Bacteriology of endotracheal tube biofilms and antibiotic resistance: a systematic review

Bacteria commonly adhere to surfaces and produce polymeric material to encase the attached cells to form communities called biofilms. Within these biofilms, bacteria can appear to be many times more resistant to antibiotics or disinfectants. This systematic review explores the prevalence and microbial profile associated with biofilm production of bacteria isolated from endotracheal tubes and its associations with antimicrobial resistance. A comprehensive search was performed on databases PubMed, Embase, and Google Scholar for relevant articles published between 1st January 2000 and 31st December 2022. The relevant articles were exported to Mendeley Desktop 1.19.8 and screened by title and abstract, followed by full text screening based on the eligibility criteria of the study. Quality assessment of the studies was performed using the Newcastle-Ottawa Scale (NOS) customized for cross-sectional studies. Furthermore, the prevalence of antimicrobial resistance in biofilm-producers isolated from endotracheal tube specimens was investigated. Twenty studies encompassing 981 endotracheal tubes met the eligibility criteria. Pseudomonas spp. and Acinetobacter spp. were predominant isolates among the biofilm producers. These biofilms provided strong resistance against commonly used antibiotics. The highest resistance rate observed in Pseudomonas spp. was against fluoroquinolones whereas the least resistance was seen against piperacillin-tazobactam. A similar trend of susceptibility was observed in Acinetobacter spp. with a very high resistance rate against fluoroquinolones, third-generation cephalosporins and carbapenems. In conclusion, endotracheal tubes were associated with colonization by biofilm forming bacteria with varying levels of antimicrobial resistance. Biofilms may promote the occurrence of recalcitrant infections in endotracheal tubes which need to be managed with appropriate protocols and antimicrobial stewardship. Research focus should shift towards meticulous exploration of biofilm-associated infections to improve detection and management.

Avatrombopag for adult chronic primary immune thrombocytopenia: a randomized phase 3 trial in China

Background

Immune thrombocytopenia (ITP) is an autoimmune disorder with decreased platelet counts and increased bleeding risk.

Objectives

To evaluate the efficacy and safety of avatrombopag, a second-generation oral thrombopoietin receptor agonist, for the treatment of Chinese patients with chronic primary ITP.

Methods

This multicenter, randomized, double-blind, placebo-controlled phase 3 study (CTR20210431) consisted of a 6-week double-blind core treatment phase followed by a 20-week, open-label extension phase. Chinese adults with chronic primary ITP for at least 12 months and a platelet count <30 × 109/L were randomized (2:1) to receive avatrombopag (initial dose of 20 mg/day) or matched placebo. The primary endpoint was the proportion of subjects with a platelet count ≥50 × 109/L at week 6 of the core treatment phase in absence of rescue therapy.

Results

In total, 74 patients were randomized (avatrombopag: N = 48; placebo: N = 26) between March 5, 2021, and August 6, 2021; all of whom entered the extension phase (72 received avatrombopag up to 26 weeks). At week 6 of the core study, the platelet response (≥50 x 109/L) rate was significantly higher in the avatrombopag group (77.1%; 95% CI, 62.7, 88.0) vs placebo (7.7%; 95% CI, 1.0, 25.1); the treatment difference was 69.4% (95% CI, 56.2, 86.3; P < .0001). During the 6-week core study, treatment-emergent adverse events were reported in 41 (85.4%) and 20 (76.9%) patients in the avatrombopag and placebo groups, respectively. The most common avatrombopag-related treatment-emergent adverse events were upper respiratory tract infection (14/48 [29.2%]), increased platelet count (13/48 [27.1%]) and headache (7/48 [14.6%]).

Conclusion

Avatrombopag was efficacious and generally well tolerated in Chinese patients with chronic primary ITP, with comparable efficacy and safety to previous reports in Western patients.

Phase 1a study of the CDK4/6 inhibitor, FCN-437c, in Chinese patients with HR + /HER2- advanced breast cancer

Purpose This phase 1a, first-in-human study assessed the safety, maximum tolerated dose (MTD), pharmacokinetics (PK), and antitumor activity of FCN-437c, a cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor. Methods The study enrolled female patients with HR + /HER2- advanced breast cancer (BC) who failed standard of care therapy. A 3 + 3 dose-escalation design was utilized with a starting dose of 50 mg daily for 3 weeks on and 1 week off treatment in 28-day cycles. Patients received escalating doses of FCN-437c monotherapy (50, 100, 200, 300, and 450 mg). Results Seventeen patients received FCN-437c 50 mg (n = 3), 100 mg (n = 3), 200 mg (n = 3), 300 mg (n = 6), and 450 mg (n = 2). Two patients who received the 450-mg dose experienced dose-limiting toxicities (DLTs; grade 4 thrombocytopenia and neutropenia); no DLT was observed at any other dose level. Frequently reported treatment-emergent adverse events (TEAEs) of any grade were hematological: leukopenia (94.1%), neutropenia (88.2%), anemia (64.7%), and thrombocytopenia (47.1%). Grade 3-4 TEAEs included neutropenia (64.7%) and leukopenia (47.1%). Exposure of FCN-437c increased almost proportionally to doses ranging from 50 to 200 mg. At doses from 200 to 450 mg, there appeared to be a trend of saturation. The MTD was determined to be 300 mg. Of 15 patients with measurable disease, nine (60.0%) patients experienced stable disease; no complete or partial responses were observed. Conclusions These results established an acceptable safety profile for FCN-437c in patients with advanced BC, and there were no unexpected signals relative to other CDK4/6 inhibitors. (NCT04488107; July 13, 2020).

