Alcohol use among adolescents in Puerto Rico: the influence of physical and social neighborhood disorder.

INTRODUCTION: The characteristics of social settings are increasingly being recognized as important factors influencing the health of individuals. This study examines the association of neighborhood physical and social disorganization with alcohol consumption in a sample of adolescents 12- to 15-years-old residing in communities of the San Juan metropolitan area with high availability of illicit drugs. METHODS: The sampling frame was developed encompassing all census sectors in three municipalities of the San Juan metropolitan area with outdoor illegal drug-selling areas operating within them. Consent from parents and their adolescent offspring was obtained from 691 of these households for a response rate of 96%. Alcohol use was measured by asking adolescents if they had consumed alcohol during the last 12 months. Neighborhood social disorganization included hearing gunfire in the neighborhood, seeing neighbors selling stolen merchandise and drugs, vandalism, neighbors using alcohol and drugs, and seeing persons carrying weapons. Neighborhood physical disorganization included the presence of abandoned vehicles and buildings in the neighborhood, graffiti, and places where people go to inject drugs. RESULTS: Multiple logistic regression analysis revealed that older participants were more likely to use alcohol. Neighborhood social disorder was significantly associated with alcohol use. The strong positive gradient between neighborhood social disorder and alcohol use remained highly significant after controlling by sociodemographic characteristics. In contrast, neighborhood physical disorder was not significantly associated with alcohol use. CONCLUSION: These findings suggest that social signs of neighborhood disorganization have a more direct influence over adolescents' behaviors than the physical signs. Health professionals need to be cognizant of the strong effects that social environments have on adolescents and develop strategies to address these when intervening with adolescents.

Mortality among Hispanic drug users in Puerto Rico

This paper assesses mortality rate for a cohort of drug users in Puerto Rico compared with that of the Island's general population, examining causes of death and estimating relative risk of death. Date and cause of death were obtained from death certificates during 1998. Vital status was confirmed through contact with subjects, family, and friends. HIV/AIDS was the major cause of death (47.7%), followed by homicide (14.6%), and accidental poisoning (6.3%). Females had higher relative risk of death than males in all age categories. Not living with a sex partner and not receiving drug treatment were related to higher mortality due to HIV/AIDS. Drug injection was the only variable explaining relative risk of death due to overdose. Puerto Rico needs to continue developing programs to prevent HIV/AIDS among drug users. Special attention should be given to young women, who appear to be in greatest need of programs to prevent early mortality.

Molecular cloning and expression of an alpha-mannosidase gene in Mycobacterium tuberculosis.

Mannose is a major component of glycolipids and glycoproteins of the cell envelope of M. tuberculosis (Mtb). However, the enzymes involved in the biosynthesis and catabolism of mannosylated glycans are largely unknown. We demonstrate alpha-mannosidase activity towards the fluorescent substrate 4-methylumberlliferyl-alpha-D-mannopyranoside (4MU-Man) in cell lysates of attenuated and virulent Mtb bacilli, with two-fold higher activity in the virulent strain Erdman. Mannosidase activity was optimal at pH 6.5, was not inhibited by deoxymannojirimycin (dMNJ), was mildly inhibited by swainsonine (SW) and stimulated two-fold by EDTA. GenBank BLAST analysis for sequences homologous to eukaryotic alpha-mannosidases revealed a 3.6 kb putative gene (Rv0648) in Mtb cosmid SCY20H10 (Acc# z92772), with strong homology (48%) to the rat ER/cytosolic alpha-mannosidase and containing signature sequences of class 2 mannosidases. By RT-PCR, gene Rv0648 was found differentially expressed, with lower expression during growth in A549 pneumocyte cultures. Gene Rv0648 was cloned, expressed in E. coli, and alpha-mannosidase activity in cell lysates determined. Expression of alphaMan-pET in E. coli cells resulted in an eight-fold increase in mannosidase activity toward 4-MU-Man, upon IPTG induction. Partial purification of the histidine-tagged Mtb mannosidase by metal chelation affinity chromatography, and analysis by SDS-PAGE, showed a protein with the predicted m.w. of 137.5 kDa. Enzyme assays of the column fractions showed alpha-mannosidase activity toward synthetic aryl-mannose substrates, in fractions enriched in the recombinant Mtb mannosidase. These results demonstrate that gene Rv0648 encodes an active alpha-mannosidase in Mtb.

