Upper-level inter-disciplinary microbiology CUREs increase student's scientific self-efficacy, scientific identity, and self-assessed skills.

Course-based undergraduate research experiences (CUREs) provide opportunities for undergraduate students to engage in authentic research and generally increase the participation rate of students in research. Students' participation in research has a positive impact on their science identity and self-efficacy, both of which can predict integration of students in Science, Technology, Engineering, and Math (STEM), especially for underrepresented students. The main goal of this study was to investigate instructor-initiated CUREs implemented as upper-level elective courses in the Biomedical Sciences major. We hypothesized that these CUREs would (i) have a positive impact on students' scientific identity and self-efficacy and (ii) result in gains in students' self-assessed skills in laboratory science, research, and science communication. We used Likert-type surveys developed by Estrada et al. (14) under the Tripartite Integration Model of Social Influence to measure scientific identity, self-efficacy, and scientific value orientation. When data from all CUREs were combined, our results indicate that students' self-efficacy and science identity significantly increased after completion. Students' self-assessment of research and lab-related skills was significantly higher after completion of the CUREs. We also observed that prior to participation in the CUREs, students' self-assessment of molecular and bioinformatic skills was low, when compared with microbiological skills. This may indicate strengths and gaps in our curriculum that could be explored further.

CURE on yeast genes of unknown function increases students' bioinformatics proficiency and research confidence.

Course-based undergraduate research experiences (CUREs) can reduce barriers to research opportunities while increasing student knowledge and confidence. However, the number of widely adopted, easily transferable CUREs is relatively small. Here, we describe a CURE aimed at determining the function of poorly characterized Saccharomyces cerevisiae genes. More than 20 years after sequencing of the yeast genome, nearly 10% of open reading frames (ORFs) still have at least one uncharacterized Gene Ontology (GO) term. We refer to these genes as "ORFans" and formed a consortium aimed at assigning functions to them. Specifically, over 70 faculty members attended summer workshops to learn the bioinformatics workflow and basic laboratory techniques described herein. Ultimately, this CURE was adapted for implementation at 34 institutions, resulting in over 1,300 students conducting course-based research on ORFans. Pre-/post-tests confirmed that students gained both (i) an understanding of gene ontology and (ii) knowledge regarding the use of bioinformatics to assign gene function. After using these data to craft their own hypotheses, then testing their predictions by constructing and phenotyping deletion strains, students self-reported significant gains in several areas, including computer modeling and exposure to a project where no one knows the outcome. Interestingly, most net gains self-reported by ORFan Gene Project participants were greater than published findings for CUREs assessed with the same survey instrument. The surprisingly strong impact of this CURE may be due to the incoming lack of experience of ORFan Project participants and/or the independent thought required to develop testable hypotheses from complex data sets.

A framework for leveraging network course-based undergraduate research experience (CURE) faculty to develop, validate, and administer an assessment instrument.

Over the last several years, nationally disseminated course-based undergraduate research experiences (CUREs) have emerged as an alternative to developing a novel CURE from scratch, but objective assessment of these multi-institution (network) CUREs across institutions is challenging due to differences in student populations, instructors, and fidelity of implementation. The time, money, and skills required to develop and validate a CURE-specific assessment instrument can be prohibitive. Here, we describe a co-design process for assessing a network CURE [the Prevalence of Antibiotic Resistance in the Environment (PARE)] that did not require support through external funding, was a relatively low time commitment for participating instructors, and resulted in a validated instrument that is usable across diverse PARE network institution types and implementation styles. Data collection efforts have involved over two dozen unique institutions, 42 course offerings, and over 1,300 pre-/post-matched assessment record data points. We demonstrated significant student learning gains but with small effect size in both content and science process skills after participation in the two laboratory sessions associated with the core PARE module. These results show promise for the efficacy of short-duration CUREs, an educational research area ripe for further investigation, and may support efforts to lower barriers for instructor adoption by leveraging a CURE network for developing and validating assessment tools.

Circulating HBV RNA and hepatitis B core-related antigen trajectories in persons with HIV/HBV coinfection and HBsAg loss on tenofovir therapy.

