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Background: Mechanistic models, when combined with pertinent data, can improve our knowledge regarding important molecular and cellular mechanisms found in cancer. These models make the prediction of tissue-level response to drug treatment possible, which can lead to new therapies and improved patient outcomes. Here we present a data-driven multiscale modeling framework to study molecular interactions between cancer, stromal, and immune cells found in the tumor microenvironment. We also develop methods to use molecular data available in The Cancer Genome Atlas to generate sample-specific models of cancer., Results: By combining published models of different cells relevant to pancreatic ductal adenocarcinoma (PDAC), we built an agent-based model of the multicellular pancreatic tumor microenvironment, formally describing cell type-specific molecular interactions and cytokine-mediated cell-cell communications. We used an ensemble-based modeling approach to systematically explore how variations in the tumor microenvironment affect the viability of cancer cells. The results suggest that the autocrine loop involving EGF signaling is a key interaction modulator between pancreatic cancer and stellate cells. EGF is also found to be associated with previously described subtypes of PDAC. Moreover, the model allows a systematic exploration of the effect of possible therapeutic perturbations; our simulations suggest that reducing bFGF secretion by stellate cells will have, on average, a positive impact on cancer apoptosis., Conclusions: The developed framework allows model-driven hypotheses to be generated regarding therapeutically relevant PDAC states with potential molecular and cellular drivers indicating specific intervention strategies., (© The Author(s) 2020. Published by Oxford University Press.)

Background: Gestational diabetes mellitus (GDM) is associated with a sevenfold increased lifetime risk of type 2 diabetes. Excessive gestational weight gain and postpartum weight retention are established predictors of long-term obesity., Objective: To determine the impact of a postnatal lifestyle intervention program for overweight women with previous gestational diabetes mellitus (PAIGE)., Design: Postnatal overweight women with previous GDM participated in a multicenter randomized controlled trial between June 2013 and December 2014. The intervention comprised a 1-hour educational program, a free 3-month referral to a commercial weight management organization (Slimming World), a pedometer, and structured telephone and text support, in addition to usual care. The control group received usual care only. The primary outcome was weight loss at 6 months., Results: Sixty women were randomized (29 intervention; 31 control) in two centers based on their week of attendance. The intervention group demonstrated significant weight loss at 6 months after randomization compared with the control group: mean ±SD, 3.9 ± 7.0 kg vs 0.7 ±3.8 kg (P = 0.02). Blood glucose levels did not significantly differ. With respect to well-being measures, a bodily pain was significantly reduced in the intervention group (P = 0.007)., Conclusions: PAIGE resulted in significantly greater weight loss at 6 months compared with usual care. Such weight loss could prove beneficial in terms of better long-term health and subsequent prevention of type 2 diabetes in overweight women with previous GDM. Future interventions must consider recruitment strategies, timing of the intervention, and inclusion of partners and/or other family members.

Objectives: To investigate the molecular epidemiology, antimicrobial susceptibility and carbapenem resistance determinants of Acinetobacter baumannii isolates from respiratory tract samples of patients diagnosed with ventilator-associated pneumonia (VAP) who were enrolled in the MagicBullet clinical trial., Methods: A. baumannii isolates were prospectively cultured from respiratory tract samples from 65 patients from 15 hospitals in Greece, Italy and Spain. Susceptibility testing was performed by broth microdilution. Carbapenem resistance determinants were identified by PCR and sequencing. Molecular epidemiology was investigated using rep-PCR (DiversiLab) and international clones (IC) were identified using our in-house database., Results: Of 65 isolates, all but two isolates (97%) were resistant to imipenem and these were always associated with an acquired carbapenemase, OXA-23 (80%), OXA-40 (4.6%), OXA-58 (1.5%) or OXA-23/58 (1.5%). Resistance to colistin was 47.7%. Twenty-two isolates were XDR, and 20 isolates were pandrug-resistant (PDR). The majority of isolates clustered with IC2 (n = 54) with one major subtype comprising isolates from 12 hospitals in the three countries, which included 19 XDR and 16 PDR isolates., Conclusions: Carbapenem resistance rates were very high in A. baumannii recovered from patients with VAP. Almost half of the isolates were colistin resistant, and 42 (64.6%) isolates were XDR or PDR. Rep-PCR confirmed IC2 is the predominant clonal lineage in Europe and suggests the presence of an epidemic XDR/PDR A. baumannii clone that has spread in Greece, Italy and Spain. These data highlight the difficulty in empirical treatment of patients with A. baumannii VAP in centres with a high prevalence of carbapenem-resistant A. baumannii., (© The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.)

