Migrating Platelets Are Mechano-scavengers that Collect and Bundle Bacteria.

Blood platelets are critical for hemostasis and thrombosis and play diverse roles during immune responses. Despite these versatile tasks in mammalian biology, their skills on a cellular level are deemed limited, mainly consisting in rolling, adhesion, and aggregate formation. Here, we identify an unappreciated asset of platelets and show that adherent platelets use adhesion receptors to mechanically probe the adhesive substrate in their local microenvironment. When actomyosin-dependent traction forces overcome substrate resistance, platelets migrate and pile up the adhesive substrate together with any bound particulate material. They use this ability to act as cellular scavengers, scanning the vascular surface for potential invaders and collecting deposited bacteria. Microbe collection by migrating platelets boosts the activity of professional phagocytes, exacerbating inflammatory tissue injury in sepsis. This assigns platelets a central role in innate immune responses and identifies them as potential targets to dampen inflammatory tissue damage in clinical scenarios of severe systemic infection.

The Importance of Lumbar Lordosis During Laparoscopic Trocar Entry.

STUDY OBJECTIVE: Investigating the effect of lumbar lordosis on the relationship between abdominal trocar entry points and major vascular structures. DESIGN: Retrospective cohort. SETTING: Tertiary referral center. PATIENTS: Distances between the skin and the aorta and inferior vena cava at the trocar entry points, both at the umbilicus and 3 cm and 5 cm superior to the umbilicus, were measured at entry angles of 90 and 45 degrees in 101 abdominal computer tomography images. INTERVENTIONS: The relationship of these values with lumbar lordosis was investigated concerning menopausal status, body mass index (BMI), and parity differences. To assess the isolated effect of lumbar lordosis, a simulated 30-degree increase in the lordosis angle was applied to the patients' computed tomography images. The impact of this increased lumbar lordosis angle on the distances between the skin and major vessels was then evaluated at both the umbilical and supraumbilical trocar entry sites. MEASUREMENTS AND MAIN RESULTS: In the tomographic images of all patients, the distances from the skin to vascular structures were measured at a 90-degree entry angle, resulting in measurements of 8.97 cm ± 2.81 at the umbilicus, 10.89 cm ± 3.02 at 3 cm above the umbilicus, and 11.36 cm ± 2.88 at 5 cm above the umbilicus. These distances exhibited significant differences between patients with BMI <30 and BMI ≥30, as well as between premenopausal and postmenopausal patients. However, at a 45-degree entry angle, vascular structures were observed in only a few patients during trocar projection, and no measurable values were determined. In the simulation, it was found that a 1-degree increase in lumbar lordosis angle resulted in a decrease of 0.272 mm ± 0.018 in the distance between the skin and vascular structures at the umbilicus, 0.425 mm ± 0.024 at 3 cm above the umbilicus, and 0.428 mm ± 0.024 at 5 cm above the umbilicus. CONCLUSION: An increase in the degree of lumbar lordosis reduces the distance between trocar entry points and major vascular structures. Along with other factors during Veress and trocar entry, lumbar lordosis should be carefully considered.

Hemostasis vs. homeostasis: Platelets are essential for preserving vascular barrier function in the absence of injury or inflammation.

Platelets are best known for their vasoprotective responses to injury and inflammation. Here, we have asked whether they also support vascular integrity when neither injury nor inflammation is present. Changes in vascular barrier function in dermal and meningeal vessels were measured in real time in mouse models using the differential extravasation of fluorescent tracers as a biomarker. Severe thrombocytopenia produced by two distinct methods caused increased extravasation of 40-kDa dextran from capillaries and postcapillary venules but had no effect on extravasation of 70-kDa dextran or albumin. This reduction in barrier function required more than 4 h to emerge after thrombocytopenia was established, reverting to normal as the platelet count recovered. Barrier dysfunction was also observed in mice that lacked platelet-dense granules, dense granule secretion machinery, glycoprotein (GP) VI, or the GPVI signaling effector phospholipase C (PLC) γ2. It did not occur in mice lacking α-granules, C type lectin receptor-2 (CLEC-2), or protease activated receptor 4 (PAR4). Notably, although both meningeal and dermal vessels were affected, intracerebral vessels, which are known for their tighter junctions between endothelial cells, were not. Collectively, these observations 1) highlight a role for platelets in maintaining vascular homeostasis in the absence of injury or inflammation, 2) provide a sensitive biomarker for detecting changes in platelet-dependent barrier function, 3) identify which platelet processes are required, and 4) suggest that the absence of competent platelets causes changes in the vessel wall itself, accounting for the time required for dysfunction to emerge.

