Primary Defect Research Articles

Lean-and-Green Strength Performance Optimization of a Tube-to-Tubesheet Joint for a Shell-and-Tube Heat Exchanger Using Taguchi Methods and Random Forests

The failing tube-to-tubesheet joint is identified as a primary quality defect in the fabrication of a shell-and-tube heat exchanger. Operating in conditions of high pressure and temperature, a shell-and-tube heat exchanger may be susceptible to leakage around faulty joints. Owing to the ongoing low performance of the adjacent tube-to-tubesheet expansion, the heat exchanger eventually experiences malfunction. A quality improvement study on the assembly process is necessary in order to delve into the tight-fitting of the tube-to-tubesheet joint. We present a non-linear screening and optimization study of the tight-fitting process of P215NL (EN 10216-4) tube samples on P265GH (EN 10028-2) tubesheet specimens. A saturated fractional factorial scheme was implemented to screen and optimize the tube-to-tubesheet expanded-joint performance by examining the four controlling factors: (1) the clearance, (2) the number of grooves, (3) the groove depth, and (4) the tube wall thickness reduction. The adopted ‘green’ experimental tactic required duplicated tube-push-out test trials to form the ‘lean’ joint strength response dataset. Analysis of variance (ANOVA) and regression analysis were subsequently employed in implementing the Taguchi approach to accomplish the multifactorial non-linear screening classification and the optimal setting adjustment of the four investigated controlling factors. It was found that the tube-wall thickness reduction had the highest influence on joint strength (55.17%) and was followed in the screening hierarchy by the number of grooves (at 30.47%). The groove depth (at 7.20%) and the clearance (at 6.84%) were rather weaker contributors, in spite of being evaluated to be statistically significant. A confirmation run showed that the optimal joint strength prediction was adequately estimated. Besides exploring the factorial hierarchy with statistical methods, an algorithmic (Random Forest) approach agreed with the leading effects line-up (the tube wall thickness and the number of grooves) and offered an improved overall prediction for the confirmation-run test dataset.

Unrecognized Patent Foramen Ovale in Patient With Sinus Venosus-Type Atrial Septal Defect With Partial Anomalous Pulmonary Venous Return.

Unrecognized Patent Foramen Ovale in Patient With Sinus Venosus-Type Atrial Septal Defect With Partial Anomalous Pulmonary Venous Return.

Long-term management of children with tracheo-oesophageal fistula

Tracheoesophageal fistula with or without oesophageal atresia (TOF/OA) is a common congenital anomaly of the aero-digestive system. Timely diagnosis of the primary structural defect and later identification of complications are key to ensuring good outcomes. This short article outlines the epidemiology and natural history of TOF and offers practical advice to healthcare professionals to assist them in diagnosis, initial and longer-term management. The structural and functional features of TOF/OA are discussed alongside the associated conditions (including tracheomalacia and gastro-oesophageal reflux) and attendant clinical features. Following surgical correction post-operative and longer-term complications and sequelae are relatively common and include stricture, recurrent respiratory infections, cough, wheeze, dysphagia and gastroesophageal reflux disease. We highlight the importance of taking a multidisciplinary approach to managing children with TOF.

The Facial Artery Perforator Flap.

Reconstruction of facial melanoma defects can be challenging. Large defects of the midface, cheek, and nasolabial fold are often reconstructed using a cervicofacial flap which requires significant flap elevation and undermining. Surgeons are often hesitant to commit to such a large reconstruction without definitive pathologic evidence of negative margins. However, local perforator flaps may be used as an alternative to large flaps with less dissection and donor site morbidity and may also allow for more facile re-advancement in the event of a positive margin on final pathology. The goal of this study is to evaluate a perforator flap based on the facial artery to determine if it is a safe and cosmetically favorable option to immediately repair oncologic-related defects on the cheek and midface. A retrospective review of all melanoma cases performed by the senior author between January 2016 and December 2021 was conducted. Patients who underwent reconstruction using a facial artery perforator flap were included. Sixteen patients were included in our cohort. The average age was 67.3 years and 53% (n=8) were female. Fourteen patients had the primary defect located on the cheek, 1 from the nasolabial fold, and 1 from the distal nasal sidewall. All patients received immediate reconstruction. Excisional margins ranged from 0.5 to 2cm. Two patients had positive margins following pathology results with one undergoing treatment with imiquimod and the other opting for re-excision. No complications involving the defect or donor site were reported after an average follow-up time of 113.8 days. The facial artery perforator flap is a safe and cosmetically favorable option to immediately repair oncologic-related defects on the cheek and midface.