BACKGROUND: We evaluated long-term trajectories of circulating hepatitis B virus (HBV)-RNA and hepatitis B core-related antigen (HBcrAg) in persons with and without hepatitis B surface antigen (HBsAg) loss during tenofovir therapy in the Swiss HIV Cohort Study. METHODS: We included 29 persons with HIV (PWH) with HBsAg loss and 29 matched PWH without loss. We compared HBV-RNA and HBcrAg decline and assessed the cumulative proportions with undetectable HBV-RNA and HBcrAg levels during tenofovir therapy using Kaplan-Meier estimates. RESULTS: HBsAg loss occurred after a median of 4 years (IQR 1 - 8). All participants with HBsAg loss achieved suppressed HBV-DNA and undetectable HBV-RNA preceding undetectable qHBsAg levels, whereas 79% achieved negative HBcrAg. In comparison, 79% of the participants without HBsAg loss achieved undetectable HBV-RNA and 48% negative HBcrAg. After two years on tenofovir, an HBV RNA decline ≥1 log10 copies/ml had 100% sensitivity and 36.4% specificity for HBsAg loss, whereas an HBcrAg decline ≥1 log10 U/ml had 91.0% sensitivity and 64.5% specificity. CONCLUSIONS: HBV-RNA suppression preceded undetectable qHBsAg levels, and had high sensitivity but low specificity for HBsAg loss during tenofovir therapy in PWH. HBcrAg remained detectable in approximately 20% of persons with, and 50% of persons without HBsAg loss.

Indicators of cure for women living after uterine and ovarian cancers: a population-based study.

This study aims to estimate long-term survival, cancer prevalence, and several cure indicators for Italian women with gynaecological cancers. Thirty-one cancer registries, representing 47% of the Italian female population, were included. Mixture cure models were used to estimate Net Survival (NS), Cure Fraction, Time To Cure (5-year conditional NS>95%), Cure Prevalence (women who will not die of cancer), and Already Cured (living longer than Time to Cure). In 2018, 0.4% (121,704) of Italian women were alive after corpus uteri cancer, 0.2% (52,551) after cervical, and 0.2% (52,153) after ovarian cancer. More than 90% of patients with uterine cancers and 83% with ovarian cancer will not die from their neoplasm (Cure Prevalence). Women with gynaecological cancers have a residual excess risk of death <5% after 5 years since diagnosis. The Cure Fraction was 69% for corpus uteri, 32% for ovarian, and 58% for cervical cancer patients. Time To Cure was ≤10 years for women with gynaecological cancers aged <55 years. 74% of patients with cervical cancer, 63% with corpus uteri cancer, and 55% with ovarian cancer were Already Cured. These results will contribute to improving follow-up programs for women with gynaecological cancers and supporting efforts against discrimination of already cured ones.

Advancing HIV cure research in low- and middle-income countries requires empowerment of the next generation of scientists.

While low- and middle-income countries (LMICs), especially in Southern and Eastern Africa, bear the largest burden of the HIV globally, investigators working on the front lines in these regions are leading a limited number of research efforts, particularly related to HIV cure. Conducting HIV cure research in high-burden HIV LIMCs provides an unparalleled opportunity to formulate innovative research strategies, design trials tailored to the local context, evaluate clinical outcomes within key and vulnerable populations, meaningful involvement of stakeholders, and to shape policies in areas where HIV prevention and cure interventions can yield the most significant impact. Further, the high prevalence of infection, with varied HIV strains affecting large diverse populations, creates a unique environment for studies that would not be feasible in any other part of the world. This underscores the critical importance of addressing obstacles to unlock the full potential of research efforts in these regions. In this viewpoint, we identify significant challenges facing early career investigators in LMICs, particularly in Africa, that hinder their full engagement in HIV cure research. Drawing examples from the International AIDS Society's Research-for-Cure Academy, we provide practical recommendations to overcome barriers that include limited access to funding, effective mentors, educational and career development opportunities, coupled with inadequate investment in infrastructure that contribute towards the limited number of investigators from high-burden HIV LIMCs who are spearheading cutting-edge cure research. Addressing these challenges is crucial to empower investigators who possess unique insights and expertise, and who are well positioned to lead HIV cure-related research efforts. We acknowledge and welcome initiatives that promote capacity building and knowledge exchange between early-career investigators in LMICs and their peers and scientific leaders from high-income countries (HICs). Prioritizing investment in global collaboration and partnership will play a pivotal role in empowering the next generation of African scientists and clinicians. To expedite advancements of cure-related strategies that will be effective in high-burden HIV LMICs, we endorse the sustainable expansion of these pivotal initiatives in these regions, to enhance their effectiveness and hasten progress in the pursuit of a global HIV cure.

