IFN-gamma triggered STAT1-PKB/AKT signalling pathway influences the function of alloantigen reactive regulatory T cells

CD4+CD25+Foxp3+ regulatory T cells (Tregs) play a key role in the induction and maintenance of peripheral tolerance. Rapid and transient production of IFN-gamma by Tregs from mice tolerized to alloantigen in vivo has been shown to be critical for their regulatory function. This IFN-gamma has the potential to affect the function of cells present in the same local microenvironment as the Tregs, including the Tregs themselves. Here we investigated the mechanism by which IFN-gamma produced by Tregs triggered signaling pathways in alloantigen reactive Tregs themselves thereby influencing their function in vivo. We show that IFN-gamma production and STAT1 activation was increased, while STAT1-dependent PKB/AKT activation was downregulated in alloantigen reactive Tregs. Further, the activation of STAT1 was blocked in IFN-gamma receptor deficient as well as IFN-gamma-deficient Tregs, suggesting that IFN-gamma produced by the alloantigen reactive Tregs might act in an autocrine manner to induce STAT1 activation. Importantly, STAT1-deficient Tregs failed to control allograft rejection in vivo. Overall, these findings suggest that the IFN-gamma-induced STAT1-PKB/AKT signaling pathway plays a key role in upregulating the ability of alloantigen reactive Tregs to control graft rejection in vivo.

Role of protein Z and protein C in neonates with respiratory distress syndrome in Egypt (experience of one centre)

The aim of this study is to evaluate Protein Z (PTZ) and protein C (PTC) levels in newborns suffering from RDS, healthy preterm and full term newborns and to compare PTZ serum levels in RDS preterm infants with healthy preterm before and after recovery. Sixty newborn infants, recruited from the neonatal unit, were enrolled in the study and divided into 3 groups: Group (I): 20 preterm with RDS, Group (II): 20 healthy preterm control newborns (CPT) and Group (III): 20 healthy full term control newborns (CFT). Protein Z and C were measured using ELISA kits. The results of the study showed lower levels of protein Z were obtained in RDS group compared to preterm controls whose levels were significantly lower than in full-term controls. A significant increase in PTZ levels in RDS' group after recovery, when compared to preterm controls. In RDS, no significant correlations existed between PTZ levels (before and after recovery) and routine investigations except for a significant negative correlation with platelets count. No significant differences were found in PTC levels between the 3 studied groups. To conclude: premature newborns suffering from RDS showed decreased serum protein Z levels than normal preterm control newborns with further increase in its pattern after recovery. Further studies are recommended to evaluate the role of PTZ on outcome in premature newborns with RDS and to evaluate the relationship between protein PTZ and PTC and other coagulation factors incriminated in the development of RDS.

Single nucleotide polymorphisms of TSER, ATM, RecQ1 genes association with survival in pancrease cancer

e14590

Background: Pancreatic cancer (PaCa) is the 4th leading cause of cancer-related mortality in the U.S . We tried to determine whether ATM, RecQ1 gene polymorphisms correlate with gemcitabine (G) and TSER gene polymorphism with capecitabine (C) response and over all survival(OS). We also tested the hypothesis that PaCa pts homozygous for the S/S variant of the TSER will have a higher 6-month survival with C compared to historical controls. TS expression is regulated by a polymorphism in the TSER and has been shown that pts with S/S variant have high response rate and increased toxicity in colon cancer pts. ATM and recQ1 genes are involved with DNA damage response and repair and correlate with G response. Methods: DNA isolated from peripheral blood samples in 82 pts with Stage IV pancreatic cancer was tested for the TSER, ATM and RecQ1 gene polymorphisms. All patients were treated with G 1,000mg/m2 wkly for 3/4 wks. Pts homozygous for the S/S variant were treated with C, 2,000 mg/m2/day for 14 /21days. Pts were evaluated for response to therapy according to the RECIST. Results: 16 pts (19.5%) were positive for S/S variant of TSER, but only 4 (4.8%) were treated. The reasons for declining treatment were geographic, logistic or progression issues. Only 1 pt was evaluable, receiving at least 3 cycles of C . All pts needed dose reductions due to toxicities. Grade 3 hand foot syndrome, diarrhea and vomiting were dose limiting toxicities. No complete or partial responses were seen. The pt who received 3 cycles came off study due to progressive disease and the other 3 pts came of the study due to toxicities. TSER polymorphism was correlated to OS and only S/S variant was significant with a trend towards improved OS by log rank test and Kaplan Meier plot. ATM and RecQ1 gene polymorphisms subtypes did not correlate with G response and OS ( not statistically significant). Conclusions: Our study represents an initial effort to apply pharmacogenetics to PaCa therapy. 19.5% of pts had the S/S variant of the TSER polymorphism, but only 4.8% enrolled. C administration was associated with excess toxicity. The toxicities observed in this study appear to outweigh the benefit of using C in this pt population. There is no correlation between ATM and RecQ1 genotypes with OS. However the sample size is too small to draw conclusions.

