Immunogenicity of dendritic-tumor fusion hybrids and their utility in cancer immunotherapy

Cancer immunotherapy using fusion hybrid cells generated from dendritic cells (DCs) and tumor cells may be more effective than other DC-based vaccines. DC-tumor fusion potentially confers not only the DCs' antigen-presenting functionality but also a continuing source of endogenous tumor antigens for major-histocompatibility-complex-restricted T-cell sensitization. In animal models, many investigators demonstrated that vaccination with fusion hybrids was protective against tumor challenge and therapeutic, resulting in the regression of established tumors. In clinical trials for patients with a variety of metastatic diseases, fusion hybrid vaccines were well tolerated, but the overall objective response rate was only 10.9%. Careful scrutiny of a large number of publications revealed that, in most cases, no definitive evidence of heterokaryonic fusion cell formation was found. Further corroboration of this conclusion comes from reports that fusion hybrids generated from autologous (syngeneic) and allogeneic DCs displayed equivalent immunological function and therapeutic effects in vitro and in vivo. This puzzling finding suggests that effective fusion immunotherapy depends on tumor antigen scavenging and presentation by antigen-presenting cells (APCs) of host origin and is in violation of the basic tenet of the principle of DC function. We believe that conclusions drawn from reported clinical trials have not properly evaluated the efficacy of the DC-tumor hybrid vaccine, and therefore, they neither confirm nor disclaim the potential benefits that may be derived from this form of immunotherapy.

Ansa Cervicalis-to-Recurrent Laryngeal Nerve Anastomosis for Unilateral Vocal Fold Paralysis: Experience of a Single Institution

Objectives:

One treatment option for unilateral vocal fold paralysis (UVFP) is ansa cervicalis-to-recurrent laryngeal nerve (ansa-RLN) anastomosis to provide reinnervation to the affected vocal fold. The advantages of this treatment approach are that it 1) provides vocal fold tone, bulk, and tension, 2) is technically simple, and 3) does not preclude other medialization procedures. We present all patients who have undergone ansa-RLN anastomosis for UVFP at our institution.

Methods:

An Institutional Review Board-approved retrospective chart review was performed to include all patients who had undergone an ansa-RLN anastomosis procedure for UVFP at our institution. Data from clinical and endoscopic laryngoscopy with stroboscopy were recorded. Statistical analysis was performed on visual and perceptual vocal data.

Results:

A total of 46 patients were included in the study. Stroboscopic analysis and perceptual vocal evaluation was performed in a blinded fashion on the 21 patients who had preoperative and postoperative stroboscopy. Severity, roughness, breathiness, and strain all improved significantly over time. Glottic closure, vocal fold edge, and supraglottic effort all significantly improved after operation. Of the 38 patients with at least 3 months of follow-up, all except 1 demonstrated evidence of reinnervation.

Conclusions:

This technique for treating UVFP results in significant improvements in patients' voice and on visual examination.

Risk factors for hypopharyngeal/upper esophageal stricture formation after concurrent chemoradiation

BACKGROUND

Concurrent chemoradiation therapy has been demonstrated to be effective as an organ-sparing treatment for select advanced head and neck squamous cell carcinoma (HNSCC). However, this treatment modality is not without side effects. One side effect is the formation of upper esophageal strictures. As concurrent chemoradiation treatment is used more frequently, it is important to identify risk factors associated with stricture formation.

METHODS

A retrospective chart review of all patients who had undergone definitive concurrent chemoradiation treatment between 1989 and 2002 was performed. Exclusion criteria included death within 1 year or persistent/recurrent disease that required surgical salvage at the primary site. The outcome measure was stricture formation as determined by both objective findings (barium swallow or endoscopy) and the need for dilation after treatment.

RESULTS

Of the 222 patients in this cohort, there were enough data for 199 patients to assess for stricture formation. Strictures developed in a total of 41 patients (21%). Significant predictive factors were a twice-daily (BID) radiation fractionation (p = .007), female sex (p = .015), and a hypopharyngeal primary site (p = .01). Age and tumor extent were not significant factors in stricture formation (p = .15 and p = .23, respectively).

CONCLUSIONS

Symptomatic strictures occur in 21% of patients undergoing concurrent chemoradiation for HNSCC. Female sex, BID radiation fractionation, and a hypopharyngeal primary site are significant predictive factors for stricture formation.

Comparison of frontal pneumatization patterns between Koreans and Caucasians

OBJECTIVE

To evaluate the prevalence of specific frontal recess cells in Korean and Caucasian populations; to evaluate and compare the relationship between anterior skull base length and frontal recess pneumatization in these two populations.

MATERIALS AND METHODS

Frontal recess anatomy was studied with high resolution sinus CT scans obtained in 60 Korean adults and 41 Caucasian adults. None of the subjects had a history of frontal sinus disease or trauma. The anterior cranial base length (ACBL, distance between the nasion and center of the pituitary fossa) and anterior ethmoid length (AEL, distance between the nasion and upper attachment of basal lamella) was also measured on each side.

RESULTS

Supraorbital ethmoid cells were more common in Caucasians whereas suprabullar cells and recessus terminalis were more common in Koreans. The prevalence of some frontal recess pneumatization patterns (specifically supraorbital ethmoid cell, suprabullar cell, and recessus terminalis) were more commonly associated with race rather than with ACBL or AEL.

CONCLUSION

Frontal recess pneumatization patterns differ in the Korean and Caucasian adult populations. Because corresponding differences in skull base length were not identified, these differences seem likely to reflect other factors. Such information has clinical significance for frontal recess surgery in these patient populations.

Acute external laryngotracheal trauma: diagnosis and management

Laryngotracheal trauma may result in lifelong complications or even death if diagnosis or treatment is delayed. Emergency room physicians, trauma surgeons, anesthesiologists, and especially otolaryngologists should maintain a high level of awareness of and suspicion for laryngotracheal trauma whenever a patient presents with multiple trauma in general or with cervical trauma in particular. Although there is some controversy regarding care, treatment in experienced hands will usually result in a favorable outcome. In this article, we review and update the diagnosis and management of acute external laryngotracheal trauma.

Acute External Laryngotracheal Trauma: Diagnosis and Management

Laryngotracheal trauma may result in lifelong complications or even death if diagnosis or treatment is delayed. Emergency room physicians, trauma surgeons, anesthesiologists, and especially otolaryngologists should maintain a high level of awareness of and suspicion for laryngotracheal trauma whenever a patient presents with multiple trauma in general or with cervical trauma in particular. Although there is some controversy regarding care, treatment in experienced hands will usually result in a favorable outcome. In this article, we review and update the diagnosis and management of acute external laryngotracheal trauma.

