Knowledge of sexual consent as a protective factor against sexual violence perpetration among first-year college men: a moderation analysis.

This study examined whether knowledge of sexual consent buffers the relationship between risk factors for sexual violence (SV) and SV perpetration among first-year college men. The study data were drawn from a longitudinal study with 1144 first-year college men. A series of generalized linear models were conducted to examine whether knowledge of sexual consent moderated the relationship between SV risk factors and SV perpetration. Knowledge of sexual consent moderated the effect of hypermasculinity (P < 0.001), binge drinking (P < 0.001), rape-supportive social norms (P = 0.007) and peer support for SV (P < 0.001) such that there was a positive association between risk factors and SV perpetration among those with lower, but not higher, knowledge of sexual consent. Knowledge of sexual consent did not significantly moderate the relationship between SV perpetration and outcome expectancies for non-consensual sex (P = 0.387) and pornography use (P = 0.494). Knowledge of sexual consent may counteract risk factors for SV perpetration among young college men. The findings highlight the need for consent education to be incorporated in youth comprehensive sexual education to increase knowledge of sexual consent prior to college and campus-based SV prevention programming delivered to college students.

Synthesis, structural characterization and Cu(ii) adsorption behavior of manganite (γ-MnOOH) nanorods.

New alternatives for the removal of transition metal ions that present an environmental risk are required. The chemical adsorption of these ions on surfaces with chemisorbent properties represents a promising area of research. In this work, manganite (γ-MnOOH) nanorods were synthesized, with a surface area of 20.22 m2 g-1, pore size of 32.18 nm and pore volume of 0.1627 cm3 g-1. After chemical and structural characterization of the manganite sample, it was evaluated as an adsorbent of Cu(ii) from aqueous solution. The equilibrium adsorption data were well fitted by the Langmuir isotherm, and the results indicated that the maximum adsorption capacity of Cu(ii) was 11.926 mg g-1. Cu(ii) ion adsorption on the manganite surface is a spontaneous and exothermic process (ΔG°< 0 and ΔH°< 0). The negative value of ΔS° suggests the stability of the adsorption process without structural change at the manganite-aqueous solution interface. A scheme for chemisorption of Cu(ii) ions on the hydroxylated surface of manganite is proposed.

Is male intent to be vaccinated against HPV a function of the promotion message?

We aimed to determine whether the type of outcome expectation, stemming from HPV vaccination, would have any effect on young men's HPV vaccine intent. We recruited young men (18-24 years of age) from two university campuses (n = 150). After answering a series of questions they were randomly assigned to one of three information conditions (all delivered by computer): (1) how women may benefit from men's HPV vaccination, (2) preventing genital warts and (3) preventing head and neck cancers. Intent to be vaccinated against HPV in the next 12 months was assessed before and after receiving the informational session corresponding to the assigned condition. A repeated-measures t-test indicated that a significant increase in young men's intent to be vaccinated after they received the assigned information (t = 9.48, [147], P = 0.0001). However, the increase in intent to be vaccinated did not vary by group assignment as there were no significant differences in mean intent scores between the three groups (F = 0.59, [2/144], P = 0.56). Information that promotes the outcome expectations of protecting women from cervical cancer, preventing genital warts for men and preventing head and neck cancers for men may be equally effective in promoting increased intent for HPV vaccine acceptance among young university men.

Predictors of condom errors among sex workers in Armenia.

This cross-sectional study identified the prevalence and correlates of condom-use errors among female sex workers (FSWs) in Armenia. One hundred and seventeen street-based FSWs aged 20-52 years completed an interviewer-administered questionnaire. Condom-use errors were reported by 78.0% of participants. Number of clients, higher frequency of condom application on clients by FSWs, greater perceived barriers to condom use, elevated depressive symptomatology and having sex while drinking alcohol were significantly associated with higher number of condom-use errors. History of sexually transmitted infections (STIs) was marginally significant while consistent condom use was not significant in the final model. The multiple regression model accounted for 32.5% of the variance in condom-use errors. Condom-use errors are prevalent in this population, thus attenuating the intended protective effects of condoms. Interventions with FSWs in Armenia should specifically address the factors identified in this study toward the goal of reducing condom errors and ultimately preventing acquisition of STIs including HIV.

Male injecting drug users in the Deep South: bisexual behaviour is a marker for elevated HIV risk.

