Institution of same-day total joint replacement at an urban safety net hospital during the COVID-19 pandemic.

Background: Increasingly, total hip and total knee replacements are being performed at outpatient ambulatory surgery centers. The purpose of this study was to investigate the feasibility and safety of instituting a same-day surgery program for hip and knee replacement at an urban, safety net hospital. Methods: Retrospective review of a prospectively collected registry for all patients scheduled for same-day total joint replacement at a safety net hospital was performed. Medical records were reviewed for patient demographics, same-day hospital admissions, and 30-day emergency room/hospital admissions. Results: 131 same-day total joint replacements were identified, including 76 knees and 55 hips. Median ASA was 3, and median Charlson comorbidity score was 2. Rate of same-day surgery for total joint replacements increased from 4.5% in September 2020 to 100% in September 2021. On major patient outcomes, 3.8% of patients (n = 5) required conversion to inpatient admission. Rate of 30-Day Emergency Department (ED) visits was 13.0% (n = 17). Most common complaints included postoperative pain (n = 10), incision drainage/edema/hematoma (n = 9), and cellulitis (n = 2). 30-Day Hospital Readmissions occurred in 1.5% of patients (n = 2). Conclusion: Same-day hip and knee replacement can be performed safely at a safety net hospital. Unlike dedicated high-volume orthopedic hospitals or outpatient surgery centers, urban safety net hospitals face a different set of challenges and must care for a wide variety of patients who do not plan for their illness and/or may not be able to pay for their care. Outpatient total joint replacement may extend total joint replacement to patients who might not have access otherwise.

Paving the way towards green catalytic materials for green fuels: impact of chemical species on Mo-based catalysts for hydrodeoxygenation.

A series of Mo-based catalysts were synthesized by tuning the sulfidation temperature to produce mixtures of MoO3 and MoS2 as active phases for the hydrodeoxygenation (HDO) of palmitic acid. Differences in the oxidation states of Mo, and the chemical species present in the catalytic materials were determined by spectroscopic techniques. Palmitic acid was used as a fatty-acid model compound to test the performance of these catalysts. The catalytic performance was related to different chemical species formed within the materials. Sulfidation of these otherwise inactive catalysts significantly increased their performance. The catalytic activity remains optimal between the sulfidation temperatures of 100 °C and 200 °C, whereas the most active catalyst was obtained at 200 °C. The catalytic performance decreased significantly at 400 °C due to a higher proportion of sulfides formed in the materials. Furthermore, the relative proportion of MoO3 to MoS2 is essential to form highly active materials to produce O-free hydrocarbons from biomass feedstock. The transition from MoS2 to MoO3 reveals the importance of Mo-S and Mo-O catalytically active species needed for the HDO process and hence for biomass transformation. We conclude that transitioning from MoS2 to MoO3 catalysts is a step in the right direction to produce green fuels.

Adsorption of Biomass-Derived Products on MoO3: Hydrogen Bonding Interactions under the Spotlight.

We performed a computational study on the interaction of O-containing compounds coming from biomass with a catalytic surface of MoO3. The addition of H atoms on the metal oxide surface mimics different scenarios of its exposure to the ambient or protons coming from biomass. Representative compounds from fatty acids (from triacylglycerides) and aromatics (from lignin) were adsorbed on the metal oxide surfaces. We covered the complete H surface coverage, and the adsorbed molecules showed structural changes due to the interactions in turn. The driven force interactions in this process is hydrogen bonding, which reveals the complexity in biomass processing. H-bonds were fully characterized by the electron density and its Laplacian where bond critical points are present. These topological properties allow us to understand the correlation between the adsorption energies and the strength on each adsorption site. We also computed the relative Gibbs energies and harmonic oscillator model of aromaticity index of the adsorbed molecules to get more insights into their stability.

Survival After Long-Term Residence in an Intensive Care Unit.

A higher mortality trend correlated with increased age and length of stay for medical and surgical patients in the intensive care unit.

The evolving role of preoperative testing in vascular surgery patients: can a little knowledge be dangerous?

It has been traditionally recommended that candidates for vascular surgery receive noninvasive stress perfusion testing risk stratification to help decide which patients may benefit from coronary artery revascularization. Recent clinical trials have contested the efficacy of revascularization in this population as well as the information yield of noninvasive testing. This article reviews a number of these studies that are likely to change our beliefs regarding testing and subsequent interventions as well as evolving role of medical therapy in patients undergoing vascular surgery.

Sickle cell disease and stroke.

