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A key platform underpinning the traditional understanding of the cardiovascular system, with respect to the behavior of large arterial vessels, is Otto Frank’s Windkessel Hypothesis [1]. This hypothesis posits simply that the smooth muscle walls of large arteries do not undergo rhythmic contractions in synchrony with the heartbeat but, rather, behave as passive elastic tubes undergoing distension from pulsatile pressure waves. The Windkessel Hypothesis is elegant, well described for over a century, ingrained in the understanding of cardiovascular medicine and physiology, and simply wrong. Several groups have now shown that the arterial smooth muscle wall undergoes rhythmic activation in synchrony with the heartbeat in a variety of tissues, including human brachial artery; canine coronary, femoral, and carotid arteries; rabbit aorta; feline pulmonary artery and rodent aorta [2-8]. The phasing of these events is such that the upstroke of the contraction slightly precedes the upstroke of the pulse wave, suggesting nomenclature for the events as pulse synchronized contractions, or PSCs [3,6-8]. PSCs have been found to be of neurogenic origin, sensitive to the neural blocker tetrodotoxin [3,8]. Although the specific neural pathways regulating PSCs have not been elucidated, the alpha-adrenergic system is at least partially involved, as evidenced by reduction or blockade of PSCs by the alpha-adrenergic blocker phentolamine [8]. Further, PSCs have not been observed following vessel excision in in vitro studies, as an intact nervous system is not present. The pacemaker for the PSC resides in the right atrium, as suggested by two lines of evidence. First, pacing of the right atrial region to faster than spontaneous frequencies leads to a one-to-one correspondence of PSC frequency with the stimulation rate [3]. Additionally, excision of the right, but not the left, atrial appendage results in elimination of PSCs [3]. As the pacemaker region for PSCs and the heartbeat both lie in the right atrium, this may potentially allow for coordination between the heartbeat and pulse wave with PSCs [3,5,8]. Extensive evaluations also have been performed showing the PSC was not an artifact produced either by cardiac contractility or from the vessel distension from the pulse wave [3,5,6].

Symptomatic vasospasm represents an uncommon complication of perimesencephalic nonaneurysmal subarachnoid hemorrhage (SAH) which is a benign form of SAH without any recognizable source of bleeding accounting for about 15% of non-traumatic SAH [1,2]. 

A growing number of synthetic plastics derived from fossil fuels are produced, and improper plastic waste management has caused a lot of pollution problems. There are many microplastics in the environment, and they disintegrate slowly in soil and water. The properties of microplastics (MPs) include long residence times, high stability, high fragmentation potential, and the ability to adsorb other contaminants. Invertebrates and planktonic organisms are easily able to accumulate microplastics in aquatic species. Therefore, microplastics (MPs) must be removed from the water and other media. This paper aims to review the occurrence, raw polymers and additives, and remediation methods for removing microplastics from the environment. Several methods are available for removing contaminants, including sorption, filtration and chemical treatments. Various removal methods are discussed along with their methods, efficiency and advantages.

Idiopathic Pulmonary Fibrosis (IPF) is a chronic and progressive disease without treatment that leads to death. Therefore, to control its progression to pulmonary hypertension is still a challenge. Moreover, there is no study that has investigated the Renin-Angiotensin System in patients with IPF. Objective: Verify the plasma concentrations of Angiotensin I, Angiotensin II (AngII), Angiotensin-(1-7) [Ang- (1-7)] and Alamandine in patients with IPF. Methods: Ten IPF patients, with or without PH, were included, and ten controls matched by sex and age. Quantitative plasma peptide concentrations (PPC) were expressed as mean and standard deviation or median and interquartile range. The Student Newman-Keuls t test was used for parametric data, Mann-Whitney for nonparametric data and, to compare proportions, the Fisher exact test was performed. The associations between clinical variables and the PPC were evaluated by Pearson or Spearman correlation coefficients. A p ≤ 0.05 was considered statistically significant. Results: The Alamandine plasma concentration was significantly (365%) lower in the IPF group and positively associated (r = 0.876) with pulmonary artery pressure (PAP). In addition, only in control group, the forced expiratory volume (FEV1%) was positively associated (p = 0.758) with Ang-(1-7). Conclusion: This study showed, for the first time, that there is a decrease in Alamandine participation in patients with IPF. The ACE-AngII-AT1 axis may be more active in this disease. In addition, our results suggest that Alamandine might be compensating the increase in PAP, as well as the Ang-(1-7) is improving the forced expiratory volume.

