It's not what you think: shaping beliefs about a robot to influence a teleoperator's expectations and behavior

In this paper we present a novel design approach for shaping a teleoperator's expectations and behaviors when teleoperating a robot. Just as how people may drive a car differently based on their expectations of it (e.g., the brakes may be poor), we assert that teleoperators may likewise operate a robot differently based on expectations of robot capability and robustness. We present 3 novel interaction designs that proactively shape teleoperator perceptions, and the results from formal studies that demonstrate that these techniques do indeed shape operator perceptions, and in some cases, measures of driving behavior such as changes in collisions. Our methods shape operator perceptions of a robot's speed, weight, or overall safety, designed to encourage them to drive more safely. This approach shows promise as an avenue for improving teleoperator effectiveness without requiring changes to a robot, novel sensors, algorithms, or other functionality.

Remembering the victims of COVID-19: From personal to civic to reparative memory

In March 2020, the Covid-19 pandemic had exploded in New York City, across the country, and around the world. At its height, thousands of people were dying every day in quarantined intensive care units and Covid wards, their families forbidden from attending their loved ones' last living moments, even to say good-bye. The victims were dying in isolation, consigned to make-shift morgues, and buried or cremated-without ceremony, without grieving loved ones present. To commemorate the victims of Covid communally in real time would also be to turn the mourners themselves into new Covid victims. Commemorative and collective grieving processes would have to be deferred until it was safe to gather together again. But memory deferred is also memory transformed with new and devastating meaning. In this short reflection on how the meanings engendered by memory of those lost to Covid-19 morph over time, I explore the differences between the memory of personal loss, civic memory, and reparative memory.

Say what you want, I’m not listening!

We present a conversational social robot behaviour design that draws from psychotherapy research to support individual self-reflection and wellbeing, without requiring the robot to parse or otherwise understand what the user is saying. This simplicity focused approached enabled us to intersect the well-being aims with privacy and simplicity, while achieving high robustness. We implemented a fully autonomous and standalone (not network enabled) prototype and conducted a proof-of-concept study as an initial step to test the feasibility of our behaviour design: whether people would successfully engage with our simple behaviour and could interact meaningfully with it. We deployed our robot unsupervised for 48 h into the homes of 14 participants. All participants engaged with self-reflection with the robot without reporting any interaction challenges or technical issues. This supports the feasibility of our specific behaviour design, as well as the general viability of our non-parsing simplicity approach to conversation, which we believe to be an exciting avenue for further exploration. Our results thus pave the way for further exploring how conversational behaviour designs like ours may support people living with loneliness.

Loss of G0/G1 switch gene 2 (G0S2) promotes disease progression and drug resistance in chronic myeloid leukaemia (CML) by disrupting glycerophospholipid metabolism

Tyrosine kinase inhibitors (TKIs) targeting BCR::ABL1 have turned chronic myeloid leukaemia (CML) from a fatal disease into a manageable condition for most patients. Despite improved survival, targeting drug-resistant leukaemia stem cells (LSCs) remains a challenge for curative CML therapy. Aberrant lipid metabolism can have a large impact on membrane dynamics, cell survival and therapeutic responses in cancer. While ceramide and sphingolipid levels were previously correlated with TKI response in CML, the role of lipid metabolism in TKI resistance is not well understood. We have identified downregulation of a critical regulator of lipid metabolism, G0/G1 switch gene 2 (G0S2), in multiple scenarios of TKI resistance, including (1) BCR::ABL1 kinase-independent TKI resistance, (2) progression of CML from the chronic to the blast phase of the disease, and (3) in CML versus normal myeloid progenitors. Accordingly, CML patients with low G0S2 expression levels had a worse overall survival. G0S2 downregulation in CML was not a result of promoter hypermethylation or BCR::ABL1 kinase activity, but was rather due to transcriptional repression by MYC. Using CML cell lines, patient samples and G0s2 knockout (G0s2-/- ) mice, we demonstrate a tumour suppressor role for G0S2 in CML and TKI resistance. Our data suggest that reduced G0S2 protein expression in CML disrupts glycerophospholipid metabolism, correlating with a block of differentiation that renders CML cells resistant to therapy. Altogether, our data unravel a new role for G0S2 in regulating myeloid differentiation and TKI response in CML, and suggest that restoring G0S2 may have clinical utility.

19S Proteasome Subunits as Oncogenes and Prognostic Biomarkers in FLT3-Mutated Acute Myeloid Leukemia (AML)

26S proteasome non-ATPase subunits 1 (PSMD1) and 3 (PSMD3) were recently identified as prognostic biomarkers and potential therapeutic targets in chronic myeloid leukemia (CML) and multiple solid tumors. In the present study, we analyzed the expression of 19S proteasome subunits in acute myeloid leukemia (AML) patients with mutations in the FMS-like tyrosine kinase 3 (FLT3) gene and assessed their impact on overall survival (OS). High levels of PSMD3 but not PSMD1 expression correlated with a worse OS in FLT3-mutated AML. Consistent with an oncogenic role for PSMD3 in AML, shRNA-mediated PSMD3 knockdown impaired colony formation of FLT3+ AML cell lines, which correlated with increased OS in xenograft models. While PSMD3 regulated nuclear factor-kappa B (NF-κB) transcriptional activity in CML, we did not observe similar effects in FLT3+ AML cells. Rather, proteomics analyses suggested a role for PSMD3 in neutrophil degranulation and energy metabolism. Finally, we identified additional PSMD subunits that are upregulated in AML patients with mutated versus wild-type FLT3, which correlated with worse outcomes. These findings suggest that different components of the 19S regulatory complex of the 26S proteasome can have indications for OS and may serve as prognostic biomarkers in AML and other types of cancers.

Abstract P150: PSMD1 and PSMD3 as putative targets for cancer therapy

Ever since the ubiquitin proteasome system was characterized, efforts have been made to manipulate its function to abrogate the progression of cancer. As a result, the anticancer drugs bortezomib, carfilzomib, and ixazomib targeting the 26S proteasome were developed to treat multiple myeloma, mantle cell lymphoma, diffuse large B-cell lymphoma, colorectal cancer, and thyroid carcinoma. Despite the success demonstrated by these treatments, adverse side effects and drug resistance are prominent, raising the need for alternative therapeutic options. The 26S proteasome is composed of two 19S regulatory subunits and a 20S catalytic core, leaving ample opportunity for new targets. We recently demonstrated that knockdown of the 19S regulatory subunits, proteasome 26S subunit, non-ATPases 1 (PSMD1) and 3 (PSMD3), resulted in increased apoptosis of tyrosine kinase inhibitor (TKI)-resistant chronic myeloid leukemia (CML) cells, but had no effect on normal cord blood controls, suggesting they may be good targets for therapy. Therefore, we hypothesized that PSMD1 and PSMD3 are potential targets for anticancer therapeutics and that their relevance stretches beyond CML to other types of cancers. In the present study, we analyzed PSMD1 and PSMD3 expression in other types of cancers versus normal controls using data from The Cancer Genome Atlas (TCGA) and the Clinical Proteomic Tumor Analysis Consortium (CPTAC), comparing expression with overall survival (OS). Data were analyzed using UALCAN (http://ualcan.path.uab.edu) and GEPIA2 (http://gepia2.cancer-pku.cn/). At the mRNA level, PSMD1 was found to be overexpressed in 14/24 (58%) TCGA cancers compared with normal controls. This was confirmed at the protein level for breast (p=4.2e-4), colon (p=7.1e-20), clear cell renal carcinoma (p=1.8e-4), and endometrial cancer (p=2.0e-22). PSMD3 was found upregulated at the mRNA level in 18/24 (75%) TCGA cancers, which was confirmed at the protein level in breast (p=8.3e-4), colon (p=1.0e-27), ovarian (p=4.2e-6), clear cell renal carcinoma (p=4.0e-19), and endometrial cancer (p=1.5e-19). Upon correlation of PSMD1 expression with OS, we saw that when overexpressed, individuals did significantly worse with adrenocortical carcinoma, lower grade glioma, lung adenocarcinoma, mesothelioma, and uveal melanoma. In contrast, diffuse large B cell lymphoma (DLBCL) and stomach adenocarcinoma patients with lower PSMD1 expression had a worse OS. Similarly, patients with high levels of PSMD3 mRNA expression had a significantly worse OS in kidney chromophobe, skin cutaneous melanoma, uveal melanoma, and mesothelioma. Our analysis revealed that differential expression of PSMD1 and PSMD3 is correlated with survival in several different cancer types. Future directions will identify PSMD1 and PSMD3 post-translational modifications that may be novel targets for anticancer therapeutics. In conclusion, we highlight PSMD1 and PSMD3 as potential therapeutic targets for the development of novel proteasome inhibitors to treat cancer patients with less toxicity.

