Enhancing the Small-Scale Screenable Biological Space beyond Known Chemogenomics Libraries with Gray Chemical Matter─Compounds with Novel Mechanisms from High-Throughput Screening Profiles

Phenotypic assays have become an established approach to drug discovery. Greater disease relevance is often achieved through cellular models with increased complexity and more detailed readouts, such as gene expression or advanced imaging. However, the intricate nature and cost of these assays impose limitations on their screening capacity, often restricting screens to well-characterized small compound sets such as chemogenomics libraries. Here, we outline a cheminformatics approach to identify a small set of compounds with likely novel mechanisms of action (MoAs), expanding the MoA search space for throughput limited phenotypic assays. Our approach is based on mining existing large-scale, phenotypic high-throughput screening (HTS) data. It enables the identification of chemotypes that exhibit selectivity across multiple cell-based assays, which are characterized by persistent and broad structure activity relationships (SAR). We validate the effectiveness of our approach in broad cellular profiling assays (Cell Painting, DRUG-seq, and Promotor Signature Profiling) and chemical proteomics experiments. These experiments revealed that the compounds behave similarly to known chemogenetic libraries, but with a notable bias toward novel protein targets. To foster collaboration and advance research in this area, we have curated a public set of such compounds based on the PubChem BioAssay dataset and made it available for use by the scientific community.

Activation of human STING by a molecular glue-like compound

Stimulator of interferon genes (STING) is a dimeric transmembrane adapter protein that plays a key role in the human innate immune response to infection and has been therapeutically exploited for its antitumor activity. The activation of STING requires its high-order oligomerization, which could be induced by binding of the endogenous ligand, cGAMP, to the cytosolic ligand-binding domain. Here we report the discovery through functional screens of a class of compounds, named NVS-STGs, that activate human STING. Our cryo-EM structures show that NVS-STG2 induces the high-order oligomerization of human STING by binding to a pocket between the transmembrane domains of the neighboring STING dimers, effectively acting as a molecular glue. Our functional assays showed that NVS-STG2 could elicit potent STING-mediated immune responses in cells and antitumor activities in animal models.

Intra-Operative Radiotherapy (IORT) in Breast Conserving Therapy in Early-Stage Breast Cancer and DCIS

PURPOSE/OBJECTIVE(S)

Initial breast intra-operative radiotherapy (IORT) results in clinical trials were encouraging though with longer follow up, increased local recurrences have been reported compared with whole breast radiation or other partial breast radiation including accelerated partial breast irradiation (APBI) methods. The goal of the study is to report our prospective single institution IORT breast study outcomes of local recurrence (LR) including true recurrence and breast elsewhere failures, breast cancer specific survival (BCSS), and overall survival (OS) with low energy x-ray IORT in early-stage breast cancer or ductal carcinoma in situ.

MATERIALS/METHODS

A total of 480 patients with early-stage breast cancer or DCIS were prospectively enrolled in an IRB approved single institution trial and treated with low energy X-ray IORT 20 Gy at time of breast-conserving surgery. Eligibility criteria included ≥ 45 years of age with unifocal tumors < 3 cm deemed candidates for partial mastectomy. Supplemental external beam radiation was recommended for patients with high-risk surgical pathology including multifocal disease, positive nodes, close margins < 2 mm, or lymphovascular invasion. Ipsilateral breast tumor recurrences were classified as true recurrence versus elsewhere failure by location and histology: same/different quadrant and similar/different histology. Kaplan-Meier methods were used to estimate survival probabilities across time.

RESULTS

Median age of enrolled patients was 64 years with the majority of patients having favorable phenotype with 94% ER+ and 93% Her-2 - disease. 110 patients (23%) had supplemental EBRT delivered; 103 to the whole breast and 7 to the breast and regional nodes. At a median follow up of 73 months (range 17 - 131 months), there were 23 (4.8%) ipsilateral breast tumor recurrences, of which 9 were true recurrences (1.9%) and 14 elsewhere failures (2.9%). One patient with true recurrence and 3 patients with elsewhere breast failures synchronously presented with clinical or radiographic regional node involvement. Seven patient developed contralateral breast cancer and 8 patients developed distant metastases during the follow-up period. There were 2 breast cancer related deaths. At 6-years, overall survival rate was 96.8% and breast cancer specific survival was 98.7%.

