Sowing date, transplanting, plant density and nitrogen fertilization affect indigo production from Isatis species in a Mediterranean region of Spain

The increasing interest in natural products from a renewable source has encouraged growers to reintroduce indigo-producing crops into the European agriculture. We studied agronomic conditions (sowing date, plant density, nitrogen fertilization, irrigation rate, seedling transplanting) influencing production of the blue pigment indigo, from Isatis tinctoria and I. indigotica crops in a Mediterranean region of Spain (Valencia). I. tinctoria was more suitable for cultivation in our climate conditions than I. indigotica. Indigo yield from Spanish I. tinctoria trials was greater than in Northern and Central Europe. Furthermore, indigo production was maintained when water and nitrogen supplies were significantly restricted, showing that I. tinctoria is not a high-demanding crop. © 2005 Elsevier B.V. All rights reserved

Commercial sex and the spread of HIV in four cities in sub-Saharan Africa.

OBJECTIVE: To examine whether commercial sex transactions were more common and/or transmission between sex workers and clients more efficient in two African cities with high HIV prevalence (Kisumu, Kenya and Ndola, Zambia) compared with two with relatively low HIV prevalence (Cotonou, Benin and Yaoundé, Cameroon). METHODS: Data on sexual behaviour, HIV and sexually transmitted infections were collected from representative samples of around 300 female sex workers in each city. Sexual behaviour data from a population-based study of around 1000 men aged 15-49 in each city were used to estimate the extent of contact with sex workers. RESULTS: The number of sex workers per 1000 males was highest in Kisumu and Ndola, but other estimates of the extent or characteristics of sex work contact showed no consistent differences between high or low prevalence cities. HIV prevalence among sex workers was 75% in Kisumu, 69% in Ndola, 55% in Cotonou and 34% in Yaoundé. The prevalence of genital ulceration and trichomoniasis was higher among sex workers in Kisumu and Ndola but no clear pattern was seen for the other sexually transmitted infections. Around 70% of sex workers in Cotonou reported use of a condom with the last client, markedly higher than in the other cities. CONCLUSIONS: Although sex work is likely to have played an important role in the spread of HIV in all four cities, differences in present patterns of sex work do not appear to explain the differential spread of HIV. However, high levels of condom use among sex workers may have slowed the spread from sex workers to the general population in Cotonou, highlighting the importance of interventions among sex workers and their clients

Educational level is associated with condom use within non-spousal partnerships in four cities of sub-Saharan Africa

Not the final published versionBACKGROUND: Rates of condom use in sub-Saharan Africa have remained too low to curb HIV/sexually transmitted disease (STD) epidemics. A better understanding of the main determinants of condom use would aid promotion. METHODS: Cross-sectional population surveys were conducted in four cities in sub-Saharan Africa: Yaoundé, Cameroon; Cotonou, Benin; Ndola, Zambia; and Kisumu, Kenya. In each city, the aim was to interview a random sample of 1000 men and 1000 women aged 15--49 years, including questions on characteristics of non-spousal partnerships in the past 12 months. RESULTS: Data on condom use were available for 4624 non-spousal partnerships. In the four cities, the proportion of partnerships in which condoms were used always or most of the time ranged from 23.8 to 33.5% when reported by men and from 10.7 to 25.9% when reported by women. Based on the reports from men, condom use was associated with higher educational level of the male partner in Yaoundé [adjusted odds ratio (aOR) = 1.76] and Ndola (aOR = 2.94) and with higher educational level of the female partner in Cotonou (aOR = 2.36) and Kisumu (aOR = 2.76). Based on the reports from women, condom use was associated with higher educational level of the female partner in Kisumu (aOR = 2.60) and Ndola (aOR = 4.50) and with higher educational level of the male partner in Yaoundé (aOR = 3.32). Associations with other determinants varied across cities and for men and women. CONCLUSIONS: Education was found to be a key determinant of condom use in all four cities. This suggests that educational level increases response to condom promotion and highlights the need for special efforts to reach men and women with low educational attainment

Multicentre study on factors determining differences in rate of spread of HIV in sub-Saharan Africa: methods and prevalence of HIV infection

