Chemical synthesis and super capacitance performance of novel CuO@Cu4O3/rGO/PANI nanocomposite electrode.

Copper oxide-based nanocomposites are promising electrode materials for high-performance supercapacitors due to their unique properties that aid electrolyte access and ion diffusion to the electrode surface. Herein, a facile and low-cost synthesis in situ strategy based on co-precipitation and incorporation processes of reduced graphene oxide (rGO), followed by in situ oxidative polymerization of aniline monomer has been reported. CuO@Cu4O3/rGO/PANI nanocomposite revealed the good distribution of CuO@Cu4O3 and rGO within the polymer matrix which allows improved electron transport and ion diffusion process. Galvanostatic charge-discharge (GCD) results displayed a higher specific capacitance value of 508 F g-1 for CuO@Cu4O3/rGO/PANI at 1.0 A g-1 in comparison to the pure CuO@Cu4O3 278 F g-1. CuO@Cu4O3/rGO/PANI displays an energy density of 23.95 W h kg-1 and power density of 374 W kg-1 at the current density of 1 A g-1 which is 1.8 times higher than that of CuO@Cu4O3 (13.125 W h kg-1) at the same current density. The retention of the electrode was 93% of its initial capacitance up to 5000 cycles at a scan rate of 100 mV s-1. The higher capacitance of the CuO@Cu4O3/rGO/PANI electrode was credited to the formation of a fibrous network structure and rapid ion diffusion paths through the nanocomposite matrix that resulted in enhanced surface-dependent electrochemical properties.

Early-Outcome Differences between Acute and Chronic Periprosthetic Joint Infections-A Retrospective Single-Center Study.

Periprosthetic joint infections (PJI) are serious complications after arthroplasty, associated with high morbidity, mortality, and complex treatment processes. The outcomes of different PJI entities are largely unknown. The aim of this study was to access the early outcomes of different PJI entities. A retrospective, single-center study was conducted. The characteristics and outcomes of patients with PJI treated between 2018 and 2019 were evaluated 12 months after the completion of treatment. Primary endpoints were mortality, relapse free survival (RFS) and postoperative complications (kidney failure, sepsis, admission to ICU). A total of 115 cases were included [19.1% early (EI), 33.0% acute late (ALI), and 47.8% chronic infections (CI)]. Patients with ALI were older (p = 0.023), had higher ASA scores (p = 0.031), preoperative CRP concentrations (p = 0.011), incidence of kidney failure (p = 0.002) and sepsis (p = 0.026). They also tended towards higher in-house mortality (ALI 21.1%, 13.6% EI, 5.5% CI) and admission to ICU (ALI 50.0%, 22.7% EI, 30.9% CI). At 12 months, 15.4% of patients with EI had a relapse, compared to 38.1% in ALI and 36.4% in CI. There are differences in patient characteristics and early outcomes between PJI entities. Patients with EI have better early clinical outcomes. Patients with ALI require special attention during follow-up because they have higher occurrences of relapses and postoperative complications than patients with EI and CI.

Subtotal diaphyseal replacement of the femur with modular mega-endoprosthesis following interprosthetic fracture. A case report.

Mega-endoprostheses enable wide management options in the treatment of primary and periprosthetic fracture of the lower extremities. In this study, we report on the use of custom-made subtotal diaphyseal endoprosthetic replacement in treatment of interprosthetic femoral fracture. This procedure is off-label, but in this particular case, it was the safest and most stress-stable treatment option. The implant was delivered within three weeks. The surgical procedure for subtotal replacement of the femoral diaphysis was performed without any intra- or postoperative complication. The duration for the surgical intervention was one hour and 40 minutes. The patient was then mobilized with full weight bearing. At one-year follow-up, the patient did not complain of any pain. The Harris Hip Score HHS improved from 26 to 83 at one-year follow-up, the Western Ontario and McMaster Universities Osteoarthritis Index WOMAC improved from 88 to 16. Mega-endoprostheses enable a wide range of management options in the treatment of primary, peri- and interprosthetic fractures of the lower extremities. In many cases, an individual therapeutic plan is necessary ranging up to the use of custom-made implants.

