Coping, connection appraisal, and well-being during COVID-19 in the U.S., Japan, and Mexico.

Introduction: The COVID-19 pandemic has affected nearly every facet of life, constituting a "new normal" and prompting an ongoing collective psychological crisis. People's ways of coping with the pandemic and corresponding well-being are of particular research interest; however, these constructs have largely been examined using deductive quantitative approaches, deficit-based lenses, and mononational samples. Methods: The current mixed-methods study used inductive-sequential (QUAL → QUAN) approaches to explore positive coping strategies (approach coping style and COVID-related connection appraisal) and well-being (loneliness, distress, and happiness) across individuals from the United States, Japan, and Mexico. Qualitative data were gathered from N = 141 U.S., Japanese, and Mexican adults to examine how people perceived connection during the pandemic. Results: Qualitative analyses illuminated common themes in which people appraised the pandemic as an opportunity for connection and strengthened interpersonal relationships. Quantitative measures, including a newly-developed questionnaire on COVID-related connection appraisal, were then administered to a separate sample of N = 302 adults in the U.S, Japan, and Mexico to assess associations among approach coping style, COVID-related connection appraisal, and well-being outcomes (loneliness, distress, happiness). Quantitative analyses found significant associations among approach coping style, COVID-related connection appraisal, and all well-being outcomes. Of note, these associations did not differ by country. COVID-related connection appraisal mediated the relationship between approach coping style and two well-being outcomes (loneliness and happiness). Discussion: Findings point to approach coping style and connection appraisal as pathways for resilience and growth in the face of global suffering.

Bioinspired Antimicrobial PLA with Nanocones on the Surface for Rapid Deactivation of Omicron SARS-CoV-2.

Bioinspired bactericidal surfaces are artificial surfaces that mimic the nanotopography of insect wings and are capable of inhibiting microbial growth by a physicomechanical mechanism. The scientific community has considered them an alternative method to design polymers with surfaces that inhibit bacterial biofilm formation, suitable for self-disinfectant medical devices. In this contribution, poly(lactic acid) (PLA) with nanocone patterns was successfully produced by a novel two-step procedure involving copper plasma deposition followed by argon plasma etching. According to reverse transcription-quantitative polymerase chain reaction tests, the bioinspired PLA nanostructures display antiviral performance to inactivate infectious Omicron severe acute respiratory syndrome coronavirus 2 particles, reducing the amount of the viral genome to less than 4% in just 15 min due to a possible combined effect of mechanical and oxidative stress. The bioinspired antiviral PLA can be suitable for designing personal protection equipment to prevent the transmission of contagious viral diseases, such as Coronavirus Disease 2019.

TRANSLATION AND VALIDATION OF ENGLISH VERSION OF EVIDENCE-BASED PRACTICE COMPETENCE QUESTIONNAIRE.

Background: Valid and reliable tools must be implemented to measure nursing students' evidence-based practice (EBP) knowledge and skills that transfer to their practice. Purpose: To-translate and validate the English version of the Evidence Based Practice Competence Questionnaire (EBP-COQ-E). Methods: The EBP-COQ developed by Ruzafa-Martinez in Spain was administered to a sample of 279 undergraduate nursing students. Results: The content validity index was 96.16%, indicating that all items were correlated with the measurement of EBP competence. The Cronbach's alpha was 0.83, indicating good internal consistency. In confirmatory factor analysis, a three-factor solution was extracted with an eigenvalue greater than one, indicating a good measure of what it purports to be measuring. Conclusion: EBP-COQ-E can be recommended for standard implementation in English-speaking students taking EBP courses.

Delta SARS-CoV-2 inactivation and bactericidal performance of cotton wipes decorated with TiO2/Ag nanoparticles like Brazilian heavy-fruited Myrciaria cauliflora.

