bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long term muscle involvement after neonatal pain
Authors: Alves Júlia Aparecida , Simões Ana Leda B , Dias Fernando José , Carmo Elisabete C , Machado Nathalia B , Sanada Luciana S , Fazan Valeria Paula Sassoli 
Published: November 2023

Nociceptive stimuli applied soon after birth play an important role in the development of pain in adult life. Previous studies in our laboratory have shown that pain in the neonatal period can cause a number of changes both in the central nervous system and the musculoskeletal [1], but experimental substrates for these changes still need investigation. We designed an experimental study to explore whether pain in the neonatal period can cause long term changes in the locomotor system. The pain groups (male and female Wistar rats, N = 10 per group) were stimulated with a needle on the right hind paw, twice a day, since birth, for 15 consecutive days. The control groups (male and female Wistar rats, N = 10 per group) were stimulated with a cotton swab. Final experiments were performed 180 days after birth. In order to evaluate the motor function of the hind paws, grip strength tests were conducted. Maximum and average (mean of three consecutive measures) grip strength were studied. Afterwards, rats were anesthetized and the medial gastrocnemius (MG) muscles were obtained by surgical biopsy. The muscle fragments were frozen and stained with the techniques for nictotinamide adenine dinucleotide (NADH) and mitochondrial succinate dehydrogenase (SDH). For muscle morphometry, the number of fibers was counted and their area and diameter were measured. Specific statistic tests were applied and differences were considered significant when p<0.05. The grip strength was higher in males compared to females in both, control and pain groups, but smaller on pain groups, in both genders, compared to controls. Preliminary morphometric results showed that the female pain group had a higher average area of the MG fibers than the control group, while no differences between pain and control groups were found on males. The comparison between genders showed that male controls have larger average number of fibers compared to the females. On the pain groups, females showed larger fiber area compared to males. Our results are suggestive that pain in the neonatal period caused a reduced grip ability that was maintained in the long term after the painful stimulus was ceased, with a slightly better performance on older females. Neonatal pain was also responsible for increasing the average size of muscular fibers in the MG in females, with no apparent effect in males. Increasing the number of animals for the histological studies will help the identification of the type of muscle fibers that are being related to the grip ability alterations observed in this model of pain.Support or Funding InformationFAPESP, CNPq, CAPES and FAEPA
Cadaveric study of the anatomical and histological relationships between the Achilles and plantaris tendons
Authors: Goral Joanna , Inouye Sandra E , Belford Zachary , Leland Eric , Ferrel Benjamin , Cheung Andrew , Meyer Alice , Fanter Nathan 
Published: November 2023

RationaleThe purpose of this study was to investigate whether the proximity in anatomical locations of the Achilles (AT) and plantaris (PT) tendons promotes histopathological changes common to both tendons and their shared paratenon. The Achilles and plantaris tendons (ATs and PTs, respectively) share close anatomical locations in the foreleg, which has led to a proposed association between pathological findings in these tendons. Previous studies have identified such an association in specimens with known tendinopathy. This study aimed to determine whether similar correlation could be found in a group of cadavers without any record of tendon pathology.Materials and methodsThe subjects in this study were 20 donor cadavers (11 females and nine males) fixated in formalin, provided by the Department of Anatomy at Midwestern University. The mean age was 81 (±12). Twenty left, and 19 right legs were dissected. The ATs and PTs were assessed based on their gross anatomical characteristics, then samples of the tendons were harvested from two sites, one where the ATs and PTs ran closely together and a second where the PT was unassociated with the AT. The collected specimens were fixed, processed for paraffin embedding, sectioned, and stained with hematoxylin and eosin for histological analysis. Tissues were examined for the presence of inflammatory cells and for the evidence of stress‐induced conversion of the tendons’ dense connective tissue into fibrocartilage.ResultsIn four specimens (10.2%) the ATs and PTs ran separately, in eight (20.5%) specimens they were fused, and in three specimens the plantaris muscle was absent (7.7%). In the rest of the specimens the ATs and PTs were closely associated, but not fused. Histologically, no distinct evidence of inflammation was found at either the related or unrelated AT and PT sites. A presence of fibrocartilage with chondrocytes within the AT was noted in six (15.4%) specimens.ConclusionThe results of this study did not demonstrate any significant histopathologic changes in the areas of close contact between the ATs and PTs. The presence of fibrocartilage in the Achilles but not in the plantaris tendons suggests that the AT may be more affected by compression‐induced stress than the PT. These findings suggest that within the control group, close contact between AT and PT does not result in interrelated histopathologic changes. However, it is possible that histopathology may be observed in patients with mid‐portion Achilles tendinopathy.Support or Funding InformationZachary Belford and Benjamin Ferrel were supported by the Midwestern University Research Fellowship Program. Eric Leland and Andrew Cheung were supported by the Midwestern University work‐study program.
Computer‐Assisted Anatomical Dissection (CAAD) of the Renal Plexus to Refine Renal Denervation in the Treatment of Refractory Hypertension
Authors: Bessede Thomas , Lebacle Cedric , Timoh Krystel Nyangoh , Martinovic Jelena , Diallo Djibril , Zaitouna Mazen , Benoit Gerard 
Published: November 2023

