bluuebunny/crossref_metadata_2025 huggingface dataset:
Optknock: A bilevel programming framework for identifying gene knockout strategies for microbial strain optimization
Authors: Burgard Anthony P. , Pharkya Priti , Maranas Costas D.
Published: October 2003

The advent of genome‐scale models of metabolism has laid the foundation for the development of computational procedures for suggesting genetic manipulations that lead to overproduction. In this work, the computational OptKnock framework is introduced for suggesting gene deletion strategies leading to the overproduction of chemicals or biochemicals in E. coli. This is accomplished by ensuring that a drain towards growth resources (i.e., carbon, redox potential, and energy) must be accompanied, due to stoichiometry, by the production of a desired product. Computational results for gene deletions for succinate, lactate, and 1,3‐propanediol (PDO) production are in good agreement with mutant strains published in the literature. While some of the suggested deletion strategies are straightforward and involve eliminating competing reaction pathways, many others suggest complex and nonintuitive mechanisms of compensating for the removed functionalities. Finally, the OptKnock procedure, by coupling biomass formation with chemical production, hints at a growth selection/adaptation system for indirectly evolving overproducing mutants. © 2003 Wiley Periodicals. Biotechnol Bioeng 84: 647–657, 2003.
Expression of vitreoscilla hemoglobin improves growth and levels of extracellular enzyme in yarrowia lipolytica
Authors: Bhave Sanjay L. , Chattoo Bharat B.
Published: October 2003

Enhancement in oxygen uptake by high‐cell‐density cultivations has been achieved previously by expression of the bacterial hemoglobin gene from Vitreoscilla. The Vitreoscilla hemoglobin (VHb) gene was expressed in the yeast Yarrowia lipolytica to study the effect of expression in this commercially important yeast. The expression of VHb in this yeast was found to enhance growth, contrary to reported observations in wild‐type Saccharomyces cerevisiae in which there was no significant growth enhancement. VHb‐expressing Y. lipolytica exhibited higher specific growth rate, enhanced oxygen uptake rate, and higher respiratory activity. We report the beneficial effects of VHb expression on growth under microaerobic as well as under nonlimiting dissolved oxygen conditions. Earlier studies in Y. lipolytica have demonstrated inhibition of mycelia formation by respiratory inhibitors and poor nitrogen source, conditions poor for growth. VHb+ Y. lipolytica cells were more efficient at forming mycelia, indicating better utilization of available oxygen as compared with the VHb− cells. Expression of VHb was also found to increase the levels of enzyme ribonuclease secreted into the medium, a property that may be beneficial for producing heterologous proteins in Y. lipolytica. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 658–666, 2003.
Link between primary and secondary metabolism in the biotransformation of trimethylammonium compounds by escherichia coli
Authors: Cánovas M. , Bernal V. , Torroglosa T. , Ramirez J. L. , Iborra J. L.
Published: October 2003

The aim of this work was to understand the steps controlling the process of biotransformation of trimethylamonium compounds into L(−)‐carnitine by Escherichia coli and the link between the central carbon or primary and the secondary metabolism expressed. Thus, the enzyme activities involved in the biotransformation process of crotonobetaine into L(−)‐carnitine (crotonobetaine hydration reaction and crotonobetaine reduction reaction), in the synthesis of acetyl‐CoA (pyruvate dehydrogenase, acetyl‐CoA synthetase, and ATP:acetate phosphotransferase) and in the distribution of metabolites for the tricarboxylic acid (isocitrate dehydrogenase) and glyoxylate (isocitrate lyase) cycles, were followed in batch with both growing and resting cells and during continuous cell growth in stirred‐tank and high‐cell‐density membrane reactors. In addition, the levels of carnitine, crotonobetaine, γ‐butyrobetaine, ATP, NADH/NAD+, and acetyl‐CoA/CoA ratios were measured to determine how metabolic fluxes were distributed in the catabolic system. The results provide the first experimental evidence demonstrating the important role of the glyoxylate shunt during biotransformation of resting cells and the need for high levels of ATP to maintain metabolite transport and biotransformation (2.1 to 16.0 mmol L cellular/mmol ATP L reactor h). Moreover, the results obtained for the pool of acetyl‐CoA/CoA indicate that it also correlated with the biotransformation process. The main metabolic pathway operating during cell growth in the high cell‐density membrane reactor was that related to isocitrate dehydrogenase (during start‐up) and isocitrate lyase (during steady‐state operation), together with phosphotransacetylase and acetyl‐CoA synthetase. More importantly, the link between central carbon and L(−)‐carnitine metabolism at the level of the ATP pool was also confirmed. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 686‐699, 2003.
Data reconciliation and parameter estimation in flux‐balance analysis
Authors: Raghunathan Arvind U. , Pérez‐Correa J. Ricardo , Bieger Lorenz T.
Published: October 2003

