Congenital diaphragmatic hernia--a review of pre- and postoperative chest radiology

Delayed-type hypersensitivity responses against bovine leukemia virus (BLV) envelope glycoprotein (gp60) were induced in the skin of sheep vaccinated with recombinant vaccinia virus (RVV) expressing BLV glycoprotein. The lesions were characterized by marked infiltration of lymphocytes, slight migration of neutrophils, eosinophils, and macrophages in the dermis to hypodermis, and partial intercellular edema in the reticular layer. Immunohistochemical analysis with monoclonal antibodies demonstrated that the lymphocytic infiltrates consisted mainly of CD8+ T cells (53.7-55.8% at 48 hours post-challenge of BLV), CD4+ T cells (24.7-26.7%), and B cells (11.5-16.9%). The role of CD4+ and CD8+ T cells in suppressing BLV growth in RVV-vaccinated animals is discussed.     

Injuries to the phrenic nerve resulting in diaphragmatic paralysis with special reference to stretch trauma

The effectiveness of purines and purine analogues as inducers of erythroid differentiation in cultured murine erythroleukemia cells has been investigated. These cell lines have previously been shown to differentiate in vitro in response to dimethylsulfoxide (DMSO) and a number of other polar solvents. Two purine analogues, 6-thioguanine and 6-mercaptopurine, as well as the naturally occuring purine, purine, hypoxanthine, are shown to be extremely potent inducers. 6-Thioguanine is effective at a concentration of 0.06 mM, 750 fold lower than the DMSO concentration required for equivalent induction. 6-Mercaptopurine and hypoxanthine are effective inducers at a concentration of approximately 2 mM. Accumulation of globin mRNA was monitored during induction with purine inducers and shown to be similar in amount to globin mRNA levels reached in DMSO-induced cultures. Induction of differentiation by all three compounds follows a similar time course to induction with DMSO. All three compounds are potent inducers of HGPRT (hypoxanthine-guanine phosphoribosyltransferase)-negative cell lines; hence incorporation of purines into DNA is not required for induction of differentiation. Comparison of these compounds with other purines and purine analogues suggests a high degree of specificity in their interaction with a cellular target.     

Diaphragm EMG measured by cervical magnetic and electrical phrenic nerve stimulation

The purpose of the study was to compare electrical stimulation (ES) and cervical magnetic stimulation (CMS) of the phrenic nerves for the measurement of the diaphragm compound muscle action potential (CMAP) and phrenic nerve conduction time. A specially designed esophageal catheter with three pairs of electrodes was used, with control of electrode positioning in 10 normal subjects. Pair A and pair B were close to the diaphragm (pair A lower than pair B); pair C was positioned 10 cm above the diaphragm to detect the electromyogram from extradiaphragmatic muscles. Electromyograms were also recorded from upper and lower chest wall surface electrodes. The shape of the CMAP measured with CMS (CMS-CMAP) usually differed from that of the CMAP measured with ES (ES-CMAP). Moreover, the latency of the CMS-CMAP from pair B (5.3 +/- 0.4 ms) was significantly shorter than that from pair A (7.1 +/- 0.7 ms). The amplitude of the CMS-CMAP (1.00 +/- 0.15 mV) was much higher than that of ES-CMAP (0.26 +/- 0.15 mV) when recorded from pair C. Good-quality CMS-CMAPs could be recorded in some subjects from an electrode positioned very low in the esophagus. The differences between ES-CMAP and CMS-CMAP recorded either from esophageal or chest wall electrodes make CMS unreliable for the measurement of phrenic nerve conduction time.     

Effects of carotid Body chemoreceptor stimulation by 5-HT on phrenic nerve activity and ventilation in the rabbit

Effects of carotid body chemoreceptor stimulation by 5-hydroxytryptamine (5-HT) on the phrenic nerve activity and ventilation were studied by injecting it into the external carotid artery of the rabbits. 5-HT induced an immediate and transient increase of ventilatory rate which became more pronounced with increasing the dose, but it was accompanied by decreases in integrated phrenic nerve activity and tidal volume. The excitatory response was followed by an inhibition in 35% of the experiments. The 5-HT-induced excitation was unaffected by pretreatment with atropine and mecamylamine, but it was completely blocked by tetrodotoxin (TTX) which failed to inhibit the excitation induced by NaCN. Prior administration of atropine abolished the inhibitory effect of 5-HT and the ventilatory excitation induced by baroreceptor stimulation. It may be suggested that the excitation induced by 5-HT results from stimulation of chemoreceptor nerve endings, whereas the inhibition is probably due to its action on baroreceptor nerve endings.     

