Differences in the respiratory swings in COPD and ILD candidates for lung transplantation: a critical concern interpreting central pulmonary pressures

Background

In different clinical scenarios (i.e., obesity, COPD, exercise, mechanical ventilation), the swings in intrathoracic pressure are much larger, and end-expiratory (Pee) pressure can be significantly greater than atmospheric pressure. In these scenarios, the intravascular (Piv) pulmonary pressure can overestimate the true transmural (tm) value and it is recommended to read the average of Piv over a few respiratory cycles (Pmrc) [1–3].

Purpose

To analyze the respiratory swings and the effect of esophageal pressure (PES) (as a surrogate of intrathoracic pressure) on the reading of Piv tracings during the RHC at rest in COPD and interstitial lung disease (ILD) candidates for lung transplantation (LTx).

Methods

Thirty-one COPD (15) and ILD (16) candidates for LTx underwent RHC. End-expiratory and mean respiratory cycle measurements were obtained. The respiratory swing was estimated as the difference between maximum-minimum values of Piv. Ten patients (5 COPD/5 ILD) underwent simultaneous RHC and PES (Micro-balloon Esophageal Catheter, LATITUDE) to assess the Ptm (Piv − PES) [4].

Results

Both demographic (11F/20M, 60±7 yrs, 25±4 kg/m2) and hemodynamic data (mPAP 24±9 mmHg, pulmonary arterial occlusion pressure [PAOP] 8.6±4 mmHg, right atrial pressure [RAP] 5.2±3.9 mmHg, pulmonary vascular resistance 3.5±2.6 Wu) did not show significant differences between ILD and COPD except the cardiac index (ILD: 2.8±0.8 vs. COPD: 2.4±0.3 L/min/m2). Intravascular RAPee and PAOPee were higher than mrc values in both groups (Fig 1). However, transmural RAPee and PAOPee were similar to and correlated with (r=0.62 and 0.69, respectively; p<0.05) transmural Pmrc values. PESee values were positive in COPD and ILD (3.0±2.2 vs. 3.3±2.0 mmHg, NS). All ILD had negative PESmrc values and were lower than COPD patients (−1.76±1.7 vs. 0.78±1.6 mmHg, p<0.05). ILD PES swings were higher than COPD (10.9±3.7 vs. 8.3±1.4 mmHg), although it did not reach statistical significance (p=0.08). The lower forced vital capacity (%), the more negative the PESmrc (Fig 2A). ILD pts showed higher transmural to intravascular Pmrc (p<0.05) (Fig 2B).

Conclusion

End-expiratory intravascular RAP and PAOP overestimates the mean respiratory cycle pressures in COPD and ILD candidates for LTx. Averaging pulmonary vascular pressure tracings over the respiratory cycle would be accurate in COPD but could underestimate transmural values in ILD candidates for LTx. The reading of mean respiratory cycle pressure could not be enough to correct the pulmonary pressures measurement error associated with the presence of large swings of intrathoracic pressure.

Funding Acknowledgement

Type of funding sources: None.

Toll-Like Receptor 7 (TLR-7) and TLR-9 Agonists Improve Hepatitis C Virus Replication and Infectivity Inhibition by Plasmacytoid Dendritic Cells

