Effect of buprenorphine dose on treatment outcome

The goal of this meta-analysis is to provide evidence based information about proper dosing for buprenorphine maintenance treatment to improve treatment outcome. To be selected for the review and inclusion in the meta-analysis, articles had to be randomized, controlled, or double-blind clinical trials, with buprenorphine as the study drug; the length of buprenorphine maintenance treatment had to be 3 weeks or longer; doses of buprenorphine had to be clearly stated; outcome measures had to include retention rates in buprenorphine treatment; outcome measures had to include illicit opioid use based on analytical determination of drugs of abuse in urine samples as outcome variables; and outcome measures had to include illicit cocaine use based on analytical determination of drugs of abuse in urine samples as outcome variables. Twenty-nine articles were excluded because they did not meet the inclusion criteria. The authors present the results of 21 articles that met inclusion criteria. The higher buprenorphine dose (16-32 mg per day) predicted better retention in treatment compared with the lower dose (less than 16 mg per day) (P = .009, R(2) adjusted = 0.40), and the positive urine drug screens for opiates predicted dropping out of treatment (P = .019, R(2) Adjusted = 0.40). Retention in treatment predicted less illicit opioid use (P = .033, R(2) Adjusted = 0.36), and the positive urine drug screens for cocaine predicted more illicit opioid use (P = .021, R(2) Adjusted = 0.36). Strong evidence exists based on 21 randomized clinical trials that the higher buprenorphine dose may improve retention in buprenorphine maintenance treatment.     

Induction of p21 (CIP1/WAF1/SID1) by estradiol in a breast epithelial cell line transfected with the recombinant estrogen receptor gene:

Estrogens stimulate the growth of a majority of estrogen receptor (ER)-positive breast cancer cells. In contrast, estradiol exerted a 75% inhibition of DNA synthesis in the MCF-10AE^wt5 cell line, obtained by the transfection of the ER gene into a normal breast epithelial cell line, MCF-10A. The estradiol-mediated growth inhibitory effect was reversed by ICI 164384, a pure anti-estrogen. Analysis of cell cycle by flow cytometry showed a significant increase of G1 cells by estradiol treatment compared to controls. To understand the mechanism of action of estradiol on MCF-10AE^wt5 cells, we examined the level of a cyclin dependent kinase inhibitor (CKI), p21, by Western blot analysis. Our results showed a 5- to 10-fold increase in the level of p21 in estradiol-treated MCF-10AE^wt5 cells compared to controls. ICI 164384 reversed estradiol-mediated induction of p21. Northern blot analysis of p21 mRNA indicated that estradiol stimulated its message in MCF-10AE^wt5 cells. Analysis of a panel of 6 breast cancer cell lines showed the absence of p21 protein, whereas it was present at a very low level in MCF-10A cells. Comparison of p21 in MCF-10A and MCF-10AE^wt5 cells showed an abundance of p21 in the ER-transfected cells. However, this p21 appears to be inactive in the absence of estradiol. These results suggest a p21-mediated pathway as a possible mechanism for the growth inhibitory effects of estradiol on at least a subset of ER-transfected cell lines.     

Amelioration of emphysema in mice through lentiviral transduction of long-lived pulmonary alveolar macrophages

Directed gene transfer into specific cell lineages in vivo is an attractive approach for both modulating gene expression and correcting inherited mutations such as emphysema caused by human α1 antitrypsin (hAAT) deficiency. However, somatic tissues are mainly comprised of heterogeneous, differentiated cell lineages that can be short lived and difficult to specifically transfect. Here, we describe an intratracheally instilled lentiviral system able to deliver genes selectively to as many as 70% of alveolar macrophages (AMs) in the mouse lung. Following a single in vivo lentiviral transduction, genetically tagged AMs persisted in lung alveoli and expressed transferred genes for the lifetime of the adult mouse. A prolonged macrophage lifespan, rather than precursor cell proliferation, accounted for the surprisingly sustained presence of transduced AMs. We utilized this long-lived population to achieve localized secretion of therapeutic levels of hAAT protein in lung epithelial lining fluid. In an established mouse model of emphysema, lentivirally delivered hAAT ameliorated the progression of emphysema, as evidenced by attenuation of increased lung compliance and alveolar size. After 24 weeks of sustained gene expression, no humoral or cellular immune responses to hAAT protein were detected. Our results challenge the dogma that AMs are short lived and suggest that these differentiated cells may be a possible target cell population for in vivo gene therapy applications, including the sustained correction of hAAT deficiency.     

