bandwidth with a reflection loss less than -10 dB is obtained in the 5.5-11.3 GHz range for absorber thicknesses of 1.5-2.5 mm. The excellent microwave absorption properties are a consequence of the better electromagnetic matching due to the existence of the protective amorphous shells, the ferromagnetic cores, as well as the particular core/shell microstructure. As a result, the La(0.6)Sr(0.4)MnO(3) nanoparticles with amorphous shells and ferromagnetic cores may become attractive candidates for the new types of electromagnetic wave absorption materials. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11671-009-9374-y) contains supplementary material, which is available to authorized users.

The potential of Pseudozyma yeastlike epiphytes for the production of heterologous recombinant proteins

Although Basidiomycetes represent the most evolved class of fungi, they have been neglected with regard to recombinant gene expression. In this work, basidiomycetous yeasts belonging to Pseudozyma spp. were studied with respect to their amenability to heterologous protein production. Single plasmid or cotransformation experiments routinely afforded 100 to 200 independent transformants for the two tested species of Pseudozyma. Green fluorescent protein (GFP) was expressed in the correctly folded conformation, as demonstrated by fluorescence microscopy, and hen egg white lysozyme (HEWL) was expressed in its active form, as revealed by its lytic activity on Micrococcus lysodeikticus cells. Protease analysis established that Pseudozyma spp. contained equivalent or less extracellular protease activity than yeasts and far less protease activity than ascomycetous filamentous fungi in similar culture conditions. This proteolytic activity was inhibited by over 97% with a combination of PMSF and Pepstatin A. N-glycosylation patterns of native Pseudozyma flocculosa secreted proteins were comprised of one or a few short glycan chains that possess a classic eukaryotic structure typical of higher fungi and animal cells. This is the first report of a Basidiomycete that possesses multiple intrinsic characteristics necessary for use as a heterologous gene expression system.

Solitary fibrous tumors of the pleura: clinical, radiological, surgical and pathological evaluation

AIMS

To report a clinicopathological series of cases of solitary fibrous tumor of the pleura from Taiwan.

METHODS

Clinical data was collected from a review of medical records and telephone interviewing for follow-up.

RESULTS

Eight patients, three men and five women aging from 34 to 71 years, underwent tumor resection and were followed in a period from 7 months to 13.5 years. Six patients underwent standard thoracotomy and two had VATS for tumor excision. Tumors were pathologically benign in seven patients and malignant in one. Patients were all alive with no evidence of tumor recurrence at the time of this report.

CONCLUSIONS

One should always consider SFTPs as potentially malignant tumors. Complete resection remains the mainstay of cure. Standard thoracotomy should always be considered when a high suspicion of malignancy is raised, whereas VATS may be a preferred approach for smaller tumors.

Establishment of a gene transfer system for Pseudozyma flocculosa, an antagonistic fungus of powdery mildew fungi

A reliable DNA-mediated transformation system has been developed for Pseudozyma flocculosa, a fungus that is antagonistic to powdery-mildew fungi. Plasmids harboring various selectable markers under the control of different promoters were tested. Molecular analyses demonstrated that successful transformation could be achieved using a plasmid that confers resistance to hygromycin B under the control of the Ustilago maydis hsp70 promoter and terminator sequences. On average, 1-40 (mean = 20) transformants were obtained per 10 microg of linearized DNA per 10(8) protoplasts. Southern analysis of the transformants revealed that, in each case, the vector had integrated in multiple tandem copies into the genome of P. flocculosa, and that integration events were random. Pulsed-field gel electrophoresis was employed to separate the genome of P. flocculosa into at least 11 chromosomes with sizes ranging from 0.55 Mb to 2.9 Mb. Hybridization with the plasmid indicated that integration of vector DNA had occurred in one to several chromosomes depending on the transformant examined.

Diffuse leiomyomatosis of the esophagus

BACKGROUND

Leiomyomas are rare esophagus neoplasms. They are usually solitary, and the diffuse lesion is extremely rare.

CASE REPORT

A 19-year-old male presented with a 3-year history of occasional dysphagia and postprandial regurgitation. The chest radiographs showed a huge mass in the posterior mediastinum. Barium esophagograms showed narrowing of the middle third esophagus with proximal dilatation. The fibroesophagoscopy demonstrated multiple submucosal nodules below a level 22 cm from the incisor and covered with intact mucosa. CT scans of the chest showed a long segment of circumferential soft tissue in the posterior mediastinum which encircled and involved the upper two thirds of the esophagus. An intrathoracic esophagectomy with cervical esophagogastrostomy via the substernal route was performed. Grossly, multiple confluent myomatous nodules circumferentially involved the upper and middle third of the esophagus. Histologic findings showed diffuse leiomyomatosis of the esophagus.