Aging and Food Restriction Alter Some Indices of Bone Metabolism in Male Rhesus Monkeys (Macaca mulatta)

Food restriction increases life span, reduces aging rate and affects a wide variety of biological functions. In rats, food restriction delays bone growth and reduces bone density and mineral content. We report the effects of aging and long-term (>6.0 y) food restriction on several indices of bone growth and metabolism in rhesus monkeys (Macaca mulatta). Food allotments for controls approximated free access consumption, whereas food-restricted monkeys received 30% less food on a body weight basis. Cross-sectional and longitudinal age effects on serum alkaline phosphatase paralleled those reported for humans. Food restriction induced a significant delay in the developmental decline (to adult levels) in total alkaline phosphatase and significantly suppressed serum interleukin 6 concentrations, particularly in younger monkeys. Also, food restriction slowed skeletal growth, as reflected by shorter crown-rump length, and significantly reduced total body bone mineral content, but not bone mineral density, measured by dual energy X-ray absorptiometry. Analyses of serum parathyroid hormone, calcium, phosphate and osteocalcin concentrations suggested that the effects on skeletal growth were not related to alterations in calcium and phosphate homeostasis or a primary defect in bone formation. These findings suggest that long-term food restriction delays skeletal development in male rhesus monkeys while allowing the development of a reduced but otherwise normal skeleton.

Triple Dufourmentel hexagonal flap for scalp reconstruction.

Transposition flaps are some of the most commonly used flaps for reconstructing scalp defects. Limberg first described his rhomboid transposition flap in 1946. Dufourmentel flap was an improved version of the Limberg flap published in 1962 in which the base of the flap is widened to improve vascularisation. Transposition flaps are one of the best known and most widely used transposition flaps in reconstructive surgery. They have proven successful in different types of reconstructive and aesthetic situations as a full-thickness random transposition flap. Combination of three Dufourmentel flaps to reconstruct hexagonal defects has not been reported in the literature. It is a modification of the triple Limberg flap, in which, after removing a hexagonal defect, we reconstruct the primary defect with a triple Dufourmentel flap. This flap is very useful for reconstructing large scalp defects as it provides a large amount of skin tissue with high viability; however, given its versatility, it could be used in other anatomical areas. Ann Med Surg (Lond) 2021 7:102544; Plast Reconstr Surg 2015 136:163-164; Atlas Oral Maxillofac Surg Clin North Am 2020 28:17-22.

DUX4 double whammy: The transcription factor that causes a rare muscular dystrophy also kills the precursors of the human nose.

SMCHD1 mutations cause congenital arhinia (absent nose) and a muscular dystrophy called FSHD2. In FSHD2, loss of SMCHD1 repressive activity causes expression of double homeobox 4 (DUX4) in muscle tissue, where it is toxic. Studies of arhinia patients suggest a primary defect in nasal placode cells (human nose progenitors). Here, we show that upon SMCHD1 ablation, DUX4 becomes derepressed in H9 human embryonic stem cells (hESCs) as they differentiate toward a placode cell fate, triggering cell death. Arhinia and FSHD2 patient-derived induced pluripotent stem cells (iPSCs) express DUX4 when converted to placode cells and demonstrate variable degrees of cell death, suggesting an environmental disease modifier. HSV-1 may be one such modifier as herpesvirus infection amplifies DUX4 expression in SMCHD1 KO hESC and patient iPSC. These studies suggest that arhinia, like FSHD2, is due to compromised SMCHD1 repressive activity in a cell-specific context and provide evidence for an environmental modifier.

A Variant In The HNF4A Gene Causing MODY-1 In A Teenage Girl: Optimal Glycaemic Control After Transition To Sulfonylurea

Maturity-Onset Diabetes of the Young (MODY) is a group of monogenic autosomal dominant forms of diabetes, characterized by early-onset of hyperglycemia, and typically the presence of a family history of diabetes in more than one generation. These features are also present in Type 1 and Type 2 Diabetes Mellitus, which frequently leads to misdiagnosis. There are various MODY subtypes, caused by mutations in 14 known genes, which share a primary defect in insulin secretion.

