Correlates of breast-feeding in a low-income population of whites, blacks, and southeast Asians

Infant feeding was examined in 492 children in a population-based survey conducted in a low-income, urban county of St Paul, Minn. Of 41 Southeast Asian infants who were foreign born, 93% (38) had been breast-fed compared with 10% (12) of Southeast Asian infants born in the United States (n = 116). Among non-Southeast Asian infants, 73% (173) of whites (n = 237), 63% (27) of blacks (n = 43) and 65% (36) of other ethnic groups (n = 55) had been breast-fed. Among the non-Southeast Asian infants, the initiation of breast-feeding was associated with higher parental education and with being married. Ethnic group, level of poverty, and participation in the Supplemental Food Program for Women, Infants, and Children during pregnancy did not appear to influence the initiation of breast-feeding. The findings indicate a higher incidence of breast-feeding than in previous surveys of low-income black and white women; however, this may reflect the higher educational level of the non-Southeast Asian study population. In contrast, the sharp decline in the incidence of breast-feeding among Southeast Asian infants who were born in the United States compared with those who were foreign born indicates the need for public health approaches to strengthen traditional breast-feeding practices.

Comparison of fat agglutination slide test and latex test for C-reactive protein

A slide test for detecting elevated levels of serum CRP using Intralipid and calcium chloride is described. The test obtains results similar to those of a latex agglutination test with which it was compared. The test is extremely quick and easy to perform. It may be of use as a cheap alternative to latex agglutination as a rapid screening or bedside test for elevated levels of CRP.

Nuclear magnetic resonance pulse sequence and discrimination of high- and low-fat tissues

Signal size compared to independently measured T1 is described for various pulse sequences on the Aberdeen Mk II nuclear magnetic resonance imager. The ability of these sequences to discriminate between certain tissue types, and in particular between adipose tissue and muscle, is discussed. Inversion recovery, with a t interval of 200 ms, gives the best discrimination for this purpose, with a contrast ratio of 6 between fat and muscle. Other image types, and especially T1, give better contrast for low-lipid soft tissue such as liver and spleen.

Local hyperthermia induced by focussed and overlapping ultrasonic fields--an in vivo demonstration

Axial temperature distributions were measured in living and post mortem porcine tissues during sonication with plane, focussed and overlapping ultrasonic fields. With the focussed field it was always possible to induce the temperature maxima at depths up to 50 mm, although the actual temperatures achieved varied from animal to animal. The plane 0.75 MHz transducer produced a maximum temperature close to the skin surface. With 7 overlapping plane fields a relatively uniform temperature distribution was produced in a large tissue volume. The blood perfusion in tissue has a significant effect not only on the magnitude of the temperature increase, but also on the temperature distribution.

The construction and assessment of lenses for local treatment of malignant tumours by ultrasound

A simple method to build ultrasound lenses from araldite has been developed. The focussing properties of these lenses as a function of sonic frequency and lens diameter were studied using a computer model. The optimum frequency and diameter of these lens were found to be around 1 MHz and between 40 and 60 mm respectively, for deep tissue heating. The stability of the power output as well as the temperature distributions produced in vitro and in vivo have also been studied. It appears to be possible to produce larger temperature elevations near the acoustical focus than near the skin surface in vivo. Therefore the lenses seem to be suitable for local cancer treatment.