Not the final published versionOBJECTIVE: The objective of this study was to explore whether the differences in rate of spread of HIV in different regions in sub-Saharan Africa could be explained by differences in sexual behaviour and/or factors influencing the probability of HIV transmission during sexual intercourse. METHODS: A cross-sectional, population-based study was conducted in two cities with a high HIV prevalence (Kisumu in Kenya and Ndola in Zambia) and two cities with a relatively low HIV prevalence (Cotonou in Benin and Yaoundé in Cameroon). In each of these cities, approximately 1000 men and 1000 women, aged 15-49 years, were randomly selected from the general population. Consenting men and women were interviewed and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection and trichomoniasis (the latter for women only). In addition, a survey was conducted on a random sample of 300 sex workers in each city. The research instruments, including the questionnaires and the laboratory procedures, were standardized to permit comparison of results. RESULTS: The numbers of men interviewed were 1021 in Cotonou, 973 in Yaoundé, 829 in Kisumu, and 720 in Ndola. The corresponding figures for women were 1095, 1116, 1060 and 1130. In Yaoundé, Kisumu and Ndola, the response rates for men were lower than for women due to failure to make contact with eligible men. The proportion of eligible women who were interviewed was 86% in Yaoundé, and 89% in Kisumu and Ndola. In Yaoundé, 76% of eligible men were interviewed, along with 82% in Kisumu and 75% in Ndola. The prevalence of HIV infection in men was 3.3% in Cotonou, 4.1% in Yaoundé, 19.8% in Kisumu and 23.2% in Ndola. For women, the respective figures were 3.4, 7.8, 30.1 and 31.9%. The prevalence of HIV infection among women aged 15-19 years was 23.0% in Kisumu and 15.4% in Ndola. Among women in Kisumu who had their sexual debut 5 years before the interview, the prevalence of HIV infection was 46%; in Ndola, it was 59%. Among sex workers, the prevalence of HIV infection was 57.5% in Cotonou, 34.4% in Yaoundé, 74.7% in Kisumu and 68.7% in Ndola. CONCLUSIONS: The HIV prevalence rates in the general population confirmed our preliminary assessment of the level of HIV infection in the four cities, which was based on estimates of HIV prevalence from sentinel surveillance among pregnant women. The very high prevalence of HIV infection among young women in Kisumu and Ndola calls for urgent intervention

Multicentre study on factors determining differences in rate of spread of HIV in sub-Saharan Africa: methods and prevalence of HIV infection.

OBJECTIVE: The objective of this study was to explore whether the differences in rate of spread of HIV in different regions in sub-Saharan Africa could be explained by differences in sexual behaviour and/or factors influencing the probability of HIV transmission during sexual intercourse. METHODS: A cross-sectional, population-based study was conducted in two cities with a high HIV prevalence (Kisumu in Kenya and Ndola in Zambia) and two cities with a relatively low HIV prevalence (Cotonou in Benin and Yaoundé in Cameroon). In each of these cities, approximately 1000 men and 1000 women, aged 15-49 years, were randomly selected from the general population. Consenting men and women were interviewed and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection and trichomoniasis (the latter for women only). In addition, a survey was conducted on a random sample of 300 sex workers in each city. The research instruments, including the questionnaires and the laboratory procedures, were standardized to permit comparison of results. RESULTS: The numbers of men interviewed were 1021 in Cotonou, 973 in Yaoundé, 829 in Kisumu, and 720 in Ndola. The corresponding figures for women were 1095, 1116, 1060 and 1130. In Yaoundé, Kisumu and Ndola, the response rates for men were lower than for women due to failure to make contact with eligible men. The proportion of eligible women who were interviewed was 86% in Yaoundé, and 89% in Kisumu and Ndola. In Yaoundé, 76% of eligible men were interviewed, along with 82% in Kisumu and 75% in Ndola. The prevalence of HIV infection in men was 3.3% in Cotonou, 4.1% in Yaoundé, 19.8% in Kisumu and 23.2% in Ndola. For women, the respective figures were 3.4, 7.8, 30.1 and 31.9%. The prevalence of HIV infection among women aged 15-19 years was 23.0% in Kisumu and 15.4% in Ndola. Among women in Kisumu who had their sexual debut 5 years before the interview, the prevalence of HIV infection was 46%; in Ndola, it was 59%. Among sex workers, the prevalence of HIV infection was 57.5% in Cotonou, 34.4% in Yaoundé, 74.7% in Kisumu and 68.7% in Ndola. CONCLUSIONS: The HIV prevalence rates in the general population confirmed our preliminary assessment of the level of HIV infection in the four cities, which was based on estimates of HIV prevalence from sentinel surveillance among pregnant women. The very high prevalence of HIV infection among young women in Kisumu and Ndola calls for urgent intervention

The multicentre study on factors determining the differential spread of HIV in four African cities: summary and conclusions

Not the final published versio

Multicentre study on factors determining differences in rate of spread of HIV in sub-Saharan Africa: methods and prevalence of HIV infection.

