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Biomedical subjects

T S Jones

Publications and source records attributed to T S Jones.

At least 19 recordsLinked to original sources
PubMed2006

Photophysics of PTCDA and Me-PTCDI thin films: effects of growth temperature.

The effect of deposition temperature on the photophysical properties of 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and N,N'-dimethylperylene-3,4,9,10-bis(dicarboximide) (Me-PTCDI) films is investigated with steady-state and time-resolved spectroscopy. Atomic force microscopy (AFM) images of the film surfaces show an increase in the dimensions of crystallites with substrate temperature, culminating in the formation of elongated crystallites on substrates held close to the sublimation temperature. In contrast, despite an improvement in the crystal quality, X-ray diffraction (XRD) studies indicate that the substrate temperature has a negligible effect on the molecular orientation; the PTCDA and Me-PTCDI molecules align parallel and tilted to the substrate surface, respectively. Both materials exhibit characteristic absorption, due to mixing between charge-transfer and Frenkel species, and broad structureless photoluminescence. Growth at elevated temperatures gives rise to increased low-energy absorption, attributed to the formation of charge-transfer species, and enhanced blue-shifted emission, although the effects are less pronounced for Me-PTCDI. Time-correlated single-photon counting data indicate that the enhancement coincides with a lengthening of the fluorescence decays, over the whole emission spectrum.

Journal Article↗
PubMed2005

Charge recombination in CuPc/PTCDA thin films.

The recombination kinetics of photogenerated charge carriers in perylene-3, 4, 9, 10-tetracarboxylic dianhydride (PTCDA) and copper phthalocyanine (CuPc) thin films grown by organic molecular beam deposition have been studied using transient absorption spectroscopy. Optical excitation is observed to generate long-lived polaron states, which exhibit power law recombination dynamics on time scales from microseconds to milliseconds. Studies as a function of excitation density and temperature, and comparison between heterostructures and PTCDA single layers, all indicate that this power law behavior results from trapping of PTCDA- polarons in localized states, with an estimated trap state density of approximately 6 x 10(17) polarons cm(-3). This recombination behavior is found to be remarkably similar to that previously observed for polymer/fullerene blends, suggesting that it may be generic to a range of semiconducting materials.

Journal Article↗
PubMed2004

First report of human immunodeficiency virus transmission via an RNA-screened blood donation.

BACKGROUND AND OBJECTIVES: Blood banks in the USA have recently introduced minipool nucleic acid amplification testing (MP-NAT) of blood products to reduce the transmission of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) by transfusions. However, MP-NAT is limited in its ability to detect preseroconversion samples with very low viral RNA loads. MATERIALS AND METHODS: To determine whether a red blood cell unit, from an MP-NAT-negative donation, transmitted HIV when transfused to a patient, we compared the viral sequences from the blood donor and recipient. The implicated donation was also tested by commercially available NAT assays at a range of dilution factors to determine whether the infectious unit could have been detected using individual-donation NAT (ID-NAT). RESULTS: Phylogenetic linkage of HIV sequences in the blood donor and recipient confirmed the transmission of HIV by blood transfusion, the first such case identified since introduction of MP-NAT screening in 1999. Viral RNA was reliably detected by ID-NAT, but only inconsistently detected by MP-NAT. CONCLUSIONS: Even following the introduction of MP-NAT, a preseroconversion donation with a viral load of <or= 150 copies of RNA/ml went undetected and resulted in an HIV transmission. Implementation of ID-NAT will further reduce such rare transmissions, but at a considerable cost per infectious unit interdicted.

Adult↗
PubMed2000

Syringe laws and pharmacy regulations are structural constraints on HIV prevention in the US.

OBJECTIVE: To review the legal and regulatory barriers that restrict pharmacy sales of syringes to injection drug users (IDUs) and to discuss how reducing these barriers can facilitate access to sterile syringes for IDUs and improve HIV prevention. BACKGROUND: IDUs' access to sterile syringes from community pharmacies in the United States is limited by state laws and regulations governing syringe sales. Restricted availability of sterile syringes from pharmacies is a structural barrier that greatly impedes HIV prevention for IDUs, who often share and reuse syringes because they cannot obtain and possess sterile syringes. These high-risk behaviors contribute to the transmission of HIV and other blood-borne pathogens among IDUs, their sexual partners, and their children. STATE EXPERIENCES: In Connecticut, because of high HIV prevalence among IDUs, restrictive syringe laws were changed. After the legal changes in Connecticut, both pharmacy sales of syringes in areas of high drug use and purchases of syringes in pharmacies (reported by IDUs) increased, while syringe sharing (reported by IDUs) decreased. Maine and Minnesota have made similar changes in laws. CONCLUSIONS: Increasing access to sterile syringes through pharmacies requires the repeal or modification of legal barriers. Pharmacy sale of syringes to IDUs is an inexpensive HIV prevention intervention with the potential to substantially reduce HIV transmission. Further studies are needed to document how changes to legal barriers can influence HIV prevention for IDUs.