Flux blance analysis (FBA) has been shown to be a very effective tool to interpret and predict the metabolism of various microorganisms when the set of available measurements is not sufficient to determine the fluxes within the cell. In this methodology, an underdetermined stoichiometric model is solved using a linear programming (LP) approach. The predictions of FBA models can be improved if noisy measurements are checked for consistency, and these in turn are used to estimate model parameters. In this work, a formal methodology for data reconciliation and parameter estimation with underdetermined stoichiometric models is developed and assessed. The procedure is formulated as a nonlinear optimization problem, where the LP is transformed into a set of nonlinear constraints. However, some of these constraints violate standard regularity conditions, making the direct numerical solution very difficult. Hence, a barrier formulation is used to represent these constraints, and an iterative procedure is defined that allows solving the problem to the desired degree of convergence. This methodology is assessed using a stoichiometric yeast model. The procedure is used for data reconciliation where more reliable estimations of noisy measurements are computed. On the other hand, assuming unknown biomass composition, the procedure is applied for simultaneous data reconciliation and biomass composition estimation. In both cases it is verified that the f measurements required to get unbiased and reliable estimations is reduced if the LP approach is included as additional conatraints in the optimization. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 700–709, 2003.
Application of multivirus spike approach for viral clearance evaluation
Authors: Valera Christine R. , Chen Janice W. , Xu Yuan
Published: October 2003

Viral contamination is a common risk to continuous cell line‐derived biologics. Viral validation is thus required for license applications. Viral validation for chromatography procedures is routinely performed by spiking a model virus into the load material and performing the chromatography procedures at small scale under conditions equivalent to the commercial scale. With traditional cell‐based infectivity assays, one can only spike one model virus at one time. Quantitative PCR methods (TaqMan) make it possible to spike multiple model viruses for a chromatography procedure simultaneously. TaqMan assays can quantify multiple types of viruses and other types of nucleic acid in a single sample without cross interference because of its extremely high specificity. Therefore, a multivirus spike approach was evaluated and compared to a single virus spike approach. The study was further extended to the evaluation of host cell DNA clearance. The data shows highly comparable viral and host cell DNA clearance between the single and multiple virus spike approaches. Application of a multivirus spike approach provides significant time, manpower, and cost savings for new drug development. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 714–722, 2003.
Value of endoscopic ultrasonography as a predictor of long-term survival in oesophageal carcinoma
Authors: Mariette C , Balon J M , Maunoury V , Taillier G , Van Seuningen I , Triboulet J P
Published: October 2003

Background

Endoscopic ultrasonography (EUS) is considered to be the best locoregional staging technique for cancer of the oesophagus. This study evaluated the relationship between preoperative EUS findings, completeness of surgical resection and survival.

Methods

Between January 1995 and July 2002, 150 patients who underwent EUS for staging of tumours of the oesophagus were analysed prospectively. All underwent surgical resection with curative intent without neoadjuvant treatment.

Results

Patient survival was significantly related to tumour (EUS T), node (EUS N) and Union Internacional Contra la Cancrum classification (EUS UICC) stage according to sonographic findings (P = 0·003, P = 0·009 and P = 0·004 respectively), and the presence of stenosis determined by EUS (P = 0·004). EUS T stage was a prognostic factor for survival (relative risk 1·7 (95 per cent confidence interval (c.i.) 1·1 to 3·0); P = 0·046). Complete surgical resection (R0) was also significantly related to EUS T, N and UICC classification (P < 0·001). EUS UICC stage was a factor predictive of R0 resection (relative risk 2·6 (95 per cent c.i. 1·4 to 4·8); P = 0·003).

Conclusion

R0 resection and survival of patients with tumours of the oesophagus were strongly related to endosonographic findings. These results support the proposal that EUS should be performed in all patients with oesophageal cancer, not only for staging patients before therapy but also to determine prognosis.
Comparison of stenting with emergency surgery as palliative treatment for obstructing primary left-sided colorectal cancer
Authors: Law W L , Choi H K , Chu K W
Published: October 2003

Background

Self-expanding metallic stents provide an alternative to surgery as definitive palliation in patients with obstructing colorectal cancer. This study aimed to compare the outcome of patients with obstruction due to primary left-sided colorectal cancer treated by palliative stenting with outcome in patients who had undergone surgery.

Methods

Patients with incurable obstructing primary colorectal cancer distal to the splenic flexure treated with emergency surgery (n = 31) or placement of a metallic stent (n = 30) from November 1997 to June 2002 were included. Data on the mortality, morbidity, necessity of intensive care and hospital stay for the two groups were compared. The subsequent outcomes, including the incidence of stoma creation and survival, were also analysed.

Results

The two groups were similar in terms of age, sex distribution and presence of co-morbidity. Insertion of metallic stents was successful in 29 of 30 patients. Hospital death occurred in four and eight patients in the study and control groups respectively (P = 0·335). Fewer patients with placement of a stent required intensive care (1 versus 11; P = 0·001) and the median hospital stay was shorter in patients with stenting (4 versus 8 days; P = 0·008). A stoma was subsequently created in four patients with stenting, whereas 15 patients who had emergency operation required a stoma (P = 0·005). The difference in median survival between the two groups was not statistically significant (107 versus 119 days; P = 0·088).

Conclusion

Self-expanding metallic stents are effective in the palliation of obstructing colorectal cancer. Placement of stents is associated with a shorter hospital stay, less likelihood of intensive care and a lower incidence of stoma creation, when compared with emergency surgery. Thus insertion of a metallic stent should be considered in patients with incurable obstructing colorectal cancer.
Role of postoperative computed tomography in patients with severe liver injury
Authors: Demetriades D , Karaiskakis M , Alo K , Velmahos G , Murray J , Asensio J
Published: October 2003

Background

The role of postoperative computed tomography (CT) in asymptomatic patients with severe liver injury has not been investigated. The aim of the present study was to investigate the nature and incidence of significant liver-related abnormalities detected by postoperative CT in asymptomatic patients with severe liver injury.

