One‐step and sequential SARSCOV‐2 polymerase chain reaction tests would not work every time

IntroductionRT‐PCR is widely used as a diagnostic test for the detection of SARS‐CoV‐2. In this study, we aim to describe the clinical utility of serial PCR testing in the final detection of COVID‐19.MethodWe collected multiple nasopharyngeal swab samples from patients who had negative RT‐PCR test on the first day after hospitalization. RT‐PCR tests were performed on the second day for all patients with initial negative result. For the patients with secondary negative results on day 2, tertiary RT‐PCR tests were performed on day 3 after hospitalization.ResultAmong 68 patients with initial negative test results, at the end of follow‐up, the mortality number was 20 (29.4%). About 33.8% of patients had subsequent positive PCR test results for the second time and 17.4% of the patients who performed third PCR test had positive result.ConclusionBased on this study, serial RT‐PCR testing is unlikely to yield additional information.     

A Combination of Constitutive Damage Model and Artificial Neural Networks to Characterize the Mechanical Properties of the Healthy and Atherosclerotic Human Coronary Arteries

It has been indicated that the content and structure of the elastin and collagen of the arterial wall can subject to a significant alteration due to the atherosclerosis. Consequently, a high tissue stiffness, stress, and even damage/rupture are triggered in the arterial wall. Although many studies so far have been conducted to quantify the mechanical properties of the coronary arteries, none of them consider the role of collagen damage of the healthy and atherosclerotic human coronary arterial walls. Recently, a fiber family‐based constitutive equation was proposed to capture the anisotropic mechanical response of the healthy and atherosclerotic human coronary arteries via both the histostructural and uniaxial data. In this study, experimental mechanical measurements along with histological data of the healthy and atherosclerotic arterial walls were employed to determine the constitutive damage parameters and remodeling of the collagen fibers. To do this, the preconditioned arterial tissues were excised from human cadavers within 5‐h postmortem, and the mean angle of their collagen fibers was precisely determined. Thereafter, a group of quasistatic axial and circumferential loadings were applied to the arterial walls, and the constrained nonlinear minimization method was employed to identify the arterial parameters according to the axial and circumferential extension data. The remodeling of the collagen fibers during the tensile test was also predicted via Artificial Neural Networks algorithm. Regardless of loading direction, the results presented a noteworthy load‐bearing capability and stiffness of the atherosclerotic arteries compared to the healthy ones (P < 0.005). Theoretical fiber angles were found to be consistent with the experimental histological data with less than 2 and 5° difference for the healthy and atherosclerotic arterial walls, respectively. The pseudoelastic damage model data were also compared with that of the experimental data, and interestingly, the arterial mechanical behavior for both the primary loading (up to the elastic region) and the discontinuous softening (up to the ultimate stress) was well addressed. The proposed model predicted well the mechanical response of the arterial tissue considering the damage of collagen fibers for both the healthy and atherosclerotic arterial walls.     

Post‐COVID‐19 maxillary osteonecrosis and floating maxillary teeth due to mucormycosis in two uncontrolled diabetic patients

Mucormycosis is a rare, invasive, quickly progressing fungal infection that generally affects patients who are immunocompromised. If left untreated, the disease is characterized by progressive necrosis and is often fatal. We present two cases of post‐COVID‐19 mucormycosis with a history of several years of uncontrolled diabetic mellitus.     

If I am not for myself,who is for me? The experiences of older migrant home care recipients during their hospitalization

Objective: Hospitalization is a major risk for older adults; therefore, it is crucial to provide the appropriate treatment during hospitalization. This study examined hospitalized older adults’ perceptions regarding three groups of treatment providers: nursing staff, family members, migrant home care workers.

Method: Qualitative interviews were conducted with 17 hospitalized older adults. Data were gathered by in-depth interviews. Content analysis included open coding, axial coding and integration of the main findings using constant comparisons.

Results: Three themes emerged: (1) ‘What is my worth?’ This theme was focused on the participants’ perceptions of themselves as helpless and dependent on others. (2) ‘What would I do without them?’ This theme referred to the perception of the migrant home care workers and nursing staff as essential. It meant immense gratitude, but also a sense of dependency on paid caregivers. (3) ‘They have their own busy life.’ This theme concerned participants’ low treatment expectations from their family members due to their perception of their family members as having multiple obligations.

Conclusion: Hospitalized older adults prefer to turn to paid caregivers rather than to their families. Findings are discussed in light of the tension between formal and informal care in countries that are transitioning from traditional family values to modern values, placing the care of older adults by paid caregivers.     

Unusual mid‐shaft fractures during long‐term bisphosphonate therapy

Background Bisphosphonates are the most commonly prescribed medications for the treatment of osteoporosis. Although existing evidence supports a good safety profile, there is concern that chronic administration of these agents could result in severe suppression of bone turnover with increased risk of nonvertebral fractures. Objective The objective of this study was to report the clinical presentation, selected bone histomorphometry and X‐ray images of patients who developed mid‐shaft long bone fractures during bisphosphonate therapy, six of whom had bone biopsy for histomorphometery. Results Of the 13 patients who sustained atraumatic mid‐shaft fractures, 10 were on alendronate and three were on risedronate therapy before the fractures. In addition to bisphosphonates, three patients were on oestrogen and two on tamoxifen concomitantly. Four patients with glucocorticoid‐induced osteoporosis were on alendronate for 3–11 years along with glucocorticoid therapy. Bone histomorphometry showed severe suppression of bone turnover in five patients and low bone turnover in one patient. Conclusion Long‐term bisphosphonate therapy may increase the risk of unusual long bone mid‐shaft fractures. This is probably due to prolonged suppression of bone turnover, which could lead to accumulation of microdamage and development of hypermineralized bone. At present, the scope of this complication in the larger context of patients receiving bisphosphonate therapy remains unknown, but appears to be small.