Compression Of Vessels Research Articles

Gut Microbiota Was Involved in the Process of Liver Injury During Intra-Abdominal Hypertension.

Background: Intestinal damage caused by intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) can lead to the ectopic gut microbiota, which can contribute to liver injury via portal veins. Therefore, it is speculated that gut microbiota disorder caused by IAH/ACS may result in liver injury. The relationship between gut microbiota and IAH/ACS-related liver injury was investigated in this study.Methods: A model of IAH was established in rats, and 16S rRNA sequencing was analyzed for gut microbiota in the feces of rats. The elimination of gut microbiota was completed by antibiotics gavage, and fecal microbiota transplantation (FMT) was used to change the composition of gut microbiota in rats.Results: In addition to the traditional cause of liver blood vessel compression, liver injury caused by IAH was also associated with gut microbiota dysbiosis. Gut microbiota clearance can relieve liver injury caused by IAH, while FMT from IAH-intervened rats can aggravate IAH-related liver injury.Conclusion: The gut microbiota was one of the most important factors contributing to the IAH-related liver injury, and the JNK/p38 signaling pathway was activated in this process.

364 Pulmonary hypertension: survival and prognostic factors by subgroups

Abstract Aims The definition of pulmonary hypertension (PH) requires the documentation of mean pulmonary arterial pressure (PAPm) ≥20 mmHg at rest, assessed by right cardiac catheterization. This condition can characterize multiple clinical conditions with different pathophysiological and haemodynamic aspects. Specifically, in pulmonary arterial hypertension (IAP) (Group 1), the increase in PAP is due to an intrinsic pathology of the pulmonary microcirculation; Group 2 includes the forms of IP associated with a pathology of the left heart; Group 3 includes all pathologies of the pulmonary parenchyma and/or hypoxic conditions that lead to a secondary impairment of the small circulation; Group 4 identifies patients with chronic thromboembolic pulmonary heart (CPCTE); finally, Group 5 includes rare clinical conditions in which IP is linked to direct involvement or ab extrinsic compression of the pulmonary vessels. Methods and results To examine the number of deaths and the differences between the various subgroups, we analyzed the follow-up of approximately 76 patients (64.30 ± 13.20 years, 37% male) enrolled in the Pulmonary Hypertension Clinic of the San Giovanni AOU Dio and Ruggi d’Aragona of Salerno from 2014 to 2020 excluding patients with IP under definition and those ‘screened’ who did not show pulmonary hypertension at rest. At each visit, the patients were subjected to anamnestic data collection, physical examination, measurement of blood pressure, heart rate, arterial saturation, transthoracic cardiac echo color Doppler at rest, attribution of the functional class NYHA, evaluation of functional capacity by performing the test of the 6-min walk test (6MWT) and possible programming of right cardiac catheterization. From the data analysis it was found that 26 patients (34.21%, 55.81 ± 13.90 years, 27% males) were affected by IP group 1; 15 patients (19.48%, 74.12 ± 6.26 years, 20% male) were affected by IP group 2; 14 patients (18.18%, 63.34 ± 11.52 years, 71% male) were affected by IP group 3; 12 patients (15.58%, 67.22 ± 11.53 years, 33% male) were affected by IP group 4; 2 patients (2.60%, 71.57 ± 12.48 years, 0% male) were affected by IP group 5; 7 patients (9.09%, 70.07 ± 8.27 years, 57% male) were affected by group 2–3 mixed IP. Analysing the number of deaths, of the 76 patients, 17 deaths were recorded in total (22.37%). All patients in group 1 had been treated with specific therapy and survival was 88% at 3 years. Of the three deaths (12%) in this group, one patient had idiopathic PAH non-responder to pulmonary vasoreactivity test, one patient belonged to the IAP subgroup associated with congenital heart shunt but with concomitant lung disease, and the third patient belonged to the IAP subgroup associated with connective tissue disease (specifically Takayasu’s arteritis). From the analysis of the idiopathic IAP subgroup it emerged that the patients were all women, with an average age of 50.81 ± 3.98 years, and that the deceased patient was distinguished at the first visit from the other patients for: a history of arterial hypertension, dysthyroidism, and obesity; worst NYHA class (III vs. II), elevated heart rate (102 vs. 70.00 ± 7.07 b.p.m.) and blood pressure (SBP: 150.00 vs. 127.50 ± 10.61; DBP 90.00 vs. 75.00 ± 7.07 mmHg) at rest at the clinic visit. Transthoracic echocardiography revealed elevated PAPs values (100.00 vs. 42.50 ± 20.51 mmHg), low TAPSE values (20.00 vs. 26.50 ± 3.54 mm), reduced pulmonary acceleration time (ACT 60 ms), enlargement of the right atrium (area 22 cm2), worst exercise tolerance parameters (6MWT 300 m and 86% final SO2 vs. 427.50 ± 74.25 m and 96.50 ± 0.71% final SO2). Conclusions The percentage of deaths in the different groups appears very heterogeneous, especially if we consider the six deaths (42.86%) in group 3 and three deaths (42.86%) in patients with mixed IP groups 2 and 3. In these two groups, age and advanced NYHA class were the most representative prognostic factors. On the other hand, analysing patients belonging to the idiopathic IAP subgroup, a worse prognosis is entrusted to the negativity of the vasoreactivity test, to the presence of cardiovascular comorbidities (arterial hypertension and dysthyroidism in our case), to worse echocardiographic values (PAPs, TAPSE, ACT, atrial area right) and reduced functional capacity at the 6MWT. However, early treatment and innovative drugs together with a careful strategy have been allowed.

