Renal Denervation: A Practical Guide for Health Professionals Managing Hypertension

Growing evidence demonstrates the suitability of renal denervation in a broad population of patients; however, questions remain over its suitability and practical implementation. Given the rapidity of emerging data, this has been a challenging field for potential adopters to navigate. The purpose of this article is twofold: to provide navigation through emerging clinical data and evolving guidance; and to provide physicians with practical, evidence-based advice for identifying eligible patients and providing appropriate management in the pre- and postintervention settings. Although many of these recommendations are based on existing published guidance documents, we reflect equally on our own experiences of using this technology.

The expendables: Bioarchaeological evidence for pauper apprentices in 19th century England and the health consequences of child labour

Child labour is the most common form of child abuse in the world today, with almost half of child workers employed in hazardous industries. The large-scale employment of children during the rapid industrialisation of the late 18th and early 19th centuries in England is well documented. During this period, the removal of pauper children from workhouses in cities to work as apprentices in rural mills in the North of England was commonplace. Whilst the experiences of some of these children have been recorded historically, this study provides the first direct evidence of their lives through bioarchaeological analysis. The excavation of a rural churchyard cemetery in the village of Fewston, North Yorkshire, yielded the skeletal remains of 154 individuals, including an unusually large proportion of children aged between 8 to 20 years. A multi-method approach was undertaken, including osteological and palaeopathological examination, stable isotope and amelogenin peptide analysis. The bioarchaeological results were integrated with historical data regarding a local textile mill in operation during the 18th-19th centuries. The results for the children were compared to those obtained from contemporaneous individuals of known identity (from coffin plates) of comparable date. Most of the children exhibited distinctive 'non-local' isotope signatures and a diet low in animal protein when compared to the named local individuals. These children also showed severe growth delays and pathological lesions indicative of early life adversity, as well as respiratory disease, which is a known occupational hazard of mill work. This study has provided unique insights into the harrowing lives of these children; born into poverty and forced to work long hours in dangerous conditions. This analysis provides a stark testimony of the impacts of industrial labour on the health, growth and mortality risk of children, with implications for the present as well as our understanding of the past.

Gastroschisis ultrasound bowel characteristics demonstrate minimal impact on perinatal outcomes

BACKGROUND

Bowel dilation and bowel wall thickness are common prenatal ultrasound measurements for fetuses with gastroschisis. Data regarding antenatal sonographic bowel findings and postnatal outcomes are conflicting. Our objective was to evaluate the impact of in utero bowel measurements on perinatal outcomes in gastroschisis pregnancies.

METHODS

Retrospective cohort study of 116 pregnancies complicated by gastroschisis between 2011 and 2020. We reviewed ultrasounds documenting fetal bowel measurements. To evaluate the association of these measurements with antepartum and delivery outcomes, we ran logistic and linear models using generalized estimating equations.

RESULTS

Eleven perinatal outcomes reached statistical significance, although with minimal clinical impact given small magnitude of effect. Intra-abdominal bowel dilation was associated with a 0.5 week decrease in delivery gestational age (GA) (95% CI -0.07, -0.03) and a 6.93 g increase in birth weight (95% CI 1.54, 28.73). Intra-abdominal bowel wall thickness was associated with later GA of non-stress test (NST) start of 0.22 weeks (95% CI 0.07, 0.37), increased delivery GA of 0.08 weeks (95% CI 0.02, 0.15), 0.006 decrease in umbilical artery (UA) pH (95% CI -0.009, -0.003), 0.26 increase in UA base deficit (95% CI 0.09, 0.43), and decreased odds of cesarean delivery (OR = 0.83, 95% CI 0.70, 0.99). Extra-abdominal bowel wall thickness was associated with a 0.1 increase in UA base deficit (95% CI 0.02, 0.19) and a 0.05 increase in 5-min APGAR score (95% CI 0.01, 0.09). Stomach cross-section was associated with a 0.01 week decrease in delivery GA (95% CI -0.02, -0.001) and increased odds of receiving betamethasone (OR = 1.02, 95% CI 1.01, 1.04).

CONCLUSIONS

In utero bowel characteristics reached statistical significance for several outcomes, but with minimal meaningful clinical differences in outcomes.

146 GOLD STANDARD GOAL-SETTING: ARE WE HITTING THE MARK? IMPLEMENTING AN INTERDISCIPLINARY GOAL-SETTING PATHWAY IN STROKE REHABILITATION

Background

The cornerstone of rehabilitation is effective and realistic interdisciplinary goal-setting with patient and family engagement across the continuum of recovery. The Royal College of Physicians National Clinical Guidelines for Stroke (2016) highlights the importance of encouraging self-management and self-efficacy to support a more person-orientated approach. This quality improvement initiative aimed to introduce a structured interdisciplinary goal-setting pathway on a post-acute 14-bed stroke unit.

Methods

An interdisciplinary working group was established comprising of Physiotherapy, Occupational Therapy, Speech & Language Therapy, Medical Social Work and Nursing. Quality improvement methodology was used to sequentially implement change over a 6-month period. The restructure included the introduction of an initial and review goal-focused family meeting. An interdisciplinary tool was developed based on the East Kent Outcome System (EKOS). A series of workshops was delivered to support implementation.

Results

An interdisciplinary goal-setting pathway is currently being piloted for 6 months on the stroke unit. To date, 22 staff have been trained and 9 patients have progressed through the updated pathway. Analysis has provided useful clinical insights and qualitative feedback has been collated regarding the benefits of the early opportunity to meet the team, establishing patient’s personal goal priorities and clear timeframes.Furthermore, repeat trials followed by reflections have enabled the team to develop consistency and confidence in person-centred, interdisciplinary goal-setting. It is acknowledged that this initiative has been a significant change process for the team and that adjustments are being made, in line with the principles of quality improvement.

Conclusion

This person-orientated interdisciplinary process is evidence-based and in line with national standards and guidelines for stroke rehabilitation. Formal training in EKOS is planned and a clinical audit will follow the pilot phase to systematically evaluate the change in practice.

Waitlisted and Transplant Patient Perspectives on Expanding Access to Deceased-Donor Kidney Transplant: A Qualitative Study

Background:

A concerning number of kidneys (eg, expanded donor criteria, extended criteria, or marginal kidneys) are discarded yearly while patients experience significant morbidity and mortality on the transplant waitlist. Novel solutions are needed to solve the shortage of kidneys available for transplant. Patient perceptions regarding the use of these less than ideal kidneys remain unexplored.

Objective:

To explore the perspectives of patients who have previously received a less than ideal kidney in the past and patients awaiting transplant who could potentially benefit from one.

Design:

Qualitative description study.

Setting:

2 provinces in Canada participated (Saskatchewan and Manitoba).

Patients:

Patients with end-stage kidney disease who were awaiting kidney transplant and were either (a) aged 65 years and older, or (b) 55 years and older with other medical conditions (eg, diabetes).

Methods:

Criterion sampling was used to identify participants. Semi-structured, one-on-one interviews were conducted virtually, which explored perceived quality of life, perceptions of less than ideal kidneys, risk tolerance for accepting one, and educational needs to make such a choice. The interviews were transcribed verbatim and thematic analysis was used to analyze the data.

