IMPORTANCE: DNA modification plays a crucial role in bacterial regulation. Despite several examples demonstrating the role of methyltransferase (MTase) enzymes in bacterial virulence, investigation of this phenomenon on a whole-genome scale has remained elusive until now. Here we used single-molecule real-time (SMRT) sequencing to determine the first complete methylome of a strain from the multidrug-resistant E. coli sequence type 131 (ST131) lineage. By interrogating the methylome computationally and with further SMRT sequencing of isogenic mutants representing previously uncharacterized MTase genes, we defined the target sequences of three novel ST131-specific MTases and determined the genomic distribution of all MTase target sequences. Using a large collection of 95 previously sequenced ST131 genomes, we identified mobile genetic elements as a major factor driving diversity in DNA methylation patterns. Overall, our analysis highlights the potential for DNA methylation to dramatically influence gene regulation at the transcriptional level within a well-defined E. coli clone.
METHODS: Miri General Hospital is a remote center in Sarawak, Malaysia, serving a population with difficult access to neurosurgical services. Two neurosurgeons were stationed here on a rotational basis every fortnight during the pandemic to handle neurosurgical cases. Patients were triaged depending on their urgent needs for surgery or transfer to a neurosurgical center and managed accordingly. All patients were screened for potential risk of contracting COVID-19 prior to the surgery. Based on this, the level of personal protective equipment required for the health care workers involved was determined.
RESULTS: During the initial 6 weeks of the Movement Control Order in Malaysia, there were 50 urgent neurosurgical consultations. Twenty patients (40%) required emergency surgery or intervention. There were 9 vascular (45%), 5 trauma (25%), 4 tumor (20%), and 2 hydrocephalus cases (10%). Eighteen patients were operated at Miri General Hospital, among whom 17 (94.4%) survived. Ninety percent of anticipated transfers were avoided. None of the medical staff acquired COVID-19.
CONCLUSIONS: This framework allowed timely intervention for neurosurgical emergencies (within a safe limit), minimized transfer, and enabled uninterrupted neurosurgical services at a remote center with difficult access to neurosurgical care during a pandemic.
METHODS: We conducted an online survey among neurosurgery residents in Indonesia, Malaysia, Philippines, Singapore, and Thailand from May 22 to 31, 2020 using Google Forms. The 33-item questionnaire collected data on elective and emergency neurosurgical operations, ongoing learning activities, and health worker safety.
RESULTS: A total of 298 of 470 neurosurgery residents completed the survey, equivalent to a 63% response rate. The decrease in elective neurosurgical operations in Indonesia and in the Philippines (median, 100% for both) was significantly greater compared with other countries (P < 0.001). For emergency operations, trainees in Indonesia and Malaysia had a significantly greater reduction in their caseload (median, 80% and 70%, respectively) compared with trainees in Singapore and Thailand (median, 20% and 50%, respectively; P < 0.001). Neurosurgery residents were most concerned about the decrease in their hands-on surgical experience, uncertainty in their career advancement, and occupational safety in the workplace. Most of the residents (n = 221, 74%) believed that the COVID-19 crisis will have a negative impact on their neurosurgical training overall.
CONCLUSIONS: An effective national strategy to control COVID-19 is crucial to sustain neurosurgical training and to provide essential neurosurgical services. Training programs in Southeast Asia should consider developing online learning modules and setting up simulation laboratories to allow trainees to systematically acquire knowledge and develop practical skills during these challenging times.
OBJECTIVE: We hypothesized that the risk of infections after primary cranioplasty in adult patients who underwent craniectomies for non-infection-related indications are no different when performed early or delayed. We tested this hypothesis in a prospective, multicenter, cohort study.
METHODS: Data were collected prospectively from 5 neurosurgical centers in the United Kingdom, Malaysia, Singapore, and Bangladesh. Only patients older than 16 years from the time of the non-infection-related craniectomy were included. The recruitment period was over 17 months, and postoperative follow-up was at least 6 months. Patient baseline characteristics, rate of infections, and incidence of hydrocephalus were collected.
