Comparative analysis of the capacity of tombusvirus P22 and P19 proteins to function as avirulence determinants in Nicotiana species

We have used an agroinfiltration assay for a comparative study of the roles of tombusvirus P22 and P19 proteins in elicitation of hypersensitive response (HR)-like necrosis and the role of P19 in silencing suppression in Nicotiana species. The advantage of agroinfiltration rather than expression in plant virus vectors is that putative viral avirulence proteins can be evaluated in isolation, eliminating the possibility of synergistic effects with other viral proteins. We found that tombusvirus P22 and P19 proteins elicited HR-like necrosis in certain Nicotiana species but, also, that Nicotiana species could recognize subtle differences in sequence between these proteins. Furthermore, Nicotiana species that responded with systemic necrosis to virion inoculations responded to agroinfiltration of tombusvirus P19 with a very weak and delayed necrosis, indicating that the rapid HR-like necrosis was associated with putative resistance genes and a plant defense response that limited the spread of the virus. Tombusvirus P19 proteins also appeared to differ in their effectiveness as silencing suppressors; in our assay, the P19 proteins of Cymbidium ringspot virus and Tomato bushy stunt virus were stronger silencing suppressors than Cucumber necrosis virus P20. Finally, we show that agroinfiltration can be used to track the presence of putative plant resistance genes in Nicotiana species that target either tombusvirus P19 or P22.

Perfusion-based microfluidic device for three-dimensional dynamic primary human hepatocyte cell culture in the absence of biological or synthetic matrices or coagulants

We describe a perfusion-based microfluidic device for three-dimensional (3D) dynamic primary human hepatocyte cell culture. The microfluidic device was used to promote and maintain 3D tissue-like cellular morphology and cell-specific functionality of primary human hepatocytes by restoring membrane polarity and hepatocyte transport function in vitro without the addition of biological or synthetic matrices or coagulants. A unique feature of our dynamic cell culture device is the creation of a microenvironment, without the addition of biological or synthetic matrices or coagulants, that promotes the 3D organization of hepatocytes into cord-like structures that exhibit functional membrane polarity as evidenced by the expression of gap junctions and the formation of an extended, functionally active, bile canalicular network.

Diverse and newly recognized effects associated with short interfering RNA binding site modifications on the Tomato bushy stunt virus p19 silencing suppressor

The Tomato bushy stunt virus-encoded P19 forms dimers that bind duplex short interfering RNAs (siRNAs) to suppress RNA silencing. P19 is also involved in multiple host-specific activities, including the elicitation of symptoms, and in local and/or systemic spread. To study the correlation between those various roles and the siRNA binding by P19, predicted siRNA-interacting sites were modified. Twenty-two mutants were generated and inoculated onto Nicotiana benthamiana plants, to reveal that (i) they were all infectious, (ii) symptom differences did not correlate strictly with mutation-associated variation in P19 accumulation, and (iii) substitutions affecting a central domain of P19 generally exhibited symptoms more severe than for mutations affecting peripheral regions. Three mutants selected to represent separate phenotypic categories all displayed a substantially reduced ability to sequester siRNA. Consequently, these three mutants were compromised for systemic virus spread in P19-dependent hosts but had differential plant species-dependent effects on the symptom severity. One mutant in particular caused relatively exacerbated symptoms, exemplified by extensive morphological leaf deformations in N. benthamiana; this was especially remarkable because P19 was undetectable. Another striking feature of this mutant was that only within a few days after infection, viral RNA was cleared by silencing. One more original property was that host RNAs and proteins (notably, the P19-interactive Hin19 protein) were also susceptible to degradation in these infected N. benthamiana plants but not in spinach. In conclusion, even though siRNA binding by P19 is a key functional property, compromised siRNA sequestration can result in novel and diverse host-dependent properties.

On-chip microdialysis system with flow-through glucose sensing capabilities

BACKGROUND

Microdialysis is a sampling technique based on controlling the mass transfer rate of different-sized molecules across a semipermeable membrane. Because the dialysis process has minimal effects on the surrounding fluid, it is viewed as a tool for continuous monitoring of human metabolites. In diabetes treatment, microdialysis probes have been used as sampling systems coupled to a glucose biosensor but may struggle to obtain high recoveries of analytes, as the sampling housing, probes, and glucose sensors are fabricated as separate pieces and then assembled, resulting in a large dead volume, which limits sensing frequency. An in situ combination of a miniaturized microdialysis probe with an integrated glucose sensor could help solve some of these problems.

