Cerebral ischemia: magnetic resonance angiography and transcranial Doppler evaluation

We examined 21 patients with ischemic cerebrovascular disease using magnetic resonance angiography and transcranial Doppler. In 17 patients (81%), the results obtained by the two methods were concordant. In our opinion, the associated use of transcranial Doppler and magnetic resonance angiography provides an accurate diagnostic evaluation of ischemic stroke patients, not only allowing the site of possible steno-occlusive disease of large and medium cerebral vessels to be identified, but also offering the possibility of obtaining dynamic information concerning the direction of blood flow in the presence of compensatory circulations at the level of Willis' circle.

[Malignant tumors or the small intestine. Review of the literature and report of a clinical case]

The authors present one case of patients with adenocarcinoma of the small bowel. Primary malignant tumors of the small intestine are uncommon neoplasms accounting for 1-2 per cent of all gastrointestinal malignancies. Patients are usually seen late in the course of their illness when curative therapy is unlikely. The rarity of these neoplasms explains in part why the early signs and symptoms frequently go unrecognized and is undoubtedly a major factor contributing to their poor prognosis. Despite a fourfold greater length and a nearly tenfold greater mucosal surface area, the incidence of adenocarcinoma of the small intestine is about a fortieth that of the colon. This relative immunity of the small bowel to the development of the malignant tumors is unexplainable. Several theories have been suggested and include the following: a) the rapid transit time of the small intestine may reduce its exposure to dietary carcinogens; b) the relative sterility of the small intestine compared with the colon may lessen the formation of carcinogenic substances by the action of bacteria on components of bile or other substances within the intestinal lumen; c) certain mucosal enzymes such as benzopyrene hydroxylase that detoxify potential carcinogens are present in higher concentrations in the small intestine than in the colon; d) immunoglobulin A which is found in high concentrations in the small bowel, may protect it against carcinogenic viruses. Interestingly, patients deficient in IgA and those receiving immunosuppressive therapy have been found to have a higher incidence of small intestinal cancer. Adenocarcinoma is the most common primary malignant small bowel neoplasm.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolated diffusing capacity reduction in systemic sclerosis

OBJECTIVE

To determine the long-term outcome of patients with systemic sclerosis (SSc) and an isolated reduction in the diffusing capacity for carbon monoxide (DLCO) at the time of initial evaluation.

METHODS

Patients with an isolated reduction in DLCO (i.e., normal forced vital capacity [FVC] and normal ratio of the forced expiratory volume in one second [FEV1] to the FVC) on initial evaluation were identified from among 815 patients with SSc who were carefully followed up throughout their illness. We requested that patients have repeat pulmonary function testing (PFT), and the outcomes of these tests, as well as cardiopulmonary and survival outcomes, were determined.

RESULTS

An isolated reduction in DLCO, with a normal FVC was detected in 152 (19%) of the 815 patients. A subset of those with an isolated reduction in DLCO (11%) developed isolated pulmonary hypertension and had severely reduced survival rates. Pulmonary hypertension was strongly associated with an initial DLCO of less than 55% of predicted normal and a FVC (% predicted)/DLCO (% predicted) ratio of greater than 1.4. Among all patients in whom this ratio was greater than 1.4, 22% developed isolated pulmonary hypertension, compared with only 2% of those whose ratio was less than 1.4 (P less than 0.01). Of the 152 patients with isolated DLCO reduction, 73 (48%) underwent PFTs a mean of 5.4 years (range 2.0-13.2) after the initial PFT. Only 6 (8%) of these 73 patients ever had serious pulmonary disease: 5 had isolated pulmonary hypertension, and 1 had severe pulmonary fibrosis. Half of the patients with a low initial DLCO demonstrated a significant improvement (greater than 20%) at followup testing that could not be explained by the demographic, clinical, or laboratory findings at the first visit.

CONCLUSION

Isolated reduction in DLCO is a frequent abnormality in SSc. Overall, it is associated with a good prognosis for survival and for pulmonary morbidity. A small subset of patients (11%) who have a very low DLCO (less than 55% of predicted) have developed isolated pulmonary hypertension, all of whom had limited scleroderma.

[Clinico-diagnostic criteria of hypochondriac syndromes]

The aim of this study was to examine the vast field of hypochondriac symptoms and to put forward diagnostic criteria following the analysis of recent studies on this topic. The "descriptions" based on DSM III trace a partial and selective picture of hypochondriac disorders which is only applicable to a small group of patients in which "somatic complaints" are emphasised in comparison to other less evident psychological variables. The symptom therefore becomes a sign of a pathology which is not defined according to the same complex of symptoms from which it arose. There is in fact no nosological model of hypochondria: we are only likely to meet a "potential hypochondriac" whose pathological expression is limited to part of the population.

A double blind randomized pilot trial of naloxone in the treatment of acute ischemic stroke

Attention has focused on naloxone, an opiate receptor antagonist, because of its potential benefit in reversing neurological damage after acute cerebral ischemia. To evaluate the safety and possible efficacy of high-dose naloxone in ischemic stroke patients we planned a double blind pilot study. Between January 1989 and May 1990 24 patients were randomly assigned to the naloxone or placebo group according to age and neurological deficit. Naloxone was given in a loading dose of 5 mg/kg over 10 minutes followed by a 24-hour infusion at the rate of 3.5 mg/kg/h. 10 patients experienced minor side effects but none of them had to discontinue the treatment. 9 patients improved: 6 in the naloxone group and 3 in the placebo group, but no significant difference was found using the non parametric Mann-Whitney test. Our study suggests that naloxone is safe at the dose used, but the results do not support the planning of similar trials on a larger scale.

Pregnancy in women with systemic sclerosis

We assessed fetal morbidity and mortality in women with systemic sclerosis (SSc). Women with a history of SSc and a concomitant pregnancy completed a detailed questionnaire about the pregnancy. These 48 subjects were age-matched and race-matched to 2 other groups of women (a rheumatoid arthritis group and a control group from the same neighborhood), all of whom had been pregnant at least once. There were no differences in the frequencies of miscarriage or perinatal death in the SSc group compared with the 2 control groups. Preterm births occurred slightly more frequently in both SSc patients and rheumatoid arthritis patients compared with the neighborhood control subjects. There were significantly more small full-term infants born to women with SSc. Interestingly, the increase in preterm births and small full-term babies occurred with equal frequency prior to and after the onset of disease. Although close monitoring for premature birth and intrauterine growth retardation is necessary, we conclude that an uneventful, healthy pregnancy is possible for women with SSc. Those with early, rapidly progressive, diffuse skin thickening should avoid becoming pregnant since, intrinsically, they are at higher risk of developing renal crisis.

Energy transfer by an exchange mechanism in fluid solutions. A generalized treatment

Energy transfer in solution by an exchange mechanism has been analysed. The diffusion equation with an added sink term describing the energy transfer process was solved for steady-state conditions using the radiation boundary condition. The transfer rate constant so obtained takes into account the possibility that the reaction does not occur during an encounter. In the limit the equations contain the cases of totally absorbing and totally reflecting barriers. The short range effects were analysed and their influence was introduced under new boundary conditions.