Da Vinci SP robotic approach to colorectal surgery: two specific indications and short-term results

BACKGROUND

Da Vinci® Single Port (dvSP) was recently developed. Its application in colorectal surgery is under investigation. The aim of this study was to explore the safety and feasibility of dvSP for intersphincteric (dvSP-ISR), right colectomy (dvSP-RC), and transverse colectomy (dvSP-TC). Surgical indication and short-term results were analyzed.

METHODS

All consecutive patients from a prospective database of patients who underwent dvSP-ISR, dvSP-RC, and dvSP-TC at Korea University Anam Hospital from November 2020 to December 2021, were analyzed. Perioperative, pathological, and oncological short-term outcomes were analyzed.

RESULTS

A total of 7 dvSP-ISR, 5 dvSP-RC, and 1 dvSP-TC were performed. Median age was 56.0 (55.0-61.0) years for the dvSP-ISR and 54.0 (44.7-63.5) years for the dvSP-RC/TC. Median body mass index was 22.8 (17.1-24.8) kg/m² for the dvSP-ISR and 23.6 (20.8-26.9) kg/m² for the dvSP-RC/TC. All dvSP-ISR patients received neoadjuvant long-course chemoradiotherapy, including one patient with squamocellular carcinoma who was treated with 5-fluorouracil (5-FU)/mitomycin. All other patients, excluding one dvSP-RC patient with Crohn's disease, had an adenocarcinoma. Median operation time was 280 (240-370) minutes for the dvSP-ISR and 220 (201-270) minutes for the dvSP-RC/TC. Estimated blood loss was insignificant. No intraoperative complications or conversions to multiport/open surgery was reported. Median post-operative stay was 7.0 (6.0-10.0) days for the dvSP-ISR and 5.0 (4.0-6.7) days for the dvSP-RC/TC. Quality of mesorectum was complete for six patients, and nearly complete for one. Median number of retrieved lymph nodes were 21 (17-25) for the dvSP-ISR and 28 (24-49) for the dvSP-RC/TC. Proximal and distal resection margins were tumor free. Four patients experienced post-operative complications not related to the platform which were: ileus, voiding dysfunction, infected pelvic hematoma, and wound infection. Median follow-up was 9 (6-11) months and 11 (7-17) months for the dvSP-ISR and dvSP-RC/TC, respectively. Two patients had systemic recurrence; all others were tumor free.

CONCLUSIONS

The dvSP platform is safe and feasible for intersphincteric resection with right lower quadrant access, and right/transverse colectomy with suprapubic access. Further studies are needed to evaluate benefit differences compared to multiport robotic platform.

Assessments of the In Vitro and In Vivo Linker Stability and Catabolic Fate for the Ortho Hydroxy-Protected Aryl Sulfate Linker by Immuno-Affinity Capture Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometric Assay

Antibody-drug conjugate (ADC) linkers play an important role in determining the safety and efficacy of ADC. The Ortho Hydroxy-Protected Aryl Sulfate (OHPAS) linker is a newly developed linker in the form of a di-aryl sulfate structure consisting of phenolic payload and self-immolative group (SIG). In this study, using two bioanalytical approaches (namely "bottom-up" and "middle-up" approaches) via the liquid chromatography-quadrupole time-of-flight mass spectrometric (LC-qTOF-MS) method, in vitro and in vivo linker stability experiments were conducted for the OHPAS linker. For comparison, the valine-citrulline-p-aminobenzyloxycarbonyl (VC-PABC) linker was also evaluated under the same experimental conditions. In addition, the catabolite identification experiments at the subunit intact protein level were simultaneously performed to evaluate the catabolic fate of ADCs. As a result, the OHPAS linker was stable in the in vitro mouse/human plasma as well as in vivo pharmacokinetic studies in mice, whereas the VC-PABC linker was relatively unstable in mice in vitro and in vivo. This is because the VC-PABC linker was sensitive to a hydrolytic enzyme called carboxylesterase 1c (Ces1c) in mouse plasma. In conclusion, the OHPAS linker appears to be a good linker for ADC, and further experiments would be warranted to demonstrate the efficacy and toxicity related to the OHPAS linker.

Qualification and application of liquid chromatography-quadrupole time-of-flight mass spectrometric method for the determination of carisbamate in rat plasma and prediction of its human pharmacokinetics using physiologically based pharmacokinetic modeling

Carisbamate is an antiepileptic drug and it also has broad neuroprotective activity and anticonvulsant reaction. In this study, a liquid chromatography-quadrupole time-of-flight mass spectrometric (LC-qTOF-MS) method was developed and applied for the determination of carisbamate in rat plasma to support in vitro and in vivo studies. A quadratic regression (weighted 1/concentration²), with an equation y = ax² + bx + c, was used to fit calibration curves over the concentration range from 9.05 to 6,600 ng/mL for carisbamate in rat plasma. Preclinical in vitro and in vivo studies of carisbamate have been studied through the developed bioanalytical method. Based on these study results, human pharmacokinetic (PK) profile has been predicted using physiologically based pharmacokinetic (PBPK) modeling. The PBPK model was optimized and validated by using the in vitro and in vivo data. The human PK of carisbamate after oral dosing of 750 mg was simulated by using this validated PBPK model. The human PK parameters and profiles predicted from the validated PBPK model were similar to the clinical data. This PBPK model developed from the preclinical data for carisbamate would be useful for predicting the PK of carisbamate in various clinical settings.

Liquid chromatography-high resolution mass spectrometric method for the quantification of monomethyl auristatin E (MMAE) and its preclinical pharmacokinetics

MMAE is a potent antimitotic drug used as payload of an antibody-drug conjugate which shows potent activity in preclinical and clinical studies against a range of lymphomas, leukemia and solid tumors. Liquid chromatography-high resolution mass spectrometric method was developed for the quantification of MMAE and its preclinical pharmacokinetics. The method consisted of protein precipitation using acetonitrile (ACN) for sample preparation and liquid chromatography - quadrupole - time-of-flight - tandem mass spectrometry (LC-qTOF-MS/MS) analysis in the positive ion mode. A quadratic regression (weighted 1/concentration² ), with an equation y = ax²  + bx + c, was used to fit calibration curves over the concentration range of 1.01-2,200 ng/mL for MMAE. The qualification run met the acceptance criteria of ±25% accuracy and precision values for QC samples. Recovery was 42.84%. The dilution integrity was determined for 5-fold dilution and the accuracy and precision ranged within ±25%. The stability results indicated that MMAE was stable for the following conditions: short-term (4 h), long-term (4 weeks), freeze/thaw (3 cycles) and post-preparative stability (12 h). This qualified method was successfully applied to a pharmacokinetic study of MMAE in rat as a preclinical animal model. The PK results suggest that MMAE has moderate CL and low BA.Also, these results would be helpful in having a comprehensive understanding of the PK characteristics of MMAE and developing ADC in future.