Results:

15 interviews were conducted with usable data (n = 10 pretransplant; n = 5 posttransplant). Participants were a mean of 65.5 ± 8.8 years old. Four interrelated themes became prominent including (1) patient awareness and understanding of their situation or context, (2) a desire for information, (3) a desire for freedom from dialysis, and (4) trust. Subthemes of transparency, clarity, standardization, and autonomy were deemed important for participant education. The majority of pretransplant participants (n = 8/10) indicated that between 3 and 5 years off of dialysis would make the risk of accepting a less than ideal kidney feel worthwhile.

Limitation:

The study setting was limited to 2 Canadian provinces, which limits the generalizability. Furthermore, the participants were homogenous in demographics such as ethnicity.

Conclusion:

These findings indicate that patients are comfortable to accept a less than ideal kidney for transplant in situations where their autonomy is respected, they are provided clear, standardized, and transparent information, and when they trust their physician. These results will be used to inform the development of a new national registry for expanding access to deceased-donor kidney transplant.

Trial Registration:

Not registered.

219 IMPROVING DELIRIUM SCREENING AND MANAGEMENT IN POST-ACUTE REHABILITATION: A MULTI-STAGE QUALITY IMPROVEMENT INITIATIVE

Background

There is risk of delirium among older patients on transition from acute care to post-acute rehabilitation (Marcantonio et al. 2003). The 4AT is the recommended delirium detection tool for clinical practice (Tieges et al. 2020). A multi-disciplinary led quality improvement project was undertaken to standardise and improve delirium screening and management in the older person’s rehabilitation service of a post-acute rehabilitation hospital.

Methods

A retrospective audit of medical charts was completed for all patients admitted to a post-acute older person’s rehabilitation service from October 2019 to December 2019. Following that audit, there was a staff education intervention focusing on delirium awareness, screening and management. Furthermore, a dedicated ‘Delirium Champions Group’ was formed with representatives from the multi-disciplinary team. A Delirium Screen pro-forma was developed and implemented by this group. It included an attached 4AT sticker for all new admission medical charts. A post intervention medical chart audit was completed for all admissions to the same ward from October to December 2020.

Results

The pre-intervention chart audit showed 0% compliance with any form of formal delirium screening tool. The majority of patients had at least 2 delirium risk factors at the time of admission. The post-intervention audit recorded 92% compliance with 4AT use at the time of admission as well as full completion of the Delirium Screen pro-forma which included the documentation of risk factors for delirium. The Delirium Champions Group provide ongoing staff education, resources and are now exploring hospital environmental design and its role in delirium prevention.

Conclusion

This initiative lead to a significant improvement in the completion of delirium screening in post-acute rehabilitation. This project had the secondary benefit of prompting the formation of a dedicated delirium improvement group focusing on delirium awareness, screening, documentation, management and ultimately prevention.

Canadian Society of Transplantation White Paper: Ethical and Legal Considerations for Alcohol and Cannabis Use in Solid Organ Listing and Allocation

Alcohol and cannabis use as a contraindication to organ transplantation is a controversial issue. Until recently, patients in Canada with alcohol-associated liver disease were required to demonstrate abstinence for 6 mo to receive a liver transplant. There is no equivalent rule that is applied consistently for cannabis use. There is some evidence that alcohol and cannabis use disorder pretransplant could be associated with worse outcomes posttransplantation. However, early liver transplantation for patients with alcohol-associated liver disease in France and in the United States has led to challenges of the 6-mo abstinence rule in Canada in the media. It has also resulted in several legal challenges arguing that the rule violates human rights laws regarding discrimination in the provision of medical services and that the rule is also unconstitutional (this challenge is still before the court). Recent legalization of cannabis use for adults in Canada has led to questions about the appropriateness of limiting transplant access based on cannabis use. The ethics committee of the Canadian Society of Transplantation was asked to provide an ethical analysis of cannabis and alcohol abstinence policies. Our conclusions were as follows: neither cannabis use nor the 6-mo abstinence rule for alcohol use should be an absolute contraindication to transplantation, and transplant could be offered to selected patients, further research should be conducted to ensure evidence-based policies; and the transplant community has a duty not to perpetuate stigma associated with alcohol and cannabis use disorders.

Results of an international crowdsourcing survey on the treatment of non-ST segment elevation ACS patients at high-bleeding risk undergoing percutaneous intervention

AIMS

Choosing an antiplatelet strategy in patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) at high bleeding risk (HBR), undergoing post-percutaneous coronary intervention (PCI), is complex. We used a unique open-source approach (crowdsourcing) to document if practices varied across a small, global cross-section of antiplatelet prescribers in the post-PCI setting.

METHODS AND RESULTS

Five-hundred and fifty-nine professionals from 70 countries (the 'crowd') completed questionnaires containing single- or multi-option and free form questions regarding antiplatelet clinical practice in post-PCI NSTE-ACS patients at HBR. A threshold of 75% defined 'agreement'. There was strong agreement favouring monotherapy with either aspirin or a P2Y₁₂ inhibitor following initial DAPT, within the first year (94%). No agreement was reached on the optimal duration of DAPT or choice of monotherapy: responses were in equipoise for shorter (≤3 months, 51%) or longer (≥6 months, 46%) duration, and monotherapy choice (45% aspirin; 53% P2Y₁₂ inhibitor). Most respondents stated use of guideline-directed tools to assess risk, although clinical judgement was preferred by 32% for assessing bleeding risk and by 46% for thrombotic risk.

CONCLUSION

The crowdsourcing methodology showed potential as a tool to assess current practice and variation on a global scale and to achieve a broad demographic representation. These preliminary results indicate a high degree of variation with respect to duration of DAPT, monotherapy drug of choice following DAPT and how thrombotic and bleeding risk are assessed. Further investigations should concentrate on interrogating practice variation between key demographic groups.

Enhancing Facelift With Simultaneous Submalar Implant Augmentation

BACKGROUND

The midface is particularly prone to the senescent changes of soft tissue ptosis and volume loss, which in individuals with aging or low adiposity can manifest as submalar hollowing. Facelift alone in those with submalar hollowing inadequately addresses the volume loss and may result in a gaunt appearance postoperatively. Submalar implant augmentation is a powerful tool for permanent midface volume restoration for a more youthful and natural contour, as opposed to soft tissue fillers that diminish over time. When performed together, submalar augmentation and facelift synergistically enhance facial rejuvenation results.

OBJECTIVES

Determine the long-term safety and efficacy of submalar implant augmentation as an adjunct to facelift.

METHODS

Retrospective review evaluating results and complications in all consecutive patients who had submalar implant augmentation with SMAS-plication facelift in a single surgeon private practice setting from January 1, 1991, to December 31, 2017.

RESULTS

Forty-eight patients underwent submalar augmentation with simultaneous facelift with an overall satisfaction rate of 95.7%. Complications included 2.1%transient infraorbital hypoesthesia, 1.1% prolonged swelling, and 1.1% capsular contraction that required a minor adjustment under local anesthesia. No infection, implant migration, or extrusion or facial nerve injury occurred.

