Volume 86  ·   Issue 09  ·  2006

Bacterial drug resistance and drug-resistant bacterial infection are huge challenges in the field of infection in the 21st century.At present, the main drug-resistant bacteria existing in clinic, such as methicillin-resistant Staphylococcus aureus (MRSA), extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella in Gram-negative bacillus,Enterobacter cloacae resistant to third-generation cephalosporins and multidrug-resistant Pseudomonas aeruginosa,Acinetobacter baumannii and Stenotrophomonas maltophilia, have also increased in recent years.Among them, penicillin-resistant Streptococcus pneumoniae (including PISP and PRSP) reported in many countries around the world also exist and increase year by year in China,especially in children.Many countries also reported that community methicillin-resistant Staphylococcus aureus (CA-MRSA) has become an important pathogen of community infection, and can lead to death in a few severe patients, but there are no relevant reports in China.In addition, multidrug-resistant Mycobacterium tuberculosis is on the rise in AIDS patients or non-AIDS patients.

Lower respiratory tract infection is a common clinical disease and one of the main causes of death. In the clinical diagnosis and treatment of lower respiratory tract infection, the existing laboratory detection technology is difficult to provide reliable etiological data at the first time, so the initial empirical antimicrobial treatment occupies a very important position. Understanding the composition of pathogens and the drug resistance characteristics of common pathogens is the key to rational selection of antimicrobial drugs and ensuring the success of empirical treatment. Therefore, developed countries in Europe and America have invested a lot of manpower and material resources in regular investigation of pathogens of lower respiratory tract infection and drug resistance monitoring of common pathogens, and based on this, they have formulated diagnosis and treatment guidelines suitable for the actual situation in their countries and regions. Learning the research results of these developed countries is undoubtedly of positive significance for improving the clinical diagnosis and treatment level of lower respiratory tract infection in China. However, from some recent investigation results, The drug resistance characteristics and mechanism of common respiratory pathogenic bacteria in China are significantly different from those of European and American countries, so it is not appropriate to completely copy the diagnosis and treatment guidelines of these countries.

minimally invasive surgery (MIS) is an inevitable trend of surgical development. At present, minimally invasive surgery has gradually advanced to computer-assisted minimally invasive technology, which is composed of high and new technologies such as imaging, information science and automatic control technology. Orthopedics is one of the subjects that apply more new technologies and new instruments in the surgical field at present. Therefore, minimally invasive surgery is also the future development direction of orthopedic surgery.

histoplasmosis, leishmaniasis, penicilliosis marneffei, cryptococcosis and toxoplasmosis are rare infectious diseases, which are often manifested as long-term fever, hepatosplenomegaly and cytopenia, and are often misdiagnosed. Most cases are diagnosed by bone marrow puncture to find the corresponding pathogen, and combined with etiological examination.

Acute respiratory infection (ARI) is the most common disease in pediatrics, ranking first in the number of outpatient visits, hospitalizations and deaths, and its mortality rate can reach 20% in some countries and regions [1]. The pathogens of acquired respiratory infection (ARI) include bacteria, viruses, mycoplasma, chlamydia, etc. [1, 2]. Generally speaking, there are more viral pathogens in upper respiratory tract infection, but otitis media and sinusitis can be caused by Haemophilus influenzae (Hi, often non-stereotype, NTHi), Streptococcus pneumoniae (Sp) and Moraxella catarrhalis (Mc), and group A streptococcus (GAS) is often the pathogen of purulent tonsillopharyngitis; Among lower respiratory tract infections, pneumonia is often caused by bacteria, especially severe pneumonia, and bacterial infection is more likely. The common pathogens of community acquired pneumonia (CAP) are Hi (usually type b, Hib), Sp, Mc and Staphylococcus aureus (Sa) [1,2]. The above bacteria can enter the blood stream through the respiratory tract at the same time, causing invasive infections in children, such as sepsis, meningitis, cellulitis, osteoarthritis and soft tissue inflammation.

Modern clinical microbiology is an interdisciplinary subject combining clinical medicine, basic medicine and preventive medicine, and it is also one of the important and mature specialties in laboratory medicine. This emerging subject requires microbiologists and experimental technicians to work jointly, and has four specific tasks: (1) closely combining with clinical practice, discussing, researching and dealing with problems related to infectious diseases with clinicians; (2) Make rapid and accurate test reports on microbial specimens to meet clinical needs in time; (3) Conduct various tests on antibiotics and accept consultations on rational application of antibiotics; (4) Participate in the surveillance, control and management of nosocomial infection [1], which requires clinical microbiologists to complete not only laboratory work, but also related clinical work, and become consultants and consultants for infection control and antibiotic application.