Learning from mistakes when reporting urgent and emergency vascular studies.

The majority of out-of-hours cases relate to neurological, chest, and gastrointestinal pathologies with acute vascular cases being encountered less commonly. Trainees and exposure of non-vascular/interventional radiology (IR) consultants to angiographic imaging is often limited in working hours and this may lead to reporting on-call cases outside of normal daytime practice. In a recent local review, a number on-call vascular studies were found to contain a number of vascular-related discrepancies. Vascular reporting is a complex subspecialty, which comprises many clear diagnoses (large vessel occlusions, large vessel aneurysms, or dissections); however, also several subtle and complex abnormalities. These more subtle abnormalities, at times, require dedicated vascular specialist review to ensure subtle findings are communicated appropriately to the clinical team. The recent increased complexity of endovascular treatments and their complications has also provided further challenge for the non-specialist reporter. Similarly, improved imaging techniques have allowed for non-obvious but significant findings that may require urgent management, such as small aneurysms and dissection flaps. We will review a range of key vascular findings that demonstrate learning opportunities, particularly within the acute and on-call settings. These will include gastrointestinal haemorrhage, subtle aortic pathologies, head and neck vascular emergencies, small to mid-sized vessel injuries and imaging of post-procedural complications. Educational hints and tips will be provided to enable learning from mistakes encountered by trainees and non-vascular specialist radiologists in the on-call or urgent reporting settings, and these will be reviewed with reference to the literature.

Retroperitoneal teratomas in children: a single institution experience.

PURPOSE: Retroperitoneal teratomas (RPTs) are rare in infants. We report our experience of treating pediatric patients with RPTs over many years at a single institution, with the aim of developing a safe and secure operative strategy for RPTs in infants. METHODS: We reviewed the medical records of patients who underwent treatment for RPTs in our institution between April, 1984 and December, 2017, to analyze their background and clinical data. The diagnosis of RPT was confirmed histologically in all patients. RESULTS: The subjects of this retrospective analysis were 14 pediatric patients (female, n = 11; male, n = 4), ranging in age from 6 days to 12 years, 11 (73.3%) of whom were under 1 year of age. Complete surgical resection was performed in all patients. The tumor ruptured during surgery in four (26.7%) patients and perioperative vessel injuries occurred in six (40.0%) patients, resulting in nephrectomy in one (6.7%). Three (20.0%) patients suffered unilateral renal dysfunction as a surgical complication. Only one patient received postoperative chemotherapy. All patients were free of disease at the time of writing. CONCLUSION: Perioperative complications are not uncommon during surgery for RPTs, despite their benign nature. Preoperative imaging evaluation is important and operative management may be challenging. Because of the favorable prognosis and the frequency of adverse events in surgery, partial resection or split excision is sometimes unavoidable. Meticulous follow-up for recurrence is required for such patients.

Efficacy and Safety of Plastic Cannulae Compared with Metal Needles in the Initial Use of an Arteriovenous Fistulae in Incident Hemodialysis Patients: A Randomized Controlled Study.