Assessment of Pharmacokinetics and Metabolism Profiles of SCH 58261 in Rats Using Liquid Chromatography-Mass Spectrometric Method

5-Amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo(4,3-e)-1,2,4-triazolo(1,5-c) pyrimidine (SCH 58261) is one of the new chemical entities that has been developed as an adenosine A_2A receptor antagonist. Although SCH 58261 has been reported to be beneficial, there is little information about SCH 58261 from a drug metabolism or pharmacokinetics perspective. This study describes the metabolism and pharmacokinetic properties of SCH 58261 in order to understand its behaviors in vivo. Rats were used as the in vivo model species. First, an LC-MS/MS method was developed for the determination of SCH 58261 in rat plasma. A GastroPlus™ simulation, in vitro microsomal metabolic stability, and bile duct-cannulated studies were also performed to understand its pharmacokinetic profile. The parameter sensitivity analysis of GastroPlus™ was used to examine the factors that influence exposure when the drug is orally administered. The factors are as follows: permeability, systemic clearance, renal clearance, and liver first-pass effect. In vitro microsomal metabolic stability indicates how much the drug is metabolized. The extrapolated hepatic clearance value of SCH 58261 was 39.97 mL/min/kg, indicating that the drug is greatly affected by hepatic metabolism. In vitro microsomal metabolite identification studies revealed that metabolites produce oxidized and ketone-formed metabolites via metabolic enzymes in the liver. The bile duct-cannulated rat study, after oral administration of SCH 58261, showed that a significant amount of the drug was excreted in feces. These results imply that the drug is not absorbed well in the body after oral administration. Taken together, SCH 58261 showed quite a low bioavailability when administered orally and this was likely due to significantly limited absorption, as well as high metabolism in vivo.

In Vitro, In Silico, and In Vivo Assessments of Pharmacokinetic Properties of ZM241385

Parkinson’s disease is one of the most common neurodegenerative diseases. Adenosine regulates the response to other neurotransmitters in the brain regions related to motor function. In the several subtypes of adenosine receptors, especially, adenosine 2A receptors (A_2ARs) are involved in neurodegenerative conditions. ZM241385 is one of the selective non-xanthine A2AR antagonists with high affinity in the nanomolar range. This study describes the in vitro and in vivo pharmacokinetic properties of ZM241385 in rats. A liquid chromatography-quadrupole time-of-flight mass spectrometric (LC-qToF MS) method was developed for the determination of ZM241385 in rat plasma. In vivo IV administration studies showed that ZM241385 was rapidly eliminated in rats. However, the result of in vitro metabolic stability studies showed that ZM241385 had moderate clearance, suggesting that there is an extra clearance pathway in addition to hepatic clearance. In addition, in vivo PO administration studies demonstrated that ZM241385 had low exposure in rats. The results of semi-mass balance studies and the in silico PBPK modeling studies suggested that the low bioavailability of ZM241385 after oral administration in rats was due to the metabolism and by liver, kidney, and gut.

Management of isolated recurrence after surgery for pancreatic adenocarcinoma

BACKGROUND

Recurrence of pancreatic cancer after primary pancreatectomy occurs in the vast majority of patients. The role of surgical treatment for recurrent pancreatic cancer is not well established.

METHODS

Patients who underwent primary pancreatectomy with curative intent from 2000 to 2014 at a single large-volume centre were evaluated retrospectively. CT or PET was used to select patients with an isolated recurrence. The clinicopathological features and survival outcomes were compared according to treatment modalities.

RESULTS

Of the 1610 patients with pancreatic cancer who underwent resection, 1346 (83·6 per cent) were diagnosed with recurrent pancreatic cancer. Recurrence was locoregional in 366 patients (27·2 per cent), distant multifocal in 251 (18·6 per cent), distant isolated in 188 (14·0 per cent), locoregional plus distant in 153 (11·4 per cent) and peritoneal seeding in 388 (28·8 per cent). Of the 1346 patients with recurrence, 197 (14·6 per cent) had isolated recurrence; of these, 48 (24·4 per cent of all isolated recurrences; 3·6 per cent of all recurrences) underwent resection. Median survival of the 197 patients after diagnosis of isolated recurrence was 14·7 months; it was longer in patients who underwent surgical resection than among those treated non-surgically (23·5 versus 12·0 months; P = 0·014). Multivariable analysis showed that chemotherapy and resection for recurrence were associated with better prognosis. Median survival after recurrence was longest in the 23 patients with isolated pulmonary recurrence (33·3 months). Survival after recurrence was better in patients who underwent resection of isolated recurrence in the remnant pancreas (median 28·0 versus 12·0 months, P = 0·010) and lung (median 36·5 versus 9·5 months; P = 0·010) than in those who did not undergo resection.

CONCLUSION

Surgical resection may be considered an option for treatment of patients with isolated recurrent pancreatic cancer.

Quantitative Analysis of Tozadenant Using Liquid Chromatography-Mass Spectrometric Method in Rat Plasma and Its Human Pharmacokinetics Prediction Using Physiologically Based Pharmacokinetic Modeling

Tozadenant is one of the selective adenosine A2a receptor antagonists with a potential to be a new Parkinson's disease (PD) therapeutic drug. In this study, a liquid chromatography-mass spectrometry based bioanalytical method was qualified and applied for the quantitative analysis of tozadenant in rat plasma. A good calibration curve was observed in the range from 1.01 to 2200 ng/mL for tozadenant using a quadratic regression. In vitro and preclinical in vivo pharmacokinetic (PK) properties of tozadenant were studied through the developed bioanalytical methods, and human PK profiles were predicted using physiologically based pharmacokinetic (PBPK) modeling based on these values. The PBPK model was initially optimized using in vitro and in vivo PK data obtained by intravenous administration at a dose of 1 mg/kg in rats. Other in vivo PK data in rats were used to validate the PBPK model. The human PK of tozadenant after oral administration at a dose of 240 mg was simulated by using an optimized and validated PBPK model. The predicted human PK parameters and profiles were similar to the observed clinical data. As a result, optimized PBPK model could reasonably predict the PK in human.

Rapid and simultaneous quantification of a mixture of biopharmaceuticals by a liquid chromatography/quadrupole time-of-flight mass spectrometric method in rat plasma following cassette-dosing

RATIONALE

The cassette-dosing technique is a technique that administers various drugs to a single animal at once and quantitated simultaneously. The purpose of this study was to evaluate the feasibility of cassette-dosing as a means of increasing throughput and decreasing animal usage for pharmacokinetic studies of biopharmaceuticals using liquid chromatography/time-of-flight mass spectrometric (LC/TOF-MS) analysis.

METHODS

Brentuximab, trastuzumab, cetuximab and adalimumab were used as model biopharmaceuticals. The method consisted of immunoprecipitation followed by tryptic digestion for sample preparation and LC/TOF-MS analysis of specific signature peptides in the positive ion mode using electrospray ionization. The specific signature peptides used for quantification were from the complementarity-determining regions of each mAb. All rats received a single intravenous bolus injection containing either a single mAb or a mixture of four mAbs.

RESULTS

The proposed method has been qualified in linearity range of 1-100 μg/mL with correlation coefficients higher than 0.990. The qualification run met the acceptance criteria of ±25% accuracy and precision values for quality control (QC) samples. This qualified LC/TOF-MS method was successfully applied to a pharmacokinetic study in the rat. The PK properties of mAbs administered as a cassette-dosage were similar to the pharmacokinetics of each antibody drug when administered as a single entity.

CONCLUSIONS

These findings suggest that the cassette-dosing approach could be used to evaluate the PK properties of biopharmaceuticals in the early drug discovery stage. Also, this method would be useful for other preclinical sample analysis without developing new reagents for sample preparation.