Objective to find out the causes of surgical complications of sphenoid crest meningioma and the methods to reduce surgical complications.Methods 56 cases of sphenoid crest meningioma treated by surgery were retrospectively studied, and the clinical data such as pre-and post-surgical images and surgical videos were analyzed.By MRI examination, 37 cases were medial type, with a diameter of 3.5~7 cm; 5 cases of intermediate type, with a diameter of 3.8~5.2 cm; Among the 56 patients, 19 patients with intermediate and lateral tumors were all resected without surgical complications, 2 patients with medial tumors were injured by unfamiliar facial nerve and excessive pulling of skin flap, 7 cases (5 cases temporarily) were injured by separation and pulling of oculomotor nerve and 1 case of trochlear nerve, 2 cases were injured by premature cutting of tumor-related vessels, 2 cases were injured by excessive separation of lateral fissure, and 1 case was injured by reluctant excision of tumor infiltrating internal carotid artery. Conclusion It is predicted that different patients may have changes in local anatomical relationship and possible difficulties during surgery, and combined with the specific conditions during surgery, good surgical skills can reduce the occurrence of serious complications of medial sphenoid ridge tumor.

Objective to investigate the gene recombination between HLA-B/C loci of human leukocyte antigen complex.Methods Peripheral blood samples were collected from a 39-year-old male and his wife and daughter who were to undergo hematopoietic stem cell transplantation.Firstly, five classical gene loci in HLA-Ⅰ and Ⅱ regions were analyzed by sequential specific primer PCR (PCR-SSP) low and high resolution genotyping and SBT analysis.Then, the genetic family analysis was performed to determine the HLA gene recombination loci. Results The results of HLA high resolution genotyping confirmed that the two haplotypes of the patient (AML-M5) were A*2402101-Cw*030401/0402-B*1301-DRB1*0406-DQB1*030302/0303 and A*02011-Cw*150201/0202-B*4002-DRB1*1405-DQB1*05031, and the two haplotypes of her daughter were A*02011-Cw*150201/0202-B*1301-DRB1*0406-DQB1*030302 That is, the two chromosomes were exchanged, and the recombined haplotype was inherited to the daughter completely. Conclusion A rare family of HLA-B/C gene recombination in Chinese Han population was discovered and proved for the first time in the world, which laid a solid foundation for further research on the mechanism of HLA recombination.

Objective to study the clinical characteristics of polymyositis/dermatomyositis (PM/DM) complicated with emphysema mediastinum, and to explore its risk factors and pathogenic mechanisms. Methods the clinical data of 447 patients with PM/DM were retrospectively analyzed, including age, sex, cutaneous vasculitis, creatine kinase peak, chest imaging changes, complications of emphysema mediastinum, tracheal intubation, treatment process and prognosis. At the same time, 17 cases of DM complicated with emphysema mediastinum reported in the literature were reviewed and analyzed. Results Among 447 patients with PM/DM, 4 cases (0.9%) complicated with emphysema mediastinum were analyzed.<Among the 21 patients, 13 cases (61.9%) had obvious cutaneous vasculitis, while only 44 cases (9.9%) had cutaneous vasculitis among the 443 patients without complication of emphysema. The difference between the two patients was statistically significant (P<0.01). The incidence of pulmonary interstitial lesions in patients with mediastinal emphysema was significantly higher than that in other patients (P<In this group, 3 of 4 patients with emphysema of mediastinum were treated with tracheal intubation, while only 5 (1.1%) of 443 patients without complication of emphysema of mediastinum were treated with tracheal intubation. The difference between the two patients was statistically significant (P<Conclusion Vascular disease may be the direct cause of emphysema mediastinum in DM patients, and young male patients with mild myositis symptoms are prone to emphysema mediastinum. Pulmonary interstitial disease and tracheal intubation may be the risk factors of emphysema mediastinum.

