Field test of quantum key distribution in the Tokyo QKD Network.

A secure communication network with quantum key distribution in a metropolitan area is reported. Six different QKD systems are integrated into a mesh-type network. GHz-clocked QKD links enable us to demonstrate the world-first secure TV conferencing over a distance of 45km. The network includes a commercial QKD product for long-term stable operation, and application interface to secure mobile phones. Detection of an eavesdropper, rerouting into a secure path, and key relay via trusted nodes are demonstrated in this network.

Coinfection with hepatitis C virus, oxidative stress and antioxidant status in HIV-positive drug users in Miami.

BACKGROUND: The pathogenesis of HIV/hepatitis C virus (HCV) coinfection is poorly understood. We examined markers of oxidative stress, plasma antioxidants and liver disease in HIV/HCV-coinfected and HIV-monoinfected adults. METHODS: Demographics, medical history, and proof of infection with HIV, hepatitis A virus (HAV), hepatitis B virus (HBV) and HCV were obtained. HIV viral load, CD4 cell count, complete blood count (CBC), complete metabolic panel, lipid profile, and plasma concentrations of zinc, selenium, and vitamins A and E were determined. Malondialdehyde (MDA) and glutathione peroxidase concentrations were obtained as measures of oxidative stress. Aminotransferase to platelet ratio index (APRI) and fibrosis index (FIB-4) markers were calculated. RESULTS: Significant differences were found between HIV/HCV-coinfected and HIV-monoinfected participants in levels of alanine aminotransferase (ALT) (mean±standard deviation: 51.4±50.6 vs. 31.9±43.1 U/L, respectively; P=0.014), aspartate aminotransferase (AST) (56.2±40.9 vs. 34.4±30.2 U/L; P<0.001), APRI (0.52±0.37 vs. 0.255±0.145; P=0.0001), FIB-4 (1.64±.0.91 vs. 1.03±0.11; P=0.0015) and plasma albumin (3.74±0.65 vs. 3.94±0.52 g/dL; P=0.038). There were no significant differences in CD4 cell count, HIV viral load or antiretroviral therapy (ART) between groups. Mean MDA was significantly higher (1.897±0.835 vs. 1.344± 0.223 nmol/mL, respectively; P=0.006) and plasma antioxidant concentrations were significantly lower [vitamin A, 39.5 ± 14.1 vs. 52.4±16.2 µg/dL, respectively (P=0.0004); vitamin E, 8.29±2.1 vs. 9.89±4.5 µg/mL (P=0.043); zinc, 0.61±0.14 vs. 0.67±0.15 mg/L (P=0.016)] in the HIV/HCV-coinfected participants than in the HIV-monoinfected participants, and these differences remained significant after adjusting for age, gender, CD4 cell count, HIV viral load, injecting drug use and race. There were no significant differences in glutathione peroxidase concentration, selenium concentration, body mass index (BMI), alcohol use or tobacco use between groups. Glutathione peroxidase concentration significantly increased as liver disease advanced, as measured by APRI (ß=0.00118; P=0.0082) and FIB-4 (ß=0.0029; P=0.0177). Vitamin A concentration significantly decreased (ß=-0.00581; P=0.0417) as APRI increased. CONCLUSION: HIV/HCV coinfection is associated with increased oxidative stress and decreased plasma antioxidant concentrations compared with HIV monoinfection. Research is needed to determine whether antioxidant supplementation delays liver disease in HIV/HCV coinfection.

C-reactive protein: a poor marker of cardiovascular disease risk in HIV+ populations with a high prevalence of elevated serum transaminases.

Blood lipids and high-sensitivity C-reactive protein (hsCRP) are used to assess cardiovascular disease (CVD) risk. We evaluated in a cross-sectional design the relationship of hsCRP to markers of liver function (aspartate and alanine transaminases [AST and ALT, respectively]), CVD risk factors and HIV-disease progression markers in 226 HIV-1 sero-positive drug users. hsCRP showed a significant inverse relationship with ALT and high-density lipoprotein, independent of age, gender, viral load, CD4 cell-count and antiretroviral (ARV) use, and was not significantly associated with HIV-disease progression markers. Serum markers of liver damage, AST and ALT, were associated with lower hsCRP, total cholesterol, low-density lipoproteins and triglycerides. Elevated liver enzymes (> or =40 IU/L) were predictive of hsCRP levels that are considered a low risk for CVD. In conclusion, hsCRP may not be a reliable marker of CVD risk in populations with HIV at-risk for elevated liver enzymes due to high hepatitis B virus/hepatitis C virus prevalence and ARV use.