Qualification and Application of a Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometric Method for the Determination of Adalimumab in Rat Plasma

A liquid chromatography–quadrupole time-of-flight (Q-TOF) mass spectrometric method was developed for early-stage research on adalimumab in rats. The method consisted of immunoprecipitation followed by tryptic digestion for sample preparation and LC-QTOF-MS/MS analysis of specific signature peptides of adalimumab in the positive ion mode using electrospray ionization. This specific signature peptide is derived from the complementarity-determining region (CDR) of adalimumab. A quadratic regression (weighted 1/concentration), with an equation y = ax² + bx + c, was used to fit calibration curves over the concentration range of 1–100 μg/mL for adalimumab. The qualification run met the acceptance criteria of ±25% accuracy and precision values for quality control (QC) samples. This qualified LC-QTOF-MS/MS method was successfully applied to a pharmacokinetic study of adalimumab in rats as a case study. This LC-QTOF-MS/MS approach would be useful as a complementary method for adalimumab or its biosimilars at an early stage of research.

Orthopedic injuries associated with jet-skis (personal watercrafts): A review of 127 inpatients

BACKGROUND

Personal watercrafts (PWC) account for a disproportionate amount of water based injuries. Current literature suggests those with less PWC experience are more at risk for injury. Previous studies have not specifically evaluated the orthopedic implications of PWC usage or how various mechanisms of injury (MOI) contribute to different injury patterns.

HYPOTHESIS

PWC injuries will frequently require orthopedic intervention. The presence of an orthopedic injury will result in increased injury severity score (ISS), hospital and intensive care unit (ICU) length of stay (LOS). Patients visiting our region will have less PWC experience and so are more prone to serious injuries.

MATERIALS AND METHODS

Retrospective cohort study at a single Level 1 trauma center of admitted patients sustaining PWC injuries from 02/2004-03/2017. The following were studied: demographics, mechanism, season, ISS, hospital and ICU LOS, follow-up, fracture characteristics and management.

RESULTS

Hundred and twenty-seven patients were admitted due to PWC injury, 66 (52.0%) sustained an orthopedic injury, totaling 103 fractures (48 [46.6%] lower extremity, 26 [25.2%] upper extremity, 14 [13.6%] vertebral, 11 [10.7%] pelvic ring and 4 [3.9%] acetabulum). The mean age of orthopedic patients was 29 years (range 8-62). Handle bar injuries were significantly associated with open fractures, (13 of 25 open fractures, 3 of which became infected). Injuries occurring during the winter were associated with a higher ISS, yet more injuries occurred in the summer. A patient being a "visitor" to the region did not influence ISS. The mean LOS was 12.6 days for orthopedic patients. Eighteen orthopedic patients (27.3%) required ICU admission and 36 (54.5%) patients required orthopedic surgery (mean 2.11 operations).

DISCUSSION

A majority of PWC injuries resulted in extremity fractures with a moderate percentage requiring orthopedic surgery. Correlations between PWC experience and injury incidence can provide information for increased safety.

LEVEL OF EVIDENCE

IV; retrospective.

A single liquid chromatography-quadrupole time-of-flight mass spectrometric method for the quantification of total antibody, antibody-conjugated drug and free payload of antibody-drug conjugates

A single hybrid affinity-captured-LC-TOF-MS/MS method was developed and applied for the quantification of total antibody, antibody conjugated drug and free payload of antibody drug conjugate (ADC). Adcetris®, a valine-citrulline monomethyl auristatin E conjugated ADC, was used as a model ADC compound. A quadratic regression (weighted 1/concentration) was used to fit calibration curves over the concentration range 30.65-613.00 ng/mL with an equation y = ax²  + bx + c for the antibody-conjugated drug of Adcetris®. The qualification run met the acceptance criteria of ±25% accuracy and precision values for quality control samples. For the analysis of total antibody, a signature peptide (TTPPVLDSDGSFFLYSK, molecular weight 1874) was used after affinity capture using magnetic beads and on-bead trypsin digestion. A quadratic regression (weighted 1/concentration) was used to fit calibration curves over the concentration range 5.00-100.00 μg/mL with an equation y = ax²  + bx + c for total antibody. For free payload analysis of monomethyl auristatin E, a protein precipitation method followed by LC-TOF-MS/MS analysis was used. A quadratic regression (weighted 1/concentration) was used to fit calibration curves over the concentration range 1.01-2200 ng/mL with an equation y = ax²  + bx + c for free payload. Pharmacokinetic study samples and in vitro stability samples in rat were successfully analyzed by this a hybrid affinity-captured-LC-TOF-MS/MS method. This single platform method is a useful complementary method for the pharmacokinetics study of ADC with valine-citrulline linker at the early drug discovery stage.

Effect of the sexual abstinence period recommended by the World Health Organization on clinical outcomes of fresh embryo transfer cycles with normal ovarian response after intracytoplasmic sperm injection

This study was to investigate whether the sexual abstinence period (SAP) recommended by the World Health Organization (WHO) affects clinical outcomes. We compared the rate of clinical outcomes between 2-7 and ≥8 days of SAP in first fresh embryo transfer after intracytoplasmic sperm injection (ICSI) in groups of young maternal age (YMA: <38 years) and old maternal age (OMA: ≥38 years). We conducted a retrospective study of 449 first ICSI cycles with a normal ovarian response. SAP was identified before collecting the semen samples. Semen analysis was performed based on the guidelines recommended by WHO (2010). Sperm preparation was made using the swim-up method. Patients' baseline characteristics in the YMA and OMA groups did not differ. The rates of fertilisation, top-quality embryos on day 3, biochemical pregnancy, clinical pregnancy, ongoing pregnancy, abortion and implantation per cycle were not significantly different between 2-7 and ≥8 days of SAP in the YMA or OMA group. In conclusion, SAP beyond the recommended period by WHO was not associated with the rates of a lower fertilisation and pregnancy in human in vitro fertilisation (IVF). We think that a new criterion of SAP for clinical application in human IVF needs to be considered by WHO.

Quantification and application of a liquid chromatography-tandem mass spectrometric method for the determination of WKYMVm peptide in rat using solid-phase extraction

A liquid chromatographic-electrospray ionization-time-of-flight/mass spectrometric (LC-ESI-TOF/MS) method was developed and applied for the determination of WKYMVm peptide in rat plasma to support preclinical pharmacokinetics studies. The method consisted of micro-elution solid-phase extraction (SPE) for sample preparation and LC-ESI-TOF/MS in the positive ion mode for analysis. Phenanthroline (10 mg/mL) was added to rat blood immediately for plasma preparation followed by addition of trace amount of 2 m hydrogen chloride to plasma before SPE for stability of WKYMVm peptide. Then sample preparation using micro-elution SPE was performed with verapamil as an internal standard. A quadratic regression (weighted 1/concentration² ), with the equation y = ax²  + bx + c was used to fit calibration curves over the concentration range of 3.02-2200 ng/mL for WKYMVm peptide. The quantification run met the acceptance criteria of ±25% accuracy and precision values. For quality control samples at 15, 165 and 1820 ng/mL from the quantification experiment, the within-run and the between-run accuracy ranged from 92.5 to 123.4% with precision values ≤15.1% for WKYMVm peptide from the nominal values. This novel LC-ESI-TOF/MS method was successfully applied to evaluate the pharmacokinetics of WKYMVm peptide in rat plasma.

