Repair Site Research Articles

Biomechanical Comparison Between Double-Row Repair and Soft Tissue Tenodesis for Treatment of Proximal Rectus Femoris Avulsions.

Some patients with proximal rectus femoris (PRF) avulsions require surgical treatment after failed nonoperative treatment. There is no consensus on the superiority of suture anchor repair with the suture-bridge repair (SBR) technique versus tenodesis repair (TR) for PRF avulsions. To compare the failure load and elongation at failure between SBR and TR and to compare the stiffness of these 2 repair techniques versus the native state. Controlled laboratory study. Seven pairs of human cadaveric hemipelvises were dissected to the PRF and sartorius origins. Each specimen underwent preconditioning followed by a distraction test to determine the stiffness of the native specimen. One specimen of each pair received one of the repair methods (SBR or TR), while the other specimen in the pair received the other repair technique. After repair, each specimen underwent preconditioning followed by a pull to failure. The failure load, elongation at failure, stiffness, mode of failure, and stiffness as a percentage of the native state were determined for each repair. The SBR group exhibited a stronger failure load (223 ± 51 N vs 153 ± 32 N for the TR group; P = .0116) and significantly higher stiffness as a percentage from the native state (70.4% ± 19% vs 33.8% ± 15.5% for the TR group; P = .0085). While the stiffness of the repair state in the SBR group (41.5 ± 9.4 N/mm) was not significantly different from that of the native state (66.2 ± 36 N/mm), the stiffness of the repair state in the TR group (20.3 ± 7.5 N/mm) was significantly lower compared with that of the native state (65.4 ± 22.1 N/mm; P < .001) and repair state in the SBR group (41.5 ± 9.4 N/mm; P = .02). The SBR group primarily failed at the repair site (71%), and the TR group primarily failed at the suture-sartorius interface (43%) and at the muscle (29%). SBR and TR specimens were significantly weaker than the native tendon. The stiffness of the SBR was equivalent to that of the native tendon, while TR was significantly less stiff than the native tendon. The SBR was superior to TR in terms of failure load, stiffness, and percentage stiffness from the native state. SBR may be a better surgical option than TR to optimize failure load and stiffness for PRF avulsions.

PARP1-DNA co-condensation drives DNA repair site assembly to prevent disjunction of broken DNA ends

DNA double-strand breaks (DSBs) are repaired at DSB sites. How DSB sites assemble and how broken DNA is prevented from separating is not understood. Here we uncover that the synapsis of broken DNA is mediated by the DSB sensor protein poly(ADP-ribose) (PAR) polymerase 1 (PARP1). Using bottom-up biochemistry, we reconstitute functional DSB sites and show that DSB sites form through co-condensation of PARP1 multimers with DNA. The co-condensates exert mechanical forces to keep DNA ends together and become enzymatically active for PAR synthesis. PARylation promotes release of PARP1 from DNA ends and the recruitment of effectors, such as Fused in Sarcoma, which stabilizes broken DNA ends against separation, revealing a finely orchestrated order of events that primes broken DNA for repair. We provide a comprehensive model for the hierarchical assembly of DSB condensates to explain DNA end synapsis and the recruitment of effector proteins for DNA damage repair.

Repairing Volumetric Muscle Loss with Commercially Available Hydrogels in an Ovine Model.

Volumetric muscle loss (VML) is the loss of skeletal muscle that exceeds the muscle's self-repair mechanism and leads to permanent functional deficits. In a previous study, we demonstrated the ability of our scaffold-free, multiphasic, tissue-engineered skeletal muscle units (SMUs) to restore muscle mass and force production. However, it was observed that the full recovery of muscle structure was inhibited due to increased fibrosis in the repair site. As such, novel biomaterials such as hydrogels (HGs) may have significant potential for decreasing the acute inflammation and subsequent fibrosis, as well as enhancing skeletal muscle regeneration following VML injury and repair. The goal of the current study was to assess the biocompatibility of commercially available poly(ethylene glycol), methacrylated gelatin, and hyaluronic acid (HA) HGs in combination with our SMUs to treat VML in a clinically relevant large animal model. An acute 30% VML injury created in the sheep peroneus tertius (PT) muscle was repaired with or without HGs and assessed for acute inflammation (incision swelling) and white blood cell counts in blood for 7 days. At the 7-day time point, HA was selected as the HG to use for the combined HG/SMU repair, as it exhibited a reduced inflammation response compared to the other HGs. Six weeks after implantation, all groups were assessed for gross and histological structural recovery. The results showed that the groups repaired with an SMU (SMU-Only and SMU+HA) restored muscle mass to greater degree than the groups with only HG and that the SMU groups had PT muscle masses that were statistically indistinguishable from its uninjured contralateral PT muscle. Furthermore, the HA HG, SMU-Only, and SMU+HA groups displayed notable efficacy in diminishing pro-inflammatory markers and showed an increased number of regenerating muscle fibers in the repair site. Taken together, the data demonstrates the efficacy of HA HG in decreasing acute inflammation and fibrotic response. The combination of HA and our SMUs also holds promise to decrease acute inflammation and fibrosis and increase muscle regeneration, advancing this combination therapy toward clinically relevant interventions for VML injuries in humans.