Breathers in Josephson junction ladders: resonances and electromagnetic wave spectroscopy.

We present a theoretical study of the resonant interaction between dynamical localized states (discrete breathers) and linear electromagnetic excitations (EE's) in Josephson junction ladders. By making use of direct numerical simulations we find that such an interaction manifests itself by resonant steps and various sharp switchings (voltage jumps) in the current-voltage characteristics. Moreover, the power of ac oscillations away from the breather center (the breather tail) displays singularities as the externally applied dc bias decreases. All these features may be mapped to the spectrum of EE's that has been derived analytically and numerically. Using an improved analysis of the breather tail, a spectroscopy of the EE's is developed. The nature of breather instability driven by localized EE's is established.

Penetration of dynamic localized states in dc-driven Josephson junction ladders by discrete jumps.

We give a theoretical study of unusual resistive (dynamic) localized states in anisotropic Josephson junction ladders, driven by a dc current at one edge. These states comprise nonlinearly coupled rotating Josephson phases in adjacent cells, and with increasing current they are found to expand into neighboring cells by a sequence of sudden jumps. We argue that the jumps arise from instabilities in the ladder's superconducting part, and our analytic expressions for the peculiar voltage (rotational frequency) ratios and I-V curves are in very good agreement with direct numerical simulations.

High-risk behaviours in men from Bogotá, Colombia and the spread of HIV.

Our objective was to identify sexual behaviours related to risk of HIV infection. A cluster survey of sexually experienced men from diverse sociodemographic settings in Bogotá, Colombia was carried out using a standardized self-administered questionnaire. A high response rate (96%) resulted in the enrollment of 553 men. Most participants 129/442 reported having intercourse with women and 51/111 reported having sex with other men. Most respondents (90%) engaged in high-risk sexual practices; only 2% knew their HIV-1 serostatus. Consistent condom use was reported by 20% of those who practised anal sex, and was even lower (5%) among men who had sex with women during menses. Heterosexuals exhibited a higher degree of risky sexual patterns than homosexual/bisexuals (P=0.01). In conclusion, high-risk sexual practices are prevalent among men in Bogotá, particularly heterosexuals, attesting to the urgent need for effective and specific interventions to prevent HIV transmission.

Where you live and where you shoot: suggestive data from Valencia, Spain.

Residence appears to exert influence over choices of venues for injection among intravenous drug users (IDUs) in Valencia, Spain. While living in their parents' homes, young IDUs may resort to high-risk venues for injection, particularly chutaderos in which used needles and syringes are often reused. Residence patterns of young IDUs in Spain may be highly similar to residence of IDUs in Italy and Puerto Rico, which also have AIDS epidemics dominated by IDUs rather than men who have sex with men. Intervention in these places needs to take contextual factors of residence into account for effective prevention of HIV infection.

The association between cigarette smoking and drug abuse in the United States.

Cigarette smoking has been identified as an independent risk factor for many human diseases. However, the association between cigarette smoking and illegal drug use has not been thoroughly investigated. We have analyzed the 1994 National Household Survey on Drug Abuse to clarify whether cigarette smoking has any effect on the initiation of illegal drug use. Data from 17,809 respondents completing the 1994 "new" (1994-B) questionnaire were analyzed. Logistic regression analyses were performed with the use of statistical package SUDAAN, taking into consideration the multistage sampling design. The results show that those who had smoked cigarettes were far more likely to use cocaine (OR = 7.5; 95% CI: 5.7-9.9), heroin (OR = 16.0; 95% CI: 6.8-37.9), crack (OR = 13.9; 95% CI: 7.9-24.5) and marijuana (OR = 7.3; 95% CI: 6.2-8.7). The associations are consistent across age-strata and remain after adjusting for race and gender. This study suggests that cigarette smoking may be a gateway drug to illegal drug use.

Adoption of injection practices in heroin users in Guangxi Province, China.

This preliminary study collected data from 326 heroin users in Guangxi Province, China, in 1997. Logistic regression analysis was performed to identify the risk factors for injection. Survival analysis identified factors independently associated with time from initiation of heroin use to adoption of injection. Four factors were independently associated with injection: number of friends who used heroin in the last year, duration of heroin use, dose of heroin consumed, and total number of times detoxified in drug treatment and rehabilitation centers. Only gender and duration of heroin use were independently associated with time to first injection. Median time to first injection was 11 months for males and 22 months for females. Median time to first injection varied by age. Median time to injection for those who used heroin for more than one year was 8.1 months; it was 19.1 months for on to five years of use, and 40.5 months for more than five years of use. This study's preliminary findings suggest that younger, more recent heroin users, and males are at increased risk of becoming injectors, a major risk behavior for HIV acquisition.

