The impact of Aldehyde dehydrogenase 1 expression on prognosis for metastatic colon cancer

Background

Cancer stem cells may be associated with tumor progression and prognosis for colon cancer. We hypothesized that expression of Aldehyde dehydrogenase 1 (ALDH1) would increase with tumor progression and be associated with survival.

Methods

Tissue was obtained from resection specimens for isolation of cancer stem cells. In addition, paraffin blocks from resected colon cancers with normal colon, primary tumor, and lymph node and liver metastasis from 2000 to 2010 were identified and stained with ALDH1.

Results

In in vitro models (adherent and tumor spheres) ALHD1+ cells grew more efficiently than ALDH1− cells. ALDH1 expression was highest in peritumoral crypt cells (0.137 μm², 95% confidence interval [CI] 0.125–0.356) and normal crypts (median 0.091 μm², 95% CI 0.064–0.299) followed by lymph node metastasis (median 0.025 μm², 95% CI 0–0.131) and the primary cancers (median 0.014 μm², 95% CI 0.0123–0.154). Samples were divided into high and low ALDH1 expression. Survival was associated with expression in the primary tumor (9 versus 23 mo, P = 0.0016) expression but not peritumoral tissue (21 versus 20.5 mo, P = 0.32), normal colon (19 versus 27 mo, P = 0.289), or lymph node metastasis (23 versus 21 mo, P = 0.69). On univariate analysis, ALDH1 expression and grade were associated with survival but ages, number of lymph node metastasis, race, or grade were not associated. On multivariate analysis, only ALDH1 status continued to be associated with survival, odds ratio 4.4, and P = 0.011.

Conclusions

ALDH1 is indicative of stemness and is a biomarker marker in colon cancer. Expression did not increase with progression from normal colon to primary tumors and metastasis.     

The effects of propofol and dexmedetomidine infusion on fluid responsiveness in critically ill patients

Background

We studied the effects of propofol or dexmedetomidine on preload dependency and fluid responsiveness in critically ill patients.

Methods

In the study, we included 91 patients with acute circulatory failure (70 ± 15 y) who received propofol (n = 45 patients, PROP group) or dexmedetomidine (n = 46 patients, DEX group). An initial passive leg-raising (PLR 1) test was performed in all patients to evaluate preload dependency at baseline. Propofol and dexmedetomidine were infused and titrated according to the Richmond Agitation Sedation Scale; the results ranged from −2 to −1, and the bispectral index values ranged from 60–75. A second PLR test (PLR 2) was performed before administration of a 250-mL normal saline fluid challenge over a 5-min period. We obtained central venous pressure and cardiac index (CI) measurements before and after the two PLR tests and volume expansion. An increase of ≥10% in CI during PLR was considered to be a positive test finding that was indicative of preload dependency, whereas an increase of <10% in CI during PLR was considered to be a negative test finding.

Results

At baseline, 22 of 45 patients had negative PLR 1 in the PROP group, whereas 20 of 46 patients had negative PLR 1 in the DEX group. After propofol or dexmedetomidine sedation, there were significant decreases in CI (−9.5% [±6.6%] versus −16.4% [±8.5%], P < 0.001) in the PROP and DEX groups, respectively. In the PROP group, there were significant increases in CI (+18.4% [±9.5%] versus +10.7% [±12.3%], P < 0.05) induced by PLR 2 compared with that induced by PLR 1. In the DEX group, there were no significant increases in CI (+13.2% [±14.9%] versus +12.8% [±17.7%]) induced by PLR 2 compared with that induced by PLR 1. Although the mean arterial pressure values increased comparably with the volume expansion observed in both groups, the volume expansion resulted in a significantly higher increase in CI compared with the baseline values in the PROP group (3.2 ± 0.8 versus 3.2 ± 0.7 L/min/m²) but not in the DEX group (2.9 ± 0.7 versus 3.1 ± 0.8 L/min/m², P < 0.05).

Conclusions

We observed that propofol infusion, but not dexmedetomidine infusion, can increase preload dependency and fluid responsiveness in patients with circulatory failure.     

Ghrelin decreases motor deficits after traumatic brain injury

Background

Pharmacologic therapy for traumatic brain injury (TBI) has remained relatively unchanged for decades. Ghrelin, an endogenously produced peptide, has been shown to prevent apoptosis and blood-brain barrier dysfunction after TBI. We hypothesize that ghrelin treatment will prevent neuronal degeneration and improve motor coordination after TBI.

