Hepatitis C and cigarette smoking behavior: Themes from focus groups

INTRODUCTION

People with chronic hepatitis C virus (HCV; PWHC) use cigarettes at a much higher prevalence than other individuals, and smoking can exacerbate the harms specifically related to HCV (e.g., hepatocellular carcinoma). Little is known about factors related to cigarette use among PWHC. This study examined focus group data to explore beliefs and behaviors related to cigarette use among PWHC.

METHODS

Qualitative data from two focus groups of PWHC reporting current cigarette smoking (n=15, 60% male) were collected using a semi-structured interview guide. Participants were asked about reasons for smoking, barriers to quitting smoking, and the relationship of HCV to smoking. Focus groups were transcribed verbatim and coded in NVivo 12. Four coders examined themes that arose in the focus groups. Common themes are described and supported with quotes.

RESULTS

Reasons for smoking included addiction to cigarettes, stress, substituting cigarettes for other drugs, and social norms, while reasons for quitting included health and being free from the use of all drugs. Barriers to quitting included concerns about coping with stress, weight gain, and having a lack of support for and education about quitting. Many participants believed there was a link between smoking and HCV and discussed smoking in relation to the stress of an HCV diagnosis.

CONCLUSIONS

Participants identified both HCV-related and non-HCV-related aspects of cigarette smoking and cessation-related behaviors that could be targeted in cessation treatment. More research is needed to identify the best treatment approaches that reduce the significant medical consequences of cigarette use among PWHC.

IMPLICATIONS

People with chronic hepatitis C virus (HCV; PWHC) smoke cigarettes at a high prevalence, yet little is known about their smoking behaviors. Moreover, there are no cessation treatments targeting PWHC. This is the first study to collect focus group data from PWHC who smoke in order to identify reasons for cigarette use (HCV-related and non-HCV-related), and motivators and barriers to quitting cigarettes. PWHC report using cigarettes to cope with the stress of an HCV diagnosis and to celebrate HCV cure. These findings suggest there are specific times during the HCV care continuum where providers can aid with cessation efforts.

Impact of reduced restrictions on buprenorphine prescribing during COVID-19 among patients in a community-based treatment program

Background

Medications such as buprenorphine are considered the gold standard for the treatment of opioid use disorders. This study aimed to determine whether less restrictive buprenorphine prescribing practices during the COVID-19 pandemic impacted retention in and adherence to buprenorphine among patients accessing treatment from 2018-2020 at a community-based syringe services program.

Methods

In this retrospective cohort study, we compared retention in treatment before and during the COVID-19 pandemic. Then, with relaxed restrictions acting as the intervention in a natural experiment, we conducted a sub-analysis of "continuity participants" who accessed treatment services both before and during the COVID-19 period. Records of 418 historical control patients treated with buprenorphine before COVID-19 were compared to 88 patients enrolled during COVID-19 (n=43 remote telemedicine and n=45 remote provider with patient on-site). Cox proportional hazards regressions were used to assess risk factors for treatment discontinuation. The sub-analysis used proportion of days covered (PDC) differences before and during COVID-19 (n=164) for a paired analysis in a nonparametric bootstrap test.

Results

The risk of discontinuation was 71% lower in those accessing remote telemedicine during COVID-19 (HR=0.29; CI: 0.18, 0.47) and 51% lower in those accessing their remote provider onsite during COVID-19 (HR=0.49; CI:0.31, 0.77), compared to the historical control group. The average PDC did not significantly differ before and during COVID-19 (difference=2.4%; CI:-0.6%, 5.3%).

Conclusions

The risk of discontinuing treatment was lower in both COVID-19 treatment groups compared to historical controls. Less restrictive buprenorphine prescribing guidelines during COVID-19 led to improved retention in care over 6-months.

Impact of Co-occurring Drug Use, Hazardous Alcohol Use, and Mental Health Disorders on Drug Use Patterns in People With HIV and Hepatitis C Virus Infection

Drug use, hazardous alcohol use, and mental health disorders are prevalent among people with HIV and hepatitis C virus (HCV) infection. Co-occurrence of alcohol use and depression negatively impacts substance use patterns. Nevertheless, HCV treatment provides a promising opportunity to identify and address co-occurring drug use, hazardous alcohol use, and mental health disorders.

Non-adherence to LDV/SOF did not predict SVR in a randomized controlled trial of HIV/HCV coinfected persons who use drugs

BACKGROUND

Eliminating Hepatitis C Virus (HCV) will require effective treatment delivery to persons with substance use disorders (SUDs). We evaluated the relationship between ledipasvir/sofosbuvir treatment persistence (receiving 84 tablets), adherence, and sustained virologic response (SVR) in persons with HIV/HCV coinfection.

METHODS

Of the 144 participants with HIV/HCV and SUDs, 110 initiated a 12-week treatment course under one of three conditions (usual care, peer mentors, and cash incentives). We used self-report, pharmacy pill counts, and expected date of refill to examine adherence. Persistent participants were categorized as high adherence (taking ≥90% of doses) or low adherence (taking <90% of doses).

RESULTS

Most participants persisted on treatment after initiation (n=105), with 95% (n=100) achieving SVR. One-third (34%) of participants had moderate/heavy alcohol use by the biomarker phosphatidylethanol (PEth ≥50 ng/mL), and 44% had urine toxicology positive for cocaine or heroin at enrollment. The proportion of persons with high adherence was 72% (n=76) and low adherence, 28%. Although low adherence was associated with moderate/heavy alcohol use by PEth (RR 2.77, 95% CI 1.50-5.12), SVR did not vary according to adherence (p=0.702), and most participants (97%) with low adherence achieved SVR.

CONCLUSION

Treatment persistence led to high SVR rates among persons with HIV/HCV, despite imperfect adherence and SUDs.

