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Calcium sulfate and calcium sulfate-based biomaterials have been widely used in non-load-bearing bone defects for hundreds of years due to their superior biocompatibility, biodegradability, and non-toxicity. However, lower compressive strength and rapid degradation rate are the main limitations in clinical applications. Excessive absorption causes a sharp increase in sulfate ion and calcium ion concentrations around the bone defect site, resulting in delayed wound healing and hypercalcemia. In addition, the space between calcium sulfate and the host bone, resulting from excessively rapid absorption, has adverse effects on bone healing or fusion techniques. This issue has been recognized and addressed. The lack of sufficient mechanical strength makes it challenging to use calcium sulfate and calcium sulfate-based biomaterials in load-bearing areas. To overcome these defects, the introduction of various inorganic additives, such as calcium carbonate, calcium phosphate, and calcium silicate, into calcium sulfate is an effective measure. Inorganic materials with different physical and chemical properties can greatly improve the properties of calcium sulfate composites. For example, the hydrolysis products of calcium carbonate are alkaline substances that can buffer the acidic environment caused by the degradation of calcium sulfate; calcium phosphate has poor degradation, which can effectively avoid the excessive absorption of calcium sulfate; and calcium silicate can promote the compressive strength and stimulate new bone formation. The purpose of this review is to review the poor properties of calcium sulfate and its complications in clinical application and to explore the effect of various inorganic additives on the physicochemical properties and biological properties of calcium sulfate.

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BACKGROUND: Muscle structural studies on non-specific low back pain in young female nurses are rare. This study aimed to investigate the changes of lumbar extensor and flexor muscle cross-sectional area and fatty infiltration in young female nurses with chronic bilateral non-specific low back pain by lumbar spine magnetic resonance imaging to speculate on the possible pathogenesis. METHODS: The magnetic resonance imaging (MRI) data of 58 female nurses with chronic bilateral non-specific low back pain and 60 healthy female controls were analyzed retrospectively. The lumbar extensor and flexor muscle cross-sectional area/intervertebral disc cross-sectional area ratio, as well as magnetic resonance imaging signal intensity of lumbar extensor (erector spinae; multifidus) and flexor muscles (psoas muscle) were measured, calculated and compared between nurses and healthy controls by independent samples t-test. In addition, each mean MRI signal intensity of lumbar extensor or flexor muscles in nurses at different anatomical segments from lumbar vertebrae 2 (L2)-L3 to L5-sacral vertebrae 1 (S1) was also compared, and one-way Analysis of Variance (ANOVA) analyzed the mean MRI signal intensity between muscles in nurses with multiple comparisons. RESULTS: There was no significant difference in lumbar extensor and flexor muscle cross-sectional area/intervertebral disc cross-sectional area ratio between nurses with chronic bilateral non-specific low back pain and healthy controls, p > 0.01. The magnetic resonance imaging signal intensity in lumbar extensor and flexor muscle was significantly higher in nurses with chronic bilateral non-specific low back pain than in healthy controls, p < 0.01. The MRI signal intensity of lumbar extensor muscle at the lower lumbar segments was higher than at the upper ones. The magnetic resonance imaging signal intensity of the extensor muscle (erector spinae; multifidus) was significantly higher than that of the flexor muscle (psoas muscle), p < 0.01. CONCLUSIONS: This study showed that young nurses with chronic bilateral non-specific low back pain have lumbar extensor and flexor muscle fatty infiltration without muscle atrophy. We hypothesized that muscle fatty infiltration may occur prior to muscle atrophy. Therefore, the high fatty infiltration of the lumbar extensor and flexor muscle may be a cause or a result of chronic bilateral non-specific low back pain in young nurses.

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PURPOSE: To investigate the potential risk of the retropharyngeal internal carotid artery (RICA) during nasotracheal intubation (NTI). METHODS: We retrospectively surveyed 2028 patients and 90 healthy controls (HC) with neck computed tomography angiography (CTA). The incidence of RICA was analyzed, as well as the correlation between the average minimum carotid-pharyngeal distance (CPD) and the carotid-median plane distance (CMD). We also compared CPD between RICA and HC. RESULTS: RICA was observed in 91 out of the 2028 patients, reaching an incidence of 4.5% (91/2028). RICA in female patients was 65.9% (60/91) compared to 34.1% (31/91) in male patients. The incidence of RICA at nasopharynx (NP), oropharynx (OP), and hypopharynx (HP) was 31.9% (29/91), 61.5% (56/91), and 6.6% (6/91), respectively. The incidence of the mucosal eminence of the posterior wall of the pharynx in RICA was 30.8% (28/91). In 15 cases, RICA caused the pharyngeal cavity to become narrow, with an incidence of 16.5% (15/91). Moreover, CPD and CMD was positively correlated (r = 0.56, p < 0.01). The average minimum CPD of RICA was only 2.25 ± 1.26 mm, which was much shorter than HC (17.62 ± 1.98 mm) (t = 62.46, p < 0.01). Some CPD of RICA was even less than 1 mm, with an incidence of 20.9% (19/91). CONCLUSION: RICA is not uncommon in asymptomatic adults. It is very close to the midline and posterior wall of the pharynx and is more likely to occur in the nasopharynx (NP) and oropharynx (OP). RICA tear is likely to occur during NTI.