Chronic stimulation of the left vagal nerve in children: effect on swallowing

PURPOSE: To learn whether stimulation of the left vagal nerve would influence swallowing. METHODS: Eight children receiving intermittent left vagal nerve stimulation (VNS) for their pharmacoresistant epilepsy underwent barium swallow studies with their generators off, on, and at maximally tolerated settings. RESULTS: Laryngeal penetration of barium was present in three patients without stimulation, and was caused by VNS in one other patient. Aspiration never occurred. CONCLUSIONS: Stimulation of the left vagal nerve under conditions used to treat epilepsy does not cause aspiration.     

A computer-based reporting system in radiology of the chest

The aim of this study was to compare our computer-aided report writing system to standard techniques. A computer-aided reporting system for reporting on chest X-rays was developed and linked with a UNIX-based radiology information system. The reporting system consists of different text modules which can be composed to a complete radiological report. The quality of the report, the system's efficiency, flexibility and availability at the radiology information system (RIS), as well as its acceptance by the users, were criteria we took as a basis of evaluation. Acceptance and flexibility of the system were tested by assessing necessary changes and additions performed to text modules and by subjective evaluation. The time spent on working with the reporting system was evaluated by performing a time-analysis study comparing the new system to the two conventional methods, the tape system and handwriting. On average, the readers needed 22.6 text modules for each report. For the users the most important advantages of the new system are that primarily fewer changes to or additions to the text are necessary, and when they cannot be avoided they can be performed more easily. In comparison with the tape system and handwritten reports, it took on average two and a half to three times longer to report on a chest X-ray. The printed report had left the department within 6.4 h using the tape system within 0.4 h when handwritten and within 1.4 h when recorded by the reporting system. The completeness of the set of modules and the logical order were positively assessed by the users. The demand of time for reporting increases, but the final report is available sooner.     

Early neurologic manifestations of minimal brain dysfunction in children]

The authors studied 207 children with minimal cerebral dysfunctions. Among this contingent 132 were followed-up from the moment of birth and subsequently during 8-10 years. It was demonstrated that already at the early stages of development certain neurological signs can be detected: somato-vegetative disorders, changes of the muscular tone, a hypertensive syndrome. In some of the children there was a retardation of psychomotor functions and prespeech development. One of the important goals at the present time is the elaboration of preventive measures of minimal cerebral dysfunctions in children with perinatal brain lesions.     

Peripheral sensory nerve dysfunction in children and adolescents with type 1 diabetes mellitus

The aim of the present study was to investigate peripheral sensory nerve function in diabetic children and adolescents without neurological symptoms. Ninety-two children and adolescents with Type 1 (insulin-dependent) diabetes mellitus (mean +/- SD age: 14.2 +/- 2.1 years, diabetes duration: 5.8 +/- 3.0 years) and 80 healthy control subjects (age: 13.8 +/- 2.2 years) matched for age, sex, body mass index, and height standard deviation score were involved in the study. Using a sine-wave transcutaneous stimulator, current perception threshold (CPT) testing at 2000, 250 and 5 Hz was performed on the left median and peroneal nerves. Diabetic children had increased CPT at 2000 Hz on both nerves as compared to the control group (median (interquartile range), median nerve: 2.43 (2.20-3.43) vs 1.80 (1.51-2.60) mA, p = 0.02; peroneal nerve: 3.51 (2.81-4.82) vs 2.70 (2.04-3.70) mA, p = 0.01). Twenty-one (23%) of patients had CPT values higher than that of any healthy individual. Of these, elevated CPT was observed in 9 (9.8%) patients on the median nerve, in 8 (8.7%) patients on the peroneal nerve, and in 4 (4.3%) patients on both median and peroneal nerves. Using multiple logistic regression analysis, worse long-term metabolic control and advanced puberty were independently predictive of peripheral sensory nerve dysfunction as the dependent variable (adjusted OR (95% CI): 3.4 (1.2-6.2), p = 0.01, and 2.8 (1.1-5.6), p = 0.03, respectively). In conclusion, evidence of peripheral sensory nerve dysfunction is not rare in children and adolescents with diabetes and can be demonstrated by CPT testing in asymptomatic patients. Poor metabolic control is a risk factor for such subclinical neuropathy, and pubertal development may be involved in the pathogenesis of diabetic peripheral neuropathy.     

