The clinical significance of rigors in febrile children

The objective of the study was to evaluate the significance of rigor as a predictor of bacterial infection in hospitalized febrile infants and children. One hundred febrile children with rigor were studied and compared to 334 febrile matched controls without rigor. All underwent clinical evaluation and appropriate laboratory investigations. The patients were then divided into “bacterial” and “non bacterial” infection groups, as defined in the text. It was demonstrated that 66% of the patients with rigor belonged to the bacterial infection group versus 50% in the non-rigor group (P< 0.005). There was a significantly greater yield of positive blood cultures in the patients with rigor (P < 0.04), especially those over the age of 1 year (P < 0.015). The only laboratory examination of potential value as a predictor of bacterial infection in children with rigor was the band count. An absolute band count of more than 1500/mm was significantly more frequent in the rigor group (P < 0.003), and the combination of a rigor and band count of more than 1500 increased the relative risk for a bacterial infection by a factor of 1.35. These data demonstrate that rigor in hospitalized febrile infants or children significantly increase the likelihood of bacterial infection. Conclusion Although the absence of rigors in febrile children does not exclude bacterial aetiology, their presence significantly increases the probability of an infection requiring appropriate workup and a readier institution of antibiotic therapy. Received: 7 June 1996 / Accepted: 15 November 1996     

Effects of two anaesthetic regimes, MS-222 and eugenol, on plasma biochemical profile in Barbus sharpeyi

For choosing an anaesthetic agent for a particular purpose, the different properties has been notified such as the convenience for use, safety for the fish, humans and the environment, effectiveness, physiological disturbances and its cost. Invariably, in any study with clove oil, it has been regarded as an effective and acceptable alternative to other anaesthetics. The aim of the present study was to investigate effects of two anaesthetic regimes, MS-222 and eugenol, on plasma biochemical parameters in Barbus sharpeyi. B. sharpeyi fingerlings (mean weight, 5?g?±?1; mean length, 6?cm?±?1) were exposed to MS-222 (100?ppm) and eugenol (40?ppm) for induction of anaesthesia. Blood samples were taken to verify the effects of these anaesthetics on plasma biochemical parameters may use as an indicator of stress at time 0 (designated for each tank at the time of exposure to anaesthetic agent), 0.5, 1, 2 and 24?h after exposure by caudal severance. Plasma biochemical parameters concentrations were not significantly affected in B. sharpeyi (p?<?0.05). These results were expected because the trials were conducted in short-term exposures. Ion balance appears to be altered only in long-term stressing condition. Based on the results of this study, eugenol appears to be a safe anesthetic for use in B. sharpeyi.     

Same molecule but different expression: aging and sepsis trigger NLRP3 inflammasome activation,a target of melatonin

The connection between the innate immune system, clock genes, and mitochondrial bioenergetics was analyzed during aging and sepsis in mouse heart. Our results suggest that the sole NF‐κB activation does not explain the inflammatory process underlying aging; the former also triggers the NLRP3 inflammasome that enhances caspase‐1‐dependent maturation of IL‐1β. In this way, aged mice enter into a vicious cycle as IL‐1β further activates the NF‐κB/NLRP3 inflammasome link. The origin of NF‐κB activation was related to the age‐dependent Bmal1/Clock/RORα/Rev‐Erbα loop disruption, which lowers NAD⁺ levels, reducing the SIRT1 deacetylase ability to inactivate NF‐κB. Consequently, NF‐κB binding to DNA increases, raising the formation of proinflammatory mediators and inducing mitochondrial impairment. The cycle is then closed with the subsequent NLRP3 inflammasome activation. This paired contribution of the innate immune pathways serves as a catalyst to magnify the response to sepsis in aged compared with young mice. Melatonin administration blunted the septic response, reducing inflammation and oxidative stress, and enhancing mitochondrial function at the levels of nonseptic aged mice, but it did not counteract the age‐related inflammation. Together, our results suggest that, although with different strengths, chronoinflammaging constitutes the biochemical substrate of aging and sepsis, and identifies the NLRP3 inflammasome as a new molecular target for melatonin, providing a rationale for its use in NLRP3‐dependent diseases.     