CONCLUSION

Our study outcomes reflect similar outcomes as other reported IORT studies with electron or low energy X-ray in breast cancer, with higher risk of local failure than historical whole breast and other partial breast radiation techniques. This supports current radiation society guidelines for IORT monotherapy for breast cancer to be optimally considered in the context of prospective clinical trials.

Data Driven Approach to Exactrac Setup Parameters after CBCT for Cranial Radiotherapy

PURPOSE/OBJECTIVE(S)

The purpose of this study is to 1) Determine the congruence of shifts derived from Cone-Beam CT (CBCT) and from Exactrac dynamic KV X-rays 2) To setup action levels for Exactrac imaging to determine if patient potentially moved between CBCT and Exactrac acquisition and 3) To analyze if Exactrac alone can be reliably used for cranial setup forgoing the CBCT step MATERIALS/METHODS: Exactrac dynamic, uses in-room KV X-ray imaging that is mounted on the floor to monitor patient positioning during treatment. The congruence of imaging and radiation isocenter for the LINAC and Exactrac system was verified using the Winston-Lutz (WL) test over a period of one year. The WL pointer was set up and its coincidence with imaging and radiation isocenter was confirmed. Exactrac images were then acquired at various couch angles and the pointer deviation from Exactrac imaging isocenter is noted. Secondly, translation and rotation shifts for 175 consecutive cranial cases were examined to determine the deviation between shifts as denoted by CBCT and Exactrac. These patients were initially set up using CBCT and then once in treatment position, Exactrac KV images were acquired to check for any deviation. The deviation between the two systems was collected and a Kolomogorov-Smirnov (KS) test was performed on the data to check for the normality of the distribution. Statistical Process Control (SPC) was performed to derive action levels for Exactrac based shifts after CBCT.

RESULTS

Based on repeated Winston-Lutz tests over a period of one year, the maximum deviation between radiation and imaging isocenters and Exactrac isocenter was 0.3mm and 0.3 deg over all couch angles. This number remained stable over the entire time period without necessitating any recalibration of Exactrac isocenter. Based on patient data for cranial cases, the mean and standard deviations for the largest shifts were (0.45 mm, 0.40 mm) for translations (range 0 - 2.03mm) and (0.44 deg and 0.32 deg) for rotations (range 0 - 2.21 degree). Using SPC, it was decided that the action level for translations and rotations could be set to 0.8mm and 0.5 deg respectively. Any deviation beyond this action level necessitates re-imaging to verify that the patient did not move in between the CBCT and Exactrac imaging acquisitions CONCLUSION: Exactrac system derived shifts show excellent agreement with CBCT. The isocentricity of the systems is maintained over a long period of time and shows no drift. Either system can be reliably used to set up cranial patients. With the added advantage of speed of acquisition, matching and shifts, the Exactrac system could replace CBCT for daily setup of patients undergoing cranial radiotherapy.

Safety and immunogenicity of the epicutaneous reactivation of pertussis toxin immunity in healthy adults: a phase I, randomized, double-blind, placebo-controlled trial

OBJECTIVES

Protection induced by acellular vaccines can be short, requiring novel immunization strategies. Objectives of this study were to evaluate safety and capacity of a recombinant pertussis toxin (PTgen) -coated Viaskin® epicutaneous patch to recall memory responses in healthy adults.

METHODS

This double-blind, placebo-controlled randomized trial (Phase I) assessed the safety and immunogenicity of PTgen administered on days 0 and 14 to healthy adults using Viaskin® patches applied directly or after epidermal laser-based skin preparation. Patch administration was followed by Boostrix®dTpa on day 42. Antibodies were assessed at days 0, 14, 28, 42 and 70.

RESULTS

Among 102 volunteers enrolled, 80 received Viaskin-PT (Viaskin-PT 25 μg (n = 25), Viaskin-PT 50 μg (n = 25), laser + Viaskin-PT 25 μg (n = 5), laser + Viaskin-PT 50 μg (n = 25)), Viaskin-placebo (n = 10) or laser + Viaskin-placebo (n = 2). Incidence of adverse events was similar across groups (any local event: 21/25 (84.0%), 24/25 (96.0%), 4/5 (80.0%), 24/25 (96.0%), 8/10 (80.0%), 10/12 (83.0%), respectively). Direct application induced no detectable response. On day 42, PT-IgG geometric mean concentrations were significantly higher following laser + Viaskin-PT 25 μg and 50 μg (139.87 (95% CI 87.30-224.10) and 121.76 (95% CI 95.04-156.00), respectively), than laser + Viaskin-placebo (59.49, 95% CI 39.37-89.90). Seroresponse rates were higher following laser + Viaskin-PT 25 μg (4/5 (80.0%), 95% CI 28.4-99.5) and 50 μg (22/25 (88.0%), 95% CI 68.8-97.5) than laser + Viaskin-placebo (0/12 (0.0%), 95% CI 0.0-26.5).

