Anti-tumor necrosis factor-alpha therapy during murine Klebsiella pneumoniae bacteremia: increased mortality in the absence of liver injury.

Klebsiella pneumoniae is a leading cause of gram-negative bacterial pneumonia, often resulting in bacteremia concurrent with the localized pulmonary infection. The beneficial role of tumor necrosis factor (TNF)-alpha during pulmonary infection has been well documented; however, consequences of TNF-alpha production during systemic bacterial infection are controversial. A murine model of K. pneumoniae was developed to address this important issue. Liver-associated TNF-alpha mRNA was induced within 30 min after intravenous bacterial inoculation and remained elevated through 6 h before returning to near-baseline at 24 h postinfection. Intravenous K. pneumoniae infection induced liver cellular injury that was completely ablated when mice were pretreated with a neutralizing anti-TNF-alpha antibody. Interestingly, this reduction in liver injury failed to translate into improved survival. Mice receiving anti-TNF-alpha continued to succumb to the infection even out to day 10 postinfection. Bacterial clearance after TNF-alpha neutralization was significantly impaired at later time points during infection. Correlating with impaired bacterial clearance was diminished production of liver-associated MIP-2, MIP-1alpha, MCP-1, and interferon-gamma. Further evidence of diminished antibacterial immune responses was noted when the activational status of splenic natural killer cells in anti-TNF-alpha-treated mice was examined 24 h postinfection. Natural killer cells displayed decreased CD69 expression. Combined, these data indicate that the beneficial effects of TNF-alpha during systemic K. pneumoniae infection outweigh the detrimental effects of TNF-alpha-mediated hepatocyte cellular injury. Anti-TNF-alpha therapy, although preventing liver injury during blood-borne bacterial infection, results in a dampened anti-bacterial host response, resulting in decreased bacterial clearance and overall survival

A new nanocrystalline diamond-based biosensor for the detection of cardiovascular risk markers

In this paper, a new method to probe associative interactions of C-reactive protein (CRP) antigen with CRP antibody immobilized on a gold-interdigitated diamond electrodes was investigated. The CRP antigen detection was performed by capacitive/dielectric-constant measurements. Our results showed that the dynamic detection range using optimized conditions for a given antibody concentration (100 μg/ml) was found to be in the range 25-800 ng/ml of CRP-antigen. Biosensor developed in this study can be potentially used for detection of elevated CRP levels in suspected subjects for early diagnosis

Transhiatal esophagectomy in the profoundly obese: implications and experience.

BACKGROUND: Historically, obesity contraindicated an abdominal approach to the esophagogastric junction. The technique of transhiatal esophagectomy (THE) evolved without specific regard to body habitus. The dramatic increase in obese patients requiring an esophagectomy for complications of reflux disease prompted this evaluation of the impact of obesity on the outcomes of esophagectomy to determine whether profound obesity should contraindicate the transhiatal approach. METHODS: We used our Esophagectomy Database to identify 133 profoundly obese patients (body mass index [BMI] > or = 35 kg/m2) from among 2176 undergoing a THE from 1977 to 2006. This group was matched to a randomly selected, non-obese (BMI, 18.5 to 30 kg/m2) control population of 133 patients. Intraoperative, postoperative, and long-term follow-up results were compared retrospectively. RESULTS: Profoundly obese patients had significantly greater intraoperative blood loss (mean, 492.2 mL versus 361.8 mL, p = 0.001), need for partial sternotomy (18 versus 3, p = 0.001), and frequency of recurrent laryngeal nerve injury (6 versus 0, p = 0.04). The two groups did not differ significantly in the occurrence of chylothorax, wound infection, or dehiscence rate; length of hospital stay or need for intensive care unit stay; or hospital or operative mortality. Follow-up results for dysphagia, dumping, regurgitation, and overall functional score were also comparable between the two groups. CONCLUSIONS: With appropriate instrumentation, transhiatal esophagectomy in obese patients has similar morbidity and outcomes as in non-obese patients. Obesity, even when profound, does not contraindicate a transhiatal esophagectomy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/57503/6/Scipione 2007.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/57503/5/Benign BMI Control.txthttp://deepblue.lib.umich.edu/bitstream/2027.42/57503/4/Benign BMI CS07.txthttp://deepblue.lib.umich.edu/bitstream/2027.42/57503/3/CA BMI Control no pt id.txthttp://deepblue.lib.umich.edu/bitstream/2027.42/57503/2/CA BMI 35 CS.tx

