Abnormalities of Coagulation and Fibrinolysis Assessed by Thromboelastometry in an Endotoxic Shock Model in Piglets Treated with Nitric Oxide and Hydrocortisone.

This is an animal model study to investigate changes in hemostasis during endotoxemic shock and to determine whether the combination of inhaled nitric oxide (iNO) + intravenous hydrocortisone had an effect on clot formation and fibrinolysis. iNO selectively decreases pulmonary artery pressure, without affecting cardiac index or systemic vascular resistance; however, the results of studies on the possible consequences of iNO administration on coagulation are inconsistent and require further research. Thirty-four piglets were included. Administering endotoxin caused severe hypodynamic shock. Half of the animals received iNO (30 ppm) + hydrocortisone, starting 3 h after endotoxin infusion and continuing to the end of the study. All animals developed coagulation disorders, manifested by a tendency to hypocoagulation; at the same time, fibrinolysis was impaired. Coagulation and fibrinolysis disorders persisted after endotoxin infusion was discontinued, with worse severity in the animals that died before the study was terminated. Administering iNO + hydrocortisone did not cause further changes in coagulation and fibrinolysis parameters, either during or after the endotoxin challenge, suggesting that potential therapeutic interventions with iNO to lower pulmonary arterial pressure will not affect hemostasis.

Daytime plasma cortisol and cortisol response to dexamethasone suppression are associated with a prothrombotic state in hypertension.

Background and aims: A prothrombotic state was demonstrated in patients with Cushing's syndrome and is involved in the development and progression of cardiovascular and renal damage in hypertensive patients. This study was designed to examine the relationships between cortisol secretion and the hemostatic and fibrinolytic systems in hypertension. Methods: In 149 middle-aged, nondiabetic, essential hypertensive patients free of cardiovascular and renal complications, we measured hemostatic markers that express the spontaneous activation of the coagulation and fibrinolytic systems and assessed daily cortisol levels (8 AM, 3 PM, 12 AM; area under the curve, AUC-cortisol) together with the cortisol response to dexamethasone overnight suppression (DST-cortisol). Results: Plasma levels of D-dimer (D-dim), prothrombin fragment 1 + 2 (F1 + 2), and von Willebrand factor (vWF) were progressively and significantly higher across tertiles of AUC-cortisol and DST-cortisol, whereas no differences were observed in fibrinogen, tissue plasminogen activator, plasminogen activator inhibitor-1, antithrombin III, protein C, and protein S. D-dim, F1 + 2, and vWF were significantly and directly correlated with age and both AUC-cortisol and DST-cortisol. Multivariate regression analysis showed that both AUC-cortisol and DST-cortisol were related to plasma D-dim, F1 + 2, and vWF independently of age, body mass index, blood pressure, and renal function. Conclusion: Greater daily cortisol profile and cortisol response to overnight suppression are independently associated with a prothrombotic state in hypertensive patients and might contribute to the development of organ damage and higher risk of cardiovascular complications.

Outcomes of slow coagulation transscleral cyclophotocoagulation in a predominantly African American glaucoma population.