Decreasing hyaluronic acid combined with drug-loaded nanoprobes improve the delivery and efficacy of chemotherapeutic drugs for pancreatic cancer.

Pancreatic cancer is one of the common malignant tumors of the digestive system, and its clinical treatment is still very challenging. Most of the pancreatic cancer chemotherapeutic drugs have poor plasma stability, low cell uptake efficiency, and are prone to developing drug resistance and toxic side effects. Besides, pancreatic cancer often has a dense extracellular matrix, which consists of collagens, hyaluronic acid, and other proteoglycans. Among them, hyaluronic acid is a key component of the dense matrix, which results in vascular compression and insufficient perfusion, and hinders the delivery of chemotherapeutic drugs. In this study, we explore using hyaluronidase in tumor-bearing mice to eliminate the hyaluronic acid barrier, to reduce blood vessel compression and reshape the tumor microenvironment. In addition, we evaluate using doxorubicin-loaded nanoprobes to improve the stability and local tumor-killing effect of the drug. The nanoprobes have the characteristics of near-infrared optical imaging, which are used to monitor the tumor size in real-time during the treatment process, and dynamically observe the tumor inhibitory effect. The results show that elimination of the hyaluronic acid barrier combined with the doxorubicin-loaded nanoprobes can greatly increase drug penetration into tumor tissue and improve the effectiveness of chemotherapy drugs. This study provides a novel strategy for the treatment of pancreatic cancer.

Аngiogenesis in Uveal Melanoma

Uveal melanoma (UM) is less than 0.5 % in the spectrum of human tumors, and less than 5 % among all types of melanoma, therefore, it is considered to be rare. At the same time, UM is recognized as the most common intraocular malignant neoplasm. Its share among all intraocular tumors is 60 %. Radical local treatments are considered effective, but the frequency of distant metastases is unacceptably high, and the life expectancy of patients with metastatic stage of the disease is short and on average is 4–5 months. Survival rates have remained stable for the past 40 years, reflecting the lack of current effective system strategies. The tumor metastasizes in a haematogenic way, so it is not surprising that angiogenesis is constantly in the focus of scientific developments. The importance of studying angiogenesis in UM is due to the ability to predict based on the quantitative indicators of vessels inside the tumor and to search for potential targets of antiangiogenic therapy in the future. The authors used two methods of studying angiogenesis in UM: morphological with quantitative vascular counting and immunohystochemical method (IHC) with markers of endothelial cells CD34 and CD31, VIII factor, VEGF molecules, bFGF, thrombospondin and others. IHC-staining of vessels in UM allowed to visualize vessels that were not visible due to intense pigmentation of tumors or compression of vessels by tumor cells. Comparison of data obtained by the two methods demonstrated the advantages of IHS analysis over classical morphological methods. It was found that UM, as a malignant solid tumor, differs high averages of vessels per unit area. The highest rates are recorded in epitheloid melanoma, which is associated with a higher rate of growth, and more frequent metastasis, compared to similar rates in revere cell melanoma. The number of vessels per unit area in the viewing area in UM decreases with age, which explained the development of metastases in more distant after enucleation time in elderly patients. Differences in vascular density in tumors of different localization were revealed and described: they were the maximum in pre-equatorial tumors, and minimal — in iris tumors.