ContextRadioFrequency (RF) renal denervation is an emerging treatment of refractory arterial hypertension with various possible approaches: endovascular, endourologic, laparoscopic. Results and adverse events remain controversial. Theoretical safety and efficiency of all of the approaches deserve to be addressed with special insight into the anatomy of the renal plexus and hilar structures. The objective was to describe the location and distances between nerve fibers and renal vasculature.MethodsSagittal serial sections were performed in 4 human fetuses and 10 adult bodies were dissected. In fetuses, sections were stained by Masson's trichrome, HE, and immunostained by PS100 neuronal antibody. The nature of renal plexus fibers was investigated by adrenergic (TH) and somatic (PMP22) labelings. In cadavers, the distances between nerve fibers and arteries were measured at the renal ostium, at mid‐artery, at the hilum of the kidney, and were statistically compared (one‐way repeated measures ANOVA). 3D reconstructions were performed from the digitized serial sections obtained in fetuses.ResultsThe renal plexus can be described as a guying contained in an hourglass shape centered on the renal artery. The isthmus of this hourglass corresponds to the hilum of the kidney and is a mandatory waypoint of afferent and efferent renal plexus. At this level, the nerves are at the closest location of arterial branches (11 mm at the renal ostium, 6.5 mm at mid‐artery and 2 mm at the hilum of the kidney; p<0.001). The sectorial distribution of the nerves around the renal artery is heterogeneous and fibers predominate on the superior aspect. Nerve fibers are autonomic (PMP22−) and adrenergic‐sympathetic (TH+). With an animated 3D reconstruction, it is possible to analyze the relationship between renal plexus, vasculature and urinary tract, and the potential risks of various denervation techniques.ConclusionCAAD in fetuses identified the renal hilum as the theoretical preferential site for renal denervation. To optimize endovascular denervation in future clinical studies, a compromise should be sought between the size of the RF probe and the arteries’ diameter. There is an opening to laparoscopic surgical denervation.Support or Funding InformationNone
The anatomy of the human myometrium: A stereological approach
Authors: Dockery Peter , Sweeney Eva Marie , Denis Crankshaw J , John Morrison J 
Published: November 2023

In this presentation we illustrate the usefulness of the stereological approach in providing quantitative anatomical information of the human myometrium in pregnancy. Altered uterine contractile performance has been associated with maternal obesity and advanced maternal age. The aim of this study was to investigate the microanatomy of the human myometrium in pregnancy, and to evaluate a potential influence of maternal body mass index (BMI) and age.Study DesignBiopsies of human myometrium were obtained from 57 women at cesarean section (n = 26, n = 13, n = 18 normal, overweight and obese BMI, respectively). Samples were obtained using a systematic random protocol and processed for light and electron microscopy. A number of absolute and relative stereological were used to document the microanatomy. All material was obtained with informed consent and appropriate ethics committee approval.ResultsThere was found to be significant differences in smooth muscle mitochondrial volume, length density of blood vessels and volume density of smooth muscle nuclei with age. The only BMI related change was found to be in the volume density of connective tissue.ConclusionThe results of our studies suggest that there may be structural changes in the myometium in older women during pregnancy. These results highlight the usefulness of the stereological approach in trying to untangle the structural sequelae of the altered uterine contractile performance has been associated with maternal obesity and advanced maternal age.Support or Funding InformationStudentship from NUIGalway
Optical Clearing and 3D‐Histology of Murine Testis
Authors: Kaufman Jason A. , Castro Monica J. , Rodriguez‐Sosa Jose Rafael 
Published: November 2023