METHOD

The system was fabricated by bonding a 6-mum-thick polycarbonate track-etch membrane with 100-nm-diameter pores onto microfluidic channels with the electrochemical glucose sensing electrodes patterned within the microchannels.

RESULTS

In vitro experiments demonstrating glucose microdialysis with continuous sensing were conducted. The permeability of glucose to the polycarbonate membrane with a 100-nm-diameter pore size was obtained to be 5.44 mum/s. Glucose recovery of 99% was observed using this microdialysis system at a perfusion flow rate of 0.5 microl/min. Experiments monitoring fluctuating glucose concentrations in the time domain at 99% recovery were also performed. The lag time was measured to be 210 seconds with 45 seconds contributed by mass transfer limitations and the rest from dead volume within the experimental setup.

CONCLUSION

The electrochemical sensing component was able to continuously track concentration changes in the reservoir. This system is expected to have the proper sensitivity to track physiologically relevant concentration changes of glucose with a lag time of less than 1 minute and minimal amplitude reduction for continuous glucose monitoring for diabetes treatment.

Unusual pox lesions found in Chinese jungle mynahs (Acridotheres cristatellus)

Pox lesions involving feathered and unfeathered skin, the oral cavity and the uropygial gland were found in Chinese jungle mynahs. Characteristic intracytoplasmic inclusions were detected in the proliferative cells of all lesions. Ultrastructurally, the virus particles consisted of a convoluted outer membrane enclosing lateral bodies and a biconcave central core, typical for poxvirus. The nucleotide sequences of the amplicon obtained with a set of primers for the 4b core protein of fowl poxvirus revealed that the mynah poxvirus was phylogenetically related to wood pigeon poxvirus. This is the first report of poxvirus infection affecting the uropygial gland.

Components of an integrated microfluidic device for continuous glucose monitoring with responsive insulin delivery

Miniaturized medical diagnostic and treatment devices are currently being developed. Microneedles and miniaturized microdialysis systems are particularly well suited to impact diabetes treatment for continuous glucose monitoring and feedback-controlled insulin delivery. Microneedles are an attractive advanced drug delivery system used to mechanically penetrate the skin and inject insulin intradermally where it is rapidly absorbed by the capillary bed into the bloodstream. The real advantage of microneedle-enhanced drug delivery lies in the fact that drug is actively injected into a patient so the dosage may be varied with time to allow complex drug delivery profiles. The delivery is independent of the drug composition and merely relies on the subsequent drug absorption into the bloodstream. A miniaturized microdialysis probe for continuous glucose sensing has also been designed. Microdialysis is based upon controlling the mass transfer rate of glucose diffusing across a semipermeable membrane into a dialysis fluid while excluding larger molecules such as proteins. Polymer microdialysis membranes are integrated with microfluidic systems. Because of the high surface area to fluid volume ratio of miniaturized fluid channels, faster recovery of glucose to increase glucose sensing frequency is expected. This work highlights recent advances made in the design and fabrication of microneedles to make them more biocompatible and more fracture resistant in order to effectively enter the biomedical market. In addition, the design of a miniaturized microdialysis system for increased glucose sampling frequency is presented. The sensing and infusion technologies may be combined into a miniaturized "artificial pancreas" for minimally invasive feedback-controlled insulin delivery.

Delayed therapy with curative intent in a contemporary prostate cancer watchful-waiting cohort

OBJECTIVE

To identify predictors of delayed therapy with curative intent, an increasingly common option in contemporary patients with prostate cancer who initially choose watchful waiting.

PATIENTS AND METHODS

The characteristics of all patients at one institution and diagnosed with T1-4NXM0 prostate cancer between 1993 and 2000 were prospectively recorded. Factors recorded included: age, tumour stage, histological type, Gleason score, serum prostate specific antigen (PSA) level, prostate volume, PSA density (PSAD), percentage of positive biopsy cores, and the initial treatment selection. Outcomes, including all cancer-directed interventions, all serum PSA values, and initial outcomes of all interventions with curative intent, were determined by review of all medical records and cancer registry data.

