Retraction notice to "4-Carboxyphenyl as efficient donor group in nano Zn-porphyrin for dye sensitized solar cells" [Environ. Res. 251(2024)118704

SUMMARYGlutamate is an essential building block and the most important amino group donor in the cell. The reactions involved in synthesis and degradation link carbon to nitrogen metabolism. The synthesis and activity of the enzymes catalyzing these reactions must, therefore, be precisely regulated. In the Gram-positive model bacterium Bacillus subtilis, glutamate is exclusively synthesized by the combined action of the glutamine synthetase (GS) and the glutamate synthase (GOGAT). The GS catalyzes the ATP-dependent assimilation of ammonium, resulting in the formation of glutamine. Glutamine is converted together with 2-oxoglutarate by the GOGAT into glutamate, which can be used either for further assimilation of ammonium, or as a building block, or amino group donor. The glutamate dehydrogenases (GDHs) GudB and RocG are strictly devoted to glutamate degradation. In recent years, exciting new observations have been made in nitrogen metabolism in B. subtilis. The GS, GOGAT, and the GDHs are multifunctional enzymes, with the GS and GDHs acting as trigger enzymes in the control of gene expression, in addition to their enzymatic activity. The glutamate-synthesizing GOGAT acts as a counter enzyme, inactivating the major GDH GudB to prevent a futile cycle. In this review, we intend to summarize the current state of knowledge about nitrogen metabolism in B. subtilis and discuss open questions that need to be answered in the future.

Ribozymes for site-specific RNA modification provide an elegant approach for the installation of diverse functional groups, fluorophores, affinity tags, or crosslinkers at defined positions within an RNA of interest. There is increasing interest in expanding the ribozyme toolbox, since recently reported in vitro selected ribozymes have been mostly limited to labeling at adenosine sites, either by alkylation of the nucleobase or phosphodiester formation at the 2'-OH group. Here we report a cytidine-specific alkyltransferase ribozyme (CSAR) that uses O6-benzylguanines as alkyl group donors. CSAR is the first ribozyme that catalyzes direct alkylation of the exocyclic amino group of a nucleobase and generates N4-alkylated cytidine in a defined sequence context of a short RNA hairpin loop. In combination with tuning the electronic parameters of the transferred benzyl group, CSAR enables highly efficient cytidine alkylation for the installation of bioorthogonal functional groups.

Histopathological analysis in type 1 diabetes presents challenges in achieving precise characterisation with cellular quantification from whole-slide images (WSIs). To ensure a comprehensive understanding of changes in endocrine cells, this study leveraged a pre-trained deep learning-assisted analysis workflow to enhance the understanding of histopathological features of type 1 diabetes development across pancreases from control, autoantibody-positive and type 1 diabetes organ donors. Three pancreatic sections (head, body and tail regions), stained for insulin (INS), glucagon (GCG) and CD3 by immunohistochemistry, were analysed from 32 autoantibody-negative control donors, 12 single-autoantibody-positive (sAAb+) donors, eight multi-autoantibody-positive (mAAb+) donors, six donors with recent-onset type 1 diabetes (0-1 years disease duration) and 19 donors with longstanding type 1 diabetes. Endocrine cell groups (i.e. clusters [<1000μm2] and islets [≥1000μm2]) were segmented by a pre-trained Segment Anything Model, followed by precise segmentation for INS+ and GCG+ cell regions within these structures using a QuPath pixel classifier. CD3+ cells located within a 20 µm periphery of each endocrine cell group were quantified. Ordinal regression was applied to assess disease stage-associated patterns in quantified predictors. The Kruskal-Wallis test was used to compare across the five donor groups. For pairwise comparisons, Wilcoxon rank-sum tests with Bonferroni correction were conducted. From a total of 231 WSIs from 77 donors, >82,000 islets and >26,000 clusters were analysed. In ordinal regression, fractional INS and GCG areas were the most significant predictors of type 1 diabetes progression. CD3+ immune cell infiltration in islets demonstrated a high association with type 1 diabetes progression. Infiltration in both islets and clusters peaked at disease onset before declining, suggesting that these structures are synchronised targets within the autoimmune process. Insulitic clusters were evident even prior to the onset of type 1 diabetes, underscoring the early involvement of these structures in the autoimmune process. The deep learning-powered approach enabled our study to include clusters of endocrine cells scattered throughout WSIs, providing precise quantitative evidence of cluster-level infiltration. The identification of autoimmune patterns in both islets and clusters, alongside the quantification of beta and alpha cells across donor groups and pancreatic regions, offers a more detailed understanding of type 1 diabetes pathogenesis. Our findings provide robust evidence of cluster-level infiltration even before type 1 diabetes onset, supporting early intervention efforts to preserve beta cells.