Tetrathiomolybdate Decreases the Expression of Alkaline Phosphatase in Dermal Papilla Cells by Increasing Mitochondrial ROS Production

Dermal papilla cells (DPCs) play important roles in hair growth regulation. However, strategies to regrow hair are lacking. Here, global proteomic profiling identified the tetrathiomolybdate (TM)-mediated inactivation of copper (Cu) depletion-dependent mitochondrial cytochrome c oxidase (COX) as the primary metabolic defect in DPCs, leading to decreased Adenosine Triphosphate (ATP) production, mitochondrial membrane potential depolarization, increased total cellular reactive oxygen species (ROS) levels, and reduced expression of the key marker of hair growth in DPCs. By using several known mitochondrial inhibitors, we found that excessive ROS production was responsible for the impairment of DPC function. We therefore subsequently showed that two ROS scavengers, N-acetyl cysteine (NAC) and ascorbic acid (AA), partially prevented the TM- and ROS-mediated inhibition of alkaline phosphatase (ALP). Overall, these findings established a direct link between Cu and the key marker of DPCs, whereby copper depletion strongly impaired the key marker of hair growth in the DPCs by increasing excessive ROS production.

A Broad Characterization of Glycogen Storage Disease IV Patients: A Clinical, Genetic, and Histopathological Study.

Glycogen storage disease type IV (GSD IV) is an ultra-rare autosomal recessive disease caused by variants in the GBE1 gene, which encodes the glycogen branching enzyme (GBE). GSD IV accounts for approximately 3% of all GSD. The phenotype of GSD IV ranges from neonatal death to mild adult-onset disease with variable hepatic, muscular, neurologic, dermatologic, and cardiac involvement. There is a paucity of literature and clinical and dietary management in GSD IV, and liver transplantation (LT) is described to correct the primary hepatic enzyme defect. Objectives: We herein describe five cases of patients with GSD IV with different ages of onset and outcomes as well as a novel GBE1 variant. Methods: This is a descriptive case series of patients receiving care for GSD IV at Reference Centers for Rare Diseases in Brazil and in the United States of America. Patients were selected based on confirmatory GBE1 genotypes performed after strong clinical suspicion. Results: Pt #1 is a Latin male with the chief complaints of hepatosplenomegaly, failure to thrive, and elevated liver enzymes starting at the age of 5 months. Before LT at the age of two, empirical treatment with corn starch (CS) and high protein therapy was performed with subjective improvement in his overall disposition and liver size. Pt #2 is a 30-month-old Afro-American descent patient with the chief complaints of failure to gain adequate weight, hypotonia, and hepatosplenomegaly at the age of 15 months. Treatment with CS was initiated without overall improvement of the symptoms. Pt #3.1 is a female Latin patient, sister to pt #3.2, with onset of symptoms at the age of 3 months with bloody diarrhea, abdominal distention, and splenomegaly. There was no attempt of treatment with CS. Pt #4 is an 8-year-old male patient of European descent who had his initial evaluation at 12 months, which was remarkable for hepatosplenomegaly, elevated ALT and AST levels, and a moderate dilatation of the left ventricle with normal systolic function that improved after LT. Pt #1, #3.2 and #4 presented with high levels of chitotriosidase. Pt #2 was found to have the novel variant c.826G > C p.(Ala276Pro). Conclusions: GSD IV is a rare disease with different ages of presentation and different cardiac phenotypes, which is associated with high levels of chitotriosidase. Attempts of dietary intervention with CS did not show a clear improvement in our case series.

Multimorbidities in Allergic Rhinitis-Current Evidence from Epidemiological Studies, Treatment Trials, and Molecular Data.

Given that allergic rhinitis (AR) commonly coexists with other diseases, the present narrative review attempts a brief presentation of current theories on multimorbidities in relation to phenotypes, genotypes, age, and treatment responses with the term "multimorbidities" indicating the uncertainty regarding the primary defect, organ, or pathophysiologic mechanism involved. Though age-related manifestations allow for the generation of several hypotheses on AR's specific mechanisms, the various theories regarding the initiation or the aggravation of atopic disorders have yet to be proved. Multimorbid AR seems to have a different genetic basis from "stand-alone" AR as well a more severe phenotype. Most studies on the treatment of AR and its multimorbidities focus on allergen immunotherapy, which improves the atopic symptoms and may play a preventive role in the onset of new allergen sensitizations. The use of biological factors may also have a beneficial effect, even though it has currently been approved only for some comorbidities of AR, such as asthma. Employing the use of phenotypes and genotypes concerning multimorbidity broadens current knowledge, but further research is needed to develop diagnostic, stratificational, and predictive algorithms for single and multimorbid allergic diseases (Fig.1). The real-time data obtained by mobile apps and the new insights on the pathophysiology of AR and its comorbidities will permit both timed preventive measures and better individualized and effective antiallergic treatment. Fig. 1 Current concepts and future trends in diagnosis and management of multimorbid allergic rhinitis.