CONCLUSIONS

Viaskin-PT applied after laser-based epidermal skin preparation showed encouraging safety and immunogenicity results: anti-PT booster responses were not inferior to those elicited by Boostrix®dTpa. This study is registered at ClinicalTrials.gov (NCT03035370) and was funded by DBV Technologies.

Rapid and sensitive diagnostic procedure for multiple detection of pandemic Coronaviridae family members SARS-CoV-2, SARS-CoV, MERS-CoV and HCoV: a translational research and cooperation between the Phan Chau Trinh University in Vietnam and University of Bari "Aldo Moro" in Italy

OBJECTIVE

A new pandemic coronavirus causing coronavirus disease-2019 (COVID-19), initially called 2019-nCoV and successively named Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The COVID-19 refers to the disease while the SARS-CoV-2 refers to the virus and is characterized by a rapid contagious capacity able to spread worldwide in a very short time. The rise in the number of infected patients and deaths is of great concern especially because symptoms are vague and similar to other forms of flu infection and corona syndrome infections characterized by fever, fatigue, dry cough, and dyspnea. According to the latest guidelines published by the World Health Organization (WHO), the diagnosis of COVID-19 must be confirmed by quantitative reverse transcription polymerase chain reaction (rRT-PCR) or gene sequencing of specimen obtained from throat, sputum and blood samples. However, the limitations due to logistics, as well as low sensitivity and specificity diagnostic tools currently available have been reported as the main cause of high incidence of either false-negative or positive results.

PATIENTS AND METHODS

The purpose of the present translational research protocol is to discuss and present the original findings from our research team on new diagnostic technique to detect four Coronaviridae family members (SARS-CoV-2, SARS-CoV, HCoV and MERS-CoV), highlighting the methodology, the procedure and the possible advantages. Moreover, the authors review the current epidemiology, precautions and safety measures for health personnel to manage patients with known or suspected COVID-19 infection.

RESULTS

Implementation of an effective and rapid plan of diagnosing, screening and checking is a key factor to reduce and prevent further transmission. This procedure based on rRT-PCR could be of great help to decisively validate the results obtained from more conventional diagnostic procedures such as chest computed tomography (CT) imaging and chest ultrasound.

CONCLUSIONS

This translational diagnostic tool will assist emergency and primary care clinicians, as well as out-of-hospital providers, in effectively managing people with suspected or confirmed SARS-CoV-2.

Previously Uncharacterized Vacuolar-type ATPase Binding Site Discovered from Structurally Similar Compounds with Distinct Mechanisms of Action

Using a comprehensive chemical genetics approach, we identified a member of the lignan natural product family, HTP-013, which exhibited significant cytotoxicity across various cancer cell lines. Correlation of compound activity across a panel of reporter gene assays suggested the vacuolar-type ATPase (v-ATPase) as a potential target for this compound. Additional cellular studies and a yeast haploinsufficiency screen strongly supported this finding. Competitive photoaffinity labeling experiments demonstrated that the ATP6V0A2 subunit of the v-ATPase complex binds directly to HTP-013, and further mutagenesis library screening identified resistance-conferring mutations in ATP6V0A2. The positions of these mutations suggest the molecule binds a novel pocket within the domain of the v-ATPase complex responsible for proton translocation. While other mechanisms of v-ATPase regulation have been described, such as dissociation of the complex or inhibition by natural products including bafilomycin A1 and concanamycin, this work provides detailed insight into a distinct binding pocket within the v-ATPase complex.

Female black flies of Simulium (Diptera: Simuliidae) collected on humans in Tam Dao National Park, Vietnam: description of a new species and notes on four species newly recorded from Vietnam

A total of 29 female black flies were captured by a hand net as they swarmed around humans in Tam Dao National Park, Vinh Phuc Province, Vietnam. They included one species of the subgenus Gomphostilbia (Simulium (Gomphostilbia) asakoae Takaoka & Davies) and five species of the subgenus Simulium, of which one species is described as Simulium (Simulium) vietnamense sp. nov. and the other four species (S. (S.) chungi Takaoka & Huang, S. (S.) grossifilum Takaoka & Davies, S. (S.) maenoi Takaoka & Choochote, and S. (S.) rufibasis Brunetti) are newly recorded from Vietnam.