Connecticut↗
PubMed1999

Prevalence of sexual and drug-related HIV risk behaviors in the U.S. adult population: results of the 1996 National Household Survey on Drug Abuse.

CONTEXT: Data on the prevalence of HIV risk behavior that are representative of the general population are needed to help evaluate the effectiveness of prevention programs. OBJECTIVE: To use data from a large national interview survey to make estimates of the prevalence of sexual and drug-related HIV risk behaviors in the adult population of the United States. DESIGN: Nationally representative cross-sectional survey with in-person interviews collecting information on drug use and sexual behavior. SETTING AND PARTICIPANTS: 12,381 U.S. adults aged between 18 and 59 who were respondents to the 1996 National Household Survey on Drug Abuse, as part of sample of the noninstitutionalized population. Interviews took place in respondents homes using face-to-face interviewer-administered and self-administered questionnaires. RESULTS: In total, 2.8% of respondents were classified as having increased risk for HIV through sexual behavior; this represents 3.9 million persons. 1.7% reported some degree of risk through drug-related behaviors, representing 1.2 million persons. 3.5% of adults (5 million persons) were found to have some degree of HIV risk from sexual or drug-related behavior. Persons who were at risk through drug behavior were much more likely than others to be at risk through sexual behavior. Condom use was not related to HIV risk, although having a recent HIV test was found to be. Among those who reported some behaviors that placed them at increased risk for HIV infection, only 22% used a condom the last time they had sex with a regular partner. CONCLUSIONS: The high rate of sexual risk behavior on the part of drug users suggests increasing condom use for this group should be a priority goal for programs, especially condom use with main partners. Survey work needs to be continued and improved to make it possible to assess the impact of successful local prevention efforts on national rates of HIV risk behavior.

Adolescent↗
PubMed1999

Syringe disposal options for injection drug users: a community-based perspective.

This study was a qualitative exploration of syringe disposal interventions for injection drug users (IDUs). Data were collected through in-depth interviews with 26 community members who injected drugs and 32 noninjecting community members in Atlanta, Georgia. Both groups supported syringe exchange programs as syringe disposal interventions, while noninjecting community members favored a one-way drop box. IDUs identified fear of arrest for possession of syringes as the most salient barrier to safe syringe disposal, revealing the negative consequences of drug paraphernalia laws.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Minimizing process induced prooxidant stresses.

The adverse effects of trace metals, heat, steam and other conditions encountered in food processing relate to the acceleration of development of rancidity. Measures to retard oxidation of lipids, vitamins, pigments and proteins include elimination of prooxidants, removal of oxygen and use of blends of inhibitors formulated for specific substrates.

Animals↗
PubMed1998

A sterile syringe for every drug user injection: how many injections take place annually, and how might pharmacists contribute to syringe distribution?

Our objectives were to estimate the annual number of injections by injection drug users (IDUs) in the United States of America, and to describe the potential role of pharmacists in providing IDUs with a sterile syringe for every injection. We estimated the number of annual injections by IDUs for the United States, selected U.S. states, and selected U.S. cities according to the following formula: number of injections per year = (number of IDUs) x (average number of injections per IDU per day) x 365. Data were obtained from published articles, personal communications with local experts, and selected national databases. We also reviewed published and unpublished studies of pharmacy kits, pharmacist attitudes, and pharmacist practices in the United States and abroad. Between 920 million and 1.7 billion injections by IDUs take place each year in the United States. We estimated 12 million injections per year in San Francisco and >80 million in New York City. A similar number of syringes would be needed to satisfy the goal of a sterile syringe for every injection. Pharmacy-based strategies, including the sale of kits for injection drug use, have provided sterile syringes to IDUs in Europe, Australia, and New Zealand. Modification of laws restricting syringe purchase and possession has led to marked increases in purchase of syringes from pharmacies and reductions in needle-sharing. In conclusion, large numbers of syringes would be required to provide a sterile syringe for every injection, but significant numbers of pharmacists seem to be willing to play a central role in syringe sale and distribution. Outreach programs should emphasize that using a sterile syringe for every injection is the optimal HIV prevention practice for IDUs who cannot or will not stop injecting. Pharmacy-based syringe sale or distribution has the potential to augment current efforts to prevent HIV infection in IDUs, their sex partners, and their children.

