Impact on readmission rates and mortality of a chronic obstructive pulmonary disease inpatient management guideline

Aims: Chronic obstructive pulmonary disease (COPD) is a common condition associated with considerable morbidity, mortality and hospital admissions. However, published COPD management guidelines have major limitations and lack practical summaries. We aimed to optimally develop, implement, and evaluate a multidisciplinary COPD inpatient management ‘ACCORD’ guideline, including prompts for comprehensive day one assessments through to a discharge criteria checklist. Method: Two intervention and two control public teaching hospitals in Adelaide, South Australia, took part, with pre-intervention (721 COPD admissions over 7 months) and intervention phases (509 COPD admissions over 7 months). During the intervention stage the ACCORD guideline was placed in the case notes on the day of admission or soon after. Readmissions were categorized as either emergency or elective and compared between the study arms, as were mortality and potential confoundeis (age, gender, number of comorbidities), with Poisson regression analysis. Results: Of case notes of eligible COPD patients, 60% had the ACCORD guideline placed, of which 76% had evidence of use as judged by completion of guideline entry and tick boxes. The ACCORD guideline was associated with an increase in elective admissions and a reduction in emergency admissions in the intervention group in relation to the control group (P < 0.01), with no difference in overall admissions or death rates. Conclusions: The ACCORD guideline was associated with a shift from emergency admissions to more planned elective care, suggesting more proactive care of health problems, but without overall reduction in admissions.

Bak apoptotic pores involve a flexible C-terminal region and juxtaposition of the C-terminal transmembrane domains

Bak and Bax mediate apoptotic cell death by oligomerizing and forming a pore in the mitochondrial outer membrane. Both proteins anchor to the outer membrane via a C-terminal transmembrane domain, although its topology within the apoptotic pore is not known. Cysteine-scanning mutagenesis and hydrophilic labeling confirmed that in healthy mitochondria the Bak α9 segment traverses the outer membrane, with 11 central residues shielded from labeling. After pore formation those residues remained shielded, indicating that α9 does not line a pore. Bak (and Bax) activation allowed linkage of α9 to neighboring α9 segments, identifying an α9:α9 interface in Bak (and Bax) oligomers. Although the linkage pattern along α9 indicated a preferred packing surface, there was no evidence of a dimerization motif. Rather, the interface was invoked in part by Bak conformation change and in part by BH3:groove dimerization. The α9:α9 interaction may constitute a secondary interface in Bak oligomers, as it could link BH3:groove dimers to high-order oligomers. Moreover, as high-order oligomers were generated when α9:α9 linkage in the membrane was combined with α6:α6 linkage on the membrane surface, the α6-α9 region in oligomerized Bak is flexible. These findings provide the first view of Bak carboxy terminus (C terminus) membrane topology within the apoptotic pore.

Evaluating the Development of a SPECT Protocol in a Canadian Epilepsy Unit

Background:

Functional neuroimaging can address some challenges of seizure localization, and sometimes preclude the need for EEG recording using intracranial electrodes. Ictal Single Photon Emission Computed Tomography (SPECT) has developed into an important tool in the presurgical evaluation of patients with medically-intractable localization-related epilepsy. The purpose of the study was to determine whether the development of a programme using trained nurses to perform ictal injections enabled a more efficient delivery of radiopharmaceuticals and therefore a greater sensitivity and specificity of outcome.

Methods:

In our epilepsy unit, nursing staff inject 99mTc-HMPAO at bedside, during or at seizure onset. Brain SPECT is performed later on a gamma camera.

Results:

Since the implementation of the new protocol (February 2005), 57 scans have been performed: 22 ictal and 35 interictal. Latency of ictal injection was found to be 5-40 seconds (mean 19.7 sec, standard deviation (SD) 10.4). Only 20% of reconstituted radiopharmaceutical vials were not used. Contamination rate was nil. Sixty three percent of SPECT studies were concordant with standard presurgical evaluation.

Conclusion:

The latency of injections and the percentage of unused vials indicated an efficient and effective protocol compared to the literature. Our results show that ictal SPECT can be a safe, noninvasive procedure performed on a routine basis in the epilepsy unit when appropriately trained support staff are incorporated into a structured multidisciplinary programme.