Process exploration of β-Ga2O3 blind hole processing by water-assisted femtosecond laser technology

β-Ga2O3 is a promising high-performance material with broad application prospects in the micro-electro-mechanical-systems (MEMSs). It can be used in extreme environments such as ultralow temperatures and intense radiation, but its hardness, brittleness, and easy cleavage are the primary defect in processing. As a substrate material for the next generation of large-scale integrated circuits, blind hole processing of β-Ga2O3 has attracted intense attention. In this work, we investigated the blind hole on (010) β-Ga2O3 surfaces treated with a femtosecond-pulse laser at the wavelength of 1030 nm and the pulse width of 285 fs. Water-assisted fs laser micromachining is proposed to solve the deposition of pore debris within the hole in the air environment. Furthermore, the influence of laser pulse energy, laser pulse numbers, liquid layer thickness, and laser repetition rate on the surface morphology of the blind hole was studied by using the control variable method. The results show that precise processing of β-Ga2O3 blind holes can be achieved by controlling fs laser processing parameters. In this work, the proposed liquid-assisted fs laser machining was proved to be a reliable tool for performing high-quality β-Ga2O3 blind hole processing, which has important implications for device applications of β-Ga2O3 substrates.

Age-Related Dysfunction in Proteostasis and Cellular Quality Control in the Development of Sarcopenia

Sarcopenia is a debilitating skeletal muscle disease that accelerates in the last decades of life and is characterized by marked deficits in muscle strength, mass, quality, and metabolic health. The multifactorial causes of sarcopenia have proven difficult to treat and involve a complex interplay between environmental factors and intrinsic age-associated changes. It is generally accepted that sarcopenia results in a progressive loss of skeletal muscle function that exceeds the loss of mass, indicating that while loss of muscle mass is important, loss of muscle quality is the primary defect with advanced age. Furthermore, preclinical models have suggested that aged skeletal muscle exhibits defects in cellular quality control such as the degradation of damaged mitochondria. Recent evidence suggests that a dysregulation of proteostasis, an important regulator of cellular quality control, is a significant contributor to the aging-associated declines in muscle quality, function, and mass. Although skeletal muscle mammalian target of rapamycin complex 1 (mTORC1) plays a critical role in cellular control, including skeletal muscle hypertrophy, paradoxically, sustained activation of mTORC1 recapitulates several characteristics of sarcopenia. Pharmaceutical inhibition of mTORC1 as well as caloric restriction significantly improves muscle quality in aged animals, however, the mechanisms controlling cellular proteostasis are not fully known. This information is important for developing effective therapeutic strategies that mitigate or prevent sarcopenia and associated disability. This review identifies recent and historical understanding of the molecular mechanisms of proteostasis driving age-associated muscle loss and suggests potential therapeutic interventions to slow or prevent sarcopenia.

Microtubule stabilization targeting regenerative chondrocyte cluster for cartilage regeneration.

Purpose: Chondrocytes (CHs) in cartilage undergo several detrimental events during the development of osteoarthritis (OA). However, the mechanism underlying CHs regeneration involved in pathogenesis is largely unknown. The aim of this study was to explore the underlying mechanism of regeneration of CHs involved in the pathological condition and the potential therapeutic strategies of cartilage repair. Methods and Materials: CHs were isolated from human cartilage in different OA stages and the high-resolution cellular architecture of human osteoarthritis was examined by applying single-cell RNA sequencing. The analysis of gene differential expression and gene set enrichment was utilized to reveal the relationship of cartilage regeneration and microtubule stabilization. Microtubule destabilizer (nocodazole) and microtubule stabilizer (docetaxel) treated-human primary CHs and rats cartilage defect model were used to investing the effects and downstream signaling pathway of microtubule stabilization on cartilage regeneration. Results: CHs subpopulations were identified on the basis of their gene markers and the data indicated an imbalance caused by an increase in the degeneration and disruption of CHs regeneration in OA samples. Interestingly, the CHs subpopulation namely CHI3L1+ CHs, was characterized by the cell regenerative capacity, stem cell potency and the activated microtubule (MT) process. Furthermore, the data indicated that MT stabilization was effective in promoting cartilage regeneration in rats with cartilage injury model by inhibiting YAP activity. Conclusion: These findings lead to a new understanding of CHs regeneration in the OA pathophysiology context and suggest that MT stabilization is a promising therapeutic target for OA and cartilage injury.

