Establishment of patient-derived tumor organoids to functionally inform treatment decisions in metastatic colorectal cancer.

BACKGROUND: Metastatic colorectal cancer (mCRC) patients tend to have modest benefits from molecularly driven therapeutics. Patient-derived tumor organoids (PDTOs) represent an unmatched model to elucidate tumor resistance to therapy, due to their high capacity to resemble tumor characteristics. MATERIALS AND METHODS: We used viable tumor tissue from two cohorts of patients with mCRC, naïve or refractory to treatment, respectively, for generating PDTOs. The derived models were subjected to a 6-day drug screening assay (DSA) with a comprehensive pipeline of chemotherapy and targeted drugs against almost all the actionable mCRC molecular drivers. For the second cohort DSA data were matched with those from PDTO genotyping. RESULTS: A total of 40 PDTOs included in the two cohorts were derived from mCRC primary tumors or metastases. The first cohort included 31 PDTOs derived from patients treated in front line. For this cohort, DSA results were matched with patient responses. Moreover, RAS/BRAF mutational status was matched with DSA cetuximab response. Ten out of 12 (83.3%) RAS wild-type PDTOs responded to cetuximab, while all the mutant PDTOs, 8 out of 8 (100%), were resistant. For the second cohort (chemorefractory patients), we used part of tumor tissue for genotyping. Four out of nine DSA/genotyping data resulted applicable in the clinic. Two RAS-mutant mCRC patients have been treated with FOLFOX-bevacizumab and mitomycin-capecitabine in third line, respectively, based on DSA results, obtaining disease control. One patient was treated with nivolumab-second mitochondrial-derived activator of caspases mimetic (phase I trial) due to high tumor mutational burden at genotyping, experiencing stable disease. In one case, the presence of BRCA2 mutation correlated with DSA sensitivity to olaparib; however, the patient could not receive the therapy. CONCLUSIONS: Using CRC as a model, we have designed and validated a clinically applicable methodology to potentially inform clinical decisions with functional data. Undoubtedly, further larger analyses are needed to improve methodology success rates and propose suitable treatment strategies for mCRC patients.

Older adults benefit from more widespread brain network integration during working memory.

Neuroimaging evidence suggests that the aging brain relies on a more distributed set of cortical regions than younger adults in order to maintain successful levels of performance during demanding cognitive tasks. However, it remains unclear how task demands give rise to this age-related expansion in cortical networks. To investigate this issue, functional magnetic resonance imaging was used to measure univariate activity, network connectivity, and cognitive performance in younger and older adults during a working memory (WM) task. Here, individuals performed a WM task in which they held letters online while reordering them alphabetically. WM load was titrated to obtain four individualized difficulty levels with different set sizes. Network integration-defined as the ratio of within-versus between-network connectivity-was linked to individual differences in WM capacity. The study yielded three main findings. First, as task difficulty increased, network integration decreased in younger adults, whereas it increased in older adults. Second, age-related increases in network integration were driven by increases in right hemisphere connectivity to both left and right cortical regions, a finding that helps to reconcile existing theories of compensatory recruitment in aging. Lastly, older adults with higher WM capacity demonstrated higher levels of network integration in the most difficult task condition. These results shed light on the mechanisms of age-related network reorganization by demonstrating that changes in network connectivity may act as an adaptive form of compensation, with older adults recruiting a more distributed cortical network as task demands increase.

Online repetitive transcranial magnetic stimulation during working memory in younger and older adults: A randomized within-subject comparison.

Working memory is the ability to perform mental operations on information that is stored in a flexible, limited capacity buffer. The ability to manipulate information in working memory is central to many aspects of human cognition, but also declines with healthy aging. Given the profound importance of such working memory manipulation abilities, there is a concerted effort towards developing approaches to improve them. The current study tested the capacity to enhance working memory manipulation with online repetitive transcranial magnetic stimulation in healthy young and older adults. Online high frequency (5Hz) repetitive transcranial magnetic stimulation was applied over the left dorsolateral prefrontal cortex to test the hypothesis that active repetitive transcranial magnetic stimulation would lead to significant improvements in memory recall accuracy compared to sham stimulation, and that these effects would be most pronounced in working memory manipulation conditions with the highest cognitive demand in both young and older adults. Repetitive transcranial magnetic stimulation was applied while participants were performing a delayed response alphabetization task with three individually-titrated levels of difficulty. The left dorsolateral prefrontal cortex was identified by combining electric field modeling to individualized functional magnetic resonance imaging activation maps and was targeted during the experiment using stereotactic neuronavigation with real-time robotic guidance, allowing optimal coil placement during the stimulation. As no accuracy differences were found between young and older adults, the results from both groups were collapsed. Subsequent analyses revealed that active stimulation significantly increased accuracy relative to sham stimulation, but only for the hardest condition. These results point towards further investigation of repetitive transcranial magnetic stimulation for memory enhancement focusing on high difficulty conditions as those most likely to exhibit benefits.

