Jun Hyung Lee

Effects of remifentanil on cardiovascular and bispectral index responses to endotracheal intubation in severe pre-eclamptic patients undergoing Caesarean delivery under general anaesthesia

BACKGROUND We examined the effects of remifentanil on cardiovascular and bispectral index (BIS) responses to tracheal intubation and neonatal outcomes in pre-eclamptic patients undergoing Caesarean delivery under general anaesthesia. METHODS Forty-two women with severe pre-eclampsia were randomly assigned to receive either remifentanil 1 microg kg(-1) (n=21) or saline (n=21) over 30 s before induction of anaesthesia using thiopentone 4 mg kg(-1) and suxamethonium 1.5 mg kg(-1). Mean arterial pressure (MAP), heart rate (HR) and BIS values as well as plasma catecholamine concentrations were measured. Neonatal effects were assessed using Apgar scores and umbilical cord blood gas analysis. RESULTS Induction with thiopentone caused a reduction in MAP and BIS in both remifentanil and control groups. Following the tracheal intubation MAP and HR increased in both groups, the magnitude of which was lower in the remifentanil group. BIS values also increased, of which magnitude did not differ between the groups. Norepinephrine concentrations increased significantly following the intubation in the control, while remained unaltered in the remifentanil group. The neonatal Apgar scores at 1 min were significantly lower in the remifentanil group than in the control. However, Apgar scores at 5 min, and umbilical artery and vein blood gas values were similar between the groups. CONCLUSIONS These results suggest that a single bolus of 1 microg kg(-1) remifentanil effectively attenuates haemodynamic but not BIS responses to tracheal intubation in pre-eclamptic patients undergoing Caesarean delivery under general anaesthesia. However, its use was associated with maternal hypotension and neonatal respiratory depression requiring resuscitation.

Cardiovascular and arousal responses to laryngoscopy and tracheal intubation in patients with complete spinal cord injury

BACKGROUND We aimed to determine whether the autonomic and arousal responses to laryngoscopy and tracheal intubation were altered in patients with spinal cord injury (SCI). METHODS One hundred and sixteen patients with traumatic complete SCI were grouped according to the time elapsed after the injury (<3 days and >9 months) and the level of injury (above T5 and below T5): acute high (AH, n=25), chronic high (CH, n=26), acute low (AL, n=20), and chronic low (CL, n=45). Twenty-five patients without SCI served as a control group. Bispectral index (BIS) response, systolic arterial pressure (SAP), heart rate (HR), and plasma concentrations of catecholamines and arginine vasopressin were measured. RESULTS Both CH and CL groups showed a greater reduction in BIS values after induction of anaesthesia with thiopental compared with controls (P<0.05). However, BIS values after intubation increased similarly in all groups from the value measured just before laryngoscopy. SAP increased in the AL and CL and control groups but not in the AH and CH groups. HR increased significantly in all groups; though to a lesser degree in the AH compared with the other groups. Plasma norepinephrine concentrations increased in all except the AH group, but vasopressin concentrations were unchanged. CONCLUSIONS The arousal response to laryngoscopy and tracheal intubation as measured by BIS is not altered in SCI, but cardiovascular and catecholamine responses may be changed depending on time elapsed and the level of the injury. However, an identical dose of thiopental may reduce BIS value after intubation more profoundly in patients with chronic SCI.

Coexistence of JAK2 and CALR mutations and their clinical implications in patients with essential thrombocythemia

Janus kinase 2 (JAK2) and calreticulin (CALR) constitute the two most frequent mutations in essential thrombocythemia (ET), and both are reported to be mutually exclusive. Hence, we examined a cohort of 123 myeloproliferative neoplasm (MPN) patients without BCR-ABL1 rearrangement and additional ET patients (n=96) for coexistence of JAK2 and CALR mutations. The frequency of CALR mutations was 20.3% in 123 MPN patients; 31.1% in ET (n=74), 25% in primary myelofibrosis (n=4) and 2.2% in polycythemia vera (n=45). JAK2 and CALR mutations coexisted in 7 (4.2%) of 167 ET patients. Clinical characteristics, progression-free survival (PFS), and elapsed time to achieve partial remission across 4 groups (JAK2+/CALR+, JAK2+/CALR-, JAK2-/CALR+, JAK2-/CALR-) were reviewed. The JAK2+/CALR- group had higher leukocyte counts and hemoglobin levels and more frequent thrombotic events than JAK2-/CALR- group. JAK2 mutations have a greater effect on the disease phenotype and the clinical features of MPN patients rather than do CALR mutation. JAK2+ groups showed a tendency of poor PFS than JAK2- groups regardless of CALR mutation. CALR+ was a predictor of late response to the treatment. Our study also showed that thrombosis was more frequent in ET patients with type 2 CALR mutations than in those with type 1 CALR mutations.

Identification of HLA‐B*58:01:21, a novel allele in a Korean individual

B*58:01:21 has a single nucleotide change, c.264A>G (ACA→ACG at codon 88) compared with B*58:01:01:01.

Clinicopathological Implications of Mitochondrial Genome Alterations in Pediatric Acute Myeloid Leukemia

Background To the best of our knowledge, the association between pediatric AML and mitochondrial aberrations has not been studied. We investigated various mitochondrial aberrations in pediatric AML and evaluated their impact on clinical outcomes. Methods Sequencing, mitochondrial DNA (mtDNA) copy number determination, mtDNA 4,977-bp large deletion assessments, and gene scan analyses were performed on the bone marrow mononuclear cells of 55 pediatric AML patients and on the peripheral blood mononuclear cells of 55 normal controls. Changes in the mitochondrial mass, mitochondrial membrane potential, and intracellular reactive oxygen species (ROS) levels were also examined. Results mtDNA copy numbers were about two-fold higher in pediatric AML cells than in controls (P<0.0001). Furthermore, a close relationship was found between mtDNA copy number tertiles and the risk of pediatric AML. Intracellular ROS levels, mitochondrial mass, and mitochondrial membrane potentials were all elevated in pediatric AML. The frequency of the mtDNA 4,977-bp large deletion was significantly higher (P< 0.01) in pediatric AML cells, and pediatric AML patients harboring high amount of mtDNA 4,977-bp deletions showed shorter overall survival and event-free survival rates, albeit without statistical significance. Conclusions The present findings demonstrate an association between mitochondrial genome alterations and the risk of pediatric AML.

Identification of the novel HLA-B*15:18:01:04 in a Korean individual

HLA‐B*15:18:01:04 differs from HLA‐B*15:18:01:02 by single nucleotide substitution at position 2176 (G > A).

HLA‐B*40:302, a novel allele identified by sequence‐based typing in a Korean individual

B*40:302 differs from B*40:02:01:01 by a single nonsynonymous nucleotide substitution at codon 81 (CCG→CTG).