Mesenchymal stem/progenitor cell isolation from tooth extraction sockets

Bone marrow-derived mesenchymal stem/progenitor cells (BMSCs) are commonly used in regeneration therapy. The current primary source of BMSCs is the iliac crest; however, the procedure is associated with various burdens on the patient, including the risk of pain and infection. Hence, the possibility to collect BMSCs from other, more accessible, sources would be an attractive approach. It is well known that stem cells migrate from surrounding tissues and play important roles in wound healing. We thus hypothesized that stem/progenitor cells could be isolated from granulation tissue in the dental socket, and we subsequently collected granulation tissue from dog dental socket 3 d after tooth extraction. After enzyme digestion of the collected tissue, the cells forming colonies constituted the dental socket-derived stem/progenitor cells (dDSCs). Next, dDSCs were compared with dog BMSCs (dBMSCs) for phenotype characterization. A flow cytometric analysis showed that dDSCs were positive for CD44, CD90, and CD271 but negative for CD34 and CD45, similar to dBMSCs. dDSCs also exhibited osteogenic, adipogenic, and chondrogenic differentiation ability, similar to dBMSCs, with a higher capacity for colony formation, proliferation, and motility than dBMSCs. In addition, an in vivo ectopic bone formation assay showed that dDSCs and dBMSCs both induced hard tissue formation, although only dDSCs formed a fibrous tissue-like structure connected to the newly formed bone. Finally, we tested the ability of dDSCs to regenerate periodontal tissue in a one-wall defect model. The defects in the dDSC-transplanted group (β-TCP/PGA/dDSCs) were regenerated with cementum-like and periodontal ligament-like tissues and alveolar bone, whereas only bony tissue was observed in the control group (β-TCP/PGA). In conclusion, we identified and characterized a population of stem/progenitor cells in granulation tissue obtained from the dental socket that exhibited several characteristics similar to those of BMSCs. Dental sockets could therefore be a novel source for isolating stem/progenitor cells from bone.

Clinical dyslipidaemia is associated with changes in the lipid composition and inflammatory properties of apolipoprotein-B-containing lipoproteins from women with type 2 diabetes

AIMS/HYPOTHESIS

The aim of this study was to use lipidomics to determine if the lipid composition of apolipoprotein-B-containing lipoproteins is modified by dyslipidaemia in type 2 diabetes and if any of the identified changes potentially have biological relevance in the pathophysiology of type 2 diabetes.

METHODS

VLDL and LDL from normolipidaemic and dyslipidaemic type 2 diabetic women and controls were isolated and quantified with HPLC and mass spectrometry. A detailed molecular characterisation of VLDL triacylglycerols (TAG) was also performed using the novel ozone-induced dissociation method, which allowed us to distinguish vaccenic acid (C18:1 n-7) from oleic acid (C18:1 n-9) in specific TAG species.

RESULTS

Lipid class composition was very similar in VLDL and LDL from normolipidaemic type 2 diabetic and control participants. By contrast, dyslipidaemia was associated with significant changes in both lipid classes (e.g. increased diacylglycerols) and lipid species (e.g. increased C16:1 and C20:3 in phosphatidylcholine and cholesteryl ester and increased C16:0 [palmitic acid] and vaccenic acid in TAG). Levels of palmitic acid in VLDL and LDL TAG correlated with insulin resistance, and VLDL TAG enriched in palmitic acid promoted increased secretion of proinflammatory mediators from human smooth muscle cells.

CONCLUSIONS

We showed that dyslipidaemia is associated with major changes in both lipid class and lipid species composition in VLDL and LDL from women with type 2 diabetes. In addition, we identified specific molecular lipid species that both correlate with clinical variables and are proinflammatory. Our study thus shows the potential of advanced lipidomic methods to further understand the pathophysiology of type 2 diabetes.