The current pandemic of Coronavirus Disease 2019 (COVID-19) raised several concerns about using conventional textiles for manufacturing personal protective equipment without self-disinfecting properties since the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is transmitted mainly by aerosols that can transpose cotton masks. Therefore, developing new cotton fibers with high self-disinfecting ability is essential to avoid a new pandemic due to new SARS-CoV-2 variants. Herein, we developed cotton wipes (CFs) with fibers coated by Ag, TiO2, and Ag/TiO2 hybrid nanoparticles like Brazilian heavy-fruited Myrciaria cauliflora by a sonochemical approach. Moreover, the coated CFs present high antimicrobial performance against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), being able to inactivate infectious SARS-CoV-2 (Delta variant) by the destruction of the spike, membrane, and nucleocapsid proteins while the viral RNA is not significantly affected, according to the molecular biological findings.

Silver nanoparticles intensify the allelopathic intensity of four invasive plant species in the Asteraceae.

This study aimed to estimate the allelopathic intensity of four Asteraceae invasive plant species (IPS), including Conyza canadensis (L.) Cronq., Erigeron annuus (L.) Pers., Bidens pilosa (L.), and Aster subulatus Michx., by testing the effect of leaf extracts on the seed germination and seedling growth (SGe and SGr) of lettuce (Lactuca sativa L.) in combination with two particle sizes of silver nanoparticles. These four IPS decreased the germination of lettuce seeds but increased the growth of lettuce seedlings. The allelopathic intensity of the four IPS decreased in the following order: B. pilosa > C. canadensis > E. annuus > A. subulatus. Silver nanoparticles decreased the SGe and SGr of lettuce. The 20 nm silver nanoparticles affected the competition intensity for water and the absorption of inorganic salts by lettuce more intensively than the 80 nm nanoparticles. Silver nanoparticles intensify the allelopathic intensity of the four invasive plant species on the SGe and SGr of lettuce. The allelopathic intensity of B. pilosa was higher than that of the other three IPS when they were polluted with silver nanoparticles. Thus, silver nanoparticles could facilitate the invasion process of the four IPS, particularly B. pilosa, via an increase in the intensity of allelopathy.

Association of Metformin Use During Hospitalization and Mortality in Critically Ill Adults With Type 2 Diabetes Mellitus and Sepsis.

OBJECTIVES: Whether metformin exposure is associated with improved outcomes in patients with type 2 diabetes mellitus and sepsis. DESIGN: Retrospective cohort study. SETTING: Patients admitted to ICUs in 16 hospitals in Pennsylvania from October 2008 to December 2014. PATIENTS: Adult critical ill patients with type 2 diabetes mellitus and sepsis. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We conducted a retrospective cohort study to compare 90-day mortality in diabetic patients with sepsis with and without exposure to metformin during hospitalization. Data were obtained from the electronic health record of a large healthcare system in Pennsylvania from October 2008 to December 2014, on patients admitted to the ICU at any of the 16 hospitals within the system. The primary outcome was mortality at 90 days. The absolute and adjusted odds ratio (OR) with 95% CI were calculated in a propensity score-matched cohort. Among 14,847 patients with type 2 diabetes mellitus and sepsis, 682 patients (4.6%) were exposed to metformin during hospitalization and 14,165 (95.4%) were not. Within a total of 2,691 patients subjected to propensity score-matching at a 1:4 ratio, exposure to metformin (n = 599) was associated with decreased 90-day mortality (71/599, 11.9% vs 475/2,092, 22.7%; OR, 0.46; 95% CI, 0.35-0.60), reduced severe acute kidney injury (50% vs 57%; OR, 0.75; 95% CI, 0.62-0.90), less Major Adverse Kidney Events at 1 year (OR, 0.27; 95% CI, 0.22-0.68), and increased renal recovery (95% vs 86%; OR, 6.43; 95% CI, 3.42-12.1). CONCLUSIONS: Metformin exposure during hospitalization is associated with a decrease in 90-day mortality in patients with type 2 diabetes mellitus and sepsis.

Longitudinal changes in oxidative stress and early renal injury in children exposed to DEHP and melamine in the 2011 Taiwan food scandal.

