Adverse event of Sinovac Coronavirus vaccine: Deafness.

COVID-19 has spread worldwide and is one of the most threatening infectious diseases in the world. Vaccination is known as an effective method to protect susceptible populations against such diseases. The Coronavirus vaccine developed by Sinovac has been shown to have a high protective effect, but it also has potential adverse events. For example, our department saw two patients with reported cases of deafness that occurred after inoculation with the Sinovac Coronavirus vaccine. While deafness is only a rare adverse event from the Coronavirus vaccine, whether other vaccination centers, hospitals, and centers for disease control (CDCs) have encountered similar cases still needs to be investigated, reported, and analyzed.

Use of Solid Lipid Nanoparticles for the Treatment of Acute Acoustic Stress-Induced Cochlea Damage.

To study the effects of drug delivery using solid lipid nanoparticles in the treatment of acute noise exposure-induced cochlea damage. The solid lipid nanoparticles (SLNs) were used as carriers to effectively encapsulate the drug clozapine, improve drug stability in the carrier system, and increase drug bioavailability in vivo. Solid lipid nanoparticles carrying clozapine were produced by ultrasonic technology. The clozapine solution or sulphate SLN was administered though intratympanic or intravenous injection on the first day of noise exposure Guinea pigs were exposed to 110 dB sound pressure level (SPL) noise (2 h per day with center frequencies of 0.25-4.0 kHz for 4 days). After noise exposure, the guinea pigs were subjected to auditory brainstem response (ABR) threshold measurements. Reactive oxygen species (ROS) levels were detected in the cochlea by electron spin resonance (ESR), and outer hair cell counts (OHCs) were obtained using silver nitrate (AgNO3). SLN particles carrying clozapine exhibited protective effects on the cochlea. The threshold shift and ROS production in treated animals, especially in animals treated with clozapine SLN through intraperitoneal injection, were significantly lower than those in untreated animals.

Cochlear Transfection Gene Guinea Pigs Mediates Atoh1-EGFP Based Hyaluronic Acid Modified Polyethyleneimine Nanoparticles.

To modify polyethyleneimine (PEI) nanoparticles using hyaluronic acid (HA) to prepare a novel nonviral vector and use it to coat Atoh1-EGFP plasmid to detect its translocation in living guinea pig cochlea dyeing efficiency. Atoh1-EGFP plasmid was extracted and characterized using a Zetasizer particle size analyzer. HA/PEI/DNA complexion was characterized and introduced into the round window membrane. EGFP green fluorescence carried in the Atoh1 plasmid was observed by confocal microscopy. The transfection results were verified by Western blot and reverse transcription polymerase chain reaction (RT-PCR) from the perspective of protein and nucleic acid to verify its expression results. In this study, HA-modified PEI nanoparticles are negatively-charged nanoscale gene carrier complexes. After the Atoh1-EGFP plasmid was introduced into the cochlea, the results of confocal microscopy showed that the inner and outer hair cells of the basement membrane could be detected in green fluorescent protein. The transfection efficiency of basement membrane is as high as 81.7±4.71%, while the transversion is 33.8±9.02%. Western Blot and RT-PCR also confirmed that the Atoh1 gene can be successfully transfected on the basement membrane. The gene transfection of cochlea may be achieved by HA-modified PEI nanoparticle gene vector with no obvious toxicity to basement membrane cells. It is also an ideal inner-end gene transfection vector owing to its simple synthesis method and low cost.

[Clinical application of the combined presigmoid supra-infratentorial approach].

OBJECTIVE: To explore the surgical approach to the lesions of the cerebellopontine angle and the petroclival region. METHOD: Nine cases of the cerebellopontine angle or petroclival large tumors and one case of the posterior cerebral thrombotic aneurysm were treated by the combined presigmoid supra-infratentorial approach. The tumors including 3 cases of schwannomas and 6 cases of meningiomas spaned supra-infratentorium in our study. RESULT: Complete tumor removal were achieved in 6 cases, and subtotal tumor removal in 4 cases. After the operation, Cerebrospinal fluid leakage followed intracranial infection occurred in 1 case which losing follow-up. Headache and dizziness relieved in the other 9 cases. One case improved and 3 cases with no improvement after surgery among the 4 preoperative facial paralysis patients. Three cases with cerebellar symptoms were much relieved, but most deficits involving other cranial nerves preoperation did not recover. According to Samii's prognosis standard, 7 cases with good results and 1 case with common and 1 case with bad had been achieved. The hearing level had no influence in 5 cases, declined 20 dB HL in 2 cases, 30 dB HL in 1 case and 60 dB HL, in I case. CONCLUSION: The combined presigmoid supra-infratentorial approach is a direct route to the petroclival region and the cerebellopontine angle, provides a wide surgical field with less cerebellar or brain retraction, facilitates the removal of lesions and preserves the cranial nerves functions.

[Combined frontal-preauricular-cervical approach for resection of huge transcranial lateral skull base tumors].

OBJECTIVE: To search into the appropriate approach for surgical treatment of the huge lateral skull base tumors. METHODS: The combined frontal-preauricular-cervical approach was used in two cases with huge transcranial lateral skull base tumors occupying the parapharngeal space, infratemporal fossa and middle cranial fossa. To acquire a wide surgical exposure, the flaps of orbital-zygomatic bone and the skull bone were removed, and then the mandibula was dislocated inferiorly. RESULTS: The tumors in the two cases were resected completely. The postoperative conditions of the patients were good. No cerebral spinal fluid leakage and other intracranial complications or facial morbidity were found. The occlusion was not interfered. CONCLUSION: The combined frontal-preauricular-cervical approach may provide a potential way for the surgical treatment of the large transcranial neoplasms occupying the parapharngeal space and infratemporal fossa and the middle cranial base.