Dual MET and ERBB inhibition overcomes intratumor plasticity in osimertinib-resistant-advanced non-small-cell lung cancer (NSCLC).

BACKGROUND: Third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) such as osimertinib are the last line of targeted treatment of metastatic non-small-cell lung cancer (NSCLC) EGFR-mutant harboring T790M. Different mechanisms of acquired resistance to third-generation EGFR-TKIs have been proposed. It is therefore crucial to identify new and effective strategies to overcome successive acquired mechanisms of resistance. METHODS: For Amplicon-seq analysis, samples from the index patient (primary and metastasis lesions at different timepoints) as well as the patient-derived orthotopic xenograft tumors corresponding to the different treatment arms were used. All samples were formalin-fixed paraffin-embedded, selected and evaluated by a pathologist. For droplet digital PCR, 20 patients diagnosed with NSCLC at baseline or progression to different lines of TKI therapies were selected. Formalin-fixed paraffin-embedded blocks corresponding to either primary tumor or metastasis specimens were used for analysis. For single-cell analysis, orthotopically grown metastases were dissected from the brain of an athymic nu/nu mouse and cryopreserved at -80°C. RESULTS: In a brain metastasis lesion from a NSCLC patient presenting an EGFR T790M mutation, we detected MET gene amplification after prolonged treatment with osimertinib. Importantly, the combination of capmatinib (c-MET inhibitor) and afatinib (ErbB-1/2/4 inhibitor) completely suppressed tumor growth in mice orthotopically injected with cells derived from this brain metastasis. In those mice treated with capmatinib or afatinib as monotherapy, we observed the emergence of KRAS G12C clones. Single-cell gene expression analyses also revealed intratumor heterogeneity, indicating the presence of a KRAS-driven subclone. We also detected low-frequent KRAS G12C alleles in patients treated with various EGFR-TKIs. CONCLUSION: Acquired resistance to subsequent EGFR-TKI treatment lines in EGFR-mutant lung cancer patients may induce genetic plasticity. We assess the biological insights of tumor heterogeneity in an osimertinib-resistant tumor with acquired MET-amplification and propose new treatment strategies in this situation.

Candida meningitis in an immunocompetent patient detected through (1→3)-beta-d-glucan.

A 44-year-old female presented with a 3-month history of headache, dizziness, nausea, and vomiting. Her past medical history was significant for long-standing intravenous drug abuse. Shortly after admission, the patient became hypertensive and febrile, with fever as high as 38.8°C. The lumbar puncture profile supported an infectious process; however multiple cultures of blood and cerebrospinal fluid (CSF) did not initially show growth of organisms. Finally after 9 days of incubation, a CSF culture showed evidence of a few colonies of Candida albicans. To confirm the diagnosis, preserved CSF from that sample was tested for (1→3)-ß-d-glucan, showing levels >500pg/ml. This report illustrates a rare complication of intravenous drug use in an immunocompetent patient and demonstrates the utility of (1→3)-ß-d-glucan testing in possible Candida meningitis.

BRG1/SMARCA4 is essential for neuroblastoma cell viability through modulation of cell death and survival pathways.

Neuroblastoma (NB) is a neoplasm of the sympathetic nervous system, and is the most common solid tumor of infancy. NBs are very heterogeneous, with a clinical course ranging from spontaneous regression to resistance to all current forms of treatment. High-risk patients need intense chemotherapy, and only 30-40% will be cured. Relapsed or metastatic tumors acquire multi-drug resistance, raising the need for alternative treatments. Owing to the diverse mechanisms that are responsible of NB chemoresistance, we aimed to target epigenetic factors that control multiple pathways to bypass therapy resistance. We found that the SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a, member 4 (SMARCA4/BRG1) was consistently upregulated in advanced stages of NB, with high BRG1 levels being indicative of poor outcome. Loss-of-function experiments in vitro and in vivo showed that BRG1 is essential for the proliferation of NB cells. Furthermore, whole-genome transcriptome analysis revealed that BRG1 controls the expression of key elements of oncogenic pathways such as PI3K/AKT and BCL2, which offers a promising new combination therapy for high-risk NB.

