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PubMed2005

Epidemiology of HIV/AIDS among Asians and Pacific Islanders in the United States.

Although the percentage of overall AIDS diagnoses remains low among Asian and Pacific Islanders (APIs) in the United States compared with other racial/ethnic groups, research on API risk behaviors and health status suggest that the low number of AIDS cases may not provide a full picture of the epidemic and issues faced by this understudied and underserved population. Data from national HIV/AIDS surveillance systems and the Behavioral Risk Factor Surveillance System (BRFSS) were examined to delineate the magnitude and course of the HIV/AIDS epidemic among APIs in the United States. Same-sex sexual activity is the main HIV risk for API men, whereas heterosexual contact is for API women. APIs are significantly less likely to report being tested for HIV despite the fact that a similar proportion of APIs and other racial/ethnic groups reported having HIV risk in the past 12 months. Given the enormous diversity among APIs in the United States it is important to collect detailed demographic information to improve race/ethnicity and HIV risk classification, conduct better behavioral and disease monitoring for informing prevention planning, and addressing cultural, linguistic, economic and legal barriers to HIV prevention among APIs.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Lack of direct action of atriopeptidase inhibitor on cellular pH regulation in rabbit S2 proximal straight tubules.

While the in vivo diuretic and antihypertensive effects of the newly-developed drug Candoxatril (UK-79300), a prodrug of a selective atriopeptidase inhibitor UK-73967 (API) are well established, the mechanism of its diuretic action is not yet fully understood due to the lack of information about its direct effects on proximal tubules. To elucidate whether this atriopeptidase inhibitor has any direct effects on proximal tubules, we examined the effect of API on intracellular pH (pHi) of the in vitro microperfused proximal S2 segment of rabbit kidney, using the pH-sensitive fluorescent dye, (2',7')-bis(carboxyethyl)-(5,6)-carboxyfluorescein (BCECF). In the steady-state condition, pHi was 7.13 +/- 0.02 (n = 19). Atriopeptidase inhibitor (API) at 100 microM added to the bath changed pHi by only 0.02 +/- 0.07 unit (n = 7, p > 0.05) in 10 min. The same concentration of API in the lumen changed pHi by 0.03 +/- 0.02 unit (n = 6, p > 0.05). To test whether the synergistic effects of API on the luminal and basolateral transport systems prevented the apparent change in pHi, we also examined the effect of API in the presence of amiloride in the lumen. The inhibition of Na+/H+ antiporter by the addition of 1 mM of amiloride to the lumen caused no change in pHi response to basolateral API application. API was without effect on pHi also in the presence of atrial natriuretic polypeptide (ANP). These results suggest that API per se has no significant effect on the process of proximal acidification over a short time period.

Animals↗
PubMed1993

[The relative assessment of atherosclerosis in vessels of major organs and its factors for progression].

In order to study the relative assessment of atherosclerosis among arteries of various organ (coronary, aortic, peripheral and cerebral artery), 94 patients aged 43-69 underwent examination by coronary angiography (CAG), pulse wave velocity (PWV), ankle pressure index (API) and funduscopy simultaneously. The severity of coronary sclerosis was determined by the coronary atherosclerotic index (CAI) which was based on the size and number of stenotic lesions, which that of funduscopic findings was evaluated using Scheies' score (S+H). The relationship between risk factors of atherosclerosis and each value for the examinations (CAI, PWV, API, S+H) were studied. Furthermore, subjects were divided into two groups of normal or early change groups and a progressive group based on the degree of atherosclerosis. Then, the difference of atherosclerosis in each vessel of major organs was compared. A positive correlation between PWV and age, and a negative correlation between API and age were noted (p < 0.01, p < 0.05). A higher prevalence of hypertension in groups of progressive PWV or API were observed (p < 0.05). Total cholesterol in the CAI progressive group was significantly higher than in the normal group (p < 0.005), and it became higher in relation to the progression of PWV or API (p < 0.001). HDL-C in the progressive groups of CAI, PWV API and S+H were significantly lower (p < 0.05, p < 0.05, p < 0.02, p < 0.01). On the other hand, glucose intolerance influenced the progression of CAI, PWV, API and S+H, statistically. In subjects whose age was limited to between 55-64, statistically significant correlations were noted between any pair of examinations among CAI, PWV, API and S+H. The percentage of API and S+H progressive groups were lower in CAI normal of PWV early change groups, suggesting earlier sclerotic change of the coronary artery or aorta than that of peripheral or cerebral artery. These results demonstrate that the atherosclerosis in major vessels could be assessed relatively using a non pathological process, which supports the usefulness of these examinations in clinical practice.