Materials and methods

A weight drop model created severe TBI in three groups of BALB/c mice: Sham, TBI, and TBI + ghrelin (20 μg intraperitoneal ghrelin). Brain tissue was examined by hematoxylin and eosin and Fluoro-Jade B (FJB) staining to evaluate histologic signs of injury, cortical volume loss, and neuronal degeneration. Additionally, motor coordination was assessed.

Results

Ghrelin treatment prevented volume loss after TBI (19.4 ± 9.8 mm³versus 71.4 ± 31.4 mm³; P < 0.05). Similarly, although TBI increased FJB–positive neuronal degeneration, ghrelin treatment decreased FJB staining in TBI resulting in immunohistologic patterns similar to sham. Compared with sham, TBI animals had a significant increase in foot faults at d 1, 3, and 7 (2.75 ± 0.42; 2.67 ± 0.94; 3.33 ± 0.69 versus 0.0 ± 0.0; 0.17 ± 0.19; 0.0 ± 0.0; P < 0.001). TBI + ghrelin animals had significantly decreased foot faults compared with TBI at d 1, 3, and 7 (0.42 ± 0.63; 0.5 ± 0.43; 1.33 ± 0.58; P versus TBI <0.001; P versus sham = NS).

Conclusions

Ghrelin treatment prevented post-TBI cortical volume loss and neurodegeneration. Furthermore, ghrelin improved post-TBI motor deficits. The mechanisms of these effects are unclear; however, a combination of the anti-apoptotic and inflammatory modulatory effects of ghrelin may play a role. Further studies delineating the mechanism of these observed effects are warranted.     

Membrane potential-dependent uptake of F-triphenylphosphonium–a new voltage sensor as an imaging agent for detecting burn-induced apoptosis

Background

Mitochondrial dysfunction has been closely related to many pathologic processes, such as cellular apoptosis. Alterations in organelle membrane potential are associated with mitochondrial dysfunction. A fluorine-18 labeled phosphonium compound: ¹⁸F-triphenylphosphonium (¹⁸F-TPP) was prepared to determine its potential use as a mitochondria-targeting radiopharmaceutical to evaluate cellular apoptosis.

Methods

Studies were conducted in both ex vivo cell lines and in vivo using a burned animal model. Uptake of ¹⁸F-TPP was assessed in PC-3 cells by gamma counting under the following conditions: graded levels of extracellular potassium concentrations, incubation with carbonyl cyanide m-chlorophenylhydrazone and staurosporine. Apoptosis was studied in a burn animal model using terminal deoxynucleotidyl transferase dUTP nick end labeling staining and simultaneous assessment of ¹⁸F-TPP uptake by biodistribution.

Results

We found that stepwise membrane depolarization by potassium (K) resulted in a linear decrease in ¹⁸F-TPP uptake, with a slope of 0.62 ± 0.08 and a correlation coefficient of 0.936 ± 0.11. Gradually increased concentrations of m-chlorophenylhydrazone lead to decreased uptake of ¹⁸F-TPP. Staurosporine significantly decreased the uptake of ¹⁸F-TPP in PC-3 cells from 14.2 ± 3.8% to 5.6 ± 1.3% (P < 0.001). Burn-induced significant apoptosis (sham: 4.4 ± 1.8% versus burn: 24.6 ± 6.7 %; P < 0.005) and a reduced uptake of tracer in the spleens of burn-injured animals as compared with sham burn controls (burn: 1.13 ± 0.24% versus sham: 3.28 ± 0.67%; P < 0.005). Biodistribution studies demonstrated that burn-induced significant reduction in ¹⁸F-TPP uptake in spleen, heart, lung, and liver, which were associated with significantly increased apoptosis.

Conclusions

¹⁸F-TPP is a promising new voltage sensor for detecting mitochondrial dysfunction and apoptosis in various tissues.     

CD16 inhibition increases host survival in a murine model of severe sepsis

Background

To investigate the therapeutic effect of monoclonal antibody (mAb)–induced CD16 (FcγRIII) inhibition in a murine model of high-grade (severe) sepsis.

