Reoperation for interrupted aortic arch with the use of retrograde cerebral perfusion

We treated 2 patients with recurrent coarctation after repair of interrupted aortic arch. Because they had been operated on with the use of vascular prostheses, severe scarring was considered prohibitive for safe dissection. We successfully carried out anatomic repair with the use of retrograde cerebral perfusion through a left thoracotomy in both cases.

Pulmonary agenesis with interrupted aortic arch

This report describes a unique case of an infant with right pulmonary agenesis associated with interrupted aortic arch, ventricular septal defect, and aortic valvular stenosis. Blalock-Park arterial anastomosis and pulmonary arterial banding were performed without incidence. These techniques were useful for this complicated heart defect with pulmonary agenesis. The postoperative course of the patient was uneventful.

Furanodictine A and B: amino sugar analogues produced by cellular slime mold Dictyostelium discoideum showing neuronal differentiation activity

We investigated the constituents of Dictyostelium discoideum to clarify the diversity of secondary metabolites of Dictyostelium cellular slime molds and to explore biologically active substances that could be useful in the development of novel drugs. From a methanol extract of the multicellular fruit body of D. discoideum, we isolated two novel amino sugar analogues, furanodictine A (1) and B (2). They are the first 3,6-anhydrosugars to be isolated from natural sources. Their relative structures were elucidated by spectral means, and the absolute configurations were confirmed by asymmetric syntheses of 1 and 2. These furanodictines potently induce neuronal differentiation of rat pheochromocytoma (PC-12) cells.

Prevalence of age related maculopathy in a representative Japanese population: the Hisayama study

AIM

To determine the prevalence of age related maculopathy (ARM) in a representative older Japanese population.

METHODS

1486 residents of Hisayama town, Fukuoka, Japan, aged 50 years or older were examined and the presence of ARM was determined by grading from fundus examination by indirect ophthalmoscope, slit lamp, and colour fundus photographs.

RESULTS

The prevalence rate of drusen, which occurred with comparable frequency in men and women, was 9.6%. The frequency of drusen increased with age (p <0.01). Hyperpigmentation and/or hypopigmentation of the retina was present in 3.2%, geographic atrophy in 0.2%, and neovascular age related macular degeneration in 0.67%. The frequency of neovascular age related macular degeneration was significantly higher in the men (1.2% v. 0.34%, p <0.01).

CONCLUSIONS

Early and late stage ARM is less common among Japanese people than among white people in Western countries, while late stage ARM is more common among Japanese than among black people.

Corticospinal tract involvement in a variant of Guillain-Barré syndrome

To determine the involvement of the corticospinal tract in Guillain-Barré syndrome (GBS), we examined central motor conduction in patients with GBS-like symptoms and hyperreflexia using a magnetic stimulation technique. The subjects were 3 patients who exhibited ascending muscle weakness 2-4 weeks after preceding infections. Deep tendon reflexes were exaggerated in all four limbs of the 3 patients. The results of cerebrospinal fluid examinations revealed protein elevation without pleocytosis. The serum anti-GM(1) antibody titer was elevated in 2 patients. The results of nerve conduction study revealed axonal motor neuropathy and normal F-wave conduction. Central motor conduction time (CMCT) in patients with hyperreflexia was significantly delayed compared to that in patients with GBS and areflexia (p < 0.001), and the delayed CMCTs were significantly improved in the recovery periods (p < 0.001). Although hyperreflexia is a controversial symptom in patients with GBS, these findings indicate that there is functional corticospinal tract involvement in patients with a GBS variant.

Risk factors influencing early and late mortality after total cavopulmonary connection

OBJECTIVE

Among the later modifications of the Fontan type procedure, a significant alteration was introduced by de Leval and associates when they described the total cavopulmonary connection (TCPC). Although current results of TCPC have encouraged us to extend this procedure to high risk patients, risk factors influencing surgical outcome after TCPC have not been evaluated. We review our experiences with TCPC to identify which risk factors may have had a considerable impact on the outcome of patients undergoing TCPC and to clarify selection criteria of high-risk Fontan candidates for TCPC.