Intramedullary arthrodesis of the knee joint with additional femoral neck screw to prevent periprosthetic fracture of the proximal femur. A case report.

Arthrodesis of the knee joint has proven effective in the treatment of chronic periprosthetic infections as well as in cases of previous multiple revision surgery after total knee replacement with insufficiency of the extensor apparatus. In this case report, we report on the use of a custom-made intramedullary arthrodesis nail of the knee joint following multiple revisions due to aseptic loosening after total knee replacement. Surgery was performed according to preoperative computerized planning. Microbiological and histological samples obtained intraoperatively showed no evidence of infection. Yet, the patient presented postoperatively with complete loss of active dorsiflexion of the ipsilateral foot. On one-year follow-up, the patient did not complain of any pain. The radiological findings one year after surgery showed no sign of loosening or any other pathological findings. The neurological lesion has completely recovered. The Harris Hip Score HHS improved from 24 (prior to implantation of the arthrodesis) to 75 on one-year follow-up, the Western Ontario and McMaster Universities Osteoarthritis Index WOMAC improved from 86 to 20. The particularity of this case lies in the fact that an additional femoral neck screw was brought in to prevent periprosthetic fracture of the proximal femur. Careful preoperative planning as well as surgical performance were necessary to adjust the rotation of the femoral nail to allow adequate positioning of the femoral neck screw. Intramedullary arthrodesis of the knee is a suitable management option following multiple revision surgery after total knee replacement with insufficiency of the extensor apparatus. In many cases, an individual therapeutic plan is necessary ranging up to the use of custom-made implants.

[The new medical licensing regulations (ÄApprO) : Status and expected challenges]. / Die neue Ärztliche Approbationsordnung ÄApprO : Aktueller Stand und zu erwartende Herausforderungen.

BackgroundThe amendment to the medical licensing regulations (ÄApprO) was decided at the federal level in the version of the "Master Plan for Medical Studies 2020" passed in 2017. In addition to the organizational effort involved in redesigning the curricular teaching, the expected costs associated with the implementation of the new licensing regulations due to the necessary additional time and, therefore, personnel expenditure are of particular importance. Taking into account the different forms of study and the 20% scope for study-design provided to the individual faculties, the process of transferring the teaching content to the new modules confronts us with an enormous organizational challenge.Significance of O&UDiseases of the musculoskeletal system are of particular medical, social and economic importance. Therefore, the training of future physicians in the field of orthopedics and traumatology must be taken into account. The visibility of the field of orthopedics and traumatology must not be lost with the introduction of the new medical licensing regulations (ÄApprO).ImplementationThe implementation of the new medical licensing regulations at German universities will be costly and necessitates an increased number of staff. However, there is a great opportunity to position orthopedics and traumatology as a "central player" in the modular, interdisciplinary and interprofessional course landscape. It is, therefore, important to take on concrete responsibility for the design of the new teaching programs and to bring in our specialist and interdisciplinary skills wherever sensible and possible.

Physical exercise as a treatment for persisting symptoms post-COVID infection: review of ongoing studies and prospective randomized controlled training study.