Flavonoids differentially inhibit guinea pig epidermal cytosolic phospholipase A2

Cytosolic phospholipase A2 (cPLA2) is believed to involve the regulation of essential cellular processes. Like other cell types, epidermal cPLA2 may participate in various metabolic processes including eicosanoid generation. In this investigation, we demonstrated the presence of cPLA2 in guinea pig epidermis. The epidermal cPLA2 is Ca2+-dependent, active at micromolar concentration of Ca2+ and resistant to disulfide-reducing agents. Furthermore, it is inhibited by methyl arachidonyl fluorophosphonate (MAFP), a selective inhibitor of cPLA2, while 12-epi-scalardial (a sPLA2 inhibitor) did not cause inhibition. A test of several flavonoids revealed that quercetin (flavonol) weakly inhibited cPLA2, while flavanone had negligible inhibitory activity. In contrast, amentoflavone and ginkgetin (biflavones) markedly inhibited cPLA2 activity in the epidermis. These results underscore that different flavonoids do vary in their capability to exert differential effects on arachidonate metabolism in the skin via modulation of epidermal cPLA2 activity.

A prominent role for activator protein-1 in the transcription of the human 2B4 (CD244) gene in NK cells

The cell surface glycoprotein 2B4 (CD244) of the Ig superfamily is involved in the regulation of NK and T lymphocyte functions. We have recently identified CD48 as the high affinity counterreceptor for 2B4 in both mice and humans. The cytoplasmic domain of 2B4 associates with src homology 2 domain-containing protein or signaling lymphocyte activation molecule-associated protein, whose mutation is the underlying genetic defect in the X-linked lymphoproliferative syndrome. In this study, we report the molecular cloning and characterization of the human 2B4 (h2B4) promoter. Through primer extension analysis, we found that the transcription of the h2B4 gene initiates at multiple start sites. We isolated h2B4 genomic clones and PCR amplified the 5' untranslated region containing the promoter elements. We have identified a functional AP-1 site that lies between (-106 to -100) through transient transfection analysis in YT cells, a human NK cell line. EMSAs with Abs specific for various protein factors of the AP-1 family revealed that multiple members of the Jun family are involved in the regulation of the h2B4 gene. Mutation of the AP-1 site not only abolishes protein/DNA interactions but also promoter activity. These results demonstrate a significant role for AP-1 in the transcriptional regulation of the h2B4 gene.

Alterations in protein phosphatase 2A subunit interaction in human carcinomas of the lung and colon with mutations in the A beta subunit gene

Protein phosphatase 2A (PP2A) consists of three subunits, A, B and C. The A and B subunits have regulatory functions while C is the catalytic subunit. PP2A core enzyme is composed of subunits A and C, and the holoenzyme of subunits A, B and C. All subunits exist as multiple isoforms or splice variants. The A subunit exists as two isoforms, A alpha and A beta. Here we report about the properties of eight A beta mutants, which were found in human lung and colon cancer. These mutants were reconstructed by site-directed mutagenesis and assayed for their ability to bind B and C subunits. Two mutants showed decreased binding of PR72, a member of the B" family of B subunits, but normal C subunit binding; two mutants exhibited decreased binding of the C subunit and of B"/PR72; and one mutant showed increased binding of both the C subunit and B"/PR72. Of three mutants that behaved like the wild-type A beta subunit, one is a polymorphic variant and another one is altered outside the binding region for B and C subunits. Importantly, we also found that the wild-type A alpha and A beta isoforms, although 85% identical, are remarkably different in their ability to bind B and C subunits. Our findings may have important implications in regard to the role of PP2A as a tumor suppressor.

Closely related HIV-1 CRF01_AE variant among injecting drug users in northern Vietnam: evidence of HIV spread across the Vietnam-China border

To investigate the nature of recent HIV outbreaks among injecting drug users (IDUs) near the Vietnam-China border, we genetically analyzed 24 HIV-positive blood specimens from 2 northern provinces of Vietnam (Lang Son and quang Ninh) adjacent to the China border, where HIV outbreaks among IDUs were first detected in late 1996. Genetic subtyping based on gag (p17) and env (C2/V3) sequences revealed that CRF01_AE is a principal strain circulating throughout Vietnam, including the provinces near the China border. The majority of CRF01_AE sequences among IDUs in Quang Ninh and Lang Son showed significant clustering with those found in nearby Pingxiang City of China's Guangxi Province, sharing a unique valine substitution 12 amino acids downstream of the V3 loop. This particular subtype E variant, uniquely found among IDUs in northern Vietnam and southeastern China, is designated E(v). The genetic diversity of CRF01_AE distributed in Quang Ninh (1.5 +/- 0.6%) and Pingxiang City (1.9 +/- 1.2%) was remarkably low, indicating the emerging nature of HIV spread in these areas. It is also noted that the genetic diversity of CRF01_AE among IDUs was consistently lower than that in persons infected sexually, suggesting that fewer closely related CRF01_AE variants were introduced into IDUs and, conversely, that multiple strains of CRF01_AE had been introduced via the sexual route. The data in the present study provide additional evidence that HIV outbreaks among IDUs in northern Vietnam were caused by the recent introduction of a highly homogeneous CRF01_AE variant (E(v)) closely related to that prevailing in nearby southern China.

