Replicative senescence of human dermal fibroblasts affects structural and functional aspects of the Golgi apparatus

It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.     

Neural plasticity and adult neurogenesis: the deep biology perspective

The recognition that neurogenesis does not stop with adolescence has spun off research towards the reduction of brain disorders by enhancing brain regeneration. Adult neurogenesis is one of the tougher problems of developmental biology as it requires the generation of complex intracellular and pericellular anatomies, amidst the danger of neuroinflammation. We here review how a multitude of regulatory pathways optimized for early neurogenesis has to be revamped into a new choreography of time dependencies. Distinct pathways need to be regulated, ranging from neural growth factor induced differentiation to mitochondrial bioenergetics, reactive oxygen metabolism, and apoptosis. Requiring much Gibbs energy consumption, brain depends on aerobic energy metabolism, hence on mitochondrial activity. Mitochondrial fission and fusion, movement and perhaps even mitoptosis, thereby come into play. All these network processes are interlinked and involve a plethora of molecules. We recommend a deep thinking approach to adult neurobiology.     

Role of the pelvic floor in bladder neck opening and closure I: Muscle forces

The aim of the study was to identify the striated muscle forces hypothesized to assist bladder neck opening and closure in females. Cadaveric dissection was used to identify the levator plate (LP), the anterior portion of pubococcygeus muscle (PCM), the longitudinal muscle of the anus (LMA), and their relation to the bladder, vagina and rectum. X-ray video recordings were made during coughing, straining, squeezing and micturition in a group of 20 incontinent patients and 4 controls, along with surface EMG, urethral pressure and digital palpation studies. During effort, urethral closure appeared to be activated by a forward muscle force corresponding to PCM, and bladder neck closure by backward muscle forces corresponding to LP and LMA. During micturition the PCM force appeared to relax, allowing LP and LMA to pull open the outflow tract. The data appear to support the hypothesis of specific directional muscle forces stretching the vagina to assist bladder neck opening and closure.     

Thin-layer chromatography systems for the identification of Mycobacterium tuberculosis, M. bovis BCG, M. kansasii, M. gastri and M. marinum.

Knowledge of mycobacterial glycolipid antigens and the study of their specificity have resulted in their utilization as species markers. We describe a thin-layer chromatography method which could serve as a useful adjunct for the identification of Mycobacterium tuberculosis, M. bovis BCG, M. kansasii, M. gastri and M. marinum.     

Soluble factors levels in the initial staging of high-grade non-Hodgkin's lymphomas.

Plasma levels of several soluble factors were assayed in 31 untreated patients with high-grade non-Hodgkin's lymphomas (NHL). The results showed statistically significant higher average levels of interleukin-2 (IL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-2 receptor (IL-2r) and transferrin receptor (TF-r) in NHL patients compared to controls (p = 0.045, p = 0.047, p = 0.020, p = 0.026 and p = 0.033 respectively). IL-2, IL-2r and TF-r levels were found more elevated in Stages III/IV than in Stages I/II (p = 0.031, p = 0.016 and p = 0.048 respectively), whereas IL-6 concentrations were higher in patients presenting B symptoms (p = 0.011). Significant correlations were found between the erythrocyte sedimentation rate (ESR) and IL-6 (r = 0.681), and between beta 2 microglobulin (B2-m) and IL-2r (r = 0.622).