Molecular and Cellular Mechanisms of Delayed Fracture Healing in Mmp10 (Stromelysin 2) Knockout Mice.

The remodeling of the extracellular matrix is a central function in endochondral ossification and bone homeostasis. During secondary fracture healing, vascular invasion and bone growth requires the removal of the cartilage intermediate and the coordinate action of the collagenase matrix metalloproteinase (MMP)-13, produced by hypertrophic chondrocytes, and the gelatinase MMP-9, produced by cells of hematopoietic lineage. Interfering with these MMP activities results in impaired fracture healing characterized by cartilage accumulation and delayed vascularization. MMP-10, Stromelysin 2, a matrix metalloproteinase with high homology to MMP-3 (Stromelysin 1), presents a wide range of putative substrates identified in vitro, but its targets and functions in vivo and especially during fracture healing and bone homeostasis are not well defined. Here, we investigated the role of MMP-10 through bone regeneration in C57BL/6 mice. During secondary fracture healing, MMP-10 is expressed by hematopoietic cells and its maximum expression peak is associated with cartilage resorption at 14 days post fracture (dpf). In accordance with this expression pattern, when Mmp10 is globally silenced, we observed an impaired fracture-healing phenotype at 14 dpf, characterized by delayed cartilage resorption and TRAP-positive cell accumulation. This phenotype can be rescued by a non-competitive transplant of wild-type bone marrow, indicating that MMP-10 functions are required only in cells of hematopoietic linage. In addition, we found that this phenotype is a consequence of reduced gelatinase activity and the lack of proMMP-9 processing in macrophages. Our data provide evidence of the in vivo function of MMP-10 during endochondral ossification and defines the macrophages as the lead cell population in cartilage removal and vascular invasion. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

The Role of Circulating Biomarkers in Peripheral Arterial Disease.

Peripheral arterial disease (PAD) of the lower extremities is a chronic illness predominantly of atherosclerotic aetiology, associated to traditional cardiovascular (CV) risk factors. It is one of the most prevalent CV conditions worldwide in subjects >65 years, estimated to increase greatly with the aging of the population, becoming a severe socioeconomic problem in the future. The narrowing and thrombotic occlusion of the lower limb arteries impairs the walking function as the disease progresses, increasing the risk of CV events (myocardial infarction and stroke), amputation and death. Despite its poor prognosis, PAD patients are scarcely identified until the disease is advanced, highlighting the need for reliable biomarkers for PAD patient stratification, that might also contribute to define more personalized medical treatments. In this review, we will discuss the usefulness of inflammatory molecules, matrix metalloproteinases (MMPs), and cardiac damage markers, as well as novel components of the liquid biopsy, extracellular vesicles (EVs), and non-coding RNAs for lower limb PAD identification, stratification, and outcome assessment. We will also explore the potential of machine learning methods to build prediction models to refine PAD assessment. In this line, the usefulness of multimarker approaches to evaluate this complex multifactorial disease will be also discussed.

Functional and transcriptomic analysis of extracellular vesicles identifies calprotectin as a new prognostic marker in peripheral arterial disease (PAD).

Peripheral arterial disease (PAD) is associated with a high risk of cardiovascular events and death and is postulated to be a critical socioeconomic cost in the future. Extracellular vesicles (EVs) have emerged as potential candidates for new biomarker discovery related to their protein and nucleic acid cargo. In search of new prognostic and therapeutic targets in PAD, we determined the prothrombotic activity, the cellular origin and the transcriptomic profile of circulating EVs. This prospective study included control and PAD patients. Coagulation time (Procoag-PPL kit), EVs cellular origin and phosphatidylserine exposure were determined by flow cytometry in platelet-free plasma (n = 45 PAD). Transcriptomic profiles of medium/large EVs were generated using the MARS-Seq RNA-Seq protocol (n = 12/group). The serum concentration of the differentially expressed gene S100A9, in serum calprotectin (S100A8/A9), was validated by ELISA in control (n = 100) and PAD patients (n = 317). S100A9 was also determined in EVs and tissues of human atherosclerotic plaques (n = 3). Circulating EVs of PAD patients were mainly of platelet origin, predominantly Annexin V positive and were associated with the procoagulant activity of platelet-free plasma. Transcriptomic analysis of EVs identified 15 differentially expressed genes. Among them, serum calprotectin was elevated in PAD patients (p < 0.05) and associated with increased amputation risk before and after covariate adjustment (mean follow-up 3.6 years, p < 0.01). The combination of calprotectin with hs-CRP in the multivariate analysis further improved risk stratification (p < 0.01). Furthermore, S100A9 was also expressed in femoral plaque derived EVs and tissues. In summary, we found that PAD patients release EVs, mainly of platelet origin, highly positive for AnnexinV and rich in transcripts related to platelet biology and immune responses. Amputation risk prediction improved with calprotectin and was significantly higher when combined with hs-CRP. Our results suggest that EVs can be a promising component of liquid biopsy to identify the molecular signature of PAD patients.

