Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become a widely used method in the field of microbial identification. Its obvious advantages including rapidity, great accuracy and high throughput attract many researchers to investigate its potential for usage in other microbiological fields. Currently, several studies have reported MALDI-TOF MS-based analysis of bacterial resistance to antibiotics, which can identify the specific heterogeneous spectrum peaks related to drug resistance through simple visual analysis of the spectrum or more complex analysis of the entire spectrum using informatics methods and statistical approaches. Therefore, MALDI-TOF MS has become a potential tool for detecting antibiotic resistance in bacteria. This review mainly summarized the progress in MALDI-TOF MS-based analysis of bacterial resistance to antibiotics.

Objective To evaluate the therapeutic effect of recombinant human granulocyte-macrophage colony stimulating factor ( rhGM-CSF) combined with sulfadiazine silver ( SD-Ag) unguent on deep second degree burn. Methods Eighty-nine patients with deep second-degree burn (burns areas<10%) were enrolled.These patients were divided into two groups at random (Group A and Group B).The patients in Group A were treated with SD-Ag unguent only, and those in Group B were treated with rhGM-CSF and SD-Ag unguent.The therapeutic effects and the adverse drug reaction were recorded. Results The healing time in Group A [(19.79±1.47) days] was obviously shorter than that in Group B [(15.76±1.63) days].The total wound healing rates in Group B [on day 9:(76.41±3.24)%, day 13:(95.01±1.43)%, day 16:(99.54±0.88)%, and day 21 (100.00±0.00)%] were higher than those of Group A [on day 9: (67.24±2.33)%, day 13: (75.54±1.11)%, day 16:(88.33±1.32)%, day 21:(99.14±1.95)%].During the treatment, there was no obvious adverse reaction was observed in the two groups. Conclusion The application of rhGM-CSF combined with SD-Ag unguent can not only accelerate the healing rates of deep second-degree burn, but also has curative effect with safety.

Objective To investigate the feasibility of a new polyclonal antibody specific to fetal hemoglobin (HbF) and its application in enrichment of circulating fetal nucleated red blood cell(NRBC) for non-invasive prenatal diagnosis. Methods A polyclonal antibody against a synthetic peptide comprising residues 69-78 of the γ-chain of HbF was prepared and conjugated to carrier protein KLH as the immunogen according to the specific antigenic determinant. The peptide-KLH solution was mixed with freund's complete or incomplete adjuvant and immunized goat to prepare specific polyclonal antibody against the γ-chain of fetal hemoglobin. After purification with protein G, maternal blood was obtained from 32 pregnant women at 22 to 39 weeks of gestation. NRBCs were separated and then stained with antibody against the γ chain of HbF. All the positive cells were collected by micromanipulator under microscopic observation, and whole genome was amplified by improved primer extension preamplification (PEP). Multiplex polymerase chain reaction amplification at nine different polymorphic short tandem repeat (STR) loci was also used to determine origin of the positive cells isolated from maternal blood. Results NRBCs stained with antibody against the γ chain of HbF were found in all of the blood from the 32 cases. Attached positive cells with anti-HbF staining have unique morphological characteristics, low nucleus-to-cytoplasm ratio, brown cytoplasm and blue dense nucleus after hematoxylin counterstain under microscopic observation, which can distinguished NRBCs with other cells. A total of 183 NRBCs were found in all of 32 pregnant women at a range of 0.6～1.8 cell/ml venous blood. The accurate rate was 90.6% by the STR genotype identification. Conclusion The antibodies specific to fetal γ-chain of fetal hemoglobin with synthetic peptide technology may have wide clinical utility in identification of fetal NRBCs from maternal circulation for non-invasive prenatal genetic diagnosis.