Effects of maleimide-polyethylene glycol-modified human hemoglobin (MP4) on tissue necrosis in SKH1-hr hairless mice

<p>Abstract</p> <p>Objective</p> <p>Tissue hypoxia after blood loss, replantation and flap reperfusion remains a challenging task in surgery. Normovolemic hemodilution improves hemorheologic properties without increasing oxygen carrying capacity. Red blood cell transfusion is the current standard of treatment with its attendant risks. The aim of this study was to investigate the potential of the chemically modified hemoglobin, MP4, to reduce skin flap necrosis and its effect on selected blood markers and kidneys.</p> <p>Materials and methods</p> <p>Tissue ischemia was induced in the ear of hairless mice (n = 26). Hemodilution was performed by replacing one third of blood volume with the similar amount of MP4, dextran, or blood. The extent of non-perfused tissue was assessed by intravital fluorescent microscopy.</p> <p>Results</p> <p>Of all groups, MP4 showed the smallest area of no perfusion (in percentage of the ear ± SEM: 16.3% ± 2.4), the control group the largest (22.4% ± 3.5). Leukocytes showed a significant increase in the MP4 and dextran group (from 8.7 to 13.6 respectively 15.4*10⁹/l). On histology no changes of the kidneys could be observed.</p> <p>Conclusion</p> <p>MP4 causes an increase of leukocytes, improves the oxygen supply of the tissue and shows no evidence of renal impairment.</p

A Qualitative and Quantitative Analysis of Protein Substitution in Human Burn Wounds

Objective: In major burn wounds of more than 15% total burn surface area mediator-associated reactions lead to capillary leak resulting in critical condition. Little is known about the efficiency of protein substitution. We quantified and qualified the systemic and local protein loss in burn patients during protein substitution, comparing fresh frozen plasma and the human serum protein solution Biseko. Methods: In 40 patients suffering from second-degree burn wounds with the total burn surface area between 20% and 60%, immediately after admission a defined wound surface area was enclosed with in a wound chamber. Wound fluid and serum samples were collected in 8 hour intervals for 2 days. Samples were analyzed for total protein, albumin, immunoglobulins -A, -G, -M, clotting parameters, c-reactive protein, and white blood cells. Protein substitution started 24 hour posttrauma. In a randomized pattern, patients received equal volumes of fresh frozen plasma or Biseko. Results: Total protein and albumin accumulated in high concentrations in wound fluid. With beginning of fresh frozen plasma substitution on day 2 posttrauma, serum total protein (1.7 g–3.9 g) and albumin (1.3 g–3.4 g) concentrations increased. Substitution of Biseko resulted in a stronger increase (serum total protein 1.8 g to 4.5 g, albumin 0.9 g to 3.4 g). Wound fluid concentrations revealed similar change patterns. Immunoglobulins showed higher serum levels in the Biseko group. C-reactive protein and white blood cell values indicated a lower immunological reaction in the Biseko group. Conclusions: Substitution of human protein solutions such as Biseko can result in significantly higher serum protein and albumin concentrations as well as lower infection parameters. Higher serum immunoglobulins could help to decrease potential immunodeficiency

Annexin A2 mediates apical trafficking of renal Na(+)-K(+)-2Cl(-)-cotransporter

The furosemide-sensitive Na(+)-K(+)-2Cl(-)-cotransporter (NKCC2) is responsible for urine concentration, and helps maintain systemic salt homeostasis. Its activity depends on trafficking to, and insertion into, the apical membrane, as well as on phosphorylation of conserved N-terminal serine and threonine residues. Vasopressin (AVP), signaling via PKA and other kinases, activates NKCC2. Association of NKCC2 with lipid rafts facilitates its AVP-induced apical translocation and activation at the surface. Lipid raft microdomains typically serve as platforms for membrane proteins to facilitate their interactions with other proteins, but little is known about partners that interact with NKCC2. Yeast two-hybrid screening identified an interaction between NKCC2 and the cytosolic protein, annexin A2 (AnxA2). Annexins mediate lipid raft-dependent trafficking of transmembrane proteins, including the AVP-regulated water channel, aquaporin 2. Here, we demonstrate that AnxA2, which binds to phospholipids in a Ca(2+)-dependent manner and may organize microdomains, is co-distributed with NKCC2 to promote its apical translocation in response to AVP stimulation and low chloride hypotonic stress. NKCC2 and AnxA2 interact in a phosphorylation-dependent manner. Phosphomimetic AnxA2 carrying a mutant, Src-dependent phosphoacceptor (AnxA2-Y24D-GFP), enhanced surface expression and raft association of NKCC2 by 5-fold upon AVP stimulation, whereas PKC-dependent AnxA2-S26D-GFP did not. As the AnxA2 effect involved only non-phosphorylated NKCC2, it appears to affect NKCC2 trafficking. Overexpression or knockdown experiments further supported the role of AnxA2 in the apical translocation and surface expression of NKCC2. In summary, this study identifies AnxA2 as a lipid raft-associated trafficking factor for NKCC2 and provides mechanistic insight into the regulation of this essential cotransporter

