Cellular diversity of human placental stem villi: an ultrastructural and immunohistochemical study

The aim of the study was to investigate the distribution and differentiation of cell types in the stroma of human placental stem villi (SV). A total of 14 human term placental tissues were studied. Double immunolabeling was performed for desmin-vimentin, desmin--smooth actin and vimentin--smooth actin. Cytokeratin 7, proliferating cell nuclear antigen immunolabeling was also performed. Parallel tissue samples were examined by transmission electron microscopy. HSCORE was performed for the semi-quantitative analysis of distribution of cells in the stroma of SV. Vimentin-labeled cells were mostly distributed in the subtrophoblastic area. Desmin-vimentin double immunolabeling was mainly localized in the triangular area and to a lesser degree in the perivascular area and vessel walls (p=<0.001). However, desmin- smooth actin labeling was observed predominantly in the vessel wall and perivascular area. Vimentin- smooth actin immunoreactivity was significantly stronger in the triangular and perivascular areas compared to the vessel walls (p=0.003).

Ultrastructurally, cells in the stroma of SV were mesenchyme cells, reticulum cells, fibroblasts, myofibroblasts, smooth muscle cells, and Hofbauer cells, filamented and vacuolated cells. The differentiation of myofibroblasts in the triangular and perivascular areas may play a role in maturation of SV and villous contractility, modulation of the intervillous space and this may have effects on maternofetal placental circulation.     

Determining a continuous marker for sleep depth

Detection and quantification of sleep arousals is an important issue, as the frequent arousals are known to reduce the quality of sleep and cause daytime sleepiness. In typical sleep staging, electroencephalograph (EEG) is the core signal and based on the visual inspection of the frequency content of EEG, non-rapid eye movement sleep is staged into four somewhat rough categories. In this study, we aimed at developing a continuous marker based on a more rigorous spectral analysis of EEG to measure or quantify the depth of sleep. In order to develop such a marker, we obtained the time-frequency map of two EEG channels around sleep arousals and identified the frequency bands that show the most change during arousals. We then evaluated classification performance of the potential signals for representing the depth of sleep, using receiver operating characteristic analysis. Our comparisons based on the area under the curve values revealed that the sum of absolute powers in alpha and beta bands is a good continuous marker to represent the depth of sleep. Higher values of this marker indicate low-quality sleep and vice versa. We believe that use of this marker will lead to a better quantification of sleep quality.     

Trunk muscle strength in relation to balance and functional disability in unihemispheric stroke patients

OBJECTIVE: To evaluate trunk muscle strength in unihemispheric stroke patients and to assess how it relates to body balance and functional disability in this patient group. DESIGN: This prospective case-comparison study investigated isometric and isokinetic reciprocal trunk flexion and extension strength at angular velocities in 38 unihemispheric stroke patients and 40 healthy volunteers. The Berg balance scale was used to assess balance and stability, and the FIM instrument was used to evaluate functional disability in the patient group. Patients were evaluated as soon as they were able to stand long enough for testing. RESULTS: Peak torque values for trunk flexion and extension were lower in the stroke patients than in the controls. The differences were significant for trunk flexion and for trunk extension. In both groups, peak torque values for trunk flexors were greater than peak torque values for trunk extensors. There was a significant positive correlation between trunk muscle strength and Berg balance scale score at discharge. Trunk muscle strength was not correlated with FIM total score or FIM motor score, but the locomotion-transfers FIM subscore at discharge was positively correlated with trunk muscle torque values, except for isometric extension. CONCLUSION: The findings indicate trunk flexion and extension muscle weakness in unihemispheric stroke patients, which can interfere with balance, stability, and functional disability.     

Coronary artery thromboembolism: Unexpected presentation of left atrial myxoma covered with thrombus

Cardiac myxomas are benign primer cardiac tumors of the heart. They can be fatal with a thromboembolic presentation. Myocardial infarction is one of these unusual thromboembolic presentations. We report a patient who presented with cardiac arrest due to ventricular fibrillation related to myocardial infarction. After successful resuscitation, coronary angiography and transthoracic echocardiography were performed. A left atrial mass was observed and interpreted as a possible cause of coronary embolism leading to myocardial infarction. After surgical excision, the pathological examination confirmed myxoma, which was the essential cause of the tendency to arterial embolism.     