Objective to investigate the inhibition of epidermal growth factor receptor-2 (HER-2) gene expression by RNA interference (RNAi) in ovarian cancer cells and its cellular effects. Methods the experiments were divided into the following three groups: blank control group (untransfected human ovarian cancer SKOV-3 cells), non-specific siRNA transfection group and specific siRNA transfection group. Cisplatin was added 5 days after intervention. The expression of HER-2 mRNA and protein was detected by semi-quantitative PCR (RT-PCR) and Western blot, apoptosis was detected by flow cytometry, and the change of chemical susceptibility to cisplatin was detected by tetramethylazolazole salt (MTT) colorimetric assay, and the change of cell biological characteristics was analyzed. Results HER-2 siRNA significantly inhibited the expression of HER-2 mRNA, and the effect lasted for about 10 days; The expression rate of protein was (25.5±0.8) % in the transfected specific siRNA group, (95.7±0.8) % in the non-specific siRNA group, and (96.6±1.2) % in the blank control group. The difference was statistically significant between the first group and the last two groups (all P<After the intervention, apoptosis increased with the decrease of HER-2 mRNA expression, and the highest apoptosis rate was (53.2 ± 1.0) % on the sixth day, (4.1 ± 0.3) % in the non-specific siRNA transfection group and (4.1 ± 0.3) % in the blank control group. The difference was statistically significant (P<0.001); After intervention, the cell survival rate was (58.4±0.8) % in the group transfected with specific siRNA, (68.0±0.6) % in the group transfected with non-specific siRNA, and (67.0±0.3) % in the blank control group. The difference between the first group and the last two groups was statistically significant (all P<Conclusion siRNA synthesized in vitro can effectively inhibit the expression of HER-2 in SKOV-3 cells, promote cell apoptosis, and increase cell sensitivity to cisplatin. RNAi provides a new strategy for gene therapy of ovarian cancer.

Objective to develop a robot-assisted distal locking nail aiming system for precise positioning in fracture treatment. Methods In the operation of distal locking nail implantation with femoral intramedullary needle, a modular and miniaturized parallel robot structure was designed, and a robot-assisted distal locking nail aiming system with robotic arm spatial positioning technology, binocular vision and 6 degrees of freedom was applied. The distal locking nail implantation was performed by combining C-arm positioning and navigation control. The intramedullary needles were placed into plastic femur (Swiss Sybone, 5 roots, 35 holes), human stem femur specimens (2 roots, 12 holes) and fresh human thigh (1 root, 6 holes) respectively. The size of non-reamed intramedullary needles ranged from 9/310 to 12/340. The distal locking nail implantation with the above intramedullary needles was performed by robot-assisted aiming system. The accurate insertion of the screws was confirmed by C-arm fluoroscopy during the operation, and the X-ray fluoroscopy time of the locking nail implantation was recorded. Results All distal keyholes were successfully locked. Among 53 keyholes, 6 cases (11.1%) of drill bit touched the locking hole, but still passed through the keyhole smoothly, No injury was caused to the intramedullary needle.The intraoperative X-ray fluoroscopy time required during screw implantation was 1.8 s ± 0.3 s. Conclusion Medical robot can only use two computer-calibrated X-ray images, no additional intraoperative X-ray fluoroscopy is needed to navigate the instrument, and the total X-ray transmission time during operation is significantly reduced. The human-computer interaction function is easy to master, and can be used as a technical platform for accurate positioning and stable operation in robot-assisted long bone treatment.

Objective to investigate the feasibility of computer-aided robotic arm navigation and positioning method in trauma orthopedic surgery. Methods Three-dimensional coordinate values of 307 groups of targets (24 model bone surgery, 21 cadaver bone surgery and 40 clinical surgery) were randomly selected and implemented by computer-aided trauma orthopedic surgery planning system software (CAOTS). Monte Carlo method was introduced to calculate the error, and SPSS 2.0 statistical software was used to analyze the variance of the measurement results. Results The computer-aided robotic arm navigation and positioning method was accurate and reliable, and the spatial standard deviation σ of the target was 0.1568 ± 0.0696. The effective accuracy range of three-dimensional coordinates of the target was ±0.6792, that is, the positioning accuracy was 0.0408 mm ± 0.4578 mm. Conclusion CAOTS can accurately locate in trauma orthopedic surgery. Through relevant human-computer interaction software and positioning surgical instruments, clinicians can easily master CAOTS, which significantly improves the accuracy and safety of positioning operation during surgery.