Disruption of protein phosphatase 2A subunit interaction in human cancers with mutations in the A alpha subunit gene

The A subunit of protein phosphatase 2A (PP2A) consists of 15 nonidentical repeats. The catalytic C subunit binds to C-terminal repeats 11 - 15 and regulatory B subunits bind to N-terminal repeats 1 - 10. Recently, four cancer-associated mutants of the A-alpha subunit have been described: Glu64-->Asp in lung carcinoma, Glu64-->Gly in breast carcinoma, Arg418-->Trp in melanoma, and Delta171 - 589 in breast carcinoma. Based on our model of PP2A, we predicted that Glu64-->Asp and Glu64-->Gly might be defective in B subunit binding, whereas Arg418-->Trp and Delta171 - 589 might bind neither B nor C subunits. We generated these mutants by site-directed mutagenesis and assayed their ability to associate with different forms of B subunits (B, B', B") or with the catalytic C subunit. The results demonstrate that all mutants are defective in binding either B or B and C subunits. Specifically, the N-terminal mutants, Glu64-->Asp and Glu64-->Gly, are defective in B' but normal in B, B", and C subunit binding, whereas the C-terminal mutants Arg418-->Trp and Delta171 - 589 bind none of the B subunits nor the C subunit. The implications of these findings with regard to the potential role of PP2A as a tumor suppressor are discussed. Oncogene (2001) 20, 10 - 15.

Urinary hyaluronic acid and hyaluronidase: markers for bladder cancer detection and evaluation of grade

PURPOSE

Specific patterns of progression and frequent recurrence of bladder tumors determine the choice of treatment, frequency of surveillance, quality of life, and ultimately, patient prognosis. The prognosis would be improved if an accurate noninvasive test was available for diagnosis. Identification of markers that function in bladder cancer progression would be helpful in designing such diagnostic tests. The glycosaminoglycan, hyaluronic acid (HA), promotes tumor metastasis. Hyaluronidase (HAase), an endoglycosidase, degrades HA into small fragments that promote angiogenesis. We have previously shown that both HA and HAase are associated with bladder cancer and may function in bladder tumor angiogenesis. In this study we examined whether urinary HA and HAase levels serve as bladder cancer markers.

MATERIALS AND METHODS

Among the 513 urine specimens analyzed, 261 were from transitional cell carcinoma (TCC) patients, 9 from patients with non-TCC tumors, and 243 from controls (normals, patients with other genitourinary (GU) conditions or a history of bladder cancer (HxBCa)). The urinary HA and HAase levels were measured by two ELISA-like assays that utilize a biotinylated HA binding protein for detection. These levels were normalized to total urinary protein and were expressed as ng./mg. (HA test) and mU/mg. (HAase test), respectively.

RESULTS

The urinary HA levels were elevated (2.5 to 6.5 fold) in bladder cancer patients (1173.7+/-173.4; n = 261) as compared with normals (246.1+/-38.5; n = 41); GU patients (306.6+/-32.2; n = 133), and patients with a HxBCa (351.1+/-49.1; n = 69) (p <0.001). The urinary HAase levels were elevated (3 to 7 fold) in G2/G3 bladder cancer patients (26.2+/-3.2) as compared with normals (4.5+/-0.9) and patients with either GU conditions (5.8+/-1.3), HxBCa (8.2+/-2.6) or G1 tumors (9.7+/-2.5) (p <0.001). The HA test showed 83.1% sensitivity, 90.1% specificity and 86.5% accuracy in detecting bladder cancer, regardless of the tumor grade. The HAase test showed 81.5% sensitivity, 83.8% specificity and 82.9% accuracy to detect G2/G3 patients. Combining the inferences of the HA and HAase tests (HA-HAase test) resulted in detection of bladder cancer, regardless of tumor grade and stage, with higher sensitivity (91.2%) and accuracy (88.3%), and comparable specificity (84.4%).