Plasmacytoid dendritic cells (pDCs) are innate immune cells with high antiviral activity triggered by Toll-like receptor 7 (TLR-7) and TLR-9 stimulation. Moreover, they are important mediators between innate and adaptive immunity. Although nowadays there is available an effective therapeutic arsenal against hepatitis C virus (HCV), a protective vaccine is not available. We have analyzed the pDCs' response to HCV infection in a hepatitis C virus (HCV)-Huh7.5 virus-cell system, which allows completion of the virus infectious cycle. pDCs were cocultured following human immunodeficiency virus (HIV) aldrithiol-2 (AT-2 [TLR-7 agonist]) inactivation and CpG (TLR-9 agonist) stimulation. We employed three virus derivatives-wild-type Jc1, interferon (IFN)-resistant virus IR, and high-replicative-fitness virus P100-in order to explore additional IFN-α-related virus inhibition mechanisms. pDCs inhibited HCV infectivity and replication and produced IFN-α. After TLR-7 and TLR-9 stimulation, inhibition of infectivity and IFN-α production by pDCs were enhanced. TLR-7 stimulation drove higher TNF-related apoptosis-inducing ligand (TRAIL) expression in pDCs. Additionally, TLR-7- and TLR-9-stimulated pDCs exhibited a mature phenotype, improving the antigen presentation and lymph node homing-related markers. In conclusion, pDCs could serve as a drug target against HCV in order to improve antiviral activity and as an enhancer of viral immunization.IMPORTANCE We implemented a coculture system of pDCs with HCV-infected hepatoma cell line, Huh7.5. We used three HCV derivatives in order to gain insight into pDCs' behavior against HCV and associated antiviral mechanisms. The results with this cell coculture system support the capacity of pDCs to inhibit HCV replication and infectivity mainly via IFN-α, but also through additional mechanisms associated with pDC maturation. We provided evidence that TLR agonists can enhance antiviral pDCs' function and can induce phenotypic changes that may facilitate the interplay with other immune cells. These findings suggest the possibility of including TLR agonists in the strategies of HCV vaccine development.

Prognostic markers for colorectal cancer: estimating ploidy and stroma

Background

We report here the prognostic value of ploidy and digital tumour-stromal morphometric analyses using material from 2624 patients with early stage colorectal cancer (CRC).

Patients and methods

DNA content (ploidy) and stroma-tumour fraction were estimated using automated digital imaging systems and DNA was extracted from sections of formalin-fixed paraffin-embedded (FFPE) tissue for analysis of microsatellite instability. Samples were available from 1092 patients recruited to the QUASAR 2 trial and two large observational series (Gloucester, n = 954; Oslo University Hospital, n = 578). Resultant biomarkers were analysed for prognostic impact using 5-year cancer-specific survival (CSS) as the clinical end point.

Results

Ploidy and stroma-tumour fraction were significantly prognostic in a multivariate model adjusted for age, adjuvant treatment, and pathological T-stage in stage II patients, and the combination of ploidy and stroma-tumour fraction was found to stratify these patients into three clinically useful groups; 5-year CSS 90% versus 83% versus 73% [hazard ratio (HR) = 1.77 (95% confidence interval (95% CI): 1.13-2.77) and HR = 2.95 (95% CI: 1.73-5.03), P < 0.001].

Conclusion

A novel biomarker, combining estimates of ploidy and stroma-tumour fraction, sampled from FFPE tissue, identifies stage II CRC patients with low, intermediate or high risk of CRC disease specific death, and can reliably stratify clinically relevant patient sub-populations with differential risks of tumour recurrence and may support choice of adjuvant therapy for these individuals.

A study of genomic instability in early preneoplastic colonic lesions

It is difficult to explain the differential rates of progression of premalignant colonic lesions and differences in behaviour of morphologically similar lesions. Heterogeneity for microsatellite instability (MSI) and promoter methylation in driving these phenomena forward may explain this; however, no previous analysis has examined this in detail at the gland level, the smallest unit of colorectal premalignant lesions. We aimed to carry out an analysis of gland level genomic instability for MSI and promoter methylation. MSI occurred significantly more frequently (20%) in colonic glands than has previously been observed in whole colorectal polyps. Significant promoter methylation was seen in MLH1, PMS2, MLH3 and MSH3 as well as significant heterogeneity for both MSI and promoter methylation. Methylation and MSI may have a significant role in driving forward colorectal carcinogenesis, although in the case of MSI, this association is less clear as it occurs significantly more frequently than previously thought, and may simply be a passenger in the adenoma-carcinoma sequence. Promoter methylation in MLH1, MLH3, MSH3 and PMS2 was also found to be significantly associated with MSI and should be investigated further. A total of 273 colorectal glands (126 hyperplastic, 147 adenomatous) were isolated via laser capture microdissection (targeted at regions of MLH1 loss) from 93 colonic polyps and tested for MSI, and promoter methylation of the DNA mismatch repair genes MLH1, MSH2, MLH3, MSH6, PMS2, MGMT and MLH3 via methylation specific multiplex ligation-dependent probe amplification. Logistic regression modelling was then used to identify significant associations between promoter methylation and gland histological type and MSI status.

