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10Be is an important isotope for accelerator mass spectrometry (AMS) because of the demand for cosmogenic radionuclide dating methods in the earth science and paleo-sciences community. At the iThemba Laboratory for Accelerator Based Science (iThemba LABS) we implemented full suppression of the interfering isobar 10B using a silicon nitride foil-stack, utilizing the 2+ charge state for high efficiency. We demonstrate the performance of this newly established AMS system using standards and test samples. We further present the results of an inter-comparison between iThemba LABS and the Center for Accelerator Mass Spectrometry/Lawrence Livermore National Laboratory, on AMS samples prepared from purified quartz at the University of Vermont. The results for 10Be from the laboratories are in close agreement, fully consistent with cross-calibration between them. AMS results for 26Al are in similarly good agreement, demonstrating the performance and accuracy of iThemba LABS for the most commonly measured in situ produced cosmogenic nuclides.

Soluble transferrin receptor (sTfR), previously shown to be a sensitive indicator of tissue iron deficiency, was used to assess iron status of 104 Zairean women (69 lactating, 19 pregnant, and 16 nonpregnant, nonlactating women). Thirteen iron-sufficient female laboratory employees were also studied. Mean sTfR concentrations were higher in pregnant women (9.90 mg/L) than in lactating women (8.55 mg/L), nonlactating women (7.74 mg/L), and laboratory employees (5.11 mg/L) (P0.005). Mean serum ferritin and transferrin saturation were lower in pregnant than nonpregnant women. sTfR negatively correlated with hemoglobin (P0.05) and transferrin saturation (P0.05), and nonsignificantly with ferritin and transferrin. With 7.26 mg sTfR/L (the upper limit of laboratory employees) as the cutoff value, sTfR identified 67% of women with tissue iron deficiency compared with 11.5-57% for transferrin saturation, hemoglobin, or ferritin. Despite the moderate sensitivity (68.5%), 90% of women with sTfR7.26 mg/L also had another index below normal and 54% had serum ferritinor = 50 micrograms/L.

Acute phase proteins (APP) are plasma proteins secreted by the liver following inflammation. APP reference levels are unknown for healthy female Zaireans. The purpose of this study was to determine: (a) the reference levels of alpha 1-acid glycoprotein (AGP), C-reactive protein (CRP), ceruloplasmin (Cp), and haptoglobin (Hp) in healthy Zairean adult women, and (b) whether the levels are different between lactating (Group I), pregnant (Group II) and non-pregnant/non-lactating women (Group III). APP were measured by radial immunodiffusion in 180, 212 and 27 women of Groups I, II, and III respectively (age range 15-45 years). The ranges for different APP were wider than for Western adults or those obtained in plasma from normal laboratory personnel. The means and medians of AGP were lower in pregnant that non-pregnant women, and those of CRP and Cp were higher. There were no differences in mean Hp levels between the three groups. In non-pregnant women, the mean levels and 95% confidence limits of CRP, Cp and Hp were within published ranges for healthy Western adults, while those of AGP were higher. In pregnant women only AGP and Hp were within published ranges. We conclude that, at least in non-pregnant women, the same cut-off points of CRP, Cp and Hp used for Western adults may also be used in the assessment of inflammation in Zairean women.

