Endoscopic pediatric plastic surgery

Although the advent of endoscopic technology is expanding the fields of reconstructive and aesthetic surgery in adults, there have been to date no reports of its use in the pediatric population. Because of its minimally invasive nature, yet wide range of exposure, endoscopic techniques have much appeal in this age group. Herein we present our initial experience with endoscopic pediatric plastic surgery. From February 1995 to December 1995, 41 patients were treated utilizing 5-mm and 10-mm endoscopes at Scottish Rite Children's Medical Center, Atlanta, GA. There were 19 males and 22 females. The mean age at surgery was 5.6 years (range, 7 months-15 years). The most common types of procedures performed were insertion of tissue expanders (N = 19), excision of facial dermoids (N = 7), torticollis release (N = 5), and excision of vascular lesions (N = 4). The remaining 6 patients underwent a variety of reconstructive procedures. The complication rate in the tissue expander group was 3 out of 39 expanders inserted (9.5%), and consisted of infection (N = 2) and rupture (N = 1). In the dermoid group, complications consisted of wound infection requiring reoperation (N = 1), and transient frontal paresis (N = 1). One patient in the hemangioma group had an incomplete resection necessitating open excision. The remaining patients all had satisfactory outcomes with no complications. The majority of the procedures were done on an outpatient basis. These results suggest that endoscopic techniques are eminently applicable in the pediatric population, providing the benefits of small and remote incisional wounds with complication rates that are comparable to those of conventional surgical treatment.

The differential diagnosis of posterior plagiocephaly: true lambdoid synostosis versus positional molding

The diagnosis and treatment of posterior plagiocephaly is one of the most controversial aspects of craniofacial surgery. The features of true lambdoid synostosis versus those of deformational plagiocephaly secondary to positional molding are inadequately described in the literature and poorly understood. This has resulted in many infants in several craniofacial centers across the United States undergoing major intracranial procedures for non-synostotic plagiocephaly. The purpose of this study was to describe the detailed clinical, imaging, and operative features of true lambdoid synostosis and contrast them with the features of positional plagiocephaly. During a 4-year period from 1991 to 1994, 102 patients with posterior plagiocephaly were assessed in a large multidisciplinary craniofacial program. During the same period, 130 patients with craniosynostosis received surgical treatment. All patients were examined by a pediatric dysmorphologist, craniofacial surgeon, and pediatric neurosurgeon. Diagnostic imaging was performed where indicated. Patients diagnosed with lambdoid synostosis and severe and progressive positional molding underwent surgical correction using standard craniofacial techniques. Only 4 patients manifested the clinical, imaging, and operative features of unilambdoid synostosis, giving an incidence among all cases of craniosynostosis of 3.1 percent. Only 3 among the 98 patients with positional molding required surgical intervention. All the patients with unilambdoid synostosis had a thick ridge over the fused suture, identical to that found in other forms of craniosynostosis, with compensatory contralateral parietal and frontal bossing and an ipsilateral occipitomastoid bulge. The skull base had an ipsilateral inferior tilt, with a corresponding inferior and posterior displacement of the ipsilateral ear. These characteristics were completely opposite to the findings in the 98 patients who had positional molding with open lambdoid sutures and prove conclusively that true unilambdoid synostosis exists as a specific but rare entity. Awareness of the features of unilambdoid synostosis will allow more accurate diagnosis and appropriate treatment of posterior plagiocephaly in general and in particular will avoid unnecessary surgical intervention in patients with positional molding.

Age-related 4,977 bp deletion in human lung mitochondrial DNA

The accumulation of mitochondrial DNA (mtDNA) mutations has been suggested to be an important contributor to human aging and degenerative diseases. The lung is exposed to ambient air and makes direct contact with the external environment. Numerous potentially noxious agents may damage lung tissues directly or indirectly through free-radical-mediated reactions. In previous studies, we demonstrated an age-dependent increase of mtDNA mutations in various human tissues. We hypothesize that the accumulation of the 4,977 bp (base pairs) deleted mtDNA in human lung tissues is also age-dependent. Using the polymerase chain reaction technique, we determined the incidence of the 4,977 bp-deleted mtDNA in 127 human lung specimens from 34-wk gestation to 79 yr of age. The results showed that 77 lung biopsies (60.6%) contained the 4,977 bp-deleted mtDNA, which started to appear in lung tissues after the fourth decade of life. The incidence apparently increased from 14.3% (one of seven) of the subjects in the 30- to 39-yr age group to 77.8% (two of 27) of the subjects in the 70- to 79-yr age group (p < 0.0001). The mean (+/- SEM) proportion of the 4,977 bp-deleted mtDNA in lung tissues significantly increased from 0.007 +/- 0.007% of the subjects in the 30- to 39-yr age group to 0.833 +/- 0.330% of those in the 70- to 79-yr age group (p < 0.005). Other factors such as sex, pulmonary function indices, and smoking status did not have statistically significant impact on the amount of the deleted mtDNA. These findings suggest that the accumulation of the 4,977 bp-deleted mtDNA is associated with aging human lung.

An intrinsic adrenergic system in mammalian heart

We have identified a previously undescribed intrinsic cardiac adrenergic (ICA) cell type in rodent and human heart. Northern and Western blot analyses demonstrated that ICA cell isolates contain mRNA and protein of enzymes involved in catecholamine biosynthesis. Radioenzymatic catecholamine assays also revealed that the catecholamine profile of adult rat ICA cell isolates differed from that of sympathetic neurons. Unlike sympathetic neuronal cells, isolated ICA cells have abundant clear vesicles on electron microscopy. Endogenous norepinephrine and epinephrine constitutively released by ICA cells in vitro affect the spontaneous beating rate of neonatal rat cardiac myocytes in culture. Finally, ICA cells could be identified in human fetal hearts at a developmental stage before sympathetic innervation of the heart has been documented to occur. These findings support the concept that these cells constitute an ICA signaling system capable of participating in cardiac regulation that appears to be independent of sympathetic innervation.

Preliminary results of triple therapy for obesity

OBJECTIVE

To evaluate the effectiveness of triple therapy in treatment of simple obesity.

SUBJECTS

Forty-five cases of simple obesity with a body mass index (BMI) above 30 kg/m2 and percentage of body fat more than 25% in males, and 30% in females were collected. Subjects were composed of 8 males and 37 females ranging in age from 16 to 70 years old with a mean age of 33.8 years.

METHODS

The triple therapy for obesity included weekly auricular acupuncture, diet control and aerobic exercise counseling for eight weeks. The reduction in body weight and body fat were measured upon just completing the therapeutic course. The changes of body weight in follow-up at one month and one year later were also analyzed respectively.

RESULTS

The results showed a 4.4 +/- 2.9 kg reduction in body weight and a 5.6 +/- 3.0% reduction in body fat after completing the treatment course. Five cases had their body weight reduced to within the normal range, 18 cases showed a marked effect (body weight reduced by more than 5 kg and body fat reduced more than 5%), 16 cases were considered effective (body weight reduced by 2-5 kg and body fat reduced by 1-5%), and 6 cases were considered to be ineffective (body weight reduced by less than 2 kg and body fat reduced by less than 1%). The rate of effectiveness was 86.7%. The rate of body weight rebound (weight regained more than 1.5 kg) was 6.7% and 18.9% one month and one year later, respectively. The effectiveness of weight reduction was significant correlated with the compliance of participants with each therapeutic method, but not with age. No special side effects were noted during or after the treatment except for two cases who had intolerable pain when receiving auricular acupuncture.

CONCLUSION

The triple therapy resulted in a satisfactory body weight reduction and a good maintenance of the target weight after treatment. Furthermore, more frequent aerobic exercise during the treatment course contributed greatly to body weight reduction and maintenance, as indicated by the correlation analysis.

Use of the silicone tracheal T-tube for tracheostenosis or tracheomalacia

BACKGROUND

Tracheobtenosib and tracheomalacia are trivial diseases. The conventional choice of managements with tracheostomy, either temporary or long-term usage, can only partially resolve the problems of airway obstruction. Silicone tracheal T-tube presents a substitute for it.

METHODS

We present 5 patients with tracheostenosis or tracheomalacia managed with nine procedures of long silicone Montgomery T-tube prothesis between 1984 and 1994 in VGH-Taipei. The primary diagnosis included tracheal injury (2), postintubation tracheal stenosis (2), and stenosis due to endotracheal tuberculosis (1). Three patients received a long segmental T-tube for permanent endotracheal stenting and the other two patients used T-tube insertion for temporary stenting of the trachea for 7 and 11 months, respectively, with satisfactory results.

RESULTS

All patients got immediate benefit from the prothesis in respiration with simple postoperative care. Two patients with temporary T-tube placement had it successfully removed in 7 and 11 months, respectively. Placement of the T-tube for subglottic stenosis also protected the function of phonation. The tracheal T-tube restored airway patency reliably with good long-term results and could be the preferred management of chronic upper airway obstructive disease not amenable to surgical repair. The most common complication was airway obstruction caused by either granulations or sticky mucoid substance. Three patients and six tubes (60%) developed granulation obstruction and the average duration of granuloma formation was 7.7 months. Laser phototherapy or surgical intervention, such as tracheoplasty, with change of the T-tube was carried out for granuloma obstruction.