BACKGROUND AND PURPOSE: No evidence-based treatment is available for patients with persisting symptoms post-COVID-19 infection. We hypothesized that physical exercise may represent a safe and effective treatment option for post-COVID. METHODS: We performed a systematic search of the literature that revealed a lack of randomized training studies in patients post-COVID. Based on these findings, a prospective randomized controlled study with open-label and blinded endpoint evaluation was designed. 272 patients with symptoms of fatigue persisting over 6 weeks post-COVID infection were screened. Patients with pathological cardiovascular findings were excluded. 57 patients consented and were randomized to 4 weeks of supervised personalized strength and endurance training or usual care. The follow-up period was 3 and 6 months. RESULTS: There were no adverse events related to the training. Spiroergometry of the training group showed a significantly higher increase in VO2peak (10.0 ± 12.7% vs. 0.1 ± 8.9%, p < 0.01, respectively) and oxygen pulse (9.8 ± 10.8% vs. 0.0 ± 13.9%, p < 0.05, respectively). Parameters of the Multidimensional Fatigue Inventory-20, McGill Quality of Life Questionnaire, and Post-COVID-19 Functional Status were improved after 4 weeks in both groups. In the follow-up period, the total physical activity per week was significantly greater in the exercise group than in controls (1280 ± 1192 min vs. 644 ± 554 min, p < 0.05, respectively). The improvements in fatigue and quality of life were not statistically different between the training and usual care groups. CONCLUSION: Exercise is safe and improves maximal exercise capacity in post-COVID patients. Fatigue and quality of life improve over time in individuals that are willing to participate in a training study irrespective of their allocation. REGISTRATION: German Clinical Trials Register: DRKS00026686. Date of registration: 27.09.2021.

Phase holograms for the three-dimensional patterning of unconstrained microparticles.

Acoustic radiation forces can remotely manipulate particles. Forces from a standing wave field align microscale particles along the nodal or anti-nodal locations of the field to form three-dimensional (3D) patterns. These patterns can be used to form 3D microstructures for tissue engineering applications. However, standing wave generation requires more than one transducer or a reflector, which is challenging to implement in vivo. Here, a method is developed and validated to manipulate microspheres using a travelling wave from a single transducer. Diffraction theory and an iterative angular spectrum approach are employed to design phase holograms to shape the acoustic field. The field replicates a standing wave and aligns polyethylene microspheres in water, which are analogous to cells in vivo, at pressure nodes. Using Gor'kov potential to calculate the radiation forces on the microspheres, axial forces are minimized, and transverse forces are maximized to create stable particle patterns. Pressure fields from the phase holograms and resulting particle aggregation patterns match predictions with a feature similarity index > 0.92, where 1 is a perfect match. The resulting radiation forces are comparable to those produced from a standing wave, which suggests opportunities for in vivo implementation of cell patterning toward tissue engineering applications.

Cardiopulmonary effects of prolonged surgical abdominal retractors application during general anesthesia: a prospective observational comparative study

Abstract Introduction: Increasing abdominal pressures could affect pulmonary compliance and cardiac performance, a fact based on which the aim of the present study to detect the cardiopulmonary burden of multiple retractors application during supine versus lateral abdominal surgeries. We hypothesized that surgical ring multiple retractors application would affect the pulmonary and cardiac functions during both lateral and supine abdominal surgeries. Methods: Prospective observational comparative study on forty surgical patients subdivided into two groups twenty each, comparing pulmonary compliance and cardiac performance before, during and after retractors application, group (S) supine position cystectomy surgery, and group (L) lateral position nephrectomy surgery under general anesthesia, Composite 1ry outcome; dynamic compliance C-dyn and cardiac index CI and Other outcome variables ICON cardio-meter were also recorded. Results: C-dyn and C-stat were significantly decreased late during retractor application in lateral compared to supine surgery with significant decrease compared to basal values all over the surgical time. CI was significantly increased after retractor removal in both of the study groups compared to basal values. PAW P was significantly increased in -lateral compared to supine surgery -with significant increase compared to basal value all over the surgical time in both of the study groups. significant increase in DO2I compared to basal value during both supine and lateral positions. Conclusion: Surgical retraction results in a short-lived significant decreases in lung compliance and cardiac output particularly during the lateral-kidney position than the supine position compliance.

Medical studies in times of a pandemic - concepts of digital teaching for Orthopaedics and Trauma at german universities.