CONCLUSION

Our results show that the HA-HAase urine test is a noninvasive, highly sensitive and specific method for detecting bladder cancer and evaluating its grade.

Growth and energy metabolism in aerobic fed-batch cultures of Saccharomyces cerevisiae: simulation and model verification

A kinetic model of overflow metabolism in Saccharomyces cerevisiae was used for simulation of aerobic fed-batch cultivations. An inhibitory effect of ethanol on the maximum respiration of the yeast was observed in the experiments and included in the model. The model predicts respiration, biomass, and ethanol formation and the subsequent ethanol consumption, and was experimentally validated in fed-batch cultivations. Oscillating sugar feed with resulting oscillating carbon dioxide production did not influence the maximum respiration rate, which indicates that the pyruvate dehydrogenase complex is not involved as a bottleneck causing aerobic ethanol formation.

Changes in high-dose-rate tandem and ovoid applicator positions during treatment in an unfixed brachytherapy system

PURPOSE

To measure the change in applicator position during treatment in an unfixed high-dose-rate (HDR) brachytherapy system and to evaluate the effect of the shifts on dose calculations.

MATERIALS AND METHODS

Posttreatment localization radiographs were obtained for 47 HDR treatments (26 tandem and ovoid applicators, 21 ovoids-only applicators). The authors measured the change in applicator position relative to the patient's bone anatomy. Doses to the target and critical structures were calculated for posttreatment applicator positions for comparison.

RESULTS

Average displacements of the tandem and ovoid applicators in anteroposterior dimension were 5 and 4 mm for the tandem and ovoids, respectively. Anterior displacement occurred twice as often as posterior displacement. The average lateral and longitudinal shifts were less. Less displacement was observed with ovoids-only insertions. The largest displacement for ovoids-only applicators was 3 mm in the anteroposterior dimension. A high bladder dose difference (17.4%) for tandem and ovoid applications correlated with anterior shifts of the applicators.

CONCLUSION

Patient movement in an unfixed HDR brachytherapy system can displace the applicators, especially the tandem. Anterior shifts correlate with high bladder dose differences. Immobilization of the patient's hips and legs, as well as stabilization of applicators, would reduce these shifts.

The role of endothelial function on the foot. Microcirculation and wound healing in patients with diabetes

Wound healing is defective in patients with diabetes, which may be attributed to many factors. Our data indicate that impairment of the microcirculation is a major factor. Although the exact causes of microvascular impairment are not known, dysfunction of the endothelium has emerged over the last decade as the prominent abnormality related to vascular disease in diabetes. Further studies are required to clarify the causes of endothelial dysfunction and identify potential therapeutic interventions in the future.

High-risk superficial bladder cancer: intravesical therapy for T1 G3 transitional cell carcinoma of the urinary bladder

The ideal treatment for T1 G3 transitional cell carcinoma (TCC) of the urinary bladder remains controversial. Therapeutic options after the initial transurethral (TUR) resection are observation, intravesical therapy, a repeat resection, radiation therapy, and cystectomy. Because more than half of patients with T1 G3 TCC of the urinary bladder do not progress, initial cystectomy can represent overtreatment. However, observation alone following TUR for T1 G3 TCC of the urinary bladder is associated with a progression rate of 48%. Intravesical immunotherapy has been shown to decrease recurrence and progression in high-grade Ta carcinoma in situ and T1 bladder cancer. When patients with T1 G3 tumors are well selected, intravesical therapy following the initial TUR can significantly improve survival and quality of life. Persistence or recurrence of high-grade tumor mandates consideration of cystectomy.

