There is concern that antidiabetic incretin-based drugs, including dipeptidyl peptidase 4 (DPP-4) inhibitors and glucagon-like peptide 1 (GLP-1) analogues, can increase the risk of heart failure. ...Ongoing clinical trials may not have large enough samples to effectively address this issue.
We applied a common protocol in the analysis of multiple cohorts of patients with diabetes. We used health care data from four Canadian provinces, the United States, and the United Kingdom. With the use of a nested case-control analysis, we matched each patient who was hospitalized for heart failure with up to 20 controls from the same cohort; matching was based on sex, age, cohort-entry date, duration of treated diabetes, and follow-up time. Cohort-specific hazard ratios for hospitalization due to heart failure among patients receiving incretin-based drugs, as compared with those receiving oral antidiabetic-drug combinations, were estimated by means of conditional logistic regression and pooled across cohorts with the use of random-effects models.
The cohorts included a total of 1,499,650 patients, with 29,741 hospitalized for heart failure (incidence rate, 9.2 events per 1000 persons per year). The rate of hospitalization for heart failure did not increase with the use of incretin-based drugs as compared with oral antidiabetic-drug combinations among patients with a history of heart failure (hazard ratio, 0.86; 95% confidence interval CI, 0.62 to 1.19) or among those without a history of heart failure (hazard ratio, 0.82; 95% CI, 0.67 to 1.00). The results were similar for DPP-4 inhibitors and GLP-1 analogues.
In this analysis of data from large cohorts of patients with diabetes, incretin-based drugs were not associated with an increased risk of hospitalization for heart failure, as compared with commonly used combinations of oral antidiabetic drugs. (Funded by the Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT02456428.).
Based on existing data and previous work, a series of studies is proposed as a basis toward a pragmatic early step in transforming toxicity testing. These studies were assembled into a data-driven ...framework that invokes successive tiers of testing with margin of exposure (MOE) as the primary metric. The first tier of the framework integrates data from high-throughput in vitro assays, in vitro-to-in vivo extrapolation (IVIVE) pharmacokinetic modeling, and exposure modeling. The in vitro assays are used to separate chemicals based on their relative selectivity in interacting with biological targets and identify the concentration at which these interactions occur. The IVIVE modeling converts in vitro concentrations into external dose for calculation of the point of departure (POD) and comparisons to human exposure estimates to yield a MOE. The second tier involves short-term in vivo studies, expanded pharmacokinetic evaluations, and refined human exposure estimates. The results from the second tier studies provide more accurate estimates of the POD and the MOE. The third tier contains the traditional animal studies currently used to assess chemical safety. In each tier, the POD for selective chemicals is based primarily on endpoints associated with a proposed mode of action, whereas the POD for nonselective chemicals is based on potential biological perturbation. Based on the MOE, a significant percentage of chemicals evaluated in the first 2 tiers could be eliminated from further testing. The framework provides a risk-based and animal-sparing approach to evaluate chemical safety, drawing broadly from previous experience but incorporating technological advances to increase efficiency.
The quality of images from an infrared (IR) microscope has traditionally been limited by considerations of throughput and signal-to-noise ratio (SNR). An understanding of the achievable quality as a ...function of instrument parameters, from first principals is needed for improved instrument design. Here, we first present a model for light propagation through an IR spectroscopic imaging system based on scalar wave theory. The model analytically describes the propagation of light along the entire beam path from the source to the detector. The effect of various optical elements and the sample in the microscope is understood in terms of the accessible spatial frequencies by using a Fourier optics approach and simulations are conducted to gain insights into spectroscopic image formation. The optimal pixel size at the sample plane is calculated and shown much smaller than that in current mid-IR microscopy systems. A commercial imaging system is modified, and experimental data are presented to demonstrate the validity of the developed model. Building on this validated theoretical foundation, an optimal sampling configuration is set up. Acquired data were of high spatial quality but, as expected, of poorer SNR. Signal processing approaches were implemented to improve the spectral SNR. The resulting data demonstrated the ability to perform high-definition IR imaging in the laboratory by using minimally-modified commercial instruments.
Throughout the animal kingdom, adaptive colouration serves critical functions ranging from inconspicuous camouflage to ostentatious sexual display, and can provide important information about the ...environment and biology of a particular organism. The most ubiquitous and abundant pigment, melanin, also has a diverse range of non-visual roles, including thermoregulation in ectotherms. However, little is known about the functional evolution of this important biochrome through deep time, owing to our limited ability to unambiguously identify traces of it in the fossil record. Here we present direct chemical evidence of pigmentation in fossilized skin, from three distantly related marine reptiles: a leatherback turtle, a mosasaur and an ichthyosaur. We demonstrate that dark traces of soft tissue in these fossils are dominated by molecularly preserved eumelanin, in intimate association with fossilized melanosomes. In addition, we suggest that contrary to the countershading of many pelagic animals, at least some ichthyosaurs were uniformly dark-coloured in life. Our analyses expand current knowledge of pigmentation in fossil integument beyond that of feathers, allowing for the reconstruction of colour over much greater ranges of extinct taxa and anatomy. In turn, our results provide evidence of convergent melanism in three disparate lineages of secondarily aquatic tetrapods. Based on extant marine analogues, we propose that the benefits of thermoregulation and/or crypsis are likely to have contributed to this melanisation, with the former having implications for the ability of each group to exploit cold environments.