INTRODUCTION: Successful cannulation of an arteriovenous fistula (AVF) is important in patients starting hemodialysis (HD). Metal needles have been used for decades, but the usefulness of plastic cannulae has recently been demonstrated as a new technique. METHODS: This was a prospective, randomized, open-label study of incident HD patients. Eligible patients were randomized into 2 groups in a 1:1 ratio (n = 45/group). Maturation of the AVF was confirmed using Doppler ultrasound prior to first needling, and 2 well-trained nurses implemented the AVF cannulation. The primary endpoint was the initial cannulation failure rate, defined as the failure of successful completion of 3 consecutive dialysis sessions. The secondary endpoints were time for hemostasis at the end of HD, degree of patients' pain, degree of cannulation difficulty felt by the nursing staffs, and achieving optimal HD adequacy. RESULTS: The mean elapsed time from AVF creation to the first cannulation was 48.1 ± 16.7 days. A total of 17 cases of cannulation failure occurred, and the failure risk tended to be higher in the metal needle group than the plastic cannula group (hazard ratio 2.6, 95% confidence interval 0.95-7.41) after adjusting for age, gender, comorbidities, and AVF location. The overall incidence of vessel injury was higher and time for hemostasis was significantly longer in the metal group than the plastic group. The use of plastic cannula was associated with a better HD adequacy compared to a metal needle. However, the patients' pain score (p = 0.004) and nursing staff's cannulation difficulty score (p = 0.084) were higher in the plastic group, emphasizing the great importance of practice using plastic cannulae. CONCLUSION: The vascular outcomes of plastic cannulae were much favorable compared to metal needles in incident HD patients. The use of plastic cannulae could be a new and innovative way to improve the quality of dialysis.

Computer Simulation of Platelet Adhesion around Stent Struts in the Presence and Absence of Tissue Defects around Them.

AIM: To predict platelet accumulation around stent struts in the presence or absence of tissue defects around them. METHODS: Computer simulations were performed using virtual platelets implementing the function of the three membrane proteins: glycoprotein (GP) Ibα, GPIIb/IIIa, and GPVI. These platelets were perfused around the stent struts implanted into the vessel wall in the presence or absence of tissue defects around them using within the simulation platform. The number of platelets that adhered around stent struts was calculated by solving the blood flow using Navier-Stokes equation along with the adhesion of membrane protein modeled within the platform. RESULTS: Platelet accumulation around stent struts occurred mostly at the downstream region of the stent strut array. The majority of platelets adhered at the downstream of the first bend regardless of the tissue defect status. Platelet adhesion around stent struts occurred more rapidly in the presence of tissue defects. CONCLUSION: Computer simulation using virtual platelets suggested a higher rate of platelet adhesion in the presence of tissue defects around stent struts.

Modeling Clot Formation of Shear-Injured Platelets in Flow by a Dissipative Particle Dynamics Method.

The regions with high non-physiological shear stresses (NPSS) are inevitable in blood-contacting medical devices (BCMDs) used for mechanically assisted circulatory support. NPSS can cause platelet activation and receptor shedding potentially resulting in the alteration of hemostatic function. In this study, we developed a dissipative particle dynamics model to characterize clot formation (platelet-collagen and inter-platelet adhesion) of NPSS-traumatized blood at a vascular injury site. A rectangular tube of 50 × 50 × 200 µm with an 8 × 8 µm collagen-coated area was modeled as a small blood vessel and perfusion with blood. Clot formation dynamics during perfusion was simulated. NPSS-traumatized blood was modeled to have more activated platelet and fewer adhesion receptors with weakened inter-platelet binding. Computational results showed that clots grew at a faster rate while the structure of the clots was less stable and collapsed more frequently for NPSS-traumatized blood compared with normal blood. The finding that NPSS-traumatized platelets could result in quicker but more easily breakable blood clots at injury sites may explain why increased risks of thrombotic and bleeding complications occurred concurrently in patients implanted with BCMDs.

MicroRNA-129-1-3p regulates cyclic stretch-induced endothelial progenitor cell differentiation by targeting Runx2.

