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PubMed1988

The impact of aggressive debulking surgery and cisplatin-based chemotherapy on progression-free survival in stage III and IV ovarian carcinoma.

Forty consecutive patients with stage III and IV invasive ovarian carcinoma were treated on a phase II protocol consisting of optimal debulking surgery, induction cisplatin, cisplatin, doxorubicin, and cyclophosphamide (PAC) chemotherapy, 6-month interval laparoscopy, reinduction cisplatin, PAC chemotherapy, and second-look procedure. All 40 patients have either disease progression or have completed the 12-month protocol. Eighty-seven percent of the patients (35) underwent optimal (less than or equal to 2 cm residual) debulking surgery before chemotherapy, in spite of the fact that 50% (20) were referred to Roswell Park Memorial Institute (RPMI) as inoperable after initial surgery elsewhere. There were no postoperative deaths and chemotherapy was started in less than or equal to 14 days in 97% of the patients. Of the 40 patients, 30% (12) achieved a pathologic complete remission (11) or a clinical complete remission (one patient refused second-look surgery). The estimated 3-year survival rate was 62%, but the 3-year progression-free survival rate was only 29%. The median survival time was 48 months. The estimated 3-year progression-free survival rate was 31% for residual disease less than or equal to 2 cm. For the five patients with residual disease greater than 2 cm, four died within 3 years. The median survival time of patients with less than or equal to 2 cm residual disease was 48 months, as compared with 21 months for those with greater than 2 cm residual disease. Although the estimated 3-year survival rate of 62% is noteworthy, the 3-year progression-free survival rate of only 29% is probably indicative that in spite of extensive debulking surgery and cisplatin-based chemotherapy as used in this protocol, the long range proportion of patients "cured" will remain small.

Adenocarcinoma↗
PubMed2026

Optimization of a Semi-nested PCR Protocol for Amplifying the Entire Spike Protein Region to Identify SARS-CoV-2 Variants in Wastewater.

Wastewater-based monitoring of SARS-CoV-2 and other pathogens is a widely adopted tool for assessing epidemic dynamics. While quantitative assays are commonly used to estimate infection levels in catchment populations, phylogenetic information-such as identifying circulating variants-is also crucial for public health. However, applying the widely used ARTIC protocol for full-genome sequencing to wastewater samples has proven challenging, likely due to the limited specificity and sensitivity of multiplex RT-PCR in such complex matrices. In this study, we developed and optimized a semi-nested RT-PCR assay targeting the full S-protein coding region (~4000 bases) for phylogenetic characterization of SARS-CoV-2 in wastewater. By reducing multiplexing and using single-plex reactions for both RT and PCR steps, we successfully amplified ~2000&#xa0;bp fragments. Amplicons were sequenced using the Flongle Flow Cell platform. The optimized method-consisting of reverse transcription with specific primers followed by three parallel single-plex semi-nested PCRs-yielded over 1,000 SARS-CoV-2-like reads per primer set in 30 out of 39 wastewater samples in treatment plants in Japan, including those with <10 copies per analyte. Variant proportions were estimated using a newly developed approach based on single-nucleotide variant pattern matrix, revealing the presence of multiple co-circulating variants, including XBB lineages, JN.1, and notably BA.2.75, which was undetected in domestic clinical surveillance. These results highlight the effectiveness of our approach for detecting temporal shifts in SARS-CoV-2 variants, even at low RNA concentrations.

Polymerase Chain Reaction↗
PubMedDate not supplied

GOS.SP.ASS.'98: an assessment for speech disorders associated with cleft palate and/or velopharyngeal dysfunction (revised).

In 1994 the present authors proposed a speech assessment protocol for speech disorders associated with cleft palate and/or velopharyngeal dysfunction known as GOS.SP.ASS. (Great Ormond Street Speech Assessment). In a recent survey undertaken to review the different speech assessment protocols used in six cleft palate centres in the UK, GOS.SP.ASS. was selected from six protocols as the optimal procedure for clinical and research purposes. The process of identifying an optimal procedure involved analysis of completed forms for each assessment. Analysis of the completed GOS.SP.ASS. forms revealed significant ambiguities in the protocol which led to differences in form completion. This paper describes important revisions to the original GOS.SP.ASS. protocol in order to ensure comparable data from different clinicians. This detailed speech assessment is now complemented by the Cleft Audit Protocol for Speech (CAPS), a tool recommended for clinical audit. As a result of close collaboration in their preparation, the results are directly comparable. In addition, the speech elicitation sentences and the phonetic diagram have been modified.