Melatonin enhances neural stem cell differentiation and engraftment by increasing mitochondrial function

Neural stem cells (NSCs) are regarded as a promising therapeutic approach to protecting and restoring damaged neurons in neurodegenerative diseases (NDs) such as Parkinson's disease and Alzheimer's disease (PD and AD, respectively). However, new research suggests that NSC differentiation is required to make this strategy effective. Several studies have demonstrated that melatonin increases mature neuronal markers, which reflects NSC differentiation into neurons. Nevertheless, the possible involvement of mitochondria in the effects of melatonin during NSC differentiation has not yet been fully established. We therefore tested the impact of melatonin on NSC proliferation and differentiation in an attempt to determine whether these actions depend on modulating mitochondrial activity. We measured proliferation and differentiation markers, mitochondrial structural and functional parameters as well as oxidative stress indicators and also evaluated cell transplant engraftment. This enabled us to show that melatonin (25 μM) induces NSC differentiation into oligodendrocytes and neurons. These effects depend on increased mitochondrial mass/DNA/complexes, mitochondrial respiration, and membrane potential as well as ATP synthesis in NSCs. It is also interesting to note that melatonin prevented oxidative stress caused by high levels of mitochondrial activity. Finally, we found that melatonin enriches NSC engraftment in the ND mouse model following transplantation. We concluded that a combined therapy involving transplantation of NSCs pretreated with pharmacological doses of melatonin could efficiently restore neuronal cell populations in PD and AD mouse models depending on mitochondrial activity promotion.     

Assessment of Ventricular Functions by Tissue Doppler Echocardiography in Children with Asthma

Patients with asthma develop pulmonary hypertension due to recurrent hypoxia and chronic inflammation, leading to right heart enlargement with ventricular hypertrophy. Patients with severe asthma can experience cor pulmonale later in life, but little is known about ventricular function during the early stages of the disease. This study aimed to investigate ventricular functions in asymptomatic children with asthma as detected by conventional echocardiography and tissue Doppler echocardiography (TDE). Fifty-one pediatric patients (mean age 10.4 ± 2.2 years) with asthma and 46 age- and sex-matched healthy children (mean age 10.9 ± 2.4 years) were studied. All subjects were examined by conventional echocardiography and TDE, and they had pulmonary function tests on spirometry. The right-ventricular (RV) wall was statistically (p = 0.01) thicker among asthmatic patients (4.7 ± 1.5 mm) compared with healthy children (3.6 ± 0.4 mm). However, conventional pulsed-Doppler indices of both ventricles did not differ significantly between asthmatic patients and healthy children (p > 0.05). The results of TDE examining RV diastolic function showed that annular peak velocity during early diastole (E′), annular peak velocity during late diastole (A′) (16.4 ± 1.8 and 5.1 ± 1.4 cm/s, respectively), E′/A′ ratio (3.2 ± 0.7), isovolumetric relaxation time (67.7 ± 10.2 ms) and myocardial performance index (48.1 % ± 7.0 %) of the lateral tricuspid annulus among asthmatic patients differed significantly (p = 0.01) from those of healthy children (13.2 ± 2.3, 8.2 ± 2.0 cm/s, 1.6 ± 0.5, 46.2 ± 8.7 ms, and 42.0 % ± 5.7 %, respectively). Only peak expiratory flow (PEF) rate from the pulmonary function tests was negatively correlated with the E′/A′ ratio of the tricuspid annulus (r = ?0.38, p = 0.01). This study showed that although the findings of clinical and conventional echocardiography were apparently normal in children with asthma, TDE showed subclinical dysfunction of the right ventricle, which is negatively correlated with PEF. These findings signify the diagnostic value of TDE in the early detection and monitoring of such deleterious effects among asthmatic patients.