In 2011, phthalates, mainly di-(2-ethylhexyl) phthalate (DEHP), were found to have been added to a variety of foods in Taiwan, increasing the risk of microalbuminuria in children. Exposure to melamine perhaps modifies that risk. This prospective cohort study investigates whether renal injury resulting from exposure to DEHP-tainted foods from the 2011 Taiwan Food Scandal is reversed over time. The temporal and interactive effects of past daily DEHP intake, current daily DEHP intake, and urinary melamine levels on oxidative stress and renal injury were also examined. Two hundred possibly DEHP-affected children (aged < 18 years) were enrolled in the first survey wave (August 2012-January 2013), with 170 and 159 children in the second (July 2014-February 2015) and third waves (May 2016-October 2016), respectively. The first wave comprised questionnaires that were used to collect information about possible past daily DEHP intake from DEHP-tainted foods. One-spot first morning urine samples were collected to measure melamine levels, phthalate metabolites, and markers indicating oxidative stress (malondialdehyde and 8-oxo-2'-deoxyguanosine), and renal injury (albumin/creatinine ratio (ACR) and N-acetyl-beta-D-glucosaminidase) in all three waves. Generalized estimating equation (GEE) modeling revealed that both past daily DEHP intake and time might affect urinary ACR. However, most interactions were negative and significant correlation was observed only during the second wave (P for interaction = 0.014) in the group with the highest past daily DEHP intake (>50 µg/kg/day). Urinary melamine levels were found to correlate significantly with both urinary ACR and oxidative stress markers. The highest impact associated with exposure to DEHP-tainted foods in increasing urinary ACR of children was observed during the first wave, and the effect may partially diminish over time. These results suggest that continuous monitoring of renal health and other long-term health consequences is required in individuals who were affected by the scandal in 2011.

Implicit support differs across five groups in the U.S., Taiwan, and Mexico.

Objective: Prior research documents numerous psychological and physiological benefits of implicit support particularly for Asians/Asian Americans. However, potential variation in how two different kinds of collectivism-Harmony and Convivial-shape support has been overlooked. Additionally, implicit support has largely been studied using quantitative approaches, whereas qualitative methods may best illuminate how implicit support is used in everyday life. The present mixed-methods investigation aims to better understand implicit support "in practice" and to unpack previously overlooked nuances between different subsets of collectivism in implicit support processes. Method: We collected qualitative accounts of implicit support interactions from 216 female participants (U.S. Whites, U.S. Latinas, U.S. Asians, Mexican, Taiwanese) who were prompted to describe an implicit support experience and then quantitatively assess its helpfulness. Results: Qualitative analysis using a thematic analysis approach identified three subcategories of implicit support (traditional, semi-disclosure, non-verbal cues). Cultural patterns emerged in how implicit support was used across different groups that align with high-context and low-context communication theories and cultural values. Conclusions: The current research highlights the benefit of qualitative approaches to understanding nuanced support processes, and the need to study culture beyond the individualism-collectivism dichotomy. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Biodegradable Nanocomposite Microcapsules for Controlled Release of Urea.

Urea is the most used fertilizer around the world as the main source of nitrogen to soil and plants. However, the administration of nitrogen dosage is critical, as its excess can be harmful to the environment. Therefore, the encapsulation of urea to achieve control on its release rates has been considered in several areas. In this work, encapsulation of urea by biodegradable polymer poly(3-hydroxybutyrate) (PHB) and its nanocomposites, namely PHB/MMT and PHB/OMMT, producing microcapsules by emulsion method is carried out. MMT and OMMT refer to Brazilian clays in a natural state and organophilized, respectively. In addition, the microcapsules are thus prepared to have their physicochemical characteristics investigated, then tested for biodegradation. Increment of microcapsules' crystallinity due to the increased amount of poly(vinylacetate) (PVA), as emulsifier agent in the continuous phase, was confirmed by X-ray diffractometry (XRD) and atomic force microscopy (AFM). The presence of urea within microcapsules was verified by XRD, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The soil biodegradation assessments showed that PHB/OMMT microcapsules present higher degradation rates in sandy soils. The overall results suggest that the composites performed better than neat PHB and are very promising; moreover, PHB/OMMT microcapsules proved to be the best candidate for the controlled-release of urea in soils.

Accuracy of the tuberculosis point-of-care Alere determine lipoarabinomannan antigen diagnostic test using α-mannosidase treated and untreated urine in a cohort of people living with HIV in Guatemala.