Methods

This was a prospective study of survivors with severe liver injury (grades III–V) who were treated surgically. The patients underwent CT to evaluate the liver after operation, irrespective of symptoms.

Results

During the study interval there were 181 patients with severe liver injury, of whom 49 fulfilled the criteria for inclusion. The overall incidence of liver-related complications detected by CT was 49 per cent (necrotic areas in the liver in seven patients, seven bilomas, four abscesses, three perihepatic collections and three false aneurysms). In the subgroup of 17 asymptomatic patients CT revealed four abnormalities: two large bilomas, one false aneurysm and one fluid collection. Two of these patients required therapeutic intervention and the other two remained under observation.

Conclusion

In view of the incidence of asymptomatic significant liver abnormalities following operative management of severe liver injury, it is recommended that these patients undergo routine postoperative CT.
Randomized clinical trial of laparoscopic cholecystectomy performed with mini-instruments
Authors: Sarli L , Iusco D , Gobbi S , Porrini C , Ferro M , Roncoroni L
Published: October 2003

Background

The outcomes after traditional laparoscopic cholecystectomy (LC; one 10-mm port, one 12-mm port and two 5-mm ports) and minilaparoscopic cholecystectomy (MLC; three 3-mm ports and one 12-mm port) for gallstone disease were compared.

Methods

The study was a randomized, single-blind trial comparing LC with MLC. Only elective patients were eligible for inclusion. LC was a routine procedure at the institution in which the study was performed, whereas MLC was introduced after a short training period. The randomization period was from January to December 2001.

Results

Of 175 patients who had elective minimal access cholecystectomy during the randomization period, 135 entered the trial: 68 underwent LC and 67 underwent MLC. The groups were matched for age, sex and preoperative characteristics. Median (range) operating times for LC and MLC were similar (45 (20–120) and 50 (20–170) min respectively). Intraoperative and postoperative complication rates, the time for the patient to resume walking, eating and passing stools, and median hospital stay were the same in the two groups. The level of postoperative pain was lower in the MLC group at 1 h (P = 0·011), 3 h (P = 0·012), 6 h (P = 0·003), 12 h (P = 0·052) and 24 h (P = 0·034). Patients who had MLC received fewer injections of analgesic (P = 0·036) and more patients in this group expressed satisfaction with the cosmetic result (P = 0·001).

Conclusion

MLC took a similar time to perform and caused less postoperative pain than the standard laparoscopic procedure. Reducing the port size further enhanced the advantages of laparoscopic over open cholecystectomy.
Duodenum- and spleen-preserving total pancreatectomy for end-stage chronic pancreatitis
Authors: Alexakis N , Ghaneh P , Connor S , Raraty M , Sutton R , Neoptolemos J P
Published: October 2003

Background

Total pancreatectomy may be warranted in patients with advanced chronic pancreatitis in whom partial resection has failed and in those with end-stage pancreatic function. A new operation, duodenum- and spleen-preserving total pancreatectomy, is described.

Methods

Nineteen consecutive patients with chronic pancreatitis who had duodenum- and spleen-preserving total pancreatectomy were studied.

Results

There were 15 men and four women with a median age of 40 (range 29–64) years. The aetiology was alcohol misuse in nine, hereditary pancreatitis in five and idiopathic in five patients. All patients had chronic intractable abdominal pain. Six had undergone pancreatic surgery previously and one had had multiple coeliac plexus blocks. There were ten postoperative complications in five patients, and one hospital death. The median hospital stay was 25 (range 10–84) days. There was a reduction in pain (P < 0·001) and analgesic use (P < 0·001) after surgery, and weight gain was noted at 12 and 24 months (P < 0·001). Nine patients required readmission to hospital, four because of surgical complications: adhesional obstruction in one, biliary stricture in two and duodenal obstruction in one. In the other five patients (four of whom had long-standing pre-existing diabetes mellitus) readmission was for better control of pain (three patients), diabetes mellitus (two), and diabetes-associated diarrhoea (two) or gastropathy (one).

Conclusion

Duodenum- and spleen-preserving total pancreatectomy has a role in selected patients with medically intractable pain from chronic pancreatitis.
Prediction of tumour involvement in remaining axillary lymph nodes when the sentinel node in a woman with breast cancer contains metastases
Authors: Nos C , Harding-MacKean C , Fréneaux P , Trie A , Falcou M C , Sastre-Garau X , Clough K B
Published: October 2003

Background

In a significant proportion of women with breast cancer, the sentinel node is the only involved node in the axilla. The purpose of this study was to identify factors associated with histologically positive non-sentinel lymph nodes.

Methods

Between 1997 and 2002, 800 women with early breast cancer underwent sentinel node biopsy. In 263 patients the node contained metastases, including 83 with micrometastases detected by immunohistochemistry (IHC), 40 micrometastases detected on haematoxylin, eosin and safranine (HES) staining, and 140 macrometastases. All clinical and histological criteria were recorded and analysed with reference to histology of the non-sentinel node.