Abstract CT117: Phase I dose-escalation and dose-expansion trial of CDK4/6 inhibitor FCN-437c in Chinese female patients with ER+HER2- advanced breast cancer (ABC)

Background: CDK4/6 have been proved to play an essential role in cell proliferation and are often dysregulated particularly in HR-positive breast cancer. To date, three orally bioavailable CDK4/6 inhibitors, palbociclib, ribociclib and abemaciclib, have been approved for the treatment of ER+HER2- ABC in combination with AI/Fulvestrant or as monotherapy. FCN-437c is an oral, second generation CDK4/6 inhibitor, with antitumor activities of the combination with AI/Fulvestrant in in-vivo models with high potency, as well as good pharmacokinetic (PK) characteristics with brain penetration, and tolerable toxicities observed. Methods: This is a phase I, open label, first-in-human trial aiming to evaluate the safety, maximum tolerated dose (MTD), PK profile and anti-tumor activity of FCN-437c as monotherapy in patients with ABC failure to standard of care (phase 1a) and in combination with Letrozole in patients with 1L ABC (phase 1b). Here we report the phase 1a study result. Regular 3+3 dose escalation design was utilized with starting dose of 50 mg for 3 weeks on-1 week off in a 28-day cycle. 17 patients were enrolled from Feb.13th 2019 to Apr. 15th 2020 in different dose level: 50(n = 3), 100(n = 3), 200(n = 3), 300(n = 6) and 450(n = 2) mg. Results: As of the cut-off date on Aug. 10th 2020, a total of 17 patients participated in phase 1a. Sixteen patients (94.1%) and 13 patients (76.5%) had been treated with endocrine therapy and chemotherapy for ABC, respectively. Two patients in the 450 mg dose group experienced DLT of grade 4 thrombocytopenia and G4 neutropenia respectively, and no DLT was observed in other dose level. The most frequently reported was hematological TEAEs as of leukopenia (16/17 pts, 94.1%), neutropenia (15/17 pts, 88.2%), anemia (11/17 pts, 64.7%) and thrombocytopenia (8/17 pts, 47.1%). Major grade 3-4 TEAEs were neutropenia and leukopenia, occurred in 11 (64.7%) and 8 (47.1%) patients, respectively. The exposure (Cmax,AUC0-∞ ,AUC0-24,Cav-ss 24h) increased almost in proportion with dose following a multi-dose from 50 to 200mg. In multiple dose at 200 - 450 mg dose level, there appeared to be a trend of saturation. MTD of FCN-437c monotherapy was determined to be 300 mg and RP2D was 200 mg based on safety and PK data. Of 15 response evaluable patients, 9 (60.0%) had stable disease and no response was observed. PFS and OS were immature for report due to short follow-up duration.Conclusions: FCN-437c has established an acceptable safety profile and the toxicities were generally tolerable and manageable. A phase II trial of FCN-437c is now ongoing in combination with Letrozole or Fulvestrant in patients with ER+HER2- ABC, both in treatment naïve and relapse/refractory settings at 200 mg dose level.

Citation Format: Jian Zhang, Xiaojia Wang, Xian Wang, Aimin Hui, Zhuli Wu, Ling Tian, Changjiang Xu, Yuchen Yang, Wenjing Zhang, Xichun Hu. Phase I dose-escalation and dose-expansion trial of CDK4/6 inhibitor FCN-437c in Chinese female patients with ER+HER2- advanced breast cancer (ABC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT117.

Safety and immunogenicity of the SARS-CoV-2 BNT162b1 mRNA vaccine in younger and older Chinese adults: a randomized, placebo-controlled, double-blind phase 1 study

An effective vaccine is needed to end the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Here, we assess the preliminary safety, tolerability and immunogenicity data from an ongoing single-center (in Jiangsu province, China), parallel-group, double-blind phase 1 trial of the vaccine candidate BNT162b1 in 144 healthy SARS-CoV-2-naive Chinese participants. These participants are randomized 1:1:1 to receive prime and boost vaccinations of 10 µg or 30 µg BNT162b1 or placebo, given 21 d apart, with equal allocation of younger (aged 18-55 years) and older adults (aged 65-85 years) to each treatment group (ChiCTR2000034825). BNT162b1 encodes the SARS-CoV-2 spike glycoprotein receptor-binding domain (RBD) and is one of several messenger RNA-based vaccine candidates under clinical investigation. Local reactions and systemic events were generally dose dependent, transient and mild to moderate. Fever was the only grade 3 adverse event. BNT162b1 induced robust interferon-γ T cell responses to a peptide pool including the RBD in both younger and older Chinese adults, and geometric mean neutralizing titers reached 2.1-fold (for younger participants) and 1.3-fold (for the older participants) that of a panel of COVID-19 convalescent human sera obtained at least 14 d after positive SARS-CoV-2 polymerase chain reaction test. In summary, BNT162b1 has an acceptable safety profile and produces high levels of humoral and T cell responses in an Asian population.

