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Markus Pääkkönen1,2 1Department of Pediatric Orthopaedic Surgery, 2Department of Hand Surgery, Turku University Hospital and the University of Turku, Turku, Finland Abstract: Acute septic arthritis in children is usually hematogenous. It is more common in boys, and it most often affects the large joints of the lower limb. Diagnosis is based on cultures obtained from the infected joint and is supported by C-reactive protein blood test or ultrasound imaging. Staphylococcus aureus is the most common causative agent and is the primary target for empiric treatment. First-generation cephalosporins and clindamycin are suitable antibiotics. Vancomycin is utilized in areas with high rates of clindamycin- and methicillin-resistant S. aureus. After a short intravenous administration of 2–4 days, a total course of 2 weeks is sufficient in uncomplicated cases. Early antibiotic treatment has significantly improved the prognosis in high-income settings, but uncomplicated recovery is compromised if the treatment is delayed. Complications such as symptomatic osteoarthritis or avascular necrosis of the femoral head develop slowly. A long follow-up of 1–2 years is required to detect all possible sequelae. Keywords: child, septic arthritis, sepsis, Staphylococcus aureus

The enzyme levels of muscle energy metabolism were studied in eight male meniscectomy patients before and 10 minutes after release of the tourniquet and on the third post-operative day. The average tourniquet time was 65.1 min. The muscle samples were taken from the vastus lateralis muscles; the healthy side served as the control. The greatest enzyme changes 10 min after release of the tourniquet were the falls in succinate dehydrogenase (SDH) and creatine phosphokinase (CPK) activities, (p less than 0.01 and p less than 0.025 respectively). On the 3rd day phosphofructokinase (FFK) and malate dehydrokinase (MDH) activities were also lowered in the tourniquet limb, but the lactate dehydrogenase (LDH) was not changed significantly. In the control extremity only SDH showed a lowered value on the 3rd post-operative day (p less than 0.05), perhaps due to hypokinesia in hospital. The results indicate that even one-hour tourniquet ischaemia causes an enzyme release from muscle and for at least three days after the tourniquet enzyme activities in muscle are lowered, perhaps because of the combined effect of the tourniquet ischaemia and hypokinesia after the operation. [ABSTRACT FROM AUTHOR]

Somatostatin (ST) and vasopressin (VP) infusions were compared in the treatment of actively bleeding esophageal varices. Fifty-four patients with liver cirrhosis were included in the study. Thirty-two were given ST 4.2 µg/min, and 22 patients were given VP 0.4 IU/ min for 72 h after endoscopic diagnosis. The role of alcoholic cirrhosis was similar in both groups. Initial control of bleeding was achieved significantly more often (p = 0.0281) when ST was used (84.4%) than during VP treatment (57.1%). Rebleeding occurred in 18.8% and 4.8%, respectively. Side effects of treatment were significantly more common when VP was used than during ST treatment (p = 0.0021). Overall mortality was high in both groups, being 34% in the ST group and 36% in the VP group. ST infusion seems to be more effective and safer than VP in the treatment of acute variceal bleeding. However, the high frequency of rebleeding during ST treatment means that, after primary hemostasis with ST infusion, other methods, such as surgery or sclerotherapy, are needed to prevent the serious complications of rebleeding. [ABSTRACT FROM AUTHOR]