Induction of MMP-9 mediated gelatinolytic activity in human monocytic cells by cell wall components of Mycobacterium tuberculosis.

Mycobacterium tuberculosis (Mtb) infection induces the expression of host matrix metalloIproteinases (MMPs) capable of tissue degradation. We show that infection of mice with Mtb results in differential expression of MMPs in the lung. MMP-9 activity increased by week 1 post-infection, while MMP-2 activity increased after week 2. RT-PCR analysis for gene expression of gelatinases and their respective inhibitors showed: a small increase in MMP-9 by week 1, no change in TIMP-1 and MMP-2, and a significant decrease in TIMP-2 by week 4. The increase in MMP-2 could be due to a decrease in TIMP-2 expression. Addition of 4-aminophenylmercuric acid to lung extracts increased MMP-9 activity, suggesting that its regulation could be due to endogenous activation by proteases. In vitro, attenuated and virulent Mtb strains equally induced MMP-9 expression in U937 monocytes. The inducer of MMP-9 in Mtb was present in culture filtrates, and was active after paraformaldehyde fixation. LAM stimulated MMP-9 expression in THP-1 cells, but not U937 cells. However, LAM-free extracts also induced MMP-9 activity in THP-1 cells. Fractionation of Mtb extracts by chromatography revealed fractions of 17 and 156 kDa with MMP-9 inducing activity. In conclusion, LAM and other components of Mtb induce the expression of MMP-9.

Prevalence and correlates of anergy among drug users in Puerto Rico.

OBJECTIVES: This study assessed prevalence and correlates of anergy among a cohort of drug users in communities in the San Juan metropolitan area. METHODS: In all, 719 drug injectors and crack users were recruited in neighbourhoods in the San Juan metropolitan area following a stratified cluster design of 30 copping areas (places where drugs are sold). RESULTS: Slightly more than one-third of the total proportion of participants, 34.2%, were HIV positive and 30.3% anergic. Subjects with a history of incarceration, the HIV positive, and those reporting chronic illness were more likely to be anergic than those subjects without these characteristics. CONCLUSIONS: Most studies addressing drug users' immune system dysfunction are related to HIV infection. Additional studies are needed to provide a more comprehensive understanding of drug users' immune systems.

Factors associated with changes in sex behaviour among drug users in Puerto Rico.

Despite available strategies to prevent sex risk behaviours in Puerto Rico, heterosexual transmission of HIV continues to increase. Since 1990, heterosexual contact has been the fastest growing infection risk category among the island's general population, and the primary transmission route for women and children. To understand change in sex risk behaviours and factors related to change, 911 drug injectors and 359 crack smokers were recruited from the San Juan metropolitan area following a stratified cluster design. This study comprised a total of 1,004 (79.1%) drug users who were assessed at follow-up. Abstinence from sex behaviour increased from 54.6% to 61.1% (p < 0.01), use of condoms during vaginal sex also increased from 26.4% to 36.9% (p < 0.01). In multivariate analysis, significant predictors of abstinence were gender, injection drug use, HIV seropositivity and not having a steady partner. Predictors of using condoms during vaginal sex were HIV seropositivity, STD diagnosis and participation in an HIV preventive programme. These findings indicate that additional HIV preventive efforts are needed to reduce sex risk behaviours among drug users who have a steady sex partner, as well as among drug users who are HIV-negative.

PIP: Factors associated with changes in HIV risk behaviors were investigated in a prospective study of 911 injecting drug users and 359 crack smokers recruited on the basis of a stratified cluster design in metropolitan San Juan, Puerto Rico, in 1992-93. The findings presented in this paper are based on the 1004 drug users (79.1%) who were available for a follow-up interview 6 months after the baseline interview. Respondents were randomly assigned to receive a standard HIV prevention intervention (pretest counseling, optional HIV testing, and provision of HIV results) or the standard intervention plus a site-specific enhanced intervention entailing access to condoms and needle hygiene equipment, development of a personal risk reduction plan and training in the skills required to implement it, and ongoing contact with outreach workers. Overall, abstinence from sexual behavior increased from 54.6% at baseline to 61.1% at follow-up (p 0.01) while condom use during vaginal sex rose from 26.4% to 36.9% (p 0.01). In multivariate analysis, significant predictors of abstinence were male gender, injecting drug use, a positive HIV test at baseline, and not having a steady partner. Significant predictors of condom use were HIV seropositivity and a sexually transmitted disease diagnosis. Participation in the enhanced compared to the standard HIV prevention program was associated with an odds ratio of 1.29 (95% confidence interval, 0.95-1.74) for abstinence and 1.97 (95% confidence interval, 1.18-3.29) for condom use in vaginal sex.

