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'Intravention,' prevention activities that are conducted by and sustained through ongoing actions of members of communities-at-risk, is an appropriate goal for HIV intervention activities. Data from 120 injection drug users in a Brooklyn, New York, neighborhood that has seen decreases in HIV prevalence among IDUs and little HIV diffusion to young adults indicate that most of them have recently (3 months) urged other people to engage in one or more self-protective actions. These data suggest that the common image of IDUs as simply being sources of social and medical problems is inaccurate. Research is needed into how to create and diffuse 'communities of intravention; ' and we suggest that behavioral interventions be evaluated for their success or failure at creating outward-focused health communication by participants as well as for their impact on individual risk behaviors. [ABSTRACT FROM AUTHOR]

A previously published medium has been found to be effective for plant regeneration from leaf expiants of Solanum tuberosum cv. Katahdin. A number of combinations of thidiazuron and naphthaleneacetic acid, along with a medium previously published for shoot regeneration from protoplast-derived calli of Solanum phureja, which contained zeatin, indoleacetic acid and gibberellic acid (ZIG), were tested for callus induction, and all calli were transferred to ZIG for shoot induction. We conclude that leaf expiants cultured on ZIG medium at all stages of culture were the most effective at shoot production. A mean of over six shoots were produced per expiant after four months in culture. [ABSTRACT FROM AUTHOR]

Abstract Background In some countries, "Big Events" like crises and transitions have been followed by large increases in drug use, drug injection and HIV/AIDS. Argentina experienced an economic crisis and political transition in 2001/2002 that affected how people use their time. This paper studies how time use changes between years 2001 and 2004, subsequent to these events, were associated with drug consumption in poor neighbourhoods of Greater Buenos Aires. Methods In 2003-2004, 68 current injecting drug users (IDUs) and 235 young non-IDUs, aged 21-35, who lived in impoverished drug-impacted neighbourhoods in Greater Buenos Aires, were asked about time use then and in 2001. Data on weekly hours spent working or looking for work, doing housework/childcare, consuming drugs, being with friends, and hanging out in the neighbourhood, were studied in relation to time spent using drugs. Field observations and focus groups were also conducted. Results After 2001, among both IDUs and non-IDUs, mean weekly time spent working declined significantly (especially among IDUs); time spent looking for work increased, and time spent with friends and hanging out in the neighbourhood decreased. We found no increase in injecting or non-injecting drug consumption after 2001. Subjects most affected by the way the crises led to decreased work time and/or to increased time looking for work--and by the associated increase in time spent in one's neighbourhood--were most likely to increase their time using drugs. Conclusions Time use methods are useful to study changes in drug use and their relationships to every day life activities. In these previously-drug-impacted neighbourhoods, the Argentinean crisis did not lead to an increase in drug use, which somewhat contradicts our initial expectations. Nevertheless, those for whom the crises led to decreased work time, increased time looking for work, and increased time spent in indoor or outdoor neighbourhood environments, were likely to spend more time using drugs. These data suggest that young adults in traditionally less-impoverished neighbourhoods may be more vulnerable to Big Events than those in previously drug-impacted impoverished neighbourhoods. Since Big Events will continue to occur, research on the pathways that determine their sequelae is needed.

We described drug use, sex risk, and STI/HIV among men who have sex with men and women (MSMW) and their female partners. We used the Network, Norms and HIV/STI Risk among Youth (NNAHRAY) study to evaluate drug use, sex risk, and biologically-confirmed STI/HIV in (1) MSMW and men who had sex with men only (MSMO) versus men who had sex with women only (MSWO) and (2) female partners of MSMW versus female partners of MSWO (N = 182 men, 152 women). MSMW versus MSWO had 30 to 60% increased odds of substance use, over twice the odds of multiple partnerships, and almost five times the odds of sex trade and HIV infection. Female partners of MSMW versus female partners of MSWO had approximately twice the odds of substance use and 1.5-2 times the odds of multiple partnerships and sex trade. Interventions should address STI/HIV risk among MSMW and their female partners.