Three eyelid localized cutaneous anthrax cases

Anthrax is primarily seen in the developing countries, but it can be a worldwide medical concern due to bioterrorism threats. Palpebral anthrax is a rare form of cutaneous anthrax. Untreated cutaneous anthrax can be lethal. Patients with palpebral anthrax can develop complications including cicatrisation and ectropion. Thus, anthrax should be considered in differential diagnosis for patients presenting with preseptal cellulitis in high-risk regions. Herein, we report three anthrax cases (with different age) involving eyelids that were cured without any complications due to early diagnosis and treatment.     

Surgical rehabilitation following ocular chemical injury

Purpose: The purpose of this study is to evaluate the management of limbal stem cell deficiency (LSCD) secondary to chemical ocular burns.

Materials and methods: The charts of 48 eyes of 40 patients with grade 2 or higher chemical injury were evaluated retrospectively. Subjects with follow-up longer than 1 year were included. Medical treatment, surgical correction of abnormalities of ocular adnexial structures, limbal stem cell transplantation from patient’s fellow eye, from living relatives or from cadaveric donor, amniotic membrane transplantation, conjunctival epitheliectomy, chelation with ethylenediaminetetraacetic acid and penetrating keratoplasty were the treatment modalities. Outcome measures were ocular surface stability and corrected distance visual acuity (CDVA). Failure was defined as the appearance of persistent epithelial defect (nonhealing epithelial defect for more than 2 weeks) with progressive corneal conjunctivalization/vascularization and thinning, and also progression of conjunctivalization to the central 6?mm of the cornea in eyes with subsequent keratoplasty.

Results: The mean age of 31 male and 9 female patients were 32.32?±?12.6 years. LSCD was bilateral in 8 cases. The mean follow-up was 77.2?±?35.1 months. The presentations were in acute phase in 37.5%, in subacute phase in 32.5% and in chronic phase in 30% of the patients. Only 13 of 48 (27.1%) eyes obtained sufficient ocular surface stability through medical treatment; however, only 5 of these eyes achieved CDVA of less than 0.7 logMAR. Limbal stem cell transplantation was performed in 26 eyes as conjunctival limbal autograft, living-related conjunctival limbal allograft and keratolimbal allograft or as a combination of these transplantations. At the last visit, 30 eyes (62.5%) had an intact and stable ocular surface. Clear cornea was achieved in 11 (78.6%) of 14 eyes with grade 2 injury, in 9 (60%) of 15 eyes with grade 3 injury, in 5 (50%) of 10 eyes with grade 4 injury, in 1 (16.6%) of 6 eyes with grade 5 injury and in 1 (33.3%) of 3 eyes with grade 6 injury. The CDVA that was 1.66?±?0.99 logMAR initially improved to 0.87?±?0.85 logMAR at the last visit (p?Conclusion: While patients with low-grade chemical injury seem to benefit quite well from the medical treatment, amniotic membrane transplantation, limbal graft transplantation and subsequent keratoplasty; patients with severe injuries seem to be more prone to failure after all of the available treatment modalities.     

A hematopoietic growth factor, thrombopoietin, has a proapoptotic role in the brain

Central nervous and hematopoietic systems share developmental features. We report that thrombopoietin (TPO), a stimulator of platelet formation, acts in the brain as a counterpart of erythropoietin (EPO), a hematopoietic growth factor with neuroprotective properties. TPO is most prominent in postnatal brain, whereas EPO is abundant in embryonic brain and decreases postnatally. Upon hypoxia, EPO and its receptor are rapidly reexpressed, whereas neuronal TPO and its receptor are down-regulated. Unexpectedly, TPO is strongly proapoptotic in the brain, causing death of newly generated neurons through the Ras-extracellular signal-regulated kinase 1/2 pathway. This effect is not only inhibited by EPO but also by neurotrophins. We suggest that the proapoptotic function of TPO helps to select for neurons that have acquired target-derived neurotrophic support.     

The evaluation of excessive daytime sleepiness in taxi drivers

Excessive daytime sleepiness (EDS) is a common but underrecognized and preventable cause of traffic accidents. It creates a problem of particular importance for professional drivers. We performed the Epworth Sleepiness Scale (ESS) and questionnaire related to their history of traffic accidents to 118 professional taxi drivers to determine the EDS and its effects on driving performance in taxi drivers. There were 58 (49.2%) subjects with loud snoring, 8 (5.9%) subjects with cardinal symptoms due to obstructive sleep apnea syndrome (OSAS) and 28 (23.7%) subjects with ESS > or =10 in the group of taxi drivers. Eighty (67.8%) drivers had been involved in a traffic accident. We found a significant relation between the number of traffic accident and EDS, witnessed apnea, cardinal symptom related to OSAS but not with snoring. The present data that sleepiness is a common symptom in taxi drivers and may be related to traffic accident.