CONCLUSIONS

T-tube is a good endoprothesis for tracheostenosis and tracheomalacia with minimal complication for cases of long tracheostenosis or complex tracheal injury.

Polysensory response characteristics of dorsal root ganglion neurones that may serve sensory functions during myocardial ischaemia

OBJECTIVE

To determine the response characteristics of dorsal root ganglion neurones that may serve sensory functions during myocardial ischaemia.

METHODS

Extracellular recordings were made from 54 spontaneously active and 5 normally quiescent dorsal root ganglion neurones (T2-T5) in 22 anaesthetized open-chest dogs under control conditions and during epicardial mechanical or chemical stimulation and myocardial ischaemia.

RESULTS

The activity of 78% of spontaneously active and all quiescent neurones with left ventricular sensory fields was modified by left ventricular ischaemia. Forty-six spontaneously active neurones (85%) were polysensory with respect to mechanical and chemical stimuli. The 5 quiescent neurones responded only to chemical stimuli. Spontaneously active neurones associated with left ventricular mechanosensory endings (37 neurones) generated four different activity patterns in response to similar mechanical stimuli (high or low pressure active, high-low pressure active, high-low pressure inactive). A fifth group generated activity which was not related to chamber dynamics. Adenosine, adenosine 5'-triphosphate, substance P and bradykinin modified 72, 61, 65 and 63% of the spontaneously active neurones, respectively. Maximum local mechanical or chemical stimuli enhanced activity to similar degrees, as did ischaemia. Each ischaemia-sensitive neurone displayed unique activity patterns in response to similar mechanical or chemical stimuli.

CONCLUSIONS

Most myocardial ischemia-sensitive dorsal root ganglion neurones associated with epicardial neurites sense mechanical and multiple chemical stimuli, a small population sensing only mechanical or chemical stimuli. Activity patterns generated by these neurones depend on their primary sensory characteristics or those of other neurones that may converge on them, as well as the type and magnitude of the stimuli that impinge upon their sensory fields, both normally and during ischaemia.

Preliminary experience in pelviscopic uterine suspension using Webster-Baldy and Franke's method

OBJECTIVE

To find which method gives the best relief from dyspareunia and pelvic pain caused by a retroverted uterus using the two methods mentioned as compared to other methods reported in the medical literature.

SUBJECTS

Twenty-five patients, with ages ranging from 25-55 years old, complaining of mild to severe pelvic pain and dyspareunia seeking treatment in our OPD were evaluated and treated in a span of 3 years' time.

METHODS

Pelviscopic retrouterine ligament fixation using Webster-Baldy and Franke's method were done after each patient was evaluated as to the uterine position, degree of misalignment of the uterus and severity of adhesion. Pelvic pain and dyspareunia were reproduced by palpation of the retroverted uterus. Ultrasonographies were performed to confirm initial findings and to rule out any ovarian or uterine abnormalities. Orthopedic and psychological consultations were done to rule out any orthopedic disorders or non-organic causes of their problem.

RESULTS

Of the twenty-five patients treated, 20 patients were treated using Webster-Baldy method and five patients were treated using Franke's method, all the patients (100%) experienced great improvement 6 weeks after the operation. After 6 months, 16 patients (80%) with the Webster-Baldy method and four patients (80%) with the Franke's method had complete relief from pelvic pain and dyspareunia. The remaining four patients (20%) with the former method and one patient (20%) with the latter method complained of mild abdominal discomfort. After 6 months to 2 years of follow-up, 17 patients with Webster-Baldy method and five patients with Franke's method (88%) had improved sexual life and the remaining three patients were lost to follow-up.

CONCLUSION

When dyspareunia and pelvic pain are caused by a retroverted method, we believe uterine suspension using different procedures will certainly relieve this problem. We have presented and have chosen these two procedures mainly due to their simplicity and the almost nil possibility of bowel intussusception into the anterior cul-de-sac as compared to other methods.

The early evaluation of induced osteoarthritis in rats with 99Tcm-pertechnetate scans

Osteoarthritis was induced in 30 adult rats by serial injection of papain (3.5 mg kg-1) into the right knee on days 1, 4 and 7 of the study, with equal volumes of normal saline being injected into the left knee as a control. The severity of the induced arthritis was observed after the subcutaneous injection of 37 MBq kg-1 (1 mCi kg-1) 99Tcm-pertechnetate in the neck 24 h and 1, 2, 4, 6 and 8 weeks after the first intra-articular injection of papain. The ratio of radioactivity in the right compared with the left knee of each rat was measured as an index of the severity of osteoarthritis. After the scans, X-rays of both knees were obtained. At each state of progression, a rat was sacrificed and bilateral knee sections were performed for further pathological evaluation. The results were then compared with the changes in the radioactivity ratio and the X-rays. The radioactivity ratio of the knees reached a peak approximately 25 min after the subcutaneous injection of 99Tcm-pertechnetate and this value was chosen as the index of the severity of osteoarthritis. Marked differences in radioactivity in the left and right knees were observed as early as 24 h after the first intra-articular injection of papain. The radioactivity ratio increased with time, which correlated well with pathological changes. Joint space narrowing was not found on X-ray until 4 weeks post-injection. The results showed that the 99Tcm-pertechnetate scans correlated well with the pathological changes and that this method can detect osteoarthritis earlier than joint X-rays. It is suggested that a 99Tcm-pertechnetate scan is a useful means of evaluating early changes in induced osteoarthritis in rats.

Management for patients with advanced T4 epidermoid carcinoma of the esophagus

Available data concerning the treatment of patients with advanced T4 esophageal carcinoma are limited. A consecutive series of 42 patients with advanced T4M0 epidermoid carcinoma of the esophagus were studied from June 1987 to July 1992. The aim of this study was to evaluate the efficacy of various therapeutic modalities, and further evaluate the therapeutic options. The various therapeutic modalities included the following: Group I, feeding jejunostomy or endoesophageal intubation, 6 patients; Group II, palliative subtotal esophagectomy only, 8 patients; Group III, bypass procedures without tumor resection, 9 patients; Group IV, nutritional support and then treatment with irradiation (n=8) or concurrent radio-chemotherapy (n=4), 12 patients; Group V, subtotal esophagectomy, followed by aggressive concurrent radiochemotherapy, 7 patients. The total prescribed irradiation dose was 60 Gy (10 Gy/5 fractions/week). A combination regimen of chemotherapy consisted of cisplatin, 5-fluorouracil, and leucovorin (PFL regimen). For the patients undergoing esophagectomy or bypass procedures (n=24), the rates of operative complication and mortality were 45.8% and 25%, respectively. Side effects of adjuvant therapy (n=24) consisted of main airway irritation (100%), mucositis or gastrointestinal symptoms (83.3%), hematologic toxicity (79.2%), esophagitis or gastric ulcer (62.5%), alopecia (37.5%), and pneumonia (20.8%). The mortality due to toxicity of adjuvant therapy was 21.1% (4/19 patients). The mean survival times for each of the different groups was 1.9+/-0.5 months for Group I, 4.8+/-1.6 months for Group II, 5.2+/-1.2 months for Group III, 7.3+/-2.0 months for Group IV, and 20.3+/-2.5 months for Group V, respectively. Compared with patients of Groups I--IV, the Group V patients had a significantly superior one-year survival rate (P<0.01). Our results demonstrated that esophagectomy followed by concurrent irradiation and PFL combination chemotherapy may provide a significant improvement in the quality of life and survival for appropriate patients with advanced T4M0 epidermoid carcinoma of the esophagus. Furthermore, more than one cycle of PFL regimen chemotherapy may result in a better prognosis. During the performance of such an aggressive treatment, the utmost care must be taken with the patient's nutrition and to prevent pulmonary complications.

[Effect of hemin in treating hemorrhagic anemia and toxicity]

AIM

To study the effect of hemin in treating hemorrhagic anemia and toxicity.

METHODS

Fifty rats with hemorrhagic anemia were randomly divided into 5 groups with different dosage of hemin (93, 168, 300 mg.kg-1.d-1), ferrous gluconate (FG 300 mg.kg-1.d-1), and water, ig for 7 d. Twenty mice fed with hemin (6.0 g.kg-1.d-1) in 24 h for observing acute toxicity effects. Long-term toxicity were observed in 80 rats given hemin (0.65, 1.3, 2.6 g.kg-1.d-1) in 3 months.

RESULTS

Hb of the rats of corresponding groups were 66-->121, 71-->141, 66-->148, 69-->140, and 67-->112 g.L-1. There were no adverse effects observed on acute toxicity test. No abnormalitis were found in hemogram, liver renal function test, and autopsy.

CONCLUSION

Hemin had a better effect than FG and no adverse effect was found in hemin.