Objectives: We examined the link between incarceration and sexually transmitted infection (STI), including HIV, from a social network perspective., Methods: We used data collected during a social network study conducted in Brooklyn, NY (n = 343), to measure associations between incarceration and infection with herpes simplex virus-2, chlamydia, gonorrhea, and syphilis or HIV and sex with an infected partner, adjusting for characteristics of respondents and their sex partners., Results: Infection with an STI or HIV was associated with incarceration of less than 1 year (adjusted prevalence ratio [PR] = 1.33; 95% confidence interval [CI] = 1.01, 1.76) and 1 year or longer (adjusted PR = 1.37; 95% CI = 1.08, 1.74). Sex in the past 3 months with an infected partner was associated with sex in the past 3 months with 1 partner (adjusted PR = 1.42; 95% CI = 1.12, 1.79) and with 2 or more partners (adjusted PR = 1.85; 95% CI = 1.43, 2.38) who had ever been incarcerated., Conclusions: The results highlight the need for STI and HIV treatment and prevention for current and former prisoners and provide preliminary evidence to suggest that incarceration may influence STI and HIV, possibly because incarceration increases the risk of sex with infected partners.

Introduction: The Centers for Disease Control and Prevention (CDC) advise repeat HIV testing for partners of HIV-infected persons; injection drug users and their sex partners; individuals with recent multiple partnerships and their sex partners; those involved in sex trade; and men who have sex with men. Additional social and behavioral variables may be useful for identifying priority populations., Methods: We analyzed data collected during a social network study conducted in a Brooklyn, NY, neighborhood to identify social and behavioral characteristics of respondents (N = 343) involved in HIV-discordant, herpes simplex virus-2- discordant, and chlamydia-discordant partnerships., Results: HIV partnership discordance was associated with injection drug use but was generally not associated with sexual behaviors including multiple partnerships and sex trade. herpes simplex virus-2 and chlamydia partnership discordance were associated with multiple partnerships, sex trade, and same sex partnership history. Additional correlates of sexually transmitted infection (STI)/HIV-discordant partnerships included older age (>or=25 years), noninjection drug use, and incarceration history. Analyses suggested that screening tools composed of CDC-recommended sexual risk and injection drug indicators plus indicators of older age, noninjection drug use, and incarceration were more effective in identifying STI/HIV priority populations than tools composed of CDC indicators alone., Conclusions: Screening tools that include social and behavioral indicators may improve STI/HIV case-finding effectiveness.

Objectives: To describe: (a) the prevalence and individual and network characteristics of group sex events (GSEs) and GSE attendees; and (b) HIV/sexually transmitted infection (STI) discordance among respondents who said they went to a GSE together., Methods and Design: In a sociometric network study of risk partners (defined as sexual partners, persons with whom respondents attended a GSE, or drug injection partners) in Brooklyn, NY, we recruited a high-risk sample of 465 adults. Respondents reported on GSE attendance, the characteristics of GSEs, and their own and others' behaviors at GSEs. Sera and urines were collected, and STI prevalence was assayed., Results: Of the 465 participants, 36% had attended a GSE in the last year, 26% had sex during the most recent of these GSEs, and 13% had unprotected sex there. Certain subgroups (hard drug users, men who have sex with men, women who have sex with women, and sex workers) were more likely to attend and more likely to engage in risk behaviors at these events. Among 90 GSE dyads, in which at least 1 partner named the other as someone with whom they attended a GSE in the previous 3 months, STI/HIV discordance was common [herpes simplex virus (HSV-2): 45% of dyads, HIV: 12% of dyads, and chlamydia: 21% of dyads]. Many GSEs had 10 or more participants, and multiple partnerships at GSEs were common. High attendance rates at GSEs among members of large networks may increase community vulnerability to STI/HIV, particularly because network data show that almost all members ofa large sociometric risk network either had sex with a GSE attendee or had sex with someone who had sex with a GSE attended., Conclusions: Self-reported GSE attendance and participation were common among this high-risk sample. STI/HIV discordance among GSE attendees was high, highlighting the potential transmission risk associated with GSEs. Research on sexual behaviors should incorporate measures of GSE behaviors as standard research protocol. Interventions should be developed to reduce transmission at GSEs.