CONCLUSION

Esophageal leiomyomatosis should be considered in a young patient with long-standing dysphagia in whom smooth, tapered esophageal narrowing on barium study and circumferential esophageal wall thickening on CT scan are seen. An esophagectomy combined with a reconstruction procedure is indicated.

Urea reduction ratio that considers effects of ultrafiltration and intradialytic urea generation

We modified the urea reduction ratio (URR) equation to correct the effects of ultrafiltration and intradialytic urea generation on the delivered dose of hemodialysis: mURR = [1 - (R/1 + 2*UF/BW) + 0.01*t] x 100% where mURR is modified URR, R is postdialysis plasma urea nitrogen (PUN) to predialysis PUN ratio, UF is ultrafiltrate volume in liters, BW is postdialysis body weight in kilograms, and t is dialysis session length in hours. The equation was validated against 145 hemodialysis treatments on 33 stable maintenance dialysis patients. The mURR values obtained closely predicted single-pool Kt/V (spKt/V) values. In contrast to conventional URR, the range of spKt/V values at each mURR value is narrow over a wide range of UF, t, and R values. Based on the mURR equation, mURR values of 64%, 70%, and 76% are mathematically equivalent to spKt/V levels of 1.0, 1.2, and 1.4, respectively. This equation can be a useful bedside tool to quantify hemodialysis dose.

Stability of urea and creatinine in spent hemodialysate

Urea and creatinine levels in spent hemodialysates showed only small declines in spite of incubation at 37 degrees C for 36 hours. In the determination of dialysate-side solute removal, it would seem prudent to keep spent dialysate cold during collection to retard bacterial breakdown of these waste products.

Hemangiopericytoma of the pleura causing massive hemothorax

Hemangiopericytoma is an unusual soft tissue tumor. A 54-year-old man presented with sudden onset of chest pain and dyspnea for 1 day. The initial chest x-ray showed a massive left pleural effusion. A contrast-enhanced computed tomographic scan of the chest showed a homogenously enhanced mass in the intrathoracic extrapulmonary space. A tube thoracostomy was performed and hemothorax was confirmed. A posterolateral thoracotomy was performed and a tumor in the parietal pleura of the left chest wall was resected. Grossly, the resected tumor arose from the parietal pleura, and the cut surface was elastic, soft, and pale yellow. There were several cystic formations and hemorrhages. Based on histologic findings, hemangiopericytoma with lower grade malignancy was diagnosed. The patient was alive and free from tumor recurrence 1 year after surgery. Intrathoracic extrapulmonary hemangiopericytoma is extremely rare, and surgical excision is the treatment of choice. Adjuvant chemotherapy or radiotherapy is indicated because of the high risk of recurrence and potential malignancy.

Haemopneumothorax from congenital cystic adenomatoid malformation in a cryptorchidism patient

Congenital cystic adenomatoid malformation (CCAM) of the lung is an uncommon congenital anomaly, especially in young adults. This study reports an 18-yr-old male with CCAM involving the right upper lobe, who presented with a moderate spontaneous haemopneumothorax initially. The patient also had bilateral abdominal cryptorchidism which required surgical treatment earlier in childhood. The chest radiographs and contrast-enhanced computed tomographic scan of the chest showed a multicystic lesion with air-fluid levels in the right upper lung. The right upper lobe was resected through a posterolateral thoracotomy. Histological examination confirmed the diagnosis of CCAM. To the authors' knowledge, congenital cystic adenomatoid malformation presenting with spontaneous haemopneumothorax and haemoptysis has never been described in the literature.

The pilH gene encodes an ABC transporter homologue required for type IV pilus biogenesis and social gliding motility in Myxococcus xanthus

Type IV pilus genes have been shown to be required for social gliding motility in Myxococcus xanthus. We report the discovery of four additional pil genes: pilD, a homologue of type IV prepilin leader peptidases; and pilG, pilH and pilI, which have no known homologues in other type IV pilus systems. pilH encodes an ATP-binding cassette (ABC) transporter homologue, the first such homologue to be required for the biogenesis of any bacterial pilus type. pilG and pilI are co-transcribed with pilH and appear to be functionally related to pilH. Null mutants of pilG, pilH and pilI all lack social motility, are deficient in pilus production, have elevated sporulation efficiencies and display similar developmental abnormalities. In addition, all three mutations reduced the amount of PilA found in the supernatant after cells were sedimented from liquid culture. We suggest that the products of these three genes form a single ABC exporter complex, in which pilI is an integral membrane protein with membrane-spanning domains, and pilG is an accessory factor. The complex may participate in pilus assembly and/or the export of PilA pilin.