Application of chaos theory to a model biological system: evidence of self-organization in the intrinsic cardiac nervous system

The neutral organization that determines the specific beat-to-beat pattern of cardiac behavior is expected to be demonstrated in the independent regulation of the RR intervals (chronotropy) and the corresponding QT subintervals (inotropy), as the former defines the rate of contraction and the latter has a linear negative correlation with the peak pressure inside the contracting ventricular muscles. The neurons of the isolated cardiac nervous system, many of which are located in the fat-pads of the heart, exhibit the same types of mechanical and chemical receptors and the same types of cholinergic and noradrenergic effectors as those found in the neural superstructure. In the surgically isolated and perfused rabbit heart we studied the responses of the QT and RR intervals evoked by block of coronary blood flow. We found that if we separated each RR cycle into QT and RR-QT components, then the dynamics of variation for each subinterval series often had the same fractional number of degrees of freedom (i.e., chaotic dimensions), a finding which suggests they are both regulated by the same underlying system. The ischemia/anoxia evoked transient dimensional increases and separations between the two subinterval series that, after the temporary divergence, reconverged to having the same lower value. The dimensional fluctuations occurred repeatedly and preceded or coincided with alterations in the magnitude and sign of the slope of QT vs RR-QT. We interpret the dimensional fluctuations of the two subinterval series as correlates of adaptation-dependent self-organization and reorganization in the underlying intrinsic cardiac nervous system during accumulating ischemia/anoxia. Such attempts at functional reorganization in this simple neurocardiac system may explain the transient dimensional changes in the RR intervals that precedes by 24 hrs the occurrences of fatal ventricular fibrillation in high-risk cardiac patients.

The reactivity of sera from patients with systemic lupus erythematosus to seven different species of single and double stranded deoxyribonucleic acids

OBJECTIVE

Anti-DNA antibodies are frequently found in the serum of patients with systemic lupus erythematosus (SLE). To understand whether the avidity of SLE sera to different species of single-stranded (ss) and double-stranded (ds) DNA is different or not, the reactivity of active SLE sera to seven species of DNA from viral, bacterial, piscine, and mammalian sources was compared.

METHODS

Nineteen sera from patients with active SLE were studied for their reactivity to different ssDNA and dsDNA from Escherichia coli (EC), Micrococcus lysodeikticus (ML), Clostridium perfringens (CP), calf thymus (CT), salmon testis (ST), human placenta (HP) and lambda phage by ELISA. The dsDNA was purified by treating it with S1 nuclease and proteinase K, followed by Sephacryl S-300 gel filtration. The ssDNA was purified by absorption on a hydroxyapatite column after heat-cleavage of the dsDNA.

RESULTS

The reactivity of SLE sera to 7 species of dsDNA was not significantly different and they recognized a more widely shared epitope. In contrast, the reactivity of these sera to 7 species of ssDNA was erratic and the antigens could be grouped into high (CP and HP), medium (EC, ML, CT, and ST) and low (lambda-phage) antigenicities.

CONCLUSION

The anti-ssDNA and anti-dsDNA antibodies of SLE patients recognize more widely shared determinants on the DNA of seven different species. Lambda-phage DNA shows the poorest immunogenicity among them.

DNA flow cytometric analysis of chest-wall chondroma and chondrosarcoma

DNA flow cytometric analysis was performed for prediction of malignancy potential, and hence of outcome, in 17 patients aged 29-76 (mean 52) years with cartilaginous tumour of the chest wall. Histologically there were nine chondromas and eight chondrosarcomas. The chondrosarcomas (3 grade I, 4 grade II, 1 grade III) were significantly larger than the chondromas (13.6 +/- 7.8 vs 4.2 +/- 2.0 cm, p < 0.001). DNA flow cytometry was performed on paraffin-embedded blocks of resected tumour. In eight of the 17 tumours (6 chondromas, 1 grade I and 1 grade II chondrosarcoma) measurement of DNA content failed because of low cellularity and severe calcification. Aneuploid DNA content was detected only in three chondrosarcomas (2 grade II, 1 grade III). The synthetic phase fraction was less than 15% in all the studied chondromas, but exceeded 25% in four of six chondrosarcomas. This case series though small, may indicate a trend towards association between higher histologic grading and greater incidence of aneuploidy with higher synthetic phase fraction. Tumour size, histologic grade, DNA ploidy and adequacy of surgical resection are the main influences on prognosis.

Use of fluorine-18 fluorodeoxyglucose positron emission tomography in the detection of thymoma: a preliminary report

Thymomas are lacking in malignant cytological features. Their staging is defined by the invasiveness of the tumour. This study aimed to analyse the uptake patterns of fluorine-18 fluorodeoxyglucose (FDG) in thymomas of different stages. FDG positron emission tomography (PET) scan was performed in 12 patients suspected of having thymoma and in nine controls. Qualitative visual interpretation was used to detect the foci with FDG uptake higher than that of normal mediastinum. Tumour/lung ratio (TLR) was calculated from the counts of ROIs over the mass and over comparable normal lung tissue in thymoma patients. Mediastinum/lung ratio (MLR) was calculated from the counts of ROIs over the anterior mediastinum and lung in controls. The PET scan patterns of distribution of foci with FDG uptake and TLRs were correlated with the computed tomography (CT) or magnetic resonance imaging (MRI) findings, and staging of the thymomas. Thymectomy was performed in ten patients and thoracoscopy was done in two patients. The results revealed ten thymomas (two stage I tumours, two stage II, four stage III and two stage IV, according to the Masaoka classification), and two cases of thymic hyperplasia associated with myasthenia gravis. Myasthenia gravis was also noted in four thymoma patients. FDG studies showed (a) diffuse uptake in the widened anterior mediastinum in patients with thymic hyperplasia, (b) confined focal FDG uptake in the non-invasive or less invasive, stage I and II thymomas, and (c) multiple discrete foci of FDG uptake in the mediastinum and thoracic structures in stage III and IV advanced invasive thymomas. The thymomas had the highest TLRs, followed by the TLRs of thymic hyperplasia and the MLRs of control subjects (P <0.005). No significant difference was found between thymomas in different stages or between thymomas with and thymomas without myasthenia gravis. In comparison with CT and/or MRI, FDG-PET detected more lesions in patients with invasive thymomas and downgraded the staging of thymoma in four patients. Our preliminary results suggest that FDG-PET is useful in the assessment of the invasiveness of thymomas, and may have the potential to differentiate thymomas from thymic hyperplasia.

Nitric oxide modulates signaling between cultured adult peripheral cardiac neurons and cardiomyocytes

To determine whether nitric oxide (NO) modifies cardiomyocytes directly or indirectly via peripheral autonomic neurons, the effects of NO were studied in long-term (3-6 wk) cultures of adult guinea pig ventricular myocytes alone as well as in cocultures with adult extracardiac (stellate ganglion) or intrinsic cardiac neurons. NADPH diaphorase was associated histochemically with cultured intrinsic cardiac and, to a lesser extent, stellate ganglion neurons. The beating frequency of ventricular myocytes cocultured with intrinsic cardiac neurons (M-intrinsic) or stellate ganglion neurons (M-stellate) increased by 20-30% (P < 0.001) after administration of the NO donor S-nitroso-N-acetylpenicillamine (SNAP); this effect was abolished by the guanylate cyclase inhibitor LY-83583. The beating frequency of noninnervated myocyte cultures was not affected by SNAP. The precursor of NO, L-arginine, also increased the beating rate (approximately 20%; P < 0.05) of M-intrinsic cocultures, not affecting that of M-stellate cocultures or noninnervated myocyte cultures. Augmentor effects induced by SNAP were no longer elicited in the presence of tetrodotoxin and were unaffected by beta-adrenergic or muscarinic receptor blockade. It is concluded that 1) NO-sensitive neurons are present in stellate and intrinsic cardiac ganglia, and these neurons increase the beating rate of cardiomyocytes in the presence of NO; 2) more NO-synthesizing neurons are present in M-intrinsic than M-stellate cocultures, since L-arginine increased the beating frequency of myocytes significantly only in M-intrinsic cocultures; and 3) the beating rate of noninnervated myocyte cultures is not directly affected by NO.

Ventricular sensory neurons in canine dorsal root ganglia: effects of adenosine and substance P

Effects elicited by adenosine and substance P on ventricular sensory endings of 14 dorsal root ganglion afferent neurons were studied in situ in anesthetized dogs. Sensory-field application of adenosine (1 microM) increased the activity of these neurons by 179%. Application of a nonspecific adenosine antagonist to epicardial sensory fields suppressed ongoing activity in all 14 neurons by 39%. Application of an A1- or A2-adenosine-receptor antagonist suppressed activity generated by 10 of these neurons by 44 and 59%, respectively. Adenosine applied after A1- or A2-receptor blockade increased activity in 10 neurons by 131 and 145%, respectively, indicating that A1- and A2-receptor effects were not additive. Application of substance P (1 microM) to identified sensory fields increased activity in 12 of these neurons by 169%, whereas application of a substance P-receptor antagonist reduced activity generated by these neurons by 75%. Myocardial ischemia increased activity of nine neurons associated with left ventricular sensory fields by 320%, an effect that was counteracted by the nonspecific adenosine-receptor antagonist. It is concluded that A1- and A2-adenosine receptors, as well as substance P receptors, are present on ventricular epicardial sensory nerve endings of dorsal root ganglion neurons that are tonically active during normal states, becoming further activated during ischemia.