Results

The risk of metastasis in the non-sentinel lymph node was related to the volume of the tumour in the sentinel node. Non-sentinel nodes were involved in five (6·0 per cent) of 83 women when the sentinel node contained only micrometastatic cells detected on IHC, and in three (7·5 per cent) of 40 women when micrometastases were detected by HES, compared with 55 (39·3 per cent) of 140 when the sentinel node contained macrometastases on HES staining. Univariate analysis revealed a significant association between non-sentinel node involvement and type of metastasis within the sentinel node, clinical primary tumour size, palpable axillary lymph nodes before operation, pathological primary tumour size and the presence of peritumoral lymphovascular invasion. On multivariate analysis, the type of metastasis within the sentinel node (P < 0·001), histological tumour size greater than 20 mm (P = 0·017) and the presence of palpable axillary nodes before operation (P = 0·014) remained significant.

Conclusion

Clinical and pathological factors associated with sentinel node histology can reliably predict women for whom further axillary clearance is recommended, but it is not yet possible to determine a subgroup of patients in whom the sentinel node is the only involved node and for whom further axillary treatment may be unnecessary.
Prognostic factors in resection of pulmonary metastasis from colorectal cancer
Authors: Watanabe I , Arai T , Ono M , Sugito M , Kawashima K , Ito M , Nagai K , Saito N
Published: October 2003

Background

The aim of this retrospective study was to evaluate characteristics of primary colorectal cancer and pulmonary metastases in order to identify prognostic factors for overall survival and risk factors for further intrapulmonary recurrence after resection of pulmonary metastases from colorectal cancer.

Methods

Forty-nine patients who underwent resection of pulmonary metastases from colorectal cancer were reviewed. The factors assessed were age, sex, pathological findings of the original colorectal cancer (depth, lymphatic invasion, venous invasion, lymph node metastasis, differentiation, Dukes' stage) and pulmonary metastasis (maximum tumour size, number of tumours, completeness of resection), serum carcinoembryonic antigen level, previous hepatectomy for liver metastases, and surgical procedure for resection of pulmonary metastasis. Overall survival and intrapulmonary recurrence were also reviewed.

Results

Survival rates after resection of pulmonary metastases were 78 per cent at 3 years and 56 per cent at 5 years. Solitary pulmonary metastases were significantly correlated with survival (P = 0·049). The pathological features of the primary colorectal cancer had no impact on survival. Histologically incomplete resection of pulmonary metastasis significantly correlated with pulmonary re-recurrence (P = 0·034).

Conclusion

Long-term survival can be expected after complete resection of pulmonary metastases arising from colorectal cancer, especially in patients with a solitary pulmonary metastasis.
Laparoscopic live donor nephrectomy
Authors: Brook N R , Nicholson M L
Published: October 2003

Removing disincentives to donation
Carcinoid tumour of the appendix
Authors: Goede A C , Caplin M E , Winslet M C
Published: October 2003

Background

Appendiceal carcinoid tumours are found in 0·3–0·9 per cent of patients undergoing appendicectomy. Controversy exists over the management following appendicectomy, especially with regard to the role of right hemicolectomy in patients with tumours smaller than 2 cm in diameter.

Methods and results

The literature pertaining to the behaviour of appendiceal carcinoids was reviewed in order to formulate indications for right hemicolectomy. Metastatic disease from appendiceal carcinoids is a rare occurrence, but is more common when lesions are larger than 2 cm in diameter. The risk–benefit balance of right hemicolectomy needs to be better defined, and an improved understanding of tumour cell biology may aid prognostic accuracy and decision-making.

Conclusion

There is limited evidence on which to base clear indications for right hemicolectomy in patients with a diagnosis of appendiceal carcinoid. Acceptable indications are carcinoids larger than 2 cm in size, any high-grade malignant carcinoid (including those with a high mitotic index), mesoappendiceal invasion, lesions at the base of the appendix with tumour-positive margins, and goblet cell adenocarcinoid tumours.
Patient to surgeon infections—fact or fiction
Authors: Nystrom P-O , Wittmann D
Published: October 2003

Occupational safety has its limits
Letter 1: Cold provocation testing and hand-arm vibration syndrome—an audit of the results of the Department of Trade and Industry for the evaluation of miners (Br J Surg 2003; 90: 1076–1079)
Authors: Lindsell C J
Published: October 2003

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses can be sent electronically via the BJS website (www.bjs.co.uk) or by post. All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Letters submitted by post should be typed on A4-sized paper in double spacing and should be accompanied by a disk.
Determination of the compositions of polysaccharides from Chinese herbs by capillary zone electrophoresis with amperometric detection
Authors: Wang Qingjiang , Ding Fei , Zhu Ningning , He Pingang , Fang Yuzhi
Published: October 2003

In this paper, capillary zone electrophoresis with amperometric detection (CZE‐AD) was applied to determine the compositions of hetero‐polysaccharides from Chinese herbs, Angelica sinensis and ﬂax by analyzing their hydrolyzed monosaccharides: fucose, galactose, glucose, arabinose, rhamnose and xylose. Under the selected optimum conditions, the six monosaccharides could be perfectly separated within 25 min and showed signiﬁcant current responses at copper electrodes. The linear ranges of the six monosaccharides were all from 5.0 × 10−6 to 2.0 × 10−4 mol L−1 and their detection limits were lower or near 1.0 × 10−6 mol L−1 (S/N = 3). Experiments showed that the Angelica sinensis polysaccharide was composed of fucose, galactose, glucose, arabinose, rhamnose and xylose (mole ratio 1.0:13.6:15.0:8.7:21.3:3.7), and the ﬂax polysaccharide was composed of galactose, glucose and arabinose (mole ratio 1.0:4.98:1.1). The purity of these polysaccharides leached by the introduced leaching method was 98.3 and 97.6%, respectively. Analyzing polysaccharides by this method has some merits of speed, simple instrumentation and operation, high sensitivity and high reproducibility. Copyright © 2003 John Wiley & Sons, Ltd.
Enantioselective determination of arotinolol in human plasma by HPLC using teicoplanin chiral stationary phase
Authors: Aboul‐Enein Hassan Y. , Hefnawy Mohamed M.
Published: October 2003