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair.

JOURNAL/nrgr/04.03/01300535-202501000-00036/figure1/v/2024-05-14T021156Z/r/image-tiff Axonal regeneration following surgical nerve repair is slow and often incomplete, resulting in poor functional recovery which sometimes contributes to lifelong disability. Currently, there are no FDA-approved therapies available to promote nerve regeneration. Tacrolimus accelerates axonal regeneration, but systemic side effects presently outweigh its potential benefits for peripheral nerve surgery. The authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site, with suitable properties for scalable production and clinical application, aiming to promote nerve regeneration and functional recovery with minimal systemic drug exposure. Tacrolimus is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 days. Size and drug loading are adjustable for applications in small and large caliber nerves, and the wrap degrades within 120 days into biocompatible byproducts. Tacrolimus released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80% compared with systemic delivery. Given its surgical suitability and preclinical efficacy and safety, this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

Outcome of Flexor Tendon Repair Using Eight-Strand Core Stitch Without Postoperative Finger Splinting.

There are no reports that detail clinical outcomes using the 8-strand suture techniques and early active mobilization. We aim to report the outcome of using an 8-strand double-cruciate core suture followed by early active motion without finger splinting. Thirty-five patients with 41 affected digits were operated and followed up for at least 6 months. A double cruciate repair with 4 single cross-grasping stitches on either side was employed. Active full-range finger flexion/extension exercises were allowed from the third postoperative day with the wrist held in the neutral position. The total active motion (TAM) calculated for the proximal interphalangeal and distal interphalangeal joints averaged 151° ± 22°, and the TAM% averaged 86% ± 13%. Based on the original Strickland-Glocovac criteria, excellent and good outcomes were achieved in 25 of 29 fingers (86.2%). An average extension lag of 21° ± 11° (range 10°-40°) was observed in 11 (38%) fingers. The Buck-Gramcko scale showed excellent and good results in 10 (83.4%) thumbs. Active interphalangeal range of motion averaged 68° ± 23°. An average extension lag of 12° ± 4° (range 10°-20°) was observed in 7 (58%) thumbs. Complications occurred in 4 thumbs, including bowstringing (2), rupture (1), and flexion contracture of 60° (1). Using the 8-strand repair technique and active mobilization performed by the patient is both practical and cost-saving. Intensive supervision of a hand therapist is generally not required. Notably improved outcomes have been achieved while preventing adhesions at the repair site. Further clinical outcome studies devoted specifically to the flexor pollicis longus are recommended to validate early-phase active mobilization following the 8-strand repair.

Study on injectable chitosan hydrogel with tendon-derived stem cells for enhancing rotator cuff tendon-to-bone healing

