Objective: To evaluate the efficacy and safety of plasma exchange (PE) in thymoma-associated myasthenia gravis (MG), thereby to provide theoretical support for its application in the treatment of thymoma-associated MG. Methods: A total of 133 patients with thymoma-associated MG admitted from January 2018 to September 2024 were retrospectively analyzed. Patients were matched using propensity score to reduce selection bias, yielding 22 matched pairs for both PE group (n=22) and non-PE group (n=22). Patient characteristics including gender, age of disease onset, course of disease, history of thymoma resection, clinical absolute scores [clinical absolute scores (CAS) and clinical relative scores (CRS)], and synchronized immunotherapy regimen of the two groups were analyzed. The CAS scores before and after treatment were compared between the two groups, and the CRS was used to assess the treatment efficiency. Safety of the two treatment regimens were also compared. Continuous variables were compared using the t-test or ANOVA, while categorical data were compared by the chi-square test. Results: A total of 133 patients were included and divided into two groups according to whether they underwent plasma exchange treatment: the PE group (n=22) and the non-PE group (n=111). To exclude bias caused by large difference in the number of cases between the two groups, we performed propensity score matching. After matching, the number of cases in both groups was 22. There was no significant difference in baseline clinical characteristics between the two groups (P>0.05), including gender, age of onset, duration of disease course, history of thymectomy and baseline CAS score before treatment. Compared to the non-PE group, patients in the PE group showed more significant improvement in CAS score (5.09±1.95 vs 3.59±1.50, P<0.05) and a higher CRS score (75.00% vs 50.00%, P<0.001). Compared to the non-PE group, PE group had significantly longer ICU stay, longer hospital stay and higher hospitalization cost (P<0.05). There was no statistically significant difference in adverse events between the two groups during treatment (P>0.05). During long-term follow-up, both the PE and non-PE groups showed relatively low 1-, 3-, and 5-year recurrence rate, with no significant difference between the two groups (P>0.05). Conclusion: This study indicates that plasma exchange has clear value in the treatment of patients with thymoma-associated myasthenia gravis. It can not only significantly improve patients' muscle strength to alleviate motor dysfunction and enhance quality of life, but also does not significantly increase the incidence of adverse reactions. Therefore, it can be regarded as one of the preferred treatment options that achieve a "balance between efficacy and safety" for such patients, and provides an important basis for optimizing treatment strategies, improving prognosis, and promoting the application of subsequent treatment regimens.

Portal vein thrombosis (PVT) is commonly seen in patients with liver cirrhosis. Patients with varices complicated by portal vein thrombosis are more likely to experience bleeding, with higher failure rate of hemostasis and rebleeding rate, and the patients receiving liver transplantation may have a poorer prognosis. There are various risk factors for portal vein thrombosis, such as severity of liver dysfunction, use of non-selective beta blockers, and portal vein blood flow velocity. This article reviews the risk factors for portal vein thrombosis in patients with liver cirrhosis, in order to further understand the mechanism and risk level of portal vein thrombosis.

Guinea pigs were exposed to either 110dB SPL white noise for 30min (ITS group )or 120 dB SPL for 150 nun (PTS group). At varying postexposure intervals, threshold shifts were assessed using auditory cortex evoked response to tone bursts and intracellular ultrastructural changes in the spiral organ of cochleae were exmained with a transmission electron microscope.. The threshold shifts induced by 110dB noise were reversible while those induced by 120dB noise were generally irreversible. In the TTS cochleae, damage was confined to the third row of OHCs where depolymerization of actin filaments within the stereocilia, slight celluar swelling and small vacuolization were found. The subnuclear area and nerve-endings were not involved. In the PTS cochleae, the inner hair cells (IHCs) and the first row of OHCs were affected. The abnormilities consisted of ruptures and holes in the cuticular plates, fusion of stereocilia, marked edema, tranclucence of subcuticular region, swelling of submembraneous cisterns and large vesiculation in the efferent nerve-endings blow OHCs. Based on the ultrastructural observations, structural bases in cochleae for TTS and PTS, sequence of pathological changes in hair cells as well as reversibility of specific pathologies were suggested.

Ultrastructural changes in the spiral organ of cochlea at various intervals after exposure to impulse noise were investigated. Guinea pigs were exposed to 10 impulses noise of 166 dB SPL peak level which had duration of 0.1 ms. Thirteen of the exposed animals were used to systematically measure threshold shift at regular intervals from 30 min to 30d post-exposure. The other fourteen animals who had been exposed to the same impulse noise were killed for transmission electron microscopy (TEM) examination at the same intervals, respectively. The recovery pattern of threshold shift showed a nonmonotonic type. There was a progressive deterioration of changes in the hair cells between 30 min and 8h after exposure. Intracellular degeneration reached a peak at 8h and marked edema and swelling leading to deformation of the outer hair cells (OHCs), fused stereocilia, large vesicles in cytoplasm and swollen submembraneous cisterns were found. After that time the extent of degeneration in the hair cells reduced. The time sequence of changes in the spiral organ of cochlea in the present study was associated with the recovery pattern of threshold shift.