Objectives: Type-2 diabetes mellitus, caused by impaired secretion of insulin, is becoming one of the health hazardous threats to human lives across the world. Its prevalence is rising with time. In this study, 2750 phytochemicals, that are considered to have great ability to eliminate diseases caused by different viruses and bacteria, are obtained from different medicinal plants and discovery of inhibitors through in silico method was performed against Dipeptidyl peptidase-4 (DPP4). Method: The pharmacological assessment and pharmacokinetics of phytochemicals, molecular docking and density functional theory (DFT) analysis helped to explore the inhibitory action of phytochemicals against DPP4. Total forty-nine phytochemicals were screened initially to reduce the number of compounds to be analyzed further based on a threshold of binding affinity ≥ -5.5 kcal/mol and were considered for further computational studies to analyze their inhibitory effects for DPP4. For comparison and validation of the results of present study, various previously reported and experimentally validated compounds were docked with the DPP4. For these dockings, binding affinity was predicted and compared with those of phytochemicals to check if these phytochemicals are competent enough to be used as an inhibitor in the treatment of diabetes mellitus in the future. Results: Only four phytochemicals showed binding affinity greater than those of experimentally validated compounds. These included two phytochemicals from Silybum marianum, i.e. Diprenyleriodictyol and Taxifolin and while other two phytochemicals from Santolina insularis and Erythrina Varigatae i.e. Papraline and Osajin respectively. The reactivity levels for these four phytochemicals with the binding site residues of DPP4 were obtained by DFT based analysis, in which ELUMO, EHOMO and band energy gap were computed. Conclusion: Based on these results, it is concluded that these four phytochemicals, after passing through in vitro and in vivo validation, can be utilized as potential DPP4 inhibitors as they have strong properties as compared to those of various experimentally validated inhibitors.

Introduction: Diffuse axonal injury (DAI) is a major cause of disability in the pediatric patient. Herein we describe the MRI/DWI findings in a case with DAI. We also discuss the current role of CT and MRI with DWI in the evaluation of DAI. Aim of the study: To stress the role of diffusion-weighted imaging in diffuse axonal injury. Methods: A pediatric patient, who was hospitalized in the ICU, was submitted to MRI with DWI for the evaluation of brain lesions. The patient was scanned with T1-weighted images, T2-weighted images, FLAIR, T2*-weighted images and diffusion weighted images. Result: Brain lesions caused by DAI were more conspicuous on diffusion-weighted images compared to FLAIR images. T2*-weighted images were a helpful adjunct in showing micro-hemorrhages. Conclusion: T2*-weighted images and FLAIR images alone underestimate the true extent brain lesions in DAI compared to DWI.

Objective: To determine the prevalence of patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in labor and delivery units in one of the epicentres of the West Coast. Study Design: This was a retrospective chart review of patients admitted to labor and delivery from April 15, 2020-May 15, 2020 after implementation of a universal testing policy on Labor and Delivery. Results: The prevalence of patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the admitted labor and delivery population was 2.5%, of whom 87.5% were asymptomatic. Conclusion: We present additional data on the prevalence of asymptomatic SARS-CoV-2 in pregnant patients on the West Coast, which is much lower compared to other locales, possibly as a result of aggressive ‘shelter in place’ policy. Universal screening is insufficient to detect asymptomatic SARS-CoV-2 and thus rapid, universal testing should be prioritized for labor and delivery units for the protection of patients and staff, and to better allocate appropriate resources.  Key points: 1. 2.5% of 320 patients tested positive for SARS-CoV-2. 2. 87.5% of positive patients were asymptomatic. 3. Universal testing on labor and delivery is necessary. 4. ‘Shelter-in-place’ policies reduced SARS-CoV-2. 