Monitoring rate and predictability of intraoperative monitoring in patients with intradural extramedullary and epidural metastatic spinal tumors

STUDY DESIGN

Single-center retrospective study.

OBJECTIVES

To evaluate the monitoring rate, sensitivity and specificity of intraoperative monitoring (IOM) during removal of intradural extramedullary (IDEM) or epidural metastatic spinal tumors. Also, to assess the efficacy of monitoring somatosensory-evoked potentials (SSEP) when motor-evoked potentials (MEP) are not measurable.

SETTING

The Neuro-Oncology Clinic, National Cancer Center, Korea.

METHODS

Patients (n=101) with IDEM or epidural metastatic spinal tumors at the cord level underwent surgeries monitored with SSEP and/or MEP. The monitoring rate was defined as negative when MEP or SSEP could not be measured after reversal of the neuromuscular block under general anesthesia. Positive IOM changes included more than a 50% change in the MEP or SSEP amplitude and more than a 10% delay in SSEP latency.

RESULTS

MEP was measurable in 73% of patients. The MEP monitoring rate in patients with motor power grades of 3 or less was 39%, which was lower than that of SSEP (83%). The sensitivity, specificity and predictability of MEP for motor changes were 93, 90 and 91%, respectively. Conversely, the sensitivity, specificity and predictability of SSEP were 62, 97 and 89%, respectively. In patients in whom MEP was not measurable (n=24), SSEP was monitored with a predictability of 83%.

CONCLUSION

In cases of extramedullary spinal tumors, MEP shows a higher sensitivity than SSEP does. However, the monitoring rate of MEP in non-ambulatory patients was lower than that of SSEP. In those cases, SSEP can be useful to monitor for postoperative neurological deficits.

Drug-drug interaction of microdose and regular-dose omeprazole with a CYP2C19 inhibitor and inducer

PURPOSE

A microdose drug-drug interaction (DDI) study may be a valuable tool for anticipating drug interaction at therapeutic doses. This study aimed to compare the magnitude of DDIs at microdoses and regular doses to explore the applicability of a microdose DDI study.

PATIENTS AND METHODS

Six healthy male volunteer subjects were enrolled into each DDI study of omeprazole (victim) and known perpetrators: fluconazole (inhibitor) and rifampin (inducer). For both studies, the microdose (100 μg, cold compound) and the regular dose (20 mg) of omeprazole were given at days 0 and 1, respectively. On days 2-9, the inhibitor or inducer was given daily, and the microdose and regular dose of omeprazole were repeated at days 8 and 9, respectively. Full omeprazole pharmacokinetic samplings were performed at days 0, 1, 8, and 9 of both studies for noncompartmental analysis.

RESULTS

The magnitude of the DDI, the geometric mean ratios (with perpetrator/omeprazole only) of maximum concentration (C_max) and area under the curve to the last measurement (AUC_t) of the microdose and the regular dose were compared. The geometric mean ratios in the inhibition study were: 2.17 (micro) and 2.68 (regular) for C_max, and 4.07 (micro), 4.33 (regular) for AUC_t. For the induction study, they were 0.26 (micro) and 0.21 (regular) for C_max, and 0.16 (micro) and 0.15 (regular) for AUC_t. There were no significant statistical differences in the magnitudes of DDIs between microdose and regular-dose conditions, regardless of induction or inhibition.

CONCLUSION

Our results may be used as partial evidence that microdose DDI studies may replace regular-dose studies, or at least be used for DDI-screening purposes.

Prediction of pharmacokinetics and drug-drug interaction potential using physiologically based pharmacokinetic (PBPK) modeling approach: A case study of caffeine and ciprofloxacin

Over the last decade, physiologically based pharmacokinetics (PBPK) application has been extended significantly not only to predicting preclinical/human PK but also to evaluating the drug-drug interaction (DDI) liability at the drug discovery or development stage. Herein, we describe a case study to illustrate the use of PBPK approach in predicting human PK as well as DDI using in silico, in vivo and in vitro derived parameters. This case was composed of five steps such as: simulation, verification, understanding of parameter sensitivity, optimization of the parameter and final evaluation. Caffeine and ciprofloxacin were used as tool compounds to demonstrate the “fit for purpose” application of PBPK modeling and simulation for this study. Compared to caffeine, the PBPK modeling for ciprofloxacin was challenging due to several factors including solubility, permeability, clearance and tissue distribution etc. Therefore, intensive parameter sensitivity analysis (PSA) was conducted to optimize the PBPK model for ciprofloxacin. Overall, the increase in C_max of caffeine by ciprofloxacin was not significant. However, the increase in AUC was observed and was proportional to the administered dose of ciprofloxacin. The predicted DDI and PK results were comparable to observed clinical data published in the literatures. This approach would be helpful in identifying potential key factors that could lead to significant impact on PBPK modeling and simulation for challenging compounds.

Ecklonia cava promotes hair growth

BACKGROUND

Previous studies have reported the protective effects on skin elasticity of the edible marine seaweed Ecklonia cava, which acts through regulation of both antioxidative and anti-inflammatory responses.

AIM

We evaluated the effect of E. cava and one of its components, dioxinodehydroeckol, on hair-shaft growth in cultured human hair follicles and on hair growth in mice.

METHODS

The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was used to check cell viability of human dermal papilla cells (DPCs) and outer root sheath (ORS) cells after treatment with E. cava and its metabolite, dioxinodehydroeckol. Hair-shaft growth was measured using the in vitro hair-follicle organ-culture system, in the presence or absence of E. cava and dioxinodehydroeckol. Anagen induction activity was examined by topical application of E. cava to the dorsal skin of C57BL/6 mice. Insulin-like growth factor (IGF)-1 expression was measured by reverse transcriptase PCR and ELISA.

RESULTS

The proliferation activity was found to be highest for the ethyl acetate-soluble fraction of E. cava (EAFE) in DPCs and in ORS cells. Treatment with EAFE resulted in elongation of the hair shaft in cultured human hair follicles, and promoted transition of the hair cycle from the telogen to the anagen phase in the dorsal skin of C57BL/6 mice. In addition, EAFE induced an increase in IGF-1 expression in DPCs. Dioxinodehydroeckol, a component of E. cava, induced elongation of the hair shaft, an increase in proliferation of DPCs and ORS cells, and an increase in expression of IGF-1 in DPCs.

CONCLUSIONS

These results suggest that E. cava containing dioxinodehydroeckol promotes hair growth through stimulation of DPCs and ORS cells.

Combined surgical and endovascular management of a giant fusiform PCA aneurysm in a pediatric patient. A case report

Treatment of intracranial giant aneurysms presents is challenging. In the case of pediatric giant aneurysm, more challenges arise. We describe our experience with a 17-year-old pediatric patient who presented with severe headache. She was diagnosed as having a giant fusiform aneurysm at the right P1-P2-Pcom junction. The aneurysm was treated with superficial temporal artery-posterior cerebral artery bypass and subsequent coil embolization of the aneurysm with parent artery occlusion. The patient had an excellent outcome at one-year follow-up. Our case suggests a combined approach of surgical and endovascular management may yield a better outcome than surgery or endovascular management alone in the treatment of pediatric giant aneurysm.

