In-Hospital Methadone Enrollment: a Novel Program to Facilitate Linkage from the Hospital to the Opioid Treatment Program for Vulnerable Patients with Opioid Use Disorder

INTRODUCTION

Methadone ameliorates opioid withdrawal among hospitalized patients with opioid use disorder (OUD). To continue methadone after hospital discharge, patients must enroll in an opioid treatment program (OTP) per federal regulations. Uncontrolled opioid withdrawal is a barrier to linkage from hospital to OTP.

AIM

Describe a federally compliant In-Hospital Methadone Enrollment Team (IN-MEET) that enrolls hospitalized patients with OUD into an OTP with facilitated hospital to OTP linkage.

SETTING

Seven hundred-bed university hospital in Aurora, CO.

PROGRAM DESCRIPTION

A physician dually affiliated with a hospital's addiction consultation service and a community OTP completes an in-hospital, face-to-face medical assessment required by federal law and titrates methadone to comfort. An OTP-affiliated nurse with hospital privileges completes a psychosocial evaluation and provides case management by arranging transportation and providing weekly telephone check-ins.

PROGRAM EVALUATION METRICS

IN-MEET enrollments completed, hospital to OTP linkage, and descriptive characteristics of patients who completed IN-MEET enrollments compared to patients who completed community OTP enrollments.

RESULTS

Between April 2019 and April 2023, our team completed 165 IN-MEET enrollments. Among a subset of 73 IN-MEET patients, 56 (76.7%) presented to the OTP following hospital discharge. Compared to community OTP enrolled patients (n = 1687), a higher percentage of IN-MEET patients were older (39.7 years, standard deviation [SD] 11.2 years vs. 36.1 years, SD 10.6 years) and were unhoused (n = 43, 58.9% vs. n = 199, 11.8%). Compared to community OTP enrolled patients, a higher percentage of IN-MEET patients reported heroin or fentanyl as their primary substance (n = 53, 72.6% vs. n = 677, 40.1%), reported methamphetamine as their secondary substance (n = 27, 37.0% vs. n = 380, 22.5%), and reported they injected their primary substance (n = 46, 63.0% vs. n = 478, 28.3%).

CONCLUSION

IN-MEET facilitates hospital to OTP linkage among a vulnerable population. This model has the potential to improve methadone access for hospitalized patients who may not otherwise seek out treatment.

Promoting appropriate midline catheter and PICC placement through implementation of an EHR-based clinical decision support tool: An interrupted time-series analysis

BACKGROUND

Inappropriate use of peripherally inserted central catheters (PICCs), including multilumen PICCs, may increase the risk of patient complications.

OBJECTIVE

Implement computerized decision support to: (a) increase the use of midline catheters over PICCs when appropriate and (b) decrease PICC lumens when a PICC is necessary.

DESIGNS

Quasi-experimental, interrupted time series.

SETTING

Single tertiary academic medical center.

PATIENTS

Hospitalized adults who received a midline or PICC during clinical care.

INTERVENTION

Decision support on appropriate vascular access device choice via a set of electronic orders embedded within the electronic health record.

MEASUREMENTS

Proportion of midline catheter and single-lumen PICCs placed between January 2, 2017 and November 19, 2017 (preintervention) versus November 20, 2017 to December 1, 2019 (postintervention).

RESULTS

A total of 8758 midline and PICCs were inserted during the study period. A statistically significant increase in the insertion of midline catheters was observed during the intervention (p = .006). In parallel, single-lumen PICC insertion as a proportion of all PICCs also increased after the intervention (p = .035). Results were consistent across multiple disciplines, including internal medicine, surgery, and intensive care. After considering the hospital census, total PICC and midline utilization rates and rates of complications did not change over time. However, an increase in catheter exchanges from less to more invasive devices occurred.

CONCLUSIONS

In this single-center study, the implementation of electronic decision support to inform appropriate catheter use led to a more appropriate midline catheter and single-lumen PICC insertion. Dissemination of this single, effective intervention to examine efficacy in other hospital settings would be welcomed.

External validation of a model to predict future chronic opioid use among hospitalized patients

BACKGROUND

Previous research demonstrates an association between opioid prescribing at hospital discharge and future chronic opioid use. Various opioid guidelines and policies contributed to changes in opioid prescribing practices. How this affected hospitalized patients remains unknown.

OBJECTIVE

Externally validate a prediction model to identify hospitalized patients at the highest risk for future chronic opioid therapy (COT).

DESIGNS

Retrospective analysis of health record data from 2011 to 2022 using logistic regression.

PARTICIPANTS

Hospitalized adults with limited to no opioid use 1-year prior to hospitalization.

SETTINGS

A statewide healthcare system.

MAIN MEASUREMENTS

Used variables associated with progression to COT in a derivation cohort from a different healthcare system to predict expected outcomes in the validation cohort.