Occult hepatitis B virus infection and current perspectives on global WHO 2030 eradication.

The current World Health Organization (WHO) Hepatitis Elimination Strategy suffers from lack of a target for diagnosing or expunging occult HBV infection. A sizable segment of the global population has an undetected HBV infection, particularly the high-risk populations and those residing in countries like India with intermediate endemicity. There is growing proof that people with hidden HBV infection can infect others, and that these infections are linked to serious chronic hepatic complications, especially hepatocellular carcinoma. Given the current diagnostic infrastructure in low-resource settings, the WHO 2030 objective of obliterating hepatitis B appears to be undeniably challenging to accomplish. Given the molecular basis of occult HBV infection strongly linked to intrahepatic persistence, patients may inexplicably harbour HBV genomes for a prolonged duration without displaying any pronounced clinical or biochemical signs of liver disease, and present histological signs of moderate degree necro-inflammation, diffuse fibrosis, and hence the international strategy to eradicate viral hepatitis warrants inclusion of occult HBV infection.

Airway collapse hinders recovery in bronchoscopy therapy for postintubation tracheal stenosis patients.

BACKGROUND: Expiratory central airway collapse (ECAC) following postintubation airway stenosis (PITS) is a rare phenomenon. The impact of airway malacia and collapse on the prognosis and the success rate of bronchoscopic interventional therapy in patients with PITS had been inadequately investigated. OBJECTIVE: The aim of this research was to assess the influence of airway malacia and collapse on the efficacy of bronchoscopic interventional therapy in patients with PITS. DESIGN: This retrospective analysis examined the medical documentation of individuals diagnosed with PITS who underwent bronchoscopic intervention at the tertiary interventional pulmonology center of Emergency General Hospital from 2014 to 2021. MAIN OUTCOME MEASURES: Data pertaining to preoperative, perioperative, and postoperative stages were documented and subjected to analysis. RESULTS: The patients in malacia and collapse group (MC group) exhibited a higher frequency of perioperative complications, including intraoperative hypoxemia, need for reoperation within 24 h, and postoperative intensive care unit admission rate (P < 0.05, respectively). Meanwhile, patients in group MC demonstrated significantly worse postoperative scores (higher mMRC score and lower KPS score) compared to those in pure stenosis group (P < 0.05, respectively), along with higher degrees of stenosis after treatment and a lower success rate of bronchoscopic intervention therapy cured (P < 0.05, respectively). Pearson analysis results showed that these terms were all significantly correlated with the occurrence of airway malacia and collapse in the airway (P < 0.05, respectively). CONCLUSION: The presence of malacia or collapse in patients with PITS was associated with increased perioperative complications following bronchoscopic interventional therapy, and significantly reduced the long-term cure rate compared to patients with pure tracheal stenosis. Trial registration Chinese Clinical Trial Registry on 06/12/2021. REGISTRATION NUMBER: ChiCTR2100053991.

Death after cure: mortality among pulmonary tuberculosis survivors in rural Uganda.

OBJECTIVE: To determine the incidence of mortality and its predictors among pulmonary TB (PTB) survivors treated at a rural Ugandan tertiary hospital. METHODS: We conducted a retrospective chart review of data between 2013 and 2023. We included all people that met the WHO's definition of tuberculosis cure and traced them or their next of kin to determine vital status (alive/deceased). We estimated the cumulative incidence of mortality per 1,000 population, crude all-cause mortality rate per 1,000 person-years, and median years of potential life lost (YPLL) for deceased individuals. Using Cox proportional hazard models, we investigated predictors of mortality. RESULTS: Of 334 PTB survivors enrolled, 38 (11.4%) had died. The cumulative incidence of all-cause mortality was 113.7 per 1,000 population, and the crude all-cause mortality rate was 28.5 per 1,000 person-years. The median YPLL for deceased individuals was 23.8 years (IQR: 9.6-32.8). Hospitalization (aHR: 4.3, 95% CI: 1.1-16.6) and unemployment (aHR: 7.04, 95% CI: 1.5-31.6) at TB treatment initiation predicted mortality. CONCLUSION: PTB survivors experience post high mortality rates after TB cure. Survivors who were hospitalized and unemployed at treatment initiation were more likely to die after cure. Social protection measures and long-term follow-up of previously hospitalized patients could improve the long-term survival of TB survivors.

