The etiology of adolescent idiopathic scoliosis

The etiology of adolescent idiopathic scoliosis (AIS), the most common form of scoliosis, is unclear. Researchers with divergent perspectives have tried to better define this etiology. Genetics, growth hormone secretion, connective tissue structure, muscle structure, vestibular dysfunction, melatonin secretion, and platelet microstructure are major areas of focus. In this article, we review the literature in these areas and present the consensus on proposed hypotheses. Studies that simplify the etiology to a single factor have been inconclusive or unsuccessful. Most likely, the etiology is multifactorial, and reported associations are links in pathogenesis rather than etiologic factors. Research is needed to better define the role of all factors in AIS development.     

Adult-to-adult living donor liver transplantation at the Asan Medical Center,Korea

Between February 1997 and December 2001, 311 adult-to-adult living donor liver transplants (A-A LDLTs) were performed at the Asan Medical Center for patients above 20 years of age. Indications for A-A LDLT were: chronic hepatitis B (203), chronic hepatitis C (5), hepatocellular carcinoma (64), alcoholic cirrhosis (9), cryptogenic cirrhosis (4), secondary biliary cirrhosis (5), primary biliary cirrhosis (1), Wilson' s disease (2), autoimmune hepatitis (1), hepatic tuberculosis (1), cholangiocarcinoma (1), fulminant hepatic failure (14) and primary non-function of cadaveric liver graft (1). Of 311 A-A LDLTs, 36 were of medical high urgency, 20 were for acute and subacute hepatic failure, 15 were for hepato-renal syndrome and 1 was for primary non-function. Recipient age ranged from 27 to 64 years. Donor age ranged from 16 to 62 years. There was no donor mortality. Implanted liver grafts were categorized into seven types: 175 modified right lobe (MRL), 70 left lobe, 32 right lobe, 20 dual grafts, 10 left lobe plus caudate lobe, three extended right lobe and one posterior segment. In MRL, the tributaries of the middle hepatic vein were reconstructed by interpositioning a vein graft. Indication for dual graft implantation was the same as single graft A-A LDLT, and four of 20 were emergency cases. Of 20 dual grafts, 14 received two left lobes, four received a left lobe and a lateral segment, one received a right lobe and a left lobe and one received a lateral segment and a posterior segment. Graft volume ranged from 28% to 83% of the standard liver volume of the recipients. There were 33 (10.6%) in-hospital mortalities (< 4 months) among the 310 patients after 311 A-A LDLTs. Of the 36 patients receiving emergency transplants, 31 survived. These encouraging results justify the expansion of A-A LDLT in coping with increasing demands, even in urgent situations. We have aimed to introduce the establishment of the efficacy of A-A LDLT in various end-stage chronic and acute liver diseases, as well as new technical advances to overcome small graft-size syndrome by using dual-graft implantation and MRL, both of which were first developed in our department.     

Randomized comparison of the effectiveness of nasal intubation using a GlideScope video laryngoscope with Magill forceps <Emphasis Type="Italic">versus</Emphasis> vascular forceps in patients with a normal airway

Purpose

The GlideScope^® video laryngoscope (GVL) is widely used for nasotracheal intubation in dental and facial plastic surgery. The angle of the Magill forceps is different from that of the GVL blade, which suggests that the Magill forceps are not the ideal forceps for use with the GVL. The purpose of this study was to compare the effectiveness of the Magill forceps vs vascular forceps for nasotracheal intubation using the GVL.

Methods

This study included 60 patients scheduled to undergo elective surgery requiring nasotracheal intubation. Patients were assigned to one of two groups—i.e., Magill forceps (group M) or vascular forceps along with a tube exchanger (group V), by computer randomization. The primary outcome was total intubation time, defined as the time from when the anesthesiologist picked up the device to the time when three successive end-tidal CO₂ waves were obtained following intubation. Secondary outcomes were blood in the endotracheal tube and trauma to the oral tissues or teeth. A blind observer assessed the presence of sore throat one hour and 24 hr after surgery.