Optical clearing techniques (e.g., CLARITY, Scale, SeeDB, and 3DISCO) provide unprecedented opportunities to study large tissue samples at histological resolution, eliminating the need for physical sectioning while preserving the three‐dimensional structure of intact biological systems. Although these methods have been used primarily to investigate nervous system tissues, there is significant potential for applying optical clearing to reproductive tissues. In testicular biology, for example, the study of spermatogenesis and the use of spermatogonial stem cells offer high‐impact applications in fertility medicine and reproductive biotechnology. Therefore, the objective of our study is to apply optical clearing and immunofluorescence to testicular tissue in order to reconstruct its three‐dimensional microstructure in intact large samples. We used Triton‐X detergent‐based clearing in combination with Refractive Index Matching Solution to achieve optical transparency of fixed mouse testes. An antibody against smooth muscle actin (SMA) was used to label peritubular myoid cells of seminiferous tubules while an antibody against ubiquitin C‐terminal hydrolase (UCHL1) was used to label Sertoli cells and spermatogonia in the seminiferous epithelium. Specimens were then imaged using confocal fluorescence microscopy. Our results demonstrate that we were able to successfully clear testicular tissue and utilize immunofluorescent probes. Even with a basic confocal microscope and conventional objective lenses, we were able to image through as much as 500 microns of cleared tissue (the mechanical limit of our microscope). Moreover, we successfully visualized the histological compartments of testicular tissue in three‐dimensional reconstructions. The anti‐SMA antibody labeled the peritubular myoid cells in striking detail and exhibited their characteristic polygonal morphology. The antibody against UCHL1 provided clear visualization of mouse Sertoli cells and spermatogonia. When complemented with DAPI nuclear staining, the progressive stages of spermatogenesis could be observed proceeding from the basal compartment to the adluminal compartment of the seminiferous epithelium. In summary, optical clearing combined with immunofluorescence and confocal imaging offers a powerful new method to analyze the cytoarchitecture of testicular tissue at histological resolution while maintaining the large‐scale perspective of the intact system.Support or Funding InformationThis research was generously funded by the Arizona Alzheimer's Consortium and Midwestern University.
Studies of Bilateral Asymmetry of the Upper Limb in Adult Males in Ilorin Metropolis, Nigeria
Authors: Oyewopo Adeoye Oyetunji , Gbadamosi Ismail , Ezra Lambe , Arogundade Tolulope , Jaji‐Sulaimon Rukayat 
Published: November 2023

BACKGROUNDThe region of the upper extremity has long been of interest to researchers especially when it comes to handedness. The upper limb or upper extremity is the region of the body extending from the deltoid region to the hand, including the arm, axilla and shoulder. There are several theories of how handedness develops in individual humans. This study aims to investigate the bilateral asymmetry of the upper limb in adult males in Ilorin metropolis.MATERIALS AND METHODSA total of 40 male subjects with equal number of left and right hander between the ages of 18 and 23 within the Ilorin metropolis were used. Various anthropometric measures which include the length of the whole arm; lengths of upper and lower arm, widest circumferences of upper and lower arm of their upper limbs were estimated with aid of a measuring tape.RESULTSAll the parameters in individuals using right showed an increase in right hand readings compared to the left except in the width of the palm that shows increase in the left hand palm width than the right hand but for the left handed individuals, all the parameters showed a decrease in right hand readings compared to the left.CONCLUSIONStatistical analysis of anthropometric measures from the upper limbs of adult males in Ilorin metropolis has clearly indicated that the bilateral asymmetry of the upper limb is an indication of handedness.Support or Funding InformationNIL
Nerve‐Muscle Perforation Variations in the Upper Limb: A Review with a Description of Three New Variants
Authors: Miller Joseph M.A. , Trelease Robert 
Published: November 2023