A multivariate analysis of prognostic factors in thymoma

BACKGROUND

Considering the prognostic factors of thymoma, the clinical stage is the most important, while controversies exist about other clinicopathologic factors. A multifactorial study was carried out to clarify the relationship between prognosis and sex, age, tumor size, presence of myasthenia gravis, staging, epithelial subtyping, lymphocyte/epithelial cell ratio (L/E ratio) and other adjuvant pathological features.

METHODS

One hundred and thirty-seven cases were collected in Veterans General Hospital-Taipei from 1961 to 1993. The aforementioned features were studied. Kaplan-Meier's actuarial survival analysis was adopted, with Logrank test, to determine the significance of overall heterogeneity and trend. Cox proportional hazard model was also used for multivariate analysis.

RESULTS

Among all tested prognostic factors, staging had the highest significance (relative risk = 3.00, p < 0.001) and age had only a moderate one (relative risk = 1.04, p = 0.011). No other clinicopathological factor showed any statistical significance for prognosis.

CONCLUSIONS

Staging remains of greatest usefulness in predicting the biological behavior of thymoma. The effect of age requires more investigation. Other clinicopathological features have no definite influence in survival expectancy.

Percutaneous trans-hepatic cholangioscopy and lithotripsy in the treatment of intrahepatic stones: a study with 5 year follow-up

BACKGROUND

Intrahepatic stones are characterized by high treatment failure and recurrence rates. In the past, surgery played a major role in the management of this disease, but surgical intervention may not be feasible in previously operated patients or those classified as poor surgical risks. The development of percutaneous trans-hepatic cholangioscopy and lithotripsy has played an important role in the treatment of these patients.

METHODS

We reviewed our results in 165 patients with intrahepatic stones treated by percutaneous trans-hepatic cholangioscopy and lithotripsy in the past 12 years.

RESULTS

The rate of complete stone removal was 80% (132 cases) and the rate of recurrent biliary stones after a mean 58 month follow-up interval was 32.6% (43 of 132 cases). There were 2 deaths during the treatment period and 10 deaths during follow-up.

CONCLUSIONS

Percutaneous trans-hepatic cholangioscopy and lithotripsy are good alternatives in treating primary intrahepatic stones, especially for those patients unsuitable for surgery.

Morbidity and mortality after radical gastrectomy for patients with carcinoma of the stomach

BACKGROUND

This study sought to analyze the morbidity and mortality rates after radical gastrectomy for carcinoma, since the operation has been criticized as too morbid for the benefits it may provide.

STUDY DESIGN

A prospective study of 474 patients who underwent radical gastrectomy was conducted.

RESULTS

The overall morbidity and mortality rates were 20.1 and 3.0 percent, respectively. The morbidity and mortality rates fell significantly from 27.0 to 15.7 percent (p = 0.003) and 5.5 to 1.1 percent (p < 0.001), respectively, after the first 200 cases. By logistic regression analysis, it was found that male gender, combined organ(s) resection, extended lymphadenectomy, respiratory system disease, and tumor location were significantly related to postoperative morbidity. In regard to the extent of lymphadenectomy, relative to R2 resection (n = 102), the odds ratio for morbidity after R3 resection (n = 217) was 2.13, and for R4 resection (n = 155) it was 3.12. Age older than 65 years, total gastrectomy, combined organ(s) resection, and respiratory system disease were factors that negatively affected operative mortality.

CONCLUSIONS

These observations suggested that radical gastrectomy can be performed with an acceptable risk of morbidity and mortality in a general hospital.

Emergency surgical intervention for severe corrosive injuries of the upper digestive tract

BACKGROUND

In treating severe corrosive injury of the esophagus and stomach, prompt diagnosis, adequate fluid resuscitation and warranted surgical intervention are the most important factors in rescue of critically ill patients. The purpose of this study was to evaluate the need for, and the advantages of, a surgical approach to treatment of such corrosive injuries to the upper gastrointestinal (UGI) tract, as well as to select the most suitable technique to achieve a good survival rate.

METHODS

From January 1983 to December 1991, 220 patients were treated for caustic ingestion injury to the UGI tract. A retrospective review of their records allowed targeting of 27 patients with severe corrosive injury that surgical intervention was required. In this study, peritoneal sign was taken as the key indicator for early emergency operation. The age, sex, elapsed time from injury to operation, the sort and quantity of caustic agent used, injury mechanism, clinical manifestations, alternative surgical treatment methods and causes of death were also reviewed and analyzed in this study.

RESULTS

The patients included 13 men and 14 women, of whom the majority were adults (96.3%) who had attempted suicide (85.2%). All of them had taken liquid corrosive agents, usually hydrochloric acid (63%). Eighteen underwent emergency operations; the other nine received only supportive treatment, given their terminal status. The mortality rates for patients with surgery and supportive treatment were 66.7% and 100%, respectively. Four patients died after undergoing esophagectomy with resection of the stomach using the thoracoabdominal method. Only three of the eight patients who received esophageal stripping combined with resection of the stomach through the abdomen died (37.5%).

CONCLUSIONS

The time elapsed between injury and development of peritoneal sign is a good indicator of the severity and extent of the injury. When peritoneal sign manifests at a very early stage, it is an indicator that the corrosive injury is very advanced in its progress and that, no matter what procedures were performed, the outcome would be the same. Yet if there were a six-hour gap then aggressive surgical management can rescue some patients. It is recommended based on experience here, that when using the surgical approach, resection of the stomach with stripping of the esophagus is superior to the thoracoabdominal method.

Primary uncommon malignant tumors of the esophagus: an analysis of 30 cases

BACKGROUND

Uncommon malignant tumors of the esophagus are defined as any histological type of malignant esophageal tumors other than the typical squamous cell carcinoma. Their biological characteristics remain obscure because of their rarity. Thus, this is a retrospective review of patients here with uncommon esophageal cancers in an attempt to evaluate their prognostic factors and proper therapeutic modalities.

METHODS

Among 1,674 patients with esophageal cancers, only 30 (1.8%) with uncommon esophageal cancers were collected between 1977 and 1992. The clinical parameters for evaluation consisted of age, sex, histological type, location, staging and a variety of therapeutic management techniques and their results.

RESULTS

Histologically, there were 10 adenocarcinomas, 7 small cell carcinomas, 6 adenosquamous carcinomas, 3 carcinosarcomas, 1 mucoepidermoid carcinoma, 1 adenoid cystic carcinoma, 1 fibrosarcoma, and 1 basal cell carcinoma. The mean age was 65.8 years, ranging from 46 to 85 years. Upon admission to hospital, the most common clinical symptoms included dysphagia, body weight loss and substernal pain. The tumor staging, according to TNM classification was evaluated as follows: Stage I: 13.3%, Stage II: 46.7%, Stage III: 16.9%, Stage IV: 23.3%. The middle third thoracic esophagus was the most common location of tumor occurrence. Overall one-year, two-year, and five-year survival rates were 39.3%, 21.4%, and 10.7% respectively. These results were as poor as those of squamous cell carcinoma. However, the patients with Stage I and Stage II tumors (mean, 23.8 months) had significantly better survivals than those with Stage III and Stage IV (mean, 3.9 months). Furthermore, if the tumor was resectable, the patients undergoing esophagectomy had much better one-year and two-year survival rates than those without esophagectomy (p < 0.01). In addition, patients with small cell carcinoma seemed to have worse treatment outcome than those with other histological types of tumors.

CONCLUSIONS

These results suggested that key factors contributing to prognosis included tumor staging as well as respectability. Thus, it is recommended that, with early detection and diagnosis, esophagectomy might be the treatment-of-choice in managing these uncommon esophageal malignancies. Adjuvant therapy including irradiation and chemotherapy may be helpful, particular for small cell carcinoma.

Preoperative assessment of choledocholithiasis in laparoscopic cholecystectomy

In order to determine the predictive value of noninvasive investigations for choledocholithiasis, we conducted a prospective preoperative study on 82 patients with symptomatic gallstones who received laparoscopic cholecystectomy. Ultrasonography (US), liver function tests and endoscopic retrograde cholangiography (ERC) were routinely performed in all cases prior to operation. The results showed a strong correlation between noninvasive procedures (liver function tests and US) and the presence of choledocholithiasis as shown by ERC. Using ERC as a reference, the sensitivity and selectivity of ductal dilatation at US and the elevation of alkaline phosphatase (ALP), gamma-glutamyltransferase and total bilirubin in the serum were studied for the detection of common bile duct (CBD) stones. The values of the combination of these tests were also calculated. From receiver operator characteristics curves, the best cut-off point for US in conjunction with ALP was chosen. ERC should be restricted to patients with possible CBD stones, suspected after a combination of the noninvasive US and ALP tests. This study emphasized the necessity and timing of performing ERC as a preoperative modality in the detection of choledocholithiasis in patients who are to undergo laparoscopic cholecystectomy.