CONCLUSIONS

Submalar implant augmentation is a safe and effective means of enhancing facelift results through midface volume restoration, subperiosteal release, and improved soft tissue suspension in a more favorable vector. Submalar implant augmentation performed simultaneously with facelift may be an attractive alternative to repeated soft tissue filler or fat injections for patients with submalar hollowing who are interested in facial rejuvenation surgery.

Clinical practices and attitudes regarding the diagnosis and management of heart failure: findings from the CORE Needs Assessment Survey

Aims

CORE is a continuing medical education initiative designed to support the evidence‐based management of heart failure (HF) in the primary and secondary care settings. The goal of the CORE Needs Assessment Survey is to describe current clinical practice patterns and attitudes among global stakeholders in HF care.

Methods and results

The CORE Steering Committee guided the development of survey questions to assess clinical practice, confidence, and attitudes/perceptions among cardiologists, primary care physicians, and nurses involved in HF management. In total, 346 healthcare professionals from Australia (n = 59), Austria (n = 59), Canada (n = 60), Spain (n = 58), Sweden (n = 52), and the UK (n = 58) contributed survey data. Results revealed multiple gaps over the spectrum of HF care, including diagnosis (low recognition of the signs and symptoms of HF and limited use of diagnostic tests), treatment planning (underuse of recommended agents and subtherapeutic dosing), treatment monitoring and adjustment (lack of adherence to recommendations), and long‐term management (low confidence in providing patient education). Although primary care and specialist physicians and nurses shared common unmet needs, healthcare professional‐specific clinical gaps were also identified.

Conclusions

The CORE Needs Assessment Survey provides timely data describing current clinical practices and attitudes among physicians and nurses regarding key aspects of HF care. These findings will be useful for guiding the development of interventions tailored to the specific educational needs of different provider types and designed to support the evidence‐based care of patients with HF.

Successful Isavuconazole therapy in a patient with acute invasive fungal rhinosinusitis and acquired immune deficiency syndrome

OBJECTIVES

To report a case of acute invasive Mucorales rhinosinusitis in a patient with acquired immune deficiency syndrome and diabetes mellitus. To provide a literature review on the role of Isavuconazole in the management of invasive Mucorales rhinosinusitis.

METHODS

A literature review was conducted on August 9, 2015 using PubMed database. The keywords isavuconazole and invasive fungal rhinosinusitis were employed to identify original scientific manuscripts that describe the use of Isavuconazole in patients with invasive fungal rhinosinusitis or rhinocerebral mucormycosis.

RESULTS

The initial search yielded 35 articles with only 1 article (case report) describing the clinical use of Isavuconazole in a patient with invasive Mucorales rhinosinusitis.

CONCLUSIONS

Acute invasive fungal rhinosinusitis is a rare, life-threatening infection with mortality rates reported to range from 30-83%. Successful treatment depends on early surgical debridement, systemic anti-fungal therapy, and correction of predisposing conditions. Isavuconazole (Cresemba), a newly approved antifungal, is safe and clinically effective in treating invasive mucormycosis. This important new therapy should be considered for patients with invasive Mucorales rhinosinusitis that is refractory or intolerant to Amphotericin B.

Integrative genomics positions MKRN1 as a novel ribonucleoprotein within the embryonic stem cell gene regulatory network

In embryonic stem cells (ESCs), gene regulatory networks (GRNs) coordinate gene expression to maintain ESC identity; however, the complete repertoire of factors regulating the ESC state is not fully understood. Our previous temporal microarray analysis of ESC commitment identified the E3 ubiquitin ligase protein Makorin‐1 (MKRN1) as a potential novel component of the ESC GRN. Here, using multilayered systems‐level analyses, we compiled a MKRN1‐centered interactome in undifferentiated ESCs at the proteomic and ribonomic level. Proteomic analyses in undifferentiated ESCs revealed that MKRN1 associates with RNA‐binding proteins, and ensuing RIP‐chip analysis determined that MKRN1 associates with mRNAs encoding functionally related proteins including proteins that function during cellular stress. Subsequent biological validation identified MKRN1 as a novel stress granule‐resident protein, although MKRN1 is not required for stress granule formation, or survival of unstressed ESCs. Thus, our unbiased systems‐level analyses support a role for the E3 ligase MKRN1 as a ribonucleoprotein within the ESC GRN.

Relationship of eosinophils and plasma cells to biofilm in chronic rhinosinusitis

BACKGROUND

This study investigates the relationship of eosinophils and plasma cells to biofilm in chronic rhinosinusitis (CRS). A prospective observational study was performed at the Keck Hospital, University of Southern California, Department of Otolaryngology, Los Angeles, CA.

METHODS

A total of 29 patients, 20 undergoing endoscopic sinus surgery for CRS and 9 control patients undergoing septoplasty for nasal obstruction without history or evidence of CRS, were included in this study. Contiguous sinonasal mucosa sample sections were examined by hematoxylin and eosin (H&E), fluorescence in situ hybridization (FISH), and immunohistochemistry (IHC) for biofilm, microbes, eosinophil major basic protein (EMBP), and cluster designation 27 (CD27). EMBP and CD27 were used as eosinophil and plasma cell markers, respectively.

RESULTS

Biofilm was visualized in 15 of 20 patients with CRS on H&E sections, confirmed by microbial presence using FISH. Biofilm was not identified in tissue samples of the nine control patients. On IHC analysis, CD27 and EMBP expression were significantly higher in patients with CRS compared with control (p < 0.05) and had greater expression in biofilm-positive patients compared with biofilm-negative patients. Nasal polyps correlated with higher expression of CD27 and EMBP, but in CRS patients without polyps CD27 and EMBP was also significantly greater in biofilm-positive specimens compared with biofilm-negative specimens.

CONCLUSION

Biofilm presence in CRS appears to correlate to host inflammatory response involving plasma cell and eosinophil recruitment.

Development of a cyclin-dependent kinase inhibitor devoid of ABC transporter-dependent drug resistance

Background:

Cyclin-dependent kinases (CDKs) control cell cycle progression, RNA transcription and apoptosis, making them attractive targets for anticancer drug development. Unfortunately, CDK inhibitors developed to date have demonstrated variable efficacy.

Methods:

We generated drug-resistant cells by continuous low-dose exposure to a model pyrazolo[1,5-a]pyrimidine CDK inhibitor and investigated potential structural alterations for optimal efficacy.

Results:

We identified induction of the ATP-binding cassette (ABC) transporters, ABCB1 and ABCG2, in resistant cells. Assessment of features involved in the ABC transporter substrate specificity from a compound library revealed high polar surface area (>100 Ų) as a key determinant of transporter interaction. We developed ICEC-0782 that preferentially inhibited CDK2, CDK7 and CDK9 in the nanomolar range. The compound inhibited phosphorylation of CDK substrates and downregulated the short-lived proteins, Mcl-1 and cyclin D1. ICEC-0782 induced G2/M arrest and apoptosis. The permeability and cytotoxicity of ICEC-0782 were unaffected by ABC transporter expression. Following daily oral dosing, the compound inhibited growth of human colon HCT-116 and human breast MCF7 tumour xenografts in vivo by 84% and 94%, respectively.

Conclusion:

We identified a promising pyrazolo[1,5-a]pyrimidine compound devoid of ABC transporter interaction, highly suitable for further preclinical and clinical evaluation for the treatment of cancer.