RESULTS

Of 187 patients on watchful waiting, 175 had stage T1 or T2 cancer and were analysed primarily. Thirty-eight (22%) of these patients received delayed intervention with curative intent (15 radical prostatectomy, 17 external beam radiotherapy, six brachytherapy). Age (P < 0.001) and percentage of positive biopsy cores (P = 0.042) were significant independent predictors of intervention with curative intent. When the PSA doubling time was added to the model it became a significant predictor (P = 0.018), with percentage positive biopsy cores (P = 0.022) and age (P < 0.001).

CONCLUSIONS

Therapy with curative intent is common in contemporary patients with prostate cancer who initially choose watchful waiting. Age and percentage positive biopsy cores are independent predictors of such intervention, with PSA doubling time also an independent predictor.

Prediction of the distance from skin to epidural space for low-thoracic epidural catheter insertion by computed tomography

BACKGROUND

It may be clinically useful to predict the depth of the epidural space.

METHODS

To investigate the accuracy of preoperative abdominal computed tomography (CT) in prediction of the distance for low-thoracic epidural insertion, a single group observational study was conducted in 30 male patients undergoing elective major abdominal surgery requiring epidural analgesia for postoperative pain relief. Using the paramedian approach, low-thoracic epidural insertion at T10-11 interspace was performed with a standardized procedure to obtain an actual insertion length (AIL). According to the principles of trigonometry, an estimated insertion length (EIL) was calculated as 1.26 times the distance from skin to epidural space measured from the preoperative abdominal CT.

RESULTS

The mean (SD) EIL and AIL were 5.5 (0.7) and 5.1 (0.6) cm, respectively, with a significant correlation (r=0.899, P<0.01). The EIL tended to have a higher value than the AIL (0.4 (0.3) cm). There were significant correlations of both EIL and AIL with weight (P<0.01), BMI (P<0.01), and body fat percentage (P<0.01), but not with height (P>0.05).

CONCLUSIONS

We conclude that the preoperative abdominal CT is helpful in prediction of the distance for low-thoracic epidural insertion using the paramedian approach.

Clinical outcome in children with craniopharyngioma treated with primary surgery and radiotherapy deferred until relapse

BACKGROUND

To report the clinical outcome in children with craniopharyngioma following primary surgery and deferred radiotherapy at relapse.

PROCEDURE

Twenty-five children with craniopharyngioma were treated with primary surgery. Total resection was achieved in 19 children (76%), while in 24% total resection was not achieved due to tumor adhesion to adjacent critical structures. None of these children received radiation therapy immediately after total or sub-total resection. Radiotherapy was delivered at the time of relapse in 11 patients (44%).

RESULTS

The median follow-up from primary surgery was 10 years (3-16 years). The 14 year overall survival was 100%. Tumor recurrence was observed in (12/25) 48% at a median interval of 17 months. Tumor recurrence following total resection was 6/19 (32%) compared to 100% (6/6) following sub-total resection, and radiotherapy. The 2, 3, and 6 years relapse-free survival following initial surgery was 72, 55, and 50%, respectively. Univariate analysis revealed only extent of surgery to be significant for local recurrence (P < 0.0001). The sequelae observed in these patients included panhypopituitarism (100%), appetite disorders and hypothalamic obesity (32%), neuropsychological and behavioral disorders (20%), and sleep disorders (12%). Majority of children with non-endocrine complications had a local recurrence requiring further surgery and radiotherapy.

CONCLUSIONS

The two standard treatment options in children with craniopharyngioma are primary surgery and sub-total resection followed by radiotherapy. In certain subgroups of patients such as those with large tumors and hypothalamic extension, primary surgery is associated with a high incidence of complications and high failure rates. We recommend utilization of an individualized risk-based treatment approach, that attempts to maximize cure rates without compromising long-term functional outcome in children with craniopharyngiomas.

Clinical features of atypical Kawasaki disease

From 1989 through 1998, a total of 132 children admitted to the National Taiwan University Hospital were identified as having Kawasaki disease. Twenty (15%) of them did not meet the diagnostic criteria of Kawasaki disease, but were considered atypical Kawasaki based on the specific clinical signs and exclusion of other causes by serologic study and culture result. The patients' age ranged from 5 months to 11 years, with a mean of 22.2 months and a median of 15 months. The male to female ratio was 1.9:1. Twenty-five percent (5/20) of them had coronary arterial lesion. No difference was found in the age distribution, sex, and rate of coronary artery involvement between typical and atypical Kawasaki disease. All patients were treated with intravenous immunoglobulin and aspirin except for 2 patients. At follow-up, patients with coronary arterial lesions had a prognosis as good as those with typical Kawasaki disease. According to these observations, atypical Kawasaki disease may be part of Kawasaki disease occurring via the same pathogenesis, but has incomplete manifestation. Clinical practitioners should have a high index of suspicion to diagnose and initiate prompt treatment to reduce the comorbidity of coronary arterial disease in patients with atypical Kawasaki disease.