Risk behaviors, HIV seropositivity, and tuberculosis infection in injecting drug users who operate shooting galleries in Puerto Rico.

This study was designed to assess HIV risk behaviors, HIV seroprevalence, and tuberculosis (TB) infection in shooting gallery managers in Puerto Rico. The subjects were 464 injection drug users (IDUs), of whom 12.5% reported managing shooting galleries. The median frequency of drug injection was higher in shooting gallery managers than in nonmanagers. A trend was observed for purified protein derivative (PPD) reactivity to increase according to the length of time spent as a gallery manager, but this trend was not statistically significant. However, anergy rates increased significantly with increase in the number of months spent as shooting gallery manager (p = .021). Multivariate analyses showed that IDUs reporting shooting gallery management experience of > or = 25 months were more likely to be infected with HIV. Prevention programs need to emphasize strategies to protect the health of shooting gallery clients and, in particular, shooting gallery managers. Additional studies are required to determine effective strategies for reducing the risk of HIV and TB infection in shooting galleries.

PIP: Little information is currently available on the health status of individuals who manage the settings in which drug injection-related behaviors occur. The present study investigated HIV risk behaviors, HIV seroprevalence, and tuberculosis infection among 464 injecting drug users recruited from areas in San Juan, Puerto Rico, known to have high levels of drug activity. 58 respondents (12.5%) reported having been a shooting gallery manager, for a median duration of 18 months. Managers were more likely to be female, over 35 years of age, not married, homeless, to inject only cocaine, to inject more frequently, to have a history of incarceration, and to report disability than drug users who were not managers. No differences in rates of HIV, tuberculosis, or anergy existed between managers with 1-24 months of management experience and nonmanagers. However, gallery managers with 25 or more months of experience were nearly 3 times more likely to be infected with HIV, nearly 2 times more likely to be anergic, and 2.5 times more likely to have tuberculosis than nonmanagers. 41% of nonmanagers, 48% of managers with 1-24 months of experience, and 71% of those who had been managers for 25 months or more were HIV-seropositive. The compromised health status of long-term shooting gallery managers underscores the need for public health interventions to interrupt the spread of sexually transmitted diseases, HIV, and tuberculosis in this high-risk setting.

Identification of genes differentially expressed in Mycobacterium tuberculosis by differential display PCR.

RNA arbitrarily-primed differential display PCR (RAP-PCR) was used to identify and isolate genes differentially expressed between attenuated (H37Ra) and virulent (H37Rv, Erdman) laboratory strains of Mycobacterium tuberculosis (Mtb). Using this method, cDNA fragments showing homology to three known mycobacterial genes and six putative novel genes in mycobacterial cosmid vectors were identified. Among the putative novel Mtb genes identified, we found: (1) gene MTV041.29, containing multiple tandem repetitive sequences and encoding a putative Gly-, Ala, Asn-rich protein (PPE family); (2) gene MTV004.03, containing the AT10S repetitive gene sequence; (3) gene MTV028.09, encoding a hypothetical protein of unknown function; (4) genes MTCY78.20,21, possibly encoding two hypothetical proteins of unknown function; (5) gene MTCY01A6.09, encoding a putative novel ferrodoxin dependent glutamate synthase; and (6) gene MTCY31.20, encoding a putative cyclohexanone monooxygenase. Using gene specific primers in a second differential display PCR and by RT-PCR amplification, novel genes 1, 2, 3 and 4 were shown to be differentially up-regulated in the attenuated Mtb strain H37Ra compared to H37Rv and Erdman strain. Overall, we demonstrated that RAP-PCR, as a first step, is a quick and sensitive method for the identification and isolation of novel genes expressed in Mtb. Because of limitations inherent to the lack of specificity of arbitrary primers in the RAP-PCR method, a second differential display PCR and RT-PCR amplification with gene-specific primers was necessary in order to confirm differential expression of the identified genes.

Syringe and needle exchange as HIV/AIDS prevention for injection drug users in Puerto Rico.