Factors affecting surgical results of Wassel type IV thumb duplications

The aim of this study is to review the outcomes of Wassel type IV thumb duplications with a minimum of one year follow-up, and to identify any factors that may compromise the quality of results. Forty one patients (42 thumbs) returned for assessment of thumb alignment, metacarpophalangeal joint and interphalangeal joint stability and motion; carpometacarpal joint motion; pinch and grip strengths; and thumb size. The subjective assessment considered thumb shape and contour, scarring, nail deformity and examiner and patient/parent satisfaction. The mean age at surgery was 16 months and the mean follow-up time was 79 months. Metacarpophalangeal joint and interphalangeal joint mal-alignment was present in 56% and 38% of cases, respectively. Interphalangeal ulnar collateral ligament laxity was significant. Metacarpophalangeal joint and interphalangeal joint motion was significantly decreased. Pinch and grip strength measurements were normal. A novel and comprehensive assessment scale is introduced, which revealed results of one (2.5%) excellent, 23 (59%) good, 14 (36%) fair and one (2.5%) poor. We consider that greater attention should be directed to the avoidance of mal-alignment and instability to improve these results.

Nonclassical light manipulation in a multiple-scattering medium

We investigate the possibility of using a scattering medium as a highly multimode platform for implementing quantum walks. We demonstrate the manipulation of a single photon propagating through a strongly scattering medium using wavefront-shaping technique. Measurement of the scattering matrix allows the wavefront of the photon to be shaped to compensate the distortions induced by multiple scattering events. The photon can thus be directed coherently to a specific output mode. Using this approach, we show how entanglement of a single photon across different modes can be manipulated despite the enormous wavefront disturbance caused by the scattering medium.

Effects of dried plum supplementation on bone metabolism in adult C57BL/6 male mice

Dietary supplementation of dried plum (DP) prevents bone loss and restores bone mass in osteopenic animal models. This study was designed to determine the effects of DP supplementation on bone metabolic activity over time using adult (6-month-old) male C57BL/6 mice (n = 40) receiving control (CON = AIN93 M) or CON+DP 25 % (w/w) diets for 4 or 12 weeks. After 4 weeks of treatment, animals consuming the DP diet had a higher whole-body bone mineral density, vertebral trabecular bone volume (BV/TV), and femoral cortical thickness compared to the CON animals. In the distal metaphysis of the femur, BV/TV was increased in the DP-treated animals, but only after 12 weeks. Bone histomorphometric analyses revealed that DP decreased osteoblast surface (67 %) and osteoclast surface (62 %) at 4 weeks, but these surfaces normalized to the CON animals by 12 weeks. Coincident with these changes, the mineralizing surface (MS/BS) and cancellous bone formation rate (BFR/BS) were reduced at 4 weeks in the DP group compared to the CON, but by 12 weeks of DP supplementation, BFR/BS (~twofold) and MS/BS (~1.7-fold) tended to be increased (p < 0.10). The relative abundance of RNA for key regulators of osteoblast and osteoclast differentiation and indicators of osteoblast activity were reduced in the DP group at 4 weeks with no difference between groups at 12 weeks. These results indicate that supplementing the diet with DP initially suppressed cancellous bone turnover, but a biphasic response occurs over time, resulting in a positive effect on bone mass and structure.

Abstract P2-02-07: Preoperative breast MRI and follow-up recommendations for the contralateral breast influence the rate of contralateral prophylactic mastectomy

Background: Women with breast cancer increasingly choose to undergo contralateral prophylactic mastectomy (CPM) even as the benefit of this procedure for woman at average risk for breast cancer remains uncertain. Many women with newly diagnosed breast cancer undergo pre-operative MRI for a variety of indications. Growing evidence suggests that obtaining a pre-operative MRI increases the likelihood that a patient will choose CPM. This study evaluates the relationship between a pre-operative MRI and the decision to pursue CPM, as well as the rate of contralateral MRI findings for which follow-up is recommended and the choice to undergo CPM. The pathology found in contralateral breasts in this series is also reported.