Citation Format: Andres J. Rubio, Alfonso E. Bencomo-Alvarez, James E. Young, Vanessa V. Velazquez, Anna M. Eiring. PSMD1 and PSMD3 as putative targets for cancer therapy [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P150.

26S Proteasome Non-ATPase Regulatory Subunits 1 (PSMD1) and 3 (PSMD3) as Putative Targets for Cancer Prognosis and Therapy

Ever since the ubiquitin proteasome system was characterized, efforts have been made to manipulate its function to abrogate the progression of cancer. As a result, the anti-cancer drugs bortezomib, carfilzomib, and ixazomib targeting the 26S proteasome were developed to treat multiple myeloma, mantle cell lymphoma, and diffuse large B-cell lymphoma, among others. Despite success, adverse side effects and drug resistance are prominent, raising the need for alternative therapeutic options. We recently demonstrated that knockdown of the 19S regulatory components, 26S proteasome non-ATPase subunits 1 (PSMD1) and 3 (PSMD3), resulted in increased apoptosis of chronic myeloid leukemia (CML) cells, but had no effect on normal controls, suggesting they may be good targets for therapy. Therefore, we hypothesized that PSMD1 and PSMD3 are potential targets for anti-cancer therapeutics and that their relevance stretches beyond CML to other types of cancers. In the present study, we analyzed PSMD1 and PSMD3 mRNA and protein expression in cancerous tissue versus normal controls using data from The Cancer Genome Atlas (TCGA) and the Clinical Proteomic Tumor Analysis Consortium (CPTAC), comparing expression with overall survival. Altogether, our data suggest that PSMD1 and PSMD3 may be novel putative targets for cancer prognosis and therapy that are worthy of future investigation.

Rate of Second Primary Head and Neck Cancer With Cannabis Use

Objective To determine whether there is an association between cannabis use and developing a second primary cancer in head and neck cancer patients, as well as determining the prevalence of cannabis use amongst head and neck cancer patients. Study design This retrospective cohort study investigated patients from the Hamilton Region Head and Neck Cancer Database who were enrolled prospectively between 2011 and 2015, with follow-up data up to November 2018. Patients were contacted to confirm current cannabis and tobacco smoking status. Setting All patients were enrolled from a single tertiary cancer center in Hamilton, Ontario. Subjects and methods Consecutive patients with a newly diagnosed head and neck cancer were prospectively enrolled between 2011 to 2015. Cannabis users and controls were compared using standard modes of comparison. The odds ratio from a multivariable logistic regression model was then determined. Results A total of 513 patients were included in this study: 59 in the cannabis group and 454 in the control group. In terms of baseline characteristics, there was no significant difference between cannabis users and controls except that cannabis users were more likely to develop primary oropharyngeal cancer (p=0.0046). Two of 59 (3.4%) cannabis users developed a second primary cancer, in comparison to 23 of 454 (5.1%) non-cannabis users. The odds ratio for cannabis use on the second primary cancer was 0.19 (95% CI [0.01-3.20], p=0.25). Conclusion This study suggests that cannabis use behaves differently than tobacco smoking, as the former may not be associated with field cancerization.

Roundtable Discussion III: The Development and Uses of Artificial Intelligence in Medicine: A Work in Progress

Humans have devised machines to replace computation by individuals since ancient times: The abacus predated the written Hindu–Arabic numeral system by centuries. We owe a quantum leap in the development of machines to help problem solve to the British mathematician Charles Babbage who built what he called the Difference Engine in the mid-19th century. But the Turing formula created in 1936 is the foundation for the modern computer; it produced printed symbols on paper tape that listed a series of logical instructions. Three decades later, Olivetti manufactured the first mass-marketed desktop computer (1964), and by 1981, IBM had developed the first personal computer. Computing machines have become more and more powerful, culminating recently in Google’s claim that it had achieved quantum supremacy in developing a system that can complete a task in 200 seconds that it would take the most powerful type of classical computer available 10 000 years to achieve. In short, we are in a period of human history in which we are creating more and more powerful and complex machines potentially capable of duplicating human intelligence and indeed surpassing/expanding its power. We are solidly in the age of artificial intelligence (AI). Increasing interest in the development of AI and its application to human health at all levels makes a roundtable discussion by experts a valuable project for publication in our journal, Gender and the Genome, the official journal of the Foundation for Gender-Specific Medicine and the International Society of Gender Medicine.

Intrauterine human chorionic gonadotropin infusion in oocyte donors promotes endometrial synchrony and induction of early decidual markers for stromal survival: a randomized clinical trial

STUDY QUESTION

Does a single intrauterine infusion of human chorionic gonadotropin (hCG) at the time corresponding to a Day 3 embryo transfer in oocyte donors induce favorable molecular changes in the endometrium for embryo implantation?

SUMMARY ANSWER

Intrauterine hCG was associated with endometrial synchronization between endometrial glands and stroma following ovarian stimulation and the induction of early decidual markers associated with stromal cell survival.

WHAT IS KNOWN ALREADY

The clinical potential for increasing IVF success rates using an intrauterine hCG infusion prior to embryo transfer remains unclear based on previously reported positive and non-significant findings. However, infusion of CG in the non-human primate increases the expression of pro-survival early decidual markers important for endometrial receptivity, including α-smooth muscle actin (α-SMA) and NOTCH1.

STUDY DESIGN, SIZE, DURATION

Oocyte donors (n=15) were randomly assigned to receive an intrauterine infusion of 500 IU hCG (n=7) or embryo culture media vehicle (n=8) 3 days following oocyte retrieval during their donor stimulation cycle. Endometrial biopsies were performed 2 days later, followed by either RNA isolation or tissue fixation in formalin and paraffin embedding.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Reverse transcription of total RNA from endometrial biopsies generated cDNA, which was used for analysis in the endometrial receptivity array (ERA; n = 5/group) or quantitative RT-PCR to determine relative expression of ESR1, PGR, C3 and NOTCH1. Tissue sections were stained with hematoxylin and eosin followed by blinded staging analysis for dating of endometrial glands and stroma. Immunostaining for ESR1, PGR, α-SMA, C3 and NOTCH1 was performed to determine their tissue localization.

MAIN RESULTS AND THE ROLE OF CHANCE

Intrauterine hCG infusion was associated with endometrial synchrony and reprograming of stromal development following ovarian stimulation. ESR1 and PGR were significantly elevated in the endometrium of hCG-treated patients, consistent with earlier staging. The ERA did not predict an overall positive impact of intrauterine hCG on endometrial receptivity. However, ACTA2, encoding α-SMA was significantly increased in response to intrauterine hCG. Similar to the hCG-treated non-human primate, sub-epithelial and peri-vascular α-SMA expression was induced in women following hCG infusion. Other known targets of hCG in the baboon were also found to be increased, including C3 and NOTCH1, which have known roles in endometrial receptivity.

LIMITATIONS, REASONS FOR CAUTION

This study differs from our previous work in the hCG-treated non-human primate along with clinical studies in infertile patients. Specifically, we performed a single intrauterine infusion in oocyte donors instead of either continuous hCG via an osmotic mini-pump in the baboon or infusion followed by blastocyst-derived hCG in infertile women undergoing embryo transfer. Therefore, the full impact of intrauterine hCG in promoting endometrial receptivity may not have been evident.