Results of the Lynn Sage Second-Opinion Program for local therapy in patients with breast carcinoma. Changes in management and determinants of where care is delivered

BACKGROUND

The treatment options of breast conservation therapy (BCT) and immediate reconstruction for patients with carcinoma of the breast have not been adopted widely. The objectives of this study were to determine how often a second opinion on the local therapy of breast carcinoma changed patient management and to identify factors predictive of remaining at the second-opinion site for therapy.

METHODS

Two hundred thirty-one patients with intraductal carcinoma or Stage I and II breast carcinoma were reviewed retrospectively. At the time of the second opinion, patients completed a questionnaire regarding their initial surgical opinion and the reason for seeking consultation.

RESULTS

Only 46% of patients had a complete discussion of treatment options prior to the second opinion. The second opinion changed management in 54 patients (20.3%). The most common finding was eligibility for BCT in patients who were offered only mastectomy. Definitive local therapy occurred at the second-opinion site in 65.8% of patients. The only predictors of remaining at the second-opinion site were insurance type (P = 0.008) and the patient's perception that options were not discussed at the initial opinion (P < 0.001).

CONCLUSIONS

Second opinions provide useful information to patients and may change the management of their disease. They result in significant patient capture for an institution.

Empirical monotherapy with meropenem in serious bacterial infections in children

The efficacy and safety profile of meropenem were analyzed according to data collected from hospitalized pediatric patients aged 4 days to 20 years who had serious bacterial infections and were treated in a major teaching hospital in Taipei. Of the 53 patients enrolled, 47 were analyzed for clinical efficacy and 53 for safety. The satisfactory clinical response rate was 57% in lower respiratory tract infection, 58% in septicemia, 100% in complicated urinary tract infection, osteomyelitis, and central nervous system infection, 83% in skin and soft tissue infection, and 93% in intra-abdominal infection. Eleven (21%) patients experienced adverse events related to meropenem. The most commonly observed adverse reactions were elevated hepatic enzymes (7.5%), increased alkaline phosphatase (3.8%), and thrombocytosis (3.8%). There was no meropenem-related seizure, withdrawal, or death. The results of this study suggested that meropenem is well tolerated even in young infants, and is effective in treating serious childhood bacterial infection. However, this study also identified a proportion of hospitalized pediatric patients with isolates that were resistant to meropenem. The trends in meropenem resistance among nosocomially acquired bacteria should be monitored closely.

A phase II study of irinotecan with 5-fluorouracil and leucovorin in patients with previously untreated gastric adenocarcinoma

BACKGROUND

A phase II study testing the safety and efficacy of irinotecan (CPT-11). 5-fluorouracil (5-FU), and leucovorin (LCV) was conducted in patients with advanced gastric adenocarcinomas.

PATIENTS AND METHODS

Patients with metastatic or recurrent adenocarcinoma of the gastroesophageal junction (GEJ) or stomach were entered onto this study. Previous chemotherapy for metastatic disease was not allowed. Treatment consisted of repeated 6-week cycles comprising CPT-11 125 mg/m2 intravenously (i.v.) followed immediately by LCV 20 mg/m2 i.v. and 5-FU 500 mg/m2 i.v., all given weekly for four weeks followed by a two-week rest.

RESULTS

Thirty-eight patients were enrolled and 36 eligible patients received protocol therapy. Grade 3-5 toxicities consisted primarily of neutropenia (36%) and diarrhea (28%). Neutropenic infection was observed in 14% of patients, with 3 (8%) dying of neutropenic sepsis. The overall response rate was 22% (95% confidence interval [CI] 8.5% to 35.5%). Median survival was 7.6 months, and median time to progression was 4.4 months.

CONCLUSION

This weekly regimen of CPT-11 with bolus 5-FU/LCV is active in patients with advanced adenocarcinomas of the stomach or gastroesophageal junction. While rates of grade 3-4 neutropenia and diarrhea were similar to those observed historically in patients receiving this regimen for colorectal cancer, neutropenic fever/sepsis appeared to be more frequent, and dose modifications were substantial. Future trials of this combination in patients with gastric cancer should decrease the absolute starting drug doses and/ or employ altered scheduling that better accommodates the pattern of toxicity.