A Pneumatic Orthotic Cranial Molding Helmet for Correcting Positional Plagiocephaly

The objective of this study was o determine the efficacy of a newly developed pneumatic orthotic cranial molding helmet for correcting positional plagiocephaly. The design was retrospective and the setting was a tertiary care center. Subjects were all patients in whom positional plagiocephaly has been diagnosed and who have been fitted by the Orthotics and Prosthetics Department for the helmet. Diagonal cranial lengths and widths were measured at each visit. Analysis included the calculation of the ratio change in oblique diameters compared with time, patient's age, and head circumference. Seventy-five patients met inclusion criteria (50 boys, 25 girls). Patients with pneumatic orthotic cranial molding helmet therapy had significantly improved outcomes as compared with pretreatment measurements (P < or = 0.0001). The helmet did not limit cranial growth as evidenced by significant normalization of the oblique measurement ratio when compared with increasing cranial circumference and age (P = 0.0003, P < or = 0.0001, respectively). The pneumatic orthotic cranial molding helmet successfully corrects positional plagiocephaly and does not hinder cranial growth.

First Case of Laryngeal Glomangiomyoma

Glomus tumors are derived from the normal glomus body, which is an arteriovenous confluence involved with thermoregulation. These true glomus tumors are different from the "glomus tumors" derived from the paraganglion system often encountered by the otolaryngologist. Glomus tumors have been reported in a variety of locations including the pancreas, perineum, nasal cavity, and torso; however, most are found in the extremities. We present the first case of a laryngeal glomangiomyoma. Furthermore, this lesion was successfully excised endoscopically with a CO2 laser.

Laryngotracheal Consequences of Pediatric Cardiac Surgery

OBJECTIVE

To determine the incidence and character of clinically significant laryngotracheal anomalies in pediatric patients undergoing surgical repair of congenital cardiac defects at a tertiary care center.

DESIGN

Single-center retrospective review.

PATIENTS

The charts of pediatric patients who required surgical treatment for congenital heart disease over a 4-year period were reviewed. Forty-eight of 1957 patients were seen in inpatient consultation by the otolaryngology service. The parameters studied included cardiac diagnosis, reason for consultation, findings on examination, and follow-up.

RESULTS

There were 16 (33%) cases of subglottic stenosis, which were graded according to the Cotton-Myer classification system as follows: grade 1 (n=8); grade 2 (n=3); and grade 3 (n=5). Three of the 16 patients with subglottic stenosis required tracheotomy and 4 required laryngotracheal reconstruction. Nine (19%) of the 48 patients were diagnosed as having unilateral true vocal cord paralysis and 3 (6%) as having bilateral paralysis. With the exception of 1 patient, all patients with true vocal cord paralysis on the left side had undergone repair of the aortic arch.

CONCLUSIONS

Pediatric patients with congenital cardiac disease are predisposed to laryngeal anomalies owing to (1) frequent intubation, (2) prolonged ventilatory support, and (3) recurrent laryngeal nerve injury. In our patients, subglottic stenosis was the most common laryngeal abnormality. When recognized early, in the eschar phase, most of these cases can be managed with sequential endoscopic debridement, which is conceptually similar to debridement that is performed after functional endoscopic sinus surgery. Established stenosis requires more vigorous intervention, the invasive degree of which depends on the length and circumference of the narrowing. Unilateral vocal paralysis tends to be a self-limited problem, while an elegant solution to bilateral paralysis remains elusive.

3D computed tomographic analysis of frontal recess anatomy in patients without frontal sinusitis

OBJECTIVE

Describe frontal sinus pneumatization in patients with no history of frontal sinus disease.

STUDY DESIGN AND METHODS

All 1-mm axial sinus CT scans performed from 2001 through 2003 were eligible for review on a CBYON Suite workstation (CBYON, Mountain View, CA). Exclusion criteria included frontal sinusitis, sinonasal polyposis, age < 18 years, sinus malignancy, fibroosseous lesions, maxillofacial trauma, congenital anomaly, and sinus surgery.

RESULTS

A total of 50 patients met the inclusion criteria. The prevalence of each structure was: agger nasi cell (89%), type 1 frontal cell (37%), type 2 frontal cell (19%), type 3 frontal cell (8%), type 4 frontal cell (0%), supraorbital ethmoid cell (62%), suprabullarcell (15%), frontal bullar cell (9%), interfrontal septal cell (14%), and recessus terminalis (22%).

CONCLUSIONS

This study describes frontal pneumatization in patients without a history of conditions that influence frontal pneumatization. The results characterize normal frontal recess/sinus pneumatization patterns.

MEG localization of rolandic spikes with respect to SI and SII cortices in benign rolandic epilepsy

The purpose of this study was to study the relationship between interictal spike sources and somatosensory cortices in benign rolandic epilepsy of childhood (BREC) using a whole-scalp neuromagnetometer. We recorded spontaneous magnetoencephalography (MEG) and EEG signals and cortical somatosensory-evoked magnetic fields (SEFs) to electric stimulation of the median nerve in 9 children with BREC. Interictal rolandic discharges (RDs) and SEFs were analyzed by equivalent current dipole (ECD) modeling. Based on the orientation and locations of corresponding ECDs, we compared generators of RDs with primary (SI) and second somatosensory cortices (SII). Our results showed that RDs and SII responses had similar ECD orientation on the magnetic field maps. The ECDs of RDs were localized 15.3 +/- 1.9 and 12.2 +/- 2.8 mm anterior to SI and SII, respectively. The spatial distance on average from the location of RDs to SII (21.9 +/- 1.6 mm) cortex was significantly shorter than to SI cortex (29.7 +/- 1.7 mm) (P<0.01, Wilcoxon signed-rank test). In conclusion, the cortical generators for RDs in patients with BREC are localized in the precentral motor cortex, closer to hand SII than to SI cortex.

Familial risk of allergic rhinitis and atopic dermatitis among Chinese families in Singapore

INTRODUCTION

This study aims to determine the familial risk of atopic dermatitis (AD) and allergic rhinitis (AR) in Chinese children.

MATERIALS AND METHODS

A cross-sectional study was conducted in a housing estate in Singapore. Data was collected using an interviewer-administered questionnaire. Participants included 257 Chinese families. Prevalence rate ratios (PRRs) and 95% confidence interval (CI) were calculated.

RESULTS

For AD in all children, an increasing trend was found with PRRs of 1.9 (95% CI, 0.3 to 11.8) and 1.5 (95% CI, 0.4 to 5.5) for only father and only mother affected, respectively, to 2.3 (95% CI, 0.4 to 13.7) for both parents affected. In AR, a PRR of 2.7 (95% CI, 1.8 to 3.9) and 2.2 (95% CI, 1.5 to 3.2) for only father and only mother affected, respectively, and 4.5 (95% CI, 3.3 to 6.1) for both affected was found. The PRR (2.2; 95% CI, 1.4 to 3.7) of the first child developing AR when paternal or maternal history was positive was similar. This rose to 3.4 (95% CI, 2.2 to 5.1) when both parents also had AR. The PRR of the second child developing AR was 3.9 (95% CI, 1.7 to 8.9) when the first child alone was positive for AR and 7.0 (95% CI, 3.5 to 13.9) when both parents and the eldest child had AR.