To explore the effect of chitosan (CS) hydrogel loaded with tendon-derived stem cells (TDSCs; hereinafter referred to as TDSCs/CS hydrogel) on tendon-to-bone healing after rotator cuff repair in rabbits. TDSCs were isolated from the rotator cuff tissue of 3 adult New Zealand white rabbits by Henderson step-by-step enzymatic digestion method and identified by multidirectional differentiation and flow cytometry. The 3rd generation TDSCs were encapsulated in CS to construct TDSCs/CS hydrogel. The cell counting kit 8 (CCK-8) assay was used to detect the proliferation of TDSCs in the hydrogel after 1-5 days of culture in vitro, and cell compatibility of TDSCs/CS hydrogel was evaluated by using TDSCs alone as control. Another 36 adult New Zealand white rabbits were randomly divided into 3 groups ( n=12): rotator cuff repair group (control group), rotator cuff repair+CS hydrogel injection group (CS group), and rotator cuff repair+TDSCs/CS hydrogel injection group (TDSCs/CS group). After establishing the rotator cuff repair models, the corresponding hydrogel was injected into the tendon-to-bone interface in the CS group and TDSCs/CS group, and no other treatment was performed in the control group. The general condition of the animals was observed after operation. At 4 and 8 weeks, real-time quantitative PCR (qPCR) was used to detect the relative expressions of tendon forming related genes (tenomodulin, scleraxis), chondrogenesis related genes (aggrecan, sex determining region Y-related high mobility group-box gene 9), and osteogenesis related genes (alkaline phosphatase, Runt-related transcription factor 2) at the tendon-to-bone interface. At 8 weeks, HE and Masson staining were used to observe the histological changes, and the biomechanical test was used to evaluate the ultimate load and the failure site of the repaired rotator cuff to evaluate the tendon-to-bone healing and biomechanical properties. CCK-8 assay showed that the CS hydrogel could promote the proliferation of TDSCs ( P<0.05). qPCR results showed that the expressions of tendon-to-bone interface related genes were significantly higher in the TDSCs/CS group than in the CS group and control group at 4 and 8 weeks after operation ( P<0.05). Moreover, the expressions of tendon-to-bone interface related genes at 8 weeks after operation were significantly higher than those at 4 weeks after operation in the TDSCs/CS group ( P<0.05). Histological staining showed the clear cartilage tissue and dense and orderly collagen formation at the tendon-to-bone interface in the TDSCs/CS group. The results of semi-quantitative analysis showed that compared with the control group, the number of cells, the proportion of collagen fiber orientation, and the histological score in the TDSCs/CS group increased, the vascularity decreased, showing significant differences ( P<0.05); compared with the CS group, the proportion of collagen fiber orientation and the histological score in the TDSCs/CS group significantly increased ( P<0.05), while there was no significant difference in the number of cells and vascularity ( P>0.05). All samples in biomechanical testing failed at the repair site during the testing process. The ultimate load of the TDSCs/CS group was significantly higher than that of the control group ( P<0.05), but there was no significant difference compared to the CS group ( P>0.05). TDSCs/CS hydrogel can induce cartilage regeneration to promote rotator cuff tendon-to-bone healing.

Exuberant circumferential fibroproliferative neuromas in lipomatosis of nerve: a unifying theory. Illustrative case.

Lipomatosis of nerve (LN) is a rare disorder characterized by the massive enlargement of peripheral nerves, frequently accompanied by generalized fibroadipose proliferation and skeletal overgrowth. The authors have been routinely following a 20-year-old male for lipomatosis of median nerve at the wrist noted shortly after birth. He had undergone resection of the lesion accompanied by sural nerve grafting at another institution. Clinically, although his neurological loss of function has been stable, he has had continued soft tissue growth. Serial magnetic resonance imaging has revealed persistent LN proximal to the repair sites with evidence of fatty proliferation in the sural grafts and continued LN and fatty proliferation distally. There has been a progressive circumferential pattern of fibrosis around the proximal and distal suture lines, which has a similar radiological pattern to desmoid type fibromatosis (a pattern recently described in neuromuscular choristoma [NMC] desmoid-type fibromatosis). Considering the similar reaction of nerve in both LN and NMC despite differing genetic cascades, the authors believe a unifying process occurs in both lesions. The pattern of circumferential fibroproliferation would be most consistent with neuron-mediated growth from unspecified trophic factors, supporting a previously reported a nerve-derived "inside-out mechanism." The clinical consequences of this unifying process are presented.