This study determined whether bisexual male injecting drug users (IDUs) as compared with heterosexual IDUs were more likely to engage in HIV-associated risk behaviours. Respondent-driven sampling was employed to recruit a sample of 382 male IDUs residing in the southeastern USA. Data were collected in face-to-face interviews. Weighted analyses showed that bisexual IDUs in the past 12 months were 4.6 times as likely to share needles and 3.5 times as likely to share a cooker; having multiple female sexual partners and trading money or drugs for sex with women were marginally significant. Bisexual IDUs were 10 times as likely to self-report HIV. Male IDUs, who engage in bisexual behaviour, are also engaging in HIV-associated drug and to some degree sexual-risk behaviours with women more so than heterosexual IDUs. Their higher prevalence of HIV infection coupled with their risk behaviours place themselves and other IDUs at heightened risk of both acquiring and transmitting HIV.

Racial and ethnic differences in knowledge and willingness to participate in HIV vaccine trials in an urban population in the Southeastern US.

Racial/ethnic minorities in the Southeastern USA are disproportionately affected by HIV, and would benefit from a preventive vaccine. We conducted a cross-sectional survey of 220 community college students in Atlanta to evaluate racial/ethnic differences in knowledge and willingness to participate in HIV vaccine trials. Willingness to participate did not differ by race/ethnicity, age, or gender, and was not associated with knowledge. African-Americans and Asians were more likely than Whites to: believe that an HIV vaccine exists, but is being withheld from the public; believe that AIDS was caused by a government conspiracy; feel that having other participants and investigators of their ethnic background in the trial was important. Misconceptions regarding HIV vaccines are common and differ by race/ethnicity. However, willingness to participate was not associated with knowledge or race/ethnicity. Efforts to increase participation should address the ethnic diversity of the trial personnel, and education to eliminate misconceptions about HIV vaccines and trials.

Biologically confirmed sexually transmitted infection and depressive symptomatology among African-American female adolescents.

OBJECTIVE: To determine prospectively the relation between sexually transmitted infection (STI) diagnosis and depressive symptomatology. METHODS: Secondary data analyses were performed on 175 sexually active African-American female adolescents, who were recruited from high risk neighbourhoods in Birmingham, Alabama, United States. RESULTS: ANCOVA was used to compare adolescents who tested positive with adolescents who tested negative on three waves of depressive symptom scores, controlling for age. The STI positive group had higher depressive symptom levels at 6 months relative to the STI negative group. This result was moderated by baseline depressive symptom levels: for adolescents above the clinical threshold, the STI negative group experienced a decrease in symptoms at 6 months whereas the STI positive group maintained the same level. For adolescents below the clinical threshold, there were no changes in depressive symptom levels regardless of diagnosis. CONCLUSIONS: Receiving an STI diagnosis may affect depressive symptomatology for those at risk for depression. Screening for depression in settings that provide STI testing and treatment may be warranted for this population.

First Report of Beet pseudo-yellows virus and Strawberry pallidosis associated virus in Strawberry in Peru.

During a 2006 survey for the presence of criniviruses in Peru, large numbers of greenhouse whitefly (Trialeurodes vaporariorum) were observed infesting strawberry (Fragaria × ananassa) fields near Huaral on the central coast of Peru. Plants exhibited a wide range of symptoms including stunting and reddening of leaves. These symptoms are characteristic of those induced by the presence of the criniviruses Beet pseudo-yellows virus (BPYV) and/or Strawberry pallidosis associated virus (SPaV) together with any of a number of different strawberry-infecting viruses (1,3). The virus complex causes older leaves to develop a red color, vein and petiole reddening, roots become stunted, and plants fail to develop. Leaf samples with varying symptoms were collected from 22 plants from 2 fields, each planted with a different cultivar. Total nucleic acid was extracted, spotted onto positively charged nylon membranes, and tested by hybridization with probes specific to the minor coat protein (CPm) gene of BPYV (2) and coat protein (CP) gene of SPaV (4). Results identified the presence of BPYV, SPaV, or both viruses in mixed infections in symptomatic strawberry, while control plants were infected with each virus individually. No signal was detected in virus-free strawberry. Secondary confirmation was obtained using probes specific to the RNA-dependent RNA polymerase (RdRp) genes of SPaV and BPYV. The SPaV probe corresponded to nucleotides 6116-6599 of SPaV RNA1 (GenBank Accession No. NC_005895), whereas the BPYV probe corresponded to nucleotides 6076-6447 of BPYV RNA1 (GenBank Accession No. NC_005209). All probes were generated by reverse-transcription polymerase chain reaction (RT-PCR) amplification using sequence-specific primers, cloning of RT-PCR products into pGEM-T Easy (Promega, Madison, WI), confirmation by sequencing, and expression as digoxygenin-labeled transcript probes (Roche, Indianapolis, IN). Field 1, containing cv. Fern Sancho, had the largest number of symptomatic and infected plants (5 of 12 BPYV, 6 of 12 SPaV, and 4 of 12 with both). Only 1 of 10 plants from field 2 containing cv. Tajo Holandesa was infected, but with both SPaV and BPYV. BPYV and SPaV are transmitted by the greenhouse whitefly (T. vaporariorum), although BPYV is transmitted much more efficiently and has a broader host range than SPaV (4). Movement of these viruses in Peru is likely a result of both propagation by runners and vector transmission. To our knowledge, this is the first report of either virus in Peru. References: R. R Martin and I. E. Tzanetakis. Plant Dis. 90:384, 2006. (2) I. E. Tzanetakis and R. R. Martin. Plant Dis. 88:223, 2004. (3) I. E. Tzanetakis et al. Plant Dis. 87:1398, 2003. (4) I. E. Tzanetakis et al. Plant Dis. 90:1343, 2006.