First injection and current risk factors for HIV among new and long-term injection drug users.

The purpose of this paper is to estimate HIV seroprevalence and to examine the injection and sexual risk behaviours of a cohort of active new heroin injectors who have initiated injection within the past four years and to compare their risk behaviours with those of long-term heroin injectors who initiated injection prior to January 1, 1985. A stratified network-based sample was used to recruit injection drug users (IDUs) from the streets of Miami-Dade, Florida. New IDUs displayed a significantly lower HIV seroprevalence than long-term injectors (13.3 versus 24.7%). Both new and long-term drug injectors exhibited a high level of current HIV risk behaviour. While new injectors were more likely than long-term injectors to practise safer injection behaviours at the initial injection episode, the current risk behaviours of new and long-term injectors are similar.

When obesity is desirable: a longitudinal study of the Miami HIV-1-infected drug abusers (MIDAS) cohort.

Despite widespread nutrient deficiencies, a substantial proportion of the MIDAS cohort exhibits obesity, which has been linked to immune dysregulation in other clinical settings. Herein, the effects of obesity on immune function, disease progression, and mortality were evaluated longitudinally in 125 HIV-1-seropositive drug users, with comparison measures in 148 HIV-1-seronegative controls. Data were collected at a community clinic from 1992 to 1996, before administration of highly active antiretroviral therapy. Results indicated that overweight/obesity, defined as body mass index (BMI; kg/m2) > or =27, was evident in 18% of the HIV-1-seropositive patients and 29% of the seronegative patients. At baseline, no significant immunologic differences were observed among lean, nonobese, and obese groups. Over an 18-month period, 60.5% of the nonobese HIV-1-seropositive patients exhibited a 25% decline in CD4 cell count, compared with 18% of the obese patients (p<.004). During the follow-up period, 38% of the lean and 13% of the nonobese study subjects died of HIV-1-related causes. Measurements of BMI were inversely associated with progression to death, independent of CD4 count <200 cells/mm3 (p<.02). These data suggest that mild-to-moderate obesity in HIV-1-infected chronic drug users does not impair immune function and is associated with better HIV-1-related survival.

HIV-1 RNA load in needles/syringes from shooting galleries in Miami: a preliminary laboratory report.

We quantified HIV-1 RNA load in rinses from needles/syringes (N/S) obtained at shooting galleries in Miami and also analyzed the rinses for antibodies for viral proteins. In rinses from 36 N/S that contained visible blood, 14 (39%) had detectable amounts of HIV-1 RNA. Numbers of copies of HIV-1 RNA ranged from the detection limit (400 copies/ml) to 268,000 copies/ml. We also detected antibodies to HIV-1 polypeptides in 34/36 (94%) of rinses from visibly contaminated N/S using Western blots specific for the HIV-1 proteins. No antibodies were detected in laboratory rinses from six visibly clean needles. The presence of HIV-1 RNA in N/S is an important indication of the risk created by N/S sharing as well as by shared paraphernalia and wash waters by injecting drug users.

Quality of life measures in the Miami HIV-1 infected drug abusers cohort: relationship to gender and disease status.

PURPOSE: This study examined activity, daily living, health, support, and outlook in HIV+ drug users. METHODS: Using the physician-administered Spitzer Index, the study assessed 75 HIV-1 seropositive men (n = 51) and women (n = 24) enrolled in the Miami HIV-1 Infected Drug Abusers Study (MIDAS). RESULTS: Total composite scores were significantly lower in the HIV-1 infected women than the men (p = .03). Significant gender differences were observed in activity assessment, independent of disease status, with women six times as likely to have lower activity scores (p = .0038). Most women (45%) in this category were homeless or marginally housed, compared to 11 percent of the men. Additionally, women with low activity scores had less social support than women with high activity scores. Cocaine use was significantly related to reports of normal activity, and varied across genders; more men used cocaine than women (p = .03). Compared to non-AIDS participants, AIDS patients were more likely to have lower scores in health (p = .009) and poorer outlook (p = .03). IMPLICATIONS: These findings reveal specific deficits in areas of psychosocial capacity, particularly in HIV-1 infected women who abuse drugs, that may need to be strengthened in order to enhance function and adherence to treatment, as well as well-being.

Lemon juice as a solvent for heroin in Spain.

