The occurrence and development of tumors require the metabolic reprogramming of cancer cells, namely the alteration of flux in an autonomous manner via various metabolic pathways to meet increased bioenergetic and biosynthetic demands. Tumor cells consume large quantities of nutrients and produce related metabolites via their metabolism; this leads to the remodeling of the tumor microenvironment (TME) to better support tumor growth. During TME remodeling, the immune cell metabolism and antitumor immune activity are affected. This further leads to the escape of tumor cells from immune surveillance and therefore to abnormal proliferation. This review summarizes the regulatory functions associated with the abnormal biosynthesis and activity of metabolic signaling molecules during the process of tumor metabolic reprogramming. In addition, we provide a comprehensive description of the competition between immune cells and tumor cells for nutrients in the TME, as well as the metabolites required for tumor metabolism, the metabolic signaling pathways involved, and the functionality of the immune cells. Finally, we summarize current research targeted at the development of tumor immunotherapy. We aim to provide new concepts for future investigations of the mechanisms underlying the metabolic reprogramming of tumors and explore the association of these mechanisms with tumor immunity.
Background This study aimed to investigate the effectiveness of ultrasonography (US) and in vitro measurement (IVM) methods in localizing peripherally inserted central catheters (PICCs) in premature infants and analyze the relevant factors affecting the accuracy of IVM. Methodology The study employs a prospective before-and-after self-controlled clinical trial design. A total of 210 premature infants who underwent PICC catheterization were compared. We assessed the rate of catheter tip placement, consistency, and stability and analyzed the relevant factors. Results The study enrolled a total of 202 premature infants after eight infants dropped out. The one-time positioning rates of the PICC catheter tip using US and IVM were 100% and 73.8%, respectively. Concerning IVM, 53 (26.2%) patients did not reach the optimal position, with 24 (11.8%) patients having a shallow position and 29 (14.3%) having a deep position. The consistency of the two methods was 0.782 (p < 0.05). The degree of dispersion of US was 0.2 (0.0-0.4) cm, which was significantly smaller than IVM at 1.5 (0.0-1.8) cm. Gestational age less than 32 weeks (odds ratio (OR) = 6.64, 95% confidence interval (CI) = 1.43-30.81), weight less than 1,500 g (OR = 5.85, 95% CI = 2.11-16.20), body length less than 40 cm (OR = 15.36, 95% CI = 4.47-52.72), mechanical ventilation (OR = 5.13, 95% CI = 1.77-14.83), abdominal distension (OR = 78.18, 95% CI = 10.62-575.22), and bloating (OR = 8.81, 95% CI = 1.42-47.00) were risk factors that affected the accuracy of IVM. Conclusions Gestational age, weight, length, mechanical ventilation, abdominal distension, and swelling can lead to deviations with IVM. US can directly view the tip of the catheter, which is more accurate. Additionally, it is recommended to reduce the length of the catheter by 1.3 cm when using IVM to achieve the best-estimated placement length.
Abstract Background Bronchopulmonary dysplasia (BPD) is a complex lung pathological lesion secondary to multiple factors and one of the most common chronic lung diseases. It has a poor prognosis, especially in preterm infants. However, effective therapies for this disease are lacking. Stem-cell therapy is a promising way to improve lung injury and abnormal alveolarization, and the human umbilical cord (hUC) is a good source of mesenchymal stem cells (MSCs), which have demonstrated efficacy in other diseases. We hypothesized that intravenously administered allogeneic hUC-MSCs are safe and effective for severe BPD. Methods The MSC-BPD trial is a randomized, single-center, open-label, dose-escalation, phase-II trial designed to investigate the safety and efficacy of hUC-MSCs in children with severe BPD. In this study, 72 patients will be enrolled and randomly divided into two intervention groups and one control group. Patients in the intervention groups will receive a low dose of hUC-MSCs ( n = 24; 2.5 million cells/kg) or a high dose of hUC-MSCs ( n = 24; 5 million cells/kg) in combination with traditional supportive treatments for BPD. The patients in the control group ( n = 24) will be treated with traditional supportive treatments alone without hUC-MSCs. The primary outcome measures will be cumulative duration of oxygen therapy. Follow-up assessments will be performed at 1, 3, 6, 12, and 24 months post intervention, and the key outcome during follow-up will be changes on chest radiography. Statistical analyses will evaluate the efficacy of the hUC-MSC treatment. Discussion This will be the first randomized controlled trial to evaluate the safety and efficacy of intravenously administered hUC-MSCs in children with severe BPD. Its results should provide a new evidence-based therapy for severe BPD. Trial registration ClinicalTrials.gov, ID: NCT03601416 . Registered on 26 July 2018.