Objectives: The objective of this study was to determine the prevalence and correlates of pretreatment drug resistance (PDR) to first-line antiretroviral drugs among people initiating therapy for HIV in Vietnam., Methods: Blood was collected during November 2009 to October 2010 from people consecutively initiating ART in four purposively selected public outpatient clinics in three Vietnamese cities. At each study site, recruitment lasted for 6-10 months until the target sample size (range 120-130 individuals) had been reached. The viral load was measured in 501 samples; 490 samples (viral load ≥1000 copies/mL) were genotyped using a nucleotide population-based sequencing assay. Self-reported demographic and clinical data were elicited through interviews. We classified drug-resistance-associated mutations (DRMs) according to the 2009 WHO surveillance list., Results: DRMs were identified in 17/490 participants (3.5%; 95% CI 2.2%-5.5%). The prevalence of DRMs was 1.6% (8/490) against NRTIs, 1.6% (8/490) against NNRTIs and 0.8% (4/490) against PIs; three (0.6%) participants were resistant to both NRTIs and NNRTIs. The overall prevalence of PDR to first-line drugs was low [2.7% (13/490); 95% CI 1.6%-4.4%]. The prevalence of PDR to first-line drugs was greater among 198 HIV-infected participants who injected drugs than among 286 participants who reported risks for sexually acquired HIV (4.0% versus 1.4%, P = 0.079). Multivariable logistic regression analysis suggested that PDR to first-line drugs was significantly higher among people who injected drugs (OR = 3.94; 95% CI 1.13-13.68)., Conclusions: With low PDR, first-line ART may be effective in Vietnam and pretreatment genotyping may be unnecessary. Continuing strategies for the prevention and surveillance of antiretroviral resistance are important for maintaining a low prevalence of antiretroviral resistance in Vietnam. The association between resistance and injection drug use warrants further research., (© The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: GB virus C (GBV-C) is an apathogenic virus that inhibits human immunodeficiency virus (HIV) replication in vitro. Mother-to-child transmission (MTCT) of GBV-C has been observed in multiple small studies. Our study examined the rate and correlates of MTCT of GBV-C in a large cohort of GBV-C-HIV-coinfected pregnant women in Thailand., Methods: Maternal delivery plasma specimens from 245 GBV-C-HIV-infected women and specimens from their infants at 4 or 6 months of age were tested for GBV-C RNA. Associations with MTCT of GBV-C were examined using logistic regression., Results: One hundred one (41%) of 245 infants acquired GBV-C infection. MTCT of GBV-C was independently associated with maternal antiretroviral therapy (adjusted odds ratio [AOR], 5.21 [95% confidence interval {CI}, 2.12-12.81]), infant HIV infection (AOR, 0.05 [95% CI, 0.01-0.26]), maternal GBV-C load (8.0 log(10) copies/mL: AOR, 86.77 [95% CI, 15.27-481.70]; 7.0-7.9 log(10) copies/mL: AOR, 45.62 [95% CI, 8.41-247.51]; 5.0-6.9 log(10) copies/mL: AOR, 9.07 [95% CI, 1.85-44.33]: reference, <5 log(10) viral copies/mL), and caesarean delivery (AOR, 0.26 [95% CI, 0.12-0.59])., Conclusions: Associations with maternal GBV-C load and mode of delivery suggest transmission during pregnancy and delivery. Despite mode of delivery being a common risk factor for virus transmission, GBV-C and HIV were rarely cotransmitted. The mechanisms by which maternal receipt of antiretroviral therapy might increase MTCT of GBV-C are unknown.