Adult↗
PubMed2000

Hepatitis B vaccination coverage among Asian and Pacific Islander children--United States, 1998.

Asian and Pacific Islander (API) children in the United States have high rates of hepatitis B virus (HBV) infection (1-3). To prevent these infections, hepatitis B vaccination has been recommended for these children since the vaccine was first licensed by the Food and Drug Administration in 1981 (4). Recommendations have included universal hepatitis B vaccination of API infants beginning in 1990 and catch-up vaccination for API children aged <7 years (5). These recommendations were reinforced in 1991 when hepatitis B vaccination was recommended for all infants, particularly in populations such as API children with high rates of early childhood HBV infection (6). In 1995, vaccination was recommended for unvaccinated API children aged <11 years and catch-up vaccination for children aged 11-12 years who had not received hepatitis B vaccine (HepB) (7). Series completion among API children aged 19-35 months increased from 39% in 1994 to 88% in 1997 (8). However, among older API children, hepatitis B vaccination coverage was 10% in 1995 (7). In 1998, to examine trends in hepatitis B vaccination catch-up coverage among API children born before 1994, surveys were conducted in six U.S. cities. This report summarizes the results of the surveys, which indicate varying coverage among API children and suggest a need for continued focused vaccination programs for this population.

Asian↗
PubMedDate not supplied

Vaccinating Asian Pacific Islander children against hepatitis B: ethnic-specific influences and barriers.

PURPOSE: Hepatitis B virus (HBV) is a known cause of liver cancer, especially among Asian and Pacific Islanders (API). Despite national recommendations and school entry requirements for vaccination, many children are not fully vaccinated with the Hepatitis B vaccine (Hep B) before entering school. The purpose of this study was to measure ethnic group-specific hepatitis B vaccination rates among school-aged API children after implementation of universal recommendations and school laws, and quantify ethnic-specific risk factors associated with late and incomplete vaccinations. METHODS: A multilingual questionnaire was distributed to parents of second and fourth graders in nine Los Angeles County (LAC) elementary schools with high proportions of API students. Data on Hepatitis B vaccination dates, source of health care and health information, cultural factors, and general knowledge and attitudes about HBV and vaccination were collected and analyzed. FINDINGS: Overall, 1,696 (77%) of 2,183 questionnaires were returned. Of these, 1,024 were from API children. The API second graders in this survey had a 72% coverage rate, ranging from 46% to 94% among the individual ethnic groups. Fifty-one percent of API fourth graders had three doses of Hep B vaccine, ranging from 38% to 69% among the individual ethnic groups. Factors influencing coverage levels among API fourth graders were speaking limited English at home, living in the United States less than five years, and not having discussed hepatitis B vaccination with a health care provider. Factors influencing low immunization levels differed among the API ethnic groups. CONCLUSIONS: Analysis and intervention on a non-aggregate level are necessary for designing both effective and cultural-specific outreach programs for diverse API communities such as LAC's.

Asian↗
PubMed2005

HIV risks and testing behavior among Asians and Pacific Islanders: results of the HIV Testing Survey, 2002-2003.

INTRODUCTION: The HIV Testing Survey (HITS) was developed to examine HIV testing and risk behavior in individuals at risk for HIV infection. The first Seattle HITS was conducted in 2000 (HITS-2000); HITS was conducted in Seattle again in 2002-2003 among Asians and Pacific Islanders (HITS-API). METHODS: Both HITS projects, HITS-API and HITS-2000, included anonymously targeted participants from at-risk populations. Data from the surveys were compared to see whether there were differences in HIV testing behavior between API and a general at-risk population in the Seattle area. Data were analyzed for 165 participants in HITS-API and 270 in HITS-2000. RESULTS: More API (90%) perceived themselves at some HIV risk relative to HITS-2000 participants (71%, chi2 p<0.05). In HITS-API and HITS-2000, participants reported significant HIV risks--no or inconsistent condom use with nonprimary partners or sharing injection equipment. Only 47% of HITS-API participants tested in the past year compared with 64% of HITS-2000. There was no association between HIV testing and risks in HITS-API. CONCLUSIONS: Based on self-report from HITS-API, the overall perceived risk for HIV infection was high, many engaged in high-risk behaviors, and HIV testing was suboptimal.