WIDER IMPLICATIONS OF THE FINDINGS

Our findings suggest a potential clinical benefit for intrauterine hCG prior to embryo transfer on Day 3 in counteracting endometrial dyssynchrony from ovarian stimulation and promoting expression of markers important for stromal survival. Finally, there were no obvious negative effects of intrauterine hCG treatment.

STUDY FUNDING/COMPETING INTERESTS

Funding for this work was provided by NICHD R01 HD042280 (A.T.F.) and NICHD F30 HD082951 (M.R.S.). C.S. and P.D.-G are co-inventors of the patented ERA, which is owned by IGENOMIX SL and was used in this study, and C.S. is a shareholder in IGENOMIX SL. M.R.-A. is employed by IGENOMIX SL. No other authors have any conflicts of interest to report.

TRIAL REGISTRATION NUMBER

This study was registered with ClinicalTrials.gov (NCT01786252).

TRIAL REGISTRATION DATE

5 February 2013.

DATE OF FIRST PATIENT'S ENROLLMENT

10 May 2013.

Students' reflections on the relationships between safe learning environments, learning challenge and positive experiences of learning in a simulated GP clinic

Learning environments are a significant determinant of student behaviour, achievement and satisfaction. In this article we use students' reflective essays to identify key features of the learning environment that contributed to positive and transformative learning experiences. We explore the relationships between these features, the students' sense of safety in the learning environment (LE), the resulting learning challenge with which they could cope and their positive reports of the experience itself. Our students worked in a unique simulation of General Practice, the Safe and Effective Clinical Outcomes clinic, where they consistently reported positive experiences of learning. We analysed 77 essays from 2011 and 2012 using an immersion/crystallisation framework. Half of the students referred to the safety of the learning environment spontaneously. Students described deep learning experiences in their simulated consultations. Students valued features of the LE which contributed to a psychologically safe environment. Together with the provision of constructive support and immediate, individualised feedback this feeling of safety assisted students to find their own way through clinical dilemmas. These factors combine to make students feel relaxed and able to take on challenges that otherwise would have been overwhelming. Errors became learning opportunities and students could practice purposefully. We draw on literature from medical education, educational psychology and sociology to interpret our findings. Our results demonstrate relationships between safe learning environments, learning challenge and powerful learning experiences, justifying close attention to the construction of learning environments to promote student learning, confidence and motivation.

Flow-induced 2D protein crystallization: characterization of the coupled interfacial and bulk flows

Two-dimensional crystallization of the protein streptavidin, crystallizing below a biotinylated lipid film spread on a quiescent air-water interface is a well studied phenomenon. More recently, 2D crystallization induced by a shearing interfacial flow has been observed at film surface pressures significantly lower than those required in a quiescent system. Here, we quantify the interfacial and bulk flow associated with 2D protein crystallization through numerical modeling of the flow along with a Newtonian surface model. Experiments were conducted over a wide range of conditions resulting in a state diagram delineating the flow strength required to induce crystals for various surface pressures. Through measurements of the velocity profile at the air-water interface, we found that even in the cases where crystals are formed, the macroscopic flow at the interface is well described by the Newtonian model. However, the results show that even in the absence of any protein in the system, the viscous response of the biotinylated lipid film is complicated and strongly dependent on the strength of the flow. This observation suggests that the insoluble lipid film plays a key role in flow-induced 2D protein crystallization.

Design and evaluation techniques for authoring interactive and stylistic behaviors

We present a series of projects for end-user authoring of interactive robotic behaviors, with a particular focus on the style of those behaviors: we call this approach Style-by-Demonstration (SBD). We provide an overview introduction of three different SBD platforms: SBD for animated character interactive locomotion paths, SBD for interactive robot locomotion paths, and SBD for interactive robot dance. The primary contribution of this article is a detailed cross-project SBD analysis of the interaction designs and evaluation approaches employed, with the goal of providing general guidelines stemming from our experiences, for both developing and evaluating SBD systems. In addition, we provide the first full account of our Puppet Master SBD algorithm, with an explanation of how it evolved through the projects.

Four pi calibration and modeling of a bare germanium detector in a cylindrical field source

In this paper we describe a 4π cylindrical field acquisition configuration surrounding a bare (unshielded, uncollimated) high purity germanium detector. We perform an efficiency calibration with a flexible planar source and model the configuration in the 4π cylindrical field. We then use exact calculus to model the flux on the cylindrical sides and end faces of the detector. We demonstrate that the model accurately represents the experimental detection efficiency compared to that of a point source and to Monte Carlo N-particle (MCNP) calculations of the flux. The model sums over the entire source surface area and the entire detector surface area including both faces and the detector's cylindrical sides. Agreement between the model and both experiment and the MCNP calculation is within 8%.

Specific caspase interactions and amplification are involved in selective neuronal vulnerability in Huntington's disease

Huntington's disease (HD) is an autosomal dominant progressive neurodegenerative disorder resulting in selective neuronal loss and dysfunction in the striatum and cortex. The molecular pathways leading to the selectivity of neuronal cell death in HD are poorly understood. Proteolytic processing of full-length mutant huntingtin (Htt) and subsequent events may play an important role in the selective neuronal cell death found in this disease. Despite the identification of Htt as a substrate for caspases, it is not known which caspase(s) cleaves Htt in vivo or whether regional expression of caspases contribute to selective neuronal cells loss. Here, we evaluate whether specific caspases are involved in cell death induced by mutant Htt and if this correlates with our recent finding that Htt is cleaved in vivo at the caspase consensus site 552. We find that caspase-2 cleaves Htt selectively at amino acid 552. Further, Htt recruits caspase-2 into an apoptosome-like complex. Binding of caspase-2 to Htt is polyglutamine repeat-length dependent, and therefore may serve as a critical initiation step in HD cell death. This hypothesis is supported by the requirement of caspase-2 for the death of mouse primary striatal cells derived from HD transgenic mice expressing full-length Htt (YAC72). Expression of catalytically inactive (dominant-negative) forms of caspase-2, caspase-7, and to some extent caspase-6, reduced the cell death of YAC72 primary striatal cells, while the catalytically inactive forms of caspase-3, -8, and -9 did not. Histological analysis of post-mortem human brain tissue and YAC72 mice revealed activation of caspases and enhanced caspase-2 immunoreactivity in medium spiny neurons of the striatum and the cortical projection neurons when compared to controls. Further, upregulation of caspase-2 correlates directly with decreased levels of brain-derived neurotrophic factor in the cortex and striatum of 3-month YAC72 transgenic mice and therefore suggests that these changes are early events in HD pathogenesis. These data support the involvement of caspase-2 in the selective neuronal cell death associated with HD in the striatum and cortex.

Handsewn or stapled esophagogastric anastomoses after esophagectomy for cancer: meta-analysis of randomized controlled trials

Gastric transposition with esophagogastric anastomosis is a common method of reconstruction after esophagectomy for cancer. The anastomosis can be fashioned using a handsewn or stapled technique. The choice of anastomotic technique is often debated but there is little evidence to support the use of one method over the other. We performed a meta-analysis of randomized controlled trials (RCTs) to determine the effect of esophagogastric anastomotic method (handsewn or circular stapled) on patient outcomes. Medline and manual searches were done (completed independently and in duplicate) to identify all published RCTs that addressed the issue of handsewn or stapled esophagogastric anastomosis after esophagectomy for cancer. The selection process was inclusive; no trials were excluded. Trial validity assessment was done and a trial quality score was assigned. Major outcomes for quantitative data synthesis included operative mortality, anastomotic leaks, anastomotic strictures, cardiac morbidity, and pulmonary morbidity. A random-effects model was used and relative risk was the principal measure of effect. Systematic qualitative review was used for other outcomes such as duration of operation and time to complete the anastomosis. Data on cancer survival were not available in the RCTs. Five RCTs were selected with quality scores ranging from 2 to 3 (5-point Jadad scale). Selection and validity agreement was strong. Relative risk (95% confidence interval, CI; P-value), expressed as handsewn vs. stapled (treatment vs. control), was 0.45 (0.20, 1.00; P=0.05) for operative mortality, 0.79 (0.44, 1.42; P=0.43) for anastomotic leaks, 0.60 (0.27, 1.33; P=0.21) for anastomotic strictures, 0.99 (0.55, 1.77; P=0.97) for cardiac morbidity, and 0.93 (0.63, 1.37; P=0.72) for pulmonary morbidity. Data synthesized from existing RCTs show that handsewn and circular stapled esophagogastric anastomotic techniques give similar results for anastomotic outcomes, such as leaks and strictures. The stapled anastomotic method appears to increase operative mortality (P=0.05). Although it is difficult to explain this finding, it should not be dismissed. Several hypotheses are discussed.