Prevalence and Correlates of Syringe Disposal Box Use in a Philadelphia Neighborhood with High Levels of Public Drug Injection

Background: Philadelphia (Pennsylvania, USA) is facing an unprecedented public health crisis due to fentanyl use. To combat drug-related litter, the Philadelphia Department of Public Health installed 7 public syringe disposal boxes (SDB) in Kensington, the neighborhood most impacted by the opioid crisis and home to a syringe exchange. Methods: We used street- and business-intercepts to recruit residents (N=358) and business owners/staff (N=78) who completed a brief survey with two binary items measuring observing and using SDB. Multivariable logistic regression was used to assess factors independently associated with SDB observance and use. Results: 78% (340/436) observed SDB and 34.1% (116/340) had ever used SDB among those who had seen them. Unstably housed persons had 4.3 times greater odds of observing SDB (Adjusted odds ratio [aOR= 4.29; 95% confidence interval [CI]: 1.56, 11.82) and had 2.5 times greater odds of using SDB (aOR = 2.51; 95% CI: 1.33, 4.74) as did people who use opioids (aOR = 2.61; 95% CI: 1.45, 4.72). Among individuals reporting opioid use who also saw SDB (n=123), those who were unstably housed were more likely to use SDB than those with stable housing (67.8% vs 45.3%, p=.012). Conclusion: These results suggest Kensington residents, especially those who are unstably housed, use SDB once they see them in the neighborhood.

Network-based recruitment of people who inject drugs for hepatitis C testing and linkage to care

Although oral direct-acting agent (DAA) therapies have the potential to reduce the burden of hepatitis C virus (HCV) infection, treatment uptake remains low, particularly among people who inject drugs (PWID). This study examined the feasibility of an innovative peer-based recruitment strategy to engage PWID in HCV testing and treatment. We interviewed an initial set of HCV antibody-positive PWID as 'primary indexes' to gather demographic, drug use, health information and drug network characteristics. Primary indexes were then briefly educated on HCV and its treatment and encouraged to recruit their injection drug 'network members' for HCV testing and linkage to care. Eligible network members were enrolled as 'secondary indexes' and completed the same index study procedures. In sum, 17 of 36 primary indexes initiated the recruitment of 64 network members who were HCV antibody positive and eligible to become indexes. In multivariable analysis, successful recruitment of at least one network member was positively associated with prior HCV treatment (OR 2.80; CI [1.01, 7.72]), daily or more injection drug use (OR 2.38; CI [1.04, 5.47]), and a higher number of injection drug network members (OR 1.20; CI [1.01, 1.42]). Among the 69 participants with chronic HCV not previously linked to HCV care at enrolment, 91% (n = 63) completed a linkage to HCV care appointment, 45% (n = 31) scheduled an appointment with an HCV provider, and 20% (n = 14) initiated HCV therapy. These findings suggest a potential benefit for peer-driven, network-based interventions focused on HCV treatment-experienced PWID as a mechanism to increase HCV linkage to care.

Unreported alcohol use was common but did not impact hepatitis C cure in HIV-infected persons who use drugs

We investigated the prevalence and impact of heavy alcohol use on the hepatitis C virus (HCV) care continuum amongst HIV/HCV co-infected persons who use drugs. In the CHAMPS study, 144 HIV/HCV co-infected persons were randomized to contingent cash incentives, peer mentors and usual care to evaluate the impact on HCV care. Alcohol use was ascertained using the 10-item AUDIT (hazardous: male ≥8, female ≥4) and phosphatidylethanol (PEth) (heavy: ≥50 ng/mL), an alcohol biomarker. Log binomial regression was used to evaluate the association between heavy alcohol use and failure to initiate treatment and to achieve sustained virologic response (SVR). Of the 135 participants with PEth data, median age was 55 years, 59% were male, 92% were Black, 91% reported a history of drug use, and 97% were on antiretroviral therapy. Hazardous drinking was reported on AUDIT by 28% of participants, and 35% had heavy alcohol use by PEth. Of the 47 individuals with a PEth ≥50 ng/mL, 23 (49%) reported no or minimal alcohol use by AUDIT. HCV treatment was initiated in 103 of 135 participants, and SVR was achieved in 92%. PEth ≥50 ng/mL (Relative Risk [RR] 0.72, 95% CI 0.35-1.48) was not significantly associated with failure to initiate HCV treatment or failure to achieve SVR (RR 0.85, 95% CI 0.46-1.57).In conclusion, alcohol use was common and frequently not detected by self-report. However, heavy alcohol use, even when measured objectively, was not associated with failure to initiate HCV treatment or to achieve cure.

Can Slot-Machine Reward Schedules Induce Gambling Addiction in Rats?

Similar to drugs of abuse, random-ratio reward schedules are highly motivating and, in humans, are thought to foster gambling addiction. Animal gambling models, however, have not yet demonstrated the compulsivity so characteristic of drug addiction. Three criteria have been used to evaluate addiction-like behavior in drug models: (1) response inhibition when reward is not available, (2) persistence under a progressive ratio schedule, in which the response-to-reward ratio is stretched, and (3) persistence in spite of punishment. We tested whether prolonged exposure (6 weeks) to a gambling-like reward schedule would induce addiction-like symptoms in rats. In two studies, separate groups were trained to respond to either random- or fixed-ratio schedules for food reward. We found that rats trained on random-ratio schedules showed higher response rates and dramatically shorter pauses after rewards. Tests of addiction-like behavior, however, were largely negative. Response rates were not different during cued no-reward periods nor when reward was coupled with punishment. We also found no group differences when food was devalued nor in reinstatement of reward-seeking after a 1-week delay. The sole exception to this pattern was that rats in the second experiment showed greater persistence on a progressive ratio test. After experiment two, subjects were also orally administered pramipexole, which caused increased perseveration during progressive ratio testing, especially in the random ratio group. While, it is possible that longer training or more appetitive rewards might have led to addiction-like behavior, our results, on the surface, suggest that random-ratio schedules are motivating but not addictive.

A Randomized Controlled Trial of Cash Incentives or Peer Support to Increase HCV Treatment for Persons With HIV Who Use Drugs: The CHAMPS Study

Background

Despite access to direct-acting antivirals, barriers to a hepatitis C virus (HCV) cure persist, especially among persons living with human immunodeficiency virus (HIV) (PLWH) who use drugs. Interventions such as peer mentors or cash incentives may improve the care continuum.

Methods

The CHAMPS (Chronic HepAtitis C Management to ImProve OutcomeS) study randomized 144 PLWH, recruited from an outpatient clinic, with substance use disorders into three treatment groups: usual care (UC) (n = 36), UC plus cash incentives (n = 54), and UC plus peer mentors (n = 54) to evaluate HCV treatment uptake and cure. All participants received 12-weeks of ledipasvir/sofosbuvir (LDV/SOF). Trained peer mentors had well-controlled HIV and HCV. Cash incentives were contingent on visit attendance (maximum $220). The primary endpoint was HCV treatment initiation; secondary endpoints included sustained virologic response (SVR) and HCV reinfection.

