Structure-Activity Effects in Self-Assembled Multivalent (SAMul) Polyanion Binding.

We have synthesized several self-assembled multivalent (SAMul) systems based on two parts; a hydrophobic part as the driving force for self-assembly, and a cationic hydrophilic part as the binding site for polyanions. A number of modified ligand displays were synthesized in order to investigate structure-activity relationship and their effects on self-assembly of such systems as well as their selectivities towards binding different polyanions (heparin and DNA). The first three systems were synthesized using unsaturated fatty acids (containing alkene groups), this resulted in different self-assembly abilities, in addition to different selectivities towards the biological polyanions (heparin and DNA). In an attempt to stabilize those systems, we cross-linked the alkene groups – however the binding did not improve. We modified the ligand binding sites, using different amines. This also resulted in different self-assembly preferences in addition to selectivities for binding heparin and DNA. Alternative approaches to stabilizing displays of heparin-binding ligands were tested using a branched scaffold with a high density of positive charges on the surface groups, gold nanoparticles and a ligand-polymer conjugate approach. Finally, a multicomponent approach was employed in this work. PEG-lipid additives, were introduced to our SAMul systems to test their impact on binding heparin and DNA. Adding PEG-lipids to our SAMul demonstrated that a simple uncharged species can have an influence on binding strength in the clinically relevant serum medium. In addition, the multicomponent approach was also performed on two compounds using a multi component MalB assay. This showed that this approach may in the future help rapidly identify mixtures of self-assembling components which have positive synergistic effects. In each study we have learned more about the structural impact of ligand designed display in polyanion binding – information which should prove useful in the future design of systems with clinical relevance

The Benefits of Cochlear Implants (CI) for the Educational Progress and Placement of Deaf Pupils at Primary School in Riyadh, Saudi Arabia

This research explores the benefits of cochlear implants (CI) for the educational progress and placement of deaf pupils at primary school in Saudi Arabia (SA). It also examines factors that might affect these benefits. This study provides an insight into the current situation of the educational status of deaf pupils with CIs in Riyadh in SA. Pilot study was conducted in order to examine the clarity of the research questions, instruments contents and structure. Amendments were made according to the findings of this pilot study. Participants comprised parents, teachers and clinicians’ perceptions, experiences and school academic report are involved by using semi structured questionnaires and interviews data. One hundred and ninety-six participants are from fifteen primary schools and one hospital. Key features highlighted advantages and disadvantages of CI, educational performance level of deaf pupils with CIs and compared to deaf pupils without CIs, availability of inclusion within mainstream classroom for deaf pupils with CIs and the factors might affect such educational progress and placements. The majority of parents, teachers and clinicians stated that CI has positive outcomes on the deaf child and benefits upon the educational progress. A substantial difference before and after surgery for better in improved hearing, educational achievement, language and speech, psychological and social aspects, more potential for inclusive education and greater independence were stated by parents, teachers and clinicians as advantages gained by their children/pupils/patients using CI. Analysis of data showed a notable discrepancy between participants’ experiences regarding the benefits of CI and the reality of the children educational progress and placements. The majority of pupils with CIs are studying in the year below the year that they are supposed to be at for their chronological age. Also, respect to the educational placements settings, the majority of pupils with CIs involved in this study are educated at units/classes attached to mainstream school but not within mainstream classroom where their hearing peers are. The study identified the factors affecting the benefits of CI, not only those that are related to the cochlear implants themselves, but also school-related factors and the role of administration and awareness, which seem to be dimensions that affect the outcome of CI in the Kingdom. Implications are discussed in view of findings.

Hepatitis B Virus Gene Mutations in Liver Diseases: A Report from New Delhi

The study was designed to characterize the surface, core promoter, precore/core region sequences for the presence of mutations in hepatitis B virus (HBV) associated with different liver diseases.567 HBV associated patients with different liver diseases were enrolled in this study. All samples were analyzed for HBV surface, core promoter, precore/core region mutations and genotypes using PCR and direct sequencing.HBV genotype D (72.8%) was the predominant type followed by genotype A (27.2%). The serum viral load of HBV was highest in HBsAg carriers group and lowest in patients with hepatocellular carcinoma. 17.9% patients with cirrhosis and 24.6% hepatocellular carcinoma cases were ADV-resistant with rtA181T/V mutations in the S-gene. A1896T was found more frequently in fulminant hepatic failure compared to acute viral hepatitis patients (p = 0.038). T1753V mutation was significantly higher in patients with cirrhosis of liver (34.6%) than in chronic hepatitis (18.9%) and hepatocellular carcinoma patients (21.2%; p = 0.001). T1762/A1764 mutation was observed in all the groups. C1914G core gene mutation was associated with the hepatocellular carcinoma (32.2%) compared to other groups. HBV genotype D predominated in comparison to genotype A. An increased frequency of precore mutation and BCP double mutations amongst the population studied was also observed.Mutations such as T1762/A1764, T1753V and C1914G were usually associated with advanced forms of liver disease and had an increased risk of HCC. The nucleotide variability in the basal core promoter and precore regions possibly plays a role in the progression of HBV disease. Prospective studies on the sequence variations of the preC/C region of the HBV genome and the molecular mechanisms in relation to progression of liver disease would aid in better understanding of the biological significance of HBV strains in India