We studied the usefulness of serum ferritin for the assessment of iron deficiency (ID) or ID anaemia (IDA) of 186 lactating and 27 non-lactating Zairean women (15-45 years old). Haemoglobin (Hb), serum iron (SI), total iron binding capacity (TIBC), and transferrin saturation (TS) were also measured. Participants were recruited in rural Bas-Zaire State in the summers of 1986 and 1989. Serum ferritin ranged from 10 to 360 micrograms l-1 (median 62 micrograms l-1) in lactating women and from 14.2 to 120 micrograms l-1 (median 40 micrograms l-1) in non-lactating women. While mean levels of serum ferritin and TS were within the normal range in both groups of women, those of Hb were below normal (12 g dl-1), partly due to inflammation. The prevalence of anaemia was 66% in lactating women and 70% in non-lactating women, and did not change with time. It was higher in women with inflammation than in those without inflammation. Although ID (ferritin12 micrograms l-1) was almost absent, after raising the cut-off point of ferritin to 50 micrograms l-1 in women with inflammation, it was present in 28.8% of lactating women and 52% of non-lactating women. While the prevalence of ID assessed by serum ferritin was significantly higher in lactating women studied in 1989 (40.5%) than in those studied in 1986 (13.5%), it was similar in both groups of non-lactating women. ID defined by TS16% was present in 41% of lactating women and 21% of non-lactating women. In the presence as well as absence of inflammation, the use of TS identified a higher percentage of lactating women with either ID or IDA than did the use of serum ferritin. We conclude that, in the studied population, unless inflammation is taken into consideration, serum ferritin has a limited value in the diagnosis of ID.This cross-sectional study involved 213 healthy Zairian women, 15-45 years old, 186 lactating and 27 nonpregnant, nonlactating women and studied the usefulness of serum ferritin levels for the assessment of iron deficiency (ID) or ID anaemia (IDA). Hemoglobin (Hb), serum iron (SI), total iron binding capacity (TIBC), and transferrin saturation (TS) were also measured. The median parity of lactating women was three, and that of nonlactating women was two. They were recruited at the Nsundi Lutete Hospital (Bas-Zaire State) during August and September of 1986 and 1989. Serum ferritin ranged from 10 to 360 mcg 1-1 (median 62 mcg 1-1) in lactating women and from 14.2 to 120 mcg 1-l (median 40 mcg 1-l) in nonlactating women. While mean levels of serum ferritin and TS were within the normal range in both groups of women, those of Hb were below normal ( 12 g dl-1), partly owing to inflammation. The prevalence of anemia was 66% in lactating women and 70% in nonlactating women, and did not change with time. It was higher in women with inflammation than in those without inflammation. Although ID (ferritin 12 mcg 1-1 ) was almost absent, after raising the cut-off point of ferritin to 50 mcg 1-1 in women with inflammation, it was present in 28.8% of lactating women and 52% of nonlactating women. While the prevalence of ID assessed by serum ferritin was significantly higher in lactating women studied in 1989 (40.5%) than in those studied in 1986 (13.5%), it was similar in both groups of nonlactating women. ID defined by TS 16% was present in 41% of lactating women and 21% of nonlactating women. In the presence as well as absence of inflammation, the use of TS identified a higher percentage of lactating women with either ID or IDA than did the use of serum ferritin. In the studied population, unless inflammation is taken into consideration, serum ferritin has a limited value in the diagnosis of ID.

A population of 183 Zairean infants and young children (0.5 to 48 months old) who lived in rural Bas-Zaire has been examined in regard to hemoglobin (Hb), hematocrit (Hct) and mean corpuscular hemoglobin concentration (MCHC). The mean Hb was 9.03 g/dL, Hct 28.4%, and MCHC 30.7 micrograms/dL. These means are below normal by WHO and/or American Academy of Pediatrics criteria. Although there was no significant sex difference in the mean hematoglobin measurements, boys more than 24 months old had a higher mean Hb (9.98 g/dL) than girls (8.59d g/L) of the same age. Approximately 80%, 76% and 56% of children had Hb11 g/dL, Hct34% and MCHC32 micrograms/dL respectively. The highest prevalence of anemia was between the age of 12 and 18 months. Severe anemia (Hb8 g/dL) was observed in 30.65% of the study population (26.6% boys and 34.8% girls). Approximately one third of children had very low Hct levels (or = 25%). Based on MCHC, iron deficiency was likely responsible of the anemia in 61% of the children. Both Hb (p0.05) and Hct positively correlated with the mother's level of education. Because of the many detrimental effects of iron deficiency in infants and young children on immunity, psychomotor, behaviour and mental development routine assessment of iron status and correction of iron deficiency should become a part of the Surveillance Programme in this population.