Conventional surgery and radiotherapy for acromegaly have limitations. There are few data on the use of the somatostatin analog octreotide (Oct) as primary medical therapy. An open prospective study of 27 patients with newly diagnosed acromegaly was conducted in nine endocrine centers in the United Kingdom. Twenty patients had macroadenomas, and 7 had microadenomas. For the first 24 wk (phase 1), patients received sc Oct in an initial dose of 100 microg, 3 times daily, increased to 200 micro g three times daily after 4 wk in the 13 patients whose mean serum GH remained greater than 5 mU/liter (2 microg/liter). Five-point GH profiles were performed at 0, 4, 12, and 24 wk, and high resolution pituitary imaging using a standard protocol was performed at 0, 12, and 24 wk (magnetic resonance imaging in 25 patients and computed tomography in 2). Tumor dimensions and volumes were calculated by a central, reporting neuroradiologist, and the results were audited by a second, independent neuroradiologist. After 24 wk, 15 patients proceeded to phase 2 of the study with a direct switch to monthly injections of the depot formulation of Oct, Sandostatin long-acting release (Oct-LAR). Further GH profiles were performed at 36 and 48 wk, and pituitary imaging was performed at 48 wk. The median pretreatment serum GH concentration was 30.7 mU/liter (range, 6.7-141.4). During sc Oct, serum GH fell to less than 5 mU/liter in 9 patients (38%), and IGF-I fell to normal in 8 patients (33%). All 27 tumors shrank during sc Oct; for microadenomas the median tumor volume reduction was 49% (range, 12-73), and for macroadenomas it was 43% (range, 6-92). After 24 wk of Oct-LAR (end of phase 2), the GH level was less than 5 mU/liter in 11 of 14 patients (79%), and IGF-I was normal in 8 of 15 patients (53%). In the 15 patients given Oct-LAR (10 macroadenomas), wk 48 scans showed a further overall median tumor volume reduction of 24%. At the end of the study 79% of patients had mean serum GH levels below 5 mU/liter, 53% had normal IGF-I levels, and 73% showed greater than 30% tumor shrinkage. Twenty-nine percent of patients achieved all 3 targets, but no patient with pretreatment GH levels above 50 mU/liter did so at any stage of the study. Primary medical therapy with Oct offers the prospect of normalization of GH/IGF-I levels together with substantial tumor shrinkage in a significant subset of acromegalic patients. This is most likely to occur in patients with pretreatment GH levels less than 50 mU/liter (20 microg/liter).

Defined regions of the rfb gene cluster of Group E1 Salmonella enterica serovar Anatum were introduced into a mutated derivative of this strain that lacks O-polysaccharide polymerase activity. Three different kinds of assays performed on the various transformants all indicate that two functional wzy (rfc) genes reside within the Group E1 Salmonella rfb gene cluster. The product of ORF9.6, positioned near the center of the rfb gene cluster, joins O-polysaccharide repeat units together by alpha-glycosidic linkages to produce antigen O10, the major serological determinant of Group E1 S. enterica. The product of ORF17.4, positioned at the downstream end of the rfb gene cluster, can join repeat units together by beta-glycosidic linkages to produce antigen O15, the major serological determinant of Group E2 S. enterica.