Objective to investigate the expression and transmission characteristics of ermB gene in macrolide-resistant Streptococcus pneumoniae in Shanghai. Methods A total of 86 strains of Streptococcus pneumoniae resistant to erythromycin in Shanghai were collected, and their susceptibility to 12 antibiotics was detected by E test and K-B disk diffusion method; Determination of macrolide resistance phenotype by double-disc method (D test); The regulatory sequences of ermB gene in the drug resistance genes ermB, mefE and Tn1545 and Tn917 were detected by PCR amplification. The polymorphism of the regulatory sequences was analyzed by sequencing and BLAST alignment, and the strains were divided into Tn1545 group and Tn917 group according to the difference of Tn1545 and Tn917 carried by the strains, and the difference of drug resistance phenotype mediated by the two strains was analyzed. The genetic backgrounds of different strains were analyzed by BOX-PCR. Results (1) The detection rates of ermB, mefE, Tn1545 and Tn917 in 86 strains of erythromycin-resistant Streptococcus pneumoniae were 94%, 46%, 87% and 7%, respectively. The 5 strains with ermB-mefE + genotype did not detect Tn1545 and Tn917. (2) The Sp in Tn1545 and Tn917 groups were highly resistant to erythromycin (the lowest inhibitory concentration MIC50 was 256 μ g/ml). The MIC of Tn917 group to β-lactam antibiotics was lower than that of Tn1545 group, and the resistance rates to tetracycline, compound sulfa and levofloxacin were also lower than that of Tn1545 group. (3) The deletion of 194 bp fragment in the promoter region of ermB gene and the insertion of TAAA at the N-terminal of the leader peptide in three strains of Tn917 group may lead to the transformation of ermB gene from inducible to constitutive expression; The phenotype of Tn1545 group was mainly cMLSB. (4) BOX-PCR patterns were sporadic, and no single drug-resistant clone was found. Conclusion the macrolide-resistant Streptococcus pneumoniae in Shanghai is mainly mediated by ermB gene, which is mostly carried by Tn1545 and transmitted horizontally.

Objective to investigate the effect of attenuator gene mutation on cephalosporinase (AmpC) gene expression and drug resistance phenotype in a clinical isolated strain of Escherichia coli. Methods the phenotype of a clinical isolated strain of Escherichia coli was detected by three-dimensional assay, isoelectric focusing, enzyme inhibition assay and microdilution method. The regulatory gene was amplified and analyzed by polymerase chain reaction (PCR), gene sequencing and alignment. The regulatory gene was cloned into pCAT3-basic (reporter vector without promoter), and the gene expression was studied by enzyme-linked immunoassay (direct assay) and minimum inhibitory concentration (indirect assay). Results Compared with the standard strain of Escherichia coli K-12 AmpC gene, the attenuator region of the tested strain showed 4 bases 22C-T, 26, 27TA-GT and 32G-A substitution. The three-dimensional assay was positive, isoelectric focusing and enzyme inhibition assay showed that the strain could produce 3 kinds of β-lactamases with isoelectric points (PI) of 5.4, 8.2 and 9.0, respectively. The β-lactamase with isoelectric point of 9.0 could be inhibited by cloxacillin but not by clavulanic acid. The microdilution method showed that the strain was resistant not only to various third-generation cephalosporins, but also to cefepime, but it was still sensitive to carbapenem antibiotics. Its AmpC regulatory gene was successfully cloned into the reporter gene vector pCAT3-basic, and direct and indirect detection showed that the mutated regulatory gene expressed CAT protein at a level about 10 times higher than that of the sensitive strain. Conclusion The mutation of attenuator of Escherichia coli can lead to high expression of AmpC gene and show resistance to various β-lactam antibiotics.

Objective to determine the new aminoglycoside resistance genes and their transmission mechanisms in gentamicin high-level resistant enterococcus (HLGR). Methods HLGR was screened by agar screening method, and the drug susceptibility test was carried out by agar dilution method and K-B paper method. The drug resistance genes and their transmission mechanism were studied by polymerase chain reaction (PCR), plasmid extraction, Southern hybridization, enzyme digestion and cloning sequencing. Results Enterococcus could induce HLGR by producing a new plasmid-mediated aminoglycoside resistance gene APH (2 ") -Ie encoding enzyme APH (2") -Ie. Enzyme digestion and sequencing showed that APH (2 ") -Ie had high amino acid homology with chromosome-mediated APH (2") -Id, and there was an insertion sequence encoding the transposase TnpA in the upstream and a gene encoding the streptomycin adenosyltransferase (str) in the downstream. Southern hybridization confirmed that the resistance gene was located on the plasmid about 16 kb. Conclusion HLGR can be induced by a new plasmid-mediated aminoglycoside modifier APH (2 ") -Ie, and it can be transmitted between plasmids or chromosomes through transposase and other drug resistance genes.