Insights into venous thromboembolism prevention in hospitalized cancer patients: Lessons from a prospective study.

Hospitalized cancer patients are at high risk of venous thromboembolism (VTE). Despite current recommendations in clinical guidelines, thromboprophylaxis with low molecular weight heparin (LMWH) is underused. We performed an observational prospective study to analyse factors influencing prophylaxis use, VTE events and mortality in cancer-hospitalized patients. 1072 consecutive adult cancer patients were included in an University Hospital from April 2014 to February 2017, and followed-up for 30 days after discharge. The rate of LMWH prophylaxis was 67.6% (95% confidence interval [CI] 64.7% to 70.4%), with a 2.8% rate of VTE events (95% CI 1.9% to 3.9%) and 3.5% rate of major bleeding events (95% CI 2.5% to 4.8%). 80% of VTE events occurred despite appropriate thromboprophylaxis. Overall, 30-day mortality rate was 13.2% (95% CI 11.2% to 15.3%). Active chemotherapy treatment, hospital stay ≥ 4 days, and metastatic disease were associated with a higher use of LMWH. On the contrary, patients with hematologic malignancies, anemia or thrombocytopenia were less prone to receive thromboprophylaxis. The main reasons for not prescribing LMWH prophylaxis were thrombocytopenia (23.9%) and active/recent bleeding (21.8%). The PRETEMED score, used for VTE risk stratification, correlated with 30-day mortality. There is room for improvement in thromboprophylaxis use among hospitalized-cancer patients, especially among those with hematologic malignancies. A relevant number of VTE events occurred despite prophylaxis with LMWH. Therefore, identification of risk factors for thromboprophylaxis failure is needed.

[New era in antiplatelet therapy based on results from recent clinical trials]. / Nueva era en la terapia antiplaquetar basada en los resultados de ensayos clínicos recientes.

Antiplatelet therapy has been successful in reducing mortality and morbidity in cardiovascular diseases (e.g. acute coronary syndromes). Recent advances in understanding the molecular basis of the role of platelets in atherothrombosis have enabled the development of new agents with the potential to further reduce mortality and morbidity. Some limitations associated with the use of aspirin and clopidogrel have led to potential alternatives, including more potent ADP antagonists such as prasugrel, ticagrelor, cangrelor, and thrombin receptor antagonists, which have shown additional benefit in large randomized controlled trials. These new agents open a realistic prospect of a personalized choice of the most appropriate antiplatelet therapy tailored for an individual patient and a clinical condition.

Randomized clinical trial on acute effects of i.v. iron sucrose during haemodialysis.

AIM: Haemodialysis induces endothelial dysfunction by oxidation and inflammation. Intravenous iron administration during haemodialysis could worsen endothelial dysfunction. The aim of this study was to ascertain if iron produces endothelial dysfunction and the possible neutralizing effect of N-acetylcysteine when infused before iron. The oxidative and inflammatory effects of iron during haemodialysis were also assessed. METHODS: Forty patients undergoing haemodialysis were studied in a randomized and cross-over design with and without N-acetylcysteine infused before iron sucrose (50 or 100 mg). Plasma Von Willebrand factor (vWF), soluble intercellular adhesion molecule-1 (sICAM-1) levels, malondialdehyde, total antioxidant capacity, CD11b/CD18 expression in monocytes, interleukin (IL)-8 in monocytes and plasma IL-8 were studied at baseline and during haemodialysis. RESULTS: Haemodialysis produced significant (P < 0.001) increase in plasma vWF, sICAM-1, malondialdehyde, IL-8 and CD11b/CD18 expression in monocytes, as well as decrease in total antioxidant capacity. Iron induced significant increase in plasma malondialdehyde and IL-8 in monocytes, but had no effect on total antioxidant capacity, CD11b/CD18 expression, plasma IL-8, vWF and sICAM-1. The addition of N-acetylcysteine to 50 mg of iron produced a significant (P = 0.040) decrease in malondialdehyde. CONCLUSION: Standard (100 mg) and low (50 mg) doses of iron during haemodialysis had no effects on endothelium. Iron only had minor effects on inflammation and produced an increase in oxidative stress, which was neutralized by N-acetylcysteine at low iron dose. Haemodialysis caused a significant increase in oxidative stress, inflammation and endothelial dysfunction markers.

