Bacteriophages are abundantly distributed viruses , which are able to infect bacteria .Bacteriophages are becoming a focus of attention for microbiologists , as they can cause pollution to the fermentation industry and might serve as alternative therapies for antibiotic-resistant pathogenic bacteria .Effective bacteriophage infection normally involves adsorp-tion, injection, replication, assembly and release , against which bacteria have developed various resistance strategies .The research progress in the bacteriophage resistance mechanisms is briefly reviewed in this paper .

Objective To investigate the different operative style for the intraspinal extramedullary neoplasms in the cervical vertebrae as well as evaluate the clinical effect of titanium net for spinal canal reconstruction and bone autograft after laminectomy. Methods Since March 2002 to September 2008, 26patents (14 men, 12 women) with the intraspinal extramedullary neoplasm in the cervical vertebrae. The average age was 38 years (range, 6-76 yr). According to Frankel classification, there were 26 cases for grade B before operation, 8 cases for grade C, 11 for grade D, and 4 for grade E. All patients underwent hemilaminectomy (as group HL) or total laminectomy combined with spinal canal reconstruction with titanium net (as group TL). Recovery of nerve function and bone fusion were recorded. Preoperative and postoperative cervical curvature index and ranges of neck motion were recorded and compared. Results Among the 3cases with incomplete paraplegia, neurological status ameliorated from Frankel grade B to C; 8 cases of Frankel grade C recovered to grade D; 11 cases of Frankel grade D improved to grade E in 10 cases and 1to grade D. Bone fusion was formed on the titanium net and spinal stability was well after operation. Loss of cervical curvature indices was 2.2±2.3 in group HL and 4.3±2.5 in group of TL, and the difference was of statistically significant (t=2.05,P＜0.05). At the same time, loss of ranges of neck motion was 1.3°±1.2°ingroup of HL and 9.2°±4.1°in group TL, significant difference was also seen (t=1.71 ,P＜ 0.05). Conclusion Hemi-laminectomy approach to intradural lesions lends itself well to eccentric tumors with smaller size. For the cases of total laminectomy, it is necessary and reliable to reconstitute integrity of spinal canal with titanium net and bone autograft.

Objective To report a method of handling dural injury with cerebrospinal fluid leakage during the spinal operation process and analyze its effect,to comparatively analyze with the existing methods and to find a better way processing this problem.Methods A total of 36 patients with dural injury and cerebrospinal fluid leakage during the spinal operation process were collected.Among these clinical cases,there were 15 males,21 females,age ranged from 26 to 78 years old,average 58 years old.During the spinal operation process,the injured dura was sutured or repaired.After that,the dural wound was glued with a piece of muscle or fascia by a kind of medical glue named KangPaiTe.After the operation,broad -spectrum antibiotics and timely fresh dressing changing for the wound were applied.The nature and volume of the drainage fluid was documented and analyzed.When the volume of the drainage fluid was below 50mL per day,the drainage tube was pulled away,and the incision of the drainage tube was sutured again.Results The cerebrospinal fluid leakage lasted from 0 day to 4 days,average 1.5 days;the drainage tube was placed from 1 day to 5 days,average 2 days;no wound infection and other complications occurred among all the clini-cal cases included in this study.Conclusion After the injured dura was sutured or repaired,gluing the dural wound with a slice of muscle or fascia by a kind of medical glue named Kangpaite is a better method of handling dural injury with cerebrospinal fluid leakage.

The process of intervertebral disc degeneration,which could result in intervertebral disc structural and functional change,is a chronic one with multiple factors.The pathophysiologic process is still not completely find out.More and more research reports manifest that certain gene polymorphism also lead to increased risk of intervertebral disc degeneration except environmental factors.Discussions about related genetic factors and their pathophysiological role in the process of degeneration could have a further understanding to disease development.Elucidating genetic components which are associated with degeneration could not only provide insights into the mechanism of the process,but also have clinical significance for early diagnosis and prevention.In order to have a thorough understanding of functional role played by different genes,this paper summarize polymorphism and disease correlation by selecting 15 genes after reviewed the related literature published in recent years.Genetic polymorphisms in 15 genes have been analyzed in association with intervertebral disc degeneration,including aggrecan,collagen Types Ⅰ,Ⅸ and Ⅺ,fibronectin,HAPLN 1,CILP,MMP-1,2 and 3,PARK2,IL-1,6 and VDR.Each genetic polymorphism codes for a protein which has a functional role in the pathogenesis of disease.Among the 15 genes analyzed,polymorphisms in aggrecan,Type Ⅸ collagen,MMP3,IL1,IL6 and VDR show the most promise as functional variants.Genetic studies are necessary for understanding the mechanism of the degeneration.Relevant genetic information could be used as a predictive model for determining individuals' risk for intervertebral disc degeneration eventually.