Pharmacokinetics of Opicapone and Its Metabolites in Healthy White and Chinese Subjects

Opicapone (OPC) is a third-generation catechol-O-methyltransferase inhibitor developed to treat Parkinson disease and motor fluctuations. This open-label, single-center, phase 1 study aimed to evaluate the pharmacokinetics (PK) of OPC and its metabolites when administered as single and multiple doses in healthy White and Chinese subjects. The study enrolled a total of 30 White and Chinese healthy subjects, equally balanced among groups. The first dose of OPC was administered orally as a single dose of 50 mg on day 1, followed by a 10-day once-daily treatment from day 5 to day 14. Plasma concentrations of OPC and its metabolites were measured at 0 to 72 and 0 to 144 hours after dosing for single dose and multiple dose, respectively. Moreover, urine concentrations of OPC and its metabolite were measured 0 to 24 hours after dosing. PK parameters were derived from noncompartmental analysis. Geometric mean ratios and 90% confidence intervals for the main PK parameters were conducted to evaluate the ethnic difference between White and Chinese subjects. The plasma and urine exposure of OPC and its metabolites in Chinese subjects were similar to those in White subjects. These results indicated that ethnicity had no significant impact on PK of OPC between White and Chinese subjects.

Creating a community-based comprehensive intervention to improve asthma control in a low-income, low-resourced community

Introduction: Asthma evidence-based interventions (EBI) are implemented in the home, school, community or primary care setting. Although families are engaged in one setting, they often have to navigate challenges in another setting.Objective: Our objective is to design and implement a comprehensive plan which integrates EBI's and connects the four sectors in underserved communities such as Philadelphia.Methods: September 2015-April 2016 we implemented a three-pronged strategy to understand needs and resources of the community including 1) focus groups and key informant interviews, 2) secondary data analysis and 3) pilot testing for implementation to determine gaps in care, and opportunities to overcome those gaps.Results: Analysis of the focus group and key informant responses showed themes: diagnosis fear, clinician time, home and school asthma trigger exposures, school personnel training and communication gaps across all four sectors. EBI's were evaluated and selected to address identified themes. Pilot testing of a community health worker (CHW) intervention to connect home, primary care and school resulted in an efficient transfer of asthma medications and medication administration forms to the school nurse office for students with uncontrolled asthma addressing a common delay leading to poor asthma management in school.Conclusion: Thus far there has been limited success in reducing asthma disparities for low-income minority children. This study offers hope that strategically positioning CHWs may work synergistically to close gaps in care and result in improved asthma control and reduced asthma disparities.

Tunable phonon-cavity coupling in graphene membranes

A major achievement of the past decade has been the realization of macroscopic quantum systems by exploiting the interactions between optical cavities and mechanical resonators. In these systems, phonons are coherently annihilated or created in exchange for photons. Similar phenomena have recently been observed through phonon-cavity coupling-energy exchange between the modes of a single system mediated by intrinsic material nonlinearity. This has so far been demonstrated primarily for bulk crystalline, high-quality-factor (Q > 10(5)) mechanical systems operated at cryogenic temperatures. Here, we propose graphene as an ideal candidate for the study of such nonlinear mechanics. The large elastic modulus of this material and capability for spatial symmetry breaking via electrostatic forces is expected to generate a wealth of nonlinear phenomena, including tunable intermodal coupling. We have fabricated circular graphene membranes and report strong phonon-cavity effects at room temperature, despite the modest Q factor (∼100) of this system. We observe both amplification into parametric instability (mechanical lasing) and the cooling of Brownian motion in the fundamental mode through excitation of cavity sidebands. Furthermore, we characterize the quenching of these parametric effects at large vibrational amplitudes, offering a window on the all-mechanical analogue of cavity optomechanics, where the observation of such effects has proven elusive.

Social prescribing through arts on prescription in a U.K. city: participants' perspectives (part 1)

OBJECTIVES

In the U.K., the era of New Labour witnessed a developing connection between the arts (and sport) and 'neighbourhood renewal'. The concept of the usefulness of the arts to health has gained credence largely through community-based arts. Whilst there is an increasing evidence base for the usefulness of community arts delivery, there is little published evidence in the peer-reviewed literature of the effectiveness of delivery of Arts on Prescription. The aim of this study was therefore to explore the experiences of people who have engaged with Arts on Prescription programme of work.

STUDY DESIGN

This qualitative research study used a narrative inquiry approach amongst participants of Arts on Prescription programme of work.

