Evaluating effectiveness and safety of combined percutaneous transhepatic gallbladder drainage and laparoscopic cholecystectomy in acute cholecystitis patients: Meta-analysis.

BACKGROUND: Acute cholecystitis (AC) is a common disease in general surgery. Laparoscopic cholecystectomy (LC) is widely recognized as the "gold standard" surgical procedure for treating AC. For low-risk patients without complications, LC is the recommended treatment plan, but there is still controversy regarding the treatment strategy for moderate AC patients, which relies more on the surgeon's experience and the medical platform of the visiting unit. Percutaneous transhepatic gallbladder puncture drainage (PTGBD) can effectively alleviate gallbladder inflammation, reduce gallbladder wall edema and adhesion around the gallbladder, and create a "time window" for elective surgery. AIM: To compare the clinical efficacy and safety of LC or PTGBD combined with LC for treating AC patients, providing a theoretical basis for choosing reasonable surgical methods for AC patients. METHODS: In this study, we conducted a clinical investigation regarding the combined use of PTGBD tubes for the treatment of gastric cancer patients with AC. We performed searches in the following databases: PubMed, Web of Science, EMBASE, Cochrane Library, China National Knowledge Infrastructure, and Wanfang Database. The search encompassed literature published from the inception of these databases to the present. Subsequently, relevant data were extracted, and a meta-analysis was conducted using RevMan 5.3 software. RESULTS: A comprehensive analysis was conducted, encompassing 24 studies involving a total of 2564 patients. These patients were categorized into two groups: 1371 in the LC group and 1193 in the PTGBD + LC group. The outcomes of the meta-analysis revealed noteworthy disparities between the PTGBD + LC group and the LC group in multiple dimensions: (1) Operative time: Mean difference (MD) = 17.51, 95%CI: 9.53-25.49, P < 0.01; (2) Conversion to open surgery rate: Odds ratio (OR) = 2.95, 95%CI: 1.90-4.58, P < 0.01; (3) Intraoperative bleeding loss: MD = 32.27, 95%CI: 23.03-41.50, P < 0.01; (4) Postoperative hospital stay: MD = 1.44, 95%CI: 0.14-2.73, P = 0.03; (5) Overall postoperative complication rate: OR = 1.88, 95%CI: 1.45-2.43, P < 0.01; (6) Bile duct injury: OR = 2.17, 95%CI: 1.30-3.64, P = 0.003; (7) Intra-abdominal hemorrhage: OR = 2.45, 95%CI: 1.06-5.64, P = 0.004; and (8) Wound infection: OR = 0. These findings consistently favored the PTGBD + LC group over the LC group. There were no significant differences in the total duration of hospitalization [MD = -1.85, 95%CI: -4.86-1.16, P = 0.23] or bile leakage [OR = 1.33, 95%CI: 0.81-2.18, P = 0.26] between the two groups. CONCLUSION: The combination of PTGBD tubes with LC for AC treatment demonstrated superior clinical efficacy and enhanced safety, suggesting its broader application value in clinical practice.

Optical non-reciprocity induced by asymmetrical dispersion of Tamm plasmon polaritons in terahertz magnetoplasmonic crystals.

Nonreciprocal light phenomena, including one-way wave propagation along an interface and one-way optical tunneling, are presented at terahertz frequencies in a system of magnetically controlled multi-layered structure. By varying the surface termination and the surrounding medium, it is found that the nonreciprocal bound or radiative Tamm plasmon polartions can be supported, manipulated, and well excited. Two different types of contributions to the non-reciprocity are analyzed, including the direct effect of magnetization-dependent surface terminating layer as well as violation of the periodicity in truncated multi-layered systems. Calculations on the asymmetrical dispersion relation of surface modes, field distribution, and transmission spectra through the structure are employed to confirm the theoretical results, which may potentially impact the design of tunable and compact optical isolators.

Electrical tunability due to coalescence of exceptional points in parity-time symmetric waveguides.

