Abstract Purpose Circumcision is the most common surgical procedures performed in males. Medical circumcision is recommended for diseases such as phimosis, paraphimosis, balanoposthitis and common ...urinary tract infections, although there is no exact indication. Conversely, Jewish and Muslim individuals commonly undergo circumcision regardless of medical necessity. Circumcision devices are designed to shorten surgery time, achieve an aesthetic appearance and ensure safe surgery. The aim of this study is to evaluate the effectiveness of the NeoAlis clamp, a disposable circumcision device, by comparing it with the sleeve technique in children. Materials and methods Between 2017 and 2023, retrospective evaluation of 2626 patients who underwent circumcision using either the NeoAlis clamp (group 1) or the sleeve technique (group 2) was conducted. Operation time, results, cost, complications were compared between the two groups. Results The study encompassed 2626 patients who fulfilled the inclusion criteria. Group 1 comprised 2403 patients, whereas Group 2 consisted of 223 patients. The overall complication rate, as denoted by n = 47, was 1.7%. Group 1 operation time was shorter than group 2. Bleeding, the most feared complication in the early period, was higher in the second group. No statistically significant difference was observed between the two groups regarding cost comparison. Conclusion The primary concern during circumcision is to avoid complications related to general anesthesia in newborns and infants. The use of disposable ring devices has been facilitated by the shorter operation time and the absence of the need for sutures when performing circumcision under local anesthesia. However, knowledge of advanced surgical circumcision techniques is necessary in cases of bleeding and inappropriate ring placement.
Abstract In all eukaryotes, acetylation of histone lysine residues correlates with transcription activation. Whether histone acetylation is a cause or consequence of transcription is debated. One ...model suggests that transcription promotes the recruitment and/or activation of acetyltransferases, and histone acetylation occurs as a consequence of ongoing transcription. However, the extent to which transcription shapes the global protein acetylation landscapes is not known. Here, we show that global protein acetylation remains virtually unaltered after acute transcription inhibition. Transcription inhibition ablates the co-transcriptionally occurring ubiquitylation of H2BK120 but does not reduce histone acetylation. The combined inhibition of transcription and CBP/p300 further demonstrates that acetyltransferases remain active and continue to acetylate histones independently of transcription. Together, these results show that histone acetylation is not a mere consequence of transcription; acetyltransferase recruitment and activation are uncoupled from the act of transcription, and histone and non-histone protein acetylation are sustained in the absence of ongoing transcription.
The dynamic architecture of chromatin fibers, a key determinant of genome regulation, is poorly understood. Here, we employ multimodal single-molecule Förster resonance energy transfer studies to ...reveal structural states and their interconversion kinetics in chromatin fibers. We show that nucleosomes engage in short-lived (micro- to milliseconds) stacking interactions with one of their neighbors. This results in discrete tetranucleosome units with distinct interaction registers that interconvert within hundreds of milliseconds. Additionally, we find that dynamic chromatin architecture is modulated by the multivalent architectural protein heterochromatin protein 1α (HP1α), which engages methylated histone tails and thereby transiently stabilizes stacked nucleosomes. This compacted state nevertheless remains dynamic, exhibiting fluctuations on the timescale of HP1α residence times. Overall, this study reveals that exposure of internal DNA sites and nucleosome surfaces in chromatin fibers is governed by an intrinsic dynamic hierarchy from micro- to milliseconds, allowing the gene regulation machinery to access compact chromatin.
Locking plates are commonly used for the fixation of comminuted, periprosthetic and osteoporotic bone fractures. These plates are secured to the bone with screws, creating a stable connection with ...fixed angle between the plate and the screws. In this biomechanical in vitro study, our aim is to evaluate and compare the novel locking plate-locking spongious screw model with FDA approved classical locking plate.
Sawbone PCF-15 osteoporotic bone model was utilized to simulate osteoporotic bone conditions. Two screws were used to attach both the classical locking plate and the novel locking plate-locking spongious screw model to these bone models. The attachment strength of the screws to the bone blocks was measured by pull-out tests.
Novel locking plate-locking spongious screw model exhibited an 84.38% stronger attachment to the osteoporotic bone model compared to the current locking plate model.
In conclusion, one of the important problems in the locking plates which is the high Pull-out risk of the locking spongious screws can been resolved with our proposed new model and has a chance of having a better purchase especially in osteoporotic bones.