Risk factors for post-operative venous thromboembolism in patients with a malignancy of the lower limb

It is important to be able to identify patients with an increased risk of venous thromboembolism (VTE) in order to minimise the risk of an event. We investigated the incidence and risk factors for post-operative VTE in 168 consecutive patients with a malignancy of the lower limb. The period of study included ten months before and 12 months after the introduction of chemical thromboprophylaxis. All data about the potential risk factors were identified and classified into three groups (patient-, surgery- and tumour-related). The outcome measure was a thromboembolic event within 90 days of surgery. Of the 168 patients, eight (4.8%) had a confirmed symptomatic deep-vein thrombosis and one (0.6%) a fatal pulmonary embolism. Of the 28 variables tested, age > 60 years, higher American Society of Anesthesiologists grade and metastatic tumour were independent risk factors for VTE. The overall rate of symptomatic VTE was not significantly different between patients who received chemical thromboprophylaxis and those who did not. Knowledge of these risk factors may be of value in improving the surgical outcome of patients with a malignancy of the lower limb.

A randomized, multi-center, open-label, phase II study of once-per-cycle DA-3031, a biosimilar pegylated G-CSF, compared with daily filgrastim in patients receiving TAC chemotherapy for early-stage breast cancer

BACKGROUNDS

A pegylated form of recombinant granulocyte-colony stimulating factor (G-CSF) was developed for prophylactic use in breast cancer. The aim of this study was to evaluate the efficacy and safety of once-per-cycle DA-3031 in patients receiving chemotherapy for breast cancer.

METHODS

A total of 61 patients receiving docetaxel, doxorubicin, and cyclophosphamide (TAC) chemotherapy were randomized in cycle 1 to receive daily injections of filgrastim (100 μg/m(2)) or a single subcutaneous injection of pegylated filgrastim DA-3031 at a dose of either 3.6 mg or 6 mg.

RESULTS

The mean duration of grade 4 neutropenia in cycle 1 was comparable among the treatment groups (2.48, 2.20, and 2.05 days for filgrastim, DA-3031 3.6 mg and 6 mg, respectively; P=0.275). No statistically significant differences were observed in the incidence of febrile neutropenia between the treatment groups (9.5 %, 15.0 %, and 5.0 % for filgrastim, DA-3031 3.6 mg and 6 mg, respectively; P=0.681) in cycle 1. The incidences of adverse events attributable to G-CSF were similar among the treatment groups.

CONCLUSIONS

Fixed doses of 3.6 mg or 6 mg DA-3031 have an efficacy comparable to that of daily injections of filgrastim in ameliorating grade 4 neutropenia in patients receiving TAC chemotherapy.

Cryoplasty offers no advantage over standard balloon angioplasty for the treatment of in-stent stenosis

In-stent restenosis is the primary failure mode of endovascular treatment of occlusive disease in the femeropopliteal segment. Cryoplasty has been proposed to reduce intimal hyperplasia through induction of apoptosis. We sought to evaluate the efficacy of cryoplasty for treatment of in-stent restenosis compared to conventional balloon angioplasty (CBA). After IRB approval, a retrospective record review was performed of reinterventions for in-stent restenosis by a single vascular surgery group at a university hospital. Reinterventions involving cryoplasty and CBA were evaluated at 1, 3, 6 and 12 months after intervention with duplex imaging to identify significant recurrent stenosis utilizing established velocity criteria. Data collected included basic demographic information and comorbidities as well as time to restenosis. Statistical analysis was performed using Kaplan–Meier survival curves with the log rank test, Wilcoxon rank test, and Cox proportional hazards models. From December 2004 to November 2007, 76 reinterventions were performed using CBA (n = 39) or cryoplasty (n = 37) for in-stent restenosis without placement of additional stents. Periprocedural technical success (>30% residual stenosis) was 100% for both groups, with no complications. The two cohorts were statistically similar in mean age, gender, comorbidities, tobacco use and use of statins, aspirin and Plavix. However, the mean lesion length was significantly longer in the cryoplasty cohort (CBA: 140.9 mm, Cyro: 191.7 mm; P = 0.032). The mean time to recurrent stenosis or need for additional secondary intervention was significantly shorter for the cyroplasty cohort than for the CBA, 4.09 and 10.79 months, respectively ( P = .0001). Recurrent stenosis-free survival was significantly lower in the cyroplasty cohort at 3 months (CBA: 96.9%, Cyro: 88.9%) and 6 months (CBA: 84.0%, Cyro: 43.8%; P = .0089). Cyroplasty as a modality for treatment of in-stent stenosis in the femoropopliteal segment offers no benefit over CBA.

Feasibility study on development of Cerenkov fiber-optic dosimeter for radiotherapy application

To obtain real-time dose information in photon-beam therapy using a clinical linear accelerator, we fabricated a novel Cerenkov fiber-optic dosimeter using two plastic optical fibers without employing a scintillator. In this study, the light intensity and spectrum of Cerenkov radiation induced by a high-energy photon beam were measured as functions of the irradiation angle and the length difference between the two plastic optical fibers in the dosimeter probe. Also, we obtained a percentage depth dose curve for a 6 MV photon beam with a field size of 10 × 10 cm(2) according to the depth of the solid water phantom. Based on the results of this study, it is anticipated that the proposed Cerenkov fiber-optic dosimeter can be developed as a useful dosimeter to accurately obtain dose information prior to conducting radiotherapy.

Removal of dimethyl sulfide utilizing activated carbon fiber-supported photocatalyst in continuous-flow system

The present study investigated the adsorptional photocatalytic decomposition (APD) efficiency of activated carbon fiber-supported TiO(2) (ACF/TiO(2)) in a continuous-flow reactor for the removal of dimethyl sulfide (DMS). The SEM analysis identified that the ACF/TiO(2) exhibited the same tridimensional shape as uncovered ACF and that a TiO(2) photocatalyst could be embedded in the surface of the ACF. In the absence of UV light, the time-series removal efficiencies by ACF and the ACF/TiO(2) units exhibited a similar pattern, which decreased gradually as it reached close to zero. However, the APD efficiency determined via the ACF/TiO(2) with UV light remained at nearly 60% during the remaining courses of the 13-h period, after decreasing from a maximum APD of 80%. The APD efficiencies depended upon the weights of the TiO(2) embedded into the ACFs, the UV sources, the relative humidity, and DMS input concentrations. During a long-term (219-h) APD test, the APD efficiencies dropped from 80% to ca 60% within 1h after the initiation of the APD process and then fluctuated between 52% and 60%. No byproducts were measurable or observable in the effluent gas or on the ACF/TiO(2) surface. Consequently, the continuous-flow ACF/TiO(2) system could effectively be applied to control DMS without any significant functional deterioration.

Abstract P2-09-01: Serial [18F] FDG-PET after the 2nd Cycle of Preoperative Chemotherapy Is Predictive for Pathological Complete Response in Stage II/III Breast Cancer

Purpose: One of substudies of the prospective trials aimed to evaluate the usefulness of serial [18F] 2-fluoro-2-deoxy-D-glucose-positron emission tomography ([18F] FDG-PET) for predicting pathological complete response (pCR) in stage II/III breast cancer with preoperative chemotherapy (PST).