BACKGROUND: Improved point-of-care diagnostic tests for tuberculosis (TB) in severe immune suppressed people living with HIV (PLWH) are needed to decrease morbidity and mortality outcomes. The aim of the study is to evaluate the performance of the lipoarabinomannan antigen test (LAM-test) with and without α-mannosidase pre-treated urine in a cohort of PLWH in primary care clinics in Guatemala. We further determined TB incidence, and mortality rates and its risk factors in PLWH with TB symptoms. METHODS: Prospective longitudinal study of PLWH with TB symptoms. Urine samples were collected at 2 HIV sites to test the sensitivity of the LAM-test in urine with and without α-mannosidase pre-treatment. A composite reference standard of either a positive Mycobacterium tuberculosis complex culture and/or GeneXpert® MTB/RIF (Xpert, Cepheid, Sunnyvale, CA, USA) results was used in the LAM-test diagnostic accuracy studies. Cox proportional hazards regression was used to study mortality predictors. RESULTS: The overall sensitivity of the LAM-test was of 56.1% with 95% CI of (43.3-68.3). There were no differences in the LAM-test sensitivity neither by hospital nor by CD4 T cell values. LAM-test sensitivity in PLWH with < 200 CD4 T cells/µl was of 62.2% (95% CI 46.5-76.2). There were no significant differences in sensitivity when comparing LAM-test results obtained from untreated vs. α-mannosidase treated urine [55.2% (95% CI 42.6-67.4) vs. 56.9% (95% CI 44-69.2), respectively]. TB incidence in our cohort was of 21.4/100 person years (PYs) (95% CI 16.6-27.6), and mortality rate was of 11.1/100 PYs (95% CI 8.2-15.0). Importantly, PLWH with a positive LAM-test result had an adjusted hazard ratio (aHR) of death of 1.98 (1.0-3.8) with a significant p value of 0.044 when compared to PLWH with a negative LAM-test result. CONCLUSIONS: In this study, α-mannosidase treatment of urine did not significantly increase the LAM-test performance, however; this needs to be further evaluated in a large-scale study due to our study limitations. Importantly, high rates of TB incidence and mortality were found, and a positive LAM-test result predicted mortality in PLWH with TB clinical symptoms.

Upper urinary tract stone compositions: the role of age and gender

ABSTRACT Objective: To analyze the compositions of upper urinary tract stones and investigate their distributions in different gender and age groups. Materials and Methods: Patients diagnosed with upper urinary tract stone disease between December 2014 and March 2018 were retrospectively reviewed. Patient's age, gender, BMI, comorbidities, stone event characteristics, and compositions were collected, and proportions of stone components in different gender and age groups were analyzed. Results: A total of 1532 stone analyses were performed (992 from males and 540 from females). The mean age was younger in males (p <0.001). Males included more cases with larger BMI, hyperuricemia, and obesity, while females had more urinary tract infections. Multiple components were present in 61.8% of stones. Calcium oxalate (CaOx) (67.0%) was the most common component, followed by uric acid (UA) (11.8%), infection stone (11.4%), calcium phosphate (CaP) (8.0%), cystine (1.1%), brushite (0.4%), and 2, 8-dihydroxyadenine (0.2%). Men contributed with more CaOx stones than women at age 30-49 years (all p <0.01) and more UA stones at 30-59 years (all p <0.05). Women contributed with more infection stones than men in age groups 30-49 and 60-69 years (all p <0.05), and more CaP stones at 30-49 years. The prevalence peak was 50-59 years in men and 60-69 years in women. Both genders had the lowest prevalence in adolescence. Prevalence of UA stones increased while that of infection stones decreased with aging in both genders. Conclusions: Age and sex had a strong association with distribution of stone compositions in this Chinese cohort.