KEY RESULTS

The derivation cohort included 17,060 patients, of whom 9653 (56.6%) progressed to COT 1 year after discharge. Compared to the derivation cohort, in the validation cohort, patients who received indigent care (odds ratio [OR] = 0.40, 95% confidence interval [CI] =  0.27-0.59, p < .001) were least likely to progress to COT. Among variables assessed, opioid receipt at discharge was most strongly associated with progression to COT (OR = 3.74, 95% CI = 3.06-4.61, p < .001). The receiver operating characteristic curve for the validation set using coefficients from the derivation cohort performed slightly better than chance (AUC = 0.55).

CONCLUSIONS

Our results highlight the importance of externally validating a prediction model prior to use outside of the derivation population. Periodic updates to models are necessary as policy changes and clinical practice recommendations may affect model performance.

Using Iterative RE-AIM to enhance hospitalist adoption of lung ultrasound in the management of patients with COVID-19: an implementation pilot study

BACKGROUND

Lung ultrasound (LUS) is a clinician-performed evidence-based imaging modality that has multiple advantages in the evaluation of dyspnea caused by multiple disease processes, including COVID-19. Despite these advantages, few hospitalists have been trained to perform LUS. The aim of this study was to increase adoption and implementation of LUS during the 2020 COVID-19 pandemic by using recurrent assessments of RE-AIM outcomes to iteratively revise our implementation strategies.

METHODS

In an academic hospital, we implemented guidelines for the use of LUS in patients with COVID-19 in July 2020. Using a novel "RE-AIM dashboard," we used an iterative process of evaluating the high-priority outcomes of Reach, Adoption, and Implementation at twice monthly intervals to inform revisions of our implementation strategies for LUS delivery (i.e., Iterative RE-AIM process). Using a convergent mixed methods design, we integrated quantitative RE-AIM outcomes with qualitative hospitalist interview data to understand the dynamic determinants of LUS Reach, Adoption, and Implementation.

RESULTS

Over the 1-year study period, 453 LUSs were performed in 298 of 12,567 eligible inpatients with COVID-19 (Reach = 2%). These 453 LUS were ordered by 43 out of 86 eligible hospitalists (LUS order adoption = 50%). However, the LUSs were performed/supervised by only 8 of these 86 hospitalists, 4 of whom were required to complete LUS credentialing as members of the hospitalist procedure service (proceduralist adoption 75% vs 1.2% non-procedural hospitalists adoption). Qualitative and quantitative data obtained to evaluate this Iterative RE-AIM process led to the deployment of six sequential implementation strategies and 3 key findings including (1) there were COVID-19-specific barriers to LUS adoption, (2) hospitalists were more willing to learn to make clinical decisions using LUS images than obtain the images themselves, and (3) mandating the credentialing of a strategically selected sub-group may be a successful strategy for improving Reach.

CONCLUSIONS

Mandating use of a strategically selected subset of clinicians may be an effective strategy for improving Reach of LUS. Additionally, use of Iterative RE-AIM allowed for timely adjustments to implementation strategies, facilitating higher levels of LUS Adoption and Reach. Future studies should explore the replicability of these preliminary findings.

Accumulation of metals and polycyclic aromatic hydrocarbons in agricultural soil after additions of street sediment in southern Ontario

Prior to 2012 street sediment from the Greater Toronto Area was being managed by a local authority and provided to rural landowners under the assumption it was clean fill. The aim of this study was to characterise the chemical and physical composition of that street sediment applied to an agricultural field in southwestern Ontario, Canada and determine if contaminants had migrated to native soil. Soil was sampled from an impact and a background location during the fall of 2016 at four soil depths (0-10, 10-20, 20-30 and 30-40 cm below the surface) to characterise texture, pH, organic content, recoverable metals and total polycyclic aromatic hydrocarbons (PAHs). Textural analysis revealed street sediment was dominated by very coarse and coarse sand which differed from the native silty clay loam and extended to 30 cm below the surface. Some PAHs, including benzo(a)pyrene (1.29 μg g^-1) exceeded the typical regional background concentrations. A distinct pattern of high molecular mass PAHs in the native soil below street sediments suggests that PAHs have migrated to native soil. To our knowledge this is the first study to report PAH concentrations in street sediment in Ontario and to show their potential movement and introduction to native soil. Future studies should focus on transport mechanisms and understanding movement of PAHs in native coarse textured soil.

Abstract P5-16-21: The association of higher tumor HER2 load with treatment response to neoadjuvant therapy in HER2 positive breast cancer patients

Background: Neoadjuvant therapy for HER2 positive invasive breast cancer is used to downstage tumor prior to surgery, objectively measure response, and evaluate novel therapies in clinical trials. Residual Cancer Burden (RCB) established by pathologic evaluation of post-treatment surgical specimens is a marker of tumor response to chemotherapy as well as predictor of recurrence-free survival in HER2 positive breast cancer. The relationship between the HER2 tumor load and the response to chemotherapy in not known.

Specific Aims: To evaluate RCB after neoadjuvant chemotherapy and HER2-targeted treatment for HER2-positive breast cancer, and to determine clinicopathologic factors associated with treatment response as represented by RCB.