Purpose: To evaluate outcomes of slow coagulation transscleral cyclophotocoagulation (SC-TSCPC) in a primarily African American patient population with glaucoma. Methods: A retrospective chart review was performed for 104 consecutive cases of SC-TSCPC by a single surgeon between November 6, 2019-September 7, 2023. Power ranged from 1150 to 1500 mW, duration was 4 s, and number of spots ranged from 10 to 25. Exclusion criteria were diagnosis of neovascular glaucoma, prior CPC, visual acuity (VA) of no light perception or unable to be assessed due to patient's mental status, aphakia, or follow-up <3 months. The primary outcome measure was surgical success defined as an intraocular pressure (IOP) of 6-21 mmHg with a ≥20 % reduction from baseline, no glaucoma re-operation, and no loss of light-perception. Secondary outcome measures included VA, glaucoma medication use, and post-surgical complications. Analysis was also stratified by lens status as literature suggests a greater IOP-lowering effect in pseudophakic eyes after CPC. Results: There were 28 eligible patients (6 phakic, 22 pseudophakic) included in this analysis. Mean follow-up was 11.6 ± 8.3 months, and 14 patients had postoperative year 1 data available. The mean age was 75.2 ± 13.9 years, 42.9 % were female, and 92.9 % were African American, reflective of the demographics of the local community. The cumulative success rate was 68.5 % at 1 year and did not differ significantly between phakic and pseudophakic patients. Mean VA worsened from 20/600 preoperatively to 20/1050 at last follow-up (P = 0.04) and was marginally worse in the phakic group (P = 0.15). Mean IOP decreased from 31.1 ± 13.2 mmHg on 4.0 ± 1.5 medications preoperatively to 13.8 ± 7.1 mmHg on 2.6 ± 1.5 medications at last follow-up (P < 0.001; P < 0.01), with a more pronounced effect among pseudophakic patients. 85.7 % of patients had prolonged anterior chamber (AC) inflammation beyond 1 month, which persisted in 10.7 % at last follow-up. The cystoid macular edema (CME) rate was 21.4 %, with 10.7 % persistent at last follow-up. Conclusions: SC-TSCPC is an effective, non-incisional IOP-lowering procedure in phakic and pseudophakic eyes that may not otherwise be ideal candidates for incisional glaucoma surgery. Pseudophakic eyes may experience larger reductions in IOP, however, laser settings can be titrated on a case-by-case basis depending on individual patients' goals. There was a higher incidence of prolonged AC inflammation and CME in our cohort compared to similar studies which report rates of 12.7 % and 2.7 %, respectively. Although the significance of such complications may differ based on the visual potential of each patient, these findings support existing literature that African American patients can have greater incidence of inflammation and subsequent sequalae after ocular surgery.

ROTEM could be useful for lupus anticoagulant hypoprothrombinemia syndrome.

BACKGROUND: Lupus anticoagulant-hypoprothrombinemia syndrome (LAHPS) is a rare disease caused by acquired factor II (FII) deficiency and lupus anticoagulant. Patients with LAHPS typically present with thrombosis and bleeding. However, little information is available on the evaluation of coagulation potential in patients with LAHPS. We examined global coagulation potentials in patients with LAHPS during the clinical course in this study. METHODS: Coagulation potentials in two pediatric patients with LAHPS were assessed by measuring clotting time (CT) and clot formation time using Ca2+-triggered rotational thromboelastometry (ROTEM), CT and maximum coagulation velocity using clot waveform analysis (CWA), and lag time and peak thrombin using the thrombin generation assay (TGA). The day of admission was defined as day 0. RESULTS: In case 1, the bleeding symptoms disappeared by day 5. However, the TGA and CWA results were markedly lower than normal, although FII activity (FII:C) returned to within the normal range by day 14. In contrast, ROTEM revealed a recovery to near-normal levels (day 14). All coagulation parameters (day 80) were within normal ranges. In case 2, coagulation potential was severely depressed until day 12, although FII:C returned to normal levels. Bleeding symptoms disappeared on day 19, and the ROTEM data revealed that the parameters were close to the normal range. The coagulation parameters in all assays were normalized on day 75. CONCLUSIONS: Recovery of coagulation potential in patients with LAHPS was slower than the recovery of FII:C. Moreover, ROTEM appeared to be clinically useful for assessing coagulation potential in patients with LAHPS.

An in vitro study of coagulation evaluation in obstetric hemorrhage for pregnancy-induced hypertension with coagulation and platelet function analyzer.

This study aimed to establish in vitro hemodilution and resupplementation assays for obstetric hemorrhage in pregnancy-induced hypertension (PIH) and to monitor the coagulation function dynamically using a coagulation and platelet function analyzer. Forty-seven singleton pregnant women were divided into normal (n = 24) and PIH (n = 23) groups. Peripheral blood samples were used to construct the assays, and the activated clotting time (ACT), clotting rate (CR), and platelet function index (PF) were measured. The results showed that the baseline ACT was higher in the PIH group (p < 0.01). Hemodilution assays showed decreased ACT and increased CR and PF, with ACT changes significantly lower in the PIH group (p < 0.05). CR changed most in both groups at lower dilution ratios (35% to 50%), while ACT changed most at a higher dilution ratio (75%). In the resupplementation assay, ACT exhibited the most significant response. The analyzer effectively detected differences between pregnant women with and without PIH. Thus, we need to pay more attention to the changes of ACT in the actual clinical application to assess the coagulation status of parturients.

Epidural Hematoma in Minor Hepatic Metastasectomy.

