Management of refractory chylothorax after pediatric cardiovascular surgery.

We investigated the optimal treatment for refractory chylothorax after pediatric cardiovascular surgery. We retrospectively reviewed the cases of 15 consecutive patients who developed chylothorax after congenital heart surgery performed between December 2004 and November 2010. Among the 15 patients (12 male and 3 female; median age 13.9 months) who developed postoperative chylothorax, 10 recovered with conservative therapy, such as a low-fat diet, medium chain triglyceride-enriched diet, or total parenteral nutrition. Of the remaining 5 patients who underwent surgical treatment followed by conventional therapy, 4 showed improvement, and 1 died from cardiac failure. Surgical treatment was performed at a median of 19 days after diagnosis of chylothorax. Average drainage output of thoracocentesis for the first 5 days before thoracic duct ligation was 33.1 ml/kg/day. Duration of chylous fluid drainage was significantly longer in surgical patients than in patients who recovered with conservative therapy (p < 0.01). Surgical patients tended to be younger with lower body weight. Significant risk factors for surgical intervention were age <4 months, body weight <4 kg, and duration of drainage >10 days. In cases of refractory postoperative chylothorax, surgical therapy such as thoracic duct ligation should be considered when discharge from the drainage tube is >30 ml/kg/day or chylothorax is not improved within 10 days.

Involvement of JNK in the regulation of autophagic cell death.

Programmed cell death is a crucial process in the normal development and physiology of metazoans, and it can be divided into several categories that include type I death (apoptosis) and type II death (autophagic cell death). The Bcl-2 family proteins are well-characterized regulators of apoptosis, among which multidomain pro-apoptotic members (such as Bax and Bak) function as a mitochondrial gateway at which various apoptotic signals converge. Although embryonic fibroblasts from Bax/Bak double-knockout (DKO) mice are resistant to apoptosis, we have previously reported that these cells still die by autophagy in response to various death stimuli. In this study, we found that jun N-terminal kinase (JNK) was activated in etoposide- and staurosporine-treated, but not serum-starved, Bax/Bak DKO cells, and that autophagic cell death was suppressed by the addition of a JNK inhibitor and by a dominant-negative mutant of JNK. Studies with sek1(-/-)mkk7(-/-) cells revealed that disruption of JNK prevented the induction of autophagic cell death. Co-activation of JNK and autophagy induced autophagic cell death. Activation of JNK occurred downstream of the induction of autophagy, and was dependent on the autophagic process. These results indicate that JNK activation is crucial for the autophagic death of Bax/Bak DKO cells.

Structural and functional analysis of the apoptosis-associated tyrosine kinase (AATYK) family.

Apoptosis-associated tyrosine kinase (AATYK) is a protein kinase that is predominantly expressed in the nervous system and is involved in apoptosis and neurite growth of cerebellar granule cells. In this study, we cloned three new members of the mouse AATYK family, AATYK1B, AATYK2 and AATYK3. AATYK1B is a splicing variant of the previously reported AATYK1 (referred to as AATYK1A hereafter). In comparison with AATYK1A, these three AATYK members were characterized by having an extra N-terminal region that consists of a signal peptide-like sequence and a predicted transmembrane (TM) region, which is followed by a kinase domain and a long C-terminal domain. Both TM-containing AATYK isoforms (AATYK(+)TM: AATYK1B, 2, and 3) and TM-lacking isoform (AATYK(-)TM: AATYK1A) were recovered in membrane fractions, suggesting that AATYK(+)TM and AATYK(-)TM are transmembrane- and peripheral-membrane protein kinases, respectively. AATYK1A was recovered in the soluble fraction when the cells were treated with 2-bromo palmitate, suggesting that AATYK1A associates with membrane via palmitoylation. The kinase domain was highly conserved among all AATYK members and was shown to be catalytically active. Three AATYK family members were predominantly expressed in adult mouse brains with almost similar expression profiles: widespread distribution over the various brain regions, especially in the cerebellum and hippocampus, and up-regulated expression during development of the cerebellum. In cultured cerebellar granule cells, AATYK1 was abundantly localized in both soma and axons, AATYK2 distribution was restricted to soma, and AATYK3 was punctately present over the cells. AATYK1 was concentrated in the central domain of growth cones of dorsal root ganglion neurons. Our results indicate that AATYK family members are brain-dominant and membrane-associated kinases with slightly different distribution patterns in the developing and adult mouse brain, which may be involved in fine regulation of neuronal functions including neurite extension and apoptosis.