METHODS

Sixteen in-depth interviews were conducted in community-based arts venues. Each participant was using or had used mental health services.

RESULTS

Participants experienced Arts on Prescription as a creative and therapeutic environment. It was considered a safe place where participants can be creative with others who have shared similar experiences. Participants experienced social, psychological and occupational benefits, although these benefits are not easily separated as they are intermingled. By feeling accepted and amongst people who have had similar experiences, participants also gained a sense of social belonging. A number of participants also found new opportunities for the future.

CONCLUSIONS

Community-based arts groups that are professionally facilitated may provide a therapeutic environment for participants. Participants gained a sense of pride in their work, and experienced psychological, social and occupational benefits.

Arts In-Reach: taking 'bricks off shoulders' in adult mental health inpatient care

This article reports upon a research study focusing on a programme of work called Arts In-Reach. The programme was designed to provide a participatory arts programme for the adult mental health inpatient wards in a city in the UK. The aim of the research study was to explore the experiences of people who have engaged with the Arts In-Reach programme of work. Eleven qualitative interviews were conducted among participants of the programme. Consistent with other research, this study reveals how people on the wards often feel powerless and bored. The feelings of boredom are exacerbated as people recover. Participating in the arts groups has alleviated some of those feelings. Furthermore, participation has also increased people's social interactions and given opportunity for self-expression. The arts activities also provide a distraction for people and some appreciated being able to talk about matters other than their 'illness'. The arts activities helped people to think about their future and how they might take their artwork forward. For some people, thinking about the future helped with restoring a sense of hope, a quality imperative for recovery.

Social prescribing through arts on prescription in a U.K. city: referrers' perspectives (part 2)

OBJECTIVES

This study provides some insight into the perceived benefits of an Arts on Prescription service in the U.K. according to referrers. Social prescribing provides a framework for emerging alternative approaches to mental distress. The aim of this study was to investigate the views of referrers to an Arts on Prescription programme regarding the quality and effectiveness of the service.

STUDY DESIGN

For this study, 10 individuals were recruited from a potential total of 148 referrers who had referred their clients to Arts on Prescription between 2008 and 2011.

METHOD

Qualitative, in-depth semi-structured interviews were conducted and the findings were thematically analysed.

RESULTS

It was evident that referrers value Arts on Prescription. It is considered to be a therapeutic, relaxing and safe environment that is professionally led. Referrers reported that their clients take pride in the work they have created at Arts on Prescription. They believe that the programme helps their clients to build confidence, find meaningful occupation, develop skills and express themselves. The social opportunities provided by the programme are considered significant, as well as the peer support that is evident.

CONCLUSIONS

Social prescribing enables general practitioners to have greater options when helping patients with complex social problems. As such, the programme is clearly valued by referrers for their clients. The programme offers valuable social benefits that are becoming reduced in an era of closure of day service provision. There is concern regarding whether such valuable resources will be commissioned in the future.

Experiences and constructions of art: a narrative-discourse analysis

A narrative-discourse analysis was conducted to study the narratives of mental health service users talking about their engagement with art. The sample was drawn from a group of people who had attended arts workshops organized by a mental health service provider. Eleven people were interviewed and were asked to tell the story of their involvement in art and its significance to their lives. The data were analysed using a discourse analysis approach. Art is constructed as therapeutic within an illness repertoire. Emotions are inseparable from creative expression and identity claims are made in relation to being an artist.

A phase I/II trial of celecoxib with chemotherapy and radiotherapy in the treatment of patients with locally advanced oesophageal cancer

BACKGROUND

The study's aim was to determine the maximum tolerated dose (MTD) of celecoxib combined with chemoradiotherapy (CRT) for locally advanced oesophageal cancer (OC).

METHODS

CRT comprised of 5FU (1000 mg/m(2)/day, days 1-4, weeks 1 & 5), cisplatin (75 mg/m(2), days 1 & 29) and radiotherapy (50 Gy in 25 fractions or 50.4 Gy in 28 fractions). Celecoxib was given daily during CRT at one of five doses (200 mg bd to 600 mg bd). Three to six patients were assigned per dose.

RESULTS

Thirteen patients were recruited before trial closure due to external safety concerns regarding celecoxib. Median follow up was 17 months (95% CI 9 - >39). The highest administered dose was 400 mg bd (n=4) with one dose-limiting toxicity at this level: grade 3 rash. Five (38%) and 8(62%) patients had grade 3 non-haematological and haematological toxicities respectively. No grade 4 toxicities occurred. Radiological response rate was 54% (n=7: all CR). Six patients had resection with one pathological CR. Median progression-free and overall survival were 8.8 (95% CI 5.1 - >24.8) and 19.6 months (95% CI 7.3 - >39) respectively.

CONCLUSIONS

A MTD was not reached. The regimen was tolerable, indicating that celecoxib can be safely administered with CRT for locally advanced OC.

