Expression of Nestin by Neural Cells in the Adult Rat and Human Brain

Neurons and glial cells in the developing brain arise from neural progenitor cells (NPCs). Nestin, an intermediate filament protein, is thought to be expressed exclusively by NPCs in the normal brain, and is replaced by the expression of proteins specific for neurons or glia in differentiated cells. Nestin expressing NPCs are found in the adult brain in the subventricular zone (SVZ) of the lateral ventricle and the subgranular zone (SGZ) of the dentate gyrus. While significant attention has been paid to studying NPCs in the SVZ and SGZ in the adult brain, relatively little attention has been paid to determining whether nestin-expressing neural cells (NECs) exist outside of the SVZ and SGZ. We therefore stained sections immunocytochemically from the adult rat and human brain for NECs, observed four distinct classes of these cells, and present here the first comprehensive report on these cells. Class I cells are among the smallest neural cells in the brain and are widely distributed. Class II cells are located in the walls of the aqueduct and third ventricle. Class IV cells are found throughout the forebrain and typically reside immediately adjacent to a neuron. Class III cells are observed only in the basal forebrain and closely related areas such as the hippocampus and corpus striatum. Class III cells resemble neurons structurally and co-express markers associated exclusively with neurons. Cell proliferation experiments demonstrate that Class III cells are not recently born. Instead, these cells appear to be mature neurons in the adult brain that express nestin. Neurons that express nestin are not supposed to exist in the brain at any stage of development. That these unique neurons are found only in brain regions involved in higher order cognitive function suggests that they may be remodeling their cytoskeleton in supporting the neural plasticity required for these functions

In Vitro Dedifferentiation of Melanocytes from Adult Epidermis

In previous work we described a novel culture technique using a cholera toxin and PMA-free medium (Mel-mix) for obtaining pure melanocyte cultures from human adult epidermis. In Mel-mix medium the cultured melanocytes are bipolar, unpigmented and highly proliferative. Further characterization of the cultured melanocytes revealed the disappearance of c-Kit and TRP-1 and induction of nestin expression, indicating that melanocytes dedifferentiated in this in vitro culture. Cholera toxin and PMA were able to induce c-Kit and TRP-1 protein expressions in the cells, reversing dedifferentiation. TRP-1 mRNA expression was induced in dedifferentiated melanocytes by UV-B irradiated keratinocyte supernatants, however direct UV-B irradiation of the cells resulted in further decrease of TRP-1 mRNA expression. These dedifferentiated, easily accessible cultured melanocytes provide a good model for studying melanocyte differentiation and possibly transdifferentiation. Because melanocytes in Mel-mix medium can be cultured with human serum as the only supplement, this culture system is also suitable for autologous cell transplantation

Сопоставление рентгенологической и патоморфологической картины легких у пациентов с COVID-19

