Synthesis and Neuromuscular Blocking Activity of 16β-Piperidino Epiandrosterone Derivatives

This study reports the synthesis of steroidal quaternary ammonium compounds 11 and 12, with quaternary nitrogen at position 3 and 16 of the steroid nucleus in 5α-epiandrosterone series; along with their neuromuscular blocking activity using chick biventer cervicis muscle preparation. The compound 12 was found to be five times more potent than 11 in reducing twitch response to nerve stimulations, indicating the importance of extended interonium distances and 17-acetoxy function for potent antagonist activity.     

Comparison of radiographic and magnetic resonance imaging findings of early osteoarthritis of the rabbit knees: an experimental study

The objectives of the present study were to describe radiographic and magnetic resonance imaging (MRI) findings of early osteoarthritis and their relationships at the same time. A total number of ten rabbits were used and randomly divided into two equal groups. In one group, cranial cruciate ligament (CCL) of the left knee was transected to produce experimental osteoarthritis and in the other group, only the articular capsule was entered as sham operation (arthrotomy group). All of the left knees were examined by MRI and radiography before operation to exclude preexisting abnormalities and serve as control. One month postoperation, two conventional radiographic views and MR imaging were performed under general anesthesia. Statistical analysis of the MRI results revealed that there was a significant difference between the CCL-transected group with arthrotomy and control groups. There was no significant difference in the radiographic findings between the operated, arthrotomy and control groups. It was concluded that osteoarthritic changes of the joints can be detectable 1?month postinjury by MRI. Meniscal degeneration and subchondral bone irregularity are detectable diagnostic signs.     

Silver nanoparticles production by two soil isolated bacteria,Bacillus thuringiensis and Enterobacter cloacae,and assessment of their cytotoxicity and wound healing effect in rats

Production of silver nanoparticles by Bacillus thuringiensis and Enterobacter cloacae was performed and confirmed through UV–visible spectrophotometry, transmission electron microscopy (TEM), and x‐ray diffraction (XRD) analyses. The 3‐(4,5‐dimethylthiazol‐2‐yl)?2,5‐diphenyltetrazolium bromide (MTT) assay using mouse fibroblast cell line NIH‐3T3 D4 was carried out and IC_50s of AgNPs were obtained. The nontoxic dose of each AgNPs solution was selected for wound healing assay. Thirty‐two rats were divided into four groups; two were used as the controls and two were treated by AgNPs that were produced by two bacterial strains. Results revealed that the produced AgNPs were amorphous, spherical in shapes, and had sizes under 100 nm. Histological analysis showed that AgNPs had better wound healing efficacy than the control groups. In conclusion, when the biologically produced AgNPs were used in vivo, they induced the epithelization, formation of the collagen bundles and fibroplasia and reduced the duration of completion of the epithelization and the angiogenesis.     

Comparison of hemodynamic responses to nifedipine and nitroprusside in severe chronic congestive heart failure

The hemodynamic effects of 20 to 40 mg of oral nifedipine were compared with those of intravenous nitroprusside in 11 patients with severe chronic congestive heart failure (CHF). In each patient, both drugs were administered to produce similar reduction of systemic vascular resistance (SVR) (29 ± 13% with nifedipine and 29 ± 12% with nitroprusside, difference not significant [NS]). At this comparable decrease in systemic vascular resistance, significant differences in hemodynamic responses to both drugs were noted: Nifedipine caused a smaller increase in cardiac index (20 ± 20% vs 40 ± 24%, p < 0.02) and a larger decrease in mean blood pressure than nitroprusside (16 ± 9% vs 8 ± 10%, p < 0.05). In addition, nifedipine produced a smaller decrease in mean pulmonary artery wedge pressure (13 ± 24% vs 36 ± 21%, p < 0.001) and pulmonary vascular resistance than nitroprusside (6 ± 42% vs 26 ± 46%, NS. Mean right atrial pressure decreased with nitroprusside, from 10 ± 7 to 5 ± 3 mm Hg (p < 0.05), but not with nifedipine (10 ± 7 mm Hg before and after nifedipine administration, NS). Left ventricular stroke work index increased with nitroprusside (20 ± 8 to 27 ± 9 g-m/m², p < 0.05), but did not change with nifedipine (21 ± 9 vs 21 ± 10 g-m/m², NS). These data show that nifedipine has an arteriolar dilatatory action in patients with CHF. However, compared with nitroprusside, nifedipine had a significantly larger hypotensive effect and had a lesser effect on right and left ventricular filling pressure, cardiac output and left ventricular function.     