Materials and methods

In a prospective controlled animal study, 2 μg of CD16/32 (FcγRIII/FcγRII) or the same volume of normal saline was administered intraperitoneally to BALB/c FcγRII^−/− mice at the time of cecal ligation and puncture (CLP) in a murine model of high-grade sepsis. Subcutaneous administration of CD16/32 (0.5 μg/24 h) or normal saline continued for 7 d. Survival was evaluated, and the underlying therapeutic mechanism of mAb-induced CD16 inhibition was investigated.

Results

CD16 expression was significantly increased on peripheral blood CD14⁺ monocytes from mice with high-grade sepsis compared with non–septic control mice (1579.40 ± 217.75 versus 461.10 ± 36.13; P < 0.05). CD16/32 mAb treatment increased the survival of mice with high-grade sepsis (P < 0.05) and significantly decreased their elevated levels of serum tumor necrosis factor α (36.70 ± 9.97 versus 52.60 ± 10.69; P < 0.05) and interleukin 1β (1149.40 ± 244.09 versus 2605.60 ± 353.74; P < 0.05) at 6 and 24 h after CLP, respectively. Moreover, CD16/32 mAb-treated mice with high-grade sepsis had fewer bacteria in their blood and peritoneal lavage than mice just treated with normal saline at 24 h after CLP (P < 0.05).

Conclusions

CD16/32 mAb-induced CD16 inhibition increased the survival of mice with high-grade sepsis, which may have been because of the concomitant suppression of tumor necrosis factor α and interleukin 1β as well as the enhancement of monocyte phagocytosis. Thus, targeted inhibition of CD16 can potentially improve the outcome of selected patients with severe sepsis.     

Colorectal cancer patient–derived xenografted tumors maintain characteristic features of the original tumors

Background

Despite significant improvements in colon cancer outcomes over the past few decades, preclinical development of more effective therapeutic strategies is still limited by the availability of clinically relevant animal models. To meet those clinical unmet needs, we generated a well-characterized in vivo preclinical platform for colorectal cancer using fresh surgical samples.

Methods

Primary and metastatic colorectal tumor tissues (1–2 mm³) that originate from surgery were implanted into the subcutaneous space of nude mice and serially passaged in vivo. Mutation status, hematoxylin and eosin staining, short tandem repeat profiling, and array comparative genomic hybridization were used to validate the similarity of molecular characteristics between the patient tumors and tumors obtained from xenografts.

Results

From surgical specimens of 143 patients, 97 xenograft models were obtained in immunodeficient mice (establish rate = 67%). Thirty-nine xenograft models were serially expanded further in mice with a mean time to reach a size of 1000–1500 mm³ of 90 ± 20 d. Histologic and immunohistochemical analyses revealed a high degree of pathologic similarity including histologic architecture and expression of CEA, CK7, and CD20 between the patient and xenograft tumors. Molecular analysis showed that genetic mutations, genomic alterations, and gene expression patterns of each patient tumor were also well conserved in the corresponding xenograft tumor.

Conclusions

Xenograft animal models derived from fresh surgical sample maintained the key characteristic features of the original tumors, suggesting that this in vivo platform can be useful for preclinical development of novel therapeutic approaches to colorectal cancers.     

Pretreatment of Transfused Donor Splenocytes and Allografts With Mitomycin C Attenuates Acute Rejection in Heart Transplantation in Mice

Objective

The aim of this study was to investigate the effect of pretreatment of donor splenocytes and grafts with mitomycin C (MMC) on heart allograft survival, as well as to demonstrate the mechanism of function.

Methods

Donor splenocytes from Balb/C mice were incubated with MMC (40 μg/mL) in vitro and then transfused into recipients (C57BL/6 mice). The heart allograft was perfused with MMC before harvest. Graft survival and histopathology were examined. Lymphocyte activation, regulatory T cells, and donor splenocyte apoptosis were examined with the use of flow cytometry.

Results

MMC incubation in vitro induced apoptosis of donor splenocytes (15.5 ± 2.3% vs 23.2 ± 4.2%; P < .01). Either intravenous injection of MMC-treated donor splenocytes or transplantation of allograft pretreated with MMC prolonged heart allograft mean survival time from 7 ± 0.8 days to 20.5 ± 1.9 days or 10 ± 0.9 days, respectively (both P < .01). A combination of MMC-pretreated donor splenocyte transfusion and allografts showed the best effect on prolongation of graft survival (28.5 ± 1.8 days). Activation of CD4⁺ T cells in spleen and peripheral lymph nodes of recipients was significantly inhibited by either MMC-splenocyte transfusion or the combination treatment. Meanwhile, the percentage of CD4⁺CD25⁺Foxp3⁺ regulatory T cells in the spleen was increased in the MMC-splenocyte transfusion group (15.5 ± 1.1% vs 18.2 ± 0.9%; P < .05).