Aim. Compare radiological patterns of COVID-19 pneumonia with pulmonary histology in deceased patients.Materials and methods. The analysis of recent lifetime CT studies of deceased patients was performed with the identification of all existing and leading CT symptoms, including “ground glass”, “crazy paving”, consolidation, as well as the symptom complex (pattern) of organizing pneumonia. Based on the CT symptoms, we selected the target points for taking the specimens by 3-D reconstructions. At the autopsy the lungs were entirely fixed into the front and then marked on CT sections cut from 1 to 3 pieces that were placed in paraffin and processed according to the standard technique, stained with hematoxylin and eosin and fuchsin-facelina. The specimens were analyzed by identifying all available histology changes and selecting the leading one.Results. 45 targeted pieces of lung tissue were obtained from 14 deceased COVID-19 patients (7 men/ 7 women), with an average age of 77.1 ± 12.9 (49–90 years). In deceased patients with the presence of the "ground glass" symptom, in most cases (57.1%) revealed an increase in intra-alveolar cellularity, hyaline membranes, desquamation of the alveolar epithelium and infiltration of the interalveolar septum by lymphocytes, which corresponds to the exudative phase of diffuse alveolar damage (DAP). Mosaic histological changes with alternation of filled alveoli (intraalveolar edema, clusters of red blood cells, macrophages, lymphocytes) and air alveoli were detected from the areas of “crazy paving” zones. Several cases demonstrated interstitial edema and lymphoid infiltration of interalveolar partitions of different severity without their thickening. Areas of consolidation were histologically represented by extensive intraalveolar hemorrhages and / or typical zones of hemorrhagic infarcts in 45.5% of cases. Perilobular consolidation, subpleural cords, symptoms of “halo” and “reverse halo”, which we considered as part of the symptom complex of organizing pneumonia in 43% of cases, morphologically corresponded to organizing pneumonia (the proliferative phase of DAP), as well as to distelectases.Conclusion. Comparison of CT patters and post-mortem pulmonary histology in COVID-19 deceased patients demonstrated that CT symptoms and patterns correspond to certain morphological changes of different phases of DAP.Цель исследования: сопоставить рентгенологические паттерны COVID-19 с гистологическими изменениями у умерших.Материал и методы. Проведен анализ последних прижизненных КТ-исследований умерших пациентов с выделением всех имеющихся и ведущего КТ-симптомов, включая “матовое стекло”, “булыжная мостовая”, консолидация, а также симптомокомплекс (паттерн) организующейся пневмонии. На основании выделенных КТ-симптомов были выбраны прицельные точки взятия материала при помощи построения трехмерных реконструкций. На аутопсии фиксированные целиком легкие разрезались фронтально, далее из обозначенных на компьютерной томограмме участков вырезали от 1 до 3 кусочков, которые заливались в парафин и обрабатывались по общепринятой методике с последующей окраской срезов толщи- ной 3–5 мкм гематоксилином и эозином, пикрофуксин-фукселином. Анализ материала проводили путем выявления всех имеющихся патоморфологических изменений с выделением ведущего из них.Результаты. Были получены 45 прицельно взятых кусочков ткани легкого от 14 умерших (7 мужчин/ 7 женщин), средний возраст 77,1 ± 12,9 (49–90) года. У умерших пациентов с наличием симптома “матово- го стекла” при КТ в большинстве случаев (57,1%) были выявлены увеличение числа клеток в просветах альвеол (внутриальвеолярная клеточность), гиалиновые мембраны, десквамация альвеолярного эпителия и инфильтрация лимфоцитами межальвеолярных перегородок, что может соответствовать признакам экссудативной фазы диффузного альвеолярного повреждения (ДАП). Из участков, обозначенных как зоны “булыжной мостовой”, были выявлены мозаичные гистологические изменения с чередованием заполненных альвеол (внутриальвеолярный отек, скопления эритроцитов, макрофагов, лимфоцитов) и воздушных альвеол, местами при наличии интерстициального отека и лимфоидной инфильтрации межальвеолярных перегородок разной степени выраженности без их утолщения. Участки консолидации гистологически были представлены обширными внутриальвеолярными кровоизлияниями и/или типичными зонами геморрагических инфарктов в 45,5% случаев. Перилобулярная консолидация, субплевральные тяжи, симптомы “ободка” и “обратного ободка”, которые мы расценивали в рамках симптомокомплекса организующейся пневмонии, на компьютерной томограмме в 43% случаев морфологически соответствовали организующейся пневмонии (пролиферативная фаза ДАП), а также дистелектазам.Заключение. При попытке рентгенопатоморфологического сопоставления у пациентов с COVID-19 с поражением легких нами было показано, что различные симптомы и паттерны при КТ соответствуют определенным морфологическим изменениям в различные фазы ДАП

In Situ Dividing and Phagocytosing Retinal Microglia Express Nestin, Vimentin, and NG2 In Vivo