Effects of calcium channel antagonists on the corpora allata of adult male loreyi leafworm Mythimna loreyi: juvenile hormone acids release and intracellular calcium level

The effects of voltage-dependent calcium channel (VDCC) antagonists and the non-specific calcium channel antagonists on both juvenile hormone acids (JHA) release and cytosolic free calcium concentration ([Ca2+]i) are investigated in the corpora allata (CA) of the adult males loreyi leafworm Mythimna loreyi. The VDCC antagonists used in this study are: the L-type antagonists diltiazem, nifedipine, and verapamil, the N-type antagonist omega-Conotoxin (CgTx) GVIA, the N- and P/Q-type antagonist omega-CgTx MVIIC, and the T-type antagonist amiloride. The non-specific calcium channel antagonists used in this study were cadmium (Cd2+), cobalt (Co2+), nickle (Ni2+), and lanthanum (La3+). The results show that both the DHPs-sensitive L-type antagonist nifedipine and the N-type antagonist omega-CgTx GVIA were able to inhibit JHA release, but only omega-CgTx GVIA was able to reduce the [Ca2+]i. Among the non-specific calcium channel antagonists, Cd2+ is the most potent in reducing JHA release but without obvious effect on the [Ca2+]i, La3+ significantly increases the [Ca2+]i but without effect on JHA release.

Baicalein induces a dual growth arrest by modulating multiple cell cycle regulatory molecules

Baicalein, a flavonoid present in the root of Scutellaria baicalensis Georgi, has been reported to inhibit cell proliferation in several types of cells. In this study, the effect of baicalein on cell growth and the mechanism of growth modulation were examined in primary cultured rat heart endothelial cells. Here, we report that treatment with 100-microM baicalein caused an almost complete inhibition of cell proliferation after 5 days of incubation. Baicalein mediated G1 and G2 growth arrest accompanied by the down-regulation of cyclin D2, cyclin A, cyclin-dependent kinase 1 (Cdk1) and cyclin-dependent kinase 2 (Cdk2), and up-regulation of p15(Ink4B), p21(CIP1/Waf1), p53 and cyclin E. Evaluation of the kinase activity of cyclin-Cdk complexes showed that baicalein decreased Cdk1, Cdk2, cyclin D2 and cyclin A expression in endothelial cells, leading to markedly reduced Cdk/cyclin-associated kinase activities. These results suggest that baicalein inhibits the proliferation of rat heart endothelial cells via G1 and G2 arrest in association with the down-regulation of the expression and function of Cdk1, Cdk2, cyclin D2 and cyclin A proteins, and up-regulation of cyclin E, p15(Ink4B), p53 and p21(CIP1/Waf1).

Protamine sulfate enhances the transduction efficiency of recombinant adeno-associated virus-mediated gene delivery

PURPOSE

The purpose of this study was to evaluate glucose responsiveness in HepG2 human hepatoma cells transduced by a recombinant adeno-associated virus (rAAV) vector containing the insulin gene promoter. and to investigate the effect of protamine sulfate on rAAV-mediated gene delivery.

METHODS

Recombinant AAV vector, AAV.Ins.Luc.delta EGFP, was employed to transduce HepG2 hepatoma cells. Virus infection was carried out either in the absence or presence of protamine sulfate, followed by fluorescence microscopic examination, luciferase activity assay, and flow cytometric analysis. Electrokinetic measurements were carried out to determine the effect of protamine sulfate on zeta potential of the cells and the virus.

RESULTS

Glucose-responsive luciferase gene expression was obtained in rAAV-transduced HepG2 cells. Addition of 5 microg/ml protamine reversed the zeta potential of the cells and the virus particles, leading to enhanced transgene expression in rAAV-transduced HepG2 cells. Enhancement of protamine sulfate on rAAV-mediated gene transfer was dose-dependent. Addition of more than 5 microg/ml protamine resulted in a reduction of infectability of the virus.

CONCLUSIONS

Glucose responsiveness in the millimolar concentration range can be obtained in rAAV-transduced HepG2 cells. Protamine sulfate, up to 5 microg/ml, enhanced the rAAV transduction efficiency in HepG2 cells. The enhancement was correlated with zeta potential of the cells and the virus.