Ad-hoc train-arrival notification system for railway safety in remote areas

In the last few years, a particular interest in using wireless technologies in the industrial domain in order to automate processes and increase the level of safety has been noticed. This paper introduces an affordable mobile system to notify railway workers in rural areas about the approach of trains, and thus, to enhance their safety allowing for the early evacuation of repair sites located near the rails. The system comprises three key elements: a train device, a portable station device, and wearable devices for the workers. The communication methods and the underlying protocols between these components are discussed in detail. The system has been developed for freight trains of the national railway company of Kazakhstan and has undergone extensive testing for each of its components before its final trial. The preliminary results demonstrate that the system meets the requirements in terms of evacuation time, range, and portability, while exhibiting a very low cost of manufacturing. More specifically, the system can achieve a reliable communication range of several kilometers and a maximum response time of 2.3 s. The cost does not exceed $500 for a set of train, station, and 5 worker devices.

The Visitor’s Hut: An Integrative Methodology

International collaborative projects can export inequalities and power dynamics across borders. The Visitor’s Hut offers transformative possibilities in knowledge recovery that advance other ways of knowing through its active, other-seeking dialogic approach. Visiting prioritizes more equitable and community-grounded ways to mitigate power imbalances in international design research, where the methodology can become the site for repair by negotiating and translating, through design. In this paper, I showcase the methodology, first theorized in my PhD thesis and further put into practice through research on weaving ecologies in Myanmar, illustrating how knowledge is dynamic, created alongside others in a shared third space between cultures, languages, and people. This ongoing decolonization discussion invites us, as academic researchers, scholars, and practitioners, to actively reflect upon ‘me’, ‘us’, and ‘them’ within different temporal dimensions, remote relations, and the increasing use of technology.

Repair of chronic and large rotator cuff tears using extra-synovial autografts: An experimental study in rabbits.

To investigate whether and how extra-synovial autografts can enhance the reconstruction of chronic and large rotator cuff tears in a rabbit subscapularis model. Twenty rabbits were used to create a large subscapularis tear bilaterally. Six weeks later, the right shoulder of each rabbit was operated to repair the tear with an extra-synovial autograft, whereas the left shoulder did not undergo any surgery. At 6 and 12 weeks after the second procedure, the specimens underwent biomechanical and histological evaluation. Six more rabbits were used only as a normal reference. Biomechanical evaluation demonstrated that the ultimate load to failure of the Graft group (184.1 ± 35.7 N) was significantly higher (p = 0.04) than that of the Defect group (144.5 ± 32.2 N) at 12 weeks after repair, rising to 76% of the normal subscapularis tendon tensile strength. Histological analysis revealed an enhanced healing environment with neoangiogenesis and decreased inflammatory response at the repair site. Moreover, the tendon maturing score of the Graft group increased substantially from 6 (15.8 ± 0.9) to 12 (23.1 ± 0.6) weeks after repair (p = 0.01). In vivo data support the efficacy of extra-synovial autograft interposition in repairing chronic and large rotator cuff tears in a rabbit subscapularis model. The autografts were capable of enhancing the biomechanical properties of the repaired tendons, as evidenced by increased tensile strength, and forming new connective tissue simulating a fibrocartilage zone, as revealed by histological evaluation. N/A.

Use of Biodegradeable Temporizing Matrix Dermal Template for Reconstruction of Upper Extremity Soft Tissue Defects with Associated Tendon Injury.

In cases of complex upper extremity soft tissue defects with exposed bone or tendon, the surgeon needs to consider both restoration of stable soft tissue coverage and functional outcomes, which requires early motion and a wound bed suitable for tendon gliding. Often, local, regional, or free flaps are necessary; however, good outcomes have also been reported after staged reconstruction with a dermal template and split-thickness skin grafting. To our knowledge, staged reconstruction with a dermal template has not been described for soft tissue defects with an associated underlying tendon injury requiring tenorrhaphy. We have previously reported our experience with a synthetic dermal template [Novosorb BTM (Biodegradable Temporizing Matrix), Polynovo North America LLC. Carlsbad, Calif.] for the reconstruction of complex upper extremity defects with exposed tendon and showed that it consistently and reliably integrates even when these patients were treated with an early, active therapy protocol. As a result of these findings, we hypothesized that BTM could potentially be used over a tendon repair site without compromising functional outcomes. Here, we report on clinical outcomes for two patients with upper extremity injury where BTM was applied directly over a tendon repair or transfer site and resulted in stable soft tissue coverage with excellent tendon gliding. These early results show that this approach might be considered as an alternative to autologous tissue reconstruction in these patients and could reduce donor site morbidity associated with flap harvest.