Conclusions

Both injection of MMC-conditioned donor splenocytes and MMC-conditioned allograft have effects on prolongation of heart allograft survival in mice, and MMC-conditioned donor splenocytes might play an essential role. MMC pretreatment induced regulatory T cells likely through induction of donor splenocyte apoptosis, and thus it inhibited T-cell activation.     

Novel anti-adhesive barrier Biobarrier reduces growth of colon cancer cells

Background

Postoperative peritoneal carcinomatosis together with adhesion formation are considered as two major clinical complications after resection of malignant abdominal tumors, jeopardizing the beneficial effect of the curative surgery. Biobarrier is a novel anti-adhesive barrier fulfilling the criteria for a good adhesion preventive agent, possessing biochemical properties that may enable it to function as a dual efficient device, reducing both adhesion and tumor development. This study aims to evaluate the effect of novel anti-adhesive device Biobarrier on intra-abdominal tumor progression.

Materials and methods

Cells from cancer cell line BN7005H1D2 were treated with Biobarrier to determine the effect of Biobarrier on cell attachment and viability in vitro. For the in vivo experiments, bilateral peritoneal trauma was inflicted in a reproducible syngeneic rat model. To mimic the clinical situation, the animals received an intraperitoneal injection of BN7005H1D2 cancer cells at the end of surgery, resembling perioperative tumor spill after intraperitoneal instillation of Biobarrier. Animals without given anti-adhesive treatment were used as control.

Results

Biobarrier applied in vitro hindered cells from attachment to the wells. In vivo treatment with Biobarrier significantly reduced tumor growth at both sites of surgical trauma (P = 0.001 and 0.015) and other non-traumatized intraperitoneal sites (P = 0.021).

Conclusions

Biobarrier maybe effective in reducing intra-abdominal tumor cell implantation with subsequent tumor development in conjunction with peritoneal trauma in a syngeneic rat model.     

Comparison of surgical outcomes between papillary thyroid cancer patients treated with the Harmonic ACE scalpel and LigaSure Precise instrument during conventional thyroidectomy: a single-blind prospective randomized controlled trial

Background

The aim of this study was to evaluate the safety and efficacy of thyroidectomy using the Harmonic ACE scalpel (HS) or the LigaSure Precise (LS) instrument in conventional thyroidectomy.

Materials and methods

A prospective, randomized controlled trial was performed. Between August 2011 and June 2012, 832 patients who required thyroidectomy for papillary thyroid cancer were randomized into groups treated with either the HS or the LS instrument. Operative time and surgical morbidities were analyzed.

Results

A total of 320 patients (HS group, N = 164; LS instrument group, N = 156) were randomized for analysis according to the intention-to-treat principle. There were no statistically significant differences in the operative times (HS group versus LS instrument group: 71.93 ± 18.26 versus 75.15 ± 20.13; P = 0.423), postoperative transient hypoparathyroidism (13.4% versus 14.1%; P = 0.858), and permanent recurrent laryngeal nerve injuries between the two groups.

Conclusions

In this study, both hemostatic devices were safe and effective in terms of postoperative results and complications without any differences.     

Inhibition of AAA in a rat model by treatment with ACEI perindopril

Background

The purpose of the present study was to evaluate the effect of a new angiotensin converting enzyme inhibitor perindopril on the formation of experimental abdominal aortic aneurysms (AAAs) in a rat model induced by intraluminal elastase infusion and extraluminal calcium chloride (CaCl₂) application.

Materials and methods

Thirty-six male Sprague–Dawley rats were randomly distributed into three groups (n = 12 per group): model (A), sham (B), and perindopril (C). Rats in model and perindopril groups underwent intra-aortic elastase perfusion and extraluminal CaCl₂ application to induce AAAs. Rats in the sham group received aortic perfusion and extraluminal application of saline. A dose of 3 mg/kg/d of perindopril was fed orally in the perindopril group. The maximum abdominal aortic diameter was measured in vivo on days 0 and 28 and by ultrasound on days 7, 14, and 21. The arterial blood pressure was measured directly using a pressure transducer after cannulation in surgery and before death. AAA tissue samples were harvested at day 28 and evaluated using normal hematoxylin and eosin stain, Verhoeff-van Gieson stain for elastin, and image analysis technique.