Results

The majority of participants were male (61%), Black (93%), and unemployed (85%). Depression and active drug and alcohol use were common. Overall, 110 of 144 (76%) participants initiated LDV/SOF. Although treatment initiation rates were higher in PLWH randomized to peers (83%, 45 of 54) or cash (76%, 41 of 54) compared to UC (67%, 24 of 36), these differences were not statistically significant (P = .11). Most PLWH who initiated treatment achieved SVR (100 of 110, 91%). LDV/SOF was well tolerated; peers and cash had no effect on drug and alcohol use during therapy. One individual from the cash cohort experienced HCV reinfection.

Conclusion

After removal of system barriers, one-third of PLWH in UC did not initiate HCV treatment. Among those who initiated, SVR rates were high. Research involving PLWH who use drugs should focus on overcoming barriers to treatment initiation.

Clinical trial information

The registration data for the trial are in the ClinicalTrials.gov database, number NCT02402218.

Review of the effects of self-stigma and perceived social stigma on the treatment-seeking decisions of individuals with drug- and alcohol-use disorders

Substance-use disorders are a public health crisis globally and carry with them significant morbidity and mortality. Stigma toward people who abuse these substances, as well as the internalization of that stigma by substance users, is widespread. In this review, we synthesized the available evidence for the role of perceived social stigma and self-stigma in people’s willingness to seek treatment. While stigma may be frequently cited as a barrier to treatment in some samples, the degree of its impact on decision-making regarding treatment varied widely. More research needs to be done to standardize the definition and measurement of self- and perceived social stigma to fully determine the magnitude of their effect on treatment-seeking decisions.

Growth, morphometrics, and nutrient content of farmed eastern oysters, Crassostrea virginica (Gmelin), in New Hampshire, USA

When harvested, oysters represent a removal from the ecosystem of nutrients such as nitrogen (N) and carbon (C). A number of factors potentially affect nutrient content, but a quantitative understanding across the geographic range of the eastern oysters is lacking. The present study was designed to quantify the relationships among various metrics of farmed eastern oysters near its northern geographic range focusing on nutrient content. Hatchery-reared oysters were deployed in polyethylene bags at six sites, and were measured on multiple occasions from 2010-2012. A quadratic polynomial fit to the combined datasets for shell height indicated that on average a 'cocktail' size oyster (63 mm shell height) would be reached after 2 yr, and 'regular' size (76 mm) would require 3 yr. There were significant differences in growth rates and oyster nutrient content among the sites; means for %N in soft tissue ranged from 6.9 to 8.6, and 0.07 to 0.18 in shell. Percent N in soft tissue and shell were highest at two sites at the mouths of rivers with elevated dissolved inorganic N concentrations in the water. Grand means (all sites, seasons and years combined) of soft tissue N and C for regular size oysters were 7.3% and 38.5%, respectively; and for shell N and C were 0.13% and 12.0%, respectively. Our study extends the range of data on nutrient content of the eastern oyster to northern New England, and indicates that oyster size, seasonality, and nutrient concentration in ambient water potentially affect %N and %C content of oysters.

Wilt, Crown, and Root Rot of Common Rose Mallow (Hibiscus moscheutos) Caused by a Novel Fusarium sp

A new crown and root rot disease of landscape plantings of the malvaceous ornamental common rose mallow (Hibiscus moscheutos) was first detected in Washington State in 2012. The main objectives of this study were to complete Koch's postulates, document the disease symptoms photographically, and identify the causal agent using multilocus molecular phylogenetics. Results of the pathogenicity experiments demonstrated that the Fusarium sp. could induce vascular wilt and root and crown rot symptoms on H. moscheutos 'Luna Rose'. Maximum-likelihood and maximum-parsimony phylogenetic analyses of portions of translation elongation factor 1-α and DNA-directed RNA polymerase II largest and second-largest subunit indicated that the Hibiscus pathogen represents a novel, undescribed Fusarium sp. nested within the Fusarium buharicum species complex.

A bioactive probe for glutathione-dependent antioxidant capacity in breast cancer patients: implications in measuring biological effects of arsenic compounds

INTRODUCTION

Glutathione, a major cellular non-protein thiol (NPSH), serves a central role in repairing damage induced by cancer drugs, pollutants and radiation and in the detoxification of several cancer chemotherapeutic drugs and toxins. Current methods measure glutathione levels only, which require cellular extraction, rather than the glutathione recycling dependent antioxidant activity in intact cells. Here, we present a novel method using a bioactive probe of the oxidative pentose phosphate cycle, termed the OxPhos™ test, to quantify glutathione recycling dependent antioxidant activity in whole blood and intact human and rodent cells without the need for the isolation and cytoplasm extraction of cells.

METHODS

OxPhos™ test kit (Rockland Immunochemicals, USA), which uses hydroxyethyldisulfide (HEDS) as a probe for the oxidative pentose phosphate cycle, was used in these studies. The results with OxPhos™ test kit in human blood and intact cells were compared with total thiol and high pressure liquid chromatography/electrochemical detection of HEDS metabolism.

RESULTS

The OxPhos™ test measured glutathione-dependent antioxidant activity both in intact human and rodent cells and breast cancer patient's blood with a better correlation coefficient and biological variability than the thiol assay. Additionally, human blood and mammalian cells treated with various arsenicals showed a concentration-dependent decrease in activity.

DISCUSSION

The results demonstrate the application of this test for measuring the antioxidant capacity of blood and the effects of environmental pollutants/toxins. It opens up new avenues for an easy and reliable assessment of glutathione-dependent antioxidant capacity in various diseases such as stroke, blood borne diseases, infection, cardiovascular disease and other oxidative stress related diseases and as a prognostic indicator of chemotherapy response and toxicity. The use of this approach in pharmacology/toxicology including screening drugs that improve the glutathione-dependent antioxidant capacity and not just the glutathione level is clinically relevant since mammalian cells require glutathione dependent pathways for antioxidant activity.