Anaesthetic Management for Charcot Joint Surgery in a Previously Operated Meningomyelocele Patient: A Case Report

Charcot joint, a degenerative condition characterised by bone and joint destruction, often requires surgical intervention to alleviate pain and prevent complications. However, when this condition coexists with a history of meningomyelocele repair, additional considerations are necessary to ensure patient safety. The anaesthesia management for Charcot joint surgery in a meningomyelocele patient who has previously undergone surgery presents a unique challenge. Preoperative assessment should involve a comprehensive evaluation of the patient’s medical history, including previous surgical procedures, neurological status, and associated co-morbidities. Given the possible problems such as scarring, adhesion, and altered anatomy that may affect the choice of anaesthetic approach and airway management, particular attention should be paid to the site of the meningomyelocele repair. Here, the authors report a case of failed spinal anaesthesia in a 20 years old male patient with a history of operating meningocele who underwent surgery for Charcot’s joint. Charcot’s joint is a rare complication of syringomyelia or meningomyelocele, which can cause severe neurological deficits and deformities. Surgery is often required to correct the deformity and relieve the symptoms. Spinal anaesthesia is a commonly used technique for surgeries involving the lower limbs. This abstract highlights anaesthetic management in patients with Charcot joint and a history of meningomyelocele repair.

Osnovni principi otkrivanja oštećenja DNK pomoću alkalnog komet testa

The Comet assay is a highly sensitive and rapid method for detecting DNA damage at the level of individual cells. It measures single-stranded and double-stranded DNA breaks, alkali-labile, incomplete excision repair and cross-linking sites. A major advantage of the Comet assay is its applicability to both proliferating and non-proliferating cells, and it can be performed on all types of eukaryotic cells. The basic principle of the alkaline Comet assay is to lyse the biological membranes to release proteins bound to the DNA, followed by a short-term electrophoresis at a pH above 13. Through this process, the DNA fragments migrate and form a comet-like shape, which is visualized by staining with a DNA-binding fluorescent dye. The extent of electrophoretic migration is proportional to the amount of DNA damage. Key advantages of the Comet assay include sensitivity-the assay can detect low levels of DNA damage, versatility-it can be used with a small amount of test substance, speed-results are usually available within 24 to 48 hours, and broad applicability-the method is suitable for numerous purposes, including molecular epidemiology, occupational exposure studies, environmental biomonitoring, antigenotoxicity assessments and clinical research. Overall, the Comet assay provides valuable data for a range of scientific and clinical fields, making it a versatile and powerful tool for assessing DNA damage.

ИССЛЕДОВАНИЕ ФИЗИКО-МЕХАНИЧЕСКИХ СВОЙСТВ ПОЛИУРЕТАНОВЫХ КОМПАУНДОВ ДЛЯ ОЦЕНКИ ВОЗМОЖНОСТИ ИХ ПРИМЕНЕНИЯ В МЕМБРАННО-ПОРШНЕВОМ НАСОСЕ

The diaphragms in diaphragm piston pumps serve as the main working parts, the failure of which entails the shutdown of the entire pump, and, as a result, the sprayer, which leads to a decrease in the efficiency of agricultural activities and an increase in the cost of restoring the operability of agricultural equipment. The relevance of using the technology of free casting of twocomponent polyurethane in silicone molds in the organization of repair sites is due to the high quality of the parts obtained with a significant reduction in cost, as well as production time. Since the main reason for the failure of the membrane is abrasive wear and cyclic loads, the determining properties are hardness, strength and ductility of the materials used. (Research purpose) The research purpose is assessing the hardness, strength and plasticity of polyurethane compounds of various brands, depending on the production conditions of the sample, and concluding their applicability to manufacture piston pump diaphragms by free casting. (Materials and methods) Presented studies of hardness, tensile strength and elongation at break of three grades of polyurethane compounds PolyFlex 80A, Advaform Mark 80 and Silagerm 6080, depending on the technological modes of manufacturing samples from them. (Results and discussion) It was found that the curing of polyurethane compounds at higher temperatures allows for high strength and plastic properties of the material. It was noted that during curing, molecules are redistributed into the most favorable energy configurations, which exclude the appearance of structural stress concentrators, increasing the plasticity and strength of the material. The increased temperature helps to remove residual stresses in the material that occur during shrinkage. (Conclusions) The application scope of the research results is the manufacture of polymer parts of agricultural machinery, in particular, diaphragm diaphragm piston pump.