Background: Foxn1 -/- deficient mice are a rare model of regenerative skin wound healing among mammals. In wounded skin, the transcription factor Foxn1 interacting with hypoxia-regulated factors affects re-epithelialization, epithelial-mesenchymal transition (EMT) and dermal white adipose tissue (dWAT) reestablishment and is thus a factor regulating scar-forming/reparative healing. Here, we hypothesized that transcriptional crosstalk between Foxn1 and Hif-1α controls the switch from scarless (regenerative) to scar-present (reparative) skin wound healing. To verify this hypothesis, we examined (i) the effect of hypoxia/normoxia and Foxn1 signalling on the proteomic signature of Foxn1 -/- (regenerative) dermal fibroblasts (DFs) and then (ii) explored the effect of Hif-1α or Foxn1/Hif-1α introduced by a lentiviral (LV) delivery vector to injured skin of regenerative Foxn1 -/- mice with particular attention to the remodelling phase of healing., Results: We showed that hypoxic conditions and Foxn1 stimulation modified the proteome of Foxn1 -/- DFs. Hypoxic conditions upregulated DF protein profiles, particularly those related to extracellular matrix (ECM) composition: plasminogen activator inhibitor-1 (Pai-1), Sdc4, Plod2, Plod1, Lox, Loxl2, Itga2, Vldlr, Ftl1, Vegfa, Hmox1, Fth1, and F3. We found that Pai-1 was stimulated by hypoxic conditions in regenerative Foxn1 -/- DFs but was released by DFs to the culture media exclusively upon hypoxia and Foxn1 stimulation. We also found higher levels of Pai-1 protein in DFs isolated from Foxn1 +/+ mice (reparative/scar-forming) than in DFs isolated from Foxn1 -/- (regenerative/scarless) mice and triggered by injury increase in Foxn1 and Pai-1 protein in the skin of mice with active Foxn1 (Foxn1 +/+ mice). Then, we demonstrated that the introduction of Foxn1 and Hif-1α via lentiviral injection into the wounded skin of regenerative Foxn1 -/- mice activates reparative/scar-forming healing by increasing the wounded skin area and decreasing hyaluronic acid deposition and the collagen type III to I ratio. We also identified a stimulatory effect of LV-Foxn1 + LV-Hif-1α injection in the wounded skin of Foxn1 -/- mice on Pai-1 protein levels., Conclusions: The present data highlight the effect of hypoxia and Foxn1 on the protein profile and functionality of regenerative Foxn1 -/- DFs and demonstrate that the introduction of Foxn1 and Hif-1α into the wounded skin of regenerative Foxn1 -/- mice activates reparative/scar-forming healing., (© 2024. The Author(s).)

Purpose: Preoperative antibiotic prophylaxis is associated to internal fixation for closed phalangeal and metacarpal fracture, but its effectiveness is not known., Methods: In a consecutive series of 119 adult patients undergoing Kirschner-wire fixation for phalangeal or metacarpal fracture, 56.3% (n = 67) received antibiotic prophylaxis and 43.7% (n = 52) did not., Results: The rate of deep surgical site infection was 1.5% (n = 1) in the group with antibiotic prophylaxis and 1.9% (n = 1) in the group without. Minor skin irritation or infection of the pin tract occurred in 13.4% of cases (n = 9) in the group with antibiotic prophylaxis and 9.6% (n = 5) in the group without., Conclusion: Our findings suggest that use of antibiotic prophylaxis could be reduced in the treatment of closed fractures of the hand treated with removable pins., Type of Study/level of Evidence: Therapeutic IV (retrospective review)., (Copyright © 2024 SFCM. Published by Elsevier Masson SAS. All rights reserved.)

Background: Surgery, needle fasciotomy, and collagenase injection are used to treat Dupuytren contracture. The treatment decision requires balancing initial morbidity and costs of surgery against its potential long-term benefits over needle fasciotomy and collagenase., Objective: To compare the effectiveness of surgery, needle fasciotomy, and collagenase injection at 3 months and 2 years (secondary time points of the trial)., Design: A multicenter, randomized, outcome assessor-blinded, superiority trial. (ClinicalTrials.gov: NCT03192020)., Setting: 6 public hospitals in Finland., Participants: 302 persons with treatment-naive Dupuytren contracture (contracture angle <135°)., Intervention: Surgery ( n  = 101), needle fasciotomy ( n  = 101), or collagenase ( n  = 100)., Measurements: The primary outcome was the success rate, defined as greater than 50% contracture release and patients reaching the patient acceptable symptom state. Secondary outcomes included hand function, pain, quality of life, patient satisfaction, residual contracture angle, finger flexion, risk for retreatment, and serious adverse events., Results: A total of 292 (97%) and 284 (94%) participants completed the 3-month and 2-year follow-ups. Success rates were similar at 3 months: 71% (95% CI, 62% to 80%) for surgery, 73% (CI, 64% to 82%) for needle fasciotomy, and 73% (CI, 64% to 82%) for collagenase. At 2 years, surgery had superior success rates compared with both needle fasciotomy (78% vs. 50%; adjusted risk difference [aRD], 0.30 [CI, 0.17 to 0.43]) and collagenase (78% vs. 65%; aRD, 0.13 [CI, 0.01 to 0.26]). Secondary analyses paralleled with the primary analysis., Limitation: Participants were not blinded., Conclusion: Initial outcomes are similar between the treatments, but at 2 years success rates were maintained in the surgery group but were lower with both needle fasciotomy and collagenase despite retreatments., Primary Funding Source: Research Council of Finland., Competing Interests: Disclosures: Disclosures can be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M23-1485.