High-performance liquid chromatographic determination of polysorbate 80 in pharmaceutical suspensions

A quick HPLC method is reported for the analysis of polysorbate 80 in pharmaceutical suspensions. A typical pharmaceutical suspension was mixed with dilute potassium hydroxide, and heated at 40 degrees C for 6 h. This procedure resulted in quantitative hydrolysis of polysorbate 80 to release oleic acid. A quick HPLC procedure was used to analyze the hydrolyzed samples without further sample treatment. Polysorbate 80 USP, treated in the same way as the pharmaceutical suspensions, was used as standard. Full validation tests were carried out and the validation studies demonstrated that this method is suitable for accurate and reproducible analysis of polysorbate 80 in pharmaceutical suspensions.

Cytologic evaluation of surgical irrigation fluid following resection of head and neck squamous cell carcinoma

INTRODUCTION

Historically, squamous cells exfoliated from head and neck carcinoma resection have been implicated in locoregional recurrence, but there have been few studies demonstrating the presence of these cells. This study was designed to evaluate the presence of exfoliated malignant cells in surgical irrigation fluid collected during head and neck cancer resection.

METHODS

Thirty patients undergoing surgery for biopsy-proven squamous cell carcinoma had their surgical sites irrigated with 1,000 cc of normal saline. Surgical gloves and instruments were also washed. These samples were prepared and stained using standard squamous cell cytologic stains. All cases were reviewed by one cytopathologist.

RESULTS

Eighteen patients (60%) had positive or suspicious cytology detected in at least one of the surgical samples. In patients with T0 and T1 tumours, all surgical samples were negative. Positive or suspicious cytology was detected in the primary site and glove and instrument irrigation in 40% of patients with T2 tumours, 42% of patients with T3 tumours, and 50% of patients with T4 tumours. This was statistically significant (p < .05). Positive or suspicious cytology was detected in the neck and glove and instrument irrigation in 29% of patients with an N0 neck, 31% of patients with an N1 neck, 39% of patients with an N2 neck, and 100% of patients with an N3 neck. Five of seven patients (71%) with previous radiation therapy had positive or suspicious cytology in at least one of the surgical samples.

CONCLUSIONS

Higher tumour and nodal staging and a previous history of radiation therapy are associated with an increased incidence of positive or suspicious cytology in surgical irrigation fluid. These findings have implications for surgical protocols.

A radiological technique for the assessment of wear in prosthetic knee replacements

OBJECTIVE

Wear of the polyethylene insert is a well-recognised cause of implant failure in total knee replacements. The purpose of this study was to evaluate a simple, digital fluoroscopic technique for the assessment of wear in knee prostheses.

DESIGN

Fluoroscopic images of knee prostheses were produced both of a phantom and in a patient group. Joint space thickness was measured by reference to a known diameter. Measurements were made to assess repeatability of positioning, inter-and intra-observer variance and the effect of angulation.

RESULTS

Standard phantom images showed small variation between measurements, high inter-reader correlation (Pearson's correlation coefficient, r=0.98, P<0.001; coefficient of variation=0.53%) and low intra-reader variation (coefficient of variation=0.57%). Inter- and intra-imager variation were low (coefficient of variation=1.05% and 0.88%, respectively). In the patient group, the range of joint space measurements was 1.9-8.9 mm. The coefficient of variation in insert measurements on repeated images was 2.0%. Repeatability of measurements was 0.2 mm with 99% confidence interval.

CONCLUSIONS

This technique allows repeatable, precise measurement of insert thickness. The technique may be adapted to any implant where a reliable calibrating distance is present.

Characterization of a new human B7-related protein: B7RP-1 is the ligand to the co-stimulatory protein ICOS

Optimal T cell activation requires the interactions of co-stimulatory molecules, such as those in the CD28 and B7 protein families. Recently, we described the co-stimulatory properties of the murine ligand to ICOS, which we designated as B7RP-1. Here, we report the co-stimulation of human T cells through the human B7RP-1 and ICOS interaction. This ligand-receptor pair interacts with a K:(D) approximately 33 nM and an off-rate with a t((1/2)) > 10 min. Interestingly, tumor necrosis factor (TNF)-alpha differentially regulates the expression of human B7RP-1 on B cells, monocytes and dendritic cells (DC). TNF-alpha enhances B7RP-1 expression on B cells and monocytes, while it inhibits it on DC. The human B7RP-1-Fc protein or cells that express membrane-bound B7RP-1 co-stimulate T cell proliferation in vitro. Specific cytokines, such as IFN-gamma and IL-10, are induced by B7RP-1 co-stimulation. Although IL-2 levels are not significantly increased, B7RP-1 co-stimulation is dependent on IL-2. These experiments define the human ortholog to murine B7RP-1 and characterize its interaction with human ICOS.

Clinical findings, imaging characteristics and outcome in catastrophic post-encephalitic epilepsy

OBJECTIVES

The aim of this study is to characterize the clinical features and prognostic factors for intractable, post-encephalitic epilepsy.