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BACKGROUND: Neurovascular compression (NVC) of the trigeminal nerve is associated with trigeminal neuralgia (TN). Some arteries that compress the trigeminal nerve are large, while others are small. This study evaluated the influence of diameter of compression arteries (DCA) on NVC with and without TN using axial diffusivity (AD) and radial diffusivity (RD) of magnetic resonance (MR) imaging. METHODS: Fifty TN patients with unilateral NVC, 50 asymptomatic patients with unilateral NVC, and 50 healthy controls (HC) were divided into three groups (NVC with TN, NVC without TN, and HC). The three groups were imaged with a 3.0-T MR system using three-dimensional fast imaging employing steady-state acquisition (3D FIESTA) and diffusion tensor imaging (DTI). We compared the mean size of DCA between NVC with and without TN. The mean values of AD and RD at the site of NVC were compared between the three groups. Correlation analyses were performed between the DCA and the diffusion metrics (AD and RD) in NVC patients with and without TN. RESULTS: The mean DCA in NVC patients with TN (1.58 ± 0.34 mm) was larger than that without TN (0.89 ± 0.29 mm). Compared with NVC without TN and HC, the mean values of RD at the site of NVC with TN were significantly increased; however, no significant changes of AD were found between the groups. Correlation analysis showed that DCA positively correlated with RD in NVC patients with and without TN (r = 0.830, p = 0.000). No significant correlation was found between DCA and AD (r = 0.178, p = 0.077). CONCLUSIONS: Larger-diameter compression arteries may increase the chances of TN, and may be a possible facilitating factor for TN.

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Pancreatic cancer is a devastating disease characterized by low sensitivity to conventional chemotherapeutic treatment that has a poor prognosis. Therefore, novel effective chemotherapeutic regimens need to be developed. In this study, we analyzed the combined cytotoxic effect of triptolide and hydroxycamptothecin (HCPT) on pancreatic cancer cell line PANC-1 by using 3-(4.5-dimethylthiazol-2-yl)-5-(3-carboxy-methoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) and fluorescence- activated cell sorting (FACS) assays. Our results showed that the sensitivity of a combined therapy using triptolide and HCPT was higher than that of triptolide or HCPT alone and that activation of caspase-9/caspase-3 and inhibition of nuclear factor-kappaB (NF-κB) signaling pathway may contribute to the synergistic cytotoxic effect of this combination therapy. Therefore, our observations provided evidence supporting the clinical applications of the combination chemotherapy using triptolide and HCPT for treating pancreatic cancer.

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OBJECTIVE: To observe the effect of sorphoridine (SR) on electroencephalograph (EEG) and ethological changes as well as neurons ultrastructure alterations in CA3 of hippocampus in rats. METHODS: Tiny electrodes were embedded into hippocampus of male SD rats. The EEG and behavior changes were observed simultaneously and ultrastructure of morphological deformation of neurons in CA3 of hippocampus were observed with electron microscope at 0.5, 1.5, 8 hours after SR were injected intraperitoneally on freely moving rats. RESULTS: There were no epileptiform discharges and seizure activities observed in control group. There was no abnormality seen on neuron in hippocampus of CA3 in control group. While there were epileptiform discharges and convulsions observed simultaneously when SR were administrated at the dose of 55 mg/kg intraperitoneally. 0.5, 1.5, 8 hours after SR, mitochondrion showed swelling cristae and ruptured membrane. Organelle burst and degeneration of synapses were seen with electromicroscope in CA3 of hippocampus ,especially at 1.5 hours after SR administration. CONCLUSION: Sophoridine can induce acute seizure activity on rats and cause mitochondrion ultrastructural damage. The ultrastructural damage of mitochondrion occurs in the early period after SR administration. It indicates that the injury of mitochondria could be critical in neuron damage caused by sorphoridine.

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The molecular electronegativity-distance vector (MEDV) was used to describe the chemical structural characterization of 46 components of essential oils in the flower of Rosa banksiae. Various multiple linear regression (MLR) models were created with variable screening by the stepwise multiple regression technique and statistics. The QSRR models of 10 and 6 variables were built by MLR with the correlation coefficients (R) of molecular modeling being 0.906 and 0.903. Cross-validation of the models, which contain selected vectors were performed by leave-one -out procedure (LOO) and the satisfied results with correlation coefficients (Rcv) of 0.904 and 0.903, respectively. The results showed that the models constructed can provide estimation stability and favorable predictive ability.

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