An ultrastructural characterization of in vitro-assembled hnRNP C protein-RNA complexes

In mammalian cells approximately 700 nucleotide lengths of pre-mRNA are packaged during transcription by a unique group of abundant nuclear proteins to form a repeating array of regular ribonucleoprotein complexes termed 30-40S heterogeneous nuclear ribonucleoprotein particles (hnRNP particles). We have used electron microscopy to examine complexes that form when in vitro-transcribed RNA is bound by one of the purified native core-particle proteins which comprise the 40S monoparticle (the C protein tetramer). Negatively stained images of the C protein tetramer bound to particle-length RNA (700 nt) demonstrate that three tetramers bind each RNA molecule to form a stable closed triangular complex. The triangular complexes have an isosceles shape with a base of 18.0 nm and sides of 23.0 nm. When RNA molecules of 230 nt are used as substrates single tetramers bind to form complexes that appear as small rounded structures with an average diameter of 9.7 nm. Twice this length of RNA (456 nt) supports the assembly of mostly bilobed complexes that are 20.4 nm long and 11.8 nm wide. Images of the C protein-RNA complexes which assemble on 1400-nucleotide lengths of RNA (two particle lengths of RNA) clearly show complexes composed of two triangles while three-triangle complexes are seen when 2100-nt lengths of RNA are used as the assembly substrate. These ultrastructural results demonstrate that groups of three C protein tetramers combine with the length of RNA packaged in monoparticles to form a discreet triad structure.(ABSTRACT TRUNCATED AT 250 WORDS)

Shortening of the QT interval of the EKG is associated primarily with increased ventricular contractility rather than heart rate

The objective of this study was to gather direct evidence on whether the duration of the QT interval relates primarily to heart rate or to ventricular contractility. The electrocardiographic and cardiodynamic consequences of electrical stimulation (15 V, 5 ms, 10Hz) of various intrathoracic sympathetic efferent neuronal structures were studied in 10 anesthetized mongrel dogs. Stimulation of efferent sympathetic axons in the right intraganglionic nerve, which innervates the sinoatrial node, induced tachycardia (110 +/- 5 - 133 +/- 6 bpm; p < 0.01) without significantly altering right or left ventricular intramyocardial ventricular chamber pressures. The QT interval, as determined by leads I, II and III of the EKG and a transthoracic lead, was not affected by this intervention 310 +/- 8 - 302 +/- ms). Increasing heart rate to a similar degree (111 +/- 3 - 131 +/- 3 bpm) by right atrial pacing did not induce changes in the QT interval. When right (23 +/- 3 - 49 +/- 8 mm Hg; p < 0.01) and left (81 +/- 10 - 127 +/- 19 mm Hg; p < 0.01) ventricular forces were augmented without concomitant increases in heart rate by stimulating efferent sympathetic axons in the left caudal pole cardiopulmonary nerve the QT interval shortened (322 +/- 11 - 290 +/- 12 ms; p < 0.01). Only when an efferent sympathetic nerve, that contains fibers destined for both the sinoatrial node and the ventricles was stimulated did both heart rate and ventricular contractility augment and QT shorten (318 +/- 10 - 290 +/- 11 ms; p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Deletion analysis of protein kinase C inactivation by calphostin C

Protein kinase C (PKC) undergoes specific inactivation by nanomolar concentrations of calphostin C. Both PKC-alpha (a Ca(2+)-dependent conventional isoform) and PKC-epsilon (a Ca(2+)-independent novel isoform) are similarly inactivated by calphostin C (75-100 nM produced 50% inhibition), suggesting that inactivation requires a site common to both classes of PKC. We therefore performed studies to identify a critical region in the regulatory domain of PKC-alpha required for inactivation by calphostin C. A series of N-terminal-truncation mutants of bovine PKC-alpha expressed in Saccharomyces cerevisiae was tested with 500 nM calphostin C, a concentration sufficient to inactivate wild-type PKC-alpha by 80-90%. This concentration was as effective with mutant proteins containing deletions of up to 91 amino acid (aa) residues from the amino terminus (ND91), whereas a mutant protein truncated by 140 aa (ND140) was inactivated by only 20%. These findings imply that the aa sequence 92-140 is a structural determinant of PKC-alpha inactivation by calphostin C. This sequence contains one of the phorbol ester-binding sites (aa 102-144), which is highly conserved among most PKC isoforms including PKC-epsilon. In addition to aa 92-140, PKC-stimulating cofactors (phosphatidylserine, phorbol ester, and Ca2+) are required for inactivation by calphostin C even in the case of PKC mutants that do not require these cofactors for enzymatic activity. These results suggest that cofactors provide a template that is required for productive interaction of PKC and the inhibitor. The significance of the proposed proximity effect to calphostin C action is discussed.

Management of primary chest wall tuberculosis

Primary tuberculosis of the chest wall is rare and its clinical presentation may resemble pyogenic abscess or tumour. The diagnosis is difficult, since smears or cultures of aspirate frequently fail to show tubercle bacilli. Seven cases of primary chest-wall tuberculosis treated between 1973 and 1992 are described. All presented with a progressively enlarging mass. The diagnosis was based on bacteriologic and histologic findings, but definitive diagnosis was obtained before treatment in only two cases. Satisfactory results were obtained with surgical debridement and specific chemotherapy in six cases and with chemotherapy alone in one case. From this limited experience, we suggest that primary chest-wall tuberculosis should initially be treated with a combination regimen of antituberculous chemotherapy, which should take more than 9 months. If the lesion progressively enlarges or secondary infection occurs, however, adequate surgical debridement is also required.

Unexpected interaction between beta-adrenergic blockade and heart rate variability before and after myocardial infarction. A longitudinal study in dogs at high and low risk for sudden death

BACKGROUND

Heart rate (HR) variability is a marker of tonic cardiac autonomic activity and contributes in assessing risk for sudden death after myocardial infarction. Recent clinical observations have indicated that attenuation of HR variability, which occurs after myocardial infarction, may be transient. This study addresses the issue of whether autonomic control of heart rate recovers at different rates after myocardial infarction in subjects at high and low risk for ventricular fibrillation (VF).

METHODS AND RESULTS

Thirty dogs, 22 with myocardial infarction and 8 sham-prepared animals, completed the study. Changes and recovery in cardiac autonomic activity after myocardial infarction were examined by measuring HR variability before and at defined intervals during the first 30 days after infarction. Each HR variability measurement was made before and after beta-blockade in dogs at high (n = 10) and low (n = 12) risk for VF. Arrhythmia risk was determined on the basis of development of VF during exercise and transient myocardial ischemia 30 days after infarction. No sham-prepared animals developed VF. Preinfarction measurements of HR variability were not different between the groups before beta-blockade, but HR variability increased much more in response to beta-blockade in animals destined to be resistant compared with susceptible animals (289 +/- 26 to 369 +/- 35 msec, delta 27.7%, versus 270 +/- 36 to 283 +/- 34 milliseconds, delta 4.8%, respectively, P < .01). Immediately after infarction, HR variability was significantly attenuated in all dogs, but in the resistant dogs it recovered to pre-myocardial infarction levels within 10 days. After the infarction, beta-blockade did not increase HR variability in either group of animals. Postoperative increases in HR variability from beta-blockade were preserved in the sham group. Susceptible animals were characterized by a persistent attenuation of HR variability throughout the 30 days.

CONCLUSIONS

The depression in HR variability produced by myocardial infarction has a clearly different temporal recovery pattern between low- and high-risk animals. After myocardial infarction, beta-adrenergic blockade does not alter HR variability, thus preserving its predictive value. Before myocardial infarction, however, beta-blockade increases HR variability only in the animals destined to be at low risk for lethal arrhythmias after the infarction. The recovery pattern of HR variability after myocardial infarction may contribute to the early recognition of individuals at high risk for sudden death.

Pleural and pericardial mesothelioma in a general teaching hospital during the last fourteen years

BACKGROUND

Mesothelioma is not common in Taiwan; its clinical manifestations and biological behavior in the Chinese patients have thus rarely been discussed.

METHODS

The chart records of mesothelioma patients collected from 1979 to 1992 in Veterans General Hospital-Taipei were retrospectively reviewed.

RESULTS

Sixteen thoracic mesotheliomas were diagnosed in 15 patients, including 5 benign fibrous mesotheliomas, 1 malignant pericardial mesothelioma and 10 malignant pleural mesotheliomas. One patient suffered from benign fibrous mesothelioma initially, and the disease transformed into malignant mesothelioma 5 years later. Symptoms of benign fibrous mesothelioma were nonspecific and all 5 cases occurred in lower pleural cavities. One case presented with repeated hypoglycemic coma and the initial diagnosis was hepatoma. History of asbestos exposure probably occurred in 3 of 10 malignant pleural mesotheliomas. The median survival of malignant pleural mesothelioma after onset of symptoms was 14 months. Survival seemed better in epithelial type and those who received surgical treatment of malignant mesothelioma.