AIDS Serodiagnosis↗
PubMed1987

Immunohistochemical demonstration of alpha-1-proteinase inhibitor in brain tumors.

Using light microscopy and immunoperoxidase methods (PAP), the presence of alpha-1-proteinase inhibitor (API) was studied in seventeen brain tumors and four normal brain samples. The brain tumors included four glioblastomas, five low-grade gliomas, two metastatic lung carcinomas, two acoustic schwannomas, and four meningiomas. Normal brain displayed a finely granular intracytoplasmic staining confined to neuronal cells. Glial cells were negative for API. Fifteen of the 17 brain tumors were positive for API. Only two of five low-grade gliomas were negative for API. Glioblastoma and metastatic tumors exhibited the strongest positivity followed by acoustic neuroma, meningioma, and low-grade glioma. All positive samples exhibited finely granular intracytoplasmic API, and 50% exhibited extracellular API positivity. Metastatic and glioblastoma tumors demonstrated prominent extracellular API staining. Our results support the concept of a local production of API by brain tumors.

Blood Proteins↗
PubMed2001

Novel bifunctional alkaline protease inhibitor: protease inhibitory activity as the biochemical basis of antifungal activity.

An alkaline protease inhibitor (API) from a Streptomyces sp. NCIM 5127 was shown to possess antifungal activity against several phytopathogenic fungi besides its antiproteolytic (anti-feedent) activity [J. V. Vernekar et al. (1999) Biochem. Biophys. Res. Commun. 262, 702-707]. Based on the correlation between antiproteolytic and antifungal activities in several tests such as copurification, heat inactivation, chemical modification, and its binding interaction with the fungal protease, we demonstrate, for the first time, that the dual function of API is a consequence of its ability to inhibit the essential alkaline protease. The parallel enrichment of both the functions during purification together with the heat inactivation of API leading to the concomitant loss of the two activities suggested their presence on a single molecule. Chemical modification of API with NBS resulted in the complete loss of antiproteolytic and antifungal activities, with no gross change in conformation implying the involvement of a Trp residue in the active site of the inhibitor and the presence of a single active site for the two activities. Treatment of API with DTT abolished both the activities although the native structure of API remained virtually unaffected, indicating the catalytic role of the disulfide bonds. Inactivation of API either by active site modification or by conformational changes leads to the concurrent loss of both the antiproteolytic and antifungal activities. Experimental evidences presented here serve to implicate that the antifungal activity of API is a consequence of its protease inhibitory activity.

Amino Acids↗
PubMed2005

Deliquescence in binary mixtures.

PURPOSE: Deliquescence is a first-order phase transformation from solid to solution and occurs at a specific relative humidity (RH) that is characteristic to the solid. The goal of this research was to investigate the reduction in critical relative humidity (RH0) in binary solid mixtures of deliquescent active pharmaceutical ingredients (APIs) and deliquescent excipients. METHODS: The RH where deliquescence is induced, RH0, was measured using a gravimetric water vapor sorption balance. Values were obtained for model deliquescent APIs and excipients as well as for their binary mixtures. Model APIs included ranitidine HCl and diphenhydramine HCI, and sucrose and sodium chloride were examples of excipients investigated. To probe the thermodynamics of this phenomenon, water activity (a(w)) of various saturated solutions of API and excipient systems was measured using a water activity meter. Optical microscopy was used to observe visually the phenomenon under investigation. The Ross equation was used to estimate RH0mix, and predicted values were compared with experimental results. RESULTS: There was close agreement between RH0 measurements (single-component RH0, and RH0mix) and a(w) measurements of the corresponding saturated solutions. In addition, RH0mix values were always lower than RH0 for the API and excipients alone. In general, experimentally observed RH0mix values were higher than those predicted using the Ross equation. CONCLUSIONS: Mixtures of deliquescent API and deliquescent excipient are more hygroscopic (i.e., have lower RH0) than either the API or the excipient alone. This might have significant effects on API and drug product stability.

Humidity↗
PubMed1995

Decreased branching, increased fucosylation and changed sialylation of alpha-1-proteinase inhibitor in breast and ovarian cancer.

