Hyperthyroidism and the management of atrial fibrillation.

Atrial fibrillation is often induced in patients with hyperthyroidism and may trigger heart failure. Its prevalence and outcome were examined to obtain up-to-date information. Persistent atrial fibrillation was observed in approximately 1.7% of new hyperthyroid patients. It occurs more frequently in males (2.86%) than in females (1.36%), even though the number of male hyperthyroid patients is only one fifth of female patients. The rate increased with age, being 8% in the patients older than 70 years old. The initial treatment is to control the heart rate with routine pharmacologic therapy and to start antithyroid therapy as quickly as possible. Attempted cardioversion should be deferred until approximately the fourth month of maintaining a euthyroid state, because more than 56% of atrial fibrillation spontaneously reverts to sinus rhythm when the thyroid hormone levels start to decline. Elective cardioversion for those whose atrial fibrillation persists is highly effective and sinus rhythm maintenance rates were 56.7% and 47.6% at the 10th and the 14th year, respectively, even though the duration of atrial fibrillation prior to cardioversion was extremely long (35.0 +/- 29.0 months).     

Isolation of a somatic-cell mutant defective in phosphatidylserine biosynthesis.

Mutant clones of Chinese hamster ovary (CHO) cells defective in the base-exchange reaction of phospholipids with choline were isolated by using an in situ enzymatic assay for the reaction in cell colonies immobilized on polyester cloth. The specific activities of the choline-exchange reaction in extracts of one of the mutants (designated 64) grown at 33 degrees C and 40 degrees C were 13% and 6% of those in parental (CHO-K1) cells, respectively. The choline-exchange activity in the mutant was more thermolabile in cell extracts than that in the parent, suggesting that a mutation in the structural gene for the choline-exchange enzyme might have been induced in this mutant. In culture medium supplemented with lipoprotein-deficient serum, mutant 64 grew almost normally at 33 degrees C but divided only twice at 40 degrees C and then stopped growing. Labeling of intact cells with [32P]Pi showed that mutant 64 was also strikingly defective in the biosynthesis of phosphatidylserine at 40 degrees C but was normal at 33 degrees C. Most temperature-resistant revertants of mutant 64 exhibited nearly normal ability to synthesize phosphatidylserine at 40 degrees C and also showed choline-exchange activity similar to that in parental cells. The addition of phosphatidylserine to medium supplemented with newborn calf serum, in which mutant 64 grew more slowly than parental cells at 40 degrees C, restored the growth rate of the mutant to the parental level. Our findings suggest that the choline-exchange enzyme functions as the major route for the formation of phosphatidylserine and that the temperature-sensitive growth of mutant 64 is due to a defect in phosphatidylserine biosynthesis at 40 degrees C.     

Interleukin‐8‐producing primary cardiac undifferentiated sarcoma in a child with sustained fever

We report the case of a 12‐year‐old boy with primary undifferentiated sarcoma of the left atrium. He had sustained fever during the clinical course and multiple lung and brain metastases. Chemotherapy and irradiation were ineffective; he died 41 days after hospitalization. On retrospective analysis, interleukin‐8 (IL‐8) was elevated; this was supported by immunohistochemistry and gene expression analysis of tumor samples. IL‐8 continued to increase with tumor progression accompanied by elevated neutrophil count and C‐reactive protein. IL‐8 is involved in malignant tumor proliferation, migration, and angiogenesis and may have been related to the clinical condition and prognosis in the present case.     

Outcomes of Patients With Syncope and Suspected Dementia

Objectives

Syncope and near‐syncope are common in patients with dementia and a leading cause of emergency department (ED) evaluation and subsequent hospitalization. The objective of this study was to describe the clinical trajectory and short‐term outcomes of patients who presented to the ED with syncope or near‐syncope and were assessed by their ED provider to have dementia.

Methods

This multisite prospective cohort study included patients 60 years of age or older who presented to the ED with syncope or near‐syncope between 2013 and 2016. We analyzed a subcohort of 279 patients who were identified by the treating ED provider to have baseline dementia. We collected comprehensive patient‐level, utilization, and outcomes data through interviews, provider surveys, and chart abstraction. Outcome measures included serious conditions related to syncope and death.

Results

Overall, 221 patients (79%) were hospitalized with a median length of stay of 2.1 days. A total of 46 patients (16%) were diagnosed with a serious condition in the ED. Of the 179 hospitalized patients who did not have a serious condition identified in the ED, 14 (7.8%) were subsequently diagnosed with a serious condition during the hospitalization, and an additional 12 patients (6.7%) were diagnosed postdischarge within 30 days of the index ED visit. There were seven deaths (2.5%) overall, none of which were cardiac‐related. No patients who were discharged from the ED died or had a serious condition in the subsequent 30 days.

Conclusions

Patients with perceived dementia who presented to the ED with syncope or near‐syncope were frequently hospitalized. The diagnosis of a serious condition was uncommon if not identified during the initial ED assessment. Given the known iatrogenic risks of hospitalization for patients with dementia, future investigation of the impact of goals of care discussions on reducing potentially preventable, futile, or unwanted hospitalizations while improving goal‐concordant care is warranted.