Factores ligados a angiogénesis, coagulación y fibrinólisis en el pronóstico de pacientes con cáncer colorrectal / Clotting, fibrinolysis and angiogénesis linked factors in the prognosis of colorectal carcinoma patients

Las plaquetas implicadas en la angiogénesis tumoral secretan factor de crecimiento endotelial vascular (VEGF). Los niveles de inhibidor del activador de plasminógeno tipo 1 (PAI-1) podrían regular la degradación de la matriz extracelular durante la angiogénesis. Durante este proceso tiene lugar la activación del sistema de la coagulación-fibrinólisis, que representa un evento clínico desfavorable. El factor de Von Willebrand (vWf), el dímero D (DD) y el fibrinógeno son marcadores sensibles de estos procesos. El recuento de plaquetas y los niveles de VEGF, PAI-1, vWf, DD y fibrinógeno podrían predecir la evolución clínica en pacientes con cáncer. En este estudio correlacionamos los niveles de VEGF, PAI-1, vWf, DD y fibrinógeno en pacientes con carcinoma colorrectal (CCR) en estadios I a IV sometidos a cirugía, a quimioterapia o a ambos métodos, con el análisis patológico/inmunohistoquímico en pacientes en estadios I-III y con la respuesta al tratamiento, y el riesgo de muerte en pacientes en estadio IV. Treinta y dos pacientes con CCR localizado o localmente avanzado y 32 con CCR metastático fueron evaluados. Las muestras sanguíneas se extrajeron antes de la cirugía y antes y después de la quimioterapia basada en fluoropirimidinas. Los enfermos en estadio IV recibieron una mediana de 3 ciclos de quimioterapia, entre muestras. En los pacientes en estadio I a III, los niveles basales de VEGF, recuento de plaquetas, fibrinógeno y PAI-1 se correlacionaron con el estadio tumoral. Además, la expresión tumoral de p21 y c-myc se asoció con niveles más elevados de vWf e inferiores de DD, respectivamente. En tumores metastásicos, los niveles prequimioterapia y posquimioterapia de VEGF, PAI-1 y CA19.9 se encontraron relacionados con las tasas de progresión.

Epidemiologia e desfecho de pacientes cirúrgicos não cardíacos em unidades de terapia intensiva no Brasil / Epidemiology and outcomes of non-cardiac surgical patients in Brazilian intensive care units

OBJETIVO: Devido aos avanços da medicina e ao envelhecimento da população, a proporção de pacientes em risco de morte após cirurgias está aumentando. Nosso objetivo foi avaliar o desfecho e a epidemiologia de cirurgias não cardíacas em pacientes admitidos em unidade de terapia intensiva. MÉTODOS: Estudo prospectivo, observacional, de coorte, realizado em 21 unidades de terapia intensiva. Um total de 885 pacientes adultos, cirúrgicos, consecutivamente admitidos em unidades de terapia intensiva no período de abril a junho de 2006 foi avaliado e destes, 587 foram incluídos. Os critérios de exclusão foram; trauma, cirurgias cardíacas, neurológicas, ginecológicas, obstétricas e paliativas. Os principais desfechos foram complicações pós-cirúrgicas e mortalidade na unidade de terapia intensiva e 90 dias após a cirurgia. RESULTADOS: Cirurgias de grande porte e de urgência foram realizadas em 66,4 por cento e 31,7 por cento, dos pacientes, respectivamente. A taxa de mortalidade na unidade de terapia intensiva foi de 15 por cento, e 38 por cento dos pacientes tiveram complicações no pós-operatório. A complicação mais comum foi infecção ou sepse (24,7 por cento). Isquemia miocárdica foi diagnosticada em apenas 1,9 por cento. Um total de 94 por cento dos pacientes que morreram após a cirurgia tinha co-morbidades associadas (3,4 ± 2,2). A principal causa de óbito foi disfunção de múltiplos órgãos (53 por cento). CONCLUSÃO: Sepse é a causa predominante de morbidade em pacientes submetidos a cirurgias não cardíacas. A grande maioria dos óbitos no pós-operatório ocorreu por disfunção de múltiplos órgãos.