A sensitive enantioselective high‐performance liquid chromatography (HPLC) method was developed and validated to determine S‐(+)‐ and R‐(−)‐arotinolol in human plasma. Baseline resolution was achieved by using teicoplanin macrocyclic antibiotic chiral stationary phase (CSP) known as Chirobiotic T with a polar organic mobile phase consisting of methanol:glacial acetic acid:triethylamine, 100:0.1:0.1, (v/v/v) at a ﬂow rate of 0.8 mL/min and UV detection set at 317 nm. Human plasma was spiked with stock solution of arotinolol enantiomers and labetalol as the internal standard. The assay involved the use of liquid–liquid extraction procedure with ethyl ether under alkaline condition for human plasma sample prior to HPLC analysis. Recoveries for S‐(+)‐ and R‐(−)‐arotinolol enantiomers were in the range 93–103% at 200–1400 ng/mL level. Intra‐day and inter‐day precision calculated as %RSD was in the ranges 1.3–3.4 and 1.9–4.5% for both enantiomers, respectively. Intra‐day and inter‐day accuracies calculated as percentage error were in the ranges 1.2–3.5 and 1.5–6.2% for both enantiomers, respectively. Linear calibration curves in the concentration range 100–1500 ng/mL for each enantiomer showed a correlation coefﬁcient (r) of 0.9998. The limit of quantitation (LOQ) and limit of detection (LOD) for each enantiomer in human plasma were 100 and 50 ng/mL (S/N = 3), respectively. Copyright © 2003 John Wiley & Sons, Ltd.
Direct injection HPLC method for the determination of selected phenothiazines in plasma using a Hisep column
Authors: Pistos C. , Stewart James T.
Published: October 2003

A direct plasma injection HPLC method has been developed for the determination of selected phenothiazines (promethazine, promazine, chlorpromazine) using a Hisep column. The method is easy to perform and requires 20 µL of a ﬁltered plasma sample. The chromatographic run time is less than 11 min using a mobile phase of 15:85 v/v acetonitrile–0.18 m ammonium acetate pH 5.0 and UV detection at 254 nm. The method is linear in the concentration range 0.1–25 µg mL−1 (r > 0.99, n = 6) for each analyte with RSD less than 6%. Interday and intraday variability were found to be ≤14%. The limits of detection and quantitation were 0.1 (S/N > 3) and 0.25 µg mL−1 (S/N > 10), respectively, for each of the three phenothiazines. We can also apply this method to separate three other phenothiazines (ethopromazine, triﬂuoroperazine, prochlorperazine), although it lacks the selectivity to determine the concentration of all six drugs concurrently. The separation is feasible using these drugs in certain combinations. Copyright © 2003 John Wiley & Sons, Ltd.
Determination of methamphetamine and amphetamine in abusers' plasma and hair samples with HPLC‐FL
Authors: Nakashima Kenichiro , Kaddoumi Amal , Ishida Yukihiro , Itoh Takachika , Taki Kenji
Published: October 2003

This paper describes highly sensitive HPLC methods for the determination of amphetamine (AP) and methamphetamine (MP) in abusers' plasma and hair samples. AP and MP were derivatized with the ﬂuorescent reagent, DIB‐Cl, to yield a highly ﬂuorescent DIB‐derivatives of AP and MP, which were then analyzed by HPLC with ﬂuorescence detection at excitation and emission wavelengths of 325 and 430 nm, respectively. The separation was achieved on an ODS column with isocratic mobile phases composed of acetoniltrile and citrate buffer (55:45, v/v) for plasma samples and of acetonitrile–methanol–citrate buffer (45:20:37.5, v/v/v) for hair samples. The limits of detection were less than 0.87 ng/mL and 0.12 ng/mg in plasma and hair samples, respectively, for both AP and MP. The methods were then applied to the determination of MP and its metabolite AP in plasma obtained from two cases of illegally ingested MP and in one of the cases' hair received later. Case I was treated with dialysis; samples before and after dialysis were analyzed by the described method. After dialysis for 5 h, the total plasma levels of AP and MP decreased from 720 to 190 ng/mL. For case II, MP and AP levels were monitored for 3 days after digestion. Total plasma levels decreased from 57 ng/mL in the day of digestion to 11 ng/mL after 3 days. In hair samples, AP and MP could also be detected in very low concentrations. Copyright © 2003 John Wiley & Sons, Ltd.
Identiﬁcation and determination of ecdysone and phenylpropanoid glucoside and ﬂavonoids in Lamium maculatum by capillary zone electrophoresis
Authors: Shuya Cui , Xingguo Chen , Zhide Hu
Published: October 2003