     

Cancer and non-cancer excess mortality resulting from mixed exposure to polychlorinated biphenyls and polychlorinated dibenzofurans from contaminated rice oil: “<Emphasis Type="Italic">Yusho</Emphasis>”

Purpose

In 1968, rice oil contaminated with polychlorinated biphenyls and polychlorinated dibenzofurans caused a severe outbreak of food poisoning in Japan and was termed locally as “Yusho” (oil disease). In our previous study, we found that area-based standardized mortality ratios (SMRs) of some diseases were elevated shortly after the incident. This previous study, however, was unable to determine whether these elevated SMRs were a result of other area-specific factors. To overcome this limitation, we obtained mortality data from the 5 years before the incident and conducted an area-based study using vital statistics records dating from 1963 to 2002.

Methods

The population of Nagasaki Prefecture was set as the reference population for calculating SMRs. We also included data on cause-specific mortality attributable to cancer and expanded the population to encompass two severely exposed areas where contaminated rice oil was distributed (namely Tamanoura and Naru). We also calculated SMRs in the remainder of the Shimo-Goto region, excluding the exposed area, which was used as a comparison area.

Results

Even after considering the time trends in mortality before the incident, mortality due to diabetes mellitus and heart disease, as well as all-cause mortality, was found to be elevated shortly afterward. Additionally, mortalities due to uterine cancer in Tamanoura and leukemia were also elevated at 30–34 and 10–59 years after the event in both exposed areas, respectively. SMRs for leukemia in Tamanoura were as high as 3.0 (95 % confidence interval 1.4–6.2) and 2.4 (1.2–4.8) 10–19 years later. In this period, SMRs for leukemia in the comparison area were not elevated.

Conclusions

Further epidemiological studies are needed regarding this rice-oil, “Yusho” outbreak, especially with regard to cancer and non-cancer mortality.

     

Withdrawal of repeated morphine enhances histamine-induced scratching responses in mice

An itch is experientially well known that the scratching response of conditions such as atopic dermatitis is enhanced under psychological stress. Morphine is typical narcotic drug that induces a scratching response upon local application as an adverse drug reaction. Although long-term treatment with morphine will cause tolerance and dependence, morphine withdrawal can cause psychologically and physiologically stressful changes in humans. In this study, we evaluated the effects of morphine withdrawal on histamine-induced scratching behavior in mice. Administration of morphine with progressively increasing doses (10–50?mg/kg, i.p.) was performed for 5 consecutive days. At 3, 24, 48, and 72?hr after spontaneous withdrawal from the final morphine dose, histamine was intradermally injected into the rostral part of the back and then the number of bouts of scratching in 60?min was recorded and summed. We found that at 24?hr after morphine withdrawal there was a significant increase in histamine-induced scratching behavior. The spinal c-Fos positive cells were also significantly increased. The relative adrenal weight increased and the relative thymus weight decreased, both significantly. Moreover, the plasma corticosterone levels changed in parallel with the number of scratching bouts. These results suggest that morphine withdrawal induces a stressed state and enhances in histamine-induced scratching behavior. Increased reaction against histamine in the cervical vertebrae will participate in this stress-induced itch enhancement.     

Microvascular resistance in response to iodinated contrast media in normal and functionally impaired kidneys

Contrast‐induced nephropathy (CIN) is considered to result from intrarenal vasoconstriction, and occurs more frequently in impaired than in normal kidneys. It was hypothesized that iodinated contrast media would markedly change renal blood flow and vascular resistance in functionally impaired kidneys. Thirty‐six patients were enrolled (32 men; mean age, 75.3 ± 7.6 years) undergoing diagnostic coronary angiography and were divided into two groups based on the presence of chronic kidney disease (CKD), defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min per 1.73 m² (CKD and non‐CKD groups, n = 18 in both). Average peak velocity (APV) and renal artery resistance index (RI) were measured by Doppler flow wire before and after administration of the iodinated contrast media. The APV and the RI were positively and inversely correlated with the eGFR at baseline, respectively (APV, R = 0.545, P = 0.001; RI, R = ?0.627, P < 0.001). Mean RI was significantly higher (P = 0.015) and APV was significantly lower (P = 0.026) in the CKD than in the non‐CKD group. Both APV (P < 0.001) and RI (P = 0.002) were significantly changed following contrast media administration in the non‐CKD group, but not in the CKD group (APV, P = 0.258; RI, P = 0.707). Although renal arterial resistance was higher in patients with CKD, it was not affected by contrast media administration, suggesting that patients with CKD could have an attenuated response to contrast media.     

Therapeutic Dilemma of Sarcoidosis and Treatment-naïve Hepatitis C Manifesting as Tattoo Reactions

A 23-year-old man had an 8-day history of fatigue and dry cough and papulo-nodular reactions on his extensive tattoos. Chest radiography revealed several small granular shadows, and a transbronchial lung biopsy showed non-caseating epithelioid cell granuloma. A skin biopsy of the tattooed area showed histiocytic infiltrates with phagocytized tattoo pigment. Antibody tests for hepatitis C virus were positive. The patient was successfully treated with corticosteroid therapy, and after inflammation was suppressed, he received delayed anti-viral therapy. Sarcoidosis should be considered as a concurrent condition if papules are presented on the tattoos of patients with hepatitis C.