Competing Interests: The author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request.

Background: Carpal tunnel syndrome (CTS) is a compression neuropathy of the median nerve at the wrist. Surgery is considered when symptoms persist despite the use of non-surgical treatments. It is unclear whether surgery produces a better outcome than non-surgical therapy. This is an update of a Cochrane review published in 2008., Objectives: To assess the evidence regarding the benefits and harms of carpal tunnel release compared with non-surgical treatment in the short (< 3 months) and long (> 3 months) term., Search Methods: In this update, we included studies from the previous version of this review and searched the Cochrane Neuromuscular Specialised Register, CENTRAL, Embase, MEDLINE, ClinicalTrials.gov and WHO ICTRP until 18 November 2022. We also checked the reference lists of included studies and relevant systematic reviews for studies., Selection Criteria: We included randomised controlled trials comparing any surgical technique with any non-surgical therapies for CTS., Data Collection and Analysis: We used the standard methodological procedures expected by Cochrane., Main Results: The 14 included studies randomised 1231 participants (1293 wrists). Eighty-four per cent of participants were women. The mean age ranged from 32 to 53 years, and the mean duration of symptoms from 31 weeks to 3.5 years. Trial sizes varied from 22 to 176 participants. The studies compared surgery with: splinting, corticosteroid injection, splinting and corticosteroid injection, platelet-rich plasma injection, manual therapy, multimodal non-operative treatment, unspecified medical treatment and hand support, and surgery and corticosteroid injection with corticosteroid injection alone. Since surgery is generally used for its long-term effects, this abstract presents only long-term results for surgery versus splinting and surgery versus corticosteroid injection. 1) Surgery compared to splinting in the long term (> 3 months) Surgery probably results in a higher rate of clinical improvement (risk ratio (RR) 2.10, 95% confidence interval (CI) 1.04 to 4.24; 3 studies, 210 participants; moderate-certainty evidence). Surgery probably does not provide clinically important benefit in symptoms or hand function compared with splinting (moderate-certainty evidence). The mean Boston Carpal Tunnel Questionnaire (BCTQ) Symptom Severity Scale (scale 1 to 5; higher is worse; minimal clinically important difference (MCID) = 1) was 1.54 with splint and 0.26 points better with surgery (95% CI 0.52 better to 0.01 worse; 2 studies, 195 participants). The mean BCTQ Functional Status Scale (scale 1 to 5; higher is worse; MCID 0.7) was 1.75 with splint and 0.36 points better with surgery (95% CI 0.62 better to 0.09 better; 2 studies, 195 participants). None of the studies reported pain. Surgery may not provide better health-related quality of life compared with splinting (low-certainty evidence). The mean EQ-5D index (scale 0 to 1; higher is better; MCID 0.074) was 0.81 with splinting and 0.04 points better with surgery (95% CI 0.0 to 0.08 better; 1 study, 167 participants). We are uncertain about the risk of adverse effects (very low-certainty evidence). Adverse effects were reported amongst 60 of 98 participants (61%) in the surgery group and 46 of 112 participants (41%) in the splinting group (RR 2.11, 95% CI 0.37 to 12.12; 2 studies, 210 participants). Surgery probably reduces the risk of further surgery; 41 of 93 participants (44%) were referred to surgery in the splinting group and 0 of 83 participants (0%) repeated surgery in the surgery group (RR 0.03, 95% CI 0.00 to 0.21; 2 studies, 176 participants). This corresponds to a number needed to treat for an additional beneficial outcome (NNTB) of 2 (95% CI 1 to 9). 2) Surgery compared to corticosteroid injection in the long term (> 3 months) We are uncertain if clinical improvement or symptom relief differs between surgery and corticosteroid injection (very low-certainty evidence). The RR for clinical improvement was 1.23 (95% CI 0.73 to 2.06; 3 studies, 187 participants). For symptoms, the standardised mean difference (SMD) was -0.60 (95% CI -1.88 to 0.69; 2 studies, 118 participants). This translates to 0.4 points better (95% CI from 1.3 better to 0.5 worse) on the BCTQ Symptom Severity Scale. Hand function or pain probably do not differ between surgery and corticosteroid injection (moderate-certainty evidence). For function, the SMD was -0.12 (95% CI -0.80 to 0.56; 2 studies, 191 participants) translating to 0.10 points better (95% CI 0.66 better to 0.46 worse) on the BCTQ Functional Status Scale with surgery. Pain (0 to 100 scale) was 8 points with corticosteroid injection and 6 points better (95% CI 10.45 better to 1.55 better; 1 study, 123 participants) with surgery. We found no data to estimate the difference in health-related quality of life (very low-certainty evidence). We are uncertain about the risk of adverse effects and further surgery (very low-certainty evidence). Adverse effects were reported amongst 3 of 45 participants (7%) in the surgery group and 2 of 45 participants (4%) in the corticosteroid injection group (RR 1.49, 95% CI 0.25 to 8.70; 2 studies, 90 participants). In one study, 12 of 83 participants (15%) needed surgery in the corticosteroid group, and 7 of 80 participants (9%) needed repeated surgery in the surgery group (RR 0.61, 95% CI 0.25 to 1.46; 1 study, 163 participants)., Authors' Conclusions: Currently, the efficacy of surgery in people with CTS is unclear. It is also unclear if the results can be applied to people who are not satisfied after trying various non-surgical options. Future studies should preferably blind participants from treatment allocation and randomise people who are dissatisfied after being treated non-surgically. The decision for a patient to opt for surgery should balance the small benefits and potential risks of surgery. Patients with severe symptoms, a high preference for clinical improvement and reluctance to adhere to non-surgical options, and who do not consider potential surgical risks and morbidity a burden, may choose surgery. On the other hand, those who have tolerable symptoms, who have not tried non-surgical options and who want to avoid surgery-related morbidity can start with non-surgical options and have surgery only if necessary. We are uncertain if the risk of adverse effects differs between surgery and non-surgical treatments. The severity of adverse effects may also be different., (Copyright © 2024 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