Statistical measures of DNA sequence dissimilarity under Markov chain models of base composition

In molecular biology, the issue of quantifying the similarity between two biological sequences is very important. Past research has shown that word-based search tools are computationally efficient and can find some new functional similarities or dissimilarities invisible to other algorithms like FASTA. Recently, under the independent model of base composition, Wu, Burke, and Davison (1997, Biometrics 53, 1431 1439) characterized a family of word-based dissimilarity measures that defined distance between two sequences by simultaneously comparing the frequencies of all subsequences of n adjacent letters (i.e., n-words) in the two sequences. Specifically, they introduced the use of Mahalanobis distance and standardized Euclidean distance into the study of DNA sequence dissimilarity. They showed that both distances had better sensitivity and selectivity than the commonly used Euclidean distance. The purpose of this article is to extend Mahalanobis and standardized Euclidean distances to Markov chain models of base composition. In addition, a new dissimilarity measure based on Kullback-Leibler discrepancy between frequencies of all n-words in the two sequences is introduced. Applications to real data demonstrate that Kullback-Leibler discrepancy gives a better performance than Euclidean distance. Moreover, under a Markov chain model of order kQ for base composition, where kQ is the estimated order based on the query sequence, standardized Euclidean distance performs very well. Under such a model, it performs as well as Mahalanobis distance and better than Kullback-Leibler discrepancy and Euclidean distance. Since standardized Euclidean distance is drastically faster to compute than Mahalanobis distance, in a usual workstation/PC computing environment, the use of standardized Euclidean distance under the Markov chain model of order kQ of base composition is generally recommended. However, if the user is very concerned with computational efficiency, then the use of Kullback-Leibler discrepancy, which can be computed as fast as Euclidean distance, is recommended. This can significantly enhance the current technology in comparing large datasets of DNA sequences.

Regulated secretion of proinsulin/insulin from human hepatoma cells transduced by recombinant adeno-associated virus

To employ hepatocytes as surrogate beta-cells for gene therapy of diabetes, a regulatory system was devised in this study by placing the human insulin cDNA under the control of the phosphoenolpyruvate carboxykinase (PEPCK) promoter, followed by the cytomegalovirus immediate early promoter-driven enhanced-green-fluorescent-protein open reading frame. The expression cassette was inserted into the adeno-associated virus vector between two inverted terminal repeats, and used to produce recombinant adeno-associated virus (rAAV). HepG2 human hepatoma cells were transduced by rAAV at the desired multiplicity of infection, followed by treatment with various concentrations of retinoic acid, dexamethasone, dibutyryl cAMP (dbcAMP) and 3-isobutyl-1-methylxanthine (IBMX). The cell-culture media were collected at 8, 16 and 24 h later. Proinsulin/insulin levels were determined with human proinsulin/insulin radioimmunoassay kits. Transduction of HepG2 cells by rAAV showed that green fluorescence was produced as early as 12 h after rAAV infection. Flow-cytometrical analysis demonstrated that transduction efficiency increased with the numbers of transducing rAAV particles used. The transduced hepatocytes were shown to secrete immunoreactive proinsulin/insulin, which were stimulated by the concentrations of retinoic acid, dexamethasone and dbcAMP in the culture medium. High conversion from proinsulin into insulin occurred when these cells were treated with dexamethasone and dbcAMP. The presence of IBMX enhanced the secretion of proinsulin/insulin from the dbcAMP-treated cells. We conclude that rAAV is a promising vector for gene therapy of diabetes. Regulated secretion of proinsulin/insulin can be obtained in the rAAV-transduced HepG2 cells conferred with the PEPCK promoter via rAAV-mediated gene transfer.

Clinical outcome in children with recurrent craniopharyngioma after primary surgery

PURPOSE

The purpose of this article is to report the clinical outcome in children with recurrent craniopharyngioma after primary surgery. PATIENT AND MATERIALS: Fourteen children with craniopharyngioma treated with primary surgery developed local recurrence. The median time to recurrence from primary surgery was 19 months (range, 2-156 months). At first recurrence (n = 14), seven children (50%) underwent reoperation. Five children (36%) received radiotherapy, and two children did not undergo any treatment. At second recurrence (n = 7), six children underwent radiotherapy (86%), and one had surgery. External-beam radiation was delivered with 6-MV or 10-MV x-rays by use of three-dimensional conformal technique (n = 4) or fractionated stereotactic radiotherapy (n = 7) using the Laitinen stereoadapter. Total dose ranged from 54 to 55.8 Gy at 1.8 Gy/fraction.

