Improved intervertebral fusion in LLIF rabbit model with a novel titanium cage.

BACKGROUND CONTEXT: There is no established small animal approach model for the strict simulation of lateral lumbar interbody fusion (LLIF) surgery. PURPOSE: This study aims to establish a reliable LLIF rabbit model that strictly simulates the procedure and to preliminarily evaluate the differences in fusion outcomes with different graft materials. STUDY DESIGN: A controlled laboratory. METHODS: Fifty-four 4-month-old white New Zealand female and male rabbits were selected and divided into five groups: Group A (dissection group) consisted of 9 rabbits, Group B (normal approach group) consisted of 9 rabbits, Group C (autogenous iliac bone group) consisted of 12 rabbits, Group D (BMP-2 carrier material group) consisted of 12 rabbits, and Group E (allograft bone group) consisted of 12 rabbits. Based on data from Group A, a novel titanium metal fusion device was designed. Postoperatively, at the 12-week mark, manual palpation was employed to compare the interbody fusion status among Groups B, C, D, and E. Specimens from Groups C, D, and E were subjected to Micro-CT scanning to compare various parameters such as trabecular bone volume (BV), bone volume fraction (BV/TV, BVF), and bone surface area (BS). Furthermore, a tissue histopathological examination was performed to observe the structure and morphology of newly formed bone within the fusion mass as well as the remodeling of the graft in each group. RESULTS: Based on the measurements obtained from the dissection group, we designed a U-shaped interbody fusion device with dimensions of 10 mm in length, 2.5 mm in width, and 1.3 mm in height. In Group B, 9 cases exhibited intervertebral mobility. In Group C, 1 case showed nonfusion. In Group D, all cases achieved fusion. In Group E, 4 cases did not achieve fusion. Additionally, the Micro-CT results showed that the interbody fusion index scores were 4.64±0.50 in Group C, 4.33±0.65 in Group D, and 3.36±0.81 in Group E. There was no statistically significant difference in fusion index scores between Groups C and D (p=.853). Notably, Groups C and D had higher scores than Group E (p<.001). The trabecular bone volume (BV) in Groups C and D also showed no significant difference but was significantly higher than in Group E (p<.001). Furthermore, the histopathological results revealed that the specimens from Group E had less newly formed cartilage and bone compared to Groups C and D. CONCLUSIONS: This study successfully established a strict simulation of the clinical LLIF procedure in a rabbit model. Moreso, we conducted a preliminary validation indicating that the BMP-2 carrier material achieved interbody fusion outcomes similar to autogenous iliac bone. CLINICAL SIGNIFICANCE: The findings of this investigation from animal models provide a theoretical basis for the clinical use of BMP-2 to promote early spinal fusion in LLIF procedures. Importantly, the study provides a small animal model foundation for research related to LLIF surgery.

A de novo homozygous missense mutation of the GUSB gene leads to mucopolysaccharidosis type VII identification in a family with twice adverse pregnancy outcomes due to non-immune hydrops fetalis.

Non-immune hydrops fetalis (NIHF) is a common and severe manifestation of many genetic disorders. The ultrasound is an ideal method for diagnosing hydrops fetalis during pregnancy. Since most NIHFs do not have an identifiable cause, determining the underlying etiology remains a challenge for prenatal counseling. Due to advancements in exome sequencing, the diagnostic rates of NIHF have recently increased. As reported here, DNA was extracted from the amniotic fluid of a pregnant woman who was prenatally diagnosed with a NIHF type of unclear origin. Amniocentesis sampling demonstrated a normal female karyotype and copy number variation(CNVs) without alterations. Tri-whole exome sequencing (WES) was conducted to identify possible causative variants. In the fetus, a de novo genetic mutation was identified as a homozygous form. The mutation was located on the glucuronidase beta (GUSB) gene: NM_000181.3: c.1324G > A; p. Ala442Thr; Chr7:65439349, which leads to mucopolysaccharidosis type VII. This mutation was inherited from the parents and was first reported to be related to NIHF. We conclude that the use of WES is beneficial for NIHF cases whose prognosis has not been explained by standard genetic testing.

Radio frequency ablation for the intrauterine treatment of giant placental chorioangioma associated with fetal compromise: A case report.

Giant placental chorioangiomas associated with fetal hyperdynamic circulation complications are rare to see. Here, we summarized a case of giant placental chorioangioma associated with fetal anemia and heart failure treated by radiofrequency ablation (RFA) combined with cordocentesis and intrauterine transfusion. The sonographic appearance of the placental chorioangioma was atypical which was isoechoic with unclear boundary. RFA was performed successfully at 27 weeks of gestation, when the chorioangioma has increased to 17.0 × 10.6 × 12.3 cm3 . Unfortunately, intrauterine fetal demise was found on the first day after operation. After induction of labor, it was pathologically confirmed as placental chorioangioma.

Microstructure and Mechanical Properties of Nanocrystalline Al-Zn-Mg-Cu Alloy Prepared by Mechanical Alloying and Spark Plasma Sintering.

In this study, Al, Zn, Mg and Cu elemental metal powders were chosen as the raw powders. The nanocrystalline Al-7Zn-2.5Mg-2.5Cu bulk alloy was prepared by mechanical alloying and spark plasma sintering. The effect of milling time on the morphology and crystal structure was investigated, as well as the microstructure and mechanical properties of the sintered samples. The results show that Zn, Mg and Cu alloy elements gradually dissolved in α-Al with the extension of ball milling time. The morphology of the ball-milled Al powder exhibited flaking, crushing and welding. When the ball milling time was 30 h, the powder particle size was 2-5 µm. The α-Al grain size was 23.2 nm. The lattice distortion was 0.156% causing by the solid solution of the metal atoms. The grain size of ball-milled powder grew during the spark plasma sintering process. The grain size of α-Al increased from 23.2 nm in the powder to 53.5 nm in the sintered sample during the sintering process after 30 h of ball milling. At the same time, the bulk alloy precipitated micron-sized Al2Cu and nano-sized MgZn2 in the α-Al crystal. With the extension of ball milling time, the compression strength, yield strength and Vickers hardness of spark plasma sintering (SPS) samples increased, while the engineering strain decreased. The compression strength, engineering strain and Vickers hardness of sintered samples prepared by 30 h milled powder were ~908 MPa, ~8.1% and ~235 HV, respectively. The high strength of the nanocrystalline Al-7Zn-2.5Mg-2.5Cu bulk alloy was attributed to fine-grained strengthening, dislocation strengthening and Orowan strengthening due to the precipitated second phase particles.

The application of deep eutectic solvent on the extraction and in vitro antioxidant activity of rutin from Sophora japonica bud.

The extraction conditions and antioxidant activities of rutin from Sophora japonica bud by deep eutectic solvents were investigated. Box-Behnken design was used to optimize the extraction conditions and the scavenging activities of DPPH, O2- and ·OH of purified rutin were evaluated. The highest yield of 279.8 mg/g was achieved in the extraction medium of choline chloride/triethlene glycol (1/4) under the optimum conditions: water content of the DES 18.1%, extraction time 28.3 min, extraction temperature 70 °C and liquid-solid ratio 10 mg/1 g. The highest extraction amount was slightly different from the predicted value of the established second-order polynomial equation. In addition, The EC50 of DPPH scavenging, O2- scavenging and ·OH scavenging of rutin were 5.68 µg/mL, 0.19 and 0.28 mg/mL, respectively. The above results indicate rutin extracted by the choline chloride/triethylene glycol has excellent antioxidant activity and was an admirable free radical scavenger.