Keloid Treatment Using Plasma Exeresis: A Pilot Trial Study

Introduction: Keloid scars and hypertrophic scars are more commonly seen after surgeries, suture placements, or other skin damages. Scars can be treated using a variety of methods, including topical compounds, surgery, and lasers. The aim of this study is to evaluate the effects of plasma exeresis on the treatment of keloid scars. Methods: This experimental study was conducted on patients with keloid scars, defined as a treatment-resistant subtype of scars with extension beyond the primary skin defect and cauliflower appearance, in different parts of the body. The patients were treated with 2-to-3-session plasma exeresis. Scars were examined based on the Vancouver scar scale (VSS) before and 5 months after the treatment. Results: A total number of 24 scars were enrolled in this study. The number of patients was 16. There was a decrease in the mean thickness of keloids from 2.20 to 0.54 (P=0.000). The mean pigmentation and pliability scores decreased from 1.54 and 2.16 to 0.375 and 0.541, respectively (P=0.001, 000). There was a significant reduction in the keloid scar vascularity score from 1.666 to 0.541 (P=0.000). There was a decrease from 0.708 to 0.00 (P=0.004) in the mean itchiness score. After the intervention, the mean pain score was 0.000, compared to 0.7500 before the intervention (P=0.003). There was a decrease in the total score from 8.958 to 2.000 (P=0.000). Conclusion: The plasma exeresis procedure is effective in destroying small keloid scars. Furthermore, results in less itching and pain, as well as no significant complications or recurrences.

Hemophagocytic lymphohistiocytosis: A scourge for the physician and bane to the bone marrow.

Hemophagocytic lymphohistiocytosis (HLH) is a condition characterized by hyperinflammation. It can occur due to primary genetic defect or secondary to other etiology such as infection and rheumatological conditions. Clinical features include fever, cytopenia, organomegaly and several laboratory abnormalities. It can be a life-threatening condition secondary to worsening cytopenia and multiorgan dysfunction. To study the clinical profile of HLH in a tertiary care hospital in Southern India. Our study has reviewed nine cases of HLH among adult patients presented over 5 years (2017-2022). The majority of our cases were secondary to infection and had a hospital stay over two weeks and with a good response to steroid and immunomodulators. We would like to stress upon the importance of awareness of such a condition so that there can be early suspicion and workup including bone marrow examination, enabling early initiating of specific therapy for this fatal condition.

Atrioesophageal Fistula: imaging for a definitive diagnosis

Aim: Atrial fibrillation is a common arrhythmia, with a prevalence of 37.574 million cases worldwide. Atrioesophageal fistula is a rare but potentially fatal complication of ablation of atrial fibrillation developing up to 60-days post-ablation with a prevalence of 0.07% to 0.25%, and a 63% mortality. While chest CTs are abnormal in most of these patients (76%-93%), definitive atrioesophageal fistula is noted in only 23-35% of cases, complicating pre-intervention diagnosis. Surgical repair of the left atrial and primary esophageal defect is essential for these patients, resulting in reduced mortality compared to nonsurgical management (33.71% vs. 94.19%). Methods: Our case series and comprehensive review of the literature highlights the diagnostic and treatment challenges of atrioesophageal fistula. Results/Conclusions: For symptomatic patients within 60-days post-ablation, IV contrast-enhanced helical chest CT with thin section collimation as initial imaging and axial reconstruction utilizing a 1mm-mm detector with sagittal and coronal reformats should be completed to allow for optimal identification of abnormalities consistent with atrioesophageal fistula. Patients with neurologic symptoms with the presence of pneumocephalus, infarcts involving one or more vascular territories, or diffuse air emboli that are highly suggestive of atrioesophageal fistula, warrant a chest CT with IV contrast to evaluate the presence of AEF. An initial unremarkable chest CT does not rule out atrioesophageal fistula and repeat chest CT with IV contrast within 1-3 days increases the likelihood of a definitive AEF diagnosis. Surgery is the only recommended management in patients with atrioesophageal fistula who are clinically stable enough to endure the procedures.

