Human breast cancer in vivo: H-1 and P-31 MR spectroscopy at 1.5 T

To assess the potential of in vivo magnetic resonance (MR) spectroscopy for breast cancer, hydrogen-1 and phosphorus-31 MR spectra of five malignant human breast tumors were compared with those of unaffected breast tissue. The water-to-fat ratio was high in the tumors (average, 2.2) but low in the unaffected tissue (average, 0.3). The P-31 spectrum of normal breast tissue showed low levels of phosphomonoesters (PMEs), inorganic phosphate, phosphodiesters (PDEs), and ATP. In addition, an intense phosphocreatine (PCr) signal was observed in breast tissue of young women: The relative intensities of the PCr and ATP signals had a mean value of 1.9. The tumor spectrum showed elevated levels of PMEs, Pi, and PDEs, while no PCr was seen (PCr/ATP less than 0.2). In two breast cancers treated with radiation therapy, resulting in a decrease of tumor volume of more than 50%, a similar change in the tumor P-31 spectrum was observed: An intense PCr signal developed (PCr/ATP = 1.1). Control experiments indicated that the appearance of PCr after radiation therapy was the result of a radiation-induced metabolic change in the tumor itself.     

Evaluation of non-invasive techniques to assess vasoconstriction in healthy volunteers using methoxamine as a probe drug

Non-invasive methods for assessment of the vascular effects of antimigraine drugs were evaluated with respect to their utility, variability and sensitivity in a double-blind, placebo-controlled, three-period crossover study in six healthy volunteers using an intravenous vasoconstrictor, methoxamine, as a probe drug. Changes in the internal diameter of the brachial and radial arteries were measured using ultrasound which had low between-day and within-day coefficients of variation. Peak systolic velocity (PSV), time-averaged velocity (TAV), total flow, resistance (RI) and pulsatility indices (PI) were measured by Doppler from one arterial wave form. Whilst PSV and TAV increased with methoxamine, because of bradycardia, changes in PI and RI were difficult to interpret. An automatic oscillametric cuff, a mercury-in-silastic strain gauge method and the "Finapres", finger arterial blood pressure monitor were used to follow changes in systolic blood pressure (SBP). The strain gauge technique underestimated arm SBP compared to the oscillometric method but clearly showed drug-related increases whilst the Finapres did not reflect changes in blood pressure detected by the other methods.     

An outbreak of gastroenteritis due to a heat-labile enterotoxin-producing strain of Escherichia coli.

In April 1981, an outbreak of gastroenteritis, characterized by diarrhea and abdominal cramps, occurred in 282 of approximately 3,000 personnel at a large metropolitan hospital in San Antonio, Tex. There was a significant association between illness and eating at the hospital cafeteria (P = 0.0008), but no specific food could be incriminated. Stools or rectal swabs from 54 ill individuals produced almost pure cultures of Escherichia coli. Cultures from 51 of these subjects had identical antibiotic sensitivity patterns, and 38 had the same biotype. Isolates from 45 persons were tested for production of heat-stable and heat-labile enterotoxins, using the suckling mouse and Y-1 adrenal cell assays, respectively. Of 45 isolates, 41 produced heat-labile enterotoxins, while 0 of 45 produced heat-stabile enterotoxins. Two isolates were rough, and 34 of the remaining 43 were serotype O25:H-. Two strains were O25:H+. None of the 45 strains possessed hemagglutination patterns typical of colonization factor antigens I or II. Six of seven O25:H- heat-labile enterotoxin-positive strains selected at random were piliated as seen by electron microscopy but did not agglutinate with anti-colonization factor antigens I or II antisera.     

Sterilization of complete dentures with sodium hypochlorite

It is important to give the patient a denture that is clean and free from cross-contamination. This study was made to determine if Clorox could be used as a rapid, safe, and clinically effective way to sterilize complete dentures. The data obtained from this study indicate that a 5-minute immersion of dentures in undiluted Clorox accomplished sterilization against a variety of microorganisms, including a spore-forming bacteria and C. albicans.