Double aortic arch with atresia, tapering and aneurysm of the left arch.

An adult male underwent chest radiography for a health check-up. This disclosed both thoracic vascular anomalies and a small nodular shadow in the left side of the superior mediastinum. Axial MRI and three-dimensional volume-rendering MR angiography revealed both a double aortic arch with left atretic arch proximal to the left common carotid artery (subtype 4), and also tapering and aneurysm of the left arch distal to the left subclavian artery. To the authors' knowledge, this report describes the first case of subtype 4 of atretic double arch with left arch atresia. Such thoracic vascular anomalies have been a theoretical possibility, but no cases have been reported to date.

Angioarrestin mRNA expression in early-stage lung cancers.

AIMS: Angioarrestin is a recently isolated gene, which has a novel function as an angiogenesis inhibitor. Angiogenesis plays an important role in tumorigenesis. It has been reported that the angioarrestin expression was decreased in lung cancer. We attempted to determine the influence of angioarrestin expression on clinicopathological features in patients with lung cancer who had undergone surgery. METHODS: Expression of angioarrestin messenger RNA was evaluated by a quantitative reverse transcription-polymerase chain reaction (RT-PCR) in 93 lung carcinomas and adjacent histological normal lung samples using LightCycler. RESULTS: Angioarrestin/GAPDH mRNA expression was significantly decreased in the tumor of lung cancer tissue (86.676+/-123.505) than in the normal lung tissue (1154.218+/-2003.508, p<0.0001), although only four lung cancer tissues had more than one tumor/normal ratio of angioarrestin/GAPDH mRNA expression. There was no relationship between angioarrestin gene expression and age, gender or T-status. However, decreased angioarrestin/GAPDH expression was especially seen at stage I lung cancer (54.156+/-62.783) when compared to stage II-IV lung cancer (110.315+/-151.359, p=0.0316). Decreased angioarrestin/GAPDH expression was especially seen at N0 lung cancer (56.396+/-69.941) when compared to N2 lung cancer (137.522+/-180.489, p=0.0362). CONCLUSIONS: The decreased expression of angioarrestin mRNA was the early phase phenomena for tumor progression from lung cancer. Alternatively, loss of antianiogenesis might play a role in oncogenesis for lung cancer.

[Therapeutic options which potentially cure patients with thymoma].

This study reports clinicopathologic features, treatment, and outcome of 107 thymomas, especially focusing on a combined modality program using hemithorax irradiation (HI) and restaging surgery using corticosteroid for advanced thymoma showing disseminative lesions. The use of HI after presumably total resection of the dissemination under posterolateral thoracotomy had no effect on reducing the incidence of relapsing. On the other hand, our own experience revealed that corticosteroid caused degenerative changes in the epithelial cells and lymphocytes of thymomas. The fact led us administer corticosteroid not only in preoperative setting but during postoperative HI. A better prognosis may be anticipated, although the follow up period is short and the number of patients involved is small.

Massive large bowel resection decreases bone strength and magnesium content but not calcium content of the femur in rats.

We examined the effects of massive large bowel resection (cecocolonectomy) on calcium and magnesium absorption and bone characteristics in rats. Male Sprague-Dawley rats were divided into two groups: sham-operated and cecocolonectomized rats. The rats were fed a sucrose-based diet containing casein at 250 g/kg diet for 10 d after a 9- to 10-d postoperative recovery period. Apparent magnesium absorption but not calcium absorption was lower in the resection group than in the sham group. There was a tendency of lower serum magnesium concentration (P = 0.070) but not calcium concentration (P = 0.418) in the resection group compared with the sham group. The maximum breaking force and magnesium content but not the calcium content of the femur were lower in the resection group than in the sham group. These results suggest that massive large bowel resection influences magnesium kinetics and decreases bone strength through reduction of the magnesium content of the femur in rats. Femoral breaking force was positively correlated (r = 0.617, P = 0.011) with only the magnesium content. We conclude that the changes in magnesium kinetics caused by cecocolonectomy could contribute to the fragility of bone.

SNRK, a member of the SNF1 family, is related to low K(+)-induced apoptosis of cultured rat cerebellar granule neurons.