Methods: Serial PET was undertaken in 57 breast cancer patients enrolled in three different neoadjuvant trials: 35 patients from a phase II study with paclitaxel/gemcitabine/trastuzumab with ClinicalTrial.gov NCT 00532857, 9 patients from a phase Ib study with paclitaxel/gemcitabine/lapatinib with ClinicalTrial.gov NCT 01133912, and 13 patients from a phase Ib with paclitaxel/gemcitabine/sunitinib with ClinicalTrial.gov NCT0 1070706. All patients received 6 cycles of PST followed by surgery and radiotherapy. We assessed the peak standardized uptake value (SUVp) in the primary tumor at the baseline and after the 2nd cycle (37 patients) or after completion (20 patients) of 6 cycles of PST, and calculated the reduction rate (RR) of the SUVp. Pathological response was classified into pCR and non-pCR. To compare the mean of SUVp and RR of SUVp between different response groups, two-way tables and chi-square tests were used

Results: Fifteen (40.6%) of 37 patients who took repeat PET after the 2nd PST and 15 (75%) of 20 patients after completion of PST achieved a pCR with overall pCR rate of 52.6% in the primary tumor. In patients with repeat PET after the 2nd PST, post-treatment SUVp and RR of the SUVp in primary tumors were significantly different by the pathological response (post-treatment SUVp, 1.54 ± 0.63 in pCR vs 2.54 ± 1.06 in non-pCR, P=0.002; RR of the SUVp, 79.2% ± 11.9% in pCR vs 68.9% ± 15.4% in non-pCR, P=0.03). However, in patients with repeat PET after completion of PST, there were no statistical differences of these values (post-treatment SUVp, 1.09 ± 0.63 in pCR vs 1.29 ± 0.36 in non-pCR, P=0.42; RR of the SUVp, 83.7% ± 14.0% in pCR vs 67.5% ± 21.1% in non-pCR, P=0.17)

Conclusions: This study demonstrated that repeat PET after the 2nd cycle of PST, not after completion of PST could predict pCR in stage II/III breast cancer with preoperative chemotherapy. Acknowledgement NCC Grant #0910320.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-09-01.

Effects of changes in the physical properties of the central elastic artery on haemodynamic characteristics during ageing

The change in blood pressure during the ageing process depends on the changes in the physical properties of the arterial system. The conventional method of studying ageing, i.e. observing a focus group of people, requires long periods of time and also makes it difficult to separate the ageing effect from the effects of complex geriatric diseases. Therefore, a computer simulation was used to analyse how physical property changes in the central elastic artery during the ageing process affect the blood pressure and input impedance of the blood vessels. An increase in the arterial stiffness and an increase in the wall thickness increased the systolic pressure and the pulse pressure. An increase in the lumen diameter decreased the mean pressure. The pulse wave velocity and shape were changed in the central elastic artery group but were not changed outside this group. Also, the input impedance at a low frequency was increased in the central elastic artery group but was not changed outside this group. In this study, the way in which changes in specific physical properties of the artery affect the haemodynamic characteristics during ageing was analysed.

l-Ascorbic acid 2-phosphate promotes elongation of hair shafts via the secretion of insulin-like growth factor-1 from dermal papilla cells through phosphatidylinositol 3-kinase

BACKGROUND

l-Ascorbic acid 2-phosphate (Asc 2-P), a derivative of l-ascorbic acid, promotes elongation of hair shafts in cultured human hair follicles and induces hair growth in mice.

OBJECTIVES

To investigate whether the promotion of hair growth by Asc 2-P is mediated by insulin-like growth factor-1 (IGF-1) and, if so, to investigate the mechanism of the Asc 2-P-induced IGF-1 expression.

METHODS

Dermal papilla (DP) cells were cultured and IGF-1 level was measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay after Asc 2-P treatment in the absence or presence of LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor. Also, hair shaft elongation in cultured human scalp hair follicles and proliferation of cocultured keratinocytes were examined after Asc 2-P treatment in the absence or presence of neutralizing antibody against IGF-1. In addition, keratinocyte proliferation in cultured hair follicles after Asc 2-P treatment in the absence or presence of LY294002 was examined by Ki-67 immunostaining.

RESULTS

IGF-1 mRNA in DP cells was upregulated and IGF-1 protein in the conditioned medium of DP cells was significantly increased after treatment with Asc 2-P. Immunohistochemical staining showed that IGF-1 staining is increased in the DP of cultured human hair follicles by Asc 2-P. The neutralizing antibody against IGF-1 significantly suppressed the Asc 2-P-mediated elongation of hair shafts in hair follicle organ culture and significantly attenuated Asc 2-P-induced growth of cocultured keratinocytes. LY294002 significantly attenuated Asc 2-P-inducible IGF-1 expression and proliferation of follicular keratinocytes in cultured hair follicles.

CONCLUSIONS

These data show that Asc 2-P-inducible IGF-1 from DP cells promotes proliferation of follicular keratinocytes and stimulates hair follicle growth in vitro via PI3K.

The effect of bupivacaine.HCl on the physical properties of neuronal membranes

Fluorescent probe techniques were used to evaluate the effect of bupivacaine.HCl on the physical properties (transbilayer asymmetric lateral and rotational mobilities, annular lipid fluidity and protein distribution) of synaptosomal plasma membrane vesicles (SPMVs) isolated from bovine cerebral cortex. An experimental procedure was used based on selective quenching of both 1,3-di(1-pyrenyl)propane (Py-3-Py) and 1,6-diphenyl-1,3,5-hexatriene (DPH) by trinitrophenyl groups, and radiationless energy transfer (RET) from the tryptophans of membrane proteins to Py-3-Py. Bupivacaine.HCl increased the bulk lateral and rotational mobilities, and annular lipid fluidity in SPMVs lipid bilayers, and had a greater fluidizing effect on the inner monolayer than that of the outer monolayer. The magnitude of increasing effect on annular lipid fluidity in SPMVs lipid bilayer induced by bupivacaine.HCl was significantly far greater than magnitude of increasing effect of the drug on the lateral and rotational mobilities of bulk SPMVs lipid bilayer. It also caused membrane proteins to cluster. These effects of bupivacaine.HCl on neuronal membranes may be responsible for some, though not all, of the local anesthetic actions of bupivacaine.HCl.

Coil Knotting during Endovascular Coil Embolization for Ruptured MCA Aneurysm. A Case Report

SUMMARY

Complications during coil embolization of cerebral aneurysms include thromboembolic events, hemorrhagic complications related to procedural aneurysmal rupture and parent vessel perforation, and coil-related complications. The present report describes a rare coil-related complication involving spontaneous coil knotting.