A multiple schedule model of limited access drinking in the cynomolgus macaque

The present study reports on the development of a multiple schedule procedure of oral ethanol self-administration in cynomolgus macaques. Six adult cynomolgus macaques (four female, two male) were trained to self-administer ethanol and water under a 60 min, four-component multiple schedule of ethanol and water access with 1 g food pellets presented every 900 s (fixed-time 900 s). Water was available for the first and third 15 min components, ethanol in the second and fourth components. Total ethanol dose was stable at between 1-1.25 g/kg at ethanol concentration of 4%, 6% and 8%. Subsequently water was replaced with a sweetened drink (sugar-free Tang powder, General Foods). Ethanol and Tang were self-administered in similar volumes and both served as reinforcers compared with water. Acute pretreatment with 0.25 to 1.5 g/kg of intragastrically gavaged (i.g.) ethanol failed to alter ethanol or Tang self-administration significantly despite producing mean blood ethanol levels of up to 199 mg/dl when combined with self-administered ethanol. However, 1.0 g/kg i.g. ethanol administered for 15 consecutive days significantly decreased ethanol self-administration by 23%. The results suggest that ethanol self-administration under a multiple schedule is insensitive to alteration by acute ethanol pretreatment, but can be decreased by more prolonged chronic ethanol pretreatment.

Survival after conservative (palliative) management of pleural malignant mesothelioma

BACKGROUND AND OBJECTIVES

Malignant mesothelioma is a lethal disease. Aggressive multimodality treatment protocols are reportedly associated with improved survival, but the apparent survival benefits may simply reflect patient selection and the variable natural history of this malignancy. Before embarking on our own protocol of experimental treatment for mesothelioma, we sought to identify important prognostic factors and document the survival of patients treated conservatively (with palliative intent only) in our region.

METHODS

We performed a retrospective review of all patients with a diagnosis of malignant mesothelioma seen at our center between 1987 and 1999. Since curative intent treatment had not been given, we assumed that measured survival would largely reflect the natural history of the malignancy.

RESULTS

There were 101 patients (80 males and 21 females). Mean age was 65 +/- 9.2 years. Symptoms of disease were present for a median time of 5 months before the diagnosis was established. The most common presenting symptoms were dyspnea (46 patients), chest pain (30 patients), and weight loss (22 patients). Sixty-eight patients (68%) had a history of asbestos exposure. Mesothelioma subtypes included epithelial (43 patients), sarcomatous (26 patients), mixed (19 patients), desmoplastic (4 patients), and unspecified (9 patients). All 101 patients were treated with palliative intent. Talc pleurodesis was performed in 70 patients. At the time of analysis, 90 patients had died and 11 remained alive. Median survival was 213 (95% CI 137-289) days. Survival for the three major histological subtypes was significantly different (log rank, P = 0.0016). Histological subtype (epithelial favorable) was the only significant independent prognostic factor (Cox proportional hazard regression, P = 0.0009).

CONCLUSIONS

Patients with epithelial mesothelioma survive longer than those with other histological subtypes. Conservatively managed patients with pleural malignant mesothelioma have a median survival of approximately 7 months. These data from conservatively treated patients can serve as baseline information for future studies of experimental treatments.

A meta-analysis of randomized controlled trials of route of reconstruction after esophagectomy for cancer

BACKGROUND

A gastric conduit is usually used to reconstruct the foregut after esophagectomy for cancer. It can be transposed through a posterior or anterior mediastinal route. The choice of route is often debated but there is little evidence to support the use of one route over the other. We performed a meta-analysis of randomized controlled trials (RCTs) to determine the effect of route of reconstruction on patient outcomes.

METHODS

Medline and manual searches were done (completed independently and in duplicate) to identify all published RCTs that addressed the issue of route of gastric conduit reconstruction after esophagectomy for cancer. The selection process was inclusive; no trials were excluded. Trial validity assessment was done and a trial quality score was assigned. Major outcomes for quantitative data synthesis included operative mortality, anastomotic leaks, cardiac morbidity, and pulmonary morbidity. A random-effects model was used and relative risk was the principal measure of effect. Systematic qualitative review was used for other outcomes such as duration of ventilation, length of hospital stay, operative blood loss, duration of surgery, anastomotic strictures, dysphagia, gastric emptying, and quality of life. Data on cancer survival were not available in the RCTs.

RESULTS

Six RCTs were selected with quality scores ranging from 1 to 4 (5-point Jadad scale). Selection and validity agreement was strong. Relative risk (95% confidence interval; P value), expressed as posterior versus anterior mediastinal route (treatment versus control), was 0.56 (0.17, 1.82; P = 0.34) for mortality, 1.01 (0.35, 2.94; P = 0.98) for leaks, 0.43 (0.17, 1.12; P = 0.08) for cardiac complications, and 0.67 (0.34, 1.33; P = 0.26) for pulmonary complications. Systematic qualitative review did not suggest any difference in other perioperative outcomes or conduit function for the two routes of reconstruction.

CONCLUSIONS

Data synthesized from existing RCTs show that posterior and anterior mediastinal routes of reconstruction are associated with similar outcomes after esophagectomy for cancer. However, a difference in outcomes for the two reconstructive routes remains possible. Further trials with larger numbers of patients are needed.

Potassium repletion fails to interfere with reduction of serum lithium by sodium polystyrene sulfonate in mice

OBJECTIVES

Previous studies have shown that oral sodium polystyrene sulfonate (SPS) lowers serum lithium concentrations after acute and chronic toxic lithium exposures. Because hypokalemia may represent a deterrent to the clinical use of SPS for lithium intoxication, this study was designed to determine whether potassium (K+) repletion interferes with the effect of SPS on serum lithium.

METHODS

168 male, CD-1 mice were given lithium chloride (LiCl) (250 mg/kg) by gavage at time 0. Half of the mice were then given SPS (5 g/kg/dose) and half an equivalent volume of water by gavage at times 20 and 40 minutes. Half of each of these subgroups was then given potassium chloride (KCl) (3 mmol/kg) intraperitoneally and half an equivalent volume of normal saline. The animals were then sacrificed at one, two, four, and eight hours after lithium administration and the sera were analyzed for lithium and K+ by atomic absorption spectrophotometry. The groups were compared with analysis of variance.

RESULTS

The SPS lowered both lithium and K+ concentrations (ps < or = 0.0001). The KCl treatment was associated with transiently increased K+ concentrations (p < 0.0001) and with mildly elevated lithium concentrations when compared with the results of the animals not treated with KCl (p = 0.0016). The KCl treatment-associated increase in lithium concentration occurred both in the animals treated with water and in those treated with SPS.

CONCLUSIONS

Potassium repletion did not interfere with the ability of SPS to lower serum lithium concentration in animals experimentally poisoned with lithium.