Personalized, Precision Medicine to Cure Alzheimer's Dementia: Approach #1.

The goal of the treatment for Alzheimer's dementia (AD) is the cure of dementia. A literature review revealed 18 major elements causing AD and 29 separate medications that address them. For any individual with AD, one is unlikely to discern which major causal elements produced dementia. Thus, for personalized, precision medicine, all causal elements must be treated so that each individual patient will have her or his causal elements addressed. Twenty-nine drugs cannot concomitantly be administered, so triple combinations of drugs taken from that list are suggested, and each triple combination can be administered sequentially, in any order. Ten combinations given over 13 weeks require 2.5 years, or if given over 26 weeks, they require 5.0 years. Such sequential treatment addresses all 18 elements and should cure dementia. In addition, any comorbid risk factors for AD whose first presence or worsening was within ±1 year of when AD first appeared should receive appropriate, standard treatment together with the sequential combinations. The article outlines a randomized clinical trial that is necessary to assess the safety and efficacy of the proposed treatments; it includes a triple-drug Rx for equipoise. Clinical trials should have durations of both 2.5 and 5.0 years unless the data safety monitoring board (DSMB) determines earlier success or futility since it is uncertain whether three or six months of treatment will be curative in humans, although studies in animals suggest that the briefer duration of treatment might be effective and restore defective neural tracts.

Acemannan-containing bioactive resin modified glass ionomer demonstrates satisfactory physical and biological properties.

Background/purpose: Resin-modified glass ionomers (RMGIs) have been recommended as liner and cement to provide the teeth with mechanical support, a chemical barrier, and thermal insulation. Acemannan, the main polysaccharide extracted from Aloe vera, is a promising inductive material in vitro and in vivo. This study aimed to develop acemannan-containing bioactive resin-modified glass ionomers (RMGIs). Materials and methods: Acemannan (3%, 5%, and 10%) was added to the three types of RMGIs (RU-HBM1/Fuji II LC/Vitrebond) to generate 3%, 5%, and 10% aceRMGIs (aceRU/aceFuji/aceVB). The materials were evaluated for depth of cure/flexural strength/cumulative fluoride ion release. Cell viability and vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) secretion were determined using MTT/apoptosis/necrosis assays, and ELISA kits, respectively. RMGI without acemannan were used as controls. Results: The aceRMGIs met the ISO requirements for depth of cure and flexural strength. Adding 10% acemannan increased the cumulative fluoride release in the RU and FJ groups, but slightly decreased it in the VB group (P < 0.05). The MTT assay revealed 10% aceRU and all aceFJ groups significantly increased cell viability compared with each control group (P < 0.05). Apoptosis/necrosis assay showed the biocompatibility of all aceRMGIs. Adding acemannan to RMGIs significantly induced VEGF expression in a dose dependent manner while 5% and 10% aceRU significantly induced BMP-2 expression compared with RU group (P < 0.05). Conclusion: We conclude that 5-10% acemannan in RMGI is the optimal concentration based on its physical properties and ability to induce pulp cell proliferation and growth factor secretion.

Dermoscopy of Fixed Cutaneous Sporotrichosis With a Follow-Up Till Cure: A Case Report.

Fixed cutaneous sporotrichosis (FCS) is a rare and chronic infection. Its diagnosis requires a high degree of suspicion. The data on its dermoscopy and follow-up is limited in the literature. We herein report one such case with a follow-up till cure along with its dermoscopy to establish certain specific features that may be used to ascertain the response to treatment for this chronic infection and its prognosis. We found only three such cases following an extensive review of the literature, and this case emphasizes the importance of dermoscopy in recent times as the history, swab cultures, and smears may be misleading at times due to the chronic and long-standing nature of the condition.

Efficacy of 400 mg albendazole against soil-transmitted helminthes among Salgy Primary School Children, Dembia district, Northwest Ethiopia, 2020. "Uncontrolled experimental study".