Cleft Palate↗
PubMed2003

Analysis and optimization of structure-based virtual screening protocols. (3). New methods and old problems in scoring function design.

Scoring function research remains a primary focus of current structure-based virtual screening (SVS) technology development. Here, we present an alternative method for scoring function design that attempts to combine crystallographic structural information with data derived from directly within SVS calculations. The technique utilizes a genetic algorithm (GA) to optimize functions based on binding property data derived from multiple virtual screening calculations. These calculations are undertaken on protein data bank (PDB) complex active sites using ligands of known binding mode in conjunction with "noise" compounds. The advantages of such an approach are that the function does not rely on assay data and that it can potentially use the "noise" binding data to recognize the sub-optimal docking interactions inherent in SVS calculations. Initial efforts in technique exploration using DOCK are presented, with comparisons made to existing DOCK scoring functions. An analysis of the problems inherent to scoring function development is also made, including issues in dataset creation and limitations in descriptor utility when viewed from the perspective of docking mode resolution. The future directions such studies might take are also discussed in detail.

Algorithms↗
PubMed1993

Quantification of myocardial muscarinic receptors with PET in humans.

The potential for noninvasive quantification of myocardial muscarinic receptors using PET data, a mathematical model, multi-injection protocols and 11C-labeled methylquinuclidinyl benzilate (MQNB) as a radioligand was previously demonstrated in dogs. The present study examines the possibility of optimizing the experimental protocol to make this approach suitable for human studies. For six normal subjects, the protocol included three injections: a tracer injection, followed 30 min later by an injection of an excess of unlabeled MQNB (displacement) and then 30 min later by a simultaneous injection of unlabeled and labeled MQNB (coinjection). The model input function was estimated from the PET data corresponding to the left ventricular cavity. This protocol enables a separate evaluation of all parameters of a ligand-receptor model which includes three compartments and seven parameters. The complexity of this three-injection protocol, however, appears to be inconvenient for clinical use. A simplified two-injection protocol (tracer injection and coinjection) was evaluated in five other normal subjects and the results were compared to those obtained with the three-injection protocol. In regions of interest over the left ventricle, the mean value of the receptor concentration B'max and the equilibrium dissociation constant Kd were 26 +/- 7 pmole/ml tissue and 2.0 +/- 0.5 pmole/ml tissue, respectively. The possible existence of nonspecific binding was studied in two subjects using a double-displacement protocol. The corresponding rate constant was found to be very low (0.03 min-1).

Adult↗
PubMed2002

Spontaneous bacterial peritonitis in patients with hepatic cirrhosis: evaluation of a treatment protocol at specialized units.

INTRODUCTION: Spontaneous bacterial peritonitis is a common and severe complication in patients with cirrhosis and ascitis. Its prognosis clearly depends on its precocious clinical recognition and efficacious therapy. AIM: To optimize a treatment protocol, after auditing clinical efficacy and describe microorganisms implicated at our institution. MATERIAL AND METHODS: Retrospective study of clinical files of patients with hepatic cirrhosis with positive culture of ascitic fluid (AF) and/or an AF polymorphonuclear (PMN) count of more than 250/mm3, treated at our units between 1st January, 2000 and 31st December, 2001 (n = 38). Patients showed a median age of 49 years (30-76), 63% of which were male. Forty-eight percent were classified as belonging to Child-Pugh B class, and 52% to C. RESULTS: First, considering cases with PMN > 250/mm3 (n = 29), antibiotics were given to all patients (cefotaxime and ampiciline). Fifty-two percent had hepatic encephalopathy, 42% had fever, 66% abdominal pain. In 42% a microorganism was isolated. Although 24% of fatal cases (only two related to infection), we noted a 73% clinical and laboratorial response. Five patients (72%) that died, showed renal failure by the time of death. Second, in all cases with positive culture of ascitic fluid (n = 21), 42% of which with PMN > 250/mm3 and 9 monobacterial nonneutrocytic bacterascites' cases, one only agent was found: E. coli in 36%, Streptococci (37%), Staphylococci (14%), and other (14%): Klebsiella oxytoca, n = 1; Salmonella enteritidis, n = 1; Enterococcus faecium, n = 1, Acinectobacter anitratus, n = 1. Only one of the agents, E. faecium (3%) showed in vitro sensitivity exclusively to ampiciline; all other were cefotaxime sensitivite. CONCLUSIONS: Our protocol will be modified, to treat patients with spontaneous bacterial peritonitis with cefotaxime, as monotherapy. Albumin infusion will also be added to the protocol, as, we found renal failure to be an important negative prognosis factor.

