Search

The persistence patterns of high-priority bacterial strains from the Canadian Domestic Substance List (DSL) are examined and specific DNA markers for DSL bacterial strains are developed by using the amplified fragment length polymorphism (AFLP) method. The studies have shown that the DSL strains can be quantitatively tracked in soil with high sensitivity and specificity at the functional strain level, which has provided the basic evidence for risk assessment of the priority DSL strains.

Myotonic dystrophy type 1 (DM1) is an autosomal dominant disorder with a broad spectrum of systemic manifestations, including cardiac abnormalities. Takotsubo cardiomyopathy, a form of stress-induced transient heart failure, is not typically associated with DM1, and its occurrence in this patient population remains poorly characterized. This case series aims to describe two instances of Takotsubo cardiomyopathy in patients with DM1, highlighting potential links between the neuromuscular and cardiac pathophysiology of DM1 and stress-induced cardiomyopathy. We reviewed the clinical presentation, diagnostic findings, and outcomes of two patients with genetically confirmed DM1 who developed Takotsubo cardiomyopathy. Data were collected from medical records, including electrocardiograms, echocardiograms, cardiac biomarkers, and imaging studies. A review of the literature was conducted to contextualize the findings. The two patients presented in this case series exhibited distinct triggers and clinical presentations. The first patient, a 39-year-old woman, developed chest pain following intractable nausea and vomiting, while the second patient, a 62-year-old woman, experienced palpitations after the emotional stress of her 28-year-old daughter's passing. Despite these differing triggers, both cases showed imaging findings characteristic of Takotsubo cardiomyopathy, including left ventricular apical ballooning and reduced ejection fraction. Both patients were diagnosed with DM1, and their cardiac functions fully recovered within weeks. This case series highlights the importance of recognizing Takotsubo cardiomyopathy as a potential cardiac complication in patients with DM1. Shared neuromuscular and cardiac pathophysiology between DM1 and Takotsubo cardiomyopathy warrants further investigation to elucidate underlying mechanisms and guide management strategies., (© 2025 Wiley Periodicals LLC.)

We present a case of a young woman having recurrent admissions secondary to cyclical vomiting syndrome complicated with stress-induced cardiomyopathy/takotsubo cardiomyopathy (TC). She not only had left ventricular dysfunction but also suffered from anxiety and post-traumatic stress disorder for which professional help was sought. TC is defined as reversible, transient ventricular dysfunction in the absence of coronary artery disease. Due to the similarity of TC to acute coronary syndrome, TC is often left as a diagnosis of exclusion as it relies heavily on diagnosis by history, physical examination, and ultrasound imaging. Extreme emotional or physical stress can act as a trigger and timely identification and management of triggers causing TC are important to improve the outcome. In addition to physiological impact, TC also puts a toll on psychological health. Although the mechanism is not completely understood, reportedly plasma levels of epinephrine and norepinephrine were significantly elevated in patients with TC which might contribute to depression, anxiety, and psychological distress. Along with proper medical care, psychological care is equally important for patients with TC., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Akram et al.)

Introduction: Lipoprotein(a) [Lp(a)] is a genetically determined independent risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve disease. Despite recommendations from professional societies in the cardiovascular field, the awareness of elevated Lp(a) as a risk factor and screening for Lp(a) are suspected to be low., Methods: We conducted a retrospective, observational case control study of patient charts from January 1, 2017 to June 19, 2022. The primary aims were 1) to describe the proportion of patients at the healthcare network's primary care and cardiology clinics that met Lp(a) screening criteria and were tested; and 2) to describe the proportion of patients throughout the entire healthcare network that had Lp(a) measured., Results: Of the 2,412,020 patient charts in the health network, only 5,942 (0.25 %) had Lp(a) measured. Of the 84,581 patients in primary care or cardiology clinics who met screening criteria, only 1,311 (1.55 %) had Lp(a) measured. Patients with Lp(a) measured were more likely to be younger, non-Hispanic/Latinx, had a lipid panel measured, a cardiac computed tomography (CT) imaging study, and higher low-density lipoprotein-cholesterol. Patients with ASCVD, heart failure, ischemic heart disease, aortic stenosis, peripheral vascular disease, or a stroke did not feature highly among patients who received Lp(a) testing. Having an abnormal or risk-enhancing Lp(a) level was associated with being female and/or being Black/African American., Conclusions: Despite increased awareness of Lp(a) and its contribution to cardiovascular disease there exists a paucity of testing. Increased Lp(a) testing can identify patients who have an increased cardiovascular risk underestimated by other metrics., (Copyright © 2023. Published by Elsevier Inc.)