METHODS

We studied retrospectively 42 patients (26 men) evaluated between 1982 and 1999. MRI, neuropsychological findings, interictal and ictal scalp EEG were reviewed for all patients. Fifteen patients had additional stereo EEG (SEEG) studies.

RESULTS

The mean age at encephalitis was 17 years (SD = 15.5); etiology was identified in 18 patients. During the acute illness, 79% had status epilepticus (SE) or recurrent seizures and 76% were in coma; mean Glasgow outcome scale (GOS) was 3.6 (SD = 0.8). The mean latency to seizure onset was 0.8 years (SD = 1.9). The majority (72%) presented with complex partial seizures with or without secondary generalization. According to interictal epileptiform findings and the predominant seizure onset pattern as found on scalp EEG, patients were unilateral temporal (UTLE) = 8, bilateral temporal (BTLE) = 12, and extratemporal/multifocal or generalized (ETMFE) = 22 patients. MRI atrophy and/or signal changes were unilateral temporal in 7 (18%), bilateral temporal in 5 (13%), multilobar/diffuse in 20 (51%), and absent in 7 (18%). ANOVA revealed significant differences in mean GOS between UTLE versus BTLE and ETMFE (4.7 versus 3.2 versus 3.6; p < 0.0001), but not in age at encephalitis. Latency to the first unprovoked seizure was shorter in patients with ETMFE compared to UTLE and BTLE (p < 0.01). Surgery was performed in 24 patients. The best outcome was obtained in UTLE (7/8 class I and II). In the others, outcome was poor in the majority (13/16 class III and IV).

CONCLUSION

There is a small subgroup of patients with postencephalitic UTLE for whom the outcome is favorable. The majority of our patients had multifocal seizure onset with BTLE and ETMFE, and poor outcome after surgical treatment.

Successful epilepsy surgery in catastrophic postencephalitic epilepsy

The authors studied prognostic factors for surgical treatment in 22 patients with intractable postencephalitic epilepsy. A small subgroup of patients (9/22) had a positive outcome after resective surgery. They had a higher functional level after encephalitis as measured by Glasgow Outcome Score, a longer time interval between encephalitis and onset of seizures, and localization of ictal EEG to one temporal lobe. The other patients had devastating seizures with poor outcome after surgery.

Altered p21(WAF1/CIP1) expression is associated with poor prognosis in extrahepatic bile duct carcinoma

This study was designed to determine the clinical implications of p21(WAF1/CIP1) expression and the relationship between p21(WAF1/CIP1) expression and p53 status in extrahepatic bile duct carcinoma (EBDC). Low p21(WAF1/CIP1) expression was immunohistochemically detected in 23 (67.6%) of 34 EBDCs, moderate in six (17.7%), and high in five (14.7%). Kaplan-Meier curves showed that low and high p21(WAF1/CIP1) expressions were significantly associated with shortened disease-free survival (low vs. moderate, P=0.02; high vs. moderate, P=0.01). There was no correlation between p21(WAF1/CIP1) and p53 expression. These findings suggest that altered p21(WAF1/CIP1) expression exerts an adverse influence on the prognosis of EBDC.

T-cell co-stimulation through B7RP-1 and ICOS

T-cell activation requires co-stimulation through receptors such as CD28 and antigen-specific signalling through the T-cell antigen receptor. Here we describe a new murine costimulatory receptor-ligand pair. The receptor, which is related to CD28 and is the homologue of the human protein ICOS, is expressed on activated T cells and resting memory T cells. The ligand, which has homology to B7 molecules and is called B7-related protein-1 (B7RP-1), is expressed on B cells and macrophages. ICOS and B7RP-I do not interact with proteins in the CD28-B7 pathway, and B7RP-1 co-stimulates T cells in vitro independently of CD28. Transgenic mice expressing a B7RP-1-Fc fusion protein show lymphoid hyperplasia in the spleen, lymph nodes and Peyer's patches. Presensitized mice treated with B7RP-1-Fc during antigen challenge show enhanced hypersensitivity. Therefore, B7RP-1 exhibits co-stimulatory activities in vitro and in vivo. ICOS and B7RP-1 define a new and distinct receptor-ligand pair that is structurally related to CD28-B7 and is involved in the adaptive immune response.

Folding and purification of a recombinantly expressed interferon regulatory factor, IRF-4

Interferon regulatory factor 4 (IRF-4), an intracellular, multidomain protein, is a member of the interferon regulatory factor family and a lymphoid-specific transcription factor that can form a ternary complex with DNA and the transcription factor PU.1. Recombinant human IRF-4 was expressed in Escherichia coli and purified from the soluble cell extract and the insoluble inclusion bodies. The inclusion bodies were solubilized with guanidinium-hydrochloride and sequentially buffer exchanged into urea- and then NaCl-containing solutions. This two-step process for the removal of the denaturants was the critical step to allow for the correct folding of IRF-4. Following purification through immobilized metal affinity, hydrophobic interaction, and gel permeation chromatographies, the renatured protein was shown to be structurally and physically equivalent to a sample of IRF-4 produced in the soluble fraction of E. coli cells. This was confirmed by near and far UV circular dichroism analysis, including thermal stability analysis. The purified IRF-4 was also shown to be capable of binding DNA in a PU.1-dependent manner by electrophoretic mobility shift analysis. The protein folding and purification methods are suitable for producing large quantities of full-length IRF-4.