Biologically Enhanced Patch in the Healing and Mechanical Stability of Rotator Cuff Tears.

Biological patches have emerged as promising adjuncts in the surgical management of rotator cuff tears, aiming to enhance tissue healing and biomechanical properties of repaired tendons. These patches, derived from human or animal sources such as dermis or small intestinal submucosa, undergo mechanical and pathological changes within the rotator cuff environment post-implantation. These patches provide structural reinforcement to the repair site, distributing forces more evenly across the tendon and promoting a gradual load transfer during the healing process. This redistribution of forces helps alleviate tension on the repaired tendon and surrounding tissues, potentially reducing the risk of re-tears and improving overall repair integrity. Moreover, biological patches serve as scaffolds for cellular infiltration and tissue ingrowth, facilitating the recruitment of cells and promoting collagen synthesis. The integration of these patches into the host tissue involves a cascade of cellular events, including inflammation, angiogenesis, and matrix remodeling. Inflammatory responses triggered by patch implantation contribute to the recruitment of immune cells and the release of cytokines and growth factors, fostering a microenvironment conducive to tissue repair. However, despite their potential benefits, the long-term efficacy and durability of biological patches in rotator cuff repair remain areas of ongoing research and debate. Further studies are needed to elucidate the optimal patch characteristics, surgical techniques, and rehabilitation protocols to maximize clinical outcomes and minimize complications in rotator cuff surgery.

Chronic Achilles Tendon Avulsion Repair: Central Third Fascia Slide Technique with Flexor Hallucis Longus Transfer.

Chronic Achilles Tendon Avulsion Repair: Central Third Fascia Slide Technique with Flexor Hallucis Longus Transfer.

Nup153 is not required for anchoring heterochromatic DSBs to the nuclear periphery.

Pericentromeric heterochromatin mostly comprises repeated DNA sequences prone to ectopic recombination. In Drosophila cells, 'safe' homologous recombination repair requires relocalization of heterochromatic repair sites to the nuclear periphery before Rad51 recruitment and strand invasion. DSBs are anchored to the nuclear periphery through the Nup107/160 nucleoporin complex. Previous studies suggested that the nuclear pore 'basket' protein Nup153 could also mediate anchoring, but Nup153 RNAi depletion also affects Nup107 association with the pores, preventing a direct assessment of Nup153 role. Using a separation of function mutant, here we show that Nup153 is not required for anchoring heterochromatic DSBs to the nuclear periphery.

Harmonin homology domain-mediated interaction of RTEL1 helicase with RPA and DNA provides insights into its recruitment to DNA repair sites.

The regulator of telomere elongation helicase 1 (RTEL1) playsrolesin telomere DNA maintenance, DNA repair, and genome stability by dismantling D-loops and unwinding G-quadruplex structures. RTEL1 comprises a helicase domain, two tandem harmonin homology domains 1&2 (HHD1 and HHD2), and a Zn2+-binding RING domain. In vitro D-loop disassembly by RTEL1 is enhanced in the presence of replication protein A (RPA). However, the mechanism of RTEL1 recruitment at non-telomeric D-loops remainsunknown. In this study, we have unravelled a direct physical interaction between RTEL1 and RPA. Under DNA damage conditions, we showed that RTEL1 and RPA colocalise in the cell. Coimmunoprecipitation showed that RTEL1 and RPA interact, and the deletion of HHDs of RTEL1 significantly reduced this interaction. NMR chemical shift perturbations (CSPs) showed that RPA uses its 32C domain to interact with the HHD2 of RTEL1.Interestingly, HHD2 also interacted with DNA in thein vitro experiments. HHD2 structure was determined using X-ray crystallography, and NMR CSPs mapping revealed that both RPA32C and DNAcompetitivelybind toHHD2 on an overlapping surface. These results establish novel roles of accessory HHDs in RTEL1's functionsand provide mechanistic insights into the RPA-mediated recruitment of RTEL1to DNA repairsites.