Endothelial progenitor cells (EPCs) are vital to the recovery of endothelial function and maintenance of vascular homeostasis. EPCs mobilize to sites of vessel injury and differentiate into mature endothelial cells (ECs). Locally mobilized EPCs are exposed to cyclic stretch caused by blood flow, which is important for EPC differentiation. MicroRNAs (miRNAs) have emerged as key regulators of several cellular processes. However, the role of miRNAs in cyclic stretch-induced EPC differentiation remains unclear. Here, we investigate the effects of microRNA-129-1-3p (miR-129-1-3p) and its novel target Runt-related transcription factor 2 (Runx2) on EPC differentiation induced by cyclic stretch. Bone marrow-derived EPCs were exposed to cyclic stretch with a magnitude of 5% (which mimics physiological mechanical stress) at a constant frequency of 1.25 Hz for 24 hours. The results from a miRNA array revealed that cyclic stretch significantly decreased miR-129-1-3p expression. Furthermore, we found that downregulation of miR-129-1-3p during cyclic stretch-induced EPC differentiation toward ECs. Meanwhile, expression of Runx2, a putative target gene of miR-129-1-3p, was increased as a result of cyclic stretch. A 3'UTR reporter assay validated Runx2 as a direct target of miR-129-1-3p. Furthermore, small interfering RNA (siRNA)-mediated knockdown of Runx2 inhibited EPC differentiation into ECs and attenuated EPC tube formation via modulation of vascular endothelial growth factor (VEGF) secretion from EPCs in vitro. Our findings demonstrated that cyclic stretch suppresses miR-129-1-3p expression, which in turn activates Runx2 and VEGF to promote endothelial differentiation of EPCs and angiogenesis. Therefore, targeting miR-129-1-3p and Runx2 may be a potential therapeutic strategy for treating vessel injury.

Paeoniflorin attenuates oxidized low-density lipoprotein-induced apoptosis and adhesion molecule expression by autophagy enhancement in human umbilical vein endothelial cells.

Oxidized low-density lipoprotein (ox-LDL)-induced endothelial dysfunction is recognized as a driving force in the development of atherosclerosis (AS). Paeoniflorin (Pae), a typical traditional herbal medicine, possesses anti-inflammatory, antioxidative, antihyperglycaemic, and antiapoptotic properties. Our study aimed to investigate the effects of Pae on ox-LDL-induced injury of the human umbilical vein endothelial cells (HUVECs) and to explore its molecular mechanism. We found that ox-LDL stimulation inhibited cell viability, activated autophagy, and induced apoptosis and adhesion molecule expression in HUVECs. Pae rescued ox-LDL-induced viability reduction and enhanced the ox-LDL-induced autophagy activation in HUVECs. Pae inhibited ox-LDL-induced apoptosis and adhesion molecule expression by autophagy enhancement in HUVECs. In addition, inhibition of SIRT1 by EX-527 abolished the promoting effect of Pae on autophagy and restored the inhibitory effect of Pae on apoptosis and adhesion molecule expression in the presence of ox-LDL. In conclusion, Pae attenuated ox-LDL-induced apoptosis and adhesion molecule expression by autophagy enhancement via upregulation of SIRT1 in HUVECs, shedding light on the mechanism underlying the protective effect of Pae on ox-LDL-induced injury of HUVECs.

Laparoscopic entry techniques.