Liver resection poses many challenges for the anesthesiologist, including intraoperative hemodynamic instability, postoperative pain, and risk of coagulopathy. We report a case of epidural hematoma after epidural catheter removal, following a minor liver single metastasectomy. The main purpose of this case report is to bring to light the false security provided by traditional coagulation parameters and whether further investigation should be considered in selected cases, before handling neuraxial catheters. Alterations in coagulation after a partial hepatectomy remain poorly understood; thus, we believe that additional hemostatic values such as viscoelastic testing might be considered to better assess these patients.

Viscoelastic blood coagulation testing system enabled by a non-contact triboelectric angle sensor.

Thromboelastography (TEG) remains a convenient and effective viscoelastic blood coagulation testing device for guiding blood component transfusion and assessing the risk of thrombosis. Here, a TEG enabled by a non-contact triboelectric angle sensor (NTAS) with a small size (∼7 cm3) is developed for assessing the blood coagulation system. With the assistance of a superelastic torsion wire structure, the NTAS-TEG realizes the detection of blood viscoelasticity. Benefiting from a grating and convex design, the NTAS holds a collection of compelling features, including accurate detection of rotation angles from -2.5° to 2.5°, high linearity (R 2 = 0.999), and a resolution of 0.01°. Besides, the NTAS exhibits merits of low cost and simplified fabrication. Based on the NTAS-TEG, a viscoelastic blood coagulation detection and analysis system is successfully constructed, which can provide a graph and parameters associated with clot initiation, formation, and stability for clinicians by using 0.36 mL of whole blood. The system not only validates the feasibility of the triboelectric coagulation testing sensor, but also further expands the application of triboelectric sensors in healthcare.

Organ Dysfunction in Sepsis-associated Intravascular Coagulation.

Sepsis is frequently associated with disseminated intravascular coagulation (DIC) and multiple organ damage. It is widely accepted that DIC is not merely a complication but also plays a role in the development of organ dysfunction. Thrombus formation in the microvasculature leads to impaired tissue perfusion and organ damage. Activated neutrophils interacting with platelets, endothelial injury, and an imbalance of coagulation and fibrinolysis are the essence of thromboinflammation induced in sepsis-associated DIC. The above mechanisms are typically seen in sepsis-associated acute kidney injury (AKI), and the development of AKI is known to be strongly associated with the severity of sepsis. It is important to recognize the pathway of this mechanism in the context of sepsis management.

Circulating microaggregates as biomarkers for the Post-COVID syndrome.

CoVID-19 can develop into Post-COVID syndrome of potentially high morbidity, with procoagulation and reactivation of dormant viral infections being hypothesized pathophysiological mechanisms. We report on a patient suffering from fatigue, post exertional malaise, pain and neurological symptoms as a consequence of the second CoVID infection. Using live confocal microscopy on native whole blood samples we detected microaggregates of thrombocytes, leukocytes and plasma proteins in peripheral blood. In addition, there was specific cellular immunological reactivity to EBV. Upon anticoagulatory and virustatic pharmacological therapy we observed dissolution of microaggregates and significant stable clinical remission. We suggest to consider circulating microaggregates as a morphological indicator of chronic post-COVID syndrome.

Gas-propelled nanomotors alleviate colitis through the regulation of intestinal immunoenvironment-hematopexis-microbiota circuits.

The progression of ulcerative colitis (UC) is associated with immunologic derangement, intestinal hemorrhage, and microbiota imbalance. While traditional medications mainly focus on mitigating inflammation, it remains challenging to address multiple symptoms. Here, a versatile gas-propelled nanomotor was constructed by mild fusion of post-ultrasonic CaO2 nanospheres with Cu2O nanoblocks. The resulting CaO2-Cu2O possessed a desirable diameter (291.3 nm) and a uniform size distribution. It could be efficiently internalized by colonic epithelial cells and macrophages, scavenge intracellular reactive oxygen/nitrogen species, and alleviate immune reactions by pro-polarizing macrophages to the anti-inflammatory M2 phenotype. This nanomotor was found to penetrate through the mucus barrier and accumulate in the colitis mucosa due to the driving force of the generated oxygen bubbles. Rectal administration of CaO2-Cu2O could stanch the bleeding, repair the disrupted colonic epithelial layer, and reduce the inflammatory responses through its interaction with the genes relevant to blood coagulation, anti-oxidation, wound healing, and anti-inflammation. Impressively, it restored intestinal microbiota balance by elevating the proportions of beneficial bacteria (e.g., Odoribacter and Bifidobacterium) and decreasing the abundances of harmful bacteria (e.g., Prevotellaceae and Helicobacter). Our gas-driven CaO2-Cu2O offers a promising therapeutic platform for robust treatment of UC via the rectal route.