Abstract 694: Development of selective and potent CDK7 inhibitors for breast cancer therapy

Cyclin dependent kinases (CDK) function as either regulators of cell cycle progression or transcription. CDK7 is unique from other CDKs because it has a dual role in the regulation of cell cycle and transcription making it a desirable target for drug development. It forms a complex with Cyclin H and MAT1 to form the CDK-activating kinase (CAK) that regulates CDK1, CDK2, CDK4 and CDK6, which are important in cell cycle progression. The CAK complex can also act as a transcriptional regulator as part of the TFIIH transcription factor by phosphorylating the COOH-terminal domain of RNA polymerase II (Pol II CTD). In addition, CDK7 as part of the CAK complex can inhibit the phosphorylation of serine 118 on the estrogen receptor (ER), a key player in breast cancer pathogenesis.

Our target validation studies using siRNA have shown that CDK7 reduces growth of the human colorectal cancer cell line, HCT116, induces apoptosis and reduces phosphorylation of key biomarkers (RNA Poll II, CDK1 and CDK2). Using computer modelling of the CDK7 structure, we have designed CDK7 inhibitors, which were selected from a library of pyrazolo [1,5-a]pyrimidine-derived compounds. BS-181, is our first CDK7 inhibitor which inhibits CAK activity with an IC50 of 21 nmol/L. BS-181 has poor pharmacokinetic properties and is not orally bioavailable therefore after extensive studies and chemical modifications we have developed a more potent orally bioavailable CDK7 selective inhibitor, BS-181-L.

Extensive in vitro ADME studies have highlighted that BS-181-L has good aqueous solubility, plasma proteins binding and no hERG liability. BS-181-L inhibits in vivo tumour cell growth in two cancer cell line models, MCF7 and HCT116 cells. In these studies BS-181-L shows no organ and haematological toxicity. We show BS-181-L down regulates key biomarkers in both the peripheral blood mononuclear cells (PBMCs) by flow cytometry and tumour tissue by immunohistochemistry (IHC) and western blotting. In addition, we show that BS-181-L reduces ER activity in reporter assays and ER (serine 118) phosphorylation. Furthermore, combination studies of BS-181-L and anti-estrogens show additive growth inhibitory effects on breast cancer cells.

In summary, here we present data for a potent CDK7 inhibitor, BS-181-L, which has improved CDK7 selectivity, potency and bioavailability from our previously identified CDK7 inhibitor, BS-181. Furthermore, dual inhibition of CDK7 and ER has an additive effect in breast cancer cell growth. Taken together, this data highlights a potential new therapeutic approach for breast cancer.

Citation Format: Hetal Patel, Silvia Ottaviani, Manikandan Periyasamy, Alexander Bondke, Brian Slafer, Richard Starkey, Sebastian H.B Kroll, Sean Delaney, Zahida Zahoor, Matthew J. Fuchter, Anthony G.M Barrett, R. Charles Coombes, Simak Ali. Development of selective and potent CDK7 inhibitors for breast cancer therapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 694. doi:10.1158/1538-7445.AM2013-694

Abstract 700: Gene expression profiling of cyclin-dependent kinase (CDK) inhibition in cancer cells

Cyclin-dependent kinases (CDKs) form complexes with partner cyclins to regulate cell cycle progression and transcription. CDK1, CDK2, CDK4 and CDK6 all regulate cell cycle progression and CDK8 and CDK9 are regulators of transcription. CDK7 is a unique member of this family because it can regulate the cell cycle CDKs as part of the CDK-activating kinase (CAK) and also transcription in conjunction with the TFIIH transcription factor by phosphorylating the COOH-terminal domain of RNA polymerase II (Pol II CTD). A hallmark of cancer is deregulated cell cycle progression and many cancers have abnormal CDK activity which makes CDKs a good target for cancer therapy. Here we show BS-194, a selective and potent CDK inhibitor, which inhibits CDK2, CDK1, CDK5, CDK7 and CDK9 (IC50 = 3, 30, 30, 250 and 90nmol/L, respectively). In vitro cell based assays have shown that BS-194 inhibits the phosphorylation of CDK substrates, Rb and RNA Poll II, down regulation of cyclins A, E and D1 and cell cycle arrest in the S and G2/M phases. BS-194 also has potent anti-proliferative activity in 60 cancer cell lines tested (mean GI50 = 28nmol/L). BS-194 is orally bioavailable and shows potent in vivo tumour growth inhibition of xenograft models of MCF7 and HCT116 cells.

We have used BS-194 as a potent inhibitor of CDK activity in HCT116 cells and performed gene microarray analysis to determine novel pathways and identify novel biomarkers associated with CDK inhibition. In summary, the gene microarray has identified genes differentially expressed in response to BS-194 treatment that are primarily involved in cell cycle, apoptosis and transcription pathways.

Citation Format: Silvia Ottaviani, Sean Delaney, Hetal Patel, Manikandan Periyasamy, Alexander Bondke, Brian Slafer, Richard Starkey, Sebastian H.B. Kroll, Matthew J. Fuchter, Anthony G.M. Barrett, R. Charles Coombes, Simak Ali. Gene expression profiling of cyclin-dependent kinase (CDK) inhibition in cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 700. doi:10.1158/1538-7445.AM2013-700

Genes of primary sulfate assimilation are part of the glucosinolate biosynthetic network in Arabidopsis thaliana

Glucosinolates are plant secondary metabolites involved in responses to biotic stress. The final step of their synthesis is the transfer of a sulfo group from 3'-phosphoadenosine 5'-phosphosulfate (PAPS) onto a desulfo precursor. Thus, glucosinolate synthesis is linked to sulfate assimilation. The sulfate donor for this reaction is synthesized from sulfate in two steps catalyzed by ATP sulfurylase (ATPS) and adenosine 5'-phosphosulfate kinase (APK). Here we demonstrate that R2R3-MYB transcription factors, which are known to regulate both aliphatic and indolic glucosinolate biosynthesis in Arabidopsis thaliana, also control genes of primary sulfate metabolism. Using trans-activation assays we found that two isoforms of APK, APK1, and APK2, are regulated by both classes of glucosinolate MYB transcription factors; whereas two ATPS genes, ATPS1 and ATPS3, are differentially regulated by these two groups of MYB factors. In addition, we show that the adenosine 5'-phosphosulfate reductases APR1, APR2, and APR3, which participate in primary sulfate reduction, are also activated by the MYB factors. These observations were confirmed by analysis of transgenic lines with modulated expression levels of the glucosinolate MYB factors. The changes in transcript levels also affected enzyme activities, the thiol content and the sulfate reduction rate in some of the transgenic plants. Altogether the data revealed that the MYB transcription factors regulate genes of primary sulfate metabolism and that the genes involved in the synthesis of activated sulfate are part of the glucosinolate biosynthesis network.

Correlation of gene and mediator expression with clinical endpoints in an acute interleukin-1beta-driven model of joint pathology

OBJECTIVE

Interleukin-1beta (IL-1beta) plays a key role in the pathogenesis of chronic joint diseases, including osteoarthritis (OA), and drives a cascade of inflammatory and destructive responses within the synovial joint. Animal models of arthritis support the role of IL-1beta in joint pathology, however, the molecular changes downstream of IL-1beta are poorly understood in vivo. This study aimed to evaluate the intra-articular (i.a.) injection of IL-1beta in the rat joint as an acute model of joint disease and associate gene and mediator expression with clinical endpoints and pathological changes.