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An evaluation of the effects of persistent environmental contaminants on the reproductive success of Great Blue Herons (Ardea herodias) in Indiana

Contaminants in Great Blue Herons (Ardea herodias) from Indiana were quantified to determine if levels were high enough to impair reproduction. During 2005 and 2006, 35 eggs were collected from 6 colonies and analyzed for contaminants. Between 30 and 101 nests were monitored in 7 colonies weekly over a 3-month period to determine reproductive and fledging success. Average levels (+/-SD) of polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and organochlorine pesticides in egg yolks were 3,101 (+/-4,737), 7.20 (+/-2.96), and 2,869 (+/-2,291) ppb, respectively. Reproductive success (average number of chicks fledged per active nest) and fledging success (number of chicks fledged per successful nest) averaged 1.52 and 1.92 chicks, respectively. Contaminant levels measured in eggs from this region are comparable to those observed not having affects on reproductive success elsewhere; therefore, factors other than environmental contamination may be affecting reproductive success of Great Blue Herons in study colonies.

Dynamic two-center interference in high-order harmonic generation from molecules with attosecond nuclear motion

We report a new dynamic two-center interference effect in high-harmonic generation from H2, in which the attosecond nuclear motion of H2+ initiated at ionization causes interference to be observed at lower harmonic orders than would be the case for static nuclei. To enable this measurement we utilize a recently developed technique for probing the attosecond nuclear dynamics of small molecules. The experimental results are reproduced by a theoretical analysis based upon the strong-field approximation which incorporates the temporally dependent two-center interference term.

Influence of solute carriers on the pharmacokinetics of CYP3A4 probes

We hypothesized that the assessment of baseline CYP3A4 activity is influenced by probe-specific differences in hepatocellular uptake mechanisms. There was no significant correlation between the erythromycin breath test (ERMBT) parameters and midazolam clearance in 30 cancer patients (R(2) < 0.01), regardless of their CYP3A5 genotype status. In cellular models overexpressing 10 different solute carriers, erythromycin uptake was significantly increased by OATP1A2 (P < 0.005) and OATP1B3 (P < 0.01). Midazolam was not a substrate for any of the tested transporters. In a separate cohort of 119 patients, 6 nonsynonymous variants in the OATP1B3 gene SLCO1B3 were identified. Individuals carrying two copies of the T allele at the 334 locus had a 2.4-fold lower value for ERMBT 1/T(max) (P = 0.001), a measure reflecting more rapid hepatic uptake. These findings suggest that differential affinities for solute carriers should be considered when selecting an appropriate phenotypic probe to allow tailored dosing of pharmaceuticals that are CYP3A4 substrates.

Modulation of erlotinib pharmacokinetics in mice by a novel cytochrome P450 3A4 inhibitor, BAS 100

Administration of BAS 100, a novel mechanism-based CYP3A4 inhibitor isolated from grapefruit juice, resulted in a 2.1-fold increase in erlotinib exposure following oral administration to wild-type and humanised CYP3A4 transgenic mice. This study illustrates the potential of BAS 100 to increase the low and variable oral bioavailability of erlotinib in cancer patients.

Phase I study of troxacitabine administered by continuous infusion in subjects with advanced solid malignancies

BACKGROUND

Troxacitabine is a novel L-nucleoside analogue. Preclinical studies showed improved activity with infusions of at least 3 days compared with bolus regimens, especially at concentrations >20 ng/ml. This phase I study tested the feasibility of achieving a troxacitabine steady-state concentration of 20 ng/ml for at least 72 h in patients with solid tumors.