CONCLUSION

A positive family history increases the risk of developing AD and AR with increasing risk dependent on number of relatives affected. The second child's risk of AR is also associated with AR in the first child, suggesting mechanisms of incomplete penetrance.

Nasal deformity in neonates and young children

Pediatric nasal deformities comprise a broad range of congenital and acquired pathologies. The congenital deformities are rare and often require specific surgical interventions. The acquired deformities are more common, and in the majority of cases surgical intervention is not necessary. The decision to operate is based primarily on the extent of the functional impairment and the severity of the aesthetic deformity.

The mechanisms of neuronal death produced by mitochondrial toxin 3-nitropropionic acid: the roles of N-methyl-D-aspartate glutamate receptors and mitochondrial calcium overload

Previous studies showed that 3-nitropropionic acid, an irreversible inhibitor of succinate dehydrogenase, produced neuronal death secondary to perturbed intracellular calcium homeostasis. However, the response of intramitochondrial calcium ([Ca(2+)](m)) to 3-nitropropionic acid remains unknown. In this study, we investigated the roles of and relationships among [Ca(2+)](m) overload, mitochondrial reactive oxygen species, and mitochondrial membrane depolarization in 3-nitropropionic acid-induced neuronal death. Following 1 mM 3-nitropropionic acid treatment on primary rat neuronal cultures, there was a gradual increase of [Ca(2+)](m) beginning at 2-4 h post 3-nitropropionic acid application, and a twofold increase of mitochondrial reactive oxygen species at 4 h. These were followed by mitochondrial membrane depolarization at 6-8 h post-treatment. By inhibiting [Ca(2+)](m) uptake, Ruthenium Red attenuated the production of reactive oxygen species, and prevented the 3-nitropropionic acid-induced mitochondrial membrane depolarization and 70% of apoptotic neuronal death (P<0.001). Inhibition of caspase activation attenuated the elevation of [Ca(2+)](m) (P<0.001), indicating that caspase activation plays a role in the elevation of [Ca(2+)](m). MK-801, an antagonist of N-methyl-D-aspartate (NMDA) glutamate receptors, prevented 3-nitropropionic acid-induced [Ca(2+)](m) elevation, caspase-3 activation, mitochondrial depolarization, and neuronal death. We conclude that the activation of NMDA glutamate receptor contributes to mitochondrial alterations induced by 3-nitropropionic acid. Inhibition of its activation and [Ca(2+)](m) overload with subsequent mitochondrial membrane depolarization can therefore attenuate the neuronal death induced by 3-nitropropionic acid.

Early epileptic encephalopathy with suppression burst electroencephalographic pattern--an analysis of eight Taiwanese patients

Early epileptic encephalopathy with suppression burst (SB) comprises two distinct epileptic syndromes, early infantile epileptic encephalopathy (EIEE) and early myoclonic encephalopathy (EME). We reviewed etiologies, neurological outcome and clinico-electroencephalographic features of EIEE and EME. Chart records of early epileptic encephalopathy with SB from January 1997 to December 2000 were reviewed. These cases fulfilled the diagnostic criteria of EIEE and EME. Totally eight patients (four females, four males) were enrolled. They consisted of three cases of EIEE and five cases of EME. The follow-up periods ranged from 6 to 30 months. For EIEE, two cases had migrational disorders, and one was cryptogenic; for EME, three cases had non-ketotic hyperglycinemia (NKH), one was pyridoxine dependency and one was cryptogenic. The main initial seizure patterns were tonic spasms in EIEE, and were erratic myoclonus in EME. The age of seizure onset ranged from 26 h to 5 days after birth for EIEE, and 2 h to 7 days of life for EME. The SB pattern in the electroencephalography (EEG) was noted mainly during sleep state in EME, but in both awake and sleep states in EIEE. Asymmetric SB pattern and background activities in EEG were found in migrational disorders. The EEG in all cases of EIEE changed to hypsarrhythmia at 4-6 months of age. In EME, only the EEG in cases of NKH evolved to hypsarrhythmia. Response to anti-convulsants was generally poor. All had severe psychomotor retardation. Although EIEE and EME share several common features, differences in terms of seizure seminology and evolution, EEG patterns and etiologies still exist.

Human papilloma virus type 16 E7 genes protect astrocytes against apoptotic and necrotic death induced by hydrogen peroxide

Hydrogen peroxide is considered to be a dose- and time-dependent mediator in apoptotic and necrotic death. In this study, we examined the signaling of the E6 and E7 proteins with respect to apoptosis or necrosis after H2O2 injury using an in vitro model with overexpressed E6 or E7 genes. For this purpose, the E6 and E7 gene expressing astrocytes were exposed to 10 micromole and 200 micromole H2O2 solutions. Twenty- four hours after treatment with the lower dosage(10 micromole H2O2), control, E6-expressing cells suffered about 45% injury and LXSN-expressing cells decreased by 67% as assessed by LDH release. However, E7-expressing cells showed less injury, resulting in 20-30% of LDH release. Astrocytes expressing E6, E7, LXSN and mock-infected cells showed a typical apoptotic death pattern on the DNA gel after treatment with a low-dose of H2O2 (10 micromole), however they died from necrotic death after a high-dose (200 micromole) H2O2. Overexpression of HPV-E7 genes protected the cells from apoptotic death after a low-dose of H2O2 and from necrotic death after a high-dose of H2O2, while the overexpression of E6 genes from the necrotic death. E7 expressing astrocytes showed higher catalase activity and the levels of E2F protein surged more than 100-folds compared with the control astrocytes. We believe that the activity of E7 protein to protect astrocytes from H2O2 injury was at least partly due to increased catalase, a scavenger protein.

Selective and biphasic effect of the membrane lipid peroxidation product 4-hydroxy-2,3-nonenal on N-methyl-D-aspartate channels

Increased oxyradical production and membrane lipid peroxidation occur in neurons under physiological conditions and in neurodegenerative disorders. Lipid peroxidation can alter synaptic plasticity and may increase the vulnerability of neurons to excitotoxicity, but the underlying mechanisms are unknown. We report that 4-hydroxy-2,3-nonenal (4HN), an aldehyde product of lipid peroxidation, exerts a biphasic effect on NMDA-induced current in cultured rat hippocampal neurons with current being increased during the first 2 h and decreased after 6 h. Similarly, 4HN causes an early increase and a delayed decrease in NMDA-induced elevation of intracellular Ca2+ levels. In contrast, 4HN affects neither the ion current nor the Ca2+ response to alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA). The initial enhancement of NMDA-induced current is associated with increased phosphorylation of the NR1 receptor subunit, whereas the delayed suppression of current is associated with cellular ATP depletion and mitochondrial membrane depolarization. Cell death induced by 4HN is attenuated by an NMDA receptor antagonist, but not by an AMPA receptor antagonist. A secreted form of amyloid precursor protein, previously shown to protect neurons against oxidative and excitotoxic insults, prevented each of the effects of 4HN including the early and late changes in NMDA current, delayed ATP depletion, and cell death. These findings show that the membrane lipid peroxidation product 4HN can modulate NMDA channel activity, suggesting a role for this aldehyde in physiological and pathophysiological responses of neurons to oxidative stress.