PATIENTS AND METHODS

We retrospectively reviewed the medical and surgical records of all 76 patients who underwent TCPC between July 1988 and August 2000. A cross-sectional review of these patients was undertaken.

RESULTS

There were eight early deaths and four late deaths. In a Fisher's exact test, the following variables were associated with an increased early mortality after TCPC: systemic ventricular morphology (right ventricle), ejection fraction of the systemic ventricle less than 60%, and prolonged cardiopulmonary bypass time (240 min or longer). The log-rank test demonstrated that heterotaxy syndrome, moderate to severe atrioventricular valve regurgitation, prolonged cardiopulmonary bypass time (240 min or longer), and prolonged aortic cross clamp time (70 min or longer) were associated with late mortality after TCPC. Six deaths occurred in eight (75%) patients who had six or more risk factors, whereas six deaths (9%) occurred in those who had five or fewer.

CONCLUSIONS

Patients with complex cardiac anomalies who have six or more risk factors should be excluded from TCPC candidates.

[Isolated cerebral and myocardial perfusion during aortic arch repair in neonates]

OBJECTIVES

To prevent possible neurologic injury after hypothermic circulatory arrest, aortic arch obstruction with cardiac defects is repaired in one stage using isolated cerebral and myocardial perfusion (ICMP). This study investigated serum S-100 protein(S-100) levels in neonates undergoing ICMP.

METHODS

Between February 2000 and January 2001, 19 neonate patients underwent repair of critical congenital heart defects. Seven of these patients with aortic coarctation(n = 3) or interrupted aortic arch (n = 4) with ventricular septal defect(ICMP group) underwent primary total repair. An arterial cannula was inserted either into the ascending aorta or into a polytetrafluoroethylene graft which was anastomosed to the innominate artery. During arch repair, a cross-clamp was placed between the innominate and left carotid arteries, and an end-to-end arch anastomosis was performed with cerebral perfusion and heart beating. During ICMP the flow was reduced to maintain a radial artery pressure of 30-45 mmHg. The remaining 12 patients underwent complete transposition of great arteries(n = 9) or total anomalous pulmonary venous connection(n = 3) using a cardiopulmonary bypass(CPB) with flow of 150-180 ml/kg/min(control group). Sequential blood samples for S-100 determinations were taken after induction of anesthesia, 30 min after aortic declamping(post-ACC), 30 min after CPB, and 24 hr after CPB.

RESULTS

There were no early and late deaths. Neurologic symptoms were not observed in any patients. Mean ICMP time in ICMP group was 17 +/- 4 min. In all patients, S-100 showed the highest value post-ACC and then declined with time. There were no differences in S-100 between the groups at any other time point.

CONCLUSIONS

Selective cerebral perfusion through the innominate artery may be able to maintain brain circulation.

Activation of signal transducer and activator of transcription 3 protects cardiomyocytes from hypoxia/reoxygenation-induced oxidative stress through the upregulation of manganese superoxide dismutase

BACKGROUND

Mice with cardiac-specific overexpression of signal transducer and activator of transcription 3 (STAT3) are resistant to doxorubicin-induced damage. The STAT3 signal may be involved in the detoxification of reactive oxygen species (ROS).

METHODS AND RESULTS

The effects of leukemia inhibitory factor (LIF) or adenovirus-mediated transfection of constitutively activated STAT3 (caSTAT3) on the intracellular ROS formation induced by hypoxia/reoxygenation (H/R) were examined using rat neonatal cardiomyocytes. Either LIF treatment or caSTAT3 significantly suppressed the increase of H/R-induced ROS evaluated by 2',7'-dichlorofluorescin diacetate fluorescence. To assess whether ROS are really involved in H/R-induced cardiomyocyte injury, the amount of creatine phosphokinase in cultured medium was examined. Both LIF treatment and caSTAT3 significantly decreased H/R-induced creatine phosphokinase release. These results indicate that the gp130/STAT3 signal protects H/R-induced cardiomyocyte injury by scavenging ROS generation. To investigate the mechanism of scavenging ROS, the effects of LIF on the induction of antioxidant enzymes were examined. LIF treatment significantly increased the expression of manganese superoxide dismutase (MnSOD) mRNA, whereas the expression of the catalase and glutathione peroxidase genes were unaffected. This induction of MnSOD mRNA expression was completely blocked by adenovirus-mediated transfection of dominant-negative STAT3. Moreover, caSTAT3 augmented MnSOD mRNA and its enzyme activity. In addition, the antisense oligodeoxyribonucleotide to MnSOD significantly inhibited both LIF and caSTAT3-mediated protective effects.