CONCLUSIONS

The symptoms of mesothelioma were nonspecific. Benign fibrous mesothelioma should be considered in patients with palpable liver and hypoglycemic symptoms. Malignant transformation can occur in benign fibrous mesothelioma. Survival of malignant mesothelioma seems better in epithelial type and in those who received surgical treatment.

Responsiveness of in situ canine nodose ganglion afferent neurones to epicardial mechanical or chemical stimuli

OBJECTIVE

The aim was to determine the capacity of nodose ganglion afferent neurones with epicardial sensory endings to respond to mechanical and chemical stimuli, in particular to purinergic compounds.

METHODS

Alterations in spontaneous activity generated by epicardial afferent neurones in nodose ganglia in situ of 17 anaesthetised dogs were identified using extracellular recording techniques when mechanical and chemical stimuli were applied to their receptor fields, as well as during brief periods of coronary artery occlusion.

RESULTS

92 cardiac afferent neurones were identified. Localised epicardial distortion modified the activity generated by 34 neurones [0.19(SEM 0.02) to 1.2(0.4) impulses.s-1]. Application of bradykinin, substance P, N6-cyclopentyladenosine or beta, gamma-methylene adenosine 5'-triphosphate to localised epicardial fields altered the activity of 69 neurones. Thus the majority of identified epicardial neurones responded to chemical stimuli alone (63%) as opposed to mechanical stimuli alone (25%), 12% responding to both types of stimuli. Activity was enhanced overall by chemical stimuli from a mean range of 0.1-0.4 to 11.6-13.2 impulses.s-1. Following termination of short lasting chemical as opposed to mechanical stimuli, activity remained increased for up to 45 min. Activity generated by 16 chemosensitive neurones was modified by brief periods of coronary artery occlusion [0.26(0.12)-1.66(0.61) impulses.s-1]; activity increasing further [2.51(0.47) impulses.s-1] during reperfusion periods.

CONCLUSIONS

(1) Chemical stimuli induce an order magnitude greater enhancement of activity generated by nodose ganglion cardiac afferent neurones than do mechanical stimuli, such enhancement persisting long after removal of chemical as opposed to mechanical stimuli. Thus qualitative and quantitative differences exists between central neuronal inputs derived from nodose ganglion epicardial afferent neurones sensitive to chemical as opposed to mechanical stimuli. (2) Adenosine and ATP can activate nodose ganglion cardiac afferent neurones.

Clinical evaluation of a renal mass diagnostic expert system

In this paper, we describe our clinical evaluation of the diagnostic accuracy of the renal mass diagnostic system (RMDS) and of seven physicians. To investigate the value of intravenous urography (IVU) and/or retrograde urography (RU) in diagnosing renal parenchymal tumors and tumors of the renal pelvis, RMDS and the seven physicians were tested with and without the information regarding IVU/RU at two different times. From this study we believe that RMDS can help residents in making more accurate presurgical renal mass diagnosis, and may eliminate the need for IVU/RU in the diagnosing process for a specific group of patients.

Pure cheiro-oral syndrome due to a small pontine hematoma: report of a case and review of the literature

Cheiro-oral syndrome is frequently associated with other neurologic deficits; its pure form is rare. We report a 60-year-old man with pure cheiro-oral syndrome due to a small hematoma located in the ventral tegmentum of the right upper pons. His sensory disturbance remained unchanged during a follow-up period of 16 months. Review of the literature suggests that the pons is the most frequent site of lesions in pure cheiro-oral syndrome.

Carcinosarcoma of the lung: an analysis of 6 operated cases

BACKGROUND

Carcinosarcoma of the lung is a rare malignant pulmonary neoplasm, and constitutes 0.1% to 0.3% of all lung tumors. Typically, these tumor have both carcinomatous and sarcomatous components with a poor prognosis due to late diagnosis and early metastases.

METHODS

From July 1980 to December 1993, six patients with pulmonary carcinosarcoma who underwent surgical treatment were studied. None of them had accurate tissue diagnosis before operation except one case with peripheral variant carcinosarcoma who was diagnosed by percutaneous transthoracic fine needle biopsy under sonographic guidance. All of our patients had a huge peripheral lung tumor 3.8 to 10 cm in diameter. Pneumonectomy was done in two patients, and lobectomy in three. The other patient had unresectable tumor.

RESULTS

The histopathological components in carcinoma were epidermoid carcinoma in and adenocarcinoma in 3. Differentiation of sarcomatous lesions included spindle cell sarcoma in 3, fibrosarcoma in 2 and undifferentiated mesenchymal sarcoma in one patient. In the resectable group, 1 was at stage II and 4 were at stage IIIa. None of the patients survived more than 2 years due to distant metastasis and cachexia. The mean survival was 140 days.

CONCLUSIONS

The carcinomatous portion tends to metastasize to regional lymph nodes whereas the sarcomatous part gives rise to systemic dissemination. Due to early systemic dissemination and poor prognosis, combination of extensive surgical intervention resection with aggressive postoperative chemotherapy and radiotherapy might be a reasonable consideration to improve survival in primary pulmonary carcinosarcoma.

Ventricular arrhythmias induced by chemically modified intrinsic cardiac neurones

OBJECTIVE

The aim was to investigate whether intrinsic cardiac neurones can be involved in the genesis of ventricular arrhythmias.

METHODS

Nicotinic, muscarinic, beta adrenergic, peptidergic, and amino acidergic agonists, as well as purinergic compounds, were individually administered in microliter quantities adjacent to spontaneously active in situ right atrial neurones in 57 anaesthetised dogs before and after acute decentralisation.

RESULTS

Ventricular arrhythmias were induced in one third of the dogs following neurochemical administration. Ventricular arrhythmias are induced much less frequently when intrathoracic extracardiac neurones are modified chemically. Salvos of ventricular premature contractions or ventricular tachycardias were elicited when intrinsic cardiac neurones were modified locally applied nicotine, bethanechol, isoprenaline, angiotensin II, bradykinin, substance P, vasoactive intestinal polypeptide, glutamate, or adenosine. In 60% of those instances in which intrinsic cardiac neuronal activity was modified by a neurochemical, ventricular arrhythmias were elicited. When arrhythmias were induced, activity generated by chemically modified intrinsic cardiac neurones increased from 0.7(SD 0.2) to 2.2(0.4) impulses.s-1 (p < 0.05). Following decentralisation of the intrinsic cardiac nervous system, repeat administration of the same neurochemicals into the same loci elicited ventricular arrhythmias in 42% of those dogs in which ventricular arrhythmias had been elicited previously. Neuronal activity increased [0.8(0.5) to 2.1(0.6) impulses.s-1; p < 0.05] in 86% of these instances.

CONCLUSIONS

Intrinsic cardiac neurones can be involved in the genesis of ventricular arrhythmias.

Purinergic modulation of adult guinea pig cardiomyocytes in long term cultures and co-cultures with extracardiac or intrinsic cardiac neurones

OBJECTIVE

To determine the capacity of ATP to modify cardiomyocytes directly or indirectly via peripheral autonomic neurones, the effects of various purinergic agents were studied on long term cultures of adult guinea pig ventricular myocytes and their co-cultures with extracardiac (stellate ganglion) or intrinsic cardiac neurones.

METHODS

Ventricular myocytes and cardiac neurones were enzymatically dissociated and plated together or alone (myocytes only). Myocyte cultures were used for experiments after three to six weeks. The electrical and contractile properties of cultured myocytes and myocyte-neuronal networks were investigated.

RESULTS

The spontaneous beating frequency of ventricular myocytes co-cultured with stellate ganglion neurones increased by approximately 140% (p < 0.001) following superfusion with 10(-5) M ATP. This effect was not modified significantly by tetrodotoxin or by beta adrenoceptor blockade (10(-5) M timolol), but was eliminated following application of the P2 antagonist suramin (10(-5) M). Basal spontaneous contractile rate was reduced by approximately 86% (p < 0.001) in the presence of suramin, indicating the existence of tonically active purinergic synaptic mechanisms in stellate ganglion neurone-myocyte cocultures. Suramin did not significantly affect non-innervated myocyte cultures. ATP increased myocyte contractile rate in intrinsic cardiac neurone-myocyte co-cultures by approximately 40% (p < 0.01) under control conditions, but when beta adrenergic receptors of tetrodotoxin sensitive neural responses were blocked, ATP induced greater augmentation (> 100%). In contrast, ATP induced much smaller effects in non-innervated myocyte cultures (approximately 26%, p < 0.01). Analogues of AT) showed the following order of potency: ATP > UTP > MSATP > beta gamma ATP > alpha beta ATP. Adenosine (10(-4) M) attenuated the beating frequency of myocytes in both types of co-culture, while not significantly affecting non-innervated myocyte cultures.

CONCLUSIONS

The experimental model used in this study showed that extrinsic and intrinsic cardiac neurones which possess P2 receptors can greatly enhance cardiac myocyte contractile rate when activated by ATP. Since adenosine reduced contractile rate in both types of co-cultures while not affecting non-innervated myocytes, it is concluded that some of these neurones possess P1 receptors.

