Cysteine S-acetylation is a post-translational modification involved in metabolic regulation.

Cysteine is a reactive amino acid central to the catalytic activities of many enzymes. It is also a common target of post-translational modifications (PTMs), such as palmitoylation. This longchain acyl PTM can modify cysteine residues and induce changes in protein subcellular localization. We hypothesized that cysteine could also be modified by short-chain acyl groups, such as cysteine S-acetylation. To test this, we developed sample preparation and non-targeted mass spectrometry protocols to analyze the mouse liver proteome for cysteine acetylation. Our findings revealed hundreds of sites of cysteine acetylation across multiple tissue types, revealing a previously uncharacterized cysteine acetylome. Cysteine acetylation shows a marked cytoplasmic subcellular localization signature, with tissue-specific acetylome patterns and specific changes upon metabolic stress. This study uncovers a novel aspect of cysteine biochemistry, highlighting short-chain modifications alongside known long-chain acyl PTMs. These findings enrich our understanding of the landscape of acyl modifications and suggest new research directions in enzyme activity regulation and cellular signaling in metabolism.

Studies of Thioamide Effects on Serine Protease Activity Enable Two-Site Stabilization of Cancer Imaging Peptides.

Thioamide substitutions in peptides can be used as fluorescence quenchers in protease sensors and as stabilizing modifications of hormone analogs. To guide these applications in the context of serine proteases, we here examine the cleavage of several model substrates, scanning a thioamide between the P3 and P3' positions, and identify perturbing positions for thioamide substitution. While all serine proteases tested were affected by P1 thioamidation, certain proteases were also significantly affected by other thioamide positions. We demonstrate how these findings can be applied by harnessing the combined P3/P1 effect of a single thioamide on kallikrein proteolysis to protect two key positions in a neuropeptide Y-based imaging probe, increasing its serum half-life to >24 h while maintaining potency for binding to Y1 receptor expressing cells. Such stabilized peptide probes could find application in imaging cell populations in animal models or even in clinical applications such as fluorescence-guided surgery.

Use of the Alcohol Use Disorders Identification Test (AUDIT) to determine the prevalence of alcohol misuse among HIV-infected individuals.

The aim of the paper is to evaluate alcohol misuse among an inner city adult HIV clinic population with AUDIT (Alcohol Use Disorders Identification Test). A cross-sectional HIV outpatient clinic analysis between 28 February 2011 and 11 March 2011 was carried out. AUDIT, demographic and clinical data were collected. Univariate analysis was performed to look for the associations between variables. Backward stepwise multivariate analyses were performed on significant variables from the univariate analysis to assess for predictors of alcohol dependence. In total, 111 patients were included (60% uptake of clinic attendees); 66% were men and 26% were hepatitis C virus (HCV) co-infected. The median AUDIT score was 5 (within normal range). Thirty-four 'AUDIT positive' cases were identified: five (4.5%) indicated consumption of hazardous levels of alcohol; 21 (19%) indicated harmful levels of alcohol; and eight (7%) were likely alcohol dependent. Younger age (<40 years old) was significantly associated with AUDIT positivity (P = 0.006). On multivariate analysis younger age (P = 0.045, odds ratio 13.8) and lower level of education (P = 0.006, odds ratio 6.7) were predictive of scores indicative of alcohol dependence (AUDIT ≥20). In conclusion, younger age and lower educational levels were associated with scores consistent with alcohol dependence. AUDIT was well tolerated and easy to administer in this outpatient HIV clinic population.

Peripherally inserted central catheter usage patterns and associated symptomatic upper extremity venous thrombosis.