Background: Arthroscopic scaphotrapeziotrapezoid (STT) fusion (ASTTF) has emerged in the recent decade as an option for traditional open surgery. This retrospective study describes our technique and results of ASTTF. Methods: Medical records and radiological data of patient who had undergone ASTTF between 2014 and 2022 in two tertiary hospitals were reviewed. Results: Five ASTTF in four patients were identified. The mean age of the patients were 52.4 years. Fusion was achieved in four out of five wrists (80%). The mean postoperative radio-scaphoid angle was 48°, grip 32 kg (70% compared to contralateral hand), extension 54° (86%) and flexion 46° (93%). The mean follow-up time was 18 months (range 5 months to 4 years). One wrist (20%) developed STT non-union requiring a reoperation 2 years after index surgery. Conclusions: ASTTF is a technically challenging procedure with a long learning curve and surgery time. However, ASTTF is less invasive compared to the open procedure and our results were like the open procedures described in literature. Further studies are needed to compare the benefits and results of open and ASTTF in a prospective and randomised setup. Level of Evidence: Level IV (Therapeutic).

Mitochondrial glycolysis and hyperactivity of the phosphatidylinositol 3-kinase-protein kinase B (AKT) pathway are hallmarks of malignant brain tumors. However, kinase inhibitors targeting AKT (AKTi) or the glycolysis master regulator pyruvate dehydrogenase kinase (PDKi) have failed to provide clinical benefits for brain tumor patients. Here, we demonstrate that heterogeneous glioblastoma (GB) and medulloblastoma (MB) cell lines display only cytostatic responses to combined AKT and PDK targeting. Biochemically, the combined AKT and PDK inhibition resulted in the shutdown of both target pathways and priming to mitochondrial apoptosis but failed to induce apoptosis. In contrast, all tested brain tumor cell models were sensitive to a triplet therapy, in which AKT and PDK inhibition was combined with the pharmacological reactivation of protein phosphatase 2A (PP2A) by NZ-8-061 (also known as DT-061), DBK-1154, and DBK-1160. We also provide proof-of-principle evidence for in vivo efficacy in the intracranial GB and MB models by the brain-penetrant triplet therapy (AKTi + PDKi + PP2A reactivator). Mechanistically, PP2A reactivation converted the cytostatic AKTi + PDKi response to cytotoxic apoptosis, through PP2A-elicited shutdown of compensatory mitochondrial oxidative phosphorylation and by increased proton leakage. These results encourage the development of triple-strike strategies targeting mitochondrial metabolism to overcome therapy tolerance in brain tumors., (© 2023 The Authors. Molecular Oncology published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