We report a tunable all-fiber laser emitting a maximum output power of 2.55 W around 3240 nm. The fiber laser cavity based on a fluoride fiber doped with dysprosium ions yields an efficiency of 42% according to the in-band launched pump power at 2825 nm. Due to a custom piezoelectric fiber Bragg grating (FBG) package, mechanical strains applied to the narrowband FBG used as the input cavity coupler allowed for fast tuning of the emission wavelength over a spectral range of 1.5 nm. This laser was deployed in the field in northern Québec (Canada) to assess its performances for remote sensing of methane in the presence of a significant amount of water vapor, i.e., over a hydroelectric reservoir. The preliminary results acquired during this field campaign confirm the great potential of the proposed approach for the development of a real-time active imaging system of greenhouse gases.

Mid-infrared fiber sources, emitting between 2.5 µm and 5.0 µm, are interesting for their great potential in several application fields such as material processing, biomedicine, remote sensing and infrared countermeasures due to their high-power, their diffraction-limited beam quality as well as their robust monolithic architecture. In this review, we will focus on the recent progress in continuous wave and pulsed mid-infrared fiber lasers and the components that bring these laser sources closer to a field deployment as well as in industrial systems. Accordingly, we will briefly illustrate the potential of such mid-infrared fiber lasers through a few selected applications.

A 17-year-old boy with a recent diagnosis of COVID-19 infection was admitted with acute chest pain due to type A aortic dissection and was subsequently diagnosed with the Marfan syndrome. Literature shows an increased rate of aortic dissection during flu season. The hypothesis is that a cytokine storm triggers the dissection., (Copyright © 2021 Baylor University Medical Center.)

We report a 2800 nm E r 3+ -doped fluoride fiber amplifier that delivers 1 mJ pulses with an average power of 5 W and pulse duration of 1 ns at 5 kHz repetition rate. To the best of our knowledge, this is the highest pulse energy achieved from a fluoride-fiber-based system operating near 3 µm, and the W-level average power and short pulse lengths make the system a promising tool for biomaterials processing.

We report a novel technique for side-pumping fluoride-based double-clad fibers, allowing a record coupling efficiency of 93% and a maximum power handling near 100 W at 981 nm. Our simple technique is based on wrapping a silica taper around a fluoride fiber and, therefore, does not require any complex fusion between these two dissimilar fibers. Under passive cooling, pump combiners made of undoped and erbium-doped fluoride fibers were successfully operated during several hours at respective incident powers of 91 and 44 W. Heat management issues and active cooling strategies are also discussed. This innovative combiner is a keystone towards the development of compact and robust high-power mid-infrared fiber lasers and amplifiers.

In this Letter, we report, to the best of our knowledge, the first demonstration of an in-band pumped gain-switched D y 3+ -doped fiber laser operating at 3.24 µm. The monolithic cavity bounded by two fiber Bragg gratings was pumped by a gain-switched E r 3+ -doped fiber system. It produced stable nanosecond pulses in a single-pulse regime on its entire operating range from 20 kHz to 120 kHz. A record average power of 1.43 W was achieved for a repetition rate of 120 kHz, and a record pulse energy of 19.2 µJ was achieved at 60 kHz. These results represent a significant improvement in D y 3+ -doped pulsed fiber laser performances and open the way to applications in the fields of remote sensing and material processing.