CONCLUSIONS

The activation of STAT3 induces a protective effect on H/R-induced cardiomyocyte damage, mainly by inducting MnSOD. The STAT3-mediated signal is proposed as a therapeutical target of ROS-induced cardiomyocyte injury.

Bone morphogenetic protein-2 inhibits serum deprivation-induced apoptosis of neonatal cardiac myocytes through activation of the Smad1 pathway

Bone morphogenetic protein (BMP)-2 has been shown to induce ectopic expression of cardiac transcription factors and beating cardiomyocytes in non-precardiac mesodermal cells, suggesting that BMP-2 is an inductive signaling molecule that participates in cardiac development. However, direct evidence of the effects of BMP-2 on cardiac myocytes has not been reported. To examine the role of BMP-2 and its receptors, we studied the ability of BMP-2 to promote survival of isolated neonatal rat cardiac myocytes. BMP receptors IA, IB, and II and activin receptor I were found to be expressed in myocytes, and BMP-2 phosphorylated Smad1 and p38 MAPK. Interestingly, BMP-2 promoted survival and inhibited apoptosis of serum-deprived myocytes, although it did not strongly induce hypertrophic growth. To explore the mechanisms for this protective effect, an adenovirus-based vector system was used. Similar to BMP-2, Smad1 promoted survival that was repressed by Smad6. Moreover, BMP-2 and Smad1 enhanced the expression of the anti-apoptotic molecule Bcl-x(L). Antisense oligonucleotides to bcl-x(L) attenuated the survival effected by BMP-2. Overall, our findings suggest that BMP-2 prevents apoptosis of myocytes by induction of Bcl-x(L) via a Smad1 pathway and might be a novel survival factor without any hypertrophic effect on myocytes.

Anatomically corrective repair of complete atrioventricular septal defects and major cardiac anomalies

BACKGROUND

Although satisfactory results of corrective surgery for atrioventricular septal defects (AVSDs) with complex lesions such as double-outlet right ventricle (DORV) or atrial isomerism have been reported in recent years, the optimal surgical options for isomerism hearts is still a controversial issue.

METHODS

We performed anatomically corrective repair on 13 children with balanced forms of complete AVSDs and associated major cardiac anomalies. Eight of the 13 patients had atrial isomerism (right in 1, left in 7), 5 of whom had DORV. Four others had DORV with trisomy 21, and 1 had tetralogy of Fallot. Atrial septation for isomerism with the placement of an additional prosthesis was performed on 4 patients.

RESULTS

Two hospital deaths and one late death occurred only in the isomerism group. Three reoperations were required solely in the left isomerism group: one replacement of the valved external conduit concomitantly with reconstruction of the left ventricular outflow obstruction, one mitral valve replacement for severe regurgitation of left atrioventricular valve, and one relief of progressing left ventricular outflow obstruction.

CONCLUSIONS

The results of anatomically corrective surgery for AVSDs with major associated cardiac anomalies in the nonisomerism group were excellent. The optimal surgical options for isomerism heart, however, remain a controversial issue.