Background and Aims: Soil-transmitted helminths are one of the most prevalent causes of both intellectual and physical disability in the world. Albendazole (ALB) is a drug recommended for mass treatment of the high burden of soil-transmitted helminths in schoolchildren, particularly in developing countries. However, some researchers have reported that the efficacy of albedazole against soil-transmitted helminths is inconsistent. Monitoring the programs is crucial to evaluating the effectiveness of 400 mg of ALB against soil-transmitted helminths, as well as any changes in its therapeutic efficacy. Thus, the purpose of this study was to evaluate ALB effectiveness in treating soil-transmitted helminthes in Salgy Primary School Children. Methods: An uncontrolled experimental study was conducted at Salgy Primary School Children, Northwest Ethiopia, from March to May 2020. A total of 439 schoolchildren were enrolled and screened for soil-transmitted helminths by stratified proportionate systematic random sampling to get 228 positive schoolchildren. Students in grades one through eight were grouped based on their educational attainment. Using the Kato-Katz thick smear technique, the selected stool sample collected from school children was examined using the Kato-Katz thick smear technique to determine the cure and egg reduction rates. The statistical package for social science software, version 20, was used to analyze the data. To determine the relationship between CR (cure rate) and ERR (egg reduction rate) by age, a chi-square test (X 2) was employed and significance was considered at A 95% confidence interval and p Value (p < 0.05). Results: A 400 mg single dosage of ALB showed a 99.35% CR and a 97.30% egg reduction rate against Ascaris lumibricoides. Additionally, a 400 mg dose of ALB showed a 95.75% CR and an 82.07% egg reduction rate, suggesting questionable effectiveness against hookworm infections. Trichuris trichiura showed a decreased efficacy, with a 43.53% CR and a 23.12% egg reduction rate. Conclusion: A single dose of 400 mg ALB is effective (satisfactory), doubtful, and unsatisfactory against Ascaris lumbricoides, hookworm, and T. trichiura infections, respectively. Further studies using different brands, doses, and routes will be needed to treat hookworm and T. trichiura infections successfully by using a larger sample size.

The power of light - From dental materials processing to diagnostics and therapeutics.

Harnessing the power of light and its photonic energy is a powerful tool in biomedical applications. Its use ranges from biomaterials processing and fabrication of polymers to diagnostics and therapeutics. Dental light curable materials have evolved over several decades and now offer very fast (≤ 10 s) and reliable polymerization through depth (4-6 mm thick). This has been achieved by developments on two fronts: (1) chemistries with more efficient light absorption characteristics (camphorquinone [CQ], ~30 L mol-1 cm1 [ʎmax 470 nm]; monoacylphosphine oxides [MAPO], ~800 L mol-1 cm-1 [ʎmax 385 nm]; bisacylphosphine oxide [BAPO], ~1,000 L mol-1 cm-1 [ʎmax 385 nm]) as well mechanistically efficient and prolonged radical generation processes during and after light irradiation, and; (2) introducing light curing technologies (light emitting diodes [LEDs] and less common lasers) with higher powers (≤ 2 W), better spectral range using multiple diodes (short: 390-405 nm; intermediate: 410-450 nm; and long: 450-480 nm), and better spatial power distribution (i.e. homogenous irradiance). However, adequate cure of materials falls short for several reasons, including improper selection of materials and lights, limitations in the chemistry of the materials, and limitations in delivering light through depth. Photonic energy has further applications in dentistry which include transillumination for diagnostics, and therapeutic applications that include photodynamic therapy, photobiomodulation, and photodisinfection. Light interactions with materials and biological tissues are complex and it is important to understand the advantages and limitations of these interactions for successful treatment outcomes. This article highlights the advent of photonic technologies in dentistry, its applications, the advantages and limitations, and possible future developments.

The Effect of Aging on Artificial Saliva at Different pH Values on the Color Stability of New Generation Denture Base Materials.