METHODS

The effects of i.a. administration of a pathologically relevant dose of IL-1beta on joint swelling, mechanical hyperalgesia, histopathology, gene expression and biochemical changes were measured from 2 to 24h.

RESULTS

IL-1beta-induced joint swelling and mechanical hyperalgesia. Gene expression analysis of joint tissue and biochemical analysis of joint lavage fluid identified pro-inflammatory and destructive mediators induced by IL-1beta. Histopathology of joint tissues showed evidence of synovitis and connective tissue inflammation, but not cartilage destruction. However, biochemical analysis of glucosaminoglycan levels in joint lavage fluids indicated cartilage breakdown and might be a sensitive marker of cartilage pathology.

CONCLUSIONS

Intra-articular injection of IL-1beta is a reproducible acute model of joint pathology that is potentially useful to evaluate IL-1 pathway inhibitors. The correlation of molecular events with clinical and pathological changes in this model has enhanced the understanding of the role of IL-1beta in joint disease. Methods developed for gene expression analysis using multi-gene microfluidics cards and for biochemical analysis of joint lavage fluid might have utility for characterisation of other arthritis models and corresponding human disease.

Outcome of Bt transgenes and protein in corn silage, processed grains, and rumen content

The environmental impact of transgenic plants has been questioned due to the potential persistence of proteins encoded by transgenes and horizontal gene transfer from the plant to gut microbes. The outcome of the encoded Bt [cry1A(b)] protein and transgene fragments (CaMV-35S, cry1A(b), bar, and bla) was monitored in silage and processed grains of two commercial Bt11 (NK N44-P4 Bt LL and NK N27-M3 Bt LL) and one Bt176 (Elite N09-K9 Bt) corn hybrids. The three Bt-corn hybrids with their non-Bt isolines were field-grown in four replicates. Seven 1.4-kg capacity mini-silos were prepared per plot and then opened after 1, 2, 4, 8, 16, 32, and 64 d. For each hybrid, two 500-kg plastic bag silos were also prepared, sampled after 30 and 198 d, and used in a feeding trial. In the mini-silos, the transgene fragments could no longer be amplified 32 d after ensiling. In the 500-kg plastic bag silos, the transgene fragments were still detectable in the three Bt hybrid silages 30 and 198 d after ensiling. At ensiling, the Bt protein concentration was 2.69, 4.11, and 0.83 µg g-1 DM for the Bt hybrids N44-P4, N27-M3, and N09-K9, respectively. After 64 d of fermentation in the mini-silos, the concentration was 4, 2, and 1% of the initial concentration, respectively, but was 16, 9, and 9% after 198 d in the 500-kg silos. After stringent processing treatments, transgene fragments, except the bla gene fragment, could still be amplified from corn grains. The Bt protein concentration in corn grain of the three Bt hybrids (initially 61, 239, and 21 ng g-1 DM, respectively) decreased by 35, 74, and 67%, respectively, after micronization, by 92, 98, and 89% after extrusion, and by 100% after flaking. After 7 d of feeding Bt corn silage to six dairy cows, Bt protein increased in ruminal digesta with higher concentrations for Bt11 hybrids than the Bt176 hybrid; in all cases, however, concentrations were very low in forage digesta and below detection levels in rumen fluid. Key words: Transgenic maize, silage, processed grains, genetically modified plants, Bacillus thuringiensis endotoxin

Mite-related bacterial antigens stimulate inflammatory cells in rosacea

BACKGROUND

Patients with papulopustular rosacea have a higher density of Demodex folliculorum mites on their faces than normal subjects but the role, if any, of their mites in initiating inflammation is disputed. Selective antibiotics are effective in reducing the inflammatory changes of papulopustular rosacea, but their mode of action is unknown.

OBJECTIVES

To investigate whether a D. folliculorum-related bacterium was capable of expressing antigens that could stimulate an inflammatory immune response in patients with rosacea.

METHODS

A bacterium (Bacillus oleronius) was isolated from a D. folliculorum mite extracted from the face of a patient with papulopustular rosacea, and was investigated further.

RESULTS

This bacterium produced antigens capable of stimulating peripheral blood mononuclear cells proliferation in 16 of 22 (73%) patients with rosacea but only five of 17 (29%) control subjects (P = 0.0105). This antigenic preparation was fractionated into 70 subfractions and the proteins in each fraction were visualized by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Western blot analysis revealed the presence of two antigenic proteins of size 62 and 83 kDa in fractions when probing with sera from patients with rosacea. No immunoreactivity to these proteins was recorded when probing with sera from control patients. Two-dimensional electrophoretic separation was used to isolate these proteins and matrix-assisted laser desorption/ionization time-of-flight analysis was employed to identify the relevant peptides. The 62-kDa immunoreactive protein shared amino acid sequence homology with an enzyme involved in carbohydrate metabolism and signal transduction while the 83-kDa protein was similar to bacterial heat shock proteins.

CONCLUSIONS

Antigenic proteins related to a bacterium (B. oleronius), isolated from a D. folliculorum mite, have the potential to stimulate an inflammatory response in patients with papulopustular rosacea.

Does an integrated care pathway enhance the management of diabetic ketoacidosis?

AIMS

Integrated Care Pathways (ICPs) are management plans that indicate the sequence and timing of the optimal treatment for individuals with a given disorder. The treatment of diabetic ketoacidosis (DKA) before and after the implementation of an ICP in a teaching hospital was examined.

METHODS

Twenty-seven episodes of DKA were identified during the 13-month control period and 22 in the 13 months following implementation of the ICP. Case notes were reviewed and relevant clinical data extracted.

RESULTS

The introduction of the ICP was associated with a reduction in the time taken to initiate intravenous fluid [45.0 (5-225) min to 37.5 (0-135) min; P = 0.01]. Time taken to initiate insulin infusion was also reduced [60.0 (5-755) min to 37.5 (0-175) min; P = 0.02]. The proportion of patients commenced on intravenous insulin within 60 min increased from 48 to 77% (P = 0.04). In addition, there was a reduction in the prescription of antibiotics (48-18%; P = 0.028) and low molecular weight heparin (59-5%; P < 0.001). Length of stay was not affected.

CONCLUSION

The ICP significantly improved key areas in the management of DKA, although there remains room for further improvements.

Effect of hyperbaric oxygen on oxygen uptake and measurements in the blood and tissues in a normobaric environment

OBJECTIVE

To examine venous partial pressure of oxygen (PvO(2)), transcutaneous oxygen tension (tcPO(2)), and VO(2)MAX in a normobaric environment after a single hyperbaric oxygen (HBO(2)) treatment.

METHODS

This was a prospective study of conditions after the intervention compared with baseline. The participants were 10 moderately trained (VO(2)MAX = 57.6 ml/kg/min) men. Two HBO(2) treatments consisting of breathing 95% oxygen at 2.5 atmospheres absolute (ATA) for 90 minutes were administered on non-consecutive days. Baseline testing included measures of VO(2)MAX, tcPO(2), and anthropometry. At 6.0 (1.0) minutes after the first HBO(2) treatment, a VO(2)MAX test was performed. After the second HBO(2) treatment, leg and chest tcPO(2) and PvO(2) were monitored for 60 minutes.