МЕТОДЫ ОПРЕДЕЛЕНИЯ КОЛИЧЕСТВА И СОСТАВА РЕМОНТНЫХ БРИГАД ПРИ ВОССТАНОВЛЕНИИ ТЕХНИКИ

Energy resources (ES) that are part of the machine and tractor fleet, agricultural enterprise (Agricultural Enterprise), subject to intensive use, constantly need to maintain their working condition. The main problems of maintenance and repair of electrical systems and methods for solving them have been identified. A scheme for planning repairs at agricultural storage facilities has been determined. In conditions of limited time, medium and major repairs are proposed to be carried out by reassembly or by the aggregate-sectional method. It has been established that the main technical characteristics of the quality of repair bodies are the following indicators: the complexity of performing a certain type of repair on a given type of electrical system; repair cycle; repair intensity; working time fund. They are determined analytically and make it possible to evaluate the quality characteristics of repair bodies, determine the number and composition of repair teams at the enterprise, the list of repair work, etc. The norms for time expenditure (labor intensity) for performing each individual repair operation, which are also the norms for the production of repairmen, are determined in the process of repairing equipment by timing. When statistically processing the results of timing the time of repair work, the estimated norms of labor costs for individual types of work and the total costs of performing current, medium and major repairs for each type of electrical system are determined. Then the following is determined: lists of necessary equipment, instrumentation, equipment, tools and spare parts; technology of repair work; the required number of repair teams, workshops, workshops, sites, work areas and repair specialists; duration of the repair cycle; production standards for repair specialists; intensity of repairs; list of specialties, qualification level and productivity of each repairman. The implementation of theoretically based methods for determining the number and composition of repair teams when restoring power supply systems will expand the capabilities of the enterprise's repair bodies to restore equipment with faults of various types.

Cold compared with room temperature compress on the repaired primiparous perineum following injury at normal vaginal delivery: a randomized controlled trial

The perineum is typically injured at the first vaginal birth. The application of a cold compress to the perineal repair site can reduce pain; however, the effect usually dissipates after a couple of hours. Repeated applications may be needed for sustained analgesia. However, the medium-term effect of repeated applications of cold compress on the perineal repair site on the recovery of sexual function and perineal healing is not known. This study aimed to evaluate repeated applications of cold vs room temperature (placebo control) compress to the repaired primiparous perineum on pain upon movement. A randomized controlled trial was conducted in a university hospital in Malaysia from May 2022 to February 2023. A total of 224 women with a repaired episiotomy or spontaneous second-degree tear sustained at normal delivery were randomized as follows: 113 to frozen gel pack and 111 to room temperature gel pack, as wound compress. The compress was applied to the perineal repair site at 3 timepoints: immediately after repair, and at 4 and 8 hours after delivery, for 20 minutes at each application. The primary outcomes were pain during movement at 12 and 24 hours after delivery, scored using the 0 to 10 numerical rating scale. The secondary outcomes include duration of hospital stay; analgesic consumption; recovery and functional metrics of reestablishing flatus, mobilization, and urination, breastfeeding; maternal satisfaction with the allocated compress; and after hospital discharge for up to 6 weeks after birth through telephone interview, analgesic consumption, perineal pain, resumption of vaginal sex, and women's perception of perineal wound healing. The median (interquartile range) of pain at movement scores were 4 (4-5) vs 5 (4-5) (P=.018) at 12 hours and 2 (1-3) vs 2 (2-3) (P=.173) at 24 hours after birth for cold vs room temperature compress, respectively. Maternal satisfaction scores were 8 (7-9) vs 7 (6-8) (P=.119), oral analgesic for perineal pain while at the postnatal ward was taken by 94 of 113 (83.2%) vs 85 of 109 (78.0%) (relative risk, 1.07; 95% confidence interval, 0.94-1.21), and time to the first satisfactory breastfeeding episode was 11.6 (7.9-15.5) vs 13.0 (8.0-20.7) hours (P=.303) for cold vs room temperature compress, respectively. At 2 weeks telephone follow-up, analgesic intake and perineal pain were not different. At 6 weeks, analgesic intake, perineal pain, resumption of vaginal sex, exclusive breastfeeding, and maternal perception of perineal healing were not different. Intermittent cold compress in the first 8 hours to the repaired perineum reduces pain at 12 hours but the effect attenuates by 24 hours. Maternal satisfaction with their allocated compress was not different. There was no suggestion of harm or benefit on the other secondary outcomes.