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Tissue‐mimicking reference phantoms are indispensable for the development and optimization of magnetic resonance (MR) measurement sequences. Phantoms have greatest utility when they mimic the MR signals arising from tissue physiology; however, many of the properties underlying these signals, including tissue relaxation characteristics, can vary as a function of magnetic field strength. There has been renewed interest in magnetic resonance imaging (MRI) at field strengths less than 1 T, and phantoms developed for higher field strengths may not be physiologically relevant at these lower fields. This work focuses on developing materials with specific relaxation properties for lower magnetic field strengths. Specifically, we developed recipes that can be used to create synthetic samples for target nuclear magnetic resonance relaxation values for fields between 0.0065 and 0.55 T. T1$$ {T}_1 $$ and T2$$ {T}_2 $$ mixing models for agarose‐based gels doped with a paramagnetic salt (one of CuSO4, GdCl3, MnCl2, or NiCl2) were created using relaxation measurements of synthetic gel samples at 0.0065, 0.064, and 0.55 T. Measurements were evaluated for variability with respect to measurement repeatability and changing synthesis protocol or laboratory temperature. The mixing models were used to identify formulations of agarose and salt composition to approximately mimic the relaxation times of five neurological tissues (blood, cerebrospinal fluid, fat, gray matter, and white matter) at 0.0065, 0.0475, 0.05, 0.064, and 0.55 T. These mimic sample formulations were measured at each field strength. Of these samples, the GdCl3 and NiCl2 measurements were closest to the target tissue relaxation times. The GdCl3 or NiCl2 mixing model recipes are recommended for creating target relaxation samples below 0.55 T. This work can help development of MRI methods and applications for low‐field systems and applications. [ABSTRACT FROM AUTHOR]

Purpose: To compare T1 and T2 measurements across commercial and prototype 0.55T MRI systems in both phantom and healthy participants using the same vendor‐neutral pulse sequences, reconstruction, and analysis methods. Methods: Standard spin echo measurements and abbreviated protocol measurements of T1, B1, and T2 were made on two prototype 0.55 T systems and two commercial 0.55T systems using an ISMRM/NIST system phantom. Additionally, five healthy participants were imaged at each system using the abbreviated protocol for T1, B1, and T2 measurement. The phantom measurements were compared to NMR‐based reference measurements to determine accuracy, and both phantom and in vivo measurements were compared to assess reproducibility and differences between the prototype and commercial systems. Results: Vendor‐neutral sequences were implemented across all four systems, and the code for pulse sequences and reconstruction is freely available. For participants, there was no difference in the mean T1 and T2 relaxation times between the prototype and commercial systems. In the phantom, there were no significant differences between the prototype and commercial systems for T1 and T2 measurements using the abbreviated protocol. Conclusion: Quantitative T1 and T2 measurements at 0.55T in phantom and healthy participants are not statistically different across the prototype and commercial systems. [ABSTRACT FROM AUTHOR]

Background: Bosniak classification version 2019 (v2019) was a major revision to version 2005 (v2005) that defined cystic renal mass subclasses based on wall or septa features. Objective: To determine the proportion of malignancy within cystic renal masses stratified by Bosniak classification v2019 class and feature-based subclass. Evidence Acquisition: MEDLINE and EMBASE databases were searched on July 24, 2023 for studies published in 2019 or later that reported cystic renal masses that underwent renal-mass CT or MRI, were assessed using Bosniak v2019, and had a reference standard (histopathology indicating benignity or malignancy or ≥5-year imaging follow-up indicating benignity). Study authors were contacted to provide subclass-stratified data. Pooled proportions of malignancy stratified by v2019 class and subclass were determined using meta-analysis. Evidence Synthesis: The analysis included 12 studies reporting 966 patients with 975 cystic masses. No class I mass was malignant. Pooled proportions of malignancy by class were: II, 9% (95% CI: 5-17%); IIF, 26% (95% CI: 13-46%); III, 80% (95% CI: 71-87%); IV, 88% (95% CI: 83-91%). Pooled proportions of malignancy by subclass were: IIF with many smooth, thin septa, 10% (95% CI: 2-33%); IIF with minimal wall or septal thickening, 47% (95% CI: 18-77%); IIF with heterogeneous T1-weighted hyperintensity, 26% (95% CI: 8-57%); III with thick smooth wall or septa, 78% (95% CI: 60-90%); III with obtuse protrusion(s) ≤3 mm, 84% (95% CI: 77-90%); IV with acute protrusion(s) of any size, 88% (95% CI: 80-93%); IV with obtuse protrusion(s) ≥4 mm, 86% (95% CI: 77-91%). Proportion of malignancy was 41% for IIF masses with histopathology reference versus 2% for IIF masses with imaging follow-up reference. In four studies performing intraindividual comparisons of v2005 versus v2019, proportion of malignancy was: IIF, 24% versus 42% (p=.13); III, 74% versus 77% (p=.72); IV, 79% versus 84% (p=.22) Conclusion: Bosniak IIF masses had higher malignancy rates when histopathology rather than imaging follow-up was the reference standard, indicating verification bias. All Bosniak III and IV subclasses had high malignancy rates. Clinical Impact: The results improve understanding of imaging-based cystic renal mass classification and may inform development of future renal mass classification systems.