Methods: Newly diagnosed breast cancer patients were prospectively enrolled in Breast Molecular Epidemiology Resource (B-MER) observational study at the University of Iowa from April 2010 through March 2013. Prophylactic mastectomy is defined as removal of the contralateral breast within 12 months of definitive mastectomy. Univariate logistic regression was used to identify factors predictive of undergoing CPM. Recommended follow-up of the contralateral breast MRI is defined as any imaging or procedure other than immediate ultrasound evaluation.

Results: Among 134 patients (mean age 53) who underwent mastectomy, 53 (40%) underwent CPM. Univariate analysis revealed that patients undergoing CPM were more likely to have had a preoperative bilateral MRI (52%% vs. 28%, p = 0.006) and were more likely to have been given a recommendation for a follow-up test (79% vs, 40%, p = 0.007).

Univariate Analysis of Odds of Electing to Undergo CPMVariableLevelOdds ratioP-valueAge5 year0.62&lt;.001Breast MRIYes vs No2.740.006MRI follow-up recommendationYes or No5.530.007Nodal statusPositive vs Negative0.820.581History of benign breast biopsiesNo vs Yes1.850.209Family history of breast cancerYes vs No1.160.711ER/PR statusNegative vs Positive1.830.134Triple NegativeNo vs Yes1.910.196HER2 statusPositive vs Negative2.470.066BRCA testing doneYes vs No6.04&lt;.001BRCA results*Positive vs Negative3.120.315Tobacco everYes or No1.390.354Alcohol everYes or No1.250.544* Indeterminate and not done levels were excluded from the analysis

Univariate analysis also revealed associations between choice of CPM and younger age (p&lt;0.001) and BRCA testing (p&lt;0.001). In this series, CPM was not associated with nodal status, ER/PR status, history of benign breast biopsies, family history of breast cancer, BRCA result and tobacco or alcohol use, although there was a trend for association with HER2 status. Of the 53 patients who underwent CPM, one had proliferative disease with atypia, 34 had proliferative disease without atypia. A single patient had DCIS found in the contralateral breast which had not been identified on MRI.

Conclusions: The use of preoperative breast MRI and abnormal imaging findings in the contralateral breast, for which follow-up was recommended, led to a higher CPM rate. Contralateral prophylactic mastectomy rarely uncovered occult malignancy.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-02-07.

Large-alphabet time-frequency entangled quantum key distribution by means of time-to-frequency conversion

We introduce a novel time-frequency quantum key distribution (TFQKD) scheme based on photon pairs entangled in these two conjugate degrees of freedom. The scheme uses spectral detection and phase modulation to enable measurements in the temporal basis by means of time-to-frequency conversion. This allows large-alphabet encoding to be implemented with realistic components. A general security analysis for TFQKD with binned measurements reveals a close connection with finite-dimensional QKD protocols and enables analysis of the effects of dark counts on the secure key size.

Sharing milk but not messages: campylobacteriosis associated with consumption of raw milk from a cow-share program in Alaska, 2011

Alaska public and environmental health authorities investigated a cluster of campylobacteriosis cases among people who had consumed raw, unpasteurized milk obtained from a cow-share program in Alaska. Although raw milk is not permitted by law to be offered commercially, consumers can enter into cow-share agreements whereby they contribute funds for the upkeep of cows and in turn receive a share of the milk for their personal use. Laboratory testing of stool specimens collected from ill persons and from cows on the farm revealed an indistinguishable strain of Campylobacter. In this outbreak, numerous confirmed and suspected cases were not among cow shareholders; therefore, these individuals had not been advised of the potential health hazards associated with consumption of raw milk nor were they informed of the outbreak developments.

Ovariectomy and genes encoding core circadian regulatory proteins in murine bone

SUMMARY

This study investigated the influence of ovarian hormone deficiency on core circadian regulatory protein (CCRP) in the context of bone loss. Our data suggest that ovarian hormone deficiency disrupts diurnal rhythmicity and CCRP expression in bone. Further studies should determine if chronobiology provides a novel therapeutic target for osteoporosis intervention.