Suppression of an IL-13 autocrine growth loop in a human Hodgkin/Reed-Sternberg tumor cell line by a novel IL-13 antagonist

IL-13 has been proposed to be an autocrine growth factor for Hodgkin/Reed-Sternberg tumor cells (H/RS cells). Since we have recently identified and produced a novel IL-13 antagonist (IL-13E13K) that can suppress the biological activity of IL-13, here we examined whether IL-13E13K can inhibit growth of Hodgkin lymphoma (HL)-derived cell lines. IL-13E13K not only inhibited the growth of an unstimulated H/RS cell line (L1236) but also cells that were stimulated by exogenous IL-13 in a dose-dependent manner. Several HL-derived cell lines expressed IL-13 message and protein and message for various chains of IL-13R. H/RS cell lines expressed mRNA for the IL-13R alpha 1, IL-4R alpha, and IL-2R gamma chains. However, none of these cell lines expressed the IL-13R alpha 2 chain. An H/RS cell line (L1236) internalized the ligand-receptor complex after binding to a fusion protein composed of IL-13 and a mutated form of Pseudomonas exotoxin A (IL-13-PE38QQR, or IL-13 cytotoxin), as IL-13 cytotoxin was specifically cytotoxic to H/RS cells in vitro. These results indicate that IL-13E13K and IL-13 cytotoxin can effectively suppress growth of a L1236 H/RS cell line. Therefore, additional studies should be performed to determine the expression of IL-13 and IL-13R in primary clinical samples of Hodgkin's lymphoma and both agents should be further tested in vitro and in vivo as possible therapeutic agents for HL.

Repair of total anomalous pulmonary venous connection without cardiopulmonary bypass

Two infants with asplenia syndrome and pulmonary venous obstruction underwent repair of total anomalous pulmonary venous connection without cardiopulmonary bypass in 1988. Using a side-biting clamp, an anastomosis between the left upper pulmonary vein and left superior vena cava-atrial junction was satisfactorily created without undue instability. Furthermore, both cases had the advantage of efficient growth in the anastomotic site postoperatively.

Sequence analysis of zebrafish chondromodulin-1 and expression profile in the notochord and chondrogenic regions during cartilage morphogenesis

Chondromodulin-I (ChM-I) is suggested in higher vertebrate systems to function as a key regulatory protein for cartilage development. To further understand the process of chondrogenesis and the function of ChM-I, we have cloned the zebrafish cDNA for chondromodulin-1 (chm1) and have mapped the chm1 gene locus. The expression profile of chm1 was determined during zebrafish embryonic development and compared to that of type II collagen (col2a1). Maternal chm1 transcripts were detected before midblastula transition and zygotic expression of chm1 was first observed in the notochord at the 10-somite stage. At later developmental stages, chm1 expression was detected in areas surrounding the otic vesicles, in the developing craniofacial cartilage elements, and in the chondrogenic region of the pectoral fins.

[Reconstruction of the pulmonary outflow tract without external conduit]

Between October 1987 and December 2000, 50 patients underwent reconstruction of the pulmonary outflow tract without external conduit. The primary malformation was tetralogy of Fallot with pulmonary atresia in 37, double outlet of right ventricle in 4, corrected transposition of the great arteries in 4, transposition of the great arteries with ventricular septal defect and pulmonary stenosis in 4, and double outlet of left ventricle in 2. Mean age at operation was 7.2 years, and mean body weight was 18.3 kg. To reconstruct posterior wall of the pulmonary outflow tract, interposition of autologous pericardium was performed in 24, direct anastomosis between pulmonary trunk and ventriculotomy in 13, longitudinal incision from ventriculotomy through pulmonary trunk in 12, and interposition of left atrial appendage in 1. Anterior wall was reconstructed with monocusp valved outflow patch (MVOP). There was one hospital death and no late death. At 10 years, the freedom from reoperation for pulmonary outflow tract obstruction was 100%, and freedom from reoperation for any cause was 86.6%. Transcatheter stenting for peripheral pulmonary stenosis was performed in 6 patients 2 to 10 months after operation.