The simultaneous determination of 20‐hydroxy ecdysone (1), 3,7‐dimethoxy‐quercetin (2), acteoside (3) and rutin (4) in the mixture of leaf and stem, and the ﬂower of Lamium maculatum has been investigated by capillary zone electrophoresis for the ﬁrst time. With an electrolyte containing 30 mmol/L borate, at pH 9.47 and 20 kV applied voltage, the four active compounds were completely separated within 5 min with satisfactory results. The effects of concentration of borate and electrolyte pH on electrophoretic behavior and separation were studied. Regression equations revealed linear relationships (correlation coefﬁcients 0.9998–0.9999) between the peak area of each analyte and the concentration. The levels of analytes in the different parts of Lamium maculatum were easily determined with recoveries ranging from 98.3 to 105.0%. Copyright © 2003 John Wiley & Sons, Ltd.
On the calculation of cross‐correlation spectral density functions within the model‐free approach
Authors: Canet Daniel , Bouguet‐Bonnet Sabine , Mutzenhardt Pierre
Published: October 2003

Comprehensive calculations are performed with the aim of arriving at a ready‐to‐use form for cross‐correlation spectral density functions. Axial symmetry is assumed for tensors associated with the two interactions involved in the cross‐correlation spectral density. Moreover, the derived formulas stem from the hypotheses of the “model‐free” approach, i.e., a (generally fast) local motion superposed to a (generally slow) molecular tumbling. The restriction of fast local motions imposes the definition of two different order parameters S and S′ associated with the principal direction of the two considered interactions and it is the product of these order parameters, which is present in the general expression of a spectral density function. The latter includes two terms. The first one corresponds to fast local motions and involves the factor 1/2(3 cos2α − 1), where α is the angle made by the symmetry axes of the two considered tensors. The second term concerns only molecular tumbling sensed by a (virtual) director. Finally, it is shown that, consistently with the model‐free approach, the product SS′ can be expressed as 1/2(3 cos2α − 1)S2 so that 1/2(3 cos2α − 1) factorizes the spectral density function. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part A 19A: 65–70, 2003.
Thermal relaxation and coherence dynamics of spin 3/2. II. Strong radio‐frequency field
Authors: van der Maarel Johan R.C.
Published: October 2003

The relaxation dynamics of the spin‐3/2 density operator under strong, on‐resonance radio‐frequency (RF) irradiation and in the presence of fluctuating and static quadrupolar interactions is reviewed. The evolution under the lock is analyzed for any value of the static quadrupolar interaction, ranging from isotropic systems to systems exhibiting large splitting far exceeding the line widths. For isotropic systems, relaxation under off‐resonance spin‐locking conditions and in the multiple‐pulse quadrupolar echo (QE) experiment is reviewed also. Spin‐lock pulse sequences optimized for the selective detection of nuclei involved in slow molecular motion and/or in anisotropic, liquid crystalline environment are discussed. In Part I, the classical relaxation dynamics of spin 3/2 was reviewed. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part A 19A: 117–133, 2003.
Nuclear magnetic resonance data processing. MestRe‐C: A software package for desktop computers
Authors: Cobas Juan Carlos , Sardina F. Javier
Published: October 2003

Magnetic Resonance Companion (MestRe‐C) is a software package that offers state‐of‐the‐art facilities for data processing, visualization, and analysis of high‐resolution nuclear magnetic resonance (NMR) data, combined with a robust, user‐friendly graphical interface that fully exploits the power and flexibility of the Windows platform. The program provides a variety of conversion facilities for most NMR spectrometer formats and includes all the conventional processing, displaying, and plotting capabilities of an NMR program, as well as more advanced processing techniques. A brief review of the basic concepts of NMR data processing is included also. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part A 19A: 80–96, 2003.
On the use of the stochastic Liouville equation in nuclear magnetic resonance: Application to R1ρ relaxation in the presence of exchange
Authors: Abergel Daniel , Palmer Arthur G.
Published: October 2003

The nuclear magnetic resonance (NMR) spin relaxation rate constant in the rotating frame of reference R1ρ provides information on microsecond to millisecond (μs‐ms) timescale kinetic processes that stochastically modulate the resonance frequencies of nuclear spins in molecules. Expressions for R1ρ are presented for two‐site chemical exchange using both the conventional perturbation approach for evolution of the density operator in the interaction frame of reference and the stochastic Liouville equation (SLE) for evolution of the average density operator in the rotating frame of reference. The former approach is limited to the fast‐exchange regime, in which the chemical exchange kinetics are faster than the frequency difference between spins in the two sites. The latter approach provides approximate expressions for R1ρ that are accurate when chemical exchange is not fast. Expressions for R1ρ that are accurate over the widest range of experimental conditions facilitate the interpretation of chemical exchange phenomena. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part A 19A: 134–148, 2003.
Pulsed field gradient nuclear magnetic resonance as a tool for studying drug delivery systems
Authors: Momot Konstantin I. , Kuchel Philip W.
Published: October 2003

Pulsed field gradient (PFG) nuclear magnetic resonance (NMR) is a versatile method for studying molecular transport and exchange in solution. Stejskal‐Tanner diffusion plots can be used to distinguish between chemical species even in the absence of chemical shift or T1 resolution, provided that certain conditions are satisfied. This can be used advantageously in colloidal drug delivery systems containing two drug populations, free and bound, which often differ only by their diffusion coefficients. We discuss the conditions required for the resolution of the two pools in Stejskal‐Tanner plots, as well as the effects of chemical exchange. We also present two practical examples of this analysis: surfactant micelles containing the general anesthetic propofol and lipid/water liquid crystalline mesophase vehicles (cubosomes). © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part A 19A: 51–64, 2003.
Quantification of magnetization transfer by sampling the transient signal using MT‐prepared single‐shot EPI
Authors: Helms Gunther , Hagberg Gisela E.
Published: October 2003