Relationship of gender and age on thyroid hormone parameters in a large Chinese population

ABSTRACT Objective This study aimed to present the impact of age and gender on thyroid hormone levels in a large Chinese population with sufficient iodine intake. Subjects and methods A total of 83643 individuals were included and were stratified by age and gender. The median, 2.5th and 97.5th of thyrotropin (TSH), free triiodothyronine (FT3), free thyroxine (FT4) and FT3/FT4 ratio were calculated for both genders for every decade from 18 to over 80 years. TSH, FT3, FT4, FT3/FT4 distribution in each age group was evaluated for females and males using smoothing splines in the generalized additive models (GAM). TSH concentrations were compared in the different age groups in gender. Results In the over 80s age group, the TSH level (median: 2.57 mIU/L, 2.5th-97.5th: 0.86-7.56 mIU/L) was significantly higher than other age groups, irrespective to gender (P<0.001). Females had a higher TSH value than males in all age groups (P<0.001). Results of the smoothing curves showed that TSH increased with age, FT3 concentration was higher in males than in females and the tendency of the FT3/FT4 ratio was basically similar to that of FT3. TSH concentration in the 50s age group (median 2.48 mIU/L for females versus 2.00 mIU/L for males) was significantly higher than that in the 30s age group (median 2.18 mIU/L for females versus median 1.85 mIU/L for males). Conclusions In accord with increasing TSH values during aging, females and older adults have lower FT3 values and lower FT3/FT4 ratios, while the FT4 values remain stable.

Upper urinary tract stone compositions: the role of age and gender.

OBJECTIVE: To analyze the compositions of upper urinary tract stones and investigate their distributions in different gender and age groups. MATERIALS AND METHODS: Patients diagnosed with upper urinary tract stone disease between December 2014 and March 2018 were retrospectively reviewed. Patient's age, gender, BMI, comorbidities, stone event characteristics, and compositions were collected, and proportions of stone components in different gender and age groups were analyzed. RESULTS: A total of 1532 stone analyses were performed (992 from males and 540 from females). The mean age was younger in males (p<0.001). Males included more cases with larger BMI, hyperuricemia, and obesity, while females had more urinary tract infections. Multiple components were present in 61.8% of stones. Calcium oxalate (CaOx) (67.0%) was the most common component, followed by uric acid (UA) (11.8%), infection stone (11.4%), calcium phosphate (CaP) (8.0%), cystine (1.1%), brushite (0.4%), and 2,8-dihydroxyadenine (0.2%). Men contributed with more CaOx stones than women at age 30-49 years (all p<0.01) and more UA stones at 30-59 years (all p<0.05). Women contributed with more infection stones than men in age groups 30-49 and 60-69 years (all p<0.05), and more CaP stones at 30-49 years. The prevalence peak was 50-59 years in men and 60-69 years in women. Both genders had the lowest prevalence in adolescence. Prevalence of UA stones increased while that of infection stones decreased with aging in both genders. CONCLUSIONS: Age and sex had a strong association with distribution of stone compositions in this Chinese cohort.

Relationship of gender and age on thyroid hormone parameters in a large Chinese population.

Objective This study aimed to present the impact of age and gender on thyroid hormone levels in a large Chinese population with sufficient iodine intake. Subjects and methods A total of 83643 individuals were included and were stratified by age and gender. The median, 2.5th and 97.5th of thyrotropin (TSH), free triiodothyronine (FT3), free thyroxine (FT4) and FT3/FT4 ratio were calculated for both genders for every decade from 18 to over 80 years. TSH, FT3, FT4, FT3/FT4 distribution in each age group was evaluated for females and males using smoothing splines in the generalized additive models (GAM). TSH concentrations were compared in the different age groups in gender. Results In the over 80s age group, the TSH level (median: 2.57 mIU/L, 2.5th-97.5th: 0.86-7.56 mIU/L) was significantly higher than other age groups, irrespective to gender (P<0.001). Females had a higher TSH value than males in all age groups (P<0.001). Results of the smoothing curves showed that TSH increased with age, FT3 concentration was higher in males than in females and the tendency of the FT3/FT4 ratio was basically similar to that of FT3. TSH concentration in the 50s age group (median 2.48 mIU/L for females versus 2.00 mIU/L for males) was significantly higher than that in the 30s age group (median 2.18 mIU/L for females versus median 1.85 mIU/L for males). Conclusions In accord with increasing TSH values during aging, females and older adults have lower FT3 values and lower FT3/FT4 ratios, while the FT4 values remain stable.

Acute Kidney Injury in Critically Ill Patients After Noncardiac Major Surgery: Early Versus Late Onset.