Diversity, genetic structure and evidence of outcrossing in British populations of the rock fern Adiantum capillus-veneris using microsatellites

Microsatellites were isolated and a marker system was developed in the fern Adiantum capillus-veneris. Polymorphic markers were then used to study the genetic diversity and structure of populations within the UK and Ireland where this species grows at the northern edge of its range, requiring a specific rock habitat and limited to a few scattered populations. Three dinucleotide loci detected a high level of diversity (23 alleles and 28 multilocus genotypes) across the UK and Ireland, with nearly all variation partitioned among rather than within populations. Of 17 populations represented by multiple samples, all except four were monomorphic. Heterozygosity was detected in three populations, all within Glamorgan, Wales (UK), showing evidence of outcrossing. We make inferences on the factors determining the observed levels and patterns of genetic variation and the possible evolutionary history of the populations.

Induction and maintenance of ethanol self-administration in cynomolgus monkeys (Macaca fascicularis): long-term characterization of sex and individual differences

BACKGROUND

Investigations of oral ethanol self-administration in nonhuman primates have revealed important parallels with human alcohol use and abuse, yet many fundamental questions concerning the individual risk to, and the biological basis of, excessive ethanol consumption remain unanswered. Moreover, many conditions of access to ethanol in nonhuman primate research are largely unexplored. This set of experiments extends within- and across-session exposure to ethanol to more fully characterize individual differences in oral ethanol self-administration.

METHODS

Eight male and eight female adult cynomolgus monkeys (Macaca fascicularis) were exposed to daily oral ethanol self-administration sessions for approximately 9 months. During the first 3 months, a fixed-time (FT) schedule of food delivery was used to induce the consumption of an allotted dose of ethanol in 16-hr sessions. Subsequently, the FT schedule was suspended, and ethanol was available ad libitum for 6 months in 16- or 22-hr sessions.

RESULTS

Cynomolgus monkeys varied greatly in their propensity to self-administer ethanol, with sex and individual differences apparent within 10 days of ethanol exposure. Over the last 3 months of ethanol access, individual average ethanol intakes ranged from 0.6 to 4.0 g/kg/day, resulting in blood ethanol concentrations from 5 to 235 mg/dl. Males drank approximately 1.5-fold more than females. In addition, heavy-, moderate-, and light-drinking phenotypes were identified by using daily ethanol intake and the percentage of daily calories obtained from ethanol as criteria.

CONCLUSIONS

Cynomolgus monkeys displayed a wide intersubject range of oral ethanol self-administration with a procedure that used a uniform and prolonged induction that restricted early exposure to ethanol and subsequently allowed unlimited access to ethanol. There were sex and stable individual differences in the propensity of monkeys to consume ethanol, indicating that this species will be important in characterizing risk factors associated with heavy-drinking phenotypes.

Anastomotic leaks after esophagectomy for esophageal cancer: a comparison of thoracic and cervical anastomoses

BACKGROUND AND OBJECTIVES

Esophagogastric anastomotic leaks remain a significant problem after esophagectomy for esophageal cancer. Many investigators have reported that leaks are more frequent after cervical, as opposed to thoracic, esophagogastric anastomoses. We conducted a retrospective review to assess the effect of anastomotic location (thoracic or cervical) on anastomotic leak incidence and severity.

METHODS

Seventy-four consecutive patients with esophageal cancer underwent esophagectomy and esophagogastric anastomoses at our institution over a four-year period. Their charts were reviewed retrospectively and data was collected on age, gender, histology, stage, resection margin status, adjuvant therapy, cancer survival, anastomotic location, anastomotic leaks, and operative mortality.

RESULTS

Cervical anastomoses were done in 19 patients and thoracic anastomoses were done in the other 55 patients. The two groups were similar with respect to age, gender, histology, stage, adjuvant therapy, and overall survival. Operative mortality for the entire group of 74 patients was 4% (3 patients). Resection margins were positive for residual tumor in 2 of 19 (11%) patients with cervical anastomoses and 9 of 55 (16%) patients with thoracic anastomoses (p=0.42). Leaks complicated 1 of 19 (5%) cervical and 9 of 55 (16%) thoracic esophagogastric anastomoses (p=0.21). Positive resection margins and anastomotic leaks were not significantly related (p=0.54). One of 9 (11%) leaks in the thoracic group proved fatal.

CONCLUSIONS

In our experience cervical esophagogastric anastomoses do not have a higher incidence of leaks than thoracic anastomoses.

Local recurrence after total or subtotal esophagectomy for esophageal cancer

Cancer recurrence is a common problem after esophagectomy for esophageal cancer. Local recurrence is especially problematic because it often negates the palliative benefit of esophagectomy. We conducted a retrospective review to assess the effect of extent of esophageal resection (subtotal or total esophagectomy) on local cancer recurrence. Seventy-four consecutive patients with esophageal cancer underwent esophagectomy at our institution over a four-year period. Their charts were reviewed retrospectively and data was collected on age, gender, histology, stage, tumor location, operation, resection margin status, anastomotic leaks, operative mortality, adjuvant therapy, cancer survival, and local recurrence. Total esophagectomy was done in 19 patients (transhiatal - 3; McKeown - 16) and subtotal esophagectomy was done in the other 55 patients (Lewis - 25; left thoracoabdominal - 30). The two groups were similar with respect to age, gender, histology, stage, anastomotic leaks, operative mortality, adjuvant therapy, and overall survival. Resection margins were positive for residual tumor in 2 out of 19 (11%) total esophagectomies and 9 out of 55 (16%) subtotal esophagectomies (p=0.42). Local recurrence occurred in 3 of 19 (16%) patients treated with total esophagectomy and 23 out of 55 (42%) patients treated with subtotal esophagectomy (p=0.04). We conclude that total esophagectomy is associated with fewer local cancer recurrences than subtotal esophagectomy. We, therefore, recommend total esophagectomy for the surgical treatment of esophageal cancer.

Prophylactic intracavitary (pneumonectomy space) antibiotic instillation: a comparative study

BACKGROUND AND OBJECTIVES

Postpneumonectomy empyema is a dreaded complication of pneumonectomy. The effectiveness of prophylactic intracavitary antibiotic instillation is not known. We conducted a retrospective review to assess the effect of pneumonectomy space antibiotic instillation on septic complications (empyema and bronchial fistula) of pneumonectomy.

METHODS

Ninety-three consecutive patients underwent pneumonectomy at our institution over a three-year period. Their charts were reviewed retrospectively and data was collected on age, gender, diagnosis, intravenous antibiotics, intracavitary (pneumonectomy space) antibiotics, empyemas, bronchial fistulas, length of hospital stay, and operative mortality.

RESULTS

All 93 patients received 3 perioperative doses of prophylactic intravenous antibiotics. One group (n=47) of patients also received intraoperative intracavitary instillation of an antibiotic solution (penicillin G: 5 million units, bacitracin: 50,000 units, gentamicin: 60 mg, in 1 litre of saline) while the other group (n=46) did not. Age, gender, diagnosis, and length of stay were not significantly different in the two groups. There were no empyemas or bronchial fistulas in the intracavitary antibiotic group. Postpneumonectomy empyemas occurred in 6 (13%) patients (empyema with bronchial fistula: 5, empyema alone: 1) that had not received intracavitary antibiotics (p=0.012). There were 4 deaths (9%) in each group (p=0.63).

CONCLUSIONS

Prophylactic intraoperative intracavitary antibiotic instillation may reduce the incidence of empyemas after pneumonectomy. However, a randomized trial would be needed to prove the effectiveness of this form of prophylactic antibiotic strategy.

Colorectal cancer screening by primary care physicians in Texas: a rural-urban comparison

BACKGROUND

Little is known about colorectal cancer (CRC) screening practices of primary care physicians (PCPs) in rural versus urban locations.

METHODS

The authors surveyed 3,380 PCP members of the Texas Medical Association (TMA), stratified by specialty and rural/urban status. Factors associated with PCPs' self-reported practices of CRC screening by fecal occult blood test (FOBT) and/or flexible sigmoidoscopy (SIG) were examined using chi-square tests and multivariate regression.