BACKGROUND: Due to the Covid-19 pandemic, on-site classroom teaching became limited at most German medical universities. This caused a sudden demand for digital teaching concepts. How the transfer from classroom to digital teaching or digitally assisted teaching was conducted was decided by each university and/or department individually. As a surgical discipline, Orthopaedics and Trauma have a particular focus on hands-on teaching as well as direct contact to patients. Therefore, specific challenges in designing digital teaching concepts were expected to arise. Aim of this study was to evaluate medical teaching at German universities one year into the pandemic as well as to identify potentials and pitfalls in order to develop possible optimization approaches. METHODS: A questionnaire with 17 items was designed and sent to the professors in charge of organising the teaching in Orthopaedics and Trauma at each medical university. A differentiation between Orthopaedics and Trauma was not made to allow a general overview. We collected the answers and conducted a qualitative analysis. RESULTS: We received 24 replies. Each university reported a substantial reduction of their classroom teaching and efforts to transfer their teaching to digital formats. Three sites were able to switch to digital teaching concepts completely, whereas others tried to enable classroom and bedside teaching at least for students of higher edcuational levels. The online platforms used varied depending on the university as well as the format it was supposed to support. CONCLUSION: One year into the pandemic significant differences concerning the proportions of classroom and digital teaching for Orthopaedics and Trauma can be observed. Simultaneously huge differences in concepts used to create digital teaching are present. Since a complete suspense of classroom teaching was never mandatory, several universities developed hygiene concepts to enable hands-on and bedside teaching. Despite these differences, some similarities were observed: the lack of time and personnel to generate adequate teaching material was reported as the leading challenge by all participants of this study.

Photoelectrochemical Performance of Strontium Titanium Oxynitride Photo-Activated with Cobalt Phosphate Nanoparticles for Oxidation of Alkaline Water.

Photoelectrochemical (PEC) solar water splitting is favourable for transforming solar energy into sustainable hydrogen fuel using semiconductor electrodes. Perovskite-type oxynitrides are attractive photocatalysts for this application due to their visible light absorption features and stability. Herein, strontium titanium oxynitride (STON) containing anion vacancies of SrTi(O,N)3-δ was prepared via solid phase synthesis and assembled as a photoelectrode by electrophoretic deposition, and their morphological and optical properties and PEC performance for alkaline water oxidation are investigated. Further, cobalt-phosphate (CoPi)-based co-catalyst was photo-deposited over the surface of the STON electrode to boost the PEC efficiency. A photocurrent density of ~138 µA/cm at 1.25 V versus RHE was achieved for CoPi/STON electrodes in presence of a sulfite hole scavenger which is approximately a four-fold enhancement compared to the pristine electrode. The observed PEC enrichment is mainly due to the improved kinetics of oxygen evolution because of the CoPi co-catalyst and the reduced surface recombination of the photogenerated carriers. Moreover, the CoPi modification over perovskite-type oxynitrides provides a new dimension for developing efficient and highly stable photoanodes in solar-assisted water-splitting reactions.

Review of natural compounds for potential psoriasis treatment.

Psoriasis represents an immune-mediated disease with an unclear cause that's marked by inflammation triggered by dysfunction in the immune system, which results in inflammation in various parts of the skin. There could be obvious symptoms, such as elevated plaques; these plaques may appear differently depending on the type of skin. This disease can cause inflammation in the elbows, lower back, scalp, knees, or other regions of the body. It can begin at any age, although it most commonly affects individuals between the ages of 50 and 60. Specific cells (such as T cells) have been observed to play an obvious role in the pathogenesis of psoriasis, in addition to specific immunological molecules such as TNF-, IL-12, IL-23, IL-17, and other molecules that can aid in the pathogenesis of psoriasis. So, during the past two decades, biologists have created chemical drugs that target these cells or molecules and therefore prevent the disease from occurring. Alefacept, efalizumab, Adalimumab, Ustekinumab, and Secukinumab are a few examples of chemical drugs. It was discovered that these chemical drugs have long-term side effects that can cause defects in the patient's body, such as the development of the rare but life-threatening disorder progressive multifocal leukoencephalopathy (PCL). Its rapidly progressive infection of the central nervous system caused by the JC virus and other drugs may cause increased production of neutralising anti-drug antibodies (ADA) and the risk of infusion reactions like pruritus, flushing, hypertension, headache, and rash. So, our context intends to talk in our review about natural products or plants that may have therapeutic characteristics for this disease and may have few or no side effects on the patient's body.

