Infection is a major complication of implantable medical devices, which provide a scaffold for biofilm formation, thereby reducing susceptibility to antibiotics and complicating treatment. ...Hematogenous implant-related infections following bacteremia are particularly problematic because they can occur at any time in a previously stable implant. Herein, we developed a model of hematogenous infection in which an orthopedic titanium implant was surgically placed in the legs of mice followed 3 wk later by an i.v. exposure to Staphylococcus aureus. This procedure resulted in a marked propensity for a hematogenous implant-related infection comprised of septic arthritis, osteomyelitis, and biofilm formation on the implants in the surgical legs compared with sham-operated surgical legs without implant placement and with contralateral nonoperated normal legs. Neutralizing human monoclonal antibodies against α-toxin (AT) and clumping factor A (ClfA), especially in combination, inhibited biofilm formation in vitro and the hematogenous implant-related infection in vivo. Our findings suggest that AT and ClfA are pathogenic factors that could be therapeutically targeted against S. aureus hematogenous implant-related infections.
Objectives
Out‐of‐hospital cardiac arrest (OHCA) afflicts >350,000 people annually in the United States. While postarrest coronary angiography (CAG) with percutaneous coronary intervention (PCI) has ...been associated with improved survival in observational cohorts, substantial uncertainty exists regarding patient selection for postarrest CAG. We tested the hypothesis that symptoms consistent with acute coronary syndrome (ACS), including chest discomfort, prior to OHCAs are associated with significant coronary lesions identified on postarrest CAG.
Methods
We conducted a multicenter retrospective cohort study among eight regional hospitals. Adult patients who experienced atraumatic OHCA with successful initial resuscitation and subsequent CAG between January 2015 and December 2019 were included. We collected data on prehospital documentation of potential ACS symptoms prior to OHCA as well as clinical factors readily available during postarrest care. The primary outcome in multivariable regression modeling was the presence of significant coronary lesions (defined as >50% stenosis of left main or >75% stenosis of other coronary arteries).
Results
Four‐hundred patients were included. Median (interquartile range) age was 59 (51–69) years; 31% were female. At least one significant stenosis was found in 62%, of whom 71% received PCI. Clinical factors independently associated with a significant lesion included a history of myocardial infarction (adjusted odds ratio aOR = 6.5, 95% confidence interval {CI} = 1.3 to 32.4, p = 0.02), prearrest chest discomfort (aOR = 4.8 95% CI = 2.1 to 11.8, p ≤ 0.001), ST‐segment elevations (aOR = 3.2 95% CI = 1.7 to 6.3, p < 0.001), and an initial shockable rhythm (aOR = 1.9 95% CI = 1.0 to 3.4, p = 0.05).
Conclusions
Among survivors of OHCA receiving CAG, history of prearrest chest discomfort was significantly and independently associated with significant coronary artery lesions on postarrest CAG. This suggests that we may be able to use prearrest symptoms to better risk stratify patients following OHCA to decide who will benefit from invasive angiography.
There is broad consensus that resuscitated out-of-hospital cardiac arrest (OHCA) patients with ST-segment elevation myocardial infarction (STEMI) should receive immediate coronary angiography (CAG); ...however, factors that guide patient selection and optimal timing of CAG for post-arrest patients without evidence of STEMI remain incompletely described.
We sought to describe the timing of post-arrest CAG in actual practice, patient characteristics associated with decision to perform immediate vs. delayed CAG, and patient outcomes after CAG.
We conducted a retrospective cohort study at seven U.S. academic hospitals. Resuscitated adult patients with OHCA were included if they presented between January 1, 2015 and December 31, 2019 and received CAG during hospitalization. Emergency medical services run sheets and hospital records were analyzed. Patients without evidence of STEMI were grouped and compared based on time from arrival to CAG performance into “early” (≤ 6 h) and “delayed” (> 6 h).