Preliminary observations and responses to interviews in Valencia, Spain reveal that injecting drug users (IDUs) dissolve heroin before injection with two or three drops of lemon juice. Solution in lemon juice makes heating of heroin in water unnecessary. This pattern apparently developed spontaneously in Spain, but is almost unknown elsewhere in the world. Its implications for IDUs' health remain speculative, but use of lemon juice to dissolve heroin for injection deserves further scientific study.

Intrinsic localized modes and chaos in damped driven rotator lattices.

It is shown that intrinsic localized rotational modes (ILRMs) in parametrically driven damped lattices of coupled classical dipole rotators can become chaotic without losing their localized character. Insight into this behavior is obtained by means of a nonlinear stability analysis. Moreover, we discuss a robust scheme for exploiting a spatially extended chaotic state to generate stationary randomly spaced arrays of driven ILRMs, and show that the associated absorption exhibits unusual signatures.

Use of needles and syringes in Miami and Valencia: observations of high and low availability.

Two studies engaged in gathering data on injecting drug users (IDUs) employed supplementary resources to enhance their ethnographic components and compare patterns of use of needles/syringes (n/s) in two geographically similar but culturally distinct cities. Despite its policy of making n/s highly available at fair prices, Valencia, Spain, has markedly higher rates of HIV seroprevalence among its IDUs than does Miami, Florida, where possession of n/s is illegal. Ethnographically based models that track IDUs through choices of injection venues help to explain this difference. Inability of IDUs in Valencia to use their own domiciles as venues for injection contrasts sharply with problems of Miami IDUs, who have access to houses but have difficulty finding n/s. This research suggests that intervention in Valencia needs to focus on how people select places where they inject, and intervention in Miami needs to focus on improving availability of n/s.

The effect of marital status on survival in late-stage cancer patients: an analysis based on surveillance, epidemiology, and end results (SEER) data, in the United States.

Recently findings that marital status is associated with survival in patients with late-stage prostate cancer led to an examination of the generalizability of this association for all cancers. We restricted the investigation to patients with late-stage cancer using population-based data collected from 261,070 patients with late-stage cancer at multiple sites in the United States to determine relations between marital status and survival. After controlling for age, race, and treatment, married patients with cancers of all major primary sites had significantly better survival than single, separated, divorced, or widowed patients. Although single and widowed patients had the poorest prognosis in general, single patients appeared to show the most consistently poor survival across the different types of cancers. Survival differences by marital status were more pronounced in men than in women. This observation raises the possibility that some characteristics associated with being married delay death from cancer. These findings require investigators to ask new questions about the effect of being married and its possible correlates, such as general health status, access to health care, and socioeconomic status. Known correlates of marital status, such as available social support and social isolation also merit attention in relation to these findings.

HIV-1 infection in women is associated with severe nutritional deficiencies.

Nutritional deficiencies may contribute to immune dysregulation, and have been shown to be sensitive markers of HIV-1 disease progression. Only limited information exists, however, regarding the nutritional profile of HIV-1-seropositive drug abusers. Immune and nutritional measurements were obtained in a subsample of 125 subjects from a larger cohort of drug users being followed for HIV-1 infection and cofactors of disease progression. Nutritional deficiencies, particularly vitamins A, E, and zinc, were widespread with up to 86% of the drug users exhibiting at least one nutritional alteration. Although immune parameters (CD4 count, CD8 count, beta2-microglobulin) were similar in the HIV-1-infected men and women, women had significantly poorer overall nutritional status, as measured by plasma proteins, which are considered to be sensitive markers of malnutrition. A comparison of individuals with advanced disease (CD4 count <200/mm3) revealed significantly lower levels of plasma prealbumin (p < .01), selenium, (p < .05), and greater deficiency of vitamins A (p < .01) and E (p < .05) in women than in men. The greater severity of nutritional deficiencies noted in HIV-1-infected women may be an important determinant of disease progression and survival.

HIV testing among Haitian women: lessons in the recognition of risk.

Haitian women in Miami, Florida, responded to recruitment for testing of HIV antibody serostatus in ways that demonstrated the value of ethnographic methods for studying reactions to this kind of test, especially pre- and posttest counseling sessions. A total of 155 women between 14 and 61 years old, recruited in Miami in 1992 and 1993, participated. Response to testing identified three primary obstacles to the women's understanding of content presented in pre- and posttest counseling sessions: (1) their confusion about the meaning of positive versus negative, (2) the investigators' difficulty in communicating the concept of antibody, and (3) vagueness of the concept of window period between exposure and presentation of antibody. Retesting of a subset of Haitian participants helped to define sexual risk among these women in terms of having partners who had other partners and perception of supernatural risk.