Results

Aortic diameters of rats in the model group consistently increased within 28 d, coinciding with the development of a transmural inflammatory response, thickening of intima, and destruction of the elastic media. Without alteration in blood pressure, the AAA formation rate and mean maximal diameter of aorta at day 28 were significantly lower in the perindopril group compared with the control group (1.71 ± 0.20 versus 2.70 ± 0.69 mm, P < 0.001; 0% versus 90.91%, P < 0.001) and were similar to those in the sham group (1.79 ± 0.29 mm, P = 0.175; 0%, P = 1). The thickness of intima in the perindopril group was lower than that in the model group (20.68 ± 9.96 versus 58.49 ± 32.01 μm, P = 0.001), but higher than that in the sham group (7.23 ± 2.68 μm, P = 0.005). The intensity of elastin fiber showed the opposite trend (0.8541 ± 0.0495 in sham group versus 0.7376 ± 0.1024 in perindopril group versus 0.5413 ± 0.0912 in model group, P < 0.001).

Conclusions

Perindopril inhibited the aortic degeneration and AAA formation in the experimental AAA model induced by elastase and CaCl₂. This effect, which was independent of its influence on hemodynamics, appeared to be induced by the suppression of the inflammatory cell influx and intimal thickening and the preservation of aortic medial elastin.     

Suppressive effects of fisetin on mice T lymphocytes in vitro and in vivo

Background

Most of the immunosuppressive drugs have satisfactory therapeutic effects on organ transplantation and autoimmune disease. However, their clinical application is limited by side effects. Therefore, new and safe immunosuppressive drugs against acute and chronic rejections are eagerly awaited. Fisetin, a flavonoid present in various types of vegetables and fruits, has few side effects and low level of toxicity, which would be a desirable clinical feature. In the present study, we investigated the immunosuppressive effects and underlying mechanisms of fisetin against T-cell activation in vitro and in vivo.

Methods

We measured the effect of fisetin on T-lymphocyte proliferation, T-cell subsets, cell cycle progression, cytokine production, and nuclear factor activation in vitro, as well as its influence on T cell–mediated delayed-type hypersensitivity reaction in vivo.

Results

In vitro, the results showed that fisetin significantly suppressed mouse splenocytes proliferation, Th1 and Th2 cytokine production, cell cycle and the ratio of CD4⁺/CD8⁺ T cells. Furthermore, fisetin exerts an immunosuppressive effect in mouse T lymphocytes through the suppression of nuclear factor kappa B activation and nuclear factor of activated T cells signaling in a dose-dependent manner. In vivo, fisetin treatment also significantly inhibited the dinitrofluorobenzene-induced delayed-type hypersensitivity reactions in mice.

Conclusions

Fisetin had strong immunosuppressive activity in vitro and in vivo, suggesting a potential role for fisetin as an immunosuppressive agent.     

Conversion to Mycophenolate Mofetil From Azathioprine Shows Significant Positive Effect on Graft Function in Long-Term Past–Kidney Transplantation Stable-State Patients

Objectives

A number of reports have shown that the efficacy of mycophenolate mofetil (MMF) is superior to that of azathioprine (AZP) for long-term kidney allograft survival. We conducted a retrospective single-center study to evaluate renal function more than 2 years after conversion from AZP to MMF in kidney transplant recipients several years after transplantation.

Methods

AZP was converted to MMF in 51 recipients at 17.0 ± 0.8 years after kidney transplantation who were followed up for more than 2 years after conversion. Estimated glomerular filtration rate (eGFR) was determined using the Formula of the Japanese Society of Nephrology.

Results

The eGFR was significantly greater at 1 year before conversion (41.72 ± 1.91 mL/min/1.73 m²) as compared with the day of conversion (39.04 ± 1.82 mL/min/1.73 m²; P < .05). After conversion, eGFR plateaued to 39.30 ± 2.01 mL/min/1.73 m² at 1 year and 38.24 ± 2.42 mL/min/1.73 m² at 2 years after conversion. The average eGFR slopes were −2.96 ± 0.36 mL/min/1.73 m² per year for AZP and 1.22 ± 0.10 mL/min/1.73 m² per year for MMF (P < .0001). Cyclosporine (CSA) was reduced from 176 ± 9.3 to 165 ± 9.8 mg/d (P = .0394) after the switch, whereas the CSA trough level was increased from 77.3 ± 6.6 to 118 ± 9.8 ng/mL (P = .0017). Furthermore, the daily dose of tacrolimus (TAC) was decreased from 3.5 ± 0.3 to 3.1 ± 0.3 mg/d (P = .0083).