Methods: This retrospective chart review included all HER2-positive breast cancer patients, stage I – III, receiving neoadjuvant chemotherapy and HER2-targeted therapy with post-treatment surgical resection at an Allina Health hospital from 2013-2016. Review of clinicopathologic variables included HER2/CEP17 ratio, HER2 absolute copies, ER/PgR status (using the H score calculation), patient age, baseline tumor size, and gross and microscopic pathology review of breast tissue specimens with RCB evaluation completed by breast pathologists. To compare factors related to response, chi-square with Monte-Carlo simulation was used to analyze dichotomous variables, and Mann Whitney U-tests were used for continuous variables.

Findings: The study included 97 patients. Upon surgical resection, complete pathologic response (RCB-0) was found in 47% (46/97 patients), and partial pathologic response (RCB-I) in 15% (15/97 patients). As compared to non-responders (RCB-2 and RCB-3) the complete and partial responders (RCB-0 and RCB-1) were associated with greater HER2/CEP17 ratios (10.2 vs. 6.5; p=0.003), and greater HER2 absolute copies (25 vs. 15.8; p &lt;0.001). Complete responders were associated with lower ER expression (H scores of 89.2 vs. 171.8; p=0.005) than non-responders, with RCB-1 responders associated with ER H-scores between RCB-0 and non-responders (H score=145.9). No significant differences were noted between responders and non-responders on age at diagnosis, pre-treatment tumor size, PgR expression, or the percentage of tumor infiltrating lymphocytes.

Conclusions: The majority of patients with HER2 positive tumors show considerable benefit with neoadjuvant chemotherapy and HER2-targeted treatment (63% in our study) based on RCB assessment. Predictors of response as measured by RCB include high HER2/CEP17 ratios, high absolute copies of HER2 signals by FISH, and lower ER expression.

Citation Format: Lillemoe TJ, Susnik B, Grimm E, Kang S-HL, Swenson KK, Krueger JL, Finkelstein MJ, Tsai ML. The association of higher tumor HER2 load with treatment response to neoadjuvant therapy in HER2 positive breast cancer patients [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-16-21.

Best available technology for European livestock farms: Availability, effectiveness and uptake

Concerns over the negative environmental impact from livestock farming across Europe continue to make their mark resulting in new legislation and large research programs. However, despite a huge amount of published material and many available techniques, doubts over the success of national and European initiatives remain. Uptake of the more cost-effective and environmentally-friendly farming methods (such as dietary control, building design and good manure management) is already widespread but unlikely to be enough in itself to ensure that current environmental targets are fully met. Some of the abatement options available for intensive pig and poultry farming are brought together under the European IPPC/IED directive where they are listed as Best Available Techniques (BAT). This list is far from complete and other methods including many treatment options are currently excluded. However, the efficacies of many of the current BAT-listed options are modest, difficult to regulate and in some cases they may even be counterproductive with respect to other objectives ie pollution swapping. Evaluation of the existing and new BAT technologies is a key to a successful abatement of pollution from the sector and this in turn relies heavily on good measurement strategies. Consideration of the global effect of proposed techniques in the context of the whole farm will be essential for the development of a valid strategy.

Expression of leptin and iNOS in oral melanomas in dogs

BACKGROUND

Oral melanoma (OM) in dogs is an aggressive malignancy, with clinical behavior resembling cutaneous melanomas in humans. Melanoma in humans is promoted by an inflammatory environment that is contributed to by leptin and inducible nitric oxide synthase (iNOS).

OBJECTIVE

To determine if the patterns of leptin and iNOS expression are similar in OM in dogs and cutaneous melanomas in humans.

ANIMALS

Twenty client-owned dogs.

METHODS

Retrospective case study. Immunostaining of the OM tumors from each dog was scored for percentage and intensity of leptin and iNOS expression. Mitotic index was used as an indicator of tumor aggression.

RESULTS

Leptin was detected in ≥75% of the tumor cells in specimens from 11 dogs. One tumor expressed leptin in ≤25% of the cells. The intensity of leptin expression was variable with 6, 9, and 5 cases exhibiting low-, moderate-, and high-intensity staining, respectively. OM with the lowest percentage of iNOS positive cells displayed the highest mitotic indices (P = .006, ANOVA).

CONCLUSIONS AND CLINICAL IMPORTANCE

The expression of leptin is a common finding in melanomas in dogs. These data suggest that the possibility of future clinical applications, such as measuring the concentrations of plasma leptin as a screening tool or leptin as a target for therapy. The relevance of iNOS is not as clear in dogs with OM, for which other directed therapeutics might be more appropriate.

