Magnetic resonance imaging of penile metastases: A report on five cases

Five cases of penile metastases are presented. Axial and sagittal T1-weighted and T2-weighted scans were performed in all patients. In some, coronal images were also obtained. The penile metastases were most often seen as discrete masses in the corpora cavernosa or corpus spongiosum. An atypical pattern of diffuse infiltration is also illustrated. Limitations of cavernosography, ultrasound (US) and computed tomography (CT) are discussed. The magnetic resonance (MR) features of penile metastases and possible role MR may have in the management of these patients are described.     

Drip breast milk: its composition, collection and pasteurization

"Drip breast milk" is that milk which spontaneously drips from the contralateral breask during the suckling of an infant. Biochemically and immunologically, pooled drip milk resembled pooled mature expressed breast milk, although it has a lower fat concentration. About 15% of lactating women are capable of producing drip milk; volumes produced are up to 188 ml/donor/day. A milk bank is described which processes 1400 liters of drip milk/yr. Heat treatment of this milk with a semi-automated holder pasteurizer caused a 21% reduction in IgA concentration and a 36% reduction in lysozyme activity, as well as a decrease in the ability of the milk to inhibit the growth of E. coli. In comparison with boiling, pasteurization was as effective in reducing total bacterial content provided the milk initially contained fewer than 10(6) bacteria/ml.     

Intracellular elemental concentrations in resting and secreting rat parotid glands

Electron probe x-ray micro-analysis was used to study the elemental concentration changes that occur during pilocarpine-stimulated saliva secretion. Quantitative x-ray micro-analysis of elemental concentrations in intracellular compartments of rat parotid glands stimulated in vivo with pilocarpine showed that Na concentration was significantly increased, while K concentration was significantly reduced. The magnitude of these changes was consistent with values obtained in other tissues with the x-ray micro-analysis method, and in the same tissue with other experimental methods. Comparisons with results from studies utilizing dispersed acini suggest that acinar dispersion procedures may affect intracellular elemental concentrations. Total electrolyte concentrations in cytoplasm and secretory granules were estimated to increase on a dry-weight basis following pilocarpine stimulation. The former change is consistent with the notion of a transcellular route of salivary fluid flow, while the latter change may be important in the exocytosis of secretory granules.     

Proconvulsant effects of theophylline on hippocampal afterdischarges

We tested the effects of the adenosine antagonist, theophylline, on electrically induced afterdischarges in the hippocampus of rats. Theophylline did not significantly alter the threshold for afterdischarge initiation or the duration of the initial afterdischarge. However, theophylline greatly prolonged the duration of secondary afterdischarges, and permitted generalization to motor seizures. Because theophylline antagonizes adenosine, and the hippocampus is a region rich in adenosine binding sites, we interpret these results to mean that endogenous adenosine has little action on focal seizure initiation, but a strong action to suppress secondary seizures and to inhibit seizure generalization.     

Comparison of dorsal and ventral spinal root regeneration through semipermeable guidance channels.

Semipermeable guidance channels have been shown to support nerve regeneration in the peripheral nervous system (PNS) possibly through interactions with the wound healing environment. This study quantitatively assesses the ability of such channels to support regeneration in the PNS segment of the spinal roots across a 4 mm gap and compares the resultant dorsal and ventral root regeneration. Acrylic copolymer guidance channels with a molecular weight (Mw) cutoff of 50,000 Da were used in a transected rat spinal root model. Cohorts of 23 animals (11 ventral, 12 dorsal) were examined at four weeks; 6 animals (3 ventral, 3 dorsal) at ten weeks; and 10 animals (5 ventral, 5 dorsal) at twenty-four weeks post-implantation. Both the dorsal and ventral roots were able to regenerate across the gap within the semipermeable channel. At all time periods, the regenerated dorsal roots contained fewer myelinated axons than found in the contralateral control root and consisted of an abundance of collagenous tissue. In contrast, by ten weeks the regenerated ventral roots contained twice the contralateral control number of myelinated axons and were composed predominantly of large, myelinated axons. At twenty-four weeks the number of unmyelinated axons was also quantified, with the regenerated dorsal root containing only one-fifth of the control number and the regenerated ventral root containing more than four times the control. Due to the proximity of the dorsal root lesion to the axonal cell bodies, the dorsal root ganglion (DRG) neuronal cell loss was investigated at four weeks post-implantation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Fading of nipple-areolar reconstructions: the last hurdle in breast reconstruction?