Background: Heavy proteinuria is associated with marked abnormalities of lipoprotein metabolism and increased risk of atherogenesis. It is possible that qualitative as well as quantitative changes occur in lipoproteins to contribute to increased cardiovascular risk; for example, it is known that LDL exhibits heterogeneity, with small, dense LDL III particles being more atherogenic., Methods: We investigated LDL subfractions (measured by density gradient ultracentrifugation), VLDL subfractions, and post-heparin lipases in 12 patients with primary glomerular disease and 24-h albuminuria >2.5 g. These were compared to 23 age- and sex-matched controls., Results: Total LDL concentrations were similar in proteinuric patients and controls; however, there was a shift in subfraction distribution. The larger LDL I and LDL II particles were lower in the proteinuric group (29 +/- 24 vs 62 +/- 26 mg/dl P=0.011 and 121 +/- 80 vs 197 +/- 74 mg/dl P=0.028), whereas the concentration of atherogenic LDL III (small dense) was higher (135 +/- 64 vs 75 +/- 71 mg/dl P=0.0016). The concentration of total VLDL and both its subfractions were increased in the patients with proteinuria. Post-heparin hepatic and lipoprotein lipase levels were similar to normal., Conclusions: These findings suggest that the atherogenicity of LDL is increased in patients with heavy proteinuria because of the redistribution towards smaller denser particles. Since small, dense LDL has a lower affinity for the LDL receptor, the altered nature of the lipoprotein in proteinuria may decrease its clearance by the receptor-mediated pathway and contribute to the reduced clearance of LDL observed in this population. This may contribute to progression of renal failure or the accelerated vascular disease found in patients with heavy proteinuria.

A detailed longitudinal examination of plasma lipoprotein subfraction concentrations and compositions in pregnancy was performed with the objective of discovering the pattern of change in lipoprotein subfractions. Plasma triglyceride, cholesterol, very low density lipoprotein (VLDL1), very low density lipoprotein (VLDL2), intermediate density lipoprotein (IDL), low density lipoprotein (LDL) and its subfractions (LDL-I, LDL-II, LDL-III), and high density lipoprotein-cholesterol (HDL cholesterol) were quantified in 10 normal pregnant women from 10 weeks of gestation and at 5 weekly intervals thereafter, until 35 weeks of gestation, together with circulating hepatic lipase (at 10 and 35 weeks) and serum estradiol concentration. Median concentrations of VLDL1 (19-109 mg/dL), VLDL2 (17-103 mg/dL) and IDL (26-124 mg/dL) increased in parallel (maximum increase around 5-fold) as plasma triglyceride increased with advancing gestation. This contrasts with observations in the normal non-pregnant female, where higher concentrations of plasma triglyceride are associated with preferentially higher VLDL1 concentrations. The rise in IDL was also remarkable as this does not normally accompany changes in plasma triglyceride. LDL mass increased by 70% (200-353 mg/dL) between 10 and 35 weeks, and in 6 of the 10 women studied, the LDL subfraction pattern was modified towards a smaller denser pattern in a manner suggestive of a "threshold" transition, with the proportion of LDL-III increasing at the expense of LDL-II, whereas in the other 4 women, LDL subfraction profile remained unchanged throughout pregnancy. Interestingly, this "threshold" transition, if it occurred, did so at varying gestational ages and triglyceride concentrations for different women. The likelihood of LDL subfraction change and the final concentration of small, dense. LDL-III were related to the 10-week triglyceride concentration (R2 = 36.7%, P = 0.063) and to the rate of change in triglyceride for a given increment in estrogen (R2 = 48.6%, P = 0.025). In addition, VLDL1 mass exceeded 100 mg/dL during pregnancy only in those individuals in whom LDL profile perturbation was evident (chi 2, P < 0.001). LDL profile change was evident at the lowest triglyceride concentrations in the 2 individuals with the highest increments in triglyceride corrected for estrogen. On the basis of these longitudinal observations, we conclude the following: 1) as plasma triglyceride increases in pregnancy, there are parallel rises in median concentrations of VLDL1, VLDL2 and IDL, around 5-fold; 2) as a result of this progressive increase in plasma triglyceride, in particular in VLDL1, the LDL profile is altered in some individuals towards smaller, dense particles; 3) in general, the higher the initial (booking) fasting plasma triglyceride concentration or the larger the rate of change in triglyceride for a given increment in estradiol, the greater the probability of change in LDL profile towards smaller denser species; 4) significantly, LDL subclass perturbation towards smaller denser species occurs not in a gradual and progressive manner but exhibits "threshold" behavior; and finally, 5) this threshold is achieved at differing gestational ages and triglyceride concentrations for different women.