Determination of the solute removal index for urea by using a partial spent dialysate collection method

In 22 hemodialysis patients, during a dialysis session, the solute removal index (SRI) for urea obtained from the use of a partial spent dialysate collection method was compared with that derived from the use of a total spent dialysate collection technique. The partial spent dialysate collection method was used to harvest a small representative sample of the total spent dialysate. The volumes of spent dialysate collected by the partial and the total spent dialysate collection methods were 1.7 +/- 0.4 L and 129.6 +/- 15.3 L, respectively. The total amount of urea nitrogen removed by dialysis as estimated by the partial spent dialysate collection method was similar to that determined by the total spent dialysate collection approach. As a result, the SRI value for urea obtained by the partial spent dialysate collection method (namely, 63% +/- 8%) correlated very well (r = 0.95, P < 0.001) with that derived by the total spent dialysate collection technique (namely, 62% +/- 8%). Our data suggest that it is feasible to use a simple partial spent dialysate collection method to obtain SRI results in patients treated with hemodialysis.

Acid-base values of single pass, batch system, bicarbonate based hemodialysate

The bicarbonate, calcium, and magnesium values of a single pass, batch system, bicarbonate based hemodialysate were found to be stable during a period of 5 hours, whether the solution was extensively covered by a floating polystyrene lid or not. The pH and PCO2 of the dialysate that had been covered with a floating lid remained stable during the 5 hours, whereas the corresponding values of the dialysate that had not been so covered did show changes that were secondary to the loss of carbon dioxide. The changes were not marked enough to preclude the clinical use of the latter uncovered dialysate.

Drug distribution in the vitreous humor of the human eye: the effects of aphakia and changes in retinal permeability and vitreous diffusivity

The majority of eyes that receive drug therapy exhibit some form of pathophysiological degradation. Two common pathophysiological states are retinal inflammation, which results in breakdown of the blood-retinal barrier, and aphakia. The purpose of this study was to examine the effects of aphakia and changes in retinal permeability and vitreous diffusivity on drug distribution in the vitreous humor of the human eye. The study was performed using a finite element model that accurately accounts for the vitreous geometry and boundary conditions. Intravitreal injection is the most common method for treating posterior segment disorders; therefore, this administration method was simulated using the models. Elimination from aphakic and phakic eyes was compared for four extreme injection locations and for two retinal permeabilities. When the retinal permeability was fixed at 5.0 x 10(-5) cm/s, increasing the drug diffusivity through the vitreous from 5.4 to 10(-7) to 2.4 x 10(-5) cm2/s decreased the half-life of drug from 64 hours to 2.7 hours. When the drug diffusivity was fixed at 5.6 x 10(-6) cm2/s, increasing the retinal permeability of the drug from 1.0 x 10(-7) to 1.0 x 10(-4) cm/s decreased the half-life of drug from 44 to 7 hours. Therefore, drug diffusivity and retinal permeability are key factors that influence elimination from the vitreous, and must be considered, particularly if the blood retinal barrier has been compromised. Faster drug elimination was observed in aphakic eyes than in phakic eyes, especially for drugs with a low retinal permeability and injected close to the lens capsule. Injection position is also important if the drug is injected in close proximity to a primary elimination barrier.

Drug distribution in the vitreous humor of the human eye: the effects of intravitreal injection position and volume

PURPOSE

The purpose of this study was to determine how the position and volume of an intravitreal injection affect the distribution and elimination of drug from the vitreous humor.

METHODS

A mathematical model that had been developed and used previously to study drug distribution in the vitreous humor of the rabbit eye was modified to match the physiology of the human eye. Fluorescein and fluorescein glucuronide were used as the model compounds for these studies. Four extreme injection locations were considered: a central injection, an injection displaced towards the retina, an injection displaced towards the lens, and an injection displaced toward the hyaloid membrane. Injections containing an equal mass of drug dissolved in volumes of either 15 microL or 100 microL were compared.