Evaluation of Branched-Chain Amino Acids in Children with Autism Spectrum Disorder and Epilepsy.

Autism spectrum disorder (ASD) and epilepsy run hand-to-hand in their pathophysiology. Epilepsy is not an uncommon finding in patients with ASD. The aim of the present study was to identify the metabolic abnormalities of BCAAs (leucine, isoleucine, and valine) in children with ASD with and without seizures in comparison with neurotypical controls. Also, this study aimed to investigate the presence of epileptiform discharges on electroencephalography (EEG) in ASD patients and to describe the types and frequency of seizures observed. The study included 90 children aged 2-7 years, 30 of whom were diagnosed with both ASD and epilepsy. The other 30 children were diagnosed as ASD without epilepsy, and a comparable 30 normally developed children served as a control group. The groups were matched by age and gender. All patients were referred to the Autism Disorders Clinic for interviews and examinations. The Childhood Autism Rating Scale (CARS) was applied to all study participants to assess the degree of autism. The present study results show that all types of seizures may be identified in ASD children. The median serum levels of BCAAs were lower in ASD children with and without epilepsy than in neurotypical controls. This opens the door for discussion about new etiologies and better categorizations of ASD based on genotype and genetic abnormalities detected. More studies with larger samples are needed to understand ASD better and to more reliable evaluate the association between ASD, EEG changes, seizures, and BCAAs.

Cardiopulmonary effects of prolonged surgical abdominal retractors application during general anesthesia: a prospective observational comparative study.

INTRODUCTION: Increasing abdominal pressures could affect pulmonary compliance and cardiac performance, a fact based on which the aim of the present study to detect the cardiopulmonary burden of multiple retractors application during supine versus lateral abdominal surgeries. We hypothesized that surgical ring multiple retractors application would affect the pulmonary and cardiac functions during both lateral and supine abdominal surgeries. METHODS: Prospective observational comparative study on forty surgical patients subdivided into two groups twenty each, comparing pulmonary compliance and cardiac performance before, during and after retractors application, group (S) supine position cystectomy surgery, and group (L) lateral position nephrectomy surgery under general anesthesia, Composite 1ry outcome; dynamic compliance C-dyn and cardiac index CI and Other outcome variables ICON cardio-meter were also recorded. RESULTS: C-dyn and C-stat were significantly decreased late during retractor application in lateral compared to supine surgery with significant decrease compared to basal values all over the surgical time. CI was significantly increased after retractor removal in both of the study groups compared to basal values. PAWP was significantly increased in -lateral compared to supine surgery -with significant increase compared to basal value all over the surgical time in both of the study groups. significant increase in DO2I compared to basal value during both supine and lateral positions. CONCLUSION: Surgical retraction results in a short-lived significant decreases in lung compliance and cardiac output particularly during the lateral-kidney position than the supine position compliance.

Assessment of dengue virus threat to blood safety and community health: A single center study in northern Egypt.

