Resistance index determination in the pre and post kidney transplantation time points in graft dysfunction diagnosis

BACKGROUND

Donor shortage necessitates the development of tools capable of objectively assessing kidney graft quality from expanded criteria donors and kidneys donated after cardiac death. The deteriorating donor profile is leading to a shift from cold storage toward machine perfusion preservation. Several authors found that renal resistance (RR) at the end of machine perfusion was an independent risk factor for the development of delayed graft function (DGF). In contrast, Doppler ultrasonography in the posttransplant period reveals renal hemodynamics and is useful in diagnosing renal allograft dysfunction. We sought to determine concordance between RR and the resistance index (RI) and their diagnostic value in the assessment of graft viability.

METHODS

RR was determined at the end of perfusion during hypothermic machine preservation and RI was measured by Doppler ultrasonography in the early posttransplant period. Agreement between these 2 measures was established by means of the intraclass correlation coefficient (ICC). Diagnostic validity for RR and RI was determined by sensitivity, specificity and positive and negative predictive values.

RESULTS

The ICC was 0.135, which indicates a slight agreement. RR and RI had limited value in the prediction of DGF for a specific kidney as reflected by a c-statistic of 0.58 and 0.66, respectively.

CONCLUSIONS

There is no agreement between the RR and RI, which may be owing to the different conditions under which measurements are made. The poor predictive power of RR for DGF indicates that kidneys should not be discarded based on RR criteria alone.

Machine perfusion: initial results in an expanded criteria donor kidney transplant program

BACKGROUND

Delayed graft function (DGF) negatively impacts graft survival. Expanded criteria donors (ECD) show a higher rate of DGF. Hypothermic machine perfusion (HMP) has shown a DGF decrease and an increase of survival at 1 year. Several authors found that renal resistance (RR) at the end of machine perfusion was an independent risk factor for the development of DGF and poorer graft survival. The objective of this study was to analyze HMP results in the context of an ECD program and assess the impact of donor parameters and resistance index (RI) during perfusion in graft survival after kidney transplantation.

METHODS

Donor age, terminal creatinine, machine perfusion time, percentage of glomerulosclerosis, and RI at the end of the perfusion were considered as risk predictors. Univariate and multivariate Cox regression analysis was constructed to find independent risk factors of DGF. Finally, diagnostic validity for RR was determined by sensitivity, specificity, and positive and negative predictive values.

RESULTS

Twenty-three percent of patients developed DGF. We found no difference in the ability of flow or RI to predict the development of DGF. The predictive accuracy of RI for DGF by receiver operator characteristic curve was poor, with a c-statistic of 0.66 (95% CI, 0.50-0.81; P = .046). Our analysis did not identify risk factors that predicted graft survival at 1 year. Patient and graft survival were 98.8% and 89.7%, respectively.

CONCLUSIONS

HMP has reduced the rate of DGF in our cohort of recipients of ECD grafts compared with historical data (23.3% vs 38.0%). Analysis did not identify risk pretransplant factors for graft survival at 1 year.

Impaired cardiac mitochondrial function and contractile reserve following an acute exposure to environmental particulate matter

BACKGROUND

It has been suggested that mitochondrial function plays a central role in cardiovascular diseases associated with particulate matter inhalation. The aim of this study was to evaluate this hypothesis, with focus on cardiac O2 and energetic metabolism, and its impact over cardiac contractility.

METHODS

Swiss mice were intranasally instilled with either residual oil fly ash (ROFA) (1.0 mg/kg body weight) or saline solution. After 1, 3 or 5 h of exposure, O2 consumption was evaluated in heart tissue samples. Mitochondrial respiration, respiratory chain complexes activity, membrane potential and ATP content and production rate were assessed in isolated mitochondria. Cardiac contractile reserve was evaluated according to the Langendorff technique.

RESULTS

Three hours after ROFA exposure, tissue O2 consumption was significantly decreased by 35% (from 1180 +/- 70 to 760 +/- 60 ng-at O/min g tissue), as well as mitochondrial rest (state 4) and active (state 3) respiration, by 30 and 24%, respectively (control state 4: 88 +/- 5 ng-at O/min mg protein; state 3: 240 +/- 20 ng-at O/min mg protein). These findings were associated with decreased complex II activity, mitochondrial depolarization and deficient ATP production. Even though basal contractility was not modified (control: 75 +/- 5 mm Hg), isolated perfused hearts failed to properly respond to isoproterenol in ROFA-exposed mice. Tissue O2 consumption rates positively correlated with cardiac contractile state in controls (r2 = 0.8271), but not in treated mice (r2 = 0.1396).

GENERAL SIGNIFICANCE

The present results show an impaired mitochondrial function associated with deficient cardiac contractility, which could represent an early cardiovascular alteration after the exposure to environmental particulate matter.