Clinical audit of a new radiation oncology department in the first 20 months of establishment

This audit was carried out to examine the workload statistics of the Radiation Oncology Department at Liverpool Hospital in its first 20 months of operation, and their implications for the delivery of radiation oncology services in the Southwestern Sydney Area Health Service (SWSAHS). Data on patient demographics, primary diagnosis and radiotherapy treatment details from April 1995 to December 1996 were analysed. In this time period, 1329 new patients were seen; 90.6% of them lived in the local area health service and approximately 30% came from a non-English-speaking background. The most common primary tumour sites were breast (25%), prostate (17%) and lung (15%). Nine hundred and ninety-eight of the new patients (74%) proceeded to have radiotherapy. Fifty-seven per cent were treated radically with curative or adjuvant intent, the remainder were treated palliatively for symptom control or local control. The most commonly used fractionation schedules were 31-35 fractions for radical treatment and 1-5 fractions for palliative treatment. Forty patients (4%) did not complete the treatment course as planned. Eighty-nine patients (9%) were retreated in the same time period. These workload statistics were helpful in determining ongoing workload and planning future expansion.

Inhibition of activator protein 1 activity by paclitaxel suppresses interleukin-1-induced collagenase and stromelysin expression by bovine chondrocytes

OBJECTIVE

Cytokine-induced collagenase 1 (matrix metalloproteinase 1 [MMP-1]) and stromelysin 1 (MMP-3) expression is dependent on activator protein 1 (AP-1) activation and have a fundamental role in the pathophysiology of arthritic diseases by degrading connective tissues. This study evaluates the effect of paclitaxel on AP-1 activation and examines its effect on the expression of 2 major matrix metalloproteinases, MMP-1 and MMP-3, and its effect on AP-1 activation.

METHODS

MMP-1, MMP-3, c-fos, and c-jun messenger RNA (mRNA) levels were measured in interleukin-1 (IL-1)-induced primary chondrocytes in the presence and absence of paclitaxel. The effect of paclitaxel on AP-1 promoter activity was studied by chloramphenicol acetyltransferase assays in IL-1-stimulated chondrocytes. The same conditions were applied to studies of the effect of paclitaxel on binding at the AP-1 site by gel-shift mobility assays. The cytotoxicity effect of paclitaxel on chondrocytes was studied by examining cell viability and expression of the matrix molecules aggrecan and type II collagen.

RESULTS

IL-1-induced MMP-1 and MMP-3 mRNA levels were markedly reduced in paclitaxel-treated chondrocytes. Further, IL-1-induced AP-1 activation and AP-1 binding were inhibited by paclitaxel. However, there was no effect on the expression of c-fos or c-jun mRNA levels. Chondrocyte viability was not affected by paclitaxel, and there was no effect on the expression of housekeeping genes or the major cartilage matrix molecules aggrecan and type II collagen.

CONCLUSION

These studies demonstrate that paclitaxel is a potent inhibitor of MMP-1 and MMP-3 synthesis through the AP-1 site. However, inhibition of AP-1 activity by paclitaxel does not affect the viability of chondrocytes or the expression of matrix molecules.

Trace Element Concentrations in Two Subpopulations of Lesser Snow Geese from Wrangel Island, Russia

Lesser snow geese (Anser c. caerulescens) from the Wrangel Island, Russia breeding colony spend the winter in two widely separated areas: the northern subpopulation in southern British Columbia and northern Washington and the southern subpopulation in the Central Valley of California. We examined 19 trace elements in the eggs and livers of geese from these two subpopulations to examine whether geese from the different wintering areas have similar trace element burdens. Eggs collected at the breeding colony from geese of the southern subpopulation had slightly higher levels of manganese, an element that can cause neurological damage and behavioral changes in chicks, than geese of the northern subpopulation. Livers from adult geese collected on the two wintering areas showed significant differences in trace elements including copper, iron, magnesium, molybdenum, and zinc. Copper concentrations in the livers of geese from the southern subpopulation were much higher than those from the northern subpopulation (&xmacr; = 116 vs. 46 ppm; dry weight). Elevated levels of copper may induce anemia in birds. The differences in trace element concentrations of these two subpopulations may be related to farming practices in their wintering areas. Geese from the northern subpopulation feed in pastures and coastal marshes and migrate along the coast, but geese from the southern subpopulation feed predominantly in rice fields and migrate over farm land. Copper and manganese are major components of fertilizers and fungicides commonly applied during rice cultivation.