Results

The total intubation time was significantly different between group M and group V (96.1 sec and 78.1 sec, respectively; mean difference, 18 sec; 95% confidence interval (CI), 13.7 to 49.7). The incidence of epistaxis in group M was significantly greater than that in group V (46.7% vs 16.7%, respectively; relative risk, 2.8; 95% CI, 1.2 to 6.8).

Conclusion

The total intubation time was significantly less with the vascular forceps (and tube exchanger) than with the Magill forceps. Using vascular forceps also reduced the incidence of epistaxis compared with that using the Magill forceps. Using a tube exchanger and vascular forceps offers advantages over use of Magill forceps when a GlideScope video laryngoscope is used for nasotracheal intubation.Trial registration: http://www.who.int/ictrp/network/cris2/en/, CRIS, KCT0001310. Registered 29 July 2014.

     

Investigating the effects of suicide exposure among a clinical sample of active duty service members

Suicide exposure warrants further investigation as a risk factor for suicide among military service members. This study aimed to examine associations among suicide exposure, suicidal ideation (SI), and psychological symptoms in a clinical sample of service members (N = 1,565, 64.4% suicide-exposed) and identify how one's relationship with the deceased impacts suicidality and psychological health in exposed individuals. A secondary analysis of cross-sectional survey data was conducted. Generalized linear regression analyses were used to identify associations between suicide exposure and both current SI and psychological symptoms among all participants; the associations between suicide exposure characteristics and psychological symptoms were only examined among exposed individuals. Exposure was not significantly associated with higher SI, β = .007, SE = .16, p = .965, but was associated with PTSD, β = 1.60, SE = 0.49, p = .001; anxiety, β = .68, SE = .31, p = .031; and insomnia symptoms, β = .98, SE = .25, p < .001. Among participants who had been exposed, high/long impact of exposure was positively associated with SI, β = 0.94, SE = .26, p < .001, and psychological symptoms, PTSD: β = 2.32, SE = .77, p = .002; anxiety: β = 1.39, SE = .50, p = .005; insomnia: β = .96, SE = .39, p = .015. Results illustrate the significant issue of suicide exposure within the military and show consideration of suicide exposure as a potential risk factor for adverse psychological outcomes is warranted.     

Intraoperative fluid administration volumes during pediatric liver transplantation and postoperative outcomes: A multicenter analysis

Introduction

Fluid administration is an important aspect of the management of children undergoing liver transplantation and may impact postoperative outcomes. Our aim was to evaluate the association between volume of intraoperative fluid administration and our primary outcome, the duration of postoperative mechanical ventilation following pediatric liver transplantation. Secondary outcomes included intensive care unit length of stay and hospital length of stay.

Methods

We conducted a multicenter, retrospective cohort study using electronic data from three major pediatric liver transplant centers. Intraoperative fluid administration was indexed to weight and duration of anesthesia. Univariate and stepwise linear regression analyses were conducted.

Results

Among 286 successful pediatric liver transplants, the median duration of postoperative mechanical ventilation was 10.8 h (IQR 0.0, 35.4), the median intensive care unit length of stay was 4.3 days (IQR 2.7, 6.8), and the median hospital length of stay was 13.6 days (9.8, 21.1). Univariate linear regression showed a weak correlation between intraoperative fluids and duration of ventilation (r² = .037, p = .001). Following stepwise linear regression, intraoperative fluid administration remained weakly correlated (r² = .161, p = .04) with duration of postoperative ventilation. The following variables were also independently correlated with duration of ventilation: center (Riley Children's Health versus Children's Health Dallas, p = .001), and open abdominal incision after transplant (p = .001).

Discussion

The amount of intraoperative fluid administration is correlated with duration of postoperative mechanical ventilation in children undergoing liver transplantation, however, it does not seem to be a strong factor.