The kinetics of catalytic incineration of C2H5SH and (CH3)2S2 over a Pt/Al2O3 catalyst

Catalytic incineration is one of the cost-effective technologies to solve the troublesome VOCs. However, some sulfur containing VOCs, such as ethyl mercaptan and dimethyl disulfide, may deactivate the Pt catalyst that is commonly used in the catalytic incineration process. The catalytic incineration of these compounds over a Pt/Al2O3 catalyst was carried out in a bench scale catalytic incinerator. Three kinetic models, such as power-rate law, Mars and Van Krevelen model, and Langmuir-Hinshelwood model were used to analyze the results. A differential reactor design was used for best fit of kinetic models in this study. The results show that the Langmuir-Hinshelwood model is feasible to describe the catalytic incineration of both C2H5SH and (CH3)2S2. This suggests that the chemical adsorption of O2 molecule is important in the process of catalytic incineration of C2H5SH and (CH3)2S2.

The catalytic incineration of (CH3)2S and its mixture with CH(3)SH over a Pt/Al(2)O(3) catalyst

Catalytic incineration is one of the cost-effective technologies to solve the troublesome volatile organic compounds (VOCs). However, some sulfur containing VOCs, such as dimethyl sulfide, may deactivate the Pt catalyst that is commonly used in the catalytic incineration process. This paper provides information on the poisoning effect of (CH3)2S. The catalytic incineration of (CH3)2S, typically emitted from the petrochemical industry, over a Pt/Al(2)O(3) fixed bed catalytic reactor was studied. The effects of operating parameters including inlet temperature, space velocity, (CH3)2S concentration, O2 concentration and catalyst size were characterized. Catalytic incineration on a mixture of (CH3)2S with CH(3)SH was also tested. The results show that the conversions of (CH3)2S increase as the inlet temperature increases and the space velocity decreases. The higher the (CH3)2S concentration is, the lower its conversion is. The O2 concentration has a positive effect on the conversion of (CH3)2S. (CH3)2S has a poisoning effect on the Pt/Al(2)O(3) catalyst, especially at lower temperatures. The conversion of (CH3)2S is significantly suppressed by the existence of CH(3)SH.

Neurocutaneous melanosis with epilepsy: report of one case

Neurocutaneous melanosis is a rare congenital syndrome characterized by the association of large or multiple congenital melanocytic nevi and benign or malignant melanotic tumors in the central nervous system. Patients with neurocutaneous melanosis usually have neurological symptoms early in life that progress rapidly due to the development of increased intracranial pressure or malignant melanoma. We report a 2-month-old female infant with multiple congenital melanocytic nevi and frequent seizure attacks. Magnetic resonance imaging of the brain demonstrated several regions compatible with melanotic deposits. During follow-up for one year, she had normal development and was seizure-free under the treatment of phenobarbital and valproic acid. We suggest that infants with large or multiple congenital melanocytic nevi should receive regular clinical check-up and brain imaging to exclude the possibility of central nervous system lesions.

Studies on the changes of c-fos protein in spinal cord and neurotransmitter in dorsal root ganglion of the rat with an experimental peripheral neuropathy

Animal models for human chronic pain syndromes have been developed and widely used for pain research. One of these neuropathic pain models by Kim and Chung (1992) has many advantages for operation and pain elicitation. In this neuropathic model we have examined the c-fos protein, substance P, CGRP immunoreactivity in dorsal root ganglia and dorsal horn. 50 Sprague-Dawley rats were used for this study. L5 and L6 spinal nerves were ligated tightly to produce the neuropathic pain model. After 2, 4, 8, 16, and 24 hours and 1 week of surgery, rats were anesthetized and sacrificed by perfusion. After confirmation of the roots transected by the surgery, the L5 and L6 dorsal root ganglions and spinal cord were removed and processed for immunohistochemistry. All tissue sections were immunohistochemically stained for substance P, CGRP and c-fos using the peroxidase-antiperoxidase (PAP) method. The number of immunostained substance P and CGRP dorsal root ganglion cells and c-fos immunoreactive dorsal horn cells were counted and analyzed statistically with Mann-Whitney U test. The results are as follows. The number of c-fos protein immunoreactive neurons in the superficial layer of dorsal horn were increased markedly 2 hours after operation, and gradually decreased to normal level 1 week after operation. The number of c-fos protein immunoreactive neurons in the deep layer of the dorsal horn gradually increased to a peak 24 hours after operation, then decreased to the normal level 1 week after operation. The number of substance P and CGRP immunoreactive L5 and L6 dorsal root ganglion neurons were decreased markedly 1 week after the pain model operation. In conclusion, after neuropathic pain model operation, c-fos proteins were immediately expressed in the superficial layer of spinal dorsal horn, thereafter c-fos proteins in the deep layer of spinal dorsal horn were expressed. CGRP and substance P immunoreactive neurons in DRG were decreased markedly 1 week after neuropathic pain model operation. These decrements do not coincide with the other chronic pain models, which show great increases in these pain transmitting substances. Therefore, the relationship between pain and c-fos, SP and CGRP should be investigated further.

Coronary artery fistulas: long-term results of surgical correction

BACKGROUND

Opinions vary as to whether operation should be offered patients with coronary artery fistula, particularly to those who are asymptomatic. Published studies lacked long-term follow-up data.

METHODS

We studied 41 patients with coronary artery fistula operated in our unit in the past 30 years with restudies including coronary angiograms in those who agreed to the investigation.

RESULTS

There was no operative mortality and operative morbidity was low. The mean duration of follow-up was 9.1 years and 96.9% of the patients were asymptomatic. Twenty-one patients had a coronary angiogram. The native coronary artery either remained dilated and tortuous, or more frequently had thromboses with a short proximal stump. (None of these patients had evidence of myocardial ischemia.) Four patients had demonstrable recurrence fistula but without hemodynamic disturbance.

CONCLUSIONS

We advocate operation for all patients with coronary artery fistulas and demonstrable shunting in view of minimal operative risks. Small asymptomatic fistulas without demonstrable shunting should be left alone. The relatively high incidence of residual or recurrent fistula makes long-term follow-up mandatory.