When cerebellar granule neurons obtained from 11-day-old rats were cultured first in high K(+) medium for 4 days, followed by culture in low K(+) medium, the neurons underwent apoptosis and died. This cell death was prevented by actinomycin D, an inhibitor of RNA synthesis. Commitment time of the protective effect of RNA synthesis inhibition on the cell death was examined by adding actinomycin D at various time points after the switch to the low K(+) medium. More than 50% of the cells died when actinomycin D was added 3 h after changing to the low K(+) medium. To identify what kinds of newly synthesized genes are involved in regulation of the low K(+)-induced death, we performed PCR-based differential subtraction analysis using RNA prepared from the cultured neurons 0 and 3 h after changing to low K(+) medium. We isolated a clone that showed an increase in its mRNA level after changing to the low K(+) medium. This clone encoded the 3' untranslated region of SNRK, a serine/threonine kinase. Tissue distribution analysis showed that the mRNA was expressed mainly in the brain and testis. Developmental analysis in the brain showed that the mRNA expression increased in an age-dependent manner until P28, and was slightly decreased in adults. In situ hybridization analysis showed that the mRNA was expressed throughout the brain. The mRNA was shown to be expressed in neurons by double staining with anti-MAP2 antibody. In addition, anti-N-terminal SNRK antibody stained the nuclei of cultured rat cerebellar granule neurons. These results suggested that SNRK may be involved in regulation of low K(+)-induced apoptosis of cultured cerebellar granule neurons.

Efficient production of N-terminally truncated biologically active human interleukin-6 by Bacillus brevis.

cDNAs encoding human interleukin 6 (hIL-6) and its variants lacking the N-terminal Pro and Pro-Val-Pro-Pro, respectively, were expressed in Bacillus brevis by using the signal peptide fusion approach. The presence of Pro at the N-terminus of the mature protein hindered the action of the Bacillus brevis signal peptidase. hIL-6 lacking the N-terminal Pro-Val-Pro-Pro was most efficiently secreted in a biologically active form and accumulated in the culture medium to a level of 200 mg per liter, which is the highest level reported for the bacterial secretion of hIL-6.

BH4 domain of antiapoptotic Bcl-2 family members closes voltage-dependent anion channel and inhibits apoptotic mitochondrial changes and cell death.

A change of mitochondrial membrane permeability is essential for apoptosis, leading to translocation of apoptogenic cytochrome c and apoptosis-inducing factor into the cytoplasm. We recently showed that the Bcl-2 family of proteins regulate cytochrome c release and the mitochondrial membrane potential (Deltapsi) by directly modulating the activity of the voltage-dependent anion channel (VDAC) through binding. Here we investigated the biochemical role of the conserved N-terminal homology domain (BH4) of Bcl-x(L), which has been shown to be essential for inhibition of apoptosis, with respect to the regulation of mitochondrial membrane permeability and found that BH4 was required for Bcl-x(L) to prevent cytochrome c release and Deltapsi loss. A study using VDAC liposomes revealed that Bcl-x(L), but not Bcl-x(L) lacking the BH4 domain, inhibited VDAC activity. Furthermore, BH4 oligopeptides of Bcl-2 and Bcl-x(L), but not mutant peptides, were able to inhibit both VDAC activity on liposomes even in the presence of Bax and apoptotic Deltapsi loss in isolated mitochondria. It was also shown that the BH4 domain, fused to the protein transduction domain of HIV TAT protein (TAT-BH4), efficiently prevented apoptotic cell death. These results indicate that the BH4 of Bcl-2/Bcl-x(L) is essential and sufficient for inhibiting VDAC activity, which in turn prevents apoptotic mitochondrial changes, and for preventing apoptotic cell death. Finally, the data suggest that the TAT-BH4 peptide is potentially useful as a therapeutic agent for diseases caused by accelerated apoptosis.

Contribution of the cecum and colon to zinc absorption in rats.