Background: The risk of transfusion transmitted dengue (DENV) is increasingly recognized and poses a risk to blood safety as well as spreading into non-immune communities. Objectives: To determine dengue serological profile, environmental risk, knowledge, and preventive measures among blood donors in a national blood bank in northern Egypt. Methods: A total of 500 blood donors were enrolled into this study between June and September 2018. Socio-demographic and medical data were collected using a predesigned questionnaire. Blood samples were screened for anti-DENV IgM, anti-DENV IgG and non-structural protein 1 antigen (DENV-NS1 antigen). Results: History of past dengue exposure was identified in 10.2% of blood donors. No samples (0.0%) tested positive for anti-DENV IgG, IgM or NS1 antigen. At the time of blood donation, no individuals had any symptoms suggestive of a dengue-related illness. Dengue exposure strongly correlated with travel to the Kingdom of Saudi Arabia (KSA), Sudan and the El-Quseir outbreak area in Egypt. Knowledge of dengue and prevention methods was found to be substantially deficient, and the relatively higher level of knowledge among exposed donors did not translate into appropriate preventative measures. Conclusions: Our risk assessment shows the impact of travel on DENV exposure and highlights its potential threat to disease spread in Egypt. Dengue awareness programs are urgently needed for effective prevention of transmission.

COVID-19 prophylaxis with doxycycline and zinc in health care workers: a prospective, randomized, double-blind clinical trial.

OBJECTIVES: This study aims to assess the efficacy of a combination treatment of doxycycline and zinc in the primary prevention of COVID-19 infection in Tunisian health care workers compared with two control groups. METHODS: We conducted a prospective, randomized, double-blind clinical trial over 5 months to determine the efficacy of a preventive combination treatment dose of doxycycline (100 mg/day) and zinc (15 mg/day), compared with a single-dose treatment with doxycycline versus placebo. The effectiveness of preventive treatment was measured by the significant decline in the number of cases of COVID-19 infection and/or a decrease in the viral load as determined by SARS-CoV-2 cycle threshold value using reverse transcription polymerase chain reaction tests. RESULTS: We detected a significant decrease of SARS-CoV-2 infection in the group that received both doxycycline and zinc compared with other participants. We also demonstrated that COVID-19 infection was neither associated with diabetes (P = 0.51) nor associated with hypertension (P = 0.99), asthma (P = 0.52), and chronic obstructive pulmonary disease (P = 0.27). CONCLUSION: Our findings indicated that preventive therapy reduced the risk of SARS-CoV-2. These results suggest that the combination of doxycycline and zinc has a protective effect in patients with SARS-CoV-2 infection.

Factors associated with dislocation after bipolar hemiarthroplasty through an (antero-)lateral approach in elderly patients with a femoral neck fracture: a retrospective cohort study with a nested case-control subanalysis of radiographic parameters.

INTRODUCTION: Dislocations of hip hemiarthroplasty (HHA) are serious complications. The aim of the study was to identify clinical aspects and radiographic parameters of the hip that put patients at risk for dislocation after HHA for femoral neck fractures. METHODS: This retrospective analysis included elderly patients with a femoral neck fracture treated with a HHA. A lateral (90.7%) and an anterolateral (9.3%) approach was applied. On pelvic radiographs, a nested-controlled analysis was performed. Two control patients were matched to one patient suffering a dislocation with respect to age, sex, and body-mass-index (BMI). RESULTS: In 527 HHA, 10 dislocations (1.9%) were identified. In the dislocation group (DG), all patients were female (100% vs. 73.5%, p = 0.071). No significant differences between the DG and the control group (CG) were found with respect to age, body-mass-index (BMI), ASA Score, routine laboratory parameters, and comorbidity. Radiographic analysis revealed a smaller center edge angle (CEA, 39.0, IQR 33.0-42.5 vs. 43.0, IQR 41.0-46.0, p = 0.013), a more varus neck-shaft angle (NSA, 130.0, IQR 125.8-133.5 vs. 135.0, IQR 134.0-137.0, p = 0.011) of the contralateral side and a higher femoral head extrusion index (FHEI) in the DG (FHEI, 11.5, IQR 9.8-16.3 vs. 2.0 IQR 0.0-9.0, p = 0.003). In addition, a greater trochanteric fracture was associated with an increased likelihood for HHA dislocations (30.0% vs 6.0%, p = 0.022). CONCLUSION: A smaller radiographic center edge angle, a more varus neck-shaft angle of the contralateral side, a higher femoral head extrusion index and intraoperative fractures of the greater trochanter are associated with an increased risk of HHA dislocation.

