Use of radionuclide scanning to estimate size of spleen in vivo.

Splenic ultrasound was performed and spleen scans obtained by a rectilinear scanner after injection of In-113m-labelled heat damaged red cells on 14 patients with various haematological disorders. Correlation was assessed between the measured volume of the operatively removed spleens, their volumes as calculated from the ultrasound data, and their preoperative dimensions of length, circumference, and area on the scans. The relation of scan to volume was best defined by an equation V = 9.88A - 534, where V = volume of spleen (cm3) and A = area (cm2) on posterior scan. The mean percentage difference between calculated and actual spleen volume was 0.2 (SD 6.7)%. Average spleen density was established as 1.04 g/cm3. The formula was shown to be reliable in the range of splenic area c 73-450 cm2--that is, volume c 185-4000 cm3. This range includes the average normal sized spleens and the splenomegalies that are most often found in clinical practice. The formula is not valid when the spleen is smaller than normal. As the method depends on measurement of the spleen image shown by scintigraphs, it cannot be used when there is functional asplenia.     

Disseminated talc granulomatosis. An unusual finding in a patient with acquired immunodeficiency syndrome and fatal cytomegalovirus infection

The association of disseminated magnesium silicate talc granulomatosis and acquired immunodeficiency syndrome is reported in a male homosexual who used intravenous drugs and who died of overwhelming cytomegalovirus (CMV) infection. Autopsy findings included widespread deposition of talc crystals in the lungs, liver, lymph nodes, bone marrow, and spleen. Typical CMV inclusions were seen in the lungs, kidneys, adrenal glands, gastrointestinal tract, and right eye. There was no evidence of malignancy. Analysis of peripheral blood neutrophil function revealed impaired chemotaxis and chemokinesis, but opsonophagocytosis had remained normal. The CMV infection in the small bowel was extensive and resulted in severe destruction of the muscularis propria and neural plexi, leading to marked dilatation and persistent diarrhea. The terminal course was marked by intractable hypotension, pneumonitis, and malnutrition, which could be attributed respectively to CMV involvement of the adrenal glands, lungs, and small bowel. The etiology and possible role of systemic talc granulomatosis in the development of immunosuppressive illness is reported herein.     

Bone marrow examination for the diagnosis of mycobacterial and fungal infections in the acquired immunodeficiency syndrome.

In a series of 342 bone marrow examinations from 314 patients with human immunodeficiency virus infection, 70 examinations (20%) detected opportunistic mycobacterial or fungal infections. One hundred eleven of the 314 patients had such infections, and, hence, 63% (70/111) were detected by bone marrow examination. Special stains for microorganisms detected 16 (32%) of 50 Mycobacterium avium complex infections, 10 (22%) of 45 Mycobacterium tuberculosis infections, eight (73%) of 11 Histoplasma capsulatum infections, and five (83%) of six Cryptococcus neoformans infections. Bone marrow cultures detected 36 (72%) of the 50 M avium complex infections, 13 (29%) of the 45 M tuberculosis infections, and 63% of the fungal infections. Marrow examination revealed infection in only one of the 70 specimens (1%) collected to evaluate thrombocytopenia alone or hematologic malignancy, but in 69 (25%) of 274 with fever, neutropenia, anemia, or miscellaneous other indications for marrow examination. Granulomas were detected in 102 (30%) of the biopsy specimens, including 71 (64%) of those in cases with mycobacterial or fungal infection. The granulomas showed caseous necrosis in nine cases, all in patients with tuberculosis, and the 27 cases with tuberculosis-associated granulomas tended to show large, tightly cohesive granulomas. The presence of granulomas correlated with opportunistic infection in 82 (80%) of 102 cases. Without granulomas, special stains were positive in only eight (3%) of 240 specimens. These results suggest that (1) bone marrow granulomas are a common and valuable histologic clue to opportunistic infection; (2) without them, special stains may not be a cost-efficient way to diagnose such infection; and (3) bone marrow examination can be a useful method of diagnosing opportunistic mycobacterial and fungal infections in patients with fever, anemia or neutropenia, and underlying human immunodeficiency virus infection.     

Theophylline reversal of electroconvulsive therapy (ECT) seizure inhibition

Oral sustained-release theophylline 200-400 mg, given 10 hours prior to electroconvulsive therapy (ECT) increased ECT seizure length in each of eight male patients who had shown unacceptably short seizures. The increase was on average 13.9 (+/- 6.0, SD) sec (p = .00016 by t test; p = .0000034 by exact probability). The absence of unduly prolonged seizures was attributed to previously demonstrated high seizure thresholds and to relatively low concentrations of theophylline. No adverse effects from theophylline were seen.     

