99mTc internal contaminations measurements among nuclear medicine medical personnel during ventilation - perfusion SPECT lung scans

This paper presents results of measurements of ^99mTc activity concentration in air and nuclear medical personnel blood during ventilation-perfusion SPECT lung scans. ^99mTc activity measurements were conducted at the Nuclear Medicine Department, John Paul II Hospital, Krakow. Technicians and nurses who perform examinations were equipped with personal aspirators enabling air sampling to determine the radiation exposure at their workplaces. Measurements allowed to evaluate the concentration of ^99mTc in 14 air samples and it ranged from 7800 ± 600 to 10,000 ± 1000 Bq m^-3 for air samples collected by technicians and from 390 ± 30 to 600 ± 40 Bq m^-3 for air samples collected by nurses. In addition ^99mTc concentrations in blood of medical personnel were determined in 24 samples. For technicians the maximum ^99mTc blood concentration levels reached 920 ± 70 Bq L^-1 and 1300 ± 100 Bq L^-1. In the case of nurses, the maximum estimated activity concentrations were about ten times lower, namely 71 ± 7 Bq L^-1 and 39 ± 3 Bq L^-1. Although the intakes appear to be relatively high, the resulting annual effective doses are about 34 µSv for technicians and only 2 µSv for nurses.

Exploring racial differences in IgE-mediated food allergy in the WHEALS birth cohort

BACKGROUND

Suspected food allergies are the cause of more than 200,000 visits to the emergency department annually. Racial differences in the prevalence of food allergy have also been reported, but the evidence is less conclusive. Researchers continue to struggle with the identification of food allergy for epidemiologic studies.

OBJECTIVE

To explore racial differences in IgE-mediated food allergy (IgE-FA) in a birth cohort.

METHODS

We used a panel of board-certified allergists to systematically identify IgE-FA to egg, milk, or peanut in a multiethnic birth cohort in which patient medical history, patient symptoms, and clinical data were available through 36 months of age.

RESULTS

Of the 590 infants analyzed, 52.9% were male and 65.8% African American. Sensitization (serum specific IgE >0.35 IU/mL) to the food allergens was significantly higher for African American children compared with non-African American children as has been previously reported. No statistically significant racial/ethnic differences in IgE-FA were observed; however, a higher proportion of African American children were designated as having peanut allergy, and the percentage of African American children with an IgE level greater than 95% predictive decision points for peanut was 1.7% vs 0.5% for non-African American children. With the use of logistic regression, race/ethnicity was not significantly associated with IgE-FA (adjusted odds ratio, 1.12; 95% confidence interval, 0.58-2.17; P = .75) but was associated with sensitization to more than 1 of the food allergens (adjusted odds ratio, 1.80; 95% confidence interval, 1.22-2.65; P = .003).

CONCLUSION

We did not observe an elevated risk of IgE-FA for African American children, although established differences in sensitization were observed. Racial/ethnic differences in sensitization must be taken into consideration when investigating disparities in asthma and allergy.

Transforming growth factor beta (TGFβ1) in breast milk and indicators of infant atopy in a birth cohort

BACKGROUND

The infant gut's ability to suppress immunologic reactions to food proteins could be influenced by levels of TGFβ in breast milk. We hypothesized that lower levels of TGFβ(1) in the breast milk (BM) of mothers in the WHEALS birth cohort are associated with atopy at infant age 2-3 yrs.

METHODS

We used data collected during infancy in addition to the results of skin prick tests (SPT+) and measures of specific IgE >0.35 IU/ml (spIgE) to milk, egg, and peanut at infant age 2-3 years. Infants were classified as food allergic (FA) based on parental report of infant symptoms/diagnoses and information from clinical assessments.

RESULTS

Data for 304 cohort members were analyzed. Among non-black infants, BM-TGFβ(1) was lower for those classified as FA (vs. no FA) and those SPT+ (vs., SPT-), geometric mean = 1100 pg/ml vs. 1417pg/ml, p = 0.081; and 1100 pg/ml vs. 1415pg/ml, p = 0.064, respectively. Among infants of non-atopic mothers, BM-TGFβ(1) was lower for those with elevated (vs. not elevated) sIgE, geometric mean = 1347 pg/ml vs. 1651 pg/ml, p = 0.047. Using logistic regression, adjusted odds ratios describing the association of BM-TGFβ1 to the presence of atopic indicators in the infant were in the hypothesized direction only for non-black infants of non-atopic mothers: aORs for FA, sIgE and SPT+ were 0.08, 0.34, and 0.26 respectively; p = 0.091, 0.13, and 0.23.

CONCLUSION

Immune benefit of BM-TGFβ(1) could inform prevention strategies. Evidence of an association appears greatly influenced by infant race and maternal atopy. More research can determine if these relationships represent a modifiable risk factor for the development of food allergy in certain subgroups.

Radiochemical separation of no-carrier-added 177Lu as produced via the 176Yb(n,gamma)177Yb-->177Lu process

The 176Yb(n,gamma)177Yb-beta(-)-->177Lu process was investigated to provide no-carrier-added (nca) 177Lu. The radiochemical separation of the 177Lu from the macro-amounts of the ytterbium target based on the cementation process, i.e. the selective extraction of Yb by Na(Hg) amalgam from Cl-/CH3COO- electrolytes, followed by a final cation exchange purification. The cementation separation process provides a decontamination factor of Yb(III) of 10(4), the cation exchange purification adding a decontamination factor of > 10(2). The nca 177Lu is available in radiochemically pure form despite the chemical similarity of the lanthanides with 75 +/- 5% overall separation yield within 4-5 h. It can be used to synthesise nca 177Lu labelled radiotherapeuticals.