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Objective To focus on the efficacy at variable frequency stimulation (VFS) after deep brain stimulation (DBS) for the treatment of axial symptoms in Parkinson's disease (PD). Methods Clinical data of 12 patients with PD who underwent bilateral DBS followed by VFS more than one year from January 2018 to June 2022 at Tianjin Huanhu Hospital, Tianjin University were retrospectively analyzed. Axial symptoms were assessed using Unified Parkinson's Disease Rating Scale (UPDRS)-gait posture, Timed Up and Go Test (TUGT) time and the occurrence of freezing of gait (FOG), The Freezing of Gait - Questionnaire (FOG - Q), and Berg Balance Scale (BBS). The above indicators were recorded one week before DBS surgery and in the drug "off" period (baseline), at the end of high frequency stimulation (the end of HFS), at one month follow-up of VFS (short-term VFS), and at one year or more follow-up of VFS (long-term VFS). Results Compared with baseline, BBS scores increased at the end of HFS (t = - 2.845, P = 0.008); UPDRS-gait posture (t = 12.703, P = 0.000; t = 11.737, P = 0.000), TUGT time (t = 8.923, P = 0.000; t = 8.025, P = 0.000) and the occurrence of FOG (t = 4.448, P = 0.000; t = 4.181, P = 0.000), and FOGQ scores (t = 9.186, P = 0.000; t = 8.186, P = 0.000) decreased, while the BBS scores increased (t = - 7.686, P = 0.000; t = - 6.106, P = 0.000) in both short-term VFS and long-term VFS. Compared with the end of HFS, UPDRS-gait posture (t = 11.583, P = 0.000; t = 10.618, P = 0.000), TUGT time (t = 6.922, P = 0.000; t = 6.022, P = 0.000) and the occurrence of FOG (t = 3.612, P = 0.001; t = 3.344, P = 0.002), and FOG-Q scores (t = 7.915, P = 0.000; t = 6.915, P = 0.000) decreased, while the BBS scores increased (t = - 4.842, P = 0.000; t = - 3.262, P = 0.003) in short-term VFS and long-term VFS. Conclusions For PD patients with HFS but poor axial symptoms efficacy after DBS, the use of VFS significantly improves multifaceted axial symptoms with reliable long-term efficacy.

Parkinson's disease (PD) is a complex, chronic and progressive neurodegenerative disease. When medication doesn't work well, surgical treatments should be considered to improve symptoms. Currently, surgical treatments to PD include not only neurosurgical ablation with different principles, such as radiofrequency ablation (RFA), magnetic resonance guided laser interstitial thermal therapy (MRgLITT), magnetic resonance guided focused ultrasound (MRgFUS) and stereotactic radiotherapy (SRT), but also neuromodulation techniques including deep brain stimulation (DBS). In addition, spinal cord stimulation (SCS), gene and transplantation therapy to PD are also being explored. This review focuses on advances of above treatments of PD, and analyzes their efficacy and safety in order to provide more theory and basis for clinical researchs.

Objective To investigate the therapeutic effect of deep brain stimulation (DBS) on non⁃motor symptoms of Parkinson's disease (PD). Methods A total of 41 patients with PD who underwent DBS in Tianjin Huanhu Hospital from January 2015 to January 2021 were selected as subjects. The cognitive function was assessed by Mini⁃Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) at 3, 6 and 12 months after operation. Beck Depression Inventory Ⅱ (BDI⁃Ⅱ) and Hamilton Anxiety Rating Scale (HAMA) assessed depression and anxiety, Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) assessed sleep disorders and sleepiness, and Unified Parkinson's Disease Rating Scale Ⅲ (UPDRSⅢ) assessed motor symptoms. Levodopa equivalent daily dose (LEDD) was used to assess postoperative dependence on anti⁃PD drugs. Results The BDI⁃Ⅱscore (P=0.000), HAMA total scores (P=0.000) and its somatic anxiety (P=0.000), mental anxiety (P=0.000), PSQI total scores (P=0.000) and its subjective sleep quality (P=0.000), time to fall asleep (P=0.000), sleep duration (P=0.000), sleep efficiency (P=0.000), sleep disorders (P=0.000), sleep drug use (P=0.015), daytime dysfunction (P=0.000), ESS score (P=0.000), UPDRSⅢ score (P=0.000) and LEDD (P=0.000) had statistically significant differences before and after surgery. The improvement rates of BDI⁃Ⅱ, HAMA, PSQI and ESS were 46.00%, 33.58%, 34.67% and 34.30%, 49.69%, 35.01%, 38.19% and 36.20%, 50.51%, 35.24%, 39.77% and 39.44% at 3, 6 and 12 months after surgery respectively. The scores at different postoperative observation points were significantly different from those before surgery (P＜0.01, for all). However, there were no significant differences in MMSE total scores and its score of orientation, memory, attention and computation, recall ability and language function, as well as MoCA total scores and its score of visual spatial and executive function, naming, attention, language, abstraction, delayed recall and orientation before and after surgery (P＞0.05, for all). Conclusions DBS can significantly improve the motor symptoms, mood and sleep disorder of non⁃motor symptoms (NMS) in PD patients, and reduce the dose of anti⁃PD drugs, but has no effect on cognitive function.