Quantitative high-resolution microscopy on a suspended chain of gold atoms

High-resolution electron microscope images of a suspended gold chain were analyzed quantitatively. The images of the suspended gold chain were recorded on videotapes, during in situ observation in an ultra-high-vacuum electron microscope. The chain consisted of four gold atoms free from any substrate. Image simulation verified that the gold chain has a center-top geometry. The simulation also showed that the chain has no glue atoms spinning around the axis of the chain. A spinning gold atom was shown to give 50% of the stationary atom in gray scale. By comparing the noise level of the observed image and the gray scale of single atoms such as C, Si, S, Cu, and Au, we verified that the Si and S atoms have almost twice as large contrast as the noise (peak-to-peak), and C atoms have almost the same contrast as the noise level. The analysis showed it critical to detect a single Si and S atoms.

Two-generation reproductive toxicity study of tributyltin chloride in female rats

A two-generation reproductive toxicity study of the effects of tributyltin chloride (TBTCl) was conducted in female rats using dietary concentrations of 5, 25, and 125 ppm TBTCl. Reproductive outcomes of dams (number and body weight of pups and the percentage of live pups) and the growth of female pups (the day of eye opening and body weight gain) were significantly decreased in the 125 ppm TBTCl group. A delay in vaginal opening and impaired estrous cyclicity were also observed in the 125 ppm TBTCl group. However, an increase in anogenital distance was found in all TBTCl groups on postnatal d 1. A dose-effect relationship was observed in TBTCl-induced changes in anogenital distance. These results indicate that the whole-life exposure to TBTCl affects the sexual development and reproductive function of female rats. In addition, the TBTCl-induced increase in anogenital distance seems to suggest it may exert a masculinizing effect on female neonates. However, the concentrations of TBTCl used in this study are not environmentally relevant.

Characterization of a powerful high affinity antagonist that inhibits biological activities of human interleukin-13

Interleukin-13 (IL-13), a predominantly Th2-derived cytokine, appears to play a central pathological role in asthma, atopic dermatitis, allergic rhinitis, some parasitic infections, and cancer. We hypothesized that an IL-13 antagonist may have profound therapeutic utility in these conditions. We, therefore, mutagenized human IL-13 in which Glu at position 13 was substituted by a Lys residue. This highly purified recombinant IL-13 variant, IL-13E13K, bound with 4-fold higher affinity to the IL-13 receptor than wild-type IL-13 but retained no detectable proliferative activity on the TF-1 hematopoietic cell line. IL-13E13K competitively inhibited IL-13- and IL-4-dependent TF-1 proliferation. It also inhibited IL-13-induced STAT-6 (signal transduction and activator of transducer-6) activation in immune cells and cancer cells and reversed IL-13-induced inhibition of CD14 expression on human primary monocytes. These results demonstrate that high affinity binding and signal generation can be uncoupled efficiently in a ligand receptor interaction. These results also suggest that IL-13E13K may be a useful antagonist for the treatment of allergic, inflammatory, and parasitic diseases or even malignancies in which IL-13 plays a central role.

Expression and localization of angiogenic inhibitory factor, chondromodulin-I, in adult rat eye

PURPOSE

To determine the role in the eye of chondromodulin (ChM)-I, which has been identified in cartilage as an angiogenic inhibitor, the expression and localization and a possible function of ChM-I were investigated.

METHODS

Expression and localization of ChM-I in rat eyes were examined by RNase protection assay and in situ hybridization and by immunostaining, using an antibody against a synthetic peptide. The effect of recombinant ChM-I on tube morphogenesis of retinal endothelial cells was examined in culture.

RESULTS

The rat ChM-I gene was determined to encode the open reading frame of 334 amino acid residues, and ChM-I mRNA was exclusively expressed in cartilage, eye, and cerebellum in rats. ChM-I mRNA expression was evident in the iris-ciliary body, retina, and scleral compartments, but not in other compartments of the eye. In situ hybridization revealed mRNA expression in the ganglion cells, inner nuclear layer cells, and pigment epithelium in the retina and in the nonpigment epithelium of the ciliary body. Immunoreactive ChM-I was present in these cells and also in the vitreous body. Western blot analysis detected an approximately 25-kDa band of ChM-I presumed as a secretory form in the aqueous humor and vitreous body and an approximately 37-kDa band as a precursor form in the retina. Recombinant human ChM-I inhibited tube morphogenesis of human retinal endothelial cells in vitro.