Proteolytic enzymes could be very important in spread of cancer, but the role of the body's natural inhibitors of these enzymes in this process is unknown. One such inhibitor is the serum glycoprotein, alpha-1-proteinase inhibitor (API). In previous studies we showed that the fucose-specific lectin, lotus tetragonolobus, extracted high amounts of API in cancer when patients were unresponsive to treatment. The aim of this study was to determine whether the carbohydrate structure of API is altered in cancer. API was isolated from the sera of healthy women and women with breast or ovarian cancer. By means of high-performance anion-exchange chromatography, cancer API was shown to contain more fucose and less N-acetylglucosamine than healthy API. Further investigation of the purified specimens using a lectin-binding assay suggested that the cancer API was less branched and contained more alpha 2-6 and less alpha 2-3 sialic acid. Observations from both methods were consistent with an increase in bi-antennary chains terminating in alpha 2-6 sialic acid and possibly more alpha 1-6 fucose in the core of the unit. These distinctive changes could have important consequences for the function of API in cancer and may help to develop more precise markers for monitoring pathological progression in this disease.

Adenocarcinoma, Mucinous↗
PubMed2005

Examining the out-of-center distortion in the [NbOF5]2- anion.

Out-of-center "primary" electronic distortions are inherent to the oxide fluoride anions of the early d0 transition metals. In the [NbOF5]2- anion, the Nb5+ moves from the center of the octahedron toward the oxide ligand to form a short Nb=O bond and long trans Nb-F bond. The combined results of single-crystal X-ray diffraction and electronic structure calculations indicate that the primary distortion of the [NbOF5]2- anion is affected by the coordination environment that is created by the three-dimensional extended structure. The formation of bonds between an M(L)4(2+) (M = Cd2+, Cu2+; L = 3-aminopyridine, 4-aminopyridine) cation and the oxide and/or trans-fluoride ligands of the [NbOF5]2- anion weakens the pi component of the Nb=O bond. At the same time, hydrogen bond interactions between the equatorial fluorides and the aminopyridine groups both lengthen the equatorial Nb-F bonds and can further reduce the symmetry of the [NbOF5]2- anion. These combined three-dimensional bond network interactions that serve to lengthen the Nb=O bond and thereby decrease the primary distortion of the [NbOF5]2- anion are illustrated in the structures of three new niobium oxide fluoride phases, [4-apyH]2[Cu(4-apy)4(NbOF5)2] (4-apy = 4-aminopyridine), Cd(3-apy)4NbOF5 (3-apy = 3-aminopyridine), and Cu(3-apy)4NbOF5, that were synthesized and characterized using X-ray diffraction. Crystal data for [4-apyH]2[Cu(4-apy)4(NbOF5)2]: tetragonal, space group /4(1)/ acd (No. 142), with a = 20.8745(8) A, c = 17.2929(9) A, and Z= 8. Cd(3-apy)4NbOF5: tetragonal, space group P4(3) (No. 78), with a = 8.4034(4) A, c = 34.933(3) A, and Z = 4. Cu(3-apy)4NbOF5: monoclinic, space group P2(1)/n (No. 14), with a = 8.822(1) A, b = 16.385(3) A, c = 8.902(1) A, beta = 109.270(3) degrees, and Z = 2.

Journal Article↗
PubMedDate not supplied

Cervical intraepithelial lesions and cervical cancer among Asian Pacific Islander women in a cervical cancer screening program.

Utilizing data from a cervical cancer screening program in California, we examined the relationship between being a woman of Asian/Pacific Islander (API) origin and receiving different types of abnormal cervical diagnoses. Initial descriptive data reflected a higher than expected percentage of API subjects with a final diagnosis of in situ and invasive cervical cancer when compared with other subjects in other ethnic groups (N = 2792). Results of multivariate analysis indicated that being of API origin retained significance in a model explaining the level of severity of the cervical final diagnosis, even when controlling for other significant predictors such as having a prior pap smear, age, referral source, the presence of cervical abnormalities and the time from screening to diagnosis. We conclude that women of API origin may not be accessing health care sufficiently early to prevent increasingly severe final diagnoses. Utilizing data from a cervical cancer screening program in California, we examined the relationship between being a woman of Asian/Pacific Islander (API) origin and receiving different types of abnormal cervical diagnoses. Initial descriptive data reflected a higher than expected percentage of API subjects with a final diagnosis of in situ and invasive cervical cancer when compared with other subjects in other ethnic groups (N = 2792). Results of multivariate analysis indicated that being of API origin retained significance in a model explaining the level of severity of the cervical final diagnosis, even when controlling for other significant predictors such as having a prior pap smear, age, referral source, the presence of cervical abnormalities and the time from screening to diagnosis. We conclude that women of API origin may not be accessing health care sufficiently early to prevent increasingly severe final diagnoses.