People in high-risk neighbourhoods try to protect their friends, neighbours, relatives and others from the social and physical risks associated with sex and drug use. This paper develops and validates a community-grounded questionnaire to measure such 'intravention' (health-directed efforts to protect others). An initial ethnography, including life-history interviews and focus groups, explored the forms of intravention activities engaged in by residents of Bushwick (a high-risk New York City neighbourhood). Grassroots categories of intraventions were derived and questions developed to ask about such behaviours. Face validity and adequacy of the questions were assessed by independent experts. Pre-testing was conducted, and reliability and validity were assessed. An instrument including 110 intravention items was administered to 57 community-recruited residents. Analysis focused on 57 items in 11 domain-specific subscale. All subscales had good to very good reliability; Cronbach's alpha ranged from .81 to .95. The subscales evidenced both convergent and discriminant validity. Although further testing of this instrument on additional populations is clearly warranted, this intravention instrument seems valid and reliable. It can be used by researchers in comparative and longitudinal studies of the causes, prevalence and affects of different intravention activities in communities. It can benefit public health practitioners by helping them understand the environments in which they are intervening and by helping them find ways to cooperate with local neighbourhood-level health activists.

Risk networks can transmit HIV or other infections; social networks can transmit social influence and thus help shape norms and behaviors. This primarily-theoretical paper starts with a review of network concepts, and then presents data from a New York network study to study patterns of sexual and injection linkages among IDUs and other drug users and nonusers, men who have sex with men, women who have sex with women, other men and other women in a high-risk community and the distribution of HIV, sex at group sex events, and health intravention behaviors in this network. It then discusses how risk network microstructures might influence HIV epidemics and urban vulnerability to epidemics; what social and other forces (such as "Big Events" like wars or ecological disasters) might shape networks and their associated norms, intraventions, practices and behaviors; and how network theory and research have and may continue to contribute to developing interventions against HIV epidemics.

"Social capital" has been critiqued as distracting attention from inequalities and policies that produce ill health. We support this critique insofar as social capital refers to the degree of trust and consensus in a locality, but find value in another dimension often included in the concept of social capital--social network ties and their associated communication patterns. We present a case study of Bushwick, a community of 100,000 people in Brooklyn NY, to suggest that the network aspect of "social capital" is useful to understand the active, on-the-ground processes by which residents of some neighborhoods beset by poverty, racial/ethnic subordination, and internal divisions (that themselves arise from inequalities and state policies) work out ways to defend their own and others' safety and health. We use a combination of population-representative survey data for young adults; sexual network survey data; and ethnography to show that Bushwick residents (including drug users and dealers) have used social network ties, communication, and normative pressures to reduce the extent to which they are put at risk by the drug trade and by drug-use-related HIV/AIDS in spite of conflicting interests, disparate values, and widespread distrust both of other community members and of dominant social institutions. This was done by "intravention" health communications, development of protective norms, informal negotiations, and other forms of adjustments within and among various groups--but it occurred in the absence of trust or consensus in this community. We conclude both (1) that social network interpretations of "social capital" might be better conceptualized in dialectic terms as collective action to survive in a harsh social order, and (2) that the social capital theory emphasis on trust and consensus as important causal factors for lowering drug-related risks at the community level may be a romanticized and erroneous perspective.

Cerato-ulmin, a hydrophobic protein produced by the Dutch elm disease fungus Ophiostoma ulmi, is toxic to susceptible elms. The physiological role of this protein may be related to its location on hyphal surfaces. Cerato-ulmin is a member of the hydrophobins, proteins used in the formation of structures involved in asexual reproduction (sporulation and conidiation).