True umbilical cord knots are not always knotty: a case report

<p class="abstract">A true umbilical cord knot (TUCK) is a rare event, complicating 0.3-1.3% of all pregnancies. Prenatal diagnosis is not usual, as it is mostly discovered at delivery, when the knot is identified. True cord knots are mostly asymptomatic, but can be associated with adverse perinatal outcomes such as birth asphyxia and foetal demise, owing to compression of the umbilical vessels within the knot. This compression, however, is largely dependent on how tightly the knot is formed. We report a 30-year-old booked gravida 2, para 1, with a living child, who had spontaneous vaginal delivery of a healthy male baby at term, with incidental finding of a single loose TUCK at delivery. The umbilical cord was 81 cm long. The baby weighed 3600 g at birth, with 1- and 5-minutes Apgar scores of 9 and 10 respectively, and no adverse perinatal occurrence.</p>

Transluminal compression increases mechanical stability, stiffness and endothelialization capacity of fibrin-based bioartificial blood vessels

Fibrin is used successfully as a biological matrix in various bioengineering approaches. Its unique combination of autologous availability, hemocompatibility and biological activity makes it an almost ideal matrix material for vascular tissue engineering. However, clinical application of fibrin-based bioartificial blood vessels is still limited due to insufficient mechanical stability and stiffness of fibrin matrices. Biomechanical properties of fibrin-based constructs can potentially be modified by adjusting matrix density. Thus, as an attempt to optimize strength and elasticity of fibrin matrices for vascular tissue engineering applications, we developed a simple and reproducible method for transluminal compression of small-diameter fibrin-based vessels: After initial polymerization of high-concentration fibrin matrices in a vascular mold, vessels were compressed using an intraluminal angioplasty balloon. Vessels compacted with different pressures were compared for ultimate strength, elastic and structural properties and cellularization capacity.Transluminal compression increased fibrin network density and facilitated rapid production of homogenous vessels with a length of 10 cm. Compared to non-compressed controls, compacted fibrin vessels showed superior maximal burst pressure (199.8 mmHg vs. 94.0 mmHg), physiological elastic properties similar to the elastic behavior of natural arteries and higher luminal endothelial cell coverage (98.6% vs. 34.6%). Thus, transluminal compaction represents a suitable technique to enhance biomechanical properties of fibrin-based bioartificial vessels while preserving the biological advantages of this promising biomaterial.

Adrenal Myelolipoma: 369 Cases From a High-Volume Center.

Background: Adrenal myelolipoma (AML) is a nonfunctional benign neoplasm from the adrenal cortex, composed of mature fat and hematopoietic tissue. Usually, patients have no symptoms. However, some patients with hypertension and blood pressure normalize after AML surgery, indicating some connections between AML and hypertension.Materials and Methods: This was a retrospective cohort study of 369 patients diagnosed with AML from September 2008 to December 2018 collected in the Urology Department of West China Hospital, Chengdu, Sichuan, China. We collected clinical records of patients before surgery. Postoperative follow-up was also carried out for those with hypertension and whether patients needed to take antihypertensive drugs and postoperative blood pressure were recorded. We aim to explore the characteristics of both patients with AML having hypertension and having remission of hypertension in 1 year after surgery.Results: There were 369 patients with AML included in the study, 156 men and 213 women, aged 49.86 ± 11.61 years old. Among them, 121 (32.8%) patients presented with hypertension. Body mass index was significantly higher in the hypertension group than that in the nonhypertension group, even after adjusting other variables (26.26 ± 3.43 vs. 24.28 ± 3.38 kg/m2, P < 0.001 for both univariate and multivariate analyses). Sixty patients were followed up for 1–9 years, with a median follow-up of 52 months. The duration of hypertension in the remission group was shorter than that in the non-remission group (P = 0.020), and the tumor lateralization was significantly different between the two groups (P = 0.005).Conclusions: Nearly one-third of patients with AML suffered from hypertension in our study, and there existed some potential links between AML and hypertension. To be more specific, AML-related hypertension was more likely to result from obesity and renal compression by perirenal fat than from endocrine disorders or blood vessels compression. Patients with AML and with more than 3 years of hypertension might have less possibility to recover.