RESULTS

VO(2)MAX, running time, and peak blood lactate were not altered after the HBO(2) treatment. Leg tcPO(2) was lower (p = 0.003) and chest tcPO(2) was unchanged after the HBO(2) treatment compared with baseline values. PvO(2) was significantly (p<0.001) lower in the first three minutes after treatment than subsequent values, but no other differences were found.

CONCLUSIONS

A single HBO(2) treatment at 2.5 ATA for 90 minutes does not raise PvO(2), tcPO(2), or VO(2)MAX in a normobaric, normoxic environment.

Correlation of photosensitizer delivery to lipoproteins and efficacy in tumor and arthritis mouse models; comparison of lipid-based and Pluronic P123 formulations

PURPOSE

The purpose of this study was the use of animal models to demonstrate the importance of drug delivery (verteporfin) to plasma lipoproteins in order to attain efficacy of photodynamic therapy (PDT) in vivo.

METHODS

Photosensitizers appropriately formulated in various vehicles such as pluronics and lipid-based systems were compared to delivery of the drug in DMSO in two in vivo systems. The first was a tumor model using male DBA/2 mice inoculated intradermally with M1 rhabdomyosarcoma cells and in the second, arthritis in the MRL -lpr mouse strain was enhanced by two intradermal injections of complete Freunds adjunct.

RESULTS

Those formulations in which the drug was in a monomeric form were better able to transfer drug to lipoproteins, which in turn led to superior PDT in vivo.

CONCLUSIONS

The ability to introduce drug in monomeric form into the circulation correlates well with efficacy of photosensitizer formulations in mouse arthritis and tumor models.

Systematic distortions of auditory space perception following prolonged exposure to broadband noise

Perceptual distortions referred to as aftereffects may arise following exposure to an adapting sensory stimulus. The study of aftereffects has a long and distinguished history [Kohler and Wallach, Proc. Am. Philos. Soc. 88, 269-359 (1944)] and a range of aftereffects have been well described in sensory modalities such as the visual system [Barlow, in Vision: Coding and Efficiency (Cambridge University Press, Cambridge, 1990)]. In the visual system these effects have been interpreted as evidence for a population of cells or channels specific for certain features of a stimulus. However there has been relatively little work examining auditory aftereffects, particularly in respect of spatial location. In this study we have examined the effects of a stationary adapting noise stimulus on the subsequent auditory localization in the vicinity of the adapting stimulus. All human subjects in this study were trained to localize short bursts of noise in a darkened anechoic environment. Adaptation was achieved by presenting 4 min of continuous noise at the start of each block of trials and was maintained by a further 15-s noise burst between each trial. The adapting stimulus was located either directly in front of the subject or 30 degrees to the right of the midline. Subjects were required to determine the location of noise burst stimuli (150 ms) in the proximity of the adapting stimulus following each interstimulus period of adaptation. Results demonstrated that following adaptation there was a general radial displacement of perceived sound sources away from the location of the adapting stimulus. These data are more consistent with a channel-based or place-based process of sound localization rather than a simple level-based adaptation model. A simple "distribution shift" model that assumes an array of overlapping spatial channels is advanced to explain the psychophysical data.

The localisation of spectrally restricted sounds by human listeners

The two principal binaural cues to sound location are interaural time differences (ITDs), which are thought to be dominant at low frequencies, and interaural level differences (ILDs), which are thought to dominate at mid to high frequencies. The outer ear also filters the sound in a location dependent manner and provides spectral cues to location. In these experiments we have examined the relative contribution of these cues to the auditory localisation performance by humans. Six subjects localised sounds by pointing their face toward the perceived location of stimuli presented in complete darkness in an anechoic chamber. Control stimuli were spectrally flat (400 Hz to 16 kHz), while the relative contribution of location cues in the low frequency channels was determined using noise high passed at 2 kHz and in the high frequency channels using stimuli low passed at 2 kHz. The removal of frequencies below 2 kHz had little effect on either the pattern of systematic errors or the distribution of localisation estimates with the exception of an increase in the size of the standard deviations associated with a few rear locations. This suggests considerable redundancy in the auditory localisation information contained within a broadband sound. In contrast, restricting the target spectrum to frequencies below 2 kHz resulted in a large increase in the cone-of-confusion errors as well as a subject dependent biasing of the front-to-back or back-to-front confusions. These biases and the reduction in localisation accuracy for high pass stimuli at some posterior locations are consistent with a contribution of spectral information at low frequencies.

A critical evaluation of hepatitis C testing of cadaveric corneal donors

PURPOSE

Enzyme immunoassays (EIAs) for hepatitis C virus (HCV) antibodies used to screen corneal donors are optimized for testing premortem sera. This study evaluated their efficiency when screening cadaveric sera.

METHODS

Abbott HCV EIA 2.0 was used to rescreen 101 cadaveric sera, 70 of which had tested positive and 31 negative by EIA 1.0. Matrix-HCV recombinant immunoblot assay was used as a reference standard. Antibody titers and reactivities were compared in premortem and cadaveric sera. Selected sera from confirmed seropositive donors were screened for virus by polymerase chain reaction (PCR).

RESULTS

HCV EIA 2.0 was 100% sensitive and 92.7% specific. EIA and Matrix-HCV gave similar end-point titers with pre- and postmortem sera. Viral RNA was detected in only three of 15 sera from seropositive donors.

CONCLUSIONS

EIA 2.0 and Matrix-HCV efficiently screen cadaveric sera. However, HCV seropositivity does not necessarily indicate the presence of viral genomes in sera and tissues.

Isolation and genetic mapping of two novel members of the murine Wnt gene family, Wnt11 and Wnt12, and the mapping of Wnt5a and Wnt7a

The murine Wnt genes are implicated in the control of a variety of developmental processes. Using a PCR-based approach, we have isolated two novel members of the murine Wnt gene family, Wnt11 and Wnt12. These cDNAs display an amino acid sequence identity of between 38 and 49% with all other murine Wnts over the regions that we have isolated. In addition, two previously described Wnt genes, Wnt5a and Wnt7a, were detected in RT-PCR products. Interspecific crosses were used to demonstrate close linkage between Wnt12 and Wnt1 on Chromosome (Chr) 15. Wnt7a was mapped to mouse Chr 6, Wnt5a to the centromeric region of Chr 14, and Wnt11 to Chr7.

Sequencing of chromosome I of Saccharomyces cerevisiae: analysis of the 42 kbp SPO7-CENI-CDC15 region

Determination of the DNA sequence and preliminary functional analysis of a 42 kbp centromeric section of chromosome I have been completed. The section spans the SPO7-CEN1-CDC15 loci and contains 19 open reading frames (ORFs). They include an apparently inactive Ty1 retrotransposon and eight new ORFs with no known homologs or function. The remaining ten genes have been previously characterized since this part of the yeast genome has been studied in an unusually intensive manner. Our directed sequencing allows a complete ordering of the region.