RESULTS

The median follow-up from primary surgery is 8.5 years (range, 3-15.8 years). The 5-, 10-, and 15-year overall survival was 100%, 86%, and 86%, respectively, and the disease-free survival was 92%, 60%, and 60%, respectively. The median follow-up from date of first relapse was 6 years (range, 2.5-10 years). After treatment for first recurrence, the 2- and 5-year second-recurrence-free survival was 71% and 29%, respectively. After radiotherapy, the 2- and 5-year second-recurrence-free survival was 100% and 100%, respectively, compared with 43% and 0%, respectively, for surgery alone. Univariate analysis revealed significantly superior local control with radiotherapy compared with surgery. The local control rate at last follow-up, after stratifying for treatment at first and second recurrence, were analyzed at first and second relapse was 90% and 0% after radiotherapy and surgery, respectively. If radiotherapy was used for first or second recurrence, the 5-, 10-, and 15-year relapse-free survival was 100%, 83%, and 83%, respectively, compared with 67%, 0%, and 0%, respectively, for surgery alone. The median time to second relapse after surgery for first relapse was 12 months (range, 2-36 months). After primary surgery, all 14 children developed panhypopituitarism, requiring lifelong hormone supplementation. After surgery at recurrence, three children (3/7, 43%) experienced intraoperative bleeding, resulting in permanent neurologic deficits in two. No child has shown any signs of radiation-induced optic neuropathy.

DISCUSSION

In children with recurrent craniopharyngioma after radical resection, the use of three-dimensional conformal radiotherapy or fractioned stereotactic radiotherapy results in very good local control with a low incidence of complications. In young children with stable tiny recurrences, a policy of close surveillance could be adopted for the brain to mature before beginning radiotherapy. The use of secondary surgery for recurrent tumors is associated with a low cure rate and a high risk of complications.

Concomitant chemoradiotherapy as primary therapy for locoregionally advanced head and neck cancer

PURPOSE

To achieve locoregional control of head and neck cancer, survival, and organ preservation using intensive concomitant chemoradiotherapy.

PATIENTS AND METHODS

This study was a phase II trial of chemoradiotherapy with cisplatin 100 mg/m(2) every 28 days, infusional fluorouracil 800 mg/m(2)/d for 5 days, hydroxyurea 1 g orally every 12 hours for 11 doses, and radiotherapy twice daily at 1.5 Gy/fraction on days 1 through 5 (total dose, 15 Gy). Five days of treatment were followed by 9 days of rest, during which time patients received granulocyte colony-stimulating factor. Five cycles (three with cisplatin) were administered over 10 weeks (total radiotherapy dose, </= 75 Gy). Adjuvant chemoprevention with retinoic acid and interferon alfa-2A was offered.

RESULTS

Seventy-six patients were treated (stage IV, 93%; N2, 54%; N3, 21%). At a median follow-up of 38 months, the 3-year progression-free survival is 72%, locoregional control 92%, systemic control 83%, and overall survival 55%. Toxicities included mucositis (grade 3, 45%; grade 4, 12%), neutropenia (grade 4, 39%), and thrombocytopenia (grade 4, 53%). Surgery at the primary site was performed in 13 patients, and 39 had neck dissection. A majority of patients declined adjuvant chemoprevention. Pharmacokinetic parameters were not prognostic of tumor control. Quality of life declined during treatment but returned from good to excellent by 12 months after treatment.

CONCLUSION

Intensive concomitant chemoradiotherapy leads to high locoregional control and survival rates with organ preservation and a reversal of the historical pattern of failure (distant > locoregional). Surgery after concomitant chemoradiotherapy is feasible. Compliance with adjuvant chemoprevention is poor. Identification of less toxic regimens and improved distant disease control emerge as important future research goals.

Racial differences in prostate cancer related to loss of heterozygosity on chromosome 8p12-23

PURPOSE

To determine if there is a racial difference in prostate cancer related to loss of heterozygosity (LOH) on chromosome 8p12-23, the region most frequently altered in prostate cancer.