BACKGROUND: Laparoscopy is a common procedure in many surgical specialties. Complications arising from laparoscopy are often related to initial entry into the abdomen. Life-threatening complications include injury to viscera (e.g. bowel, bladder) or to vasculature (e.g. major abdominal and anterior abdominal wall vessels). No clear consensus has been reached as to the optimal method of laparoscopic entry into the peritoneal cavity. OBJECTIVES: To evaluate the benefits and risks of different laparoscopic entry techniques in gynaecological and non-gynaecological surgery. SEARCH METHODS: We searched the Cochrane Gynaecology and Fertility (CGF) Group trials register, CENTRAL, MEDLINE, Embase, PsycINFO, and trials registers in January 2018. We also checked the references of articles retrieved. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that compared one laparoscopic entry technique versus another. Primary outcomes were major complications including mortality, vascular injury of major vessels and abdominal wall vessels, visceral injury of bladder or bowel, gas embolism, solid organ injury, and failed entry (inability to access the peritoneal cavity). Secondary outcomes were extraperitoneal insufflation, trocar site bleeding, trocar site infection, incisional hernia, omentum injury, and uterine bleeding. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed risk of bias, and extracted data. We expressed findings as Peto odds ratios (Peto ORs) with 95% confidence intervals (CIs). We assessed statistical heterogeneity using the I² statistic. We assessed the overall quality of evidence for the main comparisons using GRADE methods. MAIN RESULTS: The review included 57 RCTs including four multi-arm trials, with a total of 9865 participants, and evaluated 25 different laparoscopic entry techniques. Most studies selected low-risk patients, and many studies excluded patients with high body mass index (BMI) and previous abdominal surgery. Researchers did not find evidence of differences in major vascular or visceral complications, as would be anticipated given that event rates were very low and sample sizes were far too small to identify plausible differences in rare but serious adverse events.Open-entry versus closed-entryTen RCTs investigating Veress needle entry reported vascular injury as an outcome. There was a total of 1086 participants and 10 events of vascular injury were reported. Four RCTs looking at open entry technique reported vascular injury as an outcome. There was a total of 376 participants and 0 events of vascular injury were reported. This was not a direct comparison. In the direct comparison of Veress needle and Open-entry technique, there was insufficient evidence to determine whether there was a difference in rates of vascular injury (Peto OR 0.14, 95% CI 0.00 to 6.82; 4 RCTs; n = 915; I² = N/A, very low-quality evidence). Evidence was insufficient to show whether there were differences between groups for visceral injury (Peto OR 0.61, 95% CI 0.06 to 6.08; 4 RCTs; n = 915: I² = 0%; very low-quality evidence), or failed entry (Peto OR 0.45, 95% CI 0.14 to 1.42; 3 RCTs; n = 865; I² = 63%; very low-quality evidence). Two studies reported mortality with no events in either group. No studies reported gas embolism or solid organ injury.Direct trocar versus Veress needle entryTrial results show a reduction in failed entry into the abdomen with the use of a direct trocar in comparison with Veress needle entry (OR 0.24, 95% CI 0.17 to 0.34; 8 RCTs; N = 3185; I² = 45%; moderate-quality evidence). Evidence was insufficient to show whether there were differences between groups in rates of vascular injury (Peto OR 0.59, 95% CI 0.18 to 1.96; 6 RCTs; n = 1603; I² = 75%; very low-quality evidence), visceral injury (Peto OR 2.02, 95% CI 0.21 to 19.42; 5 RCTs; n = 1519; I² = 25%; very low-quality evidence), or solid organ injury (Peto OR 0.58, 95% Cl 0.06 to 5.65; 3 RCTs; n = 1079; I² = 61%; very low-quality evidence). Four studies reported mortality with no events in either group. Two studies reported gas embolism, with no events in either group.Direct vision entry versus Veress needle entryEvidence was insufficient to show whether there were differences between groups in rates of vascular injury (Peto OR 0.39, 95% CI 0.05 to 2.85; 1 RCT; n = 186; very low-quality evidence) or visceral injury (Peto OR 0.15, 95% CI 0.01 to 2.34; 2 RCTs; n = 380; I² = N/A; very low-quality evidence). Trials did not report our other primary outcomes.Direct vision entry versus open entryEvidence was insufficient to show whether there were differences between groups in rates of visceral injury (Peto OR 0.13, 95% CI 0.00 to 6.50; 2 RCTs; n = 392; I² = N/A; very low-quality evidence), solid organ injury (Peto OR 6.16, 95% CI 0.12 to 316.67; 1 RCT; n = 60; very low-quality evidence), or failed entry (Peto OR 0.40, 95% CI 0.04 to 4.09; 1 RCT; n = 60; very low-quality evidence). Two studies reported vascular injury with no events in either arm. Trials did not report our other primary outcomes.Radially expanding (STEP) trocars versus non-expanding trocarsEvidence was insufficient to show whether there were differences between groups in rates of vascular injury (Peto OR 0.24, 95% Cl 0.05 to 1.21; 2 RCTs; n = 331; I² = 0%; very low-quality evidence), visceral injury (Peto OR 0.13, 95% CI 0.00 to 6.37; 2 RCTs; n = 331; very low-quality evidence), or solid organ injury (Peto OR 1.05, 95% CI 0.07 to 16.91; 1 RCT; n = 244; very low-quality evidence). Trials did not report our other primary outcomes.Other studies compared a wide variety of other laparoscopic entry techniques, but all evidence was of very low quality and evidence was insufficient to support the use of one technique over another. AUTHORS' CONCLUSIONS: Overall, evidence was insufficient to support the use of one laparoscopic entry technique over another. Researchers noted an advantage of direct trocar entry over Veress needle entry for failed entry. Most evidence was of very low quality; the main limitations were imprecision (due to small sample sizes and very low event rates) and risk of bias associated with poor reporting of study methods.

