Heart rate variability features for different stress classification.

AIM: Autonomic nervous system (ANS) activities during different types of stress could affect the electrocardiogram (ECG) signal. This study aimed to recognize the types of stress by using different ECG signals in order to prevent its actual physiological effects on the heart signal. METHOD: The ECG signal recorded by portable wrist bracelets from 20 students in during seven phases which incorporated three different types of stress and four relaxation phases. After different forms of windowing the signal, we used linear and non-linear features such as detrended fluctuation analysis (DFA), Poincaré plot, approximate and sample entropy, correlation dimension, and recurrence plot to extract various features of the heart rate variability (HRV). Then, different classifiers were used to identify the types of stress. RESULTS: The results showed a decrease in NN50, RMSSD, pNN50, and recurrence plot features, and an increase in the DFA method during stress stages, which show the effect of stress on heart rate. Also, by using the convolutional neural network (CNN), an average classification rate of 98 % was obtained in association with cognitive stress and that of 94.5 % in association with emotional stress. CONCLUSION: This paper showed that features extracted from HRV can detect the stress and non-stress stages with high significance. Also, the accuracy of this paper proved that the proposed method is successful in preventing the dangerous effects of different types of stress on the heart (Tab. 5, Fig. 6, Ref. 34). Text in PDF www.elis.sk Keywords: stress, heart rate variability, non-linear features, convolutional neural network, classification.

Hamartoma of the breast in a man: first case report.

Mammary hamartomas were reported in 0.7% of all benign tumors of the female breast. Histologically breast hamartomas contain lobular breast tissue with various degrees of fibrous, fibrocystic, and adipose tissue. Rare types include muscular (myoid) and cartilage (chondroid) hamartomas. We report a case of muscular hamartoma in a man. A 36-year-old man was admitted to the psychiatric unit with the diagnosis of schizophrenia. The patient complained of a slowly growing mass in his left breast. He denied any discharge from the nipple, but he complained of itching. A 2 cm x 3 cm nontender mass was palpable. There was no evidence of axillary lymphadenopathy. A needle aspiration was nondiagnostic. The excisional biopsy specimen revealed fatty tissue which was edematous and hemorrhagic. Microscopically it showed multiple bundles of muscles organized randomly. Myoid hamartoma was the diagnosis. Mammary hamartoma is considered a female tumor exclusively. Myoid hamartoma has been reported previously in 25 women. We report a myoid hamartoma in a man and, to our knowledge, it is the first and only such case to be reported.

CD15(+) acute lymphoblastic leukemia and subsequent monoblastic leukemia: persistence of t(4;11) abnormality and B-cell gene rearrangement.

The abnormality in the translocation of chromosomes 4 and 11 (t[4;11]) has been characteristically associated with calla-negative CD15(+) acute lymphoblastic leukemia (ALL) of early pre-B-cell origin. Transformation of a lymphoblastoid to a monoblastoid morphologic structure has rarely been described at relapse in these cases; however, these cases have lacked flow cytometric immunophenotyping (FCI) and genotypic studies (GS) to define the immunophenotype of and the presence of a B-cell gene rearrangement in the monoblastoid component. We report a case of CD15(+), CD10(-) ALL of early pre-B-cell origin defined by morphologic testing and FCI with the t(4;11) abnormality. At relapse, the morphologic testing, enzyme cytochemistry, and FCI data were characteristic of monoblastic leukemia. The t(4;11) abnormality persisted with associated additional chromosomal abnormalities, and the monoblasts contained a B-cell gene rearrangement by GS. These findings support the concept that both processes arose from a multipotential progenitor cell.