IFN-gamma production by Th1 cells generated from naive CD4+ T cells exposed to norepinephrine

During activation in vivo, naive CD4(+) T cells are exposed to various endogenous ligands, such as cytokines and the neurotransmitter norepinephrine (NE). To determine whether NE affects naive T cell differentiation, we used naive CD4(+) T cells sort-purified from either BALB/c or DO11.10 TCR-transgenic mouse spleens and activated these cells with either anti-CD3/anti-CD28 mAbs or APC and OVA(323-329) peptide, respectively, under Th1-promoting conditions. RT-PCR and functional assays using selective adrenergic receptor (AR) subtype antagonists showed that naive CD4(+) T cells expressed only the beta 2AR subtype to bind NE and that stimulation of this receptor generated Th1 cells that produced 2- to 4-fold more IFN-gamma. This increase was due to more IFN-gamma produced per cell upon restimulation instead of more IFN-gamma-secreting cells, as determined by IFN-gamma-specific immunofluorescence and enzyme-linked immunospot. In contrast, Th1 cell differentiation was unaffected when naive T cells were exposed to NE and activated either in the presence of a neutralizing anti-IL-12 mAb or by APC from IL-12-deficient mice. Moreover, the addition of IL-12 to the IL-12-deficient APC cultures restored the ability of NE to increase Th1 differentiation. Taken together, these results indicate that a possible link may exist between the signaling pathways used by NE and IL-12 to increase naive CD4(+) T cell differentiation to a Th1 cell.

Cytokine production by naive and primary effector CD4+ T cells exposed to norepinephrine

We recently showed that clones of Th1 cells, but not Th2 cells, expressed a functional beta-2-adrenergic receptor (beta2AR) and that either norepinephrine or the beta2AR agonist terbutaline stimulated this receptor to modulate the level of Th1 cytokines produced. In the present study, we show that norepinephrine and terbutaline stimulate the beta2AR to decrease the level of IL-2 produced by freshly isolated murine splenic naive CD4+ T cells from either Balb/C or DO11.10 transgenic mice and activated polyclonally with anti-CD3 and anti-CD28 mAbs. In contrast, the level of cytokines produced by primary effector Th1 and Th2 cells were unaffected when norepinephrine, terbutaline, or cAMP analogs were added at the time of restimulation. These results suggest that a diversity exists among CD4+ T-cell subsets with respect to the level of adrenergic receptor expression, responsiveness to cAMP, stage of cell differentiation, or a combination of the above.

Immunogenicity of a foreign peptide expressed within a capsid protein of an attenuated coxsackievirus

The immunogenicity of soluble peptides can be improved by expression within recombinant microorganisms. The immunogenicity of a peptide expressed within a capsid protein of an attenuated coxsackievirus B4 was evaluated. The insertion site was chosen based on its antigenic structure. A foreign peptide was inserted into a region of the VP1 capsid protein that was identified as a T helper cell epitope. A recombinant virus containing ten amino acids of ovalbumin sequence was genetically stable and retained the biological and physical characteristics of the parental virus. The recombinant was able to elicit a T helper cell response against ovalbumin sequences. This study shows, for the first time, that coxsackievirus can be used as an expression vector and that insertion of heterologous peptides into an immunogenic region is a viable strategy for inducing T helper cell responses against foreign sequences. The implications of this work are that the attenuated coxsackievirus variant may be useful as a vaccine vector for expressing T helper cell epitopes that are important in inducing protective immunity.

Fat intake in Hong Kong Chinese children

The people of Hong Kong are experiencing a transition in dietary practices and lifestyle that can be observed in the fat intakes of Hong Kong children as compared with those of their counterparts on mainland China. The studies described here include 1) a longitudinal and observational dietary survey beginning with a cohort of 174 newborns and concluding with 124 children at age 7 y; 2) a biochemical study of serum lipids in relation to dietary fat intake at age 7 y; 3) a chemical fatty acid analysis and comparison of duplicate meals collected from 20 Hong Kong and 20 mainland Chinese children at age 7 y; 4) a dietary assessment of 52 lactoovovegetarian children aged 4-14 y; and 5) a comparison of the growth of all subjects with US National Center for Health Statistics standards. About 30% of the total daily energy intake of Hong Kong Chinese children aged 1-7 y was contributed by fat-much more than that in the traditional Chinese diet. Growth of the children was not impaired, including that of children on the mainland and of those lactoovovegetarians in Hong Kong whose fat intakes were lower. Mean serum cholesterol of Hong Kong Chinese children at age 7 y was 4.59 mmol/L, significantly higher than that of their counterparts on the mainland, 4.16 mmol/L. Foods consumed in Hong Kong had a significantly lower ratio of 18:2 to 14:0. Nutritional deficiency was uncommon. Chinese children in Hong Kong had a dietary fat intake that was both quantitatively and qualitatively different from the traditional Chinese diet.

Acute hemiplegia associated with herpes zoster infection in children: report of one case

Herpes zoster infection has been rarely reported to cause angiitis of the central nervous system in children. We describe a 4-year, 8-month-old female with acute hemiplegia and central facial palsy 6 weeks after she had had zoster ophthalmicus. The findings of magnetic resonance angiography, the clinical picture, and a preceding history of herpes zoster ophthalmicus suggested zoster vasculitis. Herpes zoster vasculitis is thus another consideration when examining a child with acute hemiplegia and a recent herpes zoster infection.

Pepsin-mediated processing of the cytoplasmic histone H2A to strong antimicrobial peptide buforin I

The intestinal epithelium forms a first line of innate host defense by secretion of proteins with antimicrobial activity against microbial infection. Despite the extensive studies on the antimicrobial host defense in many gastrointestinal tracts, little is known about the antimicrobial defense system of the stomach. The potent antimicrobial peptide buforin I, consisting of 39 aa, was isolated recently from the stomach tissue of an Asian toad, Bufo bufo gargarizans. In this study we examined the mechanism of buforin I production in toad stomach tissue. Buforin I is produced by the action of pepsin isozymes, named pepsin Ca and Cb, cleaving the Tyr39-Ala40 bond of histone H2A. Immunohistochemical analysis revealed that buforin I is present extracellularly on the mucosal surface, and unacetylated histone H2A, a precursor of buforin I, is localized in the cytoplasm of gastric gland cells. Furthermore, Western blot analysis showed that buforin I is also present in the gastric fluids, and immunoelectron microscopy detected localization of the unacetylated histone H2A in the cytoplasmic granules of gastric gland cells. The distinct subcellular distribution of the unacetylated histone H2A and the detection of the unacetylated buforin I both on the mucosal surface and in the lumen suggest that buforin I is produced from the cytoplasmic unacetylated histone H2A secreted into the gastric lumen and subsequently processed by pepsins. Our results indicate that buforin I along with pepsins in the vertebrate stomach may contribute to the innate host defense of the stomach against invading microorganisms.

Temporal changes of cerebral metabolites and striatal lesions in acute 3-nitropropionic acid intoxication in the rat

To investigate the mechanisms of neuronal death in neurodegeneration, in vivo localized proton magnetic resonance spectroscopy ((1)H-MRS) and diffusion-weighted MRI (DWI) were used to evaluate temporal changes in rat striata after administration of 3-nitropropionic acid. It was found that N-acetylaspartate (NAA) reduction, with nearly simultaneous evidence of striatal lesions in DWI, was preceded by a significant and progressive increase of acetate. Shortly before the NAA levels decreased to the lowest point, acetate levels peaked and began to gradually decline toward the control levels. These results suggest that acetate increase may arise from fatty acid degradation, inhibition of succinate dehydrogenase and possible NAA hydrolysis. The elevated acetate may provide a source of acetyl group for membrane repair during excitotoxic brain injury. Magn Reson Med 44:29-34, 2000.