Evaluation of a summer prematriculation program for black and other nontraditional students.

This study evaluated the effectiveness of the Medical College of Georgia School of Medicine's Summer Prematriculation Program in facilitating participants' first-year achievement and retention from 1980 to 1989. The four-week curriculum included biochemistry, anatomy, immunology, learning skills, medical or anatomy terminology, and clinical forums. Of 101 black and 96 other nontraditional, at-risk students who had been invited to attend the program, the 115 attendees were compared with the 82 nonattendees on a variety of demographic and academic measures. For all measures examined, no statistically significant difference was found between the two groups. Several factors may have obscured the results. However, there were indications that the program had a favorable effect, including the evaluation by over 90% of the attendees that the program had contributed positively to their adjustment to medical school.     

Group behavioral treatment of retentive encopresis

Investigated the efficacy of behavioral group treatment for children with retentive encopresis who had previously failed medical management. Eighteen children between the ages of 4 and 11 years and their parents were seen in small treatment groups of 3 to 5 families over 6 sessions. The sessions focused on education about retentive encopresis, and the integration of behavioral parenting procedures with medical management. Parents and children were taught to deliver an enema clean-out, increase the children's dietary fiber, and appropriate toileting techniques. The results indicated that children significantly increased their fiber consumption by 40%, increased appropriate toileting by 116%, and decreased their soiling accidents by 83% pre- to posttreatment. Further, these treatment gains maintained or improved at the 6-month follow-up. The results are discussed in terms of cost-effective interventions and the interface between psychology and medicine in pediatric psychology.     

Indices of oxidative stress in hamster lung following exposure to cobalt(II) ions: in vivo and in vitro studies

Cobalt, a metal with numerous industrial applications, has been associated with lung disease, an extreme form of which is an interstitial fibrosis. The biochemical mechanisms underlying this toxicity are not understood. In vitro studies have suggested that cobalt(II) ions are able to generate reactive oxidant species (possibly hydroxyl radical) in a reaction with hydrogen peroxide, and we have hypothesized that the occurrence of such an event in lung tissue, and the subsequent development of oxidative damage, may contribute to this pulmonary toxicity. The intratracheal instillation of CoCl2 into hamster lungs resulted after 3 h in decreased levels of reduced glutathione and increases in levels of oxidized glutathione and in the activity of the pentose phosphate pathway. These changes, which are compatible with the generation of oxidative stress, were reversed by 48 h at low Co2+ doses (1.0 to 1,000 micrograms/kg). Irreversible changes at higher doses coincided with the onset of pulmonary edema. Incubation of lung slices with CoCl2 (0.1 to 10 mM) resulted in time- and Co2+ concentration-dependent increases in levels of oxidized glutathione and protein-mixed disulfides and a decrease in reduced glutathione. A concentration-dependent stimulation of the pentose phosphate pathway was also observed. These changes preceded the detection of overt cell toxicity, as assessed by various biochemical parameters. These data indicate that thiol oxidation constitutes an early event in the pulmonary toxicity of cobalt(II) ions and are compatible with the hypothesis that the generation of oxidative stress may be of significance to the toxic process.     

Immunology of HIV infection

The goal of finding an effective vaccine against the human immunodeficiency virus (HIV) is hampered by our uncertainty of the mechanism(s) responsible for the pathogenesis as well as the lack of knowledge of protective mechanisms. The effects of HIV on the immune system are myriad and thus the truly significant manifestations of the pathology are difficult to dissociate from those more peripheral. In this article we will initially characterize the natural history of HIV infection which shows a chronic and perhaps inexorable course. The second part will deal with the immune response mounted against this assault and the final section is a discussion of the possible unfavorable consequences of the immune response that humans muster against this agent.     

The honeybee syndrome - implications of the teratogenicity of mannose in rat-embryo culture

Lethal effects of D-mannose in the honeybee have been recognized for more than a half a century. We observed another toxic effect of D- mannose during culture of rat embryos from the early head-fold stage to the 26-to-29-somite stage (Days 9-1/2 through 11-1 of gestation). The addition to culture mediums of 1.5 mg of D-mannose per milliliter caused growth retardation and faulty neural-tube closure in approximately two thirds of the embryos. Mannose effects occurred during the first 24 hours of culture and were attended by modes inhibition of the glycolysis that constitutes the principal energy pathway at this stage of development. Adding more glucose to preserve glycolytic flux or increasing atmospheric oxygen to promote oxidative metabolism offset the mannose teratogenesis. Our findings highlight the metabolic vulnerabilities that exist during early organogenesis, before oxidative flexibility is established. They may serve as a model to explain the teratogenicity of many other seemingly unrelated agents that could act by perturbing glycolysis at this vulnerable stage.