Repeat blood donation affects erythrocyte health through physiological adaptations. This study examines how repeat donation affects erythrocyte morphology, oxidative stress and erythropoiesis-regulating microRNAs (miRNAs: miR-142, miR-144, miR-451). A cross-sectional study included 42 male participants: repeat donors (n = 21, ≥3 donations/year) and first-time donors (n = 21). Whole blood miRNA expression was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR), hemogram parameters by autoanalysers and oxidative markers (malondialdehyde [MDA], glutathione [GSH]) spectrophotometrically. A Directed Acyclic Graph was constructed for variable selection, and separate linear regression models with Gaussian error distribution were fitted for each miRNA in repeat and first-time donor groups, including 2-year donation count, age, body mass index, smoking, erythrocyte morphology (haemoglobin, mean corpuscular volume, red cell distribution width) and oxidative stress parameters (erythrocyte GSH, plasma GSH, erythrocyte MDA, plasma MDA) as predictors. Univariate analysis revealed a significant 3.17-fold upregulation of miR-142 in repeat donors (p = 0.040); miR-144 and miR-451 remained stable. Linear regression analysis identified two key findings: (1) eGSH was a significant predictor of miR-142 expression in first-time donors (β = -0.080, p = 0.041), representing a fundamental redox-miRNA relationship independent of donation status; and (2) smoking approached significance as a predictor of miR-144 in repeat donors (β = 2.819, p = 0.053), approaching significance and suggesting a possible cumulative oxidative stress threshold. No predictor reached significance for miR-451 in either group, confirming its homeostatic stability. Repeat blood donation is associated with significant miR-142-3p upregulation. Linear regression analysis reveals a novel eGSH-miR-142 axis as a fundamental erythrocyte physiological mechanism and provides suggestive evidence for a double-hit hypothesis for miR-144 regulation in smoking donors. miR-451 demonstrates donor-independent homeostatic stability with potential as a blood product quality reference marker.

The use of pediatric donors in simultaneous pancreas-kidney transplantation (SPKT) and solitary pancreas transplantation is not universally accepted METHODS: Single center retrospective review of 310 consecutive SPKTs and 50 solitary pancreas transplants performed from 11/1/01 to 1/1/25. All patients received depleting antibody induction with tacrolimus/mycophenolate/prednisone maintenance therapy. Pediatric donors were defined as age <18 years. In the SPKT group, 72 patients (23.2%) received organs from donors <18 years (mean 13.9 years), 215 from donors 18-40 years (mean 26.4 years), and 23 from donors >40 years of age (mean 47.4 years). Rates of early pancreas thrombosis were 5.6%, 6.5%, and 4.3% (p = 0.51), according to increasing donor age category. One-year death-censored pancreas and kidney graft survival rates (GSRs) were 93.0%, 92.0%, and 90.5%; and 98.6%, 99.1%, and 95.5%, respectively (both p = NS). Four-year death-censored pancreas GSRs were 87.9%, 78.7%, and 90.5%, respectively (p = 0.08). There were 11 pediatric donors ≤40kg body weight (smallest 28kg). One-year patient, pancreas, and kidney GSRs were 100% and 4-year patient and pancreas GSRs were 100% (kidney GSR 90%). There were no technical pancreas or kidney graft losses in the ≤40kg donor group, and pancreas graft survival beyond 18 years has occurred. In 11 patients receiving solitary pancreas transplants from pediatric donors, there were no cases of early thrombosis. Despite concerns related to small caliber vessels and donor/recipient size mismatch, pediatric donors are associated with excellent mid-term outcomes in SPKT recipients and may not represent a contraindication to pancreas utilization in solitary pancreas transplantation.