Objective to investigate the prevalence of colistin-only susceptible Acinetobacter baumannii (COS-AB) in multidrug-resistant Acinetobacter baumannii (MDR-AB) from the genetic level, and to provide experimental data for controlling its epidemic outbreak. Methods The clinical data of 136 patients with COS-AB clinical infection from June 2004 to May 2005 in Shanghai Ruijin Hospital were collected and analyzed. At the same time, 66 strains of Acinetobacter baumannii isolated from May 2004 to December 2004 were collected, including 33 strains of COS-AB and 33 strains of non-colistin-sensitive Acinetobacter baumannii (non-COS-AB). The prevalence of COS-AB was analyzed by molecular epidemiology and statistical methods such as random primer PCR (RAPD) and pulsed field gel electrophoresis (PFGE). The results confirmed that the outbreak of COS-AB occurred from June 2004 to May 2005. The RAPD (primers ERIC2 and 272) classified as one type, while the PFGE classified as two types. Conclusion COS-AB cross-infection is serious, so strict disinfection and isolation measures should be taken, and the prevalence of COS-AB in the environment and in patients should be monitored closely. PFGE is more accurate to type Acinetobacter baumannii.

Quinolones are widely used in the treatment of urinary tract infections, respiratory tract infections, abdominal infections, etc. However, with the increase of clinical application, bacterial resistance to quinolones is increasing rapidly. It has been found that the main mechanisms of bacterial resistance to quinolones are target change and active efflux, both of which are chromosome-mediated. In recent years, a completely different plasmid-mediated resistance mechanism has been found from the former two, and it has been confirmed in more and more clinical strains.

extended-spectrum β-lactamases (ESBL) were first discovered in Germany in 1983. In just over 20 years since then, ESBL-producing bacteria have become a worldwide epidemic, especially in nosocomial infections caused by Gram-negative bacteria. ESBL is a class of β-lactamases that can hydrolyze oxyimino β-lactam antibiotics mediated by plasmid and can be inhibited by β-lactamase inhibitors (such as clavulanic acid). So far, more than 200 ESBL have been discovered worldwide. According to the homology of encoding genes, ESBL can be divided into 5 types: TEM, SHV, CTX-M, OXA and other types, including 80 TEM, 48 SHV, 43 CTX-M, 18 OXA and nearly 20 other genotypes (WWW.Lahey.org/studies/). The detection rate, drug resistance and genotype of ESBL-producing bacteria are different in different countries, regions and hospitals because of the different antibacterial drugs used.

temporal lobe epilepsy (TLE) is the most common type of refractory epilepsy. There have been many studies on the diagnosis and treatment of one-sided TLE by domestic and foreign scholars, but there are few reports on bilateral temporal lobe epilepsy (BTLE). We retrospectively summarized 8 cases of TLE admitted to the Department of Neurology of Tianjin Medical University General Hospital from September 2003 to July 2005. Magnetoencephalogram (MEG) examination confirmed that they were bilateral temporal lobe-induced epilepsy, and verified by intraoperative cortical electroencephalogram (ECoG) and/or deep electroencephalogram (DEEG) examination, and achieved satisfactory results after operation.

streptococcus pneumoniae (SP) is the main pathogen of community acquired pneumonia (CAP) in children of all ages. In order to understand its drug resistance and guide the rational use of antibiotics in clinic, the Children's Hospital affiliated to Shanghai Jiaotong University monitored the susceptibility of 10 commonly used antibiotics in SP isolated from nasopharynx of children with CAP for three consecutive years from 2000 to 2002.

A 17-year-old female was admitted to the hospital for fever with lower back pain for 1 1/2 months. The patient developed lower back pain without obvious trigger at night 1 1 1/2 months ago, with severe lumbosacral area and no radiation to lower limbs, accompanied by low fever, with a maximum of 37.5℃, night sweat, and general discomfort, which relieved spontaneously after about 1 h. There was no heel pain, morning stiffness, or rash. Similar attacks occurred every day at night after that, and the pain worsened 1 month ago, with a peak body temperature of 38~38.7℃. Physical examination: bilateral sacroiliac joint tenderness, bilateral 4-word test (+). The erythrocyte sedimentation rate (ESR) (66 mm/h), rheumatoid factor (RF) (-), alleleukocyte B27 antigen (HLA-B27) (-) were checked. Sacroiliac joint CT (Figure 1) showed that the bilateral sacroiliac joint space was slightly narrowed and the articular surface was blurred. Considering "early ankylosing spondylitis", she was given prednisone 5 mg twice/d, methotrexate 10 mg once/week, and loxoprofen sodium 60 mg three times/d. The pain was relieved, but the attacks were still intermittent.There was no similar family history.