Comparative analysis of thrombin generation platforms for patients with coagulation factor deficiencies: A comprehensive assessment.

INTRODUCTION: Thrombin generation assays (TGAs) assess the overall functionality of the hemostatic system and thereby provide a reflection of the hemostatic capacity of patients with disorders in this system. Currently, four (semi-)automated TGA platforms are available: the Calibrated Automated Thrombogram, Nijmegen Hemostasis Assay, ST Genesia and Ceveron s100. In this study, we compared their performance for detecting patients with congenital single coagulation factor deficiencies. MATERIALS AND METHODS: Pooled patient samples, healthy control samples and normal pooled plasma were tested on all four platforms, using the available reagents that vary in tissue factor and phospholipid concentrations. The TGA parameters selected for analysis were peak height and thrombin potential. Results were normalized by using the calculated mean of healthy controls and a correction for between-run variation. Outcomes were presented as relative values, with the mean of healthy controls standardized to 100 %. RESULTS: Across all platforms and reagents used, thrombin potentials and peak heights of samples with coagulation factor deficiencies were lower than those of healthy controls. Reagents designed for bleeding tendencies yielded the lowest values on all platforms (relative median peak height 19-32 %, relative median thrombin potential 19-45 %). Samples representing more severe coagulation factor deficiencies generally exhibited lower relative peak heights and thrombin potentials. CONCLUSIONS: Thrombin generation assays prove effective in differentiating single coagulation factor deficient samples from healthy controls, with modest discrepancies observed between the platforms. Reagents designed for assessing bleeding tendencies, featuring the lowest tissue factor and phospholipid concentrations, emerged as the most suitable option for detecting coagulation factor deficiencies.

Coagulation factor XI in cirrhosis does not predict thrombo-hemorrhagic complications and hepatic decompensation.

INTRODUCTION: Factor XI (FXI) is associated with thrombosis in patients without liver disease, but it alterations and prognostic value in cirrhosis are uncertain. PATIENTS AND METHODS: We studied a prospective cohort of cirrhosis patients determining FXI and its association with portal vein thrombosis (PVT), bleeding, and hepatic decompensation/ACLF during 1-year follow-up. Odds ratios (OR) and 95 % CIs were calculated using logistic regression. RESULTS: We included 183 patients (Child-Pugh [CP] A/B/C 57/59/57). FXI was reduced in cirrhosis, decreasing with CP stage (78 % [66-94] vs. 58 % [44-78] vs. 41 % [30-52] in CP A, B, and C, respectively; p < 0.001). FXI was correlated with MELD score (rho: -0.6, p < 0.001), INR (rho: -0.6, p < 0.001), and platelet count (rho: 0.4, p < 0.001). Sixteen patients (8.7 %) experienced PVT, which only predictor was baseline platelet count (OR: 0.94; CI95 %: 0.91-0.97, p < 0.001). Bleeding occurred in 7 patients (3.8 %). Cirrhosis severity, platelet count, fibrinogen, and FXI (60% vs. 78 %; p = 0.2) were comparable between bleeding and non-bleeding individuals. Finally, no association was found between FXI and hepatic decompensation/ACLF, which were predicted by lower albumin and platelet count, respectively. CONCLUSION: FXI seems not to be responsible for thrombosis and cirrhosis progression. The lack of association between low FXI and bleeding events, however, indirectly opens to future studies evaluating FXI inhibitors in cirrhosis.

Comparative evaluation of different pre-treatment alternatives for granular media filters treating greywater and their ranking using analytical hierarchy process.

In this study, the performance of four different pre-treatment alternatives for granular media filtration, namely, settling, aeration, coarse media filtration and chemical coagulation were compared experimentally. Further, analytical hierarchy process (AHP) was used to compare their performance based on economic, environmental, technical and performance criteria. Performance of settling and aeration were evaluated up to 24 h duration. The coarse media filter was intermittently operated with 10 L of greywater in downflow mode while alum was used for chemical coagulation. Experimental results showed that settling up to 6 h did not show significant removal of different pollutants whereas 24 h settling resulted in moderate removal of turbidity and organic content but was not efficient in the removal of nutrients and faecal coliforms. Chemical coagulation reduced 93, 66, 48 and 97% of turbidity, COD, NH4-N and faecal coliforms, respectively from greywater but resulted in excessive sludge generation and is difficult to adopt on-site and requires skilled supervision. Coarse filtration of greywater resulted in 61, 41, 36 and 35% removal of turbidity, COD, PO4-P and faecal coliforms, respectively. Considering different criteria AHP gave coarse filtration as the best pre-treatment option to the granular media filters treating greywater.