Nonstandard Donors With Acceptable Risk for Infectious Disease in Kidney And Kidney-Pancreas Transplants: A Promising Solution.

An intact vescio-ureteric junction (VUJ) complex is necessary to maintain its normal physiological function. A ureteric jet is produced when urine is vigorously propelled from the VUJ into the urinary bladder. The transplanted ureter lacks a normal VUJ but maintains its intrinsic peristaltic activity. this study was conducted to compare prospectively between the ureteric jet parameters in voluntary kidney donors by Doppler ultrasound of the same with patients who underwent ureteric re-implantation during a kidney transplantation procedure. There were a total of 44 participants in the study. The outcome measurements were taken of the anteriorposterior diameter of the renal pelvis (RP-APD), the resistive index of the renal artery (RA-Ri), and ureteric jet parameters- the jet's maximum velocity, pattern, initial slope, direction, and duration. The patterns were of the following types - triphasic, biphasic, polyphasic, square, continuous, and monophasic. The biphasic and monophasic jet pattern was most common in the donor and recipient groups, respectively. The Doppler waveform observed in transplanted ureters significantly differs from that seen in healthy voluntary kidney donors. This observation lends support to the theory that the native VUJ functions as a sphincter.

High thermal conductivity biphenyl-type polyester with photochromism, thermo-responsive, and shape memory performance.

A sulfur-atom-enhanced strategy for NIR imaging of soluble and insoluble amyloid-β species.

Conformity to stochastic invariance of microstructure influences mechanical competence of trabecular bone.

Pretreatment decrease of the anti-müllerian hormone level does not translate into the proportionally lower efficiency of ovarian stimulation in patients with haematological malignancies.

Photoinduced protein labeling strategies have become essential tools in chemical biology, but most strategies require high-energy wavelengths of light as input to drive reactivity. Recently, we reported a biocompatible method for engaging photoinduced electron transfer to drive protein labeling using biarylpyridinium salts, and here, we report the design of a series of aromatic cation salts that trigger this process using longer wavelengths of light while maintaining a sterically minimal profile. We achieved this through the systematic study of structure-reactivity relationships of various donor-acceptor pyridinium salts possessing extended conjugation, and these studies revealed the need of a constrained trans-stilbene relationship between the probe's donor and acceptor substituents in order to achieve protein labeling. Probes with chromene-based donor groups in particular showed either robust protein labeling, significant fluorescence quantum yields, or state-dependent photophysical properties, in turn enabling the same probes to be used for both photoinduced protein labeling and wash-free, live cell imaging. These qualities were then harnessed for live cell labeling using green light photoactivation with two different aromatic cation probes that show complementary photophysical properties and microenvironment responsiveness. Mass spectrometry-based analysis of labeled proteins revealed that each probe enriched highly distinct (<10% protein enrichment overlap) proteomic subsections from primarily mitochondria and the endoplasmic reticulum. This series of experiments not only demonstrates the ability of this latest generation of probes to engage in photoinduced labeling using lower-energy light in complex proteomes but also reveals new capabilities for photophysical state-dependent reactivity and measurements.