Protection of Inferior Alveolar Neurovascular Bundle in Alveolar Bone Operation.

PURPOSE: The aim of this study was to investigate the protection of the inferior alveolar neurovascular bundle in alveolar bone operation in conditions such as chronic osteomyelitis and cementoma. PATIENTS AND METHODS: The study enrolled 7 cases, 4 with chronic osteomyelitis and 3 with cementoma with pain. Computed tomography scan and 3-dimensional reconstruction were performed for the diseases. Data were processed by ProPlan CMF 1.3 software. The edge of lesion was defined and the inferior alveolar nerve was marked. Template was designed to guide the osteotomy line. Piezosurgery was used for osteotomy, with the avoidance of nerve canal. Current perception threshold (CPT) was performed to evaluate the nerve function after operation. RESULTS: The CPT difference of the affected side before and after operation showed no statistically significant differences compared with that of the unaffected side (P = 0.0556). CONCLUSIONS: Digital template protects the inferior alveolar neurovascular bundle with the aid of piezosurgery during alveolar bone resection, which obtained satisfying clinical results. As powerful assistive tools of functional surgery, digital template and piezosurgery achieve both the purposes of treatment and function.

The spectrum of injuries in buttock stab wounds.

Buttock stab wounds are a surprisingly common and increasing source of presentations to emergency departments. These injuries can have a significant impact on quality of life, and there are a number of often subtle, but significant, injuries that the radiologist must be alert to when interpreting computed tomography examinations in these patients. In this review, we will examine briefly the sociological reasons for the increase in these injuries, discuss appropriate imaging techniques, and provide imaging examples of the clinically important injuries that may be encountered in this region. These injuries include rectal or colonic perforation; genito-urinary trauma, for example urethral injury; injury to the sciatic nerve; and a spectrum of vascular trauma including transection and pseudoaneurysm or arteriovenous fistula formation.

Thrombosis and von Willebrand Factor.

One of the key players in both hemostasis and thrombosis is von Willebrand factor (vWF), which demonstrates a duality between these two processes. Thrombus is structured by numerous elements, including endothelial cells, platelets, plasma proteins and shear stress alteration. In circulation, once a vessel wall is injured, collagen is exposed and platelets attach to the site of injury. Accordingly, vWF mediates adherence of platelets to the damaged vessel wall by binding both to the collagen and platelet receptor. A growing body of data also indicates a role for neutrophil extracellular traps (NETs) in human thrombosis as scaffolds for vWF, promoting thrombosis. VWF also mediates the protection of factor VIII, a main cofactor of the intrinsic clotting pathway. Since vWF plays a critical role in both thrombotic and bleeding events, a decreased plasma level of this factor may point to a bleeding disorder, while an elevated plasma level may predict occurrence of thrombosis. Since thrombotic events are the foremost cause of death, inhibiting the vWF activity would be a novel prophylaxis to reduce these events. Though, accumulated data have made vWF a promising focus for research on cardiovascular diseases (CVD). This chapter, however, aims to clarify the role of vWF in thrombus formation and pathogenesis of thrombosis.

The influence of epidural catheter on the incidence of intravascular injection during caudal block.

OBJECTIVE: The aim of this study was to analyze the influence of epidural catheters on the incidence of intravascular injection and to identify possible predictors of intravascular injection in patients undergoing a caudal block using fluoroscopy. METHODS: A total of 154 patients scheduled to receive a caudal block were randomized into group N (those without epidural catheter) or group C (those with epidural catheter). Demographic and clinical data were recorded and analyzed. RESULTS: The incidence of intravascular injection was 15.6% in group N, 6.5% in group C, and 11.0% overall, without statistical differences between the two groups (P = 0.105). Univariate analysis revealed that blood at hub (P = 0.047) and positive aspiration test (P = 0.045) were more frequently observed in group N than in group C. Quality of analgesia was significantly higher in group C than in group N (P = 0.029). Multivariate analysis identified older age (P = 0.024), blood at hub (P = 0.003), and positive aspiration test (P = 0.001) as predictors of intravascular injection. CONCLUSIONS: In this study, while the incidence of intravascular injection during caudal blocks was less frequent with epidural catheter use, it was not statistically significant. However, a caudal block using an epidural catheter provided a lower incidence of blood at hub, fewer positive aspiration tests, and superiority in pain improvement.

