Validation of esophageal pressure occlusion test after paralysis

Measurements of respiratory mechanics are frequently made in ventilated infants and children. Esophageal pressure measurements (P_es using a balloon on a catheter have been used to partition the respiratory mechanics into lung and chest wall components. Appropriate positioning of this balloon is crucial to obtain accurate estimates of pleural pressure. Traditionally, in spontaneously breathing subjects the balloon position is assessed with an occlusion test. In ventilated subjects, it is not always possible to perform an occlusion test prior to paralysis, and even if such a test is performed it may not be relevant under conditions of positive pressure ventilation. We have assessed a positive pressure occlusion test that is suitable for paralyzed subjects. By occluding the airway opening and applying gentle pressure to the abdomen or rib cage, positive swings in pressure can be measured by both P_es and airway opening pressure (P_ao). We compared traditional occlusion tests measured in 16 spontaneously breathing puppies to the positive pressure occlusion test performed after paralysis. In 2 pups we were unable to obtain a reasonable traditional occlusion test (>15% difference between P_es and P_ao) but we obtained 10 traditional occlusion tests in each of the remaining 14 pups (2.1–14 kg). In 11 of these animals Ape, was within 10% of P_ao. This compared well to positive pressure occlusion test using abdominal pressure performed after paralysis, where Apes was within 10% of ΔP_ao in 10 animals. In 9 of these pups occlusion tests were also performed by applying pressure on the rib cage, where ΔP_es was within 10% of ΔP_ao in 6 animals. These results suggest that it is possible to perform accurate occlusion tests in paralyzed subjects by abdominal or rib cage compression with the airway occluded. Pediatr Pulmonol. 1994; 17:56–62. © 1994 Wiley-Liss, Inc.     

Relationships between Responsiveness of the Bronchi to Acetylcholine and Cyclic AMP Response of Lymphocytes to Beta1- and Beta2-Adrenergic Receptor Stimulation in Patients with Asthma

Decreased response of beta-adrenergic receptor has been considered to he one of the causes of increased responsiveness of the bronchi in asthma. Since beta-adrenergic receptor has two subtypes, beta₁ and beta₂, and the bronchodilating effect of beta stimulants is mediated by beta₂-receptor, responsiveness of the bronchi is expected to correlate to the cyclic AMP response of lymphocytes to a beta₂-stimulant. Responsiveness of the bronchi was expressed as respiratory threshold to acetylcholine (RT-Ach), which was the minimal concentration of acetylcholine solution to cause an initial decrease of FEV₁ of more than 20% of the baseline value. Beta₁ and heta₂-responses were expressed as the increments of cyclic AMP content of 10⁶ lymphocytes incubated with norepinephrine (beta₁-stimulant) and salbutamol (beta₂-stimulant).
RT-Ach showed a significant correlation with the beta₂-cyclic AMP response of lymphocytes, but not with the beta₁ -response among patients with asthma. Sixteen symptomatic patients on continuous beta-stimulants showed lower RT-Ach value and diminished beta₂-receptor activity of lymphocytes compared with 14 patients in remission. These results suggest that selective beta₂-adrenergic blockade may he one of the causes of bronchial hypersensitivity in asthma, though it should be noted that in this study beta-adrenergic responses were examined in lymphocytes and were compared with the responsiveneness of the bronchi. Possible beta-receptor subsensitivity induced by administration of beta-stimulants is discussed.     

Critical spectral regions for vowel identification

The first two formant frequencies (F1 and F2) are the cues important for vowel identification. In the categorization of the naturally spoken vowels, however, there are overlaps among the vowels in the F1 and F2 plane. The fundamental frequency (F0), the third formant frequency (F3) and the spectral envelope have been proposed as additional cues. In the present study, to investigate the spectral regions essential for the vowel identification, untrained subjects performed the forced-choice identification task in response to Japanese isolated vowels (/a, o, u, e, i/), in which some spectral regions were deleted. Minimum spectral regions needed for correct vowel identification were the two regions including F1 and F2 (the first and fourth in the quadrisected F1-F2 regions in Bark scale). This was true even when phonetically different vowels had a similar combination of F1 and F2 frequency components. F0 and F3 cues were not necessarily needed. It is concluded that the relative importance in the spectral region is not equivalent, but weighted on the two critical spectral regions. The auditory system may identify the vowels by analyzing the information of the spectral shapes and the formant frequencies (F1 and F2) in these critical spectral regions.     

Effects of growth hormone treatment on thyroid function in pediatric patients with Prader–Willi syndrome

It is unclear whether hypothyroidism is present in patients with Prader–Willi syndrome (PWS). This study aimed to clarify the state of the hypothalamic–pituitary–thyroid axis and the effects of growth hormone (GH) treatment on thyroid function in pediatric patients with PWS. We retrospectively evaluated thyroid function in 51 patients with PWS before GH treatment using a thyroid‐releasing hormone (TRH) stimulation test (29 males and 22 females; median age, 22 months). We also evaluated the effect of GH therapy on thyroid function by comparing serum free triiodothyronine (fT3), free thyroxine (fT4), and thyroid stimulating hormone (TSH) levels at baseline, 1 year, and 2 years after GH therapy. TSH, fT4, and fT3 levels were 2.28 μU/ml (interquartile range [IQR]; 1.19–3.61), 1.18 ng/dl (IQR; 1.02–1.24), and 4.02 pg/dl (IQR; 3.54–4.40) at baseline, respectively. In 49 of 51 patients, the TSH response to TRH administration showed a physiologically normal pattern; in two patients (4.0%), the pattern suggested hypothalamic hypothyroidism (delayed and prolonged TSH peak after TRH administration). TSH, fT4, and fT3 levels did not change significantly during 1 or 2 years after GH treatment. The TSH response to TRH showed a normal pattern in most patients, and thyroid function did not change significantly during the 2 years after initiating GH treatment.     