THE ROLE OF THE LYMPHOCYTE IN ANTIBODY FORMATION

Following the injection of typhoid antigen or sheep erythrocytes into the pad of the rabbit's hind foot, lymph from the efferent lymphatic of the popliteal lymph node was collected and analyzed for antibody content. On separating the lymphocytes from the lymph plasma, it was found that the antibody titer of the cell extract was substantially and consistently higher than that of the surrounding fluid. This difference was greatest at the time of greatest rate of increase of antibody titer in the whole lymph, rather than when the antibody titer of the lymph plasma was highest. These results can only be interpreted to mean that the lymphocytes either produce antibodies or take them up from the lymph plasma. Incubation in vitro of lymphocytes containing one species of antibody with lymph plasma containing another showed that antibodies pass from the cells to the supernatant lymph fluid to reach approximate equilibrium; acquisition of antibody from supernatant lymph fluid was not observed. Similar results were obtained when normal lymphocytes were allowed to incubate in vivo in their own lymph fluid to which antibodies had been added. It was again found that antibodies were not absorbed or adsorbed by lymphocytes. These results seem to indicate that lymphocytes are instrumental in the formation of antibodies.

Catalytic activity of caspase-3 is required for its degradation: stabilization of the active complex by synthetic inhibitors

The activation of caspase-3 represents a critical step in the pathways leading to the biochemical and morphological changes that underlie apoptosis. Upon induction of apoptosis, the large (p17) and small (p12) subunits, comprising active caspase-3, are generated via proteolytic processing of a latent proenzyme dimer. Two copies of each individual subunit are generated to form an active heterotetramer. The tetrameric form of caspase-3 cleaves specific protein substrates within the cell, thereby producing the apoptotic phenotype. In contrast to the proenzyme, once activated in HeLa cells, caspase-3 is difficult to detect due to its rapid degradation. Interestingly, however, enzyme stability and therefore detection of active caspase-3 by immunoblot analysis can be restored by treatment of cells with a peptide-based caspase-3 selective inhibitor, suggesting that the active form can be stabilized through protein-inhibitor interaction. The heteromeric active enzyme complex is necessary for its stabilization by inhibitors, as expression of the large subunit alone is not stabilized by the presence of inhibitors. Our results show for the first time, that synthetic caspase inhibitors not only block caspase activity, but may also increase the stability of otherwise rapidly degraded mature caspase complexes. Consistent with these findings, experiments with a catalytically inactive mutant of caspase-3 show that rapid turnover is dependent on the activity of the mature enzyme. Furthermore, turnover of otherwise stable active site mutants of capase-3 is rescued by the presence of the active enzyme suggesting that turnover can be mediated in trans.

In vitro metabolism of the COX-2 inhibitor DFU, including a novel glutathione adduct rearomatization

The metabolic profile of DFU [5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2(5H)-furanone], a potent and selective COX-2 inhibitor, was characterized using in vitro microsomal and hepatocyte incubations. A single product, corresponding to p-hydroxylation, p-OH-DFU [(5,5-dimethyl-3-(3-fluoro-4-hydroxyphenyl)-4-(4-methylsulphonyl)phenyl-2(5H)-furanone)], was produced in rat microsomal incubations of DFU. In contrast, three metabolites were produced in incubations using suspensions of freshly isolated rat hepatocytes. Microsomal production of the p-O-glucuronide metabolite of DFU from synthetic p-OH-DFU was shown to have chromatographic and mass spectrometric properties identical to the earliest eluting hepatocyte metabolite (M1). The molecular weights of the other two hepatocyte metabolites were readily obtained using capillary high-performance liquid chromatography continuous-flow liquid secondary ion mass spectrometry (HPLC/CF-LSIMS); however, the elemental composition of these metabolites was not. Unlike typical metabolic products, which produce readily identified increments in molecular weight, metabolites M2 and M3 produced molecular ions in positive- and negative-ion CF-LSIMS that were consistent with oxidation of DFU (+16 Da), followed by addition of glutathione (+306 Da) and subsequent loss of 20 and 18 Da, respectively. Capillary HPLC/high-resolution CF-LSIMS was used to generate accurate mass data for M2 and M3 that provided evidence that the losses of 20 and 18 Da, respectively, corresponded to a rearomatization through loss of HF or H(2)O. Isolation and NMR characterization provided the definitive structural proof for these metabolites. Overall, the metabolism of DFU in rat hepatocytes is proposed to proceed through an epoxide intermediate, which then either rearranges to the p-OH-DFU and is conjugated with glucuronic acid, or is trapped with glutathione, followed by rearomatization with loss of HF (M2) or H(2)O (M3).

Significance of plasma cytokine levels in melanoma patients with histologically negative sentinel lymph nodes

INTRODUCTION

Although sentinel lymph node (SLN) status is the most powerful predictor of prognosis in patients with clinically localized melanoma, a proportion of melanoma patients with histologically negative SLNs will still recur. It is hypothesized that tumor response may be altered or mediated by specific cytokines. We therefore investigated whether levels of IL-4, IL-6, IL-10, TNF-alpha, or IFN-gamma would predict disease recurrence in melanoma patients with histologically negative SLNs.