A bioactive probe of the oxidative pentose phosphate cycle: novel strategy to reverse radioresistance in glucose deprived human colon cancer cells

The specific effects of glucose deprivation on oxidative pentose phosphate cycle (OPPC) function, thiol homeostasis, protein function and cell survival remain unclear due to lack of a glucose-sensitive chemical probe. Using p53 wild type and mutant human colon cells, we determined the effects of hydroxyethyl disulfide (HEDS) on NADPH, GSH, GSSG, total glutathione, total non-protein and protein thiol levels, the function of the DNA repair protein Ku, and the susceptibility to radiation-induced free radicals under normal glucose or glucose-deprived conditions. HEDS is rapidly detoxified in normal glucose but triggered a p53-independent metabolic stress in glucose depleted state that caused loss of NADPH, protein and non-protein thiol homeostasis and Ku function, and enhanced sensitivity of both p53 wild type and mutant cells to radiation induced oxidative stress. Additionally, high concentration of HEDS alone induced cell death in p53 wild type cells without significant effect on p53 mutant cells. HEDS offers a useful tool to gain insights into how glucose metabolism affects OPPC dependent stress-induced cellular functions and injury, including in tumor cells, where our findings imply a novel therapeutic approach to target glucose deprived tumor. Our work introduces a novel probe to address cancer metabolism and ischemic pathology.

Hydroxyethyl disulfide as an efficient metabolic assay for cell viability in vitro

Cell viability assays have a variety of well known practical and technical limitations. All the available approaches have disadvantages, such as non-linearity, high background and cumbersome protocols. Several commonly used tetrazolium chemicals rely upon generation of a colored formazan product formed by mitochondrial reduction of these compounds via phenazine methosulfate (PMS). However, sensitivity is inherently limited because their reduction relies on mitochondrial bioreduction and cellular transport of PMS, as well as accessibility to tetrazolium chemicals. In this study, we identify hydroxethyldisulfide (HEDS) as an inexpensive probe that can measure cellular metabolic activity without the need of PMS. In tissue culture medium, HEDS accurately quantitated metabolically active live cells in a linear manner superior to tetrazolium based and other assays. Cell toxicity produced by chemotherapeutics (cisplatin, etoposide), oxidants (hydrogen peroxide, acetaminophen), toxins (phenyl arsine oxide, arsenite) or ionizing radiation was rapidly determined by the HEDS assay. We found that HEDS was superior to other commonly used assays for cell viability determinations in its solubility, membrane permeability, and intracellular conversion to a metabolic reporter that is readily transported into the extracellular medium. Our findings establish the use of HEDS in a simple, rapid and low cost assay to accurately quantify viable cells.

Abstract 1392: HEDS selectively radiosensitizes human cancer cells in glucose-deprived environments via inhibition of Ku protein function

There remains great interest in strategies to increase the efficacy of radiation therapy in cancer patients. Glucose depletion occurs commonly in certain regions of bulky solid tumors, owing to high glucose metabolism combined with poor perfusion caused by a disorganized blood vasculature. Evidence suggests that cancer cells located in glucose-deprived regions are resistant to therapeutic killing. Agents that sensitize glucose-deprived cancer cells might offer useful adjuvants for tumor radiotherapy. In an earlier study, we demonstrated that rodent cells which are genetically deficient in the oxidative pentose phosphate cycle (OPPC) display a heightened response to hydroxyethyldisulfide (HEDS), a thiol-specific oxidant that can radiosensitize cells by blocking the redox-dependent function of DNA repair protein Ku. Since glucose is the chief substrate of the OPPC, and the OPPC is responsible for detoxifying HEDS, we reasoned that glucose deprivation should phenocopy the effects of OPPC deficiency in enhancing radiosensitization by HEDS. To test this prediction, we compared the effects of HEDS treatment in human colon cancer cell lines HCT116 or HT29, which are radiation sensitive or resistant, respectively. In both cell lines, HEDS was detoxified by OPPC-mediated conversion to mercaptoethanol (ME) in high-glucose media but not in low-glucose media. Consistent with the decrease in cellular bioreductant activity by glucose depletion, HEDS greatly decreased free glutathione levels under low-glucose conditions. Similarly, HEDS greatly decreased the free thiol content of total proteins and impaired the Ku DNA binding activity in low-glucose conditions. Most significantly, in clonogenic cell growth assay, the cytotoxic effects of HEDS were greatly increased under low glucose conditions, when added by itself to HCT116 cells but particularly when added in combination with irradiation to HCT116 or HT29 cells. Together, our findings indicate that glucose depletion enhances the ability of HEDS to radiosensitize cancer cells. More broadly, our findings suggest the potential to use HEDS in a novel strategy to enhance killing of radioresistant regions of tumors that are characterized by a glucose-depleted state.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1392.

Glucose deprivation increases nuclear DNA repair protein Ku and resistance to radiation induced oxidative stress in human cancer cells

Recent studies have indicated that nutrient deprivation particularly glucose may play a major role in tumor cell tolerance to a generally oxidative stress environment in solid tumors. Here, we studied the impact of glucose deprivation on the response of human colon (HT29) and prostate (DU145) cancer cells to gamma radiation. A significant decrease in intracellular glucose level was observed in glucose deprived cells as measured by bioreductive assay. The survival of HT29 and DU145 were increased by 30 and 100% respectively when these cells were exposed to gamma radiation in the absence of glucose compared to that in the presence of glucose. In glucose depleted medium, glutathione (GSH), a free radical scavenger, content remained the same, and showed no correlation with the radiation resistance induced by glucose deprivation. Glucose regulated protein78 (GRP78), a stress response survival protein, was not significantly increased in cells deprived of glucose for 4 h compared to those cells in glucose. DNA repair protein Ku, which is known to play a major role in cellular resistance to radiation, was significantly increased in glucose deprived cancer cells that showed enhanced radiation resistance. These results have demonstrated, for the first time, that glucose deprivation mediated stress increased the expression of nuclear Ku and resistance to radiation induced oxidative stress in human cancer cells. The additional resistance caused by glucose deprivation in cancer cells has clinical significance since solid tumors are known to have low level of glucose due to diffusion limited blood supply and higher metabolic activity.