The CAR-HEMATOTOX score identifies patients at high risk for hematological toxicity, infectious complications, and poor treatment outcomes following brexucabtagene autoleucel for relapsed or refractory MCL

Hematological toxicity; Infectious complicationsToxicidad hematológica; Complicaciones infecciosasToxicitat hematològica; Complicacions infecciosesCD19-directed CAR T-cell therapy with brexucabtagene autoleucel (brexu-cel) has substantially improved treatment outcomes for patients with relapsed/refractory mantle cell lymphoma (r/r MCL). Prolonged cytopenias and infections represent common and clinically relevant side effects. In this multicenter observational study, we describe cytopenias and infections in 103 r/r MCL patients receiving brexu-cel. Furthermore, we report associations between the baseline CAR-HEMATOTOX (HT) score and toxicity events, non-relapse mortality (NRM), and progression-free/overall survival (PFS/OS). At lymphodepletion, 56 patients were HTlow (score 0–1) while 47 patients were HThigh (score ≥2). The HThigh cohort exhibited prolonged neutropenia (median 14 vs. 6 days, p < .001) and an increased rate of severe infections (30% vs. 5%, p = .001). Overall, 1-year NRM was 10.4%, primarily attributed to infections, and differed by baseline HT score (high vs. low: 17% vs. 4.6%, p = .04). HThigh patients experienced inferior 90-day complete response rate (68% vs. 93%, p = .002), PFS (median 9 months vs. not-reached, p < .0001), and OS (median 26 months vs. not-reached, p < .0001). Multivariable analyses showed that high HT scores were independently associated with severe hematotoxicity, infections, and poor PFS/OS. In conclusion, infections and hematotoxicity are common after brexu-cel and contribute to NRM. The baseline HT score identified patients at increased risk of poor treatment outcomes.KR received a fellowship from the School of Oncology of the German Cancer Consortium (DKTK) and was funded by the Else Kröner Forschungskolleg (EKFK) within the Munich Clinician Scientist Program (MCSP). This work was supported by a grant within the Gilead Research Scholar Program (to KR, MS), the Bruno & Helene Jöster foundation (to KR, MS), and by a Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) research grant provided within the Sonderforschungbereich SFB-TRR 388/12021–452881907 and DFG research grant 451580403 (to MS). This work was in part supported by NCI/NIH P30CA076292. FLL is in part supported as a Clinical Scholar by the Leukemia and Lymphoma Society. The work was further supported by the Bavarian Elite Graduate Training Network (to MS), the Wilhelm-Sander Stiftung (to MS, project no. 2018.087.1), the Else-Kröner-Fresenius Stiftung (to MS), and the Bavarian Center for Cancer Research (BZKF)

Electrostatic binding of polyanions using self-assembled multivalent (SAMul) ligand displays-structure-activity effects on DNA/heparin binding

This paper reports that modifying the ligands in self-assembled multivalent (SAMul) displays has an impact on apparent binding selectivity towards two nanoscale biological polyanions-heparin and DNA. For the nanostructures assayed here, spermidine ligands are optimal for heparin binding but spermine ligands are preferred for DNA. Probing subtle differences in such nanoscale binding interfaces is a significant challenge, and as such, several experimental binding assays-competition assays and isothermal calorimetry-are employed to confirm differences in affinity and provide thermodynamic insights. Given the dynamic nature and hierarchical binding processes involved in SAMul systems, we employed multiscale modelling to propose reasons for the origins of polyanion selectivity differences. The modelling results, when expressed in thermodynamic terms and compared with the experimental data, suggest that DNA is a shape-persistent polyanion, and selectivity originates only from ligand preferences, whereas heparin is more flexible and adaptive, and as such, actively reinforces ligand preferences. As such, this study suggests that inherent differences between polyanions may underpin subtle binding selectivity differences, and that even simple electrostatic interfaces such as these can have a degree of tunability, which has implications for biological control and regulation on the nanoscale

Neonatal retroauricular cellulitis as an indicator of group B streptococcal bacteremia: a case report

<p>Abstract</p> <p>Introduction</p> <p>The relation between cellulitis and Group B streptococcus infection in newborns and small infants was first reported during the early 1980s and named cellulitis-adenitis syndrome. We report a case of a neonate with cellulitis-adenitis syndrome in an unusual location (retroauricular).</p> <p>Case presentation</p> <p>A 21-day-old Caucasian female infant was brought to the emergency department with fever, irritability and a decreased appetite. Physical examination revealed erythema and painful, mild swelling in the right retroauricular region. The blood count and C-reactive protein level were normal. She was treated with ceftriaxone. The fever and irritability were resolved after 24 hours, and the cellulitis was clearly reduced after two days of hospitalization. Blood culture yielded Group B streptococcus.</p> <p>Conclusion</p> <p>A thorough evaluation must be done, and lumbar punctures for infants with cellulitis must be considered. We emphasize the lack of data about acute phase reactants to predict bacteremia and meningitis and to adjust the duration of parenteral antibiotic therapy to address this syndrome.</p

