Bidirectional Iterative Approach to Sequence-Defined Unsaturated Oligoesters.

Herein, we describe the development of a new strategy for the synthesis of unsaturated oligoesters via sequential metal- and reagent-free insertion of vinyl sulfoxonium ylides into the O-H bond of carboxylic acid. Like two directional coupling of amino acids (N- to C-terminal and C- to N-terminal) in peptide synthesis, the present approach offers a strategy in both directions to synthesize oligoesters. The sequential addition of the vinyl sulfoxonium ylide to the carboxylic acids (acid iteration sequence) in one direction and the sequential addition of the carboxylic acids to the vinyl sulfoxonium ylide (ylide iteration sequence) in another direction yield (Z)-configured unsaturated oligoesters. To perform this iteration, we have developed a highly regioselective insertion of vinyl sulfoxonium ylide into the X-H (X = O, N, C, S, halogen) bond of acids, thiols, phenols, amines, indoles, and halogen acids under metal-free reaction conditions. The insertion reaction is applied to a broad range of substrates (>50 examples, up to 99% yield) and eight iterative sequences. Mechanistic studies suggest that the rate-limiting step depends on the type of X-H insertion.

COVID-19 Isolation and Quarantine Guidelines for Older Adults in Nursing Homes.

The COVID-19 pandemic poses an ever-increasing threat to older Americans, especially those in nursing homes. The compact nature of these facilities and the morbidities shared by this population make them susceptible to the virus and its symptoms. Because of this, the CDC has published guidelines directed at isolation and quarantine measures specifically created to protect this patient population. These measures are comprehensive and provide examples and management of situations, such as admissions and outbreaks, that these facilities must deal with and be ready to face on a regular basis. In this review, we discuss the guidelines for isolation and quarantine as it pertains to the nursing home population, and some of the unintended effects these protocols may have on this population.

Use of liothyronine (L-T3) as an augmentation therapy for depression during pregnancy.

The thyroid hormone triiodothyronine (T3) can be used as an augmentation therapy for depression. This case involves a patient who had been initiated on liothyronine (L-T3) for this purpose and subsequently became pregnant. The exogenous T3 affected maternal thyroid hormone production, including suppression of her thyroxine (T4) levels. In pregnancy, maternal T4 is important for fetal neurodevelopment. Accordingly, use of exogenous T3 for adjunct treatment of depression in pregnant patients or those planning pregnancy requires careful laboratory monitoring of thyroid function tests. In this case, L-T3 was discontinued and the patient was eventually started on levothyroxine (L-T4) and went on to have an uneventful pregnancy.

Chronic kidney disease in type 2 diabetes: Does an abnormal urine albumin-to-creatinine ratio need to be retested?

OBJECTIVE: To determine the positive predictive value (PPV) of a single random abnormal urine albumin-to-creatinine ratio (ACR) compared with repeat test results in patients with type 2 diabetes to diagnose chronic kidney disease (CKD). DESIGN: Retrospective, longitudinal secondary data analysis using Calgary Laboratory Services data. SETTING: Calgary, Alta. PARTICIPANTS: Patients aged 21 and older with a new diagnosis of diabetes in the study period from January 2008 to December 2015 and with a first abnormal urine ACR followed by another ACR test completed within 120 days. MAIN OUTCOME MEASURES: The PPV of an abnormal urine ACR (2 to 20 mg/mmol) to diagnose CKD was calculated. A test result was considered a true positive if a subsequent positive test result (≥ 2 mg/mmol) was identified within 120 days of the first positive test result and a false positive if 2 subsequent negative test results were identified within the same time period. The relationship between the first and second urine ACR values to assess the probability of the second urine ACR being abnormal (≥ 2 mg/mmol) based on the values of the first abnormal urine ACR was also explored. RESULTS: The PPV of the first abnormal urine ACR between 2 and 20 mg/mmol to diagnose CKD was calculated at 96.80% (95% CI 95.37% to 98.21%). Additionally, there was increased predictive probability of the second urine ACR being abnormal at higher values of the first urine ACR (2 to 20 mg/mmol). The data were further analyzed to exclude test results with a new or changed prescription of angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker medications around the time of the first urine ACR test to focus results on screening and not treatment response. With these exclusions, the PPV for first urine ACR between 2 and 20 mg/mmol to diagnose CKD was calculated as 96.23% (95% CI 94.13% to 98.32%). CONCLUSION: The first random abnormal urine ACR has a good PPV for the diagnosis of CKD in patients with type 2 diabetes, so multiple random urine ACR tests might not be necessary to diagnose patients with type 2 diabetes as having persistent microalbuminuria and CKD. A simpler diagnostic model for diagnosing renal disease might improve patient compliance, efficiency of testing, and implementation of health interventions. Reduced testing would also be expected to result in reduced cost from a health care expenditure perspective.

Web-Based Interventions for Chronic Back Pain: A Systematic Review.

BACKGROUND: Chronic low back pain is one of the most common presenting complaints to a physician's office. Treatment is often challenging and recovery depends on various factors, often resulting in significant investments of time and resources. OBJECTIVE: The aim of this review is to determine which Web-based interventions aimed at chronic low back pain are of benefit to patients. METHODS: Randomized controlled trials (RCTs) studying Web-based interventions directed at adults with chronic low back pain were included. Retrospective studies, narrative reviews, nonrandomized trials, and observational studies were excluded. Electronic databases and bibliographies were searched. RESULTS: In total, nine unique RCTs were identified (total participants=1796). The number of patients randomized in each trial ranged from 51 to 580. Four trials studied online cognitive behavioral therapy (CBT) and five trials studied other Web-based interventions with interactive features. Empowerment/control was improved in six studies. Use of CBT was associated with reduced catastrophization among patients. Mixed results were reported with regards to reduction in pain levels and disability, although some studies showed promise in reducing disability in the short term. One study that measured health care utilization reported reduced utilization with the use of moderated email discussion. CONCLUSIONS: Limited data are available regarding effective Web-based interventions to improve outcomes for patients with chronic low back pain. Nine RCTs with small sample sizes were identified in this review. Online CBT appears to show some promise in terms of reducing catastrophization and improving patient attitudes. Further research in this area with larger-scale studies focusing on appropriate outcomes appears to be a priority.