Certain heavy metal(loid)s are established nephrotoxicants; however, the associations between metal(loid) exposure and renal function remain complex and may be confounded in observational studies. This study investigated the relationships between urinary concentrations of total arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) and estimated glomerular filtration rate (eGFR) in two distinct Dutch populations: individuals with kidney disease (the disease group) and healthy kidney donors prior to nephrectomy (the donor group). We applied a Bayesian Kernel Machine Regression (BKMR) model with multiple imputation to assess both individual and combined associations between urinary metal(loid) concentrations and eGFR using cross-sectional data. In the disease group, urinary Cd, Hg, and Pb concentrations showed weak positive associations with eGFR, whereas urinary total As concentrations were weakly negatively associated with eGFR. Further mechanistic studies are warranted to explain these findings. No statistically significant associations were found in the donor group, possibly due to compensatory renal mechanisms. No strong interactions were detected among heavy metal(loid)s in relation to renal function. Model diagnostics confirmed the robustness of the results.

Human flora-associated (HFA) mice are often used to simulate the structure of human intestinal microbiota and to study the causal relationships between diseases and gut microbiota. However, several factors affect the colonization efficiency of human microbiota in germ-free (GF) mice, and the differential effects of gavage and lower gut transplantation on colonization are still unclear. In this study, we explored the reproducibility of the recipient-to-donor gut microbiota community structure and function under different transplantation routes and the differences in microbial colonization between recipients via gavage transplantation (GT_mice group) and lower gut transplantation (LGT_mice group). High-throughput sequencing of the metagenome was performed on the feces of each subject, and the composition of microbiome of each group was analyzed. As expected, the introduction of human fecal microbiota into GF mice via lower gut transplantation had a high transfer efficiency, which was evident from the similar species community structure to that of the donor (Adonis R2=0.713 960 for LGT_mice group‒donor group; Adonis R2=0.774 095 for GT_mice group‒donor group) and a higher bacterial colonization rate. The findings provide unique insights into improving the accuracy of constructing humanized microbiota transplantation models, aiding our understanding of the relationships between the human gut microbiota and disease.

Corneal tissue shortage is an ongoing concern for corneal surgeons and eye banks across the United States. Descemet membrane endothelial keratoplasty (DMEK) procedure numbers surpassed Descemet stripping automated endothelial keratoplasty in 2023, leading to an increased demand that has been met with limited DMEK tissue availability. In response to the growing demand, our goal is to compare and characterize feasibility of DMEK tissue from donors younger than 50 and donors 50 and older, including DMEK tissue processing times, preprocessing endothelial cell counts, and processing success rate. Retrospective review of donor corneas used for DMEK tissue processing from 2018 to 2024 at a single eye bank with a post hoc analysis. A total of 8915 cornea samples were used for transplantation during study period. Preprocessing endothelial cell counts were not significantly different between donor group age 50 or older or donor group younger than 50. Postprocessing endothelial cell counts were higher for donor group under 50. There was no statistically significant difference in processing times between donors 50 or older or younger than 50. Tissue peel difficulty was significantly reduced in donors younger than 50 compared to donors 50 or older. Preprocessing endothelial cell counts were similar between both age groups with higher postprocessing endothelial cell counts in donors younger than 50. Tissue processing time and tissue processing failure rate were also similar between the 2 age groups while tissue from donors less than 50 was easier to peel. This highlights that younger donors are a viable pool for DMEK tissue, which could help address the ongoing tissue shortage.