To enhance the quality and efficiency of ozagrel by investigating the differences between the ozagrel polymorphs in bioavailability. Solid ozagrel in different polymorph forms were orally administered to SD rats. An HPLC method was established to determinate plasma level of ozagrel. The bioavailabilities of two polymorph forms were calculated and compared. The pharmacokinetic parameters of ozagrel, were as follows: Cmax was 32.72 ± 17.04 and 34.01 ± 19.13 mg · L(-1), respectively; AUC0-t was 61.14 ± 14.76 and 85.56 ± 18.08 mg · L(-1) · h, respectively; t½ was 1.53 ± 0.51 and 4.73 ± 3.00 h, respectively. There was no significant difference in pharmacokinetic parameters between form I and II polymorphs of ozagrel while the t½ of form II is longer, which indicates that the use of form II polymorph as pharmaceutical product may prolong the effective action time in clinics. This would help the polymorph quality control in drug production.

Objective To construct a technical platform for scarless gene modification of Yersinia pestis and to study the functions of its specific genes.Methods The resistance fragment, including upstream and downstream homologous arms of targeted regions, was reamplified by asymmetric PCR.The amplicons were introduced into Y.pestis harboring plasmid pKD46.With the induction of L-arabinose,the recombinant related enzymes: Exo, Beta and Gam, were expressed to guide the homologous recombination.A donor plasmid, pKSI-1, which carried the desired modification fragment flanking by I-SceⅠ recognition sites, was introduced into Y.pestis as the second step of λ-Red recombination with the help of pREDTKI.Results and Conclusion Two mutant strains:△waaA and waaA(△9nt), were successfully constructed for Y.pestis strain 201.Scarless modification introduces no extra modification to the genome, and it is ideal for comprehensive functional genomic studies.

Objective Using single direction dispersion breathless DWI, to analyze the value of DWI for vertebral bone marrow infiltration in patients with acute leukemia (AL). MethodsForty-two patients with AL and 15 healthy volunteers received vertebral sagittal DWI with single shot spin-echo echoplan imaging (SS-SE-EPI) sequence( b value ＝ 0,650 s/mm2) at a GE Signa Excite 1. 5 T scanner with 8 channels body coil. DWI for all patients were performed from three directions, including from superior to inferior (S/I), from anterior to posterior (A/P) and from right to left (R/L). The apparent diffusion coefficient (ADC) value was measured on ADC map from each direction using GE-Function tool DWI software. Forty two patients consisted of 13 onset with untreated patients and 29 treated patients (7 nonremission,8 complete remission and 14 consolidation therapy). The ADC values among the three diffusion directions were compared. Analysis of variance and t test were used to compare the ADC values in different AL stages, Pearson correlation analysis was used to analyze the correlation between ADC values and the percentage of bone marrow progenitor cells. Results The ADC values from S/I, A/P and R/L of 362 vertebras in the 57 subjects are (0. 758 ±0. 009) × 10-3 mm2/s, (0. 732 ±0. 009) × 10 -3 mm2/s and (0. 758 ±0. 009) × 10 -3 mm2/s, respectively. There is no statistical significance( F ＝ 2. 958, P ＞ 0. 05 ).The ADC values from S/I of 94 vertebras in 15 healthy volunteers is (0. 697 ± 0. 122) × 10 -3 mm2/s, of 85 vertebras in 13 untreated AL patients is (0. 592 ±0. 071 ) × 10-3mm2/s. There is statistical significance between them ( t ＝ 2. 568, P ＜ 0. 05 ) ; The ADC value of 183 vertebras in 29 treated AL patients [ ( 0. 796 ±0. 225 ) × 10-3mm2/s]is higher than that in untreated patients with statistical significance (t ＝ -1. 332,P ＜0. 05). One hundred and forty vertebras in patients with complete remission and consolidation therapy were [ (0. 786 ±0. 184) × 10-3 mm2/s],and 43 vertebras in patients with non-remission(NR) [ (0. 804 ±0. 327 ) × 10 - 3 mm2/s], there was not statistical significance between them ( t ＝ - 0. 160, P ＞ 0. 05 ). The ADC values from S/I direction of untreated patients showed significant negative correlation with the proportion of the blast cell in the bone marrow ( median value 26. 4％. Min 7.9％, Max 48. 2％ ) ( r ＝- 0. 524, P ＜ 0. 05 ). ConclusionsDWI of vertebral bone marrow is isotropy. ADC value is a non-invasive and quantitative index for evaluating the pathogenetic condition of AL.