Transmission of hepatitis C by kidney transplantation--the risks

The use of cadaveric organ donors with positive serologic tests for hepatitis C (HCV) has caused considerable debate. We have reviewed the clinical course of 43 EIA1 HCV-negative recipients who received kidney transplants from EIA1 HCV-positive donors (Study). We have attempted to define the rate of HCV-RNA transmission and to determine the frequency of HCV disease transmission as determined by abnormalities in liver function tests. Viral transmission was assessed using serologic assays for HCV antibody formation (EIA1, EIA2, and Matrix--an automated multiple antigen immunoblot assay) and with PCR testing for the presence of HCV-RNA on recipient sera. Liver function was followed longitudinally in the Study patients and compared with a group of 103 kidney recipients of organs from EIA1 HCV-negative donors (Control). Of the Study patients, 56% became PCR-positive for HCV-RNA, suggesting the transmission of HCV-RNA from the HCV-positive donor. Interpretation of serologic tests for HCV was complex. Currently available first (EIA1) and second (EIA2) generation serologic assays were always negative. The multiple antigen immunoblots assay (Matrix) had a high positive predictive value (93%) for the presence of HCV-RNA transmission, but one-third of Matrix-negative Study patients were PCR-positive (sensitivity = 66%). Currently, only 38% of recipients have HCV-RNA, suggesting that the virus may have been cleared by one-third of Study recipients who had circulating virus. Traditional tests of liver function (ALT, AST, AP, and GGT) were of limited use in predicting HCV-RNA transmission. Average AST, AP, and GGT were similar in the two groups. Average ALT was increased (93 I/U and 47 I/U) in Study and Control patients, respectively, but this difference was not significant. Episodes of abnormal liver function (ALT 60-99 IU for > or = 14 days) occurred in 22% of Study and 10% of Control patients (P = NS) and lasted longer in Study compared with Control patients (301 vs. 138 days; P < 0.02). Hepatitis (ALT > or = 100 IU for > 14 days) occurred with an equal frequency (6.5%) in both groups. The presence of HCV-RNA did not predict episodes of abnormal liver function. Fulminant hepatitis or rapidly progressive cirrhosis did not occur in the recipients of organs from HCV-positive donors. These data demonstrate a high efficiency of transfer of HCV-RNA by kidney transplantation from an HCV-positive donor to an HCV-negative recipient. A majority of the patients have asymptomatic HCV infection.(ABSTRACT TRUNCATED AT 400 WORDS)

SKN1 and KRE6 define a pair of functional homologs encoding putative membrane proteins involved in beta-glucan synthesis

KRE6 encodes a predicted type II membrane protein which, when disrupted, results in a slowly growing, killer toxin-resistant mutant possessing half the normal level of a structurally wild-type cell wall (1-->6)-beta-glucan (T. Roemer and H. Bussey, Proc. Natl. Acad. Sci. USA 88:11295-11299, 1991). The mutant phenotype and structure of the KRE6 gene product, Kre6p, suggest that it may be a beta-glucan synthase component, implying that (1-->6)-beta-glucan synthesis in Saccharomyces cerevisiae is functionally redundant. To examine this possibility, we screened a multicopy genomic library for suppression of both the slow-growth and killer resistance phenotypes of a kre6 mutant and identified SKN1, which encodes a protein sharing 66% overall identity to Kre6p. SKN1 suppresses kre6 null alleles in a dose-dependent manner, though disruption of the SKN1 locus has no effect on killer sensitivity, growth, or (1-->6)-beta-glucan levels. skn1 kre6 double disruptants, however, showed a dramatic reduction in both (1-->6)-beta-glucan levels and growth rate compared with either single disruptant. Moreover, the residual (1-->6)-beta-glucan polymer in skn1 kre6 double mutants is smaller in size and altered in structure. Since single disruptions of these genes lead to structurally wild-type (1-->6)-beta-glucan polymers, Kre6p and Skn1p appear to function independently, possibly in parallel, in (1-->6)-beta-glucan biosynthesis.

Physical localization of yeast CYS3, a gene whose product resembles the rat gamma-cystathionase and Escherichia coli cystathionine gamma-synthase enzymes

We have cloned, sequenced and physically mapped the CYS3 gene of Saccharomyces cerevisiae. This gene can complement the cys3-1 allele, and disruptions at this locus lead to cysteine auxotrophy. The predicted CYS3 product is closely related (46% identical) to the rat cystathionine gamma-lyase (Erickson et al., 1990), but differs in lacking cysteine residues. These results provide further evidence that the S288C strain of yeast resembles mammals in synthesizing cysteine solely via a trans-sulfuration pathway. The CYS3 product was found to have strong homology to three other enzymes involved in cysteine metabolism: the Escherichia coli metB and metC products and the S. cerevisiae MET25 gene product. The trans-sulfuration enzymes appear to form a diverged family and carry out related functions from bacteria to mammals.

Sequencing of chromosome I from Saccharomyces cerevisiae: analysis of a 32 kb region between the LTE1 and SPO7 genes

The DNA sequencing and preliminary functional analysis of a 32 kb section of yeast chromosome I has been completed. This region lies on the left arm of the chromosome between the LTE1 and SPO7 genes and contains 14 open reading frames (ORFs) positioned closely together, with an average spacing of approximately 350 nucleotides between coding regions. Three of these ORFs correspond to previously identified genes, a further three show significant homology with other proteins, while the remaining eight ORFs share no significant homology to genes in the databases.

Antibody to HIV-1, HTLV-I, and HCV in three populations of rural Haitians

The seroprevalence of antibodies to HIV-1, HTLV-I, and HCV was evaluated in three populations from northern rural Haiti: 1,727 patients attending the hospital for symptoms suggestive of HIV disease, 228 consecutive surgical patients, and 500 pregnant women were tested. HIV-1 seroprevalence was 6.1 and 4.0% in the last two groups, respectively, and 39.3% in the symptomatic population. Associated symptoms of wasting, cough, and diarrhea and a clinical diagnosis of AIDS were significantly predictive of HIV-1 seropositivity. Antibody to HTLV-I seroprevalence ranged from 2.2-5.3% in pregnant women, surgical patients, and HIV-seronegative symptomatic patients and was similar among the three groups when stratified by age. In contrast, HIV-1 seropositivity and HTLV-I seropositivity were significantly associated. The prevalence of confirmed antibody to HCV was low and not associated with either HIV-1 or HTLV-I seropositivity.

The effect of gamma-irradiation on the toxicity of malathion in V79 Chinese hamster cells and Molt-4 human lymphocytes

There is growing interest in the irradiation of food and agricultural products for insect disinfestation, sprout inhibition, delayed ripening and the reduction of microbiological loads. Extensive research has been done on this process, and irradiation to a maximum dose of 10 kGy is recognized as safe by national and international regulatory agencies. The question has been raised, however, whether irradiation of pesticide residues might produce radiation products that were more toxic or less toxic than the original pesticide. To address this question, we observed the effects of 10 kGy of gamma-radiation on malathion as measured by sister-chromatid exchange (SCE), micronuclei formation, cell survival, growth rate and polyploid formation. We found no significant differences between the effects of irradiated and unirradiated malathion on any of these end-points. Polyploid formation was the most dramatic effect of both irradiated and control malathion on V79 Chinese hamster cells. Cell survival, polyploid formation and growth rate were slightly better in cells treated with irradiated malathion. In Molt-4 human lymphocyte cells, micronuclei formation was not affected by irradiated or unirradiated malathion. Compared to malathion alone, the lack of such biological effects indicates that none of the presumed radiation-induced breakdown products increased or decreased the endpoints studied. The number of SCE was consistently, but not significantly, higher in the cells treated with irradiated malathion. There were no significant differences in cell survival or micronucleus formation in the human lymphocyte cell line Molt-4 treated with irradiated or control malathion. Thus, the irradiation of the pesticide malathion to 10 kGy, a recommended upper dose for most food irradiations, does not significantly alter its toxicity in these in vitro systems.