Adult↗
PubMed1997

The determination of membrane permeability coefficients of canine pancreatic islet cells and their application to islet cryopreservation.

Sufficient numbers of pancreatic islets for successful allotransplantation can be achieved by storing and then pooling islets from several donors. Optimal MHC matching and infectious disease screening also require long-term storage of islets, and cryopreservation is currently the only practical approach. Cryopreservation protocols may be optimized by modeling the changes in cell volume and the associated damage incurred during cryoprotectant addition and dilution and during cooling and warming. The objective of the present work was to determine the following biophysical parameters of canine islet cells; the osmotically inactive cell volume (Vb), hydraulic conductivity (Lp), cryoprotectant permeability coefficient (Ps), and the reflection coefficient sigma. A determination of these parameters allows the simulation of cell responses using computer models. Islets were isolated by collagenase digestion and Euro-Ficoll purification. After 24 h culture, islets were dissociated into single cells using trypsin and 2 mM EGTA. The kinetic change in cell volume as a function of time after exposure to 2 M dimethyl sulfoxide (Me2SO) was measured using an electronic particle counter at 22, 5, and -3 degrees C. At -11 degrees C, cells were preloaded with 1 M Me2SO and exposed to 4 M Me2SO to prevent the formation of ice in the working solution. Kedem-Katchalsky theory was used to describe the cell volume change kinetics, and a three-parameter curve fitting was performed using the Marquardt-Levenberg method to determine Lp, Ps, and sigma values. The Lp was determined to be 0.19 +/- 0.05, 0.037 +/- 0.005, 0.020 +/- 0.003, and 0.013 +/- 0.005 micron.min-1.atm-1 (mean +/- SD) at 22, 5, -3, and -11 degrees C, respectively. The Ps values were 1.05 +/- 0.50, 0.15 +/- 0.04, 0.096 +/- 0.028, and 0.067 +/- 0.029 x 10(-3) cm.min-1 at 22, 5, -3, and -11 degrees C, respectively. The sigma values were 0.81 +/- 0.16, 0.91 +/- 0.09, 0.80 +/- 0.21, and 0.98 +/- 0.04 at 22, 5, -3, and -11 degrees C, respectively. The temperature dependence or activation energy of Lp and Ps was calculated, using the Arrhenius equation, to be 12.7 and 13.5 kcal.mol-1, respectively. These permeability parameters were used to calculate cell water loss and the likelihood of lethal intracellular freezing during cooling, as well as both water flux and solute concentration gradients across the cell membrane during warming.

Animals↗
PubMed2004

High-accuracy amplification of nanogram total RNA amounts for gene profiling.

Microarray-based gene profiling of laser-assisted microdissected tissues or clinical biopsies is still a challenge since the amount of total RNA in such samples is limited and amplification of RNA is mandatory. Representative amplification of mRNA is highly dependent on the reverse transcription reaction, which is error prone, and on the number of amplification cycles. To improve the accuracy of RNA amplification, we optimized, combined, and tested different amplification strategies for Affymetrix oligonucleotide array hybridization. We demonstrate that different protocols differ significantly in quality of mRNA amplification. To demonstrate the accuracy and reproducibility of our optimized protocol in a clinical setting, we analyzed total RNAs from laser-assisted, microdissected cells of human prostate tissues. On the basis of these results, we recommend a standard reverse transcription reaction for small-sample-transcriptome profiling experiments as part of the Minimal Information about a Microarray Experiment (MIAME) set of standards.

Animals↗
PubMed2003

Species specific identification of the Neofabraea pathogen complex associated with pome fruits using PCR and multiplex DNA amplification.

Five species of pathogenic fungi belong to Neofabraea. One of these, N. krawtzewii (syn. N. populi), is responsible for bark lesions on poplar (Populus) trees. The other four species cause post-harvest bull's eye rot of pome fruits, and at least two of these also cause bark cankers on pome fruit trees. Morphological variation among these species is slight, and overlap in geographic range sometimes occurs. As a consequence, identification based on conventional criteria can be tenuous. PCR primers with putative species specificity were developed following genetic analysis of the beta-tubulin gene for isolates of each of the five species of Neofabraea. PCR conditions required to achieve specificity of the primer sets were determined, and a multiplex PCR protocol was developed to optimize their diagnostic utility on apple fruits. A protocol with higher annealing temperatures in the initial PCR cycles followed by lower temperatures in later cycles gave complete species-specificity when the primer sets were used individually and in multiplex, resulting in successful detection of the pathogens from axenic culture and infected apple fruits.