METHODS

This prospective cohort study involved 218 patients with clinically localized melanoma who underwent a histologically negative SLN biopsy. Preoperative plasma cytokine levels were determined by enzyme-linked immunosorbent assay on these patients, as well as on 90 healthy controls. Kaplan-Meier life tables were constructed, and Cox proportional hazards analyses were performed to assess predictors of disease-free survival (DFS).

RESULTS

At a median follow-up of 43 months, 33 of 218 patients (15%) had suffered disease recurrence. Melanoma patients had significant elevations of IL-4, IL-6, and IL-10 compared to healthy controls; levels of IFN-gamma were less elevated in melanoma patients compared to controls. Despite this, melanoma patients with detectable IFN-gamma levels were at significantly higher risk for recurrence compared to patients with undetectable levels (5-year DFS 70% vs. 86%, P = .03). On multivariate analysis including standard melanoma prognostic factors, only tumor thickness (P = .004) and the presence of detectable IFN-gamma levels (P = .05) were significant independent prognostic factors for disease-free survival.

CONCLUSIONS

Among melanoma patients with clinically localized disease who have undergone a histologically negative SLN biopsy, presence of a detectable plasma level of IFN-gamma is an independent predictor of disease recurrence. Elevated levels of IFN-gamma may identify a group of early-stage melanoma patients who are more likely to have recurrence of disease and who may benefit from adjuvant therapies, including immunotherapies.

Synthesis, characterization, and activity of metabolites derived from the cyclooxygenase-2 inhibitor rofecoxib (MK-0966, Vioxx)

Metabolites of the COX-2 inhibitor rofecoxib (MK-0966, Vioxx) were prepared by synthetic or biosynthetic methods. Metabolites include products of oxidation, glucuronidation, reduction and hydrolytic ring opening. Based on an in vitro whole blood assay, none of the known human metabolites of rofecoxib inhibits COX-1 nor contributes significantly to the inhibition of COX-2.

Caspase inhibitors improve survival in sepsis: a critical role of the lymphocyte

Sepsis induces lymphocyte apoptosis and prevention of lymphocyte death may improve the chances of surviving this disorder. We compared the efficacy of a selective caspase-3 inhibitor to a polycaspase inhibitor and to caspase-3-/- mice. Both inhibitors prevented lymphocyte apoptosis and improved survival. Caspase-3-/- mice shared a decreased, but not total, block of apoptosis. The polycaspase inhibitor caused a very substantial decrease in bacteremia. Caspase inhibitors did not benefit RAG-1-/- mice, which had a > tenfold increase in bacteremia compared to controls. Adoptive transfer of T cells that overexpressed the anti-apoptotic protein Bcl-2 increased survival. T cells stimulated with anti-CD3 and anti-CD28 produced increased interleukin 2 and interferon gamma by 6 h. Thus, caspase inhibitors enhance immunity by preventing lymphocyte apoptosis and lymphocytes act rapidly, within 24 h, to control infection.

A new structural variation on the methanesulfonylphenyl class of selective cyclooxygenase-2 inhibitors

By inserting an oxygen link between the 3-fluorophenyl and the lactone ring of 5,5-dimethyl-3-(3fluorophenyl)-4-(4-methanesulfonylphenyl)-2 (5H)-furanone 1 (DFU), analogs with enhanced in vitro COX-2 inhibitory potency as well as in vivo potency in models of inflammation were obtained.

SAR in the alkoxy lactone series: the discovery of DFP, a potent and orally active COX-2 inhibitor

Extensive SAR has been established in the alkoxy lactone series and this has lead to the discovery of DFP (5,5-dimethyl-3-(2-propoxy)-4-methanesulfonylphenyl)-2(5H)-furanon e), a potent COX-2 inhibitor exhibiting in vivo efficacy in all models studied.

Rhinovirus replication causes RANTES production in primary bronchial epithelial cells

The mechanisms by which rhinovirus (RV) infections produce lower airway symptoms in asthmatic individuals are not fully established. To determine effects of RV infection on lung epithelial cells, primary human bronchial epithelial (BE) cells were infected with either RV16 or RV49, and viral replication, cell viability, and cell activation were measured. Both viral serotypes replicated in BE cells at 33 degrees C (DeltaTCID50 / ml = 2 to 2.5 log units) and at 37 degrees C (DeltaTCID50 /ml = 1.6 log units), but only high doses of RV49 (10(6) TCID50 /ml) caused cytopathic effects and reduced cell viability. In addition, regulated on activation, normal T cells expressed and secreted (RANTES) secretion was increased in epithelial cells infected with RV16 or RV49 (243 and 398 pg/ml versus 13 pg/ml uninfected control cells), and a similar pattern was seen for RANTES messenger RNA. RV infection also caused increased secretion of interleukin-8 and granulocyte macrophage colony-stimulating factor, but did not alter expression of either intercellular adhesion molecule-1 or human leukocyte-associated antigen-DR. These observations suggest that RVs can replicate in lower airway cells in vivo, and support epidemiologic studies that link RV with lower respiratory illnesses. Further, RV-induced secretion of RANTES and other cytokines could trigger antiviral immune responses in vivo, but these effects could also contribute to the pathogenesis of respiratory symptoms in subjects with asthma.