SPROUTY-2 represses the epithelial phenotype of colon carcinoma cells via upregulation of ZEB1 mediated by ETS1 and miR-200/miR-150.

SPROUTY-2 (SPRY2) is a modulator of tyrosine kinase receptor signaling with receptor- and cell type-dependent inhibitory or enhancing effects. Studies on the action of SPRY2 in major cancers are conflicting and its role remains unclear. Here we have dissected SPRY2 action in human colon cancer. Global transcriptomic analyses show that SPRY2 downregulates genes encoding tight junction proteins such as claudin-7 and occludin and other cell-to-cell and cell-to-matrix adhesion molecules in human SW480-ADH colon carcinoma cells. Moreover, SPRY2 represses LLGL2/HUGL2, PATJ1/INADL and ST14, main regulators of the polarized epithelial phenotype, and ESRP1, an epithelial-to-mesenchymal transition (EMT) inhibitor. A key action of SPRY2 is the upregulation of the major EMT inducer ZEB1, as these effects are reversed by ZEB1 knock-down by means of RNA interference. Consistently, we found an inverse correlation between the expression level of claudin-7 and those of SPRY2 and ZEB1 in human colon tumors. Mechanistically, ZEB1 upregulation by SPRY2 results from the combined induction of ETS1 transcription factor and the repression of microRNAs (miR-200 family, miR-150) that target ZEB1 RNA. Moreover, SPRY2 increased AKT activation by epidermal growth factor, whereas AKT and also Src inhibition reduced the induction of ZEB1. Altogether, these data suggest that AKT and Src are implicated in SPRY2 action. Collectively, these results show a tumorigenic role of SPRY2 in colon cancer that is based on the dysregulation of tight junction and epithelial polarity master genes via upregulation of ZEB1. The dissection of the mechanism of action of SPRY2 in colon cancer cells is important to understand the upregulation of this gene in a subset of patients with this neoplasia that have poor prognosis.

SPROUTY2 is a ß-catenin and FOXO3a target gene indicative of poor prognosis in colon cancer.

SPROUTY2 (SPRY2) is an intracellular regulator of receptor tyrosine kinase signaling involved in cell growth, differentiation and tumorigenesis. Here, we show that SPRY2 is a target gene of the Wnt/ß-catenin pathway that is abnormally activated in more than 90% of colon carcinomas. In human colon cancer cells, SPRY2 expression is induced by ß-catenin in co-operation with the transcription factor FOXO3a instead of lymphoid enhancer factor/T-cell factor proteins. We found binding of ß-catenin to the SPRY2 promoter at FOXO3a response elements. In vivo, cells marked by nuclear ß-catenin and FOXO3a express SPRY2 in proliferative epithelial tissues, such as intestinal mucosa and epidermis. Consistently, inducible ß-catenin deletion in mice reduced Spry2 expression in the small intestine. Moreover, SPRY2 protein expression correlated with nuclear ß-catenin and FOXO3a colocalization in human colon carcinomas. Importantly, the amount of SPRY2 protein correlated with shorter overall survival of colon cancer patients. Our data reveal SPRY2 as a novel Wnt/ß-catenin and FOXO3a target gene indicative of poor prognosis in colon cancer.

Computed tomographic anatomy of the nasal cavity, paranasal sinuses and tympanic cavity of the koala.

OBJECTIVE: To use cross-sectional imaging (helical computed tomography (CT)) combined with conventional anatomical dissection to define the normal anatomy of the nasal cavity and bony cavitations of the koala skull. METHODS: Helical CT scans of the heads of nine adult animals were obtained using a multislice scanner acquiring thin slices reconstructed in the transverse, sagittal and dorsal planes. Subsequent anatomical dissection permitted confirmation of correct identification and further delineation of bony and air-filled structures visible in axial and multiplanar reformatted CT images. RESULTS: The nasal cavity was relatively simple, with little scrolling of nasal conchae, but bony cavitations were complex and extensive. A rostral maxillary recess and ventral conchal, caudal maxillary, frontal and sphenoidal paranasal sinuses were identified and characterised. Extensive temporal bone cavitation was shown to be related to a large epitympanic recess. CONCLUSIONS: The detailed anatomical data provided are applicable to future functional and comparative anatomical studies, as well as providing a preliminary atlas for clinical investigation of conditions such as cryptococcal rhinosinusitis, a condition more common in the koala than in many other species.