Oncolytic measles virus strains have significant antitumor activity against glioma stem cells

Glioblastoma (GBM) is the most common primary brain tumor in adults and has a dismal prognosis despite multimodality treatment. Given the resistance of glioma stem cells (GSC) to chemotherapy and radiation therapy, their eradication could prevent tumor recurrence. We sought to evaluate the antitumor activity of measles virus (MV) derivatives against GSC. We generated neurosphere cultures from patient-derived primary tumor GBM xenografts, and we characterized them for the GSC markers CD133, SOX2, Nestin, ATF5 and OLIG2. Using the MV-strains MV-GFP, MV-CEA and MV-NIS we demonstrated infection, viral replication and significant cytopathic effect in vitro against GSC lines. In tumorigenicity experiments, GBM44 GSC were infected with MV in vitro and subsequently implanted into the right caudate nucleus of nude mice: significant prolongation of survival in mice implanted with infected GSC was observed, compared with mock-infected controls (P=0.0483). In therapy experiments in GBM6 and GBM12 GSC xenograft models, there was significant prolongation of survival in MV-GFP-treated animals compared with inactivated virus-treated controls (GBM6 P=0.0021, GBM12 P=0.0416). Abundant syncytia and viral replication was demonstrated in tumors of MV-treated mice. Measles virus derivatives have significant antitumor activity against glioma-derived stem cells in vitro and in vivo.

The proportion of tumor-stroma as a strong prognosticator for stage II and III colon cancer patients: validation in the VICTOR trial

BACKGROUND

The intra-tumor stroma percentage in colon cancer (CC) patients has previously been reported by our group as a strong independent prognostic parameter. Patients with a high stroma percentage within the primary tumor have a poor prognosis.

PATIENTS AND METHODS

Tissue samples from the most invasive part of the primary tumor of 710 patients (52% Stage II, 48% Stage III) participating in the VICTOR trial were analyzed for their tumor-stroma percentage. Stroma-high (>50%) and stroma-low (≤50%) groups were evaluated with respect to survival times.

RESULTS

Overall and disease-free survival times (OS and DFS) were significantly lower in the stroma-high group (OS P<0.0001, hazard ratio (HR)=1.96; DFS P<0.0001, HR=2.15). The 5-year OS was 69.0% versus 83.4% and DFS 58.6% versus 77.3% for stroma-high versus stroma-low patients.

CONCLUSION

This study confirms the intra-tumor stroma ratio as a prognostic factor. This parameter could be a valuable and low cost addition to the TNM status and next to current high-risk parameters such as microsatellite instability status used in routine pathology reporting. When adding the stroma-parameter to the ASCO criteria, the rate of 'undertreated' patients dropped from 5.9% to 4.3%, the 'overtreated' increased with 6.8% but the correctly classified increased with an additional 14%.

[Capillary beta-hydroxybutyrate determination for monitoring diabetic ketoacidosis]

BACKGROUND AND OBJECTIVE

Diabetic ketoacidosis (DKA) is the most severe acute metabolic complication of type 1 diabetes mellitus. Insulin treatment is commonly guided by plasma glucose levels and changes in venous blood gases, while β-hydroxibutyrate (BHB) levels are rarely measured. The study objective was to evaluate the value of capillary BHB monitoring in the course and resolution of DKA.

PATIENTS AND METHODS

Thirty patients with type 1 diabetes admitted for DKA were enrolled. A standard protocol including monitoring of blood glucose, venous blood gases, semiquantitative ketonuria, and capillary BHB was used. Patients were divided into three groups by time to DKA resolution (group 1:<24 h, group 2: 24-48 h, group 3: >48 h), and BHB results were compared to all other biochemical measurements.