A radiochemical method for selective measurement of postheparin lipase activities was adapted to analyze lipoprotein lipase and hepatic lipase in preheparin plasma. The assay sensitivity was increased about four-fold by doubling both the volume of plasma used and the volume of lipolytic products taken for liquid scintillation counting, and was further improved by increasing the incubation period by 50% to 90 min. Rabbit antiserum to human hepatic lipase was unsuitable for the selective measurement of lipoprotein lipase because of apparent endogenous lipolytic activity. Preheparin hepatic lipase, however, was sensitive to inactivation by sodium dodecyl sulfate (SDS), the inhibition being greatest (> 90%) for plasma incubated with an equal volume of 40 mmol/L SDS. Intra- and interassay CVs for the two enzymes were 12.5-14.6% and 17.4-19.7%, respectively. In a cross-sectional study of 84 healthy subjects, pre- and postheparin hepatic lipase activities were higher in men than women, were correlated with indices of obesity, and were significantly correlated with one another, which explained the association of the former with plasma concentrations of high-density lipoprotein (HDL), HDL2, and small, dense low-density lipoproteins. There was no significant relationship between pre- and postheparin lipoprotein lipase activities, but the former were correlated with plasma concentrations of free fatty acids (FFA) and very-low-density lipoprotein. Apparently, preheparin activities of hepatic lipase, but not of lipoprotein lipase, may be a useful measure of the physiological function of "whole body" enzyme activity in cross-sectional and metabolic studies, where heparinization is not possible. Preheparin lipoprotein lipase activities, however, may reflect displacement of the enzyme by FFA and subsequent binding to remnants of triglyceride-rich lipoproteins.

Sequences regulating production of fimbriae were cloned from two enterotoxigenic Escherichia coli strains. One cloned region, from E. coli 0.25.H42, controlled expression of coli surface-associated (CS) antigen 4, whereas the function of the other, from E. coli 0167.H5, was unclear. Both regulators were related to the cfaD gene that controls expression of colonization factor antigen I (CFA/I) although low stringency conditions were required to show significant hybridization between cfaD and the regulatory fragment from E. coli 0167. The cloned regulatory genes promoted expression of CFA/I, CS1, CS2 and CS4 antigens but the levels of production in the presence of the 0167 regulator were lower than those promoted by the CS4 regulator or cfaD.

Two enterotoxigenic Escherichia coli strains of serotype 0.25.H42 that produced coli surface associated antigens CS4 and CS6 hybridized with a probe containing the cfaD sequence that regulates expression of colonization factor antigen CFA/I. Transformation of a cloned cfaD gene into some derivatives of the strains that were negative for CS4 and CS6 resulted in expression of CS4 but not CS6. By hybridization the sequence that regulated CS4 production in the wild type 025 strains was located on a plasmid that also encoded the CS6 antigen. The structural genes for the CS4 antigen were on a separate plasmid. The 025 strains carried a third plasmid encoding enterotoxin production which was therefore unlinked to regulation sequences or genes encoding CS antigens.

Enterotoxigenic Escherichia coli (ETEC) of serotype O114:H21, which produced only heat-labile enterotoxin (LT), gave mannose-resistant hemagglutination (MRHA) with bovine erythrocytes. One strain, E20738A, was shown to possess fimbriae of approximately 7.5 nm diameter. On SDS-PAGE two possible fimbrial polypeptides of molecular masses 17.5 and 15.5 kDa were seen; the 17.5-kDa band was the most prominent. Loss of LT and MRHA together from strain E20738A was associated with loss of a 100-MDa plasmid. An absorbed anti-strain E20738A serum reacted specifically with the 17.5- and 15.5-kDa polypeptides and bound to the intact fimbriae. This antiserum reacted positively in an ELISA with LT-positive E. coli strains of serogroups O8, O15, O48, O114, and O146. The antiserum did not react with ETEC carrying known colonization factors. The term coli-surface-associated antigen (CS) 17 has been used to describe the fimbriae.