We describe the standard model for magnetization transfer (MT): a two‐pool system with pseudo‐linear exchange kinetics; under the influence of repetitive “MT‐pulses” that create arbitrary instantaneous saturation. The influence of the pulse repetition period on the steady state (Part I) and the transient behavior of the system (Part II) provides similar but not equivalent information about relaxation, exchange and saturation. A quantification of all six parameters was possible by sampling the transitions and steady state at pulse repetition times between 8 ms and 200 ms by means of single‐shot echo‐planar imaging of the human brain in vivo. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part A 19A: 149–152, 2003.
Atypical glandular cells—an update
Authors: Cangiarella Joan F. , Chhieng David C.
Published: October 2003

The diagnostic category of atypical glandular cells (AGC) in the Bethesda system for the reporting of cervicovaginal cytology has undergone significant modification since its inception in 1988. More than a decade later, this category remains a diagnostic challenge to both clinicians and cytopathologists because of the lack of uniform cytologic criteria, the lack of interobserver agreement in the diagnosis, and the lack of standardized patient management guidelines. This article reviews the current classification of AGC in the Bethesda system, the cytomorphologic features and differential diagnosis, the clinical significance of a diagnosis of AGC, and the clinical management of patients with AGC. This article provides a comprehensive clinicopathologic review of the category of AGC. Diagn. Cytopathol. 2003;29:271–279. © 2003 Wiley‐Liss, Inc.
Detection of herpes simplex virus DNA by in situ hybridization technique and polymerase chain reaction in Papanicolaou‐stained cervicovaginal smears
Authors: Iwa Nobuzo , Noguchi Hideki
Published: October 2003

Papanicolaou‐stained cervicovaginal smears from six patients with herpes simplex virus (HSV) infection were destained and reprocessed by means of in situ hybridization (ISH) technique to demonstrate the presence of HSV DNA utilizing biotinylated probe. Positive results were obtained in all six cases with intense staining signal for the HSV DNA in the nuclei of cells having a ground‐glass nuclear appearance as well as in multinucleated giant cells. Furthermore, a hybridization signal was also noted in smears that had been prepared as much as 3 yr previously. HSV type 2‐specific antigen was confirmed in six destained smears by means of immunoperoxidase staining. Moreover, polymerase chain reaction (PCR) was also performed for four patients from Pap‐destained cervicovaginal smears. Amplified HSV DNA was detected in all four cases as 106 basepair PCR products by polyacrylamide gel electrophoresis. The combined use of cytology and the ISH technique and PCR amplification was of great value for the rapid cytodiagnosis of genital infection of HSV. Diagn. Cytopathol. 2003;29:246–249. © 2003 Wiley‐Liss, Inc.
Histiocytic aggregates in benign nodular goiters mimicking cytologic features of papillary thyroid carcinoma (PTC)
Authors: Nassar Aziza , Gupta Prabodh , LiVolsi Virginia A. , Baloch Zubair
Published: October 2003

Macrophages/histiocytes are commonly seen in fine‐needle aspiration biopsy (FNAB) specimens of thyroid nodules with varying degrees of cystic change. In some cases the histiocytic component of a cystic thyroid nodule can occur as large tissue fragments with marked nuclear atypia, including elongated nuclei with chromatin clearing, nuclear grooves, and membrane thickening. These nuclear changes mimic cytologic features of papillary thyroid carcinoma (PTC), thus leading to diagnostic difficulty in interpretation of FNAB specimens of benign cystic thyroid nodules. We evaluated ethanol‐fixed Papanicolaou‐stained smears of 273 cases of FNAB thyroid specimens from goitrous nodules with cystic change. Twenty cases were selected due to the presence of large aggregates of histiocytic cells with the above‐mentioned nuclear atypia. An immunostain for histiocytic cells using CD68 was performed on alcohol‐fixed slides. Histiocytic cells in tissue fragments with nuclear atypia mimicking PTC nuclei showed strong cytoplasmic staining for CD68; thyroid follicular cells stained negative for CD68. We conclude that histiocytic cells in cystic goitrous nodules can show nuclear features, which appear similar to PTC nuclei. Immunostaining for CD68 may be of value in differentiating between benign cystic thyroid nodules with histiocytic aggregates that mimic cytologic features of papillary carcinoma, and PTC with cystic change. Diagn. Cytopathol. 2003;29:243–245. © 2003 Wiley‐Liss, Inc.
Metastatic ovarian Sertoli‐cell tumor: FNA findings with immunohistochemistry
Authors: Watson Brian , Siegel Cary L. , Ylagan Lourdes R.
Published: October 2003

A malignant Sertoli cell tumor of the ovary is a rare sex‐cord stromal derived neoplasm. Sertoli cell tumors account for ∼4% of Sertoli‐stromal cell tumors (Hsu et al., J Histochem Cytochem 1981;29:577–580). The diagnosis of this entity by fine‐needle aspiration and needle core biopsy can be difficult when the differential also includes a metastatic renal cell carcinoma, due to the overlap of both cytological and histological features. Here, we show that immunohistochemical staining on cytological material including alpha‐inhibin can be used to differentiate between these two malignant tumors. Diagn. Cytopathol. 2003;29:283–286. © 2003 Wiley‐Liss, Inc.
Fine‐needle aspiration smears from lipomatous hemangiopericytoma need not be confused with myxoid liposarcoma
Authors: Domanski Henryk A.
Published: October 2003