Transgenic creeping bentgrass (Agrostis palustris Huds., cv. Pencross; Poaceae) plants have been obtained by microprojectile bombardment of and regeneration from embryogenic calli with a vector designed to deliver the β-glucuronidase (GUS) gene under the control of rice actin 1 5' regulatory sequences. Southern analysis of polymerase chain reaction (PCR)-amplified and restriction-digested genomic DNA of four transgenic plants regenerated from these cultures showed the unscrambled integration of the gus fragment. Northern blot analysis confirmed the expression of gus mRNA in one of the transgenic plants. Western blot analysis revealed a high level of accumulation of gus protein. Histochemical assays showed enzymatic activity of β-glucuronidase in all parts of the transgenic turfgrass plant. The order of gus expression level in different tissues of the transgenic plant is as follows: stem node > first young leaf > root tip > second / third / fourth young leaf > stem internode > root hair-zone.

The carboxy-terminus of the gamma chain of fibrinogen contains a sequence which is believed to be one of the domains that interacts with glycoprotein (GP) IIb/IIIa to support platelet aggregation. A normal variant of fibrinogen exists in which the four carboxy-terminal amino acids are replaced by 20 amino acids. This variant, known as gamma', has been reported to bind less effectively to platelets. The purpose of the present study was to engineer novel proteins to determine what differences in amino acid sequence between the gamma and gamma' chains influence the interaction of the carboxyterminus with GPIIb/IIIa. In this regard, the gamma chain cDNA in a bacterial plasmid expression vector was modified by oligonucleotide-directed mutagenesis to produce recombinant gamma chains with amino acid changes in the carboxy-terminus which reflect the differences between gamma and gamma'. The recombinant gamma chain with an unmodified carboxy-terminus supported adenosine diphosphate (ADP)-induced platelet aggregation to the same extent as intact fibrinogen. In contrast, the ability of gamma' 427 (the recombinant gamma' variant) and gamma 427 (where the 16 amino acid gamma' extension [412-427] was added to the carboxy-terminus of gamma) to support platelet aggregation was markedly reduced. In addition, the extent of ADP-induced platelet aggregation was decreased in the presence of gamma' 411 (where amino acids 408-411 in gamma were replaced with amino acids 408-411 in gamma'), while gamma 407 (where the four carboxy-terminal amino acids were deleted) was not capable of supporting aggregation. These findings demonstrate that the four residues AGDV are not only required but must be carboxy-terminal to support platelet aggregation.

The fungal toxin associated with Dutch elm disease, cerato-ulmin, has been produced in the bacterium Escherichia coli by the assembly of oligonucleotides according to the unpublished amino acid sequence of the toxin. This toxin was produced at approximately 80 micrograms/L of cell culture as a fusion to glutathione S-transferase. We synthesized the toxin as a fusion protein to improve purification and stability. Recombinant cerato-ulmin was analyzed by immunoblot analysis and then separated from its fusion partner by thrombin. We incorporated this molecule into an appropriate medium to test the activity of the toxin on the growth of American elm callus cultures.

The US Environmental Protection Agency is developing regulations for various drinking water disinfection by-products (DBPs). This effort involves developing analytical methods for the DBPs formed as a result of different disinfection treatments and collecting occurrence data for these species. Ion chromatography is one method being used to analyze drinking water samples for the following inorganic DBPs: chlorite, chlorate and bromate. These anions, however, are difficult to separate from common interfering anions of chloride, carbonate and nitrate. A method is therefore presented by which tetraborate/boric acid is used to separate these anions. Method detection limits of the order of 10 micrograms/l, using conductivity and UV detection were obtained. Stability studies of chlorite showing the effectiveness of ethylenediamine as a preservative and summary data for an occurrence of nitrite, nitrate and the DBP precursor bromide are presented.

We have produced human fibrinogen gamma 259-411 in Escherichia coli in order to study the relationship between the calcium binding activity of the polypeptide and the integrity of the disulfide bond cysteine326-cysteine339. The polypeptide was produced from a plasmid expression vector at approximately 5 micrograms per milliliter of bacterial culture. The identity of the polypeptide was confirmed by N-terminal amino acid sequence analysis. The expression vector was modified by oligonucleotide directed mutagenesis to remove the nucleotides encoding cysteines gamma 326 and gamma 339. The calcium binding activity of wild-type and altered polypeptides were compared using a solid phase assay. Our results indicate that removal of the two cysteine residues had no appreciable effect on calcium binding activity. We conclude that the integrity of the disulfide bond cysteine326-cysteine339 is not critical for calcium binding to gamma 259-411.