Multi-component hybrid hydrogels – understanding the extent of orthogonal assembly and its impact on controlled release

This paper reports self-assembled multi-component hybrid hydrogels including a range of nanoscale systems and characterizes the extent to which each component maintains its own unique functionality, demonstrating that multi-functionality can be achieved by simply mixing carefully-chosen constituents. Specifically, the individual components are: (i) pH-activated low-molecular-weight gelator (LMWG) 1,3;2,4-dibenzylidenesorbitol-4′,4′′-dicarboxylic acid (DBS–COOH), (ii) thermally-activated polymer gelator (PG) agarose, (iii) anionic biopolymer heparin, and (iv) cationic self-assembled multivalent (SAMul) micelles capable of binding heparin. The LMWG still self-assembles in the presence of PG agarose, is slightly modified on the nanoscale by heparin, but is totally disrupted by the micelles. However, if the SAMul micelles are bound to heparin, DBS–COOH self-assembly is largely unaffected. The LMWG endows hybrid materials with pH-responsive behavior, while the PG provides mechanical robustness. The rate of heparin release can be controlled through network density and composition, with the LMWG and PG behaving differently in this regard, while the presence of the heparin binder completely inhibits heparin release through complexation. This study demonstrates that a multi-component approach can yield exquisite control over self-assembled materials. We reason that controlling orthogonality in such systems will underpin further development of controlled release systems with biomedical applications

Clinical and biochemical characteristics of people experiencing post-coronavirus disease 2019-related symptoms: A prospective follow-up investigation

BackgroundPost-acute coronavirus disease 2019 (COVID-19) syndrome, also known as long COVID, is a prolonged illness after the acute phase of COVID-19. Hospitalized patients were known to have persisting symptoms of fatigue, headache, dyspnea, and anosmia. There is a need to describe the characteristics of individuals with post-COVID-19 symptoms in comparison to the baseline characteristics.PurposeTo investigate the clinical and biochemical characteristics of people who recovered from COVID-19 after 6 months of discharge from the hospital.MethodsThis was a prospective follow-up investigation of hospitalized and discharged COVID-19 patients. Adult patients admitted to King Saud University Medical City, Riyadh, Saudi Arabia, with laboratory-confirmed COVID-19 and discharged were recruited. The baseline demographic information, comorbidities, vital signs and symptoms, laboratory parameters, COVID-19 therapy, and outcomes were collected from the medical records. Blood samples were collected for cytokines estimation. A detailed interview about signs and symptoms was undertaken during the follow-up.ResultsHalf of the followed-up people reported experiencing at least one of the COVID-19-related symptoms. The mean blood pressure was found higher in follow-up. People with the symptoms were characterized by low lymphocyte count, lower serum calcium levels, and hyperglycemia compared to people without any post-COVID-19 symptoms. Cytokines IL-8, VEGF, and MCP-1 were higher in people with the most frequent symptoms.ConclusionPeople with post-COVID-19 symptoms were characterized by lower lymphocyte count, lower serum calcium levels, and hyperglycemia compared to people without symptoms. Individuals with the most frequent post-COVID-19 symptoms had higher baseline pro-inflammatory, chemotactic, and angiogenic cytokines

Severe hematotoxicity after CD19 CAR-T therapy is associated with suppressive immune dysregulation and limited CAR-T expansion

Prolonged cytopenias after chimeric antigen receptor (CAR) T cell therapy are a significant clinical problem and the underlying pathophysiology remains poorly understood. Here, we investigated how (CAR) T cell expansion dynamics and serum proteomics affect neutrophil recovery phenotypes after CD19-directed CAR T cell therapy. Survival favored patients with "intermittent" neutrophil recovery (e.g., recurrent neutrophil dips) compared to either "quick" or "aplastic" recovery. While intermittent patients displayed increased CAR T cell expansion, aplastic patients exhibited an unfavorable relationship between expansion and tumor burden. Proteomics of patient serum collected at baseline and in the first month after CAR-T therapy revealed higher markers of endothelial dysfunction, inflammatory cytokines, macrophage activation, and T cell suppression in the aplastic phenotype group. Prolonged neutrophil aplasia thus occurs in patients with systemic immune dysregulation at baseline with subsequently impaired CAR-T expansion and myeloid-related inflammatory changes. The association between neutrophil recovery and survival outcomes highlights critical interactions between host hematopoiesis and the immune state stimulated by CAR-T infusion