Mitochondrial cytopathy combined with Fanconi's syndrome

Severe muscle weakness in Fanconi's syndrome is rarely the result of mitochondrial cytopathy. We describe a rare case of a 9-year-old male with early onset of Fanconi's syndrome. He developed severe proximal muscle weakness exacerbated by hypokalemia and hypophosphatemia in childhood. The muscle biopsy revealed increased accumulation of abnormal mitochondria and fat droplets in histochemical stains and electron microscopy. Mitochondrial cytopathy cannot be excluded in Fanconi's syndrome with late onset of muscular impairment. Long-term follow-up of his clinical course is suggested to understand the natural history of this unusual case.

Neonatal administration of IL-12 enhances the protective efficacy of antiviral vaccines

Neonates are highly susceptible to infectious agents and are known to display polarized expression of Th2-like cytokines and Abs. This neonatal immune bias has important implications for the development of vaccine strategies, particularly against viral infections. We now report that coadministration of IL-12 and an influenza subunit vaccine at birth enhances the protective efficacy of antiviral vaccination. Immunization and treatment with IL-12 within 24 h of birth resulted in elevated expression of IFN-gamma, IL-10, and IL-15 mRNA in the spleens of newborn mice compared with animals exposed to vaccine only. In addition, these animals showed dramatic increases in IFN-gamma-, IL-2-, and IL-4-secreting cells, and in IgG2a Ab levels upon adult challenge compared with mice primed with vaccine alone. Most importantly, animals vaccinated and simultaneously treated with IL-12 at birth displayed enhanced survival after lethal challenge with infectious influenza virus as adults compared with infected animals that had been primed with vaccine alone. This augmented protection required B cells and could be transferred to naive mice by immune serum. Collectively, these results provide evidence that administration of IL-12 to neonates induces a Th1-like response in newborns and elicits protective antiviral immune memory.

Growth and nutrition of Hong Kong children aged 0-7 years

OBJECTIVE

To study the early dietary practices in relation to growth of Hong Kong children from birth to 7 years.

METHODOLOGY

One hundred and seventy-three full-term Hong Kong Chinese babies were recruited at birth and were followed up for anthropometric measurements using standardized methods and dietary assessment using a combination of dietary history, 24 h recall and food frequency. At 7 years, 125 children remained in the study.

RESULTS

Mean (SD) birthweight was 3.3 (0.38) kg for boys and 3.1 (0.38) kg for girls. Mean (SD) weight at 7 years was 22.4 (4.2) kg for boys and 21.1 (3.7) kg for girls, and mean (SD) height was 120.3 (4.8) cm for boys and 119.8 (5.1) cm for girls. Hong Kong children were lighter and shorter than Australian children and the National Centre for Health Statistics (NCHS) references, but the magnitude is less than one standard deviation score. Mean weight and height of Hong Kong children were lower compared to Caucasian and Beijing children, with more obvious differences between 1 and 5 years. At 1 year, mean (SD) daily energy intake was 98 (24) kcal/kg/day for boys and 100 (26) kcal/kg/day for girls. By 7 years, it decreased to 82 (18) kcal/kg/day for boys and 73 (22) kcal/kg/day for girls. Between 2 to 4 years of age the energy intake of studied children were slightly lower than the Australian and Finnish children, but the protein intake was higher. Percentage of fat contributing to total daily energy intake was lower throughout at a level of 30%. Such differences in diet reflect a lower consumption of milk fat, higher consumption of meat and lower level of physical activity in Hong Kong children. Intakes of calcium, iron and vitamin C all reached 60% or above of US recommended daily allowance.

CONCLUSIONS

The smaller body build of Chinese compared to Caucasians cannot be explained by dietary differences. The diet of Hong Kong children is changing to one which is more Westernized with a higher consumption of animal products.

Neuroprotective effect of lamotrigine and MK-801 on rat brain lesions induced by 3-nitropropionic acid: evaluation by magnetic resonance imaging and in vivo proton magnetic resonance spectroscopy

Magnetic resonance imaging and in vivo proton magnetic resonance spectroscopy were used to evaluate the therapeutic effect of lamotrigine and MK-801 on rat brain lesions induced by 3-nitropropionic acid. Systemic administration of 3-nitropropionic acid (15 mg/kg per day) to two-month-old Sprague-Dawley rats (n = 10 for each group) for five consecutive days induced selective striatal and hippocampal lesions and specific behavioral change. Pretreatment with lamotrigine (10 mg/kg or 20 mg/kg per day) or MK-801 (2 mg/kg per day) attenuated the lesions and behavioral change. There were no significant differences in T2 values of the striatum and hippocampus among rats pretreated with MK-801, lamotrigine (20 mg/kg) and sham controls. Significant elevations of succinate/creatine and lactate/creatine ratios and decreases of N-acetylaspartate/creatine and choline/creatine ratios were observed after 3-nitropropionic acid injections (P < 0.001). The changes were nearly prevented after pretreatment with lamotrigine (20 mg/kg). However, the N-acetylaspartate/creatine in rats pretreated with lamotrigine (10 mg/kg) (P < 0.01) and MK-801 (P < 0.05) still showed significant reduction as compared with sham controls. Thus we conclude that both lamotrigine and MK-801 are effective in attenuation of brain lesions induced by 3-nitropropionic acid. A higher dose of lamotrigine provides a better neuroprotective effect than MK-801. With a better therapeutic effect and fewer side effects, lamotrigine is more promising for potential clinical application.

Congenital intracranial teratoma

Congenital intracranial teratoma is a rare disease. A fetus with a congenital intracranial teratoma presenting with a disproportionately enlarged head at 27 weeks gestation is presented. Prenatal ultrasonography and fetal magnetic resonance imaging demonstrate a huge, heterogenous intracranial mass in the left supratentorial region, with the left cerebral hemisphere being compressed and flattened. The infant died of respiratory failure within 24 hours of birth at 28 weeks gestation. On postmortem examination the histologic report revealed an immature teratoma. Fetal MRI is helpful in the prenatal diagnosis and evaluation of intracranial tumor.