ObjectiveUsing dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to evaluate the hemodynamic perfusion characteristics of bone marrow infiltration in patients with acute leukemia (AL). MethodsForty-seven patients with AL received coronal pelvic T1WI DCE-MRI with fast low angle shot (FLASH) sequence. Among them, 25 were initial onset untreated (IOU) patients, 22 were treated AL patients, including 14 with complete remission (CR) and 8 with non-remission ( NR). The hemodynamic perfusion parameters including maximum percentage of enhancement ( Emax ) and slope were determined based on enhancement-time curves ( ETCs ) of iliac and lumbar vertebra. The proportion of marrow myeloblasts was recorded.For all patients, quantitative perfusion parameters of bone marrow infiltration in ilium were compared with those in lumbar. The values of Emax and ES were compared among IOU,CR and NR patients.Correlations between perfusion parameters and histopathological results were assessed. ResultsIn all the 47 patients, the Emax values of bilateral iliac bone marrow ( 15.70 ± 7.06)were slightly higher than that of lumbar bone marrow ( 11. 28 ± 5.52 ), and the difference was statistically significant (P ＜0. 01 ).There was no significant difference in the slop value between bilateral iliac bone marrow (0. 82 ± 0. 12 ) and lumbar bone marrow (0. 80 ± 0. 09 ) ( P ＞ 0. 05 ). In the 25 untreated patients,the Emax and slop values were 17. 15 ± 5.75 and 0. 98 ± 0. 13, respectively; in the 14 CR patients, they were 8. 76 ±3.93 and 0. 26 ± 0. 04, respectively, and in the 8 NR patients, they were 21.62 ± 6. 50 and 1. 38 ± 0. 02, respectively. There was significant difference in the Emax and slop values among the three groups (P＜0. 05).Compared with IOU and NR patients, both the Emax and slop values decreased significantly in iliac bone marrow of AL patients with CR (P ＜ 0. 05 ). There was no significant difference between IOU and NR patients ( P ＞ 0. 05 ). A significant positive correlation was found between Emax value of iliac bone marrow and the proportion of marrow myeloblasts ( r ＝0. 501 ,P ＜0. 05 ). There was a negative correlation between slop value of iliac bone marrow and the proportion of marrow myeloblasts ( r ＝0. 235 ,P ＞0.05).ConclusionsDCE-MRI can beused for evaluating the hemedynamic characteristics of microcirculation of bone marrow infiltration in patients with AL, which can provide useful information in evaluating prognosis and monitoring therapeutic effect.