Monitoring regulatory T cells as a prognostic marker in lung transplantation

Lung transplantation is the major surgical procedure, which restores normal lung functioning and provides years of life for patients suffering from major lung diseases. Lung transplant recipients are at high risk of primary graft dysfunction, and chronic lung allograft dysfunction (CLAD) in the form of bronchiolitis obliterative syndrome (BOS). Regulatory T cell (Treg) suppresses effector cells and clinical studies have demonstrated that Treg levels are altered in transplanted lung during BOS progression as compared to normal lung. Here, we discuss levels of Tregs/FOXP3 gene expression as a crucial prognostic biomarker of lung functions during CLAD progression in clinical lung transplant recipients. The review will also discuss Treg mediated immune tolerance, tissue repair, and therapeutic strategies for achieving in-vivo Treg expansion, which will be a potential therapeutic option to reduce inflammation-mediated graft injuries, taper the toxic side effects of ongoing immunosuppressants, and improve lung transplant survival rates

Incorporation of dUTP does not mediate mutation of A:T base pairs in Ig genes in vivo

Activation-induced cytidine deaminase (AID) protein initiates Ig gene mutation by deaminating cytosines, converting them into uracils. Excision of AID-induced uracils by uracil-N-glycosylase is responsible for most transversion mutations at G:C base pairs. On the other hand, processing of AID-induced G:U mismatches by mismatch repair factors is responsible for most mutation at Ig A:T base pairs. Why mismatch processing should be error prone is unknown. One theory proposes that long patch excision in G1-phase leads to dUTP-incorporation opposite adenines as a result of the higher G1-phase ratio of nuclear dUTP to dTTP. Subsequent base excision at the A:U base pairs produced could then create non-instructional templates leading to permanent mutations at A:T base pairs (1). This compelling theory has remained untested. We have developed a method to rapidly modify DNA repair pathways in mutating mouse B cells in vivo by transducing Ig knock-in splenic mouse B cells with GFP-tagged retroviruses, then adoptively transferring GFP+ cells, along with appropriate antigen, into primed congenic hosts. We have used this method to show that dUTP-incorporation is unlikely to be the cause of AID-induced mutation of A:T base pairs, and instead propose that A:T mutations might arise as an indirect consequence of nucleotide paucity during AID-induced DNA repair

Does reperfusion injury still cause significant mortality after lung transplantation?

ObjectivesSevere reperfusion injury after lung transplantation has mortality rates approaching 40%. The purpose of this investigation was to identify whether our improved 1-year survival after lung transplantation is related to a change in reperfusion injury.MethodsWe reported in March 2000 that early institution of extracorporeal membrane oxygenation can improve lung transplantation survival. The records of consecutive lung transplant recipients from 1990 to March 2000 (early era, n = 136) were compared with those of recipients from March 2000 to August 2006 (current era, n = 155). Reperfusion injury was defined by an oxygenation index of greater than 7 (where oxygenation index = [Percentage inspired oxygen] × [Mean airway pressure]/[Partial pressure of oxygen]). Risk factors for reperfusion injury, treatment of reperfusion injury, and 30-day mortality were compared between eras by using χ2, Fisher's, or Student's t tests where appropriate.ResultsAlthough the incidence of reperfusion injury did not change between the eras, 30-day mortality after lung transplantation improved from 11.8% in the early era to 3.9% in the current era (P = .003). In patients without reperfusion injury, mortality was low in both eras. Patients with reperfusion injury had less severe reperfusion injury (P = .01) and less mortality in the current era (11.4% vs 38.2%, P = .01). Primary pulmonary hypertension was more common in the early era (10% [14/136] vs 3.2% [5/155], P = .02). Graft ischemic time increased from 223.3 ± 78.5 to 286.32 ± 88.3 minutes in the current era (P = .0001). The mortality of patients with reperfusion injury requiring extracorporeal membrane oxygenation improved in the current era (80.0% [8/10] vs 25.0% [3/12], P = .01).ConclusionImproved early survival after lung transplantation is due to less severe reperfusion injury, as well as improvements in survival with extracorporeal membrane oxygenation