Purpose: The optimal management of patients with de novo clinical stage IIA/B (CSIIA/B) or relapsed CSIIA/B (Rel-CSIIA/B) seminoma remains debated due to a lack of randomized evidence. Herein, we sought to evaluate outcomes following radiotherapy and chemotherapy in this setting., Materials and Methods: A prospectively maintained single-institutional database was retrospectively queried for patients diagnosed between 1995-2016 with de novo or Rel-CSIIA/B. Patients with Rel-CSIIA/B were managed similarly to de novo CSIIA/B. All patients were reviewed by the multidisciplinary team. While the preferred management policy was radiotherapy, the treatment decision was individualized at the physician/patient level., Results: There were 153 patients: 67 had de novo CSIIA/B (IIA-32, IIB-35) and 86 patients had Rel-CSIIA/B seminoma (IIA-51, IIB-35). Of the total, 120 patients (78%) received radiotherapy (IIA-78, IIB-42) and 33 (22%) received platinum-based chemotherapy (IIA-5, IIB-28). Median follow-up was 7.1 years (IQR 4.3-9.9). Eleven patients (IIA- 9/78, IIB- 2/42) relapsed following radiotherapy and 1 patient (IIB) relapsed following chemotherapy, corresponding to 5-year relapse rates of 10% (95% CI 6-18%) for radiotherapy and 3% (95% CI 0-23%) for chemotherapy. All 12 patients who relapsed were treated with subsequent chemotherapy., Conclusion: Radiotherapy and chemotherapy result in excellent oncologic outcomes for patients with de novo or Rel-CSIIA/B seminoma. All patients should be informed about both management options. However, radiotherapy with its favourable acute toxicity profile, could be considered the treatment of choice in most patients., (Copyright © 2025. Published by Elsevier Inc.)

During memory formation, the hippocampus is presumed to represent the content of stimuli, but how it does so is unknown. Using computational modelling and human single-neuron recordings, we show that the more precisely hippocampal spiking variability tracks the composite features of each individual stimulus, the better those stimuli are later remembered. We propose that moment-to-moment spiking variability may provide a new window into how the hippocampus constructs memories from the building blocks of our sensory world., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Dystrophy-associated fer-1-like protein (dysferlin) conducts plasma membrane repair. Mutations in the DYSF gene cause a panoply of genetic muscular dystrophies. We targeted a frequent loss-of-function, DYSF exon 44, founder frameshift mutation with mRNA-mediated delivery of SpCas9 in combination with a mutation-specific sgRNA to primary muscle stem cells from two homozygous patients. We observed a consistent >60% exon 44 re-framing, rescuing a full-length and functional dysferlin protein. A new mouse model harboring a humanized Dysf exon 44 with the founder mutation, hEx44mut, recapitulates the patients' phenotype and an identical re-framing outcome in primary muscle stem cells. Finally, gene-edited murine primary muscle stem-cells are able to regenerate muscle and rescue dysferlin when transplanted back into hEx44mut hosts. These findings are the first to show that a CRISPR-mediated therapy can ameliorate dysferlin deficiency. We suggest that gene-edited primary muscle stem cells could exhibit utility, not only in treating dysferlin deficiency syndromes, but also perhaps other forms of muscular dystrophy., Competing Interests: Competing interests: Si.S. is an inventor on a technology for primary human muscle stem cell isolation and manufacturing (IP: (DE10 2014 216872), 2015 PCT (WO 2016/030371), granted in EU and US). Si.S. and H.E. are co-inventors on a pending patent application on gene editing of human muscle stem cells (European Patent Office 21 160 696.7). Si.S. is co-founder of MyoPax GmbH and MyoPax Denmark ApS. The remaining authors declare no competing interests., (© 2024. The Author(s).)