Exon skipping truncates the PDZ domain of human erythroid p55 in a patient with chronic myeloid leukemia in acute megakaryoblastic blast crisis

Human p55, the major palmitoylated protein associated with the cytoplasmic face of the erythrocyte membrane, is believed to modulate interactions between protein 4.1 and glycophorin C. It is the prototype of a newly described family of signaling molecules that includes hD1g, the human homologue of the Drosophila discs-large tumor suppressor protein. Chronic myeloid leukemia is characterized by transformation to a fulminating acute leukemia, heralded by evolution of the Philadelphia chromosome positive genotype (Ph +) to further abnormalities. RT-PCR of p55 mRNA from a patient with acute megakaryoblastic CML revealed a 69 base pair deletion in the PDZ domain, corresponding to exon 5 of the p55 gene. The deletion of constitutive exon 5 not only marks the first abnormality of the p55 cDNA in human disease but also the first abnormality of a PDZ domain in human disease and may represent another genetic abnormality associated with CML in blast crisis.

Substituted (pyridylmethoxy)naphthalenes as potent and orally active 5-lipoxygenase inhibitors; synthesis, biological profile, and pharmacokinetics of L-739,010

Dioxabicyclooctanyl naphthalenenitriles have been reported as a class of potent and nonredox 5-lipoxygenase (5-LO) inhibitors. These bicyclo derivatives were shown to be metabolically more stable than their tetrahydropyranyl counterparts but were not well orally absorbed. Replacement of the phenyl ring in the naphthalenenitrile 1 by a pyridine ring leads to the potent and orally absorbed inhibitor 3g (L-739,010, 2-cyano-4-(3-furyl)-7-[[6-[3-(3-hydroxy-6,8-dioxabicyclo[3.2.1] octanyl)]-2-pyridyl]methoxy]naphthalene). Compound 3g inhibits 5-HPETE production by human 5-LO and LTB4 biosynthesis by human PMN leukocytes and human whole blood (IC50S of 20, 1.6, and 42 nM, respectively). Derivative 3g is orally active in the rat pleurisy model (inhibition of LTB4, ED50 = 0.3 mg/kg) and in the anesthetized dog model (inhibition of ex vivo whole blood LTB4 and urinary LTE4, ED50 = 0.45 and 0.23 microgram/kg/min, respectively, i.v. infusion). In addition, 3g shows excellent functional activity against ovalbumin-induced dyspnea in rats (60% inhibition at 0.5 mg/kg, 4 h pretreatment) and Ascaris-induced bronchoconstriction in conscious sheep (50% and > 85% inhibition in early and late phases, respectively at 2.5 micrograms/kg/min, i.v. infusion) and, more particularly in the conscious antigen sensitive squirrel monkey model (53% inhibition of the increase in RL and 76% in the decrease of Cdyn, at 0.1 mg/kg, po). In rats and dogs, 3g presents excellent pharmacokinetics (estimated half-lives of 5 and 16 h, respectively) and bioavailabilities (26% and 73% when dosed as its hydrochloride salt at doses of 20 and 10 mg/kg, respectively, in methocel suspension). Based on its overall biological profile, compound 3g has been selected for preclinical animal toxicity studies.

Cytokine-induced cytotoxic function expressed by lymphocytes of the innate immune system: distinguishing characteristics of NK and LAK based on functional and molecular markers

Several molecular events are now identifiable during the activation, recognition, and killing by natural killer (NK) cells that are distinct from those differentiated in response to cytokines during the generation of lymphokine-activated killer (LAK) cells or during lymphocyte proliferation. Because LAK and MHC-unrestricted killing activities also include the prototypic NK targets as part of their broad recognition spectra, accurate identification of the complete function being studied is critical. In many publications, past and present, only NK-sensitive target cells were used (K562, Molt-4, others), and, therefore, the results do not necessarily indicate whether the effectors are NK or have differentiated into LAK cells. Such a consideration becomes critical when the effectors are grown in interleukin-2 (IL-2), and an attempt is made to define receptor recognition, signal transduction pathways, and specificity at the molecular level. In some instances, effector cells are likely to have stopped, therefore merely expressing NK activity, and have also acquired LAK function. The identified receptors may not have been unique to NK cells or NK function. Not until the targets employed are also confirmed to be NK sensitive, and the effectors do not kill NK-resistant targets can the results of molecular studies be proposed to represent aspects unique to NK. Reports of the use of IL-2-expanded NK clones are most likely providing data concerning the biology of LAK and not of classic NK. The classic NK activity surveying our blood apparently performs an important function, including the ability to respond rapidly to certain cytokines and to acquire additional functions and receptors for use in destroying a vast array of target cells. It is critical for scientists to appreciate the functional distinctions and to identify the molecules and pathways unique to each of these curious cytolytic systems.