STATEMENT OF PROBLEM: New-generation denture base materials are used successfully in denture fabrication; however, the effect of saliva pH change on the color stability of materials is unknown. PURPOSE: The purpose of this in vitro study is to evaluate the color stability of new-generation denture base materials after immersion in artificial saliva with different pH values (3,7,14). MATERIAL AND METHODS: Disc-shaped samples (Ø 10 mm x 2 mm) were prepared from three different denture base materials (1 pre-polymerized polymethylmethacrylate [PMMA], 1 graphene-reinforced PMMA, and heat-cure polymethyl methacrylate resin) (n=10). After polishing, color coordinates were measured using a PCE-CSM 5 colorimeter programmed in the CIE system (L* a* b*). The samples were kept in artificial saliva at different pH values and 37°C for 21 days. At the end of 21 days, color coordinates were measured again. The suitability of the measurements for a normal distribution was examined with the Kolmogro-Smirnov test. Whether color measurements obtained at different pH levels differed according to groups was examined with the Kruskal-Wallis test. The correlation between the CIEDE2000 and CIELab color difference formulas was examined by correlation analysis. RESULTS: The highest color difference occurred in heat-cure samples at pH 3 (p<0.001). The color difference at different pH values was least observed in pre-polymerized PMMA samples. Significant color differences occurred in the graphene-reinforced pre-polymerized PMMA group at pH 7 (p<0.001). CONCLUSIONS: It was observed that color differences occurred in all groups. Dentures made of new-generation CAD/CAM PMMA, which are less exposed to color differences, can be recommended for elderly patients with systemic diseases who are frequently exposed to pH changes in the oral cavity. CLINICAL IMPLICATIONS: Color differences on denture surfaces over time negatively affect aesthetics. Since pH changes cause changes on the prosthesis surface, it may be recommended for these patients to fabricate dentures from new-generation CAD/CAM PMMA resins, which are less deformable.

Comparison between intrauterine application of an antibiotic and an herbal product to treat clinical endometritis in dairy cattle - A randomized multicentre field study.

Uterine diseases are main indications for antibiotic use in dairy cows. To test a non-antibiotic treatment option, we compared the effect of an intrauterine cephapirin (Metricure®; cefapirin benzathin 500 mg per dosis; CEPH) with an intrauterine applied herbal product (25 ml of EucaComp® PlantaVet containing alcoholic extracts of Calendula officinalis L., Mellissa officinalis L., Origanum majorana L. and Eucalyptus globulus Labill. (EUC)) on the clinical cure of endometritis. Examinations of 816 cows between 21 and 35 days after calving were performed and cases of clinical endometritis (n = 169) were included. Diagnosis based on a scoring system for vaginal discharge. Study animals were randomly assigned to one of two treatment groups and treated immediately. After excluding animals with incomplete datasets, 136 cows (EUC: n = 61; CEPH: n = 75) remained for the final analysis. In total, 64% (EUC: 61%, CEPH: 67%) of analysed endometritis cases were considered as clinically cured 14 ± 2 days after the first treatment, 15% stayed uncured after the application of a maximum of two consecutive treatments, leading to an overall clinical cure rate of 85% (EUC: 82%, CEPH: 88%). No statistically difference in clinical cure rates could be observed between both treatment groups nor 14 ± 2 days after the first treatment (p = 0.956) neither regarding the overall cure rate (p = 0.923). In conclusion, the clinical cure of dairy cows' endometritis after the intrauterine application of the herbal product was non-inferior to the intrauterine application of the antibiotic cephapirin. These results could contribute to reduce the antimicrobial use in the daily veterinary routine treatment of endometritis.

Cost-effectiveness analysis 3L of axicabtagene ciloleucel vs tisagenlecleucel and lisocabtagene maraleucel in Japan.

Aim: Cost-effectiveness analysis (CEA) was performed to compare axicabtagene ciloleucel (axi-cel) with tisagenlecleucel (tisa-cel) and lisocabtagene (liso-cel) for treatment of relapsed or refractory large B-cell lymphoma in adult patients after ≥2 lines of therapy in Japan. Materials & methods: Cost-effectiveness analysis was conducted using the partition survival mixture cure model based on the ZUMA-1 trial and adjusted to the JULIET and TRANSCEND trials using matching-adjusted indirect comparisons. Results & conclusion: Axi-cel was associated with greater incremental life years (3.13 and 2.85) and incremental quality-adjusted life-years (2.65 and 2.24), thus generated lower incremental direct medical costs (-$976.29 [-¥137,657] and -$242.00 [-¥34,122]), compared with tisa-cel and liso-cel. Axi-cel was cost-effective option compared with tisa-cel and liso-cel from a Japanese payer's perspective.

Enhancing Rubber Vulcanization Cure Kinetics: Lowering Vulcanization Temperature by Addition of MgO as Co-Cure Activator in ZnO-Based Cure Activator Systems.