INTRODUCTION

CCRP synchronize metabolic activities and display an oscillatory expression profile in murine bone. In vitro studies using bone marrow mesenchymal stromal/stem cells have demonstrated that the CCRP is present and can be regulated within osteoblast progenitors. In vivo studies have shown that the CCRP regulates bone mass via leptin/neuroendocrine pathways. The current study used an ovariectomized murine model to test the hypothesis that ovarian hormone deficiency is associated with either an attenuation and/or temporal phase shift of the CCRP oscillatory expression in bone and that these changes are correlated with the onset of osteoporosis.

METHODS

Sham-operated controls and ovariectomized female C57BL/6 mice were euthanized at 4-h intervals 2 weeks post-operatively.

RESULTS

Ovariectomy attenuated the oscillatory expression of CCRP mRNAs in the femur and vertebra relative to the controls and reduced the wheel-running activity profile.

CONCLUSION

Ovarian hormone deficiency modulates the expression profile of the CCRP with potential impact on bone marrow mesenchymal stem cell lineage commitment.

A pilot structured behavioural intervention trial to increase physical activity among women with recent gestational diabetes

Forty-three women were recruited into a 1-year randomised controlled trial to test the feasibility of a structured behavioural intervention to increase physical activity after gestational diabetes. Increases in achievement of physical activity targets were not attained. Recruitment and subject retention were identified as major challenges.

Metal and oxalate contamination in a suburban watershed in the greater Toronto area: the benefits of combining acid leach and selective extraction procedures

Environmentally available concentrations of Fe, Mn, Zn, Cu, Pb, Cr and Ni in soils and sediments from a small suburban catchment, obtained using an acid leach procedure, are compared to the Ontario Ministry of the Environment lowest effect level (LEL) and severe effect levels (SEL) and to Provincial sediment quality guidelines (PSQG's). These data are then compared to the bioavailability, potential bioavailability and non-bioavailability of the same metals, plus oxalate concentration, identified using a selective extraction procedure. This combination of techniques enhanced analytical interpretation with respect to metal mobility and potential metal contamination. Selective extraction highlighted the presence of oxalate as a potential contaminant, especially in poorly drained valley floor deposits (33,633 mg kg(-1) and 26,284 mg kg(-1)) and lakeshore sediments (27,095 mg kg(-1) and 13,729 mg kg(-1)). These levels are considerably in excess of those previously documented in a similar study from Rio de Janeiro, where contamination of urban sediment by sewage is a recognised environmental problem, and could possibly be used both as an indicator of similar contamination and the identification of those areas that warrant further investigation.

Role of Rac1-dependent NADPH oxidase in the growth of pancreatic cancer

K-ras mutations occur in as high as 95% of patients with pancreatic cancer. K-ras activates Rac1-dependent NADPH oxidase, a key source of superoxide. Superoxide plays an important role in pancreatic cancer cell proliferation and scavenging or decreasing the levels of superoxide inhibits pancreatic cancer cell growth both in vitro and in vivo. DNA microarray analysis and RT-PCR has demonstrated that Rac1 is also upregulated in pancreatic cancer. The aim of this study was to determine if inhibiting Rac1 would alter pancreatic tumor cell behavior. Human pancreatic cancer cells with mutant K-ras (MIA PaCa-2), wild-type K-ras (BxPC-3), and the immortal H6c7 cell line (pancreatic ductal epithelium) expressing K-ras oncogene (H6c7eR-KrasT) that is tumorigenic, were infected with a dominant/negative Rac1 construct (AdN17Rac1). In cells with mutant K-ras, AdN17Rac1 decreased rac activity, decreased superoxide levels, and inhibited in vitro growth. However in the BxPC-3 cell line, AdN17Rac1 did not change rac activity, superoxide levels, or in vitro cell growth. Additionally, AdN17Rac1 decreased superoxide levels and inhibited in vitro growth in the KrasT tumorigenic cell line, but had no effect in the immortalized H6c7 cell line. In human pancreatic tumor xenografts, intratumoral injections of AdN17Rac1 inhibited tumor growth. These results suggest that activation of Rac1-dependent superoxide generation leads to pancreatic cancer cell proliferation. In pancreatic cancer inhibition of Rac1 may be a potential therapeutic target.