This study evaluated the effectiveness of the first needle exchange program (NEP) established in Puerto Rico. The data for this study were collected during the first months of the NEP from July 1995 to March 1996 in 13 communities of the San Juan metropolitan area. Subjects were the participants of two modalities of the NEP: a mobile team and a community-based drug treatment program. During the 3-week evaluation period, 2401 injection drug users (IDUs) were recruited, resulting in a total of 19,195 exchange contacts and 146,323 syringes exchanged. No significant change in drug injection was observed. However, the program was effective in reducing sharing of syringes and cookers. The study suggests that the NEP did help in reducing needle sharing in Puerto Rico. However, the HIV seropositivity in returned syringes suggests the need to continue aggressive prevention programs to arrest the epidemic among IDUs. However, factors related to the socio-cultural environment as well as cultural norms and traditions need to be considered when planning and expanding NEPs.

Behavioral effects of receiving HIV test results among injecting drug users in Puerto Rico.

OBJECTIVES: To examine the influence of knowledge of HIV serostatus on changes in risk behaviors among injecting drug users (IDU). PROCEDURES: IDU were recruited through sampling conducted at street drug-selling areas. Of 374 participants, 88.8% consented to be HIV tested and returned for their test results, and 73.5% were relocated and interviewed 6 months later. RESULTS: Of the 176 IDU who reported a seronegative test result prior to baseline, 29 tested seropositive at baseline. No significant differences were found between HIV-positive and HIV-negative IDU in needle risk behaviors. HIV-positive IDU were significantly less likely to report being sexually active [odds ratio (OR), 0.41 : 95% confidence interval (CI), 0.22-0.75] and more likely to use condoms during vaginal (OR, 4.43; 95% CI, 1.48-13.29) and oral sex (OR, 6.67; 95% CI, 1.42-31.33). CONCLUSION: The findings of this study show the importance of encouraging IDU to undergo periodic retesting. HIV testing could have an important role in reducing heterosexual transmission from IDU.

Crack use in Puerto Rico: evidence of a recent epidemic.

This study examines the prevalence of crack use among out-of-treatment drug users in the San Juan metropolitan area. Of the sample of 849 drug users, 310 (36.5%) were crack users only, 179 (21.1%) were drug injectors and crack users, and 360 (42.4%) were drug injectors only. To study the characteristics of crack users we selected the subjects who reported the use of crack only. Of the 310 subjects, 193 (62.3%) men and 117 (37.7%) women, the mean age was 29 years. Significant differences were observed by gender. Females reported higher education, living in a nuclear family, crack/cocaine as the first drug used, history of sexually transmitted diseases and higher rates of HIV seropositivity. Males were more likely to report income from illegal activities, incarceration, use of multiple drugs, and more years of drug use. Among those sexually active, females were more likely to practice unprotected vaginal sex, have multiple sex partners, engage in prostitution (exchange of sex for money and/or drugs) and use condoms.

Mycobacterium tuberculosis infection among crack and injection drug users in San Juan, Puerto Rico.

This study aims to determine the prevalence of Mycobacterium tuberculosis infection and its association with HIV and other health risk factors among drug users. A sample of 716 IDUs and crack users were enrolled from community sites. Consenting subjects were tested for HIV serum antibody status. Drug users with an unknown PPD status were administered a PPD skin test and an anergy panel of three antigens (Candida, mumps and tetanus). Overall, 68 (10.3%) were reactive to the PPD skin test, 240 (34.7%) were HIV positive and 195 (29.5%) showed cutaneous anergy. Participants infected with tuberculosis (TB) were more likely to be HIV seropositive, and to have a history of incarceration and residential drug treatment than those not infected. In addition, TB infection was more prevalent among intravenous drug users (IDUs) and shooting gallery managers. These findings suggest that drug users should be considered at high risk for TB and HIV infection. Innovative programs to monitor both infections among drug users are needed to arrest what can become a dual epidemic of HIV and TB in the near future.

