Multilocus sequence typing and antibiotic resistance of Aeromonas isolated from freshwater fish in Hebei Province.

Aeromonas spp. are the opportunistic pathogens that infect both aquatic and terrestrial homeotherms. They were commonly present in aquatic environments, including effluent, tap water, marine, river, and lake, where they are often isolated from aquatic animals, including fish, molluscs, and crustaceans. The Aeromonas infections can cause sepsis, ulcer, and other symptoms, resulting in the death of massive aquatic animals. Therefore, the prevention and control of Aeromonas is of great significance for the healthy development of aquaculture. In this study, we used modern molecular methods to enhance disease control of Aeromonas isolates from freshwater fish in Hebei Province. A total of 130 Aeromonas spp. isolates were isolated from freshwater fish farms in Hengshui, Handan, and Shijiazhuang and all 130 Aeromonas spp. isolates were sequenced for species identification. Of the 130 Aeromonas spp. isolates, 104 isolates were successfully sequenced, and BLAST analysis showed that Aeromonas veronii was predominant in freshwater fish farms in Hebei Province. In addition, 26 antibiotic resistance profiles were obtained from 102 fully cultured isolates among the 104 Aeromonas spp. isolates whose species was primarily identified, and 44 multidrug-resistant bacteria among the 102 isolates were identified using an antibiotic susceptibility test. Using the Multilocus Sequence Typing (MLST) method, 33 out of 44 multidrug-resistant isolates with 14 non-Aeromonas reference strains were selected for phylogenetic and MLST analysis, and all 33 multidrug-resistant isolates were A. veronii. A total of 30 new Sequence Types (STs) were obtained by comparing concatenated sequences (gyrB-groL-gltA-metG-ppsA-recA) on PubMLST website. Furthermore, recombination event analysis detected using RDP5 and ClonalFrameML software 42 and 49 recombination events, respectively, and 22 recombination events were validated by four or more algorithms. Since mutation and recombination events increase clonal diversity and single housekeeping gene sequence alignments are limited for identifying species, we propose the use of multiple concatenated sequence loci to increase discriminatory power. In addition, we propose that the MLST method is an appropriate technique to study and develop the resistance mechanisms of multidrug-resistant Aeromonas and to identify Aeromonas systematically in complex samples obtained from the environment.

Why locking plates for the proximal humerus do not fit well.

INTRODUCTION: We compared the angle of the humerus and plate and to assess compatibility of a plate to the proximal humerus using three-dimensional (3D) printed models. MATERIALS AND METHODS: A total of 120 cases were included, who underwent anteroposterior shoulder radiographs. From these, 30 cases with 3D shoulder computed tomography scans were randomly selected to print 3D model. The lateral angle between the lateral cortex of the humeral shaft and lateral border of the greater tuberosity (GT), neck-shaft angle, and height from the most proximal point of the GT to the angular point were measured. When the plates were applied on the 3D models, the gap from the most proximal point of the GT to the proximal rim of the plate was measured. RESULTS: The mean lateral angle in plain radiographs was 12.9 ± 2.2° and height from the most proximal point of the GT to the angular point was 44.4 ± 4.7 mm. The bending angles of the three plates were 8° and 10°. Height from the proximal rim of the plate to the bending point was 42.4, 42.0 and 43.8 mm. In 98% of cases, the lateral angle of the humerus was larger than all three plates. In 43% of cases, height of the GT was smaller than height of plates. When plates were applied to the 3D model, the mean gap from GT to plate was 4.8 ± 2.8 mm. CONCLUSIONS: There was large variation in the lateral angle of the proximal humerus, which was not correlated with the neck-shaft angle. The lateral angle of the humerus was larger than the plates and prone to varus reduction and medial collapse. LEVEL OF EVIDENCE OR CLINICAL RELEVANCE: Basic science study.

Posterior hemivertebra resection and short segment fusion with pedicle screw fixation for congenital scoliosis in children younger than 10 years: greater than 7-year follow-up.

STUDY DESIGN: A retrospective study. OBJECTIVE: To evaluate the surgical outcomes of posterior hemivertebra resection and short segment fusion with segmental pedicle screw fixation in congenital scoliosis in children younger than 10 years. SUMMARY OF BACKGROUND DATA: This is the first long-term follow-up on surgical outcomes of posterior hemivertebra resection and short segment fusion using segmental pedicle screw fixation in children younger than 10 years with congenital scoliosis. METHODS: Patients with congenital scoliosis (n = 18) younger than 10 years at the time of the surgery were treated by posterior hemivertebra resection and bilateral pedicle screw fixation. The mean age at the time of surgery was 6.6 years (range, 2.6-9.8 yr). They were retrospectively studied with a mean follow-up of 11.4 years (range, 7.1-17.3 yr). RESULTS: The mean Cobb angle of the main curve was 34.4° before surgery, 8.6° after surgery, and 12.9° at last follow-up. In the compensatory cranial curve, the preoperative Cobb angle of 14.5° was corrected to 5.9° postoperatively and was 8.4° at last follow-up. In the compensatory caudal curve, the preoperative Cobb angle of 17.4° improved to 4° postoperatively and 6.6° at last follow-up. There were no crankshaft phenomena and no clinical and radiographical features suggestive of spinal stenosis during follow-up. There were no major vascular or neurological complications related to the pedicle screws. CONCLUSION: Posterior hemivertebra resection after pedicle screw fixation in congenital scoliosis is a safe and effective procedure that can achieve rigid fixation and deformity correction and restore spinal balance. This study showed that early posterior hemivertebra resection of congenital scoliosis before structural changes occur above or below can reduce fusion length, prevent curve progression, and effectively achieve a more satisfactory correction without hazardous iatrogenic spinal stenosis, crankshaft phenomena, or neurological complications. LEVEL OF EVIDENCE: 3.