MYC antagonizes the differentiation induced by imatinib in chronic myeloid leukemia cells through downregulation of p27(KIP1.)

Chronic myeloid leukemia (CML) progresses from a chronic to a blastic phase where the leukemic cells are proliferative and undifferentiated. The CML is nowadays successfully treated with BCR-ABL kinase inhibitors as imatinib and dasatinib. In the CML-derived K562 cell line, low concentrations of imatinib induce proliferative arrest and erythroid differentiation. We found that imatinib upregulated the cell cycle inhibitor p27(KIP1) (p27) in a time- and -concentration dependent manner, and that the extent of imatinib-mediated differentiation was severely decreased in cells with depleted p27. MYC (c-Myc) is a transcription factor frequently deregulated in human cancer. MYC is overexpressed in untreated CML and is associated to poor response to imatinib. Using K562 sublines with conditional MYC expression (induced by Zn(2+) or activated by 4-hydroxy-tamoxifen) we show that MYC prevented the erythroid differentiation induced by imatinib and dasatinib. The differentiation inhibition is not due to increased proliferation of MYC-expressing clones or enhanced apoptosis of differentiated cells. As p27 overexpression is reported to induce erythroid differentiation in K562, we explored the effect of MYC on imatinib-dependent induction of p27. We show that MYC abrogated the imatinib-induced upregulation of p27 concomitantly with the differentiation inhibition, suggesting that MYC inhibits differentiation by antagonizing the imatinib-mediated upregulation of p27. This effect occurs mainly by p27 protein destabilization. This was in part due to MYC-dependent induction of SKP2, a component of the ubiquitin ligase complex that targets p27 for degradation. The results suggest that, although MYC deregulation does not directly confer resistance to imatinib, it might be a factor that contributes to progression of CML through the inhibition of differentiation.

Potentiality of standardized extract and isolated flavonoids from Zuccagnia punctata for the treatment of respiratory infections by Streptococcus pneumoniae: in vitro and in vivo studies

ETHNOPHARMACOLOGICAL RELEVANCE

Zuccagnia punctata Cav. (Fabaceae) is a monotypic species distributed in western Argentina and is traditionally used for the treatment of bacterial and fungal infections. The aim of this study was to demonstrated the antibacterial activity of the Zuccagnia punctata standardized extract and the structurally related non-methoxylated flavonoids with similar pattern of substitution and differences in ring C present in this plant species: 7-hydroxyflavanone (HF), 2',4'-dihydroxychalcone (DHC) and 3,7-dihydroxyflavone (DHF), against Streptococcus pneumoniae clinical isolates using in vitro and in vivo models.

MATERIALS AND METHODS

MIC values of natural products were determined by agar macrodilution method. In vivo activities were investigated in a Streptococcus pneumoniae infection model in mice. Lung and blood samples were obtained for bacterial cell counts. The serum was used by biochemical analysis (alanine transaminase, aspartate transaminase, urea and creatinine) in order to evaluate the toxicity of natural products.

RESULTS

All samples showed antimicrobial activity in vitro with MIC values between 50 and 500μg/ml. Zuccagnia punctata extract (1mg/mice) and HF (1mg/mice) significantly reduced the number of viable Streptococcus pneumoniae in lung (p<0.01) while lower quantities has not effect. Therefore, the present study has shown that intake once or twice a day of 1mg of Zuccagnia punctata extract or HF for seven days did not result in toxicity.

CONCLUSIONS

Our results showed that Zuccagnia punctata extract as well as one of its isolated flavonoids, 7-hydroxyflavanone, could be useful for the development of a novel respiratory infections treatment.

Salicylic acid negatively affects the response to salt stress in pea plants

We studied the effect of salicylic acid (SA) treatment on the response of pea plants to salinity. Sodium chloride (NaCl)-induced damage to leaves was increased by SA, which was correlated with a reduction in plant growth. The content of reduced ascorbate and glutathione in leaves of salt-treated plants increased in response to SA, although accumulation of the respective oxidised forms occurred. An increase in hydrogen peroxide also occurred in leaves of salt-exposed plants treated with SA. In the absence of NaCl, SA increased ascorbate peroxidase (APX; 100 μm) and glutathione-S transferase (GST; 50 μm) activities and increased catalase (CAT) activity in a concentration-dependent manner. Salinity decreased glutathione reductase (GR) activity, but increased GST and CAT activity. In salt-stressed plants, SA also produced changes in antioxidative enzymes: 100 μm SA decreased APX but increased GST. Finally, a concentration-dependent increase in superoxide dismutase (SOD) activity was induced by SA treatment in salt-stressed plants. Induction of PR-1b was observed in NaCl-stressed plants treated with SA. The treatment with SA, as well as the interaction between salinity and SA treatment, had a significant effect on PsMAPK3 expression. The expression of PsMAPK3 was not altered by 70 mm NaCl, but was statistically higher in the absence than in the presence of SA. Overall, the results show that SA treatment negatively affected the response of pea plants to NaCl, and this response correlated with an imbalance in antioxidant metabolism. The data also show that SA treatment could enhance the resistance of salt-stressed plants to possible opportunistic pathogen attack, as suggested by increased PR-1b gene expression.