Abstract LB016: Deep learning identifies pathobiological features within H&amp;E images associated with genomic alterations and progression on anti-PD(L)1 in HUDSON, an AstraZeneca-sponsored Phase II clinical trial

Abstract Introduction Machine learning (ML) models offer the potential to provide rich, quantitative characterizations of the tumor and tumor micro-environment (TME). Here we deployed a machine learning-based approach to the analysis of H&amp;E images from HUDSON (NCT03334617), an AstraZeneca Phase II Platform clinical trial, to identify and quantify cellular composition and tissue architecture features in the TME that are associated with genomic alterations and time to progression on anti-PD(L)1 therapies. Methods PathAI previously trained ML models on non-small cell lung carcinoma (NSCLC) samples from commercial and clinical datasets to identify cell types and tissue regions within the TME. With no additional training, the models were deployed on 169 digitized whole slide images (WSIs) of H&amp;E-stained biopsies from an international, multi-site AstraZeneca-sponsored Phase II clinical trial of novel anti-cancer agents in subjects with metastatic NSCLC. Biopsies were across multiple body sites, and taken both pre- and post-checkpoint progression. ML models generated human interpretable features (HIFs) that characterize the cell composition and tissue architecture from each biopsied sample. HIFs from baseline samples that met minimum image quality thresholds (n=89) were clustered to reduce redundancy and were tested for association with weeks to progression on anti-PD(L)1 therapy using Cox regression analysis. Results The PathAI ML models were successfully deployed on WSIs from the HUDSON clinical trial. Following correction for biopsy timing and location, a total of 59 HIFs were found to be significantly associated (p &amp;lt;0.05) with weeks to progression on anti-PD(L)1 therapy, including features related to plasma cell infiltration, proportion of cancer cells, presence of macrophages and fibroblasts, and blood vessel compression. Features characterizing both plasma cells and blood vessels were also found to be significantly associated with any class I HLA locus loss of heterozygosity. Conclusions PathAI models were able to identify TME-associated features from WSIs from a Phase II clinical trial which were associated with therapy failure and genomic alterations. These results suggest the power of deploying pre-trained ML-based systems in a clinical trial setting to identify pathobiological features associated with tumor characteristics and time to progression from only H&amp;E images. Citation Format: Laura Dillon, Marylens Hernandez, Ben Glass, Guillaume Chhor, Sara Hoffman, Varsha Chinnaobireddy, Sai Chowdary Gullapally, Kris Sachsenmeier, Andy Beck, Jason Hipp. Deep learning identifies pathobiological features within H&amp;E images associated with genomic alterations and progression on anti-PD(L)1 in HUDSON, an AstraZeneca-sponsored Phase II clinical trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB016.

Діагностика, лікування та реабілітація перекруту яєчка в дітей (огляд літератури)

Testiculat torsion (TT) is an emergency condition that is accompanied by partial or complete chorda spermatica vessels compression resulting in testicular infraction. TT main symptoms are sharp pain, scrotal hyperemia, generalized edema, nausea, vomiting and unconsciousness. However, these symptoms are characteristic of many other acute diseases of genital gland. In course of time the symptoms are less defined, which in its turn raises the issue of timely differential diagnostics. Purpose – to optimize and generalize about modern literature data on testicular torsion in children diagnostics, treatment and rehabilitation. Medical history taking, considering clinical data and checking the symptoms typical for PP during diagnostic process is crucial. It is important to use instrumental diagnostic methods, with echographic and scyntigraphic ones to be the main ones. After having confirmed PP diagnosis, treatment has to be started immediately. There are two methods of testicular detorsion, i.e. manual bloodless detorsion and invasive detorsion with further orchiopexy. Post-surgical phase is significant for preserving the patient’s fertility in the future. Post-TT rehabilitation includes medication, physiotherapeutic procedures, genital gland fixing from contralateral side, and, in case of testicle loss through non-timely treatment, testicle endoprosthesing. Testicular torsion is a complicated and understudied issue. Critical ischemia sets on in 12–16 hours from the onset of disease. As of today, the issue of diagnostics, treatment and rehabilitation of patients with acute testicular torsion has not been studied completely and requires further study. No conflict of interest was declared by the authors. Key words: testicular torsion, differential diagnosis, orchiopexy, endoprosthesis.