Although severe coronavirus disease 2019 (COVID-19) and hospitalization associated with COVID-19 are generally preventable among healthy vaccine recipients, patients with immunosuppression have poor ...immunogenic responses to COVID-19 vaccines and remain at high risk of infection with SARS-CoV-2 and hospitalization. In addition, monoclonal antibody therapy is limited by the emergence of novel SARS-CoV-2 variants that have serially escaped neutralization. In this context, there is interest in understanding the clinical benefit associated with COVID-19 convalescent plasma collected from persons who have been both naturally infected with SARS-CoV-2 and vaccinated against SARS-CoV-2 ("vax-plasma"). Thus, we report the clinical outcome of 386 immunocompromised outpatients who were diagnosed with COVID-19 and who received contemporary COVID-19-specific therapeutics (standard-of-care group) and a subgroup who also received concomitant treatment with very high titer COVID-19 convalescent plasma (vax-plasma group) with a specific focus on hospitalization rates. The overall hospitalization rate was 2.2% (5 of 225 patients) in the vax-plasma group and 6.2% (10 of 161 patients) in the standard-of-care group, which corresponded to a relative risk reduction of 65% (
= 0.046). Evidence of efficacy in nonvaccinated patients cannot be inferred from these data because 94% (361 of 386 patients) of patients were vaccinated. In vaccinated patients with immunosuppression and COVID-19, the addition of vax-plasma or very high titer COVID-19 convalescent plasma to COVID-19-specific therapies reduced the risk of disease progression leading to hospitalization.IMPORTANCEAs SARS-CoV-2 evolves, new variants of concern (VOCs) have emerged that evade available anti-spike monoclonal antibodies, particularly among immunosuppressed patients. However, high-titer COVID-19 convalescent plasma continues to be effective against VOCs because of its broad-spectrum immunomodulatory properties. Thus, we report clinical outcomes of 386 immunocompromised outpatients who were treated with COVID-19-specific therapeutics and a subgroup also treated with vaccine-boosted convalescent plasma. We found that the administration of vaccine-boosted convalescent plasma was associated with a significantly decreased incidence of hospitalization among immunocompromised COVID-19 outpatients. Our data add to the contemporary data providing evidence to support the clinical utility of high-titer convalescent plasma as antibody replacement therapy in immunocompromised patients.
Previous studies have found that depression predicts all-cause mortality in heart failure (HF), but little is known about its effect on long-term survival. This study examined the effects of ...depression on long-term survival in patients with HF.
Patients hospitalized with HF (n = 662) at an urban academic medical center were enrolled in a prospective cohort study between January 1994 and July 1999. Depression was assessed on a structured interview during the index hospitalization and on quarterly interviews for 1 year after discharge. Patients were classified at index as having Diagnostic and Statistical Manual, Fourth Edition major depressive disorder (n = 131), minor depression (n = 106), or no depression (n = 425). Clinical data and the National Death Index were used to identify date of death or last known contact through December 19, 2014, up to 20 years after the index hospitalization. The main outcome was time from enrollment to death from any cause.
A total of 617 (94.1%) patients died during the follow-up period. Major depressive disorder was associated with higher all-cause mortality compared with no depression (adjusted hazard ratio = 1.64, 95% confidence interval = 1.27-2.11, p = .0001). This association was stronger than that of any of the established predictors of mortality that were included in the fully adjusted model. Patients with persistent or worsening depressive symptoms during the year after discharge were at greatest risk for death. The association between minor depression and survival was not significant.
Major depression is an independent risk factor for all-cause mortality in patients with HF. Its effect persists for many years after the diagnosis of depression.
The radiologic diagnosis of adrenal disease can be challenging in settings of atypical presentations, mimics of benign and malignant adrenal masses, and rare adrenal anomalies. Misdiagnosis may lead ...to suboptimal management and adverse outcomes. Adrenal adenoma is the most common benign adrenal tumor that arises from the cortex, whereas adrenocortical carcinoma (ACC) is a rare malignant tumor of the cortex. Adrenal cyst and myelolipoma are other benign adrenal lesions and are characterized by their fluid and fat content, respectively. Pheochromocytoma is a rare neuroendocrine tumor of the adrenal medulla. Metastases to the adrenal glands are the most common malignant adrenal tumors. While many of these masses have classic imaging appearances, considerable overlap exists between benign and malignant lesions and can pose a diagnostic challenge. Atypical adrenal adenomas include those that are lipid poor; contain macroscopic fat, hemorrhage, and/or iron; are heterogeneous and/or large; and demonstrate growth. Heterogeneous adrenal adenomas may mimic ACC, metastasis, or pheochromocytoma, particularly when they are 4 cm or larger, whereas smaller versions of ACC, metastasis, and pheochromocytoma and those with washout greater than 60% may mimic adenoma. Because of its nonenhanced CT attenuation of less than or equal to 10 HU, a lipid-rich adrenal adenoma may be mimicked by a benign adrenal cyst, or it may be mimicked by a tumor with central cystic and/or necrotic change such as ACC, pheochromocytoma, or metastasis. Rare adrenal tumors such as hemangioma, ganglioneuroma, and oncocytoma also may mimic adrenal adenoma, ACC, metastasis, and pheochromocytoma. The authors describe cases of adrenal neoplasms that they have encountered in clinical practice and presented to adrenal multidisciplinary tumor boards. Key lessons to aid in diagnosis and further guide appropriate management are provided.