Лечение сочетанного огнестрельного ранения с дефектом плечевой кости и лучевого нерва (клиническое наблюдение)

Treatment of patients with gunshot bone and soft tissue defects of the extremities requires non-standard approaches and the participation of doctors of various specialties. The application of additive and microsurgical technologies allows one-stage restoration of bone defects and functionally important soft tissue formations. Objective: To demonstrate the possibilities of modern reconstructive-plastic surgery in combination with additive 3D-technology in the treatment of patients with severe gunshot wounds of the extremities. Clinical case: a patient with a combined wound of the chest and upper limb with a primary defect of the humerus and radial nerve. Treatment was based on damage control surgery (DCS) and damage control orthopedic (DCO) tactics. X-ray, computed tomography, and angiography were used for diagnostics and preoperative planning. Based on the CT data, a 3D model of the autograft, resection templates, and a metal structure for osteosynthesis were made. After stabilization of the general condition of the wounded man and elimination of the risk of infectious complications, a one-stage replacement of the radial nerve defect at the level of the middle third of the shoulder with a gastrocnemius nerve autograft was performed; the upper and middle third humeral bone defect was replaced with a free blood-supplied fibula autograft with osteosynthesis using an individual 3D plate with bacteriostatic hydroxyapatite spraying in combination with zinc. А positive anatomical and functional outcome was achieved in the treatment of a patient with a gunshot defect of the humerus and radial nerve. An individual complex approach combined with innovative technologies makes it possible to achieve good anatomical and functional results in the treatment of patients with primary combined limb gunshot defects.

Analysis of the dynamics of changes in gas content in oil-filled equipment with defects of various types

The article presents the results of analysing the dynamics of changes in the values of the ratios of characteristic gases, the percentage of gases, and defect nomograms in the process of developing electrical discharges, local overheating, and combined defects in high-voltage oil-filled equipment. During the analysis, the value of gas concentrations was evaluated for compliance with different levels regulated in the current Ukrainian standard at different stages of defect development. To determine the type of defect based on the values of the ratios of characteristic gases at different points in time, the norms regulated by the IEC 60599 standard and the ETRA square were used. The dynamics of changes in the percentage of gas was analysed using the Duval triangle. The results of the analysis showed that the primary defects during the development of electric discharges can be not only electric discharges with lower intensity, but also thermal (in particular, in the temperature range of 150-300 ℃) and combined defects. At the same time, in the process of discharge development, the nature of defects may change from measurement to measurement. Thus, when assessing the possibility of further operation of transformers, in addition to the degree of danger of the defect and the rate of its development, it is necessary to take into account the possibility of transforming the defect from a less to a more “dangerous” one that develops rapidly. During the development of thermal defects, the primary defect is usually a thermal defect with a lower hot spot temperature. It was found that in equipment with overheating above 700 ℃, the change in gas content during the development of the defect has a similar character. In particular, a mirror image of the change in the percentage of methane in relation to ethylene is observed. This effect can be used to detect high-temperature overheating at an early stage of its development, even before the gas concentrations exceed the limit values, which will help to avoid the destruction of equipment insulation and extend its service life. During the development of combined defects (overheating accompanied by discharges or discharges accompanied by heating), the main defect (e.g., discharge) first appears, and in the process of development, an additional defect (e.g., heating) develops. The results obtained indicate the possibility of detecting and recognizing defects in oil-filled equipment at different stages of their development.

Case of gunshot injury to the liver by a hand-made modified sniper bullet: organ-preserving surgical management with damage control tactics and transpapillary biliary decompression

Combat penetrating gunshot injuries are frequently associated with damage to the liver. A bile leak and an external biliary fistula (EBF) are typical complications. Biliary decompression is commonly applied for the management of EBF. Furthermore, there is insufficient data available regarding the characteristics of combat trauma and its management in the context of ongoing hybrid warfare in East Ukraine.
 A 23­year­old male was admitted with a thoracoabdominal penetrating gunshot wound (GSW) that was caused by a high­energy multiple metal projectile (a fragmented sniper bullet). Damage control tactics was applied at all 4 levels of military medical care. Endoscopic retrograde cholangiopancreatography (ERCP), endoscopic sphincterotomy, and placement of a biliary stent were used for evaluation and biliary decompression. Stent occlusion was treated with stent replacement and scheduled ERCP. Partial EBF was diagnosed based on the primary wound defect of the liver and was closed without surgical intervention on the 34th day after injury. Acute cholecystitis was associated with ERCP and was managed with cholecystostomy.
 The combination of operative and nonoperative techniques for the management of the combat GSW to the liver is effective, along with the application of damage control tactics. Scheduled ERCP is effective for the management of EBF, so liver resection can be avoided. The transpapillary intervention with stent placement was successfully used for biliary decompression. Early post­traumatic stent occlusion can be diagnosed and effectively managed by scheduled ERCP as well as stent replacement with a large­diameter stent inserted as close as possible to the site of bile leak.