Ascomycota↗
PubMed2001

Early high-frequency oscillatory ventilation versus synchronized intermittent mandatory ventilation in very low birth weight infants: a pilot study of two ventilation protocols.

OBJECTIVE: To evaluate the feasibility of conducting a prospective, randomized trial comparing early high-frequency oscillatory ventilation (HFOV) to synchronized intermittent mandatory ventilation (SIMV) in very low birth weight (VLBW) premature infants. This pilot study evaluated two ventilator management protocols to determine how well they could be implemented in a multicenter clinical trial. Although this pilot study was not powered to detect differences in outcome, we also collected outcome data. DESIGN: Prospective, multicenter, randomized pilot study. SETTING: Seven tertiary-level intensive care nurseries with previous experience with both HFOV and flow-triggered SIMV. PATIENTS: Fifty infants weighing 501 to 1200 g, less than 4 hours of age, who had received one dose of surfactant and required ventilation with mean airway pressure > or =6 cm H2O and F(I)O2 > or =0.25, and had an anticipated duration of ventilation greater than 24 hours. INTERVENTIONS: Patients were stratified by birth weight and prenatal steroid status, then randomized to either HFOV or SIMV with tidal volume monitoring. Ventilator management for patients in both study arms was strictly governed by protocols that included optimizing lung inflation and blood gases, weaning strategies, and extubation criteria. MEASUREMENTS: Data were collected using the tools planned for the larger collaborative study. Protocol compliance was closely monitored, with successive changes in the protocol made as necessary to improve clarity and increase compliance. The incidence of major neonatal adverse outcomes was recorded. MAIN RESULTS: Data are presented for 24 HFOV and 24 SIMV infants (two infants, twins, were withdrawn from the study at parent's request). Nineteen of the 24 HFOV infants and 20 of the 24 SIMV infants survived to 36 weeks corrected age. Age at final extubation for survivors was 16+/-16 (mean+/-SD) days for HFOV infants and 24+/-24 days for SIMV infants. At 36 weeks corrected age, 14 of the 19 HFOV survivors were extubated and in room air, whereas 5 required supplemental oxygen. In comparison, 6 of the 20 SIMV survivors were extubated and in room air, whereas 14 required supplemental oxygen. Grade III/IV IVH and/or periventricular leukomalacia occurred in 2 HFOV and 2 SIMV patients. Overall compliance with the ventilator protocols was 82% for the SIMV protocol, and 88% for the HFOV protocol. CONCLUSIONS: The preliminary outcome data supports conducting the large randomized trial, which began in July of 1998. The protocols for the ventilator management of VLBW infants, both with HFOV and with SIMV were easily implemented and consistently followed, and are presented here.

Age Factors↗
PubMed1997

Influence on asthma morbidity of asthma education programs based on self-management plans following treatment optimization.

The objective of this study was to evaluate the effectiveness of an asthma education program on morbidity, knowledge, and compliance with inhaled corticosteroid treatment using a prospective, randomized, controlled, one-year-before/one-year-after protocol. After rigorous optimization of asthma therapy under the care of respirologists, patients were assigned to one of three groups: Group C (control group: no formal education), Group P (education and action plan based on peak-flow monitoring), and Group S (education with action plan based on monitoring of asthma symptoms). A total of 188 subjects with moderate to severe asthma were enrolled and 149 completed the study. Asthma morbidity decreased significantly in all groups (p = 0.001). Mean values one-year-before/one-year-after in Groups C, P, and S were: unscheduled medical visits, 2.4/0.8, 2.3/0.7, and 1.9/ 0.7; hospitalizations, 0.21/0.04, 0.24/0.04, and 0.40/0.09; oral steroid treatments; 1.3/0.5, 1.2/0.7, and 1.3/0.9; absenteeism from work/school, 9.6/5.2, 8.8/2.2, and 6.3/2.9. Between-group differences did not reach statistical significance (p > 0.05). Asthma knowledge increased in both educated groups compared with the control group (p < 0.001) as did short-term compliance with inhaled corticosteroids. These results confirm that treatment optimization coupled with sustained high quality care in motivated patients can lead to a significant decrease in asthma morbidity. In such clinical settings, structured asthma education significantly improved short-term compliance with treatment and knowledge about asthma, although it could not add extra benefit with regard to morbidity. Nevertheless, this study does not refute the potential benefit of educational interventions aimed at improving asthma-related morbidity over a longer time period or in patients with less optimal care or with high-risk factors.