Assessment of treatment patterns and patient outcomes before vs after implementation of a severity-based Clostridium difficile infection treatment policy.

BACKGROUND: National guidelines recommend oral vancomycin for severe Clostridium difficile infection (CDI) based on results from recent clinical trials demonstrating improved clinical outcomes. However, real-world data to support these clinical trials are scant. AIM: To compare treatment patterns and patient outcomes of those treated for CDI before and after implementation of a severity-based CDI treatment policy at a tertiary teaching hospital. METHODS: This study evaluated adult patients with a positive C. difficile toxin before and after implementation of a policy where patients with severe CDI given metronidazole were switched to oral vancomycin unless contra-indicated. Patients were stratified according to disease severity using a modified published severity score. Treatment patterns based on CDI severity and rates of refractory CDI were assessed. FINDINGS: In total, 256 patients with CDI (mean age 66 years, standard deviation 17, 52% female) were evaluated (before implementation: N = 144; after implementation: N = 112). Use of oral vancomycin for severe CDI increased significantly from 14% (N = 8) to 91% (N = 48) following implementation of the policy (P < 0.0001). Refractory disease in patients with severe CDI decreased significantly from 37% to 15% following implementation of the policy (P = 0.035). No significant differences were noted among patients with mild to moderate CDI. CONCLUSION: A severity-based CDI treatment policy at a tertiary teaching hospital increased the use of oral vancomycin and was associated with decreased rates of refractory CDI.

Structural brain changes after 4 wk of unilateral strength training of the lower limb.

Strength training enhances muscular strength and neural drive, but the underlying neuronal mechanisms remain unclear. This study used magnetic resonance imaging (MRI) to identify possible changes in corticospinal tract (CST) microstructure, cortical activation, and subcortical structure volumes following unilateral strength training of the plantar flexors. Mechanisms underlying cross-education of strength in the untrained leg were also investigated. Young, healthy adult volunteers were assigned to training (n = 12) or control (n = 9) groups. The 4 wk of training consisted of 16 sessions of 36 unilateral isometric plantar flexions. Maximum voluntary isometric contraction torque was tested pre- and posttraining. MRI investigation included a T1-weighted scan, diffusion tensor imaging and functional MRI. Probabilistic fiber tracking of the CST was performed on the diffusion tensor imaging images using a two-regions-of-interest approach. Fractional anisotropy and mean diffusivity were calculated for the left and right CST in each individual before and after training. Standard functional MRI analyses and volumetric analyses of subcortical structures were also performed. Maximum voluntary isometric contraction significantly increased in both the trained and untrained legs of the training group, but not the control group. A significant decrease in mean diffusivity was found in the left CST following strength training of the right leg. No significant changes were detected in the right CST. No significant changes in cortical activation were observed following training. A significant reduction in left putamen volume was found after training. This study provides the first evidence for strength training-related changes in white matter and putamen in the healthy adult brain.

Clinical and microbiological implications of time-to-positivity of blood cultures in patients with Gram-negative bacilli bacteremia.

Time-to-positivity (TTP) is defined as the length of time from the beginning of culture incubation to the detection of bacterial growth by an automated system. The objective of this study was to assess the clinical and microbiological implications of TTP among patients with Gram-negative bacilli (GNB) bacteremia. This was a prospective, single-center, observational study. Patients aged 18 years or older with one or more blood cultures growing GNB were included and followed until hospital discharge or death. Patients were excluded if they were without symptoms of infection, if they had polymicrobial culture, or if the culture was positive with an obligate anaerobe. A multivariate logistic regression analysis was performed to determine the predictors of in-hospital mortality, including TTP (primary endpoint), demographics, disease severity, comorbidities, pathogen type, source of infection, time to symptom resolution, hospital/intensive care unit (ICU) length of stay, adequacy of empiric antibiotics, and presence of an extended-spectrum beta-lactamase (ESBL)-producing bacteria. One hundred consecutive patients with GNB bacteremia were enrolled. TTP was an independent predictor of mortality; for every hour that TTP was shorter, the risk of mortality increased by 10% [odds ratio (OR) 1.10, 95% confidence interval (CI) 1.00-1.21, p = 0.049]. Other predictors of mortality included severity of illness, ESBL-producing GNB, and ICU admission within 24 h before culture. Mortality was highest among patients with inadequate empiric therapy (56% vs. 14%, p < 0.001) and TTP <11 h (23.1% vs. 8.3%, p = 0.18). Lactose-fermenting GNB had a shorter mean TTP than non-lactose fermenters (11.4 vs. 17.9 h, p = 0.001). Among patients with bacteremia due to GNB, TTP values are inversely associated with mortality risk.