Predictive value of thrombin-antithrombin III complex and tissue plasminogen activator-inhibitor complex biomarkers in assessing the severity of early-stage acute pancreatitis.

BACKGROUND AND AIM: The development of acute pancreatitis (AP) is strongly linked to blood clotting and fibrinolysis issues. Modern clinical practices now utilize advanced blood markers like thrombin-antithrombin III complex (TAT), plasmin-α2-plasmin inhibitor complex, thrombomodulin (TM), and tissue plasminogen activator-inhibitor complex (t-PAIC) to assess thrombosis risk. Our study used a highly sensitive chemiluminescence technique to measure these markers in AP patients, aiming to determine their early predictive value for AP severity. METHODS: There were 173 patients with AP, all of whom developed symptoms within 72 h; 102 individuals had onset symptoms within 48 h. The biomarkers were measured upon admission before determining the severity of AP. RESULTS: The levels of TAT, plasmin-α2-plasmin inhibitor complex, TM, and t-PAIC were significantly higher in the severe acute pancreatitis (SAP) group compared with the mild acute pancreatitis and moderate severe acute pancreatitis groups. For the patients within 72 h of onset, TAT, TM, and t-PAIC predicted the occurrence of SAP. For the patients within 48 h of onset, TAT and t-PAIC predicted the occurrence of SAP. The area under the curve (AUC) of prediction models is similar to Bedside Index for Severity in Acute Pancreatitis (BISAP) but significantly higher than C-reactive protein (P < 0.05). Notably, t-PAIC had a larger AUC than TAT, BISAP, and C-reactive protein. CONCLUSION: In the initial 48 h, plasma TAT and t-PAIC levels may predict the development of SAP. Within 72 h, plasma levels of TAT, TM, and t-PAIC may predict the development of SAP, and the TAT + TM + t-PAIC prediction model achieved a maximum AUC of 0.915, comparable to BISAP.

Macrophage fate: to kill or not to kill?

Macrophages are dynamic innate immune cells that either reside in tissue, serving as sentinels, or recruited as monocytes from bone marrow into inflamed and infected tissue. In response to cues in the tissue microenvironment (TME), macrophages polarize on a continuum toward M1 or M2 with diverse roles in progression and resolution of disease. M1-like macrophages exhibit proinflammatory functions with antimicrobial and anti-tumorigenic activities, while M2-like macrophages have anti-inflammatory functions that generally resolve inflammatory responses and orchestrate a tissue healing process. Given these opposite phenotypes, proper spatiotemporal coordination of macrophage polarization in response to cues within the TME is critical to effectively resolve infectious disease and regulate wound healing. However, if this spatiotemporal coordination becomes disrupted due to persistent infection or dysregulated coagulation, macrophages' inappropriate response to these cues will result in the development of diseases with clinically unfavorable outcomes. Since plasticity and heterogeneity are hallmarks of macrophages, they are attractive targets for therapies to reprogram toward specific phenotypes that could resolve disease and favor clinical prognosis. In this review, we discuss how basic science studies have elucidated macrophage polarization mechanisms in TMEs during infections and inflammation, particularly coagulation. Therefore, understanding the dynamics of macrophage polarization within TMEs in diseases is important in further development of targeted therapies.

Experimental Verification of Erchen Decoction Plus Huiyanzhuyu Decoction in the Treatment of Laryngeal Squamous Cell Carcinoma Based on Network Pharmacology.