Safety and immunogenicity of a vaccine targeting human papillomavirus types 6, 11, 16 and 18: a randomized, placebo-controlled trial in 176 Korean subjects

Human papillomavirus (HPV) is a major causative agent of anogenital warts and a necessary cause of cervical cancer. This report will serve to assess the safety and immunogenicity of quadrivalent (types 6, 11, 16, and 18) HPV L1 virus-like particle (VLP) vaccine in the Korean population. We performed a randomized, double-blind, placebo-controlled study in 176 volunteers aged 9-23 years. Using a 2:1 ratio for randomization, 117 women were assigned to quadrivalent HPV (20 mug type 6, 40 mug type 11, 40 mug type 16, and 20 mug type 18) vaccine and 59 women to placebo. Individuals received vaccine at day 1, month 2, and month 6 and provided blood samples for analysis at enrollment at month 7. Analyses were done as specified in the study protocol. Quadrivalent HPV vaccine was generally well tolerated, with no vaccine-related serious adverse experiences. Quadrivalent HPV vaccine induced seroconversion for each vaccine-related HPV type. At month 7, vaccine-induced type-specific antibody titer was high. In conclusion, administration of quadrivalent HPV VLP vaccine to Korean women aged 9-23 years was generally well tolerated and highly immunogenic.

Dihydroartemisinin enhances radiosensitivity of human glioma cells in vitro

PURPOSE

The antimalarial agent, artemisinin, also confers cancer-specific cytotoxic effects by reacting with ferrous iron atoms to form free radicals. Here, we investigated the radiosensitizing effects of dihydroartemisinin on glioma cells and assessed some possible mechanisms for these effects.

MATERIALS AND METHODS

U373MG glioma cells treated with various concentrations of dihydroartemisinin plus radiation, and efficiency of radiosensitization was assessed by clonogenic survival assay. Expression and activity of antioxidant enzymes, glutathione-S-transferase (GST) were quantified by western blot and enzymatic activity analyses, respectively.

RESULTS

Dihydroartemisinin showed higher cytotoxicity in the glioma cell lines than in the liver, breast or cervical cancer cell lines. In clonogenic survival assays, treatment with dihydroartemisinin alone dose-dependently reduced the number of U373MG colonies, while treatment with dihydroartemisinin plus gamma-irradiation showed far lower clonal survival than cultures treated with radiation or dihydroartemisinin alone. The radiosensitizing effect of dihydroartemisinin was blocked significantly by the free radical scavengers, NAC and TIRON, indicating association with dihydroartemisinin-induced ROS generation. In addition, the radiation-induced expression of endogenous GST was suppressed by treatment with dihydroartemisinin. The radiosensitizing effect of dihydroartemisinin was also markedly enhanced by the addition of holotransferrin

CONCLUSION

Taken together, our results strongly suggest that dihydroartemisinin triggers production of ROS and inhibits GST activity, leading to effective and therapeutically relevant radiosensitization of human glioma cells.

Glovax's perspective: opportunities and approaches to vaccine business in Asia

Glovax Co., Ltd. has focused on regional population needs, and assessed potentially interesting vaccine candidates for their safety, efficacy and cost-effectiveness. Economic analysis was made to identify the area of high commercial potential based on quantity demands and pricing flexibility. Epidemiological data on the target diseases were reviewed so that we could identify the vaccines of more limited interests worldwide but still of high significance in regional public health. Several viral vaccine products were selected as our priority including Japanese encephalitis and Hepatitis A vaccines. Extensive safety and clinical studies have been projected. To ensure that a safe and effective vaccine be supplied at the same quality level, new manufacturing facilities are being constructed in our region. Several approaches have been made to overcome technical, financial, and managerial obstacles. Close partnerships with industry, biomedical community and regulatory agencies may enhance the viability of our approach to be a successful vaccine player in this region.

Chronic hepatitis: in vivo proton MR spectroscopic evaluation of the liver and correlation with histopathologic findings

PURPOSE

To correlate the in vivo hydrogen 1 ((1)H) magnetic resonance (MR) spectroscopic features of the chronic hepatitis-involved liver with the histopathologic stages of fibrosis.

MATERIALS AND METHODS

Seventy-five patients with chronic hepatitis were examined with (1)H MR spectroscopy, which was performed in the right hepatic lobe. The peak areas of glutamine and glutamate complex (Glx), phosphomonoesters (PME), glycogen and glucose complex (Glyu), and lipid were measured on the liver spectra. The histopathologic features were correlated with the in vivo (1)H MR spectroscopic findings at each stage of chronic hepatitis. Fifteen healthy volunteers also were included as a control group.

RESULTS

(1)H MR spectroscopy depicted Glx, PME, Glyu, and lipid in all livers. In the normal livers, the calculated mean (+/- SD) relative metabolite-to-lipid ratios of Glx, PME, and Glyu were 0.14 +/- 0.04, 0.03 +/- 0.01, and 0.21 +/- 0.04, respectively. The mean value of each metabolite-to-lipid ratio was significantly different between all stages of chronic hepatitis, and with the exception of the mean ratio at the interval between stages 0 and 1 (P > .05), the mean value increased significantly with increasing stage (P < .05). A pronounced peak was demonstrated at 3.9-4.1 ppm at (1)H MR spectroscopy of all stages of chronic hepatitis except stage 0.

CONCLUSION

The increased Glx, PME, and Glyu levels relative to the lipid content with chronic hepatitis indicated the severity of fibrosis and thus were concordant with the histopathologic stages. In vivo (1)H MR spectroscopy might be a substitute for liver biopsy in the diagnosis and staging of chronic hepatitis.

Characterization of inwardly rectifying K(+) conductance across the basolateral membrane of rat tracheal epithelia

The rat primary cultured-airway monolayer has been an excellent model for deciphering the ion channel after nystatin permeabilization of its basolateral or apical membrane. Inwardly rectifying K(+) currents were characterized across the basolateral membrane in symmetrical HCO(-)(3)-free high K(+) Ringer's solution (125 mM) in this study. The potency of K(+) channel inhibitors against K(+) conductance was Ba(2+) (IC(50) = 5 microM) > Cs(+) (IC(50) = 2 mM) >> glybenclamide (IC(50) > 5 mM) >> TEA (IC(50) >> 100 mM). The application of basolateral Cs(+) changed K(+) conductance into an oscillating current, and its frequency (holding voltage = -100 mV) increased with increase in concentration of basolateral Cs(+) (0.05-5 mM) and in degree of hyperpolarization. Addition of basolateral Cs(+) blocked inward current strongly at -100 mV and hardly at all at -60 mV, giving a sharp curvature to the I-V relation of the IRK current. RT-PCR, Western blotting, and immunohistochemical analyses showed that Kir2.1 might be present in basolateral membrane of tracheal epithelia and plasma membrane of pulmonary alveolar cells.

Hepatocellular carcinoma with lung metastasis in a 9-year-old-boy

Hepatocellular carcinoma (HCC) remains chemoresistant and, therefore, the principal treatment of HCC is surgical resection. After a 9-year-old boy with huge HCC with lung metastasis received the 5 cycles of chemotherapy (cisplatin and Adriamycin), the lung metastasis had been resolved completely and the size of HCC in liver had decreased. Right hepatic trisegmentectomy was performed, and then the additional 3 cycles of chemotherapy was given. Currently, the patient shows no recurrence of HCC 42 months after surgical extirpation.

Efficacy of single-dose SA 14-14-2 vaccine against Japanese encephalitis: a case control study

BACKGROUND

In China, since 1989, an estimated 120 million children have been immunised with the SA 14-14-2 live-attenuated Japanese encephalitis (JE) vaccine at ages 1, 2, and 6 years. A case-control study of licensed vaccine found two doses to be 98% effective. Subsequently, researchers found that single-dose vaccine efficacy was high; we aimed to confirm this result.