Two hundred twenty-one patients were included. Median time to CAG was 18.6 h (interquartile range IQR 1.5–94.6 h). Early catheterization was performed on 94 patients (42.5%) and delayed catheterization was performed on 127 patients (57.5%). Patients in the early group were older (61 years IQR 55–70 years vs. 57 years IQR 47–65 years) and more likely to be male (79.8% vs. 59.8%). Those in the early group were more likely to have clinically significant lesions (58.5% vs. 39.4%) and receive revascularization (41.5% vs. 19.7%). Patients were more likely to die in the early group (47.9% vs. 33.1%). Among survivors, there was no significant difference in neurologic recovery at discharge.
OHCA patients without evidence of STEMI who received early CAG were older and more likely to be male. This group was more likely to have intervenable lesions and receive revascularization.
Background
As transplant centers start leveraging Twitter for information dissemination and public engagement, it is important to understand current living solid organ donation‐related Twitter use.
...Methods
We identified public Twitter profiles available in 01/2017 that referenced living organ donation and analyzed the use of donation‐related Twitter handles, names, or profile information. Tweets were manually ed and qualitatively analyzed for common themes. Social media influence of those tweeting about living donation was evaluated using Klout score.
Results
We identified 93 donors, 61 professionals, 12 hospitals, and 19 organizations that met eligibility criteria. Social media influence was similar across these groups (P = 0.4). Donors (16%) and organizations (23%) were more likely than professionals (7%) or hospitals (0%) to include transplant‐related educational information in their profiles (P = 0.007). Living donation‐related tweets were most commonly donation stories (33%), news reports (20%), reports about new transplant research (15%), and sharing transplant candidates’ searches for donors (14%).
Conclusions
This exploratory study of living donors and transplant professionals, hospitals, and organizations on Twitter provides insight into how the social media platform may be used to communicate about and disseminate information about living donation.
Climbing and trekking at altitude are common recreational and military activities. Physiological effects of altitude are hypoxia and hyperventilation. The hyperventilatory response to altitude may ...cause respiratory muscle fatigue and reduce sustained submaximal exercise. Voluntary isocapnic hyperpnea respiratory muscle training (VIHT) improves exercise endurance at sea level and at depth. The purpose of this study was to test the hypothesis that VIHT would improve exercise time at altitude 3600 m (11,811 ft) compared to control and placebo groups.
Subjects pedaled an ergometer until exhaustion at simulated altitude in a hypobaric chamber while noninvasive arterial saturation (Sao2), ventilation (VE), and oxygen consumption (Vo2) were measured.
As expected, Sao2 decreased to 88 ± 4% saturation at rest and to 81 ± 2% during exercise, and was not affected by VIHT. VIHT resulted in a 40% increase in maximal training VE compared to pre-VIHT. Exercise endurance significantly increased 44% after VIHT (P = <0.001). Vo2 (30 ± 3 ml · kg(-1) · min(-1)) and heart rate (177 ± 10 bpm) did not change during exercise and were not affected by VIHT (P = 0.531). Pre-VIHT VE increased 21-27% during the initial 12 min of exercise, after which it decreased 17% at 17.7 ± 6.0 min. VE at altitude post-VIHT increased more (49%) for longer (21 min) and decreased less (11% at 25.4 ± 6.7 min).
VIHT improved exercise time at altitude and sustained VE. This suggests that VIHT reduced respiratory muscle fatigue and would be useful to trekkers and military personnel working at altitude. Helfer S, Quackenbush J, Fletcher M, Pendergast DR. Respiratory muscle training and exercise endurance at altitutde. Aerosp Med Hum Perform. 2016; 87(8):704-711.