OBJECTIVES: Acute kidney injury is a common complication of major surgery. However, acute kidney injury occurring within the first 48 hours after surgery (early acute kidney injury) and therefore likely related to the surgery itself is possibly different from acute kidney injury occurring after 48 hours (late acute kidney injury). The aim of this study was to describe the epidemiology and identify differences in risk factors and outcomes between early and late acute kidney injury following major surgery. DESIGN: Retrospective cohort study. SETTING: Academic Medical Center. PATIENTS: Patients admitted to ICU following noncardiac major surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We analyzed data from 3,499 patients and defined acute kidney injury according to full Kidney Disease: Improving Global Outcomes criteria and classified as early (48 hr or less) or late (> 48 hr to 7 d) based on time from surgery. Separate multivariable logistic regression models were fit to identify risk factors of early acute kidney injury compared with no acute kidney injury and risk factors of late acute kidney injury compared with no acute kidney injury. Overall 41.7% (1,459/3,499) developed early acute kidney injury versus 14.4% (504/3,499) late acute kidney injury. Most acute kidney injury occurred within 48 hours following surgery and 12 hours was the peak interval. Risk factors for early acute kidney injury included increased age, body mass index, decreased estimated glomerular filtration rate, and anemia, whereas late acute kidney injury cases were closely associated with postoperative factors, like sepsis, mechanical ventilation, positive fluid balance, blood transfusions and exposure to diuretics, vasopressors, and nonsteroidal anti-inflammatory drugs. After adjusting for age, body mass index, estimated glomerular filtration rate, comorbidities, surgery type, both early acute kidney injury (odds ratio [95% CI], 1.84 [1.50-2.27]) and late acute kidney injury (odds ratio [95% CI], 1.42 [1.09-1.85]) were associated with higher 1-year mortality compared with patients without acute kidney injury. We found similar results in a validation cohort of 10,723 patients admitted between 2008 and 2014. CONCLUSIONS: Most surgery-related acute kidney injury occurred within 48 hours of surgery. Acute kidney injury occurring within the first 48 hours was associated with underlying health, whereas acute kidney injury occurring after 48 hours was related to postoperative complications or drugs. Design of clinical and experimental interventions for acute kidney injury in this population should consider these differences.

The UALE project: a cross-sectional approach for trends in HIV/STI prevalence among key populations attending STI clinics in Guatemala.

OBJECTIVE: To describe and compare trends in prevalence, sexual behaviour and HIV transmission knowledge data related to sexually transmitted infections (STI) and HIV in patients attending three STI clinics over an 8-year period in Escuintla Department, Guatemala. METHODS: STI clinic attendees were classified into transmission groups as follows: female sex workers (FSW), men who have sex with men (MSM) and 'high-risk heterosexuals' (HRH). Annual cross-sectional analysis and multivariable Poisson regression adjusted for sociodemographic variables were used for prevalence comparisons and adjusted prevalence trends for HIV/STI outcomes and used for adjusted trends in proportions in sexual behaviour and HIV transmission knowledge outcomes. Endocervical swabs were obtained to detect trichomonas, chlamydia and neisseria infections. Serologies for syphilis and HIV were performed using rapid tests. For reactive HIV samples, positivity was confirmed by an ELISA. All reactive syphilis samples were further confirmed for diagnosis of active syphilis disease. RESULTS: From a total of 4027 clinic attendees, 3213 (79.78%) were FSW, 229 (5.69%) were MSM and 585 (14.53%) were HRH. The proportion of FSW, MSM and HRH who had a single visit was 56.42%, 57.23% and 91.10%, respectively. Overall, HIV prevalence was 2.10% in FSW, 8.17% in MSM and 4.12% in HRH. Prevalence trends in HIV and syphilis decreased in FSW. Prevalence trends in gonorrhoea did not decrease over time neither in FSW nor in HRH. Chlamydia and trichomonas infections in HRH showed an increase prevalence trend. In FSW, trends in condom use in last sexual intercourse with regular and occasional clients were above 93%. CONCLUSIONS: FSW show a decreasing trend in HIV, syphilis and chlamydia prevalence. Gonorrhoea prevalence in FSW and HRH did not decrease over time. HRH is a hard to engage population with low follow-up rates and high potential to act as a bridge population.

Damage-associated molecular pattern-activated neutrophil extracellular trap exacerbates sterile inflammatory liver injury.

