Correlation between carriers of Methicillin-resistant Staphylococcus aureus and the incidence of MRSA surgical site infections in orthopedic surgery patients.

OBJECTIVE: Surgical site infection (SSI) is a devastating complication in orthopedic surgery. Methicillin-resistant Staphylococcus aureus (MRSA) is a notorious organism in SSI, especially in orthopedic patients. We aimed to understand the association between MRSA carriers and the rate of SSI caused by MRSA in orthopedic patients. PATIENTS AND METHODS: We prospectively performed a cohort investigation on patients admitted to the Department of Orthopedic between April and August 2023. Samples were taken preoperatively from the nose and post-operatively in surgical wounds. All samples were grown in MeReSa Agar and defined as positive with MRSA characteristics. Data analysis was performed using SPSS Statistics. A significant difference between groups was assessed using either the Chi-square test or Fisher's exact test. Statistical significance was set at p<0.05. RESULTS: We obtained 526 nasal swabs of patients, and 140 (26.6%) samples were positive for MRSA. Our study revealed significant associations between MRSA carriers and the following factors: history of recent hospitalization (OR: 1.81; 95% CI: 1.172-2.795; p=0.007), smoking history (OR: 1.55; 95% CI: 1.011-2.383; p=0.044), and antibiotic exposures (OR: 2.19; 95% CI: 1.305-3.703; p=0.003). Our findings showed a significant association between SSI and the following factors: history of antibiotic exposures (OR: 2.89; 95% CI: 1.264-6.566; p=0.003), blood loss volume >500 ml (OR: 2.522; 95% CI: 1.245-5.108; p=0.008) and contaminated surgical wounds (OR: 5.97; 95% CI: 2.907-12.266; p=0.001). Patients with MRSA carriers tended to have an increased risk of having an MRSA SSI with an odds ratio of 3.44 (95% CI: 1.13-10.48; p=0.047). CONCLUSIONS: Our study highlights the increased risk of MRSA carriage in patients with a history of smoking, recent hospital admission, or antibiotic exposure. Our reports also identify potential risk factors for SSI, such as previous antibiotic exposure, blood loss, and contaminated wounds. Furthermore, our research establishes an association between MRSA colonization and MRSA SSI, which emphasizes the criticality of decolonization strategies. A further prospective multicenter study is needed to elaborate on our study findings.

Multivariate Analysis of Agronomic Traits in M4 Generation of Aromatic Rice Lines.

<b>Background and Objective:</b> Developing rice (<i>Oryza sativa</i> L.) varieties with increased yield potential has been a major concern for genetic improvement. This study aimed to evaluate aromatic rice lines and the relationship among their twelve agronomic traits using heatmap Pearson correlation and multivariate analysis to identify high yield lines using grain yield as a marker-trait. <b>Materials and Methods:</b> Twelve aromatic rice genotypes (eleven mutant lines and one control) were evaluated in the M₄ generation. The experiment was conducted at Tana Toraja regency following Randomized Complete Block Design (RCBD) with two replications. <b>Results:</b> The darker and lighter colour scale produced by heatmap revealed contrasting nature of genotypes. A significant positive correlation observed for yield was the number of fertile grains and grain weight per panicle, while a negative correlation was days to flowering. The first four components account for 83.46% of the total cumulative variation. Cluster analysis grouped 11 lines and one control into three clusters. <b>Conclusion:</b> The results concluded that the PB-A.5.3.45 line could be used for hybridization programs to develop high-yielding mutant-derived aromatic rice varieties for further improvement.

Analysis of existence of multidrug-resistant H58 gene in Salmonella enterica serovar Typhi isolated from typhoid fever patients in Makassar, Indonesia.

The surveillance of multidrug-resistant (MDR) H58 typhoid is highly important, especially in endemic areas. MDR strain detection is needed by using a simple PCR technique that only uses a pair of primers. This is conducted considering the detection of Salmonella Typhi strains that have been carried out so far are only using antimicrobial sensitivity tests to determine microbial resistance phenotypically and to determine genotypically using complex molecular techniques. We aimed to analyse the existence of Salmonella Typhi MDR H58 in patients with typhoid fever in Makassar, Indonesia. A total of 367 blood samples of typhoid fever patients were collected from April 2018 until April 2019. The blood sample was cultured, then confirmed via simple PCR. All of the confirmed samples were tested for susceptibility against antibiotics and molecularly analysed for MDR H58 existence using a simple PCR technique. We found 7% (27/367) of the samples to be positive by both blood culture and PCR. All 27 isolates were found to be sensitive to sulfamethoxazole/trimethoprim. The lowest drug sensitivities were to amoxicillin, at one (3.7%) of 27 isolates, and ampicillin, at 13 (48.1%) of 27 isolates. Salmonella Typhi H58 PCR results showed that one (3.7%) of 27 isolates carried a positive fragment of 993 bp that led to the H58 strain, since the deletion flanks this fragment. The isolate was also found to be resistant to amoxicillin and fluoroquinolone according to a sensitivity test. Further molecular analysis needs to be conducted to examine the single isolate that carried the 933 bp fragment.

Relationship between U83 gene variation in human herpesvirus 6 and secretion of the U83 gene product.

The betaherpesvirus human herpesvirus 6 (HHV-6) has two variants. The U83 gene product of strain HST is a chemoattractant for monocytes. Here, we describe U83 gene variations that accumulated in variants A and B. A gene-variation hot spot was examined in 36 different strains and one donor DNA sample. U83 gene variations accumulated in variant A and in reactivated variant B after transplantation. None of the variant-A viruses encoded the signal peptide found in the B variant. U83 gene sequencing suggested that the variant A and B groups were separate, and that the variant B viruses could be further divided into the HST-Z29 type and another type with a shorter signal peptide. In a eukaryotic expression system, the HST-Z29 type of U83 gene product was secreted into the medium, a frame-shifted HST-Z29 type was partially secreted, and the variant-A type and a first-methionine knockout of the HST-Z29 type were not secreted.