BACKGROUND: The prescription of Chinese herbal medicine (CHM) consists of multiple herbs that exhibit synergistic effects due to the presence of multiple components targeting various pathways. In clinical practice, the combination of Erchen decoction and Huiyanzhuyu decoction (EHD) has shown promising outcomes in treating patients with laryngeal squamous cell carcinoma (LSCC). However, the underlying mechanism by which EHD exerts its therapeutic effects in LSCC remains unknown. METHODS: Online databases were utilized for the analysis and prediction of the active constituents, targets, and key pathways associated with EHD in the treatment of LSCC. The protein-protein interaction (PPI) network of common targets was constructed and visualized using Cytoscape 3.8.1 software. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to investigate the functional roles of core targets within the PPI network. Protein clustering was conducted utilizing the MCODE plug-in. The obtained results highlight the principal targets and pathways involved. Subsequently, clinical samples were collected to validate alterations in the levels of these main targets through Western blotting (WB) and immunohistochemistry (IHC). Furthermore, both in vivo and in vitro experiments were conducted to investigate the therapeutic effects of EHD on healing LSCC and elucidate its underlying mechanism. Additionally, to ensure experimental reliability and reproducibility, quality control measures utilizing HPLC were implemented for EHD herbal medicine. RESULTS: The retrieval and analysis of databases in EHD medicine and LSCC disease yielded a total of 116 overlapping targets. The MCODE plug-in methods were utilized to acquire 8 distinct protein clusters through protein clustering. The findings indicated that both the first and second clusters exhibited a size greater than 6 scores, with key genes PI3K and ErbB occupying central positions, while the third and fourth clusters were associated with proteins in the PI3K, STAT3, and Foxo pathways. GO functional analysis reported that these targets had associations mainly with the pathway of p53 mediated DNA damage and negative regulation of cell cycle in terms of biological function; the death-induced signaling complex in terms of cell function; transcription factor binding and protein kinase activity in terms of molecular function. The KEGG enrichment analysis demonstrated that these targets were correlated with several signaling pathways, including PI3K-Akt, FoxO, and ErbB2 signaling pathway. On one hand, we observed higher levels of key genes such as P-STAT3, P-PDK1, P-Akt, PI3K, and ErbB2 in LSCC tumor tissues compared to adjacent tissues. Conversely, FOXO3a expression was lower in LSCC tumor tissues. On the other hand, the key genes mentioned above were also highly expressed in both LSCC xenograft nude mice tumors and LSCC cell lines, while FOXO3a was underexpressed. In LSCC xenograft nude mice models, EHD treatment resulted in downregulation of P-STAT3, P-PDK1, PI3K, P-AKT, and ErbB2 protein levels but upregulated FOXO3a protein level. EHD also affected the levels of P-STAT3, P-PDK1, PI3K, P-AKT, FOXO3a, and ErbB2 proteins in vitro: it inhibited P-STAT3, P-AKT, and ErbB2, while promoting FOXO3a; however, it had no effect on PDK1 protein. In addition, HPLC identified twelve compounds accounting for more than 30% within EHD. The findings from this study can serve as valuable guidance for future experimental investigations. CONCLUSION: The possible mechanism of EHD medicine action on LSCC disease is speculated to be closely associated with the ErbB2/PI3K/AKT/FOXO3a signaling pathway.

Modeling the distribution of enzymes on lipid vesicles: A novel framework for surface-mediated reactions in coagulation.

Blood coagulation is a network of biochemical reactions wherein dozens of proteins act collectively to initiate a rapid clotting response. Coagulation reactions are lipid-surface dependent, and this dependence is thought to help localize coagulation to the site of injury and enhance the association between reactants. Current mathematical models of coagulation either do not consider lipid as a variable or do not agree with experiments where lipid concentrations were varied. Since there is no analytic rate law that depends on lipid, only apparent rate constants can be derived from enzyme kinetic experiments. We developed a new mathematical framework for modeling enzymes reactions in the presence of lipid vesicles. Here the concentrations are such that only a fraction of the vesicles harbor bound enzymes and the rest remain empty. We call the lipid vesicles with and without enzyme TF:VIIa+ and TF:VIIa- lipid, respectively. Since substrate binds to both TF:VIIa+ and TF:VIIa- lipid, our model shows that excess empty lipid acts as a strong sink for substrate. We used our framework to derive an analytic rate equation and performed constrained optimization to estimate a single, global set of intrinsic rates for the enzyme-substrate pair. Results agree with experiments and reveal a critical lipid concentration where the conversion rate of the substrate is maximized, a phenomenon known as the template effect. Next, we included product inhibition of the enzyme and derived the corresponding rate equations, which enables kinetic studies of more complex reactions. Our combined experimental and mathematical study provides a general framework for uncovering the mechanisms by which lipid mediated reactions impact coagulation processes.