We examined the role of the large intestine in zinc absorption in rats in three separate experiments. In the first experiment, we examined apparent zinc absorption in rats fed diets containing graded levels of zinc carbonate (0.015-0.535 mmol Zn/kg diet) and evaluated zinc status on the basis of the zinc concentrations in serum and several tissues. The zinc absorption and the serum zinc concentration increased with the zinc content of the diet up to 0. 153 mmol Zn/kg diet. Femoral and pancreatic zinc levels increased linearly up to 0.229 mmol Zn/kg diet. In the second experiment, a zinc carbonate suspension was administered into the cecum via an implanted cannula or into the stomach via an orogastric tube, and the rats were fed diets with or without a highly fermentable fiber, guar gum hydrolysate (GGH, 50 g/kg diet), with coprophagy prevention. The amount of instilled zinc corresponded to the amount of zinc ingested as a component of the diet by the rats of a control group, 0.229 mmol Zn/kg diet. Apparent absorption of cecally instilled zinc was approximately half that observed when zinc was administered into the stomach in both diet groups. Serum and femur zinc concentrations in the cecum-administered groups were approximately 50 and 25% lower, respectively, than those in rats administered zinc into the stomach. The results demonstrate that, in vivo, the absorptive efficiency in the large intestine is not sufficient to satisfy the rat's zinc requirement and does not change when the luminal environment is substantially altered by feeding GGH. In Experiment 3, the effects of cecocolonectomy on zinc absorption were examined in rats with gastric acid suppression. In the cecocolonectomized groups, serum zinc concentration was lower as a result of treatment with a proton pump inhibitor, omeprazole, than in vehicle-treated rats, but not in sham-operated groups. These findings suggest that the cecum and colon contribute to zinc absorption when absorption in the small intestine is impaired.

[Determination of the distance between the upper incisors and the laryngoscope blade during laryngoscopy: comparisons of the McCoy, the Macintosh, the Miller, and the Belscope blades].

We compared the distance between the upper central incisors and the laryngoscope blade with the four different types of laryngoscope blade (McCoy, Macintosh, Miller, Belscope). Twenty-three patients scheduled for general anesthesia were studied. The tooth-blade distance was measured when optimum visibility of the glottis was obtained. The visibility was determined according to the Cormack and Lehane grading. The distance with the McCoy and the Belscope was greater than that with the Macintosh or the Miller. The visibility grade was significantly worse with the Macintosh than with the other types of laryngoscope. The results indicate that the McCoy and the Belscope provide less incidence of upper dental injuries and greater visibility than either with the Macintosh or the Miller. Furthermore, the force applied to the handle is thought to be smaller with the McCoy than with the Belscope.

Participation of cathepsins B and D in apoptosis of PC12 cells following serum deprivation.

Cathepsin D, a lysosomal aspartic proteinase, has been shown to induce apoptosis of HeLa cells when overexpressed. To further understand regulatory mechanisms of cathepsin D-induced cell death, we examined whether lysosomal cysteine and aspartic proteinases are involved in apoptosis of PC12 cells following serum deprivation. In serum deprived culture, PC12 cells overexpressing cathepsin D died more rapidly than wild-type cells. When the active forms of cathepsins B and D were examined during the apoptotic process of wild-type cells, the amount of cathepsin B was drastically reduced 24 hr after the onset of culture, whereas that of cathepsin D considerably increased. The viability of PC12 cells overexpressing cathepsin B was significantly higher in serum-deprived culture than wild-type cells. In this situation, the amount of the cathepsin B protein did not decrease. The results suggest that there exists an apoptotic pathway regulated by lysosomal cathepsins B and D.

Overexpression of cation-dependent mannose 6-phosphate receptor prevents cell death induced by serum deprivation in PC12 cells.

PC12 cells express well cation-independent mannose 6-phosphate receptors (CI-MPR), but not cation-dependent (CD)-MPR as much. To examine CD-MPR dependency of transport of cathepsins B and D to lysosomes in PC12 cells, we prepared the cells overexpressing CD-MPR. Immunoreactivity for cathepsin B became more distinct and larger in size in the transfected cells than in wild-type cells. No difference in the distribution of cathepsin D was seen between these two cells. The viability of the cells following serum deprivation was significantly higher in the transfected cells than in wild-type cells. This increased viability of the transfected cells was blocked by CA074, a specific inhibitor of cathepsin B, while pepstatin A suppressed the action of CA074. The results suggest that CD-MPR preferentially transport cathepsin B in PC12 cells, and cathepsins B and D participate in the regulation of PC12 cell apoptosis.

[A comparison of the grade of laryngeal visualisation;--the McCoy compared with the Macintosh and the Miller blade in adults].