Lipomatous hemangiopericytoma (LHPC) is a rare benign soft tissue tumor that may mimic soft tissue sarcoma clinically. Despite the fact that LHPC shares most of the histologic features with solitary fibrous tumor, it may be occasionally misdiagnosed as myxoid liposarcoma or some other type of spindle‐cell sarcoma. While some studies have addressed the histological features and origin of LHPC, no reports of cytological findings have been published. The author describes the cytological features of LHPC in two patients with correlations to histological and clinical findings. One of aspirates was misdiagnosed as being myxoid liposarcoma, while the other one was correctly diagnosed by a combination of FNAB and core needle biopsy (CNB). Cytological evaluation of LHPC can be problematic due to its rarity and to its similarity with other spindle‐cell or fatty tumors. Correct diagnosis requires an awareness of cytologic features of this rare tumor and the use of ancillary studies. Diagn. Cytopathol. 2003;29:287–291. © 2003 Wiley‐Liss, Inc.
Effectiveness of the SurePath liquid‐based Pap test in automated screening and in detection of HSIL
Authors: Cengel Keith A. , Day Sarah J. , Davis‐Devine Sharon , Adams Christina L. , Madison‐Henness Darcy , Hartman Matthew E. , Freund Gregory G.
Published: October 2003

We have shown that SurePath when compared to conventional Paps fails to increase HSIL detection. In this study, assessment of test performance characteristics for the FocalPoint showed that sensitivity was 96% when manual screening was used as the “gold standard.” When cervical biopsy, however, was used as the “gold standard” FocalPoint sensitivity decreased to 93%, which was the same as manual screening. Examination of the FocalPoint “no further review” cases showed that 4/296 were SIL. To understand better the implication of an SIL diagnosis, cervical biopsies generated from SurePath and conventional Paps were compared. Conventional Paps diagnosed as LSIL had a biopsy LSIL:HSIL ratio of 3.1/1, while SurePath Paps had a biopsy LSIL:HSIL ratio of 1.5/1. These results indicate that when cervical biopsy is used as the “gold standard,” FocalPoint and manual screening of SurePath Paps have similar test performance but that the FocalPoint can fail to detect LSIL. Importantly, LSIL in a SurePath Pap is 1.6 times more likely to be HSIL on biopsy than LSIL in a conventional Pap. Diagn. Cytopathol. 2003;29:250–255. © 2003 Wiley‐Liss, Inc.
Rhabdoid meningioma: Intraoperative diagnosis using smear preparation
Authors: Kirby Patricia A.
Published: October 2003

Tumors with rhabdoid morphology were first described by Beckwith and Palmer in 1978 as aggressive renal tumors in very young children. Subsequently, rhabdoid tumors and tumors with rhabdoid features have been described in many other organ systems and all tend to have a poor outcome no matter what the histogenesis of the original tumor. Rhabdoid cells are plump, with abundant eosinophilic fibrillary to hyaline cytoplasm and peripheral, vesicular, variably pleomorphic nuclei. Nucleoli are invariably present. While their morphology is well recognized in processed biopsy material, their presence on a smear preparation can be quite startling. A case is presented to highlight the appearance of rhabdoid cells on an intraoperative smear preparation of a rhabdoid meningioma. An accompanying secretory component added to the complex picture. Diagn. Cytopathol. 2003;29:292–296. © 2003 Wiley‐Liss, Inc.
Correlation of manual screening and automated (AutoPap 300) analysis of conventional cervicovaginal smears with HPV typing using Digene HC II assay
Authors: Walts Ann E. , Thomas Premi
Published: October 2003

Efforts to improve the accuracy and efficacy of diagnosis of cervical cancer and its precursor lesions have prompted the development of new technologies, including several automated screening systems and human papillomavirus (HPV) hybrid capture assay. In this study of 89 conventional cervicovaginal (Papanicolaou [Pap]) smears, diagnoses based on manual screening are correlated with analyses by the AutoPap 300 primary screening system and results of the Digene HPV hybrid capture II assay. We found that (1) the AutoPap system did not “miss” (place in the “no further review” category) any of the high‐risk HPV DNA positive cases, (2) quintile assignments by the AutoPap system did not reliably predict the presence or absence of high‐risk HPV DNA, (3) cases of low‐grade squamous intraepithelial lesion (LGSIL) were associated with high‐risk rather than low‐risk HPV genotypes, (4) diagnoses of atypical squamous cells of undetermined significance (ASCUS) and above were more frequent in smears from patients whose cervicovaginal specimens tested positive rather than negative for high‐risk HPV DNA (37 of 45 vs 14 of 44) by the Digene HPV hybrid capture II assay, and (5) there was a high incidence of high‐risk HPV DNA among women whose smears did not show cytomorphologic changes of high‐grade squamous intraepithelial lesion (HGSIL). These findings emphasize that high‐risk HPV DNA is an indication of risk for HGSIL, not the equivalent for it. Diagn. Cytopathol. 2003;29:256–261. © 2003 Wiley‐Liss, Inc.