RSNA, 2023
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Abstract
The purpose of this work is to identify and synthesize research produced since the second edition of these Guidelines was published and incorporate new results into revised evidence-based ...recommendations for the treatment of severe traumatic brain injury in pediatric patients. This document provides an overview of our process, lists the new research added, and includes the revised recommendations. Recommendations are only provided when there is supporting evidence. This update includes 22 recommendations, 9 are new or revised from previous editions. New recommendations on neuroimaging, hyperosmolar therapy, analgesics and sedatives, seizure prophylaxis, temperature control/hypothermia, and nutrition are provided. None are level I, 3 are level II, and 19 are level III. The Clinical Investigators responsible for these Guidelines also created a companion algorithm that supplements the recommendations with expert consensus where evidence is not available and organizes possible interventions into first and second tier utilization. The complete guideline document and supplemental appendices are available electronically (https://doi.org/10.1097/PCC.0000000000001735). The online documents contain summaries and evaluations of all the studies considered, including those from prior editions, and more detailed information on our methodology. New level II and level III evidence-based recommendations and an algorithm provide additional guidance for the development of local protocols to treat pediatric patients with severe traumatic brain injury. Our intention is to identify and institute a sustainable process to update these Guidelines as new evidence becomes available.
Purpose
To describe the appearance of chronically hemorrhagic adenomas on adrenal protocol CT and correlate imaging with pathologic findings.
Methods
Retrospective case series of adult patients with ...resected adrenal adenomas showing internal hemorrhage at histology. Seven of nine patients underwent pre-operative adrenal protocol CT and 2/7 underwent unenhanced CT with portal venous phase CT. Two abdominal radiologists in consensus assessed the CT images for the presence of calcifications, macroscopic fat, cystic/necrotic appearance, and the presence, pattern, and percent nodule volume of areas < 10 HU on unenhanced CT. Absolute washout was calculated using a large ROI, and ROIs on the highest and lowest attenuating regions on the portal venous phase.
Results
Mean adenoma length was 4.9 cm. All adenomas had areas measuring < 10 HU on unenhanced CT, ranging from < 20 to > 80% nodule volume. Calcifications were present in 4/9 adenomas and gross fat in 4/9 on CT. Of the seven cases with adrenal protocol CT, the absolute washout was < 60% in 5/7 using the large ROI, 5/7 using the low attenuation ROI, and 7/7 using the high attenuation ROI. At histology, all nine cases had microscopic evidence of hemorrhage, lipid rich adenoma cells, and fibrosclerosis. Myelolipomatous changes were identified in 4/9 cases, with the remaining five cases showing lipomatous metaplasia without a myeloid component.
Conclusion
Chronically hemorrhagic adrenal adenomas demonstrated variable areas < 10 HU on unenhanced CT corresponding to lipid rich adenoma cells. Absolute washout was most often < 60%, hypothesized to be due to fibrosclerosis within the adenomas.
Ethyl formate is very effective for the formylation of amines and diamines to yield formamides and diformamides, respectively. Subsequent dehydrogenation of 1:1 mixtures of formamides and amines or ...diformamides and diamines with ruthenium pincer catalysts furnishes ureas and polyureas, respectively. This approach provides access to a large structural variety of ureas and polyureas because a wide range of primary amines and diamines are readily converted to the corresponding ureas and polyureas. Small molecule ureas were isolated in yields of up to 95%, whereas polyureas were isolated in lower yields (up to 68%) due to strong adhesion to the reaction flask and poor solubility impeding product removal. Furthermore, the ease with which hydrogen can be removed from the reaction medium enables the synthesis of polyureas with molecular weights that are among the highest reported to date (Mn up to 31,100 g mol−1). Notably, this synthetic approach does not necessitate high pressure conditions, simplifying equipment needed for their preparation, and it avoids the use of isocyanates, which have significant health concerns.
The table of contents entry: Ethyl formate effectively formylates amines and diamines. Ruthenium pincer complexes dehydrogenatively couple the resulting formamides and diformamides with amines and diamines to produce ureas and polyureas, respectively (with Mn values up to 31,100 g mol−1) in good yields.