Australia↗
PubMed1998

Arrests and incarceration of injection drug users for syringe possession in Massachusetts: implications for HIV prevention.

Multiperson use of syringes is a major risk behavior responsible for the spread of HIV-1 among injection drug users (IDUs). In Massachusetts, two laws regulate syringes: one is a prescription law prohibiting possession or purchase of syringes without a prescription, and the other makes it illegal to possess drug paraphernalia, including syringes. In 1993, Massachusetts amended the prescription law to permit the establishment of syringe exchange programs in two cities. Enrolled participants are allowed to possess syringes anywhere in the state, and about 5% of the estimated 40,000 IDUs in Massachusetts are program participants. To understand how HIV prevention efforts with active IDUs may be constrained by the enforcement of laws criminalizing possession of syringes after the amendment in the law, we reviewed data from multiple sources to assess the number of arrests for syringe possession in 10 large cities in Massachusetts to evaluate incarceration rates and lengths of sentences for those convicted of syringe possession and to estimate costs of incarceration for those convicted of syringe possession. At least 824 persons were arrested for syringe possession in 1995. In examining the data on convictions, we found that 417 persons were convicted in 1994 of syringe possession in the absence of other serious charges, and of these, 41.0% were sentenced to incarceration. The average sentence imposed was 5 months (range, 3 days-2 years). Assuming that those convicted serve about two thirds of their sentences, the cost of incarceration was estimated at $1,140,183 excluding costs for arrest, pretrial detention, prosecution, or other costs of enforcement. Costs for incarcerating persons convicted of both syringe and drug possession were not included; the total cost of incarceration of persons convicted of possession of a syringe, with or without other major charges, is probably considerably higher. Had these funds been allocated to pay for drug treatment, 1629 admissions to drug detoxification programs could have been purchased. Retaining drug paraphernalia and syringe prescription laws in Massachusetts may contribute to HIV transmission. These findings support the recommendation of the American Medical Association to modify drug paraphernalia laws so that IDUs can purchase and possess syringes without a prescription.

Boston↗
PubMed1998

Injection and syringe sharing among HIV-infected injection drug users: implications for prevention of HIV transmission. Supplement to HIV/AIDS Surveillance Group.

Because HIV-infected injection drug users (IDUs) can transmit HIV infection, we investigated factors associated with sharing of syringes in the past year among IDUs infected with HIV. We analyzed data from an interview survey of 11,757 persons > or = 18 years of age with HIV or AIDS between June 1990 and August 1995 who were reported to 12 state or city health departments in the United States. Of the 1527 persons who had ever shared syringes and reported injecting in the 5 years before the interview, 786 (51%) had injected in the year before interview, and of these, 391 (50%) had shared during that year. IDUs who were aware of their HIV infection for >1 year were less likely to share (43%) than those who were aware of their infection for 1 year or less (65%, adjusted odds ratio=2.15, 95% confidence interval, 1.52-3.03). The only statistically significant time trend was that the proportion of IDUs from Connecticut who shared decreased from 71% in 1992 to 29% in 1995. This trend appears to be related to the 1992 changes in Connecticut laws that allowed purchase and possession of syringes without a prescription. Because many HIV-infected IDUs continue to inject and share, prevention efforts should be aimed at HIV-infected IDUs to prevent transmission of HIV. Early HIV diagnosis and access to sterile syringes may be important methods for reducing syringe sharing by HIV-infected IDUs.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Access to sterile syringes in Maine: pharmacy practice after the 1993 repeal of the syringe prescription law.

In October 1993, the Maine legislature repealed the prescription law regulating the sale of syringes. The new law allowed but did not require licensed pharmacists to dispense syringes without a prescription to anyone 18 years of age or older. From November 1995 to January 1996, we conducted a telephone survey of 208 Maine pharmacists to evaluate the sale of syringes with and without a prescription and to assess pharmacists' willingness to sell syringes without a prescription. We found that 94% of pharmacists were willing, in all cases or at the discretion of the pharmacist, to sell syringes without a prescription. However, when asked specifically about willingness to sell syringes without a prescription to suspected injection drug users (IDUs) > or =18 years of age, 47% were willing, 40% were not willing, and 13% did not know or declined to answer. Pharmacists reported other requirements for the purchase of syringes without a prescription, such as the requirement for the customer to provide a reasonable justification for the purchase. In all, there were 31 (15%) pharmacists in the sample willing to sell syringes to without a prescription with no additional requirements for purchase to suspected IDUs as permitted by law. There were few negative incidents reported involving IDUs and the sale of syringes without a prescription since amendment of the law. Although sales of syringes without a prescription were reported, the numbers sold fell short of the estimated number of syringes required for IDUs in Maine to use a new syringe for every injection. Despite the change in the prescription law intended to increase access to syringes, the data suggest barriers such as drug paraphernalia laws and pharmacy policies may prevent IDUs from purchasing syringes and contribute to ongoing transmission of HIV. Amendment of the drug paraphernalia and syringe possession laws, clarification of the legitimate medical purpose of access to sterile syringes for IDUs, and offering pharmacists continuing education on the prevention of blood-borne disease appear to be necessary steps in the effort to decrease the transmission of HIV among IDUs in Maine.