Within Canada, screening-level assessments for chemical substances are required to determine whether the substances pose a risk to human health and/or the environment, and as appropriate, risk management strategies. In response to the volume of metal and metal-containing substances, process efficiencies were introduced using a metal-moiety approach, whereby substances that contain a common metal moiety are assessed simultaneously as a group, with the moiety of concern consisting of the metal ion. However, for certain subgroups, such as organometals or organic metal salts, the organic moiety or parent substance may be of concern, rather than simply the metal ion. To further investigate the need for such additional consideration, certain substances were evaluated: zinc (Zn)-containing inorganic (Zn chloride [ZnCl2] and Zn oxide) and organic (organometal: Zn diethyldithiocarbamate [Zn(DDC) 2 ] and organic metal salts (Zn stearate [ZnSt] and 4-chloro-2-nitrobenzenediazonium tetrachlorozincate [BCNZ]). The toxicity of the substances were assessed using plant (Trifolium pratense and Elymus lanceolatus) and soil invertebrate (Folsomia candida and Eisenia andrei) tests in a sandy soil. Effect measures were determined based on total metal and total parent analyses (for organic substances). In general, the inorganic Zn substances were less toxic than the organometals and organic metal salts, with 50% effective concentrations ranging from 11 to >5194 mg Zn kg -1 dry soil. The data demonstrate the necessity for alternate approaches in the assessment of organo-metal complexes, with the organic moieties or parent substances warranting consideration rather than the metal ion alone. In this instance, the organometals and organic metal salts were significantly more toxic than other test substances despite their low total Zn content. Environ Toxicol Chem 2017;36:3324-3332. © 2017 Crown in the Right of Canada. Published by Wiley Periodicals Inc. on behalf of SETAC., (© 2017 Crown in the Right of Canada. Published by Wiley Periodicals Inc. on behalf of SETAC.)

We present a straightforward and efficient method to reduce the mode spacing of a frequency comb based on binary pseudo-random phase modulation of its pulse train. As a proof of concept, we use such a densified comb to perform dual-comb spectroscopy of a long-delay Mach-Zehnder interferometer and a high-quality-factor microresonator with sub-MHz spectral sampling. Since this approach is based on binary phase modulation, it combines all the advantages of other densification techniques: simplicity, single-step implementation, and conservation of the initial comb's power.

Background: Bedside ultrasound technology is an innovative, cost-effective, safe, and reproducible method used to make efficient decisions that directly affect the care of critical care patients., Purpose: To validate the use of ultrasound technology when compared with the use of standard chest radiography for the detection of pneumothorax following chest tube removal., Methods: A prospective observational comparison study of 50 cardiothoracic patients with surgically placed pleural chest tubes was conducted. The accuracy of bedside ultrasound technology was compared with standard chest radiography to detect pneumothorax., Results: The sample kappa statistic was 1.000, indicating a perfect agreement between bedside ultrasonography and chest radiography in the detection of pneumothorax. Completion of the bedside ultrasound procedure took significantly less time than chest radiography., Conclusions: Bedside ultrasound technology is as accurate as chest radiography in detecting pneumothorax following chest tube removal and can save institutions' time and money.