Chronic obstructive pulmonary disease (COPD) remains a major public health problem with relatively high prevalence rates worldwide (5.0-13.0%). COPD is a major cause of morbidity and mortality worldwide and results in an economic and social burden that is both substantial and increasing. The purpose of the study was to explore the alteration of serum iron in patients with COPD. This cross-sectional study was carried out in the Department of Biochemistry, Mymensingh Medical College, Bangladesh from January 2021 to December 2021. Data was collected from Medicine Department of Mymensingh Medical College Hospital, Bangladesh. A total number of 120 subjects participated in this study. Out of them, 60 apparently normal healthy individuals were selected as Group I and another 60 diagnosed COPD patients were selected as Group II. Serum iron was measured by CAB method. Statistical package for social science (SPSS), version 21.0 was used for results calculation and analysis. Data were expressed in mean ±SD and statistical significance was done by Student's unpaired 't' test. The mean results of serum iron were 97.60±5.50 μg/dl in Group I and 49.80±5.92 μg/dl in Group II (p<0.001). This study found the relation between COPD and alteration of serum iron was statistically significant. So, by this study we recommended that routine evaluation of serum iron is important for prevention of exacerbations, reduction of morbidity and mortality in patients with COPD.

Type 2 diabetes, formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance and relative lack of insulin. This cross sectional study was carried out in the Department of Biochemistry, Mymensingh Medical College and in collaboration with the Department of Endocrinology, Mymensingh Medical College Hospital, Mymensingh from July 2021 to June 2022. A total of 100 subjects were included in this study. Among them 50 were diagnosed type 2 diabetes mellitus patients denoted as case group and 50 were apparently healthy individuals denoted as control group selected on the basis of inclusion and exclusion criteria. Serum vitamin D was estimated by chemiluminescence immunoassay from the subjects. Data were then processed and analyzed. Statistical analysis was done by using SPSS (Statistical Package for Social Science) version 26 windows package. The study revealed that, mean±SD values of vitamin-D were 25.50±3.63 ng/ml and 27.72±5.25 ng/ml in Group I and Group II respectively. Student's unpaired 't' test was done to measure the level of significance. Serum vitamin-D was significantly lower in Group I than that of Group II. This result has an association with type 2 diabetes mellitus progression and also may has important role in the etiology of type 2 diabetes mellitus and its complications.

Chronic kidney disease (CKD) is one of the largest public health issues and the major cause of death worldwide. Due to an increase in the incidence of systemic diseases like diabetes and hypertension, which are the two main causes of CKD and kidney damage, the prevalence of CKD is rising globally. Chronic Kidney Disease results in mineral disorders as well as profound lipid disorders due to improper balancing of the mineral & hormone levels in the body. This cross-sectional study was completed in the Department of Biochemistry, Mymensingh Medical College, in collaboration with the Department of Nephrology, Mymensingh Medical College Hospital, during the period of July 2022 to June 2023. The subjects were selected based on inclusion and exclusion criteria by purposive non-random sampling. Total 120 subjects were included in this study. Out of them, 60 were selected chronic kidney disease patient (Group II) and another 60 apparently normal healthy persons were selected as control (Group I). In this study, serum magnesium levels were measured for analytical study. All the values were demonstrated as mean±SD and values of serum magnesium were in Group I (1.99±0.50 mg/dl) and in Group II (2.24±0.19 mg/dl). Statistical analysis was performed using by statistical package for social science (SPSS) version 26.0. The statistical significance of the difference between the case and control was evaluated using Student's unpaired 't'-test (p<0.001). After careful evaluation, this study was found that mean serum magnesium levels was significantly increased in CKD patients.