Physiological response properties of cells labeled intracellularly with horseradish peroxidase in cat ventral cochlear nucleus

To determine the correspondence between anatomical and physiological cell types in the ventral cochlear nucleus of the cat, intracellular injections of horseradish peroxidase were made into cells whose extracellular and intracellular responses to sound had been studied. Three identified cells responded to a short tone burst at their characteristic frequencies with an onset pattern. This pattern is characterized by a strong response to the onset of the stimulus. One was an octopus cell. The second cell, located in the octopus-cell area, was a giant cell with a few somatic spines and thin tapering dendrites; the intracellular record revealed that even in the absence of sound it received continuous synaptic input, while tones at characteristic frequency produced a sustained depolarization. A third cell, which had an onset response at low intensities and a chopper response at high intensities, was a stellate cell located in the intermediate acoustic stria with dendrites oriented parallel to the fiber tract. This cell had an unusually broad dynamic range in response to changes in intensity. Two cells with transient chopper response patterns were stellate cells in the posteroventral cochlear nucleus with many branched and beaded dendrites. Three cells with more sustained chopper response patterns were stellate cells in the anteroventral cochlear nucleus with fewer, less-branched, smooth dendrites. Two cells with primarylike responses to tones were bushy cells with numerous short, thin, highly branched dendrites in the posterior division of the anteroventral cochlear nucleus. Intracellular responses to tones at the characteristic frequency consisted of large brief depolarizations, which were not sustained. Another cell, which responded to tones in a phase-locked fashion, was also located in the anteroventral cochlear nucleus. It was a small, stellate cell with relatively few, smooth dendrites. The labeled cells largely support previous attempts at physiological-morphological correlations: (1) bushy cells exhibit primarylike pattern; (2) stellate cells exhibit chopper patterns; and (3) octopus cells exhibit an onset pattern. It was also demonstrated that more than one cell type can exhibit a particular response pattern.     

Nutrition following gastric operations for morbid obesity.

Nutritional status after 238 gastric operations designed to reduce caloric intake and body weight to within 30% of ideal was assessed by measuring body composition using the multiple isotope dilution technique. Body cell mass (BCM) and body fat were quantitated before and at 24 months after operation. Malnutrition was defined as a total exchangeable sodium (Nae) to total exchangeable potassium (Ke) ratio greater than 1.22. Data were collected on 96 patients. All had lost a mean of 26% of preoperative weight by 24 months. Significant malnutrition occurred in 47 patients whose Nae/Ke ratio ranged from 1.23 to 2.17 (1.45 +/- 0.03). There was a 34% reduction in body fat. The malnourished patients lost 10% more BCM by 24 months than did the normally nourished group. Malnutrition resolved as the stoma enlarged in 19 patients, and dietary counselling helped eight patients. Eighteen patients required reoperation to establish a larger orifice, and endoscopic dilatation was successful in two patients. Administration of a liquid diet via the gastrostomy was required for prolonged periods in some malnourished patients. Seventeen patients who had lost weight rapidly over a short time had low vitamin B12, thiamine, and serum and RBC folate levels. One patient had a markedly decreased serum thiamine level with neuropathy. Symptoms of weakness, easy fatigability, and lassitude were found in the malnourished patients. Low thiamine and serum folate levels were also seen in patients ingesting a liquid diet of 750 kcal with a standard multivitamin supplement. Malnutrition was not seen in these patients. In the 49 patients who remained well nourished, BCM decreased by 19%, but the Nae/Ke remained normal. Weight loss was well tolerated, and no patients required reoperation or supplemental liquid diet to increase caloric or protein intake. The degree of malnutrition in patients after gastric operations is as great as following intestinal bypass but is not associated with liver failure. Malnutrition with vitamin deficiency is a great potential hazard in patients who undergo intake-limiting operations, especially if the goal of the operation is to restore near-normal weight. Current operations are successfully designed to maintain a small orifice size, so that the risks of malnutrition are likely to increase in the future.     

Detection of steroid hormone receptors in patients with mastopathies and fibroadenomas

Estradiol and progesterone receptors have been determined in 74 women with mastopathy and 33 women with fibroadenomas in the period from 1986-1988. Mastopathy was classified according to Prechtel (stage I-III). A negative steroid-hormon-receptorstatus (less than 10 fmol/mg protein) was predominant in the group with Prechtel I and II. In our study the progesterone receptor was detectable more frequently than the estradiol receptor in patients with mastopathy or fibroadenomas.     

Pancreatic transplant imaging

Forty-four clinical episodes of suspected (pancreas) transplant rejection in 17 pancreatic transplantation patients were reviewed retrospectively. The clinical impression of acute graft rejection, chronic rejection, or nonrejection in each episode was correlated with the results of 19 nuclear medicine, 12 ultrasound (US), and 44 magnetic resonance (MR) imaging studies. US was found to be a moderately sensitive (82%) method of detecting graft rejection. US also was effective in identifying intra- and peripancreatic fluid accumulations. Nuclear medicine imaging was also a sensitive technique (86%) and the only modality that provided physiologic information regarding graft perfusion. MR imaging allowed correct prediction of the presence or absence of graft rejection in 39 of 44 cases (sensitivity, 100%; specificity, 76%) and was an effective means of detecting pathologic fluid collections. Nuclear medicine, US, and MR imaging are all believed to be sensitive methods of detecting graft rejection and are complementary adjuncts to the clinical evaluation of pancreatic transplants.