PATIENTS AND METHODS

Patients with solid tumors received troxacitabine as a progressively longer infusion on days 1-4 of a 28-day cycle. The initial length of infusion and infusion rate were 48 h and 3 mg/m(2)/day.

RESULTS

Twenty-one patients were treated at infusion lengths that increased from 48 to 72 h and then 96 h. The infusion rate was decreased from 3 to 1.88 mg/m(2)/day due to toxicity. Dose-limiting toxicities consisted of grade 4 neutropenia (three) and grade 3 constipation (one). The maximum tolerated dose of continuous infusion troxacitabine in patients with solid tumors is 7.5 mg/m(2) administered over 96 h. This dose level resulted in steady-state drug concentration of at least 20 ng/ml for 72 h.

CONCLUSIONS

Administration of troxacitabine by continuous infusion achieved the prospectively defined target plasma concentration. Pharmacokinetics (PK) modeling coupled with real-time PK assessment was an efficient approach to conduct hypothesis-driven phase I trials.

Diabetes care in hospital--the impact of a dedicated inpatient care team

AIMS

At any given time, people with diabetes occupy approximately 5-10% of acute hospital beds. In addition, diabetes is associated with a greater length of stay (LOS). This is partially because of increased complexity of the cases but also because of unfamiliarity of dealing with the condition by other specialist teams.

METHODS

In 2002, with increasing pressure on acute hospital beds, a team was established to improve the care of inpatients with diabetes admitted to Derriford Hospital. The team consisted of five diabetes specialist nurses dedicated to inpatient care, supported by a consultant and specialist registrar diabetologist. A link nurse responsible for diabetes was appointed on every ward and each individual with a diagnosis of diabetes was identified on admission. We have compared LOS of all patients with diabetes admitted between January 2002 and December 2006.

RESULTS

LOS fell from a mean +/- se of 8.3 +/- 0.18 days in 2002 to 7.7 +/- 0.10 days in 2006 (P = 0.002). Significant falls were seen for emergency admissions (9.7 +/- 0.23 vs. 9.2 +/- 0.20, P < 0.001) but not elective admissions. The data show significant reductions in LOS for medical admissions (9.2 +/- 0.24 vs. 8.4 +/- 0.20, P < 0.001) but not surgical admissions. Over the same period, LOS for the total hospital population fell by 0.3 days (P < 0.001).

CONCLUSION

In conclusion, a team specifically employed to focus on inpatient diabetes care has a significant impact on LOS of this patient group.

Germline polymorphisms in EGFR and survival in patients with lung cancer receiving gefitinib

The purpose of this study was to evaluate associations between germline epidermal growth factor receptor (EGFR) variants involved in transcriptional regulation and overall survival in white patients with non-small-cell lung cancer (NSCLC) treated with the EGFR tyrosine kinase inhibitor, gefitinib. Of 175 consecutive patients treated with oral gefitinib (250 mg/day), 170 (median age: 67 years; 72% men) were evaluable for genotyping and survival. Fifty-five patients (33%) had stable disease and 17 (10%) had an objective response. The most common of four haplotypes was G-C (EGFR*1) at the EGFR -216G>T and -191C>A loci (frequency, 0.45). After adjusting for performance status, previous platinum-containing chemotherapy and occurrence of skin rash or diarrhea during the first treatment cycle in patients with performance status 0 or 1 (N=139), the absence of EGFR*1 was associated with significantly better survival (hazard ratio: 0.54; 95% confidence interval: 0.32-0.91; P=0.015). The results may help identify patients with NSCLC who can benefit from gefitinib treatment.

Influence of housing on the consequences of chronic mild stress in female rats

The chronic mild stress (CMS) paradigm was developed to model anhedonia in animals. The repeated administration of a series of unpredictable, mild stressors attempts to mimic the daily stress associated with the onset of clinical depression in humans. Male animals are predominantly used in these investigations despite significant, well-documented sex differences in human depression. In this study, the CMS procedure was modified to be more ecologically relevant to female animals. The effects of stress on sucrose preference, social interaction, rate of weight gain, and regularity of the estrous cycle in female Sprague-Dawley (SD) rats were evaluated in both single- and paired-housed rats, during 3 weeks each of baseline, CMS, and post-CMS phases. The results indicate that only single-housed rats exposed to stressors have a reduced rate of weight gain, significantly attenuated sucrose preference levels, and increased social interaction scores during the CMS phase of the study. Housing condition more than exposure to stress appeared to contribute to the disruption of estrous cycling in some animals. These data suggest that housing affords some protection from the negative consequences of CMS, at least in female rats, and that lack of social interaction in the single-housing condition may render females more vulnerable to stress-related illnesses. The development of paradigms that model human depression should emphasize sex-specific differences.