Compressed vessels bias red blood cell partitioning at bifurcations in a hematocrit-dependent manner: Implications in tumor blood flow

The tumor microenvironment is abnormal and associated with tumor tissue hypoxia, immunosuppression, and poor response to treatment. One important abnormality present in tumors is vessel compression. Vessel decompression has been shown to increase survival rates in animal models via enhanced and more homogeneous oxygenation. However, our knowledge of the biophysical mechanisms linking tumor decompression to improved tumor oxygenation is limited. In this study, we propose a computational model to investigate the impact of vessel compression on red blood cell (RBC) dynamics in tumor vascular networks. Our results demonstrate that vessel compression can alter RBC partitioning at bifurcations in a hematocrit-dependent and flow rate-independent manner. We identify RBC focusing due to cross-streamline migration as the mechanism responsible and characterize the spatiotemporal recovery dynamics controlling downstream partitioning. Based on this knowledge, we formulate a reduced-order model that will help future research to elucidate how these effects propagate at a whole vascular network level. These findings contribute to the mechanistic understanding of hemodilution in tumor vascular networks and oxygen homogenization following pharmacological solid tumor decompression.

Pediatric mediastinal mass algorithm: A quality improvement initiative to reduce time from presentation to biopsy.

Mediastinal masses in children may present with compression of the great vessels and airway. An interdisciplinary plan for rapid diagnosis, acute management, and treatment prevents devastating outcomes and optimizes care. Emergency pretreatment with steroids or radiation is more likely to be administered when care is variable, which may delay and complicate diagnosis and treatment. Strategies to standardize care and expedite diagnosis may improve acute patient safety and long-term outcomes. The aim of this quality improvement project was to decrease time from presentation to diagnostic biopsy for children with an anterior mediastinal mass by 50% over 3years within a tertiary healthcare system. This quality improvement project involved a single center with data collected and analyzed retrospectively and prospectively for 71 patients presenting with anterior mediastinal mass between February 2008 and January 2018. The Model for Improvement was utilized for project design and development of a driver diagram and smart aim. An algorithm was implemented to facilitate communication between teams and standardize initial care of patients with mediastinal masses. The algorithm underwent multiple Plan-Do-Study-Act (PDSA) cycles. Data were collected before and after algorithm implementation and between each PDSA cycle. The primary outcome measure included time from presentation to biopsy, which was monitored with a statistical process control chart. Several process measures were evaluated with Student's t-tests including administration of emergency pretreatment. Nineteen patients preintervention and 52 patients postintervention were included in the analysis. Time from presentation to biopsy significantly decreased from 48h at baseline to 24h postimplementation. Although not statistically significant, emergency pretreatment decreased from a baseline of 26.3% to 6.7% postimplementation. Implementation of a diagnostic and management algorithm coordinating care among multidisciplinary teams significantly reduced time to biopsy for children presenting with mediastinal mass and may result in decreased use of emergent pretreatment.

A rare case of syncronous solitary para-pharyngeal metastasis of clear cell carcinoma in a patient with small renal mass.

Unusual metastatic sites of renal cell carcinoma (RCC) are not infrequent. We report a rare case of solitary pharyngeal metastasis as first presentation of RCC. A 74 years-old man was referred to our hospital due to rapidly progressive dyspnoea and dysphagia. Physical examination showed a large right para-pharyngeal mass. Imaging findings showed a 5.5 cm mass, suspicious for malignancy, which extended to right para and retro-pharyngeal spaces with compression of the major right cervical vessels, C2-C3 vertebral bodies osteolysis, dural sac compression and dislocation. Futhermore, a small (2.6 × 2 cm) mass located at the upper pole of the right kidney was shown. Patient underwent partial trans-oral removal of the mass. Pathological examination and immunochemistry resulting strongly suggestive for metastatic RCC. Considering the metastatic stage of the tumour and the rapidly progressive clinical worsening with poor performance status, we offered the patient a palliative treatment with tyrosine kinase and cytoreductive radiotherapy on vertebral bodies. The patient developed a rapidly progressive multifocal metastatic disease and died 4 months after the presentation. We think that our case is noteworthy for some aspects. Firstly, pharyngeal localizations of RCC are very rare and this is the first case of solitary pharyngeal metastasis. Secondly, this metastatic lesion was really particular because it was synchronous and twice as big than the primary tumour. Thirdly, this case is consistent with previous evidence that synchronous compared with metachronous metastasis RCC is associated with adverse effect on outcome and response to targeted treatment.