Objective To evaluate the clinical results of the Ilizarov technique for the treatment of the complex rigid talipes equinovarus deformities.Methods From July 2005 to July 2011,28 patients (41 feet) with rigid talipes equinovarus deformities which had been corrected with the Ilizarov technique were retrospectively analyzed,including 18 males (26 feet) and 10 females (15 feet) with an average age of 15.3 years.According to the classification system proposed by Diméglio,31 feet were categorized as grade Ⅲ,and 10 as grade Ⅳ.We performed corrections with a soft tissue release in 23 feet,and with a limited osteotomy in 18,and then a Ilizarov external fixator was applied.Anteroposterior and lateral X-rays were taken to compare the pre and postoperative data in terms of the angle of plantarflexion and dorsiflexion,the range of motion of the ankle joint,radiological measurements of the talocalcaneal angle.Results All the 28 patients achieved an outpatient follow-up,with an average of 25 months.All patients achieved a plantigrade foot with an almost normal appearance as the fixator was removed after applied for an average of 5.1 months (range,2-14).At the preoperative and final follow-up respectively,the angle of dorsiflexion of the foot was -45.0°±12.0° and 9.5°±5.5°,the angle of plantarflexion was 67.0°±14.0° and 45.5°±7.8°,talocalcaneal angle was 6.5°±4.5° and 22.5°±5.5° in anteroposterior radiograph and 5.5°±11.0° and 40.6°±8.5° in lateral radiograph.Spastic ischemia occurred in one foot and relieved by a slower distraction rate.Wire-hole infections occurred in 5 feet and treated by dressing changs,wire tract altering and antibiotic therapy,finally the infections were controlled.Deformity relapsed in one foot three months after the device was removed,then corrected with an additional fixator application and has not recurred till the final follow-up.Toe contracture and residual deformity occurred in 5 feet and 3 feet,respectively.Conclusion The Ilizarov technique is an effective method for correction of complex rigid talipes equinovarus deformities,with which the appearance and function of the foot could be kept as much as possible,and without impact on food development.

Objective:To explore different surgical treatment options and effect for intraspinal cement leakage after percutaneous vertebroplasty (PVP).Methods:A retrospective case series study was carried out to analyze the clinical data of 5 patients with intraspinal cement leakage after PVP for osteoporotic vertebral compression fracture (OVCF) admitted to People's Hospital of Shanxi between May 2016 and January 2020, including 1 male and 4 females, with the age of 65-82 years [(75.4±7.5)years]. Injured segments were located at T 12-L 1 in 1 patient, L 1 in 1, L 2-4 in 1, L 3 in 1 and L 4-5 in 1. The American Spinal Injury Association (ASIA) classification was grade C in 2 patients and grade D in 3. Muscle strength was grade II in 2 patients and grade III in 3. The leakage of bone cement in the spinal canal was strip or columnar in 3 patients, leaning to one side of the spinal canal and adjacent to the nerve root, and the bone cement was removed by transforaminal endoscope for decompression. The leakage of bone cement in the dura mater and spinal canal was found in 2 patients. The intradural bone cement leakage was removed by durotomy, and the bone cement in the spinal canal was removed by transpedicular osteotomy, bone graft fusion and internal fixation. The visual analogue scale (VAS), Oswestry dysfunction index (ODI), ASIA grade and muscle strength were observed before operation, at 3 days, 3 months after operation and at the last follow-up. Results:All patients were followed up for 12-16 months [(13.6±1.8)months]. The VAS was significantly decreased at postoperative 3 days, 3 months and at the last follow-up [(2.6±0.6)points, (2.1±0.3)points, (1.9±0.5)points] when compared to (7.1±1.5)points before operation ( P<0.01). However, the VAS had no statistical difference at different time points after operation ( P>0.05). The ODI was 42.4±10.2, 25.6±6.0 and 21.4±3.6 at postoperative 3 days, 3 months and at the last follow-up, significantly different from that before operation (74.2±7.3) ( P<0.05 or 0.01). However, the ODI had no statistical difference at postoperative 3 months and at the last follow-up ( P>0.05). Two patients with preoperative ASIA grade C recovered to grade D and 3 patients with preoperative grade D recovered to grade E at the last follow-up ( P<0.05). Two patients could walk without crutches with muscle strength improved from grade II preoperatively to grade IV at the last follow-up ( P<0.01). Three patients had completed recovery of neurological function with muscle strength improved from grade III preoperatively to grade V at the last follow-up ( P<0.01). Conclusions:For OVCF patients with intraspinal canal cement leakage and neurological symptoms after PVP, if the bone cement is located on one side of the spinal canal and adjacent to the nerve root, the bone cement should be removed by foraminal endoscope for decompression; if the cement leakage occurs in the dura mater, the dura mater should be cut to remove the bone cement for decompression, which can effectively relieve pain and promote functional recovery.