Effectiveness of preoperative decolonization with nasal povidone iodine in Chinese patients undergoing elective orthopedic surgery: a prospective cross-sectional study

Staphylococcus aureus colonization in the nares of patients undergoing elective orthopedic surgery increases the potential risk of surgical site infections. Methicillin-resistant S. aureus (MRSA) has gained recognition as a pathogen that is no longer only just a hospital-acquired pathogen. Patients positive for MRSA are associated with higher rates of morbidity and mortality following infection. MRSA is commonly found in the nares, and methicillin-sensitive S. aureus (MSSA) is even more prevalent. Recently, studies have determined that screening for this pathogen prior to surgery and diminishing staphylococcal infections at the surgical site will dramatically reduce surgical site infections. A nasal mupirocin treatment is shown to significantly reduce the colonization of the pathogen. However, this treatment is expensive and is currently not available in China. Thus, in this study, we first sought to determine the prevalence of MSSA/MSRA in patients undergoing elective orthopedic surgery in northern China, and then, we treated the positive patients with a nasal povidone-iodine swab. Here, we demonstrate a successful reduction in the colonization of S. aureus. We propose that this treatment could serve as a cost-effective means of eradicating this pathogen in patients undergoing elective orthopedic surgery, which might reduce the rate of surgical site infections.

Effectiveness of preoperative decolonization with nasal povidone iodine in Chinese patients undergoing elective orthopedic surgery: a prospective cross-sectional study.

Staphylococcus aureus colonization in the nares of patients undergoing elective orthopedic surgery increases the potential risk of surgical site infections. Methicillin-resistant S. aureus (MRSA) has gained recognition as a pathogen that is no longer only just a hospital-acquired pathogen. Patients positive for MRSA are associated with higher rates of morbidity and mortality following infection. MRSA is commonly found in the nares, and methicillin-sensitive S. aureus (MSSA) is even more prevalent. Recently, studies have determined that screening for this pathogen prior to surgery and diminishing staphylococcal infections at the surgical site will dramatically reduce surgical site infections. A nasal mupirocin treatment is shown to significantly reduce the colonization of the pathogen. However, this treatment is expensive and is currently not available in China. Thus, in this study, we first sought to determine the prevalence of MSSA/MSRA in patients undergoing elective orthopedic surgery in northern China, and then, we treated the positive patients with a nasal povidone-iodine swab. Here, we demonstrate a successful reduction in the colonization of S. aureus. We propose that this treatment could serve as a cost-effective means of eradicating this pathogen in patients undergoing elective orthopedic surgery, which might reduce the rate of surgical site infections.

Exploring laccase genes from plant pathogen genomes: a bioinformatic approach.

To date, research on laccases has mostly been focused on plant and fungal laccases and their current use in biotechnological applications. In contrast, little is known about laccases from plant pathogens, although recent rapid progress in whole genome sequencing of an increasing number of organisms has facilitated their identification and ascertainment of their origins. In this study, a comparative analysis was performed to elucidate the distribution of laccases among bacteria, fungi, and oomycetes, and, through comparison of their amino acids, to determine the relationships between them. We retrieved the laccase genes for the 20 publicly available plant pathogen genomes. From these, 125 laccase genes were identified in total, including seven in bacterial genomes, 101 in fungal genomes, and 17 in oomycete genomes. Most of the predicted protein models of these genes shared typical fungal laccase characteristics, possessing four conserved domains with one cysteine and ten histidine residues at these domains. Phylogenetic analysis illustrated that laccases from bacteria and oomycetes were grouped into two distinct clades, whereas fungal laccases clustered in three main clades. These results provide the theoretical groundwork regarding the role of laccases in plant pathogens and might be used to guide future research into these enzymes.

Characterization of FeDREB1 promoter involved in cold- and drought-inducible expression from common buckwheat (Fagopyrum esculentum).

C-repeat-binding factor (CBF)/dehydration-responsive element (DREB) transcription factors play key roles in plant stress responses. However, little information is available on the regulation of CBF/DREB expression. In this study, we isolated and characterized the FeDREB1 promoter sequence from the common buckwheat accession Xinong 9976. To identify the upstream region of the FeDREB1 gene required for promoter activity, we constructed a series of FeDREB1 promoter deletion derivatives. Each deletion construct was analyzed through Agrobacterium-mediated transient transformation in tobacco leaves treated with 4°C cold or drought stress. Promoter-beta-glucuronidase fusion assays revealed that the pCD1 (-270 bp) deletion in the upstream region of FeDREB1 could activate expression of the GUS gene at 4°C. The pCD1 (-270 bp), pCD2 (-530 bp), and pCD3 (-904 bp) deletion induced low-level GUS expression under drought stress. However, the pCD4 (-1278 bp) deletion clearly activated GUS gene expression. Our results suggest that sections pCD1 (-270 bp) and pCD4 (-1278 bp) in the FeDREB1 gene promoter are new sources of induced promoters for adversity-resistance breeding in plant genetic engineering.

Molecular characterization and functional analysis of the Nep1-like protein-encoding gene from Phytophthora capsici.

Phytophthora capsici is an aggressive plant pathogen that affects solanaceous and cucurbitaceous hosts. Nep1-like proteins (NLPs) are a group of effectors found particularly in oomycetes and considered important virulence factors. We identified an NLP gene (phcnlp1) from the highly virulent P. capsici strain Phyc12 that had an encoded polypeptide of 476-amino acid residues and a predicted molecular mass of 51.75 kDa. We performed quantitative reverse transcription-polymerase chain reaction to detect the expression pattern of phcnlp1 during various phases of interaction with the host plant, and the results showed that phcnlp1 was increasingly expressed during symptom development after P. capsici infection of pepper leaves. We also confirmed that phcnlp1 caused significant necrosis on tobacco plants when expressed based on potato virus agroinfection. All results indicated that phcnlp1 belongs to the NLP gene family and is important for the pathogenesis of P. capsici in its hosts.

Identification of 18 genes encoding necrosis-inducing proteins from the plant pathogen Phytophthora capsici (Pythiaceae: Oomycetes).

Phytophthora capsici is an aggressive plant pathogen that affects solanaceous and cucurbitaceous hosts. Necrosis-inducing Phytophthora proteins (NPPs) are a group of secreted toxins found particularly in oomycetes. Several NPPs from Phytophthora species trigger plant cell death and activate host defense gene expression. We isolated 18 P. capsici NPP genes, of which 12 were active during hypha growth from a Phytophthora stain isolated from pepper (Capsicum annuum) plants in China. The 18 predicted proteins had a sequence homology of 46.26%. The 18 Pcnpp sequences had a conserved GHRHDWE motif and fell into two groups. Eleven sequences in group 1 had two conserved cysteine residues, whereas the other seven sequences in group 2 lacked these two cysteine residues. A phylogenetic tree was constructed on the basis of the alignment of the predicted protein sequences of 52 selected NPP genes from oomycetes, fungi and bacteria from Genbank. The tree did not rigorously follow the taxonomic classification of the species; all the NPPs from oomycetes formed their own clusters, while fungal sequences were grouped into two separate clades, indicating that based on NPPs, we can separate oomycetes from fungi and bacteria, and that expansion of the NPP family was a feature of Phytophthora evolution.