Selective photocatalytic oxidation of aromatic alcohols to aldehydes with air by magnetic WO3ZnO/Fe3O4. In situ photochemical synthesis of 2-substituted benzimidazoles

Recently, visible light-driven organic photochemical synthesis has been a pioneering field of interest from academic and industrial associations due to its unique features of green and sustainable chemistry. Herein, WO₃ZnO/Fe₃O₄ was synthesized, characterized, and used as an efficient magnetic photocatalyst in the preparation of a range of 2-substituted benzimidazoles via the condensation of benzyl alcohol and o-phenylenediamine in ethanol at room temperature for the first time. The key feature of this work is focused on the in situ photocatalytic oxidation of benzyl alcohols to benzaldehydes under atmospheric air and in the absence of any further oxidant. This new heterogeneous nanophotocatalyst was characterized via XRD, FT-IR, VSM and SEM. Short reaction time, cost-effectiveness, broad substrate scope, easy work-up by an external magnet, and excellent product yield are the major advantages of the present methodology. A number of effective experimental parameters were also fully investigated to clear broadness and generality of the protocol.

WO₃ZnO/Fe₃O₄ is used as a magnetic photocatalyst in the preparation of 2-substituted benzimidazoles in EtOH at RT. The key feature is the in situ photocatalytic oxidation of benzyl alcohols to benzaldehydes under atmospheric air in the absence of further oxidant.     

Finite element analysis of lordosis restoration with anterior longitudinal ligament release and lateral hyperlordotic cage placement

Purpose

Restoring sagittal alignment is an important factor in the treatment of spinal deformities. Recent investigations have determined that releasing the anterior longitudinal ligament (ALL) and placing hyperlordotic cages can increase lordosis, while minimizing need for 3 column osteotomies. The influences of parameters such as cage height and angle have not been determined. Finite element analysis was employed to assess the extent of lordosis achievable after placement of different sized lordotic cages.

Methods

A 3-dimensional model of a L3–4 segment was used. Disc distraction was simulated by inserting interbody cages mid-body in the disc space. Analyses were performed in the following conditions: (1) intact, (2) ALL release, (3) ALL release + facetectomy, and (4) ALL release + posterior column osteotomy. Changes in segmental lordosis, disc height, foraminal height, and foraminal area were measured.

Results

After ALL resection and insertion of hyperlordotic cages, lordosis was increased in all cases. The lordosis achieved by the shorter cages was less due to posterior disc height maintained by the facet joints. A facetectomy increased segmental lordosis, but led to contact between the spinous processes. For some configurations, a posterior column osteotomy was required if the end goal was to match cage angle to intradiscal angle.

Conclusion

Increased segmental lumbar lordosis is achievable with hyperlordotic cages after ALL resection. Increased cage height tended to increase the amount of lordosis achieved, although in some cases additional posterior bone resection was required to maximize lordosis. Further studies are needed to evaluate the impact on regional lumbar lordosis.

     

Successful Fixation of an Intertrochanteric Fracture After Hip Resurfacing Arthroplasty Using Cannulated Screws

We report a case of successful treatment of a high, stable intertrochanteric fracture (type 1) in a 59-year-old man. He sustained the injury 8 years after the resurfacing procedure. The fracture was fixed using three 6.5-mm cannulated screws, and he has returned to his normal level of activities 8 months after the fixation. We have shown that fixation with cannulated screws may be an acceptable option for treatment of high trochanteric fractures where a stable anatomical reduction can be obtained. We have also included a review of the literature for other reported surgical treatment options of this complication.