RESULTS

Over 80% of both rural and urban PCPs reported CRC screening with the FOBT, while 70% reported screening with SIG. Many reported doing FOBTs in the office versus using the take-home kit. Variations were found in recommended ages and screening intervals among all respondents.

CONCLUSIONS

Geographic location was less important than knowledge and attitudes in predicting PCPs' CRC screening practices. More specific education regarding CRC screening guidelines needs to be directed towards all PCPs.

Comparison of videothoracoscopy and axillary thoracotomy for the treatment of spontaneous pneumothorax

Surgical treatment of spontaneous pneumothorax can be done through a thoracotomy or a video-thoracoscopic approach. Although the videothoracoscopic technique is currently popular it is not obviously superior to a more traditional axillary thoracotomy approach. We compared our recent experience with both techniques to determine the optimal surgical treatment for spontaneous pneumothoraces. A retrospective review of 79 patients treated surgically (34 thoracotomy and 45 thoracoscopy) for spontaneous pneumothoraces was done. Patients were treated between 1991 and 1997. Patients older than 60 years of age and those with spontaneous pneumothoraces secondary to generalized pulmonary emphysema were excluded. There were no operative deaths. Recurrence rate [thoracotomy, two of 34; thoracoscopy, three of 45 (P < 0.89)], air leak exceeding 7 days [thoracotomy, three of 34; thoracoscopy, three of 45 (P < 0.73)], operating room times [thoracotomy, 54 +/- 26 minutes; thoracoscopy, 53 +/- 16 minutes (P < 0.59)], and postoperative length of stay [thoracotomy, 5.7 +/- 4.3 days; thoracoscopy, 4.7 +/- 4.4 days (P < 0.26)] were not significantly different for the two techniques. We conclude that axillary thoracotomy and videothoracoscopy are equally effective surgical treatments for spontaneous pneumothoraces. A large randomized trial would be needed to determine whether one approach is truly superior to the other.

A randomized, controlled trial comparing thoracoscopy and limited thoracotomy for lung biopsy in interstitial lung disease

BACKGROUND

Lung biopsies are frequently needed to diagnose diffuse interstitial lung diseases. A prospective randomized, controlled trial comparing limited thoracotomy (open lung biopsy) and thoracoscopy for lung biopsy was done.

METHODS

Ambulatory patients with a clinical diagnosis of diffuse interstitial lung disease were randomized to thoracoscopy or limited thoracotomy. Data on postoperative pain, narcotic requirements, operating room time, adequacy of biopsy, duration of chest tube drainage, length of hospital stay, spirometry, and complications were collected.

RESULTS

A total of 42 randomized patients underwent lung biopsy (thoracoscopy 20, thoracotomy 22). The two study groups were comparable with respect to age, gender, corticosteroid use, and preoperative spirometry. Visual analog scale pain scores were nearly identical in the two groups (p = 0.397). Total morphine dose was 50.8 +/- 27.3 mg in the thoracoscopy group and 52.5 +/- 25.6 mg in the thoracotomy group (p = 0.86). Spirometry (FEV1) values in the two groups were not significantly different on postoperative days 1, 2, 14, and 28 (p = 0.665). Duration of operation was similar in both groups (thoracoscopy 40 +/- 30 minutes, thoracotomy 37 +/- 15 minutes; p = 0.67). The thoracoscopy and thoracotomy groups had equivalent duration of chest tube drainage (thoracoscopy 38 +/- 28 hours, thoracotomy 31 +/- 26 hours; p = 0.47) and length of hospital stay (thoracoscopy 77 +/- 82 hours, thoracotomy 69 +/- 55 hours; p = 0.72). Definitive pathologic diagnoses were made in all patients.

CONCLUSIONS

There is no clinical or statistical difference in outcomes for thoracoscopic and thoracotomy approaches. Both thoracoscopy and thoracotomy are acceptable procedures for diagnostic lung biopsy in diffuse interstitial lung disease.

Imaging features of primary and recurrent esophageal cancer at FDG PET

Because of the poor prognosis for patients with esophageal cancer and the risks associated with surgical intervention, accurate staging is essential for optimal treatment planning. Positron emission tomography (PET) with 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) is a useful adjunct to more conventional imaging modalities in this setting. FDG PET is not an appropriate first-line diagnostic procedure in the detection of esophageal cancer and is not helpful in detecting local invasion by the primary tumor, and further studies are required to determine its efficacy in the detection of local nodal metastases. However, FDG PET is superior to anatomic imaging modalities in the ability to detect distant metastases. Metastases to the liver, lungs, and skeleton can readily be identified at FDG PET. In addition, FDG PET has proved valuable in determining the resectability of disease and allows scanning of a larger volume than is possible with computed tomography. Recurrent disease is readily diagnosed and differentiated from scar tissue with FDG PET. In addition, FDG PET may play a valuable role in the follow-up of patients who undergo chemotherapy and radiation therapy, allowing early changes in treatment for unresponsive tumors. The management of most patients with esophageal cancer can be improved with use of FDG PET.

Human ovarian follicular fluid has functional systems for the generation and modulation of thrombin

OBJECTIVE

To determine whether prothrombin is present in follicular fluid and whether the enzymatic pathways for prothrombin activation are similar to those in plasma.

DESIGN

Follicular fluid samples collected at the time of oocyte harvest for an assisted reproductive technology procedure (ART) were analyzed for a panel of hemostatic proteins with use of a combination of functional, chromogenic, and Western ligand blot analysis.

SETTING

An ART clinic and an academic research laboratory.

PATIENT(S)

Women undergoing ART.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Determination of components of thrombin generation and thrombin modulatory systems using functional and antigenic assay procedures.

RESULT(S)

Both prothrombin and components of the prothrombinase enzyme complex, which includes factors V, VII, and X, are present in follicular fluid. Other hemostatic proteins, including factors VIII and IX and vonWillebrand factor, are absent. The direct activation of prothrombin to thrombin is similar in follicular fluid and plasma. Like plasma, inhibitors of both thrombin and thrombin generation, including antithrombin, protein C, and alpha2-macroglobulin, are present in follicular fluid.

CONCLUSION(S)

Only a select group of hemostatic plasma proteins are present in follicular fluid. There is no direct correlation between molecular size and concentration of individual proteins in follicular fluid. These results indicate that the proteins involved in the thrombin-generating and thrombin modulatory pathways may be derived from ovarian cells, suggesting that thrombin may have a role in folliculogenesis.

Development of delirium: a prospective cohort study in a community hospital

BACKGROUND

Previous research on risk of delirium in acute hospital settings identified mainly patient variables (e.g., age) that are not amenable to intervention. The purpose of this study was to develop a model for new delirium in hospitalized older patients that included process of care and social variables.

METHODS

A prospective cohort study was undertaken in a community hospital in Ontario, Canada. Research participants included 156 hospitalized patients age 65+ years and without delirium on admission who were admitted to a medical or surgical unit. The measures included daily appraisal of delirium using a standardized and validated tool, and assessment of patient, process of care, and social variables.

RESULTS

Delirium developed in 28 of the 156 patients (17.9%). Older age and cognitive impairment were significant patient variables. Significant process of care variables included a high number of medications administered during hospitalization, surgery, a high number of procedures during early hospitalization (e.g., x-rays, blood tests), and intensive care treatment.

CONCLUSIONS

Approximately one older patient in five developed delirium after admission to a medical or surgical unit. Risks not easily amenable to intervention included age, cognitive dysfunction, surgery, and intensive care requirements. Risk factors that are potentially modifiable included number of medications and number of procedures. Future research might focus on the efficacy of such intervention to reduce new-onset delirium in acute hospital settings.

11-cis retinol dehydrogenase mutations as a major cause of the congenital night-blindness disorder known as fundus albipunctatus

PURPOSE

Patients with fundus albipunctatus uniformly experience difficulty with vision at night. Their retinas are spotted with characteristic light yellow flecks of unknown composition that typically spare the macula. A defect in the transport or utilization of visual cycle retinoids is thought to underlie this recessive disorder with variable clinical expression. To elucidate the molecular defect we considered the genes for interphotoreceptor retinoid-binding protein (RBP3) and 11-cis retinol dehydrogenase (RDH5) as candidates for this disease.