Persistent hypertransaminasemia as the presenting findings of muscular dystrophy in childhood

Prolonged elevation of the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) is often attributed to hepatic diseases. However, these enzymes are also present in a variety of extrahepatic tissues, including skeletal muscle. Five children (all boys) were referred to the pediatric department of the National Taiwan University Hospital because of persistent elevation of serum aminotransferase activities. The ages of these children were between 4 months and 5.5 years. The neurological findings were all not remarkable. The initial ALT and AST values were 114-581 U/L and 183-700 U/L, respectively. Serum creatine kinase was checked first after 0 to 30 months follow-up and found to be markedly elevated (range, 10,557 U/L to 62,508 U/L). Muscle biopsies in the five cases all showed degenerating and regenerating myofibers with interstitial fibrosis. In Cases 3, 4 and 5, complete absence of dystrophin immunoreactivity was found. Genetic studies showed deletions in the DMD gene (exons 45-48 in case 2 and 49-50 in case 4). This experience indicates that occult muscle diseases should be taken into account in patients with unexplained long-lasting hypertransaminasemia and therefore measurement of serum creatine kinase activity and muscle biopsy should be done early for the correct diagnosis of muscular dystrophy.

Power Doppler ultrasound imaging in neonatal cerebral venous sinus thrombosis

Neonatal sinus thrombosis is a rare occurrence in sick neonates. Because of its nonspecific manifestations, the incidence is underestimated. This disease may not be demonstrated by conventional color Doppler and is diagnosed by computed tomography or magnetic resonance imaging. The authors report a neonate with neonatal sinus thrombosis diagnosed by power Doppler and suggest that the technique may be used as a less expensive and more available screening and follow-up method in high-risk neonates.

Decreased cerebrospinal fluid absorption during abdominal insufflation

BACKGROUND

Intracranial pressure (ICP) is known to rise during induced CO(2) pneumoperitoneum. This rise correlates with an increase in inferior vena caval pressure; therefore, it is probably associated with increased pressure in the lumbar venous plexus. Branches of this plexus communicate with arachnoid villi in the lumbar cistern and the dural sleeves of spinal nerve roots-areas where cerebrospinal fluid (CSF) absorption to normally takes place. The increased venous pressure in this area may impede CSF absorption. Because CSF is produced at a constant rate, decreased absorption will increase ICP. We hypothesized that increased ICP occurring during abdominal insufflation is due, at least in part, to decreased absorption of CSF. The purpose of this study is to show that CSF absorption is inhibited during abdominal insufflation.

METHODS

After appropriate approval was obtained, 16 domestic swine were anesthetized and injected into the CSF with 100 microcuries (microCu) of I(131) radioactive iodinated human serum albumin (RISA) in 2 ml of normal saline. Eight subjects underwent CO(2) abdominal insufflation to 15 mmHg and were maintained for 4 h. A control group did not undergo insufflation. Blood levels of RISA were measured over a 4-h period to determine the rate of CSF absorption.

RESULTS

Blood levels of RISA increased at a slower rate in the subjects undergoing abdominal insufflation than in the control group. The mean change over 2 h in the insufflated group was 15% compared to 34% in the control group (p = 0.02). This difference indicates decreased absorption of CSF in the insufflated group.

CONCLUSIONS

These results demonstrate decreased absorption of CSF during abdominal insufflation and support the hypothesis that the increase in ICP pressure occurring during abdominal insufflation is caused, at least in part, by decreased absorption of CSF in the region of the lumbar cistern and the dural sleeves of spinal nerve roots.

3-D power Doppler cerebral angiography in neonates and young infants: comparison with 2-D power Doppler angiography

The aims of this study were to evaluate the ability of 3-dimensional (3-D) power Doppler angiography (3DPDA) to depict the intracranial vasculature in infants, to compare with 2-D power Doppler ultrasonography (2DPDU), and to explore the potential clinical applications of this procedure in young infants with brain disorders. We performed 3DPDA in 27 infants. 2DPDU were completed in both sagittal and coronal directions in 12 of these patients. In the other 15, only right sagittal plane images were available for comparison. Using a grading system and with only vessels with more than half of the length demonstrated included for comparison, we compared the Doppler signals of major vessels. 3DPDA could have good visualization in more than 60% of the internal carotid artery, ophthalmic artery, pericallosal artery, callosomarginal artery, internal cerebral vein, vein of Galen, and straight sinus in the sagittal plane. 3DPDA also could have good demonstration in about 50% of basilar artery in coronal plane, and posterior communicating artery, posterior cerebral artery, and lenticulostriate artery in sagittal plane. 3DPDA was better than 2DPDU in demonstrating all the major intracranial vessels in different planes, except the anterior communicating artery. In the anterior communicating artery, neither can demonstrate more than 30%.

Axial and peripheral bone mineral acquisition: a 3-year longitudinal study in Chinese adolescents

We performed a 3-year longitudinal study of a group of 179 healthy Chinese adolescents (92 boys and 87 girls) aged from 12 to 16 years to determine the effects of puberty, physical activity, physical fitness, and calcium intake on the acquisition of bone mass. At yearly intervals for 3 consecutive years we recorded nutrition, calcium intake and anthropometric measurements, and assessed pubertal status according to Tanner. Bone mass of the lumbar spine was determined by dual-energy X-ray absorptiometry and radial bone mass by single-photon absorptiometry. Physical fitness and level of physical activity were assessed and muscle strength and power determined by isokinetic testing. Peripheral bone mass correlated with axial skeleton bone mass. Age, pubertal staging, physical fitness and muscle strength were significantly associated with bone mass increments on cross-sectional univariate and regression analysis. Longitudinal regression analysis showed that the most important factor affecting bone mass accretion in adolescents in both sexes was their pubertal stage. In boys, bone mass increment throughout the study was greater in children who were already in the advanced pubertal stages on entering the study than in those who started puberty in year 2 or 3 of the study. The percentage change in bone mineral content of the forearm and in bone mineral density of the lumbar spine was greater than 25% in the advanced pubertal group as compared to around 20% in the less mature group. For girls, the reverse was true. The increment of bone mass during the study period was significantly greater in those who presented in the earlier pubertal stages than in those who were at the more advanced stage of puberty on entry into the study. There was no significant effect of calcium intake and physical activities on the bone mass accretion.

CONCLUSION

In Chinese adolescents, bone mineral accretion at adolescence is not influenced by exercise, level of physical fitness and calcium intake. In both sexes, and especially in girls, to optimally increase bone mass, regular physical exercise programmes should be instituted well before the onset of puberty rather than at or after it. Once puberty starts, these interventions may have no or only limited effect.

T cells contribute to disease severity during coxsackievirus B4 infection

By using a model of coxsackievirus B4-induced disease, the question of whether tissue damage is due to the virus or to immune-mediated mechanisms was addressed. Both viral replication and T-cell function were implicated in contributing to the severity of disease. Three stages (I to III) of disease, which correspond to periods of high viral titers, low viral titers, and no infectious virus, have been identified. Stage I disease is considered to be primarily the result of viral replication. Immunopathological mechanisms appear to contribute to the severity of stage II and III disease. To investigate the role of T cells in contributing to the severity of disease, viral infection in CD8 knockout (ko) mice and CD4 ko mice was analyzed. CD8 T-cell responses appear to be beneficial during early, viral disease but detrimental in later disease when viral titers are diminishing. CD4 ko mice, unlike the parental strain, survived infection. Viral replication was lower in the CD4 ko mice. Was survival due to decreased viral replication or to the lack of T-helper-cell function? To investigate further the role of T helper cells in contributing to tissue damage, viral infection in two additional ko strains (interleukin-4 [IL-4] ko and gamma interferon ko strains) was examined. A clear correlation between viral replication and the outcome of infection was not observed. The absence of IL-4, which may influence T-helper-cell subset development, was advantageous during early viral disease but deleterious in later disease. The results suggest that T-cell-mediated immunity is both beneficial and detrimental during coxsackievirus B4 infection.