Union rate and clinical outcomes of second-try scaphoid reconstructions after failed primary scaphoid osteosynthesis or reconstruction. A retrospective, single-center cohort study of 52 patients

IntroductionScaphoid non-union after failed primary surgery presents significant therapeutic challenges.MethodsIn this retrospective study, 52 patients (50 males; mean age 29.5 years) underwent secondary reconstructions (2009–2020) for proximal pole (38.5%, n = 20) and waist non-unions (61.5%, n = 32). Treatments included non-vascularized iliac crest grafts (17 patients), vascularized pedicled distal radius grafts (26), and free medial femoral condyle flaps (9). Union and scaphoid alignment were assessed by CT, while carpal alignment and arthrosis were evaluated using radiographs. Statistical analysis employed chi-square, Fisher's exact, Mann-Whitney U, and McNemar tests (R v4.4.2; p ≤ 0.05).ResultsUnion rates differed significantly between proximal pole (40%, 8/20) and waist non-unions (68.75%, 22/32; p = 0.04). Graft type (p = 0.616), osteosynthesis method (p = 0.827), age (p = 0.095), smoking (p = 0.582), avascular necrosis (p = 0.42), and prior surgeries (p = 0.974) showed no significant association with union. Proximal pole non-unions with AVN trended toward lower union (22.2% vs. 54.5% without AVN), though this was not statistically significant. In patients achieving union, scaphoid humpback deformity was corrected in 9/15 cases (p = 0.0348), and dorsal intercalated segment instability improved significantly (p = 0.0143). Functionally, the union group had an average extension-flexion of 112° (81% of the healthy wrist) and radial-/ulnar adduction of 40° (72% of the unaffected wrist), with grip strength averaging 42 kg (range 25.2-59.7) and a DASH score of 11 (range 0–67). The non-union group showed 114° extension-flexion (91% of the unaffected wrist) and 38° ulnar/radial abduction (78% of the healthy wrist), with grip strength averaging 46 kg (range 37.6-59.3; 89% of the unaffected wrist) and a DASH score of 10 (range 3–33).DiscussionSecondary scaphoid reconstruction demonstrates location-dependent success. The decision between secondary reconstruction, which aims to restore anatomical integrity, and salvage procedures, which prioritize predictable outcomes, hinges on balancing union potential, functional results, and patient preferences. A tailored approach remains essential to align treatment goals with individual needs

Comparative analysis of cell death induction by Taurolidine in different malignant human cancer cell lines

<p>Abstract</p> <p>Background</p> <p>Taurolidine (TRD) represents an anti-infective substance with anti-neoplastic activity in many malignant cell lines. So far, the knowledge about the cell death inducing mechanisms and pathways activated by TRD is limited. The aim of this study was therefore, to perform a comparative analysis of cell death induction by TRD simultaneously in different malignant cell lines.</p> <p>Materials and methods</p> <p>Five different malignant cell lines (HT29/Colon, Chang Liver/Liver, HT1080/fibrosarcoma, AsPC-1/pancreas and BxPC-3/pancreas) were incubated with increasing concentrations of TRD (100 μM, 250 μM and 1000 μM) for 6 h and 24 h. Cell viability, apoptosis and necrosis were analyzed by FACS analysis (Propidiumiodide/AnnexinV staining). Additionally, cells were co-incubated with the caspase Inhibitor z-VAD, the radical scavenger N-Acetylcystein (NAC) and the Gluthation depleting agent BSO to examine the contribution of caspase activation and reactive oxygen species in TRD induced cell death.</p> <p>Results</p> <p>All cell lines were susceptible to TRD induced cell death without resistance toward this anti-neoplastic agent. However, the dose response effects were varying largely between different cell lines. The effect of NAC and BSO co-treatment were highly different among cell lines - suggesting a cell line specific involvement of ROS in TRD induced cell death. Furthermore, impact of z-VAD mediated inhibition of caspases was differing strongly among the cell lines.</p> <p>Conclusion</p> <p>This is the first study providing a simultaneous evaluation of the anti-neoplastic action of TRD across several malignant cell lines. The involvement of ROS and caspase activation was highly variable among the five cell lines, although all were susceptible to TRD induced cell death. Our results indicate, that TRD is likely to provide multifaceted cell death mechanisms leading to a cell line specific diversity.</p