We demonstrate theoretically the electric tunability due to the coalescence of exceptional points in PT-symmetric waveguides bounded by imperfect conductive layers. Owing to the competition effect of multimode interaction, multiple exceptional points and PT phase transitions could be attained in such a simple system, and their occurrences are strongly dependent on the boundary conductive layers. When the conductive layers become very thin, it is found that the oblique transmittance and reflectance of the same system can be tuned between zero and one by a small change in the carrier density. The results may provide an effective method for fast tuning and modulation of optical signals through electrical gating.

Broadband Focusing Acoustic Lens Based on Fractal Metamaterials.

Acoustic metamaterials are artificial structures which can manipulate sound waves through their unconventional effective properties. Different from the locally resonant elements proposed in earlier studies, we propose an alternate route to realize acoustic metamaterials with both low loss and large refractive indices. We describe a new kind of acoustic metamaterial element with the fractal geometry. Due to the self-similar properties of the proposed structure, broadband acoustic responses may arise within a broad frequency range, making it a good candidate for a number of applications, such as super-resolution imaging and acoustic tunneling. A flat acoustic lens is designed and experimentally verified using this approach, showing excellent focusing abilities from 2 kHz and 5 kHz in the measured results.

One-way optical tunneling induced by nonreciprocal dispersion of Tamm states in magnetophotonic crystals.

We show that optical Tamm states (OTSs) with nonreciprocal dispersion can be formed at the boundary separating two different magnetophotonic crystals magnetized in the Voigt geometry. At the frequencies of the Tamm states, one-way optical tunneling can be achieved. The nonreciprocity features of OTSs originate from the simultaneous violation of reciprocity, time-reversal, and all related spatial symmetries in the system. Our predictions are confirmed by the nonreciprocal dispersion of interface modes, unidirectional transmission spectra, and field distributions for our system. Such theoretical results may provide a mechanism to create compact optical isolators.

Super-resolution image transfer by a vortex-like metamaterial.

We propose a vortex-like metamaterial device that is capable of transferring image along a spiral route without losing subwavelength information of the image. The super-resolution image can be guided and magnified at the same time with one single design. Our design may provide insights in manipulating super-resolution image in a more flexible manner. Examples are given and illustrated with numerical simulations.

Subwavelength image manipulation through an oblique layered system.

We show in this work an oblique layered system that is capable of manipulating two dimensional subwavelength images. Through properly designed planar layered system, we demonstrate analytically that lateral image shift could be achieved with subwavelength resolution, due to the asymmetry of the dispersion curve of constant frequency. Further, image rotation with arbitrary angle, as well as image magnification could be generated through a concentric geometry of the alternating layered system. In addition, we verify the image mechanism using full wave electromagnetic (EM) simulations. Utilizing the proposed layered system, optical image of an object with subwavelength features can be projected allowing for further optical processing of the image by conventional optics.

Hard and soft tissue changes following the treatment of Class II division 1 malocclusion using twin-block appliance / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the hard and soft tissue changes following the treatment of Class II division 1 malocclusion using Twin-block appliance.</p><p><b>METHODS</b>50 Class II division 1 malocclusion subjects whose handwrist radiographs were in FG-G stage were selected. One group (27 patients) was treated with Twin-block appliance, the other group (23 patients) was observed without treatment The acquired data of cephalometric of two groups were analyzed statistically with SPSS 11.0.</p><p><b>RESULTS</b>Soft tissue changes, Ls-E, Li-E, U1-Stms, Stms-Stmi, NsLs-FH, LsNsLi, LsNsPg', the angle of H decreased. Sn-Stms, Stmi-Me', Ns-Me', Sn-Me', NsLi-FH, NsPg'-FH, A'Ls-FH, B'Li-FH, LiB' Pg', CmSnLs, GSnPg', the angle of Z increased, there was statistically significant difference (P < 0.05). Hard tissue changes, SNB, L1-NB, IMPA increased, ANB, U1-SN, U1-NA, FMIA decreased, there was statistically significant difference (P < 0.05).</p><p><b>CONCLUSION</b>Sagittal relationship between upper- and lower-jaws is effectively improved after orthopedics with Twin-block appliance. Lower face height increases. Soft tissue profile tends to be straight-styled.</p>