Conclusions

Our findings demonstrated the safety of conversion from AZP to MMF even in the patients who underwent renal transplantation several years prior. In addition, these short-term results indicated the improvement in allograft function following conversion.     

Short-term physical inactivity impairs vascular function

Background

Sedentarism, also termed physical inactivity, is an independent risk factor for cardiovascular diseases. Mechanisms thought to be involved include insulin resistance, dyslipidemia, hypertension, and increased inflammation. It is unknown whether changes in vascular and endothelial function also contribute to this excess risk. We hypothesized that short-term exposure to inactivity would lead to endothelial dysfunction, arterial stiffening, and increased vascular inflammation.

Methods

Five healthy subjects (four men and one woman) underwent 5 d of bed rest (BR) to simulate inactivity. Measurements of vascular function (flow-mediated vasodilation to evaluate endothelial function; applanation tonometry to assess arterial resistance), inflammation, and metabolism were made before BR, daily during BR, and 2 d after BR recovery period. Subjects maintained an isocaloric diet throughout.

Results

BR led to significant decreases in brachial artery and femoral artery flow-mediated vasodilation (brachial: 11 ± 3% pre-BR versus 9 ± 2% end-BR, P = 0.04; femoral: 4 ± 1% versus 2 ± 1%, P = 0.04). The central augmentation index increased with BR (−4 ± 9% versus 5 ± 11%, P = 0.03). Diastolic blood pressure increased (58 ± 7 mm Hg versus 62 ± 7 mm Hg, P = 0.02), whereas neither systolic blood pressure nor heart rate changed. 15-Hydroxyeicosatetraenoic acid, an arachidonic acid metabolite, increased but the other inflammatory and metabolic biomarkers were unchanged.

Conclusions

Our findings show that acute exposure to sedentarism results in decreased endothelial function, arterial stiffening, increased diastolic blood pressure, and an increase in 15-hydroxyeicosatetraenoic acid. We speculate that inactivity promotes a vascular “deconditioning” state characterized by impaired endothelial function, leading to arterial stiffness and increased arterial tone. Although physiologically significant, the underlying mechanisms and clinical relevance of these findings need to be further explored.     

Percutaneous valved stent implantation in the ascending aorta for the treatment of very high-risk aortic regurgitation: an animal study

Purpose

We investigated the effects of percutaneous valved stent implantation in the ascending aorta as an alternative treatment for aortic regurgitation in a canine model.

Materials and methods

A total of 16 healthy dogs weighing an average of 18.3 ± 2.1 kg were used for the establishment of animal models of chronic aortic regurgitation by percutaneous aortic valve perforation and balloon dilation. At 2 mo after successful model establishment, all experimental animals underwent valved stent implantation in the ascending aorta and then were followed up for 3 mo.

Results

Experimental models of chronic aortic regurgitation were successfully established in 10 dogs. Surviving dogs underwent successful valved stent implantation in the ascending aorta and were subsequently followed up for 3 mo. The level of instantaneous aortic regurgitation at 3-mo follow-up was significantly reduced compared with that before valved stent implantation (2.4 ± 0.9 versus 10.6 ± 2.1 mL/s, P < 0.05). The left ventricular ejection fraction was significantly increased (53.8 ± 4.2% versus 37.8 ± 3.7%, P < 0.05), and the left ventricular end-diastolic volume was also significantly reduced (30.3 ± 2.2 versus 40.1 ± 3.6 mL, P < 0.05). No paravalvular leak, stroke, atrioventricular block, or other complications occurred in dogs undergoing valved stent implantation.

Conclusions

Percutaneous valved stent implantation in the ascending aorta is feasible, effective, and safe as an alternative treatment for very high-risk aortic regurgitation in a canine model.     

Docosahexaenoic acid,G protein–coupled receptors,and melanoma: is G protein–coupled receptor 40 a potential therapeutic target?