This clinical guideline is intended for use by orthopedic surgeons and physicians who care for patients with possible or documented septic arthritis of a native joint (SANJO). It includes evidence and opinion-based recommendations for the diagnosis and management of patients with SANJO., Competing Interests: At least one of the (co-)authors is a member of the editorial board of ., (Copyright: © 2023 Christen Ravn et al.)

Semiconstrained arthroplasty of the distal radioulnar joint (DRUJ) (Scheker prosthesis, Aptis Medical, Glenview, KY, USA) is a treatment option in case of irreparable destruction of the DRUJ. In our unit, a Scheker endoprosthesis was implanted in 5 wrists in 4 patients. 3/5 wrists (60%) in 3/4 patients (75%) underwent revision surgery. Reasons for revision surgery were implant loosening, periprosthetic fracture of the radius and suspicion of periprosthetic infection. Asymptomatic loosening of the screw of the radial head cover was detected in one wrist. Scheker arthroplasty is technically demanding. The prosthesis is prone to failure over the long term. Before implantation, all patients should be informed of the high risk of revision surgery., (Copyright © 2022 SFCM. Published by Elsevier Masson SAS. All rights reserved.)

Skin exposed to environmental threats, including injuries and oxidative stress, develops an efficient but not fully recognized system of repair and antioxidant protection. Here, using mass spectrometry analysis (LC-MS/MS), followed by in vitro and in vivo experiments, we provided evidence that Foxn1 in keratinocytes regulates elements of the electron transport chain and participates in the thioredoxin system (Txn2, Txnrd3, and Srxn1) induction, particularly in a hypoxic environment. We first showed that Foxn1 in keratinocytes upregulates glutathione thioredoxin reductase 3 (Txnrd3) protein expression, and high levels of Txnrd3 mRNA were detected in injured skin of Foxn1 +/+ mice. We also showed that Foxn1 strongly downregulated the Ccn2 protein expression, participating in epidermal reconstruction after injury. An in vitro assay revealed that Foxn1 controls keratinocyte migration, stimulating it under normoxia and suppressing it under hypoxia. Keratinocytes overexpressing Foxn1 and exposed to hypoxia displayed a reduced ability to promote angiogenesis by downregulating Vegfa expression. In conclusion, this study showed a new mechanism in which Foxn1, along with hypoxia, participates in the activation of antioxidant defense and controls the functional properties of keratinocytes., (© 2022 The Authors. The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

Although most malunions after pediatric distal radius fractures will remodel as the child grows, adolescent patients with severe malunion and limited growth require reduction to restore alignment. The authors technique for a mini-invasive osteotomy is presented. The apex of the malunion is approached from a single 2 cm volar incision through the flexor carpi radialis sheath. Open wedge osteotomy is performed. The osteosynthesis is secured with an individually contoured T-plate. The procedure was used to correct a severe visible malunion in a 12-year-old girl. Normal alignment was achieved with no nerve or tendon injury or irritation, infection, refracture, or any other complication. Mini-invasive osteotomy with a volar plate is a feasible method for experienced hand surgeons for the treatment of distal radius malunion in adolescents., Competing Interests: Conflicts of Interest and Source of Funding: The authors report no conflicts of interest and no source of funding., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

A Galeazzi-equivalent lesion occurs in children and adolescents following a traumatic distal radius fracture when the strong radioulnar ligaments and relative weakness of the ulnar physis result in an avulsion-type Salter-Harris III fracture of the distal ulna. In unreduced fractures, the osteogenic nature of the torn periosteal sleeve may result in the formation of a bifid distal ulna. We describe two cases of bifid distal ulna that developed after missed Galeazzi-equivalent lesions. The first case was treated with resection of the volar limb and reduction of the ulnar fracture, whereas the second case was treated with simple resection of the dorsal limb. Negative ulnar variance developed in both cases. Level of Evidence: Level V (Case report).