Twenty-four percent of sickle cell disease (SCD) patients have a stroke by the age of 45 years. Blood transfusions decrease stroke risk in patients deemed high risk by transcranial Doppler. However, transcranial Doppler has poor specificity, and transfusions are limited by alloimmunization and iron overload. Transfusion withdrawal may be associated with an increased rebound stroke risk. Extended blood typing decreases alloimmunization in SCD but is not universally adopted. Transfusions for thalassemia begun in early childhood are associated with lower rates of alloimmunization than are seen in SCD, suggesting immune tolerance. Optimal oxygen transport efficiency occurs at a relatively low hematocrit for SCD patients because of hyperviscosity. Consequently, exchange rather than simple transfusions are more effective in improving oxygen transport efficiency, but the former are technically more demanding and require more blood units. Although viscosity is of importance in the noncerebral manifestations of SCD, inflammation may play a larger role than viscosity in the development of large-vessel stroke. The future of SCD stroke management lies in the avoidance of transfusion. Hydroxyurea and anti-inflammatory measures may reduce the need for transfusion. Recent genome-wide association studies may provide methods for modulating fetal hemoglobin production enough to attenuate stroke risk and other complications of SCD.

MRI-based selection for intra-arterial stroke therapy: value of pretreatment diffusion-weighted imaging lesion volume in selecting patients with acute stroke who will benefit from early recanalization.

BACKGROUND AND PURPOSE: Recent studies demonstrate that an acute diffusion-weighted imaging lesion volume >70 cm(3) predicts poor outcome in patients with stroke. We sought to determine if this threshold could identify patients treated with intra-arterial therapy who would do poorly despite reperfusion. In patients with initial infarcts <70 cm(3), we sought to determine what effect recanalization and time to recanalization had on infarct growth and functional outcome. METHODS: We retrospectively studied 34 consecutive patients with anterior circulation stroke who underwent pretreatment diffusion-weighted imaging and perfusion-weighted imaging and subsequent intra-arterial therapy. Recanalization success and time to recanalization were recorded. Initial diffusion-weighted imaging and mean transit time lesion and final infarct volumes were determined. Patients were stratified based on initial infarct volume, recanalization status, and time to recanalization. Statistical tests were performed to assess differences in clinical and imaging outcomes. Good clinical outcome was defined as a 3-month modified Rankin Scale score 70 cm(3), all had poor outcomes despite a 50% recanalization rate with mean infarct growth of 114 cm(3). These patients also had the largest mean transit time volumes (P<0.04). Patients with initial infarct volumes <70 cm(3) who recanalized early had the best clinical outcomes (P<0.008) with a 64% rate of modified Rankin Scale score

In vivo fate and therapeutic efficacy of PF-4/CTF microspheres in an orthotopic human glioblastoma model.

The correlation between glioma grade and angiogenesis suggests that antiangiogenic therapies are potentially therapeutically effective for these tumors. However, to achieve tumor suppression, antiangiogenic therapies need to be administered daily using high systemic quantities. We designed a biodegradable polymeric device that overcomes those barriers by providing sustained local delivery of a C-terminal fragment of platelet factor 4 (PF-4/CTF), an antiangiogenic agent. Fluorescent-labeled microspheres composed of poly lactic-coglycolic acid (PLGA) were loaded with rhodamine-labeled PF-4/CTF and formulated to release their contents over time. Fluorescent labeling enabled the correlation between the in vitro to the in vivo kinetic and release studies. PF-4/CTF microspheres were injected into established intracranial human glioma tumors in nude mice. Noninvasive magnetic resonance imaging (MRI) was used to assess the therapeutic response. Tumor size, microvessel density, proliferation, and apoptosis rate were measured by histological analysis. Intracranially, the microspheres were located throughout the tumor bed and continuously released PF-4/CTF during the entire experimental period. MRI and histological studies showed that a single injection of microspheres containing PF-4/CTF caused a 65.2% and 72% reduction in tumor volume, respectively, with a significant decrease in angiogenesis and an increase in apoptosis. Our data demonstrate that polymeric microspheres are an effective therapeutic approach for delivering antiangiogenic agents that result in the inhibition of glioma tumor growth.

Alpha2A-adrenoceptor stimulation improves prefrontal cortical regulation of behavior through inhibition of cAMP signaling in aging animals.

The working-memory functions of the prefrontal cortex (PFC) are improved by stimulation of postsynaptic, alpha2A-adrenoceptors, especially in aged animals with PFC cognitive deficits. Thus, the alpha2A-adrenoceptor agonist, guanfacine, greatly improves working-memory performance in monkeys and rats following systemic administration or intra-PFC infusion. Alpha2A-adrenoceptors are generally coupled to Gi, which can inhibit adenylyl cyclases and reduce the production of cAMP. However, no study has directly examined whether the working-memory enhancement observed with guanfacine or other alpha2A-adrenoceptor agonists results from cAMP inhibition. The current study confirmed this hypothesis in both rats and monkeys, showing that treatments that increase cAMP-mediated signaling block guanfacine's beneficial effects. In aged rats, guanfacine was infused directly into the prelimbic PFC and was challenged with co-infusions of the cAMP analog, Sp-cAMPS. In aging monkeys, systemically administered guanfacine was challenged with the phosphodiesterase 4 inhibitor, rolipram, using intramuscular doses known to have no effect on their own. In both studies, agents that mimicked the actions of cAMP (rats) or increased endogenous cAMP (monkeys) completely blocked the enhancing effects of guanfacine on working-memory performance. These results are consistent with alpha2A-adrenoceptor stimulation enhancing PFC working-memory function via inhibition of cAMP-mediated signaling.