Evaluation of germline CDKN2A, ARF, CDK4, PTEN, and BRAF alterations in atypical mole syndrome

Atypical mole syndrome is a sporadic or an inherited condition with an increased risk of melanoma. Germline mutations in the CDKN2A, ARF, CDK4 and somatic mutations in the PTEN and BRAF genes have been associated with melanoma. In this study, we evaluated genes associated with familial and sporadic melanoma for mutations in 28 probands with the atypical mole syndrome. No sequence alterations in the coding regions or in the splice junctions of CDKN2A, ARF, CDK4, PTEN or BRAF were identified. These data suggest that genes evaluated in this study are unlikely to be candidate genes for atypical mole syndrome and support the notion that unknown susceptibility gene/s for this disease exist.

Identification of a recurrent mutation in keratin 6a in a patient with overlapping clinical features of pachyonychia congenita types 1 and 2

Pachyonychia congenita is characterized by hypertrophic nail dystrophy and associated ectodermal features. PC-1 subtype is associated with mutations in keratins 6a or 16, whereas PC-2 subtype is linked to mutations in keratins 6b or 17. The correlation between the mutated gene and the type of PC has generally been consistent. In this report, we describe a case with overlapping clinical features of PC-1 and PC-2 in which a mutation in K6a was identified.

A near-fatal hypersensitivity reaction to abacavir: case report and literature review

A near-fatal hypersensitivity reaction to abacavir developed in a 62-year-old HIV-seropositive man who had been sensitized 17 months before presentation. Six days after he was rechallenged, acute respiratory distress developed, requiring mechanical ventilation for 2 weeks. Four days after extubation, he was again rechallenged. Hours later, the patient experienced anaphylactic shock, requiring mechanical ventilation for 3 weeks, aggressive volume resuscitation, and vasopressor support. Recovery was complicated by acute tubular necrosis, digital necrosis, and a GI bleed. This report reviews the mechanisms of action, efficacy, and adverse reactions of abacavir and illustrates the danger of serially rechallenging patients with this agent.

Community services, issues, and service gaps for individuals with developmental disabilities who exhibit inappropriate sexual behaviors

Inappropriate sexual behaviors represent the most challenging behaviors for community service providers. A national survey of 243 community agencies was conducted to describe services provided for individuals with developmental disabilities who exhibit high-risk sexual behaviors and to identify issues and service gaps. The most common types of offenses were sexual behavior (a) in public situations, (b) that inappropriately involved others, and (c) involved minors. Community agencies used multifaceted approaches to serve these individuals. The major issues and problems were systemic, specifically staff issues and service gaps, followed by funding. Implications of this study are that increased knowledge and skills related to sexuality and inappropriate sexual behavior and mental health resources are needed to build community capacity to serve this population.

High-Resolution Fourier Transform and Diode-Laser Spectroscopy of the nu(6) Fundamental of C(2)F(6) and Associated Hot Bands

High-resolution infrared spectra of the nu(6) (713 cm(-1)) band region of C(2)F(6) vapor have been recorded at several temperatures. Spectra at 77, 200, and 300 K were recorded using a Fourier transform spectrometer with unapodized resolutions of 0.0018 cm(-1) (200 and 300 K) and 0.008 cm(-1) (77 K). Spectra with rotational temperatures in the range 5-50 K were recorded in a supersonic jet using diode-laser absorption spectroscopy. The nu(6) band contains two clear sequences of hot-bands: one arises from the nu(4) torsional vibration at 67.5 cm(-1); the other, shorter, weaker progression is built on the doubly degenerate nu(9) vibration at 220 cm(-1). They lie to high and low wavenumbers of the fundamental band, respectively. Eleven series were assigned and fitted to these hot bands. A perturbed series in the nu(4) sequence is considered, by analogy with the infrared spectrum of C(2)H(6) vapor, to be caused by an xy-Coriolis interaction either between 5nu(4) and nu(9) + 2nu(4) in the ground state or, in the upper state, nu(6) + 5nu(4) with nu(6) + nu(9) + 2nu(4) or nu(6) + 5nu(4) with 2nu(8). One further series resolved only in the jet spectrum and lying very close to the fundamental is almost certainly due to the nu(6) fundamental of the isotopomer (13)C(12)CF(6). Copyright 2000 Academic Press.

Determination of pH using water protons and chemical exchange dependent saturation transfer (CEST)

Solution pH was measured using water proton NMR via chemical exchange dependent saturation transfer (CEST) with selected chemical exchange sites. Several useful pH-sensitive proton chemical exchange agents were found: 5,6-dihydrouracil, 5-hydroxytryptophan, and a combination of 5-hydroxytryptophan and 2-imidazolidinethione. A ratiometric approach was developed that permitted pH determinations that were independent of water T(1) or exchange site concentration.

A new class of contrast agents for MRI based on proton chemical exchange dependent saturation transfer (CEST)

It has been previously shown that intrinsic metabolites can be imaged based on their water proton exchange rates using saturation transfer techniques. The goal of this study was to identify an appropriate chemical exchange site that could be developed for use as an exogenous chemical exchange dependent saturation transfer (CEST) contrast agent under physiological conditions. These agents would function by reducing the water proton signal through a chemical exchange site on the agent via saturation transfer. The ideal chemical exchange site would have a large chemical shift from water. This permits a high exchange rate without approaching the fast exchange limit at physiological pH (6.5-7.6) and temperature (37 degrees C), as well as minimizing problems associated with magnetic field susceptibility. Numerous candidate chemicals (amino acids, sugars, nucleotides, heterocyclic ring chemicals) were evaluated in this preliminary study. Of these, barbituric acid and 5, 6-dihydrouracil were more fully characterized with regard to pH, temperature, and concentration CEST effects. The best chemical exchange site found was the 5.33-ppm indole ring -NH site of 5-hydroxytryptophan. These data demonstrate that a CEST-based exogenous contrast agent for MRI is feasible.

University-community partnerships for health: a model interdisciplinary service-learning project

This project is an example of a successful service-learning experiment at a major university. The program was successful in providing service-learning experiences for an interdisciplinary group of health-professions students, delivering essential health services to a community at risk, providing health-risk and demographic data, and offering opportunities for scholarly productivity for faculty. This was accomplished with a modest investment of internal start-up funding. Goals of the project were achieved, and the program and course were viewed as successful by students, faculty, and community partners.