[Peritoneal strumosis: an extension study with (99m)Tc-pertecnectate]

We report the case of a 35-year-old nulliparous woman, with a previous history of ovarian cystectomy diagnosed 3 years earlier due a struma ovarii type of monodermal teratoma in the right ovary and a hemorrhagic cyst in the left ovary. Progressive growth of the left adnexal mass was observed in the periodic medical check-ups. Due to this, a second laparoscopy was performed and, based on the findings, a left ovarian cystectomy, right salpingectomy and resection of multiple peritoneal implants were carried out. The pathology diagnosis was left struma ovarii and peritoneal strumosis. A whole body and SPECT/CT scan with (99m)Tc-pertechnetate was performed to detect possible peritoneal implants. This study helped to make the therapeutic decision.

Neoadjuvant bevacizumab treatment for colorectal liver metastasis: A retrospective study

613

Background: Patients with colorectal cancer (CRC) and liver metastases have a poor prognosis and may benefit from perioperative chemotherapy and disease resection. Bevacizumab is proven to improve outcomes in patients with metastatic CRC.

Methods: This is a retrospective chart review performed in colorectal patients with liver metastases. All the patients were > 18 years old and have undergone bevacizumab therapy as neoadjuvant treatment.

Results: 20 patients were analyzed. Baseline characteristics: median age 54.8 (49.2-65.8) years; male 45%; ECOG 0/1 40%/60%, 13 patients had metastatic disease at the time of their initial diagnosis. Median time from diagnosis of metastasis to surgery was 7.1 (5.4-9.6) months. Primary tumour locations were rectum (21.4%), colon (64.3%) and colon and rectum (14.3%). 80% and 20% of the patients received one and two lines of treatment before surgery, respectively. Mean cycles were 7.3±3.4 and 3.5±1.8 in first and second line, respectively. In 95% of the patients resection was curative. Mean number of resected metastasis was 3.4±2.8. 90%·of the patients achieved complete resection (R0) and 10% incomplete resection (R1). All the synchronous primary tumours (15) were resected. Among 16 valuable patients for pathological response, 1 (6.3%) experienced a pCR, 11 (68.8%) major response and 4 (25%) minor response. The median DFS was 12.2 months. The median OS was 48.9 months. Only one patient experienced grade 3-4 toxicity (rectal haemorraghe). Most frequent surgical complications were anastomotic filtration (8.7%) and wound infection (8.7%). Most frequent hepatic toxicities after surgery were steatohepatitis (25%) and sinusoidal dilatation (20%).

Conclusions: These data provide evidence that neoadjuvant chemotherapy including bevacizumab can be safely administered in patients with mCRC.

No significant financial relationships to disclose.

Safety and efficacy of first-line XELIRI with or without bevacizumab in patients with metastatic colorectal cancer: Analysis of two phase II studies

560

Background: The safety and efficacy of first-line XELIRI (capecitabine in combination with irinotecan) and XELIRI plus bevacizumab (BEV) have been evaluated in patients with metastatic colorectal cancer (mCRC). To date, however, no randomized studies comparing these regimens have been performed. This retrospective analysis compared efficacy and safety data for the two regimens from separate phase II studies performed at a single institution.

Methods: Patients with histologically documented metastatic or recurrent CRC and no prior treatment for advanced disease received irinotecan 175 mg/m2 on day 1 and oral capecitabine 1,000 mg/m2 twice daily on days 2-8 every 2 weeks (XELIRI study). For patients age ≥65 years, the starting doses of irinotecan and capecitabine were reduced to 140 mg/m2 and 750 mg/m2, respectively. In the second study, patients received the same regimen plus BEV 5 mg/kg on day 1 (XELIRI + BEV study).

Results: A total of 53 and 46 patients were entered into the XELIRI and XELIRI + BEV studies, respectively. Patient characteristics were generally similar in both groups. Efficacy results for the ITT populations are summarized in the Table. Patients treated with XELIRI + BEV had a significantly higher ORR and longer median TTP vs. XELIRI alone and a numerically longer median OS was observed (p=NS). The overall incidence of adverse events (all grades or grade 3/4) was similar in the two groups, although alopecia, mucositis, hand–foot syndrome, and haemorrhage were more common with XELIRI + BEV vs. XELIRI alone (all p<0.05).

Conclusions: In this retrospective comparison of two studies, the addition of BEV to XELIRI appeared to improve outcome relative to XELIRI alone in the first-line treatment of patients with mCRC. The overall incidence of adverse events was similar in the two groups.

[Table: see text]

No significant financial relationships to disclose.