Adult↗
PubMed1992

Aminopeptidase I of Saccharomyces cerevisiae is localized to the vacuole independent of the secretory pathway.

The Saccharomyces cerevisiae APE1 gene product, aminopeptidase I (API), is a soluble hydrolase that has been shown to be localized to the vacuole. API lacks a standard signal sequence and contains an unusual amino-terminal propeptide. We have examined the biosynthesis of API in order to elucidate the mechanism of its delivery to the vacuole. API is synthesized as an inactive precursor that is matured in a PEP4-dependent manner. The half-time for processing is approximately 45 min. The API precursor remains in the cytoplasm after synthesis and does not enter the secretory pathway. The precursor does not receive glycosyl modifications, and removal of its propeptide occurs in a sec-independent manner. Neither the precursor nor mature form of API are secreted into the extracellular fraction in vps mutants or upon overproduction, two additional characteristics of soluble vacuolar proteins that transit through the secretory pathway. Overproduction of API results in both an increase in the half-time of processing and the stable accumulation of precursor protein. These results suggest that API enters the vacuole by a posttranslational process not used by most previously studied resident vacuolar proteins and will be a useful model protein to analyze this alternative mechanism of vacuolar localization.

Aminopeptidases↗
PubMed1995

Isolation and characterization of yeast mutants in the cytoplasm to vacuole protein targeting pathway.

In Saccharomyces cerevisiae the vacuolar protein aminopeptidase I (API) is localized to the vacuole independent of the secretory pathway. The alternate targeting mechanism used by this protein has not been characterized. API is synthesized as a 61-kD soluble cytosolic precursor. Upon delivery to the vacuole, the amino-terminal propeptide is removed by proteinase B (PrB) to yield the mature 50-kD hydrolase. We exploited this delivery-dependent maturation event in a mutant screen to identify genes whose products are involved in API targeting. Using antiserum to the API propeptide, we isolated mutants that accumulate precursor API. These mutants, designated cvt, fall into eight complementation groups, five of which define novel genes. These five complementation groups exhibit a specific defect in maturation of API, but do not have a significant effect on vacuolar protein targeting through the secretory pathway. Localization studies show that precursor API accumulates outside of the vacuole in all five groups, indicating that they are blocked in API targeting and/or translocation. Future analysis of these gene products will provide information about the subcellular components involved in this alternate mechanism of vacuolar protein localization.

Alleles↗
PubMed2004

Both chaperone and isomerase functions of protein disulfide isomerase are essential for acceleration of the oxidative refolding and reactivation of dimeric alkaline protease inhibitor.

Oxidative refolding of the dimeric alkaline protease inhibitor (API) from Streptomyces sp. NCIM 5127 has been investigated. We demonstrate here that both isomerase and chaperone functions of the protein folding catalyst, protein disulfide isomerase (PDI), are essential for efficient refolding of denatured-reduced API (dr-API). Although the role of PDI as an isomerase and a chaperone has been reported for a few monomeric proteins, its role as a foldase in refolding of oligomeric proteins has not been demonstrated hitherto. Spontaneous refolding and reactivation of dr-API in redox buffer resulted in 45% to 50% reactivation. At concentrations <0.25 microM, reactivation rates and yields of dr-API are accelerated by catalytic amounts of PDI through its isomerase activity, which promotes disulfide bond formation and rearrangement. dr-API is susceptible to aggregation at concentrations >25 microM, and a large molar excess of PDI is required to enhance reactivation yields. PDI functions as a chaperone by suppressing aggregation and maintains the partially unfolded monomers in a folding-competent state, thereby assisting dimerization. Simultaneously, isomerase function of PDI brings about regeneration of native disulfides. 5-Iodoacetamidofluorescein-labeled PDI devoid of isomerase activity failed to enhance the reactivation of dr-API despite its intact chaperone activity. Our results on the requirement of a stoichiometric excess of PDI and of presence of PDI in redox buffer right from the initiation of refolding corroborate that both the functions of PDI are essential for efficient reassociation, refolding, and reactivation of dr-API.