Molecular analysis of a silent polymorphism in the PDZ domain of p55, the major palmitoylated erythrocyte membrane protein

Two independently published cDNA sequences of p55, the X-linked major palmitoylated erythrocyte membrane protein, revealed a discrepancy between G and T at position 358 (Genbank: M64925). This results in codon 85, in exon 3 in the PDZ (PSD-95, discs-large, Z0-1) domain, being either ACG or ACT. As both ACG and ACT code for threonine, this represents a silent polymorphism. Polymerase chain reaction (PCR), single-stranded conformational polymorphism (SSCP), and direct-sequencing analysis of exon 3 of the p55 gene was performed in 98 subjects of African and European origin. Of the 70 females studied, the frequency of G versus T at position 358 was 0.76:0.24, while of the 28 males, 16 had a G and 12 a T at position 358 (0.57:0.43). In subjects of African origin, the frequency of G versus T at position 358 was 0.78:0.22; in subjects of European origin the ratio was 0.63:0.37.

Rapid purification of recombinant Taq DNA polymerase by freezing and high temperature thawing of bacterial expression cultures

Images

Chemiluminescence intensities and spectra of luminol oxidation by sodium hypochlorite in the presence of hydrogen peroxide

Hydrogen peroxide amplifies the chemiluminescence in the oxidation of luminol by sodium hypochlorite. A linear relationship between concentration of hydrogen peroxide and light intensity was found in the concentration range 5 x 10(-8)-7.5 x 10(-6) mol/l. At 7.5 x 10(-6) mol/l H2O2 the chemiluminescence is amplified 550-fold. The chemiluminescence spectra of these reactions have a wavelength maximum at 431 nm independent of the concentration of hydrogen peroxide. The results indicate that hydrogen peroxide is a necessary component in the chemiluminescent oxidation of the luminol by sodium hypochlorite.

[Computer-assisted drug information]

Experience with a university hospital based drug information service (DIS) is reported. A total of 501 drug related questions were analyzed during two prospective evaluation periods of 13 and 14 months' duration respectively. Information was requested by physicians and pharmacists chiefly on practical aspects of drug treatment in individual patients (77%), such as drug choice, dosage adaptation, side effects and interactions. Inquiries on drug safety in pregnancy and lactation (8.8%), and questions on pharmaceutical properties (14.2%), including pharmacokinetics, were also frequent. Our experience indicates that a problem-oriented, comprehensive DIS necessitates close cooperation between physicians trained in clinical pharmacology and pharmacists within the same team. The use of electronic media greatly facilitates the collection of drug related information, data retrieval and storage. Drug information services can contribute to improved quality and safety of drug therapy.

Mechanism of sucrose retrieval along the phloem path - a kinetic approach

In contrast to hexoses (fructose, glucose, 3-oxymethylglucose) sucrose is preferentially taken up by isolated conducting tissue ofCyclamen persicum Mill. Sucrose absorption follows a biphasic kinetic, with a saturable component (Km=5.2 mM; Vmax = 4.2 μmol · g FW(-1) · h(-1)) in the lower range (<20 mM) and a linear component in the upper range (20-400 mM). The saturable, carrier-mediated uptake operates against the concentration gradient without attaining any equilibrium over 6 h. It is characterized by a pH optimum at 4.5 and sensitivity to the protonophore CCCP (carbonylcyanidem-chlorophenylhydrazone). The activity of the saturable uptake increases with decreasing turgor and it is independent of the presence of hexoses. There is no effect of pH or CCCP on linear sucrose uptake at high external concentrations. Hexose uptake between 0.25 and 20 mM shows a entirely linear kinetic. Leakage after preincubation with 1 mM sucrose exhibits a minimum at pH 5.0 and enters a steady state within 100 min. Furthermore, it was found to be independent of the osmolarity of the external solution. Results are discussed in terms of apoplastic leakage and reabsorption along the phloem path: efflux of sucrose is compensated by a specific, carrier-mediated influx, which is qualitatively similar to apoplastic phloem loading accomplished by proton cotransport. In according with the balanced efflux and influx it should be considered rather as a retrieval than a loading mechanism.

[Case report of tumors in the area of the foramen magnum]

This case study describes a spindle cell glioblastoma of the medulla oblongata (foramen magnum region) in a decreased patient aged 35 years. At the beginning of the illness which lasted about 7 months, the symptoms were quite uncharacteristic, and major neurological failure accompanied by tetraparesis and bulbar symptoms appeared only during the terminal phase, which was of several weeks duration. The specific clinical and diagnostic features of tumours at the magnum foramen, which account for only about 1% of all tumours of the CNS, and the difficulties they entail are described.

[Effect of postoperative parenteral feeding on protein metabolism in heart surgery patients. A comparative study]

To investigate the importance of amino acid infusions in immediate postoperative parenteral nutrition, cardiac patients were randomly allocated into two groups. Applicating identical carbohydrate calories (2000 kcal/day) group 1 received only essential amino acids while in group 2 a combined pattern of essential and non essential amino acids was infused. In addition to routine laboratory data several parameters of protein metabolism including nitrogen balance were evaluated. Although nitrogen balance was positive only in group 2 the differences between the two groups concerning other parameters measured were minimal. The different infusion regimes are discussed revealing the significance of additional parenteral nutrition in these patients.