A comparison of two supplemental procedures for confirmation of antibody to hepatitis C virus c100-3 antigen in Louisiana blood donors

In a pilot study designed to evaluate the performance of supplemental hepatitis C virus (HCV) tests, 146 consecutive HCV enzyme immunoassay (EIA)-reactive samples (0.98% of 14,949 donors) were comparatively evaluated with two sets of supplemental tests: HCV antibody neutralization/c100-3 peptide EIA and the first-generation HCV recombinant immunoblot assay (RIBA). Of these samples, 68.5 percent were positive and 17.8 percent were negative on both supplemental assays. Nineteen samples were discordant. Eleven samples were positive on one assay (9 on neutralization/peptide, 2 on RIBA) and negative or indeterminate on the alternate supplemental test, but reacted with two additional HCV antigens outside the c100-3 region in a second-generation dot immunoblot assay. The dot immunoblot assay was used as a reference and reactive samples were considered confirmed. The remaining eight discordant samples were indeterminate or negative on either assay and did not react on the dot immunoblot assay. These data indicate a 0.74-percent prevalence of HCV exposure detected by reactivity with the c100-3 antigen in blood donors in southern Louisiana.

Comparative evaluation of supplemental hepatitis C virus antibody test systems

Implementation of routine blood donor screening using anti-hepatitis C virus (HCV) enzyme immunoassay (EIA) has resulted in an urgent need for well-characterized supplemental assays to confirm the presence of HCV antibodies. A comparative study of four commercially available supplemental assays is reported here: first- and second-generation versions of a strip recombinant immunoblot assay (RIBA-1 and RIBA-2), an HCV neutralization EIA, and HCV neutralization plus synthetic peptide EIA. Three hundred sixty-seven blood donor specimens that were repeatedly reactive on HCV EIA were studied. Most specimens (93%) were also evaluated by radioimmunoassay (RIA) with a six-antigen panel, and 60 selected specimens were tested for HCV RNA by the polymerase chain reaction (PCR). RIBA-1 and RIBA-2 gave concordant results with 86 percent of specimens, while an additional 13 percent were correctly classified by RIBA-2 but not RIBA-1. Neutralization EIA alone correctly identified 94 percent of the study group, while the remaining 6 percent required the peptide EIA or the combined neutralization-peptide assay system for correct classification. The RIBA-2 and neutralization-peptide assay system for correct classification. The RIBA-2 and neutralization-peptide assay systems yielded identical results for 86 percent of specimens, and these results were supported by RIA and selected PCR testing. Only 2 specimens (0.5%) were frankly discrepant, while 51 specimens were indeterminate on either (47) or both (4) assays. When either the RIBA-2 or neutralization-peptide assay yielded an indeterminate interpretation, the other system correctly classified the specimen (based on concordance with RIA and PCR data) in a high proportion (92%) of cases.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of colcemid on the heat survival of mitotic V79 Chinese hamster cells

V79 Chinese hamster cells were collected by colcemid addition to study the effect of heat on mitosis. When they were heated at 42 degrees C and 45 degrees C in the presence of 0.06 micrograms/mL colcemid, cell survival increased over the control samples, which were heated in ordinary medium. Scanning electron microscopy showed that cells heated to 45 degrees C in the presence or absence of colcemid had fewer microvilli on the surface, but they did not have increased bleb formation. Transmission electron microscopy showed that the chromatin was diffuse in the heated cells and the kinetochores were indistinct. The mitochondria in the heated cells were also swollen and contained visible particles.

The effect of a chimeric mouse-human CD7 antibody on human T, natural killer, and lymphokine-activated killer cell activity in vitro

A chimeric CD7 antibody has been constructed with mouse variable and human constant regions and is currently being assessed in the prophylaxis of renal graft rejection. In this study we have investigated if this antibody or its murine parental form inhibits the function of a number of immune effector mechanisms involved in host defense against infection and/or malignancy. Most memory T cells and all natural killer cells express the CD7 antigen and could therefore be affected by CD7 antibody. Murine and chimeric CD7 antibodies significantly inhibit the alloproliferation of naive (65 +/- 4% and 66 +/- 8%, respectively) but not memory T cells (86 +/- 2% and 98 +/- 4%, respectively) in a primary mixed lymphocyte reaction relative to the negative control CD10 antibody (P less than 0.001). The memory T cell proliferative response to recall antigen is also largely unaffected by murine and chimeric CD7 antibodies relative to the negative control antibody (91 +/- 12% and 103 +/- 10%, respectively). The CD7 antigen is almost completely modulated from the surface of NK cells after incubation for 24 hr with either the murine or chimeric CD7, but not the CD10, negative control. The modulation of CD7 antigen by antibody, however, does not affect the cytotoxic function of either the NK or lymphokine-activated killer cells significantly. Preincubation with the chimeric antibody however, consistently showed a small inhibition relative to the negative control of 75-80% in NK assays and to 80-90% in LAK assays. These data suggest that both murine and chimeric CD7 antibodies may have a selective effect on alloproliferation but may largely spare a major component of the host's innate immunity as well as memory T cell proliferation to previously encountered antigens.

L-[3H]adenosine, a new metabolically stable enantiomeric probe for adenosine transport systems in rat brain synaptoneurosomes

The stereoenantimers D-[3H]adenosine and L-[3H]adenosine were used to study adenosine accumulation in rat cerebral cortical synaptoneurosomes. L-Adenosine very weakly inhibited rat brain adenosine deaminase (ADA) activity with a Ki value of 385 microM. It did not inhibit rat brain adenosine kinase (AK) activity, nor was it utilized as a substrate for either ADA or AK. The rate constants (fmol/mg of protein/s) for L-[3H]adenosine accumulation measured in assays where transport was stopped either with inhibitor-stop centrifugation or with rapid filtration methods were 82 +/- 14 and 75 +/- 10, respectively. Using the filtration method, the rates of L-[3H]adenosine accumulation were not significantly different from the value of 105 +/- 15 fmol/mg of protein/s measured for D-[3H]adenosine transport. Unlabeled D-adenosine and nitrobenzylthiolnosine, both at a concentration of 100 microM, reduced the levels and rates of L-[3H]adenosine accumulation by greater than 44%. These findings suggest that L-adenosine, a metabolically stable enantiomeric analog, and the naturally occurring D-adenosine are both taken up by rat brain synaptoneurosomes by similar processes, and as such L-adenosine may represent an important new probe with which adenosine uptake may be studied.