Absenteeism↗
PubMed2006

Optimized neuronal differentiation of murine embryonic stem cells: role of cell density.

Neuronally differentiated embryonic stem (ES) cells offer a flexible and extremely potent model to study nervous system development and disease. A variety of protocols have been described to facilitate neuronal differentiation. The density of ES cells used for neuronal differentiation has striking effects on the proportion and purity of the derived neuronal cells. Here, the protocols used to optimize ES cell density in neuronal differentiation with and without an initial aggregation step are described.

Animals↗
PubMed2004

Scanning protocol choice affects optical coherence tomography (OCT-3) measurements.

PURPOSE: To determine the optimal OCT-3 scanning protocol. METHODS: Normal subjects, ocular hypertensive, and open-angle glaucoma patients were enrolled. The "fast" RNFL scan protocol consists of 3 consecutive circular scans, each containing 256 A-scans obtained in a single 1.92 second session. The "regular" RNFL scan protocol contains 3 separate circular scans, each of which consists of 512 A-scans and is obtained in 1.28 seconds (total 3.84 seconds). A customized 256-point scan was created from the 512-point "regular" RNFL scan by extracting the RNFL measurements from every second point. Mean RNFL thickness measurements and mean coefficients of variation (CV) were calculated for each of the scan types. RESULTS: Thirty-one eyes with visual field defects (31 glaucoma eyes) and 30 eyes with normal fields (10 normal and 20 ocular hypertensive eyes) were enrolled. There was no difference in RNFL thickness or CV between fast, regular, or customized RNFL scans in the eyes with VF defects (P > 0.05 for all comparisons). Although eyes with normal fields showed no difference in CV between fast, regular, and customized RNFL scans (P > 0.05 for all comparisons), there was a thicker RNFL measurement using the fast RNFL scan (P = 0.01). CONCLUSIONS: Optimal sampling density for OCT-3 assessment of parapapillary RNFL thickness is not more than 256 axial determinations. Although both scanning protocols have good reproducibility, the scanning protocol should remain constant during serial OCT-3 evaluation.

Adult↗
PubMedDate not supplied

Evaluation of retrospective multisector and half scan ECG-gated multidetector cardiac CT protocols with moving phantoms.

PURPOSE: We evaluated independently retrospective half scan and multisector mode manufacturer's protocols and compared them with modified acquisition protocols to determine optimal imaging parameters for cardiac scanning. MATERIALS AND METHODS: Data were acquired using two fabricated gated moving phantoms. In half scan mode, the manufacturer's recommended pitch values were compared with adjacent values at different motion rates. In multisector mode, the manufacturer's protocols were compared with ones with different gantry speeds and pitch values at the same motion rates. Weighted CT dose indexes (CTDI) were obtained for all protocols. Gated and reformatted reconstructed images of the moving phantoms were evaluated. RESULTS: In half scan mode, slightly better image quality was observed by lowering the pitch value, but with an increase of 6.3% of the weighted CTDI. Better results were obtained in multisector mode by lowering the pitch value up to 0.2, but with an increase of 14.3% of the weighted CTDI. Optimal images were obtained with the lowest temporal resolution. CONCLUSIONS: Gated moving phantom studies offer the advantage of testing acquisition protocols of complex motions and of helping to establish appropriate protocols.

Electrocardiography↗
PubMed2006

Extraction of inhibitor-free metagenomic DNA from polluted sediments, compatible with molecular diversity analysis using adsorption and ion-exchange treatments.