Crack use in Puerto Rico: evidence of a recent epidemic

This study examines the prevalence of crack use among out-of-treatment drug users in the San Juan metropolitan area. Of the sample of 849 drug users, 310 (36.5 percent) were crack users only, 179 (21.1 percent) were drug injectors and crack users, and 360 (42.4 percent) were drug injectors only. To study the characteristics of crack users we selected the subjects who reported the use of crack only. Of the 310 subjects, 193 (62.3 percent) men and 117 (37.7 percent) women, the mean age was 29 years. Significant differences were observed by gender. Females reported higher education, living in a nuclear family, crack/cocaine as the first drug used, history of sexually transmitted diseases and higher rates of HIV seropositivity. Males were more likely to report income from illegal activities, incarceration, use of multiple drugs, and more years of drug use. Among those sexually active, females were more likely to practice unprotected vaginal sex, have multiple sex partners, engage in prostitution (exchange of sex for money and/or drugs) and use condoms

Mycobacterium tuberculosis infection among crack and injection drug users in San Juan, Puerto Rico

This study aims to determine the prevalence of Mycobacterium tuberculosis infection and its association with HIV and other health risk factors among drug users. A sample of 716 IDUs and crack users were enrolled from community sites. Consenting subjects were tested for HIV serum antibody status. Drug users with an unknown PPD status were administered a PPD skin test and an anergy panel of three antigens (Candida, mumps and tetanus). Overall, 68 (10.3 percent) were reactive to the PPD skin test, 240 (34.7 percent) were HIV positive and 195 (29.5 percent) showed cutaneous anergy. Participants infected with tuberculosis (TB) were more likely to be HIV seropositive, and to have a history of incarceration and residential drug treatment than those not infected. In addition, TB infection was more prevalent among intravenous drug users (IDUs) and shooting gallery managers. These findings suggest that drug users should be considered at high risk for TB and HIV infection. Innovative programs to monitor both infections among drug users are needed to arrest what can become a dual epidemic of HIV and TB in the near future

Effects of HIV testing and counseling on reducing HIV risk behavior among two ethnic groups.

PIP: The impact of an HIV testing and counseling program on the risk behaviors of drug users was assessed in 981 African American heroin and crack cocaine users living in the US and 144 Puerto Ricans living both in Puerto Rico and the US. Respondents were part of the US National Institute on Drug Abuse's multi-site Cooperative Agreement for Acquired Immunodeficiency Syndrome Community-Based Outreach/Intervention Research. At each site, active drug injectors and crack cocaine users were selected by targeted sampling methods. The intervention included pre-HIV test counseling, voluntary HIV testing, a post-testing counseling session focused on risk-reduction strategies, and an optional session for HIV-positive participants. The mean age of respondents was 38.5 years; 82.9% were unemployed. 62.5% had a history of sexually transmitted diseases and 12.5% (9.3% of African Americans and 31.9% of Puerto Ricans) were HIV-positive. At baseline, 63.5% of African Americans and 47.2% of Puerto Ricans were engaging in unprotected vaginal intercourse and 3.1% and 8.3%, respectively, were practicing unprotected anal intercourse. Injection risk factors after counseling were independent of HIV test result among African Americans; among Puerto Ricans, a positive HIV test increased the likelihood of shared use of cookers. In both ethnic groups, seropositives were significantly less likely to persist in practicing unprotected vaginal sex. Seropositive African Americans were also less likely to continue to practice unprotected oral sex. Since heterosexual relations with an HIV-positive drug user is a major risk factor for sex partners and children, this screening and counseling program can have a substantial impact on control of the AIDS epidemic in the US.^ieng

Incarceration history as a risk factor for HIV infection among Puerto Rican injection drug users.

This study assesses factors associated with incarceration history and HIV seropositivity among 1,700 out-of-treatment drug injectors recruited in Puerto Rico between 1989-1990 from health care centers, emergency rooms, copping areas, shooting galleries, bars, billiard rooms and street corners. Analysis links incarceration history with criminal involvement and chronic drug use. After controlling for sociodemographics and previously reported correlates of HIV status, regression analysis shows incarceration history significantly relates to HIV status. The only predictor of incarceration history not related to HIV status was illegal activity as a major source of income. Analysis emphasizes HIV prevention programs within the penal system.

Expression and purification of the alpha and beta subunits of Drosophila casein kinase II using a baculovirus vector.