The sequelae of deep and extensive burns to the abdomen can lead to serious complications during pregnancy. Studies and publications covering this subject are scarce and outdated. The complications described arise during the 3rd trimester of pregnancy, and surgical treatments to address these complications can initiate premature labor with a risk of fetal demise. We felt it would be of interest to prevent these complications through surgical treatments performed before the pregnancy. The need to reconstruct large regions of abdominal scar tissue prompted us to turn to the Integra® dermal equivalent for preventative surgical treatments.

Background: Adoption of the Lung Allocation Score (LAS) has led to increased listing of older patients and those with idiopathic pulmonary fibrosis (IPF) for lung transplantation (LTX). Older patients and those with IPF have higher prevalence of coronary artery disease (CAD), a relative contraindication for LTX. The impact of the LAS on CAD prevalence and cardiovascular morbidity in LTX recipients is unknown. Methods: Retrospective review of single institution database from January 2000 to December 2010. Patients with and without CAD were compared by age, gender, LAS, single vs double LTX, and transplant indication. Survival was calculated by Kaplan-Meier method, and statistical significance determined by log-rank method. Survival analysis was performed on all patients and by 3:1 propensity matching. Differences in CAD, gender, and indication were determined by Chi-squared test. Differences in LAS and age were calculated with a two-tailed t - test. Results: In the pre-LAS era, 6.2% (9/145) recipients had CAD vs. 9.2% (17/184) in the post-LAS era (p = 0.411). Among all patients, recipients with CAD had a worse long term survival as estimated by Kaplan-Meier method (p = 0.001), although there was no statistically significant difference after propensity matching ((p = 0.14). Although more recipients in the post-LAS era had a diagnosis of IPF [15/145 vs. 71/184 patients, (p < 0.001)], there was no difference in the prevalence of CAD in the IPF cohort compared to others. There were no differences in cardiovascular deaths among recipients with CAD, with IPF, or in the post-LAS era. Patients with a pre-transplant diagnosis of CAD had an descreased risk of new onset postoperative atrial fibrillation (AF) (p = 0.007; HR:0.133; CI:0.030-0.583). Conclusion: Adoption of the LAS was not associated with a significant change in proportion of recipients with CAD who underwent LTX at our institution, despite an increase in recipients with IPF. Recipients with CAD had a higher risk of developing new postoperative AF and worse survival than patients without CAD. Differences in survival, however, could not be attributed directly to CAD based on propensity matched analysis

Introduction: Arachnoid cyst (AC) is a congenital, benign, extra-axial lesion often found incidentally on intracranial imaging and makes up almost 1% of all intracranial masses. It arises from the splitting of arachnoid membranes with components similar to the cerebrospinal fluid. It’s reported that AC can be complicated by chronic subdural haematoma in athletes with repeated head injuries. Case report: we describe a case of a soccer player with an AC that underwent surgery for a chronic subdural haematoma with full recovery. Material and method: From a PubMed research, we found 14 relevant studies reporting a total of 15 patients who met the inclusion criteria: playing soccer, subdural hematoma and arachnoid cyst. Results: Patients underwent different surgical treatment. In the case of hygroma with no midline shift, a conservative treatment was performed. In all cases the reported follow up was a full recovery. Discussion: Soccer is not usually considered a contact sport related to a high risk of head trauma or shaking head. From our review we can postulate that a soccer player with AC has an augmented risk to have a subdural haemorrhage, more rarely intracerebral haemorrhage. Conclusion: ACs are common meningeal abnormalities. They may bleed after minor head trauma, although it is rare. Asymptomatic patients with known AC should be monitored by a neurosurgeon and decision to engage this patient in soccer sport participation is still controversial.