In silico investigations of intratumoral heterogeneous interstitial fluid pressure

Recent preclinical studies have shown that interstitial fluid pressure (IFP) within tumors can be heterogeneous Andersen et al. (2019). In that study tumors of two xenograft models, respectively, HL-16 cervical carcinoma and Panc-1 pancreatic carcinoma, were investigated. Significant heterogeneity in IFP was reported and it was proposed that this was associated with division of tissue into compartments separated by thick connective tissue bands for the HL-16 tumors and with dense collagen-rich extracellular matrix for the Panc-1 tumors. The purpose of the current work is to explore these experimental observations by using in silico generated tumor models. We consider a mathematical multiphase model which accounts for tumor cells, fibroblasts and interstitial fluid. The model has been trained to comply with experimental in vitro results reported in Shieh et al. (2011) which has identified autologous chemotaxis, ECM remodeling, and cell-fibroblast interaction as drivers for invasive tumor cell behavior. The in silico model is informed with parameters that characterize the leaky intratumoral vascular network, the peritumoral lymphatics which collect the fluid, and the density of ECM as represented through the hydraulic conductivity of the interstitial space. Heterogeneous distribution of solid stress may result in heterogeneous compression of blood vessels and, thus, heterogeneous vascular density inside the tumor. To mimic this we expose the in silico tumor to an intratumoral vasculature whose net effect of density of blood vesssels and vessel wall conductivity is varied through a 2D Gaussian variogram constrained such that the resulting IFPs lie within the range as reported from the preclinical study. The in silico cervical carcinoma model illustrates that sparse ECM was associated with uniform intratumoral IFP in spite of heterogeneous microvascular network, whereas compartment structures resulted in more heterogeneous IFP. Similarly, the in silico pancreatic model shows that heterogeneity in the microvascular network combined with dense ECM structure prevents IFP to even out and gives rise to heterogeneous IFP. The computer model illustrates how a heterogeneous invasive front might form where groups of tumor cells detach from the primary tumor and form isolated islands, a behavior which is natural to associate with metastatic propensity. However, unlike experimental studies, the current version of the in silico model does not show an association between metastatic propensity and elevated IFP.

Output of a valveless Liebau pump with biologically relevant vessel properties and compression frequencies

Liebau pump is a tubular, non-peristaltic, pulsatile pump capable of creating unidirectional flow in the absence of valves. It requires asymmetrical positioning of the pincher relative to the attachment sites of its elastic segment to the rest of the circuit. Biological feasibility of such valveless pumps remains a hotly debated topic. To test the feasibility of the Liebau-based pumping in vessels with biologically relevant properties we quantified the output of Liebau pumps with their compliant segments made of a silicone rubber that mimicked the Young modulus of soft tissues. The lengths, the inner diameters, thicknesses of the tested compliant segments ranged from 1 to 5 cm, 3 to 8 mm and 0.3 to 1 mm, respectively. The compliant segment of the setup was compressed at 0.5–2.5 Hz frequencies using a 3.5-mm-wide rectangular piston. A nearest-neighbor tracking algorithm was used to track movements of 0.5-mm carbon particles within the system. The viscosity of the aqueous solution was varied by increased percentage of glycerin. Measurements yielded quantitative relationships between viscosity, frequency of compression and the net flowrate. The use of the Liebau principle of valveless pumping in conjunction with physiologically sized vessel and contraction frequencies yields flowrates comparable to peristaltic pumps of the same dimensions. We conclude that the data confirm physiological feasibility of Liebau-based pumping and warrant further testing of its mechanism using excised biological conduits or tissue engineered components. Such biomimetic pumps can serve as energy-efficient flow generators in microdevices or to study the function of embryonic heart during its normal development or in diseased states.