Tumor recurrence in long-term survivors after treatment of carcinoma of the esophagus

To evaluate the status of tumor recurrence and the possible factors relevant to tumor recurrence among patients who survived more than 5 years after subtotal esophagectomy for the treatment of squamous cell carcinoma of the esophagus, a total of 104 patients who received treatment between 1959 and 1986 were reviewed. In 18 of these 104 patients, local or distant tumor recurrence developed, for a tumor recurrence rate of 17.3%. Eleven (61.1%) of these 18 patients eventually died of carcinomatosis despite further radiotherapy or chemotherapy, or both, and 4 patients with the disease are still alive. Three patients continue to survive after aggressive therapy was instituted for control of the locally recurrent tumor. Sixty-nine of the 104 patients are alive without tumor recurrence after the initial esophagectomy, and the remaining 17 patients died of miscellaneous causes. Tumor recurrence appears to be the most important factor affecting the prognosis in long-term survivors with resectable esophageal carcinoma. Among the 11 patients who died of tumor recurrence, 10 died within 5 to 9 years of their esophagectomy. The incidence of various modes of tumor recurrence among these 18 patients was as follows: blood-borne metastasis, 61%; lymph node recurrence, 33%; and locoregional organ recurrence, 33%. Factors that may be pertinent to a higher tumor recurrence rate include male sex, moderate to poor tumor differentiation, the presence of lymph node metastasis, and late stage of disease (stage IIb or worse). However, we could not find any statistical significance among these possible factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma arginase concentration measured by an enzyme-linked immunosorbent assay (ELISA) in normal adult population

Human liver arginase has many biological effects on lymphocytes, macrophages, liver cells, and tumor cells, in addition to its major role in the liver urea cycle. We have developed a sandwich enzyme-linked immunosorbent assay (ELISA) method to quantitate arginase concentrations in plasma that can be applied to various body fluids. The sensitivity was 2.5 ng/mL. The coefficients of variation were good both in intra- and inter-assay. Using this method to study the stability of an arginase preparation, we found that plasma arginase was stable for only 1 or 2 days even at temperatures as low as 4 degrees C. The mean plasma level was 41.0 +/- 3.3 ng/mL (mean +/- SE) in 143 normal subjects. There was no age difference in the general population and in the male group. However, in the female group, the plasma arginase level increased with age (p = 0.05). Its biological significance was unclear. As a whole, the ELISA method for the measurement of arginase concentration in the body fluid is convenient and reliable.

Modulation of in situ canine intrinsic cardiac neuronal activity by locally applied adenosine, ATP, or analogues

To determine whether adenosine or ATP can modify mammalian intrinsic cardiac neurons, these substances, as well as their analogues 5'-(N-ethylcarboxamido)-adenosine (NECA), N6-cyclopentyladenosine (CPA), and beta,gamma-methylene ATP (beta,gamma-mATP), were applied in microliter quantities adjacent to spontaneously active canine atrial ganglionated plexus neurons in 14 anesthetized open-chest dogs. Adenosine, NECA, and CPA induced neuronal responses, neuronal activity being either increased or decreased in 81, 86, and 86% of the sites tested, respectively. Cardiovascular responses were elicited by these agents in 21-31% of neurally active loci. ATP and beta,gamma-mATP elicited neuronal responses in 100 and 70% of tested loci, respectively. Associated cardiovascular responses were elicited by ATP and beta,gamma-mATP in 35 and 18% of the sites, respectively. After acute decentralization of the intrinsic cardiac nervous system, neuronal responses were elicited by purines in 73% of the previously active sites, while cardiovascular responses were either attenuated or eliminated. It is concluded that exogenous purine nucleosides and nucleotides can modulate the activity generated by in situ intrinsic cardiac neurons presumably by acting on P1 and P2 purinoreceptors. Furthermore, these data indicate that purine sensitive intrinsic cardiac neurons are involved in cardiac regulation.

Using ILIAD system shell to create an expert system for differential diagnosis of renal masses

Differential diagnosis of renal masses is an important and difficult process. A renal mass diagnostic system (RMDS) developed by using the ILIAD expert system shell has been created for diagnostic consultations and patient simulations. Seventy-two cases of renal mass have been tested on this system and the diagnostic accuracy was compared to that of residents. The overall diagnostic accuracy (75%) for renal masses is significantly better than second-year urological residents (60%) and not worse than urological chief residents (71%). The expert system also displays the cost of the diagnostic procedures so that the user can choose the most cost-effective diagnostic process. We conclude that this powerful renal mass diagnosis system developed by using ILIAD system shell can be used as a teaching, self-training and clinical tool for urological residents.

A comparison between vecuronium and atracurium in myasthenia gravis

We evaluated the effect of vecuronium bromide and atracurium besylate on the train-of-four response in the management of muscle relaxation in 20 patients with myasthenia gravis (MG) who were undergoing thymectomy. We confirmed the safe use of these two non-depolarizing muscle relaxants in MG patients. Vecuronium (0.04 mg.kg-1) demonstrated a lesser clinical duration than did atracurium (0.2 mg.kg-1) (38 +/- 19 vs 50 +/- 21 min, mean +/- s.e.mean). The recovery time for vecuronium patients was shorter than that for atracurium patients (22 +/- 18 vs 38 +/- 18 min), but the time until onset of neuromuscular blockade was longer with vecuronium (246 +/- 105 vs 107 +/- 103 s). During spontaneous recovery from neuromuscular relaxation, at T1/C of 25% and 100%, the train-of-four fade with vecuronium was significantly greater than that with atracurium (0.04 +/- 0.02, 0.16 +/- 0.03 vs 0.17 +/- 0.01, 0.83 +/- 0.03), suggesting that vecuronium had a greater prejunctional effect than did atracurium.

Modulation of in situ canine intrinsic cardiac neuronal activity by nicotinic, muscarinic, and beta-adrenergic agonists

To investigate whether microvolumes (< or = 10 microliters) of nicotinic, muscarinic, and beta-adrenergic agonists can modify intrinsic cardiac neuronal activity, nicotine, 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP), bethanechol chloride, and isoproterenol were separately administered adjacent to spontaneously active in situ epicardial neurons in 15 anesthetized dogs. Neuronal activity generated by 46 of 63 neurons was modified by these neurochemicals, with about half of the neurons affected by more than one agent. In association with these neuronal responses, cardiodynamic responses were elicited in 17 instances. When cardiac augmentation was elicited, it persisted after the administration of atropine but not of timolol. After cardiac decentralization, 40% of previously active neurons were still modified by local application of chemicals; cardiodynamic responses were elicited in nine instances. The activity of six units was modified by isoproterenol after subsequent administration of hexamethonium. These data confirm that intrinsic cardiac neurons possess nicotinic and muscarinic receptors and demonstrate that some intrinsic cardiac neurons also possess beta-adrenergic receptors. Furthermore, these data demonstrate that intrinsic cardiac neurons with nicotinic, muscarinic, and beta-adrenergic receptors are involved in cardiac regulation.

Cocultures of adult ventricular myocytes with stellate ganglia or intrinsic cardiac neurones from guinea pigs: spontaneous activity and pharmacological properties

OBJECTIVE

The aim was to develop long term primary cocultures of adult ventricular myocytes with autonomic neurones dissociated from stellate or intrinsic cardiac ganglia. This was to provide an experimental model for the investigation of the regulatory role of autonomic neurones with respect to cardiac myocyte function.

METHODS

Ventricular myocytes and stellate and intrinsic cardiac neurones were enzymatically dissociated from adult male guinea pigs and plated together on 13 mm cover slips; the cultures were maintained in an incubator for two to 10 weeks. The electrical properties of cultured myocytes and neurones were investigated by means of a conventional microelectrode technique and the spontaneous contractile activity of the myocytes was recorded by a video system. The electrical, contractile, and pharmacological properties of myocyte-neuronal networks were investigated by superfusing the cultures with various neuromodulators and blockers.

RESULTS

The electrical properties of the cultured myocytes and neurones were similar to those reported in other in vitro studies. Innervated and non-innervated cardiomyocyte cultures responded differently, however, to various pharmacological interventions. Spontaneous contractions were attenuated by tetrodotoxin (4 x 10(-7) M), beta adrenergic blockade, and nicotinic blockade more in cocultures than in cardiac myocyte cultures alone. On the other hand, the beta agonist isoproterenol increased the spontaneous beating in both types of cocultures more than in myocytes alone. The effects of the muscarinic agonist bethanechol and the muscarinic blocker atropine were not significantly different in innervated and non-innervated cultures. Nicotine induced either an increase or decrease in contractile rates of both cocultures and did not affect non-innervated myocyte cultures.

CONCLUSIONS

Cocultures of myocytes and autonomic neurones alter the responses of myocytes relative to cultures without neurones. The results suggest that functional contacts can be established between adult myocytes and dissociated neurones in primary cultures. Contractile rates of such myocyte cultures are influenced by the presence of neurones. Neurones innervating these cultures were modified by beta adrenergic, muscarinic, and nicotinic agents.

