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The remote direct memory access (RDMA) technology, which has been effectively utilized to enhance data transfer rates and reduce CPU utilization, has played a significant role in various domains such as cross-regional data center transfers, high-performance computing, and rapid data read/write operations. However, despite its emerging status, RDMA has been lacking in widely recognized security solutions. With the expansion of RDMA applications from dedicated network environments to general Ethernet networks, the need to address the security risks faced by these applications has become imperative. A set of protective measures were established to ensure security without compromising transmission efficiency. Furthermore, the unique underlying implementation and protocol design of RDMA technology have resulted in incompatibility with existing mature security solutions and have led to the confrontation with specific security risks. The development of RDMA attack and defense technologies and the provision of security guarantees for the forthcoming widespread application of RDMA technology were elucidated The principles of RDMA technology and its implementation were proposed, with examples drawn from the InfiniBand (IB) and the RDMA over converged Ethernet (RoCE) second edition protocols. The security risks faced by RDMA applications in relevant scenarios were investigated, and a summary of the research progress in the RDMA security field over recent years was provided. Effective security solutions addressing these risks were compiled and, after their defensive capabilities were proven, a comparison of their advantages and disadvantages was conducted through theoretical analysis and experimental data. Finally, improvement plans and prospects for technological optimization in the RDMA attack and defense field were proposed.

Objective To explore the circadian rhythm disorder characteristics of blood pressure in patients with acute ischemic stroke and its correlation with stroke prognosis. Methods A total of 346 subjects without a history of stroke were prospectively enrolled from the First People's Hospital of Lianyungang between October 2019 and January 2020, and they were 140 hospitalized patients with hypertensive first-onset ischemic stroke (hypertensive stroke group), 105 with simple hypertension (hypertensive group) and 101 cases with normal blood pressure (normal BP group). Ambulatory blood pressure monitoring was completed within 72 h after enrollment, then the patients were further divided into 4 groups based on the reduction of systolic BP from day to night: extreme-dipper, dipper, non-dipper, and reverse-dipper. The primary endpoint event (re-attack of stroke) and secondary endpoint events (non-fatal myocardial infarction, hospitalization due to heart failure, cardiogenic death or all-cause death) were followed up at 3, 6, 9 and 12 months after enrollment. Univariate and multivariate Cox regression analyses were adopted respectively to screen the potential risk factors of endpoint events, and to analyze the correlation between circadian rhythm of blood pressure and endpoint events. Finally, Kaplan-Meier survival curve was used to display the cumulative incidence of endpoint events with different circadian rhythms of blood pressure. Results The dipper BP accounted for 23.6% in the hypertensive stroke group, which was significantly lower than that in the hypertension group (43.8%, P=0.001) and normal BP group (68.3%, P < 0.001). The non-dipper and reverse-dipper BP in the hypertensive stroke group were 41.4% and 20.7%, respectively, greatly higher than those in the normal BP group (19.8%, P < 0.001; 6.9%, P=0.003), though there was no statistical significance in comparison with the hypertension group (31.4%, P=0.109; 13.3%, P=0.133). Multivariate Cox regression revealed that after adjustment for confounding factors, the reverse-dipper BP was independently correlated with both the primary endpoint events (HR=5.177, P=0.047) and the secondary endpoint events (HR=4.909, P=0.022). Moreover, the cumulative risks of both primary endpoint events (Log Rank P=0.020) and secondary endpoint events (Log Rank P=0.011) were notably increased in the reverse-dipper BP group than the dipper BP group. Conclusion Circadian rhythm disorder of blood pressure is prevalent among patients with acute ischemic stroke, and reverse-dipper BP rhythm is independently correlated with stroke onset and cardiovascular events.

Reversible splenial lesion syndrome (RESLES) is a single-stage non-specific syndrome with unclear pathogenesis. There has been no report on answer delay in patients with RESLES. We report a female patient who was admitted to our department for mixed aphasia accompanied by cognitive impairment. During the rapid improvement of aphasia, there was a clear phase of language output response delay accompanied by resolution of imaging lesions. We analyzed the course and the examination results of the patient and speculated the cause and pathogenesis. RESLES-relevant knowledge was systematically reviewed, which will help doctors in the classification of cerebral function and the diagnosis of RESLES. The specific language and cognitive impairment may be associated with the damage of contact fibers in the bilateral primary and secondary sensory and motor cortices.

Membrane protein biogenesis poses acute challenges to protein homeostasis, and how they are selectively escorted to the target membrane is not well understood. Here we address this question in the guided-entry-of-tail-anchored protein (GET) pathway, in which tail-anchored membrane proteins (TAs) are relayed through an Hsp70-Sgt2-Get3 chaperone triad for targeting to the endoplasmic reticulum. We show that the Hsp70 ATPase cycle and TA substrate drive dimeric Sgt2 from a wide-open conformation to a closed state, in which TAs are protected by both substrate binding domains of Sgt2. Get3 is privileged to receive TA from closed Sgt2, whereas off-pathway chaperones remove TAs from open Sgt2. Sgt2 closing is less favorable with suboptimal GET substrates, which are rejected during or after the Hsp70-to-Sgt2 handover. Our results demonstrate how fine-tuned conformational dynamics in Sgt2 enable hydrophobic TAs to be effectively funneled onto their dedicated targeting factor while also providing a mechanism for substrate selection.

The guided entry of tail-anchored protein (GET) pathway, in which the Get3 ATPase delivers an essential class of tail-anchored membrane proteins (TAs) to the Get1/2 receptor at the endoplasmic reticulum, provides a conserved mechanism for TA biogenesis in eukaryotic cells. The membrane-associated events of this pathway remain poorly understood. Here we show that complex assembly between the cytosolic domains (CDs) of Get1 and Get2 strongly enhances the affinity of the individual subunits for Get3•TA, thus enabling efficient capture of the targeting complex. In addition to the known role of Get1CD in remodeling Get3 conformation, two molecular recognition features (MoRFs) in Get2CD induce Get3 opening, and both subunits are required for optimal TA release from Get3. Mutation of the MoRFs attenuates TA insertion into the ER in vivo. Our results demonstrate extensive cooperation between the Get1/2 receptor subunits in the capture and remodeling of the targeting complex, and emphasize the role of MoRFs in receptor function during membrane protein biogenesis.