Immunocytochemical evaluation abl-Gene products in Leukemic Cell Lines

We raised monoclonal antibody (MAb) against a synthetic oligopeptide corresponding to a portion of the predictedv-abl protein sequence (379–390). This MAb reacted with all of theabl-gene products (pl45^c-abl, pl50^c-abl and 210^bcr-abl fused protein) and was not specific for any one of them. Immunocytochemically, we investigated the expression and localization of theabl-gene products in various leukemic cell lines. Positive immunoreactions were observed in Ph¹ positive leukemic cell lines (K562 and KU-812) and erythro-leukemic cell lines (HEL and K3D) and were located on the cell membrane. Electron microscopically, a different distribution pattern was observed among the cell lines: linear and almost even in Ph¹ positive leukemic cell lines, whereas spotted or budding-like in erythroleukemic cell lines. Ph¹ translocation produces p210^nbcr-abl fused protein with not only altered autophosphorylation activities but also altered subcellular distribution patterns.     

Duodenal gastric heterotopia,sporadic or fundic gland polyp-associated,frequently carries β-catenin mutation

Duodenal gastric heterotopia (DGH) is a benign asymptomatic condition assumed to be of congenital origin. Since DGH is often associated with fundic gland polyps (FGPs) that frequently carry a somatic β-catenin gene mutation, we examined whether DGH, either sporadic or FGP-associated, is attributable to alterations of the Wnt/β-catenin pathway. Genetic analysis revealed frequent somatic β-catenin gene mutations in DGH; some of which showed the same mutation pattern as coexisting FGPs. All missense mutations were confined to codons 32, 33, and 37. No such mutations were observed, however, in any of the specimens from focal gastric foveolar metaplasia (GFM). Therefore, DGH is not a mere congenital lesion due to aberrant migration of normal gastric mucosa or a simple reactive metaplasia after regenerative stimuli of the duodenal mucosa, but a distinct condition based upon molecular genetic changes in the Wnt/β-catenin pathway.     

The Prognostic Nutritional Index Predicts Long-term Outcomes of Gastric Cancer Patients Independent of Tumor Stage

Purpose

The aim of this study was to investigate the impact of the prognostic nutritional index (PNI) on the long-term outcomes in gastric cancer patients.

Methods

This study reviewed the medical records of 548 patients with gastric cancer who underwent gastrectomy. The PNI was calculated as 10 × serum albumin (g/dl) + 0.005 × total lymphocyte count (per mm³). The receiver operating characteristic (ROC) curve analysis was performed to determine the cutoff value of the PNI. The multivariate analysis was performed to identify the prognostic factors.

Results

The mean PNI was significantly lower in patients with T3–T4 tumors (P < 0.001) and lymph node metastasis (P < 0.001) than in those without such factors. Patients who had a postoperative complication had a lower mean PNI than those without (P = 0.023). When the ROC curve analysis was performed, the optimal cutoff value of the PNI for predicting the 5-year survival was 48. In the multivariate analysis, a low PNI was an independent predictor for poor overall survival (P < 0.001). In the subgroup analysis, the overall and relapse-free survival rates were significantly lower in the PNI-low group than in the PNI-high group among patients with stage I and stage III disease.

Conclusions

The PNI is a simple and useful marker for predicting the long-term outcomes of gastric cancer patients independent of the tumor stage. Based on our results, we suggest that the PNI should be included in the routine assessment of gastric cancer patients.     

Hodgkin's disease of the thoracic vertebrae

Background contextHodgkin's disease rarely occurs in the spine, which is usually a setting for the advanced form of the disease.PurposeTo describe an unusual case of isolated, primary spinal Hodgkin's disease and to draw attention to this disease as a possible diagnosis in patients with mixed inflammatory cell infiltrate lesions located in the thoracic spine.Study design/settingA case report of a 28-year-old woman who presented with back pain and progressive weakness in the lower extremities as a result of spinal cord compression from Hodgkin's disease of the thoracic vertebrae.MethodsWe report a new case of spinal cord compression resulting from Hodgkin's disease of the thoracic vertebrae. Decompression surgery was performed in the patient, followed by antibiotic treatment.ResultsAntibiotic therapy temporarily improved inflammation and fever. However, magnetic resonance imaging (MRI) evaluation showed that the inflammatory reaction in the lesion was not completely resolved. The disease progressed and later investigations revealed Hodgkin's disease, which improved with a course of chemotherapy and radiation.ConclusionsHodgkin's disease should be considered in the differential diagnosis of spinal neoplastic lesions with clinical features similar to spondylitis. Because MRI evaluation showed that the vertebral disc was maintained in this case, the presence of a tumor rather than inflammation should have been suspected.