Clinical application of decellularized and lyophilized human amnion/chorion membrane grafts for closing post‐laryngectomy pharyngocutaneous fistulas

Background and Objectives

Squamous cell carcinoma is the most common pathological type among the cancers of the larynx. Standard treatment for squamous cell carcinoma of the larynx is the combination of chemotherapy, radiotherapy, and laryngectomy. Pharyngocutaneous fistula is a common complication of laryngectomy. We hypothesized that decellularized and lyophilized human amnion/chorion membrane can be an effective, non‐invasive method of treating pharyngocutaneous fistula.

Methods

A total of 67 patients with laryngeal squamous cell carcinoma were retrospectively analyzed after treatment in a prospective trial. After preoperative chemotherapy, radiotherapy, and total or extended laryngectomy, primary wound healing occurred in 42 (62.7%) patients. Pharyngocutaneous fistula developed in 8 (11.9%) patients. Decellularized and lyophilized human amnion/chorion membrane grafts were used to reconstruct the fistulas.

Results

The average time for the full healing of the wound in all patients after transplantation of these grafts was 18 days.

Conclusion

The advantages of using these grafts over other existing methods of pharyngocutaneous fistula treatment are that they are non‐invasive, prevent donor morbidity, and enable management of the wound without using classical wound gauze. J. Surg. Oncol. 2016;113:538–543. © 2016 The Authors. Journal of Surgical Oncology Published by Wiley Periodicals, Inc.     

EGFR gene gain and PTEN protein expression are favorable prognostic factors in patients with KRAS wild-type metastatic colorectal cancer treated with cetuximab

Introduction

Cetuximab is a monoclonal epidermal growth factor receptor (EGFR)-targeting antibody, used in the treatment of colon cancer. KRAS mutation status is strongly predictive of cetuximab efficacy, but more predictive factors are needed for better patient selection. PTEN is a downstream inhibitor of the EGFR pathway and has been evaluated as a predictive factor of cetuximab efficacy in colorectal cancer.

Patients and methods

Formalin-fixed paraffin-embedded tumor tissue samples were collected from 226 patients with advanced or metastatic colorectal cancer that had been treated with cetuximab. Clinical information was collected retrospectively from the patients’ medical records. After central evaluation, 147 cases with adequate material were eligible for further evaluation. EGFR and PTEN status was evaluated with immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Data were associated with cetuximab treatment outcome. Additional analysis was performed with previously published data on PIK3CA, BRAF and KRAS mutation status and EGFR ligand amphiregulin (AREG) and epiregulin intratumoral mRNA expression levels. PIK3CA mutation status and PTEN protein expression were also analyzed as a single complex parameter, to evaluate the predictive value of PI3K/PTEN axis dysfunction as one entity.

Results

Analysis showed a borderline association of overall response rate (ORR) and time to progression (TTP) with EGFR protein overexpression by IHC (p = 0.059 and p = 0.057, respectively) and a positive association of EGFR gain by FISH (found in only five cases) with longer TTP (p = 0.026). No association was found between ORR or TTP and PTEN IHC or FISH status. Comparative analysis with previously published data showed that PTEN protein expression is associated with longer TTP in patients with wild-type (WT) KRAS (p = 0.036) and especially in the ones with elevated AREG levels (p = 0.046), as well as in patients with both KRAS and BRAF WT (p = 0.019). Patients with both PIK3CA WT and PTEN protein expression had significantly longer TTP (p = 0.010) versus all others, in the absence of BRAF and KRAS mutations, a finding which persisted in the KRAS WT/AREG high subgroup (p = 0.046).

Conclusions

In this cetuximab-treated colorectal cancer population, EGFR gain was associated with better outcome and PTEN protein expression with longer TTP in KRAS WT, KRAS WT/AREG high and KRAS/BRAF WT subpopulations. Cetuximab efficacy is greater with intact and activated EGFR signaling, without activating mutations of KRAS/BRAF and in the presence of preserved PTEN inhibitory activity upon the PI3K/AKT pathway. These results reflect a solid biological rationale and warrant further evaluation of the predictive role of PTEN in prospective studies.     

Self-citations in six anaesthesia journals and their significance in determining the impact factor

Self-citation of a journal may affect its impact factor. We investigated self-citations in the 1995 and 1996 issues of six anaesthesia journals by calculating the self-citing and self-cited rates for each journal. Self-citing rate relates a journal's self- citations to its total number of references. We defined self-cited rate as the ratio of a journal's self-citations to the number of times it is cited by the six anaesthesia journals. We also correlated self-citing rates with the impact factor of the six journals for 1997. Citations among the six journals differed significantly (P < 0.0001). Anesthesiology had the highest self-citing rate (57%). Anaesthesia, Anesthesia and Analgesia, British Journal of Anaesthesia, Canadian Journal of Anaesthesia and the European Journal of Anaesthesiology had self-citing rates of 28%, 28%, 30%, 11% and 4% respectively. The self- cited rates were 31%, 35%, 34%, 27%, 31% and 17% for Anaesthesia, Anesthesiology, Anesthesia and Analgesia, British Journal of Anaesthesia, Canadian Journal of Anaesthesia and the European Journal of Anaesthesiology, respectively. North America journals cited the North America literature. This also occurred, to a lesser extent, in the European anaesthesia journals. A significant correlation between self-citing rates and impact factors was found (r = 0.899, P = 0.015). A high self-citing rate of a journal may positively affect its impact factor.      