OBJECTIVES: Peripherally inserted central catheters (PICCs) may be complicated by upper extremity (UE) superficial (SVT) or deep venous thrombosis (DVT). The purpose of this study was to determine current PICC insertion patterns and if any PICC or patient characteristics were associated with venous thrombotic complications. METHODS: All UE venous duplex scans during a 12-month period were reviewed, selecting patients with isolated SVT or DVT and PICCs placed ≤30 days. All UE PICC procedures during the same period were identified from an electronic medical record query. PICC-associated DVTs, categorized by insertion site, were compared with all first-time UE PICCs to determine the rate of UE DVT and isolated UE SVT. Technical and clinical variables in patients with PICC-associated UE DVT also were compared with 172 patients who received a PICC without developing DVT (univariable and multivariable analysis). RESULTS: We identified 219 isolated UE SVTs and 154 UE DVTs, with 2056 first-time UE PICCs placed during the same period. A PICC was associated with 44 of 219 (20%) isolated UE SVTs and 54 of 154 UE DVTs (35%). The rates of PICC-associated symptomatic UE SVT were 1.9% for basilic, 7.2% for cephalic, and 0% for brachial vein PICCs. The rates of PICC-associated symptomatic UE DVT were 3.1% for basilic, 2.2% for brachial, and 0% for cephalic vein PICCs (χ(2)P < .001). Univariate analysis of technical and patient variables demonstrated that larger PICC diameter, noncephalic insertion, smoking, concurrent malignancy, diabetes, and older age were associated with UE DVT (P < .05). Multivariable analysis showed larger catheter diameter and malignancy were the only variables associated with UE DVT (P < .05). CONCLUSIONS: The incidence of symptomatic PICC-associated UE DVT is low, but given the number of PICCs placed each year, they account for up to 35% of all diagnosed UE DVTs. Larger-diameter PICCs and malignancy increase the risk for DVT, and further studies are needed to evaluate the optimal vein of first choice for PICC insertion.

Alcohol screening and brief intervention among drug users in primary care: a discussion paper.

BACKGROUND: Problem alcohol use is common among problem drug users (PDU) and associated with adverse health outcomes. Primary care has an important role in the overall stepped approach to alcohol treatment, especially screening and brief intervention (SBI). AIM: To discuss three themes that emerged from an exploration of the literature on SBI for problem alcohol use in drug users attending primary care. METHODS: Material for this discussion paper was gathered from three biomedical databases (PubMed, PsycINFO and Cochrane library), conference proceedings and online resources of professional organisations or national health agencies. RESULTS: Themes discussed in this paper are: (a) the potential of primary care for delivery of alcohol SBIs to PDUs, (b) screening methods and (c) application of brief interventions to PDUs. CONCLUSIONS: Although SBI improves health outcomes associated with problem alcohol use in the general population, further research is needed among high-risk patient groups, especially PDUs.

HIV infection among heroin users and area of residence.

The aim of this study was to develop a hypothesis to explain the link between HIV prevalence and area of residence. The study was conducted in two parts using two existing data sources. In Part 1, the bloodborne viral test status and test results of a sample of clients attending treatment in December 2001 in two areas of Dublin, an inner city area (Dublin 8) and a suburban area (Dublin 24), were extracted from the Bloodborne Viral Status Dataset created by Grogan. In Part 2 the characteristics of heroin users seeking treatment for the first time at treatment services in their respective areas of residence, Dublin 8 or Dublin 24, between 1997 and 2000 were examined, using data from the National Drug Treatment Reporting System. A higher proportion of heroin users in Dublin 8 had HIV and hepatitis C than did their counterparts in Dublin 24. The analysis suggests that heroin users in Dublin 8 were more likely both to have ever used cocaine and to have used heroin daily, than were those who lived in Dublin 24. Also, a higher proportion of injectors living in Dublin 8 used heroin and cocaine concurrently than did their counterparts in Dublin 24. In both samples, heroin users who lived in Dublin 8 were older than those who lived in Dublin 24. The findings led to a hypothesis:'The risk of acquiring HIV is associated with area of residence and may be linked to cocaine use.

Epidemiological findings and medical, legal, and public health challenges of an investigation of severe soft tissue infections and deaths among injecting drug users -- Ireland, 2000.

In May 2000, public health authorities in Dublin, Ireland, identified a cluster of unexplained severe illness among injecting drug users (IDUs). Similar clusters were also reported in Scotland and England. Concurrent investigations were undertaken to identify the aetiology and source of the illnesses. In Dublin, 22 IDUs were identified with injection-site inflammation resulting in hospitalization or death; eight (36%) died. Common clinical findings among patients with severe systemic symptoms included leukaemoid reaction and cardiogenic shock. Seventeen (77%) patients reported injecting heroin intramuscularly in the 2 weeks before illness. Of 11 patients with adequate specimens available for testing, two (18%) were positive by 16S rDNA PCR for Clostridium novyi. Clinical and laboratory findings suggested that histotoxic Clostridia caused a subset of infections in these related clusters. Empiric treatment for infections among IDUs was optimized for anaerobic organisms, and outreach led to increased enrolment in methadone treatment in Dublin. Many unique legal, medical, and public health challenges were encountered during the investigation of this outbreak.