Phosphorus nuclear magnetic resonance spectroscopy: in vivo magnesium measurements in the skeletal muscle of normal subjects

31P nuclear magnetic resonance spectroscopy was used to study the skeletal muscle of 33 normal males and 32 females. Free intracellular magnesium levels and the ratios of the phosphorus metabolites were determined. Males had significantly lower free magnesium levels (499.8 microM +/- 26.3 microM vs. 530.7 microM +/- 36.0 microM, P = 0.001, d.f. = 63, analysis of variance). The free magnesium level (rs = -0.5431, P = 0.001) and the phosphocreatin/Inorganic phosphate ratio in males (rs = -0.4102, P = 0.018), and the phosphocreatine/Inorganic phosphate ratio in females (rn = -0.4759, P = 0.009) fell with the increasing Minnesota Heart Health Program Questionnaire score.

Association between mild, routine exercise and improved insulin dynamics and glucose control in obese adolescents

The association between mild routine exercise and glucose homeostasis, insulin dynamics, and risk factors for coronary artery disease was investigated in obese adolescent males. Subjects (n = 7; mean +/- SD age 13.3 +/- 1.4 yr) were tested before and after 15 wk of supervised mild intensity exercise. Serum glucose (GLU), insulin (IN), and C-peptide (CP) were measured in response to a mixed meal before and after the 15 wk period. Weight, body composition, peak oxygen uptake (peak VO2), resting blood pressure (BP), and blood lipid levels were also assessed pre- and post-training. After training, percent fat and body weight were not decreased compared to the initial values. Relative changes (p < or = 0.02) in mean values for GLU and peptides after training were: fasting GLU, -15%; total GLU response, -15%; peak IN response, -51%; total IN response, -46%; peak CP response, +55%; and total CP response, +53%. Following training, the subjects did not have an increased peak VO2, but showed consistent reductions in systolic BP and LDL-cholesterol (p < 0.05). Increases in hepatic insulin clearance (decreased insulin levels but increased CP levels) might be training adaptations unique to low intensity exercise or to obese youth. Decreased insulin levels with concurrent decreases in resting blood pressure and the LDL-cholesterol levels suggest that mild exercise training may reduce health risk factors without weight loss in the obese adolescent male.

Diabetic nephropathy in an aerobically trained rat model of diabetes

The purpose of this study was to determine the effects of aerobic training on indices of glycemic control, blood pressure, serum lipids, and diabetic nephropathy (DN) in an animal model of insulin deficient diabetes mellitus. Thirty-four male Sprague-Dawley rats made diabetic with streptozocin were randomly assigned to a trained group or a sedentary group. Fifteen sedentary-nondiabetic rats served as a control group. The animals were trained on a treadmill at 18 m.min-1, 8 degrees incline for 120 min.d-1, 5 d.wk-1. Blood and 24 h urine collections were obtained at various intervals throughout the study. At 21 wk of age systolic blood pressure was measured and kidney tissue was obtained for light and electron microscopy. Analysis of variance was used to detect differences among the groups (P < or = 0.05). The diabetes produced in this investigation resulted in hyperglycemia, increased urine albumin and total protein excretion, elevated systolic blood pressure, increased fractional volume of the mesangium, and widening of the glomerular basement membrane in the sedentary-diabetic animals. Aerobic training significantly reduced the increase in fractional volume of the mesangium and fructosamine. Most importantly, aerobic training did not augment the renal damage seen in DN.

Clozapine is a potent and selective muscarinic M4 receptor agonist

Clozapine was studied in functional assays at human muscarinic M1-M5 receptors expressed in Chinese hamster ovary cells. Clozapine was a full agonist at the muscarinic M4 receptor (EC50 = 11 nM), producing inhibition of forskolin-stimulated cAMP accumulation. In contrast, clozapine potently antagonized agonist-induced responses at the other four muscarinic receptor subtypes. Selective stimulation of M4 receptors may, in part, explain the hypersalivation observed clinically with clozapine. Moreover, the unique overall muscarinic profile of clozapine may contribute to its atypical antipsychotic efficacy.

Aerobic training and diabetic nephropathy in the obese Zucker rat

The effects of aerobic exercise training on diabetes control and the development of renal microvascular disease were studied in the obese Zucker rat, an animal model of noninsulin dependent diabetes mellitus (NIDDM). Training consisted of 12 weeks of treadmill running, beginning at six weeks of age. Eight trained obese Zucker rats were compared to 15 obese sedentary controls and to 22 sedentary lean nondiseased littermates. Fasting blood glucose, percent of glycated hemoglobin, serum insulin, serum total cholesterol, body weight and kidney weight, creatinine clearance, urine total protein excretion, urine albumin excretion, and morphometric analyses of cortical glomeruli by light and electron microscopy were performed to evaluate metabolic control, renal function, and structure. Training was associated with less albuminuria, less mesangial volume expansion, and less glomerular basement membrane thickening compared to obese sedentary NIDDM animals. These results suggest that exercise training reduces the glomerular ultrastructural lesions and attenuates the albumin excretion rate in this rat model of obesity-related diabetes.

Modulation of dopamine binding in the fetal rat: effects of milk and exogenous opioid manipulation

Presentation of milk to the newborn rat promotes changes in sensory and motor behavior and concomitant changes in both endogenous opioid and dopamine systems. The present study employed an in vivo binding technique with a tritiated ligand for the D2 receptor ([3H]raclopride) to examine the effects of intraoral milk infusion and opioid manipulations on dopamine activity in the term rat fetus (E21). In Experiment 1, fetuses received a series of milk infusion, which resulted in decreased occupancy at D2 receptors by the endogenous ligand, dopamine, in striatal, septal, and hypothalamic brain regions. In Experiment 2, fetuses were pretreated with morphine, the mu-agonist [D-Ala2,NMe-Phe4,Gly5-ol]-enkephalin (DAMGO), the kappa-agonist U50,488, or saline. Opioid manipulations had no effect on binding at D2 receptors. These results confirm that intraoral milk infusion can modulate activity in the dopamine system of the near-term fetal rat.

Use of blood glucose data by families of children and adolescents with IDDM

OBJECTIVE

Prospective evaluation of the use of blood glucose test results for treatment actions by families of youth with IDDM.