Foam Synthesis of Nickel/Nickel (II) Hydroxide Nanoflakes Using Double Templates of Surfactant Liquid Crystal and Hydrogen Bubbles: A High-Performance Catalyst for Methanol Electrooxidation in Alkaline Solution.

This work demonstrates the chemical synthesis of two-dimensional nanoflakes of mesoporous nickel/nickel (II) hydroxide (Ni/Ni(OH)2-NFs) using double templates of surfactant self-assembled thin-film and foam of hydrogen bubbles produced by sodium borohydride reducing agent. Physicochemical characterizations show the formation of amorphous mesoporous 2D nanoflakes with a Ni/Ni(OH)2 structure and a high specific surface area (165 m2/g). Electrochemical studies show that the electrocatalytic activity of Ni/Ni(OH)2 nanoflakes towards methanol oxidation in alkaline solution is significantly enhanced in comparison with that of parent bare-Ni(OH)2 deposited from surfactant-free solution. Cyclic voltammetry shows that the methanol oxidation mass activity of Ni/Ni(OH)2-NFs reaches 545 A/cm2 gcat at 0.6 V vs. Ag/AgCl, which is more than five times higher than that of bare-Ni(OH)2. Moreover, Ni/Ni(OH)2-NFs reveal less charge transfer resistance (10.4 Ω), stable oxidation current density (625 A/cm2 gcat at 0.7 V vs. Ag/AgCl), and resistance to the adsorption of reaction intermediates and products during three hours of constant-potential methanol oxidation electrolysis in alkaline solution. The high-performance electrocatalytic activity of Ni/Ni(OH)2 nanoflakes is mainly derived from efficient charge transfer due to the high specific surface area of the 2D mesoporous architecture of the nanoflakes, as well as the mass transport of methanol to Ni2+/Ni3+ active sites throughout the catalyst layer.

Risk factors for intraoperative greater trochanteric fractures in hemiarthroplasty for intracapsular femoral neck fractures.

PURPOSE: Hemiarthroplasty is widely accepted as the treatment of choice in elderly patients with a displaced intracapsular femoral neck fracture. Intraoperative greater trochanteric fractures thwart this successful procedure, resulting in prolonged recovery, inferior outcome, and increased risk of revision surgery. Hence, this study analyzed factors potentially associated with an increased risk for intraoperative greater trochanteric fracture. METHODS: This retrospective study included 512 hemiarthroplasties in 496 patients with a geriatric intracapsular femoral neck fracture from July 2010 to March 2020. All patients received the same implant type of which 90.4% were cemented and 9.6% non-cemented. Intra- and postoperative radiographs and reports were reviewed and particularly screened for greater trochanteric fractures. RESULTS: Female patients accounted for 74% and mean age of the patients was 82.3 (± 8.7) years. 34 (6.6%) intraoperative greater trochanteric fractures were identified. In relation to patient-specific factors, only a shorter prothrombin time was found to be significantly associated with increased risk of intraoperative greater trochanteric fracture (median 96%, IQR 82-106% vs. median 86.5%, IQR 68.8-101.5%; p = 0.046). Other factors associated with greater trochanteric fracture were a shorter preoperative waiting time and changes in perioperative settings. Outcome of patients with greater trochanteric fracture was worse with significantly more surgical site infection requiring revision surgery (17.6% vs. 4.2%, p = 0.005). CONCLUSION: Prolonged prothrombin time, a shorter preoperative waiting time, and implementing new procedural standards and surgeons may be associated with an increased risk of a greater trochanteric fracture. Addressing these risk factors may reduce early periprosthetic infection which is strongly related to greater trochanteric fractures.