Vulcanization is a chemical modification of rubber that requires a considerable amount of thermal energy. To save thermal energy, the kinetics of rubber vulcanization should be improved. In this article, the curing properties of rubber vulcanization are thoroughly investigated using the moving die rheometer (MDR) technique. To enhance the kinetics in different stages of ZnO-based sulfur vulcanization systems, small amounts of MgO were added. The results revealed that the small amount of 1 to 2 phr (per hundred grams of rubber) of MgO in the controlled 5 phr ZnO-based curing systems can significantly improve the curing kinetics. For example, the optimum curing time of 1 phr MgO added to the 5 phr ZnO-containing semi-efficient vulcanization system at different temperatures was more than half that of the controlled 5 phr ZnO-only compound. While maintaining a similar rate of vulcanization, the vulcanization temperature can be reduced by up to 20 °C by using MgO as a co-cure activator, which exhibits similar or better rheometric mechanical properties compared to the controlled compounds. With the addition of MgO as a co-cure activator, the vulcanization reactions become very fast, enabling vulcanization to be completed, even at the boiling point of water (100 °C) with an affordable curing time (<1 h). By reducing the vulcanization temperature, the scorch safety time can be enhanced in the ZnO/MgO-based binary cure activator-containing vulcanizates. Overall, MgO could be a potential candidate as a co-cure activator with ZnO for the vulcanization of rubber, offering better economical and eco-friendly methods.

The Use of Tenofovir Disoproxil Fumarate in the Management of eAg-Negative Chronic Hepatitis B Infection.

Background/Objectives: Currently, there are insufficient data to recommend the treatment of patients with hepatitis B e antigen (HBeAg)-negative chronic infection who have normal ALT and low HBV DNA, since the prognosis is generally regarded as favorable. The aim of this pilot study was to determine whether the use of tenofovir disoproxil fumarate (TDF) 300 mg/day for 3 years was able to achieve functional cure (HBsAg loss) and HBsAg seroconversion in HBeAb-positive individuals. Methods: Fifty patients not on antiviral therapy (40% men, mean age 48.9 ± 10.9 years, 84% Asians) with minimal fibrosis were enrolled. Results: TDF reduced HBV DNA significantly to undetectable levels after 6 months. Overall, 48.3% of inactive carriers (baseline HBV DNA < 2000 IU/mL) remained HBV DNA negative 6 months after treatment withdrawal, which was significantly higher than the 5.6% in those who were not inactive carriers (baseline HBV DNA ≥ 2000 IU/mL) (p = 0.003). The HBsAg levels did not drop throughout the study period with no difference between inactive carriers versus those who were not. Five inactive carriers achieved functional cure, but none of these were amongst those who were not inactive carriers. No renal dysfunction or ALT flare on treatment withdrawal was observed. Conclusions: TDF could potentially be used to induce functional cure in patients who are inactive carriers with normal ALT, low HBV DNA and without advanced fibrosis.

Antiviral Therapy of Chronic Hepatitis B Virus between Present and Future.

Background/Objectives: The objective of this study was to analyze the results of clinical trials regarding long-term antiviral therapies in chronic hepatitis with HBV to compare current therapeutic protocols and to analyze the results of preliminary studies with new antiviral therapies for HBV. Methods: Clinical studies and meta-analyses from PubMed, Google Scholar, and Research Gate from 2011 to 2024 were analyzed on patients undergoing chronic antiviral therapy for HBV, and a retrospective observational study performed in our clinic on a group of 76 patients undergoing chronic therapy with entecavir was presented. Also, a summary of the results of preliminary studies with various innovative antiviral molecules for HBV was performed. Results: The results of extensive clinical trials reveal that current therapies for chronic HBV are well tolerated and maintain good viral suppression if the patient is adherent to therapy. Innovative therapies aim to eliminate HBsAg and, thus, significantly shorten the duration of treatment, and the preliminary results of the studies are promising. Conclusions: Being an asymptomatic condition that requires life-long therapy, adherence to therapy is a real problem. Also, the risk of decompensation of liver cirrhosis and adenocarcinoma remains important in these patients. Future research is needed to perfect some antiviral therapy schemes that shorten the treatment period but also decrease the rate of progression towards decompensated cirrhosis and liver adenocarcinoma.