Adult↗
PubMed1998

Impact of the change in Connecticut syringe prescription laws on pharmacy sales and pharmacy managers' practices.

We assessed the impact of the 1992 change in Connecticut syringe prescription laws on pharmacy sales and pharmacy managers' sales practices. A mail survey was conducted in 1994 of all current pharmacy managers in the five largest cities in Connecticut (Hartford, New Haven, Waterbury, Bridgeport, and Stamford) and a random sample of those practicing in all other areas. Of these, 89.3% of the pharmacies in the five largest cities and 85.1% in the other areas had ever sold syringes without a prescription since the July 1992 law went into effect. Most pharmacists identified safety issues as very important in their personal decision about the sale of syringes without a prescription. Although the purpose of the change in the prescription law was to provide expanded access to sterile syringes by injection drug users (IDUs), only 31.4% of the managers who were allowed to sell in all instances and 18.1% of those who sold at their discretion were very willing to sell syringes to IDUs. In the logistic regression model of pharmacies with a sell-in-all-instances policy, the perceived benefit of the sale of syringes on health and community well-being was the only influence independently associated with managers support for nonprescription sales. Overall, managers reported they did not know what other pharmacists thought (40.4%) or did (42.9%) regarding the sale of syringes. When pharmacists had discretion over syringe sales, managers' beliefs about what other Connecticut pharmacists thought and did about the nonprescription sale of syringes remained a significant influence on the degree of support for sales. Most pharmacies implemented and maintained policies permitting the sale of syringes without a prescription. Several issues, including risk of discarded contaminated syringes around pharmacies and in the community and reluctance to sell to IDUs, reduced pharmacists willingness to sell syringes. Efforts to incorporate pharmacists as active partners in HIV prevention in IDUs should promote the sale of syringes without a prescription to IDUs as acceptable public health practice.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Community-based programs for safe disposal of used needles and syringes.

OBJECTIVES: To review issues related to discarded syringes in the community and to describe community-based programs for the safe disposal of used needles and syringes. METHODS: We used the medical literature and chain referral to identify community-based syringe disposal programs other than syringe exchange programs (SEPs). We held a workshop in June 1996 involving staff from disposal programs; manufacturers of syringes, sharps containers, and other disposal devices; solid waste companies; public health staff; and researchers. RESULTS: Fifteen programs for the safe disposal of syringes were identified in the United States, Canada, and Australia. Of these, 12 primarily served persons with diabetes who use insulin, and 3 primarily served injection drug users (IDUs). The programs used three major strategies: puncture-resistant containers discarded in trash, community drop boxes, and sharps containers turned in for biohazard disposal at community sites, hospitals, or pharmacies. Participants in the workshop described key points in developing syringe disposal programs. Programs should involve pharmacists, physicians, waste disposal companies, public health departments, hospitals, diabetes educators, persons with diabetes who use insulin, and IDUs. For IDUs, criminal penalties for possession of syringes are a substantial deterrent to participation in community efforts to safely dispose of used syringes. The multiple and sometimes conflicting local, state, and federal laws and regulations concerning medical waste hinder development of multistate or national approaches to the safe disposal of syringes. More information is needed on community-based syringe disposal programs. CONCLUSION: Communities in the United States, Canada, and Australia have developed different approaches to achieve safe disposal of used syringes.

Australia↗
PubMed1998

Operation Red Box: a pilot project of needle and syringe drop boxes for injection drug users in East Baltimore.