Size matters: A comparison of T1 and T2 peripheral non–small-cell lung cancers treated with stereotactic body radiation therapy (SBRT)

ObjectiveThe purpose of this study was to compare the outcomes and local control rates of patients with peripheral T1 and T2 non–small-cell lung cancer treated with stereotactic body radiation therapy.MethodsThe records of 40 consecutive patients treated with 3- or 5-fraction lung stereotactic body radiation therapy for peripheral, clinical stage I non–small-cell lung cancer were reviewed. Stereotactic body radiation therapy was delivered at a median dose of 60 Gy. Doses to organs at risk were limited based on the Radiation Therapy Oncology Group 0236 treatment protocol. Patients were staged clinically. Median follow was 12.5 months.ResultsTwenty-seven (67%) patients and 13 (33%) patients had T1 and T2 tumors, respectively. Thirty-seven (94%) patients were medically inoperable. Nine (23%) patients had chest wall pain after stereotactic body radiation therapy. Symptomatic pneumonitis developed in 4 (10%) patients. Increasing tumor size correlated with worse local control and overall survival. The median recurrence-free survival for T1 and T2 tumors was 30.6 months (95% confidence interval [CI], 26.9–34.2) and 20.5 months (95% CI, 14.3–26.5), respectively (P = .038). Local control at 2 years was 90% and 70% in T1 and T2 tumors, respectively (P = .03). The median survival for T1 and T2 tumors was 20 months (95% CI, 20.1–31.6) and 16.7 months (95% CI, 10.8–21.2), respectively (P = .073).ConclusionsStereotactic body radiation therapy for T2 non–small-cell lung cancer has a higher local recurrence rate and trended toward a worse survival than did T1 lesions. Tumor size is an important predictor of response to stereotactic body radiation therapy and should be considered in treatment planning

Genome-wide expression analyses of Campylobacter jejuni NCTC11168 reveals coordinate regulation of motility and virulence by flhA.

We examined two variants of the genome-sequenced strain, Campylobacter jejuni NCTC11168, which show marked differences in their virulence properties including colonization of poultry, invasion of Caco-2 cells, and motility. Transcript profiles obtained from whole genome DNA microarrays and proteome analyses demonstrated that these differences are reflected in late flagellar structural components and in virulence factors including those involved in flagellar glycosylation and cytolethal distending toxin production. We identified putative sigma(28) and sigma(54) promoters for many of the affected genes and found that greater differences in expression were observed for sigma(28)-controlled genes. Inactivation of the gene encoding sigma(28), fliA, resulted in an unexpected increase in transcripts with sigma(54) promoters, as well as decreased transcription of sigma(28)-regulated genes. This was unlike the transcription profile observed for the attenuated C. jejuni variant, suggesting that the reduced virulence of this organism was not entirely due to impaired function of sigma(28). However, inactivation of flhA, an important component of the flagellar export apparatus, resulted in expression patterns similar to that of the attenuated variant. These findings indicate that the flagellar regulatory system plays an important role in campylobacter pathogenesis and that flhA is a key element involved in the coordinate regulation of late flagellar genes and of virulence factors in C. jejuni