Effectiveness in visualization of the vocal cord during orotracheal intubation with McCoy (McC) compared with Macintosh (Min) and Miller (Mil) blades were investigated. After an institutional review board approval, 117 patients for elective surgery under general anesthesia requiring tracheal intubation were investigated. Five board certified anesthesiologists tried to visualize the vocal cord of a patient three times with the three different types of laryngoscope. Total of 351 intubation attempts were studied. The view obtained at laryngoscopy with each of the three blades was recorded as follows. Grade 1. If most of the glottis is visible. Grade 2. If only the posterior extremity of the glottis is visible. Grade 3. If no part of the glottis can be seen. Grade 4. If not even the epiglottis can be exposed. Eight-two Grade 1 views were obtained with McC, 72 with Mil and 47 with Min, respectively. Thirty-three Grade 2 views were obtained with McC, 36 with Min and 24 with Mil. Two Grade 3 views with McC, 34 with Min and 14 with Mil were obtained. Seven Grade 4 views were obtained with Mil. The grades of laryngeal visualization with McC were significantly lower than those with Min and Mil.

[Cervival spine movement during light-guided orotracheal intubation with lightwand stylet (Trachlight)].

We assessed the degree of movement of the cervical spine (C-spine) during light-guided orotracheal intubation using a lightwand stylet (Trachlight). Twenty ASA 1-2 patients were studied. Following induction of anesthesia and obtaining muscle relaxation, the cross-table lateral radiograph of C-spine was taken before and during the intubation with Trachlight. We measured the distance between the spinous processes of C1 and the occiput (delta C1-occiput), and the degree of displacement of C1 and C5 against C3 (delta C1 + C5) by tracing the standard and intubation films. The results showed that delta C1-occiput was larger and delta C1 + C5 was smaller with Trachlight than with conventional or McCoy laryngoscopy we had previously reported. We concluded that light-guided intubation technique using Trachlight needed less movement of the C-spine in contrast to direct laryngoscopy. We believe that Trachlight is an easy, alternative and beneficial device for patients in whom cervical spine movement is limited or undesirable.

[Which laryngoscope is the most stressful in laryngoscopy; Macintosh, Miller, or McCoy?].

Stress responses during laryngoscopy were compared among the situations using three different laryngoscopes, Macintosh (curved standard blade), Miller (straight blade), or McCoy (levering). Blood pressure, heart rate (in 58 patients) and plasma concentration of catecholamines (in 29 patients) were measured before, during and after laryngoscopy without tracheal intubation. Systolic blood pressure after laryngoscopy was significantly higher in the Miller group than in other two groups. Plasma epinephrine concentrations after laryngoscopy in the McCoy group were lower than other two groups. Heart rate and plasma norepinephrine concentration were not different among the three groups. These results suggest that the stress response during laryngoscopy without intubation is the biggest in using the Miller laryngoscope and the smallest in using the McCoy laryngoscope.

[Assessment of the practice of endotracheal intubation by levering Laryngoscope in teaching of undergraduate medical students].

Twenty-nine inexperienced medical students tried to intubate endotracheal tubes using both levering laryngoscope (McCoy laryngoscope) and Macintosh laryngoscope in adult mannikin the Cormack and Lehane Grade 2. The number of successful intubations by McCoy type was close to those by Macintosh type. Improvement in time necessary from insertion of the laryngoscope to confirmation of placement of the endotracheal tube McCoy type was also close to that by Macintosh type. But the grade of handling difficulty of McCoy type was significantly higher than that of Macintosh type, because Macintosh type was simpler to handle than McCoy type. It was suggested that Macintosh laryngoscope was more useful than McCoy laryngoscope for teaching of inexperienced medical students.

[Systemic oxygen demand and supply balance during warm heart surgery without blood transfusion].

We investigated systemic oxygen demand and supply balance during warm heart surgery without blood transfusion on 203 patients. The patients aged 63-years on average, for coronary artery bypass surgery, were assigned to extracorporeal circulation (ECC) with flow index of either 2.4 l.min-1.m-2 or 2.6. Hemoglobin concentration (Hb), mixed venous oxygen saturation (SvO2), cardiac index (CI), oxygen delivery (DO2), oxygen consumption (VO2) and oxygen extraction ratio (OER) were determined. The mean operation time was 314 min, and the mean ECC time was 94 min. In both groups, the initiation of ECC decreased Hb to 6.5 g.dl-1, and SVO2 decreased gradually during ECC. In addition, DO2 was lower than the pre-ECC level, which may indicate the shortage of oxygen supply, while VO2 and OER increased during ECC. OER increased by 0.38 in the group with flow index of 2.4, which is higher than 0.35 of the group with 2.6. The discontinuation of ECC improved oxygen profile, mainly due to the increase of Hb and CI. These findings indicate that oxygen demand and supply balance was maintained during normothermic ECC without transfusion, although longer duration o ECC may cause the shortage of oxygen supply. A higher flow may be required during normothermic ECC.