[Co-exposure of carbon black and cadmium induces autophagy and inflammation in human bronchial epithelial cells via PERK pathway].

Objective: To investigate the effects of carbon black and cadmium (Cd) combined exposure on autophagy and inflammatory response mediated by protein kinase R-like endoplasmic reticulum kinase (PERK) pathway in human bronchial epithelial (16HBE) cells. Methods: In January 2022, human bronchial epithelial (16HBE) cells were resuscitated and cultured. Carbon black nanoparticles (CBNPs) were oxidized to adsorb Cd ions to construct "CBNPs-Cd" complexes. CCK-8 assay was used to detect the effects of different concentrations and time combinations of CBNPs and Cd on the viability of 16HBE cells. The subsequent dose groups were exposed to 2 µg/ml Cd, 100 µg/ml CBNPs, 100 µg/ml CBNPs+2 µg/ml Cd for 24 h. The number of autophagosomes and autolysosomes was detected by transmission electron microscopy. Western blotting was used to detect the protein expressions of PERK, eukaryotic initiation factor 2α (eIf2α), activating transcription factor 4 (ATF4), sequestosome 1 (SQSTM1/P62), and microtubule-associated protein 1 light chain 3 (LC3). After PERK gene was silenced by siRNA technology, the changes of autophagy marker proteins P62 and LC3 were detected, and the expressions of inflammatory factors interleukin-6 (IL6) and interleukin-8 (IL8) were detected by fluorescence quantitative PCR technique. One-way ANOVA analysis was used to compare three groups or more. LSD test was used for comparison between two groups. Factorial analysis was used for multivariate component analysis. Results: There was no significant change in cell viability of 16HBE after 24 h exposure to CBNPs and Cd alone or combined (P>0.05). Compared with the control group, the expressions of P62 and LC3 in 16HBE cells were significantly increased in the CBNPs and Cd alone/combined exposure group (P<0.05), and the number of autophagosomes and autophagolysosomes in the combined exposure group was increased compared with other groups. Compared with the control group, CBNPs and Cd alone exposure group had no significant effects on p-PERK/PERK and p-eIf2α/eIf2α protein expression (P>0.05). However, the protein expressions of p-PERK/PERK and p-eIf2α/eIf2α and ATF4 were all increased in the combined exposure group (P<0.05), and the levels of IL6 and IL8 in 16HBE cells in the combined exposure group of CBNPs and Cd were significantly higher than those in the control group (P<0.05). The levels of LC3 protein, IL6 and IL8 were decreased in the CBNPs-Cd combined exposure group after knockdown of PERK gene (P<0.05). The results of factorial analysis showed that exposure to CBNPs and Cd had significant effects on the expression of P62, LC3 and IL6 (P<0.05), but the interaction between the two chemicals had no statistical significance (P>0.05) . Conclusion: CBNPs-Cd combined exposure may inhibit autophagy and increase inflammation in human bronchial epithelial cells through activation of PERK-eIf2α-ATF4 pathway.

Surgical treatment of solid brain stem tumors in adults: a report of 22 cases.

BACKGROUND: Brain stem tumors in adults are infrequent. Most reports of surgical treatment for these tumors involve partial tumor removal in highly selected patients. A more aggressive approach for removing tumors, especially solid and intrinsic ones, has been controversial. METHODS: Twenty-two adult patients with brain stem tumors were surgically treated. Surgical techniques, potential risks, and selection of appropriate treatment were evaluated. RESULTS: Tumors were totally or subtotally removed in 20 patients and only partially removed in two patients. Serious complications such as respiratory disturbances and circulatory dysfunction occurred in 10 patients. Eight patients with these complications recovered after appropriate treatments. Upon discharge, most signs and symptoms improved in 17 patients. CONCLUSION: Most brain stem tumors, except for malignant gliomas and small ventral tumors, are amenable to an aggressive surgical approach. Exophytic medullary tumors that present dorsally comprise the most benign subgroup of brain stem tumors. Total removal can enhance survival, improve the patient's quality of life, and offer a favorable long-term prognosis. Appropriate management of postoperative complications is essential for good results.

Aggressive surgery for intramedullary tumor of cervical spinal cord.

BACKGROUND: Intramedullary tumors of the cervical spinal cord are common and many believe they are amenable to an aggressive approach. However, surgical removal of intramedullary tumors of the cervical spinal cord is still controversial because of the great risk of respiratory dysfunction or quadriplegia or both upon resection of the tumor. METHODS: We present a consecutive series of 58 patients who underwent surgical treatment for intramedullary tumors of the cervical spinal cord. Surgical results are analyzed to refine our indications for surgery and its timing. The roles of preoperative radiotherapy and posttherapeutic cord appearance and function are discussed. RESULTS: Tumors were totally resected in 50 (86.2%), subtotally in seven and partially in one patient. Forty-five (77.6%) patients had improved neurologic status postoperatively. Intramedullary tumors in the cervical area have better results from surgery than intramedullary tumors in other levels of the spine. Patients with moderate neurologic deficits can recover remarkably well after total tumor removal. Laser surgery is especially helpful for lipoma. Preoperative radiotherapy should be avoided because it is associated with difficult surgery and poor clinical outcome. The thin spinal cord can function surprisingly well. CONCLUSIONS: We conclude that intramedullary tumors of the cervical spinal cord are amenable to total surgical removal. Surgery is suitable when a patient presents with a moderate neurologic deficit. Proficient surgical technique for total tumor resection is necessary for good results. Preoperative radiotherapy contributes to difficult surgery and poor prognosis, and is not recommended.

Magnetic resonance imaging and microsurgical treatment of intramedullary hemangioblastoma of the spinal cord.

Thirteen cases of intramedullary hemangioblastoma of the spinal cord are reported. The tumors were diagnosed with radiological studies, especially magnetic resonance imaging. Microsurgery was used to achieve gross total removal of the tumors in all cases. Signs and symptoms improved in 84.6% of the patients after surgery. The authors describe the diagnosis and microsurgical techniques for the excision of intramedullary hemangioblastoma of the spinal cord. This disease should be differentiated from hydromyelia, intramedullary ependymoma, and vascular malformation of the spinal cord. Total removal of the tumor is recommended.