RESULTS: Seventy patients were included in this study. There were 25 patients in the early cranioplasty cohort (cranioplasty performed before 12 weeks) and 45 patients in the late cranioplasty cohort (cranioplasty performed after 12 weeks). The follow-up period ranged between 16 and 34 months (mean, 23 months). Baseline characteristics were largely similar but differed only in prophylactic antibiotics received (P = 0.28), and primary surgeon performing cranioplasty (P = 0.15). There were no infections in the early cranioplasty cohort, whereas 3 infections were recorded in the late cohort. This did not reach statistical significance (P = 0.55).
CONCLUSIONS: Early cranioplasty in non-infection-related craniectomy is relatively safe. There does not appear to be an added advantage to delaying cranioplasties more than 12 weeks after the initial craniectomy in terms of infection reduction. There was no significant difference in infection rates or risk of hydrocephalus between the early and late cohorts.
METHODS: This was a randomized controlled trial at 2 centers. A total of 78 patients requiring DC were randomized in a 1:1:1 ratio into 3 groups: vacuum drains (VD), passive drains (PD), and no drains (ND). Complications studied were need for surgical revision, SGH amount, new remote hematomas, postcraniectomy hydrocephalus (PCH), functional outcomes, and mortality.
RESULTS: Only 1 VD patient required surgical revision to evacuate SGH. There was no difference in SGH thickness and volume among the 3 drain types (P = 0.171 and P = 0.320, respectively). Rate of new remote hematoma and PCH was not significantly different (P = 0.647 and P = 0.083, respectively), but the ND group did not have any patient with PCH. In the subgroup analysis of 49 patients with traumatic brain injury, the SGH amount of the PD and ND group was significantly higher than that of the VD group. However, these higher amounts did not translate as a significant risk factor for poor functional outcome or mortality. VD may have better functional outcome and mortality.
CONCLUSIONS: In terms of complication rates, VD, PD, and ND may be used safely in DC. A higher amount of SGH was not associated with poorer outcomes. Further studies are needed to clarify the advantage of VD regarding functional outcome and mortality, and if ND reduces PCH rates.
METHODS: This retrospective study presents a total of 257 operations in 243 patients from 2 hospitals. A total of 130 cases were operated under LA sedation in hospital 1 and 127 cases under GA in hospital 2. Patient demographics and presenting features were similar at baseline.
RESULTS: Values are shown as LA sedation versus GA. Postoperatively, most patients recovered well in both groups with Glasgow Outcome Scale scores of 4-5 (96.2% vs. 88.2%, respectively). The postoperative morbidity was significantly increased by an odds ratio of 5.44 in the GA group compared with the LA sedation group (P = 0.005). The mortality was also significantly higher in the GA group (n = 5, 3.9%) than the LA sedation group (n = 0, 0.0%; P = 0.028). The CSDH recurrence rate was 4.6% in the LA sedation group versus 6.3% in the GA group. No intraoperative conversion from LA sedation to GA was reported.
CONCLUSIONS: This study demonstrates that CSDH drainage under LA sedation is safe and efficacious, with a significantly lower risk of postoperative mortality and morbidity when compared with GA.
METHODS: Sixty-one patients with mTBI (Glasgow Coma Scale score 13-15) were recruited prospectively, categorized according to baseline computed tomography findings, and subjected to neuropsychological assessment at initial admission (n = 61) as well as at a 6-month follow-up (n = 30). The paired t test, Cohen's d effect size calculation, and repeated-measures analysis of variance were used to establish the differences between the 2 groups in terms of neuropsychological performance.
RESULTS: A trend toward poorer neuropsychological performance among the patients with complicated mTBI was observed during admission; however, performance in this group improved over time. In contrast, the uncomplicated mTBI group showed slower recovery, especially in tasks of memory, visuospatial processing, and executive functions, at follow-up.
CONCLUSIONS: Our findings suggest that despite the broad umbrella designation of mTBI, the current classification schemes of injury severity for mild neurotrauma should be revisited. They also raise questions about the clinical relevance of both traumatic focal lesions and the absence of visible traumatic lesions on brain imaging studies in patients with milder forms of head trauma.