Impact of a Multimodal Antimicrobial Stewardship Program on Pseudomonas aeruginosa Susceptibility and Antimicrobial Use in the Intensive Care Unit Setting.

Objective. To study the impact of our multimodal antibiotic stewardship program on Pseudomonas aeruginosa susceptibility and antibiotic use in the intensive care unit (ICU) setting. Methods. Our stewardship program employed the key tenants of published antimicrobial stewardship guidelines. These included prospective audits with intervention and feedback, formulary restriction with preauthorization, educational conferences, guidelines for use, antimicrobial cycling, and de-escalation of therapy. ICU antibiotic use was measured and expressed as defined daily doses (DDD) per 1,000 patient-days. Results. Certain temporal relationships between antibiotic use and ICU resistance patterns appeared to be affected by our antibiotic stewardship program. In particular, the ICU use of intravenous ciprofloxacin and ceftazidime declined from 148 and 62.5 DDD/1,000 patient-days to 40.0 and 24.5, respectively, during 2004 to 2007. An increase in the use of these agents and resistance to these agents was witnessed during 2008-2010. Despite variability in antibiotic usage from the stewardship efforts, we were overall unable to show statistical relationships with P. aeruginosa resistance rate. Conclusion. Antibiotic resistance in the ICU setting is complex. Multimodal stewardship efforts attempt to prevent resistance, but such programs clearly have their limits.

Evaluation of antifungal therapy in patients with candidaemia based on susceptibility testing results: implications for antimicrobial stewardship programmes.

BACKGROUND: Definitive antifungal therapy is typically based on Candida species and clinical status, rather than susceptibility reports. Antifungal susceptibility testing is available, but the impact on treatment decisions is unknown. The purpose of this study was to assess antifungal therapy in hospitalized patients with candidaemia during the time period between the start of empirical therapy and after antifungal susceptibility testing reports are available. METHODS: A retrospective study of 161 hospitalized patients with candidaemia was conducted. Patients who received fluconazole or an echinocandin were evaluated for changes in empirical antifungal therapy prior to and after susceptibility reporting. RESULTS: One hundred and sixty-one patients aged 59 ±â€Š16 years (male, 54%; Caucasian, 52%; APACHE II score ≥ 15, 48%; and intensive care unit, 50%) were identified, of whom 130 (81%) had fluconazole-susceptible candidaemia. Fifty-eight patients (36%) were initiated on fluconazole and 103 (64%) on an echinocandin. The mean time from culture to the susceptibility report was 5 ±â€Š2 days. Prior to availability of the susceptibility report, 20 fluconazole-initiated patients (34%) were switched to an echinocandin, while 14 echinocandin-initiated patients (14%) were switched to fluconazole. Once a susceptibility report was available, 35 of 89 (39%) patients with fluconazole-susceptible candidaemia on an echinocandin were de-escalated to fluconazole. Eleven patients on fluconazole just prior to a susceptibility report were identified with a fluconazole-resistant Candida species. CONCLUSIONS: Using antifungal susceptibility testing, patients given fluconazole with fluconazole-resistant Candida species were identified. Less than 40% of echinocandin-treated patients with fluconazole-susceptible organisms were de-escalated to fluconazole. Antifungal susceptibility testing may help to identify patients in need of clinical intervention.

SPROUTY-2 and E-cadherin regulate reciprocally and dictate colon cancer cell tumourigenicity.

SPROUTY-2 (SPRY2) regulates receptor tyrosine kinase signalling and therefore cell growth and differentiation. In this study, we show that SPRY2 expression in colon cancer cells is inhibited by the active vitamin D metabolite 1alpha,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) through E-cadherin-dependent and -independent mechanisms. In turn, SPRY2 represses both basal and 1,25(OH)(2)D(3)-induced E-cadherin expression. In line with this, SPRY2 induces ZEB1 RNA and protein, but not that of other epithelial-to-mesenchymal transition inducers that repress the CDH1/E-cadherin promoter. Consistently, SPRY2 and E-cadherin protein levels inversely correlate in colon cancer cell lines and xenografted tumours. Moreover, SPRY2 knockdown by small hairpin RNA increases CDH1/E-cadherin expression and, reciprocally, CDH1/E-cadherin knockdown increases that of SPRY2. In colon cancer patients, SPRY2 is upregulated in undifferentiated high-grade tumours and at the invasive front of low-grade carcinomas. Quantification of protein expression in 34 tumours confirmed an inverse correlation between SPRY2 and E-cadherin. Our data demonstrate a tumourigenic action of SPRY2 that is based on the repression of E-cadherin, probably by the induction of ZEB1, and a reciprocal regulation of SPRY2 and E-cadherin that dictates cell phenotype. We propose SPRY2 as a candidate novel marker for high-grade tumours and a target of therapeutic intervention in colon cancer.