This investigation has shown that crystalline silica has been identified as being present in the Mount St. Helens volcanic ash at levels of 3 to 7 per cent by weight. This identification has been established using X-ray powder diffraction, infrared spectrophotometry, visible spectrophotometry, electron microscopy, and Laser Raman spectrophotometry. Quantitative analysis by IR, XRD, and visible spectrophotometry requires a preliminary phosphoric acid digestion of the ash sample to remove the plagioclase silicate material which interferes with the determination by these methods. Electron microscopic analysis as well as Laser Raman spectrophotometric analysis of the untreated ash confirms the presence of silica and at levels found by the XRD and IR analysis of the treated samples. An interlaboratory study of volcanic ash samples by 15 laboratories confirms the presence and levels of crystalline silica. Although several problems with applying the digestion procedure were observed in this hastily organized supply, all laboratories employing the digestion procedure reported the presence of crystalline silica. These results unequivocally put to rest the question of the presence of silica in the volcanic ash from eruptions of Mount St. Helens in 1980.

Many chemicals, when mixed, can produce potentially hazardous effects which are harmful to human health and to the environment such as heat, pressure, fire, explosion, violent reaction, and toxic dusts, mists, fumes, and/or gases. Waste chemicals handled on a remedial action site are analyzed by simple chemical methods for compatibility. Because it is difficult to base worker and community protection programs on this limited knowledge of material content, extreme precautions must be taken to ensure safety to all working on or living near hazardous waste remedial action sites. The approach used in this study involved the application of Fourier transform infra-red spectroscopy (FTIR) to the analysis of samples taken from the Chem-Dyne remedial action hazardous waste site. The data generated are compared to the results obtained using compatibility and GC-MS analysis procedures. Illustrations are given of improved personal protection strategies, based on drum material composition obtainable by FTIR. The requirements for further testing are defined.

The human fibrinogen B beta chain was expressed in Escherichia coli to study the functions of fibrinogen associated with this subunit. Recombinant B beta chains were expressed at 100 ng/mL in an IPTG-dependent manner. A first cistron sequence, inserted into the expression vector 5' to the B beta chain cDNA, was required to express the protein. Recombinant B beta chains were expressed within five minutes after induction with IPTG and were soluble in physiologic buffers. The recombinant B beta chains migrated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) at a rate identical to B beta chains from fibrinogen treated with N-glycanase. Recombinant B beta chains were cleaved by thrombin, as demonstrated by the loss of cross-reactivity with a monoclonal antibody (MoAb) specific for the undigested B beta 1-42 fragment. The levels of expression of the B beta chain were much lower than those reported previously for the gamma chain of fibrinogen expressed in a similar vector in E coli. However, these levels are sufficient to allow further characterization of this fibrinogen subunit.

Human fibrinogen gamma chain has been expressed intact at high levels in Escherichia coli. The construction of the expression plasmid, p253, is described. Synthesis of the recombinant protein is isopropyl-beta-D-thiogalactopyranoside-dependent and is driven by the tac promoter. Western analysis of E. coli lysates demonstrates a novel protein of approx. 45 kDa which cross-reacts with antisera to human fibrinogen gamma chains. The protein is not soluble in common E. coli lysis buffers and becomes soluble in 6 M guanidine.HCl or 6 M urea. Initial insolubility is due to interchain disulfide bond formation and to noncovalent interactions. Induced cells examined by phase-contrast microscopy contain dense inclusion bodies. A known function of the gamma chains of human fibrinogen is the clumping of Staphylococcus aureus Newman D2C cells [Hawiger et al., Biochemistry (1982) 1407-1413]. We demonstrate that suspensions of recombinant gamma chains retain the ability to clump cells from this strain of S. aureus.