Conclusions

Other modifiable factors should be sought which may lead to improved postoperative outcomes in this highly vulnerable patient population.     

Arthroscopic physeal sparing all inside repair of the tibial avulsion fracture in the anterior cruciate ligament: technical note

We describe a new and effective arthroscopic physeal sparing repair of the tibial eminence avulsion fracture using all an inside repair technique. The treatment of ACL avulsion is controversial, especially in skeletally immature patients, with concerns about physeal damage, and a more reliable way of fixation is still being pursued for small or comminuted fragments. Screw fixation and suture cerclage has some limitations, especially in the small fragment or skeletally immature patients. We fixed avulsion fragment using all inside repair between the distal portion of the ACL and transverse ligament and periosteum. A crescent suture hook loaded with NO. 0 PDS is introduced and the suture hook pierces the transverse intermeniscal ligament and periosteum. The half length of the PDS is now advanced out through the hook and the end is brought out to the anterolateral portal. With the suture hook located intra-articularly and loaded with half the length of the original PDS, the suture hook repierces the transverse intermeniscal ligament at 5 mm on the side and the remaining half length of PDS is now advanced out through the hook and the end is brought out to the anterolateral portal. After that procedure, the suture hook loaded with NO. 0 absorbable Maxon is introduced through the anteromedial portal for the role of shuttle relay. The suture hook pierces the ACL just above the superior border of the avulsion fragment, the Maxon is now advanced out through the hook and the end is brought out to the anterolateral portal. Subsequently, the suture hook is removed and a suture retriever is introduced through the anterolateral portal. PDS and Maxon are held together and retrieved out of the anterolateral portal by the suture retriever at the same time. Our technique has advantages in small comminuted fractures and skeletally immature patients.     

Delayed presentation of arteriovenous fistula and pseudoaneurysms in a renal transplant patient 10 years after percutaneous allograft biopsy

A 51-year-old man was admitted with microscopic hematuria at 10 years after living donor renal transplantation. In order to distinguish between acute tubular necrosis and acute rejection, a graft biopsy was performed under ultrasound guidance at 1 month posttransplantation. Doppler sonography revealed 3 pulsatile cystic masses and an arteriovenous fistula (AVF) in the lower kidney pole. Selective transplant renal angiography revealed 3 pseudoaneurysms with an AVF supplied by a lobular artery in the lower pole. The diagnosis was AVF with pseudoaneurysm, which developed secondary to percutaneous renal allograft biopsy. Interventional treatment was performed because of the high risk for pseudoaneurysm rupture. The AVF and pseudoaneurysms were treated successfully by percutaneous transluminal embolization; renal function remained stable after embolization.     

Subtraction MR Venography Acquired from Time-Resolved Contrast-Enhanced MR Angiography: Comparison with Phase-Contrast MR Venography and Single-Phase Contrast-Enhanced MR Venography

ObjectiveTo evaluate the image characteristics of subtraction magnetic resonance venography (SMRV) from time-resolved contrast-enhanced MR angiography (TRMRA) compared with phase-contrast MR venography (PCMRV) and single-phase contrast-enhanced MR venography (CEMRV).ResultsSingle-phase contrast-enhanced MR venography showed better image quality (median score 4 in both reviewers) than did the other two MRVs (p < 0.001), whereas SMRV (median score 3 in both reviewers) and PCMRV (median score 3 in both reviewers) had similar image quality (p ≥ 0.951). SMRV (median score 0 in both reviewers) suppressed arterial signal better than did the other MRVs (median score 1 in CEMRV, median score 2 in PCMRV, both reviewers) (p < 0.001). The dural sinus score of SMRV (median and interquartile range [IQR] 48, 43-50 for reviewer 1, 47, 43-49 for reviewer 2) was significantly higher than for PCMRV (median and IQR 31, 25-34 for reviewer 1, 30, 23-32 for reviewer 2) (p < 0.01) and did not differ from that of CEMRV (median and IQR 50, 47-52 for reviewer 1, 49, 45-51 for reviewer 2) (p = 0.146 in reviewer 1 and 0.123 in reviewer 2). The SNR and CNR of SMRV (median and IQR 104.5, 83.1-121.2 and 104.1, 74.9-120.5, respectively) were between those of CEMRV (median and IQR 150.3, 111-182.6 and 148.4, 108-178.2) and PCMRV (median and IQR 59.4, 49.2-74.9 and 53.6, 43.8-69.2).ConclusionSubtraction magnetic resonance venography is a promising MRV method, with acceptable image quality and good arterial suppression.     