Background

To determine the effect of docosahexaenoic acid (DHA) on the growth of human melanoma in vitro and in vivo and to better understand the potential role of the G protein–coupled receptors (GPRs) in mediating this effect.

Materials and methods

For in vitro studies, human melanoma and control fibroblast cells were treated with DHA and TAK-875 (selective GPR40 agonist) and a cell viability assay was performed to determine cell counts. A murine subcutaneous xenograft model of human melanoma was used to test the effect of dietary treatment with an omega-3 fatty acid (FA) rich diet compared with an omega-6 FA rich diet on the growth of human melanoma in vivo. A similar animal model was used to test the effect of oral TAK-875 on the growth of established melanoma tumors in vivo.

Results

DHA has an inhibitory effect on the growth of human melanoma both in vitro and in vivo. Tumors from animals on the omega-3 FA rich diet were 69% smaller in weight (P = 0.005) and 76% smaller in volume compared with tumors from animals on the omega-6 FA rich diet. TAK-875 has an inhibitory effect on the growth of human melanoma both in vitro and in vivo. Tumors from animals treated with TAK-875 were 46% smaller in weight (P = 0.07), 62% smaller in volume (P = 0.03), and grew 77% slower (P = 0.04) compared with the placebo group.

Conclusions

DHA and TAK-875 have a profound and selective inhibitory effect on the growth of human melanoma both in vitro and in vivo.     

In vivo leukocyte-mediated brain microcirculatory inflammation: a comparison of osmotherapies and progesterone in severe traumatic brain injury

Background

Mannitol, hypertonic saline, and progesterone may blunt leukocyte recruitment after traumatic brain injury (TBI). We hypothesized that progesterone reduces pericontusional recruitment of leukocytes to a greater extent than either osmotherapy a day after TBI.

Methods

CD1 mice underwent controlled cortical impact and were treated with osmotherapy (mannitol and hypertonic saline) or progesterone. Thirty-two hours after TBI, live pial microscopy was used to evaluate leukocyte–endothelial interactions and immunohistochemistry was used for the detection of pericontusional tissue polymorphonuclear neutrophils. Neurologic recovery was assessed before sacrifice.

Results

Mannitol resulted in the lowest in vivo leukocyte recruitment compared with progesterone (795 ± 282 vs 1,636 ± 434 LEU/100 μm/minutes, P < .05). Mannitol also displayed lower tissue accumulation of leukocytes as compared with progesterone (5.7 ± 1.7 vs 15.2 ± .1 LEU/mm², P = .03). However, progesterone resulted in better neurologic recovery than either osmotherapy.

Conclusions

Leukocyte recruitment to injured brain is lowest with mannitol administration. How different agents alter progression of secondary brain injury will require further evaluation in humans.     

Monocyte activity is linked with abdominal aortic aneurysm diameter

Background

Systemic inflammation and increased matrix metalloproteinase (MMP) cause elastin degradation leading to abdominal aortic aneurysm (AAA) expansion. Several prospective studies report that statin therapy can reduce AAA expansion through anti-inflammation. We hypothesize that monocyte activity plays a pivotal role in this AAA development and this study examines patient peripheral blood monocyte cell adhesion, transendothelial migration, and MMP concentrations between AAA and non-AAA patients.

Materials and methods

Peripheral blood was collected and monocytes isolated from control (n = 15) and AAA (n = 13) patients. Monocyte adhesion, transmigration, and permeability assays were assessed. Luminex assays determined MMP-9 and tissue inhibitor of metalloproteinase-4 (TIMP-4) concentrations from cell culture supernatant and patient serum.

Results

AAA patient monocytes showed increased adhesion to the endothelium relative fluorescence units (RFU, 0.33 ± 0.17) versus controls (RFU, 0.13 ± 0.04; P = 0.005). Monocyte transmigration was also increased in AAA patients (RFU, 0.33 ± 0.11) compared with controls (RFU, 0.25 ± 0.04, P = 0.01). Greater numbers of adhesive (R² = 0.66) and transmigratory (R² = 0.86) monocytes were directly proportional to the AAA diameter. Significantly higher serum levels of MMP-9 (2149.14 ± 947 pg/mL) were found in AAA patients compared with controls (1189.2 ± 293; P = 0.01). TIMP-4 concentrations were significantly lower in AAA patients (826.7 ± 100 pg/mL) compared with controls (1233 ± 222 pg/mL; P = 0.02). Cell culture supernatant concentrations of MMP and TIMP from cocultures were higher than monocyte-only cultures.