Influence of chitosan properties and operating parameters on the flocculation efficiency and harvesting of microalgae (Scenedesmus sp.).

Physicochemical and structural characteristics of chitosan prepared from Deep-sea shrimp (DCs), including degree of deacetylation (DD), molecular weight (Mw), viscosity, crystallinity index (CrI) and surface morphology were compared with a commercial chitosan (CCs). The DCs had a higher DD of 81.33 ± 0.40 %, whereas the CCs had a lower DD of 74.62 ± 0.64 %. Additionally, the DCs exhibited a lower Mw of 192.47 ± 2.5 kDa and viscosity of 646.00 ± 4.00 cP compared to the CCs, which had a Mw of 202.44 ± 0.28 kDa and viscosity of 689.67 ± 5.91 cP. This study investigated the influence of chitosan properties, particularly DD and Mw on the harvesting of Scenedesmus sp. along with the chitosan dosage, pH of the culture medium, mixing speed and time. Under optimal operating conditions, the microalgae removal efficiency of the DCs reached a significantly higher level (94.71 ± 0.20 %) compared to that of CCs (88.25 ± 0.41 %). Chitosan with a higher DD and low Mw demonstrated superior flocculation efficiency. The results highlight the significance of DD and Mw of chitosan and its influence on the flocculation of microalgae, providing valuable insights for optimizing the harvesting process with the non-toxic and natural flocculent, chitosan.

Magnetic resonance imaging-guided focused ultrasound thalamotomy for essential tremor in a patient with von Willebrand disease: perioperative optimization for patients with coagulopathies. Illustrative case.

BACKGROUND: Essential tremor (ET) is one of the most common movement disorders worldwide. In medically refractory ET, deep brain stimulation (DBS) of the ventral intermediate nucleus of the thalamus is the current standard of care. However, DBS carries an inherent 2% to 3% risk of hemorrhage, a risk that can be much higher in patients with concomitant coagulopathy. Magnetic resonance imaging-guided focused ultrasound (MRgFUS) thalamotomy is a surgical alternative that is highly effective in treating ET, with no reports of intracranial hemorrhage to date. OBSERVATIONS: This is the first documented case of successful MRgFUS thalamotomy in a patient with von Willebrand disease (VWD). A 60-year-old left-handed male had medically refractory ET, VWD type 2B, and a family history of clinically significant hemorrhage after DBS. He underwent right-sided MRgFUS thalamotomy and received a perioperative course of VONVENDI (recombinant von Willebrand factor) to ensure appropriate hemostasis. Postprocedure imaging confirmed a focal lesion in the right thalamus without evidence of hemorrhage. The patient reported 90% improvement of his left-hand tremor and significant improvement in his quality of life without obvious side effects. LESSONS: MRgFUS thalamotomy with peri- and postoperative hematological management is a promising alternative to DBS for patients with underlying coagulopathies.

Partitioning purification, biochemical characterization, and milk coagulation efficiency of protease from a newly Streptomyces sp. isolate.

An actinobacteria strain was isolated from an olive waste mill and tested for protease production on skimmed milk media. The strain identification was achieved through both 16 S rDNA sequencing and phenotypic characterization. The enzyme was purified using the ammonium sulfate/t-butanol three-phase partitioning (TPP) method, followed by characterization to investigate the effect of pH, temperature, and various chemical agents. Subsequently, the enzyme was assessed for its milk coagulation activity. The strain belonging to the Streptomyces genera, exhibits significant phylogenetic and phenotypic differences from the aligned species, suggesting its novelty as a new strain. The enzyme was best separated in the TPP aqueous phase with a 5.35 fold and 56.25% yield. Optimal activity was observed at pH 9.0 and 60 °C, with more than half of the activity retained within the pH range of 7-10 over one hour. The protease demonstrated complete stability between 30 and 60 °C. While metallic ions enhanced enzyme activity, EDTA acted as an inhibitor. The enzyme displayed resistance to H2O2, SDS, Tween 80, and Triton X-100. Notably, it was activated in organic solvents (ethyl acetate, petroleum ether, and xylene), maintaining > 75% of its original activity in butanol, ethanol, and methanol. Additionally, the enzyme yielded high milk coagulant activity of 11,478 SU/mL. The new Streptomyces sp. protease revealed high activity and stability under a wide range of biochemical conditions. Its use in the dairy industry appears particularly promising. Further industrial process investigations will be valuable in determining potential uses for this enzyme.