Crossing vessels with suspension versus transposition in laparoscopic pyeloplasty of patients with ureteropelvic junction obstruction: a retrospective study

PurposeTo compare the effects of two different methods of laparoscopic pyeloplasty for the treatment of crossing vessels.MethodsFrom January 2016 to August 2019, 33 patients with ureteropelvic junction obstruction (UPJO) underwent laparoscopic pyeloplasty at our center, including 21 men and 12 women, ranging from 14 to 66 years of age. There were 20 and 13 cases on the left and right sides, respectively. Patients underwent laparoscopic pyeloplasty (Anderson-Hynes operation). During the operation, either a Hem-o-lok clip suspension or transposition was used to treat the crossing vessels. The double-J stent was removed 8 weeks after the operation. The clinical data of patients were collected and follow-ups were regularly performed after the operation.ResultsAll the crossing vessels were successfully preserved, and none of them were severed during the operation. The average operation time was 210.6 ± 58.9 min in this group and the average time to manage the crossing vessel was 8.0 ± 3.5 min, 5.9 ± 1.4 min in the suspension group, and 11.7 ± 3.0 min in the transposition group. The dilation of the affected side was 4.8 ± 1.5 cm before operation and 1.2 ± 1.3 cm 3 months after operation. The difference was statistically significant (P < 0.05). Follow-up to February 2020 showed no significant changes in the kidney size in all patients and hydronephrosis was relieved.ConclusionFor UPJO patients with crossing vessel compression, the method of Hem-o-lok suspension or vascular transposition can be used to relieve crossing vascular compression and improve the success of pyeloplasty.

Retrosternal goitre: a diagnostic quandary

&lt;p class="abstract"&gt;Retrosternal goitre is usually referred to enlarged thyroid gland with more than 50% of its mass below the thoracic inlet. It has clinical importance because it may cause compression of the major vessels in the neck. In this article we are reporting a case of 51-year-old female who came to the otolaryngology clinic with slight dyspnoea on exertion for 3 years. She was an elderly female, obese, with a short broad neck with no obvious swelling in the neck. Surgical resection of the mass with either isolated neck incision or neck incision/sternotomy remains the treatment of choice.&lt;/p&gt;

Abstract PO-034: Changes in cancer associated fibroblast subsets following angiotensin II type I receptor blocker (ARB) treatment reduces transient hypoxia and radiation resistance

Abstract Poorly oxygenated (hypoxic) tumor cells are resistant to radiation and associated with poor patient outcomes. “Chronically” hypoxic cells develop from limited oxygen diffusion through tumor tissue. Changes in blood vessel perfusion cause fluctuations in oxygen delivery resulting in “transiently” hypoxic cells. Transiently hypoxic cells are often near vasculature and more metastatic than chronically hypoxic cells, identifying transient hypoxia as an important therapeutic target. Angiotensin II receptor (AT1R) type 1 blockers (ARBs) are anti-hypertensive agents with potential anti-fibrotic activity. ARB treatment reduces collagen 1 deposition (Col1) which is thought to occur by targeting AT1R-expressing cancer associated fibroblasts (CAFs) in solid tumors. AT1R signaling is activated through its ligand, angiotensin II (Ang II), which ARBs compete with to inhibit AT1R. It is unclear whether systemic sources of Ang II or localized tumor-derived Ang II contributes to CAF AT1R signaling and collagen deposition. Regardless, ARB-mediated inhibition of Col1 deposition was shown to reduced blood vessel compression and improved perfusion. We recently found that treatment with the ARB telmisartan substantially reduced Col1 deposition, stabilized vascular perfusion, and inhibited the development of transient hypoxia in a human tumor xenograft model. However, it only exhibited a modest reduction in CAF activation. Therefore, we hypothesized that only certain subsets of CAFs are responsible for the development of transient hypoxia in solid tumors, and that AT1R signaling between CAFs and cancer cells may be crucial for initiating the Col1 deposition leading to transient hypoxia development. Recent work by Dr. Mechta-Grigoriou’s group reliably identified four functionally distinct CAF subsets in patient breast and ovarian tumor samples using with a multi-color flow cytometry panel of CAF markers. To distinguish CAF subsets in a murine model, we used a similar flow cytometry panel and indeed, found distinguished subsets of CAFs in various human xenograft murine models. Additionally, we show that crosstalk between cancer cells and cancer associated fibroblasts (CAFs) exists in complementary secretion of Ang II and AT1R by cancer cells and cultured fibroblasts, respectively. This indicates that disruption of this localized Ang II may result in changes in CAF secretion and processing of Col1. We predict that this collaboration of CAFs and tumor cells is responsible for collagen deposition, which leads to blood vessel compression, hypoxia, and reduced radiation response. Citation Format: Che-Min Lee, Brennan J. Wadsworth, Kevin L. Bennewith. Changes in cancer associated fibroblast subsets following angiotensin II type I receptor blocker (ARB) treatment reduces transient hypoxia and radiation resistance [abstract]. In: Proceedings of the AACR Virtual Special Conference on Radiation Science and Medicine; 2021 Mar 2-3. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(8_Suppl):Abstract nr PO-034.