Persistent alveolar soft-part sarcoma with liver metastasis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Alveolar soft-part sarcomas are rare, slow-growing tumors that metastasize commonly via vascular routes to the lungs, bones, lymph nodes and brain, causing morbidity and mortality. To the best of our knowledge, this is the first case describing metastasis to the liver reported from Nigeria.</p> <p>Case presentation</p> <p>A 57-year-old man of the Urhobo ethnic group of Nigeria presented with a persistent mass in his left calf. It was initially diagnosed as soft-tissue sarcoma, and its associated systemic effects lead to his death before a histological diagnosis could be obtained.</p> <p>Conclusions</p> <p>Alveolar soft-part sarcoma with metastasis to the liver can occur in our region (northeast Africa), and a high index of suspicion is required to make an early diagnosis, followed by prompt surgical excision with clear margins in order to prevent mortality.</p

Gene expression analysis of cell death induction by Taurolidine in different malignant cell lines

<p>Abstract</p> <p>Background</p> <p>The anti-infective agent Taurolidine (TRD) has been shown to have cell death inducing properties, but the mechanism of its action is largely unknown. The aim of this study was to identify potential common target genes modulated at the transcriptional level following TRD treatment in tumour cell lines originating from different cancer types.</p> <p>Methods</p> <p>Five different malignant cell lines (HT29, Chang Liver, HT1080, AsPC-1 and BxPC-3) were incubated with TRD (100 μM, 250 μM and 1000 μM). Proliferation after 8 h and cell viability after 24 h were analyzed by BrdU assay and FACS analysis, respectively. Gene expression analyses were carried out using the <it>Agilent </it>-microarray platform to indentify genes which displayed conjoint regulation following the addition of TRD in all cell lines. Candidate genes were subjected to <it>Ingenuity Pathways Analysis </it>and selected genes were validated by qRT-PCR and Western Blot.</p> <p>Results</p> <p>TRD 250 μM caused a significant inhibition of proliferation as well as apoptotic cell death in all cell lines. Among cell death associated genes with the strongest regulation in gene expression, we identified pro-apoptotic transcription factors (EGR1, ATF3) as well as genes involved in the ER stress response (PPP1R15A), in ubiquitination (TRAF6) and mitochondrial apoptotic pathways (PMAIP1).</p> <p>Conclusions</p> <p>This is the first conjoint analysis of potential target genes of TRD which was performed simultaneously in different malignant cell lines. The results indicate that TRD might be involved in different signal transduction pathways leading to apoptosis.</p

Arsenic trioxide exerts synergistic effects with cisplatin on non-small cell lung cancer cells via apoptosis induction

<p>Abstract</p> <p>Background</p> <p>Despite multidisciplinary treatment, lung cancer remains a highly lethal disease due to poor response to chemotherapy. The identification of therapeutic agents with synergistic effects with traditional drugs is an alternative for lung cancer therapy. In this study, the synergistic effects of arsenic trioxide (As₂O₃) with cisplatin (DDP) on A549 and H460 non-small cell lung cancer (NSCLC) cells were explored.</p> <p>Methods</p> <p>A549 and H460 human lung cancer cells were treated with As₂O₃and/or DDP. Cell growth curves, cell proliferation, cell cycle, and apoptosis of human cancer cell lines were determined by the 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) method, clonogenic assay, and flow cytometry (FCM). Apoptosis was further assessed by TUNEL staining. Cell cycle and apoptosis related protein p21, cyclin D1, Bcl-2, bax, clusterin, and caspase-3 were detected by western blot.</p> <p>Results</p> <p>MTT and clonogenic assay showed As₂O₃within 10^-2μM to 10 μM exerted inhibition on the proliferation of NSCLC cells, and 2.5 μM As₂O₃exerted synergistic inhibition on proliferation with 3 μg/ml DDP. The combination indices (CI) for A549 and H460 were 0.5 and 0.6, respectively, as confirmed by the synergism of As₂O₃with DDP. FCM showed As₂O₃did not affect the cell cycle. The G0/G1 fraction ranged from 57% to 62% for controlled A549 cells and cells treated with As₂O₃and/or DDP. The G0/G1 fraction ranged from 37% to 42% for controlled H460 cells and cells treated with As₂O₃and/or DDP. FCM and TUNEL staining illustrated that the combination of As₂O₃and DDP provoked synergistic effects on apoptosis induction based on the analysis of the apoptosis index. Western blotting revealed that the expression of cell cycle related protein p21 and cyclin D1 were not affected by the treatments, whereas apoptosis related protein bax, Bcl-2, and clusterin were significantly regulated by As₂O₃and/or DDP treatments compared with controls. The expression of caspase-3 in cells treated with the combination of As₂O₃and DDP did not differ from that in cells treated with a single agent.</p> <p>Conclusion</p> <p>As₂O₃exerted synergistic effects with DDP on NSCLC cells, and the synergistic effects were partly due to the induction of caspase-independent apoptosis.</p