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Activation of the immune system in heart failure (HF) has been recognized for over 20 years. Initially, experimental studies demonstrated a maladaptive role of the immune system. However, several phase III trials failed to show beneficial effects in HF with therapies directed against an immune activation. Preclinical studies today describe positive and negative effects of immune activation in HF. These different effects depend on timing and aetiology of HF. Therefore, herein we give a detailed review on immune mechanisms and their importance for the development of HF with a special focus on commonalities and differences between different forms of cardiomyopathies. The role of the immune system in ischaemic, hypertensive, diabetic, toxic, viral, genetic, peripartum, and autoimmune cardiomyopathy is discussed in depth. Overall, initial damage to the heart leads to disease specific activation of the immune system whereas in the chronic phase of HF overlapping mechanisms occur in different aetiologies.  相似文献   
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Purpose

To evaluate automatic peripapillary choroidal thickness (PPCT) measurements in a wide area around the optic disc and various established zones in primary open-angle glaucoma (POAG) patients and age- and sex-matched healthy controls using a new swept-source optical coherence tomography (SS-OCT) device.

Study design

Single center cross-sectional observational study.

Methods

A total of 135 POAG patients and 86 healthy subjects were consecutively enrolled. An optic disc 6.0 × 6.0 mm three-dimensional scan OD was obtained using the SS-OCT Triton. A 26 × 26 cube-grid centered in the optic disc was generated to automatically measure choroidal thickness. Seven choroidal zones were established (superior temporal, central, and nasal; inferior temporal, central, and nasal, and the optic nerve head) and compared between healthy controls and POAG patients.

Results

PPCT was significantly thinner in the central superior, nasal superior, and nasal inferior zones of the POAG subjects. Choroidal thickness in the central superior zone was 124.61 ± 54.95 µm in POAG group vs 156.17 ± 80.89 µm in healthy controls (p = 0.029); in the nasal superior zone, 133.84 ± 58.89 µm in the POAG group vs 168.34 ± 73.45 µm in healthy controls (p = 0.012); and in the nasal inferior zone, 113.45 ± 49.93 µm in the POAG group vs 137.47 ± 65.96 µm in healthy controls (p = 0.049).

Conclusion

Compared with healthy subjects, glaucoma patients present with peripapillary choroidal thinning, especially in the central superior, nasal superior, and nasal inferior zones. The new SS-OCT could be a useful tool to evaluate choroidal thinning, and it could be an additional support to facilitate glaucoma diagnosis.
  相似文献   
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Studying the cellular composition and morphological changes of cells lining the central canal during Xenopus laevis metamorphosis could contribute to understand postnatal development and spinal cord regeneration. Here we report the analysis of central canal cells at different stages during metamorphosis using immunofluorescence for protein markers expression, transmission and scanning electron microscopy and cell proliferation assays. The central canal was regionalized according to expression of glial markers, ultrastructure, and proliferation in dorsal, lateral, and ventral domains with differences between larvae and froglets. In regenerative larvae, all cell types were uniciliated, have a radial morphology, and elongated nuclei with lax chromatin, resembling radial glial cells. Important differences in cells of nonregenerative froglets were observed, although uniciliated cells were found, the most abundant cells had multicilia and revealed extensive changes in the maturation and differentiation state. The majority of dividing cells in larvae corresponded to uniciliated cells at dorsal and lateral domains in a cervical‐lumbar gradient, correlating with undifferentiated features. Neurons contacting the lumen of the central canal were detected in both stages and revealed extensive changes in the maturation and differentiation state. However, in froglets a very low proportion of cells incorporate 5‐ethynyl‐2′‐deoxyuridine (EdU), associated with the differentiated profile and with the increase of multiciliated cells. Our work showed progressive changes in the cell types lining the central canal of Xenopus laevis spinal cord which are correlated with the regenerative capacities.  相似文献   
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The Screen for Cognitive Impairment in Psychiatry is a simple, fast, and easy to administer scale that has been validated in clinical and community samples. The aim of this study was to propose a polytomous scoring system for the Screen for Cognitive Impairment in Psychiatry and to demonstrate its functioning, thus providing new and complementary information regarding the utility and precision of this screening tool. Three hundred seventy‐six Spanish patients diagnosed with schizophrenia spectrum disorder were evaluated. A polytomous scoring system was generated and analyzed by means of the partial credit model. Category assessment revealed optimal functioning after collapsing the 7‐category system to 1 with either 5 or 4 categories, depending on the item. The proposed polytomous scoring system shows good psychometric properties and an adequate fit to the partial credit model. These results provide further confirmation of the test's utility in clinical settings and of its suitability for detecting cognitive impairment.  相似文献   
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Congenital hypothyroidism is defined as thyroid hormone deficiency present at birth which is crucial for brain development. Recently, the cyclic alternating pattern, a rhythm present in electroencephalography recordings in non-Rapid eye movement sleep, has been related to brain development and cognition in different pediatric conditions. Therefore, we evaluated the cyclic alternating pattern rate in infants with congenital hypothyroidism, thyroxine supplementation, and healthy controls. The parameters of the cyclic alternating pattern were evaluated in 19 healthy infants (10 female, mean age 25.5?±?15.5?months) and 21 infants diagnosed with congenital hypothyroidism (19 female, mean age 24.3?±?19.0?months). We considered the transient electro-cortical activations (phase A of the cycle) in non-Rapid eye movement sleep and the subdivisions of the A phase in: A1, A2 and A3, based on their frequency content. All subjects were subjected to polysomnography recording in a standard laboratory setting. Sleep data were stored computer following the International 10–20 System. Data showed that congenital hypothyroidism infants exhibited higher frequency of central apnea, hypopnea, and arousals in comparison to controls. Particularly, central apnea index decreased with age in the control group but not in congenital hypothyroidism group. Regarding to cyclic alternating pattern measurements, congenital hypothyroidism infants exhibit a higher frequency in the percentage of A3 subtype (electroencephalographic desynchrony) and conversely a lower percentage of A1 subtype (electroencephalographic synchrony), than healthy infants. An important finding of this study is the positive correlation between A1 mean duration and age, which is bigger in control group than in congenital hypothyroidism group (time duration in control group (0.52?s/month) versus congenital hypothyroidism group (0.1?s/month). Infants with congenital hypothyroidism showed an increase of A3 subtype, of central apnea, and of arousals. The reduction of percentage and mean duration of A1 subtype could be a valuable indicator of sleep development in patients with congenital hypothyroidism and healthy infants.  相似文献   
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