RESEARCH DESIGN AND METHODS

Forty-seven patients with IDDM used reflectance meters with memory for SMBG for 28 days. Parents kept weekly diaries of six types of uses of SMBG data. We collected SMBG data from the reflectance meters, HbA1 and serum fructosamine assays, and measures of behavioral factors that could affect use of SMBG data.

RESULTS

Families recorded a mean of 4.85 data-based actions during the 28-day study, and 74% of the families reported at least one such action. Fifty percent of recorded actions consisted of management of hypoglycemia and, among the remainder, only 18% were anticipatory, proactive actions. Partial correlation analysis showed that families with more frequent use of SMBG data had less parent-child conflict about diabetes, more diabetes knowledge, and better overall treatment adherence. Use of SMBG data was unrelated to objective indices of the need for treatment adjustments or to diabetic control.

CONCLUSIONS

Most families made active use of their SMBG data, but few of these actions were proactive. Behavioral factors were stronger predictors of family use of SMBG data than were objective indices of the need for treatment adjustments. The results illustrate the need for further research on use of SMBG data and methods to enhance its impact on diabetic control.

Diabetes mellitus in the transition to adulthood: adjustment, self-care, and health status

A cross-sectional study of health and adjustment among 18 to 22-year-old patients with insulin-dependent diabetes mellitus (IDDM) is reported. Objectives were to examine coping with IDDM in this age group; to identify predictors of health status, treatment adherence, and health care use; and to provide a retrospective evaluation of the persistence of IDDM-specific adjustment from earlier through later adolescence. Multiple validated measures, interviews of independent informants, and biochemical assays were used to assess psychological, behavioral, and metabolic status. Patients and parents completed a retrospective measure of the patient's adjustment to IDDM during earlier adolescence. Findings (n = 81) indicated: (1) normal rates of general psychopathology but some evidence of poorer adjustment to IDDM relative to other age groups, (2) poor diabetic control and high incidence of microalbuminuria, (3) specific factors associated differentially with treatment compliance, health care use, diabetic control, and microalbuminuria among late adolescents, and (4) evidence that poor adjustment to IDDM in earlier adolescence persists into the transition to adulthood. The findings imply that late adolescents with IDDM are at risk of various unfavorable behavioral and health outcomes and that adjustment to the disease during earlier adolescence may be a predictor of subsequent health-related behavior and health status. A longitudinal study is needed to confirm these findings.

Current concepts in proteinuria

Proteinuria, long recognized as a sign of renal disease, is a common laboratory abnormality in children and adults. Proteinuria may be transient or persistent; when persistent, the cause must be determined. Proteinuria may be primarily glomerular or tubular in origin. Glomerular proteinuria is usually an important concern. Tubular proteinuria often indicates the presence of tubulointerstitial or obstructive renal disease. Screening tests are available to detect albumin (the major protein in glomerular proteinuria), but there are no simple tests for immunoglobulin light chains and low-molecular-mass proteins, which predominate in overflow proteinuria and tubular proteinuria. These small proteins can only be detected by more sophisticated assays such as electrophoresis, isoelectric focusing, and chromatography. The association of glomerular and tubular types of proteinuria with specific disorders is reviewed in this paper, and current concepts in laboratory methodology for the study of proteinuria are summarized.

Current concepts in proteinuria

Proteinuria, long recognized as a sign of renal disease, is a common laboratory abnormality in children and adults. Proteinuria may be transient or persistent; when persistent, the cause must be determined. Proteinuria may be primarily glomerular or tubular in origin. Glomerular proteinuria is usually an important concern. Tubular proteinuria often indicates the presence of tubulointerstitial or obstructive renal disease. Screening tests are available to detect albumin (the major protein in glomerular proteinuria), but there are no simple tests for immunoglobulin light chains and low-molecular-mass proteins, which predominate in overflow proteinuria and tubular proteinuria. These small proteins can only be detected by more sophisticated assays such as electrophoresis, isoelectric focusing, and chromatography. The association of glomerular and tubular types of proteinuria with specific disorders is reviewed in this paper, and current concepts in laboratory methodology for the study of proteinuria are summarized.

Effects of denervation and immobilisation during development upon [3H]ouabain binding by slow- and fast-twitch muscle of the rat

The effect of innervation and of muscle inactivity upon the normal production of Na+-K+-ATPase sites, assayed by [3H]ouabain binding, in muscle surface membranes has been determined for the rat. In both slow-twitch soleus (SOL) and fast-twitch extensor digitorum longus (EDL) muscles a large increase was found to occur in [3H]ouabain binding per unit weight of muscle over the first 3 weeks of life. Interruptions of development, brought about by fixation of muscles at different lengths at 5 days of age, had no significant effect upon [3H]ouabain binding by EDL. In contrast, fixation led to a decrease in binding in SOL. When fixed in a shortened position profound morphological changes occurred, although these were not apparent when SOL was fixed in a stretched position. Denervation of SOL at 5 days of age significantly reduced the age related increase in the density of [3H]ouabain binding, whilst denervation of EDL had little effect. It was concluded that normal development of SOL is dependent upon innervation and possibly the resulting muscle activity, whereas development of EDL was relatively independent of innervation.

Membrane potential and intracellular potassium and sodium activities after denervation of soleus muscles of neonatal rats

Potassium and sodium ion-selective microelectrodes were used in vitro to investigate the depolarization of slow-twitch skeletal muscle fibers (soleus) following denervation at 5 to 6 days of age. The normal increase in intracellular potassium ion activity and decrease in sodium ion activity which occurs during the first 3 weeks of life were delayed or prevented by denervation. The results are compared with those found after similar periods of denervation of neonatal rat fast-twitch muscle.

Effect of denervation during development upon membrane potential and intracellular potassium and sodium activities of skeletal muscle of the rat

Potassium and sodium ion-selective microelectrodes were used in vitro to investigate the effect of denervation of fast-twitch skeletal muscle (extensor digitorum longus) at 5 days of age upon subsequent development of the resting membrane potential. Normally, during the first 3 weeks of life the balance of intracellular potassium and sodium changed to elevate potassium and to lower sodium. These changes were reflected in the development of a more hyperpolarized resting membrane. Periods of denervation delayed, or prevented, the changes in ion activities and membrane hyperpolarization from occurring. The results are compared with those found after denervation of adult skeletal muscle.