Although two hepatic sterol metabolites, 24(S)-hydroxycholesterol and 24(S),25-epoxycholesterol, are thought to be important regulators of cholesterol biosynthesis, nothing is known of their degradation and disposal in liver, nor of the mechanisms that regulate their levels. As an initial approach to these questions the two sterols were administered intragastrically, as a bolus, to mice and their hepatic accumulation and conversion to more polar compounds were examined as a function of time. These results were compared to those obtained for cholesterol and for the unnatural epimer of one of the oxysterols, 24(R)-hydroxycholesterol. Maximum concentrations of the three oxysterols in liver were reached by approx. 4 h and then declined to control levels by 8 h. More polar neutral and acidic metabolites were found in the liver extracts. Radiolabeled oxysterols and their metabolites were found in bile glands. In comparison, the amounts of hepatic free and esterified cholesterol and of acidic products formed from it increased gradually over the measured period of time. Rates of conversion of the two 24-hydroxycholesterol epimers into acidic compounds by a liver mitochondrial fraction in vitro exceeded those of 24(S),25-epoxycholesterol and cholesterol. 24(S)-Hydroxycholesterol did not lower the level of hepatic HMG-CoA reductase activity, consistent with the absence of any significant accumulation of the free sterol. Accumulation of appreciable amounts of free 24(S),25-epoxycholesterol was associated with lowered levels of reductase. The existence of hepatic systems for the rapid inactivation and degradation of the oxysterols is consistent with their postulated role in the regulation of cholesterol synthesis.

In order to determine whether hydration of the delta 24 bond of desmosterol contributes to the formation of the regulatory oxysterol, 25-hydroxycholesterol, [3H]desmosterol was incubated with two cultured cell lines and the labeled products were analyzed. Small amounts of 25-hydroxycholesterol were formed with Chinese hamster lung (Dede) cell cultures, but not with mouse fibroblast (L) cell cultures. Apparently, desmosterol was converted into cholesterol, a process that does not occur in L cells, before 25-hydroxycholesterol takes place. No reliable evidence could be obtained for hydration of the delta 24 bond or for the reverse reaction upon incubation of [3H]25-hydroxycholesterol. Oxygenation of desmosterol occurred in both Dede and L cell cultures to give a mixture of 24(R)- and 24(S)-25-epoxy-cholesterol. This reaction, along with the production of 7-oxygenated sterols, may account for low levels of HMG-CoA reductase repressor activity previously found to be associated with delta 24 sterols.

Hospital food group purchasing programs face problems that other kinds of group purchasing programs don't have. HARICOMP, a not-for-profit hospital shared services corporation, helped a group of Rhode Island hospitals solve some of these problems by using computers. The computers eliminate much of the time-consuming effort involved in making price comparisons, holding sales meetings, and doing paperwork.

The chemical syntheses of 4,4'-dimethylcholest-5-en-3 beta-ol-7-one, 4,4'-dimethylcholest-5-ene-3 beta, 7 beta-diol and 4,4'-dimethylcholest-5-ene-3 beta, 7 alpha-diol are described. All of these compounds were found to be potent inhibitors of 3-hydroxy-3-methylglutaryl (HMG-CoA) reductase activity in cultured mouse L cells. The synthetic scheme developed in this study utilizes commercial cholesterol as the starting material and provides a simplified method for the preparation of 4,4'-dimethyl-7-oxygenated steroids.

Preincubation of broken cell preparations from a variety of tissues and cell cultures resulted in an apparent increase in the level of 3-hydroxy-3-methylglutaryl-CoA reductase activity. However, apparent activation of the reductase in mouse liver, hepatomas and primary liver cell cultures was attributed largely to the loss, during the preincubation period, of an interfering enzyme, 3-hydroxy-3-methylglutaryl-CoA lyase. Among non hepatic cells and tissues (which did not contain appreciable lyase activity) the proportion of latent reductase was high in sonicates of fetal brain and in L cells and was independent of the level of total enzyme activity present. Activation of the reductase was blocked by hydroxymethylglutaryl-CoA and NADPH as well as by KF so that activation did not occur under the conditions of the enzyme assay. The enzyme was activated slowly at 4 degrees C, so that partial activation of the latent form occurred during isolation of the microsomal fraction by differential centrifugation. The reductase present in sonicates of cells with either a high or low proportion of the latent enzyme was inactivated by incubation with ATP and Mg2+. Suppression of reductase activity in L cell cultures by treatment with 25-hydroxycholesterol and an age-related decline in brain enzyme activity did not involve reversible conversion of the reductase to an inactive form.