Tumor-derived hyaluronidase: a diagnostic urine marker for high-grade bladder cancer

The detection of high-grade bladder tumors prior to invasion is crucial for a good prognosis. We recently found that the levels of hyaluronic acid (HA), a glycosaminoglycan, are elevated in the urine of bladder cancer patients, and small angiogenic HA fragments are present in the urine of high-grade bladder cancer patients. Hyaluronidase is an enzyme that degrades HA into small angiogenic fragments. We compared the urinary hyaluronidase levels of normal individuals and patients with bladder cancer or other genitourinary conditions, using a substrate (HA)-gel technique and an ELISA-like assay. Among the 139 specimens analyzed, the urinary hyaluronidase levels in patients with G2/G3 tumors (33.4 +/- 4.5 milliunits/mg protein) are 5-8-fold higher than those in normal individuals (4.2 +/- 1.2 milliunits/mg protein) and those in patients with G1 tumors (6.5 +/- 1.7 milliunits/mg protein) or other genitourinary conditions (7.4 +/- 1.4 milliunits/mg protein; P < 0.001). Urinary hyaluronidase measurement shows a sensitivity of 100% and a specificity of 88.8% to detect high-grade bladder (G2/G3) tumors. Thus urinary hyaluronidase measurement is a simple, noninvasive yet highly specific and sensitive method for high-grade bladder cancer detection. The increase in urinary hyaluronidase levels is due to the secretion of a tumor-associated hyaluronidase into the urine because the hyaluronidase levels in G2/G3 tumor tissues are also higher (6-7-fold) than those in normal bladder and G1 tumor tissues (P < 0.001). The bladder tumor-associated hyaluronidase activity is distinct from other hyaluronidases, has a pH optimum of 4.3, and is attributed to two proteins with molecular masses of 65 kD (p65) and 55 kD (p55).

Association of elevated levels of hyaluronidase, a matrix-degrading enzyme, with prostate cancer progression

Components of extracellular matrix and the matrix-degrading enzymes are some of the key regulators of tumor metastasis and angiogenesis. Hyaluronic acid (HA), a matrix glycosaminoglycan, is known to promote tumor cell adhesion and migration, and its small fragments are angiogenic. We have compared levels of hyaluronidase, an enzyme that degrades HA, in normal adult prostate (NAP), benign prostate hyperplasia (BPH) and prostate cancer (CaP) tissues and in conditioned media from epithelial explant cultures, using a sensitive substrate(HA)-gel assay and an ELISA-like assay. The results show a significant elevation (3-10-fold) of this enzyme in tumor tissues compared to that in NAP and BPH tissues. Furthermore, the hyaluronidase levels in tissues correlates well with the tumor grade. For example, the concentrations in a locally extended CaP lesion (191 +/- 7.9 milliunits/mg protein), and low-grade tumors (9.4 +/- 1.4 milliunits/mg protein), respectively. Among the primary epithelial explant cultures, CaP cultures secrete at least 10-fold higher levels of hyaluronidase that those secreted by NAP and BPH cultures. Furthermore, among the established prostate cancer cell lines, DU145, an androgen-unresponsive metastatic line, secretes 4-fold more hyaluronidase than LNCaP, an androgen-responsive and relatively well-differentiated cell line. We also show that prostatic hyaluronidase has an apparent M(r) approximate to 55,000, a pH optimum of 4.6, and is distinct from other well-characterized hyaluronidases.

Postoperative transient bradycardia and asystole after bilateral bunionectomies performed using spinal anesthesia

Medical complications after elective bunionectomy procedures are rarely encountered. This paper presents a case report of a healthy 51-year-old male patient who experienced transient bradycardia and asystole postoperatively after bilateral bunionectomies. The foot surgeon must be prepared for, be able to recognize, and then treat these untoward medical events.

[Leucocyte chemotaxis and its anomalies (author's transl)]

The chemotaxis of granular leucocytes was studied in vitro using three different methods : direct observation under the microscope, trans-membrane migration in a Boyden's chamber, and migration under agarose. Numerous factors were found to have chemotactic activity, the most potent being C5a a component of the serum complement activated by the classical or the alternative pathway. The origin of chemotaxis anomalies in infectious or inflammatory diseases were traced to cellular or seric disorders. The mechanisms primarily involved in chemotaxis are specific cell membrane receptors, the cytoskeleton and the cyclic nucleotides cAMP cGMP.

[Disturbances of chemotaxis in protein-calorie malnutrition (author's transl)]

A study of specific and non-specific immune functions was performed in 14 children presenting with severe malnutrition, before and after parenteral hyperalimentation by central catheter. Anomalies of cellular functions (reduction of the percentage of E rosettes and deficient proliferation with mitogens) were rarely found. Measurements for serum immunoglobulins did not show any anomaly; however reduced percentages of EAC rosettes and important increase in "null" cells were found in about one third of the cases. The main finding was a decreased serum chemotactic activity following activation of the classic complement pathway. This was found in 12 children and returned to normal values in all cases after hyperalimentation.