Amino acids modify activity of canine intrinsic cardiac neurons involved in cardiac regulation

The effects of amino acids on intrinsic cardiac neuronal activity identified in 10 anesthetized dogs were investigated. Local injection of small volumes (1-10 microliters) of the excitatory amino acids, glutamate (100 mM) and aspartate (10 mM), and the inhibitory amino acids, gamma-aminobutyric acid (GABA; 10 mM) and glycine (10 mM), modified the activity of 39 of 50 identified neurons. Spontaneous activity of eight neurons was modified by both excitatory and inhibitory amino acids. Cardiodynamic responses accompanied neuronal activity modification in 15 instances. After acute decentralization, repeat doses of amino acids altered the activity of 21 neurons and elicited cardiovascular responses in 7 instances. Neuronal and cardiovascular responses were elicited after atropine administration. Neuronal but not cardiac responses were elicited after subsequent timolol administration. In other animals, GABA but not other amino acids elicited neuronal and cardiodynamic responses after hexamethonium administration in decentralized preparations, indicating that non-nicotinic synapses were involved in some GABA-induced responses. These results demonstrate that excitatory and inhibitory amino acids can modify intrinsic cardiac neuronal activity such that, as a consequence, cardiac variables can be modified.

Lymph node metastasis in patients with adenocarcinoma of gastric cardia

BACKGROUND AND METHODS

Prospectively, a consecutive series of 42 patients undergoing extended radical total gastrectomies (R 3/4 lymph node dissection) for adenocarcinoma of the gastric cardia from January 1988 to June 1991 were studied. The aims of this study were to evaluate the status of lymph node metastasis and the relationship between the frequency of nodal involvement and the extent of the primary tumor invasion. The Japanese criteria was used for postoperative staging.

RESULTS

The incidence of operative morbidity and mortality in the series were 40.5% and 9.5%, respectively. Twenty-two (52%) of the patients had lymph node metastasis. For those patients, the most common sites of nodal involvement were the lesser curvature (72.7%), pericardiac (68.2%), left gastric artery (45.5%), left greater curvature (31.8%), splenic artery (31.8%), and the hilum (22.7%), inferior paraesophageal (18.2%), and diaphragmatic (18.2%) regions. Only one skip lymph node metastasis was discovered. In addition, no lymph node metastasis was found in the following areas: hepatoduodenal ligaments, mesenteric root, right paraadrenal, and subcardial lymph nodes.

CONCLUSIONS

The study's results demonstrate that there seemed to a correlation among the status of lymph node metastasis, tumor size, and the depth of tumor invasion. However, the depth of tumor invasion appears to be a more important factor than tumor size in influencing the status of lymph node metastasis. The local recurrence rate was 2.4%. Consequently, the authors recommend that for the tumor with mucosal invasion only, a relatively conservative lymphadenectomy may be sufficient, but for tumors that invade beyond the mucosal region, radical lymphadenectomy may be helpful in preventing local recurrence.

Peptidergic modulation of in situ canine intrinsic cardiac neurons

In order to determine which peptides are involved in modulating intrinsic cardiac neurons, angiotensin II, atrial natriuretic peptide, bradykinin, calcitonin gene-related peptide, enkephalin, neuropeptide Y, oxytocin, substance P, and vasoactive intestinal peptide dissolved in saline were administered individually by microinjection adjacent to spontaneously active canine intrinsic cardiac neurons. No neuronal or cardiac responses were elicited when saline was administered into active loci or when peptides were administered into loci with no spontaneous activity. Each peptide elicited neuronal responses when administered into active loci in most animals, bradykinin eliciting neuronal responses in every active locus studied. Concomitant cardiovascular responses were elicited in many cases when every peptide except atriopeptin was studied. After cardiac decentralization, neuronal and cardiovascular responses to repeat doses of peptides occurred with less frequency than before decentralization, implying that connections with central and other intrathoracic neurons can influence the function of peptide-sensitive intrinsic cardiac neurons. After atropine and timolol administration, cardiovascular, but not neuronal, responses to peptides were eliminated, indicating that cardiovascular responses were dependent upon efferent parasympathetic and sympathetic neurons. It is concluded that a number of neuropeptides may be involved in regulation of cardiac function by intrinsic cardiac neurons.

Long-term outcome of acupuncture in women with frequency, urgency and dysuria

Urodynamic measurements including cystometry, anal sphincter electromyography, urethral pressure profilometry and uroflowmetry were carried out on 21 female patients before acupuncture and at 1 and 3 years during follow-up. Follow-up ranged from 60 to 72 months (average 66.2 months). There was no significant difference in all urodynamic measurements before acupuncture and at the 1 year or 3 years follow-up. During follow-up, acupuncture at the Sp-6 point was performed in patients who had recurrence of symptoms of frequency, urgency and dysuria. The number of acupuncture treatments ranged from 2 to 8 times, with an average number of 4.8 times. A decrease of acupuncture treatments after 30 months was noted on 8 patients, but it was not statistically significant. We concluded that the long-term outcome of acupuncture at the Sp-6 point for women with frequency, urgency and dysuria was positive, but that the effect was temporary and repeated acupuncture was necessary to maintain beneficial effects.

Sudden bilateral hearing impairment in vertebrobasilar occlusive disease

BACKGROUND

Bilateral hearing impairment is rare in vertebrobasilar occlusive disease.

SUMMARY OF COMMENT

Between 1986 and 1991, we encountered seven patients (four men, three women; median age, 61 years; range, 46-71 years) who had sudden bilateral hearing impairment among 503 patients with vertebrobasilar occlusive disease. The main initial neurological symptoms were sudden bilateral hearing impairment, tinnitus, and vertigo. Acute labyrinthitis or Ménière's disease was the initial diagnosis until subsequent brain stem or cerebellar signs appeared. Brain stem auditory evoked potentials were abnormal bilaterally in six patients but had unilateral attenuation of the IV-V complex in the remaining one patient. Computed tomographic scans in all six patients showed multiple hypodense lesions in the brain stem and the cerebellum. Cerebral angiography showed complete occlusion on both vertebral arteries in one patient, occlusion on the left with small caliber on the right in another, and severe stenosis on both sides in a third. There was no opacification of internal auditory arteries in these three patients. The remaining patient had arteriosclerotic changes with faint opacification of the bilateral internal auditory arteries. Five patients had a poor prognosis, with locked-in state in four and severe truncal ataxia in one.

CONCLUSIONS

We conclude that sudden bilateral hearing impairment in vertebrobasilar occlusive disease is more common than previously recognized and that it may indicate a grave prognosis.

Effects of transient coronary artery occlusion on canine intrinsic cardiac neuronal activity

In order to further elucidate the regulatory function of canine epicardial neurons, the effects of transient coronary artery occlusion on their spontaneous activity was studied. Fifty-eight individual, spontaneously active units were identified by means of their action potential configurations in specific loci of atrial and ventricular epicardial fat of 10 anesthetized dogs. The activity of 49 of the units was modified by one minute of coronary artery occlusion. Twenty-four of the 49 responding units exhibited increased activity and 37 decreased activity during coronary artery occlusions. Activity changes were sometimes, but not always, associated with decreased left ventricular intramyocardial systolic pressure. During reperfusion, the activity of 6 units was increased compared to control levels, even though ventricular pressures remained the same. Following acute decentralization, 48% of previously active units generated spontaneous activity; the activity of 89% of these was altered during coronary artery occlusion despite the fact that overall cardiodynamics were unchanged. Following hexamethonium administration, the activity generated by 9 of 10 spontaneously active units was modified by coronary artery occlusion. It is concluded that transient coronary artery occlusion can modify the activity generated by intrinsic cardiac neurons, such modification involving central and peripheral neuronal interactions.

Subcapsular hematoma of spleen--a complication following extracorporeal shock wave lithotripsy for ureteral calculus

Splenic trauma with hematoma following extracorporeal shock wave lithotripsy (ESWL) is very rare. We reported a case of subcapsular hematoma of spleen with impending rupture following ESWL for ureteral calculus. This case was noted to have liver cirrhosis and splenomegaly, and received a total of 2000 shock waves under 18 kilovoltage. The subcapsular hematoma occurred 2 months later. Splenectomy was undertaken for a symptomatic huge subcapsular hematoma and thrombocytopenia. We reviewed the literature and concluded that portal hypertension with severe coagulopathy are contraindications for ESWL, even in case with ureteral calculus.

Anomalous systemic arterial supply to normal basilar segments of the lower lobe of the left lung

A 38-year-old man with an anomalous systemic arterial supply from the descending thoracic aorta to the normal basilar segments of the left lower lobe experienced symptoms of progressive exertional dyspnea. Although the pulmonary parenchyma was normal, there was no pulmonary arterial supply to the basilar segments of the left lower lobe. Left lower lobectomy was performed because of worsening left-to-left shunt. Aortography and pulmonary arteriography form the cornerstone for diagnosis, but a less invasive diagnostic method with less patient suffering is high-resolution computed tomography, which might replace bronchography for accurate evaluation of the distribution and patency of the bronchial tree and delineation of the characteristic "Medusa's hair"-like anomalous vascular supply penetrating into the nearly normal pulmonary parenchyma.