Dental health of long-term survivors of childhood cancer: The childhood cancer survivor study (CCSS)

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Background: This study describes the frequencies of and risk factors for altered oral health and dental development in pediatric patients who have survived childhood cancer. Methods: We identified 8,522 participants and 2,831 siblings in the CCSS with information on dental health. Dental outcomes of treatment and socioeconomic-demographic (SED) data, were analyzed using univariate and multivariate logistic regression models to estimate odds ratios (OR). Results: Survivors included 4,249 females (49.9%), 7,367 white non-Hispanic (86.5%). Median age at cancer diagnosis, 6.8y (range, 0–20 y); time from diagnosis to interview, 31.4 y (range, 17–54 y). Overall, 30% of survivors self-reported ≥ 1 oral-dental abnormality: microdontia (10%), hypodontia (8%), > 5 caries (55%), root stunting (6%), enamel hypoplasia (13%), gingivitis (7%). Compared to siblings, survivors were at increased risk of ≥ 1 oral-dental abnormalities when adjusted for SED (OR = 2.0, p<0.001). Increased risk of abnormalities was associated with being female (p<0.001) or white non-Hispanic (p=0.001), having an income < $20K (p=0.001) or lower education (p=0.004), and lack of health insurance (p=0.02). Patients with central nervous system tumors, neuroblastoma and soft tissue sarcoma had highest risk of abnormality (all P-values < 0.001). In multivariate models adjusted for SED, radiation dose to jaw, and exposure to increasing doses of alkylating agents increased risk of oral-dental abnormalities (radiation dose = 20 Gy OR = 5.6, p < 0.001; alkylating agent score OR=1.6, p<0.0001). Conclusions: Childhood cancer therapy results in adverse long- term oral-dental sequelae and is associated with specific treatment factors.

No significant financial relationships to disclose.

Probing orbital structure of polyatomic molecules by high-order harmonic generation

The effects of electronic structure and symmetry are observed in laser driven high-order harmonic generation for laser aligned conjugated polyatomic molecular systems. The dependence of the harmonic yield on the angle between the molecular axis and the polarization of the driving laser field is seen to contain the fingerprint of the highest occupied molecular orbitals in acetylene and allene, a good quantitative agreement with calculations employing the strong field approximation was found. These measurements support the extension of the recently proposed molecular orbital imaging techniques beyond simple diatomic molecules to larger molecular systems.

Descriptive Study Comparing Routine Hospital Administrative Data with the Vascular Society of Great Britain and Ireland's National Vascular Database

OBJECTIVE

To compare patient volume and outcomes in vascular surgery between an administrative data set (Hospital Episode Statistics) and a clinical database (National Vascular Database).

DESIGN

Descriptive study.

METHODS

Volume of cases determined by age, sex, year and procedure and in-hospital mortality by procedure for both datasets for patients undergoing either repair of abdominal aortic aneurysm, carotid endarterectomy or infrainguinal bypass over a three year period between 1st April 2001 and 31st March 2004.

RESULTS

There were 32,242 admissions with a mention of the three selected vascular procedures within the administrative data set compared to 8462 within the clinical database. For NHS trusts common to both datasets, there were twice as many procedures (16,923) recorded within the administrative dataset compared to the clinical database. Patient characteristics were similar across both databases. Further analysis limiting the administrative data to records attributed to consultants known to contribute to the clinical database showed much closer agreement with only 11% more repairs of abdominal aortic aneurysm recorded within the administrative dataset compared to the National Vascular Database.

CONCLUSIONS

There are significant differences in total numbers between HES and the NVD. If the National Vascular Database is to become a credible source of information on activity and outcomes for vascular surgery, there is a clear need to increase the number of contributing surgeons and to increase the completeness of data submitted. Further analysis at individual record level is needed to identify other reasons for discrepancies which could help to enhance data quality, both within Hospital Episode Statistics and within the National Vascular Database.