Effects of POCA on metabolism and function in the ischemic rat heart

Sodium 2-[5-(4-chlorophenyl)-pentyl]-oxirane-2-carboxylate (POCA) inhibits carnitine palmityltransferase I and fatty acid oxidation. The effects of POCA on cardiac function and on tissue levels of carnitine and coenzyme A esters were studied in the isolated rat heart subjected to 90 minutes of ischemia with and without 15 minutes of reperfusion. The perfusion medium contained 1.2 mM palmitate and 5.5 mM glucose plus or minus 0.5 mM POCA. This compound prevented accumulation of long-chain acylcarnitine and coenzyme A esters during ischemia and significantly improved the recovery of cardiac output after ischemia and reperfusion. Short-chain acylcarnitine levels were increased during ischemia by POCA. No effects were noted on tissue ATP and lactate levels. POCA may protect the ischemic heart by preventing accumulation of these toxic metabolites and by stimulating glucose utilization during ischemia.

Changes in membrane potential and potassium and sodium activities during postnatal development of mouse skeletal muscle

Dual-channel potassium-selective and single-channel sodium-selective microelectrodes were used to investigate the cause of changes in resting membrane potential of muscle fibers of the mouse during early development. The resting membrane of extensor digitorum longus fibers hyperpolarized during the postnatal period from -41.8 mV at 4 days of age to -76.4 mV at 27 days. During this period intracellular potassium activity increased by 42.1% from 82.5 mM at 8 days to 117.2 mM at 29 days. Intracellular sodium activity was high at 8 days, 23.7 mM, but decreased rapidly to adult values by 27 days when it was 9.98 mM, a 57.9% reduction in sodium activity. The time course of the change in resting membrane potential was different from that of the potassium equilibrium potential calculated from the data. If only potassium and sodium ions were to make significant contributions to the potential, then it was calculated that the permeability ratio PNa:PK would have to change from a value of 0.0659 at 8 days to 0.0227 at 27 days. The results indicated that other factors might be involved in generating the membrane potential inasmuch as, although both intracellular potassium and sodium activities did not change significantly after 27 to 30 days, the membrane potential had not attained adult values at that time. The possibility that increases in muscle activity during the postnatal period might initiate the changes in membrane polarization and intracellular ion activities is discussed together with possible complications in interpretation due to great variations in fiber diameters.

[3H]Ouabain binding in normal and dystrophic mouse skeletal muscles and the effect of age

The numbers of Na+-K+ ATPase sites in skeletal muscles of normal and dystrophic mice between 3 and 17 months of age have been estimated using [3H]ouabain binding assays. In normal mice, at all ages, slow twitch muscle, soleus (SOL), bound significantly more [3H]ouabain than fast-twitch muscle, extensor digitorum longus (EDL). [3H]Ouabain binding did not alter in either SOL or EDL from normal mice over the age range studied. The numbers of Na+-K+ ATPase sites did alter in muscles taken from dystrophic mice (C57BL/6J dy2J/dy2J). In EDL there was an increase and in SOL a decrease in [3H]ouabain binding. This may be related to a change in muscle fibre metabolism from glycolytic to oxidative or to an altered activity pattern. Increasing age resulted in a progressive reduction in [3H]ouabain binding of both SOL and EDL from dystrophic mice. Part of this reduction may be only apparent and due to an increase in connective tissue composition of dystrophic muscles. A limited study of muscles from neonate dystrophic mice indicated that abnormal [3H]ouabain binding was not present in EDL before two weeks of age.

Malonyl CoA inhibition of carnitine palmityltransferase in rat heart mitochondria

The effects of malonyl CoA on carnitine palmityltransferase I (CPT-I), fatty acid-supported state 3 respiration, and carnitine reversal of palmityl CoA inhibition of state 3 respiration and of the adenine nucleotide translocator, were studied in isolated rat heart mitochondria. Malonyl CoA was a potent competitive inhibitor of CPT-I with an I50 of 0.8 microM. Fasting did not affect CPT-I activity or the I50 value of malonyl CoA. Malonyl CoA inhibited fatty acid-supported respiration and prevented carnitine from reversing the inhibition of the adenine nucleotide translocator by palmityl CoA. These findings suggest that malonyl CoA may affect fatty acid oxidation in the heart.

Intracellular activity of sodium in normal and dystrophic skeletal muscle from C57BL/6J mice

Potassium and sodium ion-selective microelectrodes were used in vitro to investigate the depolarization of skeletal muscle fibers associated with muscular dystrophy. In dystrophy there was a large increase of intracellular Na activity and an associated decrease in K activity in fibers of extensor digitorum longus muscles. Despite this, the recorded membrane potential was very close to the calculated potassium equilibrium potential (Ek) in dystrophic fibers. In contrast, in normal muscle fibers, Em was significantly depolarized with respect to Ek. The data suggest that in dystrophic fibers there is an increase in the relative membrane permeability to potassium over sodium.

Effects of slow frequency electrical stimulation on muscles of dystrophic mice

The hind leg muscles of dystrophic mice (C57 BL dy2J/dy2J) wer chronically stimulated at 10 Hz for 30 minutes six times a day. After 14 days of such activity a clinical improvement in the use of the stimulated leg was noticed. The twitch and tetanic tensions developed by the stimulated tibialis anterior and extensor digitorum longus muscles were higher than those developed by the control, unstimulated muscles on the contralateral side. Histochemically visualised activity of the oxidative enzyme succinic dehydrogenase was greater in fibres of the stimulated muscles. The stimulated muscles contained more muscle fibres than unstimulated controls. It is concluded that slow frequency activity has a beneficial effect on muscles of dystrophic mice.

Neomycin ototoxicity

A case of oral neomycin ototoxicity is presented, followed by a summary of known cases in the English literature. While it is known that neomycin is concentrated in the inner ear fluids, at the present time the biochemical basis of its ototoxic effect has not been definitively elucidated. High frequency audiometry can aid in the early detection of the onset of neomycin-induced deafness. Dialysis has a limited but useful role in preventing neomycin ototoxicity.

Epiglottic abscess: its occurrence and management

Twenty-six cases of epiglottic abscess from the English literature are reviewed. The condition occurs nearly exclusively in adults and it has a high mortality rate (30 per cent). The lingual surface of the epiglottis is most commonly involved and less than half of the patients present with severe airway obstruction. The management of the condition is dictated by the degree of airway obstruction.