Management of Modular Mega-Implant Infection of the Lower Extremity.

INTRODUCTION: Revision arthroplasty involving mega-implants is associated with a high complication rate. In particular, infection is a serious complication of revision arthroplasty of hip and knee joints and has been reported to have an average rate of 18%, and for mega-implants, the range is from 3 to 36%. This study was designed to analyze the strategy of treatment of infection of mega-endoprostheses of the lower extremities in our patient cohort, particularly the management of chronic infection. MATERIAL AND METHODS: This was a retrospective study that focused on the results of the treatment of periprosthetic infections of mega-implants of the lower extremities. We identified 26 cases with periprosthetic infections out of 212 patients with 220 modular mega-endoprostheses of the lower extremities who were treated in our department between September 2013 and September 2019. As a reinfection or recurrence, we defined clinical and microbiological recurrences of local periprosthetic joint infections after an antibiotic-free period. RESULTS: In this study, 200 cases out of 220 were investigated. The average follow-up period was approximately 18 months (6 months to 6 years). Endoprosthesis infections after implantation of mega-implants occurred in 26 cases (13%). This group comprised 2 early infections (within the first 4 weeks) and 24 chronic infections (between 10 weeks and 6 years after implantation). Nineteen cases out of the identified 26 cases with infection (73.1%) belong to the group of patients who were operated on due to major bone loss following explantation of endoprosthetic components due to previous periprosthetic joint infection. The remaining seven cases with infection comprised four cases following management of periprosthetic fracture, two cases following treatment of aseptic loosening, and one case following tumor resection. All infections were treated surgically. In all cases, the duration of continuous antibiotic treatment did not exceed 6 weeks. Both cases with early infection were treated by exchanging polyethylene inlays and performing debridement with lavage (two cases). In two (7.7%) cases with chronic infection, one-stage surgery was performed. In all remaining cases with chronic infection (22 cases; 84.6%), explantation of all components and temporary implantation of cement spacers were carried out prior to reimplantation. CONCLUSION: There is still no gold standard therapeutic regimen for the management of periprosthetic infection of mega-implants, though radical surgical debridement and lavage accompanied by systemic antibiotic therapy are the most important therapeutic tools in all cases of periprosthetic infections, regardless of the time of onset. Further studies are needed to standardize management strategies of such infections. Nevertheless, it is not uncommon for compromises to be made based on the particular condition of the individual.

Evaluation of symmetric dimethylarginine and Doppler ultrasonography in the diagnosis of gentamicin-induced acute kidney injury in dogs.

Acute kidney injury is a common problem in dogs and is associated with significant morbidity and mortality. So, the present study aimed to evaluate symmetric dimethylarginine (SDMA) and Doppler ultrasonography including resistive index (RI) in the diagnosis of acute kidney injury in dogs. Ten healthy mongrel dogs were injected with gentamicin sulfate 10% at the dose of 30 mg/kg body weight daily for 10 days for induction of acute kidney injury. Clinical, biochemical, ultrasonographic, and Doppler ultrasonographic examinations and urinalysis were performed for all dogs on 0 day before induction, on the 5th day, and on the 10th day of induction. The results of the current study showed significant increase in plasma level of SDMA, serum urea, creatinine, phosphorus, and potassium and a significant decrease in serum sodium, calcium, and chloride on the 5th day and 10th day of induction, and there was an increase in renal cortical echogenicity of the right and left kidney compared to adjacent liver and spleen, respectively. RI value showed a significant increase on the 5th day and 10th day of induction. The present study showed that SDMA is a sensitive and promising biomarker for diagnosis of acute kidney injury in dogs compared to routine biomarkers; also, the RI of Doppler ultrasonography is useful for early identifying acute kidney injury when the only observable change is an increase in cortical echogenicity.