Burkitt’s lymphoma variant of post-transplant lymphoproliferative disease (PTLD)

The occurrence of posttransplant lymphoproliferative disorder (PTLD) in solid organ allograft recipients can be quite varied in clinical presentation, histopathological characteristics and frequency. A variety of lymphomas can develop as a PTLD although some types appear infrequently and remain poorly understood in this clinical setting. In this report, we describe two cases of Burkitt s lymphoma presenting as a PTLD following liver transplantation. The recipients were 12 and 44 years of age and displayed gastrointestinal involvement by the tumors several years following transplant. The tumors displayed the typical histological features of Burkitt s lymphoma and were markedly positive for EBV. The tumors displayed similar immunophenotypic characteristics by flow cytometry and had rearrangements of the immunoglobulin J-H heavy chain. The tumors required aggressive chemotherapy and a cessation of immunosuppressive therapy. This report demonstrates that Burkitt s type lymphomas can develop in the posttransplant setting and that these tumors contain morphologic, cytofluorographic and molecular features identical to Burkitt s lymphomas that occur in non-transplant patients. Our experience is that these PTLD- Burkitt s lymphomas behave aggressively and require intensive chemotherapeutic intervention.     

Olfactory schwannoma

Olfactory schwannomas are very rare. For this reason they have never been diagnosed preoperatively. We report a case and describe the CT and MR imaging findings. Clinically, the young age of presentation, and radiologically the presence of bone scalloping, and the absence of both bone sclerosis and a dural tail, may help in the differential diagnosis of meningioma.     

Standard antireflux operations in patients who have Barrett's esophagus. Current results

Several therapeutic options exist for patients who have BE, and treatment should be individualized (Fig. 1). The best option in patients who have a high surgical risk or who reject surgery is lifelong conservative treatment, adjusting the PPI dosage with pH-metric controls. In patients who have a low surgical risk the best option is Nissen fundoplication. Only in cases in which esophageal shortening prevents a tension-free fundoplication from being done is a Collis gastroplasty associated with a fundoplication indicated. Other options may be indicated only in exceptional circumstances: (a) duodenal switch, when, after multiple failures with previous surgery, the approach to the esophagogastric junction is extremely difficult; and (b) esophageal resection, when there is a nondilatable esophageal stenosis and in cases in which the histologic study reveals the presence of high-grade dysplasia. Whatever treatment is used, an endoscopic surveillance program is mandatory, since, with the exception of total esophagectomy, no therapeutic option completely eliminates the risk for progression to adenocarcinoma.     

“The Tourist Season Goes Down But Not the Prices.” Tourism and Food Insecurity in Rural Costa Rica

Data from women in two communities in rural Costa Rica were analyzed in order to examine food insecurity in an area undergoing a shift from an agricultural economy to tourism (e.g., eco/adventure tourism). While there were significant differences in socio-economic status between the two communities, the prevalence of food insecurity was high in both, ranging from 67% in the agricultural community to 73% in the tourism community. Not being a member of a food cooperative (OR = 4.85), not having a working stove (OR = 6.27), and increasing body mass index (BMI) (OR = 1.32) predicted food insecurity in both communities. Additionally, the frequency of condiment use was inversely associated with food insecurity (OR = .363). These findings along with other data suggest that food insecurity is a problem in this area. Furthermore, dietary quality associated with food insecurity might be responsible for the high prevalence of obesity among the study participants.     

Reliability of the life chart schedule for assessment of the long-term course of schizophrenia

We report on the inter-rater reliability of the Life Chart Schedule (LCS). The LCS is designed to assess the long-term course of schizophrenia in four key domains (symptoms, treatment, residence, and work) over two time periods (past two years, entire period of illness). The subjects were 27 consecutive admissions to a schizophrenia research unit. The LCS was filled out by pairs of raters, blinded to each others' ratings, using the same data (interview with subject and chart). Reliability was examined for 45 LCS ratings selected from all four domains and both time periods. Selected ratings pertained to the duration of specified experiences, the quality of these experiences, and the long-term time trend. The kappa statistic and the intra-class correlation coefficient (ICC) were used to determine inter-rater reliability for continuous and categorical ratings, respectively. LCS ratings proved reliable in all four key domains and both time periods. The reliability was fair to excellent for ratings of duration of experience (ICC ranged from 0.53 to 0.99), quality of experience (kappa ranged from 0.46 to 0. 92) and long-term time trends (kappa ranged from 0.66 to 0.94). The LCS can be used to obtain reliable ratings of the long-term course of schizophrenia in multiple domains.     