METHODS

We examined two unrelated families with fundus albipunctatus. The diagnosis was determined clinically and RBP3 and RDH5 were analyzed by molecular screening methods and direct genomic sequencing.

RESULTS

Each family had two affected members with typical fundus albipunctatus. The affected members were siblings born to unaffected parents who were seventh cousins in the first family and unrelated in the second family. The probands from both families were clinically similar except for the fundus dots that were more extensive in the second family to the point of involving the parafoveal region. In the initial phase of genetic screening RBP3 defects were ruled-out as the cause of the disease in both families. In contrast, RDH5 mutations were found in the affected siblings in both families. The proband in one had a homozygotic Gly238Trp missense mutation (GGG -> TGG) involving exon 4 and in the other carried compound heterozygotic changes Arg280His (CGC -> CAC) and Ala294Pro (GCC -> CCC) in exon 5. The disease phenotype was only manifested in family members with two abnormal RDH5 alleles consistent with autosomal recessive inheritance in both pedigrees.

CONCLUSIONS

These findings strongly implicate defects of RDH5 as the cause of fundus albipunctatus and point to a heterogeneity of RDH5 mutations in this form of congenital stationary night blindness with variable expressivity.

Oromandibular reconstruction with the radial-forearm osteocutaneous flap: experience with 60 consecutive cases

One of the more difficult problems in reconstructive surgery of the head and neck is replacement of bone and soft tissue lost because of injury, osteomyelitis, or malignancy. The radial-forearm osteocutaneous flap is an accepted choice for oromandibular reconstruction. This study was undertaken to review one center's experience with 60 consecutive cases of oromandibular reconstruction with the radial-forearm osteocutaneous flap. Records of the 38 men and 22 women (mean age, 60 years; range, 26 to 86 years) were reviewed for tumor location, defect and bone length, flap failure rate, recipient- and donor-site complications, length of surgery, and hospital stay. Cancer resection was the reason for 97 percent of reconstructions; 33 percent of flaps were used to reconstruct a lateral defect of the mandible, 40 percent a lateral-central defect, and 27 percent a lateral-central-lateral defect. Mean skin flap size was 55 cm2 (range, 15 to 117 cm2) and mean bone length, 9.4 cm (range, 5 to 14 cm). The microvascular success rate was 98.3 percent. Complications included fracture of the donor radius (15 percent), nonunion of the mandible (5 percent), and hematoma (8.3 percent). These results are comparable to results reported in the literature with other radial forearm flaps. The free radial osteocutaneous flap is a safe and reliable choice for mandibular reconstruction. It offers sufficient bone to reconstruct large defects and can provide adequate pedicle length for vessel anastomosis to the contralateral side of the neck. The above attributes make the radial forearm osteocutaneous flap one of the "first line" flap choices for oromandibular reconstruction.

Microsurgical reconstruction of the through-and-through defect in head and neck cancer: is it worth it?

As health resources diminish, there are compelling reasons to utilize health dollars in a fiscally responsible manner. The reconstruction of complex oromandibular defects involving mucosa, bone, and skin coverage poses one of the greatest challenges in microsurgery of the head and neck. The cancer patient who requires a through-and-through resection and microsurgical reconstruction usually has a poor prognosis. In this study, the authors examine whether this type of surgery is worthwhile in terms of cost, functional outcome, and patient satisfaction. Of 16 cases of through-and-through oromandibular reconstruction performed, the survival outcome of ten (n = 10) advanced cases requiring immediate oromandibular reconstruction (7 radial forearm flaps; 3 scapular flaps) is presented. Six cases were considered cured and required delayed reconstruction. Seven of the 10 patients died within 39 months postoperatively, while three survived up to 68 months postoperatively. The combined experience of these ten patients was examined using the Kaplan-Meier (product-limit) estimator of the survival curve. Results show that of the seven patients who died of disease, five did so within the first postoperative year. More important, among those five patients who survived for more than one postoperative year, three were still alive up to 68 months, representing a combined total of over 15 postoperative years. The probability of long-term survival is good in through-and-through oromandibular cancer patients who can survive to 1 year postoperatively, and it is proposed that microsurgical reconstruction, albeit costly, remains a worthwhile procedure,

A comparison of thoracic and lumbar epidural techniques for post-thoracoabdominal esophagectomy analgesia

PURPOSE

To compare thoracic epidural analgesia (TEA) using a bupivacaine/fentanyl mixture and lumbar epidural analgesia (LEA) with morphine, in respect to the time to extubation and the quality of post-operative analgesia, in patients having thoracoabdominal esophagectomy.

METHODS

Twenty two patients scheduled for elective thoracoabdominal esophagectomy were randomized to TEA or LEA. Postoperatively, the TEA group received Patient Controlled Epidural Analgesia (PCEA) with bupivacaine 0.125% and 5 microg x ml(BI) fentanyl, and the LEA group received PCEA with 0.2 microg x ml(BI) morphine. A blinded observer assessed criteria for tracheal extubation and the time of tracheal extubation was recorded. Early extubation was defined as tracheal extubation within four hours postoperatively. Visual analogue pain scores at rest (Static Visual Analogue Pain Scores, SVAPS) and with movement (Dynamic Visual Analogue Pain Scores, DVAPS) were recorded at 1, 6, 12, 18 and 24 hr post-extubation. Failure of the epidural protocol (FEP) was defined as a request for additional analgesia.

RESULTS

Tracheal extubation was achieved in 70% of the LEA and 100% of the TEA at four hours postoperatively (P=NS). However, the TEA group achieved earlier extubation times when assessed with log rank testing (P = 0.01). By six hours post-extubation FEP had occurred in 50% of the LEA group but in none of the TEA group (P = 0.01). Mean SVAPS and DVAPS were lower in the TEA than in the LEA group at all measured times (P < 0.01).

CONCLUSION

This study has demonstrated superior pain control in patients undergoing thoraco-abdominal esophagectomy treated with TEA than with LEA, particularly for pain with movement. Tracheal extubation occurred earlier in the TEA group, but this difference was not significant at four hours postoperatively.

Phospholipid fatty acyl spatial distribution in bovine rod outer segment disk membranes

The distribution of fatty acids within the phospholipid headgroup classes was investigated as a function of the age/spatial distribution of bovine rod outer segment disk membranes. The disks were separated into subpopulations based upon the cholesterol content in their membranes. Because disk membrane cholesterol content decreases as the disks are apically displaced in the rod outer segment, this separation yields disk subpopulations of different ages and from age-dependent spatial locations within the outer segment. The phospholipids, phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS) and phosphatidylinositol (PI), of each of these subpopulations were separated and the fatty acid composition of each was determined. These data indicated that while most of the fatty acids show little or no change with age/spatial location, some pronounced changes can be observed in certain classes. Within the PC class, 16:0 dramatically decreases with disk age while the 22:6 increases with disk age. While the PE class exhibits some fatty acid changes, they are small. The PS class exhibits no significant changes in fatty acid composition. The PI class which constitutes less than 2% of the total phospholipid exhibits age-related changes in each of the fatty acids which could be measured. Most notable of these is an increase in 20:4 as the disks are apically displaced. These changes indicate a remodeling of the disk membranes which may be related to the phototransduction process or to preparation for eventual disk phagocytosis.

Comparative study of continuous extrapleural intercostal nerve block and lumbar epidural morphine in post-thoracotomy pain

OBJECTIVES

To compare the efficacy of continuous extrapleural intercostal nerve block with bupivacaine 0.5% in 1:200,000 epinephrine and continuous lumbar epidural block with morphine in controlling post-thoracotomy pain and to measure serum bupivacaine concentrations during extrapleural infusion.

DESIGN

A prospective, randomized, controlled trial.