UNLABELLED: Innate immunity plays a crucial role in the response to sterile inflammation such as liver ischemia/reperfusion (I/R) injury. The initiation of liver I/R injury results in the release of damage-associated molecular patterns, which trigger an innate immune and inflammatory cascade through pattern recognition receptors. Neutrophils are recruited to the liver after I/R and contribute to organ damage and innate immune and inflammatory responses. Formation of neutrophil extracellular traps (NETs) has been recently found in response to various stimuli. However, the role of NETs during liver I/R injury remains unknown. We show that NETs form in the sinusoids of ischemic liver lobes in vivo. This was associated with increased NET markers, serum level of myeloperoxidase-DNA complexes, and tissue level of citrullinated-histone H3 compared to control mice. Treatment with peptidyl-arginine-deiminase 4 inhibitor or DNase I significantly protected hepatocytes and reduced inflammation after liver I/R as evidenced by inhibition of NET formation, indicating the pathophysiological role of NETs in liver I/R injury. In vitro, NETs increase hepatocyte death and induce Kupffer cells to release proinflammatory cytokines. Damage-associated molecular patterns, such as High Mobility Group Box 1 and histones, released by injured hepatocytes stimulate NET formation through Toll-like receptor (TLR4)- and TLR9-MyD88 signaling pathways. After neutrophil depletion in mice, the adoptive transfer of TLR4 knockout or TLR9 knockout neutrophils confers significant protection from liver I/R injury with a significant decrease in NET formation. In addition, we found inhibition of NET formation by the peptidyl-arginine-deiminase 4 inhibitor and that DNase I reduces High Mobility Group Box 1 and histone-mediated liver I/R injury. CONCLUSION: Damage-associated molecular patterns released during liver I/R promote NET formation through the TLR signaling pathway. Development of NETs subsequently exacerbates organ damage and initiates inflammatory responses during liver I/R.

Mixing alternating copolymers containing fluorenyl groups with phospholipids to obtain Langmuir and Langmuir-Blodgett films.

The control of molecular architectures may be essential to optimize materials properties for producing luminescent devices from polymers, especially in the blue region of the spectrum. In this Article, we report on the fabrication of Langmuir-Blodgett (LB) films of polyfluorene copolymers mixed with the phospholipid dimyristoyl phosphatidic acid (DMPA). The copolymers poly(9,9-dioctylfluorene)-co-phenylene (copolymer 1) and poly(9,9-dioctylfluorene)-co-quaterphenylene) (copolymer 2) were synthesized via Suzuki reaction. Copolymer 1 could not form a monolayer on its own, but it yielded stable films when mixed with DMPA. In contrast, Langmuir monolayers could be formed from either the neat copolymer 2 or when mixed with DMPA. The surface pressure and surface potential measurements, in addition to Brewster angle microscopy, indicated that DMPA provided a suitable matrix for copolymer 1 to form a stable Langmuir film, amenable to transfer as LB films, while enhancing the ability of copolymer 2 to form LB films with enhanced emission, as indicated by fluorescence spectroscopy. Because a high emission was obtained with the mixed LB films and since the molecular-level interactions between the film components can be tuned by changing the experimental conditions to allow for further optimization, one may envisage applications of these films in optical devices such as organic light-emitting diodes (OLEDs).

Light emitting diodes containing Langmuir-Blodgett films of copolymer of a poly(p-phenylene-vinylene) derivative and poly(octaneoxide).

The properties of Langmuir and Langmuir-Blodgett (LB) films from a block copolymer with polyethylene oxide and phenylene-vinylene moieties are reported. The LB films were successfully transferred onto several types of substrates, with sufficient quality to allow for evaporation of a metallic electrode on top of the LB films to produce polymer light emitting diodes (PLEDs). The photoluminescence and electroluminescence spectra of the LB film and device were similar, featuring an emission at ca. 475 nm, from which we could infer that the emission mechanisms are essentially the same as in poly(p-phenylene) derivatives. Analogously to other PLEDs the current versus voltage characteristics of the LB-based device could be explained with the Arkhipov model according to which charge transport occurs among localized sites. The implications for nanotechnology of the level of control that may be achieved with LB devices will also be discussed.