Introduction: Testicular cancer is a significant malignancy affecting males, and understanding the underlying biochemical changes associated with the disease is essential for improved management and ...treatment strategies. Prolidase enzyme, has been implicated in various disease processes. The assessment of serum prolidase activity and its relationship with testicular cancer can provide valuable insights into the pathophysiology of the disease. The objective of this study was to investigate serum prolidase activity, oxidative stress markers, and antioxidant enzyme levels in patients with testicular cancer and evaluate their potential associations, aiming to enhance our understanding of the biochemical alterations and potential implications for testicular cancer management. Methods: A total of 33 male patients diagnosed with testicular cancer were included, along with 35 age-matched male volunteers as the control group. Serum samples were collected and stored at −20°C until analysis. The measurement of superoxide dismutase (SOD), glutathione peroxidase (GSHPx), glutathione-S-transferase (GST), malondialdehyde (MDA), glutathione (GSH), and prolidase levels was performed. Results: The findings demonstrated significantly elevated serum prolidase activity and malondialdehyde (MDA) levels in testicular cancer patients compared to the control group (all, p < 0.05). Conversely, superoxide dismutase (SOD), glutathione peroxidase (GSHPx), and glutathione-S-transferase (GST) levels were significantly lower in testicular cancer patients ( p < 0.05). Conclusion: In this study, serum prolidase activity and biochemical markers associated with oxidative stress were investigated in testicular cancer patients. Oxidative stress markers and serum prolidase activity were found to be elevated in testicular cancer. Long-term prospective studies are needed to determine the effectiveness of antioxidant use in cancer treatment.
The SUV39 class of methyltransferase enzymes deposits histone H3 lysine 9 di- and trimethylation (H3K9me2/3), the hallmark of constitutive heterochromatin. How these enzymes are regulated to mark ...specific genomic regions as heterochromatic is poorly understood. Clr4 is the sole H3K9me2/3 methyltransferase in the fission yeast
Schizosaccharomyces pombe,
and recent evidence suggests that ubiquitination of lysine 14 on histone H3 (H3K14ub) plays a key role in H3K9 methylation. However, the molecular mechanism of this regulation and its role in heterochromatin formation remain to be determined. Our structure-function approach shows that the H3K14ub substrate binds specifically and tightly to the catalytic domain of Clr4, and thereby stimulates the enzyme by over 250-fold. Mutations that disrupt this mechanism lead to a loss of H3K9me2/3 and abolish heterochromatin silencing similar to
clr4
deletion. Comparison with mammalian SET domain proteins suggests that the Clr4 SET domain harbors a conserved sensor for H3K14ub, which mediates licensing of heterochromatin formation.
Highly charged intrinsically disordered proteins are essential regulators of chromatin structure and transcriptional activity. Here we identify a surprising mechanism of molecular competition that ...relies on the pronounced dynamical disorder present in these polyelectrolytes and their complexes. The highly positively charged human linker histone H1.0 (H1) binds to nucleosomes with ultrahigh affinity, implying residence times incompatible with efficient biological regulation. However, we show that the disordered regions of H1 retain their large-amplitude dynamics when bound to the nucleosome, which enables the highly negatively charged and disordered histone chaperone prothymosin α to efficiently invade the H1-nucleosome complex and displace H1 via a competitive substitution mechanism, vastly accelerating H1 dissociation. By integrating experiments and simulations, we establish a molecular model that rationalizes the remarkable kinetics of this process structurally and dynamically. Given the abundance of polyelectrolyte sequences in the nuclear proteome, this mechanism is likely to be widespread in cellular regulation.
Post-translational modifications (PTMs) of histones are an essential feature in the dynamic regulation of chromatin. One of these modifications, ubiquitylation, has been speculated to directly ...influence the stability of the nucleosome, which represents the basic building block of chromatin. Here we report a strategy for the semisynthesis of site-specifically ubiquitylated histone H2A (uH2A). This branched protein was generated through a three-piece expressed protein ligation approach including a traceless ligation at valine. uH2A could be efficiently incorporated into nucleosomes, thereby opening the way to detailed biochemical and biophysical studies on the function of this PTM. Accordingly, we used uH2A, as well as a previously generated ubiquitylated H2B, in chaperone-coupled nucleosome stability assays to demonstrate that the direct effect of ubiquitylated histones on nucleosomal stability is in fact modest.
The cellular response to DNA damage results in a signaling cascade that primes chromatin for repair. Combinatorial post-translational modifications (PTMs) play an important role in this process by ...altering the physical properties of chromatin and recruiting downstream factors. One key signal integrator is the histone variant H2A.X, which is phosphorylated at a C-terminal serine (S139ph), and ubiquitylated within its N-terminal tail at lysines 13 and 15 (K13/15ub). How these PTMs directly impact chromatin structure and thereby facilitate DNA repair is not well understood. Detailed studies require synthetic access to such N- and C-terminally modified proteins. This is complicated by the requirement for protecting groups allowing multi-fragment assembly. Here, we report a semi-synthetic route to generate simultaneously N- and C-terminally modified proteins using genetically encoded orthogonal masking groups. Applied to H2A.X, expression of a central protein fragment, containing a protected N-terminal cysteine and a C-terminal thioester masked as a split intein, enables sequential C- and N-terminal protein modification and results in the convergent production of H2A.X carrying K15ub and S139ph. Using single-molecule FRET between defined nucleosomes in synthetic chromatin fibers, we then show that K15 ubiquitylation (but not S139ph) impairs nucleosome stacking in tetranucleosome units, opening chromatin during DNA repair.
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