SETTING

St. Joseph's Hospital, Hamilton, Ont., a tertiary care teaching centre.

PATIENTS

Sixty-one patients booked for elective thoracotomy were randomized by scaled envelope to two groups.

INTERVENTIONS

Group A received a continuous extrapleural intercostal nerve block with bupivacaine 0.5% in 1:200,000 epinephrine as a bolus of 0.3 mL/kg followed by an infusion of 0.1 mL/kg every hour for 72 hours. Group B received a continuous lumbar epidural block with morphine as a bolus of 70 g/kg followed by an infusion of 7 g/kg every hour for 72 hours.

MAIN OUTCOME MEASURES

Pain was assessed by a linear visual analogue scale (VAS) pain score. The cumulative amount of "rescue" intravenous morphine used, and serum bupivacaine concentrations were measured as secondary outcomes.

RESULTS

Pain control was the same in both groups as assessed by linear VAS score (p = 0.33). The cumulative dose of intravenous morphine for supplemental analgesia was statistically significant between the groups: group A patients used more morphine than group B (p < 0.05). Accumulation of serum bupivacaine was present with no clinical toxicity.

CONCLUSIONS

There is no significant difference in the degree of post-thoracotomy pain control measured by the VAS score when analgesia is provided by continuous extrapleural intercostal nerve block with bupivacaine 0.5% in 1:200,000 epinephrine or lumbar epidural block with morphine. Larger amounts of rescue analgesia were used by patients in the continuous extrapleural group with bupivacaine than those in the continuous lumbar epidural block with morphine. Serum bupivacaine concentrations rise without clinical toxicity.

Serum bupivacaine concentrations during continuous extrapleural infusion

PURPOSE

To determine the rate of increase in serum bupivacaine concentration during continuous extrapleural infusion.

METHODS

After thoracotomy for lobectomy under general anaesthesia, nine patients had an extrapleural catheter inserted, before chest closure, in a costovertebral gutter constructed surgically by lifting the parietal pleural. Bupivacaine 0.5% with epinephrine 1:200.000 was injected through the catheter as 0.3 ml.kg-1 bolus followed by 0.1 ml.kg-1.hr-1 for five days. Serum bupivacaine (free and total), albumin, alpha-1 acid glycoprotein concentrations were measured 15 min after injection and at 24 hr intervals for five days. Bupivacaine concentrations were determined by column liquid chromatography using solid phase extraction. Serum alpha-1 acid glycoprotein concentration was determined by nephelometry on QM 300 protein analyzer. Serum albumin concentration was determined by bromocresol green dye binding procedure on Hitachi 717 Autoanalyzer.

RESULTS

A continuous elevation in total serum bupivacaine was observed, with an average value of 0.75 microgram.ml-1 on day 1 to 2.77 micrograms.ml-1 on day 4 (P < 0.05). There was no increase in postoperative free serum bupivacaine concentration; average value of 177 pcg.ml-1 on day 1 and 249 pcg.ml-1 on day 4 (P = 0.92). Postoperative serum alpha-1 acid glycoprotein concentration showed a steady rise with an average value of 0.94 microgram.ml-1 on day 1 and 1.47 micrograms.ml-1 on day 4 (P < 0.05). No change was observed in post-operative serum albumin with an average value of 31.4 g.l-1 on day 1 and 31.3 g.l-1 on day 4.

CONCLUSION

Continuous extrapleural infusion of bupivacaine over five days after thoracotomy is associated with a steady increase in total serum bupivacaine concentration and no elevation in free serum bupivacaine concentration.

[Treatment of borderline personality disorder with the schema-focused approach]

The treatment of Borderline Personality Disorder has been a challenge for Cognitive Therapy (CT): some modifications to the CT basic model had to be implemented in order to intervene with BPD patients. Young's schema-focused approach offers an intervention model which relies on early maladaptive schemas and modes concepts. According to this model, the BDP presents four dysfunctional modes: the Abandoned Child mode, the Detached Protector mode, the Punitive Parent mode, the Angry Child mode. The therapist must identify the presence of these modes and implement therapeutic strategies specific to each of them. There are four different kinds of therapeutic strategies: interpersonal (therapy relationship), experiential, cognitive and behavioral.

Interleukin-1 beta modulates prostaglandin and progesterone production by primate luteal cells in vitro

Increasing evidence suggests that cytokine products of the immune system may play a regulatory role in corpus luteum regulation in several species. The role of cytokines in primate luteal function, however, remains unclear. In the present study we examined the effects of interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF alpha), and interferon-gamma (IFN-gamma) on progesterone and prostaglandin (PGE2, PGF2 alpha) production by primate luteal cells in vitro. Specifically, corpora lutea were removed from normally cycling cynomolgus monkeys (n = 30 corpora lutea) during either the early (Days 3-5 after the estimated LH surge), mid (Days 8-10), or late (Days 12-14) luteal phase of the menstrual cycle. The corpora lutea were dispersed into individual cells using collagenase, DNase, and hyaluronidase. Approximately 50,000 viable luteal cells per tube were incubated in Ham's F-10 medium with increasing concentrations of IL-1 beta (0.1-10 ng/ml), TNF alpha (1-100 ng/ml), or IFN-gamma (10-1000 U/ml) in the presence and absence of hCG for 8 h at 37 degrees C. TNF alpha and IFN-gamma had no effect on progesterone PGE2, or PGF2 alpha production during any phase of the cycle at the doses tested. In contrast, IL-1 beta significantly stimulated PGF2 alpha production in a dose-dependent manner during the mid and late luteal phases (p < 0.05). Human CG alone had no effect on PGE2 or PGF2 alpha production by dispersed luteal cells in vitro but inhibited IL-1 beta-stimulated PGF2 alpha production. As expected, hCG stimulated progesterone production by primate luteal cells in vitro. Interestingly, IL-1 beta inhibited this hCG stimulation of progesterone production. In summary, these date suggest that IL-1 beta is a potentially important modulator of prostaglandin production by the primate corpus luteum. In view of this, cytokine-mediated changes in prostaglandin production by the primate corpus luteum may participate in the physiological regulation of luteal function.

Rhodopsin-cholesterol interactions in bovine rod outer segment disk membranes

Cholesterol modulates the function of rhodopsin in the retinal rod outer segment (ROS) disk membranes. One mechanism for such modulation is cholesterol modulation of the properties of the membrane bilayer. This has been explored previously. Another possible mechanism is an interaction between the sterol and the protein, which has not been previously explored. In this study, the fluorescent sterol, cholestatrienol, was used to probe interactions between cholesterol and rhodopsin in bovine ROS disk membranes. Cholestatrienol was incorporated into the disk membranes by exchange from donor phospholipid vesicles. Fluorescence energy transfer from protein tryptophans to cholestatrienol was observed indicating close approach of this fluorescent sterol to the tryptophan. The effectiveness of the energy transfer was measured by the quenching of tryptophan fluorescence by cholestatrienol. The quenching of tryptophan fluorescence was directly related to the cholestatrienol content of the membranes. Cholesterol was incorporated into the disk membranes by exchange from donor phospholipid vesicles. The effect of increasing membrane cholesterol on the ability of cholestatrienol to quench rhodopsin tryptophan fluorescence was determined. This quenching was inversely proportional to the membrane cholesterol content. Furthermore the observed quenching was greater than could be explained by a simple dilution of the cholestatrienol by the addition of cholesterol to the membrane. These data suggest an interaction between the sterol and the protein. The specificity of this interaction was explored by the addition of ergosterol, instead of cholesterol, to the disk membranes. Ergosterol was not able to inhibit the quenching of protein trytophans beyond that due to dilution of the cholestatrienol by addition of ergosterol to the membrane. The ability of cholesterol to compete with cholestatrienol for that interaction suggests a 'site' at which cholesterol contacts rhodopsin. The inability of ergosterol to compete with cholestatrienol for this 'site' suggested that the site was specific for the structure of cholesterol.