PCR inhibitor-free metagenomic DNA of high quality and high yield was extracted from highly polluted sediments using a simple remediation strategy of adsorption and ion-exchange chromatography. Extraction procedure was optimized with series of steps, which involved gentle mechanical lysis, treatment with powdered activated charcoal (PAC) and ion-exchange chromatography with amberlite resin. Quality of the extracted DNA for molecular diversity analysis was tested by amplifying bacterial 16S rDNA (16S rRNA gene) with eubacterial specific universal primers (8f and 1492r), cloning of the amplified 16S rDNA and ARDRA (amplified rDNA restriction analysis) of the 16S rDNA clones. The presence of discrete differences in ARDRA banding profiles provided evidence for expediency of the DNA extraction protocol in molecular diversity studies. A comparison of the optimized protocol with commercial Ultraclean Soil DNA isolation kit suggested that method described in this report would be more efficient in removing metallic and organic inhibitors, from polluted sediment samples.

Adsorption↗
PubMed2002

Multiplex sequence variation detection throughout the CFTR gene appropriate for preimplantation genetic diagnosis in populations with heterogeneity of cystic fibrosis mutations.

Cystic fibrosis (CF) is one of the most important genetic diseases requiring prevention programmes. Preimplantation genetic diagnosis (PGD) represents an alternative to prenatal diagnosis, and is especially appropriate for couples with an unsuccessful reproductive history. For clinical application, protocols must be optimized to minimize PCR failure, allelic drop-out (ADO) and contamination, while simultaneously detecting a wide spectrum of CF genotypes. We have developed a flexible multiplex PCR protocol allowing analysis of sequence variations in any combination amongst seven CFTR gene exons (4, 10, 11, 13 in two parts, 14b, 17b and 21) by nested PCR and denaturing gradient gel electrophoresis analysis, along with analysis of a fluorescently labelled intragenic microsatellite (IVS8CA). The experiments were carried out on 390 single lymphocytes from three CF patients, one heterozygote and one non-CF individual. PCR efficiency of the exons ranged from 90 to 100%, and ADO from 0 to 3.8%. IVS8CA was co-amplified with a PCR efficiency of 92.4 and 10.8% ADO. The present method overcomes the need for separate assays for each CFTR gene mutation. Additionally, it facilitates analysis of any informative linked polymorphic sequence variation (within the seven exons) along with analysis of a microsatellite, which is useful (when informative) for minimizing misdiagnosis and/or indirect diagnosis. This method proved robust and flexible for diagnosing diverse CF genotype combinations in single cells.

Cystic Fibrosis↗
PubMed1987

Cancer therapy by biological response modifiers.

Biological response modifiers (BRMs) are agents or approaches that modify the relationship between the tumor and host by modifying the host's biological responses to tumor cells, with resultant therapeutic effects. BRMs include immunomodulators and components of the immune system, e.g. cytokines, antibodies and effector cells. A central challenge in the development of BRMs for therapy of cancer patients is to determine the main mechanism of action of each agent and by monitoring for effects of treatment on the key parameters, optimize the treatment protocol. The experience to date with interferons and with interleukin-2 (IL-2) is summarized, to illustrate both the promise of BRMs and the difficulties in determining the optimal therapeutic regimen and in turn this potential for more effective treatment of cancer. A new sequence of clinical trials for clinical evaluation of BRMs is described, with an emphasis on treatment of patients with minimal tumor burden.

Animals↗
PubMed1999

Matrix optimization for matrix-assisted laser desorption/ionization mass spectrometry of oligosaccharides from human milk.

Neutral and acidic oligosaccharides from human milk were analyzed by matrix-assisted laser desorption/ionization mass spectrometry (MALDI/MS). These experiments require suitable matrices; their selection and particularly their preparation protocols must be optimized. Important criteria are sensitivity, reproducibility, tolerance against impurities and resolution over a wide mass range. For analytical investigations of these oligosaccharides, containing labile fucosylated and sialylated components, another property of a matrix becomes a significant factor, namely the influence on ion stability and the extent of (metastable) fragmentation. The experience gained with the MALDI/MS of neutral and acidic oligosaccharides is summarized taking into account different intentions of measurement and typical problems, such as impurities after enzymatic treatment. For a rapid screening of an oligosaccharide sample, superior results were obtained with a new preparation technique using 5-chloro-2-mercaptobenzothiazole (CMBT) as the first layer for 2,5-dihydroxybenzoic acid. For structural analysis by post-source decay, CMBT as the first layer for 3-aminoquinoline is a favoured preparation protocol, because extensive fragmentation is achieved. For acidic oligosaccharides, a special preparation protocol makes it possible to determine the number of sialic acids by inducing highly effective cationization. Matrix-assisted laser desorption/ionization mass spectrometry; matrices; oligosaccharides; post-source decay.

Gentisates↗