[Large hematoma - early postoperative complication after the transobturator tape procedure]. / Rozsáhlý hematom - casná komplikace po antiinkontinentní operaci transobturátorovým prístupem.

OBJECTIVE: To present a case report of the occurrence of large hematoma after the transobturator tape procedure. DESIGN: Case report. SETTING: Department of Obstetrics and Gynecology, University Hospital Ostrava. CONCLUSION: The risk of vessel injury during the transobturator procedure is rare, but it is possible. The surgeons should be aware of the possibility and know possible solution. Conservative management of hematomas has been recommended when the patient is hemodynamically stable only without other secondary complications.

MSCs: The Sentinel and Safe-Guards of Injury.

Mesenchymal stem cells (MSCs) were originally named because they could differentiate in a variety of mesenchymal phenotypes in culture. Evidence indicates that MSCs arise from perivascular cells, pericytes, when the blood vessels are broken or inflamed. These pericyte/MSCs are situated on every blood vessel in the body. The MSCs sense the micro-environment of the injury site and secrete site-specific factors that serve several important reparative functions: first, a curtain of molecules from the front of the MSCs provide a barrier from the interrogation of the over-aggressive immune system. Second, from the back of the MSCs, a different set of bioactive agents inhibit scar formation and establish a regenerative micro-environment. Third, if bacteria are sensed by the MSCs, they produce powerful protein antibiotics that kill the bacteria on contact. Last, the MSCs surround and encyst intruding solid objects like a piece of wood (a "splinter") or other foreign objects. The MSCs act as a combination paramedic and emergency room (ER) staff to survey the damage, isolate foreign components, stabilize the injured tissues, provide antibiotics and encysting protection before a slower, medicinal sequence can be initiated to regenerate the damaged tissue. The MSCs, thus, act as sentinels to safeguard the individual from intrusion and chronic injury. A societal treatment system has evolved, paramedics and ER procedures, which mirror in a macro-sense what MSCs orchestrate in a micro-sense. Key to this new understanding is that MSCs are not "stem cells," but rather as Medicinal Signaling Cells as the therapeutic agents.

Protection against vascular leak in neprilysin transgenic mice with complex overexpression pattern.

Neprilysin (NEP) is a cell surface metallopeptidase found in many tissues. Based mostly on pharmacological manipulations, NEP has been thought to protect blood vessels from plasma extravasation. We have suggested that NEP may protect against pulmonary vascular injury. However, these prior studies did not utilize mice which overexpress NEP. The aims of the present investigation were to develop and characterize doubly transgenic (DT) mice that overexpress NEP universally and conditionally, and to investigate the protective effect that overexpressed NEP may have against plasma extravasation in the vasculature. The duodenum, which is often used to assess vascular permeability, and in which the NEP protein was overexpressed in our DT mice two-fold, was selected as our experimental preparation. We found that substance P-induced plasma extravasation was decreased substantially (3.5-fold) in the duodenums of our doxycycline-treated DT mice, giving independent evidence of NEP's protective effects against plasma extravasation. Transgenic lung NEP protein was not stably expressed in the DT mice, so we were not able to test the effect of NEP overexpression in the lung. Although initially overexpressed nearly nine-fold at that site, pulmonary NEP protein overexpression eventually dissipated. Surprisingly, at a time when there was no lung transgenic NEP protein overexpression, lung NEP mRNA expression was still increased 23-fold, indicating that the expression defect probably is not transcriptional. These studies help to characterize our complex transgenic model of NEP overexpression and further demonstrate NEP's protective effects against plasma extravasation.

Laparoscopic Hysterectomy for Uterine Fibroids: Is it Safe?

As more complex cases and larger uterine specimens are able to be managed with minimally invasive surgery, the limitations of tissue retrieval with these methods are of increasing concern. Risks of morcellator-related injury, tissue dissemination, or fragmentation must be weighed against increased morbidity of abdominal approach to hysterectomy. In an effort to mitigate the risks of tissue morcellation, containment system use must be considered when fragmenting a specimen, either with power morcellation or a manual technique via the vagina or minilaparotomy.