Paired phrenic nerve stimuli for the detection of diaphragm fatigue in humans

The transdiaphragmatic pressure (Pdi) elicited by paired bilateral phrenic nerve stimulation may be viewed as the sum of the Pdi values produced by the first (t1) and second (t2) stimulus. The Pdi at t2 (P[di,t2]) is a function of the interstimulus interval. A reduction in the ratio obtained by dividing Pdi,t2 at 10 Hz (P[di,t2,10]) by Pdi at 100 Hz (P[di,t2,100]) (t2(10:100)) has been proposed as a test of low frequency diaphragm fatigue. The aim of the present study was to establish whether this change could also be detected using paired cervical magnetic nerve stimulation (pCMS), and whether t2(10:100) was influenced by lung volume. We studied healthy subjects at functional residual capacity (FRC), at 0.5 and 1.0 L below FRC, and at 0.5, 1.0 and 1.5 L above FRC. The subjects were then subjected to a fatiguing protocol (2 min of maximal isocapnic ventilation (MIV)). Studies were repeated at FRC 20 and 60 min after MIV and between these times at 1.0 L below and 1.5 L above FRC. In the unfatigued state, t2(10:100) had a negative relationship with increasing lung volume (r2=0.98, p=0.002). After MIV there was a fall in the Pdi elicited by a single stimulus (mean fall at 20 min 17.9% and at 60 min 14.6%, p<0.03 for both). t2(10:100) fell by a mean 28.1% after 20 min and mean 22.9% at 60 min (p<0.03 for both). This change was mainly mediated by a fall in the P[di,t2,10]. The t2(10:100) was not able to distinguish between fatigue and acute hyperinflation. We conclude that paired cervical magnetic nerve stimulation may be used to detect low frequency diaphragm fatigue but that it remains important to control for lung volume.     

Mediastinal lipoblastoma involving the left innominate vein and the left phrenic nerve

Lipoblastoma, a rare tumor of childhood, was first described by Vellois and associates in 1958. The extremities are the most common location for this tumor. Mediastinal lipoblastoma is exceedingly rare, with only four cases reported in the English-language literature. The authors report a case of mediastinal lipoblastoma in a 6-year-old girl, which, in contrast to previously reported cases, presented late in childhood and included sacrifice of the left innominate vein and phrenic nerve for successful resection.     

Normal appearance and size of the diaphragmatic crura in children: CT evaluation

PURPOSE: The objectives of the study were to document the normal CT appearance and size of the crura of the diaphragm in children. MATERIALS AND METHODS: The CT scans of 80 children (0-15 years) were reviewed. The children were divided into eight age groups. The maximal transverse diameters of the right and left crura were measured. They were normalized by comparison with the transverse and anterior-posterior diameters of the 12th thoracic vertebra (T12) and the transverse abdominal diameter at T12. The crura were also evaluated as to whether their contour was smooth or nodular. RESULTS: The diaphragmatic crura of smaller children appear large, relative to body size and the diameters of the T12 vertebral body, compared with those in older children. Crural width does not increase significantly with age. Additionally, the crura were found to have a greater tendency to be nodular in appearance in children under the age of 5 years than in older children. CONCLUSION: Diaphragmatic crura are more nodular and larger relative to body size in younger children.     

The cortical representation of somatosensory evoked potentials of the phrenic nerve

Parasitic third-stage larvae of the sheep abomasal nematode Haemonchus contortus develop and molt in vitro to the fourth stage (L4) in 48-72 hr, at which time they begin feeding. Coincident with the third molt, larvae begin to secrete significant amounts of protein into culture fluids, including a zinc metalloproteinase. This culture-derived zinc metalloproteinase differs from a previously described metalloproteinase from infective third-stage larvae (L3[2M]), which mediates the ecdysis process. These differences include time of expression, molecular mass, and substrate specificity. The purified proteinase, from cultures of L4, has a molecular weight of approximately 46 kDa, functions as an endopeptidase, and digests several native proteins of host origin including fibrinogen and fibronectin.     

Hodgkin's disease in children: clinico-roentgenologic features of the lesion in the chest

The roentgenologic features of Hodgkin's disease were studied in 105 patients under 14 years of age. The mediastinal and hilar nodes were involved in 64.7% of patients. Some consistency of extent and pattern of disease was observed in that mediastinal lymphatic lesions could be associated with cervico-supra-clavicular and retroperitoneal lesions. There was lung infiltration in 14.3% of patients and the frequency of this lesion dependent on the histological type. It was commoner in nodular sclerosis, mixed cellularity and lymphocytic depletion. Lung infiltration usually developed in continuity with the lymphatic gland lesion and only rarely in a metastasis-like form.