BACKGROUND: Following injury, microglia become activated with subsets expressing nestin as well as other neural markers. Moreover, cerebral microglia can give rise to neurons in vitro. In a previous study, we analysed the proliferation potential and nestin re-expression of retinal macroglial cells such as astrocytes and Müller cells after optic nerve (ON) lesion. However, we were unable to identify the majority of proliferative nestin(+) cells. Thus, the present study evaluates expression of nestin and other neural markers in quiescent and proliferating microglia in naïve retina and following ON transection in adult rats in vivo. METHODOLOGY/PRINCIPAL FINDINGS: For analysis of cell proliferation and cells fates, rats received BrdU injections. Microglia in retinal sections or isolated cells were characterized using immunofluorescence labeling with markers for microglia (e.g., Iba1, CD11b), cell proliferation, and neural cells (e.g., nestin, vimentin, NG2, GFAP, Doublecortin etc.). Cellular analyses were performed using confocal laser scanning microscopy. In the naïve adult rat retina, about 60% of resting ramified microglia expressed nestin. After ON transection, numbers of nestin(+) microglia peaked to a maximum at 7 days, primarily due to in situ cell proliferation of exclusively nestin(+) microglia. After 8 weeks, microglia numbers re-attained control levels, but 20% were still BrdU(+) and nestin(+), although no further local cell proliferation occurred. In addition, nestin(+) microglia co-expressed vimentin and NG2, but not GFAP or neuronal markers. Fourteen days after injury and following retrograde labeling of retinal ganglion cells (RGCs) with Fluorogold (FG), nestin(+)NG2(+) microglia were positive for the dye indicating an active involvement of a proliferating cell population in phagocytosing apoptotic retinal neurons. CONCLUSIONS/SIGNIFICANCE: The current study provides evidence that in adult rat retina, a specific resident population of microglia expresses proteins of immature neural cells that are involved in injury-induced cell proliferation and phagocytosis while transdifferentiation was not observed

Ethnic comparison in takotsubo syndrome: novel insights from the International Takotsubo Registry

Background Ethnic disparities have been reported in cardiovascular disease. However, ethnic disparities in takotsubo syndrome (TTS) remain elusive. This study assessed differences in clinical characteristics between Japanese and European TTS patients and determined the impact of ethnicity on in-hospital outcomes.Methods TTS patients in Japan were enrolled from 10 hospitals and TTS patients in Europe were enrolled from 32 hospitals participating in the International Takotsubo Registry. Clinical characteristics and in-hospital outcomes were compared between Japanese and European patients.Results A total of 503 Japanese and 1670 European patients were included. Japanese patients were older (72.6 +/- 11.4 years vs. 68.0 +/- 12.0 years; p < 0.001) and more likely to be male (18.5 vs. 8.4%; p< 0.001) than European TTS patients. Physical triggering factors were more common (45.5 vs. 32.0%; p < 0.001), and emotional triggers less common (17.5 vs. 31.5%; p < 0.001), in Japanese patients than in European patients. Japanese patients were more likely to experience cardiogenic shock during the acute phase (15.5 vs. 9.0%; p < 0.001) and had a higher in-hospital mortality (8.2 vs. 3.2%; p< 0.001). However, ethnicity itself did not appear to have an impact on in-hospital mortality. Machine learning approach revealed that the presence of physical stressors was the most important prognostic factor in both Japanese and European TTS patients.Conclusion Differences in clinical characteristics and in-hospital outcomes between Japanese and European TTS patients exist. Ethnicity does not impact the outcome in TTS patients. The worse in-hospital outcome in Japanese patients, is mainly driven by the higher prevalence of physical triggers.Cardiolog

Prognostic impact of acute pulmonary triggers in patients with takotsubo syndrome: new insights from the International Takotsubo Registry