METHODS

During July 11-24, 1999, 160000 doses of JE vaccine were given to children aged 1-15 years, resident in three districts of Nepal. Several cases of JE were admitted to hospital from early August. We obtained names and addresses of cases with serological evidence of a recent infection from Bheri Zonal Hospital, Nepalgunj. We did a matched case-control study and calculated the odds ratio of vaccination among JE cases and age-sex matched village controls.

FINDINGS

20 children, aged 1-15 years, were identified whose illness conformed with the JE case definition and were resident in villages receiving the vaccine. None of 20 JE cases had received JE vaccine compared with 326 of 557 age-sex matched village controls. The efficacy of a single dose of JE vaccine was 99.3% (CI 94.9-100%).

INTERPRETATION

A single dose of JE vaccine is highly efficacious in preventing Japanese encephalitis when administered only days or weeks before exposure to infection.

Radical excision of pediatric craniopharyngioma: recurrence pattern and prognostic factors

The purpose of our study was to investigate the pattern of recurrence and the prognostic factors for recurrence of pediatric craniopharyngiomas after radical excision. A series of 36 patients with craniopharyngiomas (21 boys and 15 girls; age range 1-15 years; mean 7.3 years) were reviewed. All patients had undergone radical excision without radiotherapy. The mean follow-up period was 52 months (range 1-149 months). Tumors recurred in 14 patients within 83 months (mean 31.4 months). The overall 5-year recurrence-free survival rate was 55%. Regular neuroimaging follow-up detected tumor recurrence while the lesions were still small before symptoms developed (P<0.05). At the first surgical procedure, the optic nerve/chiasm (n=23) was the most common adhesion site. The most frequent sites of recurrence were the optic nerve/chiasm (n=6) and the pituitary fossa (n=6). Tumor location was the single significant clinical predictor of recurrence. The 5-year recurrence-free survival rate was 39% for those who had an intrasellar tumor component and 81% for those who did not (P<0.05). The Ki-67 labeling indices (LIs) of primary tumors did not have prognostic value for recurrence. Recurrent tumors tended to have higher Ki-67 LIs than their primary counterparts. On the basis of this study, we concluded that craniopharyngiomas with intrasellar components should be followed cautiously and the necessity for regular follow-up should be emphasized, even when the tumor is "totally" resected.

Three-dimensional object recognition by use of a photorefractive volume holographic processor

We present a photorefractive volume holographic processor for recognition of three-dimensional (3D) objects. The templates are recorded by use of a volume hologram in a photorefractive LiNbO(3):Fe crystal located at the Fresnel diffraction region and correlated in real time with a 3D object illuminated by coherent light. Experimental results for recognition of 3D objects are presented and discussed. To the best of our knowledge, this is the first time a photorefractive volume holographic technique for 3D object recognition has been reported.

Studies on the interfacial characterization of O/W emulsion for the optimization of its treatment

Wastewater produced in the form of an o/w emulsion is difficult to treat properly because of its complex behavior. To acquire information for the optimization of emulsion controlling processes, the interfacial features of emulsion systems have been investigated in this work. The surface tension is found to decrease as the oil content is increased, and contact angle is influenced by the hydrophobicity of the substrate. The work of adhesion for substrates with different degrees of hydrophobicity has been estimated from the contact angle and surface tension. Temperature and pH have a significant influence on the turbidity and surface tension, and it is observed that electrophoretic characteristics of oil droplets are closely related with turbidity. Also, effects of inorganic salts and surfactants on the electrokinetic properties of emulsions have been considered, and the influence of coagulant on the stability is discussed through the calculation of potential energy of interaction between oil droplets. Adsorption and electrocoagulation processes have been attempted under various conditions in order to examine the practical treatment efficiencies of emulsion in relation to its interfacial characteristics.

Involvement of oxidative stress in ascorbate-induced proapoptotic death of PC12 cells

Ascorbate is a reducing agent, but it is also known to oxidize cellular components under specific conditions. The mechanism of this oxidative action, however, is not well established. Ascorbate treatment increased lipid peroxide content in PC12 cells, but did not increase quantities of lipid peroxide when homogenates of PC12 cells were treated with ascorbate, suggesting that cellular integrity is required for ascorbate to generate lipid peroxidation. However, dehydroascorbate increased lipid peroxide production in both intact PC12 cells and the cell homogenates. These differential effects of ascorbate and dehydroascorbate on intact cells versus homogenates suggest that the dehydroascorbate in cytosol induces an oxidative stress. Ascorbate in culture medium is rapidly oxidized to dehydroascorbate, which is transported into cells by a glucose transporter (GLUT). The GLUT antagonists wortmannin and cytochalasin B, or a high concentration of glucose, blocked (14)C uptake (from ascorbate) in a time-dependent manner and suppressed lipid peroxide production in PC12 cells. These observations support the concept that ascorbate is oxidized to dehydroascorbate, which is transported into cells via GLUT. The dehydroascorbate induces oxidative stress. The oxidative stress triggered apoptosis according to ceramide production, caspase-3 activation, and TUNEL. We have concluded that ascorbate is taken up after oxidation to dehydroascorbate via a "dehydroascorbate transporter" (GLUT), and the dehydroascorbate generates an oxidative stress which triggers apoptosis. These studies have significant implications for conditions under which a high concentration of ascorbate in a tissue is released during a period of hypoxia (e.g., stroke) and taken up during a reperfusion period as dehydroascorbate. Inhibiting uptake of dehydroascorbate may offer novel therapeutic strategies to alleviate brain damage during a reperfusion period.

Restriction fragment length dimorphism-PCR method for the detection of extended-spectrum beta-lactamases unrelated to TEM- and SHV-types

The diagnostic ability of the restriction fragment length dimorphism-polymerase chain reaction (RFLD-PCR) method was evaluated. Seven primer pairs, newly designed from 44 beta-lactamase genes encoding extended-spectrum beta-lactamases not related to TEM- and SHV-types, were used to differentiate OXA-2, FOX-3, CMY-3, IMP-1, and IMI-1 beta-lactamases. The RFLD-PCR was carried out successfully, and these genes were differentiated by the sizes of their PCR products and by the difference in restriction fragment length when each amplicon was digested with a unique restriction enzyme. This discriminatory detection of the genes was confirmed by sequencing the PCR products.

A case of hemorrhagic gallbladder paraganglioma causing acute cholecystitis

Gallbladder paraganglioma is a very rare tumor and so far only a few cases have been reported. Most of these were asymptomatic and were found incidentally during operation. Recently, we experienced a gallbladder paraganglioma that gave rise to hemorrhage, which in turn caused acute cholecystitis. Our case involved a 45 year-old female patient complaining of an intermittent right upper abdominal pain. After a preoperative evaluation, cholecystectomy and lymphadenectomy were performed under the impression of gallbladder cancer with acute cholecystitis. Postoperative pathologic examination revealed a hemorrhagic gallbladder paraganglioma accompanied by acute cholecystitis. Immunohistochemical staining of the chief cells for neuron specific enolase, chromogranin and synaptophysin were positive. Sustentacular cells also stained positively for S100 protein.