Bacterial Proteins↗
PubMed2005

Efficacy of the Cybersonic in comparison with the Braun 3D Excel and a manual toothbrush.

OBJECTIVES: To evaluate the efficacy of two power toothbrushes (Cybersonic and Braun 3D Excel) and one manual brush (Elmex super 29). MATERIAL AND METHODS: After professional toothcleaning 120 subjects were randomly assigned to three groups. Four weeks later, at baseline, the Quigley-Hein plaque index (QHI), the modified approximal plaque index (API), and the papillary bleeding index (PBI) were recorded. Thereafter the subjects used the assigned toothbrushes for 8 weeks. Improvements of the indices after 4 and 8 weeks were calculated as medians. Kruskal-Wallis- and Mann-Whitney U-test served for statistical analysis. RESULTS: All indices showed statistically significant reductions for both power toothbrushes which were superior to the manual brush (4 weeks: Cybersonic: API, 0.21; PBI, 0.25; QHI, 0.23; Braun: API, 0.20; PBI, 0.39; QHI, 0.22; Elmex: API, 0.04; PBI, 0.02; QHI, 0.07; 8 weeks: Cybersonic: API, 0.28; PBI, 0.36; QHI, 0.41; Braun: API, 0.36; PBI, 0.61; QHI, 0.35; Elmex: API, 0.03; PBI, 0.10; QHI, 0.08; p<0.001). The Braun was superior to the Cybersonic with respect to API after 8 weeks (p<0.05) and PBI after 4 and 8 weeks (p<0.01). CONCLUSION: Cybersonic and Braun 3D Excel may be more efficacious than a manual toothbrush in removing plaque and reducing gingivitis.

Adolescent↗
PubMed1995

Evaluation of the AUXACOLOR system, a new method of clinical yeast identification.

AIMS: To compare the AUXACOLOR yeast identification system with the API 20C system. METHODS: Yeast isolates (n = 215), comprising 16 species, were identified using the AUXACOLOR system and the API 20C system. Isolates that could not be identified with the API 20C system or which produced discrepant results in the two systems were identified by assimilation and fermentation procedures. RESULTS: AUXACOLOR correctly identified 150 (85.7%) of 175 germ tube negative isolates while API 20C identified 155 (88.6%). Incorrect identifications were more common with API 20C (7.4%) than with AUXACOLOR (3.7%). Of 110 isolates of four common pathogens (Candida glabrata, C parapsilosis, C tropicalis, and Cryptococcus neoformans), 82.7% (91/110) were identified by AUXACOLOR while API 20C identified 74.5% (82/110). Of 65 less common germ tube negative isolates, 55.4% (36/65) were identified by AUXACOLOR while API 20C identified 63.1% (41/65). CONCLUSION: Although it has a limited database of 26 species, the AUXACOLOR system is a useful method for identification of germ tube negative clinical yeast isolates. Compared with the API 20C, the AUXACOLOR system is simpler and quicker to set up, easier to interpret, and comparable in cost.

Candida↗
PubMed2003

Age and race mixing patterns of sexual partnerships among Asian men who have sex with men: implications for HIV transmission and prevention.

Recent studies of U.S. men who have sex with men (MSM) have reported high rates of unprotected anal intercourse but low rates of HIV infection among Asian and Pacific Islander (API) men. We investigated this discrepancy by examining the characteristics of sexual partnerships among API MSM. Multivariate logistic regression analyses found that having an API partner was related to having unprotected anal intercourse after controlling for respondent's age, number of sexual partners, and partner type. Having an API partner and a younger partner were related to respondent reports of unprotected insertive anal intercourse. However, a partner's race and age did not predict unprotected receptive anal intercourse. Study findings suggest that HIV prevalence among API MSM may have remained relatively low because higher risk sexual practices occur more frequently within a lower risk API group compared with higher risk non-API groups. However, because the possibility for the rise of HV infection in this population still exists if HIV spreads from older to younger men, HIV prevention efforts must target partner characteristics to maintain low HIV prevalence among API MSM.

Adult↗