Prevention and control of sexually transmitted infections among adolescents: the importance of a socio-ecological perspective--a commentary.

The sexually transmitted infection (STI) epidemic among adolescents in the USA is inextricably tied to individual, psychosocial and cultural phenomena. Reconceptualizing the epidemic within an expanded socio-ecological framework may provide an opportunity to better confront its challenges. In this article, we use a socio-ecological framework to identify determinants of adolescents' sexual risk and protective behaviours as well as antecedents of their STI acquisition. The goal is to provide a synthesis of several discrete categories of research. Subsequently, we propose an integrated strategy that addresses the STI epidemic among adolescents by promoting a socio-ecological perspective in both basic research and intervention design. This approach may expand the knowledge base and facilitate the development of a broader array of intervention strategies, such as community-level interventions, policy initiatives, institutionally based programmes, and macro-level societal changes. Although there are inherent challenges associated with such an approach, the end result may have reciprocal and reinforcing effects designed to enhance the adoption and maintenance of STI-preventive practices among adolescents, and further reduce the rate of STIs.

Lack of recent condom use among detained adolescent males: a multilevel investigation.

OBJECTIVE: To investigate multiple levels of influence with respect to the lack of recent condom use among a high risk sample of adolescent males recruited from short term detention facilities. METHODS: A cross sectional survey of 231 adolescent males serving, predominantly, short term detention sentences. Assessments were conducted using audiocomputer assisted self interviewing. Condom use during the most recent sexual event was assessed as well as 20 potential correlates of not using condoms. Correlates were assessed within five levels of causation: personal, relational, peer affiliation, family, and societal. RESULTS: Nine correlates achieved bivariate significance (p<0.05). Of these, the personal level correlates were particularly important in a multivariate model. The motivation subscale from the Condom Barriers Scale was the strongest multivariate correlate of recent condom use. Adolescents scoring below the median were about 3.4 times more likely to report lack of recent condom use (p=0.0006). Adolescents indicating they had ever caused a pregnancy were about 2.5 times more likely to report lack of condom use (p=0.02). Finally, those reporting their peers did not use condoms were about twice as likely to report lack of use (p=0.048). CONCLUSION: Upon investigating multiple levels of potential influence on condom use, the multivariate findings suggest that personal level factors may be the most important determinant of non-use among adolescent males in short term detention facilities. Although structural changes may be needed to influence some forms of safer sex behaviour, direct intervention with adolescent males may be justified to favourably alter determinants of condom use.

The association between gang involvement and sexual behaviours among detained adolescent males.

OBJECTIVE: Data were collected from 270 detained male adolescents (aged 14-18 years) to determine the association between ever having been in a gang and a range of sexual behaviours such as sexual activity, male condom use, sex with multiple partners, and drug use during sex. METHODS: Participants answered survey questions using audio computer assisted self interviewing (A-CASI) procedures, which assessed demographic, family factors, history of gang membership, and sexual behaviours. RESULTS: Multiple logistic regression analyses, controlling for demographic, socioeconomic status, and family factors, indicated that adolescents who reported having been in a gang, relative to their peers reporting no gang involvement, were 5.7 times more likely to have had sex, 3.2 times more likely to have got a girl pregnant, and almost four times more likely to have been "high" on alcohol or other drugs during sexual intercourse, have had sex with a partner who was "high" on alcohol or other drugs, or have had sex with multiple partners concurrently. CONCLUSIONS: Findings suggest that having been in a gang can discriminate between levels of STI associated risk behaviours among an otherwise high risk population-detained adolescent males.

Analysis of the RNA of Potato yellow vein virus: evidence for a tripartite genome and conserved 3'-terminal structures among members of the genus Crinivirus.