Fading of nipple-areolar reconstructions is commonly reported, but there are few formal studies of this phenomenon. The purpose of this study was to determine whether deficiencies in nipple-areolar reconstruction and pigmentation were perceived by patients, their partners and independent observers, and whether a technique could be developed to measure nipple-areolar colour reliably. A total of 57 patients, 32 partners and four independent observers completed questionnaires about the appearance of the patients' breast reconstructions in general and specifically about their nipple-areolar reconstructions. Scores for the general attributes of the breast reconstruction were used as internal controls for the scores of the nipple-areolar reconstruction. A computer software package was developed to analyse colour in photographs of the reconstructions. Independent observers thought that nipple-areolar reconstruction improved the appearance of a breast reconstruction 81% of the time. Considerably fewer patients were happy with their nipple-areolar colour than were happy with the more general attributes of the breast reconstruction (P < 0.005). Colour analysis objectively demonstrated measurable mismatch between normal and reconstructed nipple-areolar skin, which was positively correlated with time since surgery due to fading of the nipple-areolar reconstruction. In our patients, the quality of nipple-areolar reconstruction, in particular its pigmentation, is seen as inferior to that of the rest of the breast reconstruction in the eyes of patients, their partners and independent observers. The poor colour match and fading of reconstructed nipple-areolar skin are phenomena that can be measured using colour analysis.     

Noncardiogenic pulmonary edema caused by decompression sickness: rapid resolution following hyperbaric therapy

Noncardiogenic pulmonary edema is a recognized but uncommon manifestation of type 2 decompression sickness. It typically occurs within 6 hours of a dive. Because the adult respiratory distress syndrome in this setting is believed to be due to microbubbles in the pulmonary vasculature, recompression in a hyperbaric chamber has been recommended as a form of therapy. A patient developed noncardiogenic pulmonary edema following a seawater dive to 75 feet. There was complete radiologic and clinical resolution within 5 hours of hyperbaric therapy.     

Personal protection measures against fire ant attacks.

BACKGROUND: Fire ant stings lead to significant morbidity and mortality each year. Virtually no information exists in the scientific literature about the effectiveness of personal protection measures against these ants. OBJECTIVES: To quantify the level of protection from ant stings by socks and cotton tights and to evaluate the efficacy of repellents and other chemicals in preventing stings. METHODS: Commercially obtained infant socks were fitted on a plastic doll's foot, which was touched to fire ant mounds in a series of controlled experiments. Socks and cotton tights were stretched over a human finger and placed in a fire ant mound to test the ability of ants to sting through fabric. Assays were developed to screen chemical substances for their ability to stop or prevent fire ant stings. RESULTS: Socks of any type reduced the number of fire ants that reached the skin and delayed the time required for ants to reach the skin above the sock level. Fire ants were unable to sting through all socks tested. Ants successfully stung both paper towels and human skin, regardless of chemical substance or repellent applied to them. CONCLUSIONS: Socks provide some degree of protection from fire ant stings; therefore, children living in fire ant-infested areas should wear them. Fire ants appear unable to sting through many commercially available socks. Cotton tights may be useful in protecting the lower extremities of children. Fire ants are not deterred from stinging by a wide variety of insect repellents and chemical substances.     

Receiver operator characteristic (ROC) curves and non-normal data: an empirical study

This paper evaluates the performance of several diagnostic kits for assessing levels of serum prostatic acid phosphatase on patients at different stages of cancer of the prostate. Each patient was studied with several kits. We compare results obtained for receiver operator characteristic (ROC) curve methodology with data assumed to follow a normal distribution, with log-transformed data assumed to follow a normal distribution, and when neither of these assumptions holds. There were important differences between the results of the different approaches. For these data, the normal distribution assumption should be used with extreme caution. The log-transformed based results compared favourably with the non-parametric, but unconsidered application of the method should be avoided.     

CT appearances of relapse of lymphoma in the lung

The patterns of pulmonary relapse were studied in 15 patients with Hodgkin's disease and one patient with Non-Hodgkin's lymphoma. All the patients with Hodgkin's disease had mediastinal lymphadenopathy at initial diagnosis. For those patients with no prior episodes of relapse the mean time to pulmonary involvement was 2 years 11 months compared to over 8 years for those who first relapsed elsewhere. Thirteen patients are still alive; five have been followed up for more than 2 years. Pulmonary involvement consisted of: 1. nodules, either central (12 patients) or peripheral (10 patients), often with connection to the pleura or mediastinum, and sometimes with cavitation; 2. consolidation with or without cavitation (four patients); 3. mediastinal extension into the lung parenchyma (three patients). In seven patients there was evidence of newly enlarged mediastinal nodes. Pleural effusions or masses were seen in six patients and pericardial involvement in one. The chest wall was involved in five. A combination of three or more of these signs were present in 11 patients. The pattern of involvement seen in the patient with Non-Hodgkin's lymphoma was indistinguishable from that seen in Hodgkin's disease. This study has demonstrated a variety of CT appearances useful in establishing or suggesting the diagnosis of pulmonary relapse. Enlarged mediastinal nodes were not a prerequisite but had been present in all patients at some stage in the course of the disease.