Treatment difficulties during COVID 19 pandemic in a patient with giant renal tumor. A small town general hospital perspective

Introduction: We present an unusual case of papillary renal cell carcinoma, which is a rare subtype of kidney malignancy. Objective: The present case report emphasizes a voluminous left renal tumoral mass causing bowel obstruction and necessity of emergency surgical intervention. Presentation of case: A 74 year old patient with a history of multiple severe cardiovascular conditions, presented in the emergency room accusing abdominal distension and pain, nausea, vomiting and lack of intestinal transit for about 72 hours. Based on the symptomatology, physical examination and imagistic explorations a clinical diagnosis of bowel obstruction was arisen, caused by a voluminous tumor with compression of the large vessels and invasion of the left colon. Given the severity of the cardiovascular comorbidities and the complexity of the case, the possibility of patient’s transfer to a university hospital was arisen, which was not practicable due to the COVID 19 pandemic. During surgical intervention en-bloc resection of the left kidney and tumoral mass was practiced. Histopathologic examination identified the tumoral mass as type I papillary carcinoma of the left kidney. The postoperative evolution was unfavorable, due to the severe cardiovascular comorbidities, on maximal vasoactive support the patient remained hemodynamically unstable, showed progressive myocardial infarction with the persistence of arrhythmias and severely reduced ejection fraction which led to his unfortunate death. Conclusion: Careful patient selection is needed to ensure a favorable risk-benefit ratio. Also a thorough multidisciplinary evaluation of patient and the possible therapeutic options is necessary, in order to create an optimal and individualized treatment plan

The Incidence of Venous Thromboembolism in Patients Undergoing Anterior Lumbar Interbody Fusion: A Proposed Thromboprophylactic Regime

To determine the safety and efficacy of the proposed venous thromboembolism (VTE) prophylaxis regime in patients undergoing anterior lumbar interbody fusion (ALIF) surgery. Deep vein thrombosis (DVT) and pulmonary embolism (PE) are recognized complications after spine surgery, with rates in the literature ranging from 0% to 14% with some form of prophylaxis. Pharmacological thromboprophylaxis can cause postoperative bleeding and hematomas, which can result in significant neural compromise or permanent injury, and wound complications. ALIF surgery involves the handling and compression of major abdominal vessels during surgery and this adds to the risk of both arterial thrombosis and VTE. A retrospective review of data, which were prospectively collected to evaluate the incidence of VTE in 200 consecutive patients undergoing ALIF following our VTE prophylaxis protocol. All patients had low molecular weight heparin, tinzaparin 4500 units subcutaneously on the evening before surgery, then daily for 3 to 5 days, then aspirin (acetylsalicylic acid) 150 mg daily plus lansoprazole 30 mg daily for 4 weeks after surgery. All patients had intermittent pneumatic compression of their calves and thighs intraoperatively and for 24 hours postoperatively then had early mobilization and thromboembolic deterrent stockings for 6 weeks. There was no incidence of any symptomatic VTE in the any of the 200 patients and no loss to follow-up. There was a 0% incidence of injury to the iliac vessels, symptomatic arterial occlusion, wound hematoma, major intraoperative bleeding, need for transfusion, symptomatic GI bleed, or retroperitoneal hematoma requiring intervention. The proposed VTE prophylactic regime is safe and efficacious and may decrease the incidence of symptomatic VTE in patients undergoing an ALIF procedure, and despite the use of chemical thromboprophylaxis, there is no evidence of bleeding complications as a result of using this regime. 4.

Implant-associated osteomyelitis: Development, characterisation, and application of a porcine model.

Implant-associated osteomyelitis: Development, characterisation, and application of a porcine model.