Double-stranded RNA preparations produced from potato plants graft-inoculated with a Peruvian isolate of Potato yellow vein virus (PYVV; genus Crinivirus, family Closteroviridae) contain five RNA species denoted RNA 1, RNA 2, RNA 3, x and y of approximately 8, 5.3, 3.8, 2.0 and 1.8 kbp, respectively. The complete nucleotide sequences of PYVV RNAs 1, 2 and 3 and Northern hybridization analysis showed that PYVV RNA 1 contained the replication module and an additional open reading frame (p7), while two distinct species, RNAs 2 and 3, contain the Closteroviridae hallmark gene array. Pairwise comparisons and phylogeny of genome-encoded proteins showed that PYVV shares significant homology with other criniviruses but is most closely related to the Trialeurodes vaporariorum-vectored Cucumber yellows virus. Secondary structure prediction of the 3'-untranslated regions of all three PYVV RNAs revealed four conserved stem-loop structures and a 3'-terminal pseudoknot structure, also predicted for all fully characterized members of the genus Crinivirus and some members of the genera Closterovirus and Ampelovirus.

Molecular variation of Potato yellow vein virus isolates.

To evaluate the variation of Potato yellow vein virus from potato fields, 12 isolates were collected from Colombia and one was collected from Peru. Double-stranded RNA was extracted from the plants and used as a template for RT-PCR amplification of the coat protein ( CP) gene and, in separate reactions the C-terminal region of the heat shock protein 70 homologue ( Hsp70h) gene and the N-terminal region of the p60 open reading frame. The CP amplicons were subjected to single-strand conformation polymorphism (SSCP) analysis and, together with the other amplicon, nucleotide sequence analysis. These analyses suggested that there is low genetic diversity in the PYVV isolates examined and that the Peruvian isolate of PYVV may have originated in Colombia.

Molecular resolution of a complex of potyviruses infecting solanaceous crops at the centre of origin in Peru.

Peru is a centre of origin and domestication of the potato, pepper and tomato (family Solanaceae). Many potyviruses (genus Potyvirus) that infect these crops were described 20-30 years ago. However, definitive classification of these viruses as distinct species remains unresolved for several reasons, including their close serological relationships, similar symptomatology in test plants and lack of genomic sequence data. Using samples collected from Peru, we have determined the complete genomic sequence of two strains of Peru tomato virus (PTV) as well as near-complete sequences for two additional PTV strains. We also obtained partial sequences of four strains of Potato virus V (PVV). Comparisons with genomic sequences of Wild potato mosaic virus (WPMV), Potato virus Y (PVY), Pepper mottle virus (PepMoV), Potato virus A (PVA) and other potyviruses established that all these viruses constitute different taxa (species). Phylogenetic comparisons indicated that PTV, PVV and WPMV are the most closely related species which, together with PepMoV, PVY, Pepper yellow mosaic virus and Pepper severe mosaic virus, constitute a group that is distinguishable from other potyviruses. Therefore, the members of this group may share a common ancestor. PVA does not belong to this group. PVV and PTV were also closely related serologically. However, PTV did not cross-protect against PVV and WPMV in tobacco plants or complement systemic infection of PVV and WPMV in pepper plants. Two biologically and phylogenetically distinguishable strain groups were identified within PTV and PVV. In future studies, the sequence data and virus-specific primers and probes for PTV, PVV and WPMV described in this study will enable accurate indexing of plants with respect to either single or mixed infection with these viruses.

First Report of Sweet potato leaf curl virus in Peru.