OBJECTIVES: Due to the dramatic medical breakthroughs and an increasingly ageing population, the proportion of patients who are at risk of dying following surgery is increasing over time. The aim of this study was to evaluate the outcomes and the epidemiology of non-cardiac surgical patients admitted to the intensive care unit. METHODS: A multicenter, prospective, observational, cohort study was carried out in 21 intensive care units. A total of 885 adult surgical patients admitted to a participating intensive care unit from April to June 2006 were evaluated and 587 patients were enrolled. Exclusion criteria were trauma, cardiac, neurological, gynecologic, obstetric and palliative surgeries. The main outcome measures were postoperative complications and intensive care unit and 90-day mortality rates. RESULTS: Major and urgent surgeries were performed in 66.4 percent and 31.7 percent of the patients, respectively. The intensive care unit mortality rate was 15 percent, and 38 percent of the patients had postoperative complications. The most common complication was infection or sepsis (24.7 percent). Myocardial ischemia was diagnosed in only 1.9 percent of the patients. A total of 94 percent of the patients who died after surgery had co-morbidities at the time of surgery (3.4 ± 2.2). Multiple organ failure was the main cause of death (53 percent). CONCLUSION: Sepsis is the predominant cause of morbidity in patients undergoing non-cardiac surgery. In this patient population, multiple organ failure prevailed as the most frequent cause of death in the hospital.

Epidemiology and outcomes of non-cardiac surgical patients in Brazilian intensive care units. / Epidemiologia e desfecho de pacientes cirúrgicos não cardíacos em unidades de terapia intensiva no Brasil.

OBJECTIVES: Due to the dramatic medical breakthroughs and an increasingly ageing population, the proportion of patients who are at risk of dying following surgery is increasing over time. The aim of this study was to evaluate the outcomes and the epidemiology of non-cardiac surgical patients admitted to the intensive care unit. METHODS: A multicenter, prospective, observational, cohort study was carried out in 21 intensive care units. A total of 885 adult surgical patients admitted to a participating intensive care unit from April to June 2006 were evaluated and 587 patients were enrolled. Exclusion criteria were trauma, cardiac, neurological, gynecologic, obstetric and palliative surgeries. The main outcome measures were postoperative complications and intensive care unit and 90-day mortality rates. RESULTS: Major and urgent surgeries were performed in 66.4% and 31.7% of the patients, respectively. The intensive care unit mortality rate was 15%, and 38% of the patients had postoperative complications. The most common complication was infection or sepsis (24.7%). Myocardial ischemia was diagnosed in only 1.9% of the patients. A total of 94 % of the patients who died after surgery had co-morbidities at the time of surgery (3.4 ± 2.2). Multiple organ failure was the main cause of death (53%). CONCLUSION: Sepsis is the predominant cause of morbidity in patients undergoing non-cardiac surgery. In this patient population, multiple organ failure prevailed as the most frequent cause of death in the hospital.

[New prognostic and predictive factors in advanced colorectal cancer]. / Nuevos factores pronósticos y predictivos en el cáncer colorrectal avanzado.

Cancer patients often show a clinical tendency to thromboembolic events. This tendency is due to tumor cell-related factors together with the damage of the vascular endothelial exerted by chemotherapy treatment. Gastrointestinal tumors especially contribute to these types of events. More recently, the implication of tumor angiogenesis in clotting/fibrynolisys and plasminogen systems activation has been addressed in cancer patients. Finally, some hemostasis and angiogenesis-related factors such as platelets, von Willebrand factor, fibrinogen, plasminogen activator inhibitor type-1, D dimer, and vascular endotelial growth factor have been highlighted as new potential response and survival predictors in colorectal cancer patients. In this review article, the current evidence supporting the use of these proteins in assessing prognosis in colorectal cancer patients is critically exposed and discussed.