Aims Acute pulmonary disorders are known physical triggers of takotsubo syndrome (TTS). This study aimed to investigate prevalence of acute pulmonary triggers in patients with TTS and their impact on outcomes.Methods and results Patients with TTS were enrolled from the International Takotsubo Registry and screened for triggering factors and comorbidities. Patients were categorized into three groups (acute pulmonary trigger, chronic lung disease, and no lung disease) to compare clinical characteristics and outcomes.Of the 1670 included patients with TTS, 123 (7%) were identified with an acute pulmonary trigger, and 194 (12%) had a known history of chronic lung disease. The incidence of cardiogenic shock was highest in patients with an acute pulmonary trigger compared with those with chronic lung disease or without lung disease (17% vs. 10% vs. 9%, P = 0.017). In-hospital mortality was also higher in patients with an acute pulmonary trigger than in the other two groups, although not significantly (5.7% vs. 1.5% vs. 4.2%, P = 0.13). Survival analysis demonstrated that patients with an acute pulmonary trigger had the worst long-term outcome (P = 0.002). The presence of an acute pulmonary trigger was independently associated with worse long-term mortality (hazard ratio 2.12, 95% confidence interval 1.33-3.38; P = 0.002).Conclusions The present study demonstrates that TTS is related to acute pulmonary triggers in 7% of all TTS patients, which accounts for 21% of patients with physical triggers. The presence of acute pulmonary trigger is associated with a severe in-hospital course and a worse long-term outcome.Cardiolog

Impact of atrial fibrillation on outcome in Takotsubo syndrome: data from the international Takotsubo registry

Background Atrial fibrillation (AF) is a major risk factor for mortality. The prevalence, clinical correlates, and prognostic impact of AF in Takotsubo syndrome (TTS) have not yet been investigated in a large patient cohort. This study aimed to investigate the prevalence, clinical correlates, and prognostic impact of AF in patients with TTS. Methods and Results Patients with TTS were enrolled from the International Takotsubo Registry, which is a multinational network with 26 participating centers in Europe and the United States. Patients were dichotomized according to the presence or absence of AF at the time of admission. Of 1584 patients with TTS, 112 (7.1%) had AF. The mean age was higher (P<0.001), and there were fewer women (P=0.046) in the AF than in the non-AF group. Left ventricular ejection fraction was significantly lower (P=0.001), and cardiogenic shock was more often observed (P<0.001) in the AF group. Both in-hospital (P<0.001) and long-term mortality (P<0.001) were higher in the AF group. Multivariable Cox regression analysis revealed that AF was independently associated with higher long-term mortality (hazard ratio, 2.31; 95% CI, 1.50-3.55; P<0.001). Among patients with AF on admission, 42% had no known history of AF before the acute TTS event, and such patients had comparable in-hospital and long-term outcomes compared with those with a history of AF. Conclusions In patients presenting with TTS, AF on admission is significantly associated with increased in-hospital and long-term mortality rates. Whether antiarrhythmics and/or cardioversion are beneficial in TTS with AF should thus be tested in a future trial. Registration URL: ; Unique identifier: NCT01947621.Cardiolog

HOW NEW APPROACHES TO THE TREATMENT OF PULMONARY EMBOLISM AFFECT THE OUTCOME OF THE DISEASE?

Pulmonary embolism (PE) is the key potentially reversible cause of in-hospital mortality. To help the practitioner, leading experts in different countries are developing and updating guidelines which analyze and generalize approaches to the treatment of PE. Recently, among the factors leading to positive dynamics in outcomes of patients with PE (according to the RIETE registry),the researchers have considered improvement of diagnostic techniques as well as technical improvements in tomographic scanners. Another reason for improved outcomes of treated patients with deep vein thrombosis and pulmonary embolism is optimization of anticoagulation therapy. The emergence of “new” oral anticoagulants (NOAC: rivaroxaban, dabigatran, apixaban) marked the beginning of a qualitatively new approach to the treatment of PE characterized by convenience of treatment without the need for regular monitoring of blood coagulation parameters. In addition to the emergence of new convenient and effective drugs, the approach to diagnosis and treatment of patients also changed, as reflected in the updated guidelines for the management of patients with venous thromboembolic complications (ESC 2014, ACCP 2016)