Muscle perforation by somatic nerves is well known in the body. In the upper limb, three such muscle perforations are classically described: the coracobrachialis perforated by the musculocutaneous nerve (MCN), the pectoralis minor perforated by the medial pectoral nerve, and the supinator perforated by the deep radial nerve. It is less well recognized that there are other muscle perforation variations in the upper limb. This study reviews known muscle perforation variations of the upper limb by somatic nerves and introduces three new observed variants. Bergman et al. (1988) catalog the following four muscle perforation variations: pectoralis minor perforated by the lateral pectoral nerve, the coracobrachialis perforated by the lateral cord, the short head of the biceps perforated by the MCN, and the brachialis perforated by the MCN. As a result of our own cadaveric studies, we discovered the following variations: 1) a third head of the biceps perforated by the MCN, 2) long head of the biceps perforated by the MCN, and 3) pronator teres perforated by the median nerve. These variations are of intrinsic anatomical interest. Clinically, they expand the possible etiologies of compression/entrapment syndromes encountered in the upper limb.Support or Funding InformationWe wish to thank the UCLA Donated Body Program and our donors who gifted their remains for scientific research.
Crystal Structure of the Cancer Genomic DNA Mutator APOBEC3B Catalytic Domain
Authors: Aihara Hideki , Shi Ke , Carpenter Michael A. , Kurahashi Kayo , Harris Reuben S. 
Published: November 2023

BackgroundAPOBEC3 family DNA cytosine deaminases provide overlapping defenses against pathogen infections as part of innate immunity. APOBEC3B is the only family member that is predominantly nuclear‐localized, and recent studies have demonstrated its major role in cancer mutagenesis.MethodsWe used the E. coli‐based rifampicin resistance mutation assay and in vitro DNA deamination assay to guide the generation of a highly soluble and catalytically active APOBEC3B catalytic domain construct, and used X‐ray crystallography to analyze its structures.ResultsWe have determined the first high‐resolution structures of APOBEC3B catalytic domain in multiple crystal forms. The structures revealed a tightly closed active site conformation, which suggest that the binding of a single‐stranded DNA substrate is regulated by adjacent flexible loops. Replacing one of these loops adjacent to the active site (loop 1) with the corresponding loop from the highly homologous cytoplasmic deaminase APOBEC3A generated a hyperactive enzyme, consistent with tight regulation of APOBEC3B activity. We also determined a nucleotide (dCMP)‐bound crystal structure that suggests a possible mode of APOBEC3B‐DNA interaction and informs a multi‐step model for the binding of single‐stranded DNA.Conclusion and SignificanceA comparison between our APOBEC3B structure and those of other cytoplasmic APOBEC3 members with more open active site conformations suggests that the active site accessibility of APOBEC3B may be regulated in a manner that maximizes innate antiviral activity and minimizes damages to genomic DNA. The novel nucleotide‐binding site on the surface of the APOBEC3B catalytic domain is accessible even when the active site is in the closed conformation, and thus it could serve as an initial contact point for a single‐stranded DNA substrate. Given its role in cancer mutagenesis and being a non‐essential enzyme, APOBEC3B is an attractive target for anti‐cancer drug development. Our high‐resolution structures provide a framework for further mechanistic studies and development of APOBEC3B inhibitors to suppress cancer evolution to minimize drug resistance and metastasis.
Investigation of Structure‐Activity Relationships for Small‐Molecule Inhibitors of Human DNA Polymerase Eta
Authors: Zafar Maroof K , Maddukuri Leena , Eddy Sarah , Ketkar Amit , Penthala Narsima R , Crooks Peter A , Eoff Robert L 
Published: November 2023