Bloodborne virus infections among drug users in Ireland: a retrospective cross-sectional survey of screening, prevalence, incidence and hepatitis B immunisation uptake.

BACKGROUND: Injecting drug users are at high-risk of bloodborne virus infections including hepatitis C (HCV), hepatitis B (HBV) and HIV. AIMS: To document screening for and immunisation against bloodborne viruses and to determine the known prevalence and incidence of these infections. METHODS: A cross-sectional survey of clients attending 21 specialist addiction treatment clinics in one health board area in greater Dublin. Data collected on demographic characteristics, serology for HCV, HBV and HIV and immunisation against HBV. RESULTS: A total of 316 (88%) had been tested for anti-HCV antibody, 244 (68%) had been tested for anti hepatitis B core antibody (anti-HBc), 299 (84%) had been tested for hepatitis B surface antigen (HBsAg) and 307 (86%) had been tested for anti-HIV antibody. The prevalence of anti-HCV, anti-HBc, HBsAg, and anti-HIV were: 66%, 17%, 2% and 11% respectively. The incidence of HCV, HBV and HIV infections were: 24.5, 9.0 and 3.4 per hundred person years respectively. Eighty-one per cent of those in whom it was indicated, had started a targeted HBV immunisation programme in the clinics. CONCLUSION: The proportion of clients screened for HCV, HBV and HIV infection has increased since the introduction of a screening protocol in 1998. Targeted vaccination for opiate users against hepatitis B is more successful than previously shown in Ireland. The prevalence and incidence of bloodborne viruses remains high among opiate users attending addiction treatment services, despite an increase in availability of harm reduction interventions.

Safety and efficacy of the use of bioabsorbable seamguard in colorectal surgery at the Texas endosurgery institute.

Bioabsorbable Seamguard (BSG) is a random-fiber web of polyglycolic acid/trimethylene carbonate. It is completely absorbed within 6 months or less due to its constitution of a bioabsorbable membrane with polyester braided suture. It has been used in obesity surgery and pulmonary surgery as staple-line reinforcement with good results. As such, we believe that BSG may be ideal to use in colorectal surgery as an aid during the healing process of an anastomosis and may help prevent anastomotic bleeding and staple-line disruption. From July 2003 through September 2004, 30 patients underwent placement of BSG for the following procedures: 12 right hemicolectomies, 7 low anterior resections, 5 sigmoid colectomies, 3 total colectomies, 2 partial resections, and 1 colostomy closure. Median follow-up was 7 months (range 1-13). There were no clinical leaks, no strictures, and no bleeding in our early postoperative follow-up period. The use of BSG as a staple-line reinforcer appears to be safe and may be useful in preventing anastomotic leakage, bleeding, and intraluminal stenosis.

Heroin smoking by "chasing the dragon" in young opiate users in Ireland: stability and associations with use to "come down" off "Ecstasy".

We explored the frequency of commencing opiate use by "chasing the dragon" to "come down" off Ecstasy and the stability of heroin smoking in young opiate takers by assessing 102 subjects in Dublin using a semistructured interview. Ninety-two subjects had used Ecstasy. Of these, 68 reported "chasing" to "come down" off Ecstasy at some point in their history and were found to have used Ecstasy more frequently and in larger amounts. Thirty-six reported that their first experience of using opiates was to "come down" off Ecstasy, 28 citing this as their main reason for commencement.Eighty-six of the 102 commenced opiates by "chasing" heroin, 61 of whom progressed to injecting after a mean of 2.9 years. This was associated with starting illicit drug use earlier, starting heroin earlier, and a history of using Ecstasy. Implications for service planners in developing responses to illicit drug use among adolescents are discussed.

Induction and concurrent paclitaxel/carboplatin every 3 weeks with thoracic radiotherapy in locally advanced non-small-cell lung cancer: an interim report.