[Sequential pacing following cardiopulmonary bypass]

Twenty patients with combined mitral valve disease were studied to evaluate whether the mode of cardiac pacing can influence myocardial performance after cardiopulmonary bypass. All patients underwent the same surgical procedure (mitral-valve-replacement) under standardized anaesthetic procedure. After weaning from extracorporeal circulation the following haemodynamic measurements were performed either under ventricular pacing or under sequential ("physiological") pacing: blood-pressure (radial artery), central venous pressure (CVP, jugular vein), cardiac output (as cardiac index, C. I.), pulmonary artery pressure (PAP) using Swan-Ganz-thermodilution catheter (jugular vein) and left atrial pressure (LAP). All patients were investigated as well under ventricular pacing as under sequential pacing (heart rate: 90 X min-1; AV-delay: 200 msec; stimulation with a pacemaker Medtronics 5330). Compared with the situation under ventricular pacing the haemodynamic parameters changed, when sequential pacing was applied: arterial pressure and cardiac output increased, whereas CVP as well as PAP and LAP decreased. The data indicate that there is some influence on cardiac work by the mode of pacing. Physiological pacing compared to ventricular pacing seems to lead to a marked improvement in cardiac performance. Particularly patients with severe dysrhythmia following cardiopulmonary bypass should be treated by physiological (sequential) pacing.

Über den Einfluß der postoperativen parenteralen Ernährung auf den Proteinstoffwechsel kardiochirurgischer Patienten

Es wird über eine vergleichende Ernährungsstudie bei 20 kardiochirurgisch operierten Patienten berichtet. Alternativ wurden bei gleicher Gesamtkalorienzahl parenteral entweder ausschließlich essentielle Aminosäuren (Gruppe 1, n = 10) zugeführt oder ein Gemisch aus essentiellen (45%) und nicht-essentiellen (Gruppe 2, n = 10). Die neben den üblichen Routinelaborparametern ermittelten Meßwerte des Proteinstoffwechsels zeigten bei weitgehend gleichsinnigen Veränderungen beider Gruppen nur ein geringfügiges Unterschreiten der Normbereiche. Die kumulative Stickstoffbilanz war nur in Gruppe 2 positiv. Eine additive parenterale Ernährung erscheint aufgrund der unzureichenden oralen Nahrungsaufnahme kardiochirurgisch operierter Patienten unbedingt angezeigt. Auf die Vor- und Nachteile der verwandten Ernährungsregime wird hingewiesen, wobei der günstige Effekt eines gemischten Aminosäuremusters (in Kombination mit ausreichend hoher Kalorienzufuhr) auf die Stickstoffbilanz unterstrichen wird.

A single cell marker of active NK cytotoxicity: only a fraction of target binding lymphocytes are killer cells

The frequency of cytotoxic NK cells has been directly measured. The cytotoxic assay is performed by preparing conjugates of effector cells bound to target cells and assessing under the microscope target cell lysis by the trypan blue dye exclusion test. With Ficoll-Hypaque purified cells, it was found that 11--13% of lymphocytes formed conjugates with K562 or Molt-4 target cells, but only 3--4% of the total lymphocytes actually killed. Thus, the NK cell's ability to bind targets cannot be equated to the ability to kill. The nature of the noncytotoxic binding lymphocytes is discussed. The kinetics of lysis by NK cells show a random distribution of killing in relationship to time and plateaus at 3--4 hours. The frequency of killing is the same for a wide variety of populations tested at different times. We conclude that some of the target binding cells are antigen specific NK cells that can be converted to cytotoxic natural killer cells.

Frequency determination of K cells by a single cell cytotoxic assay

This report describes a highly reproducible single cell cytotoxic assay which can measure the frequency of K cells in human peripheral blood lymphocytes. This assay is based on the ability of FcR-bearing lymphocytes to bind to antibody sensitized target cells via their FcR. Approximately 30% of lymphocytes which bound antibody sensitized target cells via their FcR. Approximately 30% of lymphocytes which bound antibody sensitized P815 cells (P815-AB) were K cells. Cytolysis of the conjugated P815-AB fulfilled all the criteria for ADCC. Furthermore, an excellent correlation was observed between the frequency of K cells and % cytotoxicity as measured by the ADCC 51Cr-release assay. The mean frequency of human k cells in peripheral blood lymphocytes from 20 volunteers was measured to be 3.2% of the total lymphocyte populations.

[Therapy of ballistic hyperkinesia (case report)]

Discussing the example of two cases of patients suffering from mixed choreic-hemiballistic hemi-hyperkinesia, the authors report on successes they obtained in long-term therapy after surgical stereostactic treatment (high-frequency coagultation) in the thalamus or subthalamus. The discussion deals with indications of the etiology, the supposed pathophysiology and pathomorphology of the disease pictures in question.