Pharmacokinetics of hydroxyurea in plasma and cerebrospinal fluid of HIV-1-infected patients

Hydroxyurea has been shown to potentiate the activity of the antiretroviral nucleoside analogs. A significant complication of AIDS is invasion of the virus into the CNS, resulting in HIV-associated dementia (HAD). Because of the polar nature of these nucleosides and the presence of efflux pumps in the blood-brain barrier, only low CNS drug concentrations are achieved. Introduction of hydroxyurea into the CNS may therefore increase the antiviral activity of these drugs. This study evaluates the accessibility of hydroxyurea to the CNS following oral drug administration. Twelve HIV patients received 800 mg, 1000 mg, or 1200 mg oral hydroxyurea. Cerebrospinal fluid (CSF) and plasma drug concentrations were measured over 8 hours and simultaneously fitted to a pharmacokinetic model. It was determined that CSF hydroxyurea concentrations, corresponding to those found to increase antiretroviral nucleoside activity in vitro, were achieved.     

A comparison between a researcher-rated and a self-report method of insight assessment in chronic schizophrenia revisited: a replication study using the SUMD and SAIQ

Previous research in schizophrenia has not consistently found concurrent validity between researcher-rated and self-report scales of insight. Differences in the correlations between the two types of scales have been found when order of administration is varied. The current study sought to replicate this earlier study in a sample of 21 patients with chronic schizophrenia who were given the same researcher-rated scale (Scale to Assess Unawareness of Mental Disorder; SUMD) and a different self-report measure (Self-Appraisal of Illness Questionnaire; SAIQ). A counterbalanced research design was employed. Significant correlations (p < 0.05) were found between the SUMD and SAIQ subscales in the SAIQ first group but not in the SUMD first group. The present study replicated earlier findings and provides further support for the importance of order of administration effects when evaluating concurrent validity between different types of insight scales. The reliability of insight scales may be substantially improved if a self-report insight scale is administered prior to a researcher-rated scale.     

Autocrine adenosine signaling promotes regulatory T cell-mediated renal protection

Regulatory T cells (Tregs) suppress the innate inflammation associated with kidney ischemia-reperfusion injury (IRI), but the mechanism is not well understood. Tregs express CD73, the final enzyme involved in the production of extracellular adenosine, and activation of the adenosine 2A receptor (A(2A)R) on immune cells suppresses inflammation and preserves kidney function after IRI. We hypothesized that Treg-generated adenosine is required to block innate immune responses in kidney IRI and that the Treg-generated adenosine would signal through A(2A)Rs on inflammatory cells and, in an autocrine manner, on Tregs themselves. We found that adoptively transferred wild-type Tregs protected wild-type mice from kidney IRI, but the absence of adenosine generation (CD73-deficient Tregs) or adenosine responsiveness (A(2A)R-deficient Tregs) led to inhibition of Treg function. Pharmacologic stimulation of A(2A)R before adoptive transfer augmented the ability of wild-type and CD73-deficient Tregs to suppress kidney IRI. Microarray analysis and flow cytometry revealed that A(2A)R activation enhanced surface PD-1 expression on Tregs in the absence of any other activation signal. Treatment of Tregs with a PD-1 blocking antibody before adoptive transfer reversed their protective effects, even if pretreated with an A(2A)R agonist. Taken together, these results demonstrate that the simultaneous ability to generate and respond to adenosine is required for Tregs to suppress innate immune responses in IRI through a PD-1-dependent mechanism.     

3-methylindole-induced toxicity to human bronchial epithelial cell lines.

Transfected BEAS-2B cells that express different cytochrome P450 enzymes were used to assess whether human bronchial epithelial cell lines are target cells for 3-methylindole (3MI)-induced damage. Four different transfected BEAS-2B lines overexpressing P450s 2A6, 3A4, 2F1, and 2E1 (B-CMV2A6, B-CMV3A4, B-CMV2F1, and B-CMV2E1), respectively, were compared. The B-CMV2F1 and B-CMV3A4 cells were the most susceptible to 3MI-mediated cytotoxicity, measured by leakage of lactate dehydrogenase into the medium after a 48-h incubation. The toxicity was ameliorated by pretreatment with 1-aminobenzotriazole (ABT). Depletion of glutathione with diethylmaleate decreased the onset and increased the extent of cell death with 3MI. Thus, 3MI is cytotoxic to immortalized bronchial epithelial cells overexpressing 2F1 without concomitant depletion of GSH, but depletion of GSH modestly enhances the cytotoxicity of 3MI to human lung cells. Additional studies clearly demonstrated that a low concentration of 3MI (10 micro M) induced apoptosis in BEAS-2B cells that was measured by DNA fragmentation, and apoptosis was inhibited by the presence of ABT. The B-CMV2F1 cells overexpressing 2F1 demonstrated increased apoptosis (measured by Annexin-V binding) at 24 h with 100 micro M 3MI. Therefore, CYP2F1 in human bronchial epithelial lung cells may bioactivate 3MI to 3-methyleneindolenine, which induces programmed cell death at relatively low concentrations. Human lung cells may be susceptible to this prototypical pneumotoxicant.     

Evaluation of the cardiomyopathy in becker muscular dystrophy

To evaluate the features and the course of cardiomyopathy in Becker muscular dystrophy, 68 patients–identified by clinical assessment and by reduced dystrophin labeling and/or DNA analysis–were followed in the years 1976–1993, for periods ranging from 3 to 18 years (mean 8). Patients periodically underwent clinical, electrocardiographic, echocardiographic, nuclear, and radiological assessments. Preclinical cardiac involvement was found in 67.4% of patients under 16 years of age, decreasing to 30% in patients older than 40. Clinically evident cardiomyopathy was found in 15% of patients under 16 years of age, increasing to 73% in patients older than 40. A real, dilated cardiomyopathy is the most frequent type of myocardial involvement after the age of 20. Results show that the severity of cardiac involvement can be unrelated to the severity of skeletal muscle damage and confirm that cardiac dysfunction is a primary feature of Becker muscular dystrophy.© 1995 John Wiley &Sons, Inc.