Adenocarcinoma of the lower esophagus. A disease primarily of white men with Barrett's esophagus

Sex and racial predilection, social history, and histology were analyzed in a biopsy-proven adenocarcinoma of the lower esophagus/esophagogastric junction collected over a 5-year period in two teaching institutions with different patient populations. Adenocarcinoma occurred in 11% of patients with biopsy-proven esophageal cancer. The disease occurred only in males at one center, and in a 7:1 ratio of males to females at the other center. Clear racial predilection was seen, since 12 of 13 patients with adenocarcinoma of the esophagus were white, whereas less than 20% of patients with squamous carcinoma of the esophagus were white. The finding of Barrett's epithelium in eight of the 13 cases strongly supports the theory that in white males, Barrett's epithelium is a precursor lesion of adenocarcinoma of the esophagus/esophagogastric junction.     

Rapid desensitization of the acute stimulatory effects of nicotine on rat plasma adrenocorticotropin and prolactin

The dose of nicotine and the frequency of its administration appear to be essential determinants of its action on multiple systems including the neuroendocrine regulation of the adrenocorticotropin (ACTH)-corticosterone and prolactin (PRL) axes in the rat. Because desensitization to the acute depressive effects of nicotine has been observed after both acute and chronic administration, these investigations assessed whether desensitization to the stimulative effects of nicotine on ACTH and PRL secretion occurs with repetitive dosing. Extensive dose and time course experiments showed that nicotine rapidly elevates rat plasma ACTH and PRL levels with a threshold dose between 0.1 to 0.25 mg/kg b.wt. i.p. After the stimulation of PRL, levels became significantly depressed. Desensitization to the acute stimulatory effects of nicotine on both hormones was induced by a single dose of nicotine (0.5 mg/kg). One hour later nicotine (1.0 mg/kg) failed to significantly stimulate PRL levels and resulted in a modest increase of ACTH. Desensitization was maximal by 1 hr after the first dose and persisted for at least 6 hr. Adrenalectomy, performed to eliminate corticosterone-induced negative feedback, did not enhance PRL responsiveness to a second dose of nicotine but it partially restored the ACTH response. Pretreatment with corticosterone also failed to modify the PRL response to a single dose of nicotine whereas it partially suppressed the ACTH response. Rapid desensitization to the acute stimulatory effects of nicotine on plasma PRL is independent of glucocorticoid negative-feedback whereas desensitization of the ACTH response is modestly dependent.     

The cytochromes P-450 concentrations in microsomes of liver, kidney and duodenal mucosa of the camel, sheep and goat

The concentration of microsomal cytochromes P-450, and of protein in the homogenate, cytosol and microsomes were measured in the liver, kidney and duodenal mucosa of healthy well-fed male and female camels, sheep and goats. For comparison, data from the liver of male and female rats were also obtained. The protein concentrations in the tissues of adult animals were broadly similar in the four species. The concentration of cytochromes P-450 was highest in the liver, followed by the kidney, then the duodenal mucosa in all the species. No cytochromes P-450 were detected in the tissues of immature (less than 1 mo) male goats, whereas the female goat had the highest concentrations of these enzymes in the liver and kidney when compared with the respective tissues in the other species studied. Males had higher activity of cytochromes P-450 than females in the three tissues, except in the duodenal mucosa of sheep, where males had lower activity than females. In camel liver and sheep kidney, the amount of cytochromes P-450 were similar in the two sexes. The present results suggest that the mature female goat is the species best equipped to handle xenobiotics which are detoxified by the cytochromes P-450 and other drug metabolizing enzymes in diseased or malnourished animals is suggested as these two conditions are known to modify drug metabolizing enzymes.     