Central melanocortin stimulation increases phosphorylated perilipin A and hormone-sensitive lipase in adipose tissues

Norepinephrine (NE) released from the sympathetic nerves innervating white adipose tissue (WAT) is the principal initiator of lipolysis in mammals. Central WAT sympathetic outflow neurons express melanocortin 4-receptor (MC4-R) mRNA. Single central injection of melanotan II (MTII; MC3/4-R agonist) nonuniformly increases WAT NE turnover (NETO), increases interscapular brown adipose tissue (IBAT) NETO, and increases the circulating lipolytic products glycerol and free fatty acid. The WAT pads that contributed to this lipolysis were inferred from the increases in NETO. Because phosphorylation of perilipin A (p-perilipin A) and hormone-sensitive lipase are necessary for NE-triggered lipolysis, we tested whether MTII would increase these intracellular markers of lipolysis. Male Siberian hamsters received a single 3rd ventricular injection of MTII or saline. Trunk blood was collected at 0.5, 1.0, and 2.0 h postinjection from excised inguinal, retroperitoneal, and epididymal WAT (IWAT, RWAT, and EWAT, respectively) and IBAT pads. MTII increased circulating glycerol concentrations at 0.5 and 1.0 h, whereas free fatty acid concentrations were increased at 1.0 and 2.0 h. Western blot analysis showed that MTII specifically increased p-perilipin A and hormone-sensitive lipase only in fat pads that previously had MTII-induced increases in NETO. Phosphorylation increased in IWAT at all time points and IBAT at 0.5 h, but not RWAT or EWAT at any time point. These results show for the first time in rodents that p-perilipin A can serve as an in vivo, fat pad-specific indictor of lipolysis and extend our previous findings showing that central melanocortin stimulation increases WAT lipolysis.

A translating stage system for µ-PIV measurements surrounding the tip of a migrating semi-infinite bubble

We have designed, fabricated and evaluated a novel translating stage system (TSS) that augments a conventional micro particle image velocimetry (µ-PIV) system. The TSS has been used to enhance the ability to measure flow fields surrounding the tip of a migrating semi-infinite bubble in a glass capillary tube under both steady and pulsatile reopening conditions. With conventional µ-PIV systems, observations near the bubble tip are challenging because the forward progress of the bubble rapidly sweeps the air-liquid interface across the microscopic field of view. The translating stage mechanically cancels the mean bubble tip velocity, keeping the interface within the microscope field of view and providing a tenfold increase in data collection efficiency compared to fixed-stage techniques. This dramatic improvement allows nearly continuous observation of the flow field over long propagation distances. A large (136-frame) ensemble-averaged velocity field recorded with the TSS near the tip of a steadily migrating bubble is shown to compare well with fixed-stage results under identical flow conditions. Use of the TSS allows the ensemble-averaged measurement of pulsatile bubble propagation flow fields, which would be practically impossible using conventional fixed-stage techniques. We demonstrate our ability to analyze these time-dependent two-phase flows using the ensemble-averaged flow field at four points in the oscillatory cycle.

Building capacity in local government for integrated planning to increase physical activity: evaluation of the VicHealth MetroACTIVE program

Integrated planning is a holistic approach to addressing the needs of local communities built on partnerships between those responsible for development, environmental quality and service provision. This study investigated the extent and key influences on the use of integrated planning to promote physical activity among six metropolitan councils in Melbourne Australia, which took part in the MetroACTIVE Project funded by the Victorian Health Promotion Foundation from 2005 to 2007. The evaluation entailed interviews conducted at the mid-term (N = 67) and completion (N = 50) of the project, and the review of relevant documents. Respondents included elected councillors, chief executive officers, officers from different council divisions and the project staff employed in each council. Three councils showed evidence of integrated planning for physical activity, whereas the remainder focused on the delivery of community participation programs. Leadership from senior management and an organizational culture that supported collaboration across council departments were prerequisites for integrated planning. Employment of a dedicated project officer with skills for engaging management and building partnerships within the organization was important. Barriers to integrated planning were a complex organization structure, high demands on the council due to a growing residential population and a poor climate among staff. Overall, integrated planning was found to be a viable approach for developing a coordinated approach to this issue involving the range of council services and functions. Ongoing strategies are needed to facilitate senior management commitment and organizational capacity for integrated planning, with leadership provided by departments responsible for infrastructure or corporate planning.