The paclitaxel/carboplatin combination has demonstrated promising activity in metastatic non-small-cell lung cancer (NSCLC); therefore, we mounted an exploratory study of these agents with thoracic radiation (TRT) in locally advanced NSCLC. Eligibility stipulated a Karnofsky performance status >or= 70%, weight loss or= 2 esophagitis has corresponded to length (> 16 cm) of esophagus in the radiation treatment field (Fisher's exact test, P = 0.006). The partial response rate to induction therapy was 40% and to the combined modality therapy was 60%. The median survival for all 49 patients is 15.3 months, with a median disease-free survival (DFS) of 7.8 months. In the subset of 22 patients treated on the phase I portion of the study, the median survival and DFS were 18.5 months and 13.5 months, respectively. Induction therapy with paclitaxel and carboplatin followed by concurrent chemoradiotherapy with the same agents is an active and well-tolerated treatment approach in locally advanced NSCLC. To date, paclitaxel 175 mg/m2 plus carboplatin AUC 5 administered at 3-week intervals for 2 cycles is safe in combination with TRT.

Assessment of hepatitis C infection in injecting drug users attending an addiction treatment clinic.

BACKGROUND: Injecting drug users represent a high risk group for hepatitis C (HCV) infection. Currently, screening of this group for HCV is inconsistently implemented. AIM: We designed a HCV assessment algorithm and sought to determine the frequency with which injecting drug users completed the assessment process. METHODS: Prospective study of a HCV assessment algorithm in the setting of a specialist outpatient addiction treatment clinic. Participants consisted of consecutive new attenders over a six-month period with a history of injecting. RESULTS: Only 21 (18%) of 119 patients reached a satisfactory endpoint of assessment. Forty-eight injectors were tested for antibody to HCV, of whom 26 (54%) tested positive. Thirteen of those with positive test results were no longer attending when the test result became available. Only four of the 19 patients who were referred, attended the on-site hepatology clinic. CONCLUSIONS: Thorough screening of injecting drug users for HCV within one treatment service is difficult. There is a need for explicit policies on this issue involving co-operation between primary care providers and addiction services and hepatology services.

NH2-terminally truncated HER-2/neu protein: relationship with shedding of the extracellular domain and with prognostic factors in breast cancer.

We identified an NH2-terminally truncated HER-2/neu product of M(r) 95,000 with in vitro kinase activity by Western blotting and immunoprecipitations using domain-specific antibodies. p95 levels correlated with the extracellular domain (ECD) shed from different cells under varied conditions. Both ECD and p95 were at approximately 20-fold lower levels in SKOV3 ovarian carcinoma cells, as compared to BT474 breast carcinoma cells. Both were stimulated by treatment of cells with the phorbol ester tumor promoter phorbol 12-myristate 13-acetate and the lysosomotrophic agent chloroquine. The hydroxamate inhibitor of metalloproteases, TAPI, suppressed both p95 and ECD in a dose-dependent fashion, with maximal inhibition at < or = 10 microM in BT474 cells. Cancer tissues were analyzed by Western blotting and scored for p95HER-2/neu and for p185HER-2/neu expression. Breast and ovarian cancer tissues were both found to express p95HER-2/neu in addition to p185HER-2/neu. Of 161 breast cancer tissues, 22.4% expressed p95, 21.7% overexpressed p185, and 14.3% were p95 positive and overexpressed p185. A higher proportion of node-positive patients (23 of 78) than node-negative patients (9 of 63) expressed p95 in all tumors combined (P = 0.032). In the group that overexpressed p185, those that contained p95 were associated with node-positive patients (15 of 21), whereas those that were p95 negative were associated with node-negative patients (8 of 11; P = 0.017). Neither p95- nor p185-rich patients significantly correlated with tumor size or with hormone receptor status in this study. Our findings show that breast cancers, which express the HER-2/neu oncogene, are heterogeneous with respect to HER-2/neu protein products. p95HER-2/neu appears to distinguish tumors that have metastasized to the lymph nodes from those in node-negative patients.

Induction paclitaxel and carboplatin followed by concurrent chemoradiotherapy in patients with unresectable, locally advanced non-small cell lung carcinoma: report of Fox Chase Cancer Center study 94-001.

The paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ)/carboplatin combination has demonstrated promising activity in patients with incurable non-small cell lung cancer (NSCLC). Our exploratory study is designed to evaluate the efficacy of this combination as induction therapy in patients with locally advanced NSCLC, to determine the maximally tolerated doses of paclitaxel and carboplatin administered every 3 weeks during radical thoracic radiation after induction treatment, and to determine the efficacy of granulocyte colony-stimulating factor (G-CSF) priming before induction treatment, followed by conventional G-CSF, compared with conventional G-CSF alone. Eligibility stipulated Karnofsky performance status > or =70%, < or =5% weight loss, and stages IIIB or bulky IIIA NSCLC. Induction treatment consisted of two cycles of paclitaxel 175 to 225 mg/m2 infused over 3 hours combined with carboplatin (target area under the concentration-time curve of 7.5) given on days 1 and 22. On days 2 through 15 and 23 through 36, all patients received G-CSF 5 microg/kg; half were randomized to receive priming G-CSF daily for 5 days before day 1 of treatment. On day 43, thoracic radiation (60 Gy in 30 2-Gy fractions daily, 5 days a week for 6 weeks) was initiated. At dose level 1, patients received carboplatin dosed to a target area under the concentration-time curve of 3.75 and paclitaxel 67.5 mg/m2 over 3 hours on days 43 and 64. In the absence of dose-limiting toxicity, phase I escalation in three-patient cohorts proceeded to a maximum carboplatin area under the concentration-time curve of 5.0 and a paclitaxel dose of 175 mg/m2, delivered over 3 hours. To date, 35 patients (83% stage IIIB) have received induction treatment, 29 of whom are evaluable for response. Myelosuppression and neurotoxicity have been mild during induction treatment, prompting a paclitaxel dose increase to 225 mg/m2 on days 1 and 22 after the first seven patients were accrued. The phase III portion of the study evaluating G-CSF priming remains coded. Sixteen patients have received concurrent thoracic radiation and chemotherapy and are evaluable for response and toxicity. In sequential cohorts, the paclitaxel dose on days 43 and 64 has been escalated to 175 mg/m2 with only one episode each of grade 4 granulocytopenia and grade 3 anemia. In the first 13 patients evaluated, the severity of esophagitis corresponded to the length of the esophagus in the radiation treatment field: grade 1 in all six patients with esophageal exposure < or =16 cm and grade > or =2 in six of seven patients with > or =16 cm of the esophagus irradiated. Three episodes of grade > or =2 steroid-responsive pulmonary toxicity have occurred 2 to 6 months after the conclusion of concurrent thoracic radiation and chemotherapy. The major response rate is 38% to induction treatment and 59% to combined-modality treatment. Of the first 21 patients accrued, 62% survived 1 year. Induction paclitaxel/carboplatin therapy is active and well tolerated by patients with locally advanced NSCLC. The maximum tolerated doses of paclitaxel and carboplatin during concurrent thoracic radiation and the role of G-CSF priming are not yet established. Severity of esophagitis corresponds to the extent of esophagus irradiated during concurrent thoracic radiotherapy and chemotherapy.

Transcriptional up-regulation of the human androgen receptor by androgen in bone cells.

Androgen regulation of androgen receptor (AR) expression has been observed in a variety of tissues, generally as inhibition, and is thought to attenuate cellular responses to androgen. AR is expressed in osteoblasts, the bone-forming cell, suggesting direct actions of androgens on bone. Here we characterized the effect of androgen exposure on AR gene expression in human osteoblastic SaOS-2 and U-2 OS cells. Treatment of osteoblastic cells with the nonaromatizable androgen 5alpha-dihydrotestosterone increased AR steady state messenger RNA levels in a time- and dose-dependent fashion. Reporter assays with 2.3 kilobases of the proximal 5'-flanking region of the human AR promoter linked to the chloramphenicol acetyltransferase gene in transfected cultures showed that up-regulation of AR promoter activity by androgen was time and dose dependent. Treatment with other steroid hormones, including progesterone, 17beta-estradiol, and dexamethasone, was without effect. The antiandrogen hydroxyflutamide completely antagonized androgen up-regulation. Thus, in contrast to many other androgen target tissues, androgen exposure increases steady state AR messenger RNA levels in osteoblasts. This regulation occurs at least partially at the level of transcription, is mediated by the 5'-promoter region of the AR gene, and is dependent on functional AR. These results suggest that physiological concentrations of androgens have significant effects on AR expression in skeletal tissue.