Event-related brain potentials (ERPs) in schizophrenia for tonal and phonetic oddball tasks.

BACKGROUND: Prior studies using simple target detection ("oddball") tasks with pure tones have reported asymmetric reduction of the P3 event-related potential (ERP). This study investigated the time course and topography of ERPs recorded during both tonal and phonetic oddball tasks. METHODS: Event-related potentials of 66 patients (14 unmedicated) diagnosed with schizophrenia (n = 46) or schizoaffective disorder (n = 20) and 32 healthy adults were recorded from 30 scalp electrodes during two oddball tasks using consonant-vowel syllables or complex tones. Overlapping ERP components were identified and measured by covariance-based principal components analysis. RESULTS: Schizophrenic patients showed marked, task-independent reductions of early negative potentials (N1, N2) but not reduced P3 amplitude or abnormal P3 asymmetry. Task-related hemispheric asymmetries of the N2/P3 complex were similar in healthy adults and schizophrenic patients. Poorer task performance in patients was related to ERP amplitudes, but could not account for reductions of early negativities. CONCLUSIONS: The findings suggest that both patients and control subjects activated lateralized cortical networks required for pitch (right frontotemporal) and phoneme (left parietotemporal) discrimination. Task-independent reductions of negativities between 80 and 280 msec after stimulus onset suggest a deficit of automatic stimulus classification in schizophrenia, which may be partly compensated by later effortful processing.     

Interaction of mouse prolactin with mouse hepatic receptors

Lactogenic receptors are usually studied in heterologous systems where prolactin is derived from one species and receptors prepared from another. In such systems the foreign prolactin could be seen as a growth hormone by the host tissue. We have therefore developed a homologous radioreceptor assay using secreted mouse prolactin (smPRL) and mouse hepatic receptors. In this system, monovalent anions augment the smPRL-receptor interaction in the order F- greater than Cl- greater than Br- greater than I-. Divalent cations (Mg2+, Ca2+, Sr2+), phosphate and acetate also increase smPRL binding. Temperature and pH optima are at 8 degrees C and pH 8.3, respectively. Under optimum conditions, the percent total, specific and nonspecific binding are 55%, 45% and 10%, respectively. At infinite receptor concentration the maximum specific bindability of labeled smPRL is 50%. The effects of ions on binding of smPRL to the receptor show that hydrophobic forces participate in smPRL-receptor coupling. The biphasic dissociation kinetics show initial and final rate constants of 1.56 X 10(-4)/s and 7.62 X 10(-6)/s, respectively. The lactogenic receptor does not bind mouse growth hormone; however, it binds both mouse placental lactogen (mPL) and smPRL with equilibrium association constants of 3.90 X 10(8) M-1 and 2.25 X 10(8) M-1, respectively, suggesting that smPRL and mPL share biological roles by acting through the same receptor.     

Prognostic value of the epidermal growth factor receptor (EGRF) and p53 in advanced head and neck squamous cell carcinoma patients treated with induction chemotherapy

We measured the expression of the p53 nuclear protein and epidermal growth factor receptor (EGFR) in 46 biopsy samples from patients with advanced head and neck cancer treated with induction combination chemotherapy of 5-fluorouracil, cisplatin, and paclitaxel. Tumour expression of p53 protein was analysed with the monoclonal D07 antibody and EGFR with monoclonal H11 antibody. The overall response, defined as complete (CR) and partial response (PR) rates to treatment, was 88%. p53 positive staining was significantly more frequent in patients who did not respond to the induction treatment. EGFR expression failed to show any correlation with the response rate. Multivariate analysis indicated that a tumour location in the oral cavity together with p53 expression combined with moderate-to-high EGFR staining were independent prognostic factors of a shorter disease-free survival (DFS). Location of the tumour in the oral cavity and EGFR expression had independent prognostic value for overall survival (OS). We conclude that the EGFR status and an oral cavity location of the tumour have independent prognostic value in patients with advanced head and neck carcinoma treated with induction chemotherapy. The p53 status appears to be a determinant of the tumour chemo-sensitivity in advanced head and neck squamous cell carcinoma (HNSCC). The presence in the tumour of a p53-positive stain and moderate-to-high staining of EGFR is associated with a shorter DFS and time to treatment failure (TTF) probably reflecting a more aggressive tumour phenotype.