This paper presents a novel wideband dual‐polarized air‐patch antenna with enhanced port isolation. The proposed design consists of a suspended metal patch, two feeding slots, and novel composite decoupling structures (CDS). The CDS is composed of two reactive loads (RLs), an additional square slot (ASS), and two neutralizing lines (NLs). The reactive loads and one NL are connected to the feeding slots. The other NL is connected to the ASS. The CDS plays a critical role in achieving wideband high port isolation. The decoupling principles are illustrated by using a circuit model and through rigorous mathematical derivation. Design evolution of the proposed antenna (Ant 1–5) was carefully explained. Experimental results demonstrate that the proposed antenna has a −15 dB refection coefficient bandwidth covering the frequency range of 3.32–3.67 GHz. Additionally, it exhibits high port isolation (>35 dB), low cross polarization, high gain, and excellent total efficiency (>85%). [ABSTRACT FROM AUTHOR]

In this study, a novel bandpass filter (BPF) characterized by low insertion loss (IL) and the presence of two transmission zeros (TZs) based on integrated passive device (IPD) technology is introduced. The design incorporates a low‐pass filter and a high‐pass filter which both exhibit strong out‐of‐band suppression performance. The control structure for TZs is constructed by cascading the inductance and capacitance components. The TZ controlling structure primarily generates TZs at high frequencies, resulting in a further bandwidth enhancement in the stopband. The lumped circuit of the proposed BPF is first constructed, and rigorous design formulas are provided to assist in constructing the proposed design. After schematic optimization, the second step involves layout optimization and simulation based on the specific IPD process. Experimental results mounted on a printed circuit board demonstrate that the bandwidth spans from 3.3 to 4.2 GHz with an IL of only 2.0 dB at the center frequency. Additionally, this BPF achieves impressive sideband suppression, exceeding 18 dB in the 0–1.7 GHz range and 30 dB in the 9–15 GHz range. Remarkably, the BPF is exceptionally compact with only 0.5 mm × 1.0 mm (0.006λc × 0.012λc). The proposed BPF exhibits outstanding performance with minimal IL and extensive sideband suppression at such a compact size based on the IPD technology. [ABSTRACT FROM AUTHOR]

This paper proposes a decoupling technique with bandwidth enhanced by introducing two transmission zeros based on common mode (CM) and differential mode (DM) cancellation. The mutual coupling between antennas can be thoroughly eliminated if the CM and DM impedances are equal. Two transmission zeros with closely spaced frequencies are created by using a neutralization line and a parasitic element. The neutral line and parasitic unit can change the currents of radiation patches in CM and DM to realize an enhancement of decoupling bandwidth. To demonstrate the feasibility of this method, a reference and proposed arrays are fabricated and measured. In measurement, the port isolation of proposed antenna array is enhanced by 10.3–21.56 dB in the desired frequency band. Besides, the efficiency and gain are improved by 0.5–3 dB and 10.4%–18%, respectively. The pattern diversity/envelop correlation coefficient (ECC) is also enhanced. [ABSTRACT FROM AUTHOR]