Two recombinant baculoviruses that express the alpha and beta subunits of Drosophila melanogaster casein kinase II, respectively, have been constructed. The expressed proteins are similar to the authentic Drosophila subunits in size and are recognized by antisera raised against the Drosophila holoenzyme. Extracts derived from cells infected with the alpha subunit-expressing virus display elevated casein kinase II activity in vitro. This activity is markedly enhanced in extracts of cells infected with both viruses, or when alpha and beta subunit-containing extracts are mixed in vitro following lysis. Recombinant holoenzyme and the alpha subunit were purified to near homogeneity using phosphocellulose column chromatography. The specific activity of the purified recombinant holoenzyme was very similar to that of the native enzyme, and was fivefold higher than that of the purified free alpha subunit. The Stokes radius of the recombinant holoenzyme was estimated to be 50 A, a value similar to that reported for the native enzyme, whereas the alpha subunit demonstrated a Stokes radius of 26.5 A. Studies using sucrose density gradient centrifugation showed that, under conditions of high ionic strength, the quaternary structure of the purified holoenzyme was tetrameric (like the native enzyme), whereas the structure of the alpha subunit was monomeric. At lower ionic strength the recombinant holoenzyme had a significantly higher sedimentation coefficient, characteristic of the formation of filaments found for the native enzyme. Interestingly, the purified catalytic subunit also displayed a higher S value under conditions of low ionic strength, revealing the formation of alpha subunit aggregates.

Behavioral risk factors and human immunodeficiency virus (HIV) prevalence among intravenous drug users in Puerto Rico.

This study reports on four empirical models likely to contribute to understanding the behaviors linked with human immunodeficiency virus (HIV) among intravenous drug users. The sample comprises 1,637 intravenous drug users recruited between May 1989 and June 1990 in San Juan, Puerto Rico. Adjusting for sociodemographics, four logistic regression models were constructed to assess the association of risk behaviors with HIV seropositivity. In model 1, the variables found to be significantly associated with HIV seropositivity were injecting four times a day, injection as the only route of consuming drugs, and years of injection. In model 2, the only risk behavior significantly associated with HIV seropositivity was injecting drugs in shooting galleries. In model 3, all sex risk variables failed to meet the adjusted level of significance. In model 4, pneumonia, hepatitis, and syphilis were significantly linked with HIV infection. In order to assess the individual effects of the significant variables in each one of the four models, a logistic regression analysis was performed simultaneously controlling for all of the variables. After adjustment for the Bonferroni correction, age group 25-34 years, injection as the only route of using drugs, number of years of injection, and syphilis were the only significant variables remaining.

AIDS risk behavior patterns among intravenous drug users in Puerto Rico and the United States.

We interviewed 385 IV drug users recruited in the streets of the San Juan metropolitan area and compared our findings with comparable results from projects in the United States. As expected, intravenous (IV) drug users, irrespectively of the race or ethnic group they belong to or the geographical setting in which they live, are still practicing HIV risk behaviors. Overall, IV drug users in this analysis are young, however, both Puerto Rican and Hispanic groups have completed less years of school than Blacks and Whites in the United States. The fact that almost half of Puerto Rican IV drug users in the United States reported illegal activities as a source of income surprised investigators. However, as hypothesized by investigators, almost half of the Island's IV drug users reported to live with parents. Puerto Rican IV drug users are still practicing HIV risk behaviors, they inject drugs and use shooting galleries to inject drugs more frequently, and are less likely to clean needles and use condoms than Puerto Ricans in the U.S., Blacks and Whites. It is a well known fact that intravenous drug users are the largest group at risk for the acquired immunodeficiency syndrome (AIDS) in Puerto Rico and among Puerto Ricans in the United States. IV drug users are also the major risk for heterosexual transmission and main source of perinatal transmission of the disease. Thus, resources for preventing AIDS in Puerto Rico are needed most among IV drug users, where 44.5 of the subjects in this study are HIV positive.

Schistosoma mansoni contains a galactosyltransferase activity distinct from that typically found in mammalian cells.

It has been reported previously that some complex-type Asn-linked oligosaccharides contained in glycoproteins synthesized by Schistosoma mansoni adult males contain terminal galactosyl residues. We report here that extracts from S. mansoni adult male and female worms contain a beta 1,4-galactosyltransferase activity that transfers galactose from the donor substrate UDP-galactose to the acceptor substrate N-acetylglucosamine in a beta 1,4-linkage position to form the disaccharide Gal beta 1,4GlcNAc. In this respect the schistosome-derived activity is similar to that commonly found in mammalian tissues. The kinetic properties, however, of the common beta 1,4-galactosyltransferase activity in mammalian tissues are dramatically altered in the presence of the modifier protein alpha-lactalbumin, whereas the beta 1,4-galactosyltransferase activities in adult male and female schistosomes are not altered by this modifier. Overall, our results demonstrate that adult schistosomes contain a beta 1,4-galactosyltransferase activity and that it is unlike that commonly found in mammalian tissues.