DNA hypermethylation at the D17S5 locus is associated with gastric carcinogenesis

The aim of this study was to elucidate the significance of aberrant DNA methylation in gastric carcinogenesis. The DNA methylation status at the D17S5 locus, at which a candidate tumor suppressor gene, HIC-1, was identified, of gastric cancers and non-cancerous gastric mucosae from 42 gastric cancer patients was examined by Southern blotting using a methylation-sensitive restriction enzyme. DNA hypermethylation was observed in 15, 13, 25 and 45% of the tissues showing no remarkable histological findings, chronic gastritis without intestinal metaplasia, intestinal metaplasia and gastric cancer, respectively. The incidence of DNA hypermethylation was significantly higher in gastric cancers than in non-cancerous gastric mucosae (P < 0.05). DNA hypermethylation was often accompanied by allelic loss at the same locus in gastric cancers. DNA hypermethylation at the D17S5 locus, which was even detected in precancerous conditions, including intestinal metaplasia, may play a role in gastric carcinogenesis.

Paclitaxel selectively induces mitotic arrest and apoptosis in proliferating bovine synoviocytes

OBJECTIVE

Rheumatoid arthritis (RA) is characterized by chronic progressive destruction of joints involving several disease processes, such as villous hypertrophy, proliferation of synovial lining cells, and infiltration of inflammatory cells. Synovial cell activation and proliferation is thought to be a key step in the destruction of cartilaginous and bony tissues in RA joints. In view of the invasive properties of synoviocytes in RA, we conducted in vitro studies to determine the mechanism of action of paclitaxel (Taxol) on synoviocytes, which may account for the inhibition of joint destruction found when this agent is administered.

METHODS

Cultured synovial cells were treated with various concentrations of paclitaxel and were evaluated by cell viability, fluorescence microscopy, flow cytometry of DAPI-stained cells, and electron microscopy.

RESULTS

The data indicated that paclitaxel inhibited synoviocyte proliferation by a G2/M phase block and was toxic to synoviocytes by inducing apoptosis. Confluent cells such as chondroyctes and synoviocytes were not affected by paclitaxel. Synchronization of synovioyctes at the G1/S boundary effectively abolished paclitaxel-induced apoptosis.

CONCLUSION

The data indicate that induction of apoptosis in synoviocytes might be dependent on transit through the cell cycle, specifically through G2 and mitosis. Further, paclitaxel was selectively toxic to proliferating synoviocytes but spared nonproliferating synoviocytes and chondrocytes. These results demonstrate that paclitaxel can inhibit synovial cell proliferation and pannus formation in RA joints in vivo. We suggest that paclitaxel be considered as a prototypical compound for a new class of potential chondroprotective agents.

Intact lung cytochrome P-450 is not required for hypoxic pulmonary vasoconstriction

Lung cytochrome P-450 has been suggested to play a role in hypoxic pulmonary vasoconstriction. We reexamined this hypothesis using specific suicide substrate inhibitors of cytochrome P-450, 1-aminobenzotriazole (1-ABT), and chloramphenicol. In isolated, blood-perfused rat lungs, 1-ABT (0.5 mg/ml) and chloramphenicol (1 mg/ml) inhibited lung microsomal cytochrome P-450 (ethoxycoumarin O-deethylase) activity to 24 and 44% of control, respectively, and blunted hypoxia and angiotensin II-induced vasoconstriction. The depression of vascular contraction by 1-ABT was not due to an effect on calcium channels, since similar concentrations of 1-ABT had no inhibitory activity on electrical field-stimulated contractile response in rabbit papillary muscle strips. However, when 1-ABT was washed out of the lung after preincubation, the vascular reactivity to hypoxia and angiotensin II was restored despite persistent depression of lung cytochrome P-450 activity to 26% of control values. In isolated rat aortic and pulmonary arterial rings, addition of 1-ABT or metyrapone to the organ bath acutely reversed norepinephrine-induced contraction but preincubation with 1-ABT, metyrapone, or chloramphenicol had no effect on subsequent norepinephrine contractions. We conclude that 1-ABT inhibited lung vascular reactivity by a mechanism independent of cytochrome P-450 inhibition or calcium channel blockade and that an intact lung cytochrome P-450 system is not required for hypoxic pulmonary vasoconstriction in rat lungs.

Molecular cloning of multiple subtypes of a novel rat brain isoform of the alpha 1 subunit of the voltage-dependent calcium channel

Several cDNAs encoding an isoform of the alpha 1 subunit of the voltage-dependent calcium channel were isolated from rat brain cDNA libraries. The complete nucleotide sequence of 6975 bp encodes a protein of 1634 amino acids, which corresponds to an Mr of 186,968. The protein exhibits 71% and 76% homology to skeletal and cardiac alpha 1 subunits, respectively. When compared with skeletal and cardiac alpha 1 isoforms, the rat brain protein is intermediate in size at the amino terminus and shorter at the carboxyl terminus. Multiple subtypes of this alpha 1 isoform cDNA were characterized. These are indicative of alternative splicing of a primary transcript and encode three variants between motif I and motif II and two within the S3 region of motif IV. Thus, multiple isoforms of this rat brain alpha 1 subunit are possible.