Phase I trial of tirapazamine in combination with cisplatin in a single dose every 3 weeks in patients with solid tumors.

PURPOSE AND METHODS: Tirapazamine (SR4233, WIN 59075) is a benzotriazine-di-N-oxide bioreductive agent that is selectively activated to a reactive DNA-damaging species in hypoxic tumors. Preclinical studies show that synergistic antitumor activity results from a schedule-dependent interaction between tirapazamine and several cytotoxic drug classes, including cisplatin. In a phase I combination study, tirapazamine (130 to 260 mg/m2) was administered as a 1-hour intravenous (IV) infusion beginning 3 hours before cisplatin (75 to 100 mg/m2). Thirteen patients received 41 courses of therapy. These patients had an excellent performance status and were not heavily pretreated. The predominant diagnosis was lung cancer. RESULTS: The major acute side effects were nausea and vomiting, which were controlled with an intensive antiemetic regimen. Other acute effects included diarrhea and muscle cramping, while with repeated dosing, anorexia and fatigue predominated. Full doses of each agent were well tolerated in combination, although in this previously treated population, fatigue increased markedly after three cycles of therapy. Partial responses were observed in two patients (one with non-small-cell lung cancer and one with breast cancer), and a minor response occurred in a patient with mesothelioma. Tirapazamine pharmacokinetics were linear with respect to increasing dose with a mean maximum plasma concentration (Cmax) of 5.97 +/- 2.25 microg/mL and an area under the concentration-time curve (AUC) of 811.4 +/- 311.9 microg/mL.min at 260 mg/m2. These results are consistent with other ongoing single-agent and combination studies and indicate that therapeutically relevant levels of tirapazamine are achievable in patients based on animal models. The mean cisplatin AUC was 285.6 +/- 46.4 microg/mL.min with mean Cmax values of 3.38 +/- 0.43 microg/mL at 75 mg/m2. The clearance of cisplatin was unaffected by coadministration with tirapazamine. CONCLUSION: This trial shows that in previously treated patients, full doses of cisplatin are well tolerated with increasing doses of tirapazamine up to 260 mg/m2. The observation of clinical responses in this trial supports the phase II investigation of this regimen.

Carboplatin and paclitaxel in ovarian carcinoma: a phase I study of the Gynecologic Oncology Group.

PURPOSE: To develop a tolerable, dose-intense regimen of carboplatin and paclitaxel for the treatment of primary epithelial ovarian carcinoma. PATIENTS AND METHODS: Patients underwent initial surgical assessment and tumor debulking. Patients with stage III/IV disease received six cycles of chemotherapy on a planned 21-day cycle. Carboplatin dose was calculated based on projected area under the curve (AUC) for concentration over time (mg. mL-1.min) and escalated to determine the maximum-tolerated dose (MTD). Paclitaxel dose was also escalated as a 3-, 24-, or 96-hour infusion. Granulocyte colony-stimulating factors (G-CSFs) were required at selected dose levels or could be added based on hematologic toxicity. RESULTS: Thirty-nine patients were enrolled and assessable for toxicity and response. Dose-limiting toxicity (DLT) was hematologic, primarily neutropenia. Less than 2% of all cycles with paclitaxel as a 3- or 24-hour infusion were associated with either grade 4 thrombocytopenia or febrile neutropenia. The carboplatin MTD was AUC 7.5 (equivalent to a median dose of 471 mg/m2). The MTD for paclitaxel was 135 mg/m2 over 24 hours and 175 mg/m2 over 3 hours without initial G-CSF. A 96-hour infusion of paclitaxel at a dose of 120 mg/m2 was associated with excessive single-cycle and cumulative myelosuppression, and was not further evaluated. Measured carboplatin AUC agreed well with the calculated AUC. The overall complete (n = 16) and partial (n = 2) response rate among 24 patients with measurable disease was 75%, with a median progression-free survival time of 15 months. CONCLUSION: Carboplatin could be safely combined with paclitaxel using a dose formula based on projected renal clearance. The recommended outpatient regimen is carboplatin AUC 7.5 and paclitaxel 175 mg/m2 over 3 hours without initial G-CSF. This treatment safely achieved a greater dose-intensity of carboplatin than would have been achieved with conventional dosing based on body-surface area.