RESULTS

Mean laboratory results upon admission were: blood glucose 415 (standard deviation [SD] 106) mg/dL; bicarbonate 9.6 (SD 1.5) mmol/L; pH 7.13 (SD 0.04); BHB 4.33 (SD 0.48) mmol/L, and ketonuria 3+ in 22 patients and 4+ in 6. BHB correlated well with bicarbonate (r=-0.24139; P=0.0161) and pH (r=-0.56419; P<0.0001). BHB normalized earlier than ketonuria in all cases (group 1: 15.5 vs 18.8 hours P<0.05; group 2: 18.2 vs 23.5 hours P<0.01; group 3: 37.3 vs 41.7 hours P<0.01). Ten percent of patients still had ketonuria when blood ketone levels were already normal (<0.5 mmol/L).

CONCLUSION

BHB measurement is an easy, practical, and reliable monitoring method in DKA and may be used as a parameter to adjust insulin treatment.

Current and potential usefulness of pneumococcal urinary antigen detection in hospitalized patients with community-acquired pneumonia to guide antimicrobial therapy

BACKGROUND

The role of pneumococcal urinary antigen detection in the treatment of adults with community-acquired pneumonia (CAP) is not well defined. We assessed the usefulness of pneumococcal urinary antigen detection in the diagnosis and antimicrobial guidance in patients hospitalized with CAP.

METHODS

A prospective study of all adults hospitalized with CAP was performed from February 2007 through January 2008. To evaluate the accuracy of the test, we calculated its sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios. The gold standard used for diagnosis of pneumococcal pneumonia was isolation in blood or pleural fluid (definite diagnosis) and isolation in sputum (probable diagnosis). Antibiotic modifications, complications, and mortality were analyzed.

RESULTS

A total of 474 episodes of CAP were included. Streptococcus pneumoniae was the causative pathogen in 171 cases (36.1%). It was detected exclusively by urinary antigen test in 75 cases (43.8%). Sixty-nine patients had CAP caused by a pathogen other than S pneumoniae. Specificity was 96%, positive predictive value ranged from 88.8% to 96.5%, and the positive likelihood ratio ranged from 14.6 to 19.9. The results of the test led the clinicians to reduce the spectrum of antibiotics in 41 patients. Pneumonia was cured in all of them. Potentially, this optimization would be possible in the 75 patients diagnosed exclusively by the test.

CONCLUSION

When its findings are positive, the pneumococcal urinary antigen test is a useful tool in the treatment of hospitalized adult patients with CAP because it may allow the clinician to optimize antimicrobial therapy with good clinical outcomes.

Clonality assessment and clonal ordering of individual neoplastic crypts shows polyclonality of colorectal adenomas

BACKGROUND & AIMS

According to the somatic mutation theory, monoclonal colorectal lesions arise from sequential mutations in the progeny of a single stem cell. However, studies in a sex chromosome mixoploid mosaic (XO/XY) patient indicated that colorectal adenomas were polyclonal. We assessed adenoma clonality on an individual crypt basis and completed a genetic dependency analysis in carcinomas-in-adenomas to assess mutation order and timing.

METHODS

Polyp samples were analyzed from the XO/XY individual, patients with familial adenomatous polyposis and attenuated familial adenomatous polyposis, patients with small sporadic adenomas, and patients with sporadic carcinoma-in-adenomas. Clonality was analyzed using X/Y chromosome fluorescence in situ hybridization, analysis of 5q loss of heterozygosity in XO/XY tissue, and sequencing of adenomatous polyposis coli. Individual crypts and different phenotypic areas of carcinoma-in-adenoma lesions were analyzed for mutations in adenomatous polyposis coli, p53, and K-RAS; loss of heterozygosity at 5q, 17p, and 18q; and aneuploidy. Phylogenetic trees were constructed.

RESULTS

All familial adenomatous polyposis-associated adenomas and some sporadic lesions had polyclonal genetic defects. Some independent clones appeared to be maintained in advanced adenomas. No clear obligate order of genetic events was established. Top-down growth of dysplastic tissue into neighboring crypts was a possible mechanism of clonal competition.

CONCLUSIONS

Human colorectal microadenomas are polyclonal and may arise from a combination of host genetic features, mucosal exposures, and active crypt interactions. Analyses of tumor phylogenies show that most lesions undergo intermittent genetic homogenization, but heterotypic mutation patterns indicate that independent clonal evolution can occur throughout adenoma development. Based on observations of clonal ordering the requirement and timing of genetic events during neoplastic progression may be more variable than previously thought.