Vocal cord paralysis and hypoventilation in a patient with suspected Leigh disease

The authors report the case of a 16-month-old male with suspected Leigh disease, which was diagnosed on the basis of the clinical manifestations, abnormal lactate stimulation test, proton magnetic resonance spectroscopy, and neuroradiologic findings. Progressive stridor resulting from bilateral vocal cord paralysis and hypoventilation was evident. The authors suggest that for infants or children who exhibit vocal cord paralysis, mitochondrial disorders, such as Leigh disease, should be considered.

A non-fatal impalement injury of the thorax

Impalement is an uncommon injury with only occasional reports in the literature. There are even fewer reports of impalement injuries limited to the thorax. We report herein the case of a 24-year-old man who survived impalement injury of the left side of the thorax with a steel rod while working at a construction site. The great vessels of the thorax were spared but the second thoracic vertebra was fractured resulting in complete paralysis of the left lower limb. The precise nature and extent of the injury were determined pre-operatively by computed tomography and aortography. The important principles of surgical management contributing to the successful outcome are described, these being minimal manipulation of the impalement object before and during transport, careful pre-operative planning and a multidisciplinary approach.

Repair of ruptured sinus of valsalva aneurysm: determinants of long-term survival

BACKGROUND

Ruptured sinus of Valsalva aneurysm is a rare cardiac anomaly and long-term survival after surgical treatment is not well established. This study was designed to investigate the determinants of long-term survival after repair of ruptured sinus of Valsalva aneurysm.

METHODS

From April 1978 to April 1996, 53 patients underwent operation for ruptured sinus of Valsalva aneurysm. The incidence among our cardiac surgical population was 0.56%. Long-term survival was investigated in 46 patients (13 to 65 years) who survived the operation, with 96.2% follow-up completeness (mean+/-standard deviation, 6.5+/-4.9 years; maximum, 17.2 years), by univariate and multivariate analyses.

RESULTS

There was no early operative death and no recurrence after the initial repair. Actuarial survival was 83.8%+/-8.4% at 15 years. Reoperation, aneurysm draining into the left ventricle, aortic prosthetic dehiscence, bacterial endocarditis, and aortic cross-clamp time (<70 minutes) were significant factors in long-term survival (p < 0.05). Multivariate analysis revealed that only aortic prosthesis dehiscence was the significant factor influencing late survival (p = 0.0001).

CONCLUSIONS

Surgical treatment for ruptured sinus of Valsalva aneurysm is safe and has satisfactory results. Aortic prosthesis dehiscence is the independent determinant for long-term survival. Other factors including bacterial endocarditis, concomitant ventricular septal defect repair, and aortic valve replacement did not independently influence long-term survival.

Self-restricted dual receptor memory T cells

Enhanced immune responses during secondary exposure to Ag result from the development of memory cells. In the present report we show that stimulation through one receptor on dual receptor CD4 cells can promote the generation of T cells capable of giving a memory response through the second receptor, even though the cells had not been previously exposed to the Ag recognized by the second receptor. Cloned cells generated from dual receptor memory T cells proliferated and secreted the same lymphokines after stimulation with either Ag. Independent recognition of both Ags by distinct TCRs was shown by production of variants that had lost either Ag specificity along with the corresponding TCR. Recognition of both Ags is MHC restricted, since the cells recognize Ag presented by self, but not non-self, MHC class II molecules. These results raise the possibility that one potential mechanism of maintaining specific memory to a given Ag is through stimulation by an unrelated Ag via the second TCR.

Risk factors for development of acute renal failure (ARF) requiring dialysis in patients undergoing cardiac surgery

Acute renal failure (ARF) is one of the major complications after cardiopulmonary bypass for open heart operations. The present study was undertaken to identify the risk factors for the development of ARF following cardiopulmonary bypass (CPB). Four hundred and forty-seven consecutive patients who underwent open heart procedures from July 1994 to June 1995 were analyzed retrospectively. Their mean age was 55.6 +/- 14.2 (SD) years (range, 18 to 80). Dialysis was instituted whenever a patient exhibited inadequate urine output (<0.5 mL/kg/hr) for 2 to 3 hours despite correction of hemodynamic status and diuretic therapy, especially if fluid overload, hyperkalemia, or metabolic acidosis were also present. Twenty variables were analyzed by univariate analysis; these included nine preoperative variables--age, sex, hypertension, atherosclerosis, diabetes mellitus, left ventricular end-diastolic dimension (LVEDD) >5 cm, preoperative congestive heart failure, renal insufficiency (serum creatinine > or =130 micromol/L on two occasions), and sepsis--10 intraoperative variables--duration of CPB, redo procedures, emergency surgery, use of intraaortic balloon pump (IABP) in operating room, use of gentamicin, use of ceftriaxone, use of sulbactam/ampicillin, requirement of deep hypothermic circulatory arrest, duration of low mean perfusion pressure (mean pressure <50 mmHg for more than 30 minutes), operation on multiple valves--and one postoperative variable--significant hypotension (systolic blood pressure less than 90 mmHg for more than 1 hour). Significant variables or the variables having a trend (p<0.1) to be associated with ARF were included in stepwise multiple logistic regression analyses. Three regression analyses were performed separately. The incidence of ARF requiring dialysis in the study period was 15.0%. Significant risk factors for whole group of patients (regression I) were preoperative renal insufficiency (p<0.0001), postoperative hypotension (p<0.0001), cardiopulmonary bypass time more than 140 min (p<0.005), preoperative congestive heart failure (p<0.01), and history of diabetes mellitus (p<0.01). The risk factors in the valve group of patients (regression II) were preoperative renal insufficiency (p<0.0001) and postoperative hypotension (p<0.05). Risk factors in the CABG patients (regression III) were postoperative hypotension (p=0.0001), CPB time more than 140 min (p<0.05), preoperative renal insufficiency (p<0.05), and age (p<0.05). The authors conclude that preoperative renal insufficiency and postoperative hypotension are the most important independent risk factors for ARF in postcardiac surgical patients. In addition, CPB time greater than 140 minutes and old age are also independent risk factors for ARF in CABG patients. CPB time more than 140 minutes, history of diabetes mellitus, and preoperative congestive heart failure are independent risk factors for development of ARF in our total group of patients. These findings may have important clinical implications in the prevention of ARF in postcardiac surgical patients.