Competing Interests: The author certifies that neither he, nor any members of his immediate family, have funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research® editors and board members are on file with the publication and can be viewed on request.

Context: Mitochondria are essential for cellular energy homeostasis, yet their role in subcutaneous adipose tissue (SAT) during different types of weight-loss interventions remains unknown., Objective: To investigate how SAT mitochondria change following diet-induced and bariatric surgery-induced weight-loss interventions in 4 independent weight-loss studies., Methods: The DiOGenes study is a European multicenter dietary intervention with an 8-week low caloric diet (LCD; 800 kcal/d; n = 261) and 6-month weight-maintenance (n = 121) period. The Kuopio Obesity Surgery study (KOBS) is a Roux-en-Y gastric bypass (RYGB) surgery study (n = 172) with a 1-year follow-up. We associated weight-loss percentage with global and 2210 mitochondria-related RNA transcripts in linear regression analysis adjusted for age and sex. We repeated these analyses in 2 studies. The Finnish CRYO study has a 6-week LCD (800-1000 kcal/d; n = 19) and a 10.5-month follow-up. The Swedish DEOSH study is a RYGB surgery study with a 2-year (n = 49) and 5-year (n = 37) follow-up., Results: Diet-induced weight loss led to a significant transcriptional downregulation of oxidative phosphorylation (DiOGenes; ingenuity pathway analysis [IPA] z-scores: -8.7 following LCD, -4.4 following weight maintenance; CRYO: IPA z-score: -5.6, all P < 0.001), while upregulation followed surgery-induced weight loss (KOBS: IPA z-score: 1.8, P < 0.001; in DEOSH: IPA z-scores: 4.0 following 2 years, 0.0 following 5 years). We confirmed an upregulated oxidative phosphorylation at the proteomics level following surgery (IPA z-score: 3.2, P < 0.001)., Conclusions: Differentially regulated SAT mitochondria-related gene expressions suggest qualitative alterations between weight-loss interventions, providing insights into the potential molecular mechanistic targets for weight-loss success., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.)

In the Baltic Sea, water is stratified due to differences in density and salinity. The stratification prevents water from mixing, which could affect sinking rates of microplastics in the sea. We studied the accumulation of microplastics to halocline and thermocline. We sampled water with a 100 μm plankton net from vertical transects between halo- and thermocline, and a 30 L water sampler from the end of halocline and the beginning of thermocline. Thereafter, microplastics in the whole sample volumes were analyzed with imaging Fourier transform infrared spectroscopy (FTIR). The plankton net results showed that water column between halo- and thermoclines contained on average 0.92 ± 0.61 MP m -3 (237 ± 277 ng/m -3 ; mean ± SD), whereas the 30 L samples from the end of halocline and the beginning of thermocline contained 0.44 ± 0.52 MP L -1 (106 ± 209 ng L -1 ). Hence, microplastics are likely to accumulate to thin layers in the halocline and thermocline. The vast majority of the found microplastics were polyethylene, polypropylene and polyethylene terephthalate, which are common plastic types. We did not observe any trend between the density of microplastics and the sampling depth, probably because biofilm formation affected the sinking rates of the particles. Our results indicate the need to sample deeper water layers in addition to surface waters at least in the stratified water bodies to obtain a comprehensive overview of the abundance of microplastics in the aquatic environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Cobra snakes, including Naja mossambica and Naja nigricincta nigricincta, are one of the major groups of snakes responsible for snakebites in southern Africa, producing significant cytotoxicity and tissue damage. The venom of N. mossambica has been briefly characterised, but that of N. n. nigricincta is not reported. The current study identifies the venom proteins of N. mossambica and N. n. nigricincta . This is achieved using sodium dodecyl sulphate (SDS)-polyacrylamide gel eletrophroresis (PAGE), followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Most of the proteins were less than 17 kDa in both snakes. N. mossambica was found to have 75 proteins in total (from 16 protein families), whereas N.n. nigricincta had 73 (from 16 protein families). Of these identified proteins, 57 were common in both snakes. The proteins identified belonged to various families, including the three-finger toxins (3FTx), Cysteine-rich secretory proteins (CRiSP), Phospholipase A2 (PLA 2 ) and Venom metalloproteinase M12B (SVMP). The current study contributes to the profile knowledge of snake venom compositions, which is of fundamental value in understanding the proteins that play a major role in envenomation.