Atomic positional versus electronic order in semiconducting ZnSe nanoparticles

Size-controlled ZnSe nanoparticles with high extents of atomic positional order are shown to exhibit large size-dependent variations in their local electronic environments. Solid-state ;{77}Se and ;{67}Zn NMR spectra reveal increasingly broad distributions of ;{77}Se and ;{67}Zn environments with decreasing nanoparticle sizes, in contrast with high degrees of atomic positional order established by transmission electron microscopy and x-ray diffraction. First-principles calculations of NMR parameters distinguish between atomic positional and electronic disorder that propagate from the nanoparticle surfaces and yield insights on the order and disorder present.

Providing reviews of evidence to COPD patients: controlled prospective 12-month trial

The aim of this study was to evaluate a novel patient-held manual designed to reduce the evidence–practice gap in chronic obstructive pulmonary disease (COPD). The intervention manual contained summaries of research evidence. It was developed using current best practice for patient information materials and designed to cause discussion of evidence between patient and doctor. A controlled before-and-after study was employed in two similar but geographically separate regions of metropolitan Adelaide, South Australia. Participants had moderate to severe COPD, with 249 included at baseline and 201 completing the study. Evidence-based COPD management was measured using an indicator with three components: rates of influenza vaccination, bone density testing, and pulmonary rehabilitation. A survey of behavioral steps leading to practice change was conducted with the trial. Analysis, by median split of socioeconomic disadvantage, showed significant difference between study arms for only one component of the indicator of evidence-based practice, enrolment in pulmonary rehabilitation and only for the most socioeconomically disadvantaged stratum. For both socioeconomic strata, more intervention participants than control participants reported remembering being given the information material, reading part or all, and finding it very or quite helpful. Other significant differences were restricted to the stratum of greatest socioeconomic disadvantage: reading all of the material, learning from it, referring back, and talking to a doctor about a topic from the material. Above 90% of all participants who received the manual reported reading from it, 42% reported discussing topics with a doctor, but only 10% reported treatment change attributable to the manual. We have found that people with COPD will read an evidence manual developed using current best practice. However, the study demonstrated improvement for only one of the three components of an indicator of evidence-based disease management for only the most socioeconomically disadvantaged stratum of participants. Future interventions should be designed to better translate reading uptake into evidence-based disease management.

BRCA2 alteration is important in clear cell carcinoma of the ovary

BRCA2 has been shown to play a significant role in hereditary ovarian carcinoma. Several cases of clear cell carcinoma (CCC) of the ovary containing BRCA2 mutations have been identified. We hypothesize that sequence variants of the BRCA2 gene are common in CCC of the ovary. Multiple methods were utilized to detect BRCA2 genetic alterations in a cohort of 13 ovarian CCC. These included an LOH analysis for copy number, real-time and methylation-specific polymerase chain reaction (PCR) to probe for BRCA2 promoter methylation, in addition to protein truncation testing (PTT) gel screening for nonsense BRCA2 mutations, and finally direct gene sequencing to either confirm the nonsense mutations or to detect candidate missense mutations in the remaining tumor samples. Whenever a sequence variation was detected in a tumor sample, the corresponding region was sequenced from a blood sample to determine germline status. Seven BRCA2 sequence variations were identified in 6 of the 13 CCC (46%); three tumors contained an alteration in BRCA2 copy number. Only one subject carried a germline sequence variation that might alter BRCA2 function despite the fact that a family history of breast, ovarian or colon cancer was common in this population. The 5-year disease-specific survival probability for patients with a BRCA2 alteration is 87.5%, compared to only 40% for those patients without a BRCA2 alteration (p = 0.39). Alterations in BRCA2 gene sequence, copy number, or expression are extremely common in CCC and may contribute to a paradoxical better clinical outcome.