Excess adiposity has been associated with Hodgkin lymphoma (HL) development, but its implications remain unclear. Bone marrow (BM), a frequent extranodal involvement site, contains both red and fatty yellow marrow. We investigated whether obesity influences HL outcomes and characterized the BM and cytokine profiles. In this retrospective study, HL patients were analyzed to assess the association between obesity with relapse and mortality. Yellow and red marrow composition were evaluated using CT imaging and correlated with HL outcomes. A nested study analyzed cytokines in the interstitial marrow fluid (IMF) and in circulation of HL patients, in comparison to a control group of healthy blood donors. Further, invitro functional analyses were performed. Overweight/obesity in HL patients was associated with lower rates of BM involvement, disease relapse, and mortality. Moreover, dense yellow marrow was related to increased risk of death. HL subjects had elevated levels of adiponectin in IMF compared to marrow donors, whereas higher insulin, interleukin 8, and osteoprotegerin levels in IMF were associated with shorter time to relapse. At the molecular level in BM, HL patients had overexpression of LEPR and IGFBP3 in adipocytes, while stromal cells overexpressed IGF-axis receptors. Inin vitro studies, human recombinant IGF-1 significantly induced the L428 HL cell line proliferation, which when combined with IGFBP-3 modified apoptosis. The current findings suggest that obesity is associated with a lower incidence of BM involvement and mortality in patients with HL. The obesity together with HL mechanistically influences systemic and local BM cytokine production, thereby impacting HL fate.

Background The availability of donated blood in Uganda rests on the goodwill of voluntary donors. Previous studies have shown that intention to donate blood predicts the practice of blood donation. To design interventions aimed at improving the availability of donated blood, there is a need to understand intention to donate blood. This study aimed to apply the theory of planned behavior (TPB) to assess the factors associated with the intention to donate blood among secondary school students, the major blood donor group in Uganda. Methods We analyzed secondary data from the blood donation awareness project baseline survey. The blood donation awareness project baseline survey was conducted in four purposively selected secondary schools in East Central Uganda. All the students eligible for the study were invited to participate in the baseline survey. A self-administered questionnaire was used to collect data on the socio-demographic characteristics as well as the TPB constructs. Data were analyzed in STATA version 14. Correlations and structural equation modelling were used to examine the associations among the TPB constructs. A p-value of < 0.05 was considered significant. Results The mean score for intention to donate blood was 14.7 out of a total score of 20. The three TPB constructs explained 34.7% variance in the students' intention to donate blood. Perceived behavioral control had the strongest association with the students' intention to donate blood (β = 0.366, p-value < 0.001). Subjective norms were also significantly associated with the students' intention to donate blood (β = 0.080, p-value = 0.003). The students' attitude towards blood donation and moral responsibility were not associated with their intention to donate blood. Conclusion Our findings showed a moderate level of intention to donate blood among the students. Perceived behavioral control and subjective norms were associated with the students' intention to donate blood.

The evolutionary origin of copper-binding proteins remains a central question in prebiotic chemistry. Modern copper proteins predominantly coordinate copper through histidine and cysteine residues, suggesting that these amino acids were selectively favored during early protein evolution. Here, we propose that ultraviolet (UV) radiation acted as a key selective factor in shaping primordial copper-peptides. Spectroscopic analyses suggest that His2 interacts with Cu(II) through contributions from both its N- and C-terminal donor groups, generating a comparatively stronger binding environment and supporting its plausibility as a primitive Cu-binding motif. Yet His2 is intrinsically vulnerable to UV-induced degradation, highlighting the need for stabilizing partners. In contrast, Tyr2 exhibits remarkable photostability and preferentially binds Cu(II) through its N-terminal, consistent with a second-shell protective role analogous to those observed in modern Cu-binding proteins. Together, these findings suggest that Earth's UV-rich environment favored cooperative copper-binding dipeptides, where His₂ provided catalytic functionality while Tyr2 contributed photostability, establishing a plausible pathway from simple Cu-peptide complexes to functional metalloenzymes.

Open shell luminescent organic molecules have been gaining attention in recent years for their ability to access different excited state manifolds compared to their closed shell congeners. However, there has been little work to expand the design of these systems beyond direct conjugation strategies. Herein, we report the synthesis, and optical and magnetic characterization of two new triarylmethyl radical compounds that interact via a remote homoconjugation with a donor group through a [2.2.2] bridge. The properties of these bridged radicals are compared to those of a non-bridged species. This study ultimately expands the design strategies for synthesizing emissive radical species.