Both viral and bacterial infections can be associated with wheezing episodes in children; however, information regarding combined infections with both viral and bacterial pathogens in full term neonates is limited. We sought to investigate the effects of viral-bacterial codetection on pneumonia severity and recurrent wheezing. A retrospective cohort study was conducted on neonates admitted to our hospital with pneumonia from 2009 to 2015. Of 606 total cases, 341 were diagnosed with RSV only, and 265 were diagnosed with both RSV and a potential bacterial pathogen. The leading four species of bacteria codetected with RSV were Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus and Enterobacter cloacae. Neonates with RSV and a potential bacterial pathogen were significantly more likely to have worse symptoms, higher C-reactive protein values and more abnormal chest x-ray manifestations with Bonferroni correction for multiple comparisons (P < 0.01). On Cox regression analysis, an increased risk of recurrent wheezing was found for neonates positive for RSV-Staphylococcus aureus and RSV-Klebsiella pneumoniae. Our findings indicate that the combination of bacteria and RSV in the neonatal airway is associated with more serious clinical characteristics. The presence of RSV and Staphylococcus aureus or Klebsiella pneumoniae may provide predictive markers for wheeze.
Manganese is an indispensable trace element, however, it may be present at high concentrations in water and sediments of aquatic ecosystems due to natural and anthropogenic activities, and can interfere with physiological and biochemical mechanisms in fish. This study was conducted to determine the toxic effects associated with exposure to Mn 2+ (0, 0.5, 1, 2, and 4 mg/L) for 30 d, regarding liver damage and apoptosis in Yunlong grouper ( Epinephelus moara♀×E. lanceolatus♂ ). Expression of superoxide dismutase ( sod ) and catalase ( cat ) genes in the liver was significantly increased on days 10 and 20 following Mn 2+ exposure (4 mg/L), but was reduced on day 30. Similarly, expression of glutathione peroxidase ( gpx ) and glutathione reductase ( gr ) genes was elevated after 10 d of exposure to 2 and 4 mg/L Mn 2+ , but decreased after 20 and 30 d. After 30 d of exposure to high concentrations (2 and 4 mg/L) of Mn 2+ , liver tissue showed hepatic sinusoidal gap congestion, dilatation, cell vacuolation, and necrosis. In addition, the activities of alanine aminotransferase (ALT) and aspartate transaminase (AST) as well as 8-hydroxydeoxyguanosine (8-OHdG) levels were significantly increased after Mn 2+ exposure. Moreover, Mn 2+ exposure altered the expression pattern of some pivotal genes associated to apoptosis ( p53 , bax , bcl-2 , apaf-1 , caspase-9 , and caspase-3 ), which suggested that Mn 2+ exposure induces apoptosis through the mitochondrial pathway. The above results showed that excessive Mn 2+ induced apoptosis and liver damage in grouper through elicitation of oxidative stress. These insights help elucidate the mechanism by which Mn 2+ induces toxicity in marine fish, and provide a new perspective regarding the detrimental effects of heavy metals in fish.
Objective To investigate the effects of intrathecal (IT) ketamine on the synapsis remodeling in the spinal dorsal horn during devolopment of morphine tolerance in a rat model of neuropathic pain (NP). Methods Male SD rats weighing 200-250 g were used in this study. IT catheter was placed in the subarachnoid space according to Yaksh. Forty-eight SD rats in which IT catheter was successfully placed were randomly divided into 6groups (n=8 each): group sham operation (group S); group NP; group normal saline 20 μl IT(group NS);group morphine 20 μg IT (group M); group ketamine 50 μg IT (group K) and group morphine 20 μ g + ketamine 50 μg IT (group MK). NP was induced by compression of right L4,5 dorsal root ganglions with steel wire inserted through L4,5 intervertebral foramen in NP,M,K and MK groups. Normal saline or morphine and/or ketamine were injected IT once a day for consecutive 14 days. Paw withdrawal threshold (PWT) to mechanical stimulation and paw withdrawal latency (PWL) to a thermal nociceptive stimulus were measured on 0, 1, 3, 5, 7, 9, 11, 14 days during the consecutive 14 days of administration. The animals were sacrificed after the final IT administration. The lumbar segment of the spinal cord was removed for determination of the number of synapsis in the spinal dorsal horn by immuno-histochemistry in 4 animals in each group and observation of synaptic structure remodeling using electron microscope in another 4 animals in each group. Results Compared with group S, PWT was significantly decreased and PWL was shortened in the other 5 groups, and the number of synapsis was significantly increased and the synaptic structure was thickened in NP, NS, M and K groups (P < 0.05). Compared with group NP,PWT was significantly increased and PWL was prolonged in M, K and MK groups, and the number of synapsis was significantly decreased and the thickness of synaptic structure was significantly reduced in group MK ( P < 0.05).Compared with group M, PWT was significantly increased, PWL was prolonged, the number of synapsis was significantly decreased and the thickness of synaptic structure was significantly reduced in group MK ( P < 0.05). Conclusion IT ketamine can inhibit the synaptic remodeling in the spinal dorsal horn during development of morphine tolerance in a rat model of NP.
Key words:
Ketamine; Morphine; Drug tolerance; Injections, spinal; Neuralgia; Spinal cord; Synapses; Neuronal plasticity