Hiking and trekking often occur at altitudes up to 12,000 ft altitude. The hypoxia-induced hyperventilation at altitude paradoxically reduces arterial CO2 (Paco2). A reduction in Paco2 results in ...vasoconstriction of the blood vessels of the brain and thus in local hypoxia. The local hypoxia likely affects cognitive function, which may result in reduced performance and altitude accidents. Recent publications have demonstrated that voluntary isocapnic hyperventilatory training of the respiratory muscles (VIHT) can markedly enhance exercise endurance as it is associated with reduced ventilation and its energy cost. VIHT may be useful in blunting the altitude-induced hyperventilation leading to higher Paco2 and improved cognitive function.
This study examined the effects of VIHT, compared to control (C) and placebo (PVIHT) groups, on selected measures of executive functioning, including working memory and processing speed (i.e., Stroop Test, Symbol Digit Modalities Test, and Digit Span Forward) at simulated altitude up to 12,000 ft. Associated physiological parameters were also measured.
The Digit Span Forward Test did not show improvements after VIHT in any group. The VIHT group, but not C or PVIHT groups, improved significantly (17-30%) on the Stroop Test. Similarly the VIHT group, but not the C and PVIHT groups, improved correct responses (26%) and number of attempts (24%) on the Symbol Digit Modalities Test. In addition, reaction time was also improved (16%).
VIHT improved processing speed and working memory during exercise at altitude.
4-methyl-N-ethcathinone (4-MEC), the N-ethyl homologue of mephedrone, is a novel psychoactive substance of the beta-keto amphetamine (cathinone) group. The aim of the present work was to study the ...phase I and phase II metabolism of 4-MEC in human urine as well as in pooled human liver microsome (pHLM) incubations. The urine samples were worked up with and without enzymatic cleavage, the pHLM incubations by simple deproteinization. The metabolites were separated and identified by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-high resolution-tandem mass spectrometry (LC-HR-MS/MS). Based on the metabolites identified in urine and/or pHLM, the following metabolic pathways could be proposed: reduction of the keto group, N-deethylation, hydroxylation of the 4-methyl group followed by further oxidation to the corresponding 4-carboxy metabolite, and combinations of these steps. Glucuronidation could only be observed for the hydroxy metabolite. These pathways were similar to those described for the N-methyl homologue mephedrone and other related drugs. In pHLM, all phase I metabolites with the exception of the N-deethyl-dihydro isomers and the 4-carboxy-dihydro metabolite could be confirmed. Glucuronides could not be formed under the applied conditions. Although the taken dose was not clear, an intake of 4-MEC should be detectable in urine by the GC-MS and LC-MS(n) standard urine screening approaches at least after overdose.
Little is known about the prognosis of patients with massive pulmonary embolism (PE) and its risk of recurrent venous thromboembolism (VTE) compared with non-massive PE, which may inform clinical ...decisions. Our aim was to compare the risk of recurrent VTE, bleeding, and mortality after massive and non-massive PE during anticoagulation and after its discontinuation.
We included all participants in the RIETE registry who suffered a symptomatic, objectively confirmed segmental or more central PE. Massive PE was defined by a systolic hypotension at clinical presentation (<90 mm Hg). We compared the risks of recurrent VTE, major bleeding, and mortality using time-to-event multivariable competing risk modeling. There were 3.5% of massive PE among 38 996 patients with PE. During the anticoagulation period, massive PE was associated with a greater risk of major bleeding (subhazard ratio sHR 1.72, 95% confidence interval CI 1.28-2.32), but not of recurrent VTE (sHR 1.15, 95% CI 0.75-1.74) than non-massive PE. An increased risk of mortality was only observed in the first month after PE. After discontinuation of anticoagulation, among 11 579 patients, massive PE and non-massive PE had similar risks of mortality, bleeding, and recurrent VTE (sHR 0.85, 95% CI 0.51-1.40), but with different case fatality of recurrent PE (11.1% versus 2.4%, P = .03) and possibly different risk of recurrent fatal PE (sHR 3.65, 95% CI 0.82-16.24).
In this large prospective registry, the baseline hemodynamic status of the incident PE did not influence the risk of recurrent VTE, during and after the anticoagulation periods, but was possibly associated with recurrent PE of greater severity.