Efficient DNA replication by high‐fidelity polymerases (pols) can be perturbed by both endogenous and exogenous sources of DNA damage, resulting in accumulation of replication intermediates that activate DNA damage response pathways. DNA damage and replication stress are hallmarks of cancer and cells have intrinsic mechanisms that rely on replication stress response pols to assist in replication fork progression following DNA damage. Many chemo‐ and radio‐therapies rely on targeting DNA, thereby, blocking DNA replication to limit tumor growth. These genotoxic drugs can be rendered ineffective through Translesion DNA synthesis (TLS), involving Y‐family pols, namely human polymerases eta (η), kappa (κ), iota (ι) and Rev1. Most importantly, both in vitro and in vivo studies have highlighted the role of hpol η in bypassing lesions caused by doxorubicin and platinum based drugs. Therefore, targeted inhibition of these specialized pols will improve the ability to destroy cancer cells that rely on these enzymes to survive treatment with genotoxic anti‐cancer drugs. The main objective of our study was to identify small‐molecule inhibitors of hpol η and determine if these molecules show synergy with genotoxic anti‐cancer drugs in an effort to ameliorate existing cancer therapeutics to improve patient outcomes. Catalysis by hpol η was measured in the presence of eighty‐eight small molecules at a single dose of 20 μM from a novel library of more than 100 indole thio‐barbituric acids (ITBA) and indole barbituric acid (IBA) derivatives. From this initial study, we identified several potent inhibitors of hpol η activity. Michaelis‐Menten kinetic analysis and in‐silico docking approaches were employed to determine the mechanism of action for the most potent inhibitors. One of these compounds, PNR‐7‐02, an ITBA derivative with both N‐napthoyl moiety and 5‐chloro substituent on the indole ring inhibits hpol η activity with an IC50 value near 8 μM. In silico docking and Michaelis‐Menten kinetics revealed that PNR‐7‐02 likely inhibits hpol η activity through a partial competitive/allosteric mechanism of action. PNR‐7‐02 inhibited hRev1 and hpol lambda (λ) with low micromolar IC50 values. Another ITBA derivative with a 4‐(2‐ethoxyethyl) morpholine substitution at position 5 on the indole ring (PNR‐9‐59) inhibited hpol η with an IC50 of 13 μM. PNR‐9‐59 showed improved drug‐likeness as well as improved specificity for hpol η against A‐, B‐ and X‐family pols and also within Y‐family pols. In summary, our work has improved the potency and drug‐likeness of small‐molecule inhibitors of hpol η, and it stands as the first detailed analysis of structure‐activity relationships for inhibitors of a TLS pol involved in resistance to chemotherapeutics.Support or Funding InformationThis work was supported by NIH grants GM 084460 and CA 183895 (to R.L.E.).
Biochemical and Biological Investigation of Human Polymerase Kappa Activity on G‐Quadruplex DNA
Authors: Eddy Sarah , Maddukuri Leena , Tillman Magdalena , Smith Rachel , Ketkar Amit , Zafar Maroof K , Eoff Robert L 
Published: November 2023

Faithful replication of genomic information is crucial for maintenance of cellular function and integrity. DNA can adopt non‐B‐form structures in vivo, such as G‐quadruplex DNA (G4 DNA). G‐quadruplexes represent highly stable guanine‐rich secondary structures that can hinder DNA replication, impeding B‐family polymerases (pols), which are the enzymes responsible for faithfully copying information contained within DNA sequences. The accurate replication of G4 DNA is important, as these structures regulate transcription of oncogenes and telomere dynamics. Y‐family translesion pols have been implicated in successful G4 DNA replication; thus, we hypothesized that these enzymes may facilitate efficient bypass of G4 DNA structures. The primary goal of the current project is to investigate the role of human Y‐family pol kappa (hpol kappa) in replication of G‐quadruplex sequences with in vitro enzymatic assays and experiments in cell culture. Using fluorescence anisotropy, we find that hpol kappa binds G4 DNA with a 5.6‐fold preference over control, non‐G4 DNA. Results from pol extension assays are consistent with the notion that G‐quadruplexes represent a barrier to DNA replication by pols, and kinetic analysis reveals that activity of hpol kappa is diminished to 12% on highly stable G4 DNA substrates as compared to control, non‐G4 substrates up to ten nucleotides away from a G4 structure. These results are in contrast to a previous study from our group that showed the activity of another Y‐family pol member, hpol eta, is essentially unperturbed ten nucleotides from G4 DNA and can maintain >20% activity even when copying a quadruplex‐associated guanine. Nevertheless, experiments in HeLa cell culture have revealed that stabilization of G4 DNA structures with pyridostatin (PDS) resulted in a ~40% decrease in cell viability for cells depleted of hpol kappa by siRNA compared to scrambled siRNA treatment (P = 0.0455). In summary, our in vitro kinetic analysis does not support a model in which hpol kappa promotes direct bypass of G4 DNA. Instead, the sensitivity of hpol kappa‐deficient cells to PDS may be related to the role of hpol kappa in activation of the replication stress response through ATR‐mediated phosphorylation of Checkpoint kinase 1 (Chk1).Support or Funding InformationThis work was supported by NIH grants GM 084460 and CA 183895 (to R.L.E.).