OBJECTIVE: The objective of this study was to explore whether the differences in rate of spread of HIV in different regions in sub-Saharan Africa could be explained by differences in sexual behaviour and/or factors influencing the probability of HIV transmission during sexual intercourse. METHODS: A cross-sectional, population-based study was conducted in two cities with a high HIV prevalence (Kisumu in Kenya and Ndola in Zambia) and two cities with a relatively low HIV prevalence (Cotonou in Benin and Yaoundé in Cameroon). In each of these cities, approximately 1000 men and 1000 women, aged 15-49 years, were randomly selected from the general population. Consenting men and women were interviewed and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection and trichomoniasis (the latter for women only). In addition, a survey was conducted on a random sample of 300 sex workers in each city. The research instruments, including the questionnaires and the laboratory procedures, were standardized to permit comparison of results. RESULTS: The numbers of men interviewed were 1021 in Cotonou, 973 in Yaoundé, 829 in Kisumu, and 720 in Ndola. The corresponding figures for women were 1095, 1116, 1060 and 1130. In Yaoundé, Kisumu and Ndola, the response rates for men were lower than for women due to failure to make contact with eligible men. The proportion of eligible women who were interviewed was 86% in Yaoundé, and 89% in Kisumu and Ndola. In Yaoundé, 76% of eligible men were interviewed, along with 82% in Kisumu and 75% in Ndola. The prevalence of HIV infection in men was 3.3% in Cotonou, 4.1% in Yaoundé, 19.8% in Kisumu and 23.2% in Ndola. For women, the respective figures were 3.4, 7.8, 30.1 and 31.9%. The prevalence of HIV infection among women aged 15-19 years was 23.0% in Kisumu and 15.4% in Ndola. Among women in Kisumu who had their sexual debut 5 years before the interview, the prevalence of HIV infection was 46%; in Ndola, it was 59%. Among sex workers, the prevalence of HIV infection was 57.5% in Cotonou, 34.4% in Yaoundé, 74.7% in Kisumu and 68.7% in Ndola. CONCLUSIONS: The HIV prevalence rates in the general population confirmed our preliminary assessment of the level of HIV infection in the four cities, which was based on estimates of HIV prevalence from sentinel surveillance among pregnant women. The very high prevalence of HIV infection among young women in Kisumu and Ndola calls for urgent intervention

Suppression of Ycf1p function by Cka1p-dependent phosphorylation is attenuated in response to salt stress

The yeast vacuolar membrane protein Ycf1p and its mammalian counterpart, MRP1, belong to the ABCC subfamily of ATP-binding cassette (ABC) transporters. Genetic evidence suggests that the yeast casein kinase 2α, Cka1p, negatively regulates Ycf1p function via phosphorylation of Ser251 within the N-terminus. In this study we provide strong evidence that Cka1p regulates Ycf1p function via phosphorylation of Ser251. We show that the CK2 holoenzyme interacts with Ycf1p. However, genetic analysis suggests that only Cka1p is required for Ser251 phosphorylation; as deletion of CKA1 significantly reduces Ser251 phosphorylation in vivo. Furthermore, purified recombinant Cka1p phosphorylates an Ycf1p-derived peptide containing Ser251. We also demonstrate that Ycf1p function is induced in response to high salt stress. Induction of Ycf1p function strongly correlates with reduced phosphorylation of Ser251. Importantly, Cka1p activity in vivo is similarly reduced in response to salt stress, consistent with our finding that Cka1p directly phosphorylates Ser251 of Ycf1p. We provide genetic and biochemical evidence that strongly suggests that the induction of Ycf1p function is the result of decreased phosphorylation of Ser251. In conclusion, our work demonstrates a novel biochemical role for Cka1p regulation of Ycf1p function in the cellular response of yeast to salt stress