Patterns of volatile metabolites in urine, as obtained by glass-capillary gas chromatography, were investigated by use of a nonparametric pattern-recognition method, in an effort to detect abnormalities associated with diabetes. We used threshold logic unit analysis on a data set consisting of normal subjects and those with diabetes mellitus, and could predict patterns for volatile metabolites as belonging to the proper class in 94.83% of the cases examined. In addition, a feature-extraction algorithm isolated those volatile constituents that are most useful in making the normal/diabetic classification. We used gas chromatography/mass spectrometry to identify important profile constituents. Finally, these same pattern-recognition methods indicated strong sex-related patterns in these volatiles.

Immunoglobulins, prepared from polyclonal rabbit antisera raised against Escherichia coli fimbrial antigens, colonization factor antigen (CFA)/I, and coli-surface-associated antigens (CS)1, CS2 and CS4, were used to assess antigenic cross-reactions between these four fimbrial types by Western immunoblotting. Antibodies in a serum, prepared against CS4, cross-reacted strongly with the fimbrial subunits of CFA/I, CS1 and CS2. Antibodies in sera prepared against CFA/I and CS1 gave weak reactions with CS1 or CFA/I respectively and also with CS2 and CS4, while the antiserum prepared against CS2 did not react. CS4 antiserum also reacted with the CS17 fimbrial subunit, but not with the subunits of fimbrial antigens: CFA/III, CS5, putative colonization factor (PCF) 0159:H4 or PCF0166.

Two hundred forty-four specimens of Escherichia coli isolated in Bangladesh and Thailand and identified as enterotoxin producers were tested for the presence of adhesion antigens by mannose-resistant hemagglutination, immunodiffusion, and enzyme-linked immunosorbent assays (ELISAs). Specific antisera to the antigens colonization factor antigen (CFA)/I, CFA/II (consisting of coli surface antigens [CS] 1, 2, and 3), and putative colonization factor antigen (PCF) 8775 (consisting of CS4, 5, and 6) were used in immunodiffusion tests and ELISAs. The results showed that the antigens could be detected in more strains by ELISA than by immunodiffusion. Twenty-nine percent of specimens of E. coli from Thailand and 47% from Bangladesh carried an adhesion antigen. Many of the strains had lost the ability to produce enterotoxins. Forty percent of strains from Thailand and 64% from Bangladesh that were still enterotoxigenic carried adhesion factors. These antigens were found on strains with heat-stable or heat-stable and heat-labile enterotoxin but not on strains producing only heat-labile enterotoxin. PCF8775 antigens were associated mainly with strains from Bangladesh, where 10 strains that produced only CS6 were detected.

Since 1969 strains of Salmonella wien that are resistant to multiple antibacterial drugs have caused widespread epidemics of enteritis in Europe and North Africa. Of 113 British strains examined between January 1970 and January 1977, 67 were multi-resistant. These strains and 22 strains from six other countries were examined to determine their plasmid content. Two plasmids were found in the vast majority of strains: an FIme factor, conferring resistance to ampicillin, chloramphenicol, kanamycin, streptomycin, spectinomycin, sulfonamides, and tetracyclines (ACKSSpSuT), and a nonautotransferring plasmid of resistance type ASSu. The FIme plasmids have dual incompatibility: they are incompatible with group FI factors and with the MP10 plasmid of Salmonella typhimurium, which belongs to a separate group. Other plasmids found in S. wien included principally a ColIa factor and an autotransferring plasmid that codes for ampicillin resistance and belongs to compatibility group I2. The similarity in plasmid content of strains isolated in widely separated areas suggests that they have a clonal origin.