Aseptic bone necroses as a late complication following successful treatment of leukemias and severe aplastic anemia

Aseptic bone necrosis is a well known complication after corticosteroid treatment in adults and several hundred cases have been reported. Alterations in fat metabolism with vascular occlusion due to fat embolization, as well as microtraumata and osteoporosis are discussed as etiologic factors. In contrast, aseptic bone necrosis in relation to corticosteroid treatment is rare in children and adolescents. We therefore report 3 patients, aged from 10 to 18 years, suffering from severe aplastic anemia, meningeal relapse after acute lymphocytic leukemia and acute myelocytic leukemia respectively, who developed aseptic bone necrosis 6, 11, and 20 months following the onset of corticoid therapy. The patients survive from 28+ to 50+ months after diagnosis of their initial hematologic disease, as it can be expected today for increasing numbers of patients. We therefore believe, that aseptic bone necrosis may represent a serious therapy related complication and suggest that, diagnostic examination in patients with suspicious complaints of the hip, shoulder or knee should also exclude the possibility of a bone necrosis after leucemic relapse has been ruled out. Since radiological changes only develop several weeks to months after the onset of the clinical symptoms and because of the disabling consequences for patients, misdiagnosed at the beginning, a 99 technetium bone scan should be done as early as possible. Corticosteroids, despite their serious side effects are still being considered as a important part of hematologic therapy and are not being omitted in the near future, so that the earliest possible diagnosis of bone necrosis will remain of great importance.(ABSTRACT TRUNCATED AT 250 WORDS)     

Syrup of ipecac availability: before and after a poisoning

A retrospective review was conducted of 1,230 human poison exposures in which syrup of ipecac was administered to determine the availability of this emetic. Ipecac was available in 41.1% of the homes, while 42.5% obtained it from the pharmacy. Eight and two tenths percent were referred to a health care facility, 2.9% obtained ipecac from a neighbor, 2.3% went to an emergency room prior to calling the poison center, and 3% obtained ipecac from other sources. A randomly selected sample of 150 of these 1,230 cases were contacted 6 months after their initial call to the poison center to determine any changes in the availability of syrup of ipecac in the home. Although almost 30% more homes had syrup of ipecac than previously, 22.2% of homes still did not have ipecac available, despite the previous poisoning experience. Greater effort should be made during follow-up to educate the public regarding ipecac and its use.     

Transposition procedures in strabismus

A transfer procedure is very useful in the treatment of strabismus. The most common use of this procedure is to augment an already planned resection or recession procedure so that it can be performed monocularly to reduce an accompanying hypertropia or hypotropia or to collapse the A or V pattern when horizontal surgery is being performed for estropia or exotropia. In transfer procedures, the resultant change of deviation and cosmetic improvement is good or excellent in almost all cases. Some special transfer procedures, such as the Harada-Ito or the Jensen operation, can have dramatic effects on both comfort and change of symptoms for the patient.     

Effects of neurotransmitters or drugs on the in vivo release of dopamine and its metabolites

The effects of neurotransmitters or drugs on the release of endogenous dopamine (DA) and extracellular levels of its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), were examined in vivo by intracerebral dialysis. A dialysis tube was implanted stereotaxically through bilateral caudate nuclei of rats and perfused with the Ringer solution. Amounts of DA, DOPAC and HVA in the perfusates were measured by high performance liquid chromatography (HPLC) with electrochemical detection. The basal level of DA was 2.76 +/- 0.64 pg/min, whereas the levels of DOPAC and HVA were 218.7 +/- 20.7 and 142.4 +/- 10.6 pg/min, respectively. Apomorphine (4 mg/kg, i.v.) reduced the efflux of DA and its metabolites. Haloperidol (0.4 mg/kg, i.v.) did not change DA release and produced only a minor increase of its metabolites. This increase of metabolites was inhibited by pargyline. Met-enkephalin (10(-4) M), substance P (10(-4) M) and acetylcholine chloride (10(-4) M) added to the perfusing medium increased the release of DA. Met-enkephalin also increased the release of DOPAC. gamma-Amino-n-butyric acid (GABA, 10(-4) M) reduced the release of DOPAC and HVA when added to the perfusing medium. Thyrotropin releasing hormone (TRH, 5 mg/kg, i.v.) increased the release of HVA. These findings indicated that different mechanisms mediated effects of neurotransmitters or drugs on the release and metabolism of DA in the rat striatum.