CONCLUSIONS

These observations indicate a potential role for ChM-I in inhibition of angiogenesis in the rat eye.

Relocalization of apoptosis-inducing factor in photoreceptor apoptosis induced by retinal detachment in vivo

Apoptosis-inducing factor (AIF) is a novel mediator in apoptosis. AIF is a flavoprotein that is normally confined to the mitochondrial intermembrane space, yet translocates to the nucleus in several in vitro models of apoptosis. To investigate the role of AIF in the apoptotic process in vivo, we induced retinal detachment (RD) by subretinal injection of sodium hyaluronate, either in Brown Norway rats or in C3H mice. Apoptotic DNA fragmentation, as determined by terminal nick-end labeling, was most prominent 3 days after RD. The subcellular localization of AIF was examined by immunohistochemistry and immunoelectron microscopy. In normal photoreceptor cells, AIF was present in the mitochondrion-rich inner segment. However, AIF was found in the nucleus after RD. Photoreceptor apoptosis developed similarly in C3H control mice, and in mice bearing the gld or lpr mutations, indicating that cell death occurs independently from the CD95/CD95 ligand system. Both the mitochondrio-nuclear transition of AIF localization and the nuclear DNA fragmentation were inhibited by subretinal application of brain-derived neurotrophic factor. To our knowledge, this is the first description of AIF relocalization occurring in a clinically relevant, in vivo model of apoptosis.

Pulmonary root translocation for biventricular repair of double-outlet left ventricle

Double-outlet left ventricle is conventionally repaired with an extracardiac conduit when pulmonary stenosis is present. We report the use of pulmonary root translocation to the right ventricle to construct the posterior wall with autologous tissue and a porcine pericardial monocusp ventricular outflow patch anteriorly for 2 patients with double-outlet left ventricle. This technique allows minimization of pulmonary insufficiency, avoids coronary artery ligation with infundibulotomy, and has a major theoretical advantage for growth potential.

[A case of cervical myeloradiculopathy with positive serum anti-GT1a antibody]

A 19-year-old man with cervical myeloradiculopathy is reported. He was admitted to our hospital because of acute muscle weakness of upper limbs, which developed two weeks after respiratory tract infection. Neurologic examination revealed prominent muscular weakness of upper limbs. Deep tendon reflexes showed hyporeflexia in upper limbs and hyperreflexia in lower limbs. Serum IgG anti-GT1a antibody was detected by thin-layer chromatography and immunoblotting. Neck MRI revealed T2-weighted high intensity legions and swelling in spinal cord at third to sixth cervical segment. The muscular weakness and the cervical legion in MRI improved two weeks after steroid treatment. These findings indicate the involvement of cervical pyramidal tract as well as that of cervical roots in the patient. Neurological symptoms of the present case differed from those of pharyngeal-cervical-brachial variant (PCB) of Guillain-Barré syndrome, although serum anti-GT1a antibody was positive.

Telomerase inhibitors--oligonucleotide phosphoramidates as potential therapeutic agents

We have designed, synthesized, and evaluated using physical, chemical and biochemical assays various oligonucleotide N3'-->P5' phosphoramidates, as potential telomerase inhibitors. Among the prepared compounds were 2'-deoxy, 2'-hydroxy, 2'-methoxy, 2'-ribo-fluoro, and 2'-arabino-fluoro oligonucleotide phosphoramidates, as well as novel N3'-->P5' thio-phosphoramidates. The compounds demonstrated sequence specific and dose dependent activity with IC50 values in the sub-nM to pM concentration range.

Structures of azaspiracid analogs, azaspiracid-4 and azaspiracid-5, causative toxins of azaspiracid poisoning in Europe

Two new analogs of azaspiracid, azaspiracid-4 and azaspiracid-5, isolated from the mussel Mytilus edulis, involved in a newly emerged shellfish poisoning in Europe were determined to be 3-hydroxy-22-demethylazaspiracid and 23-hydroxy-22-demethylazaspiracid, respectively.