METHODS AND MATERIALS

A total of 51 prostate cancer patients, consisting of 23 African Americans and 28 Caucasians, were included in this study. All patients underwent radical prostatectomy, and patients in the two racial subgroups were matched for median serum PSA, Gleason score, and pathological stage of cancer. Paired normal prostate and cancer tissue DNA was isolated and amplified with 13 polymorphic markers mapped to 8p12-23 by radiolabeled polymerase chain reaction. The amplified products were resolved by polyacrylamide gel electrophoresis, autoradiographed, and analyzed for allelic losses.

RESULTS

The overall incidence of LOH at 8p12-23 was 53%, and 16% showed homozygous deletions. The incidence of LOH in Caucasians was 68% compared to 35% in African Americans. On univariate (p = 0.02) and multivariate logistic regression analysis (p = 0.02), only Caucasian race was a significant predictor for LOH. The other clinicopathologic parameters did not have any significant effect on incidence of LOH.

CONCLUSION

These results highlight the independent influence of Caucasian race on incidence of LOH at 8p12-23, and suggest that genetic differences at specific tumor suppressor loci may be a factor responsible for racial variations observed in prostate cancer.

Comparison of recovery characteristics of sevoflurane and halothane for outpatient surgery in infants

BACKGROUND

Sevoflurane, a newly approved potent inhaled anesthetic in Taiwan, provides rapid emergence from anesthesia in adults and children. Clinically, it is difficult to accurately assess the rate of recovery from anesthesia in infants. This study was designed to compare the emergence characteristics of halothane with those of sevoflurane having recourse to a respiratory agent monitor in infants undergoing outpatient surgery.

METHODS

Forty infants of ASA class I, scheduled for day-case urologic surgery were studied. Patients were randomly allocated to two groups of 20. Sevoflurane or halothane was used as the inhaled anesthetic. Toward the end of surgery, sevoflurane or halothane was turned off. The concentrations of exhaled sevoflurane or halothane were read every minute after its discontinuation until extubation. The decay curve of the exhaled concentration of either agent was recorded minute by minute for 10 minutes. The time intervals from discontinuation of the inhalation agent to spontaneous movement and tracheal extubation were recorded. Untoward side-effects during emergence were also compared.

RESULTS

Sevoflurane was eliminated faster than halothane. Based on the decay curves of the exhaled concentrations of the two agents, the time constant for halothane was 2.59 minutes and that for sevoflurane was only 1.43 minutes. The time from discontinuation of agent to extubation was also shorter for sevoflurane. Postoperative restlessness or agitation occurred more frequently in infants who received sevoflurane, although the difference was of no statistical significance.

CONCLUSIONS

Sevoflurane is superior to halothane for rapid elimination in infant outpatient surgery as gauged by observation of end-tidal concentration elimination curves recorded with a respiratory agent monitor. No other postoperative side-effect was evident in sevoflurane anesthesia.

Oral-facial-digital syndrome with Y-shaped fourth metacarpals and endocardial cushion defect

We report on a boy with pseudo-cleft of the upper lip, cleft palate, bifid uvula, lobulated tongue, hypoplasia of the epiglottis, both preaxial and central polydactyly of the hands (Y-shaped fourth metacarpals), bilateral preaxial polydactyly of the feet, postaxial polydactyly of the left foot, hearing impairment, and congenital heart disease with endocardial cushion defect. These clinical manifestations resembled oral-facial-digital syndrome type II (OFDS II, Mohr syndrome) or type VI (Váradi syndrome), associated with an atrioventricular canal. Clinical variability of OFDS II has been observed repeatedly. To the best of our knowledge, this is the first reported case of OFDS II with Y-shaped fourth metacarpals. In addition to Y-shaped fourth metacarpals, Mohr syndrome plus atrioventricular canal and hypoplasia of the epiglottis may represent an additional subgroup of OFDS.

Nonfunctioning pancreatic tumor manifestated as abdominal mass in a child

This report concerns a 9-year-old girl with a nonfunctioning pancreatic tumor presented as an abdominal mass. An encapsulated tumor, measuring approximately 8 x 7 cm, was found during operation, and debulking surgery was done. Histopathologic studies proved that it was a pancreatic tumor, compatible with non-functioning islet cell tumors. She displayed neither clinical picture of jaundice, nor excessive hormonal manifestations such as diarrhea or flushing. No evidence would suggest its association with multiple endocrine neoplasia type I. To our knowledge, it has never been reported in children in Taiwan.