Leaf curling symptoms have been reported in sweet potato (Ipomoea batatas) plants infected with a geminivirus (1). Leaf curl disease appeared in Peru after the 1997 to 1998 El Niño, when the population and activity of whiteflies (Bemisia tabaci, B. argentifolii, and B. afer) increased. Approximately 6% of plants in farmers' commercial fields in San Ramón, Junín (September 2000) and Cañete, Lima (February 2001) showed typical leaf curling symptoms. Seventeen plants in total were collected from both places, and stem scions from those plants were graft-inoculated to I. setosa, which developed symptoms of leaf curling, interveinal chlorosis, and stunting. Total nucleic acid was obtained from infected sweet potato and I. setosa plants using cetyltrimethylammoniumbromide (CTAB) extraction, and primers PW285-3 (5'-CGT CGT TAG CAG TCT GCA GGC CTC CTC TAG-3') and PW285-4 (5' -AAC TGT AAA TAC GGA ACT GCA GTT CGA ATT-3') for Sweet potato leaf curl virus (SPLCV), developed and provided by R. Valverde and C. Clark of Louisiana State University (2), were used to amplify SPLCV by polymerase chain reaction (PCR). Expected DNA fragments of ca. 900 bp (in all samples) and 2.4 kp (in some samples), characteristic of the subgenomic and genomic DNAs of SPLCV respectively, were obtained from symptomatic but not from symptomless (uninfected) plants. This 2.4-kb fragment was amplified in relatively small amounts compared to the 900-bp fragment. Presence of SPLCV was also confirmed by nucleic acid spot hybridization using a full-length clone of SPLCV-US. Fourteen of 17 plants infected with SPLCV were also infected with Sweet potato chlorotic stunt virus (determined by nitrocellulose membrane enzyme-linked immunosorbent assay serological test), which is also transmitted by whiteflies. These viruses now seem to be common in farmers' fields in San Ramón and Cañete. To our knowledge, this is the first report of SPLCV in Peru. References: (1) P. Lotrakul et al. Plant Dis. 82:1253, 1998. (2) P. Lotrakul and R. A. Valverde. Cloning of a DNA-A like genomic component of sweet potato leaf curl virus: nucleotide sequence and phylogenetic relationships. Molecular Plant Pathology On-Line ( http://www.bspp.org.uk/mppol/1999/0422lotrakul/paper.htm ), 1999.

Sweetpotato Virus Disease (SPVD): Distribution, Incidence, and Effect on Sweetpotato Yield in Peru.

Sweetpotato virus disease (SPVD), the most important disease affecting sweetpotato (Ipomoea batatas (L.) Lam), is caused by the synergistic interaction of the aphid-transmitted Sweetpotato feathery mottle virus (SPFMV) and whitefly-transmitted Sweetpotato chlorotic stunt virus (SPCSV). In this study, SPVD was the main disease in the Cañete Valley, the major sweetpotato-producing area in Peru. Studies on virus incidence showed that SPCSV and SPFMV were the most frequently identified viruses in Cañete Valley. Symptoms of different severity were associated with isolates of both viruses involved in the SPVD. Over 80% of plants infected with both SPFMV and SPCSV showed the symptoms (leaf reduction and deformation, vein clearing or mosaic, and stunting) typically attributed to SPVD elsewhere. SPFMV did not significantly affect the yield of the sweetpotato cultivars Jonathan and Costanero, but infection of these cultivars by SPCSV was associated with significant yield reduction. Double infection by the two viruses resulted in SPVD and greater yield reduction than for either alone. These results demonstrate that SPFMV and SPCSV interact synergistically and that the severity of SPVD symptoms also depends on the particular isolate of each virus.

Other Natural Hosts of Potato virus T.

Potato virus T (PVT), a member of the genus Trichovirus, was isolated from leaves of naturally infected ulluco (Ullucus tuberosus), oca (Oxalis tuberosa), and mashua (Tropaeolum tuberosum). These Andean tuber crops are often grown in small plots in association with potato (Solanum tuberosum) in the Peruvian highlands. PVT isolates from ulluco, oca, mashua, and potato infected virus-free ulluco, oca, and potato genotypes by mechanical inoculation. The incidence of PVT in mashua, oca, and ulluco accessions from the International Potato Center (CIP) in vitro germplasm bank was less than 10%. A polymerase chain reaction (PCR) product of approximately 330 bp was obtained from each of the four isolates using primers designed from the published PVT sequence. Restriction enzyme digestions of the PCR product did not demonstrate variability.

Etiology of Sweet Potato Chlorotic Dwarf Disease in Argentina.

Chlorotic dwarf (CD), the most important disease in the sweet potato-producing regions of Argentina, is caused by the synergistic combination of two aphid-transmitted potyviruses with a whitefly-transmitted crinivirus. Sweet potato feathery mottle virus, sweet potato mild speckling virus, and a crinivirus (serologically related to sweet potato chlorotic stunt virus) were associated with CD. The synergistic combination of these three viruses reproduced the disease.

Evidence for heterologous encapsidation of potato spindle tuber viroid in particles of potato leafroll virus.

The aphid Myzus persicae (Sulz.) was shown to transmit potato spindle tuber viroid (PSTVd) to potato clone DTO-33 from source plants doubly infected with potato leafroll virus (PLRV) and PSTVd. Transmission was of the persistent type and did not occur when the insects were allowed to feed on singly infected plants. Only low levels of PSTVd were associated with purified PLRV virions, but its resistance to digestion with micrococcal nuclease indicates that the viroid RNA is encapsidated within the PLRV particles. Epidemiological surveys carried out at three locations in China revealed a strong correlation between PSTVd infection and the presence of PLRV, suggesting that PLRV can facilitate PSTVd spread under field conditions.