We assessed the acceptability and the use of a community-based needle and syringe disposal project designed to serve injection drug users. In June 1996, three surplus U.S. mail collection boxes were painted red and used as syringe and needle drop boxes in locations with high drug use in East Baltimore. Acceptance of the drop boxes was measured by focus groups of residents, drug users, and police, held before and after project implementation. Use was measured by weekly counts of needles recovered from the red boxes. A sample of all deposited needles was randomly chosen for needle washing and subsequent HIV antibody testing. Community impact was measured by systematic surveys of needles discarded on public sidewalks, in areas with and areas without drop boxes. Before implementation, members of focus groups expressed concerns that drop boxes could convey mixed messages to youth (e.g., seeming to condone drug use), might result in increased loitering, and could further community stigmatization. After project implementation, all focus groups expressed support of project expansion. In the first 10 months, 2971 needles were collected. Of 156 needles tested, 10.9% were positive for HIV antibody. Needle counts on the street showed no significant change in red box areas compared with control areas. In this pilot project, red boxes were accepted by the community and drug users. Police officers also used the boxes to dispose of confiscated needles. Although limited in the number of drop boxes and follow-up time, this pilot project shows promise as a community-based method of safe needle disposal.

Adolescent↗
PubMed1998

An economic analysis of needle exchange and pharmacy-based programs to increase sterile syringe availability for injection drug users.

Our objectives were to estimate the cost per syringe distributed for five syringe distribution strategies (a needle exchange program [NEP], a pharmacy-based NEP, free pharmacy distribution of pharmacy kits, sale of such pharmacy kits to injection drug users [IDUs], and sale of syringes in pharmacies); to assess the total costs of these strategies; and to conduct an economic analysis of these strategies in preventing HIV infection in IDUs. We estimated the costs for NEPs by using data from previous research; costs for the four pharmacy-based strategies were resource-based. Using estimates of the number of syringes required to provide a sterile syringe for each IDU injection, we estimated the total costs of the strategies in three representative U.S. cities. The lifetime cost of treating a person for HIV infection, discounted into current value, was used to estimate the number of syringes that could be distributed for that amount by the five strategies and thus the number of IDUs who could be ensured a sterile syringe for each injection. We then conducted a threshold analysis for calculating the annual HIV seroincidence for the program to be cost-neutral. The cost per syringe distributed in U.S. dollars was $0.97 for the NEP, $0.37 for the pharmacy-based NEP, $0.64 for pharmacy kit distribution, $0.43 for pharmacy kit sale, and $0.15 for syringe sale. The total annual cost in U.S. dollars of providing 50% of the syringes needed for a single syringe for every injection ranged from $6 to $40 million for New York City, from $1 to $6 million for San Francisco, and from $30,000 to $200,000 for Dayton, Ohio. The annual HIV seroincidence for the program to be cost-neutral compared with the cost of medical treatment for HIV injections was 2.1% for the NEP, 0.8% for the pharmacy NEP, 1.4% for pharmacy kit distribution, 0.9% for pharmacy kit sale, and 0.3% for syringe sale. All five strategies could distribute syringes at relatively low unit costs; NEPs would be the most expensive and syringe sales would be the cheapest. At annual seroincidences exceeding 2.1%, all strategies are likely to be cost-saving to society.

Costs and Cost Analysis↗
PubMed1998

Cost and cost-effectiveness of increasing access to sterile syringes and needles as an HIV prevention intervention in the United States.

We determined the cost of increasing access of injection drug users (IDUs) to sterile syringes and needles as an HIV prevention intervention in the United States and the cost per HIV infection averted by such a program. We considered a hypothetical cohort of 1 million active IDUs in the United States. Standard methods were used to estimate the cost and cost-effectiveness of policies to increase access to sterile syringes and syringe disposal at various levels of coverage (e.g., a 100% coverage level would ensure access to a sterile syringe for each injection given current levels of illicit drug injection in the United States; a 50% coverage level would ensure access to one half of the required syringes). A mathematical model of HIV transmission was employed to link programmatic coverage levels with estimates of numbers of HIV infections averted. A policy of funding syringe exchange programs, pharmacy sales, and syringe disposal to cover all illicit drug injections would cost just over $423 million U.S. for 1 year. One third of these costs would be paid for as out-of-pocket expenditures by IDUs purchasing syringes in pharmacies. Compared with the status quo, this policy would cost an estimated $34,278 U.S. per HIV infection averted, a figure well under the estimated lifetime costs of medical care for a person with HIV infection. At very high levels of coverage (>88%), the marginal cost-effectiveness of increased program coverage becomes less favorable. Although the total costs of funding large-scale IDU access to sterile syringes and disposal seem high, the economic benefits are substantial. Even at high levels of coverage, such funding would save society money. As part of a comprehensive program of HIV prevention, policies to increase IDUs access to sterile syringes urgently need further consideration by public health decision makers.

Cost-Benefit Analysis↗