Increased urinary free immunoglobulin light chain excretion in patients with multiple sclerosis.

BACKGROUND: Plasma and B cells are implicated in multiple sclerosis (MS) and produce free light chains (FLC) that are excreted in urine. OBJECTIVE: To confirm that demyelinating diseases (DD) cause increased urinary FLCs. METHOD: Urinary FLC in 50 patients with DD were compared to 20 patients with posterior uveitis (PU), 19 with AIDS, 34 with rheumatoid arthritis (RA) and 19 normal controls (NC). RESULT: Subjects with DD, PU, RA and AIDS have higher urinary FLCs than NC (p<0.01). Urinary FLCs did not correlate with gadolinium-enhancing lesions on MRI. CONCLUSIONS: Urinary FLCs are raised in DD. Further studies are required to see if they correlate with disease activity.

Characteristics of patients infected with common Neisseria gonorrhoeae NG-MAST sequence type strains presenting at the Edinburgh genitourinary medicine clinic.

OBJECTIVE: Characterisation of population groups infected with common Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST) sequence types, presenting at the Edinburgh genitourinary medicine clinic. METHODS: All patients with gonococcal infection attending over a 2-year period were reviewed. Patients infected with unique, paired and clustered gonococcal sequence types were compared. The characteristics of patients infected with common sequence types were analysed. The concordance of gonococcal strains between sexual partners was examined. RESULTS: There were 78 unique, 17 paired and 34 clustered sequence types: the three groups varied significantly in relation to patient gender and origin/location of recent sexual contacts. There were nine large sequence type clusters (containing 11-24 isolates each) and these varied in terms of patient gender, sexual orientation and HIV prevalence. There was high concordance (94%) of sequence types between sexual contacts. CONCLUSION: There was a trend towards significance when comparing the risks of carriage/contact with HIV between different sequence type clusters. Further research is therefore warranted to determine if NG-MAST data can be used to help identify high-risk sexual networks.

Safety assessment of Lactobacillus brevis KB290 as a probiotic strain.

Lactobacillus brevis KB290 (KB290), a plant-derived probiotic lactic acid bacterium, reportedly improves gut health and stimulates immune function. Here we extensively investigated the geno-, acute, subacute, and subchronic toxicity of KB290 and its bacterial translocation potential. KB290 was non-mutagenic in the bacterial reverse mutation assay by the preincubation method. In the single oral dose toxicity test, KB290 at 10(9) cfu/ml was nontoxic at maximum capacity (20 ml/kg). When 10(8), 10(9), or 10(10) cfu/kg was administered daily to rats by gavage for 2 weeks (subacute assay), we observed no clear treatment-related effect and no evidence of bacterial translocation from the gastrointestinal tract. When it was administered for 13 weeks (subchronic assay), we again observed no clear treatment-related effect and no significant toxicological effect. Based on those results, we consider 10(10) cfu/kg per day, the highest dose tested, to be the no observed adverse effect level (NOAEL). These results suggest that KB290 is safe for human consumption.

Molecular epidemiology of syphilis in Scotland.

OBJECTIVE: To examine the molecular epidemiology of syphilis in Scotland. METHODS: Ulcer specimens were collected from 85 patients with infectious syphilis. Typing of Treponema pallidum was performed using a method that examines variation in two loci; the number of 60-basepair repeats within the arp gene and sequence variation in the tpr genes. RESULTS: Patients were predominately white men who have sex with men (MSM). Treponemal DNA was detected in 75 specimens and a total of six subtypes were identified from 58 typeable specimens (77%). The most common subtypes were 14d (44/58, 76%), followed by 14e (7/58, 12%), 14j (3/58, 5%), 14b (2/58, 3%), 14p and 14k (1/58, 2%). CONCLUSIONS: This study shows that subtype 14d is the predominant subtype circulating in Scotland and there is a surprising level of genetic diversity within the Scottish MSM community.