Conclusions

Monocytes from AAA patients have greater adhesion and transmigration through the endothelium in vitro, leading to elevated MMP-9 levels and the appropriate decrease in TIMP-4 levels. The ability to modulate monocyte activity may lead to novel medical therapies to decrease AAA expansion.     

Clinical outcomes following bowel resection versus reduction of intussusception

Background

Intussusception is most commonly managed with air-contrast reduction. However, when this fails, emergent operation with resection or manual reduction is indicated. It is not known if there are advantages to resection compared with manual reduction.

Methods

A retrospective review of all patients receiving operative care for intussusception from February 2000 to December 2011. Patients undergoing intestinal resection were compared with those treated with manual reduction alone.

Results

Of 111 patients, 49 underwent resection and 62 underwent manual reduction. Mean (±SD) time to oral intake favored manual reduction (2.1 ± 1.2 versus 2.6 ± 1.2 d, respectively, P = 0.05). Manual reduction was associated with a greater need for repeat imaging (47% versus 18%, P = 0.002) and the only recurrences were with manual reduction (8% versus 0%, P = 0.1). Mean duration of stay was no different (P = 0.36), nor was the need for reoperation (P = 0.9).

Conclusions

Patients undergoing manual reduction have an increased number of radiographic imaging procedures. The surgeon should have a low threshold for resection for intussusceptions requiring operative management.     

Levobupivacaine inhibits lipopolysaccharide-induced high mobility group box 1 release in vitro and in vivo

Background

The aim of the study was to investigate whether levobupivacaine (LB) suppressed lipopolysaccharide (LPS)-induced high mobility group box 1 (HMGB1) release in vitro and in vivo, and to determin its molecular mechanisms of action.

Materials and methods

RAW264.7 cells were treated with LPS and LB for 24 h. Levels of HMGB1, nuclear factor-kappa B (NF-κB) and phosphorylated p38 mitogen-activated protein kinase (MAPK) were measured by Enzyme-linked immunosorbent assay and Western blotting; the levels of HMGB1 messenger RNA were measured by real-time polymerase chain reaction. In addition, cecal ligation and puncture–induced septic C57BL/6 received LB infusion, and the levels of HMGB1 and functional parameters of multiple organs determined using several detection kits.

Results

LB inhibited HMGB1 release in vitro and in vivo. Furthermore, LB inhibited the translocation of NF-κB and phosphorylation of p38 MAPK in vitro. Mice treated with LB infusion improved survival in mice and significantly reduced cecal ligation and puncture–induced dysfunction of organs.

Conclusions

LB suppresses LPS-induced HMGB1 release in vitro and in vivo by partially inhibiting NF-κB/p38 MAPK pathways. LB can rescue mice from sepsis and protect against organ dysfunction in septic mice.     

The effect of metallic tracheal stents on radiation dose in the airway and surrounding tissues

Background

Metallic airway stents are often used in the management of central airway malignancies. The presence of a metallic foreign body may affect radiation dose in tissue. We studied the effect of a metallic airway stent on radiation dose delivery in a phantom and an in vivo porcine model.

Methods

A metallic tracheal stent was fitted onto a support in a water phantom. Point dosimeters were positioned in the phantom around the support and the stent. Irradiation was then performed on a linear accelerator with and without the stent. Metallic tracheal stents were deployed in the trachea of three pigs. Dosimeters were implanted in the tissues near (Group 1) and away (Group 2) from the stent. The pigs were then irradiated, and the dose perturbation factor was calculated by comparing the actual dose detected by the dosimeters versus the planned dose.

Results

The difference in the dose detected by the dosimeters and the planned dose ranged from 1.8% to 6.1% for the phantom with the stent and 0%–5.3% for the phantom without the stent. These values were largely within the manufacturer's specified error of 5%. No significant difference was observed in the dose perturbation factor for Group 1 and Group 2 dosimeters (0.836 ± 0.058 versus 0.877 ± 0.088, P = 0.220) in all the three pigs.

Conclusions

Metallic airway stents do not significantly affect radiation dose in the airway and surrounding tissues in a phantom and porcine model. Radiation treatment planning systems can account for the presence of the stent. External beam radiation can be delivered without concern for significant dose perturbation.