Semaphorin3A promotes osseointegration of titanium implants in osteoporotic rabbits.

OBJECTIVE: In the present study, we intend to assess the function of Sema3A in osteointegration of titanium implants both in vivo and in vitro. MATERIAL AND METHODS: Briefly, Sema3A was transfected in HBMSCs cells to detect its effect on osteogenesis. Subsequently, an in vivo rabbit model was established. Eighteen female rabbits were randomly assigned into three groups (n=6), and rabbits in the two treatment groups (OVX groups) were subjected to bilateral ovariectomy, while those in the control group were treated with sham operation. Twelve weeks later, we first examined expression levels of Sema3A in rabbits of the three groups. Titanium implants were implanted in rabbit proximal tibia. Specifically, rabbits in sham group were implanted with Matrigel, while the remaining in the OVX experimental group (OVX+Sema3A group) and OVX group were implanted with Matrigel containing Sema3A adeno-associated virus or empty vector, respectively. RESULTS: Histomorphometry results uncovered that rabbits in the OVX+Sema3A group had a significantly higher BIC compared with those of the OVX group on the 12th week of post-implantation. And compared with the OVX group, the maximum push-out force increased by 89.4%, and the stiffness increased by 39.4%, the toughness increased by 63.8% in the OVX+Sema3A group at 12 weeks. CONCLUSION: Sema3A has a positive effect on promoting early osseointegration of titanium implants in osteoporotic rabbits. CLINICAL RELEVANCE: Our research found that Sema3A can improve the osteogenic ability of bone marrow stem cells and promotes osseointegration during osteoporosis.

Aggregation-induced fluorescence of the luminol-terbium(III) complex in polymer nanoparticles for sensitive determination of thrombin.

A fluorometric method is described for the determination of thrombin. Polymer nanoparticles containing the luminol-terbium(III) complex (luminol-Tb) were prepared where luminol acts as the bridging ligand, and Tb(III) acts as the central metal ion. Thrombin possesses a large number of electrons donating groups that coordinate with luminol-Tb. Following coordination, the rigidity of the linker is increased, and this decreases the non-radiative decay rate and induces an increase in fluorescence intensity at 430 nm. Hence, thrombin can be fluorometrically determined. The detection limit of thrombin is as low as 3.5 pM (at an SNR of 3). This is about 10 times lower than assays using an aptamer. The method was applied in the determination of thrombin in human serum via the standard addition method and gave satisfying results. Graphical abstractSchematic representation of the preparation of the luminol-Tb(III) complex in a nanoparticle host by the self-assembly of luminol and Tb(III) ions. Thrombin readily coordinates with the luminol-Tb(III) system, and this results in particle aggregation. The blue fluorescence of luminol increases strongly, and this effect provides the basis for fluorometric determination of thrombin.

Surgical management of spinal metastases of thymic carcinoma: A case report and literature review.

RATIONALE: Metastatic thymic carcinoma in the spine is a rare disease with no standard curative managements yet. The objective of this study is to report a very rare case of spinal metastases of thymic carcinoma successfully operated by combination of instrumentation and cement augmentation together with adjuvant treatment. The management of these unique cases has yet to be well-documented. PATIENT CONCERNS: A 57-year-old man presented with a 6-month history of continuous and progressive back pain. The patient, who had been diagnosed of thymic carcinoma (stage IV B) for 3 years, received surgical treatment of median sternotomy thymectomy, followed by 3 cycles of chemotherapy and 12 cycles of radiotherapy. DIAGNOSIS: Magnetic resonance imaging (MRI) of spine showed spinal cord compression secondary to the epidural component of the T4 mass, with increased metastatic marrow infiltration of the left T4 vetebral body, which presented as a solid tumor. Post-operative pathology confirmed the diagnosis of spinal metastases of thymic carcinoma. INTERVENTIONS: The patient underwent exploratory surgery, circumferential spinal cord decompression, cement augmentation and a stabilization procedure via a posterior approach. OUTCOMES: The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 3-month follow-up visit. There were no other complications associated with the operation during the follow-up period. LESSONS: Taken together, the lesion's clinical features, imaging results, and pathological characteristics are unique. Combined efforts of specialists from orthopedics, neurosurgery, thoracic surgery, and medical oncology led to the successful diagnosis and management of this patient. Metastatic thymic carcinoma of the spine, although rare, should be part of the differential diagnosis when the patient has a history of thymic carcinoma and presents with back pain and radiculopathy. We recommend the posterior approach for spinal decompression of the metastatic thymic carcinoma when the tumor has caused neurological deficits. Osteoplasty by cement augmentation is also a good choice for surgical treatment.

Successful treatment of Gorham-Stout syndrome in the spine by vertebroplasty with cement augmentation: A case report and literature review.

RATIONALE: Gorham-Stout syndrome in the spine is extremely rare, and there is no standard curative management thus far. The objective of this article is to report a very rare case of Gorham-Stout syndrome of the lumbar and sacral spine with chylothorax and chyloperitoneum successfully treated by combination of vertebroplasty with cement augmentation and medication treatment. We described the clinical characteristics and postoperative therapy of the patient, and reviewed all of the published cases of Gorham-Stout syndrome of the lumbar and sacral spine. PATIENT CONCERNS: A 31-year-old man presented with increasingly serious abdominal distention and back pain. MRI showed massive bony destruction of the spine and pelvis. CT and ultrasonography demonstrated massive ascites and mild hydrothorax. DIAGNOSES: We believe this is the first report of a case of Gorham-Stout syndrome with both chylothorax and chyloperitoneum. INTERVENTIONS: Chest and abdominal cavity puncture was performed for symptomatic relief and the test results confirmed chylothorax and chyloperitoneum. Tissue biopsy and percutaneous vertebroplasty at L5 were performed and the postoperative pathology together with symptoms and examinations were reported to be consistent with Gorham-Stout syndrome. Subsequently, we administered combination medical treatment consisting of interferon-α-2b, zoledronic acid and calcitriol. OUTCOMES: At the 1-year and 2-year follow-up visit, he had nearly full complete remission and reported palliative back pain. Moreover, the amount of pleural and peritoneal fluid was successfully reduced gradually. LESSONS: Vertebroplasty by cement augmentation may be a treatment option for patients with Gorham-Stout Syndrome in the spine who cannot undergo appropriate surgery or decline open surgery. This represents a safe and minimally invasive approach to sustainably relieve pain and stabilize vertebral bodies with Gorham-Stout syndrome in the spine.

Biological pretreatment of corn stover with ligninolytic enzyme for high efficient enzymatic hydrolysis.

Aiming at increasing the efficiency of transferring corn stover into sugars, a biological pretreatment was developed and investigated in this study. The protocol was characterized by the pretreatment with crude ligninolytic enzymes from Phanerochete chrysosporium and Coridus versicolor to break the lignin structure in corn stover, followed by a washing procedure to eliminate the inhibition of ligninolytic enzyme on cellulase. By a 2 d-pretreatment, sugar yield from corn stover hydrolysis could be increased by 50.2% (up to 323 mg/g) compared with that of the control. X-ray diffractometry and FT-IR analysis revealed that biological pretreatment could partially remove the lignin of corn stover, and consequently enhance the enzymatic hydrolysis efficiency of cellulose and hemeicellulose. In addition, the amount of microbial inhibitors, such as acetic acid and furfural, were much lower in biological pretreatment than that in acid pretreatment. This study provided a promising pretreatment method for biotransformation of corn stovers.