Evidence for the association of synaptotagmin with glutathione S-transferases: implications for a novel function in human breast cancer

OBJECTIVE: To analyze the pattern of changes in GSTs in cancerous and adjacent non-cancerous tissues obtained from breast cancer patients undergoing surgery. DESIGN AND METHODS: Cytosolic GST purification, assay of GST, protein expression levels, and GST-synaptotagmin association were analyzed using standard biochemical techniques like GSH-affinity purification, spectrophotometry, SDS-PAGE, Western blots, and matrix-assisted laser desorption and ionization-time of flight (MALDI-TOF). RESULTS: GST activity in cancerous tissues (0.26 U/mg protein) was significantly higher (P < 0.05) as compared to those from adjacent non-cancerous tissues (0.14 U/mg protein) of breast cancer patients. Further analysis of GST subunits on SDS-PAGE and Western blots using class-specific GST antibodies revealed significant elevation in GST-pi levels in cancer tissues with no appreciable changes in GST-alpha and GST-mu. Along with the elevation of GST-pi levels, high molecular weight proteins (approximately 70 kDa) cross reacting with GST antibodies were detected only in surgically resected tumor biopsies but not in the non-cancerous tissues adjacent to the tumor. Based on MALDI-TOF analysis, the high molecular weight band was identified as synaptotagmin V bound to GST-M1 with 47% sequence coverage after processing on an MS-FIT search engine. CONCLUSIONS: Our results suggest a novel putative functional role for the GST-synaptotagmin complex in human breast cancers. As this association of GST M1-synaptotagmin was not seen in adjacent non-cancerous tissues, this can be used as a marker for breast cancers.     

Insulin-degrading activity in wound fluid

Patients with diabetes are at great risk of developing lower extremity ulcers. The management of diabetic foot ulcers typically includes early recognition and appropriate clinical care. Recent advances in wound treatment include topical growth factor therapy, which has been successful in diabetic wounds. Growth factors are decreased in wound fluid; this may be due to decreased supply, increased binding, or increased degradation of the naturally occurring growth factors. This study investigates the activity of the insulin-degrading enzyme in wound fluid. Wound fluid was obtained from patients with (n = 17) and without (n = 4) diabetes. Insulin degradation was assayed by incubating [(125)I]insulin with wound fluid and precipitation in trichloroacetic acid. Fluid from nondiabetics degraded 2.22 +/- 0.73%, whereas diabetic fluid degraded significantly more (6.13 +/- 1.48%; P < 0.05). In patients with diabetes, the degradation of insulin by wound fluid correlated with glucose control (hemoglobin A(1c); r(2) = 0.5353; P < 0.001), and patients with worse outcomes (i.e. amputation) had higher wound fluid insulin degradation. The biochemical characteristics of insulin degradation in the wound fluid were consistent with the characteristics of insulin-degrading enzyme. These data suggest that glucose control is a critical factor in wound healing, but a reduction in the insulin-degrading activity in the wound fluid is also a potential therapeutic target.     

Devices in heart failure: potential methods for device-based monitoring of congestive heart failure

Congestive heart failure has long been one of the most serious medical conditions in the United States; in fact, in the United States alone, heart failure accounts for 6.5 million days of hospitalization each year. One important goal of heart-failure therapy is to inhibit the progression of congestive heart failure through pharmacologic and device-based therapies. Therefore, there have been efforts to develop device-based therapies aimed at improving cardiac reserve and optimizing pump function to meet metabolic requirements. The course of congestive heart failure is often worsened by other conditions, including new-onset arrhythmias, ischemia and infarction, valvulopathy, decompensation, end-organ damage, and therapeutic refractoriness, that have an impact on outcomes. The onset of such conditions is sometimes heralded by subtle pathophysiologic changes, and the timely identification of these changes may promote the use of preventive measures. Consequently, device-based methods could in the future have an important role in the timely identification of the subtle pathophysiologic changes associated with congestive heart failure.