RESULTS

The location of an intravitreal injection was found to have a substantial effect on elimination and distribution in the vitreous. Peak concentrations at different vitreous locations varied by over three orders of magnitude, depending on the injection location. The mean concentration of drug remaining in the vitreous 24 hours after the intravitreal injection varied by up to a factor of 3.8, depending on the injection location. Changing the volume of the injection from 15 microL to 100 microL dampened the effects of the initial injection location; however, meant concentrations at 24 hours still varied by up to a factor of 2.5.

CONCLUSIONS

Careful control of the conditions of an intravitreal injection could reduce treatment variability, improve bioavailability, and reduce the possibility of retinal toxicity.

A semi-solid drug delivery system for epidermal growth factor in corneal epithelial wound healing

PURPOSE

To examine the effects of EGF, delivered from a semi-solid drug delivery system, on corneal epithelial wound healing following anterior keratectomy wound creation in the eyes of New Zealand white rabbits.

METHODS

A semi-solid drug delivery system based on a Carbopol gel was developed. Following creation of a 7.5 mm circular anterior keratectomy wound, 50 microL of either a placebo gel or an EGF-containing gel, was instilled in the inferior fornix. The gel remained in the eye for 8 hours, at which time it was removed. Anaesthesia was maintained for the entire 8-hour period. Wound healing was evaluated by quantitative morphometry. We evaluated 0.04, 0.1, 0.2, 0.4, and 1% EGF concentrations in the gel. Tear EGF concentrations and histology of the healing corneas were also examined.

RESULTS

The enhancement factor (ratio of the healing rate with the EGF gel and control gel) was 1.13 +/- 0.12, 1.40 +/- 0.14, 1.29 +/- 0.12, 1.80 +/- 0.22, and 1.09 +/- 0.12 for the gels containing 0.04, 0.1, 0.2, 0.4, and 1% EGF by mass, respectively. The increases in the rate of wound healing were significant with the 0.1, 0.2 and 0.4% gel formulations. Histologically, the 0.4% gels resulted in cellular hyperplasia after 5 days of healing. Differences between the placebo gel-treated and EGF-containing gel-treated eyes were evaluated at both 2 and 5 days. The concentration of EGF in the tears during the treatment period was approximately constant for both the 1% and 0.04% gels. The average tear concentration during the instillation period was 2.87 +/- 0.36 micrograms/mL and 200.61 ng/mL +/- 116.10 for the 1% and 0.04% gels respectively.

CONCLUSIONS

Treatment with EGF in a Carbopol gel carrier for a period of 8 hours results in significant wound healing enhancement (p < 0.05). The optimum EGF loading in the gel was determined to be 0.4%. A slow release gel may be an effective way to deliver EGF to the corneal surface.

Finite element modeling of drug distribution in the vitreous humor of the rabbit eye

Direct intravitreal injection of drug is a common method for treating diseases of the retina or vitreous. The stagnant nature of the vitreous humor and surrounding tissue barriers creates concentration gradients within the vitreous that must be accounted for when developing drug therapy. The objective of this research was to study drug distribution in the vitreous humor of the rabbit eye after an intravitreal injection, using a finite element model. Fluorescein and fluorescein glucuronide were selected as model compounds due to available experimental data. All required model parameters were known except for the permeability of these compounds through the retina, which was determined by fitting model predictions to experimental data. The location of the intravitreal injection in the experimental studies was not precisely known; therefore, several injection locations were considered, and best-fit retinal permeability was determined for each case. Retinal permeability of fluorescein and fluorescein glucuronide estimated by the model ranged from 1.94 x 10(-5) to 3.5 x 10(-5) cm s(-1) and from 0 to 7.62 x 10(-7) cm s(-1), respectively, depending on the assumed site of the injection. These permeability values were compared with values previously calculated from other models, and the limitations of the models are discussed. Intravitreal injection position was found to be an important variable that must be controlled in both experimental and clinical settings.

A partial dialysate collection method

This study validates Ing's partial dialysate collection method, which employs proportionate collection using a side tube capped with a small-gauge plastic needle. The urea nitrogen and creatinine levels of the small representative fraction of spent dialysate collected in the above fashion are undistinguishable from those obtained from the total spent dialysate. The estimated urea nitrogen removed during hemodialysis using this approach is similar to that using the total dialysate collection method; Ing's method is simple and useful in quantifying the dialysis dosage and in its assessment of the nutritional status of patients on hemodialysis.