Absolute efficiency estimation of photon-number-resolving detectors using twin beams

A nonclassical light source is used to demonstrate experimentally the absolute efficiency calibration of a photon-number-resolving detector. The photon-pair detector calibration method developed by Klyshko for single-photon detectors is generalized to take advantage of the higher dynamic range and additional information provided by photon-number-resolving detectors. This enables the use of brighter twin-beam sources including amplified pulse pumped sources, which increases the relevant signal and provides measurement redundancy, making the calibration more robust.

Optimal quantum phase estimation

By using a systematic optimization approach, we determine quantum states of light with definite photon number leading to the best possible precision in optical two-mode interferometry. Our treatment takes into account the experimentally relevant situation of photon losses. Our results thus reveal the benchmark for precision in optical interferometry. Although this boundary is generally worse than the Heisenberg limit, we show that the obtained precision beats the standard quantum limit, thus leading to a significant improvement compared to classical interferometers. We furthermore discuss alternative states and strategies to the optimized states which are easier to generate at the cost of only slightly lower precision.

Engineering a stable and selective peptide blocker of the Kv1.3 channel in T lymphocytes

Kv1.3 potassium channels maintain the membrane potential of effector memory (T(EM)) T cells that are important mediators of multiple sclerosis, type 1 diabetes mellitus, and rheumatoid arthritis. The polypeptide ShK-170 (ShK-L5), containing an N-terminal phosphotyrosine extension of the Stichodactyla helianthus ShK toxin, is a potent and selective blocker of these channels. However, a stability study of ShK-170 showed minor pH-related hydrolysis and oxidation byproducts that were exacerbated by increasing temperatures. We therefore engineered a series of analogs to minimize the formation of these byproducts. The analog with the greatest stability, ShK-192, contains a nonhydrolyzable phosphotyrosine surrogate, a methionine isostere, and a C-terminal amide. ShK-192 shows the same overall fold as ShK, and there is no evidence of any interaction between the N-terminal adduct and the rest of the peptide. The docking configuration of ShK-192 in Kv1.3 shows the N-terminal para-phosphonophenylalanine group lying at the junction of two channel monomers to form a salt bridge with Lys(411) of the channel. ShK-192 blocks Kv1.3 with an IC(50) of 140 pM and exhibits greater than 100-fold selectivity over closely related channels. After a single subcutaneous injection of 100 microg/kg, approximately 100 to 200 pM concentrations of active peptide is detectable in the blood of Lewis rats 24, 48, and 72 h after the injection. ShK-192 effectively inhibits the proliferation of T(EM) cells and suppresses delayed type hypersensitivity when administered at 10 or 100 microg/kg by subcutaneous injection once daily. ShK-192 has potential as a therapeutic for autoimmune diseases mediated by T(EM) cells.

Multimodal techniques for smoking cessation: a review of their efficacy and utilisation and clinical practice guidelines

AIMS

Nicotine addiction is a complex, chronic condition with physiological and psychological/behavioural aspects that make smoking cessation extremely difficult. This paper reviews current recommendations for smoking cessation and the efficacy of pharmacotherapy and behavioural modification techniques, used either alone or in combination, for smoking cessation.

RESULTS

Abstinence rates for pharmacotherapies range from approximately 16% to approximately 30% at 1-year follow-up, with efficacy odds ratios (ORs) compared with placebo of approximately 1.7 for nicotine replacement therapy (NRT), approximately 1.9 for bupropion sustained release and approximately 3.0 for varenicline. Behaviour modification therapies have achieved quit rates of between 8% and 43% for up to 1 year, with ORs in comparison to no treatment of between approximately 1.2 and approximately 2.2. No direct comparisons have been made between pharmacotherapy alone and psychological behaviour strategies alone. However, combining physiological approaches with counselling significantly increases the odds of quitting compared with either technique alone.

CONCLUSIONS

Applying multimodal techniques for the treatment of nicotine addiction is the recommended approach and has demonstrated the potential to improve rates of permanent abstinence in smokers attempting cessation. While the numbers of patients receiving help and advice regarding smoking cessation is increasing, the multimodal approach appears to be currently underutilised by clinicians and therefore smoking cessation strategies are not being optimised.