Cyclosporine-induced renal injury induces toll-like receptor and maturation of dendritic cells

BACKGROUND: The toll-like receptor (TLR) is stimulated by not only pathogen-associated molecular patterns but also endogenous TLR ligands provided by injured cells. The influence of cyclosporine A (CsA)-induced renal injury on TLR expression and subsequent signaling pathway was evaluated. METHODS: Induction of chronic CsA nephropathy was made by administering CsA (15 mg/kg/day) for 28 days in rats. The TLR2 and TLR4 mRNA and protein expression, TLR-signaling pathway (MYD88, NF-kappaB and AP-1), putative TLR ligand (heat shock protein 70 [HSP70]), and maturation of dendritic cells were evaluated in CsA-treated rat kidneys. RESULTS: Long-term CsA treatment upregulated TLR2 and TLR4 mRNA and protein expression on renal tubular cells, and these were accompanied by increased MYD88, NF-kappaB and AP-1 expression. Putative TLR ligand (HSP70) was also significantly increased in CsA-treated rat kidney compared with vehicle-treated rat kidney. CsA-treatment increased expression of TNF-alpha mRNA, the number of dendritic cells, and expression of MHC class II antigen. Double-labeling of markers of dendritic cells and MHC class II antigen revealed that matured dendritic cells increased in CsA-treated rat kidney. CONCLUSIONS: CsA-induced renal injury stimulates components of innate immunity, and this finding suggests close association between CsA-induced renal injury and activation of innate immunity.     

Sirolimus inhibits platelet-derived growth factor-induced collagen synthesis in rat vascular smooth muscle cells

Vascular smooth muscle cell (VSMC) proliferation and extracellular matrix (ECM) accumulation play key roles in the development and the progression of vascular remodeling such as transplant arteriosclerosis and restenosis. The present study examined the effects of sirolimus (SRL) on platelet-derived growth factor (PDGF)-induced fibronectin secretion, collagen synthesis, and the related signaling pathways including reactive oxygen species (ROS) and mitogen-activated protein kinases (MAPK) in rat VSMCs. Primary rat VSMCs were isolated from male Sprague-Dawley rats. Growth arrested, synchronized cells were treated with various concentrations of SRL before the addition of PDGF at 10 ng/mL. Proliferating cell nuclear antigen expression, fibronectin secretion, and the activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK were assessed by Western blot analysis, collagen synthesis by [(3)H]-proline incorporation, and cellular ROS by flow cytometry. PDGF (10 ng/mL) increased VSMC proliferation by 1.7-fold, fibronectin secretion by 1.5-fold, collagen synthesis by 2.1-fold, cellular ROS by 1.6-fold, and activation of ERK and p38 MAPK by 3.3- and 3.9-fold compared to controls. SRL above 1 nmol/L inhibited PDGF-induced VSMC proliferation and collagen synthesis but not PDGF-induced fibronectin secretion, cellular ROS, and activation of ERK and p38 MAPK. These data demonstrated that PDGF increased ECM synthesis as well as proliferation through cellular ROS and subsequent MAPK activation and that SRL inhibited PDGF-induced VSMC proliferation and collagen synthesis in a cellular ROS- and MAPK activation-independent way.